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This study aims to focus on experimenting the performance of aluminum (Al) powder mixed electric discharge machining (PMEDM) of two different materials viz plastic mould die steel (AISI P20) and nickel-based super alloy (Nimonic 75). This experimental study also focuses on using three different tool materials such as copper, brass and tungsten to analyze their influence on the process output. These materials find many uses in industrial as well as aerospace applications. The performance measures considered in this work are material removal rate (MRR), tool wear rate (TWR) and surface roughness (SR).

The experimental design used in this work is based on Taguchi’s L18 orthogonal array. Besides considering work and tool material as one of the process variables, other process variables are peak current (I_p), pulse on time (T_on) and concentration of powder (C_p). The analysis of variance (ANOVA) is performed on the experimental data to determine the significant variables that influence the output.

It is found that copper produced maximum MRR and brass tool exhibited higher TWR. However, the surface finish of the machined work piece was very much improved by using the brass tool. Though the performance of tungsten tool lies between the above two tool materials, it showed very little wear during EDM with or without the addition of Al powder.

The experimental investigation of PMEDM of nickel-based super alloy (Nimonic 75) has not been attempted before. Besides that, the study on the influence of tungsten tool on the performance of EDM is also very limited.

The purpose of this paper is to investigate the performance of powder-mixed electric discharge machining (PMEDM) using three different powders which are aluminium (Al), silicon carbide (SiC) and aluminium oxide (Al₂O₃). Besides that, the influence of different tool materials was also studied in this experimental investigation. Hence, the work material selected for this purpose was AISI P20 steel and tool materials were copper, brass and tungsten. The performance measures considered in this work were material removal rate (MRR), tool wear rate and radial over cut (ROC).

The process variables considered in this study were powder types, powder concentration, tool materials, peak current and pulse on time. The experimental design, based on Taguchi’s L₂₇ orthogonal array, was adopted to conduct experiments. Significant parameters were identified by performing the analysis of variance on the experimental data.

Based on the analysis of results, it was observed that copper tool combined with Al powder produced maximum MRR (58.35 mm³/min). Similarly, the Al₂O₃ powder combined with tungsten tool has resulted least ROC (0.04865 mm). It was also observed that wear rate of tungsten tool was very low (0.0145 mm³/min).

The experimental investigation of PMEDM involving three different powders (Al, SiC and Al₂O₃) was not attempted before. Moreover, the study of influence of different tool materials (Cu, brass and W) together with the different powders on the electric discharge machining performance was very limited.

The purpose of this paper is to investigate prediction and optimization of multiple performance characteristics in the wire electrical discharge machining (wire-EDM) process of SKD 61 (AISI H13) tool steel.

The experimental studies were conducted under varying wire-EDM process parameters, which were arc on time, on time, open voltage, off time and servo voltage. The optimized responses were recast layer thickness (RLT), surface roughness (SR) and surface crack density (SCD). Arc on time was set at two different levels, whereas the other four parameters were set at three different levels. Based on Taguchi method, an L18 mixed-orthogonal array was selected for the experiments. Further, three methods, namely grey relational analysis (GRA), backpropagation neural network (BPNN) and genetic algorithm (GA), were applied separately. GRA was performed to obtain a rough estimation of optimum drilling parameters. The influences of drilling parameters on multiple performance characteristics were determined by using percentage contributions. BPNN architecture was determined to predict the multiple performance characteristics. GA method was then applied to determine the optimum wire-EDM parameters.

The minimum RLT, SR and SCD could be obtained by setting arc on time, on time, open voltage, off time and servo voltage at 2 ms, 3 ms, 90 volt, 10 ms and 38 volt, respectively. The experimental confirmation results showed that BPNN-based GA optimization method could accurately predict and significantly improve all of the responses.

There were no publications regarding multi-response optimization using a combination of GRA and BPNN-based GA methods during wire-EDM process available.

Proposes the particle model as an improved finite element method for the analysis of metal forming, particularly highlighting the forging process. Analyses the forged material in the present modelling in conjunction with non‐material domain, and expresses the process not by the finite element deformation, but by the “movable particle” which discriminates the material domain. This “fixed mesh” algorithm gives the capabilities treating metal forging problems easily. Demonstrates the effectiveness of the method using some applications.

This paper aims to fabricate a FeS/Cu-Bi copper-based lead-free bearing material to maintain good friction-reducing and anti-adhesive properties under boundary lubrication conditions.

The materials were fabricated by mechanical alloying and powder metallurgy and tested under dry friction conditions using HDM-20 wear tester.

The results show that mechanical alloying can improve the antifriction and wear resistance of the materials. The 6 per cent FeS and 6 per cent Bi in the copper-based bearing materials fabricated by mechanical alloying have a better synergism which contributes to the friction and wear properties of copper matrix.

This new approach solves the problems of Bi and FeS mutual segmentation, mutual agglomeration and poor interface bonding.

This research investigates the market for Western clothing in Vietnam, one of the most under‐developed countries of South East Asia. The intention is to look at factors which will assist economic development in Vietnam because economic growth generally leads to greater GDP per capita and this in turn leads to greater spending per capita on clothing. The country is making use of direct foreign investment (DFI) from the ‘Asian Tigers’ to modernise its industry. The lighter manufacturing industries, which include apparel, are expected to benefit. The population of Vietnam welcome this investment and the employment it is creating, and as the labour force changes from agrarian to urban the GDP is expected to rise. This rudimentary clothing industry is being established in Vietnam mainly to supply the markets in Asia but there are indications that there is a growth of local demand for western clothing. In this research the access to retail western clothing in Vietnam is explored from both secondary and primary data sources, and, conclusions drawn incorporating the economic prospects for the future size of the market. The results of the research show that although the country is experiencing strong growth now and there is demand for western clothing the future market will be small.

The purpose of this research is to investigate how postpartum mothers conduct self-disclosure on social media may obtain social support and therefore improve their depressive mood.

The authors extract variables of self-disclosure by manual coding postpartum mothers' 835 posts from a parenting social media in China. The ordinary least squares model and the binary logistic regression model are used to test the proposed hypotheses.

The study suggests that both mothers' superficial level disclosure and personal level disclosure positively affect online social support received, and the effect of personal level disclosure on social support is much greater than that of superficial level disclosure. Online social support received is related to the content of the post and reduces mothers' depressive mood. The authors further find that the association between personal level disclosure and depressive mood is fully mediated by social support.

The data are collected from a parenting social network. Although it is the major parenting social media with the most users in China, the generalizability of this model and the findings to other social media need additional research.

This study offers implications for researchers and practitioners with regard to social media uses and impacts, which also has important implications for policy and interventions for the mental health of mothers.

This paper makes theoretical contributions to the literature of social penetration theory and social support by (1) dividing self-disclosure into superficial level disclosure and personal level disclosure according to the intimacy of self-disclosure; (2) empirically investigating the direct effect of online self-disclosure on social support and the mediating effect of social support between online self-disclosure and mothers' depressive mood.

This paper aims to investigate the adherence level of current company reports to the International Integrated Reporting Council (IIRC) integrated reporting framework through analysis of whether and to what extent those reports include the content elements of this framework. This study also aims to examine the impact of corporate sustainability characteristics on the adherence level of current company reports to the integrated reporting framework.

The sample for this research comprises the non-financial companies which were listed on Borsa Istanbul, the Turkish stock exchange, as of 31 December 2015. The authors constructed a disclosure index based on the content elements of the IIRC reporting framework. They then measured the integrated reporting disclosure score (IRS) of each company through a manual content analysis of its annual reports and stand-alone sustainability reports. To test the hypotheses, the authors performed a number of statistical analyses.

The authors determined that current company reports mainly present generic risks rather than company-specific; provide positive information while dismissing negative information; present financial and non-financial initiatives separately; lack a strategic focus; and include backward-looking information rather than forward-looking information. Consistent with the predictions, the authors found that the IRS is significantly and positively associated with sustainability reporting, Global Reporting Initiative (GRI) adoption, sustainability index listing and the presence of a sustainability committee.

This study contributes to the literature by enhancing the understanding of integrated reporting practices through the application of a checklist based upon the IIRC integrated reporting framework. Further, this study contributes to the literature by evaluating the impact of corporate sustainability characteristics on IRS.

The five countries in Central Asia, namely Uzbekistan, Kazakhstan, Turkmenistan, Tajikistan, and Kyrgyzstan, are landlocked and therefore rely critically on aviation for passenger travel and express cargo logistics. However, despite substantial growth in the past decade, the aviation market in the region is still not realizing its full potential. This chapter reviews the development status of the international air travel market from Central Asia, with an aim of identifying the key barriers for industrial development and growth, and possible remedies to address these challenges. Overall, our study suggests that international market growth from the region is significantly influenced by historical patterns and political ties with Russia. Whereas markets linking selected countries such as Turkey and the UAE have experienced substantial growth, further liberalization is needed for the region to achieve better connectivity with major trade partners and aviation markets.

This chapter focuses on the Turkish businesses’ and individuals’ perspectives on sustainability and environment and provides a socio-cultural analysis regarding the problems underlying in the implementation of sustainability and environmental practices in an emerging economy.

Current sustainability and environment studies literature regarding the Turkish businesses and society are examined. Socio-cultural perspective is used to explain the problems in the field.

Turkish culture is traditionally associated with harmony with the nature and many studies point to its environmental awareness. But the lack of future orientation, paternalist way of management, and survival concerns of the individuals and businesses cause a certain lack of environmental initiative. Turkish culture has a unique pluralistic approach to nature, and in this approach mastery, harmony, and subjugation are combined.

The suggested pluralistic approach should be considered by the relevant stakeholders to understand the dynamics of business and environment relations in Turkey. This unique structure calls for unique environmental solutions.

Present studies of Turkey in terms of sustainability and environmental issues are generally lacking socio-cultural perspectives. This study aims to fill this gap by suggesting an alternative pluralistic approach based on a socio-cultural evaluation of Turkish culture.