Victor A. Lifton, Gregory Lifton and Steve Simon
This study aims to investigate the options for additive rapid prototyping methods in microelectromechanical systems (MEMS) technology. Additive rapid prototyping technologies…
Abstract
Purpose
This study aims to investigate the options for additive rapid prototyping methods in microelectromechanical systems (MEMS) technology. Additive rapid prototyping technologies, such as stereolithography (SLA), fused deposition modeling (FDM) and selective laser sintering (SLS), all commonly known as three-dimensional (3D) printing methods, are reviewed and compared with the resolution requirements of the traditional MEMS fabrication methods.
Design/methodology/approach
In the 3D print approach, the entire assembly, parts and prototypes are built using various plastic and metal materials directly from the software file input, completely bypassing any additional processing steps. The review highlights their potential place in the overall process flow to reduce the complexity of traditional microfabrication and long processing cycles needed to test multiple prototypes before the final design is set.
Findings
Additive manufacturing (AM) is a promising manufacturing technique in micro-device technology.
Practical implications
In the current state of 3D printing, microfluidic and lab-on-a-chip devices for fluid handling and manipulation appear to be the most compatible with the 3D print methods, given their fairly coarse minimum feature size of 50-500 μm. Future directions in the 3D materials and method development are identified, such as adhesion and material compatibility studies of the 3D print materials, wafer-level printing and conductive materials development. One of the most important goals should be the drive toward finer resolution and layer thickness (1-10 μm) to stimulate the use of the 3D printing in a wider array of MEMS devices.
Originality/value
The review combines two discrete disciplines, microfabrication and AM, and shows how microfabrication and micro-device commercialization may benefit from employing methods developed by the AM community.
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It is eminently fitting that the Greeks who gave us their word for “speaking fair” should also have supplied us with the ultimate exemplification of its use. They were wont to…
Abstract
It is eminently fitting that the Greeks who gave us their word for “speaking fair” should also have supplied us with the ultimate exemplification of its use. They were wont to refer to the Furies, a group of avenging goddesses, as the Eumenides or “The Fair Ones.” Since the Furies were imagined as having a batlike shape which was adorned with a profusion of snakish hair, they were not fair at all, but rather terrifying, intimidating in the highest degree. To euphemize a phenomenon is to call it something other than what it most particularly is, anything at all provided the new designation is gentler, milder, less offensive, less threatening. It is even possible, as in the case of the Furies renamed Fair Ones, to effect a 180‐degree reversal of meaning.
Within the context of an international conference dealing with global challenges, the Atlantic Community and the outlook for international order organized by Webster University…
Abstract
Purpose
Within the context of an international conference dealing with global challenges, the Atlantic Community and the outlook for international order organized by Webster University, Geneva (Switzerland), to propose an approach to strengthening the international order by reviving the global responsibility to abide by fundamental humanitarian rules.
Design/methodology/approach
The twentieth century presented a very disturbing catalog of violations of humanitarian law. In addressing the main question of the conference, namely “What are the true principles of international order today and do we need new rules and organizing principles in the future?”, the author tackles the issue from the international humanitarian law perspective and suggests various instruments (formal and informal) for enhancing the protection of human dignity.
Findings
A global responsibility to abide by fundamental humanitarian rules may be revived through positive law and judicial mechanisms, but also through a new respect for human life, a return to universal values found in all civilizations, religions and traditions, and through a new humanitarian order based on the core concept of humanity.
Originality/value
This paper suggests that it is through a combination of existing legal and humanitarian instruments, and not just one, that the international order can be strengthened.
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The debate about the future of the death penalty often focuses on whether its supporters are animated by instrumental or expressive values, and if the latter, what values the…
Abstract
The debate about the future of the death penalty often focuses on whether its supporters are animated by instrumental or expressive values, and if the latter, what values the penalty does in fact express, where those values originated and how deeply entrenched they are. In this chapter, I argue that a more explicit recognition of the emotional sources of support for and opposition to the death penalty will contribute to the clarity of the debate. The focus on emotional variables reveals that the boundary between instrumental and expressive values is porous; both types of values are informed (or uninformed) by fear, outrage, compassion, selective empathy and other emotional attitudes. More fundamentally, though history, culture and politics are essential aspects of the discussion, the resilience of the death penalty cannot be adequately understood when the affect is stripped from explanations for its support. Ultimately, the death penalty will not die without a societal change of heart.
Seungmug (Zech) Lee, Jae-Jin Joo, Hye-Rim Kwon, Jae-Seung Lee and John J. Rodriguez
This study aims examine to what extent four variable categories of individual ethical ideology, organizational ethical culture, superior's ethical quality and job satisfaction…
Abstract
Purpose
This study aims examine to what extent four variable categories of individual ethical ideology, organizational ethical culture, superior's ethical quality and job satisfaction (JS) are causally linked to personal (un)ethical behaviors among South Korean police officers.
Design/methodology/approach
With a stratified sampling technique, 687 surveys were collected from 16 major local police headquarters across the nation. The reliability and validity of the variables were checked. The structural equation modeling (SEM) is used to test the hypotheses.
Findings
Idealism, principlism, utilitarianism and JS have a negative influence on unethical behaviors, whereas superior's unethical standards are positively associated with unethical behaviors.
Practical implications
The findings can be applied as a reference to improve ethical framework to promote behaviors by enriching the higher level of personal ethical ideology, superior's ethical quality and principlism and utilitarianism by adding an ethics training course to the continuing education program for all officers and developing further education programs for police leadership to raise ethical awareness and quality.
Originality/value
To the authors' knowledge, the study is among the first studies with four comprehensive categories of relevant variables and adds understanding to (un)ethical behaviors of police officers.
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“We received a memorandum from the Manufactured Foods Division of the Ministry of Food requesting our advice on a proposal to make an Order prescribing maximum limits for the…
Abstract
“We received a memorandum from the Manufactured Foods Division of the Ministry of Food requesting our advice on a proposal to make an Order prescribing maximum limits for the fluorine content of calcium acid phosphate (A.C.P.) sold for use in food, and certain articles containing it. The memorandum stated that two processes are used for the manufacture of A.C.P. In the first process elementary phosphorus is used as the raw material and the product is of a high degree of purity. Something like 80 per cent. of the total output in the country is made in this way. In the alternative process the raw material is rock phosphate and the product is contaminated with compounds of fluorine. We were informed that manufacturers using this process claim that they have been selling A.C.P. containing as much as 3,000 p.p.m. of fluorine for many years without exception being taken by Food and Drugs Authorities. During the last few years these manufacturers have had to use such rock phosphates as have been available and no doubt the resulting A.C.P. has often been more heavily contaminated than it was before the war. We were also informed that the possibility of harmful contamination of foods with fluorine has been giving concern to Public Health Authorities. From 1942, Food and Drugs Authorities brought proceedings in certain cases under the Food and Drugs Act, 1938, in respect of baking powder or articles containing it contaminated with fluorine, but they failed in some of them to obtain conviction. In August, 1943, the Society of Public Analysts and Other Analytical Chemists, which had been giving consideration to this question, issued a statement recommending that no action should be taken under the Food and Drugs Act where the following proportions of fluorine, however combined, were not exceeded: In acid phosphates, 200 parts per million; in baking powder, 70 parts per million; in golden raising powder, 50 parts per million; in self‐raising flour, cake mixtures and like compositions, 5 parts per million. Nevertheless, in the absence of a legal standard it is difficult to convince a Court that where any of these proportions is exceeded an offence has been committed. In at least one case subsequently a Food and Drugs Authority failed to secure a conviction and in general Authorities appear to have been reluctant to take action. In view of this unsatisfactory situation, several Authorities have proposed that limits should be defined by Regulation. Manufacturers have also urged that steps should be taken to clarify the position, and at our invitation the manufacturers submitted a report of work carried out on their behalf by H.E. Archer, M.R.C.S., L.R.C.P., F.R.I.C, and B. Leech, M,A., F.R.I.C. In this report it was suggested that: (i) In the combination in which it occurs in food products after aerating ingredients have interacted, fluorine is insoluble in normal gastric juice even when the acidity approaches the upper limit of normality. Further, phosphates present in a food after interaction of the aerating ingredients buffer the gastric juice at a pH on the alkaline side of neutrality so that any fluorine present is insoluble and unabsorbable. (ii) Within the limits of experimental error, any fluorine ingested in the form of baking powder containing contaminated A.C.P. after interaction of the aerating ingredients is excreted completely in the faeces. The report was discussed at a meeting between the manufacturers representatives and the committee. We pointed out that since the experiments described related to only one adult, who was on a high milk diet, the results could not be accepted as evidence of what might take place in the case of other persons, especially children, taking a more varied diet. Dr. Archer, however, indicated that the case for the harmlessness of fluorine rested not merely on the experiments described in the report, which he recognised as being chiefly of a confirmatory nature, but also on the fact that mottling of teeth is rarely or never found except where the water supply is known to be contaminated. He asserted that this condition was a highly sensitive indicator of fluorine absorption, and since A.C.P. contaminated with fluorine was extensively used, the absence of mottling of teeth showed that fluorine was not absorbed from A.C.P. It was further asserted that even if widespread mottling had occurred, the condition was to be regarded merely as a cosmetic disability and not as evidence of the toxicity of fluorine. Reference was made to work by Roholm stated to show that cryolite workers enjoyed excellent health and that comparatively large amounts had to be ingested daily for many years before any symptoms developed. It was stated further that investigations in this country had failed to reveal any radiological evidence of skeletal changes in either adults or children with mottled teeth, except in under‐nourished children from bad homes. The manufacturers' case therefore was the fluorine was not absorbed from A.C.P., and even if absorbed was harmless. On the other hand, our attention was drawn to various statements in medical literature suggesting that mottling of teeth is more common than usually supposed. Moreover, with other toxic elements, for example lead, almost complete excretion in the faeces does not necessarily justify the assumption that oral ingestion is harmless. We felt that the arguments advanced by the manufacturers could not be dismissed without further investigation and that their validity could be assessed only by persons having the requisite physiological and toxicological knowledge. The following questions were accordingly addressed to the Medical Research Council: (1) Is there any authoritative evidence that injury to human health has resulted from the absorption over lengthy periods of small amounts of fluorine from food other than water? (2) Is it true that widespread mottling of teeth in the community does not occur? (3) If the answer to question (2) above is in the affirmative, can the absence of widespread mottling be accepted as evidence that absorption does not occur at all or not to any harmful extent? (4) Having regard to the available evidence, including that advanced in the report prepared by Dr. Archer and Mr. Leech, is it in the opinion of the council desirable that an Order should be made limiting the amount of fluorine in calcium acid phosphate? (5) If the answer to question (4) is in the affirmative, what limit should be imposed? The following specific answers were given to these questions: (1) Answer is no, because so far no one would have recognised the effects of such ingestion; analysts have only been interested in fluorine determinations in recent years and pathologists have not clearly established the criteria of milder forms of chronic fluorosis. (2) Answer is no: in any case mottling of enamel is not the most suitable indication of fluorine ingestion except by the water supply. (3) Animal experiments have shown that fluorine is ingested by pigs, rabbits, rats, cattle, sheep and dogs from food, pasture and rock phosphates. Widespread fluorosis occurs in cattle and humans in Algeria, one of the regions from which much rock phosphate is obtained. The ingestion of fluorine from rock phosphates, besides producing the well‐known bone changes, produces in different species different effects, including pathological changes in the mucous membrane of the alimentary canal, and nephrosis. (4) Yes, an Order should be made. (5) The limit for calcium acid phosphate should be 300 p.p.m. In recommending that the limit be somewhat higher than was suggested by the Society of Public Analysts and Other Analytical Chemists, the Council stated that in their view a limit of 300 p.p.m. would still be safe having regard to the proportion of A.C.P. which is used in foods containing it. In amplification of these answers the Council informed us that in their opinion it is essential that a limit be set for the amount of fluorine permissible in any material used in food production and suggested that the safest procedure would be to prohibit the use of A.C.P. made from rock phosphate for food purposes. The view was expressed that since the effects of fluorine are cumulative, absorption from the alimentary canal could only be proved or disproved by determining the urinary excretion of fluorine during administration over a period. The argument that the absence of mottling of teeth showed that absorption does not occur was criticised on various grounds. In addition, it was suggested that Roholm's monograph on fluorine poisoning, the recent work of Ockerse in South Africa and Shortt in India, and reports from industries using fluorine compounds, all tended to show that fluorine was a potentially toxic contaminant. In view of the possible effect such an Order would have on certain manufacturers we felt it desirable to acquaint ourselves more fully with the grounds underlying the Council's recommendation, and Dr. Margaret Murray, who had advised the Council on the matter, kindly attended a meeting of the Committee to provide further information. Dr. Murray suggested that it was not justifiable to base any opinion on a short term experiment, since, for example, in the parts of India where fluorosis is endemic, the effects may not become evident for 25 to 30 years. She considered that the balance found by Dr. Archer and Mr. Leech in the intake and excretion of fluorine by their patient must have been largely fortuitous because, apart from the difficulty of accurately determining small quantities in the excreta, fluorine is cumulative and the fluorine excreted on one particular day is not necessarily that ingested the previous day. She agreed that small amounts, in drinking water, had a beneficial effect in tending to prevent caries, but was nevertheless of the opinion that this did not justify the ingestion of fluorine in larger quantities, or from other sources. The further evidence provided by Dr. Murray may be summed up by saying that fluorine, if absorbed in small quantities over a sufficient period of time, can produce gross lesions of bone; there is abundant evidence from animal experiments and analyses of human bones that fluorine can be cumulatively absorbed; and there is radiological evidence that a mild spondylitis occurs in some children living in areas where the drinking water contains fluorine, although it is possible that the affection occurs only in those children whose nutritional state is poor. We record our appreciation of the assistance rendered by the Medical Research Council and by Dr. Murray. In view of the unquestionable harmfulness of large amounts of fluorine, and of the cumulative effect of small doses, we feel that the risk to the public health from the repeated ingestion of small amounts of fluorine is too serious to be ignored, and that an Order should be made prescribing maximum limits for the contamination.”
Danna Tang, Yushen Wang, Zheng Li, Yan Li and Liang Hao
The low-temperature sintering of silica glass combined with additive manufacturing (AM) technology has brought a revolutionary change in glass manufacturing. This study aims to…
Abstract
Purpose
The low-temperature sintering of silica glass combined with additive manufacturing (AM) technology has brought a revolutionary change in glass manufacturing. This study aims to carry out in an attempt to achieve precious manufacturing of silicate glassy matrix through the method of slurry extrusion.
Design/methodology/approach
A low-cost slurry extrusion modelling technology is used to extrude silicate glassy matrix inks, composed of silicate glass powder with different amounts of additives. Extrudability of the inks, their printability window and the featuring curves of silicate glassy matrix are investigated. In addition, the properties of the low-temperature sintering green part as a functional part are explored and evaluated from morphology, hardness and colour.
Findings
The results showed that the particle size was mainly distributed from 1.4 µm to 5.3 µm, showing better slurry stability and print continuity. The parameters were set to 8 mm/s, 80% and 0.4 mm, respectively, to achieve better forming of three-dimensional (3D) samples. Besides, the organic binder removal step was concentrated on 200°C–300°C and 590°C–650°C was the fusion bonding temperature of the powder. The hardness values of 10 test samples ranged from 588 HL to 613 HL, which met the requirements of hard stones with super-strong mechanical strength. In addition, the mutual penetration of elements caused by temperature changes may lead to a colourful appearance.
Originality/value
The custom continuous AM technology enables the fabrication of a glass matrix with 3D structural features. The precise positioning technology of the glass matrix is expected to be applied more widely in functional parts.
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Officially, of course, the world is now post-imperial. The Q’ing and Ottoman empires fell on the eve of World War I, and the last Leviathans of Europe's imperial past, the…
Abstract
Officially, of course, the world is now post-imperial. The Q’ing and Ottoman empires fell on the eve of World War I, and the last Leviathans of Europe's imperial past, the Austro-Hungarian and Tsarist empires, lumbered into the grave soon after. Tocsins of liberation were sounded on all sides, in the name of democracy (Wilson) and socialism (Lenin). Later attempts to remake and proclaim empires – above all, Hitler's annunciation of a “Third Reich” – now seem surreal, aberrant, and dystopian. The Soviet Union, the heir to the Tsarist empire, found it prudent to call itself a “federation of socialist republics.” Mao's China followed suit. Now, only a truly perverse, contrarian regime would fail to deploy the rhetoric of democracy.