Search results

This issue is a selected bibliography covering the subject of leadership.

The Minister of Technology, Mr Anthony Wedgwood Benn, in agreement with the Secretary of State for Defence, has appointed Captain W. E. Morris, R.N., as Director, Royal Naval Aircraft and Helicopter Development.

Compression rings are the main sources of frictional losses in internal combustion engines. The present paper aims to present a thermo-mixed hydrodynamic analysis for coated top compression rings. To understand the coating effects, the main tribological parameters are investigated into a ring-cylinder conjunction in a motorbike engine. Furthermore, flow simulations have been carried out on how different worn profiles on the cylinder inner liner affects friction, lubricant film and localized contact deformation of the coated compression rings.

In this paper, the basic geometrical dimensions of the top compression ring-cylinder system are obtained from a real motorbike engine. A 2D axisymmetric CFD/FLOTRAN model is created for coated compression rings. Flow simulations are performed by solving the Navier-Stokes and the energy equations. The load capacity of the asperities is also taken into account by Greenwood and Tripp contact model. Realistic boundary conditions are imposed to simulate the in-plane ring motion. The simulation model is validated with analytical and experimental data from the literature. Under thermal considerations, the contribution of worn cylinder profiles in conjunction with different coated compression rings is presented.

This research shows that because of thermal effects, the boundary friction is higher at reversals and the viscous friction is lower because of reduced oil viscosity. As regards to the isothermal case, the viscous friction is greater because of a higher lubricant viscosity. In the case of chromium-plated ring, boundary friction was 16 per cent lower than a grey cast iron ring taking into account thermal effects. Regarding the localized contact deformation, the coated compression rings showed lower values under different worn cylinder shapes. In particular, hard wear-resistant (Ni-Cr-Mo) coating showed the slighter local deformation. Therefore, the worn cylinder profiles promote boundary/mixed lubrication regime, whereas the lobed profile of cylinder inner liner becomes more wavy.

The solution of the thermo-mixed lubrication model, concerning the piston ring and worn cylinder tribo pair by taking into account the coating of the top compression ring.

The purpose of this paper is to study the real-time change of surface roughness at different small regions of piston rings during running-in process. Meanwhile, the effects of real-time change of the rough surface topography on the lubrication and friction of piston rings are investigated.

An uneven wear model has been developed to research the running-in behavior at the different small regions of piston rings. The model is verified by comparing the simulation results with the experimental results on a reciprocating friction and wear test rig.

This research shows that the wear process of piston ring surface is uneven during running-in. At most time of the operating cycle except the vicinity of top dead center and bottom dead center, the minimum oil film thickness ratio increases while the friction force and power loss decrease after the running-in period.

Through this research, the running-in behavior of piston rings is investigated in detail. The interaction between the running-in and the lubrication and friction of piston rings is understood more deeply.

The cardinal point to note here is that the development (and unfortunately the likely potential) of area policy is intimately related to the actual character of British social policy. Whilst area policy has been strongly influenced by Pigou's welfare economics, by the rise of scientific management in the delivery of social services (cf Jaques 1976; Whittington and Bellamy 1979), by the accompanying development of operational analyses and by the creation of social economics (see Pigou 1938; Sandford 1977), social policy continues to be enmeshed with the flavours of Benthamite utilitatianism and Social Darwinism (see, above all, the Beveridge Report 1942; Booth 1889; Rowntree 1922, 1946; Webb 1926). Consequently, for their entire history area policies have been coloured by the principles of a national minimum for the many and giving poorer areas a hand up, rather than a hand out. The preceived need to save money (C.S.E. State Apparatus and Expenditure Group 1979; Klein 1974) and the (supposed) ennobling effects of self help have been the twin marching orders for area policy for decades. Private industry is inadvertently called upon to plug the resulting gaps in public provision. The conjunction of a reluctant state and a meandering private sector has fashioned the decaying urban areas of today. Whilst a large degree of party politics and commitment has characterised the general debate over the removal of poverty (Holman 1973; MacGregor 1981), this has for the most part bypassed the ‘marginal’ poorer areas (cf Green forthcoming). Their inhabitants are not usually numerically significant enough to sway general, party policies (cf Boulding 1967) and the problems of most notably the inner cities has been underplayed.

This study examined the relationships of normative and affective facets of organizational commitment with experienced burnout within the framework of the Confucian‐based Chinese culture. Data for this exploratory work were collected through a questionnaire survey of 147 employees of a Chinese‐owned bank in Hong Kong. The questionnaire consisted of scales on experienced burnout, organizational commitment, and work perceptions. Results showed that the mean score for normative commitment was significantly higher than the mean score for affective commitment. Regression analysis indicated that when age, tenure, organizational level, and work perceptions were controlled, normative commitment had a significant positive effect on experienced burnout, whereas affective commitment had no significant impact. Results are interpreted in the context of a Confucian‐based Chinese managerial ideology and implications are drawn for future research.

The factors governing the flow properties of grease are discussed with particular reference to the RN multipurpose grease XG‐274 and the soft lime‐base grease LG‐380. Results obtained at 70°F using a pumping rig with pipes of ½ inch, ¾ inch or ¼ inch external diameter are presented in terms of apparent viscosity in line with the procedure approved by the National Lubricating Grease Institute. The data can be used to assess the suitability of systems proposed for dispensing the greases, supplemented where necessary by apparent viscosity measurement by Standard Method ASTM‐D 1092.

Entrepreneurship ecosystems have become ubiquitous in the discussions around economic growth and new venture creation. Despite growing scholarly interest, however, the theoretical and conceptual foundations are still rudimentary, causing much debate among researchers and practitioners. At the center of these debates are questions like What are the boundaries of ecosystems? Are ecosystems build from the top-down or from the bottom-up? Or How can we measure the success of ecosystems? In this chapter, we summarize these discussions, present an overview of the existing research, and give an outlook on future directions.

Aging and mental illness both represent significant public health challenges for incarcerated people in the USA. The COVID-19 pandemic has further highlighted the vulnerabilities of incarcerated people because of the risks of infectious disease transmission in correctional facilities. Focusing on older adults with mental illness, this paper aims to examine efforts to decarcerate US correctional facilities during the COVID-19 pandemic and whether these approaches may lead to sustainable reforms beyond the pandemic.

A narrative literature review was conducted using numerous online resources, including PubMed, Google Scholar and LexisNexis. Search terms used included “decarceration pandemic,” “COVID-19 decarceration,” “aging mental illness decarceration,” “jails prisons decarceration,” “early release COVID-19” and “correctional decarceration pandemic,” among others. Given the rapidly changing nature of the COVID-19 pandemic, this narrative literature review included content from not only scholarly articles and federal and state government publications but also relevant media articles and policy-related reports. The authors reviewed these sources collaboratively to synthesize a review of existing evidence and opinions on these topics and generate conclusions and policy recommendations moving forward.

To mitigate the risks of COVID-19, policymakers have pursued various decarceration strategies across the USA. Some efforts have focused on reducing inflow into correctional systems, including advising police to reduce numbers of arrests and limiting use of pretrial detention. Other policies have sought to increase outflow from correctional systems, such as facilitating early release of people convicted of nonviolent offenses or those nearing the end of their sentences. Given the well-known risks of COVID-19 among older individuals, age was commonly cited as a reason for diverting or expediting release of people from incarceration. In contrast, despite their vulnerability to complications from COVID-19, people with serious mental illness (SMI), particularly those with acute treatment needs, may have been less likely in some instances to be diverted or released early from incarceration.

Although much has been written about decarceration during the COVID-19 pandemic, little attention has been paid to the relevance of these efforts for older adults with mental illness. This paper synthesizes existing proposals and evidence while drawing attention to the public health implications of aging and SMI in US correctional settings and explores opportunities for decarceration of older adults with SMI beyond the COVID-19 pandemic.