Search results for: series resistance
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5770

Search results for: series resistance

760 Impact of Alternative Fuel Feeding on Fuel Cell Performance and Durability

Authors: S. Rodosik, J. P. Poirot-Crouvezier, Y. Bultel

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With the expansion of the hydrogen economy, Proton Exchange Membrane Fuel Cell (PEMFC) systems are often presented as promising energy converters suitable for transport applications. However, reaching a durability of 5000 h recommended by the U.S. Department of Energy and decreasing system cost are still major hurdles to their development. In order to increase the system efficiency and simplify the system without affecting the fuel cell lifetime, an architecture called alternative fuel feeding has been developed. It consists in a fuel cell stack divided into two parts, alternatively fed, implemented on a 5-kW system for real scale testing. The operation strategy can be considered close to Dead End Anode (DEA) with specific modifications to avoid water and nitrogen accumulation in the cells. The two half-stacks are connected in series to enable each stack to be alternatively fed. Water and nitrogen accumulated can be shifted from one half-stack to the other one according to the alternative feeding frequency. Thanks to the homogenization of water vapor along the stack, water management was improved. The operating conditions obtained at system scale are close to recirculation without the need of a pump or an ejector. In a first part, a performance comparison with the DEA strategy has been performed. At high temperature and low pressure (80°C, 1.2 bar), performance of alternative fuel feeding was higher, and the system efficiency increased. In a second part, in order to highlight the benefits of the architecture on the fuel cell lifetime, two durability tests, lasting up to 1000h, have been conducted. A test on the 5-kW system has been compared to a reference test performed on a test bench with a shorter stack, conducted with well-controlled operating parameters and flow-through hydrogen strategy. The durability test is based upon the Fuel Cell Dynamic Load Cycle (FC-DLC) protocol but adapted to the system limitations: without OCV steps and a maximum current density of 0.4 A/cm². In situ local measurements with a segmented S++® plate performed all along the tests, showed a more homogeneous distribution of the current density with alternative fuel feeding than in flow-through strategy. Tests performed in this work enabled the understanding of this architecture advantages and drawbacks. Alternative fuel feeding architecture appeared to be a promising solution to ensure the humidification function at the anode side with a simplified fuel cell system.

Keywords: automotive conditions, durability, fuel cell system, proton exchange membrane fuel cell, stack architecture

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759 Relationship between Functional Properties and Supramolecular Structure of the Poly(Trimethylene 2,5-Furanoate) Based Multiblock Copolymers with Aliphatic Polyethers or Aliphatic Polyesters

Authors: S. Paszkiewicz, A. Zubkiewicz, A. Szymczyk, D. Pawlikowska, I. Irska, E. Piesowicz, A. Linares, T. A. Ezquerra

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Over the last century, the world has become increasingly dependent on oil as its main source of chemicals and energy. Driven largely by the strong economic growth of India and China, demand for oil is expected to increase significantly in the coming years. This growth in demand, combined with diminishing reserves, will require the development of new, sustainable sources for fuels and bulk chemicals. Biomass is an attractive alternative feedstock, as it is widely available carbon source apart from oil and coal. Nowadays, academic and industrial research in the field of polymer materials is strongly oriented towards bio-based alternatives to petroleum-derived plastics with enhanced properties for advanced applications. In this context, 2,5-furandicarboxylic acid (FDCA), a biomass-based chemical product derived from lignocellulose, is one of the most high-potential biobased building blocks for polymers and the first candidate to replace the petro-derived terephthalic acid. FDCA has been identified as one of the top 12 chemicals in the future, which may be used as a platform chemical for the synthesis of biomass-based polyester. The aim of this study is to synthesize and characterize the multiblock copolymers containing rigid segments of poly(trimethylene 2,5-furanoate) (PTF) and soft segments of poly(tetramethylene oxide) (PTMO) with excellent elastic properties or aliphatic polyesters of polycaprolactone (PCL). Two series of PTF based copolymers, i.e., PTF-block-PTMO-T and PTF-block-PCL-T, with different content of flexible segments were synthesized by means of a two-step melt polycondensation process and characterized by various methods. The rigid segments of PTF, as well as the flexible PTMO/or PCL ones, were randomly distributed along the chain. On the basis of 1H NMR, SAXS and WAXS, DSC an DMTA results, one can conclude that both phases were thermodynamically immiscible and the values of phase transition temperatures varied with the composition of the copolymer. The copolymers containing 25, 35 and 45wt.% of flexible segments (PTMO) exhibited elastomeric property characteristics. Moreover, with respect to the flexible segments content, the temperatures corresponding to 5%, 25%, 50% and 90% mass loss as well as the values of tensile modulus decrease with the increasing content of aliphatic polyether or aliphatic polyester in the composition.

Keywords: furan based polymers, multiblock copolymers, supramolecular structure, functional properties

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758 Recovery of Physical Performance in Postpartum Women: An Effective Physical Education Program

Authors: Julia A. Ermakova

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This study aimed to investigate the efficacy of a physical rehabilitation program for postpartum women. The program was developed with the purpose of restoring physical performance in women during the postpartum period. The research employed a variety of methods, including an analysis of scientific literature, pedagogical testing and experimentation, mathematical processing of study results, and physical performance assessment using a range of tests. The program recommends refraining from abdominal exercises during the first 6-8 months following a cesarean section and avoiding exercises with weights. Instead, a feasible training regimen that gradually increases in intensity several times a week is recommended, along with moderate cardio exercises such as walking, bodyweight training, and a separate workout component that targets posture improvement. Stretching after strength training is also encouraged. The necessary equipment includes comfortable sports attire with a chest support top, mat, push-ups, resistance band, timer, and clock. The motivational aspect of the program is paramount, and the mentee's positive experience with the workout regimen includes feelings of lightness in the body, increased energy, and positive emotions. The gradual reduction of body size and weight loss due to an improved metabolism also serves as positive reinforcement. The mentee's progress can be measured through various means, including an external assessment of her form, body measurements, weight, BMI, and the presence or absence of slouching in everyday life. The findings of this study reveal that the program is effective in restoring physical performance in postpartum women. The mentee achieved weight loss and almost regained her pre-pregnancy shape while her self-esteem improved. Her waist, shoulder, and hip measurements decreased, and she displayed less slouching in her daily life. In conclusion, the developed physical rehabilitation program for postpartum women is an effective means of restoring physical performance. It is crucial to follow the recommended training regimen and equipment to avoid limitations and ensure safety during the postpartum period. The motivational component of the program is also fundamental in encouraging positive reinforcement and improving self-esteem.

Keywords: physical rehabilitation, postpartum, methodology, postpartum recovery, rehabilitation

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757 The Mechanism Study on the Difference between High and Low Voltage Performance of Li3V2(PO4)3

Authors: Enhui Wang, Qingzhu Ou, Yan Tang, Xiaodong Guo

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As one of most popular polyanionic compounds in lithium-ion cathode materials, Li3V2(PO4)3 has always suffered from the low rate capability especially during 3~4.8V, which is considered to be related with the ion diffusion resistance and structural transformation during the Li+ de/intercalation. Here, as the change of cut-off voltages, cycling numbers and current densities, the process of SEI interfacial film’s formation-growing- destruction-repair on the surface of the cathode, the structural transformation during the charge and discharge, the de/intercalation kinetics reflected by the electrochemical impedance and the diffusion coefficient, have been investigated in detail. Current density, cycle numbers and cut-off voltage impacting on interfacial film and structure was studied specifically. Firstly, the matching between electrolyte and material was investigated, it turned out that the batteries with high voltage electrolyte showed the best electrochemical performance and high voltage electrolyte would be the best electrolyte. Secondly, AC impedance technology was used to study the changes of interface impedance and lithium ion diffusion coefficient, the results showed that current density, cycle numbers and cut-off voltage influenced the interfacial film together and the one who changed the interfacial properties most was the key factor. Scanning electron microscopy (SEM) analysis confirmed that the attenuation of discharge specific capacity was associated with the destruction and repair process of the SEI film. Thirdly, the X-ray diffraction was used to study the changes of structure, which was also impacted by current density, cycle numbers and cut-off voltage. The results indicated that the cell volume of Li3V2 (PO4 )3 increased as the current density increased; cycle numbers merely influenced the structure of material; the cell volume decreased first and moved back gradually after two Li-ion had been deintercalated as the charging cut-off voltage increased, and increased as the intercalation number of Li-ion increased during the discharging process. Then, the results which studied the changes of interface impedance and lithium ion diffusion coefficient turned out that the interface impedance and lithium ion diffusion coefficient increased when the cut-off voltage passed the voltage platforms and decreased when the cut-off voltage was between voltage platforms. Finally, three-electrode system was first adopted to test the activation energy of the system, the results indicated that the activation energy of the three-electrode system (22.385 KJ /mol) was much smaller than that of two-electrode system (40.064 KJ /mol).

Keywords: cut-off voltage, de/intercalation kinetics, solid electrolyte interphase film, structural transformation

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756 A Comparative Study of the Impact of Membership in International Climate Change Treaties and the Environmental Kuznets Curve (EKC) in Line with Sustainable Development Theories

Authors: Mojtaba Taheri, Saied Reza Ameli

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In this research, we have calculated the effect of membership in international climate change treaties for 20 developed countries based on the human development index (HDI) and compared this effect with the process of pollutant reduction in the Environmental Kuznets Curve (EKC) theory. For this purpose, the data related to The real GDP per capita with 2010 constant prices is selected from the World Development Indicators (WDI) database. Ecological Footprint (ECOFP) is the amount of biologically productive land needed to meet human needs and absorb carbon dioxide emissions. It is measured in global hectares (gha), and the data retrieved from the Global Ecological Footprint (2021) database will be used, and we will proceed by examining step by step and performing several series of targeted statistical regressions. We will examine the effects of different control variables, including Energy Consumption Structure (ECS) will be counted as the share of fossil fuel consumption in total energy consumption and will be extracted from The United States Energy Information Administration (EIA) (2021) database. Energy Production (EP) refers to the total production of primary energy by all energy-producing enterprises in one country at a specific time. It is a comprehensive indicator that shows the capacity of energy production in the country, and the data for its 2021 version, like the Energy Consumption Structure, is obtained from (EIA). Financial development (FND) is defined as the ratio of private credit to GDP, and to some extent based on the stock market value, also as a ratio to GDP, and is taken from the (WDI) 2021 version. Trade Openness (TRD) is the sum of exports and imports of goods and services measured as a share of GDP, and we use the (WDI) data (2021) version. Urbanization (URB) is defined as the share of the urban population in the total population, and for this data, we used the (WDI) data source (2021) version. The descriptive statistics of all the investigated variables are presented in the results section. Related to the theories of sustainable development, Environmental Kuznets Curve (EKC) is more significant in the period of study. In this research, we use more than fourteen targeted statistical regressions to purify the net effects of each of the approaches and examine the results.

Keywords: climate change, globalization, environmental economics, sustainable development, international climate treaty

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755 Assessment of Mediation of Community-Based Disputes in Selected Barangays of Batangas City

Authors: Daisyree S. Arrieta

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The purpose of this study was to assess the mediation process applied on community-based disputes in the selected barangays of Batangas City, namely: Barangay Sta. Rita Karsada, Barangay Bolbok, and Barangay Alangilan. The researcher initially speculated that the required procedures under Republic Act No. 7160 were not religiously followed and satisfied by the Lupong Tagapamayapa members in most of the barangays in the subject locality and this prompted the researcher to conduct an investigation about this research topic. In this study, the subject barangays and their Lupon members still resorted to mediation processes to amicably settle conflicts among community members. It can also be appreciated among the Lupon Tagapamayapa members that they are aware of the purpose and processes required in the mediation of cases brought before them. However, the manner in which they conduct this mediation processes seems to be dependent on the general characteristics of their respective barangays and of the people situated therein. It also very noticeable that the strategies applied by the Lupon members on these cases depend on the ways and means the parties in dispute may arrive into agreements and conciliations. It is concluded by the researcher that the Lupong Tagapamayapa members in Barangay Sta. Rita Karsada, Barangay Bolbok, and Barangay Alangilan are aware and are applying the objectives and procedures of mediation. Also, the success and failure of the mediation processes applied by the Lupong Tagapamayapa members of the subject barangays on community-based disputes brought before them are generally attributed on the attitude and perspective of the parties in dispute towards the entire process of mediation and not on the capacity or capability of the Lupon members to subject them into amicable settlements. In view of the above, the researcher humbly recommends the following: (1) that the composition of the Lupong Tagapamayapa should include individuals from various sectors of the barangay; (2) that the Lupong Tagapamayapa members should undergo various trainings that may enhance their capability to mediate any type of community-based disputes at the expense of the barangay fund or budget; (3) that the Punong Barangay and the Sangguniang Pambarangay, in their own discretion, should allocate budget that will consistently provide regular honoraria for the Lupong Tagapamayapa members; (4) that the Punong Barangay and the Sangguniang Pambarangay should provide an ideal venue for the hearing of community-based disputes; (5) that the City/ Municipal Governments should allocate necessary financial assistance to the barangays under their jurisdiction in honing eligible Lupong Tagapamayapa members; and (6) that the Punong Barangay and other officials should initiate series of information campaigns for their constituents to be informed on the objectives, advantages, and procedures of mediation.

Keywords: amicable settlement, community-based disputes, dispute resolution, mediation

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754 Modelling Flood Events in Botswana (Palapye) for Protecting Roads Structure against Floods

Authors: Thabo M. Bafitlhile, Adewole Oladele

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Botswana has been affected by floods since long ago and is still experiencing this tragic event. Flooding occurs mostly in the North-West, North-East, and parts of Central district due to heavy rainfalls experienced in these areas. The torrential rains destroyed homes, roads, flooded dams, fields and destroyed livestock and livelihoods. Palapye is one area in the central district that has been experiencing floods ever since 1995 when its greatest flood on record occurred. Heavy storms result in floods and inundation; this has been exacerbated by poor and absence of drainage structures. Since floods are a part of nature, they have existed and will to continue to exist, hence more destruction. Furthermore floods and highway plays major role in erosion and destruction of roads structures. Already today, many culverts, trenches, and other drainage facilities lack the capacity to deal with current frequency for extreme flows. Future changes in the pattern of hydro climatic events will have implications for the design and maintenance costs of roads. Increase in rainfall and severe weather events can affect the demand for emergent responses. Therefore flood forecasting and warning is a prerequisite for successful mitigation of flood damage. In flood prone areas like Palapye, preventive measures should be taken to reduce possible adverse effects of floods on the environment including road structures. Therefore this paper attempts to estimate return periods associated with huge storms of different magnitude from recorded historical rainfall depth using statistical method. The method of annual maxima was used to select data sets for the rainfall analysis. In the statistical method, the Type 1 extreme value (Gumbel), Log Normal, Log Pearson 3 distributions were all applied to the annual maximum series for Palapye area to produce IDF curves. The Kolmogorov-Smirnov test and Chi Squared were used to confirm the appropriateness of fitted distributions for the location and the data do fit the distributions used to predict expected frequencies. This will be a beneficial tool for urgent flood forecasting and water resource administration as proper drainage design will be design based on the estimated flood events and will help to reclaim and protect the road structures from adverse impacts of flood.

Keywords: drainage, estimate, evaluation, floods, flood forecasting

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753 Mechanisms Underlying Comprehension of Visualized Personal Health Information: An Eye Tracking Study

Authors: Da Tao, Mingfu Qin, Wenkai Li, Tieyan Wang

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While the use of electronic personal health portals has gained increasing popularity in the healthcare industry, users usually experience difficulty in comprehending and correctly responding to personal health information, partly due to inappropriate or poor presentation of the information. The way personal health information is visualized may affect how users perceive and assess their personal health information. This study was conducted to examine the effects of information visualization format and visualization mode on the comprehension and perceptions of personal health information among personal health information users with eye tracking techniques. A two-factor within-subjects experimental design was employed, where participants were instructed to complete a series of personal health information comprehension tasks under varied types of visualization mode (i.e., whether the information visualization is static or dynamic) and three visualization formats (i.e., bar graph, instrument-like graph, and text-only format). Data on a set of measures, including comprehension performance, perceptions, and eye movement indicators, were collected during the task completion in the experiment. Repeated measure analysis of variance analyses (RM-ANOVAs) was used for data analysis. The results showed that while the visualization format yielded no effects on comprehension performance, it significantly affected users’ perceptions (such as perceived ease of use and satisfaction). The two graphic visualizations yielded significantly higher favorable scores on subjective evaluations than that of the text format. While visualization mode showed no effects on users’ perception measures, it significantly affected users' comprehension performance in that dynamic visualization significantly reduced users' information search time. Both visualization format and visualization mode had significant main effects on eye movement behaviors, and their interaction effects were also significant. While the bar graph format and text format had similar time to first fixation across dynamic and static visualizations, instrument-like graph format had a larger time to first fixation for dynamic visualization than for static visualization. The two graphic visualization formats yielded shorter total fixation duration compared with the text-only format, indicating their ability to improve information comprehension efficiency. The results suggest that dynamic visualization can improve efficiency in comprehending important health information, and graphic visualization formats were favored more by users. The findings are helpful in the underlying comprehension mechanism of visualized personal health information and provide important implications for optimal design and visualization of personal health information.

Keywords: eye tracking, information comprehension, personal health information, visualization

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752 Tick Infestation and its Implications on Health and Welfare of Cattle under Pastoral System in Nigeria

Authors: Alabi Olufemi, Adeyanju Taiwo, Oloruntoba Oluwasegun, Adeleye Bobola, Alabi Oyekemi

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The pastoral system is a predominant form of cattle production in Nigeria, characterized by extensive grazing on communal lands. However, this system is challenged by various factors, including tick infestation, which significantly affects cattle health and welfare hence this investigation which aims to provide an in-depth understanding of tick infestation in the context of Nigerian pastoral systems, emphasizing its impact on cattle health and welfare. The country harbors a diverse array of tick species that affect cattle. These ticks belong to different genera, including Rhipicephalus, Amblyomma, and Hyalomma, among others. Each species has unique characteristics, life cycles, and host preferences, contributing to the complexity of tick infestation dynamics in pastoral settings. Tick infestation has numerous detrimental effects on cattle health. The direct effects include blood loss, anemia, skin damage due to feeding, and the transmission of pathogens that cause diseases such as anaplasmosis, babesiosis, and theileriosis. Indirectly, tick infestation can lead to reduced productivity, weight loss, and increased susceptibility to other diseases.The welfare of cattle in Nigerian pastoral systems is significantly impacted by tick infestation. Infested cattle often exhibit signs of distress, including restlessness, reduced grazing activity, and altered behavior. Furthermore, the discomfort caused by tick bites can lead to chronic stress, compromising the overall welfare of the animals. Effective tick control is crucial for mitigating the impact of infestation on cattle health and welfare. Strategies such as acaricide application, pasture management, genetic selection for tick resistance cattle, and vaccination against tick-borne diseases are commonly used. Tick infestation presents a significant challenge to cattle production under the pastoral system in Nigeria. It not only impacts cattle health but also compromises their welfare. Addressing the issue of tick infestation requires a multifaceted approach that integrates effective control strategies with sustainable management practices. Further research is needed to develop tailored interventions that account for the unique characteristics of Nigerian pastoral systems, ultimately ensuring the well-being and productivity of cattle in these settings.

Keywords: tick infestation, pastoral system, welfare, cattle

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751 An Empty Canvas is Full

Authors: Joonha Park

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This essay examines the Soviet Artist Pavel Korin’s artistic pursuit towards his life-long project, “Requiem/Passing of the Rus,” framing the funeral of Tikhon, the last great defender of the Russian orthodox Church during the Great purge, as the final moment of “Rus,” which is the identity of the Russian people that built up in the 1000 year of history behind Russian Orthodoxy. Korin’s project remains in the form of a series of 29 man-sized portraits and a monumental blank canvas. Born in a family dedicated to iconography, Korin witnessed the historic drama during Stalin’s terror; therefore, he tried to convey the nation’s mourning for the disappearance of “Rus” and disapproval of the Soviet notion of atheism. Yet, due to Korin’s success as a state artist, many believed that the political pressure led Korin to give up his belief and controversy arose over the fact that Korin left the canvas blank. The empty 40-square-meter canvas, which remains untouched in his studio since 1930, supports this theory to an extent. However, resources such as Korin’s notes, primary accounts from his fellow Soviet Artists, and testimonies from his wife suggested that this assumption is incorrect. Moreover, Korin’s uninterrupted relationship with the church and the religious attributes in his commissioned works were brought up as evidence of Korin’s continued belief. The empty canvas not only represents Korin’s discontentment towards the repression and the hardships that the Orthodox Church experienced, but also depicts the identity that coexisted with the Church in order to bequeath this idea to future generations. The faultless canvas surrounded by the striking 29 portraits is a symbol of the highest spirit, similar to that of the iconography paintings placed in every Russian house that unites the Russian people till this day, therefore one can deduce that the legacy of “Requiem” is still relevant to the Russian people even under freedom of religious expression. Consequently, “Requiem” was on display at the Tretyakov Gallery for the first time in public in 2013 even though Korin started creating this piece in 1925, extolling Korin not only as an artist but also as a historian; by recording the turmoil of the Great Oppression, Korin exhibited the social responsibility universal to artists across time and space. In this essay, the legacy Korin left behind, both to his contemporaries and his posterity is reevaluated through the lens of his works, unfinished as they were.

Keywords: Pavel Korin, Art History, Art, Russia, Soviet Union, Requiem, Russian orthodox church, Treytyakov gallery, contemporary art, socialist realism, Maxim Gorky

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750 Effects of Renin Angiotensin Pathway Inhibition on Efficacy of Anti-PD-1/PD-L1 Treatment in Metastatic Cancer

Authors: Philip Friedlander, John Rutledge, Jason Suh

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Inhibition of programmed death-1 (PD-1) or its ligand PD-L1 confers therapeutic efficacy in a wide range of solid tumor malignancies. Primary or acquired resistance can develop through activation of immunosuppressive immune cells such as tumor-associated macrophages. The renin angiotensin system (RAS) systemically regulates fluid and sodium hemodynamics, but components are expressed on and regulate the activity of immune cells, particularly of myeloid lineage. We hypothesized that inhibition of RAS would improve the efficacy of PD-1/PD-L-1 treatment. A retrospective analysis was performed through a chart review of patients with solid metastatic malignancies treated with a PD-1/PD-L1 inhibitor between 1/2013 and 6/2019 at Valley Hospital, a community hospital in New Jersey, USA. Efficacy was determined by medical oncologist documentation of clinical benefit in visit notes and by the duration of time on immunotherapy treatment. The primary endpoint was the determination of efficacy differences in patients treated with an inhibitor of RAS ( ace inhibitor, ACEi, or angiotensin blocker, ARB) compared to patients not treated with these inhibitors. To control for broader antihypertensive effects, efficacy as a function of treatment with beta blockers was assessed. 173 patients treated with PD-1/PD-L-1 inhibitors were identified of whom 52 were also treated with an ACEi or ARB. Chi-square testing revealed a statistically significant relationship between being on an ACEi or ARB and efficacy to PD-1/PD-L-1 therapy (p=0.001). No statistically significant relationship was seen between patients taking or not taking beta blocker antihypertensives (p= 0.33). Kaplan-Meier analysis showed statistically significant improvement in the duration of therapy favoring patients concomitantly treated with ACEi or ARB compared to patients not exposed to antihypertensives and to those treated with beta blockers. Logistic regression analysis revealed that age, gender, and cancer type did not have significant effects on the odds of experiencing clinical benefit (p=0.74, p=0.75, and p=0.81, respectively). We conclude that retrospective analysis of the treatment of patients with solid metastatic tumors with anti-PD-1/PD-L1 in a community setting demonstrates greater clinical benefit in the context of concomitant ACEi or ARB inhibition, irrespective of gender or age. This data supports the development of prospective assessment through randomized clinical trials.

Keywords: angiotensin, cancer, immunotherapy, PD-1, efficacy

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749 Modeling and Optimizing of Sinker Electric Discharge Machine Process Parameters on AISI 4140 Alloy Steel by Central Composite Rotatable Design Method

Authors: J. Satya Eswari, J. Sekhar Babub, Meena Murmu, Govardhan Bhat

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Electrical Discharge Machining (EDM) is an unconventional manufacturing process based on removal of material from a part by means of a series of repeated electrical sparks created by electric pulse generators at short intervals between a electrode tool and the part to be machined emmersed in dielectric fluid. In this paper, a study will be performed on the influence of the factors of peak current, pulse on time, interval time and power supply voltage. The output responses measured were material removal rate (MRR) and surface roughness. Finally, the parameters were optimized for maximum MRR with the desired surface roughness. RSM involves establishing mathematical relations between the design variables and the resulting responses and optimizing the process conditions. RSM is not free from problems when it is applied to multi-factor and multi-response situations. Design of experiments (DOE) technique to select the optimum machining conditions for machining AISI 4140 using EDM. The purpose of this paper is to determine the optimal factors of the electro-discharge machining (EDM) process investigate feasibility of design of experiment techniques. The work pieces used were rectangular plates of AISI 4140 grade steel alloy. The study of optimized settings of key machining factors like pulse on time, gap voltage, flushing pressure, input current and duty cycle on the material removal, surface roughness is been carried out using central composite design. The objective is to maximize the Material removal rate (MRR). Central composite design data is used to develop second order polynomial models with interaction terms. The insignificant coefficients’ are eliminated with these models by using student t test and F test for the goodness of fit. CCD is first used to establish the determine the optimal factors of the electro-discharge machining (EDM) for maximizing the MRR. The responses are further treated through a objective function to establish the same set of key machining factors to satisfy the optimization problem of the electro-discharge machining (EDM) process. The results demonstrate the better performance of CCD data based RSM for optimizing the electro-discharge machining (EDM) process.

Keywords: electric discharge machining (EDM), modeling, optimization, CCRD

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748 Building up Regional Innovation Systems (RIS) for Development: The Case Study of the State of Mexico, México

Authors: Jose Luis Solleiro, Rosario Castanon, Laura Elena Martinez

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The State of Mexico is an administrative entity of Mexico, and it is one of the most important territories due to its great economic and social impact for the whole country, especially since it contributes with more than eight of the national Gross Domestic Product (GDP). The State of Mexico has a population of over seventeen million people and host very important business and productive industries such as Automotive, Chemicals, Pharmaceutical, and Agri-food. In 2017, the State Development Plan (Plan Estatal de Desarrollo in Spanish) which is a policy document that rules State's economic actions and integrates the bases for sectoral and regional programs to achieve regional development), raised innovation as a key aspect to boost competitiveness and productivity of the State of Mexico. Therefore, in line with this proposal, in 2018 the Mexican Council for Science and Technology (COMECYT for its acronym in Spanish), an institution in charge of promoting public science and technology policies in the State of Mexico, took actions towards building up the State´s Innovation System. Hence, the main objective of this paper is to review and analyze the process to create RIS in the State of Mexico. We focus on the key elements of the process, the diverse actors that were involved in it, the activities that were carried out and the identification of the challenges, findings, successes, and failures of the intended exercise. The methodology used to analyze the structure of the Innovation System of the State of Mexico is based on two elements: the case study and the research-action approach. The main objective of the paper, the case study was based on semi-structured interviews with key actors who have participated in the process of launching the RIS of the State of Mexico. Additionally, we analyzed the information reports and other documents that were elaborated during the process of shaping the State's innovation system. Finally, the results obtained in the process were also examined. The relevance of this investigation fundamentally rests in two elements: 1) keeping documental record of the process of building a RIS in Mexico; and 2) carrying out the analysis of this case study recognizing the importance of knowledge extraction and dissemination, so that lessons on this matter may be useful for similar experiences in the future. We conclude that in Mexico, documentation and analysis efforts related to the formation of RIS and interaction processes between innovation ecosystem actors are scarce, so documents like are of great importance, especially since it generates a series of findings and recommendations for the building of RIS.

Keywords: regional innovation systems, innovation, development, competitiveness

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747 Developing Cultural Competence as Part of Nursing Studies: Language, Customs and Health Issues

Authors: Mohammad Khatib, Salam Hadid

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Introduction: Developing nurses' cultural competence begins in their basic training and requires them to participate in an array of activities which raise their awareness and stimulate their interest, desire and curiosity about different cultures, by creating opportunities for intercultural meetings promoting the concept of 'culture' and its components, including recognition of cultural diversity and the legitimacy of the other. Importantly, professionals need to acquire specific cultural knowledge and thorough understanding of the values, norms, customs, beliefs and symbols of different cultures. Similarly, they need to be given opportunities to practice the verbal and non-verbal communication skills of other cultures according to their cultural codes. Such a system is being implemented as part of nursing studies at Zefat Academic College in two study frameworks; firstly, a course integrating nursing theory and practice in multicultural nursing; secondly, a course in learning the languages spoken in Israel focusing on medical and nursing terminology. Methods: Students participating in the 'Transcultural Nursing' course come from a variety of backgrounds: Jews, or Arabs, religious, or secular; Muslim, Christian, new immigrants, Ethiopians or from other cultural affiliations. They are required to present and discuss cultural practices that affect health. In addition, as part of the language course, students learn and teach their friends 5 spoken languages (Arabic, Russian, Amharian, Yidish, and Sign language) focusing on therapeutic interaction and communication using the vocabulary and concepts necessary for the therapeutic encounter. An evaluation of the process and the results was done using a structured questionnaire which includes series of questions relating to the contributions of the courses to their cultural knowledge, awareness and skills. 155 students completed the questionnaire. Results: A preliminary assessment of this educational system points an increase in cultural awareness and knowledge among the students as well as in their willingness to recognize the other's difference. A positive atmosphere of multiculturalism is reflected in students' mutual interest and respect was created. Students showed a deep understanding of cultural issues relating to health and care (consanguinity and genetics, food customs; cultural events, reincarnation, traditional treatments etc.). Most of the students were willing to recommend the courses to others and suggest some changes relating learning methods (more simulations, role playing and activities).

Keywords: cultural competence, nursing education, culture, language

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746 From the Perspective of a Veterinarian: The Future of Plant Raw Materials Used in the Feeding of Farm Animals

Authors: Ertuğrul Yılmaz

Abstract:

One of the most important occupational groups in the food chain from farm to fork is a veterinary medicine. This occupational group, which has important duties in the prevention of many zoonotic diseases and in public health, takes place in many critical control points from soil to our kitchen. It has important duties from mycotoxins transmitted from the soil to slaughterhouses or milk processing facilities. Starting from the soil, which constitutes 70% of mycotoxin contamination, up to the TMR made from raw materials obtained from the soil, there are all critical control points from feeding to slaughterhouses and milk production enterprises. We can take the precaution of mycotoxins such as Aflatoxin B1, Ochratoxin, Zearalenone, and Fumonisin, which we encounter on farms while in the field. It has been reported that aflatoxin B1 is a casenerogen and passes into milk in studies. It is likely that many mycotoxins pose significant threats to public health and will turn out to be even more dangerous over time. Even raw material storage and TMR preparation are very important for public health. The danger of fumonisin accumulating in the liver will be understood over time. Zoonotic diseases are also explained with examples. In this study, how important veterinarians are in terms of public health is explained with examples. In the two-year mycotoxin screenings, fumonisin mycotoxin was found to be very high in corn and corn by-products, and it was determined that it accumulated in the liver for a long time and remained cornic in animals. It has been determined that mycotoxins are present in all livestock feeds, poultry feeds, and raw materials, not alone, but in double-triple form. Starting from the end, mycotoxin scans should be carried out from feed to raw materials and from raw materials to soil. In this way, we prevent the transmission of mycotoxins to animals and from animals to humans. Liver protectors such as toxin binders, beta-glucan, mannan oligosaccharides, activated carbon, prebiotics, and silymarin were used in certain proportions in the total mixed ratio, and positive results were obtained. Humidity and temperature controls of raw material silos were made at certain intervals. Necropsy was performed on animals that died as a result of mycotoxicosis, and macroscopic photographs were taken of the organs. We have determined that the mycotoxin screening in experimental animals and the feeds made without detecting the presence and amount of bacterial factors affect the results of the project to be made. For this, a series of precautionary plans have been created, starting from the production processes.

Keywords: mycotoxins, feed safety, processes, public health

Procedia PDF Downloads 82
745 Into the Dreamweaver’s World of the Mandaya and the Tboli: From Folklore to the Woven Fabric

Authors: Genevieve Jorolan Quintero

Abstract:

In Mindanao, the southern island of the Philippines, two provinces, Davao Oriental and Tboli of South Cotabato, respectively, are homes to indigenous communities known for their dream weavers. Davao Oriental is home to the Mandaya, while Lake Sebu is home to the Tboli. The dream weavers are mostly women who have continued the tradition of weaving, a spiritual practice of handicraft embodying the beliefs of the community. It is believed that a weaver is guided by the Tagamaling, or the nature spirit in Mandaya mythology, and Fu Dalu, or the spirit of the abaca among the Tboli. In the dream, the Tagamaling or Fu Dalu reveals to the weaver the design or the pattern of the dagmay as the abaca woven cloth is called among the Mandaya and the tnalak among the Tboli. The weaver then undertakes the production of this nature-spirit-inspired fabric based on her memory of the dream. This interaction between the spirit world and the human world inspired the theme of the short story with the title Loom of Dreams, published in 2015 by Kritika Kultura, an international peer-reviewed journal of language and literary/cultural studies of the Ateneo de Manila University in the Philippines. In Lake Sebu, a collection of the legendary tnalak with various designs is preserved by the cultural advocate and tnalak collector Reden S. Ulo. About a hundred tnalak designs are housed in a mini museum. The paper discusses how the dagmay and the tnalak of the two Philippine indigenous communities, the Mandaya and the Tboli, embody their folklore and cultural heritage. The specific objectives are: 1. To describe the role of the dreamweavers among the Mandaya and Tboli communities in the Philippines; 2. To analyse how folklore influences the designs on the woven fabric, the dagmay, and the tnalak, and 3. To discuss how dream-weaving helps preserve culture legacy. Ethnography was used in the conduct of this research. Specifically, the following data collection methods were done: 1. a series of visits to the Mandaya and Tboli communities; 2. face-to-face interviews with the respondents from the communities, and 3. the recording of the interviews with the knowledge-bearers and material culture keepers from both communities, the narratives of which were used as a basis for the data analysis. The influence of folklore in the culture and the arts of the indigenous communities is significantly evident in the designs of the dagmay and the tnalak. As the dream weavers continue to weave the dagmay and the tnalak, this cultural legacy will continue to prosper and be preserved for posterity.

Keywords: dreamweaver's, Mandaya, mindanao, Philippine folklore, Tboli

Procedia PDF Downloads 97
744 Long Time Oxidation Behavior of Machined 316 Austenitic Stainless Steel in Primary Water Reactor

Authors: Siyang Wang, Yujin Hu, Xuelin Wang, Wenqian Zhang

Abstract:

Austenitic stainless steels are widely used in nuclear industry to manufacture critical components owing to their excellent corrosion resistance at high temperatures. Almost all the components used in nuclear power plants are produced by surface finishing (surface cold work) such as milling, grinding and so on. The change of surface states induced by machining has great influence on the corrosion behavior. In the present study, long time oxidation behavior of machined 316 austenitic stainless steel exposed to simulated pressure water reactor environment was investigated considering different surface states. Four surface finishes were produced by electro-polishing (P), grinding (G), and two milling (M and M1) processes respectively. Before oxidation, the surface Vickers micro-hardness, surface roughness of each type of sample was measured. Corrosion behavior of four types of sample was studied by using oxidation weight gain method for six oxidation periods. The oxidation time of each period was 120h, 216h, 336h, 504h, 672h and 1344h, respectively. SEM was used to observe the surface morphology of oxide film in several period. The results showed that oxide film on austenitic stainless steel has a duplex-layer structure. The inner oxide film is continuous and compact, while the outer layer is composed of oxide particles. The oxide particle consisted of large particles (nearly micron size) and small particles (dozens of nanometers to a few hundred nanometers). The formation of oxide particle could be significantly affected by the machined surface states. The large particle on cold worked samples (grinding and milling) appeared earlier than electro-polished one, and the milled sample has the largest particle size followed by ground one and electro-polished one. For machined samples, the large particles were almost distributed along the direction of machining marks. Severe exfoliation was observed on one milled surface (M) which had the most heavily cold worked layer, while rare local exfoliation occurred on the ground sample (G) and the other milled sample (M1). The electro-polished sample (P) entirely did not exfoliate.

Keywords: austenitic stainless steel, oxidation, machining, SEM

Procedia PDF Downloads 287
743 Developing Curricula for Signaling and Communication Course at Malaysia Railway Academy (MyRA) through Industrial Collaboration Program

Authors: Mohd Fairus Humar, Ibrahim Sulaiman, Pedro Cruz, Hasry Harun

Abstract:

This paper presents the propose knowledge transfer program on railway signaling and communication by Original Equipment Manufacturer (OEM) Thales Portugal. The fundamental issue is that there is no rail related course offered by local universities and colleges in Malaysia which could be an option to pursue student career path. Currently, dedicated trainings related to the rail technology are provided by in-house training academies established by the respective rail operators such as Malaysia Railway Academy (MyRA) and Rapid Rail Training Centre. In this matter, the content of training and facilities need to be strengthened to keep up-to-date with the dynamic evolvement of the rail technology. This is because rail products have evolved to be more sophisticated and embedded with high technology components which no longer exist in the mechanical form alone but combined with electronics, information technology and others. These demand for a workforce imbued with knowledge, multi-skills and competency to deal with specialized technical areas. Talent is needed to support sustainability in Southeast Asia. Keeping the above factors in mind, an Industrial Collaboration Program (ICP) was carried out to transfer knowledge on curricula of railway signaling and communication to a selected railway operators and tertiary educational institution in Malaysia. In order to achieve the aim, a partnership was formed between Technical Depository Agency (TDA), Thales Portugal and MyRA for two years with three main stages of program implementation comprising of: i) training on basic railway signaling and communication for 1 month with Thales in Malaysia; ii) training on advance railway signaling and communication for 4 months with Thales in Portugal and; iii) a series of workshop. Two workshops were convened to develop and harmonize curricula of railway signaling and communication course and were followed by one training for installation equipment of railway signaling and Controlled Train Centre (CTC) system from Thales Portugal. With active involvement from Technical Depository Agency (TDA), railway operators, universities, and colleges, in planning, executing, monitoring, control and closure, the program module of railway signaling and communication course with a lab railway signaling field equipment and CTC simulator were developed. Through this program, contributions from various parties help to build committed societies to engage important issues in relation to railway signaling and communication towards creating a sustainable future.

Keywords: knowledge transfer program, railway signaling and communication, curricula, module and teaching aid simulator

Procedia PDF Downloads 189
742 Assessment of Biochemical Marker Profiles and Their Impact on Morbidity and Mortality of COVID-19 Patients in Tigray, Ethiopia

Authors: Teklay Gebrecherkos, Mahmud Abdulkadir

Abstract:

Abstract: The emergence and subsequent rapid worldwide spread of the COVID-19 pandemic have posed a global crisis, with a tremendously increasing burden of infection, morbidity, and mortality risks. Recent studies have suggested that severe cases of COVID-19 are characterized by massive biochemical, hematological, and inflammatory alterations whose synergistic effect is estimated to progress to multiple organ damage and failure. In this regard, biochemical monitoring of COVID-19 patients, based on comprehensive laboratory assessments and findings, is expected to play a crucial role in effective clinical management and improving the survival rates of patients. However, biochemical markers that can be informative of COVID-19 patient risk stratification and predictor of clinical outcomes are currently scarcely available. The study aims to investigate the profiles of common biochemical markers and their influence on the severity of the COVID-19 infection in Tigray, Ethiopia. Methods: A laboratory-based cross-sectional study was conducted from July to August 2020 at Quiha College of Engineering, Mekelle University COVID-19 isolation and treatment center. Sociodemographic and clinical data were collected using a structured questionnaire. Whole blood was collected from each study participant, and serum samples were separated after being delivered to the laboratory. Hematological biomarkers were analyzed using FACS count, while organ tests and serum electrolytes were analyzed using ion-selective electrode methods using a Cobas-6000 series machine. Data was analyzed using SPSS Vs 20. Results: A total of 120 SARS-CoV-2 patients were enrolled during the study. The participants ranged between 18 and 91 years, with a mean age of 52 (±108.8). The majority (40%) of participants were between the ages of 60 and above. Patients with multiple comorbidities developed severe COVID-19, though not statistically significant (p=0.34). Mann-Whitney U test analysis showed that biochemical tests such as neuropile count (p=0.003), AST levels (p=0.050), serum creatinine (p=0.000), and serum sodium (p=0.015) were significantly correlated with severe COVID-19 disease as compared to non-severe disease. Conclusion: The severity of COVID-19 was associated with higher age, organ tests AST and creatinine, serum Na+, and elevated total neutrophile count. Thus, further study needs to be conducted to evaluate the alterations of biochemical biomarkers and their impact on COVID-19.

Keywords: COVID-19, biomarkers, mortality, Tigray, Ethiopia

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741 Rheological Study of Chitosan/Montmorillonite Nanocomposites: The Effect of Chemical Crosslinking

Authors: K. Khouzami, J. Brassinne, C. Branca, E. Van Ruymbeke, B. Nysten, G. D’Angelo

Abstract:

The development of hybrid organic-inorganic nanocomposites has recently attracted great interest. Typically, polymer silicates represent an emerging class of polymeric nanocomposites that offer superior material properties compared to each compound alone. Among these materials, complexes based on silicate clay and polysaccharides are one of the most promising nanocomposites. The strong electrostatic interaction between chitosan and montmorillonite can induce what is called physical hydrogel, where the coordination bonds or physical crosslinks may associate and dissociate reversibly and in a short time. These mechanisms could be the main origin of the uniqueness of their rheological behavior. However, owing to their structure intrinsically heterogeneous and/or the lack of dissipated energy, they are usually brittle, possess a poor toughness and may not have sufficient mechanical strength. Consequently, the properties of these nanocomposites cannot respond to some requirements of many applications in several fields. To address the issue of weak mechanical properties, covalent chemical crosslink bonds can be introduced to the physical hydrogel. In this way, quite homogeneous dually crosslinked microstructures with high dissipated energy and enhanced mechanical strength can be engineered. In this work, we have prepared a series of chitosan-montmorillonite nanocomposites chemically crosslinked by addition of poly (ethylene glycol) diglycidyl ether. This study aims to provide a better understanding of the mechanical behavior of dually crosslinked chitosan-based nanocomposites by relating it to their microstructures. In these systems, the variety of microstructures is obtained by modifying the number of cross-links. Subsequently, a superior uniqueness of the rheological properties of chemically crosslinked chitosan-montmorillonite nanocomposites is achieved, especially at the highest percentage of clay. Their rheological behaviors depend on the clay/chitosan ratio and the crosslinking. All specimens exhibit a viscous rheological behavior over the frequency range investigated. The flow curves of the nanocomposites show a Newtonian plateau at very low shear rates accompanied by a quite complicated nonlinear decrease with increasing the shear rate. Crosslinking induces a shear thinning behavior revealing the formation of network-like structures. Fitting shear viscosity curves via Ostward-De Waele equation disclosed that crosslinking and clay addition strongly affect the pseudoplasticity of the nanocomposites for shear rates γ ̇>20.

Keywords: chitosan, crossliking, nanocomposites, rheological properties

Procedia PDF Downloads 144
740 An Econometric Analysis of the Flat Tax Revolution

Authors: Wayne Tarrant, Ethan Petersen

Abstract:

The concept of a flat tax goes back to at least the Biblical tithe. A progressive income tax was first vociferously espoused in a small, but famous, pamphlet in 1848 (although England had an emergency progressive tax for war costs prior to this). Within a few years many countries had adopted the progressive structure. The flat tax was only reinstated in some small countries and British protectorates until Mart Laar was elected Prime Minister of Estonia in 1992. Since Estonia’s adoption of the flat tax in 1993, many other formerly Communist countries have likewise abandoned progressive income taxes. Economists had expectations of what would happen when a flat tax was enacted, but very little work has been done on actually measuring the effect. With a testbed of 21 countries in this region that currently have a flat tax, much comparison is possible. Several countries have retained progressive taxes, giving an opportunity for contrast. There are also the cases of Czech Republic and Slovakia, which have adopted and later abandoned the flat tax. Further, with over 20 years’ worth of economic history in some flat tax countries, we can begin to do some serious longitudinal study. In this paper we consider many economic variables to determine if there are statistically significant differences from before to after the adoption of a flat tax. We consider unemployment rates, tax receipts, GDP growth, Gini coefficients, and market data where the data are available. Comparisons are made through the use of event studies and time series methods. The results are mixed, but we draw statistically significant conclusions about some effects. We also look at the different implementations of the flat tax. In some countries there are equal income and corporate tax rates. In others the income tax has a lower rate, while in others the reverse is true. Each of these sends a clear message to individuals and corporations. The policy makers surely have a desired effect in mind. We group countries with similar policies, try to determine if the intended effect actually occurred, and then report the results. This is a work in progress, and we welcome the suggestion of variables to consider. Further, some of the data from before the fall of the Iron Curtain are suspect. Since there are new ruling regimes in these countries, the methods of computing different statistical measures has changed. Although we first look at the raw data as reported, we also attempt to account for these changes. We show which data seem to be fictional and suggest ways to infer the needed statistics from other data. These results are reported beside those on the reported data. Since there is debate about taxation structure, this paper can help inform policymakers of change the flat tax has caused in other countries. The work shows some strengths and weaknesses of a flat tax structure. Moreover, it provides beginnings of a scientific analysis of the flat tax in practice rather than having discussion based solely upon theory and conjecture.

Keywords: flat tax, financial markets, GDP, unemployment rate, Gini coefficient

Procedia PDF Downloads 338
739 Rapid Soil Classification Using Computer Vision, Electrical Resistivity and Soil Strength

Authors: Eugene Y. J. Aw, J. W. Koh, S. H. Chew, K. E. Chua, Lionel L. J. Ang, Algernon C. S. Hong, Danette S. E. Tan, Grace H. B. Foo, K. Q. Hong, L. M. Cheng, M. L. Leong

Abstract:

This paper presents a novel rapid soil classification technique that combines computer vision with four-probe soil electrical resistivity method and cone penetration test (CPT), to improve the accuracy and productivity of on-site classification of excavated soil. In Singapore, excavated soils from local construction projects are transported to Staging Grounds (SGs) to be reused as fill material for land reclamation. Excavated soils are mainly categorized into two groups (“Good Earth” and “Soft Clay”) based on particle size distribution (PSD) and water content (w) from soil investigation reports and on-site visual survey, such that proper treatment and usage can be exercised. However, this process is time-consuming and labour-intensive. Thus, a rapid classification method is needed at the SGs. Computer vision, four-probe soil electrical resistivity and CPT were combined into an innovative non-destructive and instantaneous classification method for this purpose. The computer vision technique comprises soil image acquisition using industrial grade camera; image processing and analysis via calculation of Grey Level Co-occurrence Matrix (GLCM) textural parameters; and decision-making using an Artificial Neural Network (ANN). Complementing the computer vision technique, the apparent electrical resistivity of soil (ρ) is measured using a set of four probes arranged in Wenner’s array. It was found from the previous study that the ANN model coupled with ρ can classify soils into “Good Earth” and “Soft Clay” in less than a minute, with an accuracy of 85% based on selected representative soil images. To further improve the technique, the soil strength is measured using a modified mini cone penetrometer, and w is measured using a set of time-domain reflectometry (TDR) probes. Laboratory proof-of-concept was conducted through a series of seven tests with three types of soils – “Good Earth”, “Soft Clay” and an even mix of the two. Validation was performed against the PSD and w of each soil type obtained from conventional laboratory tests. The results show that ρ, w and CPT measurements can be collectively analyzed to classify soils into “Good Earth” or “Soft Clay”. It is also found that these parameters can be integrated with the computer vision technique on-site to complete the rapid soil classification in less than three minutes.

Keywords: Computer vision technique, cone penetration test, electrical resistivity, rapid and non-destructive, soil classification

Procedia PDF Downloads 214
738 Control for Fluid Flow Behaviours of Viscous Fluids and Heat Transfer in Mini-Channel: A Case Study Using Numerical Simulation Method

Authors: Emmanuel Ophel Gilbert, Williams Speret

Abstract:

The control for fluid flow behaviours of viscous fluids and heat transfer occurrences within heated mini-channel is considered. Heat transfer and flow characteristics of different viscous liquids, such as engine oil, automatic transmission fluid, one-half ethylene glycol, and deionized water were numerically analyzed. Some mathematical applications such as Fourier series and Laplace Z-Transforms were employed to ascertain the behaviour-wave like structure of these each viscous fluids. The steady, laminar flow and heat transfer equations are reckoned by the aid of numerical simulation technique. Further, this numerical simulation technique is endorsed by using the accessible practical values in comparison with the anticipated local thermal resistances. However, the roughness of this mini-channel that is one of the physical limitations was also predicted in this study. This affects the frictional factor. When an additive such as tetracycline was introduced in the fluid, the heat input was lowered, and this caused pro rata effect on the minor and major frictional losses, mostly at a very minute Reynolds number circa 60-80. At this ascertained lower value of Reynolds numbers, there exists decrease in the viscosity and minute frictional losses as a result of the temperature of these viscous liquids been increased. It is inferred that the three equations and models are identified which supported the numerical simulation via interpolation and integration of the variables extended to the walls of the mini-channel, yields the utmost reliance for engineering and technology calculations for turbulence impacting jets in the near imminent age. Out of reasoning with a true equation that could support this control for the fluid flow, Navier-stokes equations were found to tangential to this finding. Though, other physical factors with respect to these Navier-stokes equations are required to be checkmated to avoid uncertain turbulence of the fluid flow. This paradox is resolved within the framework of continuum mechanics using the classical slip condition and an iteration scheme via numerical simulation method that takes into account certain terms in the full Navier-Stokes equations. However, this resulted in dropping out in the approximation of certain assumptions. Concrete questions raised in the main body of the work are sightseen further in the appendices.

Keywords: frictional losses, heat transfer, laminar flow, mini-channel, number simulation, Reynolds number, turbulence, viscous fluids

Procedia PDF Downloads 176
737 Cyclocoelids (Trematoda: Echinostomata) from Gadwall Mareca strepera in the South of the Russian Far East

Authors: Konstantin S. Vainutis, Mark E. Andreev, Anastasia N. Voronova, Mikhail Yu. Shchelkanov

Abstract:

Introduction: The trematodes from the family Cyclocoelidae (cyclocoelids) belong to the superfamily Echinostomatoidea infecting air sacs and trachea of wild birds. At present, the family Cyclocoelidae comprises nine valid genera in three subfamilies: Cyclocoelinae (type taxon), Haematotrephinae, and Typhlocoelinae. To our best knowledge, in this study, molecular genetic methods were used for the first time for studying cyclocoelids from the Russian Far East. Here we provide the data on the morphology and phylogeny of cyclocoelids from gadwall from the Russian Far East. The morphological and genetic data obtained for cyclocoelids indicated the necessity to revise the previously proposed classification within the family Cyclocoelidae. Objectives: The first objective was performing the morphological study of cyclocoelids found in M. strepera from the Russian Far East. The second objective is to reconstruct the phylogenetic relationships of the studied trematodes with other cyclocoelids using the 28S gene. Material and methods: During the field studies in the Khasansky district of the Primorsky region, 21 cyclocoelids were recovered from the air sacs of a single gadwall Mareca strepera. Seven samples of cyclocoelids were overstained in alum carmine, dehydrated in a graded ethanol series, cleared in clove oil, and mounted in Canada balsam. Genomic DNA was extracted from four cyclocoelids using the alkaline lysis method HotShot. The 28S rDNA fragment was amplified using the forward primer Digl2 and the reverse primer 1500R. Results: According to morphological features (ovary intratesticular, forming a triangle with the testes), the studied worms belong to the subfamily Cyclocoelinae Stossich, 1902. In particular, the highest morphological similarity was observed in relation to the trematodes of the genus Cyclocoelum Brandes, 1892 – genital pores are pharyngeal. However, the genetic analysis has shown significant discrepancies between the trematodes studied regarding the genus Cyclocoelum. On the phylogenetic tree, these trematodes took the sister position in relation to the genus Morishitium (previously considered in the subfamily Szidatitrematinae). Conclusion: Based on the results of the morphological and genetic studies, cyclocoelids isolated from Mareca strepera are suggested to be described in the previously unknown genus and differentiated from the type genus Cyclocoelum of the type subfamily Cyclocoelinae. Considering the available molecular data, including described cyclocoelids, the family Cyclocoelidae comprises ten valid genera in the three subfamilies mentioned above.

Keywords: new species, trematoda, phylogeny, cyclocoelidae

Procedia PDF Downloads 841
736 The Changing Landscape of Fire Safety in Covered Car Parks with the Arrival of Electric Vehicles

Authors: Matt Stallwood, Michael Spearpoint

Abstract:

In 2020, the UK government announced that sales of new petrol and diesel cars would end in 2030, and battery-powered cars made up 1 in 8 new cars sold in 2021 – more than the total from the previous five years. The guidance across the UK for the fire safety design of covered car parks is changing in response to the projected rapid growth in electric vehicle (EV) use. This paper discusses the current knowledge on the fire safety concerns posed by EVs, in particular those powered by lithium-ion batteries, when considering the likelihood of vehicle ignition, fire severity and spread of fire to other vehicles. The paper builds on previous work that has investigated the frequency of fires starting in cars powered by internal combustion engines (ICE), the hazard posed by such fires in covered car parks and the potential for neighboring vehicles to become involved in an incident. Historical data has been used to determine the ignition frequency of ICE car fires, whereas such data is scarce when it comes to EV fires. Should a fire occur, then the fire development has conventionally been assessed to match a ‘medium’ growth rate and to have a 95th percentile peak heat release of 9 MW. The paper examines recent literature in which researchers have measured the burning characteristics of EVs to assess whether these values need to be changed. These findings are used to assess the risk posed by EVs when compared to ICE vehicles. The paper examines what new design guidance is being issued by various organizations across the UK, such as fire and rescue services, insurers, local government bodies and regulators and discusses the impact these are having on the arrangement of parking bays, particularly in residential and mixed-use buildings. For example, the paper illustrates how updated guidance published by the Fire Protection Association (FPA) on the installation of sprinkler systems has increased the hazard classification of parking buildings that can have a considerable impact on the feasibility of a building to meet all its design intents when specifying water supply tanks. Another guidance on the provision of smoke ventilation systems and structural fire resistance is also presented. The paper points to where further research is needed on the fire safety risks posed by EVs in covered car parks. This will ensure that any guidance is commensurate with the need to provide an adequate level of life and property safety in the built environment.

Keywords: covered car parks, electric vehicles, fire safety, risk

Procedia PDF Downloads 72
735 Synthesis of Multi-Functional Iron Oxide Nanoparticles for Targeted Drug Delivery in Cancer Treatment

Authors: Masome Moeni, Roya Abedizadeh, Elham Aram, Hamid Sadeghi-Abandansari, Davood Sabour, Robert Menzel, Ali Hassanpour

Abstract:

Significant number of studies and preclinical research in formulation of cancer nano-pharmaceutics have led to an improvement in cancer care. Nonetheless, the antineoplastic agents have ‘failed to live up to its promise’ since their clinical performance is moderately low. For almost ninety years, iron oxide nanoparticles (IONPS) have managed to keep its reputation in clinical application due to their low toxicity, versatility and multi-modal capabilities. Drug Administration approved utilization of IONPs for diagnosis of cancer as contrast media in magnetic resonance imaging, as heat mediator in magnetic hyperthermia and for the treatment of iron deficiency. Furthermore, IONPs have high drug-loading capacity, which makes them good candidates as therapeutic agent transporters. There are yet challenges to overcome for successful clinical application of IONPs, including stability of drug and poor delivery, which might lead to (i) drug resistance, (ii) shorter blood circulation time, and (iii) rapid elimination and adverse side effects from the system. In this study, highly stable and super paramagnetic IONPs were prepared for efficient and targeted drug delivery in cancer treatment. The synthesis procedure was briefly involved the production of IONPs via co-precipitation followed by coating with tetraethyl orthosilicate and 3-aminopropylethoxysilane and grafting with folic acid for stability targeted purposes and controlled drug release. Physiochemical and morphological properties of modified IONPs were characterised using different analytical techniques. The resultant IONPs exhibited clusters of 10 nm spherical shape crystals with less than 100 nm size suitable for drug delivery. The functionalized IONP showed mesoporous features, high stability, dispersibility and crystallinity. Subsequently, the functionalized IONPs were successfully loaded with oxaliplatin, a chemotherapeutic agent, for a controlled drug release in an actively targeting cancer cells. FT-IR observations confirmed presence of oxaliplatin functional groups, while ICP-MS results verified the drug loading was ~ 1.3%.

Keywords: cancer treatment, chemotherapeutic agent, drug delivery, iron oxide, multi-functional nanoparticle

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734 Properties and Microstructure of Scaled-Up MgO Concrete Blocks Incorporating Fly Ash or Ground Granulated Blast-Furnace Slag

Authors: L. Pu, C. Unluer

Abstract:

MgO cements have the potential to sequester CO2 in construction products, and can be partial or complete replacement of PC in concrete. Construction block is a promising application for reactive MgO cements. Main advantages of blocks are: (i) suitability for sequestering CO2 due to their initially porous structure; (ii) lack of need for in-situ treatment as carbonation can take place during fabrication; and (iii) high potential for commercialization. Both strength gain and carbon sequestration of MgO cements depend on carbonation process. Fly ash and ground granulated blast-furnace slag (GGBS) are pozzolanic material and are proved to improve many of the performance characteristics of the concrete, such as strength, workability, permeability, durability and corrosion resistance. A very limited amount of work has been reported on the production of MgO blocks on a large scale so far. A much more extensive study, wherein blocks with different mix design is needed to verify the feasibility of commercial production. The changes in the performance of the samples were evaluated by compressive strength testing. The properties of the carbonation products were identified by X-ray diffraction (XRD) and scanning electron microscopy (SEM)/ field emission scanning electron microscopy (FESEM), and the degree of carbonation was obtained by thermogravimetric analysis (TGA), XRD and energy dispersive X-ray (EDX). The results of this study enabled the understanding the relationship between lab-scale samples and scale-up blocks based on their mechanical performance and microstructure. Results indicate that for both scaled-up and lab-scale samples, MgO samples always had the highest strength results, followed by MgO-fly ash samples and MgO-GGBS had relatively lowest strength. The lower strength of MgO with fly ash/GGBS samples at early stage is related to the relatively slow hydration process of pozzolanic materials. Lab-scale cubic samples were observed to have higher strength results than scaled-up samples. The large size of the scaled-up samples made it more difficult to let CO2 to reach inner part of the samples and less carbonation products formed. XRD, TGA and FESEM/EDX results indicate the existence of brucite and HMCs in MgO samples, M-S-H, hydrotalcite in the MgO-fly ash samples and C-S-H, hydrotalctie in the MgO-GGBS samples. Formation of hydration products (M-S-H, C-S-H, hydrotalcite) and carbonation products (hydromagnecite, dypingite) increased with curing duration, which is the reason of increasing strength. This study verifies the advantage of large-scale MgO blocks over common PC blocks and the feasibility of commercial production of MgO blocks.

Keywords: reactive MgO, fly ash, ground granulated blast-furnace slag, carbonation, CO₂

Procedia PDF Downloads 191
733 Investigating the Influence of Activation Functions on Image Classification Accuracy via Deep Convolutional Neural Network

Authors: Gulfam Haider, sana danish

Abstract:

Convolutional Neural Networks (CNNs) have emerged as powerful tools for image classification, and the choice of optimizers profoundly affects their performance. The study of optimizers and their adaptations remains a topic of significant importance in machine learning research. While numerous studies have explored and advocated for various optimizers, the efficacy of these optimization techniques is still subject to scrutiny. This work aims to address the challenges surrounding the effectiveness of optimizers by conducting a comprehensive analysis and evaluation. The primary focus of this investigation lies in examining the performance of different optimizers when employed in conjunction with the popular activation function, Rectified Linear Unit (ReLU). By incorporating ReLU, known for its favorable properties in prior research, the aim is to bolster the effectiveness of the optimizers under scrutiny. Specifically, we evaluate the adjustment of these optimizers with both the original Softmax activation function and the modified ReLU activation function, carefully assessing their impact on overall performance. To achieve this, a series of experiments are conducted using a well-established benchmark dataset for image classification tasks, namely the Canadian Institute for Advanced Research dataset (CIFAR-10). The selected optimizers for investigation encompass a range of prominent algorithms, including Adam, Root Mean Squared Propagation (RMSprop), Adaptive Learning Rate Method (Adadelta), Adaptive Gradient Algorithm (Adagrad), and Stochastic Gradient Descent (SGD). The performance analysis encompasses a comprehensive evaluation of the classification accuracy, convergence speed, and robustness of the CNN models trained with each optimizer. Through rigorous experimentation and meticulous assessment, we discern the strengths and weaknesses of the different optimization techniques, providing valuable insights into their suitability for image classification tasks. By conducting this in-depth study, we contribute to the existing body of knowledge surrounding optimizers in CNNs, shedding light on their performance characteristics for image classification. The findings gleaned from this research serve to guide researchers and practitioners in making informed decisions when selecting optimizers and activation functions, thus advancing the state-of-the-art in the field of image classification with convolutional neural networks.

Keywords: deep neural network, optimizers, RMsprop, ReLU, stochastic gradient descent

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732 An Analytical Systematic Design Approach to Evaluate Ballistic Performance of Armour Grade AA7075 Aluminium Alloy Using Friction Stir Processing

Authors: Lahari Ramya Pa, Sudhakar Ib, Madhu Vc, Madhusudhan Reddy Gd, Srinivasa Rao E.

Abstract:

Selection of suitable armor materials for defense applications is very crucial with respect to increasing mobility of the systems as well as maintaining safety. Therefore, determining the material with the lowest possible areal density that resists the predefined threat successfully is required in armor design studies. A number of light metal and alloys are come in to forefront especially to substitute the armour grade steels. AA5083 aluminium alloy which fit in to the military standards imposed by USA army is foremost nonferrous alloy to consider for possible replacement of steel to increase the mobility of armour vehicles and enhance fuel economy. Growing need of AA5083 aluminium alloy paves a way to develop supplement aluminium alloys maintaining the military standards. It has been witnessed that AA 2xxx aluminium alloy, AA6xxx aluminium alloy and AA7xxx aluminium alloy are the potential material to supplement AA5083 aluminium alloy. Among those cited aluminium series alloys AA7xxx aluminium alloy (heat treatable) possesses high strength and can compete with armour grade steels. Earlier investigations revealed that layering of AA7xxx aluminium alloy can prevent spalling of rear portion of armour during ballistic impacts. Hence, present investigation deals with fabrication of hard layer (made of boron carbide) i.e. layer on AA 7075 aluminium alloy using friction stir processing with an intention of blunting the projectile in the initial impact and backing tough portion(AA7xxx aluminium alloy) to dissipate residual kinetic energy. An analytical approach has been adopted to unfold the ballistic performance of projectile. Penetration of projectile inside the armour has been resolved by considering by strain energy model analysis. Perforation shearing areas i.e. interface of projectile and armour is taken in to account for evaluation of penetration inside the armour. Fabricated surface composites (targets) were tested as per the military standard (JIS.0108.01) in a ballistic testing tunnel at Defence Metallurgical Research Laboratory (DMRL), Hyderabad in standardized testing conditions. Analytical results were well validated with experimental obtained one.

Keywords: AA7075 aluminium alloy, friction stir processing, boron carbide, ballistic performance, target

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731 Computational Characterization of Electronic Charge Transfer in Interfacial Phospholipid-Water Layers

Authors: Samira Baghbanbari, A. B. P. Lever, Payam S. Shabestari, Donald Weaver

Abstract:

Existing signal transmission models, although undoubtedly useful, have proven insufficient to explain the full complexity of information transfer within the central nervous system. The development of transformative models will necessitate a more comprehensive understanding of neuronal lipid membrane electrophysiology. Pursuant to this goal, the role of highly organized interfacial phospholipid-water layers emerges as a promising case study. A series of phospholipids in neural-glial gap junction interfaces as well as cholesterol molecules have been computationally modelled using high-performance density functional theory (DFT) calculations. Subsequent 'charge decomposition analysis' calculations have revealed a net transfer of charge from phospholipid orbitals through the organized interfacial water layer before ultimately finding its way to cholesterol acceptor molecules. The specific pathway of charge transfer from phospholipid via water layers towards cholesterol has been mapped in detail. Cholesterol is an essential membrane component that is overrepresented in neuronal membranes as compared to other mammalian cells; given this relative abundance, its apparent role as an electronic acceptor may prove to be a relevant factor in further signal transmission studies of the central nervous system. The timescales over which this electronic charge transfer occurs have also been evaluated by utilizing a system design that systematically increases the number of water molecules separating lipids and cholesterol. Memory loss through hydrogen-bonded networks in water can occur at femtosecond timescales, whereas existing action potential-based models are limited to micro or nanosecond scales. As such, the development of future models that attempt to explain faster timescale signal transmission in the central nervous system may benefit from our work, which provides additional information regarding fast timescale energy transfer mechanisms occurring through interfacial water. The study possesses a dataset that includes six distinct phospholipids and a collection of cholesterol. Ten optimized geometric characteristics (features) were employed to conduct binary classification through an artificial neural network (ANN), differentiating cholesterol from the various phospholipids. This stems from our understanding that all lipids within the first group function as electronic charge donors, while cholesterol serves as an electronic charge acceptor.

Keywords: charge transfer, signal transmission, phospholipids, water layers, ANN

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