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The accounting literature has traditionally focused on firm-level studies to examine the capital market implications of earnings and other accounting variables. We first develop the arguments for studying capital market implications at the aggregate level as well. A central issue is that diversification makes equity investors at least partially and potentially almost completely immune to several firm-level properties of earnings by holding diversified portfolios. Diversification is particularly important when assessing the welfare consequences of random errors in accounting measurement (imperfect accruals) and, to the extent it is independent across firms, of deliberate manipulation (earnings management). Consequently, some firm-level metrics of association, timeliness, value relevance, conservatism and other earnings properties do not map easily into investor welfare. Similarly, earnings-related risk manifests itself to equity investors largely through systematic earnings risk (covariation with aggregate earnings and/or other macroeconomic indicators). We conclude that the design and evaluation of financial reporting must adopt at least in part an aggregate perspective. We then summarize the literature in accounting, economics and finance on aggregate earnings and stock prices. Our review highlights the importance of studying earnings at the aggregate level.

This study investigates the relationship between environmental concern, environmental effort and their impact on company performance. Results based on survey data from sixty companies indicate that there is a positive correlation between environmental concern and effort. In addition, positive correlations between effort and operations efficiency and company image were found. No significant correlation between environmental effort and profit was found. It was observed that top management concern is a key to environmental initiatives. Manufacturing companies seem to have higher concern than those of service companies and expend more effort in reducing pollution, waste recycling etc. However, there is no significant difference in impact on performance between manufacturing and service companies relative to environmental efforts.

A model of inter‐corporate power is derived from previous work on social power. The model consists of two portions – one dealing with influences on the amount of power companies have and one dealing with influences on the use of that power. This model is used to analyze competition. Suggestions are made about ways companies may increase their own power or influence the power relationships in their environment.

Currently over seventy percent of the work force is employed in white‐collar jobs. The implication ofwhite‐collar productivity for organizational growth and competitiveness is extremely significant. It is easy to measure the productivity for blue‐collar employees, as the inputs and outputs are well defined. However the process of measuring the productivity of the white‐collar employee is complicated. A model for measuring white‐collar productivity is presented. The organization should design its own productivity measures seeking active employee involvement. The measures developed should be used to design productivity improvement strategies for long term growth and competitiveness of the organization.

Reviews previous research based on event study methodology, pointing out that events can influence returns in many ways, and applies the method to a sample of mergers and acquisitions in the thinly traded Norwegian market 1983‐1994. Explains how the classic market model can be adjusted to control for non‐synchronous trading and changing/asymmetric volatility; and how the event and non‐event periods can be combined into a single model. Applies two different models to the data, compares the results and finds the ARMA‐GARCH approach superior to the OLS. Discusses the implications of this for researchers.

The purpose of this paper is to investigate the effects of two different weight percentages of lanthanum on tin–zinc–antimony solder alloys. Two manufacturing techniques were used: the furnace melting method (FMM) and ball milling method (BMM). The alloys were characterized and mechanically tested.

Tin–zinc–antimony alloys with 0.5 and 1% lanthanum were prepared by FMM and BMM for 25, 30 and 35 h. The tensile, shear, hardness, wear and corrosion properties were characterized using optical microscopy, scanning electron microscopy and X-ray diffraction.

Ball-milled samples were harder and more resistant to wear than furnace-melted samples. Corrosion tests showed that ball-milled samples of both the 0.5 and 1% lanthanum tin-based solders showed higher corrosion than furnace-melted samples. The ball-milled samples exhibited a uniform particle distribution. The ductility of the milled samples was significantly higher than that of the furnace-melted ones. There was strong evidence of the presence of nanoparticles. X-ray diffraction revealed some amorphous phases, which have not been previously reported.

The quality of solder alloys prepared by FMM and BMM was compared. This comparison was not made in previous studies. In addition to the hardness, the wear and corrosion resistances were measured, which have not been previously reported. There seems to be evidence of the presence of nanoparticles in the solder, as suggested by the increase in the elongation. Tensile, elongation and shear tests were performed, and a theory was provided for the results obtained.

This paper aims to investigate the temperature and wear properties of vertical ball screws and to discuss the surface design of ball screws in industrial applications.

The energy equation of the screw surface considering the frictional heat was established to verify the surface temperature of the ball screw. X-ray diffraction was used to examine the micro-contact temperature between the ball and screw. Debris size and density were examined to investigate wear properties of ball screws and to study the relationship of wear debris and temperature.

First, the main energy source for the surface temperature of high speed vertical ball screws is derived from friction force between ball and screw. Second, the temperature rise between the ball and screw has great relevance with wear debris concentration. Third, the surface temperature of the screw is higher than between the nut and ball for high speed vertical ball screws due to high convection heat transfer. The contact temperature of the nut near the flange is smaller than that of the nut away from the flange end due to the high contact load and thermal conduction. Finally, correlation of particle size and surface roughness value for vertical ball screws was established, and its effects on contact temperature were studied. The theoretical analysis and experiments will help to characterize the design and manufacture of vertical ball screws.

The surface temperature and micro-contact temperature analytical model were established to study the ball screw design. Based on the surface-particle micro-contact temperature balance, the optimal range of surface roughness was designed for vertical ball screws, considering the wear debris and micro-contact temperature.

In order to meet the requests of exploring environmental-friendly and multifunctional lubricant additives, some novel dimercaptothiadiazole derivatives containing hydroxyl are prepared and used as antiwear (AW) and extreme-pressure (EP) additives in biodegradable lithium grease. The paper aims to discuss these issues.

The tribological performances of the grease samples containing these derivatives are evaluated by using a four-ball tester. X-ray absorption near edge structure (XANES) spectroscopy is used to analyze the chemistry of tribofilms under AW/EP regime, and thermal films are also considered for comparison.

The tribological tests show that these derivatives are all effective in reducing wear, especially at lower additive concentrations, but they are basically failed in reducing friction. They are also helpful in improving the EP characteristic of the base grease. The thermal films generated by these derivatives are composed of adsorbed organic sulfide and ferrous sulfate, though for short-chain derivatives, organic sulfide is the only component at 5.0 wt.%. Ferrous sulfide is the main component of the tribofilms formed by these derivatives at various additive concentrations. But for short-chain derivatives, these tribofilms consist of ferrous sulfide and ferrous disulfide at 5.0 wt.%, and the appearance of disulfide suggests that the interfacial temperature between the upper ball and three lower balls under these conditions is considerably low. The EP films generated by short-chain derivatives are all composed of organic sulfide and ferrous sulfide, while for long-chain derivatives, ferrous sulfide is the main component.

These low-toxic and oil-soluble dimercaptothiadiazole derivatives are effective in improving the tribological characteristic of the biodegradable lithium grease, and these heterocyclic derivatives may be good substitutes for some harmful traditional additives.

Historically, tin‐lead solder has been a commonly used joining material in electronics manufacturing. Environmental and health concerns, due to the leaching of lead from landfills into ground water, have necessitated legislation that restricts the use of lead in electronics. The transition from tin‐lead solder to a lead‐free solder composition is imminent. Several alternative solder alloys (and their fluxes) have been researched for electronics assembly in the last few years. The objective of this research was to develop a systematic selection process for choosing a “preferred” lead‐free solder paste, based on its print and reflow performance.

After a detailed study of industry preferences, published experimental data, and recommendations of various industrial consortia, a near eutectic tin‐silver‐copper (SAC) composition was selected as the preferred alloy for evaluation. Commercially available SAC solder pastes with a no‐clean chemistry were extensively investigated in a simulated manufacturing environment. A total of nine SAC pastes from seven manufacturers were evaluated in this investigation. A eutectic Sn/Pb solder paste was used as a baseline for comparison. While selecting the best lead‐free paste, it was noted that the selected paste has to perform as good as, if not better than, the current tin‐lead paste configuration used in electronics manufacturing for a particular application. The quality of the solder pastes was characterized by a series of analytical and assembly process tests consisting of, but not limited to, a printability test, a solder ball test, a slump test, and post reflow characteristics such as the tendency to form voids, self‐centring and wetting ability.

Each paste was evaluated for desirable and undesirable properties. The pastes were then scored relative to each other in each individual test. An aggregate of individual test scores determined the best paste.

This paper summarizes a systematic approach adopted to evaluate lead‐free solder pastes for extreme reflow profiles expected to be observed in reflow soldering lead‐free boards.

This paper sets out to study tribological properties, anticorrosive performances and thermal stabilities of two novel S‐N type triazinyl‐containing polysulfides {Bis[2,4‐bis(diethylamino)‐s‐triazin‐6‐yl] polysulfide (BBET‐PS) and Bis[2,4‐bis(di‐n‐butylamino)‐s‐triazin‐6‐yl] polysulfide (BBBT‐PS)} as additives in biodegradable grease, and to estimate the tribochemical mechanism.

Extreme pressure (EP) and anti‐wear (AW) properties of two compounds at different addition concentration were evaluated using a four‐ball machine. Their wear scar was analyzed with X‐ray photoelectron spectroscopy (XPS) and a scanning electron microscope.

Two novel S‐N type triazinyl‐containing polysulfides possess excellent load‐carrying capacity, good AW and show good corrosion‐inhibiting performance. The thermal stability of BBB‐PS is better than that of BBE‐PS. According to the XPS results, the triazinyl‐containing polysulfides react with the metal to generate a surface protective film consisting of sulfate, FeS and absorbed compounds containing organic‐N.

The antioxidant and biodegradability of the two novel compounds were not investigated.

Two effective EP and AW additives were synthesized, and maybe potentially industrial applied lubricating grease additives.

The achievement of this study is the synthesis of two triazinyl‐containing polysulfides, which can be effective additives to improve the tribological performance of biodegradable grease.