Search results for: fixed effect model
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 28794

Search results for: fixed effect model

2004 Challenges of Outreach Team Leaders in Managing Ward Based Primary Health Care Outreach Teams in National Health Insurance Pilot Districts in Kwazulu-Natal

Authors: E. M. Mhlongo, E. Lutge

Abstract:

In 2010, South Africa’s National Department of Health (NDoH) launched national primary health care (PHC) initiative to strengthen health promotion, disease prevention, and early disease detection. The strategy, called Re-engineering Primary Health Care (rPHC), aims to support a preventive and health-promoting community-based PHC model by using community-based outreach teams (known in South Africa as Ward-based Primary Health Care Outreach teams or WBPHCOTs). These teams provide health education, promote healthy behaviors, assess community health needs, manage minor health problems, and support linkages to health services and health facilities. Ward based primary health care outreach teams are supervised by a professional nurse who is the outreach team leader. In South Africa, the WBPHCOTs have been established, registered, and are reporting their activities in the District Health Information System (DHIS). This study explored and described the challenges faced by outreach team leaders in supporting and supervising the WBPHCOTs. Qualitative data were obtained through interviews conducted with the outreach team leaders at a sub-district level. Thematic analysis of data was done. Findings revealed some challenges faced by team leaders in day to day execution of their duties. Issues such as staff shortages, inadequate resources to carry out health promotion activities, and lack of co-operation from team members may undermine the capacity of team leaders to support and supervise the WBPHCOTs. Many community members are under the impression that the outreach team is responsible for bringing the clinic to the community while the outreach teams do not carry any medication/treatment with them when doing home visits. The study further highlights issues around the challenges of WBPHCOTs at a household level. In conclusion, the WBPHCOTs are an important component of National Health Insurance (NHI), and in order for NHI to be optimally implemented, the issues raised in this research should be addressed with some urgency.

Keywords: community health worker, national health insurance, primary health care, ward-based primary health care outreach teams

Procedia PDF Downloads 127
2003 Towards Learning Query Expansion

Authors: Ahlem Bouziri, Chiraz Latiri, Eric Gaussier

Abstract:

The steady growth in the size of textual document collections is a key progress-driver for modern information retrieval techniques whose effectiveness and efficiency are constantly challenged. Given a user query, the number of retrieved documents can be overwhelmingly large, hampering their efficient exploitation by the user. In addition, retaining only relevant documents in a query answer is of paramount importance for an effective meeting of the user needs. In this situation, the query expansion technique offers an interesting solution for obtaining a complete answer while preserving the quality of retained documents. This mainly relies on an accurate choice of the added terms to an initial query. Interestingly enough, query expansion takes advantage of large text volumes by extracting statistical information about index terms co-occurrences and using it to make user queries better fit the real information needs. In this respect, a promising track consists in the application of data mining methods to extract dependencies between terms, namely a generic basis of association rules between terms. The key feature of our approach is a better trade off between the size of the mining result and the conveyed knowledge. Thus, face to the huge number of derived association rules and in order to select the optimal combination of query terms from the generic basis, we propose to model the problem as a classification problem and solve it using a supervised learning algorithm such as SVM or k-means. For this purpose, we first generate a training set using a genetic algorithm based approach that explores the association rules space in order to find an optimal set of expansion terms, improving the MAP of the search results. The experiments were performed on SDA 95 collection, a data collection for information retrieval. It was found that the results were better in both terms of MAP and NDCG. The main observation is that the hybridization of text mining techniques and query expansion in an intelligent way allows us to incorporate the good features of all of them. As this is a preliminary attempt in this direction, there is a large scope for enhancing the proposed method.

Keywords: supervised leaning, classification, query expansion, association rules

Procedia PDF Downloads 311
2002 Real-Time Data Stream Partitioning over a Sliding Window in Real-Time Spatial Big Data

Authors: Sana Hamdi, Emna Bouazizi, Sami Faiz

Abstract:

In recent years, real-time spatial applications, like location-aware services and traffic monitoring, have become more and more important. Such applications result dynamic environments where data as well as queries are continuously moving. As a result, there is a tremendous amount of real-time spatial data generated every day. The growth of the data volume seems to outspeed the advance of our computing infrastructure. For instance, in real-time spatial Big Data, users expect to receive the results of each query within a short time period without holding in account the load of the system. But with a huge amount of real-time spatial data generated, the system performance degrades rapidly especially in overload situations. To solve this problem, we propose the use of data partitioning as an optimization technique. Traditional horizontal and vertical partitioning can increase the performance of the system and simplify data management. But they remain insufficient for real-time spatial Big data; they can’t deal with real-time and stream queries efficiently. Thus, in this paper, we propose a novel data partitioning approach for real-time spatial Big data named VPA-RTSBD (Vertical Partitioning Approach for Real-Time Spatial Big data). This contribution is an implementation of the Matching algorithm for traditional vertical partitioning. We find, firstly, the optimal attribute sequence by the use of Matching algorithm. Then, we propose a new cost model used for database partitioning, for keeping the data amount of each partition more balanced limit and for providing a parallel execution guarantees for the most frequent queries. VPA-RTSBD aims to obtain a real-time partitioning scheme and deals with stream data. It improves the performance of query execution by maximizing the degree of parallel execution. This affects QoS (Quality Of Service) improvement in real-time spatial Big Data especially with a huge volume of stream data. The performance of our contribution is evaluated via simulation experiments. The results show that the proposed algorithm is both efficient and scalable, and that it outperforms comparable algorithms.

Keywords: real-time spatial big data, quality of service, vertical partitioning, horizontal partitioning, matching algorithm, hamming distance, stream query

Procedia PDF Downloads 146
2001 Factors Associated with Recurrence and Long-Term Survival in Younger and Postmenopausal Women with Breast Cancer

Authors: Sopit Tubtimhin, Chaliya Wamaloon, Anchalee Supattagorn

Abstract:

Background and Significance: Breast cancer is the most frequently diagnosed and leading cause of cancer death among women. This study aims to determine factors potentially predicting recurrence and long-term survival after the first recurrence in surgically treated patients between postmenopausal and younger women. Methods and Analysis: A retrospective cohort study was performed on 498 Thai women with invasive breast cancer, who had undergone mastectomy and been followed-up at Ubon Ratchathani Cancer Hospital, Thailand. We collected based on a systematic chart audit from medical records and pathology reports between January 1, 2002, and December 31, 2011. The last follow-up time point for surviving patients was December 31, 2016. A Cox regression model was used to calculate hazard ratios of recurrence and death. Findings: The median age was 49 (SD ± 9.66) at the time of diagnosis, 47% was post-menopausal women ( ≥ 51years and not experienced any menstrual flow for a minimum of 12 months), and 53 % was younger women ( ˂ 51 years and have menstrual period). Median time from the diagnosis to the last follow-up or death was 10.81 [95% CI = 9.53-12.07] years in younger cases and 8.20 [95% CI = 6.57-9.82] years in postmenopausal cases. The recurrence-free survival (RFS) for younger estimates at 1, 5 and 10 years of 95.0 %, 64.0% and 58.93% respectively, appeared slightly better than the 92.7%, 58.1% and 53.1% for postmenopausal women [HRadj = 1.25, 95% CI = 0.95-1.64]. Regarding overall survival (OS) for younger at 1, 5 and 10 years were 97.7%, 72.7 % and 52.7% respectively, for postmenopausal patients, OS at 1, 5 and 10 years were 95.7%, 70.0% and 44.5 respectively, there were no significant differences in survival [HRadj = 1.23, 95% CI = 0.94 -1.64]. Multivariate analysis identified five risk factors for negatively impacting on survival were triple negative [HR= 2.76, 95% CI = 1.47-5.19], Her2-enriched [HR = 2.59, 95% CI = 1.37-4.91], luminal B [HR = 2.29, 95 % CI=1.35-3.89], not free margin [HR = 1.98, 95%CI=1.00-3.96] and patients who received only adjuvant chemotherapy [HR= 3.75, 95% CI = 2.00-7.04]. Statistically significant risks of overall cancer recurrence were Her2-enriched [HR = 5.20, 95% CI = 2.75-9.80], triple negative [HR = 3.87, 95% CI = 1.98-7.59], luminal B [HR= 2.59, 95% CI = 1.48-4.54,] and patients who received only adjuvant chemotherapy [HR= 2.59, 95% CI = 1.48-5.66]. Discussion and Implications: Outcomes from this studies have shown that postmenopausal women have been associated with increased risk of recurrence and mortality. As the results, it provides useful information for planning the screening and treatment of early-stage breast cancer in the future.

Keywords: breast cancer, menopause status, recurrence-free survival, overall survival

Procedia PDF Downloads 152
2000 Sexual Health Experiences of Older Men: Health Care Professionals' Perspectives

Authors: Andriana E. Tran, Anna Chur-Hansen

Abstract:

Sexual health is an important aspect of overall wellbeing. This study aimed to explore the sexual health experiences of men aged 50 years and over from the perspective of health care professional participants who were specializing in sexual health care and who consulted with older men. A total of ten interviews were conducted. Eleven themes were identified regarding men’s experiences with sexual health care as reported by participants. 1) Biologically focused: older male clients focus largely on the biological aspect of their sexual health without consideration of other factors which might affect their functioning. 2) Psychological concerns: there is an interaction between mental and sexual health but older male clients do not necessarily see this. 3) Medicalization of sexual functioning: advances in medicine that aid with erectile difficulties which consequently mean that older men tend to favor a medical solution to their sexual concerns. 4) Masculine identity: sexual health concerns are linked to older male clients’ sense of masculinity. 5) Penile functionality: most concerns that older male clients have center on their penile functionality. 6) Relationships: many male clients seek sexual help as they believe it improves relationships. Conversely, having supportive partners may mean older male clients focus less on the physicality of sex. 7) Grief and loss: men experience grief and loss – the loss of their sexual functioning, grief from loss of a long-term partner, and loss of intimacy and privacy when moving from independent living to residential care. 8) Social stigma: older male clients experience stigma around aging sexuality and sex in general. 9) Help-seeking behavior: older male clients will usually seek mechanistic solution for biological sexual concerns, such as medication used for penile dysfunction. 10) Dismissed by health care professionals: many older male clients seek specialist sexual health care without the knowledge of their doctors as they feel dismissed due to lack of expertise, lack of time, and the doctor’s personal attitudes and characteristics. Finally, 11) Lack of resources: there is a distinct lack of resources and training to understand sexuality for healthy older men. These findings may inform future research, professional training, public health campaigns and policies for sexual health in older men.

Keywords: ageing, biopsychosocial model, men's health, sexual health

Procedia PDF Downloads 158
1999 Krill-Herd Step-Up Approach Based Energy Efficiency Enhancement Opportunities in the Offshore Mixed Refrigerant Natural Gas Liquefaction Process

Authors: Kinza Qadeer, Muhammad Abdul Qyyum, Moonyong Lee

Abstract:

Natural gas has become an attractive energy source in comparison with other fossil fuels because of its lower CO₂ and other air pollutant emissions. Therefore, compared to the demand for coal and oil, that for natural gas is increasing rapidly world-wide. The transportation of natural gas over long distances as a liquid (LNG) preferable for several reasons, including economic, technical, political, and safety factors. However, LNG production is an energy-intensive process due to the tremendous amount of power requirements for compression of refrigerants, which provide sufficient cold energy to liquefy natural gas. Therefore, one of the major issues in the LNG industry is to improve the energy efficiency of existing LNG processes through a cost-effective approach that is 'optimization'. In this context, a bio-inspired Krill-herd (KH) step-up approach was examined to enhance the energy efficiency of a single mixed refrigerant (SMR) natural gas liquefaction (LNG) process, which is considered as a most promising candidate for offshore LNG production (FPSO). The optimal design of a natural gas liquefaction processes involves multivariable non-linear thermodynamic interactions, which lead to exergy destruction and contribute to process irreversibility. As key decision variables, the optimal values of mixed refrigerant flow rates and process operating pressures were determined based on the herding behavior of krill individuals corresponding to the minimum energy consumption for LNG production. To perform the rigorous process analysis, the SMR process was simulated in Aspen Hysys® software and the resulting model was connected with the Krill-herd approach coded in MATLAB. The optimal operating conditions found by the proposed approach significantly reduced the overall energy consumption of the SMR process by ≤ 22.5% and also improved the coefficient of performance in comparison with the base case. The proposed approach was also compared with other well-proven optimization algorithms, such as genetic and particle swarm optimization algorithms, and was found to exhibit a superior performance over these existing approaches.

Keywords: energy efficiency, Krill-herd, LNG, optimization, single mixed refrigerant

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1998 Effects of Cold Treatments on Methylation Profiles and Reproduction Mode of Diploid and Tetraploid Plants of Ranunculus kuepferi (Ranunculaceae)

Authors: E. Syngelaki, C. C. F. Schinkel, S. Klatt, E. Hörandl

Abstract:

Environmental influence can alter the conditions for plant development and can trigger changes in epigenetic variation. Thus, the exposure to abiotic environmental stress can lead to different DNA methylation profiles and may have evolutionary consequences for adaptation. Epigenetic control mechanisms may further influence mode of reproduction. The alpine species R. kuepferi has diploid and tetraploid cytotypes, that are mostly sexual and facultative apomicts, respectively. Hence, it is a suitable model system for studying the correlations of mode of reproduction, ploidy, and environmental stress. Diploid and tetraploid individuals were placed in two climate chambers and treated with low (+7°C day/+2°C night, -1°C cold shocks for three nights per week) and warm (control) temperatures (+15°C day/+10°C night). Subsequently, methylation sensitive-Amplified Fragment-Length Polymorphism (AFPL) markers were used to screen genome-wide methylation alterations triggered by stress treatments. The dataset was analyzed for four groups regarding treatment (cold/warm) and ploidy level (diploid/tetraploid), and also separately for full methylated, hemi-methylated and unmethylated sites. Patterns of epigenetic variation suggested that diploids differed significantly in their profiles from tetraploids independent from treatment, while treatments did not differ significantly within cytotypes. Furthermore, diploids are more differentiated than the tetraploids in overall methylation profiles of both treatments. This observation is in accordance with the increased frequency of apomictic seed formation in diploids and maintenance of facultative apomixis in tetraploids during the experiment. Global analysis of molecular variance showed higher epigenetic variation within groups than among them, while locus-by-locus analysis of molecular variance showed a high number (54.7%) of significantly differentiated un-methylated loci. To summarise, epigenetic variation seems to depend on ploidy level, and in diploids may be correlated to changes in mode of reproduction. However, further studies are needed to elucidate the mechanism and possible functional significance of these correlations.

Keywords: apomixis, cold stress, DNA methylation, Ranunculus kuepferi

Procedia PDF Downloads 147
1997 Phenotype Prediction of DNA Sequence Data: A Machine and Statistical Learning Approach

Authors: Mpho Mokoatle, Darlington Mapiye, James Mashiyane, Stephanie Muller, Gciniwe Dlamini

Abstract:

Great advances in high-throughput sequencing technologies have resulted in availability of huge amounts of sequencing data in public and private repositories, enabling a holistic understanding of complex biological phenomena. Sequence data are used for a wide range of applications such as gene annotations, expression studies, personalized treatment and precision medicine. However, this rapid growth in sequence data poses a great challenge which calls for novel data processing and analytic methods, as well as huge computing resources. In this work, a machine and statistical learning approach for DNA sequence classification based on $k$-mer representation of sequence data is proposed. The approach is tested using whole genome sequences of Mycobacterium tuberculosis (MTB) isolates to (i) reduce the size of genomic sequence data, (ii) identify an optimum size of k-mers and utilize it to build classification models, (iii) predict the phenotype from whole genome sequence data of a given bacterial isolate, and (iv) demonstrate computing challenges associated with the analysis of whole genome sequence data in producing interpretable and explainable insights. The classification models were trained on 104 whole genome sequences of MTB isoloates. Cluster analysis showed that k-mers maybe used to discriminate phenotypes and the discrimination becomes more concise as the size of k-mers increase. The best performing classification model had a k-mer size of 10 (longest k-mer) an accuracy, recall, precision, specificity, and Matthews Correlation coeffient of 72.0%, 80.5%, 80.5%, 63.6%, and 0.4 respectively. This study provides a comprehensive approach for resampling whole genome sequencing data, objectively selecting a k-mer size, and performing classification for phenotype prediction. The analysis also highlights the importance of increasing the k-mer size to produce more biological explainable results, which brings to the fore the interplay that exists amongst accuracy, computing resources and explainability of classification results. However, the analysis provides a new way to elucidate genetic information from genomic data, and identify phenotype relationships which are important especially in explaining complex biological mechanisms.

Keywords: AWD-LSTM, bootstrapping, k-mers, next generation sequencing

Procedia PDF Downloads 152
1996 Phenotype Prediction of DNA Sequence Data: A Machine and Statistical Learning Approach

Authors: Darlington Mapiye, Mpho Mokoatle, James Mashiyane, Stephanie Muller, Gciniwe Dlamini

Abstract:

Great advances in high-throughput sequencing technologies have resulted in availability of huge amounts of sequencing data in public and private repositories, enabling a holistic understanding of complex biological phenomena. Sequence data are used for a wide range of applications such as gene annotations, expression studies, personalized treatment and precision medicine. However, this rapid growth in sequence data poses a great challenge which calls for novel data processing and analytic methods, as well as huge computing resources. In this work, a machine and statistical learning approach for DNA sequence classification based on k-mer representation of sequence data is proposed. The approach is tested using whole genome sequences of Mycobacterium tuberculosis (MTB) isolates to (i) reduce the size of genomic sequence data, (ii) identify an optimum size of k-mers and utilize it to build classification models, (iii) predict the phenotype from whole genome sequence data of a given bacterial isolate, and (iv) demonstrate computing challenges associated with the analysis of whole genome sequence data in producing interpretable and explainable insights. The classification models were trained on 104 whole genome sequences of MTB isoloates. Cluster analysis showed that k-mers maybe used to discriminate phenotypes and the discrimination becomes more concise as the size of k-mers increase. The best performing classification model had a k-mer size of 10 (longest k-mer) an accuracy, recall, precision, specificity, and Matthews Correlation coeffient of 72.0 %, 80.5 %, 80.5 %, 63.6 %, and 0.4 respectively. This study provides a comprehensive approach for resampling whole genome sequencing data, objectively selecting a k-mer size, and performing classification for phenotype prediction. The analysis also highlights the importance of increasing the k-mer size to produce more biological explainable results, which brings to the fore the interplay that exists amongst accuracy, computing resources and explainability of classification results. However, the analysis provides a new way to elucidate genetic information from genomic data, and identify phenotype relationships which are important especially in explaining complex biological mechanisms

Keywords: AWD-LSTM, bootstrapping, k-mers, next generation sequencing

Procedia PDF Downloads 139
1995 An Investigative Study into Good Governance in the Non-Profit Sector in South Africa: A Systems Approach Perspective

Authors: Frederick M. Dumisani Xaba, Nokuthula G. Khanyile

Abstract:

There is a growing demand for greater accountability, transparency and ethical conduct based on sound governance principles in the developing world. Funders, donors and sponsors are increasingly demanding more transparency, better value for money and adherence to good governance standards. The drive towards improved governance measures is largely influenced by the need to ‘plug the leaks’, deal with malfeasance, engender greater levels of accountability and good governance and to ultimately attract further funding or investment. This is the case with the Non-Profit Organizations (NPOs) in South Africa in general, and in the province of KwaZulu-Natal in particular. The paper draws from the good governance theory, stakeholder theory and systems thinking to critically examine the requirements for good governance for the NPO sector from a theoretical and legislative point and to systematically looks at the contours of governance currently among the NPOs. The paper did this through the rigorous examination of the vignettes of cases of governance among selected NPOs based in KwaZulu-Natal. The study used qualitative and quantitative research methodologies through document analysis, literature review, semi-structured interviews, focus groups and statistical analysis from the various primary and secondary sources. It found some good cases of good governance but also found frightening levels of poor governance. There was an exponential growth of NPOs registered during the period under review, equally so there was an increase in cases of non-compliance to good governance practices. NPOs operate in an increasingly complex environment. There is contestation for influence and access to resources. Stakeholder management is poorly conceptualized and executed. Recognizing that the NPO sector operates in an environment characterized by complexity, constant changes, unpredictability, contestation, diversity and divergent views of different stakeholders, there is a need to apply legislative and systems thinking approaches to strengthen governance to withstand this turbulence through a capacity development model that recognizes these contextual and environmental challenges.

Keywords: good governance, non-profit organizations, stakeholder theory, systems theory

Procedia PDF Downloads 112
1994 Study of the Transport of ²²⁶Ra Colloidal in Mining Context Using a Multi-Disciplinary Approach

Authors: Marine Reymond, Michael Descostes, Marie Muguet, Clemence Besancon, Martine Leermakers, Catherine Beaucaire, Sophie Billon, Patricia Patrier

Abstract:

²²⁶Ra is one of the radionuclides resulting from the disintegration of ²³⁸U. Due to its half-life (1600 y) and its high specific activity (3.7 x 1010 Bq/g), ²²⁶Ra is found at the ultra-trace level in the natural environment (usually below 1 Bq/L, i.e. 10-13 mol/L). Because of its decay in ²²²Rn, a radioactive gas with a shorter half-life (3.8 days) which is difficult to control and dangerous for humans when inhaled, ²²⁶Ra is subject to a dedicated monitoring in surface waters especially in the context of uranium mining. In natural waters, radionuclides occur in dissolved, colloidal or particular forms. Due to the size of colloids, generally ranging between 1 nm and 1 µm and their high specific surface areas, the colloidal fraction could be involved in the transport of trace elements, including radionuclides in the environment. The colloidal fraction is not always easy to determine and few existing studies focus on ²²⁶Ra. In the present study, a complete multidisciplinary approach is proposed to assess the colloidal transport of ²²⁶Ra. It includes water sampling by conventional filtration (0.2µm) and the innovative Diffusive Gradient in Thin Films technique to measure the dissolved fraction (<10nm), from which the colloidal fraction could be estimated. Suspended matter in these waters were also sampled and characterized mineralogically by X-Ray Diffraction, infrared spectroscopy and scanning electron microscopy. All of these data, which were acquired on a rehabilitated former uranium mine, allowed to build a geochemical model using the geochemical calculation code PhreeqC to describe, as accurately as possible, the colloidal transport of ²²⁶Ra. Colloidal transport of ²²⁶Ra was found, for some of the sampling points, to account for up to 95% of the total ²²⁶Ra measured in water. Mineralogical characterization and associated geochemical modelling highlight the role of barite, a barium sulfate mineral well known to trap ²²⁶Ra into its structure. Barite was shown to be responsible for the colloidal ²²⁶Ra fraction despite the presence of kaolinite and ferrihydrite, which are also known to retain ²²⁶Ra by sorption.

Keywords: colloids, mining context, radium, transport

Procedia PDF Downloads 140
1993 Three Issues for Integrating Artificial Intelligence into Legal Reasoning

Authors: Fausto Morais

Abstract:

Artificial intelligence has been widely used in law. Programs are able to classify suits, to identify decision-making patterns, to predict outcomes, and to formalize legal arguments as well. In Brazil, the artificial intelligence victor has been classifying cases to supreme court’s standards. When those programs act doing those tasks, they simulate some kind of legal decision and legal arguments, raising doubts about how artificial intelligence can be integrated into legal reasoning. Taking this into account, the following three issues are identified; the problem of hypernormatization, the argument of legal anthropocentrism, and the artificial legal principles. Hypernormatization can be seen in the Brazilian legal context in the Supreme Court’s usage of the Victor program. This program generated efficiency and consistency. On the other hand, there is a feasible risk of over standardizing factual and normative legal features. Then legal clerks and programmers should work together to develop an adequate way to model legal language into computational code. If this is possible, intelligent programs may enact legal decisions in easy cases automatically cases, and, in this picture, the legal anthropocentrism argument takes place. Such an argument argues that just humans beings should enact legal decisions. This is so because human beings have a conscience, free will, and self unity. In spite of that, it is possible to argue against the anthropocentrism argument and to show how intelligent programs may work overcoming human beings' problems like misleading cognition, emotions, and lack of memory. In this way, intelligent machines could be able to pass legal decisions automatically by classification, as Victor in Brazil does, because they are binding by legal patterns and should not deviate from them. Notwithstanding, artificial intelligent programs can be helpful beyond easy cases. In hard cases, they are able to identify legal standards and legal arguments by using machine learning. For that, a dataset of legal decisions regarding a particular matter must be available, which is a reality in Brazilian Judiciary. Doing such procedure, artificial intelligent programs can support a human decision in hard cases, providing legal standards and arguments based on empirical evidence. Those legal features claim an argumentative weight in legal reasoning and should serve as references for judges when they must decide to maintain or overcome a legal standard.

Keywords: artificial intelligence, artificial legal principles, hypernormatization, legal anthropocentrism argument, legal reasoning

Procedia PDF Downloads 130
1992 Topographic Characteristics Derived from UAV Images to Detect Ephemeral Gully Channels

Authors: Recep Gundogan, Turgay Dindaroglu, Hikmet Gunal, Mustafa Ulukavak, Ron Bingner

Abstract:

A majority of total soil losses in agricultural areas could be attributed to ephemeral gullies caused by heavy rains in conventionally tilled fields; however, ephemeral gully erosion is often ignored in conventional soil erosion assessments. Ephemeral gullies are often easily filled from normal soil tillage operations, which makes capturing the existing ephemeral gullies in croplands difficult. This study was carried out to determine topographic features, including slope and aspect composite topographic index (CTI) and initiation points of gully channels, using images obtained from unmanned aerial vehicle (UAV) images. The study area was located in Topcu stream watershed in the eastern Mediterranean Region, where intense rainfall events occur over very short time periods. The slope varied between 0.7 and 99.5%, and the average slope was 24.7%. The UAV (multi-propeller hexacopter) was used as the carrier platform, and images were obtained with the RGB camera mounted on the UAV. The digital terrain models (DTM) of Topçu stream micro catchment produced using UAV images and manual field Global Positioning System (GPS) measurements were compared to assess the accuracy of UAV based measurements. Eighty-one gully channels were detected in the study area. The mean slope and CTI values in the micro-catchment obtained from DTMs generated using UAV images were 19.2% and 3.64, respectively, and both slope and CTI values were lower than those obtained using GPS measurements. The total length and volume of the gully channels were 868.2 m and 5.52 m³, respectively. Topographic characteristics and information on ephemeral gully channels (location of initial point, volume, and length) were estimated with high accuracy using the UAV images. The results reveal that UAV-based measuring techniques can be used in lieu of existing GPS and total station techniques by using images obtained with high-resolution UAVs.

Keywords: aspect, compound topographic index, digital terrain model, initial gully point, slope, unmanned aerial vehicle

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1991 Matrix-Based Linear Analysis of Switched Reluctance Generator with Optimum Pole Angles Determination

Authors: Walid A. M. Ghoneim, Hamdy A. Ashour, Asmaa E. Abdo

Abstract:

In this paper, linear analysis of a Switched Reluctance Generator (SRG) model is applied on the most common configurations (4/2, 6/4 and 8/6) for both conventional short-pitched and fully-pitched designs, in order to determine the optimum stator/rotor pole angles at which the maximum output voltage is generated per unit excitation current. This study is focused on SRG analysis and design as a proposed solution for renewable energy applications, such as wind energy conversion systems. The world’s potential to develop the renewable energy technologies through dedicated scientific researches was the motive behind this study due to its positive impact on economy and environment. In addition, the problem of rare earth metals (Permanent magnet) caused by mining limitations, banned export by top producers and environment restrictions leads to the unavailability of materials used for rotating machines manufacturing. This challenge gave authors the opportunity to study, analyze and determine the optimum design of the SRG that has the benefit to be free from permanent magnets, rotor windings, with flexible control system and compatible with any application that requires variable-speed operation. In addition, SRG has been proved to be very efficient and reliable in both low-speed or high-speed applications. Linear analysis was performed using MATLAB simulations based on the (Modified generalized matrix approach) of Switched Reluctance Machine (SRM). About 90 different pole angles combinations and excitation patterns were simulated through this study, and the optimum output results for each case were recorded and presented in detail. This procedure has been proved to be applicable for any SRG configuration, dimension and excitation pattern. The delivered results of this study provide evidence for using the 4-phase 8/6 fully pitched SRG as the main optimum configuration for the same machine dimensions at the same angular speed.

Keywords: generalized matrix approach, linear analysis, renewable applications, switched reluctance generator

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1990 TiO₂ Nanoparticles Induce DNA Damage and Expression of Biomarker of Oxidative Stress on Human Spermatozoa

Authors: Elena Maria Scalisi

Abstract:

The increasing production and the use of TiO₂ nanoparticles (NPs) have inevitably led to their release into the environment, thereby posing a threat to organisms and also for human. Human exposure to TiO₂-NPs may occur during both manufacturing and use. TiO₂-NPs are common in consumer products for dermal application, toothpaste, food colorants, and nutritional supplements, then oral exposure may occur during use of such products. Into the body, TiO₂-NPs thanks to their small size (<100 nm), can, through testicular blood barrier inducing effect on testis and then on male reproductive health. The nanoscale size of TiO₂ increase the surface-to-volume ratio making them more reactive in a cell, then TiO₂ NPs increase their ability to produce reactive oxygen species (ROS). In male germ cells, ROS may have important implications in maintaining the normal functions of mature spermatozoa at physiological levels, moreover, in spermatozoa they are important signaling molecules for their hyperactivation and acrosome reaction. Nevertheless, an excess of ROS by external inputs such as NPs can increased the oxidative stress (OS), which results in damage DNA and apoptosis. The aim of our study has been investigate the impact of TiO₂ NPs on human spermatozoa, evaluating DNA damage and the expression of proteins involved in cell stress. According WHO guidelines 2021, we have exposed human spermatozoa in vitro to TiO₂ NP at concentrations 50 ppm, 100 ppm, 250 ppm, and 500 ppm for 1 hour (at 37°C and CO₂ at 5%). DNA damage was evaluated by Sperm Chromatin Dispersion Test (SCD) and TUNEL assay; moreover, we have evaluated the expression of biomarkers of oxidative stress like Heat Shock Protein 70 (HSP70) and Metallothioneins (MTs). Also, sperm parameters as motility viability have been evaluated. Our results not report a significant reduction in motility of spermatozoa at the end of the exposure. On the contrary, the progressive motility was increased at the highest concentration (500 ppm) and was statistically significant compared to control (p <0.05). Also, viability was not changed by exposure to TiO₂-NPs (p <0.05). However, increased DNA damage was observed at all concentrations, and the TUNEL assay highlighted the presence of single strand breaks in the DNA. The spermatozoa responded to the presence of TiO₂-NPs with the expression of Hsp70, which have a protective function because they allow the maintenance of cellular homeostasis in stressful/ lethal conditions. A positivity for MTs was observed mainly for the concentration of 4 mg/L. Although the biological and physiological function of the metallothionein (MTs) in the male genital organs is unclear, our results highlighted that the MTs expressed by spermatozoa maintain their biological role of detoxification from metals. Our results can give additional information to the data in the literature on the toxicity of TiO₂-NPs and reproduction.

Keywords: human spermatozoa, DNA damage, TiO₂-NPs, biomarkers

Procedia PDF Downloads 135
1989 Factors Impacting Geostatistical Modeling Accuracy and Modeling Strategy of Fluvial Facies Models

Authors: Benbiao Song, Yan Gao, Zhuo Liu

Abstract:

Geostatistical modeling is the key technic for reservoir characterization, the quality of geological models will influence the prediction of reservoir performance greatly, but few studies have been done to quantify the factors impacting geostatistical reservoir modeling accuracy. In this study, 16 fluvial prototype models have been established to represent different geological complexity, 6 cases range from 16 to 361 wells were defined to reproduce all those 16 prototype models by different methodologies including SIS, object-based and MPFS algorithms accompany with different constraint parameters. Modeling accuracy ratio was defined to quantify the influence of each factor, and ten realizations were averaged to represent each accuracy ratio under the same modeling condition and parameters association. Totally 5760 simulations were done to quantify the relative contribution of each factor to the simulation accuracy, and the results can be used as strategy guide for facies modeling in the similar condition. It is founded that data density, geological trend and geological complexity have great impact on modeling accuracy. Modeling accuracy may up to 90% when channel sand width reaches up to 1.5 times of well space under whatever condition by SIS and MPFS methods. When well density is low, the contribution of geological trend may increase the modeling accuracy from 40% to 70%, while the use of proper variogram may have very limited contribution for SIS method. It can be implied that when well data are dense enough to cover simple geobodies, few efforts were needed to construct an acceptable model, when geobodies are complex with insufficient data group, it is better to construct a set of robust geological trend than rely on a reliable variogram function. For object-based method, the modeling accuracy does not increase obviously as SIS method by the increase of data density, but kept rational appearance when data density is low. MPFS methods have the similar trend with SIS method, but the use of proper geological trend accompany with rational variogram may have better modeling accuracy than MPFS method. It implies that the geological modeling strategy for a real reservoir case needs to be optimized by evaluation of dataset, geological complexity, geological constraint information and the modeling objective.

Keywords: fluvial facies, geostatistics, geological trend, modeling strategy, modeling accuracy, variogram

Procedia PDF Downloads 247
1988 Impacts of Climate Change and Natural Gas Operations on the Hydrology of Northeastern BC, Canada: Quantifying the Water Budget for Coles Lake

Authors: Sina Abadzadesahraei, Stephen Déry, John Rex

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Climate research has repeatedly identified strong associations between anthropogenic emissions of ‘greenhouses gases’ and observed increases of global mean surface air temperature over the past century. Studies have also demonstrated that the degree of warming varies regionally. Canada is not exempt from this situation, and evidence is mounting that climate change is beginning to cause diverse impacts in both environmental and socio-economic spheres of interest. For example, northeastern British Columbia (BC), whose climate is controlled by a combination of maritime, continental and arctic influences, is warming at a greater rate than the remainder of the province. There are indications that these changing conditions are already leading to shifting patterns in the region’s hydrological cycle, and thus its available water resources. Coincident with these changes, northeastern BC is undergoing rapid development for oil and gas extraction: This depends largely on subsurface hydraulic fracturing (‘fracking’), which uses enormous amounts of freshwater. While this industrial activity has made substantial contributions to regional and provincial economies, it is important to ensure that sufficient and sustainable water supplies are available for all those dependent on the resource, including ecological systems. In this turn demands a comprehensive understanding of how water in all its forms interacts with landscapes, the atmosphere, and of the potential impacts of changing climatic conditions on these processes. The aim of this study is therefore to characterize and quantify all components of the water budget in the small watershed of Coles Lake (141.8 km², 100 km north of Fort Nelson, BC), through a combination of field observations and numerical modelling. Baseline information will aid the assessment of the sustainability of current and future plans for freshwater extraction by the oil and gas industry, and will help to maintain the precarious balance between economic and environmental well-being. This project is a perfect example of interdisciplinary research, in that it not only examines the hydrology of the region but also investigates how natural gas operations and growth can affect water resources. Therefore, a fruitful collaboration between academia, government and industry has been established to fulfill the objectives of this research in a meaningful manner. This project aims to provide numerous benefits to BC communities. Further, the outcome and detailed information of this research can be a huge asset to researchers examining the effect of climate change on water resources worldwide.

Keywords: northeastern British Columbia, water resources, climate change, oil and gas extraction

Procedia PDF Downloads 249
1987 E-Commerce Product Return Management Effects on Consumer Experience and Satisfaction: A Fast-Fashion Perspective

Authors: Nora Alomar, Bianca Alexandra Stefa, Saleh Bazi

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This research uncovers the determinants that drive millennial consumers to adhere to product return of fast-fashion products purchases via e-commerce and what effects it has on consumer experience and satisfaction. Online consumption has skyrocketed, with e-commerce being the only, most reliable, and safe method of shopping during and post Covid-19. It has been noted customers are demanding a wide variety of product characteristics and a generous optimal return policy. The authors have selected to examine millennial consumers as they are digital natives and have an affinity for researching, reading product reviews, and shopping online, with a great spending power due to a higher disposable income in comparison to other generations. A multi-study approach is adopted, where study one (interviews, sample of 20 respondents) investigates the factors that drive product return, and study two (PLS-SEM, sample of 250 respondents) looks into the relationships of product return management against behavioral outcomes by having the generated factors (from study one) as moderators. Five themes are generated from study one (return policies, product characteristics, delivery lead time, seasonality, product trial & overspending). The authors identify that two out of the five factors (seasonality, product trial & overspending) have not been highlighted by the literature. The paper examines 11 hypotheses, where 10 are supported. Findings highlight the quality of the product return management influences the overall millennial customer experience and satisfaction. Findings also indicate that product return management was identified to have a significant negative effect on customer experience. Additionally, seasonality has a significant but negative moderation, which means increasing seasonality decreases the relationship between product return management and customer experience and satisfaction. Results highlight that return policies have a significant negative influence on the relationship between returning a product and customer experience and satisfaction. Moreover, product characteristics are also identified to have a significant negative influence on the relationship between returning a product and customer experience and satisfaction. This study further examines the influence of the factors on direct e-commerce websites and third-party e-commerce websites. Findings showcase a strong statistical significance for the increased rate of return of fast-fashion products on third-party websites. This paper aids practitioners in taking strategic decisions related to return management, to improve the quality of logistical services and, in turn, increase profitability.

Keywords: customer experience, customer satisfaction, e-commerce, fast-fashion, product returns

Procedia PDF Downloads 97
1986 Identification of the Most Effective Dosage of Clove Oil Solution as an Alternative for Synthetic Anaesthetics on Zebrafish (Danio rerio)

Authors: D. P. N. De Silva, N. P. P. Liyanage

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Zebrafish (Danio rerio) in the family Cyprinidae, is a tropical freshwater fish widely used as a model organism in scientific research. Use of effective and economical anaesthetic is very important when handling fish. Clove oil (active ingredient: eugenol) was identified as a natural product which is safer and economical compared to synthetic chemicals like methanesulfonate (MS-222). Therefore, the aim of this study was to identify the most effective dosage of clove oil solution as an anaesthetic on mature Zebrafish. Clove oil solution was prepared by mixing pure clove oil with 94% ethanol at a ratio of 1:9 respectively. From that solution, different volumes were selected as (0.4 ml, 0.6 ml and 0.8 ml) and dissolved in one liter of conditioned water (dosages : 0.4 ml/L, 0.6 ml/L and 0.8 ml/L). Water quality parameters (pH, temperature and conductivity) were measured before and after adding clove oil solution. Mature Zebrafish with similar standard length (2.76 ± 0.1 cm) and weight (0.524 ± 0.1 g) were selected for this experiment. Time taken for loss of equilibrium (initiation phase) and complete loss of movements including opercular movement (anaesthetic phase) were measured. To detect the efficacy on anaesthetic recovery, time taken to begin opercular movements (initiation of recovery phase) until swimming (post anaesthetic phase) were observed. The results obtained were analyzed according to the analysis of variance (ANOVA) and Tukeys’ method using SPSS version 17.0 at 95% confidence interval (p<0.5). According to the results, there was no significant difference at the initiation phase of anaesthesia in all three doses though the time taken was varied from 0.14 to 0.41 minutes. Mean value of the time taken to complete the anaesthetic phase at 0.4 ml/L dosage was significantly different with 0.6 ml/L and 0.8 ml/L dosages independently (p=0.01). There was no significant difference among recovery times at all dosages but 0.8 ml/L dosage took longer time compared to 0.6 ml/L dosage. The water quality parameters (pH and temperature) were stable throughout the experiment except conductivity, which increased with the higher dosage. In conclusion, the best dosage need to anaesthetize Zebrafish using clove oil solution was 0.6 ml/L due to its fast initiation of anaesthesia and quick recovery compared to the other two dosages. Therefore clove oil can be used as a good substitute for synthetic anaesthetics because of its efficacy at a lower dosage with higher safety at a low cost.

Keywords: anaesthetics, clove oil, zebrafish, Cyprinidae

Procedia PDF Downloads 699
1985 Coping Strategies Used by Pregnant Women in India to Overcome the Psychological Impact of COVID-19

Authors: Harini Atturu, Divyani Byagari, Bindhu Rani Thumkunta, Sahitya Bammidi, Manasa Badveli

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Introduction: Biological, psychological and social domains influence the outcomes of pregnancy. The COVID19 pandemic had a significant effect on the psychological and social domains of pregnant women all over the world. Everyone has inherent coping mechanisms which ultimately determine the actual impact of such external stimulus on outcomes of pregnancy. This study aims to understand the coping strategies used by pregnant women to overcome the psychological impact of the first wave of the COVID 19 pandemic. Methods: Institutional ethics permission was sought. All pregnant women attending antenatal clinics in the institution during September 2020 were included in the study. Brief-COPE, a self-rated questionnaire, was provided to understand the coping strategies used by them. The Questionnaire consists of 28 questions that fall into 14 themes. These 14 themes were mapped into four domains consisting of Approaching coping (APC) styles, Avoidant Coping (AVC) styles, Humor and Religion. The results were analyzed using univariate and multivariate analysis. Factor analysis was performed to identify themes that are most frequently used. Results: 162 pregnant women were included in the study. The majority of the women were aged between 18 and 30 (90.1%). 60.9% of the respondents were having their first pregnancy and were in the 2nd trimester (59.6%). The majority of them were living in the city (74%), belonged to the middle class (77.6%) and were not working (70.1%). 56 respondents (34.6%) reported that they had contact with suspected or Covid positive patients. Many were worried that their pregnancy might be complicated (43%), their baby may contract COVID (45%) and their family members could get COVID during the hospital visits for antenatal check-ups. 33.6% of women admitted missing their regular antenatal check-ups because of the above concerns. All respondents used various coping strategies to overcome the psychological impact of COVID 19. Out of the 4 coping strategies, participants scored high on Religion with a mean of 5.471.45 followed by Approaching Coping (APC) styles (5.131.25), Humor (4.592.07) and Avoidant Coping (AVC) styles (4.130.88). Religion as a coping strategy scored high for all respondents irrespective of age, parity, trimester, social and employment status. Exploratory Factor analysis revealed two cluster groups that explained 68% of the variance, with Component 1 contributing to 58.9% and component 2 contributing 9.13% of the variance. Humor, Acceptance, Planning, and Religion were the top 4 factors that showed strong loadings. Conclusion: Most of the pregnant women were worried about the negative impact of COVID 19 on the outcomes of their pregnancy. Religion and Approaching coping styles seem to be the predominant coping strategies used by them. Interventionists and policymakers should consider these factors while providing support to such women.

Keywords: coping strategies, pregnancy, COVID-19, brief-COPE

Procedia PDF Downloads 120
1984 Immersive Environment as an Occupant-Centric Tool for Architecture Criticism and Architectural Education

Authors: Golnoush Rostami, Farzam Kharvari

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In recent years, developments in the field of architectural education have resulted in a shift from conventional teaching methods to alternative state-of-the-art approaches in teaching methods and strategies. Criticism in architecture has been a key player both in the profession and education, but it has been mostly offered by renowned individuals. Hence, not only students or other professionals but also critics themselves may not have the option to experience buildings and rely on available 2D materials, such as images and plans, that may not result in a holistic understanding and evaluation of buildings. On the other hand, immersive environments provide students and professionals the opportunity to experience buildings virtually and reflect their evaluation by experiencing rather than judging based on 2D materials. Therefore, the aim of this study is to compare the effect of experiencing buildings in immersive environments and 2D drawings, including images and plans, on architecture criticism and architectural education. As a result, three buildings that have parametric brick facades were studied through 2D materials and in Unreal Engine v. 24 as an immersive environment among 22 architecture students that were selected using convenient sampling and were divided into two equal groups using simple random sampling. This study used mixed methods, including quantitative and qualitative methods; the quantitative section was carried out by a questionnaire, and deep interviews were used for the qualitative section. A questionnaire was developed for measuring three constructs, including privacy regulation based on Altman’s theory, the sufficiency of illuminance levels in the building, and the visual status of the view (visually appealing views based on obstructions that may have been caused by facades). Furthermore, participants had the opportunity to reflect their understanding and evaluation of the buildings in individual interviews. Accordingly, the collected data from the questionnaires were analyzed using independent t-test and descriptive analyses in IBM SPSS Statistics v. 26, and interviews were analyzed using the content analysis method. The results of the interviews showed that the participants who experienced the buildings in the immersive environment were able to have a thorough and more precise evaluation of the buildings in comparison to those who studied them through 2D materials. Moreover, the analyses of the respondents’ questionnaires revealed that there were statistically significant differences between measured constructs among the two groups. The outcome of this study suggests that integrating immersive environments into the profession and architectural education as an effective and efficient tool for architecture criticism is vital since these environments allow users to have a holistic evaluation of buildings for vigorous and sound criticism.

Keywords: immersive environments, architecture criticism, architectural education, occupant-centric evaluation, pre-occupancy evaluation

Procedia PDF Downloads 117
1983 Synthesis and Analytical Characterisation of Polymer-Silica Nanoparticles Composite for the Protection and Preservation of Stone Monuments

Authors: Sayed M. Ahmed, Sawsan S. Darwish, Nagib A. Elmarzugi, Mohammad A. Al-Dosari, Mahmoud A. Adam, Nadia A. Al-Mouallimi

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Historical stone surfaces and architectural heritage may undergo unwanted changes due to the exposure to many physical and chemical deterioration factors, the innovative properties of the nano - materials can have advantageous application in the restoration and conservation of the cultural heritage with relation to the tailoring of new products for protection and consolidation of stone. The current work evaluates the effectiveness of inorganic compatible treatments; based on nanosized particles of silica (SiO2) dispersed in silicon based product, commonly used as a water-repellent/ consolidation for the construction materials affected by different kinds of decay. The nanocomposites obtained by dispersing the silica nanoparticles in polymeric matrices SILRES® BS OH 100 (solventless mixtures of ethyl silicates), in order to obtain a new nanocomposite, with hydrophobic and consolidation properties, to improve the physical and mechanical properties of the stone material. The nanocomposites obtained and pure SILRES® BS OH 100 were applied by brush Experimental stone blocks. The efficacy of the treatments has been evaluated after consolidation and artificial Thermal aging, through capillary water absorption measurements, Ultraviolet-light exposure to evaluate photo-induced and the hydrophobic effects of the treated surface, Scanning electron microscopy (SEM) examination is performed to evaluate penetration depth, re-aggregating effects of the deposited phase and the surface morphology before and after artificialaging. Sterio microscopy investigation is performed to evaluate the resistant to the effects of the erosion, acids and salts. Improving of stone mechanical properties were evaluated by compressive strength tests, colorimetric measurements were used to evaluate the optical appearance. All the results get together with the apparent effect that, silica/polymer nanocomposite is efficient material for the consolidation of artistic and architectural sandstone monuments, completely compatible, enhanced the durability of sandstone toward thermal and UV aging. In addition, the obtained nanocomposite improved the stone mechanical properties and the resistant to the effects of the erosion, acids and salts compared to the samples treated with pure SILRES® BS OH 100 without silica nanoparticles.

Keywords: colorimetric measurements, compressive strength, nanocomposites, porous stone consolidation, silica nanoparticles, sandstone

Procedia PDF Downloads 242
1982 Root Cause Analysis of a Catastrophically Failed Output Pin Bush Coupling of a Raw Material Conveyor Belt

Authors: Kaushal Kishore, Suman Mukhopadhyay, Susovan Das, Manashi Adhikary, Sandip Bhattacharyya

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In integrated steel plants, conveyor belts are widely used for transferring raw materials from one location to another. An output pin bush coupling attached with a conveyor transferring iron ore fines and fluxes failed after two years of service life. This led to an operational delay of approximately 15 hours. This study is focused on failure analysis of the coupling and recommending counter-measures to prevent any such failures in the future. Investigation consisted of careful visual observation, checking of operating parameters, stress calculation and analysis, macro and micro-fractography, material characterizations like chemical and metallurgical analysis and tensile and impact testings. The fracture occurred from an unusually sharp double step. There were multiple corrosion pits near the step that aggravated the situation. Inner contact surface of the coupling revealed differential abrasion that created a macroscopic difference in the height of the component. This pointed towards misalignment of the coupling beyond a threshold limit. In addition to these design and installation issues, material of the coupling did not meet the quality standards. These were made up of grey cast iron having graphite morphology intermediate between random distribution (Type A) and rosette pattern (Type B). This manifested as a marked reduction in impact toughness and tensile strength of the component. These findings corroborated well with the brittle mode of fracture that might have occurred during minor impact loading while loading of conveyor belt with raw materials from height. Simulated study was conducted to examine the effect of corrosion pits on tensile and impact toughness of grey cast iron. It was observed that pitting marginally reduced tensile strength and ductility. However, there was marked (up to 45%) reduction in impact toughness due to pitting. Thus, it became evident that failure of the coupling occurred due to combination of factors like inferior material, misalignment, poor step design and corrosion pitting. Recommendation for life enhancement of coupling included the use of tougher SG 500/7 grade, incorporation of proper fillet radius for the step, correction of alignment and application of corrosion resistant organic coating to prevent pitting.

Keywords: brittle fracture, cast iron, coupling, double step, pitting, simulated impact tests

Procedia PDF Downloads 116
1981 Reduced Tillage and Bio-stimulant Application Can Improve Soil Microbial Enzyme Activity in a Dryland Cropping System

Authors: Flackson Tshuma, James Bennett, Pieter Andreas Swanepoel, Johan Labuschagne, Stephan van der Westhuizen, Francis Rayns

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Amongst other things, tillage and synthetic agrochemicals can be effective methods of seedbed preparation and pest control. Nonetheless, frequent and intensive tillage and excessive application of synthetic agrochemicals, such as herbicides and insecticides, can reduce soil microbial enzyme activity. A decline in soil microbial enzyme activity can negatively affect nutrient cycling and crop productivity. In this study, the effects of four tillage treatments; continuous mouldboard plough; shallow tine-tillage to a depth of about 75 mm; no-tillage; and tillage rotation (involving shallow tine-tillage once every four years in rotation with three years of no-tillage), and two rates of synthetic agrochemicals (standard: with regular application of synthetic agrochemicals; and reduced: fewer synthetic agrochemicals in combination with bio-chemicals/ or bio-stimulants) on soil microbial enzyme activity were investigated between 2018 and 2020 in a typical Mediterranean climate zone in South Africa. Four different bio-stimulants applied contained: Trichoderma asperellum, fulvic acid, silicic acid, and Nereocystis luetkeana extracts, respectively. The study was laid out as a complete randomised block design with four replicated blocks. Each block had 14 plots, and each plot measured 50 m x 6 m. The study aimed to assess the combined impact of tillage practices and reduced rates of synthetic agrochemical application on soil microbial enzyme activity in a dryland cropping system. It was hypothesised that the application of bio-stimulants in combination with minimum soil disturbance will lead to a greater increase in microbial enzyme activity than the effect of applying either in isolation. Six soil cores were randomly and aseptically collected from each plot for microbial enzyme activity analysis from the 0-150 mm layer of a field trial under a dryland crop rotation system in the Swartland region. The activities of four microbial enzymes, β-glucosidase, acid phosphatase, alkaline phosphatase and urease, were assessed. The enzymes are essential for the cycling of glucose, phosphorus, and nitrogen, respectively. Microbial enzyme activity generally increased with a reduction of both tillage intensity and synthetic agrochemical application. The use of the mouldboard plough led to the least (P<0.05) microbial enzyme activity relative to the reduced tillage treatments, whereas the system with bio-stimulants (reduced synthetic agrochemicals) led to the highest (P<0.05) microbial enzyme activity relative to the standard systems. The application of bio-stimulants in combination with reduced tillage, particularly no-tillage, could be beneficial for enzyme activity in a dryland farming system.

Keywords: bio-stimulants, soil microbial enzymes, synthetic agrochemicals, tillage

Procedia PDF Downloads 64
1980 The Metabolism of Built Environment: Energy Flow and Greenhouse Gas Emissions in Nigeria

Authors: Yusuf U. Datti

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It is becoming increasingly clear that the consumption of resources now enjoyed in the developed nations will be impossible to be sustained worldwide. While developing countries still have the advantage of low consumption and a smaller ecological footprint per person, they cannot simply develop in the same way as other western cities have developed in the past. The severe reality of population and consumption inequalities makes it contentious whether studies done in developed countries can be translated and applied to developing countries. Additional to this disparities, there are few or no metabolism of energy studies in Nigeria. Rather more contentious majority of energy metabolism studies have been done only in developed countries. While researches in Nigeria concentrate on other aspects/principles of sustainability such as water supply, sewage disposal, energy supply, energy efficiency, waste disposal, etc., which will not accurately capture the environmental impact of energy flow in Nigeria, this research will set itself apart by examining the flow of energy in Nigeria and the impact that the flow will have on the environment. The aim of the study is to examine and quantify the metabolic flows of energy in Nigeria and its corresponding environmental impact. The study will quantify the level and pattern of energy inflow and the outflow of greenhouse emissions in Nigeria. This study will describe measures to address the impact of existing energy sources and suggest alternative renewable energy sources in Nigeria that will lower the emission of greenhouse gas emissions. This study will investigate the metabolism of energy in Nigeria through a three-part methodology. The first step involved selecting and defining the study area and some variables that would affect the output of the energy (time of the year, stability of the country, income level, literacy rate and population). The second step involves analyzing, categorizing and quantifying the amount of energy generated by the various energy sources in the country. The third step involves analyzing what effect the variables would have on the environment. To ensure a representative sample of the study area, Africa’s most populous country, with economy that is the second biggest and that is among the top largest oil producing countries in the world is selected. This is due to the understanding that countries with large economy and dense populations are ideal places to examine sustainability strategies; hence, the choice of Nigeria for the study. National data will be utilized unless where such data cannot be found, then local data will be employed which will be aggregated to reflect the national situation. The outcome of the study will help policy-makers better target energy conservation and efficiency programs and enables early identification and mitigation of any negative effects in the environment.

Keywords: built environment, energy metabolism, environmental impact, greenhouse gas emissions and sustainability

Procedia PDF Downloads 168
1979 Creating and Questioning Research-Oriented Digital Outputs to Manuscript Metadata: A Case-Based Methodological Investigation

Authors: Diandra Cristache

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The transition of traditional manuscript studies into the digital framework closely affects the methodological premises upon which manuscript descriptions are modeled, created, and questioned for the purpose of research. This paper intends to explore the issue by presenting a methodological investigation into the process of modeling, creating, and questioning manuscript metadata. The investigation is founded on a close observation of the Polonsky Greek Manuscripts Project, a collaboration between the Universities of Cambridge and Heidelberg. More than just providing a realistic ground for methodological exploration, along with a complete metadata set for computational demonstration, the case study also contributes to a broader purpose: outlining general methodological principles for making the most out of manuscript metadata by means of research-oriented digital outputs. The analysis mainly focuses on the scholarly approach to manuscript descriptions, in the specific instance where the act of metadata recording does not have a programmatic research purpose. Close attention is paid to the encounter of 'traditional' practices in manuscript studies with the formal constraints of the digital framework: does the shift in practices (especially from the straight narrative of free writing towards the hierarchical constraints of the TEI encoding model) impact the structure of metadata and its capability to respond specific research questions? It is argued that flexible structure of TEI and traditional approaches to manuscript description lead to a proliferation of markup: does an 'encyclopedic' descriptive approach ensure the epistemological relevance of the digital outputs to metadata? To provide further insight on the computational approach to manuscript metadata, the metadata of the Polonsky project are processed with techniques of distant reading and data networking, thus resulting in a new group of digital outputs (relational graphs, geographic maps). The computational process and the digital outputs are thoroughly illustrated and discussed. Eventually, a retrospective analysis evaluates how the digital outputs respond to the scientific expectations of research, and the other way round, how the requirements of research questions feed back into the creation and enrichment of metadata in an iterative loop.

Keywords: digital manuscript studies, digital outputs to manuscripts metadata, metadata interoperability, methodological issues

Procedia PDF Downloads 127
1978 Multi-Criteria Nautical Ports Capacity and Services Planning

Authors: N. Perko, N. Kavran, M. Bukljas, I. Berbic

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This paper is a result of implemented research on proposed introduced methodology for nautical ports capacity planning by introducing a multi-criteria approach of defined criteria and impacts at the Adriatic Sea. The purpose was analysing the determinants -characteristics of infrastructure and services of nautical ports capacity allocated, especially nowadays due to COVID-19 pandemic, as crucial for the successful operation of nautical ports. Giving the importance of the defined priorities for short-term and long-term planning is essential not only in terms of the development of nautical tourism but also in terms of developing the maritime system, but unfortunately, this is not always carried out. Evaluation of the use of resources should follow from a detailed analysis of all aspects of resources bearing in mind that nautical tourism used resources in a sustainable manner and generate effects in the tourism and maritime sectors. Consequently, the identified multiplier effect of nautical tourism, which should be defined and quantified in detail, should be one of the major competitive products on the Croatian Adriatic and the Mediterranean. Research of nautical tourism is necessary to quantify the effects and required planning system development. In the future, the greatest threat to the long-term sustainable development of nautical tourism can be its further uncontrolled or unlimited and undirected development, especially under pressure markedly higher demand than supply for new moorings in the Mediterranean. Results of this implemented research are applicable to nautical ports management and decision-makers of maritime transport system development. This paper will present implemented research and obtained result-developed methodology for nautical port capacity planning -port capacity planning multi-criteria decision-making. A proposed methodological approach of multi-criteria capacity planning includes four criteria (spatial - transport, cost - infrastructure, ecological and organizational criteria, and additional services). The importance of the criteria and sub-criteria is evaluated and carried out as the basis for sensitivity analysis of the importance of the criteria and sub-criteria. Based on the analysis of the identified and quantified importance of certain criteria and sub-criteria, as well as sensitivity analysis and analysis of changes of the quantified importance, scientific and applicable results will be presented. These obtained results have practical applicability by management of nautical ports in the planning of increasing capacity and further development and for the adaptation of existing nautical ports. Obtained research is applicable and replicable in other seas, and results are especially important and useful in this COVID-19 pandemic challenging maritime development framework.

Keywords: Adriatic Sea, capacity, infrastructures, maritime system, methodology, nautical ports, nautical tourism, service

Procedia PDF Downloads 171
1977 The Markers -mm and dämmo in Amharic: Developmental Approach

Authors: Hayat Omar

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Languages provide speakers with a wide range of linguistic units to organize and deliver information. There are several ways to verbally express the mental representations of events. According to the linguistic tools they have acquired, speakers select the one that brings out the most communicative effect to convey their message. Our study focuses on two markers, -mm and dämmo, in Amharic (Ethiopian Semitic language). Our aim is to examine, from a developmental perspective, how they are used by speakers. We seek to distinguish the communicative and pragmatic functions indicated by means of these markers. To do so, we created a corpus of sixty narrative productions of children from 5-6, 7-8 to 10-12 years old and adult Amharic speakers. The experimental material we used to collect our data is a series of pictures without text 'Frog, Where are you?'. Although -mm and dämmo are each used in specific contexts, they are sometimes analyzed as being interchangeable. The suffix -mm is complex and multifunctional. It marks the end of the negative verbal structure, it is found in the relative structure of the imperfect, it creates new words such as adverbials or pronouns, it also serves to coordinate words, sentences and to mark the link between macro-propositions within a larger textual unit. -mm was analyzed as marker of insistence, topic shift marker, element of concatenation, contrastive focus marker, 'bisyndetic' coordinator. On the other hand, dämmo has limited function and did not attract the attention of many authors. The only approach we could find analyzes it in terms of 'monosyndetic' coordinator. The paralleling of these two elements made it possible to understand their distinctive functions and refine their description. When it comes to marking a referent, the choice of -mm or dämmo is not neutral, depending on whether the tagged argument is newly introduced, maintained, promoted or reintroduced. The presence of these morphemes explains the inter-phrastic link. The information is seized by anaphora or presupposition: -mm goes upstream while dämmo arrows downstream, the latter requires new information. The speaker uses -mm or dämmo according to what he assumes to be known to his interlocutors. The results show that -mm and dämmo, although all the speakers use them both, do not always have the same scope according to the speaker and vary according to the age. dämmo is mainly used to mark a contrastive topic to signal the concomitance of events. It is more commonly used in young children’s narratives (F(3,56) = 3,82, p < .01). Some values of -mm (additive) are acquired very early while others are rather late and increase with age (F(3,56) = 3,2, p < .03). The difficulty is due not only because of its synthetic structure but primarily because it is multi-purpose and requires a memory work. It highlights the constituent on which it operates to clarify how the message should be interpreted.

Keywords: acquisition, cohesion, connection, contrastive topic, contrastive focus, discourse marker, pragmatics

Procedia PDF Downloads 125
1976 Adjustment of the Whole-Body Center of Mass during Trunk-Flexed Walking across Uneven Ground

Authors: Soran Aminiaghdam, Christian Rode, Reinhard Blickhan, Astrid Zech

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Despite considerable studies on the impact of imposed trunk posture on human walking, less is known about such locomotion while negotiating changes in ground level. The aim of this study was to investigate the behavior of the VBCOM in response to a two-fold expected perturbation, namely alterations in body posture and in ground level. To this end, the kinematic data and ground reaction forces of twelve able participants were collected. We analyzed the vertical position of the body center of mass (VBCOM) from the ground determined by the body segmental analysis method relative to the laboratory coordinate system at touchdown and toe-off instants during walking across uneven ground — characterized by perturbation contact (a 10-cm visible drop) and pre- and post-perturbation contacts — in comparison to unperturbed level contact while maintaining three postures (regular erect, ~30° and ~50° of trunk flexion from the vertical). The VBCOM was normalized to the distance between the greater trochanter marker and the lateral malleoli marker at the instant of TD. Moreover, we calculated the backward rotation during step-down as the difference of the maximum of the trunk angle in the pre-perturbation contact and the minimal trunk angle in the perturbation contact. Two-way repeated measures ANOVAs revealed contact-specific effects of posture on the VBCOM at touchdown (F = 5.96, p = 0.00). As indicated by the analysis of simple main effects, during unperturbed level and pre-perturbation contacts, no between-posture differences for the VBCOM at touchdown were found. In the perturbation contact, trunk-flexed gaits showed a significant increase of VBCOM as compared to the pre-perturbation contact. In the post-perturbation contact, the VBCOM demonstrated a significant decrease in all gait postures relative to the preceding corresponding contacts with no between-posture differences. Main effects of posture revealed that the VBCOM at toe-off significantly decreased in trunk-flexed gaits relative to the regular erect gait. For the main effect of contact, the VBCOM at toe-off demonstrated changes across perturbation and post-perturbation contacts as compared to the unperturbed level contact. Furthermore, participants exhibited a backward trunk rotation during step-down possibly to control the angular momentum of their whole body. A more pronounced backward trunk rotation (2- to 3-fold compared with level contacts) in trunk-flexed walking contributed to the observed elevated VBCOM during the step-down which may have facilitated drop negotiation. These results may shed light on the interaction between posture and locomotion in able gait, and specifically on the behavior of the body center of mass during perturbed locomotion.

Keywords: center of mass, perturbation, posture, uneven ground, walking

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1975 Comprehensive Approach to Control Virus Infection and Energy Consumption in An Occupant Classroom

Authors: SeyedKeivan Nateghi, Jan Kaczmarczyk

Abstract:

People nowadays spend most of their time in buildings. Accordingly, maintaining a good quality of indoor air is very important. New universal matters related to the prevalence of Covid-19 also highlight the importance of indoor air conditioning in reducing the risk of virus infection. Cooling and Heating of a house will provide a suitable zone of air temperature for residents. One of the significant factors in energy demand is energy consumption in the building. In general, building divisions compose more than 30% of the world's fundamental energy requirement. As energy demand increased, greenhouse effects emerged that caused global warming. Regardless of the environmental damage to the ecosystem, it can spread infectious diseases such as malaria, cholera, or dengue to many other parts of the world. With the advent of the Covid-19 phenomenon, the previous instructions to reduce energy consumption are no longer responsive because they increase the risk of virus infection among people in the room. Two problems of high energy consumption and coronavirus infection are opposite. A classroom with 30 students and one teacher in Katowice, Poland, considered controlling two objectives simultaneal. The probability of transmission of the disease is calculated from the carbon dioxide concentration of people. Also, in a certain period, the amount of energy consumption is estimated by EnergyPlus. The effect of three parameters of number, angle, and time or schedule of opening windows on the probability of infection transmission and energy consumption of the class were investigated. Parameters were examined widely to determine the best possible condition for simultaneous control of infection spread and energy consumption. The number of opening windows is discrete (0,3), and two other parameters are continuous (0,180) and (8 AM, 2 PM). Preliminary results show that changes in the number, angle, and timing of window openings significantly impact the likelihood of virus transmission and class energy consumption. The greater the number, tilt, and timing of window openings, the less likely the student will transmit the virus. But energy consumption is increasing. When all the windows were closed at all hours of the class, the energy consumption for the first day of January was only 0.2 megajoules. In comparison, the probability of transmitting the virus per person in the classroom is more than 45%. But when all windows were open at maximum angles during class, the chance of transmitting the infection was reduced to 0.35%. But the energy consumption will be 36 megajoules. Therefore, school classrooms need an optimal schedule to control both functions. In this article, we will present a suitable plan for the classroom with natural ventilation through windows to control energy consumption and the possibility of infection transmission at the same time.

Keywords: Covid-19, energy consumption, building, carbon dioxide, energyplus

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