Search results for: unsymmetrical operation point
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7508

Search results for: unsymmetrical operation point

2528 Impact of Climate Change on Forest Ecosystem Services: In situ Biodiversity Conservation and Sustainable Management of Forest Resources in Tropical Forests

Authors: Rajendra Kumar Pandey

Abstract:

Forest genetic resources not only represent regional biodiversity but also have immense value as the wealth for securing livelihood of poor people. These are vulnerable to ecological due to depletion/deforestation and /or impact of climate change. These resources of various plant categories are vulnerable on the floor of natural tropical forests, and leading to the threat on the growth and development of future forests. More than 170 species, including NTFPs, are in critical condition for their survival in natural tropical forests of Central India. Forest degradation, commensurate with biodiversity loss, is now pervasive, disproportionately affecting the rural poor who directly depend on forests for their subsistence. Looking ahead the interaction between forest and water, soil, precipitation, climate change, etc. and its impact on biodiversity of tropical forests, it is inevitable to develop co-operation policies and programmes to address new emerging realities. Forests ecosystem also known as the 'wealth of poor' providing goods and ecosystem services on a sustainable basis, are now recognized as a stepping stone to move poor people beyond subsistence. Poverty alleviation is the prime objective of the Millennium Development Goals (MDGs). However, environmental sustainability including other MDGs, is essential to ensure successful elimination of poverty and well being of human society. Loss and degradation of ecosystem are the most serious threats to achieving development goals worldwide. Millennium Ecosystem Assessment (MEA, 2005) was an attempt to identify provisioning and regulating cultural and supporting ecosystem services to provide livelihood security of human beings. Climate change may have a substantial impact on ecological structure and function of forests, provisioning, regulations and management of resources which can affect sustainable flow of ecosystem services. To overcome these limitations, policy guidelines with respect to planning and consistent research strategy need to be framed for conservation and sustainable development of forest genetic resources.

Keywords: climate change, forest ecosystem services, sustainable forest management, biodiversity conservation

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2527 Phytoremediation of Pharmaceutical Emerging Contaminant-Laden Wastewater: A Techno-Economic and Sustainable Development Approach

Authors: Reda A. Elkhyat, Mahmoud Nasr, Amel A. Tammam, Mohamed A. Ghazy

Abstract:

Pharmaceuticals and personal care products (PPCPs) are a unique group of emerging contaminants continuously introduced into the aquatic ecosystem at concentrations capable of inducing adverse effects on humans and aquatic organisms, even at trace levels ranging from ppt to ppm. Amongst the common pharmaceutical emerging pollutants detected in several aquatic environments, acetaminophen has been recognized for its high toxicity. Once released into the aquatic environment, acetaminophen could be degraded by the microbial community and adsorption/ uptake by the plants. Although many studies have investigated the hazard risks of acetaminophen pollutants on aquatic animals, the number of studies demonstrating its removal efficiency and effects on the aquatic plant still needs to be expanded. In this context, this study aims to apply the aquatic plant-based phytoremediation system to eliminate this emerging contaminant from domestic wastewater. The phytoremediation experiment was performed in a hydroponic system containing Eichhornia crassipes and operated under the natural environment at 25°C to 30°C. This system was subjected to synthetic domestic wastewater with the maximum initial chemical oxygen demand (COD) of 390 mg/L and three different acetaminophen concentrations of 25, 50, and 200 mg/L. After 17 d of operation, the phytoremediation system achieved removal efficiencies of about 100% and 85.6±4.2% for acetaminophen and COD, respectively.Moreover, the Eichhornia crassipes could withstand the toxicity associated with increasing the acetaminophen concentrations from 25 to 200 mg/L. This high treatment performance could be assigned to the well-adaptation of the water hyacinth to the phytoremediation factors. Moreover, it has been proposed that this phytoremediation system could be largely supported by phytodegradation and plant uptaking mechanisms; however, detecting the generated intermediates, metabolites, and degradation products are still under investigation. Applying this free-floating plant in wastewater treatment and reducing emerging contaminants would meet the targets of SDGs 3, 6, and. 14. The cost-benefit analysis was performed for the phytoremediation system. The phytoremediation system is financially viable as the net profit was 2921 US $/ y with a payback period of nine years.

Keywords: domestic wastewater, emerging pollutants, hydrophyte Eichhornia crassipes, paracetamol removal efficiency, sustainable development goals (SDGs)

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2526 The Analysis of Drill Bit Optimization by the Application of New Electric Impulse Technology in Shallow Water Absheron Peninsula

Authors: Ayshan Gurbanova

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Despite based on the fact that drill bit which is the smallest part of bottom hole assembly costs only in between 10% and 15% of the total expenses made, they are the first equipment that is in contact with the formation itself. Hence, it is consequential to choose the appropriate type and dimension of drilling bit, which will prevent majority of problems by not demanding many tripping procedure. However, within the advance in technology, it is now seamless to be beneficial in the terms of many concepts such as subsequent time of operation, energy, expenditure, power and so forth. With the intention of applying the method to Azerbaijan, the field of Shallow Water Absheron Peninsula has been suggested, where the mainland has been located 15 km away from the wildcat wells, named as “NKX01”. It has the water depth of 22 m as indicated. In 2015 and 2016, the seismic survey analysis of 2D and 3D have been conducted in contract area as well as onshore shallow water depth locations. With the aim of indicating clear elucidation, soil stability, possible submersible dangerous scenarios, geohazards and bathymetry surveys have been carried out as well. Within the seismic analysis results, the exact location of exploration wells have been determined and along with this, the correct measurement decisions have been made to divide the land into three productive zones. In the term of the method, Electric Impulse Technology (EIT) is based on discharge energies of electricity within the corrosivity in rock. Take it simply, the highest value of voltages could be created in the less range of nano time, where it is sent to the rock through electrodes’ baring as demonstrated below. These electrodes- higher voltage powered and grounded are placed on the formation which could be obscured in liquid. With the design, it is more seamless to drill horizontal well based on the advantage of loose contact of formation. There is also no chance of worn ability as there are no combustion, mechanical power exist. In the case of energy, the usage of conventional drilling accounts for 1000 𝐽/𝑐𝑚3 , where this value accounts for between 100 and 200 𝐽/𝑐𝑚3 in EIT. Last but not the least, from the test analysis, it has been yielded that it achieves the value of ROP more than 2 𝑚/ℎ𝑟 throughout 15 days. Taking everything into consideration, it is such a fact that with the comparison of data analysis, this method is highly applicable to the fields of Azerbaijan.

Keywords: drilling, drill bit cost, efficiency, cost

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2525 Damage Detection in a Cantilever Beam under Different Excitation and Temperature Conditions

Authors: A. Kyprianou, A. Tjirkallis

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Condition monitoring of structures in service is very important as it provides information about the risk of damage development. One of the essential constituents of structural condition monitoring is the damage detection methodology. In the context of condition monitoring of in service structures a damage detection methodology analyses data obtained from the structure while it is in operation. Usually, this means that the data could be affected by operational and environmental conditions in a way that could mask the effects of a possible damage on the data. This, depending on the damage detection methodology, could lead to either false alarms or miss existing damages. In this article a damage detection methodology that is based on the Spatio-temporal continuous wavelet transform (SPT-CWT) analysis of a sequence of experimental time responses of a cantilever beam is proposed. The cantilever is subjected to white and pink noise excitation to simulate different operating conditions. In addition, in order to simulate changing environmental conditions, the cantilever is subjected to heating by a heat gun. The response of the cantilever beam is measured by a high-speed camera. Edges are extracted from the series of images of the beam response captured by the camera. Subsequent processing of the edges gives a series of time responses on 439 points on the beam. This sequence is then analyzed using the SPT-CWT to identify damage. The algorithm proposed was able to clearly identify damage under any condition when the structure was excited by white noise force. In addition, in the case of white noise excitation, the analysis could also reveal the position of the heat gun when it was used to heat the structure. The analysis could identify the different operating conditions i.e. between responses due to white noise excitation and responses due to pink noise excitation. During the pink noise excitation whereas damage and changing temperature were identified it was not possible to clearly identify the effect of damage from that of temperature. The methodology proposed in this article for damage detection enables the separation the damage effect from that due to temperature and excitation on data obtained from measurements of a cantilever beam. This methodology does not require information about the apriori state of the structure.

Keywords: spatiotemporal continuous wavelet transform, damage detection, data normalization, varying temperature

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2524 Diagnostic Efficacy and Usefulness of Digital Breast Tomosynthesis (DBT) in Evaluation of Breast Microcalcifications as a Pre-Procedural Study for Stereotactic Biopsy

Authors: Okhee Woo, Hye Seon Shin

Abstract:

Purpose: To investigate the diagnostic power of digital breast tomosynthesis (DBT) in evaluation of breast microcalcifications and usefulness as a pre-procedural study for stereotactic biopsy in comparison with full-field digital mammogram (FFDM) and FFDM plus magnification image (FFDM+MAG). Methods and Materials: An IRB approved retrospective observer performance study on DBT, FFDM, and FFDM+MAG was done. Image quality was rated in 5-point scoring system for lesion clarity (1, very indistinct; 2, indistinct; 3, fair; 4, clear; 5, very clear) and compared by Wilcoxon test. Diagnostic power was compared by diagnostic values and AUC with 95% confidence interval. Additionally, procedural report of biopsy was analysed for patient positioning and adequacy of instruments. Results: DBT showed higher lesion clarity (median 5, interquartile range 4-5) than FFDM (3, 2-4, p-value < 0.0001), and no statistically significant difference to FFDM+MAG (4, 4-5, p-value=0.3345). Diagnostic sensitivity and specificity of DBT were 86.4% and 92.5%; FFDM 70.4% and 66.7%; FFDM+MAG 93.8% and 89.6%. The AUCs of DBT (0.88) and FFDM+MAG (0.89) were larger than FFDM (0.59, p-values < 0.0001) but there was no statistically significant difference between DBT and FFDM+MAG (p-value=0.878). In 2 cases with DBT, petit needle could be appropriately prepared; and other 3 without DBT, patient repositioning was needed. Conclusion: DBT showed better image quality and diagnostic values than FFDM and equivalent to FFDM+MAG in the evaluation of breast microcalcifications. Evaluation with DBT as a pre-procedural study for breast stereotactic biopsy can lead to more accurate localization and successful biopsy and also waive the need for additional magnification images.

Keywords: DBT, breast cancer, stereotactic biopsy, mammography

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2523 Exergetic Optimization on Solid Oxide Fuel Cell Systems

Authors: George N. Prodromidis, Frank A. Coutelieris

Abstract:

Biogas can be currently considered as an alternative option for electricity production, mainly due to its high energy content (hydrocarbon-rich source), its renewable status and its relatively low utilization cost. Solid Oxide Fuel Cell (SOFC) stacks convert fuel’s chemical energy to electricity with high efficiencies and reveal significant advantages on fuel flexibility combined with lower emissions rate, especially when utilize biogas. Electricity production by biogas constitutes a composite problem which incorporates an extensive parametric analysis on numerous dynamic variables. The main scope of the presented study is to propose a detailed thermodynamic model on the optimization of SOFC-based power plants’ operation based on fundamental thermodynamics, energy and exergy balances. This model named THERMAS (THERmodynamic MAthematical Simulation model) incorporates each individual process, during electricity production, mathematically simulated for different case studies that represent real life operational conditions. Also, THERMAS offers the opportunity to choose a great variety of different values for each operational parameter individually, thus allowing for studies within unexplored and experimentally impossible operational ranges. Finally, THERMAS innovatively incorporates a specific criterion concluded by the extensive energy analysis to identify the most optimal scenario per simulated system in exergy terms. Therefore, several dynamical parameters as well as several biogas mixture compositions have been taken into account, to cover all the possible incidents. Towards the optimization process in terms of an innovative OPF (OPtimization Factor), presented here, this research study reveals that systems supplied by low methane fuels can be comparable to these supplied by pure methane. To conclude, such an innovative simulation model indicates a perspective on the optimal design of a SOFC stack based system, in the direction of the commercialization of systems utilizing biogas.

Keywords: biogas, exergy, efficiency, optimization

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2522 A Critical Appraisal of the Philosophy of University and Its Debates: The Creation of Disempowered Youth in the Ethiopian Education Sector

Authors: Sisaye Tamrat Ayalew

Abstract:

This paper focuses on the educational philosophy of universities in Ethiopia and the debates surrounding it. It highlights the contradictory views on the role of universities, with some perceiving them as practical problem-solving institutions and others emphasizing the production and dissemination of knowledge. The aim of this study is to critically explore the debates around the educational philosophy of universities in Ethiopia. It also seeks to examine how the understanding of this philosophy contributes to the marginalization of youth in the country. This research adopts a phenomenological qualitative research design. It aims to understand the impact of socio-economic and political factors on university education and how youth from disadvantaged backgrounds experience marginalization in the job market. The study reveals that the understanding of educational philosophy varies across different contexts and over time. In the Ethiopian context, the philosophy of universities lacks a disinterested pursuit of knowledge and instrumentalist epistemology. Instead, it oversimplifies the philosophy to the point of devaluing knowledge and treating certificates as commodities, even in the absence of formal training. In conclusion, this research highlights the need for a critical appraisal of the educational philosophy of universities in Ethiopia. It emphasizes the negative impact of an oversimplified and commodified approach to knowledge on the empowerment of youth. By bringing attention to these issues, this study contributes to the broader understanding of the role of universities in society and calls for reforms in the Ethiopian education sector to promote empowerment rather than disempowerment.

Keywords: philosophy of universities, marginalized youth, diploma mill, instrumentalist epistemology, disinterested pursuit

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2521 Cows Milk Quality on Different Sized Dairy Farms

Authors: Ramutė Miseikienė, Saulius Tusas

Abstract:

Somatic cell count and bacteria count are the main indicators of cow milk quality. The aim of this study was to analyze and compare parameters of milk quality in different-sized cows herds. Milk quality of ten dairy cows farms during one year period was analyzed. Dairy farms were divided into five groups according to number of cows in the farm (under 50 cows, 51–100 cows, 101–200 cows, 201–400 cows and more than 400 cows). The averages of somatic cells bacteria count in milk and milk freezing temperature were analyzed. Also, these parameters of milk quality were compared during outdoor (from May to September) and indoor (from October to April) periods. The largest number of SCC was established in the smallest farms, i.e., in farms under 50 cows and 51-100 cows (respectively 264±9,19 and 300±10,24 thousand/ml). Reliable link between the smallest and largest dairy farms and farms with 101-200 and 201-400 cows and count of somatic cells in milk has not been established (P > 0.05). Bacteria count had a low tendency to decrease when the number of cows in farms increased. The highest bacteria number was determined in the farms with 51-100 cows and the the lowest bacteria count was in milk when 201-400 and more than 401 cows were kept. With increasing the number of cows milk maximal freezing temperature decreases (significant negative trend), i. e, indicator is improving. It should be noted that in all farms milk freezing point never exceeded requirements (-0.515 °C). The highest difference between SCC in milk during the indoor and outdoor periods was established in farms with 201-400 cows (respectively 218.49 thousand/ml and 268.84 thousand/ml). However, the count of SC was significantly higher (P < 0.05) during outdoor period in large farms (201-400 and more cows). There was no significant difference between bacteria count in milk during both – outdoor and indoor – periods (P > 0.05).

Keywords: bacteria, cow, farm size, somatic cell count

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2520 Self-Disclosure and Privacy Management Behavior in Social Media: Privacy Calculus Perspective

Authors: Chien-Wen Chen, Nguyen Duong Thuy Trang, Yu-Hsuan Chang

Abstract:

With the development of information technology, social networking sites are inseparable from life and have become an important way for people to communicate. Nonetheless, privacy issues are raised by the presence of personal information on social networking sites. However, users can benefit from using the functions of social networking sites, which also leads to users worrying about the leakage of personal information without corresponding privacy protection behaviors, which is called the privacy paradox. However, previous studies have questioned the viewpoint of the privacy paradox, believing that users are not so naive and that people with privacy concerns will conduct privacy management. Consequently, this study is based on the view of privacy calculation perspective to investigate the privacy behavior of users on social networking sites. Among them, social benefits and privacy concerns are taken as the expected benefits and costs in the viewpoint of privacy calculation. At the same time, this study also explores the antecedents, including positive feedback, self-presentation, privacy policy, and information sensitivity, and the consequence of privacy behavior of weighing benefits and costs, including self-disclosure and three privacy management strategies by interpersonal boundaries (Preventive, Censorship, and Corrective). The survey respondents' characteristics and prior use experience of social networking sites were analyzed. As a consequence, a survey of 596 social network users was conducted online to validate the research framework. The results show that social benefit has the greatest influence on privacy behavior. The most important external factors affecting privacy behavior are positive feedback, followed by the privacy policy and information sensitivity. In addition, the important findings of this study are that social benefits will positively affect privacy management. It shows that users can get satisfaction from interacting with others through social networking sites. They will not only disclose themselves but also manage their privacy on social networking sites after considering social benefits and privacy management on social networking sites, and it expands the adoption of the Privacy Calculus Perspective framework from prior research. Therefore, it is suggested that as the functions of social networking sites increase and the development of social networking sites, users' needs should be understood and updated in order to ensure the sustainable operation of social networking.

Keywords: privacy calculus perspective, self-disclosure, privacy management, social benefit, privacy concern

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2519 Buildings Founded on Thermal Insulation Layer Subjected to Earthquake Load

Authors: David Koren, Vojko Kilar

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The modern energy-efficient houses are often founded on a thermal insulation (TI) layer placed under the building’s RC foundation slab. The purpose of the paper is to identify the potential problems of the buildings founded on TI layer from the seismic point of view. The two main goals of the study were to assess the seismic behavior of such buildings, and to search for the critical structural parameters affecting the response of the superstructure as well as of the extruded polystyrene (XPS) layer. As a test building a multi-storeyed RC frame structure with and without the XPS layer under the foundation slab has been investigated utilizing nonlinear dynamic (time-history) and static (pushover) analyses. The structural response has been investigated with reference to the following performance parameters: i) Building’s lateral roof displacements, ii) Edge compressive and shear strains of the XPS, iii) Horizontal accelerations of the superstructure, iv) Plastic hinge patterns of the superstructure, v) Part of the foundation in compression, and vi) Deformations of the underlying soil and vertical displacements of the foundation slab (i.e. identifying the potential uplift). The results have shown that in the case of higher and stiff structures lying on firm soil the use of XPS under the foundation slab might induce amplified structural peak responses compared to the building models without XPS under the foundation slab. The analysis has revealed that the superstructure as well as the XPS response is substantially affected by the stiffness of the foundation slab.

Keywords: extruded polystyrene (XPS), foundation on thermal insulation, energy-efficient buildings, nonlinear seismic analysis, seismic response, soil–structure interaction

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2518 The Reasons and the Practical Benefits Behind the Motivation of Businesses to Participate in the Dual Education System (DLS)

Authors: Ainur Bulasheva

Abstract:

During the last decade, the dual learning system (DLS) has been actively introduced in various industries in Kazakhstan, including both vocational, post-secondary, and higher education levels. It is a relatively new practice-oriented approach to training qualified personnel in Kazakhstan, officially introduced in 2012. Dual learning was integrated from the German vocational education and training system, combining practical training with part-time work in production and training in an educational institution. The policy of DLS has increasingly focused on decreasing youth unemployment and the shortage of mid-level professionals by providing incentives for employers to involve in this system. By participating directly in the educational process, the enterprise strives to train its future personnel to meet fast-changing market demands. This study examines the effectiveness of DLS from the perspective of employers to understand the motivations of businesses to participate (invest) in this program. The human capital theory of Backer, which predicts that employers will invest in training their workers (in our case, dual students) when they expect that the return on investment will be greater than the cost - acts as a starting point. Further extensionists of this theory will be considered to understand investing intentions of businesses. By comparing perceptions of DLS employers and non-dual practices, this study determines the efficiency of promoted training approach for enterprises in the Kazakhstan agri-food industry.

Keywords: vocational and technical education, dualeducation, human capital theory, argi-food industry

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2517 Predicting the Next Offensive Play Types will be Implemented to Maximize the Defense’s Chances of Success in the National Football League

Authors: Chris Schoborg, Morgan C. Wang

Abstract:

In the realm of the National Football League (NFL), substantial dedication of time and effort is invested by both players and coaches in meticulously analyzing the game footage of their opponents. The primary aim is to anticipate the actions of the opposing team. Defensive players and coaches are especially focused on deciphering their adversaries' intentions to effectively counter their strategies. Acquiring insights into the specific play type and its intended direction on the field would confer a significant competitive advantage. This study establishes pre-snap information as the cornerstone for predicting both the play type (e.g., deep pass, short pass, or run) and its spatial trajectory (right, left, or center). The dataset for this research spans the regular NFL season data for all 32 teams from 2013 to 2022. This dataset is acquired using the nflreadr package, which conveniently extracts play-by-play data from NFL games and imports it into the R environment as structured datasets. In this study, we employ a recently developed machine learning algorithm, XGBoost. The final predictive model achieves an impressive lift of 2.61. This signifies that the presented model is 2.61 times more effective than random guessing—a significant improvement. Such a model has the potential to markedly enhance defensive coaches' ability to formulate game plans and adequately prepare their players, thus mitigating the opposing offense's yardage and point gains.

Keywords: lift, NFL, sports analytics, XGBoost

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2516 An Integrated Approach to Solid Waste Management of Karachi, Pakistan (Waste-to-Energy Options)

Authors: Engineer Dilnawaz Shah

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Solid Waste Management (SWM) is perhaps one of the most important elements constituting the environmental health and sanitation of the urban developing sector. The management system has several components that are integrated as well as interdependent; thus, the efficiency and effectiveness of the entire system are affected when any of its functional components fails or does not perform up to the level mark of operation. Sindh Solid Waste Management Board (SSWMB) is responsible for the management of solid waste in the entire city. There is a need to adopt the engineered approach in the redesigning of the existing system. In most towns, street sweeping operations have been mechanized and done by machinery operated by vehicles. Construction of Garbage Transfer Stations (GTS) at a number of locations within the city will cut the cost of transportation of waste to disposal sites. Material processing, recovery of recyclables, compaction, volume reduction, and increase in density will enable transportation of waste to disposal sites/landfills via long vehicles (bulk transport), minimizing transport/traffic and environmental pollution-related issues. Development of disposal sites into proper sanitary landfill sites is mandatory. The transportation mechanism is through garbage vehicles using either hauled or fixed container systems employing crew for mechanical or manual loading. The number of garbage vehicles is inadequate, and due to comparatively long haulage to disposal sites, there are certain problems of frequent vehicular maintenance and high fuel costs. Foreign investors have shown interest in enterprising improvement schemes and proposed operating a solid waste management system in Karachi. The waste to Energy option is being considered to provide a practical answer to be adopted to generate power and reduce waste load – a two-pronged solution for the increasing environmental problem. The paper presents results and analysis of a recent study into waste generation and characterization probing into waste-to-energy options for Karachi City.

Keywords: waste to energy option, integrated approach, solid waste management, physical and chemical composition of waste in Karachi

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2515 Impact of Emotional Intelligence of Principals in High Schools on Teachers Conflict Management: A Case Study on Secondary Schools, Tehran, Iran

Authors: Amir Ahmadi, Hossein Ahmadi, Alireza Ahmadi

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Emotional Intelligence (EI) has been defined as the ability to empathize, persevere, control impulses, communicate clearly, make thoughtful decisions, solve problems, and work with others in a way that earns friends and success. These abilities allow an individual to recognize and regulate emotion, develop self-control, set goals, develop empathy, resolve conflicts, and develop skills needed for leadership and effective group participation. Due to the increasing complexity of organizations and different ways of thinking, attitudes and beliefs of individuals, Conflict as an important part of organizational life has been examined frequently. The main point is that the conflict is not necessarily in organization, unnecessary; But it can be more creative (increase creativity), to promote innovation, or may avoid wasting energy and resources of the organization. The purpose of this study was to investigate the relation between principals emotional intelligence as one of the factors affecting conflict management among teachers. This relation was analyzed through cluster sampling with a sample size consisting of 120 individuals. The results of the study showed that, at the 95% level of confidence, the two secondary hypotheses (i.e. relation between emotional intelligence of principals and use of competition and cooperation strategies of conflict management among teachers)were confirmed, but the other three secondary hypotheses (i.e. the relation between emotional intelligence of managers and use of avoidance, adaptation and adaptability strategies of conflict management among teachers) were rejected. The primary hypothesis (i.e. relation between emotional intelligence of principals with conflict management among teachers) is supported.

Keywords: emotional intelligence, conflict, conflict management, strategies of conflict management

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2514 Assessing Effects of an Intervention on Bottle-Weaning and Reducing Daily Milk Intake from Bottles in Toddlers Using Two-Part Random Effects Models

Authors: Yungtai Lo

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Two-part random effects models have been used to fit semi-continuous longitudinal data where the response variable has a point mass at 0 and a continuous right-skewed distribution for positive values. We review methods proposed in the literature for analyzing data with excess zeros. A two-part logit-log-normal random effects model, a two-part logit-truncated normal random effects model, a two-part logit-gamma random effects model, and a two-part logit-skew normal random effects model were used to examine effects of a bottle-weaning intervention on reducing bottle use and daily milk intake from bottles in toddlers aged 11 to 13 months in a randomized controlled trial. We show in all four two-part models that the intervention promoted bottle-weaning and reduced daily milk intake from bottles in toddlers drinking from a bottle. We also show that there are no differences in model fit using either the logit link function or the probit link function for modeling the probability of bottle-weaning in all four models. Furthermore, prediction accuracy of the logit or probit link function is not sensitive to the distribution assumption on daily milk intake from bottles in toddlers not off bottles.

Keywords: two-part model, semi-continuous variable, truncated normal, gamma regression, skew normal, Pearson residual, receiver operating characteristic curve

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2513 Performance Analysis and Multi-Objective Optimization of a Kalina Cycle for Low-Temperature Applications

Authors: Sadegh Sadeghi, Negar Shabani

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From a thermal point of view, zeotropic mixtures are likely to be more efficient than azeotropic fluids in low-temperature thermodynamic cycles due to their suitable boiling characteristics. In this study, performance of a low-temperature Kalina cycle with R717/water working fluid used in different existing power plants is mathematically investigated. To analyze the behavior of the cycle, mass conservation, energy conservation, and exergy balance equations are presented. With regard to the similarity in molar mass of R717 (17.03 gr/mol) and water (18.01 gr/mol), there is no need to alter the size of Kalina system components such as turbine and pump. To optimize the cycle energy and exergy efficiencies simultaneously, a constrained multi-objective optimization is carried out applying an Artificial Bee Colony algorithm. The main motivation behind using this algorithm lies on its robustness, reliability, remarkable precision and high–speed convergence rate in dealing with complicated constrained multi-objective problems. Convergence rates of the algorithm for calculating the optimal energy and exergy efficiencies are presented. Subsequently, due to the importance of exergy concept in Kalina cycles, exergy destructions occurring in the components are computed. Finally, the impacts of pressure, temperature, mass fraction and mass flow rate on the energy and exergy efficiencies are elaborately studied.

Keywords: artificial bee colony algorithm, binary zeotropic mixture, constrained multi-objective optimization, energy efficiency, exergy efficiency, Kalina cycle

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2512 ICT for Smart Appliances: Current Technology and Identification of Future ICT Trend

Authors: Abubakar Uba Ibrahim, Ibrahim Haruna Shanono

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Smart metering and demand response are gaining ground in industrial and residential applications. Smart Appliances have been given concern towards achieving Smart home. The success of Smart grid development relies on the successful implementation of Information and Communication Technology (ICT) in power sector. Smart Appliances have been the technology under development and many new contributions to its realization have been reported in the last few years. The role of ICT here is to capture data in real time, thereby allowing bi-directional flow of information/data between producing and utilization point; that lead a way for the attainment of Smart appliances where home appliances can communicate between themselves and provide a self-control (switch on and off) using the signal (information) obtained from the grid. This paper depicts the background on ICT for smart appliances paying a particular attention to the current technology and identifying the future ICT trends for load monitoring through which smart appliances can be achieved to facilitate an efficient smart home system which promote demand response program. This paper grouped and reviewed the recent contributions, in order to establish the current state of the art and trends of the technology, so that the reader can be provided with a comprehensive and insightful review of where ICT for smart appliances stands and is heading to. The paper also presents a brief overview of communication types, and then narrowed the discussion to the load monitoring (Non-intrusive Appliances Load Monitoring ‘NALM’). Finally, some future trends and challenges in the further development of the ICT framework are discussed to motivate future contributions that address open problems and explore new possibilities.

Keywords: communication technology between appliances, demand response, load monitoring, smart appliances, smart grid

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2511 From Knives to Kites: Developments and Dilemmas around the Use of Force in the Israeli–Palestinian Conflict since "Protective Edge"

Authors: Hilly Moodrick-Even Khen

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This study analyzes the legal regulation of the use of force in international law in the context of three emerging Palestinian forms of struggle against Israeli occupation: the Knife Intifada, Gaza border disturbances, and the launching of incendiary kites. It discusses what legal paradigms or concepts should regulate the type and level of force used in each situation—a question that is complicated by various dilemmas—and appraises the Israel Defence Forces policies tailored in response. Methodologically, the study is based on analysis of scholarship on the conceptual legal issues as well as dicta of the courts. It evaluates the applicability of two legal paradigms regulating the use of force in military operations—(i) the conduct of hostilities and (ii) law enforcement—as well as the concept of self-defense in international law and the escalation of force procedure. While the “Knife Intifada” clearly falls under the law enforcement paradigm, the disturbances at the border and the launching of incendiary kites raise more difficult questions, as applying law enforcement, especially in the latter case, can have undesirable ramifications for safeguarding humanitarian interests. The use of force in the cases of the border disturbances and the incendiary kites should thus be regulated, mutatis mutandis, by the concept of self-defense and escalation of force procedures; and in the latter case, the hostilities paradigm can also be applied. The study provides a factual description and analysis of the background and nature of the forms of struggle in Gaza and the West Bank—in each case surveying the geo-political developments since operation Protective Edge, contextualizing how the organized and unorganized violent activities evolved, and analyzing them in terms of level of organization and intensity. It then presents the two paradigms of the use of force—law enforcement and conduct of hostilities—and the concept of self-defense. Lastly, it uses the factual findings as the basis for legally analyzing which paradigm or concept regulating the use of force applies for each form of struggle. The study concludes that in most cases, the concept of self-defense is preferable to the hostilities or the law enforcement paradigms, as it best safeguards humanitarian interests and ensures the least loss of civilian lives.

Keywords: Israeli-Palestinian conflict, self defense, terrorism, use of force

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2510 Writing Hybridized Narratives to Enact Scientific Literacy and the Myth of the Scientific Method

Authors: Ajaz Shaheen, Jawaid Ahmed Siddqui

Abstract:

This world has purely become scientific and technological, and therefore it demands more from our young learners to be more intellectual in learning sciences. A point of concern that is dragging the attention of educationists is that young learners are gradually detaching from science and scientific theory. To deal with this matter, we must arrange such engaging activities that may improve the imaginative skills of our young learners. Our ongoing research program highlights the effects of such activities that demand the learners to interpret scientific information in the form of text they possess. These mixed stories are also known as what we call BioStories. Learners upload their narratives on different websites to let their peers go through their manuscripts. That, as a result, brings more refinement to their works. Moreover, stories allow the learners to read, understand and learn on a broader spectrum. We have conducted separate studies with learners from Grades 6, 9, and 12 that involve case studies and quasi-experimental designs. The conclusion we drew from the analysis of Grade 6 learners was that the alignment of stories helped them become more familiar with the scientific issue. Not only this but also the learners of the respective grade built up their interest in the subject and also developed a clear understanding of related subject topics. On the other hand, results from the 8th and 9th grades study support the argument that learners reflected a positive attitude toward writing scientific information. Lastly, we concluded from the 12th-grade learners that they took pride in their writing skills and built up their strength, determination, and interest. The students became self-conscious as they wrote hybridized scientific narratives in science.

Keywords: BioStories, hybridized writing, scientific literacy, scientific method

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2509 Analysis of Developments in the Understanding of In-Service Training in Turkish Public Administration: Personnel Management to Human Resource Management

Authors: Sema Müge Özdemiray

Abstract:

In line with the new public management approach to provide effective and efficient services necessary to achieve the social goals of public institutions, employees must have the knowledge and skills required by the age. In conjunction with the transition from personnel management to human resources management, it is seen that there is a change in the understanding of in-service training, the understanding of "required in-service training" has switched to the understanding of "continuous in-service training". However, in terms of in-service training in Turkey, it seems to be trouble at the point of adopting to change. The main purpose of this study is to primarily create a conceptual framework of in-service training and subsequently determine, analyze and discuss the developments and problems faced by in-service training in Turkey in the transition from personnel management to human resources management. In accordance with this purpose, the necessary data of this study were collected using qualitative approaches. Observation and document analysis was used and content analysis was performed on the data gathered in the study. The results of this study, according to data such as the number of institutions requesting in-service training, allocated budget of in-service training, the number of people participating in such training, transition of personnel management to human resources management should not lead to a paradigm shift in Turkey’s understanding of in-service training, although this is compulsory for public institutions in accordance with the law in Turkey. In-service training in Turkish public administration is still not implemented effectively and is seen as a social activity for employees and a formality for institutions.

Keywords: Human resources management, in service training, personnel management, public institutions

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2508 Implementation of Lean Production in Business Enterprises: A Literature-Based Content Analysis of Implementation Procedures

Authors: P. Pötters, A. Marquet, B. Leyendecker

Abstract:

The objective of this paper is to investigate different implementation approaches for the implementation of Lean production in companies. Furthermore, a structured overview of those different approaches is to be made. Therefore, the present work is intended to answer the following research question: What differences and similarities exist between the various systematic approaches and phase models for the implementation of Lean Production? To present various approaches for the implementation of Lean Production discussed in the literature, a qualitative content analysis was conducted. Within the framework of a qualitative survey, a selection of texts dealing with lean production and its introduction was examined. The analysis presents different implementation approaches from the literature, covering the descriptive aspect of the study. The study also provides insights into similarities and differences among the implementation approaches, which are drawn from the analysis of latent text contents and author interpretations. In this study, the focus is on identifying differences and similarities among systemic approaches for implementing Lean Production. The research question takes into account the main object of consideration, objectives pursued, starting point, procedure, and endpoint of the implementation approach. The study defines the concept of Lean Production and presents various approaches described in literature that companies can use to implement Lean Production successfully. The study distinguishes between five systemic implementation approaches and seven phase models to help companies choose the most suitable approach for their implementation project. The findings of this study can contribute to enhancing transparency regarding the existing approaches for implementing Lean Production. This can enable companies to compare and contrast the available implementation approaches and choose the most suitable one for their specific project.

Keywords: implementation, lean production, phase models, systematic approaches

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2507 Igbo Art: A Reflection of the Igbo’s Visual Culture

Authors: David Osa-Egonwa

Abstract:

Visual culture is the expression of the norms and social behavior of a society in visual images. A reflection simply shows you how you look when you stand before a mirror, a clear water or stream. The mirror does not alter, improve or distort your original appearance, neither does it show you a caricature of what stands before it, this is the case with visual images created by a tribe or society. The ‘uli’ is hand drawn body design done on Igbo women and speaks of a culture of body adornment which is a practice that is appreciated by that tribe. The use of pattern of the gliding python snake ‘ije eke’ or ‘ijeagwo’ for wall painting speaks of the Igbo culture as one that appreciates wall paintings based on these patterns. Modern life came and brought a lot of change to the Igbo-speaking people of Nigeria. Change cloaked in the garment of Westernization has influenced the culture of the Igbos. This has resulted in a problem which is a break in the cultural practice that has also affected art produced by the Igbos. Before the colonial masters arrived and changed the established culture practiced by the Igbos, visual images were created that retained the culture of this people. To bring this point to limelight, this paper has adopted a historical method. A large number of works produced during pre and post-colonial era which range from sculptural pieces, paintings and other artifacts, just to mention a few, were studied carefully and it was discovered that the visual images hold the culture or aspects of the culture of the Igbos in their renditions and can rightly serve as a mirror of the Igbo visual culture.

Keywords: artistic renditions, historical method, Igbo visual culture, changes

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2506 Identification and Classification of Entrepreneurial Opportunities in Blinds’ Tourism Industry in Khuzestan Province of Iran

Authors: Ali Kharazi, Hassanali Aghajani, Hesami Azizi

Abstract:

Tourism entrepreneurship is a growing field that has the potential to create new opportunities for sustainable development. The purpose of this study is to identify and classify the entrepreneurial opportunities in the blind tourism industry in Khuzestan Province of Iran that can be created through the operation of blinds’ tours. This study used a mixed methods approach. The qualitative data was collected through semi-structured interviews with 15 tourist guides and tourism activists, while the quantitative data was collected through a questionnaire survey of 40 blind people who had participated in blinds’ tours. The findings of this study suggest that there are a number of entrepreneurial opportunities in the blind tourism industry in Khuzestan Province, including (1) developing and providing accessible tourism services, such as tours, accommodations, restaurants, and transportation, (2) creating and marketing blind-friendly tourism products and experiences (3) training and educating tourism professionals on how to provide accessible and inclusive tourism services. This study contributes to the theoretical understanding of tourism entrepreneurship by providing insights into the entrepreneurial opportunities in the blind tourism industry. The findings of this study can be used to develop policies and programs that support the development of the blind tourism industry. The qualitative data were analyzed using content analysis. The quantitative data were analyzed using descriptive statistics and inferential statistics. This study examines the entrepreneurial opportunities within the blind tourism industry in Khuzestan Province, Iran. In addition, Khuzestan province has made relatively good development in the field of blinds’ tourism. Blind tourists have become loyal customers of blinds’ tours, which has increased their self-confidence and social participation. Tourist guides and centers of tourism services are interested in participating in blinds’ tours more than before, and even other parts outside the tourism field have encouraged sponsorship. Education had a great impact on the quality of tourism services, especially for the blind. It has played a significant role in improving the quality of tourism services for the blind. However, the quality and quantity of infrastructure should be increased in different sectors of tourism services to foster future growth. These opportunities can be used to create new businesses and jobs and to promote sustainable development in the region.

Keywords: entrepreneurship, tourism, blind, sustainable development, Khuzestan

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2505 Assessment of Knowledge and Attitude towards End of Life Care among Nurses Working in Tertiary Hospital

Authors: Emni Omar Daw Hussin, Pathmawathi Subramanian, Wong Li Ping

Abstract:

Background: To provide quality care at the end of life, nurses should possess knowledge and skills to provide effective end-of-life care, as well as develop the attitudes and interpersonal competence to provide compassionate care. Aim: This study aimed to assess nurses’ knowledge and attitude towards end of life care and caring for terminal ill patients and to examine relationships among demographic variables and nurse’s knowledge and attitudes toward end of life care and caring for terminal ill patients. Method: a cross-sectional study was conducted at 1 tertiary hospital located in Kuala Lumpur, Malaysia. Self-administrative questionnaire was used to collect data from 553 nurses from over all departments except emergency department, operation theater and outpatient clinic. Two tools were used in this study, the Frommelt’s Attitude Toward Care of the Dying (FATCOD) Scale to assess the nurses’ attitude and End of Life Knowledge Assessment to assess the nurses’ knowledge. Result: the result of this study yielded that, the majority of participants (54.8%) and (54.4%) have less positive attitude and knowledge towards end of life care and caring for terminal ill patients respectively. As well as there is no significant relationship were found between nurses’ ethnicity, religion, and the total score of FATCOD scale; End of Life Knowledge Assessment score. On other hand there is significant relationship among nurses’ age, working experience, level of education, attending any post basic courses and the total score of both FATCOD scale and End of Life Knowledge Assessment. Conclusion: A lack of education and experience and post basic course about end of life care and palliative care may contribute to the negative attitudes and poor knowledge regarding end of life care. Providing sufficient courses about end of life care could enhance the nurses’ knowledge towards end of life care, as well as providing a reflective narrative environment in which nurses can express their personal feelings about death and dying could be a potentially effective approach. Implication for Practice: This study elaborates the need for further research to develop an effective educational programs to enhance nurses’ knowledge and to promote positive attitude towards death and dying, as well as enhance communication skills, and coping strategies.

Keywords: knowledge, attitude, nurse, end of life care

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2504 Surface Roughness Prediction Using Numerical Scheme and Adaptive Control

Authors: Michael K.O. Ayomoh, Khaled A. Abou-El-Hossein., Sameh F.M. Ghobashy

Abstract:

This paper proposes a numerical modelling scheme for surface roughness prediction. The approach is premised on the use of 3D difference analysis method enhanced with the use of feedback control loop where a set of adaptive weights are generated. The surface roughness values utilized in this paper were adapted from [1]. Their experiments were carried out using S55C high carbon steel. A comparison was further carried out between the proposed technique and those utilized in [1]. The experimental design has three cutting parameters namely: depth of cut, feed rate and cutting speed with twenty-seven experimental sample-space. The simulation trials conducted using Matlab software is of two sub-classes namely: prediction of the surface roughness readings for the non-boundary cutting combinations (NBCC) with the aid of the known surface roughness readings of the boundary cutting combinations (BCC). The following simulation involved the use of the predicted outputs from the NBCC to recover the surface roughness readings for the boundary cutting combinations (BCC). The simulation trial for the NBCC attained a state of total stability in the 7th iteration i.e. a point where the actual and desired roughness readings are equal such that error is minimized to zero by using a set of dynamic weights generated in every following simulation trial. A comparative study among the three methods showed that the proposed difference analysis technique with adaptive weight from feedback control, produced a much accurate output as against the abductive and regression analysis techniques presented in this.

Keywords: Difference Analysis, Surface Roughness; Mesh- Analysis, Feedback control, Adaptive weight, Boundary Element

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2503 Effect of Friction Pressure on the Properties of Friction Welded Aluminum–Ceramic Dissimilar Joints

Authors: Fares Khalfallah, Zakaria Boumerzoug, Selvarajan Rajakumar, Elhadj Raouache

Abstract:

The ceramic-aluminum bond is strongly present in industrial tools, due to the need to combine the properties of metals, such as ductility, thermal and electrical conductivity, with ceramic properties like high hardness, corrosion and wear resistance. In recent years, some joining techniques have been developed to achieve a good bonding between these materials such as brazing, diffusion bonding, ultrasonic joining and friction welding. In this work, AA1100 aluminum alloy rods were welded with Alumina 99.9 wt% ceramic rods, by friction welding. The effect of friction pressure on mechanical and structural properties of welded joints was studied. The welding was performed by direct friction welding machine. The welding samples were rotated at a constant rotational speed of 900 rpm, friction time of 4 sec, forging strength of 18 MPa, and forging time of 3 sec. Three different friction pressures were applied to 20, 34 and 45 MPa. The three-point bending test and Vickers microhardness measurements were used to evaluate the strength of the joints and investigate the mechanical properties of the welding area. The microstructure of joints was examined by optical microscopy (OM), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results show that bending strength increased, and then decreased after reaching a maximum value, with increasing friction pressure. The SEM observation shows that the increase in friction pressure led to the appearance of cracks in the microstructure of the interface area, which is decreasing the bending strength of joints.

Keywords: welding of ceramic to aluminum, friction welding, alumina, AA1100 aluminum alloy

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2502 A Closed Loop Audit of Pre-operative Transfusion Samples in Orthopaedic Patients at a Major Trauma Centre

Authors: Tony Feng, Rea Thomson, Kathryn Greenslade, Ross Medine, Jennifer Easterbrook, Calum Arthur, Matilda Powell-bowns

Abstract:

There are clear guidelines on taking group and screen samples (G&S) for elective arthroplasty and major trauma. However, there is limited guidance on blood grouping for other trauma patients. The purpose of this study was to review the level of blood grouping at a major trauma centre and validate a protocol that limits the expensive processing of G&S samples. After reviewing the national guidance on transfusion samples in orthopaedic patients, data was prospectively collected for all orthopaedic admissions in the Royal Infirmary of Edinburgh between January to February 2023. The cause of admission, number of G&S samples processed on arrival and need for red cells was collected using the hospital blood bank. A new protocol was devised based on a multidisciplinary meeting which limited the requirement for G&S samples only to presentations in “category X”, including neck-of-femur fractures (NOFs), pelvic fractures and major trauma. A re-audit was completed between April and May after departmental education and institution of this protocol. 759 patients were admitted under orthopaedics in the major trauma centre across two separate months. 47% of patients were admitted with presentations falling in category X (354/759) and patients in this category accounted for 88% (92/104) of those requiring post-operative red cell transfusions. Of these, 51% were attributed to NOFs (47/92). In the initial audit, 50% of trauma patients outwith category X had samples sent (116/230), estimated to cost £3800. Of these 230 patients, 3% required post-operative transfusions (7/230). In the re-audit, 23% of patients outwith category X had samples sent (40/173), estimated to cost £1400, of which 3% (5/173) required transfusions. None of the transfusions in these patients in either audit were related to their operation and the protocol achieved an estimated cost saving of £2400 over one month. This study highlights the importance of sending samples for patients with certain categories of orthopaedic trauma (category X) due to the high demand for post-operative transfusions. However, the absence of transfusion requirements in other presentations suggests over-testing. While implementation of the new protocol has markedly reduced over-testing, additional interventions are required to reduce this further.

Keywords: blood transfusion, quality improvement, orthopaedics, trauma

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2501 DNA as an Instrument in Constructing Narratives and Justice in Criminal Investigations: A Socio-Epistemological Exploration

Authors: Aadita Chaudhury

Abstract:

Since at least the early 2000s, DNA profiling has achieved a preeminent status in forensic investigations into criminal acts. While the criminal justice system has a long history of using forensic evidence and testing them through establish technoscientific means, the primacy of DNA in establishing 'truth' or reconstructing a series of events is unparalleled in the history of forensic science. This paper seeks to elucidate the ways in which DNA profiling has become the most authoritative instrument of 'truth' in criminal investigations, and how it is used in the legal process to ascertain culpability, create the notion of infallible evidence, and advance the search for justice. It is argued that DNA profiling has created a paradigm shift in how the legal system and the general public understands crime and culpability, but not without limitations. There are indications that even trace amounts of DNA evidence can point to causal links in a criminal investigation, however, there still remains many rooms to create confusion and doubt from empirical evidence within the narrative of crimes. Many of the shortcomings of DNA-based forensic investigations are explored and evaluated with regards to claims of the authority of biological evidence and implications for the public understanding of the elusive concepts of truth and justice in the present era. Public misinformation about the forensic analysis processes could produce doubt or faith in the judgements rooted in them, depending on other variables presented at the trial. A positivist understanding of forensic science that is shared by the majority of the population does not take into consideration that DNA evidence is far from definitive, and can be used to support any theories of culpability, to create doubt and to deflect blame.

Keywords: DNA profiling, epistemology of forensic science, philosophy of forensic science, sociology of scientific knowledge

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2500 Impact and Risk Assessment of Climate Change on Water Quality: A Study in the Errer River Basin, Taiwan

Authors: Hsin-Chih Lai, Yung-Lung Lee, Yun-Yao Chi, Ching-Yi Horng, Pei-Chih Wu, Hsien-Chang Wang

Abstract:

Taiwan, a climatically challenged island, has always been keen on the issue of water resource management due to its limitations in water storage. Since water resource management has been the focal point of many adaptations to climate change, there has been a lack of attention on another issue, water quality. This study chooses the Errer River Basin as the experimental focus for water quality in Taiwan. With the Errer River Basin being one of the most polluted rivers in Taiwan, this study observes the effects of climate change on this river over a period of time. Taiwan is also targeted by multiple typhoons every year, the heavy rainfall and strong winds create problems of pollution being carried to different river segments, including into the ocean. This study aims to create an impact and risk assessment on Errer River Basin, to show the connection from climate change to potential extreme events, which in turn could influence water quality and ultimately human health. Using dynamic downscaling, this study narrows the information from a global scale to a resolution of 1 km x 1 km. Then, through interpolation, the resolution is further narrowed into a resolution of 200m x 200m, to analyze the past, present, and future of extreme events. According to different climate change scenarios, this study designs an assessment index on the vulnerability of the Errer River Basin. Through this index, Errer River inhabitants can access advice on adaptations to climate change and act accordingly.

Keywords: climate change, adaptation, water quality, risk assessment

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2499 Selective Oxidation of 6Mn-2Si Advanced High Strength Steels during Intercritical Annealing Treatment

Authors: Maedeh Pourmajidian, Joseph R. McDermid

Abstract:

Advanced High Strength Steels are revolutionizing both the steel and automotive industries due to their high specific strength and ability to absorb energy during crash events. This allows manufacturers to design vehicles with significantly increased fuel efficiency without compromising passenger safety. To maintain the structural integrity of the fabricated parts, they must be protected from corrosion damage through continuous hot-dip galvanizing process, which is challenging due to selective oxidation of Mn and Si on the surface of this AHSSs. The effects of process atmosphere oxygen partial pressure and small additions of Sn on the selective oxidation of a medium-Mn C-6Mn-2Si advanced high strength steel was investigated. Intercritical annealing heat treatments were carried out at 690˚C in an N2-5%H2 process atmosphere under dew points ranging from –50˚C to +5˚C. Surface oxide chemistries, morphologies, and thicknesses were determined at a variety of length scales by several techniques, including SEM, TEM+EELS, and XPS. TEM observations of the sample cross-sections revealed the transition to internal oxidation at the +5˚C dew point. EELS results suggested that the internal oxides network was composed of a multi-layer oxide structure with varying chemistry from oxide core towards the outer part. The combined effect of employing a known surface active element as a function of process atmosphere on the surface structure development and the possible impact on reactive wetting of the steel substrates by the continuous galvanizing zinc bath will be discussed.

Keywords: 3G AHSS, hot-dip galvanizing, oxygen partial pressure, selective oxidation

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