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A feasibility study for a large power transformer reveals several key design issues, each of which is expressible in terms of simple, fundamental field effects. Six generic effects are briefly reviewed and their importance explained. In all cases but one their influence can be estimated, to an accuracy adequate for feasibility purposes, without computation or detailed analysis. They are: mechanical stress due to magnetic fields; electrical breakdown caused by winding capacitance distribution; dielectric breakdown caused by the mixing of different materials, including liquid nitrogen; reduction of critical current density due to internal magnetic fields; the need, or otherwise, for conductor transposition; modelling of field penetration and ac losses in HTc superconductors.

We highlight key assumptions implicit in the models used by academics conducting research on market efficiency. Most notably, many academics assume that investors can borrow unlimited amounts and construct long-short portfolios at zero cost. We relax these assumptions and examine the attractiveness of long-short strategies as stand-alone investments and as a part of a diversified portfolio. Our analysis illustrates that the key benefit of long-short investing is adding diversification to a portfolio beyond what the market provides. We show that as stand-alone investments, nontrivial risk remains in the “hedge” strategies and that the returns generally do not beat the market in a head-to-head contest. Our findings raise questions about the degree of inefficiency in anomaly studies because plausible measures of costs generally offset strategy returns. The ability to achieve greater diversification may be, but is not necessarily, due to market inefficiency. We also highlight the key role of the generally ignored but critically important short interest rebate and show that absent this rebate, the long-short strategies we examine generally yield insignificant returns.

This study documents that high book‐to‐market (value) and low book‐to‐market (glamour) stock prices react asymmetrically to both common and firm‐specific information. Specifically, we find that value stock prices exhibit a considerably slow adjustment to both common and firm‐specific information relative to glamour stocks. The results show that this pattern of diferential price adjustment between value and glamour stocks is mainly driven by the high arbitrage risk borne by value stocks. The evidence is consistent with the arbitrage risk hypothesis, predicting that idiosyncratic risk, a major impediment to arbitrage activity, amplifies the informational loss of value stocks as a result of arbitrageurs’ (informed investors) reduced participation in value stocks because of their inability to fully hedge idiosyncratic risk.

Because mobile manipulators are unable to climb stairs, the elevator operation is a crucial capacity to help those kinds of robot systems work in modern multifloor buildings. Here, the elevator button manipulation is considered as an efficient approach to fulfill that requirement. Previously, some studies presented elevator button recognition algorithms while some others designed schemes for the button manipulation work. However, the mobile robot, the manipulator and the camera in their robot systems are asynchronous. Besides, the time-consuming calibration for the camera is inevitable, especially in changeable environments. This paper aims to present an alternative method for the elevator button manipulation to overcome mentioned shortcomings.

In this paper, the elevator button manipulation is conducted by using the visual-based self-driving mobile manipulator in which the autonomous mobile robot, the manipulator and the camera cooperate more efficiently. Namely, the mobile robot does not need to be located exactly in front of the elevator panel as the manipulator has the ability to adjust the initial frame of the camera based on the system kinematic synchronization. In addition, the proposed method does not require the real world coordinates of elevator buttons, but uniquely using their pixel positions. By doing this, not only is the projection from two-dimensional pixel coordinates to three-dimensional (3D) real world coordinates unnecessary, but also the calibration of the camera is not required.

The proposed method is experimentally verified by using a visual-based self-driving mobile manipulator. This robotic system is the integration of an autonomous mobile robot, a manipulator and a camera mounted on the end-effector of the manipulator.

Because the surface of the elevator button panel is usually mirror-like, the elevator button detection is easily affected by the glare and the brightness of the environmental light condition.

This robot system can be used for the goods delivery or the patrol in modern multifloor buildings.

This paper includes three new features: simultaneously detecting and manipulating elevator buttons without the projection from pixel coordinates to 3D real world coordinates, a kinematic synchronization to help the robot system eliminate accumulated errors and a safe human-like elevator button manipulation.

In the last few years, environmental issues have become a matter of survival. In this sense, e-waste management is among the major problems since it may be a way of mitigating mineral depletion. In this context, the literature lacks e-waste supply chain studies that systematically map supply chain challenges and risks concerning material recovery.

Given this context, the authors' paper conducted a systematic literature review (SLR) to build a framework to identify the constructs of e-waste supply chain risk management.

The paper revealed the theoretical relationship between important variables to achieve e-waste supply chain risk management via a circular economy (CE) framework. These variables include reverse logistics (RL), closed-loop supply chains (CLSC), supply chain risk management, supply chain resilience and smart cities.

The literature contributions of this paper are as follows: (1) a complete list of the risks of the e-waste supply chains, (2) the techniques being used to identify, assess and mitigate e-waste supply chain risks and (3) the constructs that form the theoretical framework of e-waste supply chain risk management. In addition, the authors' results address important literature gaps identified by researchers and serve as a guide to implementation.

The purpose of this paper is to shed light on teachers’ attention to student learning in post-lesson discussions in Lesson Study (LS) by exploring the depth and analytic stance of noticing (van Es, 2011) and by identifying interactions that may extend or narrow the levels of noticing.

The study has dug deeply into post-lesson discussions in the context of two different LS groups at a Norwegian lower secondary school.

The paper provides empirical insights about crucial elements of teachers’ learning processes pertaining to their professional noticing. Sharing of rich descriptions of evidence of student learning appeared to be a necessary foundation for the deepening of the teacher groups’ analytic approach. The study highlights the importance of teacher groups’ openness and attention to the collected data and a shared willingness to go deep into the interpretations. Interthinking and exploratory talk (Littleton and Mercer, 2013) are emphasised as important social interaction and talk modes to deepen the analytic stance and depth of noticing.

Even though this is a small study, it brings to light important knowledge about how interactions in post-research lesson discussions in LS can influence teachers’ professional noticing.

An implication of the study is to design observation forms that capture student learning as tools for teachers’ professional noticing.

This paper fulfils an identified need to investigate teachers’ learning processes in LS, including how interactions within a teacher group influence noticing.

“A Canadian company required information on a process in Switzerland. Since data were too complicated to obtain by mail a vice‐president of the company was assigned to make a trip. The company librarian hearing of this situation accidentally made a search and produced the information from the company's own files.”

A primary tool for managing the democratic risks posed by political donations is disclosure. In Australia, corporate donations are disclosed in government databases. Despite the potential accountability benefits, corporations are not, however, required to report this information in their annual or stand-alone reports. The purpose of this paper is to investigate the quantity and quality of voluntary reporting and seek to add to the nascent theoretical understanding of voluntary corporate political donations.

Corporate donors were obtained from the Australian Electoral Commission database. Annual and stand-alone reports were analysed to determine the quantity and quality of voluntary disclosures and compared to O’Donovan’s (2002) legitimation disclosure response matrix.

Of those companies with available reports, only 25 per cent reported any donation information. Longitudinal results show neither a robust increase in disclosure levels over time, nor a clear relationship between donation activity and disclosure. The findings support a legitimation tactic being applied to political donation disclosures.

The findings suggest that disclosure of political donations in corporate reports should be mandatory. Such reporting could facilitate aligning shareholder and citizen interests; aligning managerial and firm interests and closing disclosure loopholes.

The study extends the literature by evaluating donation disclosures by companies known to have made donations, considering time-series data and theorising the findings.

Explores the impact of marketisation and enterprise restructuring processes on a Polish case study organisation. “Polskie” illustrates that certain western HRM practices are informing the process of restructuring organisations. These new approaches signal managers’ intentions to change attitudes to work and reassert control over the production process. The assessment, development and utilisation of human resources is an integral part of the overall management of the post‐communist enterprise. The field of personnel management is set to assume a key position. A key research question is whether women, as existing practitioners, have been able to augment their position in this growing area of expertise. Discusses whether the process of political and economic reform in Poland has provided an opportunity to improve the employment status of women and identifies reasons for being optimistic, but also highlights several areas for concern.