Search results for: path independence number
Commenced in January 2007
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Paper Count: 11532

Search results for: path independence number

1692 Iterative Reconstruction Techniques as a Dose Reduction Tool in Pediatric Computed Tomography Imaging: A Phantom Study

Authors: Ajit Brindhaban

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Background and Purpose: Computed Tomography (CT) scans have become the largest source of radiation in radiological imaging. The purpose of this study was to compare the quality of pediatric Computed Tomography (CT) images reconstructed using Filtered Back Projection (FBP) with images reconstructed using different strengths of Iterative Reconstruction (IR) technique, and to perform a feasibility study to assess the use of IR techniques as a dose reduction tool. Materials and Methods: An anthropomorphic phantom representing a 5-year old child was scanned, in two stages, using a Siemens Somatom CT unit. In stage one, scans of the head, chest and abdomen were performed using standard protocols recommended by the scanner manufacturer. Images were reconstructed using FBP and 5 different strengths of IR. Contrast-to-Noise Ratios (CNR) were calculated from average CT number and its standard deviation measured in regions of interest created in the lungs, bone, and soft tissues regions of the phantom. Paired t-test and the one-way ANOVA were used to compare the CNR from FBP images with IR images, at p = 0.05 level. The lowest strength value of IR that produced the highest CNR was identified. In the second stage, scans of the head was performed with decreased mA(s) values relative to the increase in CNR compared to the standard FBP protocol. CNR values were compared in this stage using Paired t-test at p = 0.05 level. Results: Images reconstructed using IR technique had higher CNR values (p < 0.01.) in all regions compared to the FBP images, at all strengths of IR. The CNR increased with increasing IR strength of up to 3, in the head and chest images. Increases beyond this strength were insignificant. In abdomen images, CNR continued to increase up to strength 5. The results also indicated that, IR techniques improve CNR by a up to factor of 1.5. Based on the CNR values at strength 3 of IR images and CNR values of FBP images, a reduction in mA(s) of about 20% was identified. The images of the head acquired at 20% reduced mA(s) and reconstructed using IR at strength 3, had similar CNR as FBP images at standard mA(s). In the head scans of the phantom used in this study, it was demonstrated that similar CNR can be achieved even when the mA(s) is reduced by about 20% if IR technique with strength of 3 is used for reconstruction. Conclusions: The IR technique produced better image quality at all strengths of IR in comparison to FBP. IR technique can provide approximately 20% dose reduction in pediatric head CT while maintaining the same image quality as FBP technique.

Keywords: filtered back projection, image quality, iterative reconstruction, pediatric computed tomography imaging

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1691 Antioxidative, Anticholinesterase and Anti-Neuroinflammatory Properties of Malaysian Brown and Green Seaweeds

Authors: Siti Aisya Gany, Swee Ching Tan, Sook Yee Gan

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Diminished antioxidant defense or increased production of reactive oxygen species in the biological system can result in oxidative stress which may lead to various neurodegenerative diseases including Alzheimer’s disease (AD). Microglial activation also contributes to the progression of AD by producing several pro-inflammatory cytokines, nitric oxide (NO), and prostaglandin E2 (PGE2). Oxidative stress and inflammation have been reported to be possible pathophysiological mechanisms underlying AD. In addition, the cholinergic hypothesis postulates that memory impairment in patient with AD is also associated with the deficit of cholinergic function in the brain. Although a number of drugs have been approved for the treatment of AD, most of these synthetic drugs have diverse side effects and yield relatively modest benefits. Marine algae have great potential in pharmaceutical and biomedical applications as they are valuable sources of bioactive properties such as anti-coagulation, anti-microbial, anti-oxidative, anti-cancer and anti-inflammatory. Hence, this study aimed to provide an overview of the properties of Malaysian seaweeds (Padina australis, Sargassum polycystum and Caulerpa racemosa) in inhibiting oxidative stress, neuroinflammation and cholinesterase enzymes. All tested samples significantly exhibit potent DPPH and moderate Superoxide anion radical scavenging ability (P<0.05). Hexane and methanol extracts of S. polycystum exhibited the most potent radical scavenging ability with IC50 values of 0.1572 ± 0.004 mg/ml and 0.8493 ± 0.02 for DPPH and ABTS assays, respectively. Hexane extract of C. racemosa gave the strongest superoxide radical inhibitory effect (IC50 of 0.3862± 0.01 mg/ml). Most seaweed extracts significantly inhibited the production of cytokine (IL-6, IL-1 β, TNFα) and NO in a concentration-dependent manner without causing significant cytotoxicity to the lipopolysaccharide (LPS)-stimulated microglia cells (P<0.05). All extracts suppressed cytokine and NO level by more than 80% at the concentration of 0.4mg/ml. In addition, C. racemosa and S. polycystum also showed anti-acetylcholinesterase activities with the IC50 values ranging from 0.086-0.115 mg/ml. Moreover, C. racemosa and P. australis were also found to be active against butyrylcholinesterase with IC50 values ranging from 0.118-0.287 mg/ml.

Keywords: anti-cholinesterase, anti-oxidative, neuroinflammation, seaweeds

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1690 In-situ and Laboratory Characterization of Fiji Lateritic Soils

Authors: Faijal Ali, Darga Kumar N., Ravikant Singh, Rajnil Lal

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Fiji has three major landforms such as plains, low mountains, and hills. The low land soils are formed on beach sand. Fiji soils contain high concentration of iron (III), aluminum oxides and hydroxides. The soil possesses reddish or yellowish colour. The characterization of lateritic soils collected from different locations along the national highway in Viti Levu, Fiji Islands. The research has been carried out mainly to understand the physical and strength properties to assess their suitability for the highway and building construction. In this paper, the field tests such as dynamic cone penetrometer test, field vane shear, field density and laboratory tests such as unconfined compression stress, compaction, grain size analysis and Atterberg limits are conducted. The test results are analyzed and presented. From the results, it is revealed that the soils are having more percentage of silt and clay which is more than 80% and 5 to 15% of fine to medium sand is noticed. The dynamic cone penetrometer results up to 3m depth had similar penetration resistance. For the first 1m depth, the rate of penetration is found 300mm per 3 to 4 blows. In all the sites it is further noticed that the rate of penetration at depths beyond 1.5 m is decreasing for the same number of blows as compared to the top soil. From the penetration resistance measured through dynamic cone penetrometer test, the California bearing ratio and allowable bearing capacities are 4 to 5% and 50 to 100 kPa for the top 1m layer and below 1m these values are increasing. The California bearing ratio of these soils for below 1m depth is in the order of 10% to 20%. The safe bearing capacity of these soils below 1m and up to 3m depth is varying from 150 kPa to 250 kPa. The field vane shear was measured within a depth of 1m from the surface and the values were almost similar varying from 60 kPa to 120 kPa. The liquid limit and plastic limits of these soils are in the range of 40 to 60% and 20 to 25%. Overall it is found that the top 1m soil along the national highway in majority places possess a soft to medium stiff behavior with low to medium bearing capacity as well low California bearing ratio values. It is recommended to ascertain these soils behavior in terms of geotechnical parameters before taking up any construction activity.

Keywords: California bearing ratio, dynamic cone penetrometer test, field vane shear, unconfined compression stress.

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1689 The School Governing Council as the Impetus for Collaborative Education Governance: A Case Study of Two Benguet Municipalities in the Highlands of Northern Philippines

Authors: Maria Consuelo Doble

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For decades, basic public education in the Philippines has been beleaguered by a governance scenario of multi-layered decision-making and the lack of collaboration between sectors in addressing issues on poor access to schools, high dropout rates, low survival rates, and poor student performance. These chronic problems persisted despite multiple efforts making it appear that the education system is incapable of reforming itself. In the mountainous rural towns of La Trinidad and Tuba, in the province of Benguet in Northern Philippines, collaborative education governance was catalyzed by the intervention of Synergeia Foundation, a coalition made up of individuals, institutions and organizations that aim to improve the quality of education in the Philippines. Its major thrust is to empower the major stakeholders at the community level to make education work by building the capacities of School Governing Councils (SGCs). Although mandated by the Department of Education in 2006, the SGCs in Philippine public elementary schools remained dysfunctional. After one year of capacity-building by Synergeia Foundation, some SGCs are already exhibiting active community-based multi-sectoral collaboration, while there are many that are not. With the myriad of factors hindering collaboration, Synergeia Foundation is now confronted with the pressing question: What are the factors that promote collaborative governance in the SGCs so that they can address the education-related issues that they are facing? Using Emerson’s (2011) framework on collaborative governance, this study analyzes the application of collaborative governance by highly-functioning SGCs in the public elementary schools of Tuba and La Trinidad. Findings of this action research indicate how the dynamics of collaboration composed of three interactive and iterative components – principled engagement, shared motivation and capacity for joint action – have resulted in meaningful short-term impact such as stakeholder engagement and decreased a number of dropouts. The change in the behavior of stakeholders is indicative of adaptation to a more collaborative approach in governing education in Benguet highland settings such as Tuba and La Trinidad.

Keywords: basic public education, Benguet highlands, collaborative governance, School Governing Council

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1688 Going beyond Elementary Algebraic Identities: The Expectation of a Gifted Child, an Indian Scenario

Authors: S. R. Santhanam

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A gifted child is one who gives evidence of creativity, good memory, rapid learning. In mathematics, a teacher often comes across some gifted children and they exhibit the following characteristics: unusual alertness, enjoying solving problems, getting bored on repetitions, self-taught, going beyond what teacher taught, ask probing questions, connecting unconnected concepts, vivid imagination, readiness for research work, perseverance of a topic. There are two main areas of research carried out on them: 1)identifying gifted children, 2) interacting and channelizing them. A lack of appropriate recognition will lead the gifted child demotivated. One of the main findings is if proper attention and nourishment are not given then it leads a gifted child to become depressed, underachieving, fail to reach their full potential and sometimes develop negative attitude towards school and study. After identifying them, a mathematics teacher has to develop them into a fall fledged achiever. The responsibility of the teacher is enormous. The teacher has to be resourceful and patient. But interacting with them one finds a lot of surprises and awesomeness. The elementary algebraic identities like (a+b)(a-b)=a²-b², expansion of like (a+b)²(a-b)² and others are taught to students, of age group 13-15 in India. An average child will be satisfied with a single proof and immediate application of these identities. But a gifted child expects more from the teacher and at one stage after a little training will surpass the teacher also. In this short paper, the author shares his experience regarding teaching algebraic identities to gifted children. The following problem was given to a set of 10 gifted children of the specified age group: If a natural number ‘n’ to expressed as the sum of the two squares, will 2n also be expressed as the sum of two squares? An investigation has been done on what multiples of n satisfying the criterion. The attempts of the gifted children were consolidated and conclusion was drawn. A second problem was given to them as: can two natural numbers be found such that the difference of their square is 3? After a successful solution, more situations were analysed. As a third question, the finding of the sign of an algebraic expression in three variables was analysed. As an example: if a,b,c are real and unequal what will be sign of a²+4b²+9c²-4ab-12bc-6ca? Apart from an expression as a perfect square what other methods can be employed to prove an algebraic expression as positive negative or non negative has been analysed. Expressions like 4x²+2y²+13y²-2xy-4yz-6zx were given, and the children were asked to find the sign of the expression for all real values of x,y and z. In all investigations, only basic algebraic identities were used. As a next probe, a divisibility problem was initiated. When a,b,c are natural numbers such that a+b+c is at least 6, and if a+b+c is divisible by 6 then will 6 divide a³+b³+c³. The gifted children solved it in two different ways.

Keywords: algebraic identities, gifted children, Indian scenario, research

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1687 Academic Identities in Transition

Authors: Caroline Selai, Sushrut Jadhav

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Background: University College London (UCL), the first secular university in England to admit students regardless of their religion and gender, has nearly 29,000 students of which approximately 30% are international students. The UCL Cultural Consultation Service (CCS) for staff and students is a unique service that provides assistance to staff and students experiencing challenges in their teaching, enabling, support work or studies which they believe may have a cultural component. The service provides one-to-one and group consultations, lectures, seminars, ‘grand rounds’, interactive workshops and bespoke interventions. Data: This paper presents a content analysis of CCS referrals over the last 36 months. We focus on the experience of international students, many of whom experience not only a challenge to their academic identity but also a profound challenge to their personal cultural identity. We also present 3 vignettes to illustrate how students interpret, accept, contest and resist changes in their cultural and academic identity. Discussion: This paper highlights (i) how students from collectivist cultures attempt to assimilate within an individualistic, highly competitive western university that is bound by its own institutional norms; (ii) problems in negotiating challenges at the interface of culture and gender (iii) the impact of culturally different hierarchies of power, discrimination and authority and (iv) the significance of earlier traumatic and kinship conflicts. Many international students’ social identities are shaped by their cultural and family scripts. A large number have been taught that their teachers are to be revered and their teachings unchallenged. This is at odds with quintessential goal of the western university to encourage healthy scepticism and hone students’ critical thinking skills. Conclusions: Pupil-teacher ‘cultural transference’ and shifts in cultural academic identities of students underscore critical aspects of developmental and learning challenges for students. Staff-student cultural conflict requires a broader, systemic analysis of students, staff and the wider organisation. Our findings challenge Eurocentric psychodynamic concepts such as the nature of parent-child relationship in Western Europe. We argue for a broader, more inclusive approach to develop both effective pedagogic skills in euro-american academic institutions and culturally- appropriate psychodynamic theory to underpin counselling international students.

Keywords: academic identity, cultural transference, cultural consultation in higher education, cultural formulation, cultural identity.

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1686 Estimation of Noise Barriers for Arterial Roads of Delhi

Authors: Sourabh Jain, Parul Madan

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Traffic noise pollution has become a challenging problem for all metro cities of India due to rapid urbanization, growing population and rising number of vehicles and transport development. In Delhi the prime source of noise pollution is vehicular traffic. In Delhi it is found that the ambient noise level (Leq) is exceeding the standard permissible value at all the locations. Noise barriers or enclosures are definitely useful in obtaining effective deduction of traffic noise disturbances in urbanized areas. US’s Federal Highway Administration Model (FHWA) and Calculation of Road Traffic Noise (CORTN) of UK are used to develop spread sheets for noise prediction. Spread sheets are also developed for evaluating effectiveness of existing boundary walls abutting houses in mitigating noise, redesigning them as noise barriers. Study was also carried out to examine the changes in noise level due to designed noise barrier by using both models FHWA and CORTN respectively. During the collection of various data it is found that receivers are located far away from road at Rithala and Moolchand sites and hence extra barrier height needed to meet prescribed limits was less as seen from calculations and most of the noise diminishes by propagation effect.On the basis of overall study and data analysis, it is concluded that FHWA and CORTN models under estimate noise levels. FHWA model predicted noise levels with an average percentage error of -7.33 and CORTN predicted with an average percentage error of -8.5. It was observed that at all sites noise levels at receivers were exceeding the standard limit of 55 dB. It was seen from calculations that existing walls are reducing noise levels. Average noise reduction due to walls at Rithala was 7.41 dB and at Panchsheel was 7.20 dB and lower amount of noise reduction was observed at Friend colony which was only 5.88. It was observed from analysis that Friends colony sites need much greater height of barrier. This was because of residential buildings abutting the road. At friends colony great amount of traffic was observed since it is national highway. At this site diminishing of noise due to propagation effect was very less.As FHWA and CORTN models were developed in excel programme, it eliminates laborious calculations of noise. There was no reflection correction in FHWA models as like in CORTN model.

Keywords: IFHWA, CORTN, Noise Sources, Noise Barriers

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1685 Optimizing Electric Vehicle Charging Networks with Dynamic Pricing and Demand Elasticity

Authors: Chiao-Yi Chen, Dung-Ying Lin

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With the growing awareness of environmental protection and the implementation of government carbon reduction policies, the number of electric vehicles (EVs) has rapidly increased, leading to a surge in charging demand and imposing significant challenges on the existing power grid’s capacity. Traditional urban power grid planning has not adequately accounted for the additional load generated by EV charging, which often strains the infrastructure. This study aims to optimize grid operation and load management by dynamically adjusting EV charging prices based on real-time electricity supply and demand, leveraging consumer demand elasticity to enhance system efficiency. This study uniquely addresses the intricate interplay between urban traffic patterns and power grid dynamics in the context of electric vehicle (EV) adoption. By integrating Hsinchu City's road network with the IEEE 33-bus system, the research creates a comprehensive model that captures both the spatial and temporal aspects of EV charging demand. This approach allows for a nuanced analysis of how traffic flow directly influences the load distribution across the power grid. The strategic placement of charging stations at key nodes within the IEEE 33-bus system, informed by actual road traffic data, enables a realistic simulation of the dynamic relationship between vehicle movement and energy consumption. This integration of transportation and energy systems provides a holistic view of the challenges and opportunities in urban EV infrastructure planning, highlighting the critical need for solutions that can adapt to the ever-changing interplay between traffic patterns and grid capacity. The proposed dynamic pricing strategy effectively reduces peak charging loads, enhances the operational efficiency of charging stations, and maximizes operator profits, all while ensuring grid stability. These findings provide practical insights and a valuable framework for optimizing EV charging infrastructure and policies in future smart cities, contributing to more resilient and sustainable urban energy systems.

Keywords: dynamic pricing, demand elasticity, EV charging, grid load balancing, optimization

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1684 Interplay of Physical Activity, Hypoglycemia, and Psychological Factors: A Longitudinal Analysis in Diabetic Youth

Authors: Georges Jabbour

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Background and aims: This two-year follow-up study explores the long-term sustainability of physical activity (PA) levels in young people with type 1 diabetes, focusing on the relationship between PA, hypoglycemia, and behavioral scores. The literature highlights the importance of PA and its health benefits, as well as the barriers to engaging in PA practices. Studies have shown that individuals with high levels of vigorous physical activity have higher fear of hypoglycemia (FOH) scores and more hypoglycemia episodes. Considering that hypoglycemia episodes are a major barrier to physical activity, and many studies reported a negative association between PA and high FOH scores, it cannot be guaranteed that those experiencing hypoglycemia over a long period will remain active. Building on that, the present work assesses whether high PA levels, despite elevated hypoglycemia risk, can be maintained over time. The study tracks PA levels at one and two years, correlating them with hypoglycemia instances and Fear of Hypoglycemia (FOH) scores. Materials and methods: A self-administered questionnaire was completed by 61 youth with T1D, and their PA was assessed. Hypoglycemia episodes, fear of hypoglycemia scores and HbA1C levels were collected. All assessments were realized at baseline (visit 0: V0), one year (V1) and two years later (V2). For the purpose of the present work, we explore the relationships between PA levels, hypoglycemia episodes, and FOH scores at each time point. We used multiple linear regression to model the mean outcomes for each exposure of interest. Results: Findings indicate no changes in total moderate to vigorous PA (MVPA) and VPA levels among visits, and HbA1c (%) was negatively correlated with the total amount of VPA per day in minutes (β= -0.44; p=0.01, β= -0.37; p=0.04, and β= -0.66; p=0.01 for V0, V1, and V2, respectively). Our linear regression model reported a significant negative correlation between VPA and FOH across the visits (β=-0.59, p=0.01; β= -0.44, p=0.01; and β= -0.34, p=0.03 for V0, V1, and V2, respectively), and HbA1c (%) was influenced by both the number of hypoglycemic episodes and FOH score at V2 (β=0.48; p=0.02 and β=0.38; p=0.03, respectively). Conclusion: The sustainability of PA levels and HbA1c (%) in young individuals with type 1 diabetes is influenced by various factors, including fear of hypoglycemia. Understanding these complex interactions is essential for developing effective interventions to promote sustained PA levels in this population. Our results underline the necessity of a multi-strategic approach to promoting active lifestyles among diabetic youths. This approach should synergize PA enhancement with vigilant glucose monitoring and effective FOH management.

Keywords: physical activity, hypoglycemia, fear of hypoglycemia, youth

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1683 A Method for Evaluating Gender Equity of Cycling from Rawls Justice Perspective

Authors: Zahra Hamidi

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Promoting cycling, as an affordable environmentally friendly mode of transport to replace private car use has been central to sustainable transport policies. Cycling is faster than walking and combined with public transport has the potential to extend the opportunities that people can access. In other words, cycling, besides direct positive health impacts, can improve people mobility and ultimately their quality of life. Transport literature well supports the close relationship between mobility, quality of life, and, well being. At the same time inequity in the distribution of access and mobility has been associated with the key aspects of injustice and social exclusion. The pattern of social exclusion and inequality in access are also often related to population characteristics such as age, gender, income, health, and ethnic background. Therefore, while investing in transport infrastructure it is important to consider the equity of provided access for different population groups. This paper proposes a method to evaluate the equity of cycling in a city from Rawls egalitarian perspective. Since this perspective is concerned with the difference between individuals and social groups, this method combines accessibility measures and Theil index of inequality that allows capturing the inequalities ‘within’ and ‘between’ groups. The paper specifically focuses on two population characteristics as gender and ethnic background. Following Rawls equity principles, this paper measures accessibility by bikes to a selection of urban activities that can be linked to the concept of the social primary goods. Moreover, as growing number of cities around the world have launched bike-sharing systems (BSS) this paper incorporates both private and public bikes networks in the estimation of accessibility levels. Additionally, the typology of bike lanes (separated from or shared with roads), the presence of a bike sharing system in the network, as well as bike facilities (e.g. parking racks) have been included in the developed accessibility measures. Application of this proposed method to a real case study, the city of Malmö, Sweden, shows its effectiveness and efficiency. Although the accessibility levels were estimated only based on gender and ethnic background characteristics of the population, the author suggests that the analysis can be applied to other contexts and further developed using other properties, such as age, income, or health.

Keywords: accessibility, cycling, equity, gender

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1682 An Integrated Approach to Syllabus Design for Business Chinese

Authors: Dongshuo Wang, Minjie Xing

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International businesses prefer to hire people who speak more than one language. With the booming of China’s market, industries and trade, business leaders are looking for people who can speak Chinese and operate successfully in a Chinese cultural context, and therefore an increasing number of tertiary students choose a Business Chinese (BC) course. As a result, BC syllabus design is urgently needed. What business knowledge should be included in China’s context? What aspects of BC culture should be included? How much Chinese language should be introduced to conduct business in China? With these research questions, this research explores a syllabus design that integrates the three aspects of subject knowledge of business in communication, business practice including the procedure of and strategies for communicating business in practice and language skills including the disciplinary and professional contexts in which linguistic choices are made. After literature review and consultancy with China-related business professionals, senior staff from business schools and representatives of students, the authors of this paper, together with language tutors drafted a syllabus based on the integrated approach to include subject knowledge, business practice and language skills. Due to the nature of this research which requires trial/test and detailed description for each correction, qualitative methods are adopted. Two in-depth focus group interviews (with 2 staff and 4 students in each group), and 18 individual interviews (8 staff and 10 students) were conducted. QDA was used for systematizing, organizing, and analysing qualitative data. It was discovered that the business knowledge related to a Chinese cultural context, including face value, networking skills, strategic plans for signing a contract, marketing, sales, and after-sale service, should be introduced through lectures and seminars; business practice could be implemented by students setting up their own companies, virtual or real; and language skills would be trained via writing business messages and presenting their companies in fairs and exhibitions. After a longitudinal study of trials and amendments for three years from 2013 to 2016, the syllabus was approved by staff and students and the university. Students appreciated the syllabus, as they could apply the subject knowledge into practice by using it in their own companies and Chinese language was used throughout the process. The syllabus is now ready to be used in universities offering BC, and the designing process can be applied to other new courses as well.

Keywords: business Chinese, syllabus design, business knowledge, language skills

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1681 Different Stages for the Creation of Electric Arc Plasma through Slow Rate Current Injection to Single Exploding Wire, by Simulation and Experiment

Authors: Ali Kadivar, Kaveh Niayesh

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This work simulates the voltage drop and resistance of the explosion of copper wires of diameters 25, 40, and 100 µm surrounded by 1 bar nitrogen exposed to a 150 A current and before plasma formation. The absorption of electrical energy in an exploding wire is greatly diminished when the plasma is formed. This study shows the importance of considering radiation and heat conductivity in the accuracy of the circuit simulations. The radiation of the dense plasma formed on the wire surface is modeled with the Net Emission Coefficient (NEC) and is mixed with heat conductivity through PLASIMO® software. A time-transient code for analyzing wire explosions driven by a slow current rise rate is developed. It solves a circuit equation coupled with one-dimensional (1D) equations for the copper electrical conductivity as a function of its physical state and Net Emission Coefficient (NEC) radiation. At first, an initial voltage drop over the copper wire, current, and temperature distribution at the time of expansion is derived. The experiments have demonstrated that wires remain rather uniform lengthwise during the explosion and can be simulated utilizing 1D simulations. Data from the first stage are then used as the initial conditions of the second stage, in which a simplified 1D model for high-Mach-number flows is adopted to describe the expansion of the core. The current was carried by the vaporized wire material before it was dispersed in nitrogen by the shock wave. In the third stage, using a three-dimensional model of the test bench, the streamer threshold is estimated. Electrical breakdown voltage is calculated without solving a full-blown plasma model by integrating Townsend growth coefficients (TdGC) along electric field lines. BOLSIG⁺ and LAPLACE databases are used to calculate the TdGC at different mixture ratios of nitrogen/copper vapor. The simulations show both radiation and heat conductivity should be considered for an adequate description of wire resistance, and gaseous discharges start at lower voltages than expected due to ultraviolet radiation and the exploding shocks, which may have ionized the nitrogen.

Keywords: exploding wire, Townsend breakdown mechanism, streamer, metal vapor, shock waves

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1680 Relation Between Traffic Mix and Traffic Accidents in a Mixed Industrial Urban Area

Authors: Michelle Eliane Hernández-García, Angélica Lozano

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The traffic accidents study usually contemplates the relation between factors such as the type of vehicle, its operation, and the road infrastructure. Traffic accidents can be explained by different factors, which have a greater or lower relevance. Two zones are studied, a mixed industrial zone and the extended zone of it. The first zone has mainly residential (57%), and industrial (23%) land uses. Trucks are mainly on the roads where industries are located. Four sensors give information about traffic and speed on the main roads. The extended zone (which includes the first zone) has mainly residential (47%) and mixed residential (43%) land use, and just 3% of industrial use. The traffic mix is composed mainly of non-trucks. 39 traffic and speed sensors are located on main roads. The traffic mix in a mixed land use zone, could be related to traffic accidents. To understand this relation, it is required to identify the elements of the traffic mix which are linked to traffic accidents. Models that attempt to explain what factors are related to traffic accidents have faced multiple methodological problems for obtaining robust databases. Poisson regression models are used to explain the accidents. The objective of the Poisson analysis is to estimate a vector to provide an estimate of the natural logarithm of the mean number of accidents per period; this estimate is achieved by standard maximum likelihood procedures. For the estimation of the relation between traffic accidents and the traffic mix, the database is integrated of eight variables, with 17,520 observations and six vectors. In the model, the dependent variable is the occurrence or non-occurrence of accidents, and the vectors that seek to explain it, correspond to the vehicle classes: C1, C2, C3, C4, C5, and C6, respectively, standing for car, microbus, and van, bus, unitary trucks (2 to 6 axles), articulated trucks (3 to 6 axles) and bi-articulated trucks (5 to 9 axles); in addition, there is a vector for the average speed of the traffic mix. A Poisson model is applied, using a logarithmic link function and a Poisson family. For the first zone, the Poisson model shows a positive relation among traffic accidents and C6, average speed, C3, C2, and C1 (in a decreasing order). The analysis of the coefficient shows a high relation with bi-articulated truck and bus (C6 and the C3), indicating an important participation of freight trucks. For the expanded zone, the Poisson model shows a positive relation among traffic accidents and speed average, biarticulated truck (C6), and microbus and vans (C2). The coefficients obtained in both Poisson models shows a higher relation among freight trucks and traffic accidents in the first industrial zone than in the expanded zone.

Keywords: freight transport, industrial zone, traffic accidents, traffic mix, trucks

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1679 Propagation of Simmondsia chinensis (Link) Schneider by Stem Cuttings

Authors: Ahmed M. Eed, Adam H. Burgoyne

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Jojoba (Simmondsia chinensis (Link) Schneider), is a desert shrub which tolerates saline, alkyle soils and drought. The seeds contain a characteristic liquid wax of economic importance in industry as a machine lubricant and cosmetics. A major problem in seed propagation is that jojoba is a dioecious plant whose sex is not easily determined prior to flowering (3-4 years from germination). To overcome this phenomenon, asexual propagation using vegetative methods such as cutting can be used. This research was conducted to find out the effect of different Plant Growth Regulators (PGRs) and rooting media on Jojoba rhizogenesis. An experiment was carried out in a Factorial Completely Randomized Design (FCRD) with three replications, each with sixty cuttings per replication in fiberglass house of Natural Jojoba Corporation at Yemen. The different rooting media used were peat moss + perlite + vermiculite (1:1:1), peat moss + perlite (1:1) and peat moss + sand (1:1). Plant materials used were semi-hard wood cuttings of jojoba plants with length of 15 cm. The cuttings were collected in the month of June during 2012 and 2013 from the sub-terminal growth of the mother plants of Amman farm and introduced to Yemen. They were wounded, treated with Indole butyric acid (IBA), α-naphthalene acetic acid (NAA) or Indole-3-acetic acid (IAA) all @ 4000 ppm (part per million) and cultured on different rooting media under intermittent mist propagation conditions. IBA gave significantly higher percentage of rooting (66.23%) compared to NAA and IAA in all media used. However, the lowest percentage of rooting (5.33%) was recorded with IAA in the medium consisting of peat moss and sand (1:1). No significant difference was observed at all types of PGRs used with rooting media in respect of root length. Maximum number of roots was noticed in medium consisting of peat moss, perlite and vermiculite (1:1:1); peat moss and perlite (1:1) and peat moss and sand (1:1) using IBA, NAA and IBA, respectively. The interaction among rooting media was statistically significant with respect to rooting percentage character. Similarly, the interactions among PGRs were significant in terms of rooting percentage and also root length characters. The results demonstrated suitability of propagation of jojoba plants by semi-hard wood cuttings.

Keywords: cutting, IBA, Jojoba, propagation, rhizogenesis

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1678 The Quality of Fishery Product on the Moldovan Market, Regulations, National Institutions, Controls and Non-Compliant Products

Authors: Mihaela Munteanu (Pila), Silvius Stanciu

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This paper presents the aspects of the official control of fishery in the Republic of Moldova. Currently, the regulations and the activity of national institutions with responsibilities in the field of food quality are in a process of harmonization with the European rules, aiming at European integration, quality improvement and providing a higher level of food safety. The National Agency for Food Safety is the main national body with responsibilities in the field of food safety. In the field of fishery products, the Agency carries out an intensive activity of informing the citizen and controlling the products marketed. The paper presents the dangers related to the consumption of fish and fishery products traded on the national market, the sanitary-veterinary inspections conducted by the profile institution and the improper situations identified. The national market of fishery products depends largely on imports, mainly focused on ocean fish. The research carried out has shown that during the period 2011-2018, following the inspections carried out on fishery products traded on the national market, a number of inconsistencies have been identified. Thus, indigenous products were frequently detected with sensory characteristics unfit for consumption, and being commercialized in inappropriate locations or contaminated with chemical pollutants. On import products controlled, the most frequent inconsistent situations have been represented by inconsistent sensory aspects and by parasite contamination. Taking into account the specific aspects of aquatic products, including the high level of alterability, special conditions of growth, marketing, culinary preparation and consumption are necessary in order to decrease the risk of disease over the population. Certificates, attestations and other documents certifying the quality of batches, completed by additional laboratory examinations, are necessary in order to increase the level of confidence on the quality of products marketed in the Republic. The implementation of various control procedures and mechanisms at national level, correlated with the focused activity of the specialized institutions, can decrease the risk of contamination and avoid cases of disease on the population due to the consumption of fishery products.

Keywords: fishery products, food safety, quality control, Republic of Moldova

Procedia PDF Downloads 151
1677 Application of Compressed Sensing and Different Sampling Trajectories for Data Reduction of Small Animal Magnetic Resonance Image

Authors: Matheus Madureira Matos, Alexandre Rodrigues Farias

Abstract:

Magnetic Resonance Imaging (MRI) is a vital imaging technique used in both clinical and pre-clinical areas to obtain detailed anatomical and functional information. However, MRI scans can be expensive, time-consuming, and often require the use of anesthetics to keep animals still during the imaging process. Anesthetics are commonly administered to animals undergoing MRI scans to ensure they remain still during the imaging process. However, prolonged or repeated exposure to anesthetics can have adverse effects on animals, including physiological alterations and potential toxicity. Minimizing the duration and frequency of anesthesia is, therefore, crucial for the well-being of research animals. In recent years, various sampling trajectories have been investigated to reduce the number of MRI measurements leading to shorter scanning time and minimizing the duration of animal exposure to the effects of anesthetics. Compressed sensing (CS) and sampling trajectories, such as cartesian, spiral, and radial, have emerged as powerful tools to reduce MRI data while preserving diagnostic quality. This work aims to apply CS and cartesian, spiral, and radial sampling trajectories for the reconstruction of MRI of the abdomen of mice sub-sampled at levels below that defined by the Nyquist theorem. The methodology of this work consists of using a fully sampled reference MRI of a female model C57B1/6 mouse acquired experimentally in a 4.7 Tesla MRI scanner for small animals using Spin Echo pulse sequences. The image is down-sampled by cartesian, radial, and spiral sampling paths and then reconstructed by CS. The quality of the reconstructed images is objectively assessed by three quality assessment techniques RMSE (Root mean square error), PSNR (Peak to Signal Noise Ratio), and SSIM (Structural similarity index measure). The utilization of optimized sampling trajectories and CS technique has demonstrated the potential for a significant reduction of up to 70% of image data acquisition. This result translates into shorter scan times, minimizing the duration and frequency of anesthesia administration and reducing the potential risks associated with it.

Keywords: compressed sensing, magnetic resonance, sampling trajectories, small animals

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1676 Seismic Retrofit of Tall Building Structure with Viscous, Visco-Elastic, Visco-Plastic Damper

Authors: Nicolas Bae, Theodore L. Karavasilis

Abstract:

Increasingly, a large number of new and existing tall buildings are required to improve their resilient performance against strong winds and earthquakes to minimize direct, as well as indirect damages to society. Those advent stationary functions of tall building structures in metropolitan regions can be severely hazardous, in socio-economic terms, which also increase the requirement of advanced seismic performance. To achieve these progressive requirements, the seismic reinforcement for some old, conventional buildings have become enormously costly. The methods of increasing the buildings’ resilience against wind or earthquake loads have also become more advanced. Up to now, vibration control devices, such as the passive damper system, is still regarded as an effective and an easy-to-install option, in improving the seismic resilience of buildings at affordable prices. The main purpose of this paper is to examine 1) the optimization of the shape of visco plastic brace damper (VPBD) system which is one of hybrid damper system so that it can maximize its energy dissipation capacity in tall buildings against wind and earthquake. 2) the verification of the seismic performance of the visco plastic brace damper system in tall buildings; up to forty-storey high steel frame buildings, by comparing the results of Non-Linear Response History Analysis (NLRHA), with and without a damper system. The most significant contribution of this research is to introduce the optimized hybrid damper system that is adequate for high rise buildings. The efficiency of this visco plastic brace damper system and the advantages of its use in tall buildings can be verified since tall buildings tend to be affected by wind load at its normal state and also by earthquake load after yielding of steel plates. The modeling of the prototype tall building will be conducted using the Opensees software. Three types of modeling were used to verify the performance of the damper (MRF, MRF with visco-elastic, MRF with visco-plastic model) 22-set seismic records used and the scaling procedure was followed according to the FEMA code. It is shown that MRF with viscous, visco-elastic damper, it is superior effective to reduce inelastic deformation such as roof displacement, maximum story drift, roof velocity compared to the MRF only.

Keywords: tall steel building, seismic retrofit, viscous, viscoelastic damper, performance based design, resilience based design

Procedia PDF Downloads 190
1675 Effect of Human Resources Accounting on Financial Performance of Banks in Nigeria

Authors: Oti Ibiam, Alexanda O. Kalu

Abstract:

Human Resource Accounting is the process of identifying and measuring data about human resources and communicating this information to interested parties in order to meaningful investment decisions. In recent time, firms focus has shifted to human resource accounting so as to ensure efficiency and effectiveness in their operations. This study focused on the effect of human resource accounting on the financial performance of Banks in Nigerian. The problem that led to the study revolves around the current trend whereby Nigeria banks do not efficiently account for the input of human resource in their annual statement, thereby instead of capitalizing human resources in their statement of financial position; they expend it in their income statement thereby reducing their profit after tax. The broad objective of this study is to determine the extent to which human resource accounting affects the financial performance and value of Nigerian Banks. This study is therefore considered significant because, there are still universally, grey areas to be sorted out on the subject matter of human resources accounting. In the bid to achieve the study objectives, the researcher gathered data from sixteen commercial banks. Data were collected from both primary and secondary sources using an ex-post facto research design. The data collected were then tabulated and analyzed using the multiple regression analysis. The result of hypothesis one revealed that there is a significant relationship between Capitalized Human Resource Cost and post capitalization Profit before tax of banks in Nigeria. The finding of hypothesis two revealed that the association between Capitalized Human Resource Cost and post capitalization Net worth of banks in Nigeria is significant. The finding in Hypothesis three reveals that there is a significant difference between pre and post capitalization profit before tax of banks in Nigeria. The study concludes that human resources accounting positively influenced financial performance of banks in Nigeria within the period under study. It is recommended that standards should be set for human resources identification and measurement in the banking sector and also the management of commercial banks in Nigeria should have a proper appreciation of human resource accounting. This will enable managers to take right decision regarding investment in human resource. Also, the study recommends that policies on enhancing the post capitalization profit before tax of banks in Nigeria should pay great attention to capitalized human resources cost, net worth and total asset as the variables significantly influenced post capitalization profit before tax of the studied banks in Nigeria. The limitation of the study centers on the limited number of years and companies that was adopted for the study.

Keywords: capitalization, human resources cost, profit before tax, net worth

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1674 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

Abstract:

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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1673 Umkhonto Wesizwe as the Foundation of Post-Apartheid South Africa’s Foreign Policy and International Relations.

Authors: Bheki R. Mngomezulu

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The present paper cogently and systematically traces the history of Umkhonto Wesizwe (MK) and identifies its important role in shaping South Africa’s post-apartheid foreign policy and international relations under black leadership. It provides the political and historical contexts within which we can interpret and better understand South Africa’s controversial ‘Quiet Diplomacy’ approach to Zimbabwe’s endemic political and economic crises, which have dragged for too long. On 16 December 1961, the African National Congress (ANC) officially launched the MK as its military wing. The main aim was to train liberation fighters outside South Africa who would return into the country to topple the apartheid regime. Subsequently, the ANC established links with various countries across Africa and the globe in order to solicit arms, financial resources and military training for its recruits into the MK. Drawing from archival research and empirical data obtained through oral interviews that were conducted with some of the former MK cadres, this paper demonstrates how the ANC forged relations with a number of countries that were like-minded in order to ensure that its dream of removing the apartheid government became a reality. The findings reveal that South Africa’s foreign policy posture and international relations after the demise of apartheid in 1994 built on these relations. As such, even former and current socialist countries that were frowned upon by the Western world became post-apartheid South Africa’s international partners. These include countries such as Cuba and China, among others. Even countries that were not recognized by the Western world as independent states received good reception in post-apartheid South Africa’s foreign policy agenda. One of these countries is Palestine. Within Africa, countries with questionable human rights records such as Nigeria and Zimbabwe were accommodated in South Africa’s foreign policy agenda after 1994. Drawing from this history, the paper concludes that it would be difficult to fully understand and appreciate South Africa’s foreign policy direction and international relations after 1994 without bringing the history and the politics of the MK into the equation. Therefore, the paper proposes that the utilitarian role of history should never be undermined in the analysis of a country’s foreign policy direction and international relations. Umkhonto Wesizwe and South Africa are used as examples to demonstrate how such a link could be drawn through archival and empirical evidence.

Keywords: African National Congress, apartheid, foreign policy, international relations

Procedia PDF Downloads 184
1672 Characterisation of Human Attitudes in Software Requirements Elicitation

Authors: Mauro Callejas-Cuervo, Andrea C. Alarcon-Aldana

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It is evident that there has been progress in the development and innovation of tools, techniques and methods in the development of software. Even so, there are few methodologies that include the human factor from the point of view of motivation, emotions and impact on the work environment; aspects that, when mishandled or not taken into consideration, increase the iterations in the requirements elicitation phase. This generates a broad number of changes in the characteristics of the system during its developmental process and an overinvestment of resources to obtain a final product that, often, does not live up to the expectations and needs of the client. The human factors such as emotions or personality traits are naturally associated with the process of developing software. However, most of these jobs are oriented towards the analysis of the final users of the software and do not take into consideration the emotions and motivations of the members of the development team. Given that in the industry, the strategies to select the requirements engineers and/or the analysts do not take said factors into account, it is important to identify and describe the characteristics or personality traits in order to elicit requirements effectively. This research describes the main personality traits associated with the requirements elicitation tasks through the analysis of the existing literature on the topic and a compilation of our experiences as software development project managers in the academic and productive sectors; allowing for the characterisation of a suitable profile for this job. Moreover, a psychometric test is used as an information gathering technique, and it is applied to the personnel of some local companies in the software development sector. Such information has become an important asset in order to make a comparative analysis between the degree of effectiveness in the way their software development teams are formed and the proposed profile. The results show that of the software development companies studied: 53.58% have selected the personnel for the task of requirements elicitation adequately, 37.71% possess some of the characteristics to perform the task, and 10.71% are inadequate. From the previous information, it is possible to conclude that 46.42% of the requirements engineers selected by the companies could perform other roles more adequately; a change which could improve the performance and competitiveness of the work team and, indirectly, the quality of the product developed. Likewise, the research allowed for the validation of the pertinence and usefulness of the psychometric instrument as well as the accuracy of the characteristics for the profile of requirements engineer proposed as a reference.

Keywords: emotions, human attitudes, personality traits, psychometric tests, requirements engineering

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1671 Analysis of Sentinel Epidemiological Surveillance of Severe Acute Respiratory Infections in the Republic of Kazakhstan during Seasons 2014/2015 - 2015/2016

Authors: Ardak Myrzabekova

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Sentinel epidemiological surveillance (SES) of severe acute respiratory infections (SARI) was introduced in the Republic of Kazakhstan in 2008. The purpose of this study was to analyze SES of flu among SARI patients in the Republic of Kazakhstan during last two flu seasons. Comparative analysis was conducted of SARI morbidity during 40 – 23 weeks of 2014/2015 (season 2014) and 2015/2016 (season 2015) in online base (http:\\ses.dec.kz). In the database during season 2014 were 1,398 SARI patients and 1,985 patients during season 2015. Individual data (clinical, epidemiological and laboratory) of SARI cases were collected based on the questionnaire and were put into the flu electronic system. The studied population was residents of the Republic of Kazakhstan who addressed for medical help in 24 sentinel in-patient clinics in 9 sentinel regions of the country. Swabs from nose and throat were taken for laboratory testing from SARI patients who met the standard case definition. The samples were examined in virology labs of sentinel regions using PCR and 'AmpliSens' test systems made in Russia. The first positive results for flu during season 2014 were obtained on 48 week, during season 2015 – on 46 week. The increase of the number of hospitalized SARI patients was observed during 42 week of 2015 – 01 week of 2016, and during 03 - 06 weeks of 2016, with fluctuating SARI incidence rate from 171 to 444 per 1,000 hospitalized. The highest SARI incidence rate during season 2014 were observed during 01 - 03 weeks of 2015: from 389 to 466 per 1,000 hospitalized. Patients admitted to the ICU during season 2015 were 3.0% (60) SARI patients, compared to 2.7% (38) in 2014 (p=0.3), obtaining oxygen therapy 1.0% (21) compared to 0.3% (5), accordingly, (р=0.009); with shortness of breath 74.8% (1,486) compared to 72.6% (1,015), (р=0.07); with impairment of consciousness 1.0% (21) compared to 0.6% (9), (р=0.11); with muscle pain 19.3% (384) compared to 13.6% (191), (р < 0.001); with joint pain 13.3% (265) compared to 9.3% (131), (p < 0.001). During season 2015 the prevailing subtype of flu А was А/Н1N1-09, it was observed mainly in the age group 30-64: 32.5% (169/520). During season 2014 flu А/Н3N2 was observed mainly in the age group 15-29: 43.6% (106/243). Among children under 14 flu А/Н1N1-09 during season 2015 was 37.3% (194/520), during season 2014 flu А/Н3N2 – 34.9% (85/243). Earlier beginning of the flu season was noted in 2015-2016 and a longer period of hospitalization of SARI patients, with high SARI morbidity rates, unlike season 2014-2015. Season 2015-2016 was characterized by prevailing circulation of virus of flu А/Н1N1-09, mainly in the age group 30-64, and also among children under 14. During season 2014-2015 the virus circulating in the country was А/Н3N2, which was observed mainly in the age group 15-29 and among children under 14.

Keywords: flu, electronic system, sentinel epidemiological surveillance, severe acute respiratory infections

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1670 Fabrication and Characterisation of Additive Manufactured Ti-6Al-4V Parts by Laser Powder Bed Fusion Technique

Authors: Norica Godja, Andreas Schindel, Luka Payrits, Zsolt Pasztor, Bálint Hegedüs, Petr Homola, Jan Horňas, Jiří Běhal, Roman Ruzek, Martin Holzleitner, Sascha Senck

Abstract:

In order to reduce fuel consumption and CO₂ emissions in the aviation sector, innovative solutions are being sought to reduce the weight of aircraft, including additive manufacturing (AM). Of particular importance are the excellent mechanical properties that are required for aircraft structures. Ti6Al4V alloys, with their high mechanical properties in relation to weight, can reduce the weight of aircraft structures compared to structures made of steel and aluminium. Currently, conventional processes such as casting and CNC machining are used to obtain the desired structures, resulting in high raw material removal, which in turn leads to higher costs and impacts the environment. Additive manufacturing (AM) offers advantages in terms of weight, lead time, design, and functionality and enables the realisation of alternative geometric shapes with high mechanical properties. However, there are currently technological shortcomings that have led to AM not being approved for structural components with high safety requirements. An assessment of damage tolerance for AM parts is required, and quality control needs to be improved. Pores and other defects cannot be completely avoided at present, but they should be kept to a minimum during manufacture. The mechanical properties of the manufactured parts can be further improved by various treatments. The influence of different treatment methods (heat treatment, CNC milling, electropolishing, chemical polishing) and operating parameters were investigated by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX), X-ray diffraction (XRD), electron backscatter diffraction (EBSD) and measurements with a focused ion beam (FIB), taking into account surface roughness, possible anomalies in the chemical composition of the surface and possible cracks. The results of the characterisation of the constructed and treated samples are discussed and presented in this paper. These results were generated within the framework of the 3TANIUM project, which is financed by EU with the contract number 101007830.

Keywords: Ti6Al4V alloys, laser powder bed fusion, damage tolerance, heat treatment, electropolishing, potential cracking

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1669 Seasonal Variations, Environmental Parameters, and Standing Crop Assessment of Benthic Foraminifera in Western Bahrain, Arabian Gulf

Authors: Muhammad Arslan, Michael A. Kaminski, Bassam S. Tawabini, Fabrizio Frontalini

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We conducted a survey of living benthic foraminifera in a relatively unpolluted site of Bahrain in the Arabian Gulf, with the aim of determining the seasonal variability in their populations, as well as various environmental parameters that affect their distribution. The maximum standing crop was observed during winter, with highest population of rotaliids, followed by a peak in miliolids. The highest population is attributed to an increasing number juveniles observed along the depth transect. A strong correlation between sediment grain size and the foraminiferal population indicates that juveniles were most abundant on coarser sandy substrate and less abundant on fine substrate. In spring, the total living population decreased, and lowest values are observed in the summer. The population started to increase again in the autumn with highest juveniles/adult ratios. Moreover, results of relative abundance and species consistency show that Ammonia is found to be consistent from the shallowest to the deepest station, whereas miliolids start appearing in the deeper stations. The average numbers of Peneroplis and Elphidium also increases along the depth transect. Environmental characterization reveals that although the site is subjected to eutrophication caused by nitrates and sulfates, pollution caused by hydrocarbons and heavy metals is not significant. The assessment of 63 heavy metals showed that none of the metals had concentrations that exceed internationally accepted norms [the devised level of Effect Range-Low], with the exception of strontium. The lack of a significant environmental effect of heavy metals is confirmed by a Foraminiferal Deformities Index value of less than 2%. Likewise, no hydrocarbon contamination was detected in the water or sediment samples. Lastly, observations of cytoplasmic streaming and pseudopodial activity in Petri dishes suggest that the foraminiferal population is not stressed. We conclude that the site in Bahrain is not yet adversely affected by human development, and therefore can provide baseline information for future comparison and assessment of foraminiferal assemblages in contaminated zones of the Arabian Gulf.

Keywords: Arabian Gulf, benthic foraminifera, standing crop, Western Bahrain

Procedia PDF Downloads 641
1668 Spatial Analysis as a Tool to Assess Risk Management in Peru

Authors: Josué Alfredo Tomas Machaca Fajardo, Jhon Elvis Chahua Janampa, Pedro Rau Lavado

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A flood vulnerability index was developed for the Piura River watershed in northern Peru using Principal Component Analysis (PCA) to assess flood risk. The official methodology to assess risk from natural hazards in Peru was introduced in 1980 and proved effective for aiding complex decision-making. This method relies in part on decision-makers defining subjective correlations between variables to identify high-risk areas. While risk identification and ensuing response activities benefit from a qualitative understanding of influences, this method does not take advantage of the advent of national and international data collection efforts, which can supplement our understanding of risk. Furthermore, this method does not take advantage of broadly applied statistical methods such as PCA, which highlight central indicators of vulnerability. Nowadays, information processing is much faster and allows for more objective decision-making tools, such as PCA. The approach presented here develops a tool to improve the current flood risk assessment in the Peruvian basin. Hence, the spatial analysis of the census and other datasets provides a better understanding of the current land occupation and a basin-wide distribution of services and human populations, a necessary step toward ultimately reducing flood risk in Peru. PCA allows the simplification of a large number of variables into a few factors regarding social, economic, physical and environmental dimensions of vulnerability. There is a correlation between the location of people and the water availability mainly found in rivers. For this reason, a comprehensive vision of the population location around the river basin is necessary to establish flood prevention policies. The grouping of 5x5 km gridded areas allows the spatial analysis of flood risk rather than assessing political divisions of the territory. The index was applied to the Peruvian region of Piura, where several flood events occurred in recent past years, being one of the most affected regions during the ENSO events in Peru. The analysis evidenced inequalities for the access to basic services, such as water, electricity, internet and sewage, between rural and urban areas.

Keywords: assess risk, flood risk, indicators of vulnerability, principal component analysis

Procedia PDF Downloads 183
1667 Impact of Electric Vehicles on Energy Consumption and Environment

Authors: Amela Ajanovic, Reinhard Haas

Abstract:

Electric vehicles (EVs) are considered as an important means to cope with current environmental problems in transport. However, their high capital costs and limited driving ranges state major barriers to a broader market penetration. The core objective of this paper is to investigate the future market prospects of various types of EVs from an economic and ecological point of view. Our method of approach is based on the calculation of total cost of ownership of EVs in comparison to conventional cars and a life-cycle approach to assess the environmental benignity. The most crucial parameters in this context are km driven per year, depreciation time of the car and interest rate. The analysis of future prospects it is based on technological learning regarding investment costs of batteries. The major results are the major disadvantages of battery electric vehicles (BEVs) are the high capital costs, mainly due to the battery, and a low driving range in comparison to conventional vehicles. These problems could be reduced with plug-in hybrids (PHEV) and range extenders (REXs). However, these technologies have lower CO₂ emissions in the whole energy supply chain than conventional vehicles, but unlike BEV they are not zero-emission vehicles at the point of use. The number of km driven has a higher impact on total mobility costs than the learning rate. Hence, the use of EVs as taxis and in car-sharing leads to the best economic performance. The most popular EVs are currently full hybrid EVs. They have only slightly higher costs and similar operating ranges as conventional vehicles. But since they are dependent on fossil fuels, they can only be seen as energy efficiency measure. However, they can serve as a bridging technology, as long as BEVs and fuel cell vehicle do not gain high popularity, and together with PHEVs and REX contribute to faster technological learning and reduction in battery costs. Regarding the promotion of EVs, the best results could be reached with a combination of monetary and non-monetary incentives, as in Norway for example. The major conclusion is that to harvest the full environmental benefits of EVs a very important aspect is the introduction of CO₂-based fuel taxes. This should ensure that the electricity for EVs is generated from renewable energy sources; otherwise, total CO₂ emissions are likely higher than those of conventional cars.

Keywords: costs, mobility, policy, sustainability,

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1666 Nursing Students' Experience of Using Electronic Health Record System in Clinical Placements

Authors: Nurten Tasdemir, Busra Baloglu, Zeynep Cingoz, Can Demirel, Zeki Gezer, Barıs Efe

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Student nurses are increasingly exposed to technology in the workplace after graduation with the growing numbers of electric health records (EHRs), handheld computers, barcode scanner medication dispensing systems, and automatic capture of patient data such as vital signs. Internationally, electronic health records (EHRs) systems are being implemented and evaluated. Students will inevitably encounter EHRs in the clinical learning environment and their professional practice. Nursing students must develop competency in the use of EHR. Aim: The study aimed to examine nursing students’ experiences of learning to use electronic health records (EHR) in clinical placements. Method: This study adopted a descriptive approach. The study population consisted of second and third-year nursing students at the Zonguldak School of Health in the West Black Sea Region of Turkey; the study was conducted during the 2015–2016 academic year. The sample consisted of 315 (74.1% of 425 students) nursing students who volunteered to participate. The students, who were involved in clinical practice, were invited to participate in the study Data were collected by a questionnaire designed by the researchers based on the relevant literature. Data were analyzed descriptively using the Statistical Package for Social Sciences (SPSS) for Windows version 16.0. The data are presented as means, standard deviations, and percentages. Approval for the study was obtained from the Ethical Committee of the University (Reg. Number: 29/03/2016/112) and the director of Nursing Department. Findings: A total of 315 students enrolled in this study, for a response rate of 74.1%. The mean age of the sample was 22.24 ± 1.37 (min: 19, max: 32) years, and most participants (79.7%) were female. Most of the nursing students (82.3%) stated that they use information technologies in clinical practice. Nearly half of the students (42.5%) reported that they have not accessed to EHR system. In addition, 61.6% of the students reported that insufficient computers available in clinical placement. Of the students, 84.7% reported that they prefer to have patient information from EHR system, and 63.8% of them found more effective to preparation for the clinical reporting. Conclusion: This survey indicated that nursing students experience to learn about EHR systems in clinical placements. For more effective learning environment nursing education should prepare nursing students for EHR systems in their educational life.

Keywords: electronic health record, clinical placement, nursing student, nursing education

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1665 Identifying Diabetic Retinopathy Complication by Predictive Techniques in Indian Type 2 Diabetes Mellitus Patients

Authors: Faiz N. K. Yusufi, Aquil Ahmed, Jamal Ahmad

Abstract:

Predicting the risk of diabetic retinopathy (DR) in Indian type 2 diabetes patients is immensely necessary. India, being the second largest country after China in terms of a number of diabetic patients, to the best of our knowledge not a single risk score for complications has ever been investigated. Diabetic retinopathy is a serious complication and is the topmost reason for visual impairment across countries. Any type or form of DR has been taken as the event of interest, be it mild, back, grade I, II, III, and IV DR. A sample was determined and randomly collected from the Rajiv Gandhi Centre for Diabetes and Endocrinology, J.N.M.C., A.M.U., Aligarh, India. Collected variables include patients data such as sex, age, height, weight, body mass index (BMI), blood sugar fasting (BSF), post prandial sugar (PP), glycosylated haemoglobin (HbA1c), diastolic blood pressure (DBP), systolic blood pressure (SBP), smoking, alcohol habits, total cholesterol (TC), triglycerides (TG), high density lipoprotein (HDL), low density lipoprotein (LDL), very low density lipoprotein (VLDL), physical activity, duration of diabetes, diet control, history of antihypertensive drug treatment, family history of diabetes, waist circumference, hip circumference, medications, central obesity and history of DR. Cox proportional hazard regression is used to design risk scores for the prediction of retinopathy. Model calibration and discrimination are assessed from Hosmer Lemeshow and area under receiver operating characteristic curve (ROC). Overfitting and underfitting of the model are checked by applying regularization techniques and best method is selected between ridge, lasso and elastic net regression. Optimal cut off point is chosen by Youden’s index. Five-year probability of DR is predicted by both survival function, and Markov chain two state model and the better technique is concluded. The risk scores developed can be applied by doctors and patients themselves for self evaluation. Furthermore, the five-year probabilities can be applied as well to forecast and maintain the condition of patients. This provides immense benefit in real application of DR prediction in T2DM.

Keywords: Cox proportional hazard regression, diabetic retinopathy, ROC curve, type 2 diabetes mellitus

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1664 Development of Stretchable Woven Fabrics with Auxetic Behaviour

Authors: Adeel Zulifqar, Hong Hu

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Auxetic fabrics are a special kind of textile materials which possess negative Poisson’s ratio. Opposite to most of the conventional fabrics, auxetic fabrics get bigger in the transversal direction when stretched or get smaller when compressed. Auxetic fabrics are superior to conventional fabrics because of their counterintuitive properties, such as enhanced porosity under the extension, excellent formability to a curved surface and high energy absorption ability. Up till today, auxetic fabrics have been produced based on two approaches. The first approach involves using auxetic fibre or yarn and weaving technology to fabricate auxetic fabrics. The other method to fabricate the auxetic fabrics is by using non-auxetic yarns. This method has gained extraordinary curiosity of researcher in recent years. This method is based on realizing auxetic geometries into the fabric structure. In the woven fabric structure auxetic geometries can be realized by creating a differential shrinkage phenomenon into the fabric structural unit cell. This phenomenon can be created by using loose and tight weave combinations within the unit cell of interlacement pattern along with elastic and non-elastic yarns. Upon relaxation, the unit cell of interlacement pattern acquires a non-uniform shrinkage profile due to different shrinkage properties of loose and tight weaves in designed pattern, and the auxetic geometry is realized. The development of uni-stretch auxetic woven fabrics and bi-stretch auxetic woven fabrics by using this method has already been reported. This study reports the development of another kind of bi-stretch auxetic woven fabric. The fabric is first designed by transforming the auxetic geometry into interlacement pattern and then fabricated, using the available conventional weaving technology and non-auxetic elastic and non-elastic yarns. The tensile tests confirmed that the developed bi-stretch auxetic woven fabrics exhibit negative Poisson’s ratio over a wide range of tensile strain. Therefore, it can be concluded that the auxetic geometry can be realized into the woven fabric structure by creating the phenomenon of differential shrinkage and bi-stretch woven fabrics made of non-auxetic yarns having auxetic behavior and stretchability are possible can be obtained. Acknowledgement: This work was supported by the Research Grants Council of Hong Kong Special Administrative Region Government (grant number 15205514).

Keywords: auxetic, differential shrinkage, negative Poisson's ratio, weaving, stretchable

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1663 An Exploratory Study of Vocational High School Students’ Needs in Learning English

Authors: Yi-Hsuan Gloria Lo

Abstract:

The educational objective of vocational high schools (VHSs) is to equip VHS students with practical skills and knowledge that can be applied in the job-related market. However, with the increasing number of technological universities over the past two decades, the majority of VHS students have chosen to receive higher education rather than enter the job market. VHS English education has been confronting a dilemma: Should an English for specific purposes (ESP) approach, which aligns with the educational goal of VHS education, be taken or should an English for general purposes (EGP) approach, which prepares VHS students for advanced studies in universities, be followed? While ESP theorists proposed that that ESP can be taught to secondary learners, little was known about VHS students’ perspective on this ESP-versus-EGP dilemma. Scant research has investigated different facets of students’ needs (necessities, wants, and lacks) for both ESP and EGP in terms of the four language skills and the factors that contribute to any differences. To address the gap in the literature, 100 VHS students responded to statements related to their necessities, wants, and lacks in learning ESP and EGP on a 6-point Likert scale. Six VHS students were interviewed to tap into the reasons for different facets of the needs for learning EGP and ESP. The statistical analysis indicates that at this stage of learning English, VHS subjects believed that EGP was more necessary than ESP; EGP was more desirable than ESP. However, they reported that they were more lacking in ESP than in EGP learning. Regarding EGP, the results show that the VHS subjects rated speaking as their most necessary skill, speaking as the most desirable skill, and writing as the most lacking skill. A significant difference was found between perceived learning necessities and lacks and between perceived wants and lacks. No statistical difference was found between necessities and wants. In the aspect of ESP, the results indicate that the VHS subjects marked reading as their most necessary skill, speaking as the most desirable skill, and writing as the most lacking skill. A significant difference exists between their perceived necessities and lacks and between their wants and lacks. However, there is no statistically significant difference between their perceived lacks and wants. Despite the lack of a significant difference between learning necessities and wants, the qualitative interview data reveal that the reasons for their perceived necessities and wants were different. The findings of the study confirm previous research that demonstrates that ‘needs’ is a multiple and conflicting construct. What VHS students felt most lacking was not necessarily what they believed they should learn or would like to learn. Although no statistical difference was found, different reasons were attributed to their perceived necessities and wants. Both theoretical and practical implications have been drawn and discussed for ESP research in general and teaching ESP in VHSs in particular.

Keywords: vocational high schools (VHSs), English for General Purposes (EGP), English for Specific Purposes (ESP), needs analysis

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