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The current hypothesis on the mechanism of dry and boundary friction conceives solid surfaces in contact as forming very minute welds or adhesions on the isolated areas of true contact. When sliding occurs, these welds are broken and new ones are formed. Other phenomena may also take place during sliding, but the present paper deals only with observations of the adhesion factor.

In the last few years bearing research has begun to open a new field of information on the effects of solids in the oil to sleeve bearings. Actually, we are just beginning to evaluate some of the design conditions that have existed for years. It is, therefore, no longer sufficient merely to state that a given solid is good or bad for bearing lubrication—we also must know how good or how bad the effects of the solid will be on a certain bearing material. A series of tests on babbitt bearings was reported in June, 1952. Continued research on copper‐lead and aluminium operating with particles of molybdenum sulphide, rouge, and corundum has shown some very significant effects on the bearing's friction and load‐carrying capacity. The authors are respectively Associate Professor, Dept.Mech.Eng., and Research Engineer, Defence Research laboratory, University of Texas, and this paper was presented at a Joint Session of the Machine Design Division and Lubrication Activity at the September, 1954, Meeting of the American Society of Mechanical Engineers.

When machine elements are examined after a period of use it is seldom possible to relate the damage observed with the simple theories of adhesive or abrasive wear. Examples taken from practice are described and explanations offered based on metallurgical and other changes in the affected surface region. It is concluded that further progress in understanding actual wear situations can only come from a multi‐disciplinary approach.

An enormous increase in air cargo in the near future has been predicted by various authorities and many surveys have been made to analyze the markets which should develop. But, so far as the authors are aware, little has been said about the actual engineering and mechanical problems involved in the handling of air cargo. It is true that several cargo aero‐plane designs have been evolved and proposed which include many novel construction features, but little has been available to designers in the way of specific operation and cargo handling recommendations.

BEARINGS AND LUBRICATION are extremely important in spacecraft mechanisms. As in any mechanism, good bearing and lubrication practices lead to high efficiency and low wear. The bearing and lubrication problem in space is somewhat severe because of weight limitations, reliability requirements, and the space environment. However, the problem may be satisfactorily solved in most cases by proper application of basic bearing theory and use of the proper materials and lubricants.

Available literature dealing with vibration is generally confined to ambitious volumes and text which presuppose a certain basic knowledge of the subject and which must often baffle the student reader.

Federal and state governments collaborate on state Medicaid nursing facility long-term care (SMNF-LTC) programs. These programs are increasingly expensive as the baby-boomers retire. Yet serious resident outcome problems continue in spite of the Centers for Medicare and Medicaid Services’ (CMS) extensive process-focused regulatory efforts. This study identifies a promising and simpler auxiliary path for improving resident outcomes.

Drawing on a longitudinal (1997–2005), 48-state data set and panel-corrected, time-series regression, we compare the effects on resident outcomes of CMS process-focused surveys and four minimally regulated program structural features on which the states vary considerably.

We find that each of these four structural features exerts a greater effect on resident outcomes than process quality.

We suggest augmenting current process-focused regulation with a less arduous approach of more extensive regulation of these program features.

To date SMNF-LTC program regulation has focused largely on member facility processes. While regulating processes is appropriate, we show that regulating program structural features directly, an arguably easier task, might well produce considerable improvement in the quality of resident outcomes.

Medicaid home and community-based services (HCBS) support community living for three million disabled people in the United States. As a state-federal partnership, these programs are highly variable across states. Because eligibility determination and services differ from state to state, this Medicaid structure becomes a barrier for those HCBS users whose desired futures include cross-state moves.

I examine narratives of citizenship and personhood for Medicaid HCBS users circulating within policy arenas and explore tensions between these and the stories Medicaid HCBS users tell of their own lives. Specifically, I explore the degree to which narratives about Medicaid HCBS users include an affirmation of the right to cross-state movement. My analysis includes data from public statements from policy makers, legislative texts, organizational framings of Medicaid policy, and 18 semi-structured interviews with Medicaid PCA users who desired or pursued cross-state moves.

I conclude that institutional narratives of Medicaid HCBS users are an inadequate representation of the stories told by those who rely on this program and, in consequence, programs stemming from policy fail to offer services that would allow service recipients to pursue their objectives.

Medicaid HCBS policy is part of a broader story of disability rights progress over the last four decades, making its role as an obstacle to cross-state movement a bit of a paradox. This paradox points to the value of narrative analysis in calling attention to invisible contradictions and the need for institutional and organizational change.

This paper aims to develop efficient decision support tools for a firm’s environment protection by using greening effort while yet improving profitability by utilizing pricing and inventory decisions with discount consideration.

This study proposed a mathematical model for price- and greening effort-dependent demand rate with discount considerations. Later, the mathematical model is extended to the situation in which the demand rate is also dependent on the stock level, in addition to the price and greening effort. Efficient solution methodologies are developed for finding the optimal solution to the proposed models.

Simple yet elegant models are proposed to mimic real-life applications. Structural properties of the models are explored to outline efficient algorithms with quantity discounts.

The paper considers monopoly and assumes deterministic demand. Only a more commonly observed all-units discount scheme is studied.

The models provide decision support tools for firms in pursuit of joint profit maximization and environment consciousness goals.

The study develops environment-friendly approaches for inventory management and improving the profitability alike.

This study is among the first to consider environmental protection with an investment in greening effort along with inventory management and pricing decision. The study also explored the effect of all-unit quantity discounts.

Whatever views may be held with regard to the question of the total prohibition or otherwise of chemical preservatives in foods, there can be little doubt that the broad theory underlying the recommendations of the Departmental Committee is perfectly, sound and consonant with the best interests of the public and the honest manufacturer. The use of chemical preservatives of any kind is undesirable, and if permitted at all, such preservatives should be restricted to substances which are not foreign to the human body. Referring to the various articles and letters which have recently appeared in The Times, Professor F. Gowland Hopkins, D.Sc., F.R.S., F.I.C., observes:—