bluuebunny/crossref_metadata_2025 huggingface dataset:
Qualitative Methods in Organizational Research
Authors: Kamasak Rifat , Kar Altan , Yavuz Meltem , Baykut Sibel
Published: March 2017

This chapter aims to elaborate different research methods that can be employed in organizational studies. Since the complex and indivisible relationships between the constructs and nature of the social content about the phenomena can be understood better through qualitative methods, importance of qualitative investigation is mentioned and a detailed explanation of grounded theory data analysis as a qualitative method is provided. Grounded Theory mainly suggests that theory can be discovered in qualitative data. The theory employs a specific method that follows symbolic interactionism in viewing humans as active agents in their own lives who create meaning in the processes of action and interaction. Grounded Theory which deems researchers as active participants in the construction of knowledge leading to generation of theory has been used in organizational research widely. Therefore, the chapter also offers an example of the application of grounded theory by using several extracts from the sample transcripts of interviewees.
Human Resource Management and Organizational Reliability
Authors: Ferrari Filippo
Published: March 2017

In the International Strategic Management (ISM) field of research, a frequently studied problem is the impact of distance (both geographical and cultural) on organizational effectiveness and reliability. Furthermore, in multinational corporates, Human Resource Management practices play a fundamental role in order to provide peculiar skills to operators. In fact, in high reliability organizations (HROs), the operator is one who addresses operational issues, often far (hierarchically and physically) from the managerial level, alone or as part of a team. This article discusses issues related to 1) the coordination mechanisms used by a multinational organization to ensure reliability, 2) the characteristics possessed by the operator, and 3) the training strategies that should be used to develop their skills; provides a discussion of 4) the relationship between the group agent (team) and organizational reliability; lastly this chapter proposes 5) a diagnostic model in order to check the organizational reliability.
Traits of Leaders and Active Listening
Authors: Kumar Rajiv , Jha Vidyanand
Published: March 2017

Listening is an important managerial competency which contributes to managerial effectiveness and also contributes to many positive outcomes at organizational and individual level. In this paper, we investigate, the relationship between personality types and listening styles with a view to find specific listening styles appropriate to different personality types. We have argued that active listening is impacted by the traits leaders have. Employing the well-established taxonomy of the Big-Five traits, we have formulated five propositions predicting the likely impact of each of these traits on active listening. Extraversion and neuroticism are likely to take a leader away from active listening, but the other three traits—agreeableness, conscientiousness, and openness to new experiences—seem to enable active listening. We have also discussed the implications of our work for theory and practice.
Social Media Support for the Occupation of Public Schools in São Paulo, Brazil
Authors: Corrêa Cynthia H. W.
Published: March 2017

Networked social movements have amplified the emancipation of protesters everywhere. In Brazil, a conflict arose after the São Paulo State Secretariat for Education announced the closing of 94 public schools, impacting 311,000 people. In response, about 30 students organized the occupation of the State School Fernão Dias Paes. Subsequently, the occupation spread to other schools. Based on a case study of the first school occupied in the city of São Paulo, this research aims to identify the role of information and communication technologies (ICTs) and social media tools in generating and sustaining the successful occupation protest of public schools in São Paulo. This chapter covers theories on demonstrations initiated online, on the social panorama in Latin America and educational issues in Brazil. It also addresses and analyzes the occupation process at this school, which reached visibility and support at national and international levels using ICTs and social media, confirming the steps of occupy movements around the world.
Information and Communication Technologies as Drivers of Social Unrest
Authors: Garcia-Murillo Martha , Zaber Moinul , Wohlers de Almeida Marcio
Published: March 2017

Information and communication technologies (ICTs) are alleviating frictions associated with the gathering and distribution of information, as well as reducing transaction costs related to the identifying, monitoring, and coordination of citizens dissatisfied with certain government policies. We conducted a random-effect logit tests based on a uniquely developed panel dataset of 138 countries from 2005 to 2014 to determine, ceteris paribus, whether or not ICTs play a role in facilitating changes to the status quo that gravitate against government policies. We found that ICTs although it can reduce hysteresis, the tendency to remain passive, inertia, is stronger. In addition, because ICTs are multi-purpose technologies they also support other beneficial economic and political activities which can explain why we don't see greater evidence of social unrest with these technologies. The literature on social unrest provide some clues about this phenomenon. People are willing to engage in these movements but it appears that only during a crisis.
The Formation of Consensus in Iranian Online Communities
Authors: Honari Ali
Published: March 2017

For several years now, the role that digitally mediated social movements and online communities play in challenging authoritarian regimes in the Middle East and North Africa has been extensively debated. The focus of attention on the political use of the Internet shapes conventional wisdom that political issues are widespread in online communities in these contexts and that the users are predominantly oppositional users with political democratic motivations. Using fresh methods and techniques to gather a variety of online data, this chapter argues and reveals that, at least in the case of Iran, this view selectively overlooks the diversity of users and the broad range of issues frequently and intensively discussed among users in online communities. The failure to examine a broader range of issues means that scholars have neglected how consensus forms and develops among online users in other issues. This study broadens our understanding of the current social issues and possible areas of change in Iran through investigating a more comprehensive frame of the Iranian web.
Emotional Aspects of Leadership in the Modern Workplace
Authors: Giannouli Vaitsa
Published: March 2017

Although leadership has been extensively examined in the field of industrial-organizational psychology, management and business, until now there is scarce research focusing on the different emotional aspects of the leaders and the influence that they may have on their subordinates. This review explores emotions in healthcare workplaces-hospitals through the prism of emotional intelligence, emotion regulation, emotional labor, job satisfaction, burnout, and anxiety. The above emotional aspects of employees are presented along with selected paradigms coming from the Greek and international modern healthcare management research. The chapter closes with future directions-research questions on leadership issues in the modern healthcare workplace.
Welfare Regime
Authors: Patro Chandra Sekhar
Published: March 2017

In the present competitive business environment, it is essential for the management of any organization to precisely manage the welfare services to be provided for their employees. An organization is certainly a place where employees' and employers try to get the maximum from each other. Both, there can be lot more if and when they work together as partners in an organization, and if they have compassion of understanding of each other problems, which is the basic problem in employee welfare. The extreme logic in the wake of providing welfare services is to create proficient, healthy, loyal and satisfied labour force for an organization. The aim of the chapter is to articulate the welfare services administered by the organizations to the employees and their effect on the employees' efficacy and work life. It also examines the various principles and theories of welfare along with measures to improve welfare facilities in the organizations.
Performance Appraisal System Effectiveness
Authors: Patro Chandra Sekhar
Published: March 2017

Performance appraisal system (PAS) has been noticed to be one of the most challenging activities of human resource management and is even a destructive effect on the relationship of employees and employers. It not only motivates the employee but also improves the productivity level of an organization. Performance appraisal is considered to be a key instrument and is practiced in almost all types of organizations, but with a few differences. In an effort to change the behaviors and attitudes of employees in the organizations, performance appraisal systems have incorporated the new values and desired behaviors. In this contemporary state the organizations have become more enthusiastic to augment the performance of their employees. The chapter aims at identifying the performance appraisal system undertaken in the organizations and its influence on employees' competency and efficiency. It emphasizes on the problems and consequences faced by the organizations, and also the best practices undertaken for successful execution.
Emotional Intelligence and Job Stress
Authors: Washington Germaine D. , Shen Libi
Published: March 2017

Substance abuse professionals work with chemically dependent addicts and disgruntled coworkers. They experience more occupational stress and employee turnover than social workers, community support workers, and youth care workers. Three of 37 substance abuse agencies in Kansas City, Missouri have reported extremely high employee turnover rates and occupational stress. How do substance abuse professionals perceive the relationship between emotional intelligence and job stress? What are substance abuse professionals' definitions of emotional intelligence and job stress? How does emotional intelligence affect job stress in the substance abuse profession? Why do higher levels of emotional intelligence reduce people's job stress and improve their job performance? The purposes of this chapter are to explore substance abuse professionals' definitions of emotional intelligence and job stress, and their viewpoints on the relationship between emotional intelligence and job stress.
The Diversity Management for Employment of the Persons With Disabilities
Authors: Seino Kai , Nomoto Aoi , Takezawa Tomohiro , Boeltzig-Brown Heike
Published: March 2017

The purpose of this chapter is to discuss the latest knowledge of effective diversity management—from businesses and academia—with regard to the employment of persons with disabilities. From a broad perspective, this knowledge is found in the field of industrial-organizational psychology. From a more narrow perspective, and based on evidence from a substantial study, the knowledge of vocational rehabilitation has relevance for persons with disabilities. Vocational rehabilitation is the practice of providing employment supports that will build win-win relationships between employers and persons with disabilities. This chapter reviews recent findings documenting the effective employment and management of persons with disabilities, and summarizes effective actions and workplace considerations for the employment of persons with disabilities.
Employer Branding and Internet Security
Authors: Matuska Ewa Maria , Grubicka Joanna
Published: March 2017

This chapter promotes the concept of employer branding (EB) as special kind of value management being part of strategic human resources management (SHRM) and including elements of cyber security. Employees' and organization's shared values (EVPs) bring opportunity to create common sense of identity, which prevents potentially aversive behavior towards company's reputation. Chapter's background positions EB and EVP in process of SHRM, introduces the view of EB as architectural frame for core organizational values, and describes popular Internet tools of EB. The background is closed by descriptions of common Internet threats, their implications to overall organization's information security, as well as useful Internet security systems. Chapter concludes with recommendations regarding enhancing EB by better controlling company's information security. As a new research area is proposed sub-discipline of cyber security in management, with special dedication to SHRM.
National Ethical Institutions and Social Entrepreneurship
Authors: Muralidharan Etayankara , Pathak Saurav
Published: March 2017

Using insights from institutional theory, the chapter proposes understanding ethics as national institutions that deeply influence social entrepreneurship. Moreover, the chapter proposes that low behavioral ethical standards (normative ethical institutions) provide opportunities for individuals to establish social enterprises. Furthermore, it proposes that high public-sector ethical standards (regulatory ethical institutions) and values of unselfishness (cognitive ethical institutions) facilitate and motivate individuals to establish social enterprises. The chapter also explores the combined effects of public-sector ethical standards and low behavioral ethics, public-sector ethical standards and societal unselfishness, and low behavioral ethics and unselfishness, on the creation of social enterprises. The chapter contributes to cross-cultural comparative entrepreneurship by suggesting, through a multilevel framework, the effects of societal-level ethical institutions on the creation of social enterprises.
Factors Related to Readjustment to Daily Life
Authors: Naito Yoko
Published: March 2017

This study explores issues arising from cross-cultural transitions, focusing on Japanese multinational enterprises (MNEs) and readjustment to daily life in general after international assignments. Employee readjustment to the home country needs to study from two perspectives: work and private life. However, most studies of repatriates focus on the work aspect, and few focus on the aspect of private life. Using structural equation modeling based on the questionnaire data, this study empirically examines nine variables that may possibly affect readjustment to daily life in general after returning to Japan. In this process, this study deals with “readjustment to daily life in general” from a viewpoint outside the organization. Based on these findings, this chapter suggests emphasizing management practices that provide assistance and support to repatriates in their readjustment to daily life in general, along with the importance of readjustment to the organization.
Investigation of Ergonomic Risk Factors in Snacks Manufacturing in Central India
Authors: Mukhopadhyay Prabir
Published: March 2017

Hand-made snacks (locally known as papadam) manufacturing is a popular profession in Central India employing a large number of women workers The objective of this study was to identify the ergonomic risk factors for Work related musculoskeletal disorders (WMSDs) in this sector. Direct observation, activity analysis was applied along with postural analysis methods. Pre and post exercise heart rate was measured by the 10 beats method. Lower back (30%), upper arm (30%) and shoulder were the zones where maximum post work pain and discomfort was reported in the dough cutting section. The maximum post work heart rate was at 116.3 beats per minute in the dough cutting section. High REBA score of 15/15 was observed in the grading, kneading and dough cutting sections. Similarly the RULA scores were very high at 7/7 in majority of the sections. Strain Index scores were very high at 60.8 in the dough cutting section.
Expanding Notions of Access
Authors: Ehlinger Emily
Published: March 2017

This chapter focuses on disability access in higher education and the role that Universal Design has played in improving meaningful participation and inclusion of students with disabilities. The purpose of this chapter is to provide an overview of several frameworks of Universal Design that are specific to the context of instruction and learning, as well as the scholarship and theory related to implementation of these frameworks in postsecondary classroom environments. Scholarship on how current Universal Design frameworks might be expanded to address a broader set of access and equity issues, as well as the limitation of the current research about its application and effectiveness are also discussed. The chapter closes with a synthesis of opportunities and future directions for research, scholarship, and practice related to the development and implementation of Universal Design frameworks in higher education.
Institutional, Legal, and Attitudinal Barriers to the Accessibility of University Digital Libraries
Authors: Oswal Sushil K.
Published: March 2017

This chapter takes a look at the impact of accessibility barriers to today's digital libraries on disabled students' ability to succeed and considers the wider institutional implications of such barriers in light of disability laws in the United States. It analyzes the implications of these barriers from the broader institutional policy perspective in improving the access to higher education for users with print disabilities. The author concludes by reiterating that achieving technical accessibility through adherence to industry or legal standards alone is not adequate for making usable research and teaching libraries available to students and scholars with print disabilities. The author also emphasizes that engaging actual disabled users both in the design and development stages of the platforms, user interfaces, and content presentation schemas for these knowledge repositories is of utmost importance.
An Investigation Into the Gamification of E-Learning in Higher Education
Authors: Annansingh Fenio
Published: March 2017

The concept of gamification has gained significant attention from practitioners and academics alike. Using game mechanics and dynamics to support an e-learning platform can increase learners' motivation, engagement, and retention areas, which have been proven to be challenging in the past. This chapter proposes a conceptual gamified e-learning framework which addresses some of the issues facing such environments. Further work needs to be done to standardize the framework by testing and applying it to a gamified e-learning environment.
Performance Evaluation of VM Placement Using Classical Bin Packing and Genetic Algorithm for Cloud Environment
Authors: Sharma Oshin , Saini Hemraj
Published: March 2017

In current era, the trend of cloud computing is increasing with every passing day due to one of its dominant service i.e. Infrastructure as a service (IAAS), which virtualizes the hardware by creating multiple instances of VMs on single physical machine. Virtualizing the hardware leads to the improvement of resource utilization but it also makes the system over utilized with inefficient performance. Therefore, these VMs need to be migrated to another physical machine using VM consolidation process in order to reduce the amount of host machines and to improve the performance of system. Thus, the idea of placing the virtual machines on some other hosts leads to the proposal of many new algorithms of VM placement. However, the reduced set of physical machines needs the lesser amount of power consumption therefore; in current work the authors have presented a decision making VM placement system based on genetic algorithm and compared it with three predefined VM placement techniques based on classical bin packing. This analysis contributes to better understand the effects of the placement strategies over the overall performance of cloud environment and how the use of genetic algorithm delivers the better results for VM placement than classical bin packing algorithms.
A Secure and Robust Three-Factor Based Authentication Scheme Using RSA Cryptosystem
Authors: Ali Rifaqat , Pal Arup Kumar
Published: March 2017

In remote user authentication, a server confirms the authenticity of a user via unreliable channel. Several authentication protocols are devised in the literature relied on the identity, password and biometric of a user. But, most of the authentication protocols are either computationally expensive or not-secure from several kinds of malicious threats. In this document, the authors have suggested a secure and robust three-factor (such as password, smartcard and biometric) based authentication scheme by using RSA cryptosystem. The proposed protocol is validated through BAN logic. Then, formal security analysis using random oracle model shows that the identity, password, biometric and session key are highly secure from an adversary. Besides, the informal security analysis of our protocol proves that it withstands to several kinds of malicious attacks. In addition, performance comparison of presented scheme with respect to other schemes is comparatively suitable in the context of communication and computation costs.
Cryptanalysis and Security Enhancement of Three-Factor Remote User Authentication Scheme for Multi-Server Environment
Authors: Chandrakar Preeti , Om Hari
Published: March 2017

Recently, Om et al. proposed three-factor remote user authentication protocol using ElGamal cryptosystem and ensured that it is withstands to various kinds of security attacks. But, the authors review carefully Om et al.'s scheme and discover that it unable to resist three attacks (like password guessing; denial of service; and user impersonation). Moreover, their protocol is not facilitating user anonymity. To solve these security vulnerabilities, the authors devise a secure and robust anonymous identity based authentication scheme for multi-server environment. The authentication proof of the proposed scheme has validated using BAN (Burrows-Abadi-Needham) logic, which confirms the protocol facilitates mutual authentication and session-key negotiation securely. Informal security analysis also confirms that it is well protected against various security attacks. In addition, the proposed work is compared along with other schemes (in the context of smart card storage and computation costs as well as execution time).
Enabling Rapid Classification of Social Media Communications During Crises
Authors: Imran Muhammad , Mitra Prasenjit , Srivastava Jaideep
Published: March 2017

The use of social media platforms such as Twitter by affected people during crises is considered a vital source of information for crisis response. However, rapid crisis response requires real-time analysis of online information. When a disaster happens, among other data processing techniques, supervised machine learning can help classify online information in real-time. However, scarcity of labeled data causes poor performance in machine training. Often labeled data from past event is available. Can past labeled data be reused to train classifiers? We study the usefulness of labeled data of past events. We observe the performance of our classifiers trained using different combinations of training sets obtained from past disasters. Moreover, we propose two approaches (target labeling and active learning) to boost classification performance of a learning scheme. We perform extensive experimentation on real crisis datasets and show the utility of past-labeled data to train machine learning classifiers to process sudden-onset crisis-related data in real-time.
Mapping of Areas Presenting Specific Risks to Firefighters Due to Buried Technical Networks
Authors: Grangeat Amélie , Raclot Stéphane , Brill Floriane , Lapebie Emmanuel
Published: March 2017

Vehicles or freight cars on fire below a bridge or inside a tunnel are exceptional events and imply difficult intervention conditions for firefighters. A buried technical network like high voltage electricity line, gas or steam pipeline around such a fire causes additional specifics risks. Vulnerability areas for firefighters are zones where both factors exist: a difficult incident area together with a specific risk like buried networks. They require intervention teams with specific emergency response capabilities. The paper proposes a method developed for the Paris Fire Brigade for vulnerability mapping. Results aim at improving the mobilization in allocating directly the specific responses capabilities intervention teams. Results are debated from an operational point of view. Cutting off several network lines during firefighters' interventions may strongly affect the society. In case of simultaneous incidents in vulnerable areas, firefighters could be an early warning system and inform authorities of the risk of services disruption.
Synergistic Effect on Formation of Radiation Damage in CLAM Steel Studied by Triple Beam Irradiation
Authors: Yuan Da Qing , Ma Hai Liang , Fan Ping , Zheng Yong Nan , Zuo Yi , Zhang Qiao Li , Wen Ali , Feng Wei , Liang Jun Chen , Xiong Wen Jun , Ma Xiao Qiang , Cui Bao Qun , Chen Li Hua , Jiang Wei Sheng , Huang Qun Ying , Wu Yi Can , Lei Peng , Cao Xing Zhong , Wang Bao Yi , Wei Long , Xia Hai Hong , Zhu Sheng Yun
Published: March 2017

The synergistic effect associated with displacement damage, hydrogen and heliumin the China Low Activation Martensitic (CLAM) steel has been investigated using the triple ion beamirradiation. Triple ion beams, an iron beam of 109 MeV degraded by a tantalum foil of 7.45 μm thick, the100 keV hydrogen and 200 keV helium, were injected into the CLAM steel samples simultaneously or sequentially.The radiation damage examinations were carried out by the slow positron Doppler broadening technique. Themeasured S parameters indicate that the radiation damage is different for different irradiationprocedures with same dpa and concentrations of H and He. The sample suffers most severe damage in the simultaneoustriple beam irradiation. The present experimental results support the molecular dynamics simulation result that the H facilitates the He-bubble nucleation and growth.
Positron Spectroscopy of Defects in Hydrogen-Saturated Zirconium
Authors: Bordulev Yurii , Lee K. , Laptev Roman S. , Kudiiarov Viktor N. , Lider Andrey M.
Published: March 2017

Zirconium alloys, such as Zr-1Nb are widely used as cladding materials for nuclear fuel elements of light water reactors. Hydrogen embrittlement problem causes degradation of these parts of nuclear reactors. It is known, that hydrogen uptake causes changes in microstructure and defect structure of metals. The aim of this work is study of Zr-1Nb alloys’ defect structure after hydrogen saturation up to the concentration of 600 ppm. Saturation of hydrogen was carried out from the gas phase under high temperature and pressure. This study reveals the increase of average positron lifetime with the increase of hydrogen concentration. Value of the average positron lifetime achieves plateau when the concentration of hydrogen is about 600 ppm. Also the following effects were detected in the material after hydrogen uptake up to different concentrations: crystal lattice expansion, dislocations and vacancy-like defects formation, as well as the defect-hydrogen complexes formation.
Positron Annihilation and TEM Characterization of Cu-Enriched Clusters in the Ferritic Steels Containing Copper
Authors: Chen Zhi Lin , Liu Xiang Bing , Wu Yi Chu , Wang Rong Shan , Xue Fei , Huang Ping , Xu Chao Liang , Qian Wang Jie
Published: March 2017

Nanosized Cu-enriched clusters formed in Cu-containing reactor pressure vessel (RPV) steels during service have a deleterious effect on mechanical properties, which can result in RPV embrittlement and limit reactor operation life. To understand the effect of Cu-enriched clusters (CECs) behavior on mechanical properties, thermal aging at 370°C for times up to 13200 h was performed on the high-copper ferritic steels. The microstructure evolution of CECs was investigated by positron annihilation spectroscopy (PAS) and transmission electron microscope (TEM). The results show that the CECs formed after aging times up to 3000 h, which composition is composed of Fe, Cu, Ni, Mn, and Si, are 9R structures. The CECs lead to precipitation hardening/embrittlement effects. The changes of hardness have a linear relationship with transition temperature shifts.
Effect of FLiBe Infiltration Pressure on Microstructure of Matrix for TMSR Fuel Elements (FEs)
Authors: Xu Hong Xia , Lin Jun , Chen Yu , Gu Bing Chuan , Ye Bang Jiao , Zhu Zhi Yong , Jiang Hai Tao , Zhong Ya Juan , Liu Bing
Published: March 2017

The matrix graphite of fuel elements (FEs) with infiltration of 2LiF-BeF2(FLiBe) at different pressures varying from 0.4 MPa to 1.0 MPa, has been studied by X-ray diffraction (XRD), scanning electron microscope (SEM) and positron annihilation lifetime (PAL) measurement. The result of XRD reveals that diffraction patterns of FLiBe appear in matrix graphite infiltrated with FLiBe at a pressure of 0.8 MPa and 1.0 MPa. The surface morphology from SEM shows that FLiBe mainly distributes within macro-pores of matrix graphite. PAL measurement indicates that there are mainly two positron lifetime components in all specimens:τ1~0.21 ns and τ2 ­~0.47 ns, ascribed to annihilation of positrons in bulk and trapped-positrons at surface, respectively. The average positron lifetime decreases with infiltration pressure, due to the decrease in annihilation fraction of positrons with surface after infiltration of FLiBe into macro-pores.
Effect of TiO2 Doping on Microdefects and Electrical Properties of ZnO-Based Varistors
Authors: Chen Zheng Ying , Li Mei Yu , Wan Yan , Han Li Fang , Huang Yu Yang , Deng Wen
Published: March 2017

Positron lifetime spectrum and electrical property measurements were performed on ZnO-based ceramics doped with different contents of TiO2. For ZnO-based ceramics with TiO2 content less than 1.8 mol%, the mean positron lifetime of the ZnO-based ceramic decreases with increasing in TiO2 content, and reaches a minimum value at 1.8 mol% TiO2. As the TiO2 content higher than 1.8 mol%, the mean positron lifetime increases with TiO2 content. The ZnO-based varistor with 1.8 mol% TiO2 exhibites an optimized varistor property; it has a relatively low leakage current IL, a relatively low breakdown voltage VB, and a relatively high nonlinear coefficient α. The effects of TiO2 doping on microdefects and electrical properties of ZnO-based varistors were discussed.
Effect of Annealing Process on the Photoelectric Properties and Microstructure of Sulfur-Hyperdoped Silicon
Authors: Liu De Wei , Li Tao , Dai Hai Yang , Xue Ren Zhong , Chen Zhen Ping , Cao Xing Zhong , Wang Bao Yi
Published: March 2017

The material of sulfur-hyperdoped silicon was prepared by ion implantation and then annealed by heat treating furnace and pulse laser respectively. The effects of annealing process on the absorption, raman shift, carrier concentration and mobility ratio of this material were researched. Furthermore, the doppler broadening spectrum of crystal silicon substrate and sulfur-hyperdoped silicon before and after annealing was presented by using a slow positron technique. And the relationship between the microstructure and photoelectric properties of the material was explored. The experimental results indicate that the absorption and carrier concentration of the sulfur-hyperdoped silicon annealed by pulse laser were higher than that of the samples annealed by heat treating furnace. And the doppler broadening spectrum shows that the photoelectric properties of this material were closely related to the defects in the material.
Influence of the Crosslinking Content on the Structural Properties of Polybutadiene Rubbers with Different Isomeric Composition
Authors: Rodriguez Garraza Ana , Mansilla Marcela , Macchi Carlos , Cerveny Silvina , Marzocca Angel , Somoza Alberto
Published: March 2017

In the present work first results on structural properties of three commercial isomers of polybutadiene rubber are presented. To this aim, rheometry, PALS, DSC and swelling techniques were used. Different samples were prepared containing diverse amounts of dycumil peroxide as crosslinking agent and vulcanized at 433 K.A correlation among the experimental results obtained using different techniques is also discussed.
Investigation of Micro-Sized Capsules at High Pressure by PALS Method
Authors: Zgardzińska Bożena , Tydda Maciej , Wawryszczuk Jan
Published: March 2017

The positron annihilation lifetime spectroscopy (PALS) was applied to investigate the properties of capsules composed of n-alkanes (filling material) and polymer (shell) in the broad range of pressures up to 450 MPa. These microcapsules aggregate into the grains having about 200 μm in diameter. Their properties were investigated as a function of pressure (p) at several selected temperatures: when the filling material is in liquid, rotator and solid phase. Pressure experiments were performed without gas access to the sample and in an argon atmosphere. Two o-Ps components were found, the longer-lived correspond to the filler material, and the shorter-lived one – to the shell. These components change with p; even a small pressure (6 MPa) reduces considerably the o-Ps lifetimes (τ). At 303 K the o-Ps lifetime in the core changes non-monotonically, and at 60 MPa τ is higher than at 20 MPa. The increase of pressure induces the phase changes in the filling material, and also produces the deformation of microcapsule aggregates and crash of small capsules at the grain boundary region. Internal structure of the microcapsules was observed by SEM.
Characterisation of Porosity in Zirconia-Based Nanopowders
Authors: Procházka Ivan , Čížek Jakub , Melikhova Oksana , Hruška Petr , Anwand Wolfgang , Konstantinova Tetyana E. , Danilenko Igor A.
Published: March 2017

Porosity in several zirconia-based pressure compacted nanopowders was studied using the positron lifetime technique combined with the mass-density measurements. Two kinds of pores were identified: (i) the larger pores of ≈ 10 to 19 nm diameter arising likely from a formation of secondary particle aggregates, and (ii) the smaller ones (≈ 1 nm) which are obviously of a more complex origin.
Ion Desorption from TiO2(110) by Low Energy Positron Impact
Authors: Tachibana Takayuki , Chiari Luca , Nagira Masaru , Hirayama Takato , Nagashima Yasuyuki
Published: March 2017

We have observed positron-stimulated ion desorption from a TiO2(110) surface. H+ and O+ ions were desorbed at incident positron energies above the desorption thresholds for electron impact. However, only O+ ions were detected at energies below those thresholds. These results suggest that by surface ionization positron annihilation as well as by positron impact leads to the O+ ion desorption. By contrast, it is likely that the H+ ions are not desorbed by positron annihilation, but rather by impact ionization.
New Precision Measurement of Hyperfine Splitting of Positronium
Authors: Ishida Akira
Published: March 2017

Positronium is an ideal system for precision tests of bound-state quantum electrodynamics (QED). One of the most precisely tested quantities of positronium is the ground-state hyperfine splitting (HFS). Recent progress on theoretical calculation revealed that there was a 16.0 ± 3.5 ppm (4.5 σ) discrepancy between the old experimental value and the theoretical calculation. We performed a new measurement which took into account the positronium thermalization effect for the first time. The result was HFS = 203.3942 ± 0.0016 (stat., 8.0 ppm) ± 0.0013 (syst., 6.4 ppm) GHz, which was consistent with the QED calculation within 1.1 σ, whereas it disfavored the old experimental values by 2.6 σ. It also showed that the positronium thermalization effect on HFS was as large as 10 ± 2 ppm, which was consistent with the discrepancy level within 1.5 σ, which could be the reason of the discrepancy. We are planning to preform a new experiment which uses a slow positron beam and perform HFS measurement in vacuum, instead of using gas as all of the other precision measurements. It will be completely free from material effect on HFS, including the thermalization effect. In this proceeding, summary of our previous work and details of the future new experiment are discussed.
Temperature Dependence of Radiation Damage in ODS Steel Studied by Triple Beam Irradiation and Positron Annihilation Techniques
Authors: Yuan Da Qing , Zhang Qiao Li , Fan Ping , Wang Xian Ping , Long Bin , Ma Hai Liang , Zuo Yi , Wen Ali , Zheng Yong Nan , Kong Xiang Shan , Zhuang Zhong , Feng Wei , Liang Jun Chen , Xiong Wen Jun , Lu Er Yang , Cao Xing Zhong , Zhang Peng , Wang Bao Yi , Wei Long , Zhu Sheng Yun
Published: March 2017

The oxide dispersed strengthened (ODS) ferritic-martensitic steel was irradiated by 100MeV iron ion whose energy was degraded by using a Ta foil of 4 μm thick, 100 keV Hydrogen and 200 keV Helium at 480, 515, 550 and 580 °C. The irradiation fluences were 1×1016, 1.1×1015 and 6.8×1013/cm2, respectively for Fe, H and He. The techniques of positron annihilation lifetime and Doppler broadening of slow positron beam were utilized to examine the produced radiation damage. At 550 °C the maximal positron annihilation lifetime and S parameter of Doppler broadening were observed, implyin g tha t 550 °C is the pea k temperature of swelling. The S parameter and annihilation lifetime of the sample irradiated at 515 °C by the single Fe ion beam were smaller compared to the triple beam irradiation at the same temperature, implying that the triple beam irradiation caused more severe damage than the single beam irradiation.
Ultrasonic Wire Cleaning - An Overview
Authors: Hielscher Thomas , Hielscher Kathrin
Published: March 2017

This paper examines the economic costs and benefits of the use of an ultrasonic wire or tape cleaning system. In the last years, major technology improvements made the use of power ultrasound more reasonable for the cleaning of wires. The cavitation of modern high-power ultrasonic processors serves to remove grease, oil, and other contaminations from the surface of the wire. Reduced investment costs and high performance of these ultrasonic wire cleaning systems made them not only competitive but superior to conventional cleaning methods as for example acid baths.
Heat Treatment of Cold Formed Springs Made from Oil Hardened and Tempered Spring Steel Wire
Authors: Geinitz Veronika , Kletzin Ulf
Published: March 2017

The heat treatment after cold forming is used to decrease the residual stresses of springs, but the mechanical characteristics of the spring steel wires alters, too. This presentation describes the influence of the heat treatment technology (oven equipment, temperature, duration,…) to the properties and quality of helical compression springs made from oil hardened and tempered spring steel wire.
Ultrafine-Grained High Strength Cu-Ni-Si Alloys
Authors: Altenberger Igor , Kuhn Hans Achim , Gholami-Kermanshahi Mozhgan , Mhaede Mansour , Wollmann Manfred , Wagner Lothar
Published: March 2017

Ultrafine-grained (UFG) pure copper has been in the focus of materials scientists over the last two decades, however ultrafine-grained high-strength copper alloys have scarcely been processed or characterized so far industrially.In this contribution, UFG copper alloys, especially Cu-Ni-Si alloys, being well known as ideal materials for electromechanical connectors, springs and leadframes, are presented. Precipitation hardened Cu-Ni-Si alloys are a well established and technologically important class of materials for a wide range of applications where high strength and good conductivity are required. Yield strength and fatigue properties of metallic alloys can be significantly enhanced by severe plastic deformation methods. In contrast to other strengthening methods such as solid solution hardening, severe plastic deformation leads to a weaker decrease of electrical conductivity and is therefore a means of enhancing strength while maintaining acceptable conductivity for current bearing parts and components. Characterization of these materials after severe plastic deformation by swaging, wire drawing and subsequent aging was carried out using conductivity-, hardness-and tensile tests as well as highly-resolved microstructural characterization methods.The results reveal that UFG low alloyed copper alloys exhibit impressive combinations of properties such as strength, conductivity, high ductility as well as acceptable thermal stability at low and medium temperatures. By a subsequent aging treatment the severely plastically deformed microstructure of Cu-Ni-Si alloys can be further enhanced and thermal stability can profit from grain-boundary pinning by precipitated nanoscale nickel silicides.
Somatic cell count thresholds in composite and quarter milk samples as indicator of bovine intramammary infection status
Authors: Petzer Inge-Marié , Karzis Joanne , Donkin Edward F. , Webb Edward C. , Etter Eric M.C.
Published: March 2017

The objective of the study was to establish an operational somatic cell count (SCC) threshold to predict the presence of intramammary infection (IMI) in composite milk samples and compare findings with those in quarter milk samples. South African dairy producers now preferred composite milk samples for herd udder health analysis because of increasing cow numbers, convenience of sampling and lower cost. A retrospective study was conducted on 345 461 composite and 89 638 quarter milk samples from South African herds. Variance estimates for the proportion of quarter samples testing positive were adjusted to account for the lack of their independence within individual cows. The IMI at SCC thresholds of 150 000 cells/mL and 200 000 cells/mL differed only by 3.26% in composite milk samples. Youden’s index indicated the optimum SCC thresholds for composite and quarter milk samples as 150 000 cells/mL and 200 000 cells/mL, respectively. At 150 000 cells/mL, sensitivity (95% confidence intervals [CI]) in composite milk samples was 65.3% (64.0%, 66.6%) and specificity was 66.8% (65.7%, 67.9%); and in quarter milk samples, sensitivity at 200 000 cells/ mL was 70.8% (69.5%, 72.0%) and specificity was 63.6% (62.4%, 64.8%). The likelihood of infection for udders and quarters, respectively, was 1.034 and 1.327 at an SCC threshold of 150 000 cells/mL and 0.864 cells/mL and 1.177 cells/mL at 200 000 cells/mL. The area under the curve of the receiver operating characteristics graph was 0.7084 and 0.7277 for composite and quarter samples, respectively, indicating that the SCC test could be considered as a good indicator of IMI in both sample types.
Identifying the determinants of South Africa’s extensive and intensive trade margins: A gravity model approach
Authors: Matthee Marianne , Santana-Gallego Maria
Published: March 2017

Background: The significance of the paper is twofold. Firstly, it adds to the small but growing body of literature focusing on the decomposition of South Africa’s export growth. Secondly, it identifies the determinants of the intensive and extensive margins of South Africa’s exports – a topic that (as far as the authors are concerned) has not been explored before.Aim: This paper aims to investigate a wide range of market access determinants that affect South Africa’s export growth along the intensive and extensive margins.Setting: Export diversification has been identified as one of the critical pillars of South Africa’s much-hoped-for economic revival. Although recent years have seen the country’s export product mix evolving, there is still insufficient diversification into new markets with high value-added products. This is putting a damper on export performance as a whole and, in turn, hindering South Africa’s economic growth.Methods: A Heckman selection gravity model is applied using highly disaggregated data. The first stage of the process revealed the factors affecting the probability of South Africa exporting to a particular destination (extensive margin). The second stage, which modelled trade flows, revealed the variables that affect export volumes (intensive margin).Results: The results showed that South Africa’s export product mix is relatively varied, but the number of export markets is limited. In terms of the extensive margin (or the probability of exporting), economic variables such as the importing country’s GDP and population have a positive impact on firms’ decision to export. Other factors affecting the extensive margin are distance to the market (negative impact), cultural or language fit (positive impact), presence of a South African embassy abroad (positive impact), existing free trade agreement with Southern African Development Community (positive impact) and trade regulations and costs (negative impact). In terms of the intensive margin (or the factors influencing the volume of exports), there are strong parallels with the extensive margin, with the exception being that the time involved in exporting has more of an impact than documentary requirements.Conclusion: Among the factors contributing to South Africa’s exports having largely developed in the intensive margin are a general lack of market-related information, infrastructural weaknesses (both of a physical and technological nature) and a difficult regulatory environment – all of which add to the cost and time involved in exporting. Policymakers have long spoken about the need for the country to diversify its export basket, but now talk about needs to give way to action. The government and its economic partners need to arrive at a common vision of an export sector that will be able to expand into new products and markets, be an active participant in global value chains and deliver sustainable jobs.
Reducing youth unemployment beyond the Youth Wage Subsidy: A study of Simtech apprentices
Authors: Naidoo Mogantheran , Hoque Muhammad E.
Published: March 2017

Orientation: South Africa currently has the twin challenges of worsening youth unemployment and scarce skills that threaten its economic and social stability. Artisanal trades are an occupation category that strongly reflects this current problem. Simtech Training Institute in Durban, the study setting, currently trains artisan apprentices and facilitates their internship work placements.Research purpose: The objective of this study was to identify some of the critical success factors that differentiated Simtech artisan apprentices who obtained permanent employment, compared to those who are currently unemployed.Motivation for the study: The main motivation of the study was to improve the conversion rate of artisan apprentices to permanently employed artisans.Research design, approach and method: The study was a cross-sectional study conducted among 51 artisan apprentices who had graduated over the past 3 years at Simtech and who were selected randomly. An online questionnaire comprising primarily Likert scale type questions was utilised to obtain the responses from the sample. Factor analysis was used to remove scale items from the independent variables that did not impact the variability sufficiently. Then the remaining scale items that impacted variability significantly were combined and categorised as new composite independent variables. Logistic regression analysis identified success factors for permanent employment of Simtech graduates.Main findings: Internship or workplace environment had a statistically significant impact on permanent employment. Youth work ethic had a minor impact on permanent employment status – albeit not a statistically significant one.Practical/managerial implications: These findings showed that improving the internship/ workplace environment can reduce youth unemployment and address skills scarcity.Contribution: Internship host companies and other stakeholders need to urgently focus on improving the quality of the internship/workplace environment experienced by artisan apprentices rather than just on the intake number of artisan apprentices that the Youth Wage Subsidy has encouraged to date.