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The aim of this paper is to explore the potential of particle swarm optimization (PSO) methods for minimizing the sidelobe levels (SLL) and placing null at arbitrary angles of a nonlinear antenna array.

An improved PSO algorithm is designed.

The improved PSO method is an efficient and robust global optimizer for minimizing the SLL and placing null at arbitrary angles of a nonlinear antenna array.

Some improvements, such as the design of some new formulae for both position and velocity updating, the introduction of an age variable, and the devise of an intensification searches using the cross entropy method, are proposed.

Meyer Waxman and William Chen, staff research scientists of the Institute for Basic Standards, US National Bureau of Standards, have recently developed a new pressure transducer that enables the accurate measurement of the pressure of corrosive gases over wide temperature and pressure ranges. The research was supported in part by the US Atomic Energy Commission.

The purpose of this paper is to use the proposed algorithm for the fast adaptation of the antenna array radiation pattern on the particular scenario of the incoming signals. The fitness function to be minimized includes the precise estimation of signals’ arrival angles, setting the deep nulls in the directions of the interfering signal, the reduction of the main lobe’s width and the reduction of side lobes.

Unlike conventional adaptive algorithms, the proposed algorithm allows synthesis of radiation patterns in the case of a larger number of incident desired and interfering signals. The proposed method also reduces the width of the dead zone.

In this paper a comparison of the results obtained from the chaotic beamforming algorithm with the results obtained by using the Sequential Quadratic Programming method is presented.

The chaotic beamforming algorithm is proposed here. It is based on the optimization of the least mean square and on the variable step-size least mean square algorithms, using chaos theory for synthesis of the radiation pattern of the linear antenna array.

The purpose of this paper is to report the investigations on the potential of a new evolutionary algorithm based on probabilistic models – the quantum-inspired evolutionary algorithm (QEA) in solving inverse problems.

An improved QEA.

The proposed algorithm is an efficient and robust global optimizer for solving inverse problems.

To enhance the convergence speed without compromising the diversity performances of the populations, a new definition of global information sharing is introduced and implemented. To guarantee the balance between exploration and exploitation searches, a different migration strategy and formula, as well as a novel formulation for adaptively updating the rotation angle, are developed.

The purpose of this paper is to present and solve the problem of adaptive beamforming (ABF) for a uniform linear array (ULA) as an optimization problem. ABF mainly concerns with estimation of weights of antenna array so as to direct the major lobe in the direction of desired user and nulls in the direction of interfering signals with reduced side lobe level (SLL).

The potential of gravitational search algorithm is explored to optimize multi-objective fitness function for ABF using MATLAB software.

The performance of the algorithm has been compared by considering different number of interference signals at different power levels. The proposed algorithm presents good convergence rate and accurate steering of main lobe and nulls with reduced SLL compared to the well-known ABF technique, namely, minimum variance distortionless response (MVDR) and previously reported results. The simulation results are presented in tabular form.

The present work is limited to simulation. The researchers are encouraged to solve the problem of ABF using the proposed approach in hardware.

The application of proposed algorithm is to optimize multi-objective function for ABF with reduced SLL in linear antenna arrays.

Since the initiation of the share split reform by the Chinese Securities Regulatory Commission (CSRC) in 2005, the private placement has become the major source of raising equity after IPO. The purpose of this paper is to investigate why listed firms in China prefer private placements compared to other options of raising capital.

The ordinary least squares regression, the piecewise regression and the cross‐sectional regression analysis were undertaken to investigate the determinants and characteristics of the seasoned‐equity offerings announcement effects. Probit regression analysis was taken to estimate the probability of a firm choosing private placements.

The authors find positive significant announcement abnormal returns for private placement. The findings also indicate that operating performance deteriorates immediately after announcement and poor operating performance is more likely to be contributed by large size portfolios, which suggests size effect.

The paper's evidence contributes to an understanding of the wider implication of the share split reform undertaken by the CSRC.

The paper provides insights for policy makers in China and around the world who have and wish to adopt similar practices within their jurisdictions. Similar research can be conducted in other emerging markets to enable better understanding and implications of seasoned equity offerings on firm financial performance.

The paper is novel in regard to the data and the wider research paradigm used.

Black British minority ethnics (BME) students are nationally underachieving in comparison to their Ethnic Chinese and White peers, showing typically a 16 per cent graduate attainment gap in the UK. Previous research has suggested that the attainment gap could be explained by BME student disengagement, as the students typically commute from family home to University, and they work part time. However, peer-assisted learning (PAL) has been shown to have a positive impact on addressing and resolving student alienation and disengagement. However, a question still remains regarding whether student perceptions hold up to statistical analysis when scrutinised in comparison to similar cohorts without PAL interventions. The paper aims to discuss these issues.

This paper presents the results of a statistical study for two cohorts of students on engineering courses with a disproportionately high representation of BME students. The research method involved a statistical analysis of student records for the two cohorts to ascertain any effect of correlation between: PAL; student ethnicity; and student parental employment on student academic performance and placement attainment.

The results indicate that PAL has no significant impact on the academic performance; however, PAL has a positive impact on the placement/internship attainment for BME students and students from parental households with parents in non-managerial/professional employment.

The research limitations are that the cohorts are small, but more equal diverse mix of different social categories than any other courses. However, as the cohorts are less than 30 students, comparing social categories the data sets are small to have absolute confidence in the statistical results of academic performance. Even the t-test has its limitations as the subjects are human, and there are multiple personal factors that can impact an individual academic performance; therefore, the data sets are heterostatic.

The results highlight that there is need for pedagogy interventions to support: ideally all BME students from all social categery to secure placements; BME students who are unable to go on placement to gain supplementary learning that has the same impact on their personal development and learning as placement/internship experience; and White students from managerial/professional family households to engage more in their studies.

Not addressing and providing appropriate pedagogy interventions, in the wider context not addressing/resolving the BME academic and placement attainment gap, a set of students are being disadvantaged to their peers through no fault of their own, and compounding their academic attainment. As academics we have a duty to provide every opportunity to develop our student attainment, and as student entry is generally homogeneous, all students should attain it.

Previous research evaluation of PAL programmes has focused on quantitative students surveys and qualitative semi-structured research interviews with students on their student engagement and learning experience. On the other hand, this paper evaluates the intervention through conducting a quantitative statistical analysis of the student records to evaluate the impact of PAL on a cohort’s performance on different social categories (classifications) and compares the results to a cohort of another group with a similar student profile, but without PAL intervention implementation.

The purpose of this paper is to develop a “good fit” for garments for customer satisfaction, comfort, and functionality as well as a manufacturer's success and reputation.

This paper reviews and evaluates garments on a live fit model and makes recommendations for the acceptance or modification of the garment for production. As more manufacturing, product development, and designing responsibilities continue to take place globally, alternatives to the traditional fit analysis are under consideration.

Fit analysis using live and three‐dimensional scan models as an alternative to the traditional fit analysis are under consideration.

This paper evaluates garments on a live fit model and makes recommendations for the acceptance or modification of the garment for production.

Drawing on human capital theory and sustainable career theory, this paper aims to explore the impact of undertaking an industrial placement on the “Great Eight” competencies as perceived by university students and line managers.

618 students and their line managers across three cohorts (pre-COVID-19) took part in a longitudinal quantitative study. Students completed a three-wave questionnaire at the placement's start, middle, and end. Line managers completed the questionnaire during waves two and three to offer 360-degree feedback. Descriptive statistics and repeated measures ANOVA were applied to the dataset.

The impacts of undertaking a placement were highly variable for different competencies at the sub-scale level, although at the eight-scale level, the nuance was less pronounced. However, students self-perceived that all eight competencies increased between the start and end of the placement. Surprisingly, line managers perceived students' competencies to be higher than perceived by the students.

The value of undertaking a placement is often poorly measured (e.g. satisfaction) rather than competency-based outcomes, which can lead to conclusions that are overly simplistic and difficult to use in practice. Theoretically, this study advances understanding of human capital theory and sustainable career theory by understanding the role placements can play in developing human capital and preparing university students for sustainable careers. Practically, the findings of this study can help to close the university–industry skills gap by informing curriculum and placement scheme design and supporting students to acquire personal resources and signal these to prospective employers as an antecedent to career sustainability.

This study identifies the factors responsible for obtaining price premium on privately placed equity in a developing market.

We examine a unique data set of a special case of private placement of equity, Qualified Institutional Placement (QIP) in India purchased at a premium. The study analyzed 188 equity issues offered between September 2006 and December 2014. On average, we find that QIP issues received a price premium of 4.38%. The study employed binary probit and ordinary least square regression models to analyze the probability and magnitude of the premium.

The study attributes the price premium of QIP to certification effect through group affiliation, signaling through promoters' ownership and monitoring effect through existing institutional investors. These factors influence the probability of premium for QIP issues. However, group affiliation and institutional ownership do not significantly influence the magnitude of the premium.

The private placement of equity is usually offered at a discount. Our findings contribute to the existing literature by evaluating the premium obtained on private placement as a unique scenario in emerging market supported through certification hypothesis, monitoring hypothesis and signaling.