Search results for: analytical systems engineering process
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 25468

Search results for: analytical systems engineering process

4498 Talent Management in Small and Medium Sized Companies: A Multilevel Approach Contextualized in France

Authors: Kousay Abid

Abstract:

The aim of this paper is to better understand talent and talent management (TM) in small French companies as well as in medium-sized ones (SME). While previous empirical investigations have largely focused on multinationals and big companies and concentrated on the Anglo-Saxon context, we focus on the pressing need for implementing TM strategies and practices, not only on a new ground of SME but also within a new European context related to France and the French context. This study also aims at understanding strategies adopted by those firms as means to attract, retain, maintain and to develop talents. We contribute to TM issues by adopting a multilevel approach, holding the goal of reaching a global holistic vision of interactions between various levels while applying TM, to make it more and more familiar to us. A qualitative research methodology based on a multiple-case study design, bottomed firstly on a qualitative survey and secondly on two in-depth case study, both built on interviews, will be used in order to develop an ideal analysis for TM strategies and practices. The findings will be based on data collected from more than 15 French SMEs. Our theoretical contributions are the fruit of context considerations and the dynamic of multilevel approach. Theoretically, we attempt first to clarify how talents and TM are seen and defined in French SMEs and consequently to enrich the literature on TM in SMEs out of the Anglo-Saxon context. Moreover, we seek to understand how SMEs manage jointly their talents and their TM strategies by setting up this contextualized pilot study. As well, we focus on the systematic TM model issue from French SMEs. Our prior managerial goal is to shed light on the need for TM to achieve a better management of these organizations by directing leaders to better identify the talented people whom they hold at all levels. In addition, our TM systematic model strengthens our analysis grid as recommendations for CEO and Human Resource Development (HRD) to make them rethink about the companies’ HR business strategies. Therefore, our outputs present a multiple lever of action that should be taken into consideration while reviewing HR strategies and systems, as well as their impact beyond organizational boundaries.

Keywords: french context, multilevel approach, small and medium-sized enterprises, talent management

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4497 Ratification of the United Nations Convention for the Promotion and Protection of Their Human Rights and the Paradoxes of the Discriminatory Right to Acquire the Status of Persons with Disabilities in Cameroon

Authors: Dakeyi Athanase

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The ratification of an international human rights legal instrument provides signatory States with an opportunity to assume a set of obligations and rights for the benefit of their citizens, offering increased possibilities, opportunities, and means to access an improved quality of life – to be, to appear, and to become. Developed nations typically experience cultural, political, social, economic, legal, and regulatory transformations in response to this transition. In a methodologically proactive approach, mechanisms undergo a visible and comprehensible process of qualitative and quantitative change. Conversely, in nations undergoing development, the response to such ratification varies. Some demonstrate positive policy changes, while others remain stagnant or regress. Cameroon falls into the second category, despite efforts, as it legally prohibits 50% of its population with disabilities from acquiring the status of a person with a disability. The overarching goal of this communication is to highlight these deficiencies and their detrimental effects on various aspects of life, fostering awareness among beneficiaries and advocating for more inclusive transformations in the country. Our project employs a popular and participatory methodological approach by involving beneficiaries and their organizations in its preparation. It is also inclusive, representing the diversity of disabilities and engaging natural and legal persons from various backgrounds. Active consultations occur at all levels of the activities. Anticipated outcomes include raising awareness globally among nations, international cooperation organizations, NGOs, and other inclusive development actors. We seek their support for local advocacy efforts to fully implement the United Nations Convention on the Rights of Persons with Disabilities (CRPD). Concurrently, we hope they express solidarity with the victims in Cameroon who have been left behind and recommend legal reforms to align domestic and international legislation with the promotion and protection of disability rights.

Keywords: droit, convention, handicap, discrimination, participation, inclusion

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4496 Enhancing Learning for Research Higher Degree Students

Authors: Jenny Hall, Alison Jaquet

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Universities’ push toward the production of high quality research is not limited to academic staff and experienced researchers. In this environment of research rich agendas, Higher Degree Research (HDR) students are increasingly expected to engage in the publishing of good quality papers in high impact journals. IFN001: Advanced Information Research Skills (AIRS) is a credit bearing mandatory coursework requirement for Queensland University of Technology (QUT) doctorates. Since its inception in 1989, this unique blended learning program has provided the foundations for new researchers to produce original and innovative research. AIRS was redeveloped in 2012, and has now been evaluated with reference to the university’s strategic research priorities. Our research is the first comprehensive evaluation of the program from the learner perspective. We measured whether the program develops essential transferrable skills and graduate capabilities to ensure best practice in the areas of publishing and data management. In particular, we explored whether AIRS prepares students to be agile researchers with the skills to adapt to different research contexts both within and outside academia. The target group for our study consisted of HDR students and supervisors at QUT. Both quantitative and qualitative research methods were used for data collection. Gathering data was by survey and focus groups with qualitative responses analyzed using NVivo. The results of the survey show that 82% of students surveyed believe that AIRS assisted their research process and helped them learn skills they need as a researcher. The 18% of respondents who expressed reservation about the benefits of AIRS were also examined to determine the key areas of concern. These included trends related to the timing of the program early in the candidature and a belief among some students that their previous research experience was sufficient for postgraduate study. New insights have been gained into how to better support HDR learners in partnership with supervisors and how to enhance learning experiences of specific cohorts, including international students and mature learners.

Keywords: data management, enhancing learning experience, publishing, research higher degree students, doctoral students

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4495 Optimization of Alkali Assisted Microwave Pretreatments of Sorghum Straw for Efficient Bioethanol Production

Authors: Bahiru Tsegaye, Chandrajit Balomajumder, Partha Roy

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The limited supply and related negative environmental consequence of fossil fuels are driving researcher for finding sustainable sources of energy. Lignocellulose biomass like sorghum straw is considered as among cheap, renewable and abundantly available sources of energy. However, lignocellulose biomass conversion to bioenergy like bioethanol is hindered due to the reluctant nature of lignin in the biomass. Therefore, removal of lignin is a vital step for lignocellulose conversion to renewable energy. The aim of this study is to optimize microwave pretreatment conditions using design expert software to remove lignin and to release maximum possible polysaccharides from sorghum straw for efficient hydrolysis and fermentation process. Sodium hydroxide concentration between 0.5-1.5%, v/v, pretreatment time from 5-25 minutes and pretreatment temperature from 120-2000C were considered to depolymerize sorghum straw. The effect of pretreatment was studied by analyzing the compositional changes before and after pretreatments following renewable energy laboratory procedure. Analysis of variance (ANOVA) was used to test the significance of the model used for optimization. About 32.8%-48.27% of hemicellulose solubilization, 53% -82.62% of cellulose release, and 49.25% to 78.29% lignin solubilization were observed during microwave pretreatment. Pretreatment for 10 minutes with alkali concentration of 1.5% and temperature of 1400C released maximum cellulose and lignin. At this optimal condition, maximum of 82.62% of cellulose release and 78.29% of lignin removal was achieved. Sorghum straw at optimal pretreatment condition was subjected to enzymatic hydrolysis and fermentation. The efficiency of hydrolysis was measured by analyzing reducing sugars by 3, 5 dinitrisylicylic acid method. Reducing sugars of about 619 mg/g of sorghum straw were obtained after enzymatic hydrolysis. This study showed a significant amount of lignin removal and cellulose release at optimal condition. This enhances the yield of reducing sugars as well as ethanol yield. The study demonstrates the potential of microwave pretreatments for enhancing bioethanol yield from sorghum straw.

Keywords: cellulose, hydrolysis, lignocellulose, optimization

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4494 Comparison of Susceptibility to Measles in Preterm Infants versus Term Infants

Authors: Joseph L. Mathew, Shourjendra N. Banerjee, R. K. Ratho, Sourabh Dutta, Vanita Suri

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Background: In India and many other developing countries, a single dose of measles vaccine is administered to infants at 9 months of age. This is based on the assumption that maternal transplacentally transferred antibodies will protect infants until that age. However, our previous data showed that most infants lose maternal anti-measles antibodies before 6 months of age, making them susceptible to measles before vaccination at 9 months. Objective: This prospective study was designed to compare susceptibility in pre-term vs term infants, at different time points. Material and Methods: Following Institutional Ethics Committee approval and a formal informed consent process, venous blood was drawn from a cohort of 45 consecutive term infants and 45 consecutive pre-term infants (both groups delivered by the vaginal route); at birth, 3 months, 6 months and 9 months (prior to measles vaccination). Serum was separated and anti-measles IgG antibody levels were measured by quantitative ELISA kits (with sensitivity and specificity > 95%). Susceptibility to measles was defined as antibody titre < 200mIU/ml. The mean antibody levels were compared between the two groups at the four time points. Results: The mean gestation of term babies was 38.5±1.2 weeks; and pre-term babies 34.7±2.8 weeks. The respective mean birth weights were 2655±215g and 1985±175g. Reliable maternal vaccination record was available in only 7 of the 90 mothers. Mean anti-measles IgG antibody (±SD) in terms babies was 3165±533 IU/ml at birth, 1074±272 IU/ml at 3 months, 314±153 IU/ml at 6 months, and 68±21 IU/ml at 9 months. The corresponding levels in pre-term babies were 2875±612 IU/ml, 948±377 IU/ml, 265±98 IU/ml, and 72±33 IU/ml at 9 months (p > 0.05 for all inter-group comparisons). The proportion of susceptible term infants at birth, 3months, 6months and 9months was 0%, 16%, 67% and 96%. The corresponding proportions in the pre-term infants were 0%, 29%, 82%, and 100% (p > 0.05 for all inter-group comparisons). Conclusion: Majority of infants are susceptible to measles before 9 months of age suggesting the need to anticipate measles vaccination, but there was no statistically significant difference between the proportion of susceptible term and pre-term infants, at any of the four-time points. A larger study is required to confirm these findings and compare sero-protection if vaccination is anticipated to be administered between 6 and 9 months.

Keywords: measles, preterm, susceptibility, term infant

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4493 Radio Frequency Energy Harvesting Friendly Self-Clocked Digital Low Drop-Out for System-On-Chip Internet of Things

Authors: Christos Konstantopoulos, Thomas Ussmueller

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Digital low drop-out regulators, in contrast to analog counterparts, provide an architecture of sub-1 V regulation with low power consumption, high power efficiency, and system integration. Towards an optimized integration in the ultra-low-power system-on-chip Internet of Things architecture that is operated through a radio frequency energy harvesting scheme, the D-LDO regulator should constitute the main regulator that operates the master-clock and rest loads of the SoC. In this context, we present a D-LDO with linear search coarse regulation and asynchronous fine regulation, which incorporates an in-regulator clock generation unit that provides an autonomous, self-start-up, and power-efficient D-LDO design. In contrast to contemporary D-LDO designs that employ ring-oscillator architecture which start-up time is dependent on the frequency, this work presents a fast start-up burst oscillator based on a high-gain stage with wake-up time independent of coarse regulation frequency. The design is implemented in a 55-nm Global Foundries CMOS process. With the purpose to validate the self-start-up capability of the presented D-LDO in the presence of ultra-low input power, an on-chip test-bench with an RF rectifier is implemented as well, which provides the RF to DC operation and feeds the D-LDO. Power efficiency and load regulation curves of the D-LDO are presented as extracted from the RF to regulated DC operation. The D-LDO regulator presents 83.6 % power efficiency during the RF to DC operation with a 3.65 uA load current and voltage regulator referred input power of -27 dBm. It succeeds 486 nA maximum quiescent current with CL 75 pF, the maximum current efficiency of 99.2%, and 1.16x power efficiency improvement compared to analog voltage regulator counterpart oriented to SoC IoT loads. Complementary, the transient performance of the D-LDO is evaluated under the transient droop test, and the achieved figure-of-merit is compared with state-of-art implementations.

Keywords: D-LDO, Internet of Things, RF energy harvesting, voltage regulators

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4492 Infusing Social Business Skills into the Curriculum of Higher Learning Institutions with Special Reference to Albukhari International University

Authors: Abdi Omar Shuriye

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A social business is a business designed to address socio-economic problems to enhance the welfare of the communities involved. Lately, social business, with its focus on innovative ideas, is capturing the interest of educational institutions, governments, and non-governmental organizations. Social business uses a business model to achieve a social goal, and in the last few decades, the idea of imbuing social business into the education system of higher learning institutions has spurred much excitement. This is due to the belief that it will lead to job creation and increased social resilience. One of the higher learning institutions which have invested immensely in the idea is Albukhari International University; it is a private education institution, on a state-of-the-art campus, providing an advantageous learning ecosystem. The niche area of this institution is social business, and it graduates job creators, not job seekers; this Malaysian institution is unique and one of its kind. The objective of this paper is to develop a work plan, direction, and milestone as well as the focus area for the infusion of social business into higher learning institutions with special reference to Al-Bukhari International University. The purpose is to develop a prototype and model full-scale to enable higher learning education institutions to construct the desired curriculum fermented with social business. With this model, major predicaments faced by these institutions could be overcome. The paper sets forth an educational plan and will spell out the basic tenets of social business, focusing on the nature and implementational aspects of the curriculum. It will also evaluate the mechanisms applied by these educational institutions. Currently, since research in this area remains scarce, institutions adopt the process of experimenting with various methods to find the best way to reach the desired result on the matter. The author is of the opinion that social business in education is the main tool to educate holistic future leaders; hence educational institutions should inspire students in the classroom to start up their own businesses by adopting creative and proactive teaching methods. This proposed model is a contribution in that direction.

Keywords: social business, curriculum, skills, university

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4491 Bio Based Agro Textiles

Authors: K. Sakthivel

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With the continuous increase in population worldwide, stress increased among agricultural peoples, so it is necessary to increase the yield of agro-products. But it is not possible to meet fully with the traditionally adopted ways of using pesticides and herbicides. Today, agriculture and horticulture has realized the need of tomorrow and opting for various technologies to get higher overall yield, quality agro-products. Most of today’s synthetic polymers are produced from petrochemical bi-products and are not biodegradable. Persistent polymers generate significant sources of environmental pollution, harming wildlife when they are disposed in nature. The disposal of non degradable plastic bags adversely affects human and wild life. Moreover incineration of plastic waste presents environmental issues as well, since it yields toxic emissions. Material incineration is also limited due to the difficulties to find accurate and economically viable outlets. In addition plastic recycling shows a negative eco balance due to the necessity in nearly all cases to wash the plastic waste as well as the energy consumption during the recycling process phases. As plastics represent a large part of the waste collection at the local regional and national levels institutions are aware of the significant savings that compostable or biodegradable materials would generate. Polylactic acid (PLA), which is one of the most important biocompatible polyesters that are derived from annually renewable biomass such as corn and wheat, has attracted much attention for automotive parts and also can be applied in agro textiles. The manufacturing method of PLA is the ring-opening polymerization of the dimeric cyclic ester of lactic acid, lactide. For the stereo complex PLA, we developed by the four unit processes, fermentation, separation, lactide conversion, and polymerization. Then the polymer is converted into mulching film and applied in agriculture field. PLA agro textiles have better tensile strength, tearing strength and with stand from UV rays than polyester agro textile and polypropylene-based products.

Keywords: biodegradation, environment, mulching film, PLA, technical textiles

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4490 Capacities of Early Childhood Education Professionals for the Prevention of Social Exclusion of Children

Authors: Dejana Bouillet, Vlatka Domović

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Both policymakers and researchers recognize that participating in early childhood education and care (ECEC) is useful for all children, especially for those who are exposed to the high risk of social exclusion. Social exclusion of children is understood as a multidimensional construct including economic, social, cultural, health, and other aspects of disadvantage and deprivation, which individually or combined can have an unfavorable effect on the current life and development of a child, as well as on the child’s development and on disadvantaged life chances in adult life. ECEC institutions should be able to promote educational approaches that portray developmental, cultural, language, and other diversity amongst children. However, little is known about the ways in which Croatian ECEC institutions recognize and respect the diversity of children and their families and how they respond to their educational needs. That is why this paper is dedicated to the analysis of the capacities of ECEC professionals to respond to the demands of educational needs of this very diverse group of children and their families. The results obtained in the frame of the project “Models of response to educational needs of children at risk of social exclusion in ECEC institutions,” funded by the Croatian Science Foundation, will be presented. The research methodology arises from explanations of educational processes and risks of social exclusion as a complex and heterogeneous phenomenon. The preliminary results of the qualitative data analysis of educational practices regarding capacities to identify and appropriately respond to the requirements of children at risk of social exclusion will be presented. The data have been collected by interviewing educational staff in 10 Croatian ECEC institutions (n = 10). The questions in the interviews were related to various aspects of inclusive institutional policy, culture, and practices. According to the analysis, it is possible to conclude that Croatian ECEC professionals are still faced with great challenges in the process of implementation of inclusive policies, culture, and practices. There are several baselines of this conclusion. The interviewed educational professionals are not familiar enough with the whole complexity and diversity of needs of children at risk of social exclusion, and the ECEC institutions do not have enough resources to provide all interventions that these children and their families need.

Keywords: children at risk of social exclusion, ECEC professionals, inclusive policies, culture and practices, quallitative analysis

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4489 Soil-Structure Interaction in a Case Study Bridge: Seismic Response under Moderate and Strong Near-Fault Earthquakes

Authors: Nastaran Cheshmehkaboodi, Lotfi Guizani, Noureddine Ghlamallah

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Seismic isolation proves to be a powerful technology in reducing seismic hazards and enhancing overall structural resilience. However, the performance of the technology can be influenced by various factors, including seismic inputs and soil conditions. This research aims to investigate the effects of moderate and strong earthquakes associated with different distances of the source on the seismic responses of conventional and isolated bridges, considering the soil-structure interaction effects. Two groups of moderate and strong near-fault records are applied to the conventional and isolated bridges, with and without considering the underlying soil. For this purpose, using the direct method, three soil properties representing rock, dense, and stiff soils are modeled in Abaqus software. Nonlinear time history analysis is carried out, and structural responses in terms of maximum deck acceleration, deck displacement, and isolation system displacement are studied. The comparison of dynamic responses between both earthquake groups demonstrates a consistent pattern, indicating that the bridge performance and the effects of soil-structure interaction are primarily influenced by the ground motions and their frequency contents. Low ratios of PGA/PGV are found to significantly impact all dynamic responses, resulting in higher force and displacement responses, regardless of the distance associated with the ruptured fault. In addition, displacement responses increase drastically on softer soils. Thus, meticulous consideration is crucial in designing isolation systems to avoid underestimating displacement demands and to ensure sufficient displacement capacity. Despite a lower PGA value in high seismicity areas in this study, the acceleration demand during strong earthquakes is up to 1.3 times higher in conventional bridges and up to 3 times higher in isolated bridges than in moderate earthquakes. Additionally, the displacement demand in strong earthquakes is up to 2 times higher in conventional bridges and up to 5 times higher in isolated bridges compared to moderate earthquakes, highlighting the increased force and displacement demand in strong earthquakes.

Keywords: bridges, seismic isolation, near-fault, earthquake characteristics, soil-structure interaction

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4488 Structural Health Monitoring using Fibre Bragg Grating Sensors in Slab and Beams

Authors: Pierre van Tonder, Dinesh Muthoo, Kim twiname

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Many existing and newly built structures are constructed on the design basis of the engineer and the workmanship of the construction company. However, when considering larger structures where more people are exposed to the building, its structural integrity is of great importance considering the safety of its occupants (Raghu, 2013). But how can the structural integrity of a building be monitored efficiently and effectively. This is where the fourth industrial revolution step in, and with minimal human interaction, data can be collected, analysed, and stored, which could also give an indication of any inconsistencies found in the data collected, this is where the Fibre Bragg Grating (FBG) monitoring system is introduced. This paper illustrates how data can be collected and converted to develop stress – strain behaviour and to produce bending moment diagrams for the utilisation and prediction of the structure’s integrity. Embedded fibre optic sensors were used in this study– fibre Bragg grating sensors in particular. The procedure entailed making use of the shift in wavelength demodulation technique and an inscription process of the phase mask technique. The fibre optic sensors considered in this report were photosensitive and embedded in the slab and beams for data collection and analysis. Two sets of fibre cables have been inserted, one purposely to collect temperature recordings and the other to collect strain and temperature. The data was collected over a time period and analysed used to produce bending moment diagrams to make predictions of the structure’s integrity. The data indicated the fibre Bragg grating sensing system proved to be useful and can be used for structural health monitoring in any environment. From the experimental data for the slab and beams, the moments were found to be64.33 kN.m, 64.35 kN.m and 45.20 kN.m (from the experimental bending moment diagram), and as per the idealistic (Ultimate Limit State), the data of 133 kN.m and 226.2 kN.m were obtained. The difference in values gave room for an early warning system, in other words, a reserve capacity of approximately 50% to failure.

Keywords: fibre bragg grating, structural health monitoring, fibre optic sensors, beams

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4487 The Contribution of Buddhist-Based Mindfulness Practices on Ethical Leadership: A Qualitative Study of Organizational Leaders in Thailand

Authors: Kunkanit Sutamchai, Kate E. Rowlands

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Recent public ethical scandals in many organizations around the world have raised concern about organizational ethics, which have, in turn, made ethical behaviors and conducts on the part of leaders become more critical topics in organizational studies. However, current research on the benefits of mindfulness within the workplace contexts has predominantly focused on stress reduction and work performance enhancement, while the aspects of ethical behavior development have been far less investigated in mindfulness research in the organizational and management fields. Only recently has there been an emerging call for organizational researchers and practitioners to study mindfulness concepts and practices from the original Buddhist perspectives given that ethics is regarded as a foundation for Buddhist mindfulness. Yet little, if any, empirical research on the contributions of mindfulness practices to ethical leadership has been done in Eastern Buddhist contexts. Therefore, this study aims to explore the extent to which and how Buddhist-based mindfulness practices can influence organizational leaders’ ethical values and practices. On this basis, Thailand was selected as a context of study due to a predominantly Buddhist society and culture. Qualitative data were gathered through in-depth semi-structured interviews with twenty executive leaders from various private organizations in Thailand, who practice Buddhist-based mindfulness meditation regularly. The findings from this study shed light on the role Buddhist-based mindfulness practices can play in promoting ethical behavior among executive leaders in Thailand. The results also suggest that ethical values and practices influenced by Buddhist-based mindfulness practices are well aligned with the elements appeared in the inter-disciplinary and cross-cultural ethical leadership framework, namely: humane, justice, sustainability and responsibility, and moderation. This study concludes that the integration of ethical dimensions to mindfulness practices may provide promising opportunities for ethical leadership development, particularly in the context of Thailand. This could contribute significantly to the future development of both organizations and society at large. The study also suggests that mindfulness interventions in organizational contexts should place more explicit emphasis on ethics. This may be done by relating the ethical principles underlying Buddhist-based mindfulness to other ethical systems in different contexts and cultures where they can be aligned.

Keywords: Buddhism, ethical leadership, leadership development, mindfulness, Thailand, training

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4486 The Effects of Climate Change and Upstream Dam Development on Sediment Distribution in the Vietnamese Mekong Delta

Authors: Trieu Anh Ngoc, Nguyen Quang Kim

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Located at the downstream of the Mekong Delta, the Vietnamese Mekong Delta is well-known as 'rice bowl' of Vietnam. The Vietnamese Mekong Delta experiences widespread flooding annually where is habitat for about 17 million people. The economy of this region mainly depends on the agricultural productivities. The suspended sediment load in the Mekong River plays an important role in carrying contaminants and nutrients to the delta and changing the geomorphology of the delta river system. In many past decades, flooding and suspended sediment were considered as indispensable factors in agricultural cultivations. Although flooding in the wet season caused serious inundation in paddy field and affected livelihoods, it is an effective facility for flushing acid and saline to this area - alluvial soil heavily contaminated with acid and salt intrusion. In addition, sediment delivery to this delta contained rich-nutrients distributed and deposited on the fields through flooding process. In recent decades, the changing of flow and sediment transport have been strongly and clearly occurring due to upstream dam development and climate change. However, effects of sediment delivery on agricultural cultivations were less attention. This study investigated the impacts of upstream flow on sediment distribution in the Vietnamese Mekong Delta. Flow fluctuation and sediment distribution were simulated by the Mike 11 model, including hydrodynamics model and advection-dispersion model. Various scenarios were simulated based on anticipated upstream discharges. Our findings indicated that sediment delivery into the Vietnamese Mekong Delta come from not only Tien River but also border of Cambodia floodplains. Sediment distribution in the Vietnamese Mekong Delta is dramatically changed by the distance from the main rivers and the secondary channels. The dam development in the upstream is one of the major factors leading a decrease in sediment discharge as well as sediment deposition. Moreover, sea level rise partially contributed to decrease in sediment transport and change of sediment distribution between upstream and downstream of the Vietnamese Mekong Delta.

Keywords: sediment transport, sea level rise, climate change, Mike Model

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4485 An Investigation into the Potential of Industrial Low Grade Heat in Membrane Distillation for Freshwater Production

Authors: Yehia Manawi, Ahmad Kayvanifard

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Membrane distillation is an emerging technology which has been used to produce freshwater and purify different types of aqueous mixtures. Qatar is an arid country where almost 100% of its freshwater demand is supplied through the energy-intensive thermal desalination process. The country’s need for water has reached an all-time high which stipulates finding an alternative way to augment freshwater without adding any drastic affect to the environment. The objective of this paper was to investigate the potential of using the industrial low grade waste heat to produce freshwater using membrane distillation. The main part of this work was conducting a heat audit on selected Qatari chemical industries to estimate the amounts of freshwater produced if such industrial waste heat were to be recovered. By the end of this work, the main objective was met and the heat audit conducted on the Qatari chemical industries enabled us to estimate both the amounts of waste heat which can be potentially recovered in addition to the amounts of freshwater which can be produced if such waste heat were to be recovered. By the end, the heat audit showed that around 605 Mega Watts of waste heat can be recovered from the studied Qatari chemical industries which resulted in a total daily production of 5078.7 cubic meter of freshwater. This water can be used in a wide variety of applications such as human consumption or industry. The amount of produced freshwater may look small when compared to that produced through thermal desalination plants; however, one must bear in mind that this water comes from waste and can be used to supply water for small cities or remote areas which are not connected to the water grid. The idea of producing freshwater from the two widely-available wastes (thermal rejected brine and waste heat) seems promising as less environmental and economic impacts will be associated with freshwater production which may in the near future augment the conventional way of producing freshwater currently being thermal desalination. This work has shown that low grade waste heat in the chemical industries in Qatar and perhaps the rest of the world can contribute to additional production of freshwater using membrane distillation without significantly adding to the environmental impact.

Keywords: membrane distillation, desalination, heat recovery, environment

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4484 3D Microscopy, Image Processing, and Analysis of Lymphangiogenesis in Biological Models

Authors: Thomas Louis, Irina Primac, Florent Morfoisse, Tania Durre, Silvia Blacher, Agnes Noel

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In vitro and in vivo lymphangiogenesis assays are essential for the identification of potential lymphangiogenic agents and the screening of pharmacological inhibitors. In the present study, we analyse three biological models: in vitro lymphatic endothelial cell spheroids, in vivo ear sponge assay, and in vivo lymph node colonisation by tumour cells. These assays provide suitable 3D models to test pro- and anti-lymphangiogenic factors or drugs. 3D images were acquired by confocal laser scanning and light sheet fluorescence microscopy. Virtual scan microscopy followed by 3D reconstruction by image aligning methods was also used to obtain 3D images of whole large sponge and ganglion samples. 3D reconstruction, image segmentation, skeletonisation, and other image processing algorithms are described. Fixed and time-lapse imaging techniques are used to analyse lymphatic endothelial cell spheroids behaviour. The study of cell spatial distribution in spheroid models enables to detect interactions between cells and to identify invasion hierarchy and guidance patterns. Global measurements such as volume, length, and density of lymphatic vessels are measured in both in vivo models. Branching density and tortuosity evaluation are also proposed to determine structure complexity. Those properties combined with vessel spatial distribution are evaluated in order to determine lymphangiogenesis extent. Lymphatic endothelial cell invasion and lymphangiogenesis were evaluated under various experimental conditions. The comparison of these conditions enables to identify lymphangiogenic agents and to better comprehend their roles in the lymphangiogenesis process. The proposed methodology is validated by its application on the three presented models.

Keywords: 3D image segmentation, 3D image skeletonisation, cell invasion, confocal microscopy, ear sponges, light sheet microscopy, lymph nodes, lymphangiogenesis, spheroids

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4483 Accessible Tourism: A Novel Idea for Promoting Tourism in Nepal

Authors: Pankaj Pradhananga

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Inclusive Tourism is a relatively new topic in Nepal. Though the effort of creating accessible and inclusive tourism has already begun, it is still in its infancy. A major concern for Destination Nepal is the lack of awareness and absence of mandatory law in place to encourage Tourism operating sectors for coming up with accessible Tourism products. Given the number economic and social benefits to may be derived from inclusive tourism, it is a critical time for the tourism industry to understand and develop measures towards inclusivity in the gateway to Himalaya. Nepal was struck with a devastating earthquake on April 25th, 2015 which concurrently left more than 4,000 Nepalese with physical disabilities. Nepal has had to rebuild and is continuing to rebuild a lot of infrastructure and the process of rebuilding should be barrier free and use universal design measures. With universal design in place, this would allow access for minority groups such as people with disabilities and the elderly to the historic monuments in Kathmandu valley. Four Seasons Travel ( 4ST) has been a key player in not only creating accessible tourism experiences in Nepal, but also promoting accessible tourism to other tourism operators. Dr. Scott Rains had worked closely with 4ST on accessible tourism. Additionally, it organised an accessible trek which was field tested with a traveler with vision impairment in August 2015. Another accessible trekking experience, in partnership with Washington DC based International Development Institute, was coined as ‘Wounded Heroes Trek to Nepal’, where a group of Veterans that are amputees went trekking in the Annapurna Region. The event made it to the list of UNWTO World Tourism Day celebrations. Such initiatives led by private sector in partnership with various organizations have worked to create a ‘Destination Nepal for all’. However, there is still a lot of work that needs to be done to make Nepal a truly inclusive destination. Partnerships between the private sector and DPOs ( Disabled People’s Organizations) as well as the government are also a sound opportunity for employment creation for people with disabilities. Further, partnerships between the state, tourism service providers and DPOs need to be fostered to create job opportunities for people with disabilities. This can be exemplified through the social Entrepreneurship model with the help of accessible Tourism.

Keywords: accessible tourism, disability, earthquake, inclusion

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4482 Historical Analysis of the Evolution of Swiss Identity and the Successful Integration of Multilingualism into the Swiss Concept of Nationhood

Authors: James Beringer

Abstract:

Switzerland’s ability to forge a strong national identity across linguistic barriers has long been of interest to nationalism scholars. This begs the question of how this has been achieved, given that traditional explanations of luck or exceptionalism appear highly reductionist. This paper evaluates the theory that successful Swiss management of linguistic diversity stems from the strong integration of multilingualism into Swiss national identity. Using archival analysis of Swiss government records, historical accounts of prominent Swiss citizens, as well as secondary literature concerning the fundamental aspects of Swiss national identity, this paper charts the historical evolution of Swiss national identity. It explains how multilingualism was deliberately and successfully integrated into Swiss national identity as a response to political fragmentation along linguistic lines during the First World War. Its primary conclusions are the following. Firstly, the earliest foundations of Swiss national identity were purposefully removed from any association with a single national language. This produced symbols, myths, and values -such as a strong commitment to communalism, the imagery of the Swiss natural landscape, and the use of Latin expressions, which can be adopted across Swiss linguistic groups. Secondly, the First World War triggered a turning point in the evolution of Swiss national identity. The fundamental building blocks proved insufficient in preventing political fractures amongst linguistic lines, as each Swiss linguistic group gravitated towards its linguistic neighbours within Europe. To avoid a repeat of such fragmentation, a deliberate effort was made to fully integrate multilingualism as a fundamental aspect of Swiss national identity. Existing natural symbols, such as the St Gotthard Mountains, were recontextualized in order to become associated with multilingualism. The education system was similarly reformed to reflect the unique multilingual nature of the Swiss nation. The successful result of this process can be readily observed in polls and surveys, with large segments of the Swiss population highlighting multilingualism as a uniquely Swiss characteristic, indicating the symbiotic connection between multilingualism and the Swiss nation.

Keywords: language's role in identity formation, multilingualism in nationalism, national identity formation, Swiss national identity history

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4481 Effects of Kinesio Taping on Postural Stability in Young Soccer Players

Authors: Mustafa Gulsen, Nihan Pekyavas, Emine Atıcı

Abstract:

Purpose: The aim of this study is to investigate the effects of Kinesio taping on postural stability and in young soccer players. Subjects and Methods: 62 volunteered soccer players from Cayyolu Sports Club were included in our study. Permissions were also taken from the club directors about the inclusion of their players to our study. Soccer players between the age of 12 and 16 were included in our study. Players that had previous injury on lower extremities were excluded from the study. Players were randomly divided into two groups: Kinesio taping (KT) (n=31), and control group (n = 31). KT application including gastrocnemius and quadriceps femoris muscle facilitation techniques were applied to the first group. A rest time for 45 minutes was given in order to see the best effectiveness of the tape. The second group was set as the control group and no application was made. All participants were assessed before the application and 45 minutes later. In order to provide the double-blind design of the study, an experienced physiotherapist has done the assessments and another experienced physiotherapist has done the taping. The patients were randomly assigned to one of the two groups using an online random allocation software program. Postural stability was assessed by using Tetrax Interactive Balance System. Thermographic assessment was done by using FLIR E5 (FLIR Systems AB, Sweden) thermal camera in order to see which muscles have the most thermal activity while maintaining postural stability. Results: Statistically significant differences were found in all assessment parameters in both Kinesio Taping and control groups (all p<0.05) except thermal imaging of dominant gastrocnemius muscle results (p=0.668) (Table 1). In comparison of the two groups, statistically significant differences were found in all parameters (all p<0.05). Conclusion: In this study, we investigated the effects of Kinesio taping on postural stability in young soccer players and found that KT application on Quadriceps and Gastrocnemius muscles may have decreased the risk of falling more than the control group. According to thermal imaging assessments, both Quadriceps and Gastrocnemius muscles may be active in maintaining postural stability but in KT group, the temperature of these muscles are higher which leads us to think that they are more activated.

Keywords: Kinesio taping, fall risk, muscle temperature, postural stability

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4480 E-Government Development in Nigeria, 'Bank Verification No': An Anti-Corruption Tool

Authors: Ernest C. Nwadinobi, Amanda Peart, Carl Adams

Abstract:

The leading countries like the USA, UK and some of the European countries have moved their focus away from just developing the e-government platform towards just the electronic services which aim at providing access to information to its citizens or customers, but they have gone to make significant backroom changes that can accommodate this electronic service being provided to its customers or citizens. E-government has moved from just providing electronic information to citizens and customers alike to serving their needs. In developing countries like Nigeria, the enablement of e-government is being used as an anti-corruption tool. The introduction of the Bank verification number (BVN) scheme by the Central Bank of Nigeria, has helped the government in not just saving money but also protecting customer’s transaction and enhancing confidence in the banking sector. This has helped curtail the high rate of cyber and financial crime that has been part of the system. The use of BVN as an anti-corruption tool in Nigeria came at a time there was need for openness, accountability, and discipline, after years of robbing the treasury and recklessness in handling finances. As there has not been a defined method for measuring the strength or success of e-government development, in this case BVN, in Nigeria, progress will remain at the same level. The implementation strategy of the BVN in Nigeria has mostly been a quick fix, quick win solution. In fact, there is little or no indication to show evidence of a framework for e-government. Like other leading countries, there is the need for proper implementation of strategy and framework especially towards a customer orientated process, which will accommodate every administrative body of the government institution including private business rather than focusing on a non-flexible organisational structure. The development of e-government must have a strategy and framework for it to work, and this strategy must enclose every public administration and will not be limited to any individual bodies or organization. A defined framework or monitoring method must be put in place to help evaluate and benchmark government development in e-government. This framework must follow the same concept or principles. In censorious analyses of the existing methods, this paper will denote areas that must be included in the existing approach to be able to channel e-government development towards its defined strategic objectives.

Keywords: Bank Verification No (BVN), quick-fix, anti-corruption, quick-win

Procedia PDF Downloads 147
4479 A Differential Detection Method for Chip-Scale Spin-Exchange Relaxation Free Atomic Magnetometer

Authors: Yi Zhang, Yuan Tian, Jiehua Chen, Sihong Gu

Abstract:

Chip-scale spin-exchange relaxation free (SERF) atomic magnetometer makes use of millimeter-scale vapor cells micro-fabricated by Micro-electromechanical Systems (MEMS) technique and SERF mechanism, resulting in the characteristics of high spatial resolution and high sensitivity. It is useful for biomagnetic imaging including magnetoencephalography and magnetocardiography. In a prevailing scheme, circularly polarized on-resonance laser beam is adapted for both pumping and probing the atomic polarization. And the magnetic-field-sensitive signal is extracted by transmission laser intensity enhancement as a result of atomic polarization increase on zero field level crossing resonance. The scheme is very suitable for integration, however, the laser amplitude modulation (AM) noise and laser frequency modulation to amplitude modulation (FM-AM) noise is superimposed on the photon shot noise reducing the signal to noise ratio (SNR). To suppress AM and FM-AM noise the paper puts forward a novel scheme which adopts circularly polarized on-resonance light pumping and linearly polarized frequency-detuning laser probing. The transmission beam is divided into transmission and reflection beams by a polarization analyzer, the angle between the analyzer's transmission polarization axis and frequency-detuning laser polarization direction is set to 45°. The magnetic-field-sensitive signal is extracted by polarization rotation enhancement of frequency-detuning laser which induces two beams intensity difference increase as the atomic polarization increases. Therefore, AM and FM-AM noise in two beams are common-mode and can be almost entirely canceled by differential detection. We have carried out an experiment to study our scheme. The experiment reveals that the noise in the differential signal is obviously smaller than that in each beam. The scheme is promising to be applied for developing more sensitive chip-scale magnetometer.

Keywords: atomic magnetometer, chip scale, differential detection, spin-exchange relaxation free

Procedia PDF Downloads 159
4478 Curriculum System Optimization under Outstanding Engineers Training Mode of Mechanical and Electronic Engineering

Authors: El Miloudi Djelloul

Abstract:

Teaching program of `A plan for educating and training outstanding engineers' is divided into intramural teaching program and enterprise practice teaching program. Based on analyzing the basic principles of teaching plans which teaching plan follows for undergraduate mechanical and electrical engineering, major contents of specialty teaching project are studied amply. The study contents include the system optimization and reform of common curriculum, specialty curriculum and practice curriculum. The practice indicated that under outstanding engineers training mode, the optimized curriculum system have practicability, and achieve the training objectives.

Keywords: curriculum system, mechanical and electronic engineering, outstanding engineers, teaching program

Procedia PDF Downloads 504
4477 Modelling and Simulation of Aero-Elastic Vibrations Using System Dynamic Approach

Authors: Cosmas Pandit Pagwiwoko, Ammar Khaled Abdelaziz Abdelsamia

Abstract:

Flutter as a phenomenon of flow-induced and self-excited vibration has to be recognized considering its harmful effect on the structure especially in a stage of aircraft design. This phenomenon is also important for a wind energy harvester based on the fluttering surface due to its effective operational velocity range. This multi-physics occurrence can be presented by two governing equations in both fluid and structure simultaneously in respecting certain boundary conditions on the surface of the body. In this work, the equations are resolved separately by two distinct solvers, one-time step of each domain. The modelling and simulation of this flow-structure interaction in ANSYS show the effectiveness of this loosely coupled method in representing flutter phenomenon however the process is time-consuming for design purposes. Therefore, another technique using the same weak coupled aero-structure is proposed by using system dynamics approach. In this technique, the aerodynamic forces were calculated using singularity function for a range of frequencies and certain natural mode shapes are transformed into time domain by employing an approximation model of fraction rational function in Laplace variable. The representation of structure in a multi-degree-of-freedom coupled with a transfer function of aerodynamic forces can then be simulated in time domain on a block-diagram platform such as Simulink MATLAB. The dynamic response of flutter at certain velocity can be evaluated with another established flutter calculation in frequency domain k-method. In this method, a parameter of artificial structural damping is inserted in the equation of motion to assure the energy balance of flow and vibrating structure. The simulation in time domain is particularly interested as it enables to apply the structural non-linear factors accurately. Experimental tests on a fluttering airfoil in the wind tunnel are also conducted to validate the method.

Keywords: flutter, flow-induced vibration, flow-structure interaction, non-linear structure

Procedia PDF Downloads 295
4476 The Effect of General Data Protection Regulation on South Asian Data Protection Laws

Authors: Sumedha Ganjoo, Santosh Goswami

Abstract:

The rising reliance on technology places national security at the forefront of 21st-century issues. It complicates the efforts of emerging and developed countries to combat cyber threats and increases the inherent risk factors connected with technology. The inability to preserve data securely might have devastating repercussions on a massive scale. Consequently, it is vital to establish national, regional, and global data protection rules and regulations that penalise individuals who participate in immoral technology usage and exploit the inherent vulnerabilities of technology. This study paper seeks to analyse GDPR-inspired Bills in the South Asian Region and determine their suitability for the development of a worldwide data protection framework, considering that Asian countries are much more diversified than European ones. In light of this context, the objectives of this paper are to identify GDPR-inspired Bills in the South Asian Region, identify their similarities and differences, as well as the obstacles to developing a regional-level data protection mechanism, thereby satisfying the need to develop a global-level mechanism. Due to the qualitative character of this study, the researcher did a comprehensive literature review of prior research papers, journal articles, survey reports, and government publications on the aforementioned topics. Taking into consideration the survey results, the researcher conducted a critical analysis of the significant parameters highlighted in the literature study. Many nations in the South Asian area are in the process of revising their present data protection measures in accordance with GDPR, according to the primary results of this study. Consideration is given to the data protection laws of Thailand, Malaysia, China, and Japan. Significant parallels and differences in comparison to GDPR have been discussed in detail. The conclusion of the research analyses the development of various data protection legislation regimes in South Asia.

Keywords: data privacy, GDPR, Asia, data protection laws

Procedia PDF Downloads 69
4475 Performance Improvement of Long-Reach Optical Access Systems Using Hybrid Optical Amplifiers

Authors: Shreyas Srinivas Rangan, Jurgis Porins

Abstract:

The internet traffic has increased exponentially due to the high demand for data rates by the users, and the constantly increasing metro networks and access networks are focused on improving the maximum transmit distance of the long-reach optical networks. One of the common methods to improve the maximum transmit distance of the long-reach optical networks at the component level is to use broadband optical amplifiers. The Erbium Doped Fiber Amplifier (EDFA) provides high amplification with low noise figure but due to the characteristics of EDFA, its operation is limited to C-band and L-band. In contrast, the Raman amplifier exhibits a wide amplification spectrum, and negative noise figure values can be achieved. To obtain such results, high powered pumping sources are required. Operating Raman amplifiers with such high-powered optical sources may cause fire hazards and it may damage the optical system. In this paper, we implement a hybrid optical amplifier configuration. EDFA and Raman amplifiers are used in this hybrid setup to combine the advantages of both EDFA and Raman amplifiers to improve the reach of the system. Using this setup, we analyze the maximum transmit distance of the network by obtaining a correlation diagram between the length of the single-mode fiber (SMF) and the Bit Error Rate (BER). This hybrid amplifier configuration is implemented in a Wavelength Division Multiplexing (WDM) system with a BER of 10⁻⁹ by using NRZ modulation format, and the gain uniformity noise ratio (signal-to-noise ratio (SNR)), the efficiency of the pumping source, and the optical signal gain efficiency of the amplifier are studied experimentally in a mathematical modelling environment. Numerical simulations were implemented in RSoft OptSim simulation software based on the nonlinear Schrödinger equation using the Split-Step method, the Fourier transform, and the Monte Carlo method for estimating BER.

Keywords: Raman amplifier, erbium doped fibre amplifier, bit error rate, hybrid optical amplifiers

Procedia PDF Downloads 50
4474 Local Farmer’s Perception on the Role of Room for the River in Livelihoods: Case Study in An Phu District, An Giang Province, Vietnam

Authors: Hoang Vo Thi Minh, Duyen Nguyen Thi Phuong, Gerardo Van Halsema

Abstract:

As one of the deltas which is extremely vulnerable to climate change, the Mekong Delta, Vietnam is facing many challenges that need to be addressed in strategic and holistic ways. In this study scope, a strategic delta planning is recently considered as a new vision of Adaptive Delta Management for the Mekong Delta. In Adaptive Delta Management, Room for the Rivers (RftR) has been formulated as a typical innovation, which is currently in need of careful consideration for implementing in the Mekong Delta’s planning process. This study then attempts to investigate the roles and analyze sociological aspects of the RftR as potential strategic 'soft' measure, in upstream of Hau River in An Phu district, An Giang province, especially in terms of its so-called multifunctions. The study applied social science approach embedded with a few qualitative methods including in-depth interviews and questionnaire distribution and conjoint analysis as a quantitative approach. The former mainly aims at gaining the local community’s perceptions about the RftR solution. The latter tries to gain farmers’ willingness to accept (WTA) with regard to their level of preference towards the three selected solutions which are considered as strategic plans for sustainably developing the MD. Qualitative data analysis shows that, farmers perceive RftR as very useful for their livelihoods due to its multifunctions as well as in terms of water management. The quantitative results illustrated that respondents expressed their WTAs on RftR as 84. 240 thousand VND / year. Amongst the three solutions that are analysed within this study (Floating rice for upper delta, Room for the Rivers for the Middle, and Shrimp-Mangrove integration for the coastal delta), RfrR was ranked as second preference from respondents. This result is not exactly reflecting the real values of these three mentioned solutions but showing a tendency that can be seen as a reference for the decision-makers in delta planning processes.

Keywords: strategic delta planning, room for the River, farmers’ perception, willingness-to-accept, local livelihoods

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4473 Characterization of a Putative Type 1 Toxin-Antitoxin System in Shigella Flexneri

Authors: David Sarpong, Waleed Khursheed, Ernest Danquah, Erin Murphy

Abstract:

Shigella is a pathogenic bacterium responsible for shigellosis, a severe diarrheal disease that claims the lives of immunocompromised individuals worldwide. To develop therapeutics against this disease, an understanding of the molecular mechanisms underlying the pathogen’s physiology is crucial. Small non-coding RNAs (sRNAs) have emerged as important regulators of bacterial physiology, including as components of toxin-antitoxin systems. In this study, we investigated the role of RyfA in S. flexneri physiology and virulence. RyfA, originally identified as an sRNA in Escherichia coli, is conserved within the Enterobacteriaceae family, including Shigella. Whereas two copies of ryfA are present in S. dysenteriae, all other Shigella species contain only one copy of the gene. Additionally, we identified a putative open reading frame within the RyfA transcript, suggesting that it may be a dual-functioning gene encoding a small protein in addition to its sRNA function. To study ryfA in vitro, we cloned the gene into an inducible plasmid and observed the effect on bacterial growth. Here, we report that RyfA production inhibits the growth of S. flexneri, and this inhibition is dependent on the contained open reading frame. In-silico analyses have revealed the presence of two divergently transcribed sRNAs, RyfB1 and RyfB2, which share nucleotide complementarity with RyfA and thus are predicted to function as anti-toxins. Our data demonstrate that RyfB2 has a stronger antitoxin effect than RyfB1. This regulatory pattern suggests a novel form of a toxin-antitoxin system in which the activity of a single toxin is inhibited to varying degrees by two sRNA antitoxins. Studies are ongoing to investigate the regulatory mechanism(s) of the antitoxin genes, as well as the downstream targets and mechanism of growth inhibition by the RyfA toxin. This study offers distinct insights into the regulatory mechanisms underlying Shigella physiology and may inform the development of new anti-Shigella therapeutics.

Keywords: sRNA, shigella, toxin-antitoxin, Type 1 toxin antitoxin

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4472 Cyclic Stress and Masing Behaviour of Modified 9Cr-1Mo at RT and 300 °C

Authors: Preeti Verma, P. Chellapandi, N.C. Santhi Srinivas, Vakil Singh

Abstract:

Modified 9Cr-1Mo steel is widely used for structural components like heat exchangers, pressure vessels and steam generator in the nuclear reactors. It is also found to be a candidate material for future metallic fuel sodium cooled fast breeder reactor because of its high thermal conductivity, lower thermal expansion coefficient, micro structural stability, high irradiation void swelling resistance and higher resistance to stress corrosion cracking in water-steam systems compared to austenitic stainless steels. The components of steam generators that operate at elevated temperatures are often subjected to repeated thermal stresses as a result of temperature gradients which occur on heating and cooling during start-ups and shutdowns or during variations in operating conditions of a reactor. These transient thermal stresses give rise to LCF damage. In the present investigation strain controlled low cycle fatigue tests were conducted at room temperature and 300 °C in normalized and tempered condition using total strain amplitudes in the range from ±0.25% to ±0.5% at strain rate of 10-2 s-1. Cyclic Stress response at high strain amplitudes (±0.31% to ±0.5%) showed initial softening followed by hardening upto a few cycles and subsequent softening till failure. The extent of softening increased with increase in strain amplitude and temperature. Depends on the strain amplitude of the test the stress strain hysteresis loops displayed Masing behaviour at higher strain amplitudes and non-Masing at lower strain amplitudes at both the temperatures. It is quite opposite to the usual Masing and Non-Masing behaviour reported earlier for different materials. Low cycle fatigue damage was evaluated in terms of plastic strain and plastic strain energy approach at room temperature and 300 °C. It was observed that the plastic strain energy approach was found to be more closely matches with the experimental fatigue lives particularly, at 300 °C where dynamic strain aging was observed.

Keywords: Modified 9Cr-mo steel, low cycle fatigue, Masing behavior, cyclic softening

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4471 Investigation of the Heavy Metal Pollution of the River Ecosystems in the Lake Sevan Basin, Armenia

Authors: G. Gevorgyan, S. Khudaverdyan, A. Vaseashta

Abstract:

The Lake Sevan basin is situated in the eastern part of the Republic of Armenia (Gegharquniq marz/district). The heavy metal pollution of the some tributaries of Lake Sevan was investigated. Water sampling was performed in August and December, 2014 from the 4 observation sites: 1) Sotq river upstream (about 600 meters upstream from the Sotq gold mine); 2) Sotq river mouth; 3) Masrik river mouth; 4) Dzknaget river mouth. Heavy metal (V, Fe, Ni, Cu, As, Mo, Pb) concentrations in the water samples were determined by the standard methods using an atomic absorption spectrophotometer. The results of the study showed that heavy metal content mainly increased from the upstream of the Sotq river to the mouth of the Masrik river which may have been conditioned by the influence of gold mining activity as the Masrik and its tributary-Sotq rivers passing through the gold mining area were exposed to heavy metal pollution. The observation sites can be ranked by pollution degree as follows: №3> №2> №1> №4. The highest heavy metal pollution degree was observed in the Masrik river mouth which may have been conditioned by the direct impact of gold mining activity and the pressure of its tributary–the Sotq river which flows through the gold mining area. The lowest heavy metal pollution degree was registered in the Dzknaget river mouth which flowing through rural areas wasn’t subject to significant heavy metal pollution. According to the observation sites of the Sotq and Masrik rivers, high positive correlation was mainly observed between the concentrations of the investigated heavy metals (except nickel) which indicated that all the heavy metals except the nickel had the same anthropogenic pollution source which was the activity of the Sotq gold mine. In general, it is possible to state that the activity of the Sotq gold mine in the Lake Sevan basin caused the heavy metal pollution of the Sotq and Masrik rivers which may have posed environmental hazards. Heavy metals are nondegradable substances, and heavy metal pollution of freshwater systems may pose risks to the environment and human health through accumulation in the tissues of aquatic organisms, water-food chain as well as oral ingestion and dermal contact.

Keywords: Armenia, Lake Sevan basin, gold mining activity, river ecosystems, heavy metal pollution

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4470 Effects of Machining Parameters on the Surface Roughness and Vibration of the Milling Tool

Authors: Yung C. Lin, Kung D. Wu, Wei C. Shih, Jui P. Hung

Abstract:

High speed and high precision machining have become the most important technology in manufacturing industry. The surface roughness of high precision components is regarded as the important characteristics of the product quality. However, machining chatter could damage the machined surface and restricts the process efficiency. Therefore, selection of the appropriate cutting conditions is of importance to prevent the occurrence of chatter. In addition, vibration of the spindle tool also affects the surface quality, which implies the surface precision can be controlled by monitoring the vibration of the spindle tool. Based on this concept, this study was aimed to investigate the influence of the machining conditions on the surface roughness and the vibration of the spindle tool. To this end, a series of machining tests were conducted on aluminum alloy. In tests, the vibration of the spindle tool was measured by using the acceleration sensors. The surface roughness of the machined parts was examined using white light interferometer. The response surface methodology (RSM) was employed to establish the mathematical models for predicting surface finish and tool vibration, respectively. The correlation between the surface roughness and spindle tool vibration was also analyzed by ANOVA analysis. According to the machining tests, machined surface with or without chattering was marked on the lobes diagram as the verification of the machining conditions. Using multivariable regression analysis, the mathematical models for predicting the surface roughness and tool vibrations were developed based on the machining parameters, cutting depth (a), feed rate (f) and spindle speed (s). The predicted roughness is shown to agree well with the measured roughness, an average percentage of errors of 10%. The average percentage of errors of the tool vibrations between the measurements and the predictions of mathematical model is about 7.39%. In addition, the tool vibration under various machining conditions has been found to have a positive influence on the surface roughness (r=0.78). As a conclusion from current results, the mathematical models were successfully developed for the predictions of the surface roughness and vibration level of the spindle tool under different cutting condition, which can help to select appropriate cutting parameters and to monitor the machining conditions to achieve high surface quality in milling operation.

Keywords: machining parameters, machining stability, regression analysis, surface roughness

Procedia PDF Downloads 216
4469 The Dependency of the Solar Based Disinfection on the Microbial Quality of the Source Water

Authors: M. T. Amina, A. A. Alazba, U. Manzoor

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Solar disinfection (SODIS) is a viable method for household water treatment and is recommended by the World Health Organization as cost effective approach that can be used without special skills. The efficiency of both SODIS and solar collector disinfection (SOCODIS) system was evaluated using four different sources of water including stored rainwater, storm water, ground water and treated sewage. Samples with naturally occurring microorganisms were exposed to sunlight for about 8-9 hours in 2-L polyethylene terephthalate bottles under similar experimental conditions. Total coliform (TC), Escherichia coli (E. coli) and heterotrophic plate counts (HPC) were used as microbial water quality indicators for evaluating the disinfection efficiency at different sunlight intensities categorized as weak, mild and strong weathers. Heterotrophic bacteria showed lower inactivation rates compared to E. coli and TC in both SODIS and SOCODIS system. The SOCODIS system at strong weather was the strongest disinfection system in this study and the complete inactivation of HPC was observed after 8-9 hours of exposure with SODIS being ineffective for HPC. At moderate weathers, however, the SOCODIS system did not show complete inactivation of HPC due to very high concentrations (up to 5x10^7 CFU/ml) in both storm water and treated sewage. SODIS even remained ineffective for the complete inactivation of E. coli due to its high concentrations of about 2.5x10^5 in treated sewage compared with other waters even after 8-9 hours of exposure. At weak weather, SODIS was not effective at all while SOCODIS system, though incomplete, showed good disinfection efficiency except for HPC and to some extent for high E. coli concentrations in storm water. Largest reduction of >5 log occurred for TC when used stored rainwater even after 6 hours of exposure in the case of SOCODIS system at strong weather. The lowest E. coli and HPC reduction of ~2 log was observed in SODIS system at weak weather. Further tests with varying pH and turbidity are required to understand the effects of reaction parameters that could be a step forward towards maximizing the disinfection efficiency of such systems for the complete inactivation of naturally occurring E. coli or HPC at moderate or even at weak weathers.

Keywords: efficiency, microbial, SODIS, SOCODIS, weathers

Procedia PDF Downloads 250