FINANCIAL fears are only less cruel than those of war, and lead men into extravagances which they would repudiate indignantly in their cooler moments. If the doings of the Economy…
Abstract
FINANCIAL fears are only less cruel than those of war, and lead men into extravagances which they would repudiate indignantly in their cooler moments. If the doings of the Economy Committee at Manchester in relation to children's libraries, as described in the article by Mr. Lamb in our last issue, are true, we have in them an example of a kind of retrenchment at the expense of the young which we hope is without parallel and will have no imitators. Some reduc‐tion of estimates we hear of from this or that place, but in few has the stupid policy which urges that if we spend nothing we shall all become rich been carried into full effect. Libraries always have suffered in times of crisis, whatever they are; we accept that, though doubtfully; but we do know that the people need libraries.
W.J. Ready, S.R. Stock, G.B. Freeman, L.L. and L.J. Turbini
Under certain environmental conditions, printed wiring boards (PWBs) respond to applied voltages by developing sub‐surface deposits of copper salts extending from anode to cathode…
Abstract
Under certain environmental conditions, printed wiring boards (PWBs) respond to applied voltages by developing sub‐surface deposits of copper salts extending from anode to cathode along separated fibre/epoxy interfaces. These deposits are termed conductive anodic filaments (CAFs) and, in this work, the dimensions and growth patterns of a CAF have been determined by serial sectioning. The CAF growth pathway is characterised and the spatial distribution of the copper salts is quantified with scanning electron microscopy (SEM) using backscattered electrons. The chemical composition of the CAF is determined using energy dispersive X‐ray analysis (EDS). Prior research using high‐resolution non‐destructive X‐ray microtomography is correlated with the serial sectioning data. The failure phenomenon known as CAF may pose serious long‐term reliability concerns in electronics applications exposed to adverse and hostile environments.
Dae-Young Kim, Scott W. Phillips and Stephen A. Bishopp
The present study examines a range of police force on the continuum (firearms, TASER/chemical spray and physical force) to see whether they are associated with individual (subject…
Abstract
Purpose
The present study examines a range of police force on the continuum (firearms, TASER/chemical spray and physical force) to see whether they are associated with individual (subject and officer), situational and/or neighborhood factors.
Design/methodology/approach
A partial proportional odds model is used to analyze police use of force data from 2003 to 2016 in Dallas. Independent variables are allowed for varying effects across the different cumulative dichotomizations of the dependent variable (firearms vs TASER/chemical spray and physical force and firearms and TASER/chemical spray vs physical force).
Findings
Most officer demographic and situational factors are consistently significant across the cumulative dichotomizations of police force. In addition, suspect race/ethnicity (Hispanic) and violent crime rates play significant roles when officers make decisions to use firearms, as opposed to TASER/chemical spray and physical force. Overall, situational variables (subject gun possession and contact types) play greater roles than other variables in affecting police use of force.
Originality/value
Despite the large body of police use of force research, little to no research has used the partial proportional odds model to examine the ordinal nature of police force from physical to intermediate to deadly force. The current findings can provide important implications for policy and research.
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Keywords
Conductive anodic filament (CAF) is a failure mode in printed wiring boards (PWBS), which occurs under high humility and high voltage gradient conditions. This paper aims to…
Abstract
Purpose
Conductive anodic filament (CAF) is a failure mode in printed wiring boards (PWBS), which occurs under high humility and high voltage gradient conditions. This paper aims to review the history of CAF from its identification in the 1970s to the statistical analysis of its failure mode and the factors that enhance its formation.
Design/methodology/approach
Charts the chronology and details the developments of CAF over the last 30 years.
Findings
CAF is a conductive copper‐containing salt created electrochemically that grows from the anode toward the cathode sub‐surface along the epoxy/glass interface. It can also grow from the anode on one layer to a cathode on another. CAF was first discovered in 1976 and was identified as a catastrophic failure mode. It is enhanced by high humidity during storage or use, by high voltage gradient between anode and cathode, by certain soldering flux ingredients, by hole drilling, multiple thermal cycles during processing, and by higher processing temperatures associated with lead‐free solders. CAF is a copper hydroxy chloride salt and is a semiconducting material.
Originality/value
Our analytical tools today are far superior to those of these early researchers. Early data were obtained from chart recorders and manual plotting. Today we have computers for automated data collection and analysis and the sensitivity of the scanning electron microscope has improved significantly. The researchers of the 1970s and early 1980s characterized the basic factors associated with CAF and in many ways we are just repeating what they have done.
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Keywords
Marcio Pereira Basilio and Valdecy Pereira
Because that the crime in a wide way impacts the life of the people in the big metropolis, researchers have treated the question from several angles. The purpose of the paper…
Abstract
Purpose
Because that the crime in a wide way impacts the life of the people in the big metropolis, researchers have treated the question from several angles. The purpose of the paper, under the umbrella of operational research, is to develop a model of the ordering of police strategies, in the fight against crime in general, according to a certain criminal demand.
Design/methodology/approach
For the construction of the impact matrix of the strategies under the reduction of crime rates, considering a portfolio of crimes, a questionnaire applied to specialists was used. In a second moment, defined the criteria and strategies to be ordered, the multicriteria ELECTRE IV method was used, which with the help of the J-Electre software emulated the systematized data in the impact matrix and produced the final ordering of the most efficient strategies, in the fight against crime, in the perception of decision-makers.
Findings
As a result, the research revealed that policing strategies directed at solving specific crimes are the most effective in the perception of decision-makers after the emulation of data with the ELECTRE IV method.
Research limitations/implications
As research implications, it can be inferred that the use of multicriteria methods in the modeling of problems in the area of public security can contribute to rationalization of the use of the means available in the fight against crime in large cities. The research showed that it is possible to use customized policing strategies to a certain reality.
Practical implications
The method presented in this research is directly related to the major strategies: problem-oriented policing and hot spot policing. This method allows public safety managers to consider the possibility of combining different law enforcement strategies in each context. In this sense, the use of the multiple-criteria decision analysis (MCDA) (ELECTRE IV) method allows the evaluation of a large set of alternatives according to a set of established criteria, speeding up the process and reducing subjectivity, allowing the manager to analyze several scenarios with greater clarity and impartiality and choosing an alternative that best solves the proposed problem. The expected result is the rationalization of the available means applied in the search for the reduction of crime rates.
Social implications
The customization of policing strategies, according to criminal demands, implies the efficient way to reduce criminal charges. Reducing criminal rates enables the development of the local economy, tourism and the quality of life of people by exercising their freedom to the full.
Originality/value
The originality lies in filling a gap in the literature with the elaboration of the impact matrix of policing strategies in reducing criminal indices, and in their associated use in ordering strategies through a multicriteria method.
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Keywords
The 1980s and 1990s have seen the development of new andinteresting soldering flux formulations. Many of these fluxes exhibit improved solderingperformance or are favoured because…
Abstract
The 1980s and 1990s have seen the development of new and interesting soldering flux formulations. Many of these fluxes exhibit improved soldering performance or are favoured because of their reduced environmental impact. In order to further the understanding of these new fluxes and their interaction with the metallisation on the printed wiring board, as well as the substrate itself, one needs to examine test methods carefully and begin to correlate the data among the existing test methods. At Georgia Tech a variety of data have been collected on a number of fluxes including water soluble, low solids and activated rosin fluxes. Test methods for flux characterisation include surface insulation resistance testing, corrosion test measurements and recently impedance spectroscopy at low frequencies. This paper will review the variety of fluxes available, report on results of testing these fluxes using the techniques mentioned above and will define the important information related to soldering flux interactions which each test method uncovers.
Details
Keywords
Justin Ready, Michael D. White and Christopher Fisher
This paper sets out to encompass a comparative analysis of news reports and official police records of TASER deployments from 2002 to 2005.
Abstract
Purpose
This paper sets out to encompass a comparative analysis of news reports and official police records of TASER deployments from 2002 to 2005.
Design/methodology/approach
The methodology involves a content analysis of all LexisNexis and New York Times articles involving police use of the TASER during the study period (n = 353). Regional (New York Times) and national (LexisNexis) news reports describing police use of the TASER are compared with police reports of all TASER deployments by the New York City Police Department (NYPD) during the same timeframe (n = 375).
Findings
Descriptive statistics and logistic regression are used to compare the data sources with respect to: the circumstances in which the weapon is deployed; the characteristics of the suspects involved in the TASER incidents; and the significant predictors of continued suspect resistance and repeated use of the TASER by an officer.
Research limitations/implications
The paper examines official police records on TASER deployments from one police agency. This limits the ability to generalize the research findings to other police agencies that have adopted different practices and policies regulating the deployment of CEDs. Additionally, the content analysis includes only articles in the mainstream print media.
Practical implications
The paper concludes with a discussion about some myths associated with news reports on police use of the TASER, and their potential impact on both public perception and police practices.
Originality/value
To date, research has not systematically compared media representations of the TASER with official reports on police deployments of the weapon. That is the focus of this paper.
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Per Johander, Per‐Erik Tegehall, Abelrahim Ahmed Osman, Göran Wetter and Dag Andersson
This paper aims to evaluate the influence of previous exposure to moisture on delamination and formation of CAF (conductive anodic filament) in printed circuit boards used for…
Abstract
Purpose
This paper aims to evaluate the influence of previous exposure to moisture on delamination and formation of CAF (conductive anodic filament) in printed circuit boards used for lead‐free soldering.
Design/methodology/approach
The moisture absorption and desorption characteristics of printed circuit boards were evaluated according to the IPC/JEDEC J‐STD‐020C standard for handling of moisture sensitive components. The CAF test was performed according to IPC‐TM‐650, Test Method 2.6.25.
Findings
Printed circuit boards used for lead‐free soldering must be treated as moisture sensitive components. Severe delamination occurred on test boards that had been exposed to JEDEC level 1 conditions prior to soldering, while no delamination was observed on boards exposed to level 3. Furthermore, previous moisture and thermal exposure had a strong influence on CAF formation. The insulation resistance dropped three decades in less than 15 h in the worst case.
Research limitations/implications
There are considerable stresses on printed circuit boards in lead‐free soldering processes. The influence from materials and processes is very large on the CAF formation. Therefore, a useful strategy is to evaluate the CAF properties for each supplier and material.
Originality/value
The paper pin‐points previous moisture exposure as a very important factor for delamination and CAF formation and confirms that printed circuit boards must be treated as moisture sensitive components.
Details
Keywords
Vantage Circuit Products, Bolton based suppliers of speciality chemicals and materials to the electronics industry, have agreed with Du Pont to supply soldering products, notably…
Abstract
Vantage Circuit Products, Bolton based suppliers of speciality chemicals and materials to the electronics industry, have agreed with Du Pont to supply soldering products, notably the ‘Solderel’ range and the ‘Sipad’ system into the UK market.
British automatic optical inspection (AOI) equipment manufacturer, Lloyd Doyle, has made several key appointments in its continued growth as a supplier of PCB inspection equipment.