Search results for: clustering comparison.

Authors: Miriam I. Lautenschläger, Max H. Scheiwe, Kay A. Weidenmann, Frank Henning, Peter Elsner

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Due to increasing environmental awareness jute fibers are more often used in fiber reinforced composites. In the Sheet Molding Compound (SMC) process, the mold cavity is filled via material flow allowing more complex component design. But, the difficulty of using jute fibers in this process is the decreased capacity of fiber movement in the mold. A comparative flow study with jute nonwoven reinforced SMC was conducted examining the influence of the fiber volume content, the grammage of the jute nonwoven textile and a mechanical modification of the nonwoven textile on the flowability. The nonwoven textile reinforcement was selected to support homogeneous fiber distribution. Trials were performed using two SMC paste formulations differing only in filler type. Platy-shaped kaolin with a mean particle size of 0.8 μm and ashlar calcium carbonate with a mean particle size of 2.7 μm were selected as fillers. Ensuring comparability of the two SMC paste formulations the filler content was determined to reach equal initial viscosity for both systems. The calcium carbonate filled paste was set as reference. The flow study was conducted using a jute nonwoven textile with 300 g/m² as reference. The manufactured SMC sheets were stacked and centrally placed in a square mold. The mold coverage was varied between 25 and 90% keeping the weight of the stack for comparison constant. Comparing the influence of the two fillers kaolin yielded better results regarding a homogeneous fiber distribution. A mold coverage of about 68% was already sufficient to homogeneously fill the mold cavity whereas for calcium carbonate filled system about 79% mold coverage was necessary. The flow study revealed a strong influence of the fiber volume content on the flowability. A fiber volume content of 12 vol.-% and 25 vol.-% were compared for both SMC formulations. The lower fiber volume content strongly supported fiber transport whereas 25 vol.-% showed insignificant influence. The results indicate a limiting fiber volume content for the flowability. The influence of the nonwoven textile grammage was determined using nonwoven jute material with 500 g/m² and a fiber volume content of 20 vol.-%. The 500 g/m² reinforcement material showed inferior results with regard to fiber movement. A mold coverage of about 90 % was required to prevent the destruction of the nonwoven structure. Below this mold coverage the 500 g/m² nonwoven material was ripped and torn apart. Low mold coverages led to damage of the textile reinforcement. Due to the ripped nonwoven structure the textile was modified with cuts in order to facilitate fiber movement in the mold. Parallel cuts of about 20 mm length and 20 mm distance to each other were applied to the textile and stacked with varying orientations prior to molding. Stacks with unidirectional orientated cuts over stacks with cuts in various directions e.g. (0°, 45°, 90°, -45°) were investigated. The mechanical modification supported tearing of the textile without achieving benefit for the flowability.

Keywords: filler, flowability, jute fiber, nonwoven, sheet molding compound

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Authors: Nicolas R. Finkler, Wesley A. Saltarelli, Taison A. Bortolin, Vania E. Schneider, Davi G. F. Cunha

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Estimating the relative contribution of nonpoint or point sources of pollution in low-orders streams is an important tool for the water resources management. The location of headwaters in areas with anthropogenic impacts from urbanization and agriculture is a common scenario in developing countries. This condition can lead to conflicts among different water users and compromise ecosystem services. Water pollution also contributes to exporting organic loads to downstream areas, including higher order rivers. The purpose of this research is to preliminarily assess nutrients and solids loads exported by water bodies located in watersheds with different types of land uses in São Carlos - SP (Latitude. -22.0087; Longitude. -47.8909) and Caxias do Sul - RS (Latitude. -29.1634, Longitude. -51.1796), Brazil, using regression analysis. The variables analyzed in this study were Total Kjeldahl Nitrogen (TKN), Nitrate (NO3-), Total Phosphorus (TP) and Total Suspended Solids (TSS). Data were obtained in October and December 2015 for São Carlos (SC) and in November 2012 and March 2013 for Caxias do Sul (CXS). Such periods had similar weather patterns regarding precipitation and temperature. Altogether, 11 sites were divided into two groups, some classified as more pristine (SC1, SC4, SC5, SC6 and CXS2), with predominance of native forest; and others considered as impacted (SC2, SC3, CXS1, CXS3, CXS4 and CXS5), presenting larger urban and/or agricultural areas. Previous linear regression was applied for data on flow and drainage area of each site (R² = 0.9741), suggesting that the loads to be assessed had a significant relationship with the drainage areas. Thereafter, regression analysis was conducted between the drainage areas and the total loads for the two land use groups. The R² values were 0.070, 0.830, 0.752 e 0.455 respectively for SST, TKN, NO3- and TP loads in the more preserved areas, suggesting that the loads generated by runoff are significant in these locations. However, the respective R² values for sites located in impacted areas were respectively 0.488, 0.054, 0.519 e 0.059 for SST, TKN, NO3- and P loads, indicating a less important relationship between total loads and runoff as compared to the previous scenario. This study suggests three possible conclusions that will be further explored in the full-text article, with more sampling sites and periods: a) In preserved areas, nonpoint sources of pollution are more significant in determining water quality in relation to the studied variables; b) The nutrient (TKN and P) loads in impacted areas may be associated with point sources such as domestic wastewater discharges with inadequate treatment levels; and c) The presence of NO3- in impacted areas can be associated to the runoff, particularly in agricultural areas, where the application of fertilizers is common at certain times of the year.

Keywords: land use, linear regression, point and non-point pollution sources, streams, water resources management

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Authors: Sean Vincent

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Within the academic community, there is a consensus that political parties in established liberal democracies are facing a myriad of organisational challenges as a result of falling membership, weakening links to grass-roots support and rising voter apathy. During the same period of party decline and growing public disengagement political parties have become increasingly professionalised. The professionalisation of political parties owes much to changes in technology, with television becoming the dominant medium for political communication. In recent years, however, it has become clear that a new medium of communication is becoming utilised by political parties and candidates – New Media. New Media, a term hard to define but related to internet based communication, offers a potential revolution in political communication. It can be utilised by anyone with access to the internet and its most widely used platforms of communication such as Facebook and Twitter, are free to use. The advent of Web 2.0 has dramatically changed what can be done with the Internet. Websites now allow candidates at the constituency level to fundraise, organise and set out personalised policies. Social media allows them to communicate with supporters and potential voters practically cost-free. As such candidate dependency on the national party for resources and image now lies open to debate. Arguing that greater candidate independence may be a natural next step in light of the contemporary challenges faced by parties, this paper examines how New Media is being used by candidates at the constituency level to increase their personal vote. The paper will present findings from research carried out during two elections – the Japanese Lower House election of 2014 and the UK general election of 2015. During these elections a sample of candidates, totalling 150 candidates, from the three biggest parties in each country were selected and their new media output, specifically candidate websites, Twitter and Facebook output subjected to content analysis. The analysis examines how candidates are using new media to both become more functionally, through fundraising and volunteer mobilisation and politically, through the promotion of personal/local policies, independent from the national party. In order to validate the results of content analysis this paper will also present evidence from interviews carried out with 17 candidates that stood in the 2014 Japanese Lower House election or 2015 UK general election. With a combination of statistical analysis and interviews, several conclusions can be made about the use of New Media at constituency level. The findings show not just a clear difference in the way candidates from each country are using New Media but also differences within countries based upon the particular circumstances of each constituency. While it has not yet replaced traditional methods of fundraising and activist mobilisation, New Media is also becoming increasingly important in campaign organisation and the general consensus amongst candidates is that its importance will continue to grow along as politics in both countries becomes more diffuse.

Keywords: political campaigns, elections, new media, political communication

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Authors: Tsuiping Chen

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It has always been an international consensus that food forms a big part of any culture since the old times. However, this idea has not been globally concretized until the announcement of including food or cuisine as intangible cultural heritage by UNESCO in 2010. This announcement strengthens the value of food culture, which is getting more and more notice by every country. Although Taiwan is not one of the members of the United Nations, we cannot detach ourselves from this important global trend, especially when we have a lot of culinary students expected to join the world culinary job market. These students should have been well educated with the knowledge of world food culture to make them have the sensibility and perspectives for the occurring global food issues before joining the culinary jobs. Under the premise of the above concern, the researcher and also the instructor took on action research with one class of students in the 'Food Culture' course watching, discussing, and analyzing 12 culinary documentary films selected from one decade’s (2007-2016) of Berlin Culinary Cinema in one semester of class hours. In addition, after class, the students separated themselves into six groups and joined 12 times of one-hour-long focus group discussion on the 12 films conducted by the researcher. Furthermore, during the semester, the students submitted their reflection reports on each film to the university e-portfolio system. All the focus discussions and reflection reports were recorded and collected for further analysis by the researcher and one invited film researcher. Glaser and Strauss’ Grounded Theory (1967) constant comparison method was employed to analyze the collected data. Finally, the findings' results were audited by all participants of the research. All the participants and the researchers created 200 items of food culture products, 74 items of food culture practices, and 50 items of food culture perspectives from the action research journey through watching culinary documentaries. The journey did broaden students’ points of view on world food culture and enhance their capability on perspective construction for food culture. Four aspects of significant findings were demonstrated. First, learning food culture through watching Berlin culinary films helps students link themselves to the happening global food issues such as food security, food poverty, and food sovereignty, which direct them to rethink how people should grow, share and consume food. Second, watching different categories of documentary food films enhances students’ strong sense of responsibility for ensuring healthy lives and promoting well-being for all people in every corner of the world. Third, watching these documentary films encourages students to think if the culinary education they have accepted in this island is inclusive and the importance of quality education, which can promote lifelong learning. Last but not least, the journey of the culinary documentary film watching in the 'Food Culture' course inspires students to take pride in their profession. It is hoped the model of teaching food culture with culinary documentary films will inspire more food culture educators, researchers, and the culinary curriculum designers.

Keywords: food culture, action research, culinary documentary films, food culture products, practices, perspectives

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Authors: Obinna Benedict Duru

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This study focuses on the elderly and the challenges that confront them. The elderly are that particular segment of our population who by virtue of the aging process have attained the stage in most cases where they are confronted with the challenges of economic dependency and social marginality. These challenges are as a result of the physical and biological decline occasioned by social myths and realities which portray the elderly as a dependent population whose members could not and should not work and who need social assistance that the younger population is obliged to provide. From the moment of birth to the moment of death, our bodies are constantly changing. We are all enmeshed in the process of growing old, a transition from youthfulness to elderliness. In youth-oriented modern societies like ours, we tend to attach positive importance and significance to the biological changes that occur early in life and define later physical changes in negative terms. Children growing up and young adults receive more attention, greater responsibilities and more legal rights to reward them on their way. But few people are congratulated on getting old. We commiserate with people who are getting old and make jokes about their supposedly physical, mental and biological decline. Wrinkles, loss of weight and vitality are all parts of the aging process. In almost all parts of the world, earlier researches have shown that about fifty percent of the elderly who suffer from stroke, arthritis, senility and other age related diseases are the disengaged and neglected elderly. Rapid technological changes render the knowledge and skills of the elderly obsolete; education is geared toward the young and the generational competition for jobs leads to pressures on the elderly to retire. Control of initial resources are shifted to the middle-aged and older workers are pushed into positions of economic dependency. This study therefore, among other things tend to discover how some government policies have affected the elderly particularly in Africa. To discover the prospects and possibilities of the elderly for a better living. To make a comparison of the advances in healthcare giving made in the advanced western societies to the practice in Sub Saharan Africa etc. The hypotheses of this study include: that the elderly in Sub Saharan Africa are more vulnerable than their counterparts in Europe and America. The elderly are more prone to social isolation, and that the elderly are mostly affected by age-related sickness etc. With a survey method as the research design, and sample size of about 500 respondents,probability sampling technique was used. Data which were analyzed using chi-square and tables were collected through primary and secondary sources. The findings made include: that the elderly suffer pains of old age especially when disengaged from work or social activity. That loss of income condemn the elderly to a life of vegetable existence, and that those who do not have other means of re-integration usually see old age with regret and despair. It is therefore, recommended among other things that social welfare scheme and the process of re-integration at old age be introduced for the non pensionable elderly in Africa.

Keywords: elderly, social isolation, dependency, re-integration

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Authors: Vibol San, Vin Spoann

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Manufacturing plays an important role in job creation around the world. In 2013, it is estimated that there were more than half a billion jobs in manufacturing. In Cambodia in 2015, the primary industry occupies 26.18% of the total economy, while agriculture is contributing 29% and the service sector 39.43%. The number of industrial factories, which are dominated by garment and textiles, has increased since 1994, mainly in Phnom Penh city. Approximately 56% out of total 1302 firms are operated in the Capital city in Cambodia. Industrialization to achieve the economic growth and social development is directly responsible for environmental degradation, threatening the ecosystem and human health issues. About 96% of total firms in Phnom Penh city are the most and moderately polluting firms, which have contributed to environmental concerns. Despite an increasing array of laws, strategies and action plans in Cambodia, the Ministry of Environment has encountered some constraints in conducting the monitoring work, including lack of human and financial resources, lack of research documents, the limited analytical knowledge, and lack of technical references. Therefore, the necessary information on industrial pollution to set strategies, priorities and action plans on environmental protection issues is absent in Cambodia. In the absence of this data, effective environmental protection cannot be implemented. The objective of this study is to estimate industrial pollution load by employing the Industrial Pollution Projection System (IPPS), a rapid environmental management tool for assessment of pollution load, to produce a scientific rational basis for preparing future policy direction to reduce industrial pollution in Phnom Penh city. Due to lack of industrial pollution data in Phnom Penh, industrial emissions to the air, water and land as well as the sum of emissions to all mediums (air, water, land) are estimated using employment economic variable in IPPS. Due to the high number of employees, the total environmental load generated in Phnom Penh city is estimated to be 476.980.93 tons in 2014, which is the highest industrial pollution compared to other locations in Cambodia. The result clearly indicates that Phnom Penh city is the highest emitter of all pollutants in comparison with environmental pollutants released by other provinces. The total emission of industrial pollutants in Phnom Penh shares 55.79% of total industrial pollution load in Cambodia. Phnom Penh city generates 189,121.68 ton of VOC, 165,410.58 ton of toxic chemicals to air, 38,523.33 ton of toxic chemicals to land and 28,967.86 ton of SO2 in 2014. The results of the estimation show that Textile and Apparel sector is the highest generators of toxic chemicals into land and air, and toxic metals into land, air and water, while Basic Metal sector is the highest contributor of toxic chemicals to water. Textile and Apparel sector alone emits 436,015.84 ton of total industrial pollution loads. The results suggest that reduction in industrial pollution could be achieved by focusing on the most polluting sectors.

Keywords: most polluting area, polluting industry, pollution load, pollution intensity

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Authors: Monira Nazmi Jahan

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Child rape or child abuse is a serious and fearsome crime against children, which is an epidemic almost in every state of today’s world. However, in the case of Bangladesh, the scenario is terrifying. The objective of this paper is to examine the laws relating to child rape in Bangladesh as according to a renowned Daily Newspaper 'Prothom Alo', nearly 346 children are being raped since January 2019. This paper discusses and draws the difference of child rape provisions of Bangladesh with other South-Asian countries, comprises of India, Maldives, Pakistan, Sri Lanka, Nepal, Bhutan, and Afghanistan. In Bangladesh, girls below 18 years are considered to be a child. ‘The Penal Code, 1860’ and a special law ‘Nari O Shishu Nirjatan Daman Ain, 2012’ provides that any person committing child rape will be punished with rigorous life imprisonment and fine. This piece of law also gives provisions for punishment in case of child’s death after the commission of rape and gang rape, and the punishment is the death penalty. In India there is ‘The Protection of Children from Sexual Offences Act, 2012’ (POSCO) which has separate provisions for sexual assault, penetrative sexual assault and aggravated penetrative sexual assault by different categories of person such as relatives, institutional officers and trustees and also for mentally and physically challenged child victims and provides punishment up to death penalty. In Pakistan, there is ‘Pakistan Penal Code Amended Act, 2016’ which has only two provisions for child rape. In case offence committed by one person, the punishment is 10 to 25 years of imprisonment and fine. In case of offence committed by two or more persons, each shall be liable to death or imprisonment for life. Unfortunately, Afghanistan has no laws for the protection of rape victims of women let alone children, whereas there are a lot of child rape cases, including both girls and boys who are used for sexual slavery. The Maldives has a special law named ‘Special Provisions Act to Deal with Child Sex Abuse Offenders.’ This has categorized the offenders like POSCO and has provided punishments accordingly. The punishments are: punishments range from 1 to 25 years accordingly, whereas Bangladesh has lesser provisions, but the gravity and duration of punishments are much higher. The Penal Code of Sri Lanka imposes a minimum sentence of 10 years for those convicted of raping a child under 18 years. In Bhutan, child rape provision is made according to the age of a child. ‘The Penal Code of Bhutan, 2004’, mentions provisions for the rape of a child in case of child rape below and above 12 years, gang rape of a child below and above 12 years and has graded the punishments as first, second and third degree. Though Bangladesh has better provisions for punishments, the ages are not categorized in the laws. In Nepal there is ‘Act relating to Children, 2018’ provisions are made for offenders who use or cause or engage child sexual exploitation, and the punishment is same for rape offenders according to prevailing laws in Nepal. No separate punishments for child offenders are made. The ultimate conclusion that can be drawn is Bangladesh has better punishments than all other South-Asian countries and same punishment as India however, Bangladesh can make or amend the laws and categorize offenders as like POSCO of India, Special provisions of Maldives and Bhutan.

Keywords: child rape, death penalty, sexual slavery, South Asia

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Authors: Anatoliy A. Alabugin, Nikolay K. Topuzov, Sergei V. Aliukov

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It is well known, that while we do a quantitative evaluation of the quality control of some economic processes (in particular, resource saving) with help innovation factors, there are three groups of problems: high uncertainty of indicators of the quality management, their considerable ambiguity, and high costs to provide a large-scale research. These problems are defined by the use of contradictory objectives of enhancing of the quality control in accordance with innovation factors and preservation of economic stability of the enterprise. The most acutely, such factors are felt in the countries lagging behind developed economies of the world according to criteria of innovativeness and effectiveness of management of the resource saving. In our opinion, the following two methods for reconciling of the above-mentioned objectives and reducing of conflictness of the problems are to solve this task most effectively: 1) the use of paradigms and concepts of evolutionary improvement of quality of resource-saving management in the cycle "from the project of an innovative product (technology) - to its commercialization and update parameters of customer value"; 2) the application of the so-called integrative-cyclical approach which consistent with complexity and type of the concept, to studies allowing to get quantitative assessment of the stages of achieving of the consistency of these objectives (from baseline of imbalance, their compromise to achievement of positive synergies). For implementation, the following mathematical tools are included in the integrative-cyclical approach: index-factor analysis (to identify the most relevant factors); regression analysis of relationship between the quality control and the factors; the use of results of the analysis in the model of fuzzy sets (to adjust the feature space); method of non-parametric statistics (for a decision on the completion or repetition of the cycle in the approach in depending on the focus and the closeness of the connection of indicator ranks of disbalance of purposes). The repetition is performed after partial substitution of technical and technological factors ("hard") by management factors ("soft") in accordance with our proposed methodology. Testing of the proposed approach has shown that in comparison with the world practice there are opportunities to improve the quality of resource-saving management using innovation factors. We believe that the implementation of this promising research, to provide consistent management decisions for reducing the severity of the above-mentioned contradictions and increasing the validity of the choice of resource-development strategies in terms of parameters of quality management and sustainability of enterprise, is perspective. Our existing experience in the field of quality resource-saving management and the achieved level of scientific competence of the authors allow us to hope that the use of the integrative-cyclical approach to the study and evaluation of the resulting and factor indicators will help raise the level of resource-saving characteristics up to the value existing in the developed economies of post-industrial type.

Keywords: integrative-cyclical approach, quality control, evaluation, innovation factors. economic sustainability, innovation cycle of management, disbalance of goals of development

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Authors: Emmanuel O. Ezim, Idowu A. Olayinka, Michael Oladunjoye, Izuchukwu I. Obiadi

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Monitoring of reservoir properties prior to well placements and production is a requirement for optimisation and efficient oil and gas production. This is usually done using well log analyses and 3-D seismic, which are often prone to errors. However, 4-D (Time-lapse) seismic, incorporating numerous 3-D seismic surveys of the same field with the same acquisition parameters, which portrays the transient changes in the reservoir due to production effects over time, could be utilised because it generates better resolution. There is, however dearth of information on the applicability of this approach in the Niger Delta. This study was therefore designed to apply 4-D seismic, well-log and geologic data in monitoring of reservoirs in the EK field of the Niger Delta. It aimed at locating bypassed accumulations and ensuring effective reservoir management. The Field (EK) covers an area of about 1200km2 belonging to the early (18ma) Miocene. Data covering two 4-D vintages acquired over a fifteen-year interval were obtained from oil companies operating in the field. The data were analysed to determine the seismic structures, horizons, Well-to-Seismic Tie (WST), and wavelets. Well, logs and production history data from fifteen selected wells were also collected from the Oil companies. Formation evaluation, petrophysical analysis and inversion alongside geological data were undertaken using Petrel, Shell-nDi, Techlog and Jason Software. Well-to-seismic tie, formation evaluation and saturation monitoring using petrophysical and geological data and software were used to find bypassed hydrocarbon prospects. The seismic vintages were interpreted, and the amounts of change in the reservoir were defined by the differences in Acoustic Impedance (AI) inversions of the base and the monitor seismic. AI rock properties were estimated from all the seismic amplitudes using controlled sparse-spike inversion. The estimated rock properties were used to produce AI maps. The structural analysis showed the dominance of NW-SE trending rollover collapsed-crest anticlines in EK with hydrocarbons trapped northwards. There were good ties in wells EK 27, 39. Analysed wavelets revealed consistent amplitude and phase for the WST; hence, a good match between the inverted impedance and the good data. Evidence of large pay thickness, ranging from 2875ms (11420 TVDSS-ft) to about 2965ms, were found around EK 39 well with good yield properties. The comparison between the base of the AI and the current monitor and the generated AI maps revealed zones of untapped hydrocarbons as well as assisted in determining fluids movement. The inverted sections through EK 27, 39 (within 3101 m - 3695 m), indicated depletion in the reservoirs. The extent of the present non-uniform gas-oil contact and oil-water contact movements were from 3554 to 3575 m. The 4-D seismic approach led to better reservoir characterization, well development and the location of deeper and bypassed hydrocarbon reservoirs.

Keywords: reservoir monitoring, 4-D seismic, well placements, petrophysical analysis, Niger delta basin

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Authors: Torsten Hermanns, You Wang, Stefan Janssen, Markus Niessen, Christoph Schoeler, Ulrich Thombansen, Wolfgang Schulz

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In long pulse laser drilling of metals, it can be demonstrated that the ablation shape approaches a so-called asymptotic shape such that it changes only slightly or not at all with further irradiation. These findings are already known from ultra short pulse (USP) ablation of dielectric and semiconducting materials. The explanation for the occurrence of an asymptotic shape in long pulse drilling of metals is identified, a model for the description of the asymptotic hole shape numerically implemented, tested and clearly confirmed by comparison with experimental data. The model assumes a robust process in that way that the characteristics of the melt flow inside the arising melt film does not change qualitatively by changing the laser or processing parameters. Only robust processes are technically controllable and thus of industrial interest. The condition for a robust process is identified by a threshold for the mass flow density of the assist gas at the hole entrance which has to be exceeded. Within a robust process regime the melt flow characteristics can be captured by only one model parameter, namely the intensity threshold. In analogy to USP ablation (where it is already known for a long time that the resulting hole shape results from a threshold for the absorbed laser fluency) it is demonstrated that in the case of robust long pulse ablation the asymptotic shape forms in that way that along the whole contour the absorbed heat flux density is equal to the intensity threshold. The intensity threshold depends on the special material and radiation properties and has to be calibrated be one reference experiment. The model is implemented in a numerical simulation which is called AsymptoticDrill and requires such a few amount of resources that it can run on common desktop PCs, laptops or even smart devices. Resulting hole shapes can be calculated within seconds what depicts a clear advantage over other simulations presented in literature in the context of industrial every day usage. Against this background the software additionally is equipped with a user-friendly GUI which allows an intuitive usage. Individual parameters can be adjusted using sliders while the simulation result appears immediately in an adjacent window. A platform independent development allow a flexible usage: the operator can use the tool to adjust the process in a very convenient manner on a tablet during the developer can execute the tool in his office in order to design new processes. Furthermore, at the best knowledge of the authors AsymptoticDrill is the first simulation which allows the import of measured real beam distributions and thus calculates the asymptotic hole shape on the basis of the real state of the specific manufacturing system. In this paper the emphasis is placed on the investigation of the effect of multiple reflections on the asymptotic hole shape which gain in importance when drilling holes with large aspect ratios.

Keywords: asymptotic hole shape, intensity threshold, long pulse laser drilling, robust process

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Authors: Almudena Espin Perez, Tyler Risom, Carl Pelz, Isabel English, Robert M. Angelo, Rosalie Sears, Andrew J. Gentles

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Pancreatic ductal adenocarcinoma (PDAC) is one of the most deadly malignancies. The role of the tumor microenvironment (TME) is gaining significant attention in cancer research. Despite ongoing efforts, the nature of the interactions between tumors, immune cells, and stromal cells remains poorly understood. The cell-intrinsic properties that govern cell lineage plasticity in PDAC and extrinsic influences of immune populations require technically challenging approaches due to the inherently heterogeneous nature of PDAC. Understanding the cell lineage plasticity of PDAC will improve the development of novel strategies that could be translated to the clinic. Members of the team have demonstrated that the acquisition of ductal to neuroendocrine lineage plasticity in PDAC confers therapeutic resistance and is a biomarker of poor outcomes in patients. Our approach combines computational methods for deconvolving bulk transcriptomic cancer data using CIBERSORTx and high-throughput single-cell imaging using Multiplexed Ion Beam Imaging (MIBI) to study lineage plasticity in PDAC and its relationship to the infiltrating immune system. The CIBERSORTx algorithm uses signature matrices from immune cells and stroma from sorted and single-cell data in order to 1) infer the fractions of different immune cell types and stromal cells in bulked gene expression data and 2) impute a representative transcriptome profile for each cell type. We studied a unique set of 300 genomically well-characterized primary PDAC samples with rich clinical annotation. We deconvolved the PDAC transcriptome profiles using CIBERSORTx, leveraging publicly available single-cell RNA-seq data from normal pancreatic tissue and PDAC to estimate cell type proportions in PDAC, and digitally reconstruct cell-specific transcriptional profiles from our study dataset. We built signature matrices and optimized by simulations and comparison to ground truth data. We identified cell-type-specific transcriptional programs that contribute to cancer cell lineage plasticity, especially in the ductal compartment. We also studied cell differentiation hierarchies using CytoTRACE and predict cell lineage trajectories for acinar and ductal cells that we believe are pinpointing relevant information on PDAC progression. Collaborators (Angelo lab, Stanford University) has led the development of the Multiplexed Ion Beam Imaging (MIBI) platform for spatial proteomics. We will use in the very near future MIBI from tissue microarray of 40 PDAC samples to understand the spatial relationship between cancer cell lineage plasticity and stromal cells focused on infiltrating immune cells, using the relevant markers of PDAC plasticity identified from the RNA-seq analysis.

Keywords: deconvolution, imaging, microenvironment, PDAC

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Authors: Fabrizio Ascione, Martina Borrelli, Rosa Francesca De Masi, Silvia Ruggiero, Giuseppe Peter Vanoli

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The Directive 2010/31/EC 'Directive of the European Parliament and of the Council of 19 may 2010 on the energy performance of buildings' moved the targets of the previous version toward more ambitious targets, for instance by establishing that, by 31 December 2020, all new buildings should demand nearly zero-energy. Moreover, the demonstrative role of public buildings is strongly affirmed so that also the target nearly zero-energy buildings is anticipated, in January 2019. On the other hand, given the very low turn-over rate of buildings (in Europe, it ranges between 1-3%/yearly), each policy that does not consider the renovation of the existing building stock cannot be effective in the short and medium periods. According to this proposal, the study provides a novel, holistic approach to design the refurbishment of educational buildings in colder cities of Mediterranean regions enabling stakeholders to understand the uncertainty to use numerical modelling and the real environmental and economic impacts of adopting some energy efficiency technologies. The case study is a university building of Molise region in the centre of Italy. The proposed approach is based on the application of the cost-optimal methodology as it is shown in the Delegate Regulation 244/2012 and Guidelines of the European Commission, for evaluating the cost-optimal level of energy performance with a macroeconomic approach. This means that the refurbishment scenario should correspond to the configuration that leads to lowest global cost during the estimated economic life-cycle, taking into account not only the investment cost but also the operational costs, linked to energy consumption and polluting emissions. The definition of the reference building has been supported by various in-situ surveys, investigations, evaluations of the indoor comfort. Data collection can be divided into five categories: 1) geometrical features; 2) building envelope audit; 3) technical system and equipment characterization; 4) building use and thermal zones definition; 5) energy building data. For each category, the required measures have been indicated with some suggestions for the identifications of spatial distribution and timing of the measurements. With reference to the case study, the collected data, together with a comparison with energy bills, allowed a proper calibration of a numerical model suitable for the hourly energy simulation by means of EnergyPlus. Around 30 measures/packages of energy, efficiency measure has been taken into account both on the envelope than regarding plant systems. Starting from results, two-point will be examined exhaustively: (i) the importance to use validated models to simulate the present performance of building under investigation; (ii) the environmental benefits and the economic implications of a deep energy refurbishment of the educational building in cold climates.

Keywords: energy simulation, modelling calibration, cost-optimal retrofit, university building

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Authors: A. T. Al-Isawi, P. E. F. Collins

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The behaviour of structures exposed to fire after an earthquake is not a new area of engineering research, but there remain a number of areas where further work is required. Such areas relate to the way in which seismic excitation is applied to a structure, taking into account the effect of soil-structure interaction (SSI) and the method of analysis, in addition to identifying the excitation load properties. The selection of earthquake data input for use in nonlinear analysis and the method of analysis are still challenging issues. Thus, realistic artificial ground motion input data must be developed to certify that site properties parameters adequately describe the effects of the nonlinear inelastic behaviour of the system and that the characteristics of these parameters are coherent with the characteristics of the target parameters. Conversely, ignoring the significance of some attributes, such as frequency content, soil site properties and earthquake parameters may lead to misleading results, due to the misinterpretation of required input data and the incorrect synthesise of analysis hypothesis. This paper presents a study of the post-earthquake fire (PEF) performance of a multi-storey steel-framed building resting on soft clay, taking into account the effects of the nonlinear inelastic behaviour of the structure and soil, and the soil-structure interaction (SSI). Structures subjected to an earthquake may experience various levels of damage; the geometrical damage, which indicates the change in the initial structure’s geometry due to the residual deformation as a result of plastic behaviour, and the mechanical damage which identifies the degradation of the mechanical properties of the structural elements involved in the plastic range of deformation. Consequently, the structure presumably experiences partial structural damage but is then exposed to fire under its new residual material properties, which may result in building failure caused by a decrease in fire resistance. This scenario would be more complicated if SSI was also considered. Indeed, most earthquake design codes ignore the probability of PEF as well as the effect that SSI has on the behaviour of structures, in order to simplify the analysis procedure. Therefore, the design of structures based on existing codes which neglect the importance of PEF and SSI can create a significant risk of structural failure. In order to examine the criteria for the behaviour of a structure under PEF conditions, a two-dimensional nonlinear elasto-plastic model is developed using ABAQUS software; the effects of SSI are included. Both geometrical and mechanical damages have been taken into account after the earthquake analysis step. For comparison, an identical model is also created, which does not include the effects of soil-structure interaction. It is shown that damage to structural elements is underestimated if SSI is not included in the analysis, and the maximum percentage reduction in fire resistance is detected in the case when SSI is included in the scenario. The results are validated using the literature.

Keywords: Abaqus Software, Finite Element Analysis, post-earthquake fire, seismic analysis, soil-structure interaction

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Authors: Ahmad Saadiq, Neeraj Sahu

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Sediment, which comprises of solid particles of mineral and organic material are transported by water. In river systems, the amount of sediment transported is controlled by both the transport capacity of the flow and the supply of sediment. The transport of sediment in rivers is important with respect to pollution, channel navigability, reservoir ageing, hydroelectric equipment longevity, fish habitat, river aesthetics and scientific interests. The sediment load transported in a river is a very complex hydrological phenomenon. Hence, sediment transport has attracted the attention of engineers from various aspects, and different methods have been used for its estimation. So, several experimental equations have been submitted by experts. Though the results of these methods have considerable differences with each other and with experimental observations, because the sediment measures have some limits, these equations can be used in estimating sediment load. In this present study, two black box models namely, an SRC (Sediment Rating Curve) and ANN (Artificial Neural Network) are used in the simulation of the suspended sediment load. The study is carried out for Seonath subbasin. Seonath is the biggest tributary of Mahanadi river, and it carries a vast amount of sediment. The data is collected for Jondhra hydrological observation station from India-WRIS (Water Resources Information System) and IMD (Indian Meteorological Department). These data include the discharge, sediment concentration and rainfall for 10 years. In this study, sediment load is estimated from the input parameters (discharge, rainfall, and past sediment) in various combination of simulations. A sediment rating curve used the water discharge to estimate the sediment concentration. This estimated sediment concentration is converted to sediment load. Likewise, for the application of these data in ANN, they are normalised first and then fed in various combinations to yield the sediment load. RMSE (root mean square error) and R² (coefficient of determination) between the observed load and the estimated load are used as evaluating criteria. For an ideal model, RMSE is zero and R² is 1. However, as the models used in this study are black box models, they don’t carry the exact representation of the factors which causes sedimentation. Hence, a model which gives the lowest RMSE and highest R² is the best model in this study. The lowest values of RMSE (based on normalised data) for sediment rating curve, feed forward back propagation, cascade forward back propagation and neural network fitting are 0.043425, 0.00679781, 0.0050089 and 0.0043727 respectively. The corresponding values of R² are 0.8258, 0.9941, 0.9968 and 0.9976. This implies that a neural network fitting model is superior to the other models used in this study. However, a drawback of neural network fitting is that it produces few negative estimates, which is not at all tolerable in the field of estimation of sediment load, and hence this model can’t be crowned as the best model among others, based on this study. A cascade forward back propagation produces results much closer to a neural network model and hence this model is the best model based on the present study.

Keywords: artificial neural network, Root mean squared error, sediment, sediment rating curve

Procedia PDF Downloads 323

Authors: Sami Houry

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Complex systems exhibit universal characteristics as they near a tipping point. Among them are common generic early warning signals which precede critical transitions. These signals include: critical slowing down in which the rate of recovery from perturbations decreases over time; an increase in the variance of the state variable; an increase in the skewness of the state variable; an increase in the autocorrelations of the state variable; flickering between different states; and an increase in spatial correlations over time. The presence of the signals has management implications, as the identification of the signals near the tipping point could allow management to identify intervention points. Despite the applications of the generic early warning signals in various scientific fields, such as fisheries, ecology and finance, a review of literature did not identify any applications that address the program student withdrawal problem at the undergraduate distance universities. This area could benefit from the application of generic early warning signals as the program withdrawal rate amongst distance students is higher than the program withdrawal rate at face-to-face conventional universities. This research specifically assessed the generic early warning signals through an intensive case study of undergraduate program student withdrawal at a Canadian distance university. The university is non-cohort based due to its system of continuous course enrollment where students can enroll in a course at the beginning of every month. The assessment of the signals was achieved through the comparison of the incidences of generic early warning signals among students who withdrew or simply became inactive in their undergraduate program of study, the true positives, to the incidences of the generic early warning signals among graduates, the false positives. This was achieved through significance testing. Research findings showed support for the signal pertaining to the rise in flickering which is represented in the increase in the student’s non-pass rates prior to withdrawing from a program; moderate support for the signals of critical slowing down as reflected in the increase in the time a student spends in a course; and moderate support for the signals on increase in autocorrelation and increase in variance in the grade variable. The findings did not support the signal on the increase in skewness of the grade variable. The research also proposes a new signal based on the fractal-like characteristic of student behavior. The research also sought to extend knowledge by investigating whether the emergence of a program withdrawal status is self-similar or fractal-like at multiple levels of observation, specifically the program level and the course level. In other words, whether the act of withdrawal at the program level is also present at the course level. The findings moderately supported self-similarity as a potential signal. Overall, the assessment of the signals suggests that the signals, with the exception with the increase of skewness, could be utilized as a predictive management tool and potentially add one more tool, the fractal-like characteristic of withdrawal, as an additional signal in addressing the student program withdrawal problem.

Keywords: critical transitions, fractals, generic early warning signals, program student withdrawal

Procedia PDF Downloads 184

Authors: A. Almurshedi, M. Atherton, C. Mares, T. Stolarski, M. Miyatake

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Transportation and handling of delicate and lightweight objects is currently a significant issue in some industries. Two common contactless movement prototype designs, ultrasonic transducer design and vibrating plate design, are compared. Both designs are based on the method of squeeze-film levitation, and this study aims to identify the limitations, and challenges of each. The designs are evaluated in terms of levitation capabilities, and characteristics. To this end, theoretical and experimental explorations are made. It is demonstrated that the ultrasonic transducer prototype design is better suited to the terms of levitation capabilities. However, the design has some operating and mechanical designing difficulties. For making accurate industrial products in micro-fabrication and nanotechnology contexts, such as semiconductor silicon wafers, micro-components and integrated circuits, non-contact oil-free, ultra-precision and low wear transport along the production line is crucial for enabling. One of the designs (design A) is called the ultrasonic chuck, for which an ultrasonic transducer (Langevin, FBI 28452 HS) comprises the main part. Whereas the other (design B), is a vibrating plate design, which consists of a plain rectangular plate made of Aluminium firmly fastened at both ends. The size of the rectangular plate is 200x100x2 mm. In addition, four rounded piezoelectric actuators of size 28 mm diameter with 0.5 mm thickness are glued to the underside of the plate. The vibrating plate is clamped at both ends in the horizontal plane through a steel supporting structure. In addition, the dynamic of levitation using the designs (A and B) has been investigated based on the squeeze film levitation (SFL). The input apparatus that is used with designs consist of a sine wave signal generator connected to an amplifier type ENP-1-1U (Echo Electronics). The latter has to be utilised to magnify the sine wave voltage that is produced by the signal generator. The measurements of the maximum levitation for three different semiconductor wafers of weights 52, 70 and 88 [g] for design A are 240, 205 and 187 [um], respectively. Whereas the physical results show that the average separation distance for a disk of 5 [g] weight for design B reaches 70 [um]. By using the methodology of squeeze film levitation, it is possible to hold an object in a non-contact manner. The analyses of the investigation outcomes signify that the non-contact levitation of design A provides more improvement than design B. However, design A is more complicated than design B in terms of its manufacturing. In order to identify an adequate non-contact SFL design, a comparison between two common such designs has been adopted for the current investigation. Specifically, the study will involve making comparisons in terms of the following issues: floating component geometries and material type constraints; final created pressure distributions; dangerous interactions with the surrounding space; working environment constraints; and complication and compactness of the mechanical design. Considering all these matters is essential for proficiently distinguish the better SFL design.

Keywords: ANSYS, floating, piezoelectric, squeeze-film

Procedia PDF Downloads 148

Authors: Rosa Palmeri, Julieta I. Monteleone, Antonio C. Barbera, Carmelo Maucieri, Aldo Todaro, Virgilio Giannone, Giovanni Spagna

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In recent years, considerable interest has been shown in the functional properties of foods, and a relevant role has been played by phenolic compounds, able to scavenge free radicals. A more sustainable agriculture has to emerge to guarantee food supply over the next years. Wheat, corn, and rice are the most common cereals cultivated, but also other cereal species, such as barley can be appreciated for their peculiarities. Barley (Hordeum vulgare L.) is a C3 winter cereal that shows high resistance at drought and salt stresses. There are growing interests in barley as ingredient for the production of functional foods due to its high content of phenolic compounds and Beta-glucans. In this respect, the possibility of separating specific functional fractions from food industry by-products looks very promising. Olive leaves represent a quantitatively significant by-product of olive grove farming, and are an interesting source of phenolic compounds. In particular, oleuropein, which provide important nutritional benefits, is the main phenolic compound in olive leaves and ranges from 17% to 23% depending upon the cultivar and growing season period. Together with oleuropein and its derivatives (e.g. dimethyloleuropein, oleuropein diglucoside), olive leaves further contain tyrosol, hydroxytyrosol, and a series of secondary metabolities structurally related to them: verbascoside, ligstroside, hydroxytyrosol glucoside, tyrosol glucoside, oleuroside, oleoside-11-methyl ester, and nuzhenide. Several flavonoids, flavonoid glycosides, and phenolic acids have also described in olive leaves. The aim of this work was the production of functional food with higher content of polyphenols and the evaluation of their shelf life. Organic durum wheat and barley grains contain higher levels of phenolic compounds were used for the production of crackers. Olive leaf extract (OLE) was obtained from cv. ‘Biancolilla’ by aqueous extraction method. Two baked goods trials were performed with both organic durum wheat and barley flours, adding olive leaf extract. Control crackers, made as comparison, were produced with the same formulation replacing OLE with water. Total phenolic compound, moisture content, activity water, and textural properties at different time of storage were determined to evaluate the shelf-life of the products. Our the preliminary results showed that the enriched crackers showed higher phenolic content and antioxidant activity than control. Alternative uses of olive leaf extracts for crackers production could represent a good candidate for the addition of functional ingredients because bakery items are daily consumed, and have long shelf-life.

Keywords: barley, functional foods, olive leaf, polyphenols, shelf life

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Authors: Nur Rafeeda Daut

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The significance of this paper is to provide an insight on the role of social movement in building stronger ethnic relations in Malaysia. In particular, it focuses on how the BERSIH movement have been able to bring together the different ethnic groups in Malaysia to resist the present political administration that is seen to manipulate the electoral process and oppress the basic freedom of expression of Malaysians. Attention is given on how and why this group emerged and its mobilisation strategies. Malaysia which is a multi-ethnic and multi-religious society gained its independence from the British in 1957. Like many other new nations, it faces the challenges of nation building and governance. From economic issues to racial and religious tension, Malaysia is experiencing high level of corruption and income disparity among the different ethnic groups. The political parties in Malaysia are also divided along ethnic lines. BERSIH which is translated as ‘clean’ is a movement which seeks to reform the current electoral system in Malaysia to ensure equality, justice, free and fair elections. It was originally formed in 2007 as a joint committee that comprised leaders from political parties, civil society groups and NGOs. In April 2010, the coalition developed as an entirely civil society movement unaffiliated to any political party. BERSIH claimed that the electoral roll in Malaysia has been marred by fraud and other irregularities. In 2015, the BERSIH movement organised its biggest rally in Malaysia which also includes 38 other rallies held internationally. Supporters of BERSIH that participated in the demonstration were comprised of all the different ethnic groups in Malaysia. In this paper, two social movement theories are used: resource mobilization theory and political opportunity structure to explain the emergence and mobilization of the BERSIH movement in Malaysia. Based on these two theories, corruption which is believed to have contributed to the income disparity among Malaysians has generated the development of this movement. The rise of re-islamisation values propagated by certain groups in Malaysia and the shift in political leadership has also created political opportunities for this movement to emerge. In line with the political opportunity structure theory, the BERSIH movement will continue to create more opportunities for the empowerment of civil society and the unity of ethnic relations in Malaysia. Comparison is made on the degree of ethnic unity in the country before and after BERSIH was formed. This would include analysing the level of re-islamisation values and also the level of corruption in relation to economic income under the premiership of the former Prime Minister Mahathir and the present Prime Minister Najib Razak. The country has never seen such uprisings like BERSIH where ethnic groups which over the years have been divided by ethnic based political parties and economic disparity joined together with a common goal for equality and fair elections. As such, the BERSIH movement is a unique case where it illustrates the change of political landscape, ethnic relations and civil society in Malaysia.

Keywords: ethnic relations, Malaysia, political opportunity structure, resource mobilization theory and social movement

Procedia PDF Downloads 346

Authors: Diego F. Carrillo-González, Milena Osorio, Natalia M. Cerro, Yasser Y. Lenis

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Introduction: mortality during the implantation and early embryonic development periods reach around 30% in different mammalian species. It has been described that progesterone (P4) and Arginine (Arg) play a beneficial role in establishing and maintaining early pregnancy in mammals. The combined effect between Arg and P4 on reproductive parameters in the rabbit species is not yet elucidated, to our best knowledge. Objective: to assess the effect of L-arginine and progesterone during the post-breeding period in female rabbits on the composition of the amniotic fluid, the placental structure, and the bone growth in their fetuses. Methods: crossbred female rabbits (n=16) were randomly distributed into four experimental groups (Ctrl, Arg, P4, and Arg+P4). In the control group, 0.9% saline solution was administered as a placebo, the Arg group was administered arginine (50 mg/kg BW) from day 4.5 to day 19 post-breeding, the P4 group was administered progesterone (Gestavec®, 1.5 mg/kg BW) from 24 hours to day 4 post-breeding and for the Arg+P4 group, an administration was performed under the same time and dose guidelines as the Arg and P4 treatments. Four females were sacrificed, and the amniotic fluid was collected and analyzed with rapid urine test strips, while the placenta and fetuses were processed in the laboratory to obtain histological plates. The percentage of deciduous, labyrinthine, and junctional zones was determined, and the length of the femur for each fetus was measured as an indicator of growth. Descriptive statistics were applied to identify the success rates for each of the tests. Afterwards, A one-way analysis of variance (ANOVA) was performed, and a comparison of means was conducted by Tukey's test. Results: a higher density (p<0.05) was observed in the amniotic fluid for fetuses in the control group (1022±2.5g/mL) compared to the P4 (1015±5.3g/mL) and Arg+P4 (1016±4,9g/mL) groups. Additionally, the density of amniotic fluid in the Arg group (1021±2.5g/mL) was higher (p<0.05) than in the P4 group. The concentration of protein, glucose, and ascorbic acid had no statistical difference between treatments (p>0.05). The histological analysis of the uteroplacental regions, a statistical difference (p<0,05) in the proportion of deciduous zone was found between the P4 group (9.6±2.6%) when compared with the Ctrl (28.15±12.3%), and Arg+P4 (26.3±4.9) groups. In the analysis of the fetuses, the weight was higher for the Arg group (2.69±0.18), compared to the other groups (p<0.05), while a shorter length was observed (p<0.05) in the fetuses for the Arg+P4 group (25.97±1.17). However, no difference (p>0.05) was found when comparing the length of the developing femurs between the experimental groups. Conclusion: the combination of L-arginine and progesterone allows a reduction in the density of amniotic fluid, without affecting the protein, energy, and antioxidant components. However, the use of L-arginine stimulates weight gain in fetuses, without affecting size, which could be used to improve production parameters in rabbit production systems. In addition, the modification in the deciduous zone could show a placental adaptation based on the fetal growth process, however more specific studies on the placentation process are required.

Keywords: arginine, progesterone, rabbits, reproduction

Procedia PDF Downloads 87

Authors: Ofelia Loani Elvir Lazo, Roya Yumul, Sevan Komshian, Ruby Wang, Jun Tang

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Background: Monitoring the anti-nociceptive drug effect is useful because a sudden and strong nociceptive stimulus may result in untoward autonomic responses and muscular reflex movements. Monitoring the anti-nociceptive effects of perioperative medications has long been desiredas a way to provide anesthesiologists information regarding a patient’s level of antinociception and preclude any untoward autonomic responses and reflexive muscular movements from painful stimuli intraoperatively.To this end, electroencephalogram (EEG) based tools includingBIS and qCON were designed to provide information about the depth of sedation whileqNOXwas produced to informon the degree of antinociception.The goal of this study was to compare the reliability of qCON/qNOX to BIS asspecific indicators of response to nociceptive stimulation. Methods: Sixty-two patients undergoing general anesthesia with LMA were included in this study. Institutional Review Board(IRB) approval was obtained, and informed consent was acquired prior to patient enrollment. Inclusion criteria included American Society of Anesthesiologists (ASA) class I-III, 18 to 80 years of age, and either gender. Exclusion criteria included the inability to consent. Withdrawal criteria included conversion to endotracheal tube and EEG malfunction. BIS and qCON/qNOX electrodes were simultaneously placed o62n all patientsprior to induction of anesthesia and were monitored throughout the case, along with other perioperative data, including patient response to noxious stimuli. All intraoperative decisions were made by the primary anesthesiologist without influence from qCON/qNOX. Student’s t-distribution, prediction probability (PK), and ANOVA were used to statistically compare the relative ability to detect nociceptive stimuli for each index. Twenty patients were included for the preliminary analysis. Results: A comparison of overall intraoperative BIS, qCON and qNOX indices demonstrated no significant difference between the three measures (N=62, p> 0.05). Meanwhile, index values for qNOX (62±18) were significantly higher than those for BIS (46±14) and qCON (54±19) immediately preceding patient responses to nociceptive stimulation in a preliminary analysis (N=20, * p= 0.0408). Notably, certain hemodynamic measurements demonstrated a significant increase in response to painful stimuli (MAP increased from74±13 mm Hg at baseline to 84± 18 mm Hg during noxious stimuli [p= 0.032] and HR from 76±12 BPM at baseline to 80±13BPM during noxious stimuli[p=0.078] respectively). Conclusion: In this observational study, BIS and qCON/qNOX provided comparable information on patients’ level of sedation throughout the course of an anesthetic. Meanwhile, increases in qNOX values demonstrated a superior correlation to an imminent response to stimulation relative to all other indices.

Keywords: antinociception, bispectral index (BIS), general anesthesia, laryngeal mask airway, qCON/qNOX

Procedia PDF Downloads 91

Authors: A. Abdouni, C. Thieulin, M. Djaghloul, R. Vargiolu, H. Zahouani

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A decline in the main sensory modalities (vision, hearing, taste, and smell) is well reported to occur with advancing age, it is expected a similar change to occur with touch sensation and perception. In this study, we have focused on the touch sensations highlighting ageing and gender influences with in vivo systems. The touch process can be divided into two main phases: The first phase is the first contact between the finger and the object, during this contact, an adhesive force has been created which is the needed force to permit an initial movement of the finger. In the second phase, the finger mechanical properties with their surface topography play an important role in the obtained sensation. In order to understand the age and gender effects on the touch sense, we develop different ideas and systems for each phase. To better characterize the contact, the mechanical properties and the surface topography of human finger, in vivo studies on the pulp of 40 subjects (20 of each gender) of four age groups of 26±3, 35+-3, 45+-2 and 58±6 have been performed. To understand the first touch phase a classical indentation system has been adapted to measure the finger contact properties. The normal force load, the indentation speed, the contact time, the penetration depth and the indenter geometry have been optimized. The penetration depth of a glass indenter is recorded as a function of the applied normal force. Main assessed parameter is the adhesive force F_ad. For the second phase, first, an innovative approach is proposed to characterize the dynamic finger mechanical properties. A contactless indentation test inspired from the techniques used in ophthalmology has been used. The test principle is to blow an air blast to the finger and measure the caused deformation by a linear laser. The advantage of this test is the real observation of the skin free return without any outside influence. Main obtained parameters are the wave propagation speed and the Young's modulus E. Second, negative silicon replicas of subject’s fingerprint have been analyzed by a probe laser defocusing. A laser diode transmits a light beam on the surface to be measured, and the reflected signal is returned to a set of four photodiodes. This technology allows reconstructing three-dimensional images. In order to study the age and gender effects on the roughness properties, a multi-scale characterization of roughness has been realized by applying continuous wavelet transform. After determining the decomposition of the surface, the method consists of quantifying the arithmetic mean of surface topographic at each scale SMA. Significant differences of the main parameters are shown with ageing and gender. The comparison between men and women groups reveals that the adhesive force is higher for women. The results of mechanical properties show a Young’s modulus higher for women and also increasing with age. The roughness analysis shows a significant difference in function of age and gender.

Keywords: ageing, finger, gender, touch

Procedia PDF Downloads 264

Authors: María Canal-Rodríguez, María Arnaiz, Natalia Rey-Raap, Ana Arenillas, Jon Ajuria

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The constant demand of electrical energy, as well as the increase in environmental concern, lead to the necessity of investing in clean and eco-friendly energy sources that implies the development of enhanced energy storage devices. Li-ion batteries (LIBs) and Electrical double layer capacitors (EDLCs) are the most widespread energy systems. Batteries are able to storage high energy densities contrary to capacitors, which main strength is the high-power density supply and the long cycle life. The combination of both technologies gave rise to Li-ion capacitors (LICs), which offers all these advantages in a single device. This is achieved combining a capacitive, supercapacitor-like positive electrode with a faradaic, battery-like negative electrode. Due to the abundance and affordability, dual carbon-based LICs are nowadays the common technology. Normally, an Active Carbon (AC) is used as the EDLC like electrode, while graphite is the material commonly employed as anode. LICs are potential systems to be used in applications in which high energy and power densities are required, such us kinetic energy recovery systems. Although these devices are already in the market, some drawbacks like the limited power delivered by graphite or the energy limiting nature of AC must be solved to trigger their used. Focusing on the anode, one possibility could be to replace graphite with Hard Carbon (HC). The better rate capability of the latter increases the power performance of the device. Moreover, the disordered carbonaceous structure of HCs enables storage twice the theoretical capacity of graphite. With respect to the cathode, the ACs are characterized for their high volume of micropores, in which the charge is storage. Nevertheless, they normally do not show mesoporous, which are really important mainly at high C-rates as they act as transport channels for the ions to reach the micropores. Usually, the porosity of ACs cannot be tailored, as it strongly depends on the precursor employed to get the final carbon. Moreover, they are not characterized for having a high electrical conductivity, which is an important characteristic to get a good performance in energy storage applications. A possible candidate to substitute ACs are carbon aerogels (CAs). CAs are materials that combine a high porosity with great electrical conductivity, opposite characteristics in carbon materials. Furthermore, its porous properties can be tailored quite accurately according to with the requirements of the application. In the present study, CAs with controlled porosity were obtained from polymerization of resorcinol and formaldehyde by microwave heating. Varying the synthesis conditions, mainly the amount of precursors and pH of the precursor solution, carbons with different textural properties were obtained. The way the porous characteristics affect the performance of the cathode was studied by means of a half-cell configuration. The material with the best performance was evaluated as cathode in a LIC versus a hard carbon as anode. An analogous full LIC made by a high microporous commercial cathode was also assembled for comparison purposes.

Keywords: li-ion capacitors, energy storage, tailored porosity, carbon aerogels

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Authors: Qian Chen, Lin Xu, Ping Ju, Zhuoran Li, Yiping Yu, Yuqing Jin

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The operation of power grid is becoming more and more complex and difficult due to its rapid development towards high voltage, long distance, and large capacity. For instance, many large-scale wind farms have connected to power grid, where their fluctuation and randomness is very likely to affect the stability and safety of the grid. Fortunately, many new-type equipments based on power electronics have been applied to power grid, such as UPFC (Unified Power Flow Controller), TCSC (Thyristor Controlled Series Compensation), STATCOM (Static Synchronous Compensator) and so on, which can help to deal with the problem above. Compared with traditional equipment such as generator, new-type controllable devices, represented by the FACTS (Flexible AC Transmission System), have more accurate control ability and respond faster. But they are too expensive to use widely. Therefore, on the basis of the comparison and analysis of the controlling characteristics between traditional control equipment and new-type controllable equipment in both time and space scale, a coordinated optimizing control method within mutil-time-space frame is proposed in this paper to bring both kinds of advantages into play, which can better both control ability and economical efficiency. Firstly, the coordination of different space sizes of grid is studied focused on the fluctuation caused by large-scale wind farms connected to power grid. With generator, FSC (Fixed Series Compensation) and TCSC, the coordination method on two-layer regional power grid vs. its sub grid is studied in detail. The coordination control model is built, the corresponding scheme is promoted, and the conclusion is verified by simulation. By analysis, interface power flow can be controlled by generator and the specific line power flow between two-layer regions can be adjusted by FSC and TCSC. The smaller the interface power flow adjusted by generator, the bigger the control margin of TCSC, instead, the total consumption of generator is much higher. Secondly, the coordination of different time sizes is studied to further the amount of the total consumption of generator and the control margin of TCSC, where the minimum control cost can be acquired. The coordination method on two-layer ultra short-term correction vs. AGC (Automatic Generation Control) is studied with generator, FSC and TCSC. The optimal control model is founded, genetic algorithm is selected to solve the problem, and the conclusion is verified by simulation. Finally, the aforementioned method within multi-time-space scale is analyzed with practical cases, and simulated on PSASP (Power System Analysis Software Package) platform. The correctness and effectiveness are verified by the simulation result. Moreover, this coordinated optimizing control method can contribute to the decrease of control cost and will provide reference to the following studies in this field.

Keywords: FACTS, multi-space-time frame, optimal control, TCSC

Procedia PDF Downloads 265

Authors: Alessandra Aparecida Vieira França, Adriana de Paula Lacerda Santos, Mauro Lacerda Santos Filho

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The purpose of this research i to study the behavior of precast prestressed hollow core slabs subjected to shear. In order to achieve this goal, shear tests were performed using hollow core slabs 26,5cm thick, with and without a concrete cover of 5 cm, without cores filled, with two cores filled and three cores filled with concrete. The tests were performed according to the procedures recommended by FIP (1992), the EN 1168:2005 and following the method presented in Costa (2009). The ultimate shear strength obtained within the tests was compared with the values of theoretical resistant shear calculated in accordance with the codes, which are being used in Brazil, noted: NBR 6118:2003 and NBR 14861:2011. When calculating the shear resistance through the equations presented in NBR 14861:2011, it was found that provision is much more accurate for the calculation of the shear strength of hollow core slabs than the NBR 6118 code. Due to the large difference between the calculated results, even for slabs without cores filled, the authors consulted the committee that drafted the NBR 14861:2011 and found that there is an error in the text of the standard, because the coefficient that is suggested, actually presents the double value than the needed one! The ABNT, later on, soon issued an amendment of NBR 14861:2011 with the necessary corrections. During the tests for the present study, it was confirmed that the concrete filling the cores contributes to increase the shear strength of hollow core slabs. But in case of slabs 26,5 cm thick, the quantity should be limited to a maximum of two cores filled, because most of the results for slabs with three cores filled were smaller. This confirmed the recommendation of NBR 14861:2011which is consistent with standard practice. After analyzing the configuration of cracking and failure mechanisms of hollow core slabs during the shear tests, strut and tie models were developed representing the forces acting on the slab at the moment of rupture. Through these models the authors were able to calculate the tensile stress acting on the concrete ties (ribs) and scaled the geometry of these ties. The conclusions of the research performed are the experiments results have shown that the mechanism of failure of the hollow-core slabs can be predicted using the strut-and-tie procedure, within a good range of accuracy. In addition, the needed of the correction of the Brazilian standard to review the correction factor σcp duplicated (in NBR14861/2011), and the limitation of the number of cores (Holes) to be filled with concrete, to increase the strength of the slab for the shear resistance. It is also suggested the increasing the amount of test results with 26.5 cm thick, and a larger range of thickness slabs, in order to obtain results of shear tests with cores concreted after the release of prestressing force. Another set of shear tests on slabs must be performed in slabs with cores filled and cover concrete reinforced with welded steel mesh for comparison with results of theoretical values calculated by the new revision of the standard NBR 14861:2011.

Keywords: prestressed hollow core slabs, shear, strut, tie models

Procedia PDF Downloads 332

Authors: Quentin C.P. Bourgogne, Vanessa Bouchart, Pierre Chevrier, Emmanuel Dattoli

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This study presents an experimental and theoretical work conducted on a PolyPhenylene Sulfide reinforced with 40%wt of short glass fibers (PPS GF40) and its matrix. Thermoplastics are widely used in the automotive industry to lightweight automotive parts. The replacement of metallic parts by thermoplastics is reaching under-the-hood parts, near the engine. In this area, the parts are subjected to high temperatures and are immersed in cooling liquid. This liquid is composed of water and glycol and can affect the mechanical properties of the composite. The aim of this work was thus to quantify the evolution of mechanical properties of the thermoplastic composite, as a function of temperature and liquid aging effects, in order to develop a reliable design of parts. An experimental campaign in the tensile mode was carried out at different temperatures and for various glycol proportions in the cooling liquid, for monotonic and cyclic loadings on a neat and a reinforced PPS. The results of these tests allowed to highlight some of the main physical phenomena occurring during these solicitations under tough hydro-thermal conditions. Indeed, the performed tests showed that temperature and liquid cooling aging can affect the mechanical behavior of the material in several ways. The more the cooling liquid contains water, the more the mechanical behavior is affected. It was observed that PPS showed a higher sensitivity to absorption than to chemical aggressiveness of the cooling liquid, explaining this dominant sensitivity. Two kinds of behaviors were noted: an elasto-plastic type under the glass transition temperature and a visco-pseudo-plastic one above it. It was also shown that viscosity is the leading phenomenon above the glass transition temperature for the PPS and could also be important under this temperature, mostly under cyclic conditions and when the stress rate is low. Finally, it was observed that soliciting this composite at high temperatures is decreasing the advantages of the presence of fibers. A new phenomenological model was then built to take into account these experimental observations. This new model allowed the prediction of the evolution of mechanical properties as a function of the loading environment, with a reduced number of parameters compared to precedent studies. It was also shown that the presented approach enables the description and the prediction of the mechanical response with very good accuracy (2% of average error at worst), over a wide range of hydrothermal conditions. A temperature-humidity equivalence principle was underlined for the PPS, allowing the consideration of aging effects within the proposed model. Then, a limit of improvement of the reachable accuracy was determinate for all models using this set of data by the application of an artificial intelligence-based model allowing a comparison between artificial intelligence-based models and phenomenological based ones.

Keywords: aging, analytical modeling, mechanical testing, polymer matrix composites, sequential model, thermomechanical

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Authors: P. Dubcek, B. Pivac, J. Dasovic, V. Janicki, S. Bernstorff

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When grown only to nanometric sizes, metallic particles (e.g. Ag, Au and Cu) exhibit specific optical properties caused by the presence of plasmon band. The plasmon band represents collective oscillation of the conduction electrons, and causes a narrow band absorption of light in the visible range. When the nanoparticles are embedded in a dielectric, they also cause modifications of dielectrics optical properties. This can be fine-tuned by tuning the particle size. We investigated Cu nanoparticle growth with and without surrounding dielectric (SiO2 capping layer). The morphology and crystallinity were investigated by GISAXS and GIWAXS, respectively. Samples were produced by high vacuum thermal evaporation of Cu onto monocrystalline silicon substrate held at room temperature, 100°C or 180°C. One series was in situ capped by 10nm SiO2 layer. Additionally, samples were annealed at different temperatures up to 550°C, also in high vacuum. The room temperature deposited samples annealed at lower temperatures exhibit continuous film structure: strong oscillations in the GISAXS intensity are present especially in the capped samples. At higher temperatures enhanced surface dewetting and Cu nanoparticles (nanoislands) formation partially destroy the flatness of the interface. Therefore the particle type of scattering is enhanced, while the film fringes are depleted. However, capping layer hinders particle formation, and continuous film structure is preserved up to higher annealing temperatures (visible as strong and persistent fringes in GISAXS), compared to the non- capped samples. According to GISAXS, lateral particle sizes are reduced at higher temperatures, while particle height is increasing. This is ascribed to close packing of the formed particles at lower temperatures, and GISAXS deduced sizes are partially the result of the particle agglomerate dimensions. Lateral maxima in GISAXS are an indication of good positional correlation, and the particle to particle distance is increased as the particles grow with temperature elevation. This coordination is much stronger in the capped and lower temperature deposited samples. The dewetting is much more vigorous in the non-capped sample, and since nanoparticles are formed in a range of sizes, correlation is receding both with deposition and annealing temperature. Surface topology was checked by atomic force microscopy (AFM). Capped sample's surfaces were smoother and lateral size of the surface features were larger compared to the non-capped samples. Altogether, AFM results suggest somewhat larger particles and wider size distribution, and this can be attributed to the difference in probe size. Finally, the plasmonic effect was monitored by UV-Vis reflectance spectroscopy, and relative weak plasmonic effect could be explained by uncomplete dewetting or partial interconnection of the formed particles.

Keywords: coper, GISAXS, nanoparticles, plasmonics

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Authors: Lynn Brunet

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In 2019 the author published a book-length study examining Jung’s Red Book. This study consisted of a close reading of each of the chapters in Liber Novus, focussing on the fantasies themselves and Jung’s accompanying paintings. It found that the plots, settings, characters and symbolism in each of these fantasies are not entirely original but remarkably similar to those found in some of the higher degrees of Continental Freemasonry. Jung was the grandson of his namesake, C.G. Jung (1794–1864), who was a Freemason and one-time Grand Master of the Swiss Masonic Lodge. The study found that the majority of Jung’s fantasies are very similar to those of the Ancient and Accepted Scottish Rite, practiced in Switzerland during the time of Jung’s childhood. It argues that the fantasies appear to be memories of a series of terrifying initiatory ordeals conducted using spurious versions of the Masonic rites. Spurious Freemasonry is a term that Masons use for the ‘irregular’ or illegitimate use of the rituals and are not sanctioned by the Order. Since the 1980s there have been multiple reports of ritual trauma amongst a wide variety of organizations, cults and religious groups that psychologists, counsellors, social workers, and forensic scientists have confirmed. The abusive use of Masonic rites features frequently in these reports. This initial study allows a reading of The Red Book that makes sense of the obscure references, bizarre scenarios and intense emotional trauma described by Jung throughout Liber Novus. It suggests that Jung appears to have undergone a cruel initiatory process as a child. The author is currently examining the extra material found in Jung’s Black Books and the results are confirming the original discoveries and demonstrating a number of aspects not covered in the first publication. These include the complex layering of ancient gods and belief systems in answer to Jung’s question, ‘In which underworld am I?’ It demonstrates that the majority of these ancient systems and their gods are discussed in a handbook for the Scottish Rite, Morals and Dogma by Albert Pike, but that the way they are presented by Philemon and his soul is intended to confuse him rather than clarify their purpose. This new study also examines Jung’s soul’s question ‘I am not a human being. What am I then?’ While further themes that emerge from the Black Books include his struggle with vanity and whether he should continue creating his ‘holy book’; and a comparison between Jung’s ‘mystery plays’ and examples from the Theatre of the Absurd. Overall, it demonstrates that Jung’s experience, while inexplicable in his own time, is now known to be the secret and abusive practice of initiation of the young found in a range of cults and religious groups in many first world countries. This paper will present a brief outline of the original study and then examine the themes that have emerged from the extra material found in the Black Books.

Keywords: C. G. Jung, the red book, the black books, masonic themes, trauma and dissociation, initiation rites, secret societies

Procedia PDF Downloads 132

Authors: Juan C. Pérez-Mesa, Emilio Galdeano-Gómez, Jerónimo De Burgos-Jiménez, José F. Bienvenido-Bárcena, José F. Jiménez-Guerrero

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Environmental cost and transport congestion on roads resulting from product distribution in Europe have to lead to the creation of various programs and studies seeking to reduce these negative impacts. In this regard, apart from other institutions, the European Commission (EC) has designed plans in recent years promoting a more sustainable transportation model in an attempt to ultimately shift traffic from the road to the sea by using intermodality to achieve a model rebalancing. This issue proves especially relevant in supply chains from peripheral areas of the continent, where the supply of certain agrifood products is high. In such cases, the most difficult challenge is managing perishable goods. This study focuses on new approaches that strengthen the modal shift, as well as the reduction of externalities. This problem is analyzed by attempting to promote intermodal system (truck and short sea shipping) for transport, taking as point of reference highly perishable products (vegetables) exported from southeast Spain, which is the leading supplier to Europe. Methodologically, this paper seeks to contribute to the literature by proposing a different and complementary approach to establish a comparison between intermodal and the “only road” alternative. For this purpose, the multicriteria decision is utilized in a p-median model (P-M) adapted to the transport of perishables and to a means of shipping selection problem, which must consider different variables: transit cost, including externalities, time, and frequency (including agile response time). This scheme avoids bias in decision-making processes. By observing the results, it can be seen that the influence of the externalities as drivers of the modal shift is reduced when transit time is introduced as a decision variable. These findings confirm that the general strategies, those of the EC, based on environmental benefits lose their capacity for implementation when they are applied to complex circumstances. In general, the different estimations reveal that, in the case of perishables, intermodality would be a secondary and viable option only for very specific destinations (for example, Hamburg and nearby locations, the area of influence of London, Paris, and the Netherlands). Based on this framework, the general outlook on this subject should be modified. Perhaps the government should promote specific business strategies based on new trends in the supply chain, not only on the reduction of externalities, and find new approaches that strengthen the modal shift. A possible option is to redefine ports, conceptualizing them as digitalized redistribution and coordination centers and not only as areas of cargo exchange.

Keywords: environmental externalities, intermodal transport, perishable food, transit time

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Authors: Panagiotis Lemonakis, Nikolaos Moisiadis, Andromachi Gkoutzini, George Kaliabetsos, Nikos Eliou

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The proper surface water drainage not only affects vehicle movement dynamics but also increases the likelihood of an accident due to the fact that inadequate drainage is associated with potential hydroplaning and splash and spray driving conditions. Nine solutions have been proposed to address hydroplaning in sections with inadequate drainage, e.g., augmented superelevation and longitudinal rates, reduction of runoff length, and skew superelevation. The latter has been extensively implemented in highways recently, enhancing the safety level in the applied road segments in regards to the effective drainage of the rainwater. However, the concept of the skew superelevation has raised concerns regarding the driver’s comfort when traveling over skew superelevation sections, particularly at high speeds. These concerns alleviated through the concept of the round-up skew superelevation, which reduces both the lateral and the vertical acceleration imposed to the drivers and hence, improves comfort and traffic safety. Various research studies aimed at investigating driving comfort by evaluating the lateral and vertical accelerations sustained by the road users and vehicles. These studies focused on the influence of the skew superelevation to passenger cars, buses and trucks, and the drivers themselves, traveling at a certain range of speeds either below or above the design speed. The outcome of these investigations which based on the use of simulations, revealed that the imposed accelerations did not exceed the statutory thresholds even when the travelling speed was significantly greater than the design speed. Nevertheless, the effect of the skew superelevation to other vehicle types for instance, motorcycles, has not been investigated so far. The present research study aims to bridge this gap by investigating the impact of skew superelevation on the motorcycle rider’s comfort. Power two-wheeler riders are susceptible to any changes on the pavement surface and therefore a comparison between the traditional superelevation practice and the skew superelevation concept is of paramount importance. The methodology based on the utilization of sophisticated software in order to design the model of the road for several values of the longitudinal slope. Based on the values of the slopes and the use of a mathematical equation, the accelerations imposed on the wheel of the motorcycle were calculated. Due to the fact that the final aim of the study is the influence of the skew superelevation to the rider, it was deemed necessary to convey the calculated accelerations from the wheel to the rider. That was accomplished by implementing the quarter car suspension model adjusted to the features of two-wheeler vehicles. Finally, the accelerations derived from this process evaluated according to specific thresholds originated from the International Organization for Standardization, which correspond to certain levels of comfort. The most important conclusion drawn is that the comfort of the riders is not dependent on the form of road gradient to a great extent due to the fact that the vertical acceleration imposed to the riders took similar values regardless of the value of the longitudinal slope.

Keywords: acceleration, comfort, motorcycle, safety, skew superelevation

Procedia PDF Downloads 151

Authors: Jan Masak, Eva Kvasnickova, Vladimir Scholtz, Olga Matatkova, Marketa Valkova, Alena Cejkova

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Microbial colonization of medical instruments, catheters, implants, etc. is a serious problem in the spread of nosocomial infections. Biofilms exhibit enormous resistance to environment. The resistance of biofilm populations to antibiotic or biocides often increases by two to three orders of magnitude in comparison with suspension populations. Subjects of interests are substances or physical processes that primarily cause the destruction of biofilm, while the released cells can be killed by existing antibiotics. In addition, agents that do not have a strong lethal effect do not cause such a significant selection pressure to further enhance resistance. Non-thermal plasma (NTP) is defined as neutral, ionized gas composed of particles (photons, electrons, positive and negative ions, free radicals and excited or non-excited molecules) which are in permanent interaction. In this work, the effect of NTP generated by the cometary corona with a metallic grid on the formation and stability of biofilm and metabolic activity of cells in biofilm was studied. NTP was applied on biofilm populations of Staphylococcus epidermidis DBM 3179, Pseudomonas aeruginosa DBM 3081, DBM 3777, ATCC 15442 and ATCC 10145, Escherichia coli DBM 3125 and Candida albicans DBM 2164 grown on solid media on Petri dishes and on the titanium alloy (Ti6Al4V) surface used for the production joint replacements. Erythromycin (for S. epidermidis), polymyxin B (for E. coli and P. aeruginosa), amphotericin B (for C. albicans) and ceftazidime (for P. aeruginosa) were used to study the combined effect of NTP and antibiotics. Biofilms were quantified by crystal violet assay. Metabolic activity of the cells in biofilm was measured using MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) colorimetric test based on the reduction of MTT into formazan by the dehydrogenase system of living cells. Fluorescence microscopy was applied to visualize the biofilm on the surface of the titanium alloy; SYTO 13 was used as a fluorescence probe to stain cells in the biofilm. It has been shown that biofilm populations of all studied microorganisms are very sensitive to the type of used NTP. The inhibition zone of biofilm recorded after 60 minutes exposure to NTP exceeded 20 cm², except P. aeruginosa DBM 3777 and ATCC 10145, where it was about 9 cm². Also metabolic activity of cells in biofilm differed for individual microbial strains. High sensitivity to NTP was observed in S. epidermidis, in which the metabolic activity of biofilm decreased after 30 minutes of NTP exposure to 15% and after 60 minutes to 1%. Conversely, the metabolic activity of cells of C. albicans decreased to 53% after 30 minutes of NTP exposure. Nevertheless, this result can be considered very good. Suitable combinations of exposure time of NTP and the concentration of antibiotic achieved in most cases a remarkable synergic effect on the reduction of the metabolic activity of the cells of the biofilm. For example, in the case of P. aeruginosa DBM 3777, a combination of 30 minutes of NTP with 1 mg/l of ceftazidime resulted in a decrease metabolic activity below 4%.

Keywords: anti-biofilm activity, antibiotic, non-thermal plasma, opportunistic pathogens

Procedia PDF Downloads 183