Search results

Critical processing steps of COB manufacturing, as implemented at Epitek, are reported. They include testing of incoming boards, cleaning, bonding parameters, bonding defects and statistical process control.

A set of rules is presented for printing thick film resistors, whose implementation minimises losses due to resistors firing too high or too low, and also results in the shortest possible set‐up times. To the best of the authors' knowledge, some of the concepts and relations reported here are nowhere to be found spelled out in the published literature, let alone presented in quantitative form. One example is the relationship between sheet resistance vs resistor length curves and the mesh/emulsion of the screen used to obtain such curves. Another example is the relationship between the choice (or lack of it) of resistors used to set up thickness at the beginning of a print, and the spread in resistance values. Then there are better known relationships, like the dependence of thickness on resistor width or print direction—still no quantitative data are available and the potential relevance of these effects is generally not appreciated. Long set‐up times and yield losses need not exist, as they arise from non‐rigorous printing rules which call for a standard dry thickness (usually 25±3 µm) regardless of resistor dimensions, print direction and ink jar value, and which only call for a range of screen mesh/emulsion values, rather than for specific ones. In fact, for any given sheet resistance vs resistor length curve, only one choice of screen mesh/emulsion and resistor thickness is logically possible. Also reported are experimental data relating resistor thickness to resistor length as a function of screen mesh/emulsion, resistor width and print direction as well as data on sheet resistance as a function of resistor dry thickness. Finally, results from thirty‐eight production runs are reported and discussed.

Hybrid manufacturers are uncertain as to whether laser‐drilled holes on 96% alumina are suitable for mixed‐bonded thick film conductor metallisation, or whether they require further treatment before metallisation if reliable circuitry is to be produced. Moreover, although the metallisation of holes on ceramic through the use of screen printed thick films is fairly common in the hybrid industry, this paper shows that published information on this topic is scant, at times contradictory, and, because of proprietary constraints, generally of little use. The authors report on an extensive study in which both as‐laser‐drilled holes and thermally‐treated laser‐drilled holes are metallised using a mixed bonded Pd‐Ag conductor paste. Both encapsulated and non‐encapsulated metallised holes are then subjected to various accelerated life tests, followed by ‘power‐up’ tests to the extreme of circuit destruction. An account is also given of a printing set‐up which allows volume production of printed through‐holes without the need for special skill or attention on the part of the printing operator.

Improving the use of annotations in lecture recordings.

Requirements analysis with scenario based design (SBD) on focus groups.

These seven points have been extracted from the feedback of the focus groups: (1) Control of the annotation feature (turn on/turn off). (2) An option to decide who is able to see their comments (groups, lecturer, friends). (3) An easy and paper-like experience in creating a comment. (4) An option to discuss comments. (5) An option to import already existing comments. (6) Color-coding of the different types of comments. (7) An option to print their annotations within the context of the recording.

The study was performed to improve the open-source lecture recording system Opencast Matterhorn.

Annotations can help to enable the students that use lecture recordings to move from a passive watching to an active viewing and reflecting.

The current methods for inspecting tall or deep structures such as towers, chimneys, silos, and wells suffer from certain constraints. Manual and assisted inspection methods including humans, drones, wall climbing robots, and others are either costly, have a limited operation time, or affected by field conditions, such as temperature and radiation. This study aims to overcome the presented challenges through a teleoperated soft continuum manipulator capable of inspecting tall or deep structures with high resolution, an unlimited operation time and the ability to use different arms of the manipulator for different environments and structure sizes.

The teleoperated manipulator uses one rotary and two tendon actuators to reach and inspect the interior of a tall (or deep) structure. A sliding part along the manipulator’s body (arm constrainer and tendon router) induces a variable-length bending segment, allowing an inspection camera to be placed at different distances from the desired location.

The experiments confirmed the manipulator’s ability to inspect different locations in the structure’s interior. The manipulator also demonstrated a submillimeter motion resolution vertically and a 2.5 mm per step horizontally. The inspection time of the full structure was 48.53 min in the step-by-step mode and was calculated to be 4.23 min in the continuous mode.

The presented manipulator offers several design novelties: the arm’s thin-wide cross-section, the variable-length bending segment in a fixed-length body, the external rolling tendon routing and the ability to easily replace the arm with another of different material or dimensions to suite different structures and environments.

Mechanical properties of 100% polyester and polyester-viscose (P/V) blended yarns produced from polyester fibres which vary in denier and cross-sectional shape have been analyzed. It is observed that fibre fineness and cross-sectional shape play a significant role in the translation of fibre properties to the respective yarn properties. As the fibre linear density decreases, fibre strength translation efficiency increases. In the case of trilobal fibre, translation efficiency is observed to be lower, but yarn breaking elongation is higher in comparison to the corresponding circular fibre. Scalloped oval fibre contributes more towards yarn strength and elongation versus the equivalent circular and tetraskelion fibres. In the P/V blended form, a decrease in yarn tenacity does not affect fibre fineness, but is substantially influenced by changes in the fibre profile. Contribution of broken viscose fibres (comparatively weaker component) at the point of actual breaking of yarn, i.e. Z-value, is altered depending on the polyester fibre profile, which is higher in trilobal and scalloped oval fibres in comparison to the corresponding circular ones, but the role of fibre linear density in this regard is rendered insignificant.

This document presents the study of a one‐dimensional thermal inclinometer based on free convection.

A micromachined one is used. The sensitivity of the sensor is optimized in a close chamber containing CO2 gas under pressure.

By using this type of sensor in a close chamber containing CO2 gas under pressure, the sensitivity increase and the response time decrease when the pressure increase. High resolution will be achieved.

High shock reliability.

Measuring μg acceleration.

Low cost production.

This article describes a new humidity sensor using the technique of differential thermal analysis (DTA). The energy of water vaporisation is estimated via the measurement of the Seebeck voltage of miniature thermocouples used in differential mode on a Peltier module causing condensation from the ambient air. This sensor uses the sensitivity of alloys V2VI3 containing [Bi, Te, Sb, Se], 400‐440μV.K^–1. Experimental measurements have been performed in a climatic chamber at constant temperature. The time variation of the differential Seebeck voltage with relative humidities H_R varying from 10 to 90 per cent makes it possible to identify with precision the point of water evaporation. For each value of the relative humidity, it is directly a function of the condensate mass. The integration of these curves over time makes it possible to calculate the energy of vaporisation and the condensate mass.

The purpose of this paper is to develop an insight into the prevalent quality and supply chain practices adopted in the contemporary Indian manufacturing industry, and compare business performance measurements between transfusion of total quality management (TQM)–supply chain management (SCM) companies and only SCM implementing companies.

To meet the goals of this work, i.e., to ascertain contributions made by TQM–SCM practices, a reasonably large number of Indian manufacturing organizations have been extensively surveyed, through a specially designed TQM–SCM questionnaire. And the design of TQM–SCM questionnaire has been finalized through extensive literature review. Finalized TQM–SCM questionnaire was sent to around 720 industries that are implementing TQM and SCM with other related lean manufacturing practices.

The leading Indian manufacturing organizations have taken proactive initiatives to effectively improve the manufacturing by transfusing various lean manufacturing philosophies like TQM, SCM, TPM, 5S, Six Sigma, etc., for realizing enhanced manufacturing performance. The study reveals that Indian entrepreneurs have been reasonably successful in improving the business performances in the organizations by implementing combination of TQM and SCM, as TQM support to SCM is much effective and this improvement initiative has significantly contributed toward enhancing the overall manufacturing performance.

Synergy of TQM and SCM in the context of Indian manufacturing industry has been proved beneficial in terms of competitive image as well as business performance. Therefore, the whole Indian manufacturing entrepreneurs must continue to make an earnest effort in their endeavour to realize enhanced competitiveness through synergizing different business improvement initiatives. A major implication is that only SCM implementing companies should develop their supply chain through synergy of TQM–SCM after analyzing the business environment and their future plans.

Much of the attention has been given to TQM practices and SCM practices, and very few studies have been undertaken to integrate TQM and SCM practices. But as far as the authors know till now there is no study undertaken to analyze synergy status of TQM and SCM and then comparing with only SCM implementing companies in India for medium- and large-scale manufacturing class. Therefore, this study compares the transfusion of TQM–SCM with only SCM companies and can be, thus, treated as filling a gap in the extant literature. Therefore, the findings of this research paper will contribute to future research.

The purpose of this paper is to develop a method to select the best alternative in a multi‐criteria decision making (MCDM) environment when the decision is taken by a group of members in an uncertain environment.

In this paper, Fuzzy Preference Ranking Organization Method for Enrichment Evaluations (Fuzzy PROMETHEE) technique has been used for MCDM problems. The team of decision makers is constituted to integrate their opinion. The analysis is done using Geometrical Analysis for Interactive Aid (GAIA) plane, available in Decision Lab 2000 software, which provides valuable help in understanding the conflicts among criteria.

The selection of best alternative is done on the basis of generally conflicting criteria. Fuzzy PROMETHEE technique has been proposed and the same is demonstrated using Decision Lab 2000 software. This software can be used for as many criteria as possible and also in a fuzzy environment, where the crisp data for criteria comparison are not available. It is found that the analysis of the results becomes very easy and effective with this software. A case study is conducted for a cement company to select the logistic service providers (LSPs) to demonstrate its ease and effectiveness of use.

The research provides a model to choose the best alternative using Decision Lab 2000 software for Fuzzy PROMETHEE technique. The proposed methodology can be used in a fuzzy environment with ease and effectiveness. In the competitive scenario, this could help the industry in prompt and efficient decision making in MCDM problems.