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Article
Publication date: 21 November 2016

Sam Bieler

The purpose of this paper is to review the state of research of police militarization in the USA to explore the claim that the police are becoming more like the military, or…

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Abstract

Purpose

The purpose of this paper is to review the state of research of police militarization in the USA to explore the claim that the police are becoming more like the military, or “militarized” in order to identify gaps in the research on this topic that require further investigation.

Design/methodology/approach

To explore the state of police militarization, this paper draws on a scan of scholarly papers published on militarization in the American context as well as a select array of gray literature on the topic.

Findings

While the nature of militarization has received substantial scholarly attention, debate on the phenomenon remains and there is little consensus on the definition of what makes a department militarized. The impact of militarization is similarly unclear: some scholars suggest that it has a negative impact on policing because it creates community hostility and encourages police to see force as a central problem-solving tool. However, other scholars suggest militarization is a positive development, as it could promote professionalism and accountability. To date, there has been little empirical work on the impact of militarization on policing that could inform this debate.

Originality/value

This paper suggests that empirical assessments of how militarization affects use of force and legitimacy will be valuable for informing the militarization debate. As scholars on both sides of the debate have suggested that militarization affect policing outcomes in these areas, empirical tests here offer a way to explore both sides’ claims. Such tests could offer new evidence on how militarization is affecting the character and operations of American police.

Details

Policing: An International Journal of Police Strategies & Management, vol. 39 no. 4
Type: Research Article
ISSN: 1363-951X

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Article
Publication date: 12 April 2011

O. Nousiainen, O. Salmela, J. Putaala and T. Kangasvieri

The purpose of this paper is to describe the effect of indium alloying on the thermal fatigue endurance of Sn3.8Ag0.7Cu solder in low‐temperature co‐fired ceramic (LTCC) modules…

279

Abstract

Purpose

The purpose of this paper is to describe the effect of indium alloying on the thermal fatigue endurance of Sn3.8Ag0.7Cu solder in low‐temperature co‐fired ceramic (LTCC) modules with land grid array (LGA) joints and the feasibility of using a recalibrated Engelmaier model to predict the lifetime of LGA joints as determined with a test assembly.

Design/methodology/approach

Test assemblies were fabricated and exposed to a temperature cycling test over a temperature range of −40‐125°C. Organic printed wiring board (PWB) material with a low coefficient of thermal expansion was used to reduce the global thermal mismatch of the assembly. The characteristic lifetime, θ, of the test assemblies was determined using direct current resistance measurements. The metallurgy and failure mechanisms of the interconnections were verified using scanning acoustic microscopy, an optical microscope with polarized light, and scanning electron microscopy/energy dispersive spectrometry (SEM/EDS) investigations. Lifetime predictions of the test assemblies were calculated using the recalibrated Engelmaier model.

Findings

This work showed that indium alloying increased the characteristic lifetime of LGA joints by 15 percent compared with Sn3.8Ag0.7Cu joints. SEM/EDS analysis showed that alloying changed the composition, size, and distribution of intermetallic compounds within the solder matrix. It was also observed that a solid‐state phase transformation (Cu,Ni)6Sn5(→ (Ni,Cu)3Sn4 occurred at the Ni/(Cu,Ni)6Sn5 interface. Moreover, the results pointed out that individual recalibration curves for ceramic package/PWB assemblies with high (≥ 10 ppm/°C) and low (≈ 3‐4 ppm/°C) global thermal mismatches and different package thicknesses should be determined before the lifetime of LGA‐type assemblies can be predicted accurately using the recalibrated Engelmaier model.

Originality/value

The results proved that indium alloying of LGA joints can be done using In‐containing solder on pre‐tinned pads of an LTCC module, despite the different liquidus temperatures of the In‐containing and Sn3.8Ag0.7Cu solders. The characteristic metallurgical features and enhanced thermal fatigue endurance of the In‐alloyed SnAgCu joints were also determined. Finally, this work demonstrated the problems that exist in predicting the lifetime of ceramic packages with LGA joints using analytical modeling, and proposals for developing the recalibrated Engelmaier model to achieve more accurate results with different ceramic packages/PWB assemblies are given.

Details

Soldering & Surface Mount Technology, vol. 23 no. 2
Type: Research Article
ISSN: 0954-0911

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