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Article
Publication date: 3 May 2011

Fangwei Xie and Youfu Hou

The purpose of this paper is to reveal the characteristics of hydrodynamic load capacity and torque transferred by oil film with variable viscosity, and the effect of…

Abstract

Purpose

The purpose of this paper is to reveal the characteristics of hydrodynamic load capacity and torque transferred by oil film with variable viscosity, and the effect of groove number, width and depth on the hydrodynamic load capacity and torque transfer.

Design/methodology/approach

The radial temperature of friction pair and viscosity of YLA‐N32 hydraulic oil were measured through experiments, and a viscosity‐diameter expression was deduced using polynomial fitting method. Analytical expressions for hydrodynamic load capacity and torque of the oil film were deduced based on hydrodynamic lubrication theory.

Findings

The investigation shows the hydrodynamic load capacity and transferred torque with variable viscosity are much less than that with constant viscosity. Load capacity increases with the increase of groove depth which is the most significant influence factor, while it has the least influence on torque. Groove width has great influence on load capacity and torque. The load capacity increases with the increase of groove width; contrarily, torque decreases with the increase of groove width. Groove number has little influence on load capacity, while it has great influence on torque. The torque decreases with the increase of groove number.

Originality/value

In this paper, analytical solutions for hydrodynamic load capacity and torque of the oil film with variable viscosity are deduced. The paper reveals the relationship between hydrodynamic load capacity, torque transfer and groove number, width and depth.

Details

Industrial Lubrication and Tribology, vol. 63 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 1 April 1973

Current issues of Publishers' Weekly are reporting serious shortages of paper, binders board, cloth, and other essential book manufacturing materials. Let us assure you…

Abstract

Current issues of Publishers' Weekly are reporting serious shortages of paper, binders board, cloth, and other essential book manufacturing materials. Let us assure you these shortages are very real and quite severe.

Details

Reference Services Review, vol. 1 no. 4
Type: Research Article
ISSN: 0090-7324

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Article
Publication date: 12 July 2011

Habibeh Valizadeh Alvan and Husaini b. Omar

The matter of predicting disasters has always been one of the hottest and most challenging tasks in geology. Earthquakes are among the most destructive ones among all the…

Abstract

Purpose

The matter of predicting disasters has always been one of the hottest and most challenging tasks in geology. Earthquakes are among the most destructive ones among all the natural hazards. Occurring often without any warning, they are the most feared and unpredictable natural phenomena. In recent years with the emergence of new remote sensing instruments and techniques, geologists interested themselves to define accurate and reliable procedures to foresee disasters using this new technology. This paper aims to examine some of the data that have been used so far in earthquake prediction as well as cheap, relevant remotely sensing and geographic information systems methods to acquire and manipulate data.

Design/methodology/approach

Earthquakes are not the same in terms of origins, places (depth) and effects. So after having a brief look at the earthquakes, this paper examines the data that can be used for predicting earthquakes and reviews some of the remote sensing methods used to predict tectonic earthquakes. According to the types of measurements, remote sensing methods can be categorized in three main types; crust displacement, thermal and electromagnetic detecting techniques. Regarding the area's geological characteristics, satellites with optical and/or synthetic aperture radar sensors applications in prediction of large‐scale natural disasters will be discussed.

Findings

Presentation of the definitions and characteristics of earthquakes, categorized representation of the types of data used in this field as well as the types and names of the ground, aerial‐ and space‐borne data providers are the most important products of this review paper.

Originality/value

This method, if fully and systematically conducted, can be the cornerstone of an earth‐predicting system.

Details

Journal of Engineering, Design and Technology, vol. 9 no. 2
Type: Research Article
ISSN: 1726-0531

Keywords

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Book part
Publication date: 10 November 2014

Matthias Cinyabuguma, William Lord and Christelle Viauroux

This paper addresses revolutionary changes in the education, fertility and market work of U.S. families formed in the 1870s–1920s: Fertility fell from 5.3 to 2.6; the…

Abstract

This paper addresses revolutionary changes in the education, fertility and market work of U.S. families formed in the 1870s–1920s: Fertility fell from 5.3 to 2.6; the graduation rate of their children increased from 7% to 50%; and the fraction of adulthood wives devoted to market-oriented work increased from 7% to 23% (by one measure).

These trends are addressed within a unified framework to examine the ability of several proposed mechanisms to quantitatively replicate these changes. Based on careful calibration, the choices of successive generations of representative husband-and-wife households over the quantity and quality of their children, household production, and the extent of mother’s involvement in market-oriented production are simulated.

Rising wages, declining mortality, a declining gender wage gap, and increased efficiency and public provision of schooling cannot, individually or in combination, reduce fertility or increase stocks of human capital to levels seen in the data. The best fit of the model to the data also involves: (1) a decreased tendency among parents to view potential earnings of children as the property of parents and (2) rising consumption shares per dependent child.

Greater attention should be given the determinants of parental control of the work and earnings of children for this period.

One contribution is the gathering of information and strategies necessary to establish an initial baseline, and the time paths for parameters and targets for this period beset with data limitations. A second contribution is identifying the contributions of various mechanisms toward reaching those calibration targets.

Details

Factors Affecting Worker Well-being: The Impact of Change in the Labor Market
Type: Book
ISBN: 978-1-78441-150-3

Keywords

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Book part
Publication date: 24 October 2018

Charles R. McCann and Vibha Kapuria-Foreman

At the turn of the twentieth century, various Socialist parties vied for a place in the American political system, making alliances where possible and convenient with…

Abstract

At the turn of the twentieth century, various Socialist parties vied for a place in the American political system, making alliances where possible and convenient with elements of organized labor. Robert Franklin Hoxie, an economist at the University of Chicago whose principle contributions lay in his writings on the labor movement, wrote a series of essays in which he scrutinized the activities of the Socialist Party of America as it appeared to be at the time poised to become a viable force in American politics. This essay examines Hoxie’s writings on the conventions of the Socialist Party within the context of the political dynamic of the period and reveals his interpretations of events based on contemporary accounts and first-hand observations.

Details

Including a Symposium on Mary Morgan: Curiosity, Imagination, and Surprise
Type: Book
ISBN: 978-1-78756-423-7

Keywords

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Article
Publication date: 1 March 1964

S.R. RANGANATHAN

After establishing the terminology, shows how the choice of the name of the subject of a document and the rendering of the name in the heading of the specific subject…

Abstract

After establishing the terminology, shows how the choice of the name of the subject of a document and the rendering of the name in the heading of the specific subject entry can be got by facet analysis based on postulates and principles. After showing that subject headings constitute an artificial language, points out that using facet analysis for subject heading does not amount to using class number. Marks out the area for an objective statistical survey of sought heading for subject entry. Calls on Council for Library Resources Incorporated to provide for this project.

Details

Journal of Documentation, vol. 20 no. 3
Type: Research Article
ISSN: 0022-0418

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Article
Publication date: 14 August 2009

Zhang Longhua

The purpose of this paper is to develop novel ashless additives and to meet the need for formulating ashless anti‐wear (AW) hydraulic fluid or other industrial lubricating…

Abstract

Purpose

The purpose of this paper is to develop novel ashless additives and to meet the need for formulating ashless anti‐wear (AW) hydraulic fluid or other industrial lubricating oils. This paper also aims to investigate the tribological behaviours and mechanism of an acrylate of dialkyl dithiophosphoric acid (ADDP), as an additive in some group I/II base oils compared with some traditional s‐p containing AW additives.

Design/methodology/approach

ADDP is synthesized in the laboratory. The chemical composition and structure of the lubricating additive are analyzed by means of infrared spectroscopy. Its extreme pressure (EP), AW and friction reduction properties as additive in base oils, compared with some traditional s‐p containing AW additives, are investigated using a four‐ball machine according to relative testing standards. The tribological mechanism is discussed according to the scanning electron microscope (SEM) analytical data.

Findings

The results indicate that the four‐ball PB value of the prepared ADDP in HVIWH650 is better than that of the IRGLUBE 353; the thermal stability of ADDP is equivalent to the zinc dialkyl dithiophosphate (ZDDP) and the SEM data show that the prepared ADDP additive could form a layer of uniform film on the worn surface serving as lubricant and protective film. This may be the chief reason why the prepared ADDP possesses better AW property than ZDDP.

Research limitations/implications

However, more experimental studies such as the synergic effect with other additives should be performed, from which it could be learned whether the novel AW additive would be applicable in industrial oils.

Practical implications

The results may be useful for the researchers to formulate some ashless industrial oils.

Originality/value

A novel additive was synthesized in the laboratory; it would find a promising industrial application as an ashless AW additive.

Details

Industrial Lubrication and Tribology, vol. 61 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 22 June 2010

Xianguo Hu, Yourong Wang and Hefeng Jing

The purpose of this paper is to develop a new oil‐in‐water (O/W) emulsion used for alpha phase brass, which can increase the antiwear and anti‐galling abilities of the…

Abstract

Purpose

The purpose of this paper is to develop a new oil‐in‐water (O/W) emulsion used for alpha phase brass, which can increase the antiwear and anti‐galling abilities of the rollers, and improve the surface quality of the rolled brass sheet. The aim is to evaluate the tribological performance of new kind of O/W emulsion for the hot rolling of alpha brass, which provides the fundamental information for the selecting of new chemical group, and to understand the lubrication mechanism of the used rolling emulsion and to correlate the laboratory findings with those of industrial rolling of alpha phase brass.

Design/methodology/approach

According to the hydrophile‐lipophile balance theory and the evaluation results of friction, wear and lubrication using a four‐ball tribometer, a novel O/W emulsion was developed for the hot rolling process of CuZn32(ASTM C26200) and CuZn30(ASTM C26000) alloys by controlling the composition of the emulsion, such as emulsifying, antiwear, extreme pressure, antirust and so on. By scanning electron microscope (SEM), energy‐dispersive X‐ray (EDX), and roughness profile the tribological mechanism were studied.

Findings

The production result proved that it was easy to control the accuracy and size of the brass sheet because of the emulsion‐jet to the roller surface directly and in succession. Polyol with hydroxyl group is found to provide better lubrication and lower coefficient of friction. The actual hot rolling results proved that it was easy to control the accuracy and size of the brass sheet with the emulsion jet. The morphologies and roughness profile of the copper sheet surface were observed and measured by SEM and topographic meter under different lubricant conditions. The in situ results supported the selection of compositions of O/W emulsion. The suitable temperature of feed emulsion is over 20°C.

Research limitations/implications

The tribological mechanism of friction modified emulsion is not still clear. The thermal mechanical properties of rollers under this kind of emulsion are also worth studying in the future.

Practical implications

Understanding the tribological behaviour of O/W emulsion, will be useful for emulsion chemists, tribologists and rolling mill users.

Originality/value

The current study shows new compositions of O/W emulsion used for hot rolling of alpha phase brass.

Details

Industrial Lubrication and Tribology, vol. 62 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

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Book part
Publication date: 3 October 2015

Flora Farago, Kay Sanders and Larissa Gaias

This chapter draws on developmental intergroup theory, parental ethnic-racial socialization literature, anti-bias curricula, and prejudice intervention studies to address…

Abstract

This chapter draws on developmental intergroup theory, parental ethnic-racial socialization literature, anti-bias curricula, and prejudice intervention studies to address the appropriateness of discussing race and racism in early childhood settings. Existing literature about teacher discussions surrounding race and racism is reviewed, best practices are shared, and the need for more research in this area is highlighted. The construct of parental ethnic-racial socialization is mapped onto early childhood anti-bias classroom practices. The chapter also outlines racial ideologies of teachers, specifically anti-bias and colorblind attitudes, and discusses how these ideologies may manifest in classroom practices surrounding race and racism. Colorblind ideology is problematized and dissected to show that colorblind practices may harm children. Young children’s interpretations of race and racism, in light of children’s cognitive developmental level, are discussed. Additionally, findings from racial prejudice intervention studies are applied to teaching. Early literacy practices surrounding race and racism are outlined with practical suggestions for teachers and teacher educators. Moreover, implications of teacher practices surrounding race and racism for children’s development, professional development, and teacher education are discussed.

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Book part
Publication date: 10 April 2017

Antonio V. Menéndez Alarcón

This chapter examines the patterns of immigrants’ integration in a state of the Midwest of the United States, Indiana, which has experienced a growth of more than 250% of…

Abstract

This chapter examines the patterns of immigrants’ integration in a state of the Midwest of the United States, Indiana, which has experienced a growth of more than 250% of the foreign-born population in the last 20 years. The study, based on in-depth interviews and document analysis, examines the ways that immigrants blend into mainstream society in everyday life and in social interactions, as well as the obstacles they encounter in this process. The study reveals the cultural changes in the host culture as a result of the large number of immigrants who have established their residence in this state, the dichotomies that emerge between “natives” and “newcomers.” It also shows that immigrants stay connected to their country of origin through electronic media (in particular television and computers) and how this technology affects the process of integration. Finally, the study demonstrates that there is a process of segmented assimilation and variations in the immigrants’ sense of identity according to their socioeconomic status and ethnic background.

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