Search results for: critical features
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8665

Search results for: critical features

2635 Nanostructured Oxide Layer by Anodization on Austenitic Stainless Steels: Structural and Corrosion Insights

Authors: Surya Prakash Gajagouni, Akram Alfantazi, Imad Barsoum

Abstract:

Austenitic stainless steels are widely recognized for their exceptional corrosion resistance and mechanical properties, rendering them indispensable materials across various industries from construction to biomedical applications. However, in chloride and high temperature atmosphere it to further enhance their surface properties, anodization has emerged as a promising surface treatment technique. Anodization modifies the surface of stainless steels by creating a protective oxide layer, improving corrosion resistance and imparting additional functional characteristics. This paper explores the structural and corrosion characteristics of anodized austenitic stainless steels (AISI 304) using a two-step anodic technique. We utilized a perchloric acid-based electrolyte followed by an ammonium fluoride-based electrolyte. This sequential approach aimed to cultivate deeper and intricately self-ordered nanopore oxide arrays on a substrate made of 304 stainless steel. Electron Microscopic (SEM and TEM) images revealed nanoporous layered structures with increased length and crack development correlating with higher voltage and anodization time. Surface composition and chemical oxidation state of surface-treated SS were determined using X-ray photoelectron spectroscopy (XPS) techniques, revealing a surface layer rich in Ni and suppressed Cr, resulting in a thin film composed of Ni and Fe oxide compared to untreated SS. Electrochemical studies demonstrated enhanced corrosion resistance in a strong alkaline medium compared to untreated SS. Understanding the intricate relationship between the structural features of anodized stainless steels and their corrosion resistance is crucial for optimizing the performance of these materials in diverse applications. This study aims to contribute to the advancement of surface engineering strategies for enhancing the durability and functionality of austenitic stainless steels in aggressive environments.

Keywords: austenitic stainless steel, anodization, nanoporous oxides, marine corrosion

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2634 Foreign Artificial Intelligence Investments and National Security Exceptions in International Investment Law

Authors: Ying Zhu

Abstract:

Recent years have witnessed a boom of foreign investments in the field of artificial intelligence (AI). Foreign investments provide critical capital for AI development but also trigger national security concerns of host states. A notable example is an increasing number of cases in which the Committee on Foreign Investment in the United States (CFIUS) has denied Chinese acquisitions of US technology companies on national security grounds. On July 19, 2018, the Congress has reached a deal on the final draft of a new provision to strengthen CFIUS’s authority to review overseas transactions involving sensitive US technology. The question is: how to reconcile the emerging tension between, on the one hand, foreign AI investors’ expectations of a predictable investment environment, and on the other hand, host states’ regulatory power on national security? This paper provides a methodology to reconcile this tension under international investment law. Based on an examination, the national security exception clauses in international investment treaties and the application of national security justification in investor-state arbitration jurisprudence, the paper argues that a traditional interpretation of the national security exception, based on the necessity concept in customary international law, fails to take into account new risks faced by countries, including security concerns over strategic industries such as AI. To overcome this shortage, the paper proposes to incorporate an integrated national security clause in international investment treaties, which includes a two-tier test: a ‘self-judging’ test in the pre-establishment period and a ‘proportionality’ test in the post-establishment period. At the end, the paper drafts a model national security clause for future treaty-drafting practice.

Keywords: foreign investment, artificial intelligence, international investment law, national security exception

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2633 The Impact of Hospital Intensive Care Unit Window Design on Daylighting and Energy Performance in Desert Climate

Authors: A. Sherif, H. Sabry, A. Elzafarany, M. Gadelhak, R. Arafa, M. Aly

Abstract:

This paper addresses the design of hospital Intensive Care Unit windows for the achievement of visual comfort and energy savings. The aim was to identify the window size and shading system configurations that could fulfill daylighting adequacy, avoid glare and reduce energy consumption. The study focused on addressing the effect of utilizing different shading systems in association with a range of Window-to-Wall Ratios (WWR) in different orientations under the desert clear-sky of Cairo, Egypt. The results of this study demonstrated that solar penetration is a critical concern affecting the design of ICU windows in desert locations, as in Cairo, Egypt. Use of shading systems was found to be essential in providing acceptable daylight performance and energy saving. Careful positioning of the ICU window towards a proper orientation can dramatically improve performance. It was observed that ICU windows facing the north direction enjoyed the widest range of successful window configuration possibilities at different WWRs. ICU windows facing south enjoyed a reasonable number of configuration options as well. By contrast, the ICU windows facing the east orientation had a very limited number of options that provide acceptable performance. These require additional local shading measures at certain times due to glare incidence. Moreover, use of horizontal sun breakers and solar screens to protect the ICU windows proved to be more successful than the other alternatives in a wide range of Window to Wall Ratios. By contrast, the use of light shelves and vertical shading devices seemed questionable.

Keywords: daylighting, desert, energy efficiency, shading

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2632 Factors Responsible for Delays in the Execution of Adequately Funded Construction Projects

Authors: Edoghogho Ogbeifun, Charles Mbohwa, J. H. C. Pretorius

Abstract:

Several research report on the factors responsible for the delays in the completion of construction projects has identified the issue of funding as a critical factor; insufficient funding, low cash-flow or lack of funds. Indeed, adequate funding plays pivotal role in the effective execution of construction projects. In the last twenty years (or so), there has been increase in the funds available for infrastructure development in tertiary institution in Nigeria, especially, through the Tertiary Education Trust Fund. This funding body ensures that there is enough fund for each approved project, which is released in three stages during the life of the construction project. However, a random tour of many of the institutions reveals striking evidence of projects not delivered on schedule, to quality and sometime out rightly abandoned. This suggests, therefore, that there are other latent factors, responsible for project delays, that should be investigated. Thus, this research, a pilot scheme, is aimed at unearthing the possible reasons for the delays being experienced in the execution of construction projects for infrastructure upgrade in public tertiary institutions in Nigeria, funded by Tertiary Education Trust Fund. The multiple site case study of qualitative research was adopted. The respondents were the Directors of Physical Planning and the Directors of Works of four Nigerian Public Universities. The findings reveal that delays can be situated within three entities, namely, the funding body, the institutions and others. Therefore, the emerging factors have been classified as external factors (haven to do with the funding body), internal factors (these concern the operations within the institutions) and general factors. The outcome of this pilot exercise provides useful information to guide the Directors as they interact with the funding body as well as challenges themselves to address the loopholes in their internal operations.

Keywords: delays, external factors, funding, general factors, Internal factors

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2631 Evaluation of the Role of Theatre for Development in Combating Climate Change in South Africa

Authors: Isaiah Phillip Smith, Sam Erevbenagie Usadolo, Pamela Theresa Tancsik

Abstract:

This paper is part of ongoing doctoral research that examines the role of Theatre for Development (TfD) in addressing climate change in the Mosuthu community in Reservoir Hills, Durban, South Africa. The context of the research underscores the pressing challenges facing South Africa, including drought, water shortages, deterioration of land, and civil unrest that require innovative approaches to the mitigation of climate change. TfD, described as a dialogical form of theatre that allows communities to express and contribute to development, emerges as a strategic medium for engaging communities in the process. The research problem focused on the unexamined potential of TfD in promoting community involvement and critical awareness of climate change. The study objectives included assessing the community's understanding of climate change, exploring TfD's potential as a participatory tool, examining its role in community mobilization, and developing recommendations for its effective implementation. A review of relevant literature and preliminary investigations in the research community indicates that TfD is an effective medium for promoting societal transformation and engaging marginalized communities. Through culturally resonant narratives, TfD can instill a deeper understanding of environmental challenges, fostering empathy and motivating behavioural changes. By integrating community voices and cultural elements, TfD serves as a powerful catalyst for promoting climate change awareness and inspiring collective action within the South African context. This research contributes to the global discourse on innovative approaches to climate change awareness and action.

Keywords: TfD, climate change, community involvement, societal transformation, culture

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2630 Instrument Development and Validation for Quality Early Childhood Curriculum in the Malaysian Context

Authors: Sadiah Baharom, Che Nidzam Che Ahmad, Saipol Barin Ramli, Asmayati Yahaya, Sopia Md Yassin

Abstract:

The early childhood care and education (ECCE) in Malaysia aspire to develop children who are intellectually, emotionally, physically and spiritually balanced. This aspiration can only materialise if the early childhood program developed comprehensive and is of high quality comparable to international standards. As such, there is a pressing need to assess the quality of the program in an all-encompassing manner. The overall research project aims at developing a comprehensive and integrated model of high-quality Malaysian ECCE. One of the major objectives of this project is to assess and evaluate the scope and quality of the existing ECCE programs in Malaysia. To this end, a specific aspect of this objective is to develop and validate an instrument to assess and evaluate the ECCE curriculum of the country. Thus this paper describes the development and validation of an instrument to explore the quality of early childhood care and education curriculum currently implemented in the country’s ECCE centres. The generation of the constructs and items were based on a set of criteria mapped against existing ECCE practice, document analyses, expert interviews and panel discussions. The items went through expert validation and were field tested on 597 ECCE teachers. The data obtained went through an exploratory factor analysis to validate the constructs of the instrument followed by reliability studies on internal consistency based on the Cronbach Alpha values. The final set of items for the ECCE curriculum instrument, earmarked for the main study, consists of four constructs namely philosophy and core values, curriculum content, curriculum review and unique features. Each construct consists of between 21 to 3 items with a total of 36 items in all. The reliability coefficients for each construct range from 0.65 to 0.961. These values are within the acceptable limits for a reliable instrument to be used in the main study.

Keywords: early childhood and care education, instrument development, reliability studies, validity studies

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2629 Jordanian Health Care Providers' Attitudes toward Overweigth and Obese Women during Childbirth

Authors: Salwa Obeisat

Abstract:

Obesity had become a global issue and a major public health concern, because of its impact on the public health. Obstetric and midwifery evidences reported that maternal obesity an important issue, because of its associated complications like obstructed labors, infections, and hemorrhage. People who are obese are often stigmatized and blamed for their weight. Health care providers are not immune to obesity-related prejudice, and the literature features several examples of their negative attitudes towards obese patients. In Jordan, few studies were conducted to investigate obesity prevalence rate and its associated factors. The purposes of this study were to assess the health care providers' attitudes toward overweight and obese women during the childbirth in the North of Jordan and to investigate the relationships between health care providers' socio-demographic characteristics and their attitudes. A descriptive, cross-sectional design was utilized. A convenient sample was consisted of 95 midwives, 30 nurses and 62 obstetricians, who were working in the labor rooms. A self-administered questionnaire consisted of three sections: demographical data, Arabic version of Fat Phobia Scale (FPS), and Arabic version of Nurses' Attitudes toward Obesity and Obese Patients Scale (NATOOPS). Results: The study findings revealed that the majority of Jordanian health care providers held negative attitudes toward overweight and obese women during childbirth. Midwives held less negative attitudes than did obstetricians and nurses. The majority of participants were perceived the overweight and obese pregnant women during childbirth as overate people, shapeless, slow and unattractive. Age, specialty, education and years of experience were found to be associated with health care providers’ attitudes. The Conclusion: Health care providers negative attitudes toward overweight and obese pregnant women are a cause for concern. Therefore, maternal obesity was needed to be more adequately addressed in basic education courses, and in the continuing professional education classes of practicing health care providers.

Keywords: attitudes, obesity, prevalence rate, nurses, midwives, obstetrician, childbirth

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2628 Effect of Temperature and Deformation Mode on Texture Evolution of AA6061

Authors: M. Ghosh, A. Miroux, L. A. I. Kestens

Abstract:

At molecular or micrometre scale, practically all materials are neither homogeneous nor isotropic. The concept of texture is used to identify the structural features that cause the properties of a material to be anisotropic. For metallic materials, the anisotropy of the mechanical behaviour originates from the crystallographic nature of plastic deformation, and is therefore controlled by the crystallographic texture. Anisotropy in mechanical properties often constitutes a disadvantage in the application of materials, as it is often illustrated by the earing phenomena during drawing. However, advantages may also be attained when considering other properties (e.g. optimization of magnetic behaviour to a specific direction) by controlling texture through thermo-mechanical processing). Nevertheless, in order to have better control over the final properties it is essential to relate texture with materials processing route and subsequently optimise their performance. However, up to date, few studies have been reported about the evolution of texture in 6061 aluminium alloy during warm processing (from room temperature to 250ºC). In present investigation, recrystallized 6061 aluminium alloy samples were subjected to tensile and plane strain compression (PSC) at room and warm temperatures. The gradual change of texture following both deformation modes were measured and discussed. Tensile tests demonstrate the mechanism at low strain while PSC does the same at high strain and eventually simulate the condition of rolling. Cube dominated texture of the initial rolled and recrystallized AA6061 sheets were replaced by domination of S and R components after PSC at room temperature, warm temperature (250ºC) though did not reflect any noticeable deviation from room temperature observation. It was also noticed that temperature has no significant effect on the evolution of grain morphology during PSC. The band contrast map revealed that after 30% deformation the substructure inside the grain is mainly made of series of parallel bands. A tendency for decrease of Cube and increase of Goss was noticed after tensile deformation compared to as-received material. Like PSC, texture does not change after deformation at warm temperature though. n-fibre was noticed for all the three textures from Goss to Cube.

Keywords: AA 6061, deformation, temperature, tensile, PSC, texture

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2627 Procedures and Strategies in Translation: Two Marathi Translations of Train to Pakistan by Khushwant Singh

Authors: Manoj Gujar

Abstract:

The present paper is an attempt to interpret two Marathi translations of Khushwant Singh’s (1915-2014) novel Train to Pakistan (1956). The 20th century was branded as an era of Liberalization, Privatization and Globalization. Different countries and cultures have enunciated interaction with one another in an unprecedented manner. The world is becoming multilingual and multicultural. The democratic countries such as the U.S.A., the U.K., and India have become pivotal centers of interlingual and cross-cultural exchange. People belonging to different nationalities showed keen interest in knowing the characteristic features of different languages and of their cultures. Here, ‘Translation’ plays an important role in such multilingual and multicultural contexts. Translation is not only translation of a language but a translation of a culture. However, in the act of translation a translator makes use of such procedures as borrowing, definition, literal translation, substitution, lexical creation, omission, addition as well as their various combinations. To him, a text produced in one linguistic and cultural context can reach other linguistic and cultural contexts through these processes of translation. A worthy work of art appeals many readers. India, being a multilingual country we find that there goes multiple translations of the same text in different Indian languages. But sometimes, if can be found that a same text appeals to different ages and the same text gets translated into the same language by the two or more authors. In this reference, the present paper is an attempt to study how different translations of the same text differ in terms of procedures and strategies during the process of the translation of culture. The source text is Khushwant Singh’s historical novel Train to Pakistan (1956). The novel was widely appreciated and so translated into different regional languages in India. The novel has two Marathi translations: Agniratha (1972) by Hidayatkhan and Train to Pakistan (1980) by Anil Kinikar. This paper is an attempt to evaluate the strategies and procedures in translation to analyze these two Marathi translations. Hidayat Khan made a lot of omissions of the significant details and distorted the original text to a large extent, whereas, Anil Kinikar has done justice to the Source Text by rendering it in Marathi as faithfully as possible.

Keywords: culture, multilingual, procedures and strategies, translation

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2626 The Influence of Dietary Components on Acne; A Case-Control Survey

Authors: Atiya Mahmood, Mubasharah Hanif, Ghazala Butt, Mehwish Zahoor Ahmed

Abstract:

Acne vulgaris affects millions of adults.Despite extensive research, its food related etiology remains elusive. Objective:To assess the correlation between dietary intake and acne through a case-control survey of 300,15-25 year old respondents living in Pakistan. 50 acne patients and 150 age-and ethnicity-matched controls completed a questionnaire.Cases and controls were separated using SPSS-22 and univariate analysis was performed using the chi-square test. p value < 0.05 was considered statistically significant. We used adjusted odds ratios to assess the strength of associations with 95% confidence intervals. Most of the respondents were females(91.3%).Most(48.7%)acne patients were 20-25 yearsold.Acne severity was mild in 50%,moderate in 34%,severe in14%and very severe in 2%.Frequent low-fat foods(p<0.001)(OR=3.22),fat intake(p=0.03)(OR = 1.629),sweet snacks i.e. biscuits and candies etc. (p=0.013) (OR=1.9254), soft drinks(p= 0.045)(OR= 1.9091),butter(p<0.001) (OR= 1.8185),dairy products(p=0.043)(OR=0.624),salty foods(p= 0.011)(OR=1.961),chocolate (p=0.028)(OR=1.669), were associated with increased acne risk.No association was found with consumption of fried foods, desserts, fruit juices, raw fruit, fast food, vegetables, cheese, soy products, salt, and corn. Increased butter and chocolate consumption were linked to more severe forms of acne(p=0.049 and p=0.005 respectively).Most respondents (n=218) considered themselves to have healthy eating habits, indicating they were not educated about the nutritional aspects of acne treatment.Certain food item intake was significantly higher in acne patients to give an association between the two. Further studies must be conducted to develop a causative relationship. Nutrition aawareness is critical to reduce acne.

Keywords: correlation between dietary components and acne, dietary components, acne, nutrition

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2625 An Extensive Review Of Drought Indices

Authors: Shamsulhaq Amin

Abstract:

Drought can arise from several hydrometeorological phenomena that result in insufficient precipitation, soil moisture, and surface and groundwater flow, leading to conditions that are considerably drier than the usual water content or availability. Drought is often assessed using indices that are associated with meteorological, agricultural, and hydrological phenomena. In order to effectively handle drought disasters, it is essential to accurately determine the kind, intensity, and extent of the drought using drought characterization. This information is critical for managing the drought before, during, and after the rehabilitation process. Over a hundred drought assessments have been created in literature to evaluate drought disasters, encompassing a range of factors and variables. Some models utilise solely hydrometeorological drivers, while others employ remote sensing technology, and some incorporate a combination of both. Comprehending the entire notion of drought and taking into account drought indices along with their calculation processes are crucial for researchers in this discipline. Examining several drought metrics in different studies requires additional time and concentration. Hence, it is crucial to conduct a thorough examination of approaches used in drought indices in order to identify the most straightforward approach to avoid any discrepancies in numerous scientific studies. In case of practical application in real-world, categorizing indices relative to their usage in meteorological, agricultural, and hydrological phenomena might help researchers maximize their efficiency. Users have the ability to explore different indexes at the same time, allowing them to compare the convenience of use and evaluate the benefits and drawbacks of each. Moreover, certain indices exhibit interdependence, which enhances comprehension of their connections and assists in making informed decisions about their suitability in various scenarios. This study provides a comprehensive assessment of various drought indices, analysing their types and computation methodologies in a detailed and systematic manner.

Keywords: drought classification, drought severity, drought indices, agricultur, hydrological

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2624 De Novo Design of Functional Metalloproteins for Biocatalytic Reactions

Authors: Ketaki D. Belsare, Nicholas F. Polizzi, Lior Shtayer, William F. DeGrado

Abstract:

Nature utilizes metalloproteins to perform chemical transformations with activities and selectivities that have long been the inspiration for design principles in synthetic and biological systems. The chemical reactivities of metalloproteins are directly linked to local environment effects produced by the protein matrix around the metal cofactor. A complete understanding of how the protein matrix provides these interactions would allow for the design of functional metalloproteins. The de novo computational design of proteins have been successfully used in design of active sites that bind metals like di-iron, zinc, copper containing cofactors; however, precisely designing active sites that can bind small molecule ligands (e.g., substrates) along with metal cofactors is still a challenge in the field. The de novo computational design of a functional metalloprotein that contains a purposefully designed substrate binding site would allow for precise control of chemical function and reactivity. Our research strategy seeks to elucidate the design features necessary to bind the cofactor protoporphyrin IX (hemin) in close proximity to a substrate binding pocket in a four helix bundle. First- and second-shell interactions are computationally designed to control orientation, electronic structure, and reaction pathway of the cofactor and substrate. The design began with a parameterized helical backbone that positioned a single histidine residue (as an axial ligand) to receive a second-shell H-bond from a Threonine on the neighboring helix. The metallo-cofactor, hemin was then manually placed in the binding site. A structural feature, pi-bulge was introduced to give substrate access to the protoporphyrin IX. These de novo metalloproteins are currently being tested for their activity towards hydroxylation and epoxidation. The de novo designed protein shows hydroxylation of aniline to 4-aminophenol. This study will help provide structural information of utmost importance in understanding de novo computational design variables impacting the functional activities of a protein.

Keywords: metalloproteins, protein design, de novo protein, biocatalysis

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2623 Exploring Challenges Faced by People Living with HIV/AIDS After Disclosure in Sub-Saharan Countries

Authors: Veliswa Nonfundo Hoho, Jabulani Gilford Kheswa

Abstract:

HIV/AIDS has been a long-term condition worldwide, which does not only affect physical health but also causes psychological and social challenges in people living with this condition. In Sub-Saharan countries, namely; Nigeria, Uganda, Zimbabwe and South Africa, people living with HIV/AIDS come across different challenges especially after one has disclosed his/her status. They experience stigma and discrimination, isolation, lack of accessing and receiving treatment, lack of support and experience psychological distress. By using the evidence-based systematic review as a form of methodology, journal articles, dissertations, internet, and books were explored. This paper seeks to describe the challenges faced by people living with HIV/AIDS after disclosure, which forms a critical component of HIV/AIDS prevention and treatment interventions. The disclosure process model is used to underpin the study. This theory allows one to understand when and why interpersonal and verbal self-disclosure is beneficial for individuals who live with concealable stigmatized identities such as HIV/AIDS. Literature findings advocate that both negative and positive results were noted after disclosing one’s HIV status and psychosocial well-being of the majority of people living with HIV/AIDS also get affected especially in societies which subscribe HIV/AIDS pandemic to witchcraft. As for the infected homosexuals, research indicates that they suffer in silence and to cover their emotional emptiness due to ostracism, they often report low- self-efficacy with regard to condom use and become susceptible to reinfections which further place their lives at heightened risk for low immune system. In this regard, this paper challenges the policies which protect the dignity of people living with HIV/AIDS and calls for unity and financial support in favour of psychoeducational programmes and support groups aimed at curbing discrimination.

Keywords: disclosure, discrimination, homosexuality, self-efficacy

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2622 Real-Time Radar Tracking Based on Nonlinear Kalman Filter

Authors: Milca F. Coelho, K. Bousson, Kawser Ahmed

Abstract:

To accurately track an aerospace vehicle in a time-critical situation and in a highly nonlinear environment, is one of the strongest interests within the aerospace community. The tracking is achieved by estimating accurately the state of a moving target, which is composed of a set of variables that can provide a complete status of the system at a given time. One of the main ingredients for a good estimation performance is the use of efficient estimation algorithms. A well-known framework is the Kalman filtering methods, designed for prediction and estimation problems. The success of the Kalman Filter (KF) in engineering applications is mostly due to the Extended Kalman Filter (EKF), which is based on local linearization. Besides its popularity, the EKF presents several limitations. To address these limitations and as a possible solution to tracking problems, this paper proposes the use of the Ensemble Kalman Filter (EnKF). Although the EnKF is being extensively used in the context of weather forecasting and it is being recognized for producing accurate and computationally effective estimation on systems with a very high dimension, it is almost unknown by the tracking community. The EnKF was initially proposed as an attempt to improve the error covariance calculation, which on the classic Kalman Filter is difficult to implement. Also, in the EnKF method the prediction and analysis error covariances have ensemble representations. These ensembles have sizes which limit the number of degrees of freedom, in a way that the filter error covariance calculations are a lot more practical for modest ensemble sizes. In this paper, a realistic simulation of a radar tracking was performed, where the EnKF was applied and compared with the Extended Kalman Filter. The results suggested that the EnKF is a promising tool for tracking applications, offering more advantages in terms of performance.

Keywords: Kalman filter, nonlinear state estimation, optimal tracking, stochastic environment

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2621 Plasma Engineered Nanorough Substrates for Stem Cells in vitro Culture

Authors: Melanie Macgregor-Ramiasa, Isabel Hopp, Patricia Murray, Krasimir Vasilev

Abstract:

Stem cells based therapies are one of the greatest promises of new-age medicine due to their potential to help curing most dreaded conditions such as cancer, diabetes and even auto-immune disease. However, establishing suitable in vitro culture materials allowing to control the fate of stem cells remain a challenge. Amongst the factor influencing stem cell behavior, substrate chemistry and nanotopogaphy are particularly critical. In this work, we used plasma assisted surface modification methods to produce model substrates with tailored nanotopography and controlled chemistry. Three different sizes of gold nanoparticles were bound to amine rich plasma polymer layers to produce homogeneous and gradient surface nanotopographies. The outer chemistry of the substrate was kept constant for all substrates by depositing a thin layer of our patented biocompatible polyoxazoline plasma polymer on top of the nanofeatures. For the first time, protein adsorption and stem cell behaviour (mouse kidney stem cells and mesenchymal stem cells) were evaluated on nanorough plasma deposited polyoxazoline thin films. Compared to other nitrogen rich coatings, polyoxazoline plasma polymer supports the covalent binding of proteins. Moderate surface nanoroughness, in both size and density, triggers cell proliferation. In association with polyoxazoline coating, cell proliferation is further enhanced on nanorough substrates. Results are discussed in term of substrates wetting properties. These findings provide valuable insights on the mechanisms governing the interactions between stem cells and their growth support.

Keywords: nanotopography, stem cells, differentiation, plasma polymer, oxazoline, gold nanoparticles

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2620 A Photographic Look on the Socio-Educational Inclusion of Young Refugees and Asylum-Seekers

Authors: Mara Gabrielli, Jordi Pamies Rovira

Abstract:

From a theoretical and interdisciplinary approach to visual ethnography and visual anthropology, this small scale, in-depth study explores the potential of photography as a participatory ethnographic method for a deep-understanding of the socio-educational integration of young refugees and asylum-seekers in the host society as regards their daily experiences, their needs, desires, expectations, and future goals. Qualitative data is collected by the author by observing 12 young participants in the age group 12-24 years per week for 12 months. The data consists of field notes, participatory observation, in-depth interviews with professionals, and the use of visual participatory ethnographic methods. Therefore, the young participants build their stories through the implementation of two participatory photographic methods - the 'photo-diary' and the 'photo-elicitation' - that permit them to analyse and narrate their social and educational experiences from their perspectives, thus collaborating in the construction of knowledge during the different stages of the research. Preliminary findings show the high resilience and social adaptability of young refugees and asylum-seekers to achieve their goals and overcome structural and socio-cultural barriers. However, the uncertainty of their administrative situation during the asylum submission and the lack of specific resources might impact negatively on their educational pathways and the transition to the labour market. Finally, this study also highlights the benefits of participatory photographic methods in ethnographic research, which impacts positively the well-being of these young people, helps them to develop critical thinking, and it also allows them to access information more respectfully when narrating painful experiences.

Keywords: photo-diary, photo-elicitation, resilience, strategies, visual methodologies, young refugees and asylum seekers

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2619 A Critique of the Neo-Liberal Model of Economic Governance and Its Application to the Electricity Market Industry: Some Lessons and Learning Points from Nigeria

Authors: Kabiru Adamu

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The Nigerian electricity industry was deregulated and privatized in 2005 and 2014 in line with global trend and practice. International and multilateral lending institutions advised developing countries, Nigeria inclusive, to adopt deregulation and privatization as part of reforms in their electricity sectors. The ideological basis of these reforms are traceable to neoliberalism. Neoliberalism is an ideology that believes in the supremacy of free market and strong non-interventionist competition law as against government ownership of the electricity market. This ideology became a state practice and a blue print for the deregulation and privatization of the electricity markets in many parts of the world. The blue print was used as a template for the privatization of the Nigerian electricity industry. In this wise, this paper, using documentary analysis and review of academic literatures, examines neoliberalism as an ideology and model of economic governance for the electricity supply industry in Nigeria. The paper examines the origin of the ideology, it features and principles and how it was used as the blue print in designing policies for electricity reforms in both developed and developing countries. The paper found out that there is gap between the ideology in theory and in practice because although the theory is rational in thinking it is difficult to be implemented in practice. The paper argues that the ideology has a mismatched effect and this has made its application in the electricity industry in many developing countries problematic and unsuccessful. In the case of Nigeria, the article argues that the template is also not working. The article concludes that the electricity sectors in Nigeria have failed to develop into competitive market for the benefit of consumers in line with the assumptions and promises of the ideology. The paper therefore recommends the democratization of the electricity sectors in Nigeria through a new system of public ownership as the solution to the failure of the neoliberal policies; but this requires the design of a more democratic and participatory system of ownership with communities and state governments in charge of the administration, running and operation of the sector.

Keywords: electricity, energy governance, neo-liberalism, regulation

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2618 The Prospect of Income Contingent Loan in Malaysia Higher Education Financing Using Deterministic and Stochastic Methods in Modelling Income

Authors: Syaza Isma, Timothy Higgins

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In Malaysia, increased take-up rates of tertiary student borrowing, and reliance on retirement savings to fund children's education show the importance of public higher education financing schemes (PTPTN). PTPTN has been operating for 2 decades now; however, there are some critical issues and challenges that include low loan recovery and loan default that suggest a detailed consideration of student loan/financing scheme alternatives is crucial. In addition, the decline in funding level per student following introduction of the new PTPTN full and partial loan scheme has raised ongoing concerns over the sustainability of the scheme to provide continuous financial assistance to students in tertiary education. This research seeks to assess these issues that put greater efficiency in an effort to ensure equitable access to student funding for current and future generations. We explore the extent of repayment hardship under the current loan arrangements that presumably led to low recovery from the borrowers, particularly low-income graduates. The concept of manageable debt exists in the design of income-contingent repayment schemes, as practiced in Australia, New Zealand, UK, Hungary, USA (in limited form), the Netherlands, and South Korea. Can Income Contingent Loans (ICL) offer the best practice for an education financing scheme, and address the issue of repayment hardship and concurrently, can a properly designed ICL scheme provide a solution to the current issues and challenges facing Malaysia student financing? We examine the different potential ICL models using deterministic and stochastic approach to simulate income of graduates.

Keywords: deterministic, income contingent loan, repayment burden, simulation, stochastic

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2617 Optimizing Volume Fraction Variation Profile of Bidirectional Functionally Graded Circular Plate under Mechanical Loading to Minimize Its Stresses

Authors: Javad Jamali Khouei, Mohammadreza Khoshravan

Abstract:

Considering that application of functionally graded material is increasing in most industries, it seems necessary to present a methodology for designing optimal profile of structures such as plate under mechanical loading which is highly consumed in industries. Therefore, volume fraction variation profile of functionally graded circular plate which has been considered two-directional is optimized so that stress of structure is minimized. For this purpose, equilibrium equations of two-directional functionally graded circular plate are solved by applying semi analytical-numerical method under mechanical loading and support conditions. By solving equilibrium equations, deflections and stresses are obtained in terms of control variables of volume fraction variation profile. As a result, the problem formula can be defined as an optimization problem by aiming at minimization of critical von-mises stress under constraints of deflections, stress and a physical constraint relating to structure of material. Then, the related problem can be solved with help of one of the metaheuristic algorithms such as genetic algorithm. Results of optimization for the applied model under constraints and loadings and boundary conditions show that functionally graded plate should be graded only in radial direction and there is no need for volume fraction variation of the constituent particles in thickness direction. For validating results, optimal values of the obtained design variables are graphically evaluated.

Keywords: two-directional functionally graded material, single objective optimization, semi analytical-numerical solution, genetic algorithm, graphical solution with contour

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2616 Phase Changing Dicationic Polymeric Ionic Liquid with CO2 Capture Abilities

Authors: Swati Sundararajan, Asit B. Samui, Prashant S. Kulkarni

Abstract:

Polymeric ionic liquids combine the properties of ionic liquids and polymers into a single material which has gained massive interest in the recent years. These ionic liquids offer several advantages such as high phase change enthalpy, wide temperature range, chemical and thermal stability, non-volatility and the ability to make them task-specific. Separation of CO2 is an area of critical importance due to the concerns over greenhouse gasses leading to global warming. Thermal energy storage materials, also known as phase change materials absorb latent heat during fusion process and release the absorbed energy to the surrounding environment during crystallization. These materials retain this property over a number of cycles and therefore, are useful for bridging the gap between energy requirement and use. In an effort to develop materials, which will help in minimizing the growing energy demand and environmental concerns, a series of dicationic poly(ethylene glycol) based polymeric ionic liquids were synthesized. One part of an acrylate of poly(ethylene glycol) was reacted with imidazolium quarternizing agent and the second part was reacted with triazolium quarternizing agent. These two different monomers were then copolymerized to prepare dicationic polymeric ionic liquid. These materials were characterized for solid-liquid phase transition and the enthalpy by using differential scanning calorimetry. The CO2 capture studies were performed on a fabricated setup with varying pressure range from 1-20 atm. The findings regarding the prepared materials, having potential dual applications in the fields of thermal energy storage and CO2 capture, will be discussed in the presentation.

Keywords: CO2 capture, phase change materials, polyethylene glycol, polymeric ionic liquids, thermal energy storage

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2615 Computer-Aided Ship Design Approach for Non-Uniform Rational Basis Spline Based Ship Hull Surface Geometry

Authors: Anu S. Nair, V. Anantha Subramanian

Abstract:

This paper presents a surface development and fairing technique combining the features of a modern computer-aided design tool namely the Non-Uniform Rational Basis Spline (NURBS) with an algorithm to obtain a rapidly faired hull form. Some of the older series based designs give sectional area distribution such as in the Wageningen-Lap Series. Others such as the FORMDATA give more comprehensive offset data points. Nevertheless, this basic data still requires fairing to obtain an acceptable faired hull form. This method uses the input of sectional area distribution as an example and arrives at the faired form. Characteristic section shapes define any general ship hull form in the entrance, parallel mid-body and run regions. The method defines a minimum of control points at each section and using the Golden search method or the bisection method; the section shape converges to the one with the prescribed sectional area with a minimized error in the area fit. The section shapes combine into evolving the faired surface by NURBS and typically takes 20 iterations. The advantage of the method is that it is fast, robust and evolves the faired hull form through minimal iterations. The curvature criterion check for the hull lines shows the evolution of the smooth faired surface. The method is applicable to hull form from any parent series and the evolved form can be evaluated for hydrodynamic performance as is done in more modern design practice. The method can handle complex shape such as that of the bulbous bow. Surface patches developed fit together at their common boundaries with curvature continuity and fairness check. The development is coded in MATLAB and the example illustrates the development of the method. The most important advantage is quick time, the rapid iterative fairing of the hull form.

Keywords: computer-aided design, methodical series, NURBS, ship design

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2614 Game-Theory-Based on Downlink Spectrum Allocation in Two-Tier Networks

Authors: Yu Zhang, Ye Tian, Fang Ye Yixuan Kang

Abstract:

The capacity of conventional cellular networks has reached its upper bound and it can be well handled by introducing femtocells with low-cost and easy-to-deploy. Spectrum interference issue becomes more critical in peace with the value-added multimedia services growing up increasingly in two-tier cellular networks. Spectrum allocation is one of effective methods in interference mitigation technology. This paper proposes a game-theory-based on OFDMA downlink spectrum allocation aiming at reducing co-channel interference in two-tier femtocell networks. The framework is formulated as a non-cooperative game, wherein the femto base stations are players and frequency channels available are strategies. The scheme takes full account of competitive behavior and fairness among stations. In addition, the utility function reflects the interference from the standpoint of channels essentially. This work focuses on co-channel interference and puts forward a negative logarithm interference function on distance weight ratio aiming at suppressing co-channel interference in the same layer network. This scenario is more suitable for actual network deployment and the system possesses high robustness. According to the proposed mechanism, interference exists only when players employ the same channel for data communication. This paper focuses on implementing spectrum allocation in a distributed fashion. Numerical results show that signal to interference and noise ratio can be obviously improved through the spectrum allocation scheme and the users quality of service in downlink can be satisfied. Besides, the average spectrum efficiency in cellular network can be significantly promoted as simulations results shown.

Keywords: femtocell networks, game theory, interference mitigation, spectrum allocation

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2613 Building Safer Communities through Institutional Collaboration in Ghana: An Appraisal of Existing Arrangement

Authors: Louis Kusi Frimpong, Martin Oteng-Ababio

Abstract:

The problem of crime and insecurity in urban environments are often complex, multilayered, multidimensional and sometimes interwoven. It is from this perspective that recent approaches and strategies aimed at responding to crime and insecurity have looked at the problem from a social, economic, spatial and institutional point of view. In Ghana, there is much understanding of how various elements of the social and spatial setting influence crime and safety concerns of residents in urban areas. However, little research attention has been given to the institutional dimension of the problem of crime and insecurity in urban Ghana. In particular, scholars and policymakers in the area of safety and security have scarcely interrogated the forms of collaboration that exist between the various formal and informal institutions and how gaps and lapses in this collaboration influence vulnerability to crime and feelings of insecurity. Using Sekondi-Takoradi as a case study and drawing on both primary and secondary data, this paper assesses the activities of various institutions both formal and informal in crime control and prevention in the Sekondi-Takoradi metropolis, the third largest city in Ghana. More importantly, the paper seeks to address gaps in the institutional arrangement and coordination between and among institutions at the forefront of crime prevention efforts in the metropolis and by extension Ghanaian cities. The study found that whiles there is some form of collaboration between the police and the community, little collaboration existed between planning authorities and the police on the one hand, and the community on the other hand. The paper concludes that in light of the complex nature of a crime, institutional coordination and an inclusive approach involving formal and informal will be critical in promoting safer cities in Ghana.

Keywords: crime prevention, coordination, Ghana, institutional arrangement

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2612 Latinx Adult ELLs: Exploring English Instructors’ Perceptions of Classroom Diversity and Culturally Diverse Teaching Strategies

Authors: Sharon Diaz Ruiz

Abstract:

This qualitative study addresses college English instructors’ perceptions of classroom diversity and culturally diverse teaching strategies within the adult English language learning classroom environment. Every year, English college instructors face numerous challenges as the adult Latinx population keeps rising. To better understand the Latinx adult learners and the language classroom dynamics, research should focus on the experiences, pedagogical methods, and teaching insights of full-time and adjunct minority professors at degree-granting postsecondary institutions. Culturally responsive teaching is used as the framework to understand and explore the perceptions of English instructors on the realities and needs of Latinx adult emergent bilinguals enrolled in developmental English courses. Snowball sampling allows the researcher to locate members who meet these specific criteria: adjunct and part-time English instructors of adult Latinx language learners. Participants answered a demographic questionnaire and then contributed to 45-minute in-depth interviews to explore their perceptions of culturally responsive practices in the Latinx adult emergent bilinguals’ basic and intermediate developmental English courses. The interviews shed light on topics such as teaching biases, educators’ cultural experiences, and resources and strategies faculty recommend for effective culturally responsive teaching strategies. The result of this investigation will shed light on the gap in the literature documenting the application of culturally responsive pedagogy to Latino adult language learners.

Keywords: Latinx, English language learners, English faculty, adult learners, critical theory, culturally responsive theory

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2611 An Introduction to Giulia Annalinda Neglia Viewpoint on Morphology of the Islamic City Using Written Content Analysis Approach

Authors: Mohammad Saber Eslamlou

Abstract:

Morphology of Islamic cities has been extensively studied by researchers of Islamic cities and different theories could be found about it. In this regard, there exist much difference in method of analysis, classification, recognition, confrontation and comparative method of urban morphology. The present paper aims to examine the previous methods, approaches and insights and that how Dr. Giulia Annalinda Neglia dealt with the analysis of morphology of Islamic cities. Neglia is assistant professor in University of Bari, Italy (UNIBA) who has published numerous papers and books on Islamic cities. I introduce her works in the field of morphology of Islamic cities. And then, her thoughts, insights and research methodologies are presented and analyzed in critical perspective. This is a qualitative research on her written works, which have been classified in three major categories. The first category consists mainly of her works on morphology and physical shape of Islamic cities. The results of her works’ review suggest that she has used Moratoria typology in investigating morphology of Islamic cities. Moreover, overall structure of the cities under investigation is often described linear; however, she’s against to define a single framework for the recognition of morphology in Islamic cities. She states that ‘to understand the physical complexity and irregularities in Islamic cities, it is necessary to study the urban fabric by typology method, focusing on transformation processes of the buildings’ form and their surrounding open spaces’ and she believes that fabric of each region in the city follows from the principles of an specific period or urban pattern, in particular, Hellenistic and Roman structures. Furthermore, she believes that it is impossible to understand the morphology of a city without taking into account the obvious and hidden developments associated with it, because form of building and their surrounding open spaces are written history of the city.

Keywords: city, Islamic city, Giulia Annalinda Neglia, morphology

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2610 The Visualization of Hydrological and Hydraulic Models Based on the Platform of Autodesk Civil 3D

Authors: Xiyue Wang, Shaoning Yan

Abstract:

Cities in China today is faced with an increasingly serious river ecological crisis accompanying with the development of urbanization: waterlogging on account of the fragmented urban natural hydrological system; the limited ecological function of the hydrological system caused by a destruction of water system and waterfront ecological environment. Additionally, the eco-hydrological processes of rivers are affected by various environmental factors, which are more complex in the context of urban environment. Therefore, efficient hydrological monitoring and analysis tools, accurate and visual hydrological and hydraulic models are becoming more important basis for decision-makers and an important way for landscape architects to solve urban hydrological problems, formulating sustainable and forward-looking schemes. The study mainly introduces the river and flood analysis model based on the platform of Autodesk Civil 3D. Taking the Luanhe River in Qian'an City of Hebei Province as an example, the 3D models of the landform, river, embankment, shoal, pond, underground stream and other land features were initially built, with which the water transfer simulation analysis, river floodplain analysis, and river ecology analysis were carried out, ultimately the real-time visualized simulation and analysis of rivers in various hypothetical scenarios were realized. Through the establishment of digital hydrological and hydraulic model, the hydraulic data can be accurately and intuitively simulated, which provides basis for rational water system and benign urban ecological system design. Though, the hydrological and hydraulic model based on Autodesk Civil3D own its boundedness: the interaction between the model and other data and software is unfavorable; the huge amount of 3D data and the lack of basic data restrict the accuracy and application range. The hydrological and hydraulic model based on Autodesk Civil3D platform provides more possibility to access convenient and intelligent tool for urban planning and monitoring, a solid basis for further urban research and design.

Keywords: visualization, hydrological and hydraulic model, Autodesk Civil 3D, urban river

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2609 Ontology based Fault Detection and Diagnosis system Querying and Reasoning examples

Authors: Marko Batic, Nikola Tomasevic, Sanja Vranes

Abstract:

One of the strongholds in the ubiquitous efforts related to the energy conservation and energy efficiency improvement is represented by the retrofit of high energy consumers in buildings. In general, HVAC systems represent the highest energy consumers in buildings. However they usually suffer from mal-operation and/or malfunction, causing even higher energy consumption than necessary. Various Fault Detection and Diagnosis (FDD) systems can be successfully employed for this purpose, especially when it comes to the application at a single device/unit level. In the case of more complex systems, where multiple devices are operating in the context of the same building, significant energy efficiency improvements can only be achieved through application of comprehensive FDD systems relying on additional higher level knowledge, such as their geographical location, served area, their intra- and inter- system dependencies etc. This paper presents a comprehensive FDD system that relies on the utilization of common knowledge repository that stores all critical information. The discussed system is deployed as a test-bed platform at the two at Fiumicino and Malpensa airports in Italy. This paper aims at presenting advantages of implementation of the knowledge base through the utilization of ontology and offers improved functionalities of such system through examples of typical queries and reasoning that enable derivation of high level energy conservation measures (ECM). Therefore, key SPARQL queries and SWRL rules, based on the two instantiated airport ontologies, are elaborated. The detection of high level irregularities in the operation of airport heating/cooling plants is discussed and estimation of energy savings is reported.

Keywords: airport ontology, knowledge management, ontology modeling, reasoning

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2608 MRCP as a Pre-Operative Tool for Predicting Variant Biliary Anatomy in Living Related Liver Donors

Authors: Awais Ahmed, Atif Rana, Haseeb Zia, Maham Jahangir, Rashed Nazir, Faisal Dar

Abstract:

Purpose: Biliary complications represent the most common cause of morbidity in living related liver donor transplantation and detailed preoperative evaluation of biliary anatomic variants is crucial for safe patient selection and improved surgical outcomes. Purpose of this study is to determine the accuracy of preoperative MRCP in predicting biliary variations when compared to intraoperative cholangiography in living related liver donors. Materials and Methods: From 44 potential donors, 40 consecutive living related liver donors (13 females and 28 males) underwent donor hepatectomy at our centre from April 2012 to August 2013. MRCP and IOC of all patients were retrospectively reviewed separately by two radiologists and a transplant surgeon.MRCP was performed on 1.5 Tesla MR magnets using breath-hold heavily T2 weighted radial slab technique. One patient was excluded due to suboptimal MRCP. The accuracy of MRCP for variant biliary anatomy was calculated. Results: MRCP accurately predicted the biliary anatomy in 38 of 39 cases (97 %). Standard biliary anatomy was predicted by MRCP in 25 (64 %) donors (100% sensitivity). Variant biliary anatomy was noted in 14 (36 %) IOCs of which MRCP predicted precise anatomy of 13 variants (93 % sensitivity). The two most common variations were drainage of the RPSD into the LHD (50%) and the triple confluence of the RASD, RPSD and LHD (21%). Conclusion: MRCP is a sensitive imaging tool for precise pre-operative mapping of biliary variations which is critical to surgical decision making in living related liver transplantation.

Keywords: intraoperative cholangiogram, liver transplantation, living related donors, magnetic resonance cholangio-pancreaticogram (MRCP)

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2607 Modelling of a Biomechanical Vertebral System for Seat Ejection in Aircrafts Using Lumped Mass Approach

Authors: R. Unnikrishnan, K. Shankar

Abstract:

In the case of high-speed fighter aircrafts, seat ejection is designed mainly for the safety of the pilot in case of an emergency. Strong windblast due to the high velocity of flight is one main difficulty in clearing the tail of the aircraft. Excessive G-forces generated, immobilizes the pilot from escape. In most of the cases, seats are ejected out of the aircrafts by explosives or by rocket motors attached to the bottom of the seat. Ejection forces are primarily in the vertical direction with the objective of attaining the maximum possible velocity in a specified period of time. The safe ejection parameters are studied to estimate the critical time of ejection for various geometries and velocities of flight. An equivalent analytical 2-dimensional biomechanical model of the human spine has been modelled consisting of vertebrae and intervertebral discs with a lumped mass approach. The 24 vertebrae, which consists of the cervical, thoracic and lumbar regions, in addition to the head mass and the pelvis has been designed as 26 rigid structures and the intervertebral discs are assumed as 25 flexible joint structures. The rigid structures are modelled as mass elements and the flexible joints as spring and damper elements. Here, the motions are restricted only in the mid-sagittal plane to form a 26 degree of freedom system. The equations of motions are derived for translational movement of the spinal column. An ejection force with a linearly increasing acceleration profile is applied as vertical base excitation on to the pelvis. The dynamic vibrational response of each vertebra in time-domain is estimated.

Keywords: biomechanical model, lumped mass, seat ejection, vibrational response

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2606 Work System Design in Productivity for Small and Medium Enterprises: A Systematic Literature Review

Authors: Silipa Halofaki, Devi R. Seenivasagam, Prashant Bijay, Kritin Singh, Rajeshkannan Ananthanarayanan

Abstract:

This comprehensive literature review delves into the effects and applications of work system design on the performance of Small and Medium-sized Enterprises (SMEs). The review process involved three independent reviewers who screened 514 articles through a four-step procedure: removing duplicates, assessing keyword relevance, evaluating abstract content, and thoroughly reviewing full-text articles. Various criteria, such as relevance to the research topic, publication type, study type, language, publication date, and methodological quality, were employed to exclude certain publications. A portion of articles that met the predefined inclusion criteria were included as a result of this systematic literature review. These selected publications underwent data extraction and analysis to compile insights regarding the influence of work system design on SME performance. Additionally, the quality of the included studies was assessed, and the level of confidence in the body of evidence was established. The findings of this review shed light on how work system design impacts SME performance, emphasizing important implications and applications. Furthermore, the review offers suggestions for further research in this critical area and summarizes the current state of knowledge in the field. Understanding the intricate connections between work system design and SME success can enhance operational efficiency, employee engagement, and overall competitiveness for SMEs. This comprehensive examination of the literature contributes significantly to both academic research and practical decision-making for SMEs.

Keywords: literature review, productivity, small and medium sized enterprises-SMEs, work system design

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