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This study aims to compare the friction and wear performance of commercial brake pads for four wheelers among metallic, semimetallic and non-asbestos organic (NAO) formulations to identify one with the right combination of properties for optimal performance.

Three commercially available brake pads for four-wheeler automotive applications were acquired. Samples were cut from the brake pads to study their physical and mechanical properties. The effects of friction and wear were analyzed using a pin-on-disk tribotester. Surface morphology on the worn-out surface of the brake pads was studied.

It was observed that the frictional properties remained stable and less fluctuating in the semimetallic and NAO pads, whereas the coefficient of friction of all the pads varied between 0.35 and 0.55. The wear rate of the metallic pads is less than that of NAO and semimetallic pads. The surface morphology studies revealed that the metallic pads contained more primary plateaus and smaller amounts of secondary plateaus compared to semimetallic and NAO pads, resulting in better wear resistance characteristics.

Because the market is flooded with various options for brake pad materials, it is imperative that the vehicle manufacturers choose the right pad material with great care not only to ensure the optimal functioning of the braking system but also passenger safety. Mechanical and tribological properties of brake pads contribute greatly to their effectiveness. There is a requirement to choose the proper material for a certain application that has a consistent friction coefficient and reduced wear.

The main purpose of this study in the field of automotive brake friction material is to find an effective material to replace the environmentally hazardous copper in the brake pad formulation.

Cu is used as functional filler in various forms in the friction material formulation. Because of its hazardous impact to the aquatic life, a suitable replacement of Cu is the main focus of this research. Three novel friction composite materials using ground granulated blast furnace slag (GGBFS) as a suitable alternative for Cu were developed by increasing its Wt.% from 5% to 15% in the step of 5%.

The physical, mechanical and chemical properties of the developed friction composites were tested as per the industrial standards. The tribological properties were analyzed as per SAE J661 standard using the chase test rig. Initial studies revealed that the friction composite having 5% GGBFS exhibited better physical, mechanical and chemical properties with excellent frictional performance having minimal fluctuations even at higher temperatures. Nonetheless, the results showed that the friction composite containing 15 Wt.% GGBFS revealed a better wear resistance property compared with the other two composites due to the tribo lubricating layer formation at the frictional interface. Scanning electron microscope analysis was performed to understand the wear mechanism and tribo layer formations through topography studies.

This paper explains the influence of GGBFS as a replacement of barytes in brake pads formulation to enhance the tribological performance.

The purpose of this study was to investigate the use of boric acid as a friction modifier material in brake friction composites and to determine the effect of heat treatment applied during production on braking performance.

The addition of five different amounts of boric acid was balanced with cashew, which is in the friction modifier material group. The samples were produced in the following order: dry mixing, preforming and hot-pressing. The effect of the heat treatment that can be applied after the hot-pressing process on the braking performance was investigated. The tribological and physical properties of the samples were determined using tests performed according to appropriate standards. The microstructures of the friction surfaces were investigated using scanning electron microscopy.

It was observed that the tribological properties of brake friction composites containing 20% by weight of boric acid were improved. It has also been observed that the heat treatment applied after hot pressing increased the friction coefficient of the samples by 7% on average and decreased the specific wear ratio of the samples. When the surface morphologies of the samples are examined, it is seen that the friction layers of the heat-treated samples are wider, and the microvoids and cracks are reduced.

This study showed that boric acid can be used as a friction modifier in brake friction composites. It also revealed the tribological and physical contribution of the applied heat treatment to the composite. Thus, it guides brake friction composite manufacturers in the industry and researchers working in this field.

The purpose of this paper is to develop a mathematical model for optimizing the metal removal rate (MRR) through Response Surface Methodology (RSM). The developed model helps us to analyze the influence of individual input machining parameters (cutting speed, feed rate, weight percentage) on the responses in machining of Al-TiB₂ composite.

RSM is used to optimize the MRR by developing a mathematical model. Three factors, three-level box Behnken design matrix in RSM is employed to carry out the experimental investigation. The “Design Expert 8.0” software is used for regression and graphical analysis of the data are collected. The optimum values of the selected variables are obtained by solving the regression equation and by analyzing the response surface contour plots. Analysis of variance (ANOVA) is applied to check the validity of the model and for finding the significant parameters.

The response surface model developed, helps to calculate the MRR at different input cutting parameters with the chosen range with more than 95 per cent confidence intervals.

The effect of machining parameters on MRR during machining of Al-TiB₂ composites using RSM has not been previously analyzed.

Although situational crisis communication theory (SCCT) is centered on rationality and cognitive information processing, it ignores that people are also driven by irrationality and non-cognitive information processing. The purpose of this study aims to fill this gap by examining how gender stereotypes, based on perceived spokesperson sex influence the public’s perceptions of crisis response messages.

A 2 (industry type: automotive vs daycare industry) × 2 (spokesperson’s sex: male vs female) × 2 (crisis response appeal: rational vs emotional) between-subject online experiment was conducted to examine the effect of gender stereotype in crisis communication.

Results showed that either matching spokesperson sex with sex differed industry or matching sex differed industry with appropriate crisis response appeal can generate a more positive evaluation of the spokesperson and the organization. The results also revealed under which circumstances, the attractiveness of different sex of the spokesperson can either promote or mitigate people’s perceptions of the organization. Furthermore, when people are aware of a spokesperson’s sex, in a female-associated industry, a mismatching effect of a positive violation of a male-related stereotype overrides a matching effect of a female-related stereotype in crisis communication.

This study is among the first to identify how the gender of a spokesperson and industry type affect publics’ crisis response.

THE following list of errata, adjustments and revisions of the actual classification itself, represents all that it has been deemed necessary to note in the way of such alterations, and the changes have been suggested by the experience of users and the discoveries of various librarians. Those who use the scheme should have the changes noted in an interleaved copy of the book, and others may find it desirable to do likewise, pending the appearance of a revised issue which will be published in the near future. Most of the changes are self‐explanatory, and their meaning can be ascertained at once by reference to the S.C. itself. Suggestions and notes of errors will be very gratefully received, as it is only by the vigilance and practical working of many minds that a classification scheme can ever arrive at even reasonable accuracy and completeness.

The purpose of this paper is to examine whether firms use different earnings management approaches when facing financial difficulties and the effects of industry-specialist auditors in constraining those choices. The empirical results suggest that (1) firms with lower risk of business failure but with stronger incentives to adjust earnings upward tend to use real earnings management (REM) income-increasing approaches while (2) at the same time, using discretionary accruals for income-decreasing earnings management, due to constraints imposed by specialist auditors on the use of accrual-based earnings management (AEM). This is consistent with the findings of Chi et al., and the authors do not find similar evidence for the firms with higher risk of failure. Also, (3) regardless of the level of failure risk, firms turn to REM while interestingly, such REM behavior is effectively curbed by industry-leading specialist auditors (specialist auditors with the highest client market share) on financially distressed firms. These results extend the findings of Chi et al. (2011), suggesting that industry-specialist auditors have different tolerance levels for earnings management approaches by firms with different levels of business failure risk. That is, when auditing clients with higher risk of failure, specialist auditors are more likely to maintain higher audit quality through more stringent audit testing and use of more audit staff time to prevent an occurrence of audit failure.

The authors examine earnings management behavior across firms in Taiwan with different levels of business failure risk and the effects of audit partner industry specialization in constraining that behavior. Chi et al. (2011) studied low-risk firms with incentives to adjust earnings upward and found firms use REM when the auditors constrain AEM. The authors extend the work of Chi et al. and observe firms with different levels of failure risk.

The authors find (1) lower risk firms may use discretionary accruals to adjust earnings downward while the authors find no similar evidence for financially distressed firms, (2) lower risk firms may use REM when their industry-specialist auditors curb AEM and (3) the industry leaders among specialist auditors do the same for the financially distressed firms. The results demonstrate the extent to which industry-specialist auditors apply different tolerance levels for earnings management behaviors across firms with different levels of failure risk.

The study contributes to the literature in the following three ways: first, the authors fill a gap in the existing literature by comparing firms with higher risk of business failure to firms with lower risk of business failure to explore the possible difference in the two different kinds of earnings management behavior; second, the authors extend the findings of Chi et al. (2011) and examine whether specialist auditors, when auditing firms with higher risk of business failure, will input more audit effort to constrain their clients' use of REM and third, since business failures have a significant impact on the capital markets and any associated audit failures can have an even greater negative impact on investor confidence, the study provides information useful to auditors and regulators in the formation of salient policy regarding the use of REM by firms experiencing high risk of business failure.

Starting at such a nutritional and health level as probably most people accept as their norm, it is now clearly possible (1) better to ensure a normally prompt development of the young, (2) to induce a higher level of adult vitality and accomplishment, and (3) materially to improve the duration as well as the quality of life, through the guidance of nutritional knowledge in the everyday choice and use of food. Three questions may have suggested themselves: (1) How conclusive are the data supporting such statements as those of the preceding paragraph?; (2) What are the grounds for confidence in the human application of the finding of laboratory animal experimentation in this field?; and (3) With all due reverence for individual human lives, will a longer‐lived population be an advantage? Each of these questions is worthy of a much fuller answer than the space here available permits; and could be answered with much ampler evidence and explanation, but for the present need of extreme condensation. Statistical analysis of the objective, numerically recorded data of laboratory‐controlled experiments shows, at all stages of the life cycle, nutritional improvements upon the initial norms with measured differences so manifold greater than their probable errors as to establish these findings with higher degrees of scientific certainty than probably attach to most of the unquestioned facts of physiology. The least‐expected of the new findings, namely, the extension of the normal adult life‐expectation, is objectively established with 100‐fold greater degree of statistical convincingness than the accepted canons of scientific criticism call for to justify the characterisation of such a finding is “undoubted.” The basal dietary of these experiments is representative of the food supplies upon which a large proportion of our people subsist; and the animal species chiefly used for the full‐life, successive‐generation experiments above mentioned is the rat, chosen primarily because of the many and close resemblances of the chemistry of the nutrition of that species and our own. The only known significant differences are with respect to ascorbic and nicotinic acids; and toward both of these the human species is much more responsive to the level of dietary intake than is the rat. Critical study reveals no reason to discount the above‐noted laboratory findings because of species difference; but, on the contrary, shows strong scientific evidence that the indications obtained from the experiments with rats are well within the probabilities of the nutritional improvement of human lives by intelligent use of our everyday foods. Such nutritional improvement results not only in longer life but also in the living of our lives upon a higher level of health and accomplishment throughout. The “extra time” is not added to the period of senility. It is inserted in the period of the prime, making this a longer fraction of the life cycle. Thus the nutritional improvement brings, to speak in human terms, both a larger number and a larger percentage of years of full accomplishment, and economic and social value, with a smaller proportion of years of dependency. Space does not permit the discussion here of the very real advantages, to the individual, to the world of industrial affairs, and to the nation, of an earlier attainment of full capacity and also a postponement of the onset of old age. How to extend the benefits of the newer knowledge of nutrition, as widely and as promptly as possible is both an economic and an educational problem. If space permitted, an abundance of statistical evidence could be assembled to show: (1) that, independently of educational opportunities, the families with better per capita purchasing power tend to provide themselves with nutritionally better food supplies; and (2) that also, among families exercising the same purchasing power in the same markets, some provide themselves with dietaries which are nutritionally excellent, others only good, and still others only fair. Much can be (and in many places is being) gained either by direct economic measures to increase the purchasing power of low‐income families whether by increase of money income or by making available to them larger supplies of protective foods at lower prices; or by widespread teaching of the nutritive values of foods and the influence of nutritional wellbeing upon health and earning‐power. Needless to say, the communities which have good use of both of these means of improvement may expect to reap the largest benefit. In an unbiased economic view everyone can see that there is opportunity for enormous benefit in using the new knowledge of nutritive values to guide the investment of the many billions of dollars that are annually spent in this country for food; and especially when the choice of food is now known to have greater and more far‐reaching effects upon health and earning power than has hitherto been supposed. But how often bias enters to cloud the economic view! Attempts to teach a more scientific investment of money in food are apt to meet a “vested interest” attitude of resentment from many purveyors of things which science cannot recommend for a higher place in consumers' budgets. And perhaps an even larger number of people “object on principle to,” or subconsciously react against, any attempt to teach discrimination of consumer demand, and any form of governmental paternalism or further extension of “government into business.” In addition to all the bias of an economic or political sort, tradition in itself retards change, especially in matters which come so closely home as does the family food supply. And in the domain of food, as one of the wisest students of nutrition has said, tradition tends to accumulate prejudices quite as often as truths. These and other causes tend somewhat unduly to caution in public teaching of the everyday use of the newer knowledge, which in terms of foods as bought and eaten is: Give fruits, vegetables, and milk in its various forms (including cheese, cream, and ice‐cream, if desired) a larger place in the dietary and food budget. This can be done without “cutting out,” and without too drastically “cutting down,” any other articles of food. As the Nestor of the new knowledge of nutrition has consistently taught: If we cat what we should, we can at the same time eat what we like. Another question sometimes arising is, How can we feel confident of the practical application of present nutritional knowledge when we admit its probable incompleteness by recommending further research? The present writer's answer is that some findings of such far‐reaching importance that their everyday application ought not to be postponed are conclusively established, and the practical advice above suggested is based upon these and is permanently valid. More elaborate and detailed dietary recommendations may well await the findings of such further researches as are briefly suggested below. Both further research and fuller application, neither delayed by waiting upon the other, should be strongly emphasised, especially in view of the present and impending situation. There should be prompt and wide dissemination of present knowledge at all teaching levels. And nothing is so stimulating to education as that research in the same field be actively productive at the same time. The best way to get a hearing, even for the findings now conclusively established, is to have some related new findings to tell. If made in large numbers, with great care, and on a comprehensive plan, further researches with natural foods as the experimental variables might be of great value. More accurate knowledge of the quantitative distribution of certain of the mineral elements and vitamins in foods can be sought with greater assurance of clear‐cut findings, and with certainty that these data will function both in the advancement of science and in the service of human welfare. There is also a field for much valuable research in the measurement of the nutritional availabilities of the mineral and other nutrients of the different articles and types of food, more especially by experimental methods which comply with the actual conditions of normal nutrition. With more precise knowledge of the nutritive values of a wider range of foods, it becomes increasingly practicable to ensure excellence of nutrition without sacrifice either of personal preferences in food selection or of the economic advantages which market fluctuations and seasonal conditions offer. Fortunately, most seasonal food crops are at their best when they are also at their cheapest. The fuller our knowledge of nutrition, the less we need depend upon diversification, but the better we are prepared to gratify a taste for it. The newer knowledge of nutrition is friendly to the fact that “eating has a great vogue as an amusement,” and several foods formerly regarded as luxuries are now seen to be good nutritional investments. The science of nutrition does not seek the sanctification of spinach: it looks with much more favour on many of the things that we find most fun in eating. The new knowledge helps in meeting the problems of both war‐time and peace‐time food supplies; and the findings of further research will doubtless help us all still further to harmonise our appetites and aspirations—to know how to eat both what we want and what will make us most efficient. Both for completeness of scientific explanation and to establish the boundaries of advantageous practical application of the findings, further research is needed even upon two of the three factors which, as mentioned in an earlier section, have already been studied more fully than others by our recently developed methods. As opportunity permits, similar studies should also be made of the long‐time effects of different levels of intake of each nutritionally essential amino acid, mineral element, and vitamin. Meanwhile, the factors which have already been found to be of outstanding importance in experiments upon the entire life cycle should now be studied by similar methods but with starting‐points at different ages so as to ascertain the influence of initial age upon the potentialities for nutritional improvement of the life history. In the planning of all such studies the world‐wide present interest in efficiency and preparedness will tend to give priority to those researches which bear most directly upon problems of the attainment of the fullest fitness, from what‐ever initial age, and the maintenance of optimal capacity for service. Fortunately, such advances of knowledge will service both science and the nation well, however long or short the war, and whatever its aftermath may be. Studies in nutritional rehabilitation deserve also a well‐considered place in the general programme for bringing the new knowledge into the service of all the people. Between the obvious cases of specific deficiency diseases and, on the other hand, the people whose physique and efficiency are within the zone of our present norm, too many even of our American people (and doubtless a higher proportion in most other countries) are handicapped, though we may not know exactly how and why. Many of these people can be rescued from individual and family frustration, and incalculably enhanced in economic and social value to the community and nation, by “enough of the right kinds of food”; and just what this means in more precise terms, how the greatest good can be accomplished with most promptness and efficiency, are problems within the scope of the present‐day methods of research in the chemistry of nutrition. Moreover, the same general type of research reveals good scientific probabilities of improving the chemistry of the internal environment, and thus enhancing the efficiency, of people who are already quite fortunately healthy and efficient.

The purpose of this study is to extend the classical noncentral F-distribution under normal settings to noncentral closed skew F-distribution for dealing with independent samples from multivariate skew normal (SN) distributions.

Based on generalized Hotelling's T² statistics, confidence regions are constructed for the difference between location parameters in two independent multivariate SN distributions. Simulation studies show that the confidence regions based on the closed SN model outperform the classical multivariate normal model if the vectors of skewness parameters are not zero. A real data analysis is given for illustrating the effectiveness of our proposed methods.

This study’s approach is the first one in literature for the inferences in difference of location parameters under multivariate SN settings. Real data analysis shows the preference of this new approach than the classical method.

For the real data applications, the authors need to remove outliers first before applying this approach.

This study’s approach may apply many multivariate skewed data using SN fittings instead of classical normal fittings.

This paper is the research paper and the authors’ new approach has many applications for analyzing the multivariate skewed data.

Trials provide social movements with a public arena that can advance social movement goals. The adversarial structure of a trial gives social movements an opportunity to articulate their grievances and to subject their opponents to cross-examination. The drama associated with trials often attracts media attention, thus creating a broad audience for the movement's message. Moreover, trials can sometimes provide opportunities for collective experiences, bringing together activists, lawyers, experts, and other actors whose combined efforts can both strengthen the movement and promote its goals.