This paper discusses the comparison of micro machining process using conventional and micro wire electrical discharge machining (WEDM) for fabrication of miniaturized components. Seventeen toothed miniaturized spur gear of 3.5 and 1.2 mm outside diameter were fabricated by conventional and micro WEDM respectively. The process parameters for both conventional and micro WEDM were optimized by preliminary experiments and analysis. The gears were investigated for the quality of surface finish and dimensional accuracy which were used as the criteria for the process evaluation. An average surface roughness (R a ) of 50 nm and dimensional accuracy of 0.1-1 µm were achieved in micro WEDM. Whenever applied conventional WEDM for meso/micro fabrication, a R a surface roughness of 1.8 µm and dimensional accuracy of 2-3 µm were achieved. However, this level of surface roughness and dimensional accuracy are acceptable in many applications of micro engineering. A window of conventional WEDM consisting of low energy discharge parameters is identified for micromachining.

The adoption of forecasting approaches such as the multiplicative Holt-Winters (MHW) model is preferred in business, especially for the prediction of future events having seasonal and other causal variations. However, in the MHW model the initial values of the time-series parameters and smoothing constants are incorporated by a recursion process to estimate and update the level (L T), growth rate (b T) and seasonal component (SN T). The current practice of integrating and/or determining the initial value of L T is a stationary process, as it restricts the scope of adjustment with the progression of time and, thereby, the forecasting accuracy is compromised, while the periodic updating of L T is avoided, presumably due to the computational complexity. To overcome this obstacle, a fuzzy logic-based prediction model is developed to evaluate L T dynamically and to embed its value into the conventional MHW approach. The developed model is implemented in the MATLAB Fuzzy Logic Toolbox along with an optimal smoothing constant-seeking program. The new model, proposed as a collaborative approach, is tested with real-life data gathered from a local manufacturer and also for two industrial cases extracted from literature. In all cases, a significant improvement in forecasting accuracy is achieved.

Background: Recently, there have been an increasing number of literatures on health seeking behavior of different segments of society in the urban and non-urban regions but rarely have these studies emphasized the health care issues related to migrant workers. With this paucity of investigation, this research focuses on the needs and assessment of Bangladeshi workers working in Malaysia and thus contextualizes it to their health care situation.

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<p>Meningkatnya kerusakan lingkungan hidup hutan dan ketidakjelasan solusinya menarik untuk diteliti. Penelitian ini bertujuan untuk mendapatkan jawaban  proses meningkatkan kesadaran masyarakat untuk melestarikan lingkungan hidup. Penelitian ini menggunakan  pendekatan Participation Action Research. Hasil penelitian menunjukkan bahwa proses pengembangan kesadaran melestarikan lingkungan hidup dilakukan  dengan mengembangkan  partisipasi melalui kegiatan kelompok  sebagai media komunikasi untuk   merumuskan  penyebab terjadinya  kerusakan lingkungan hidup, serta menemukan pemecahan masalah melalui pendidikanagama. Hambatan internal dalam mengembangkan kesadaran melestarikan lingkungan adalah latar belakang ekonomi, rendahnya  pemahaman masyarakat terhadap dampak  perusakan lingkungan hidup hutan, dan rendahnya  pemahaman agama.  Faktor eksternal meliputi provokasi dari luar daerah yang mempengaruhi masyarakat melakukan pengerusakan hutan, tingginya nilai jual, dan tersedianya pasar  yang memanfaatkan hasil pencurian. Solusi untuk mengembangkan kesadaran masyarakat adalah meningkatkan sikap humanisme melalui sosialisasi materi pelestarian lingkungan dan  pendidikanagama dengan pendekatan terpadu. </p>

Problem statement:The benefits of easier manufacture of hardened steel components can be substantial in terms of reduced machining costs and lead times compared to the traditional route involving machining of the annealed state followed by heat treatment, grinding/EDM and manual finishing. But machinability of hard material through conventional machining is hindered due to excessive wear of the cutting tools and differently in achieving desired quality of the machined surface. In end milling the cutting tool is not in constant operation and so undergoes a heat cycle during the intermittent cutting. This alternate heating and cooling of the inserts lead to the thermal cracks and subsequently failure of the tool. Approach: This study was conducted to investigate the effect of preheating through inductive heating mechanism in end milling (vertical milling center) of AISI D2 hardened steel (56-62 HRC) by using coated carbide tool inserts. Apart from preheating, two other machining parameters such as cutting speed and feed were varied while the depth of cut was kept constant. Results: Tool wear phenomenon and machined surface finish were found to be significantly affected by preheating temperature and other two variables. Preheating temperature of 335°C coupled with cutting speed of 40 m min −1 , depth of cut of 1.0 mm and feed of 0.02 mm/tooth resulted in a noticeable reduction in tool wear rate leading to a maximum tool life 188.55 min. In addition, cutting speed of 56.57 m min −1 together with feed of 0.044 mm/tooth and depth of cut 1.0 mm at which maximum VMR (9500 mm 3 ) was secured provides a better surface finish with minimum surface roughness 0.25 µm leaving a possibility of skipping the grinding and polishing operations for certain applications. Conclusion/Recommendation: Through the end milling of preheated AISI D2 hardened steel by using TiAlN coated carbide cutting tool it can be concluded that an overall enhanced machinability is achievable by preventing catastrophic damage of the cutting tool at higher levels of feed and cutting speed.

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Purpose The purpose of this paper is to address and solve operational problems of an automotive industry in reaching production target by adopting Maynard Operation Sequence Technique (MOST) as lean and productivity improvement strategies. Design/methodology/approach In the undertaken case of auto-car rear window assembly line, a recurring production shortfall in fulfilling the daily demand is seemingly due to inappropriate work method. Initial observation of the operations led to suspect certain lapses in initiatives to adopt the time standards, to reduce or eliminate non-value added motions, to design suitable aisle and to assign tasks among workstations in a balanced manner. Subsequently an attempt is made to pinpoint the causes of poor performance and the bottlenecks through process flow analysis and time study by applying MOST. The elemental tasks are closely examined for possible reduction of workstation times by choosing efficient work methods with ergonomic features. Thus appropriate hand tools, jigs and fixture with nominal investment are prescribed to incorporate in the assembly works. The operational changes as steered by the MOST application have enhanced the workflow with a shorter cycle time which led to a substantial increase in productivity. Findings The productivity of the assembly line is increased by more than 29 percent from the earlier capacity through the MOST application which is deemed to meet the current level of demand. Originality/value The adopted framework for recognizing the effectiveness of MOST to expose and rectify the flaws in work methods without much investment is expected to be beneficial for a manufacturer in securing the competitiveness.