Search results for: unethical work behavior

Authors: Alaa I. Arafa, Hemdan O. A. Said. Marwa A. M. Ali

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This paper investigates and evaluates experimentally the structural behavior of high strength concrete (HSC) beams under fire and compares it with that of Normal strength concrete (NSC) beams. The main investigated parameters are: concrete compressive strength (300 or 600 kg/cm²); the concrete cover thickness (3 or 5 cm); the degree of temperature (room temperature or 600 ^oC); the type of cooling (air or water); and the fire exposure time (3 or 5 hours). Test results showed that the concrete compressive strength decreases significantly as the exposure time to fire increases.

Keywords: experimental, fire, high strength concrete beams, monotonic loading

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Authors: Mohd Yusri Ibrahim

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Youth participation in social work is essential in social and community development. Although many studies have been conducted to identify the determinant of youth involvement, few studies were discussed interaction between communication skills and youth participation in volunteerism. This article will discuss a cross-sectional study that was conducted to identify the relationship between communication skills and youth participation in social work. The results were successfully developed an interaction model of communication skills as predictor to participation criteria among youth. Finally, the article was suggested several ways to encourage youth participation in community by developing their communication skill in various stages.

Keywords: youth, participation, communication skill, social work

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Authors: Emily Carrothers

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This research takes a critical look at the development of the social worker subjectivity, particularly in Canada. Through an interrogation of required graduate course texts, this paper explicates the discursive formation, orientation, and maintenance of the social worker subject and the conceptualizations of poverty in graduate social work education. This research aims to advance understandings of power and ideology in social work graduate texts and formations of particular dominant constructions of poverty and social worker subjectivity. Guiding questions for this inquiry include: What are social workers being oriented to? What are social workers being oriented away from? How is poverty theorized, discussed and/or attached to social location in social work education? And, how are social workers implicated in contesting or reinforcing poverty? Using critical discourse analysis, 6 texts were analyzed with a particular focus on ways in which notions of poverty are discursively represented and ways in which notions of the formation of the social worker were approached. This revealed that discursively underpinning social work in anti-oppressive practice (AOP) can work to reify hierarchal structures of power that orient social workers away from structural poverty reduction strategies and towards punitive interactions with those that experience poverty and multiple forms of marginalization. This highlights that the social worker subjectivity is formed in opposition to the client, with graduate texts constructing the social worker as an expert in client’s lives and experiences even more so than the client.

Keywords: Canada, education, social work, subjectivity

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Authors: Laura Petrosyan

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The high and persistent working results are possible when people are interested in the results of the work. Motivation of working may be present as a psychological complicated phenomena, which determines person's behavior in working process. Researchers point out that working motivation is displayed in three correlated conditions. These are interest in outcomes of work, satisfaction with the work, and the third, is the level of devotion of employee. Solution of the problem of effective staff management depends on the development of workers' skills. Despite, above mentioned problem could be solved by the process of finding methods to induce the employees to the effective work. Motivation of the managerial activity aroused not only during the working process, but also before it starts. During education the future manager obtains many professional skills. However, the experience shows, that only professional skills are not enough for the effective work. Presently, one of the global educational problems is the development of motivation in professions. In psychological literature the fact is mentioned, that the motivation can be inside and outside. Outside motivation is active only at short time. Instead, inside motivation can be active during all process of the professional development. Hence, the motivation of managerial activity might be developed during the education. The future manager choose the profession being under some impression of personal qualities. Detection of future manager’s motivation will influence on the development of syllabuses. Moreover, use of the psychological methods could be evolved for preparing motivated managers. Conducted research has been done in the Public Administration Academy of the RA. The aim of research was to discover students' motivation of profession. 102 master students took part in the research from Public Administration Academy. In the research were used the following methods: method of identifying a person's motivation to succeed (T. Elers) and method of studying students’ motivation (T.E. Ilyin). First of the methods designed to explore a person's motivational orientation to get success represented by Hackhausen. The method gives the opportunity to reveal the level of motivation to success. In the second method separated three scales: i) Knowledge achievements, ii) Knowledge of the profession, iii) Get a diploma. The data obtained from these tests gave quantitative data. Aanalyses of our survey results exposes that within master students the high level have the average rates of knowledge achievements. The average rates of knowledge of the profession and geting a diploma not in high level. Furthermore, there are almost equal to each other. In the educational process The student acquiring skills not synthesize with the wield profession. Results show that specialists really view about profession not formulated yet.

Keywords: managerial activity, motivation, psychological complicated phenomena, working process, education the future manager

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Authors: Wang Zhulin, Min Fuhong, Peng Guangya, Wang Yaoda, Cao Yi

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In this paper, a magnetron memristor model based on hyperbolic sine function is presented and the correctness proved by studying the trajectory of its voltage and current phase, and then a memristor chaotic system with the memristor model is presented. The phase trajectories and the bifurcation diagrams and Lyapunov exponent spectrum of the magnetron memristor system are plotted by numerical simulation, and the chaotic evolution with changing the parameters of the system is also given. The paper includes numerical simulations and mathematical model, which confirming that the system, has a wealth of dynamic behavior.

Keywords: memristor, chaotic circuit, dynamical behavior, chaotic system

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Authors: Juan Huang, Hugo Ninanya

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Oil has been used as a source of energy and supply to make materials, such as asphalt or rubber for many years. This is the reason why new technologies have been implemented through time. However, research still needs to continue increasing due to new challenges engineers face every day, just like unconventional reservoirs. Various numerical methodologies have been applied in petroleum engineering as tools in order to optimize the production of reservoirs before drilling a wellbore, although not all of these have the same efficiency when talking about studying fracture propagation. Analytical methods like those based on linear elastic fractures mechanics fail to give a reasonable prediction when simulating fracture propagation in ductile materials whereas numerical methods based on the cohesive zone method (CZM) allow to represent the elastoplastic behavior in a reservoir based on a constitutive model; therefore, predictions in terms of displacements and pressure will be more reliable. In this work, a hydro-geomechanical coupled model of horizontal wells in fractured rock was developed using ABAQUS; both extended element method and cohesive elements were used to represent predefined fractures in a model (2-D). A power law for representing the rheological behavior of fluid (shear-thinning, power index <1) through fractures and leak-off rate permeating to the matrix was considered. Results have been showed in terms of aperture and length of the fracture, pressure within fracture and fluid loss. It was showed a high infiltration rate to the matrix as power index decreases. A sensitivity analysis is conclusively performed to identify the most influential factor of fluid loss.

Keywords: fracture, hydro-geomechanical model, non-Newtonian fluid, numerical analysis, sensitivity analysis

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Authors: Chung-Kwei Wang, Kuo-Ying Lo

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The study is aimed to examine main and moderation effect of Chinese traditional social wisdom ‘Ren-qing Shi-kuon' the adjustment of social worker students during their practicum. Ren-qing Shi-ku as a social wisdom has been emphasized by collective-oriented Chinese society for thousand years. Based on interview and literature review, we operationalized the concept as four factors, including ‘harmonious interaction’, ‘understanding and tolerance’, ‘empathetic communication’ and ‘rule abiding’. We administer the scale to 96 social worker senior students before their summer practicums begins and collect their response on emotion labor, emotional exhaustion, work load, work satisfaction. We also ask their supervisors rated their performance on empathy, interpersonal relationships, performance on practicum and their Ren-qing Shi-ku performance. Results indicated that self-ratings of students on Ren-qing Shi-ku scale are correlated with rating from their supervisors. Students who have higher Ren-qing Shi-ku have better adjustment and higher ratings from their supervisor. Ren-qing Shi-ku also moderate effects of surface acting labor and work load on emotional exhaustion and work satisfaction. However, Ren-qing Shi-ku seems more beneficial under low work load situations. The finding of this study suggested traditional social skill training might be very effective for social service providers in a collective-oriented culture.

Keywords: emotion labor, ren-qing shi-ku, emotional exhaustion, work satisfaction and performance

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Authors: Sayed M. Soleimani, Nader H. Ghareeb, Nourhan H. Shaker, Muhammad B. Siddiqui

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Honeycomb sandwich panels have been widely used as protective structural elements against blast loading. The main advantages of these panels include their light weight due to the presence of voids, as well as their energy absorption capability. Terrorist activities have imposed new challenges to structural engineers to design protective measures for vital structures. Since blast loading is not usually considered in the load combinations during the design process of a structure, researchers around the world have been motivated to study the behavior of potential elements capable of resisting sudden loads imposed by the detonation of explosive materials. One of the best candidates for this objective is the honeycomb sandwich panel. Studying the effects of explosive materials on the panels requires costly and time-consuming experiments. Moreover, these type of experiments need permission from defense organizations which can become a hurdle. As a result, modeling and simulation using an appropriate tool can be considered as a good alternative. In this research work, the finite element package ABAQUS® is used to study the behavior of hexagonal and squared honeycomb steel sandwich panels under the explosive effects of different amounts of trinitrotoluene (TNT). The results of finite element modeling of a specific honeycomb configuration are initially validated by comparing them with the experimental results from literature. Afterwards, several configurations including different geometrical properties of the honeycomb wall are investigated and the results are compared with the original model. Finally, the effectiveness of the core shape and wall thickness are discussed, and conclusions are made.

Keywords: Abaqus, blast loading, finite element modeling, steel honeycomb sandwich panel

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Authors: Cao Yuping, Li Longfei, Zhao Xingfu, Zhang Yalin

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Purpose: This study examined the effects of exposure to domestic physical violence (DPV) on children’s behavior in a community sample. Method: Ninety-three 12-16 year-old adolescents exposed to DPV were matched with 54 adolescents with no exposure to DPV based on age, gender, family composition and parental age and education level. Participation included assessment with the Childhood Trauma Questionnaire (CTQ-SF) and Child Behavior Checklist (CBCL) by the adolescents and their parents respectively. Results: CBCL total score and anxiety/depression, social interaction problems, attention problems, delinquency, aggression and externalizing scores were significantly higher in adolescents exposed to DPV than those in controls (all ps<0.05).The CBCL total score and scores of anxiety/depression, social interaction problems, attention problems, delinquency, aggression and externalizing behaviors of boys were significantly higher in the research group than in the controls (all ps<0.05). Delinquency scores in abused adolescents were significantly higher than in DPV witnessed (p<0.05), but no other scores of CBCL were significant different. Different subtypes of behavioral problems were associated with different types of abuse. Conclusions: DPV exposure is associated with adverse behaviors in children, especially among boys. Children witness DPV alone have similar behavioral scores as the abused children. We recommend that both abused and DPV witness adolescents in Chinese communities need treatment to mitigate the effects on maladjusted behaviors.

Keywords: domestic violence, child, behavior, community, China

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Authors: Amir Hossein Ghaffari Nejad, Forouhar Ferdowsi, Reza Mashhadi

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In the interest-free banking system of Iran, the savings of society are in the form of bank deposits, and banks using the Islamic contracts, allocate the resources to applicants for obtaining facilities and credit. In the meantime, the central bank, with the aim of introducing monetary policy, determines the maximum interest rate on bank deposits in terms of macroeconomic requirements. But in recent years, the country's economic constraints with the stagflation and the consequence of the institutional weaknesses of the financial market of Iran have resulted in massive disturbances in the balance sheet of the banking system, resulting in a period of mismatch maturity in the banks' assets and liabilities and the implementation of a Ponzi game. This issue caused determination of the interest rate in long-term bank deposit contracts to be associated with non-observance of the maximum rate set by the central bank. The result of this condition was in the allocation of new sources of equipment to meet past commitments towards the old depositors and, as a result, a significant part of the supply of equipment was leaked out of the facilitating cycle and credit crunch emerged. The purpose of this study is to identify the most important factors affecting the occurrence of non-confirmatory financial banking behavior using data from 19 public and private banks of Iran. For this purpose, the causes of this non-confirmatory behavior of banks have been investigated using the panel vector autoregression method (PVAR) for the period of 2007-2015. Granger's causality test results suggest that the return of parallel markets for bank deposits, non-performing loans and the high share of the ratio of facilities to banks' deposits are all a cause of the formation of non-confirmatory behavior. Also, according to the results of impulse response functions and variance decomposition, NPL and the ratio of facilities to deposits have the highest long-term effect and also have a high contribution to explaining the changes in banks' non-confirmatory behavior in determining the interest rate on deposits.

Keywords: non-conformity behavior, Ponzi Game, panel vector autoregression, nonperforming loans

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Authors: Iffat Batool

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An extensive body of literature produced by the contemporary Western academia is an indication of their grave interest in the field of Qur’ānic studies. What increases its significance is the writings of the western scholars that underscore the element of objectivity and impartiality in the recent western academic works on the Qur’ān. Moreover, the participation of some Muslim scholars in the western academia is also highlighted by western thinkers to ensure the objectivity of western Qur’ānic scholarship. More specifically, with the publication of ‘Encyclopaedia of the Qur’ān by Brill’ the western academia seems to assign these elements to this work vigorously. Being the foremost work of its nature, ‘Encyclopaedia of the Qur’ān’ has attracted the academicians from across the world yet, with multiple receptions. The present study aims at locating the status of this work in the recent Western scholarship and its contribution towards the subject of Qur’ānic Studies. Through a critical analysis of articles, various features of this work are highlighted. This work concludes that although Encyclopaedia of the Qur’ān presents wide-ranging and extensive study, yet, it lacks a perfect, rigorous and thorough scholarship of the Qur’ān. Besides, this work argues that because of the marginal contribution of Muslim researchers, the majority conclusions of this anthology are in contrast to the traditional Muslim standpoint

Keywords: academic, encyclopeadia, objectivity, quran

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Authors: Martin Popescu D. Dana Maria

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The aims of this research are to broaden the study on the relationship between emotional intelligence and counterproductive work behavior (CWB). The study sample consisted in 441 Romanian employees from companies all over the country. Data has been collected through web surveys and processed with SPSS. The results indicated an average correlation between the two constructs and their sub variables, employees with a high level of emotional intelligence tend to be less aggressive. In addition, labeling was considered an individual difference which has the power to influence the level of employee aggression. A regression model was used to underline the importance of emotional intelligence together with labeling as predictors of CWB. Results have shown that this regression model enforces the assumption that labeling and emotional intelligence, taken together, predict CWB. Employees, who label themselves as victims and have a low degree of emotional intelligence, have a higher level of CWB.

Keywords: aggression, CWB, emotional intelligence, labeling

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Authors: Samantha Clarke

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The term social justice is central to social work; however, the meaning behind this term is not as simple as defining the term itself. This is because the meaning of social justice is relative since its origin and development is based on evolving political perspectives. Political perspectives provide numerous lenses to view social justice in social work; however, the realities of changing society have meant that social justice has assumed different values, definitions, and understandings over time and in different geopolitical and cultural contexts. There are many competing and convincing theories of social justice that are relevant to social work practice. Exploring the term is not an idle preoccupation because the meaning of the term is not as crucial as the meaning of the worldview, as it is the worldview that positions social justice as crucial in the emancipation of people marginalized from oppression. The many political assumptions that underlie the term social justice are explored and connected to the contemporary discussions about social justice in social work. These connections are then interrogated in the Canadian Social Works Code of Ethics, and in micro, mezzo, and macro approaches. To be remiss in interrogating the underlying political assumptions of the worldview of social justice is to entrench oppression and to preserve oppressive structures in contemporary Canadian social work. The concept of social justice is unable to withstand closer scrutiny about its emancipatory qualities in Canadian social work when we interrogate the many political assumptions that frame its understanding. In order to authenticate social justice as an emancipatory central organizing principle, Canadian social workers must engage in deeper discussions about the political implications of social justice in their everyday practices based on diverse worldviews and geopolitical contexts. Social workers are well positioned to develop an understanding of social justice that is emancipatory based on their everyday practices because as social and political actors they are positioned to work for and with individuals and toward the greater good of those who are marginalized from oppression.

Keywords: Canadian social work, political analysis, social justice, social work practice

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Authors: Theo Heyns Veldsman, Dieter Veldsman

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Organisational Identity (OI) refers to who and what the organisation is, what it stands for and does, and what it aspires to become. OI explores the perspectives of how we see ourselves, are seen by others and aspire to be seen. It provides as rationale the ‘why’ for the organisation’s continued existence. The most widely accepted differentiating features of OI are encapsulated in the organisation’s core, distinctive, differentiating, and enduring attributes. OI finds its concrete expression in the organisation’s Purpose, Vision, Strategy, Core Ideology, and Legacy. In the emerging new order infused by hyper-turbulence and hyper-fluidity, the VICCAS world, OI provides a secure anchor and steady reference point for the organisation, particularly the growing widespread focus on Purpose, which is indicative of the organisation’s sense of social citizenship. However, the transforming world of work (TWOW) - particularly the potent mix of ongoing disruptive innovation, the 4th Industrial Revolution, and the gig economy with the totally unpredicted COVID19 pandemic - has resulted in the consequential adoption of different workplace strategies by organisations in terms of how, where, and when work takes place. Different employment relations (transient to permanent); work locations (on-site to remote); work time arrangements (full-time at work to flexible work schedules); and technology enablement (face-to-face to virtual) now form the basis of the employer/employee relationship. The different workplace strategies, fueled by the demands of TWOW, pose a substantive challenge to organisations of doing durable OI work, able to fulfill OI’s critical attributes of core, distinctive, differentiating, and enduring. OI work is contained in the ongoing, reciprocally interdependent stages of sense-breaking, sense-giving, internalisation, enactment, and affirmation. The objective of our paper is to explore how to do durable OI work relative to different workplace strategies in the TWOW. Using a conceptual-theoretical approach from a practice-based orientation, the paper addresses the following topics: distinguishes different workplace strategies based upon a time/place continuum; explicates stage-wise the differential organisational content and process consequences of these strategies for durable OI work; indicates the critical success factors of durable OI work under these differential conditions; recommends guidelines for OI work relative to TWOW; and points out ethical implications of all of the above.

Keywords: organisational identity, workplace strategies, new world of work, durable organisational identity work

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Authors: Dana S. Smith, Angela Goins, Shahnaz Savani

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Using a mixed-methods approach, this study explored costs to student wellbeing generated by the social work field practicum requirement. The project was conducted by faculty at a medium-sized university in the United States. Social work educators and field practicum instructors participated in interviews. Students and former students completed surveys on the topic. The data analysis revealed emotional burdens as well as threats to student wellbeing in association with the fieldwork required for those in pursuit of a social work degree. The study includes recommendations for anti-oppressive approaches for academic programs and implications for further research.

Keywords: emotional wellbeing, field practicum, mixed-methods, social justice

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Authors: Dana S. Smith, Angela Goins, Shahnaz Savani

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Using a mixed-methods approach, this study explored costs to student wellbeing generated by the social work field practicum requirement. The project was conducted by faculty at a medium sized university in the United States. Social work educators and field practicum instructors participated in interviews. Students and former students completed surveys on the topic. The data analysis revealed emotional burdens as well as threats to student wellbeing in association with the fieldwork required for those in pursuit of a social work degree. The study includes recommendations of anti-oppressive approaches for academic programs and implications for further research.

Keywords: emotional wellbeing, field practicum, mixed-methods, social justice

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Authors: Jeongil Kim

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The present study examined the effects of arts-mediated mother-child dyads mindfulness-based intervention for Korean children with attention deficit hyperactivity disorder (ADHD) and their mothers, on behaviors in children and subjective psychological states in mothers. Four elementary school boys with ADHD and their mothers participated in the study. Using a multiple baseline design across four mother-child dyads, data were collected on the target behaviors (disruptive behavior, on-task behavior, and compliance in class) in children using a 10-second partial interval recording system and on the subjective psychological states in mothers using four questionnaires (on perceived stress, burnout, mindfulness, and satisfaction with life). The intervention consisted of a) mindfulness training, b) mindfulness practice, and c) mindful management of body and feeling. The arts activities, making a coiled clay pot and Korean traditional music performance, were utilized to facilitate the environment to help each participant to understand the content and progress of the intervention program. The results showed that all four dyads showed improvement in adaptive behaviors in the children (increase in on-task behavior; decrease in disruptive behavior) and positive change in subjective psychological states in the mothers (increase in scores of mindfulness and satisfaction with life; decrease in scores of perceived stress and burnout). The changes in the children’s behaviors and in the mothers’ subjective psychological states were maintained when the intervention was drawn and generalized in novel settings. The results suggest that arts-mediated mother-child dyads mindfulness-based intervention would be a mutual benefiting strategy to support both children with ADHD and their mothers who experience diverse challenges in behavioral and psychological aspects.

Keywords: mindfulness, attention deficit hyperactivity disorder (ADHD), arts-mediated, behavior, psychological well-being, child-mother

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Authors: B. A. Mir, A. Juneja

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In this paper, shear behavior of reconstituted clay reinforced with varying diameter of sand compaction piles with area replacement-ratio (a_s) of 6.25, 10.24, 16, 20.25 and 64% in 100mm diameter and 200mm long clay specimens is modeled using consolidated drained and undrained triaxial tests under different confining pressures ranging from 50kPa to 575kPa. The test results show that the stress-strain behavior of the clay was highly influenced by the presence of SCP. The insertion of SCPs into soft clay has shown to have a positive effect on the load carrying capacity of the clay, resulting in a composite soil mass that has greater shear strength and improved stiffness compared to the unreinforced clay due to increased reinforcement area ratio. In addition, SCP also acts as vertical drain in the clay thus accelerating the dissipation of excess pore water pressures that are generated during loading by shortening the drainage path and activating radial drainage, thereby reducing post-construction settlement. Thus, sand compaction piles currently stand as one of the most viable and practical techniques for improving the mechanical properties of soft clays.

Keywords: reconstituted clay, SCP, shear strength, stress-strain response, triaxial tests

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Authors: T. Rajamäki

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In clean room environment molecular contamination in very small concentrations can cause significant harm for the components and processes. This is commonly referred as airborne molecular contamination (AMC). There is a shortage of high sensitivity continuous measurement data for existence and behavior of several of these contaminants. Accordingly, in most cases correlation between concentration of harmful molecules and their effect on processes is not known. In addition, the formation and distribution of contaminating molecules are unclear. In this work sensitive optical techniques are applied in clean room facilities for investigation of concentrations, forming mechanisms and effects of contaminating molecules. Special emphasis is on reactive acid and base gases ammonia (NH3) and hydrogen fluoride (HF). They are the key chemicals in several operations taking place in clean room processes.

Keywords: AMC, clean room, concentration, reactive gas

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Authors: Md. Rifad Chowdhury

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This research study investigates employees' conception of work motivation to perform at the municipal corporation in Bangladesh. The municipal corporation is one of the key administrative bodies of Bangladesh’s local government. Municipal corporation employees provide essential public services in the country’s semi-urban areas. Work motivation has been defined as a result of interaction between the individual and the environment. Local government studies indicate the work environment of the municipal corporation is unique because of its key colonial and political history, several reform attempts, non-western social perspectives, job functions, and traditional governance. The explorative purpose of this study is to find and analyse the conceptions of employees’ work motivation within this environment to expand a better understanding of work motivation. According to the purpose of this study, a qualitative method has been adopted, which has remained a very unpopular method among work motivational researchers in Bangladesh. Twenty-two semi-structured online interviews were conducted in this study. Phenomenographic research methodology has been adopted to describe the limited number of qualitatively different ways of experiencing work motivation. During the analysis of the semi-structured interview transcripts, the focus was on the employees' perspectives as employees experience work motivation or the second-order perspective to explore and analyse the conceptions. Based on the participants' collective experiences and dimensions of variation across the different ways of experiencing, six conceptions of employee work motivation to perform at the municipal corporation were identified in this study. The relationships between conceptions were further elaborated in terms of critical variations across the conceptions. Six dimensions of critical variations have emerged within and between the conceptions. In the outcome space, the relationships between conceptions and dimensions of critical variations are presented in a logical structure. The findings of this research study show significance to expand the understanding of work motivation and the research context of phenomenography. The findings of this research will contribute to the ongoing attention of contextual work motivational understanding from a Bangladeshi perspective and phenomenographic research conceptions in organisational behaviour studies.

Keywords: work motivation, qualitative, phenomenography, local government

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Authors: T. N. Mac, B. Shahbodaghkhan, N. Khalili

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A new elastic-viscoplastic (EVP) constitutive model is proposed for the analysis of time-dependent behavior of clay. The proposed model is based on the bounding surface plasticity and the concept of viscoplastic consistency framework to establish continuous transition from plasticity to rate dependent viscoplasticity. Unlike the overstress based models, this model will meet the consistency condition in formulating the constitutive equation for EVP model. The procedure of deriving the constitutive relationship is also presented. Simulation results and comparisons with experimental data are then presented to demonstrate the performance of the model.

Keywords: bounding surface, consistency theory, constitutive model, viscosity

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Authors: Emad K. Jaradat, Ala’a Al-Faqih

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Nonlinear Schrödinger equations are regularly experienced in numerous parts of science and designing. Varieties of analytical methods have been proposed for solving these equations. In this work, we construct an approximate solution for the nonlinear Schrodinger equations, with harmonic oscillator potential, by Elzaki Decomposition Method (EDM). To illustrate the effects of harmonic oscillator on the behavior wave function, nonlinear Schrodinger equation in one and two dimensions is provided. The results show that, it is more perfectly convenient and easy to apply the EDM in one- and two-dimensional Schrodinger equation.

Keywords: non-linear Schrodinger equation, Elzaki decomposition method, harmonic oscillator, one and two-dimensional Schrodinger equation

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Authors: Surendra Kumar Chourasiya, Sandeep Kumar, Devendra Singh

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In the present investigation tribological behavior of Al-6Si-1Mg-1Graphite composite has been explained. The composite was developed through the unique spray forming route in the spray forming chamber by using N₂ gas at 7kg/cm² and the flight distance was 400 mm. Spray formed composite having a certain amount of porosity which was reduced by the deformations. The composite was subjected to the warm rolling (WR) at 250ºC up to 40% reduction. Spray forming composite shows the considerable microstructure refinement, equiaxed grains, distribution of silicon and graphite particles in the primary matrix of the composite. Graphite (Gr) was incorporated externally during the process that works as a solid lubricant. Porosity decreased after reduction and hardness increases. Pin on disc test has been performed to analyze the wear behavior which is the function of sliding distance for all percent reduction of the composite. 30% WR composite shows the better result of wear rate and coefficient of friction. The improved wear properties of the composite containing Gr are discussed in light of the microstructural features of spray formed the composite and the nature of the debris particles. Scanning electron microscope and optical microscope analysis of the present material supported the prediction of aforementioned changes.

Keywords: Al-6Si-1Mg-1Graphite, spray forming, warm rolling, wear

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Authors: Sung-Won Yoo, Chul-Hyeon Kang, Kyoung-Tae Park, Hae-Sik Woo

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Numerous studies were dedicated on the High Volume Fly-Ash (HVFA) concrete using high volume fly ash. The material properties of HVFA concrete have been the primordial topics of early studies, and interest shifted gradually toward the structural behavior of HVFA concrete such as elasticity modulus, stress-strain relationship, and structural behavior. However, structural studies consider small-scale members limited to the scope of reinforced concrete only. Therefore, in this paper, on the basis of recent studies on the structural behavior, 2 full-scale test members were manufactured with 7.5 m span length, fly ash replacement ratio of 50 % and concrete compressive strength of 50 MPa in order to evaluate the practicability of HVFA to real structures. In addition, 2 steel composite test members were also manufactured with span length of 3 m and using the same HVFA concrete for the same purpose. The test results of full-scale RC members showed that the practical use of HVFA on such structures is not hard despite small differences between test results and existing research results on the stress-strain relationship. The flexural test revealed very little difference between 50% fly ash concrete and general concrete in view of the similarity exhibited by the displacement and strain patterns. The experimental concrete shear strength being very close to that of design code, the existing design code can be applied. From the flexural test results of steel girder composite members, the composite behavior can be secured as much as that using normal concrete under the condition of sufficient arrangement of reinforcing bar.

Keywords: composite, fly ash, full-scale, high volume

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Authors: Thammarak Srimarut, Witthaya Mekhum

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This study analysed and developed a model for monk’s food bowl production on occupational health safety and environment at work for the encouragement of Rattanakosin local wisdom at Banbart Community. The process of blowpipe welding was necessary to produce the bowl which was very dangerous or 93.59% risk. After the employment of new sitting posture, the work risk was lower 48.41% or moderate risk. When considering in details, it was found that: 1) the traditional sitting posture could create work risk at 88.89% while the new sitting posture could create the work risk at 58.86%. 2) About the environmental pollution, with the traditional sitting posture, workers exposed to the polluted fume from welding at 61.11% while with the new sitting posture workers exposed to the polluted fume from welding at 40.47%. 3) On accidental risk, with the traditional sitting posture, workers exposed to the accident from welding at 94.44% while with the new sitting posture workers exposed to the accident from welding at 62.54%.

Keywords: occupational health safety, environment at work, Monk’s food bowl, machine intelligence

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Authors: Suzanne Giasson, Alberto Guerron

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Stimuli-responsive polymer coatings can be used as functional elements in nanotechnologies, such as valves in microfluidic devices, as membranes in biomedical engineering, as substrates for the culture of biological tissues or in developing nanomaterials for targeted therapies in different diseases. However, such coatings usually suffer from major shortcomings, such as a lack of selectivity and poor environmental stability. The study will present multi-responsive hierarchical and hybrid polymer-based coatings aiming to overcome some of these limitations. Hierarchical polymer coatings, consisting of two-dimensional arrays of thermo-responsive cationic PNIPAM-based microgels and surface-functionalized with non-responsive or pH-responsive polymers, were covalently grafted to substrates to tune the surface chemistry and the elasticity of the surface independently using different stimuli. The characteristic dimensions (i.e., layer thickness) and surface properties (i.e., adhesion, friction) of the microgel coatings were assessed using the Surface Forces Apparatus. The ability to independently control the swelling and surface properties using temperature and pH as triggers were investigated for microgels in aqueous suspension and microgels immobilized on substrates. Polymer chain grafting did not impede the ability of cationic PNIPAM microgels to undergo a volume phase transition above the VPTT, either in suspension or immobilized on a substrate. Due to the presence of amino groups throughout the entirety of the microgel polymer network, the swelling behavior was also pH dependent. However, the thermo-responsive swelling was more significant than the pH-triggered one. The microgels functionalized with PEG exhibited the most promising behavior. Indeed, the thermo-triggered swelling of microgel-co-PEG did not give rise to changes in the microgel surface properties (i.e., surface potential and adhesion) within a wide range of pH values. It was possible for the immobilized microgel-co-PEG to undergo a volume transition (swelling/shrinking) with no change in adhesion, suggesting that the surface of the thermal-responsive microgels remains rather hydrophilic above the VPTT. This work confirms the possibility of tuning the swelling behavior of microgels without changing the adhesive properties. Responsive surfaces whose swelling properties can be reversibly and externally altered over space and time regardless of the surface chemistry are very innovative and will enable revolutionary advances in technologies, particularly in biomedical surface engineering and microfluidics, where advanced assembly of functional components is increasingly required.

Keywords: responsive materials, polymers, surfaces, cell culture

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Authors: Siyamak Sarafraz, Reza Esmaeil Pour, Saeed Jamshidi, Asghar Molaei Dehkordi

Abstract:

Cutting transport is one of the major problems in directional and extended reach oil and gas wells. Lack of sufficient attention to this issue may bring some troubles such as casing running, stuck pipe, excessive torque and drag, hole pack off, bit wear, decreased the rate of penetration (ROP), increased equivalent circulation density (ECD) and logging. Since it is practically impossible to directly observe the behavior of deep wells, a test setup was designed to investigate cutting transport phenomena. This experimental work carried out to scrutiny behavior of the effective variables in cutting transport. The test setup contained a test section with 17 feet long that made of a 3.28 feet long transparent glass pipe with 3 inch diameter, a storage tank with 100 liters capacity, drill pipe rotation which made of stainless steel with 1.25 inches diameter, pump to circulate drilling fluid, valve to adjust flow rate, bit and a camera to record all events which then converted to RGB images via the Image Processing Toolbox. After preparation of test process, each test performed separately, and weights of the output particles were measured and compared with each other. Observation charts were plotted to assess the behavior of viscosity, flow rate and RPM in inclinations of 0°, 30°, 60° and 90°. RPM was explored with other variables such as flow rate and viscosity in different angles. Also, effect of different flow rate was investigated in directional conditions. To access the precise results, captured image were analyzed to find out bed thickening and particles behave in the annulus. The results of this experimental study demonstrate that drill string rotation helps particles to be suspension and reduce the particle deposition cutting movement increased significantly. By raising fluid velocity, laminar flow converted to turbulence flow in the annulus. Increases in flow rate in horizontal section by considering a lower range of viscosity is more effective and improved cuttings transport performance.

Keywords: cutting transport, directional drilling, flow rate, hole cleaning, pipe rotation

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Authors: Saumya R. Jha, Krishanu Biswas, Nilesh P. Gurao

Abstract:

Several recent investigations have revealed medium entropy alloys exhibiting better mechanical properties than their high entropy counterparts. This clearly establishes that although a higher entropy plays a vital role in stabilization of particular phase over complex intermetallic phases, configurational entropy is not the primary factor responsible for the high inherent strengthening in these systems. Above and beyond a high contribution from friction stresses and solid solution strengthening, strain hardening is an important contributor to the strengthening in these systems. In this regard, researchers have developed severe plastic deformation (SPD) techniques like High Pressure Torsion (HPT) to incorporate very high shear strain in the material, thereby leading to ultrafine grained (UFG) microstructures, which cause manifold increase in the strength. The presented work demonstrates a meticulous study of the variation in mechanical properties at different radial displacements from the center of HPT tested equiatomic ternary FeMnNi synthesized by casting route, which is a low stacking fault energy FCC alloy that shows significantly higher toughness than its high entropy counterparts like Cantor alloy. The gradient in grain sizes along the radial direction of these specimens has been modeled using microstructure entropy for predicting the mechanical properties, which has also been validated by indentation tests. The dislocation density is computed by FEM simulations for varying strains and validated by analyzing synchrotron diffraction data. Thus, the proposed model can be utilized to predict the strengthening behavior of similar systems deformed by HPT subjected to varying loading conditions.

Keywords: high pressure torsion, severe plastic deformation, configurational entropy, dislocation density, FEM simulation

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Authors: Naren Bag, S. Bhattacharyya, Partha P. Gopmandal

Abstract:

In this study, we have analyzed the transport of analytes under a two dimensional steady incompressible flow of power-law fluids through rectangular nanochannel. A mathematical model based on the Cauchy momentum-Nernst-Planck-Poisson equations is considered to study the combined effect of mixed electroosmotic (EO) and pressure driven (PD) flow. The coupled governing equations are solved numerically by finite volume method. We have studied extensively the effect of key parameters, e.g., flow behavior index, concentration of the electrolyte, surface potential, imposed pressure gradient and imposed electric field strength on the net average flow across the channel. In addition to study the effect of mixed EOF and PD on the analyte distribution across the channel, we consider a nonlinear model based on general convective-diffusion-electromigration equation. We have also presented the retention factor for various values of electrolyte concentration and flow behavior index.

Keywords: electric double layer, finite volume method, flow behavior index, mixed electroosmotic/pressure driven flow, non-Newtonian power-law fluids, numerical simulation

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Authors: Adji Achmad Rinaldo Fernandes, Usriatur Rohma

Abstract:

Nonparametric path analysis is a statistical method that does not rely on the assumption that the curve is known. The purpose of this study is to determine the best truncated spline nonparametric path function between linear and quadratic polynomial degrees with 1, 2, and 3 knot points and to determine the significance of estimating the best truncated spline nonparametric path function in the model of the effect of perceived benefits and perceived convenience on behavior to convert waste into economic value through the intention variable of changing people's mindset about waste using the t test statistic at the jackknife resampling stage. The data used in this study are primary data obtained from research grants. The results showed that the best model of nonparametric truncated spline path analysis is quadratic polynomial degree with 3 knot points. In addition, the significance of the best truncated spline nonparametric path function estimation using jackknife resampling shows that all exogenous variables have a significant influence on the endogenous variables.

Keywords: nonparametric path analysis, truncated spline, linear, kuadratic, behavior to turn waste into economic value, jackknife resampling

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