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1 – 10 of 550An important disadvantage of conducting adhesives is their inferior heat conductivity when compared with soft solder such as Sn60Pb40. Thermal simulations, however, show that, by…
Abstract
An important disadvantage of conducting adhesives is their inferior heat conductivity when compared with soft solder such as Sn60Pb40. Thermal simulations, however, show that, by using thinner layers of adhesive than of solder, the module's thermal resistance does not increase greatly. Test modules with four different silver filled epoxy adhesives and tin/lead solder were manufactured. These test modules contained power diodes, 30 A, 1000 V, die bonded onto Ag/Pt thick film conductors on alumina. The die bond adhesive layer thicknesses were typically 30 or 40 μm. For die bond solder layers the thickness was 90 μm. The alumina substrates were connected to 3 mm thick copper plates with filled epoxy or silicone adhesive. The thickness of these layers was 150 μm or 50 μm, respectively. Thermal resistance of the structures was measured. The results showed that good adhesion between joined surfaces is essential for optimised heat flow. The heat conductivity of an adhesive was only a secondary factor affecting the structure's thermal resistance. When the adhesive joint is of good quality, the replacement of solder with conductive adhesives does not increase the module's thermal resistance any more than as shown by the simulations. It should, however, be remembered that the printing of thin (< 20 μm) uniform layers is not always possible.
The analyses of trends in prosecutions under the Food and Drugs Act, 1955 and the various regulations, which we have prepared every two years or so, covering a three‐month period…
Abstract
The analyses of trends in prosecutions under the Food and Drugs Act, 1955 and the various regulations, which we have prepared every two years or so, covering a three‐month period, have been so much appreciated by readers, both in the administration and the industry itself, that we have prepared a more extended survey, covering the whole of 1966. The survey, as before, takes the form of a month‐by‐month analysis of reports of legal proceedings received by us from all parts of the country, and as formerly records the prosecutions under similar groupings; cases under Section 2, subdivided into those relating to compositional offences, the presence of foreign bodies and those relating to mouldy food: false description cases under Section 6 of the Merchandise Marks Acts; Section 8, the unfit food provision, also subdivided with special categories for foreign bodies and mouldy food; Section 32, milk cases; cases under the Food Hygiene Regulations, 1960, with smoking offences separated; the Milk and Dairies Regulations, consisting almost entirely of prosecutions under Reg. 27, Meat Regulations, Preservative Regulations, Colouring Matter in Food Regulations, etc.
This paper is concerned with the obstacles of educational reform in a racial climate and the acceptance of Barack Obama as the 44th president of the United States.
Abstract
Purpose
This paper is concerned with the obstacles of educational reform in a racial climate and the acceptance of Barack Obama as the 44th president of the United States.
Design/methodology/approach
As a result, while the president’s positions on educational reform are important, the question still remains; can the majority of Whites support an agenda coming from a Black president? Moreover, as a Black man, can the president really be “allowed” to be a “representative” of all of the people? Do many people think that the election of Mr. Obama ushered in a “postracial” society; in that he is the living testament that we no longer need to focus on social justice, civil rights, and educational reform, especially for underperforming minority schools? Is race a factor among Whites and Blacks regarding President Obama’s approval ratings? How much success can any president expect to have when a significant majority of the population is resistant to his vision of “change?”
Findings
Based upon these lingering questions, the issue of race has been and will remain a factor in the Obama presidency that no other president has had to contend. Obfuscation, control, and fear appear to be the raison d’être regarding a strategy of resistance toward President Obama and his interest in “change.” These are the reasons why President Obama’s time is significantly spent on negotiating racial obstacles to change.
Originality/value
The goal of this paper is to provide a sociological and psychological context within a historical framing to understand obstacles to change faced by President Barack Hussein Obama.
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The distribution function in a supply chain is an important internal service function for any firm, and has been increasingly recognized as playing a strategic role in achieving…
Abstract
The distribution function in a supply chain is an important internal service function for any firm, and has been increasingly recognized as playing a strategic role in achieving competitive advantage. This paper proposes improving the distribution function of the supply chain by employing hub‐and‐spoke network designs. Such designs have proven to be effective with third party logistics carriers such as Federal Express, UPS, Norfolk Southern, and Yellow Freight. Several models and heuristic solution techniques have been introduced in the literature in the past ten years. However, the performance of such heuristics, under different transportation environments, has not been examined. This paper acts as a first step in this direction. The performance of two heuristics to solve a hub‐and‐spoke network is compared against the performance of an optimal technique, for various configurations of data. With the results of this study, business managers can, by analyzing the structure of their data, assess the “risk” associated with applying one of the two heuristics. Heuristic developers can also exploit the results of this study to give them insight into areas where heuristics can be developed or strengthened in order to give rise to more robust heuristics.
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Conductive adhesives (CAs) have been with us for a number of years and have found use in a variety of applications. More recently pressure from environmentalists has led to a…
Abstract
Conductive adhesives (CAs) have been with us for a number of years and have found use in a variety of applications. More recently pressure from environmentalists has led to a reappraisal of the potential of the materials to replace solders in mainstream assembly operations. In this respect they have the advantages that they do not contain lead and do not use fluxes. At present, however, there is no substitute for flow soldering operations which still account for a substantial part of the assembly market. There also appear to be serious grounds for concern regarding the reliability of adhesive joints. In particular, recent reports suggest that their resistance to mechanical shock may be unsatisfactory. In the light of these drawbacks it seems likely that CAs will continue to find niche applications, where their particular properties give them advantages, but that soldering will continue to be the dominant technology for PCB assembly for the foreseeable future.
Most countries seek to impose control on the chemical treatment of both human and animal food. Some, such as the U.S.A., attempt it by highly detailed regulations, in terms most…
Abstract
Most countries seek to impose control on the chemical treatment of both human and animal food. Some, such as the U.S.A., attempt it by highly detailed regulations, in terms most orthodox and almost psychically specific, which seem most complicated compared with our own simplified food ordinances; other countries, such as many of the newer states, treading cautiously in their virgin fields of law‐making, pass broad, enabling laws, leaving details to be filled in later. Although the object is the same in all countries, it is nothing short of amazing how the pattern of legislation manages to be so divergent, and applied for reasons that are not always apparent. In published regulations and laws, there would seem to be less intent on making a country's food exports conform to the legislative requirements of importing countries than in prescribing standards for its home products; the end results have produced food law chaos, rarely seen in other branches of law. A notable exception, the only one, to these irregular developments, and with particular reference to food additive control, are the common decrees and directives of the European Economic Community, representing the six Common Market countries. Its Council prescribes quality standards for individual foods, specific purity standards for preservatives and other additives which may be used for human consumption, and although this standardisation is only beginning, it deserves study, especially the manner in which the community regulations are enforced.
Democratic candidate Barack Obama campaigned for the office of President of the United States on a message of hope and change. Included in this message was an avowed commitment to…
Abstract
Democratic candidate Barack Obama campaigned for the office of President of the United States on a message of hope and change. Included in this message was an avowed commitment to fighting for equality and social justice. This chapter evaluates the Obama administration's record on social justice issues from a black feminist perspective. I find that although the administration has made some notable achievements, the universalist paradigm from which it operates may cause policymakers to overlook multiply oppressed groups. It might likewise blind them to the processes that generate and maintain social inequality. I argue that the results could hinder Obama from succeeding with much of his social justice agenda. I conclude by discussing how examining inequality through a black feminist prism would enable the Obama administration to speed up its program and develop and implement more effective policies. Finally, I also recommend a social justice project that might help the president create a legacy that will promote his goals long after he leaves office.
Julie Cox and Angi Martin
Assessing learning outcomes for students who are d/Deaf or hard of hearing presents ongoing challenges given the largely verbal nature of classrooms and the presentation of…
Abstract
Assessing learning outcomes for students who are d/Deaf or hard of hearing presents ongoing challenges given the largely verbal nature of classrooms and the presentation of information. Educators should carefully consider several factors when assessing their students who are d/Deaf or hard of hearing. Those factors include, but are not limited to: the format of the assessment, the format in which the student is expected to respond, classroom acoustics, as well as how to continue monitoring learning outcomes based on classroom instruction.
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This study discusses the influence of logistical immediacy on logistics service providers' (LSPs’) business. Specifically, its role in the face of the emerging business scenario…
Abstract
Purpose
This study discusses the influence of logistical immediacy on logistics service providers' (LSPs’) business. Specifically, its role in the face of the emerging business scenario (e-commerce, disruptive technologies, and new models of logistical services) is examined.
Design/methodology/approach
As logistical immediacy is a nascent topic, this study utilizes a systematic literature review focusing on academic articles from the last five years related to logistical outsourcing to understand the changes imposed by logistical immediacy on LSPs.
Findings
The impact of transformations arising from an increasingly digital virtual world (DVW) on LSPs is contextualized. A theoretical view of the factors affecting LSPs' shift towards more immediate operations is presented, and how logistical immediacy impacts LSPs is discussed. Finally, a research agenda is presented as the study's main contribution.
Research limitations/implications
Due to the timeframe chosen, the restriction to a single database (Scopus), the specific search terms used related to LSPs, and limiting the search parameters to operations management, some relevant work may have been overlooked.
Practical implications
The article help LSPs' and contracting companies' managers to understand the influence of the immediacy expected in logistics operations. Possible logistics services trends and how they may impact companies are discussed.
Originality/value
This is one of the first articles in the area of operations and supply chains that addresses the issue of logistical immediacy and its impact on LSPs.
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John McLaughlin, Jaideep Motwani, Manu S. Madan and A. Gunasekaran
To succeed in today’s global marketplace, organizations are looking at streamlining their supply chain through the successful deployment of information technology. This paper, by…
Abstract
To succeed in today’s global marketplace, organizations are looking at streamlining their supply chain through the successful deployment of information technology. This paper, by means of a case study, discusses how a manufacturing company implemented a transportation planning and optimization system to enhance their downstream supply chain operations. The application development framework is used to analyze the implementation process. The findings of this case study will benefit companies seeking to create a competitive advantage in the marketplace through advanced physical distribution capabilities.
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