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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.

Transport shapes the health of urban populations. It can support healthy behaviours such as participation in regular physical activity and access to community connection. Transport systems can also have major negative impacts on health. For example, through air pollution from fossil fuel-based modes of travel, the risk of injury and death from transport related collisions, and in the way sedentary modes of travelling can contribute to less physically active lifestyles.

This chapter considers the long-term impact of the pandemic on a series of well-researched transport-related health outcomes. It first describes the established connections between transport and health. It then considers the future implications of three potential pandemic-induced shifts: the increased uptake of working from home (WFH); decreased usage of public transport and increased interest in walking and cycling in the local neighbourhood. The impacts of these shifts on the transport-health nexus are then discussed, revealing both positive and negative outcomes. The authors conclude by providing policy recommendations to mitigate possible negative outcomes and strengthen the positive consequences into the future.