328,014 research outputs found
Optimal Estimates for the Electric Field in Two-Dimensions
The purpose of this paper is to set out optimal gradient estimates for
solutions to the isotropic conductivity problem in the presence of adjacent
conductivity inclusions as the distance between the inclusions goes to zero and
their conductivities degenerate. This difficult question arises in the study of
composite media. Frequently in composites, the inclusions are very closely
spaced and may even touch. It is quite important from a practical point of view
to know whether the electric field (the gradient of the potential) can be
arbitrarily large as the inclusions get closer to each other or to the boundary
of the background medium.
In this paper, we establish both upper and lower bounds on the electric field
in the case where two circular conductivity inclusions are very close but not
touching. We also obtain such bounds when a circular inclusion is very close to
the boundary of a circular domain which contains the inclusion. The novelty of
these estimates, which improve and make complete our earlier results published
in Math. Ann., is that they give an optimal information about the blow-up of
the electric field as the conductivities of the inclusions degenerate.Comment: 26 page
Effect of Diethylenetriamine and Triethylamine sensitization on the critical diameter of Nitromethane
In this work, the critical diameter for detonation was measured for Nitromethane (NM) sensitized with two different amines: Diethylenetriamine (DETA) and Triethylamine (TEA). The critical diameter in glass and polyvinylchloride tubes is found to decrease rapidly as the amount of sensitizer is increased, then increase past a critical amount of sensitizer. Thus the critical diameter reaches a minimum at a critical concentration of sensitizer. It was also found that the critical diameter is lower with DETA than with TEA
On Charlie Gard: Ethics, Culture, and Religion
The 2017 story of Charlie Gard is revisited. Upon the British High Court’s ruling in favor of the physicians that the infant should be allowed to die without the experimental treatment, the view of the public as well as the opinions of bioethicists and Catholic bishops are divided, interestingly along with a cultural line. American bioethicists and Catholic bishops tend to believe that the parents should have the final say while British/European bioethicists and Catholic bishops in general side with the court’s decision. The paper explores the place of culture in bioethical reasoning between the UK/Europe and the US while claiming that cultural differences are more important than geopolitical or religious differences to understand the bioethical positions of a group. In addition, the authors introduce a decision-making program for handicapped neonates which is developed by the American Jesuit Bioethicist, Richard McCormick, and modified further by the contemporary American Jesuit Bioethicist, Peter A. Clark, in an attempt to see if the program’s normatizing categories can contribute to the culture-laden ethical discussions on Charlie’s case. However, it is admitted that the McCormick-Clark device is borne out of the American and Catholic theological context
Equipping Police with Naloxone Spray and Decriminalizing All Opioid Use in the U.S.: An Ethical Analysis
The number of police departments carrying Narcan keeps increasing at a fast pace throughout the U.S., as it is considered an effective measure to fight the opioid epidemic. However, there have been strong oppositions to the idea of the police Narcan use. Still, in 2018, the nation is debating about it. Though not clearly visible to the public, there are important ethical arguments against the police Narcan use which necessarily involve understanding of the ethical roles and responsibilities of police as the law enforcement agency and apprehension of the moral status of a non-therapeutic opioid use. The authors of the paper investigate, primarily, the existing ethical controversies surrounding the police Narcan use while touching upon the issue of the decriminalizing drug policy in the U.S. The authors conclude that the police can carry and administer Narcan without self-contradiction and that the policymakers’ investigation on the drug decriminalization policy should begin with the understanding of the “common morality” of the American public, the ethical view shared and practiced by the greatest number of people
Why Naming Disease Differs From Naming Illness
Addressing the question of how medicine should engage with people who consider their clinical disease condition to be importantly constitutive of their identity, this article focuses on one group—advocates for the fat acceptance (FA) or body positivity movement in American society. Drawing on philosophical analysis, I try to show that FA and physician communities represent different traditions within the larger culture and that whether obesity should be considered a disease is a culture battle. I argue that diseases (medical) and illnesses (cultural) are 2 different designations of clinical symptoms and that both disease and illness designations can change over time or be uncertain
On Charlie Gard: Ethics, Culture, and Religion
The 2017 story of Charlie Gard is revisited. Upon the British High Court’s ruling in favor of the physicians that the infant should be allowed to die without the experimental treatment, the view of the public as well as the opinions of bioethicists and Catholic bishops are divided, interestingly along with a cultural line. American bioethicists and Catholic bishops tend to believe that the parents should have the final say while British/European bioethicists and Catholic bishops in general side with the court’s decision. The paper explores the place of culture in bioethical reasoning between the UK/Europe and the US while claiming that cultural differences are more important than geopolitical or religious differences to understand the bioethical positions of a group. In addition, the authors introduce a decision-making program for handicapped neonates which is developed by the American Jesuit Bioethicist, Richard McCormick, and modified further by the contemporary American Jesuit Bioethicist, Peter A. Clark, in an attempt to see if the program’s normatizing categories can contribute to the culture-laden ethical discussions on Charlie’s case. However, it is admitted that the McCormick-Clark device is borne out of the American and Catholic theological context
U-health expert system with statistical neural network
Ubiquitous Health(U-Health) system witch focuses on automated applications that can provide healthcare to human anywhere and anytime using wired and wireless mobile technologies is becoming increasingly important. This system consists of a network system to collect data and a sensor module which measures pulse, blood pressure, diabetes, blood sugar, body fat diet with management and measurement of stress etc, by both wired and wireless and further portable mobile connections. In this paper, we propose an expert system using back-propagation to support the diagnosis of citizens in U-Health system
Third-order Intermodulation Reduction in Mobile Power Amplifiers by the First Stage Bias Control
In this paper, the third order intermodulation distortion (IMD3) of three-stage power amplifier (PA) is analyzed using the Volterra series. The analysis explains how the total IMD3 of the three-stage power amplifier can be reduced by the first-stage bias condition. The three-stage PA, which is fabricated using InGaP/GaAs hetero-junction bipolar transistor (HBT), operates with an optimized first driver stage bias for higher P1dB and good gain flatness. The power amplifier has been designed for 1626.5 MHz~1660.5 MHz satellite mobile communications. With π/4 DQPSK modulation signals, this PA can deliver a highly linear output power of 33 dBm from 3.6V supply voltage. At 33 dBm output power, it shows a gain of 31.9 dB, a power-added efficiency (PAE) of 39.8%, an adjacent channel power ratio (ACPR) of -28.2 dBc at a 31.25 KHz offset frequency
Micro-electroforming metallic bipolar electrodes for mini-DMFC stacks
This paper describes the development of metallic bipolar plate fabrication
using micro-electroforming process for mini-DMFC (direct methanol fuel cell)
stacks. Ultraviolet (UV) lithography was used to define micro-fluidic channels
using a photomask and exposure process. Micro-fluidic channels mold with 300
micrometers thick and 500 micrometers wide were firstly fabricated in a
negative photoresist onto a stainless steel plate. Copper micro-electroforming
was used to replicate the micro-fluidic channels mold. Following by sputtering
silver (Ag) with 1.2 micrometers thick, the metallic bipolar plates were
completed. The silver layer is used for corrosive resistance. The completed
mini-DMFC stack is a 2x2 cm2 fuel cell stack including a 1.5x1.5 cm2 MEA
(membrane electrode assembly). Several MEAs were assembly into mini-DMFC stacks
using the completed metallic bipolar plates. All test results showed the
metallic bipolar plates suitable for mini-DMFC stacks. The maximum output power
density is 9.3mW/cm2 and current density is 100 mA/cm2 when using 8 vol. %
methanol as fuel and operated at temperature 30 degrees C. The output power
result is similar to other reports by using conventional graphite bipolar
plates. However, conventional graphite bipolar plates have certain difficulty
to be machined to such micro-fluidic channels. The proposed
micro-electroforming metallic bipolar plates are feasible to miniaturize DMFC
stacks for further portable 3C applications.Comment: Submitted on behalf of EDA Publishing Association
(http://irevues.inist.fr/handle/2042/16838
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