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The aim of this paper is to better understand the generation and transmission mechanism of the electromagnetic acoustic transducer (EMAT).

A semi-analytical method was used to calculate the Lorentz force. Both the hypothetical magnetic field mirror method and the diffusion equation were adopted to solve the eddy current distribution by variables separation method in time domain. A three-dimension magnetostatic finite element model was used to calculate the static magnetic field and the relative permeability. And an experimental platform with a piezoelectric probe to generate and an EMAT to receive, the ultrasonic wave was set up to verify the distribution of the Lorentz force.

The Lorentz force at different time and in different positions of the steel plate can be easily calculated. The experimental results show a good agreement with the analytical results.

The accurate prediction of the Lorentz force provides an insight into the physical phenomenon of EMAT and a powerful tool to design optimum EMAT.

Acoustic signals of the underwater targets are susceptible to noise, reverberation, submarine topography and biology, therefore it is difficult to precisely locate underwater targets. This paper proposes a new underwater Hanbury Brown-Twiss (HBT) interference passive localization method. This study aims to achieve precise location of the underwater acoustic targets.

The principle of HBT interference with ultrasensitive detection characteristics in optical measurements was introduced in the field of hydroacoustics. The coherence of the underwater target signal was analyzed using the HBT interference measurement principle, and the corresponding relationship between the signal coherence and target position was obtained. Consequently, an HBT interference localization model was established, and its validity was verified through simulations and experiments.

The effects of different array structures on the localization performance were obtained by simulation analysis, and the simulations confirmed that the HBT method exhibited a higher positioning accuracy than conventional beamforming. In addition, the experimental analysis demonstrated the excellent positioning performance of the HBT method, which verified the feasibility of the proposed method.

This study provides a new method for the passive localization of underwater targets, which may be widely used in the field of oceanic explorations.

For most companies, growth measures such as asset growth are positively correlated with accrual measures. Just like investment in fixed assets, current accrual represents one form of investment and is an integral part of a firm’s business growth. This makes it difficult to distinguish between the growth-based and earnings quality-based interpretations of the accrual effects, because high accruals can represent both high growth and inflated earnings. The purpose of this paper is to add to the literature by examining an issue that has not received much attention: the correlation between asset growth and accruals and its implication on stock return predictability. The authors address the issue using Fama and Macbeth’s (1973) cross-sectional regressions that are conditional on the correlations between the two variables.

The authors partition firms based on whether the correlation between current accrual and asset growth in the past five years is positive (ρ+) or negative (ρ−). The authors refer to these two types of firms such as “positive correlation” and “negative correlation” groups. For both groups, the authors examine whether firms with higher asset growth and higher accruals are associated with lower future stock returns. The authors implement Fama and MacBeth’s cross-sectional regressions incorporating the effect of correlations between growth and accrual measures. In addition, the authors regress hedge portfolio returns on Fama and French (1993) three-factor and Fama and French (2015) five-factor models to see if the intercepts (a’s) from these regressions are significantly different from 0.

For each year, the authors partition firms based on whether the correlation between asset growth and current accrual is positive or negative. For both the “positive correlation” and “negative correlation” firms, the authors examine the association between accruals and future stock returns. The authors find that accruals remain strong in predicting future stock returns for both groups. The accrual effects from the “negative correlation” group cannot be attributed to the growth-based hypothesis because for these firms, when accruals are high, growth measures tend to be relatively low and vice versa. The effects are most likely driven by the alternative hypothesis that investors overvalue the accrual part of earnings.

There exist a few issues when investors actually implement these strategies. These include liquidity costs, institutional holdings and short sale constraints. Lesmond (2008) concludes that the bulk of the trading profits is derived from the short side of the trade, but that this position suffers from high liquidity costs that reduces institutional holdings with consequent short sale constraints. The net gains after taking into account these issues remain an open question be addressed in the future.

The empirical results indicate that investors can do an implementable portfolio strategy of going long for a year on an initially equally weighted lowest asset growth (accrual) decile portfolio and going short for a year on an initially equally weighted highest asset growth (accrual) decile portfolio, which produces significant abnormal returns. The results further show that these abnormal returns can be improved if investors classify stocks into “the positive correlation” and “negative correlation” groups and implement trading similar trading strategies.

The empirical evidence finds that firm-year observations that exhibit a negative correlation between growth and accrual measures represents a significant 30 percent of the total firm-year observations during the sample period from July 1974 to June 2017. This highlights the necessity to undertake a detailed analysis on the issue. The authors continue to find accrual effects among these groups of firms. Therefore, the accrual effect cannot be attributed to the diminishing marginal return hypothesis. This is the main contribution of the paper.

The purpose of this paper is to show that multivariate t-distribution assumption provides a better description of stock return data than multivariate normality assumption.

The EM algorithm is applied to solve the statistical estimation problem almost analytically, and the asymptotic theory is provided for inference.

The authors find that the multivariate normality assumption is almost always rejected by real stock return data, while the multivariate t-distribution assumption can often be adequate. Conclusions under normality vs under t can be drastically different for estimating expected returns and Jensen’s αs, and for testing asset pricing models.

The results provide improved estimates of cost of capital and asset moment parameters that are useful for corporate project evaluation and portfolio management.

The authors proposed new procedures that makes it easy to use a multivariate t-distribution, which models well the data, as a simple and viable alternative in practice to examine the robustness of many existing results.

Gives an in depth view of the strategies pursued by the world’s leading chief executive officers in an attempt to provide guidance to new chief executives of today. Considers the marketing strategies employed, together with the organizational structures used and looks at the universal concepts that can be applied to any product. Uses anecdotal evidence to formulate a number of theories which can be used to compare your company with the best in the world. Presents initial survival strategies and then looks at ways companies can broaden their boundaries through manipulation and choice. Covers a huge variety of case studies and examples together with a substantial question and answer section.

Man has been seeking an ideal existence for a very long time. In this existence, justice, love, and peace are no longer words, but actual experiences. How ever, with the American preemptive invasion and occupation of Afghanistan and Iraq and the subsequent prisoner abuse, such an existence seems to be farther and farther away from reality. The purpose of this work is to stop this dangerous trend by promoting justice, love, and peace through a change of the paradigm that is inconsistent with justice, love, and peace. The strong paradigm that created the strong nation like the U.S. and the strong man like George W. Bush have been the culprit, rather than the contributor, of the above three universal ideals. Thus, rather than justice, love, and peace, the strong paradigm resulted in in justice, hatred, and violence. In order to remove these three and related evils, what the world needs in the beginning of the third millenium is the weak paradigm. Through the acceptance of the latter paradigm, the golden mean or middle paradigm can be formulated, which is a synergy of the weak and the strong paradigm. In order to understand properly the meaning of these paradigms, however, some digression appears necessary.

Aligning the project management methodology (PMM) to a particular project is considered to be essential for project success. Many outsourced software projects fail to deliver on time, budget or do not give value to the client due to inappropriate choice of a PMM. Despite the increasing range of available choices, project managers frequently fail to seriously consider their alternatives. They tend to narrowly tailor project categorization systems and categorization criterion is often not logically linked with project objectives. The purpose of this paper is to develop and test a contingency fit model comparing the differences between critical success factors (CSFs) for outsourced software development projects in the current context of traditional plan-based and agile methodologies.

A theoretical model and 54 hypotheses were developed from a literature review. An online Qualtrics survey was used to collect data to test the proposed model. The survey was administered to a large sample of senior software project managers and practitioners who were involved in international outsourced software development projects across the globe with 984 valid responses.

Results indicate that various CSFs differ significantly across agile and traditional plan-based methodologies, and in different ways for various project success measures.

This study is cross-sectional in nature and data for all variables were obtained from the same sources, meaning that common method bias remains a potential threat. Further refinement of the instrument using different sources of data for variables and future replication using longitudinal approach is highly recommended.

Practical implications of these results suggest project managers should tailor PMMs according to various organizational, team, customer and project factors to reduce project failure rates.

Unlike previous studies this paper develops and empirically validates a contingency fit model comparing the differences between CSFs for outsourced software development projects in the context of PMMs.

Man has been seeking an ideal existence for a very long time. In this existence, justice, love, and peace are no longer words, but actual experiences. How ever, with the American preemptive invasion and occupation of Afghanistan and Iraq and the subsequent prisoner abuse, such an existence seems to be farther and farther away from reality. The purpose of this work is to stop this dangerous trend by promoting justice, love, and peace through a change of the paradigm that is inconsistent with justice, love, and peace. The strong paradigm that created the strong nation like the U.S. and the strong man like George W. Bush have been the culprit, rather than the contributor, of the above three universal ideals. Thus, rather than justice, love, and peace, the strong paradigm resulted in in justice, hatred, and violence. In order to remove these three and related evils, what the world needs in the beginning of the third millenium is the weak paradigm. Through the acceptance of the latter paradigm, the golden mean or middle paradigm can be formulated, which is a synergy of the weak and the strong paradigm. In order to understand properly the meaning of these paradigms, however, some digression appears necessary.

This systematic literature review analyses the determinants and consequences of executive compensation-related shareholder activism and say-on-pay (SOP) votes. The review covers 71 empirical articles published between January 1995 and September 2017. The studies are reviewed within an empirical research framework that separates the reasons for shareholder activism and SOP voting dissent as input factor on the one hand and the consequences of shareholder pressure as output factor on the other. This procedure identifies the five most important groups of factors in the literature: the level and structure of executive compensation, firm characteristics, corporate governance mechanisms, shareholder structure and stakeholders. Of these, executive compensation and firm characteristics are the most frequently examined. Further examination reveals that the key assumptions of neoclassical principal agent theory for both managers and shareholders are not always consistent with recent empirical evidence. First, behavioral aspects (such as the perception of fairness) influence compensation activism and SOP votes. Second, non-financial interests significantly moderate shareholder activism. Insofar, we recommend integrating behavioral and non-financial aspects into the existing research. The implications are analyzed, and new directions for further research are discussed by proposing 19 different research questions.

Presents a special issue, enlisting the help of the author’s students and colleagues, focusing on age, sex, colour and disability discrimination in America. Breaks the evidence down into manageable chunks, covering: age discrimination in the workplace; discrimination against African‐Americans; sex discrimination in the workplace; same sex sexual harassment; how to investigate and prove disability discrimination; sexual harassment in the military; when the main US job‐discrimination law applies to small companies; how to investigate and prove racial discrimination; developments concerning race discrimination in the workplace; developments concerning the Equal Pay Act; developments concerning discrimination against workers with HIV or AIDS; developments concerning discrimination based on refusal of family care leave; developments concerning discrimination against gay or lesbian employees; developments concerning discrimination based on colour; how to investigate and prove discrimination concerning based on colour; developments concerning the Equal Pay Act; using statistics in employment discrimination cases; race discrimination in the workplace; developments concerning gender discrimination in the workplace; discrimination in Japanese organizations in America; discrimination in the entertainment industry; discrimination in the utility industry; understanding and effectively managing national origin discrimination; how to investigate and prove hiring discrimination based on colour; and, finally, how to investigate sexual harassment in the workplace.