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The purpose of this paper is to design and construct a low‐cost current‐voltage tester, bearing in mind the short falls of the existing testers and the ever‐increasing price of the testers currently on the market. The I‐V tracer presented in this paper uses a variable external power supply unit (PSU) as the load, in order to obtain the entire operating range of a PV module from open circuit through maximum power to short circuit condition.

The I‐V tracer presented in this paper was divided into three main sections, mainly the data acquisition system (DAS), which comprises an A/D computer card, temperature card, electromechanical relays, current and voltage transducers, aluminum housed resistors and power MOSFETS, the variable load (programmable variable PSU) and finally the signal processing unit. These components were integrated and finally interfaced to a PC.

The results obtained using this system compared with the capacitive tester show a low percentage difference of <1 from the comparative I‐V curves measured. The results measured by the PSU tester are also of high accuracy. The findings also demonstrated the fact that most of the components found in most university laboratories can be used to build the PSU tester and still obtain highly accurate results.

Since some components are semiconductors, which have a limited lifetime, they need to be changed if they fail. Mostly the MOSFETS should be replaced when no switching signal is sent.

This low‐cost PSU tester is suitable for researchers in disadvantaged institutions whose research capabilities are limited due to the high cost of this equipment.

The PSU tester uses a variable power supply as the load to measure PV module I‐V curves. The system is capable of measuring up to eight modules at the same time, making it possible to analyze PV modules within the same time frame.

This model shows the effects of armature reaction in an alternator supplying a variable power‐factor load.

This study aims to develop a multi-material stereolithography (MMSL) technique to directly fabricate a biphasic osteochondral scaffold.

A bespoke prototype MMSL system was developed based on a bottom-up mask projection approach. The system was controlled by a multi-material fabrication algorithm with minimum number of switching cycles during fabrication. A variable-power light source was used to fabricate materials with significantly different curing characteristics. The light-curable poly(ethylene glycol) diacrylate (PEGDA) hydrogel and beta-tricalcium phosphate (β-TCP) ceramic suspension were used for fabricating the biphasic osteochondral scaffold.

The bonding strength of the multi-material interface is shown to be mainly affected by the type of photopolymer, rather than the switching of the materials in MMSL. Lighting power densities of 2.64 and 14.98 mW/cm2 were used for curing the PEGDA hydrogel and the ß-TCP ceramic suspension, respectively. A biphasic osteochondral scaffold with complex interface was successfully fabricated.

This study proposes a potential technical method (MMSL) for manufacturing a complex biphasic osteochondral scaffold composing a PEGDA hydrogel/ß-TCP ceramic composite in a time-efficient and precise manner. The designed bone-cartilage scaffold interface and the surface of the cartilage scaffold can be precisely manufactured.

A STUDY of the economic design and operation of the rigid airship must take account of many variables; power, speed, range, useful load, volume and structure weight—to cite the most obvious—have presumably absolute values which, in combination for a particular duty, produce the most economical whole. With the very limited knowledge of design and operation which we have at present, it is not possible to attempt a comprehensive enquiry, but certain of the simpler aspects of the problem of the economics of the rigid airship can be considered with advantage. The present note is an attempt to discuss, very elementarily, and on what are thought to be reasonable assumptions, the variation of structure weight with gross volume.

Based on data collected over a 15 year period (2000–2015) for 89 countries selected across nine geopolitical regions of the world, the purpose of this paper is to explore the role of economic development and the Hofstede index of national cultures in influencing level of government effectiveness and ICT diffusion; as well as the impact of ICT diffusion on government effectiveness. The level of economic development and a country’s ranking on the E-government index were found significant in explaining ICT diffusion and level of government effectiveness, respectively. But the findings also indicate that only the cultural factors such as Indulgence and long-term orientation (LTO) were quite significant in explaining level of government of effectiveness and ICT diffusion, respectively. The findings conclude that while some cultural factors may provide partial explanations for a country’s level of government effectiveness or ICT diffusion, but for other cultural elements, the path of influence is still unclear and at best debatable. Hence, in light of the growing emphasis placed on it in the literature, the effect of culture is limited and may have been overstated. ICT diffusion, while a necessary tool for administrative efficiency, is only but one piece of a larger puzzle and should be developed in consideration of and in the context of a broader framework of economic development, institutional design and behavioral practices.

This study examines how existing ICT diffusion and infrastructures among a set of 89 countries spread across nine world geopolitical zones has been able to improve their government effectiveness – as measured by their relative scores or rankings on the global “government effectiveness index” over a 15 year period (2000–2015); and also how specific cultural factors may influence the level of ICT diffusion. Drawing data from the United Nations e-Government knowledge database, the United Nations Development Program, the GlobalEconomy.com, as well as other socio-demographic sources, I examine key and associated indicators that influence information technology diffusion and its contributory effects on level of government effectiveness; as well as the impact of national cultures on ICT diffusion.

Overall, the finding from this analysis point to the fact that only two of the Hofstede national culture variables were significant (LTO and Indulgence). The other four national culture variables (Power Distance, Individualism, Masculinity/Femininity and Uncertainty Avoidance) were not. Indulgence has a negative effect on level of government effectiveness, while LTO has a positive effect on ICT diffusion. The other culture variables were not significant in any of the regression models, but they seem to congregate much closer to or around the mean.

This is the only work of its kind that has utilized the seven Hofstede indicators to test for the relationship between culture and technology over a long period of 15 years.

This paper aims to examine the contemporary association between accounting information and a number of measures of systematic (beta) risk that incorporate dynamic market features. The goal is to determine the fundamental accounting drivers of beta and to assess whether their explanatory variable power has changed or declined over time.

Beta estimates are calculated using adjustments for thin‐trading, central tendency, leverage, and time variance. Accounting risk variables are derived from theoretical foundations and prior empirical research, and classified as operating, financial or growth.

Results show a strong association between accounting variables (operating and growth) and systematic risk that is consistent over time, but with some industry and size differences and possible country effects. Accounting variables are able to capture dynamic risk shifts and generally are able to outperform naïve M‐GARCH and industry betas in predicting next year's systematic risk.

Internal management and external decision making enable the development of more efficient ex‐post risk measures, isolating actual risk determinants rather than just determining the level of risk, overcoming the problem that conventional ex‐post measures cannot be used for non‐listed entities, initial public offering firms, or those that do not have sufficient trading history, reduces the noise found in traditional risk estimates that rely on historical security returns, and the development of trading and valuation strategies.

This is the first paper that assesses the association between a range of dynamic risk measures and accounting variables and tests whether this long‐run association has changed over time.

The purpose of this paper is to examine the effects of corporate governance failure, excess remuneration and entrenchment of managers, company variables and corporate governance variables on the company’s financial distress risk (DETR) in the French context.

Using the regression analysis, this paper is based on 201 observations about 67 companies of SBF 120 from 2015 to 2017. Data are collected on the Thomson Reuters database and in the referenced documents, which are published on the internet.

The research findings reveal that firm’s DETR is influenced negatively by excess remuneration and entrenchment of managers. In addition, there is a positive and significant relationship between DETR and company variables (performance and ownership structure) and corporate governance variables (power structure). However, a company’s size and board of directors’ independence do not affect firms’ DETR.

The impact highlighted between remuneration and entrenchment of managers and the financial distress of the company is explained by the intention of managers to work for announcing good short-term performance indicators that are most favorable to them.

The shareholder/manager agency problem can be changed when business performance tends to decline. Certainly, the managerial latitude adopted by the managers is used as an external careerism strategy. Its positive impact on the reduction of the firm’s financial distress can benefit shareholders who aim to sell their securities in the short term.

There is a dearth of literature on what are the factors in terms of leaders’ and followers’ characteristics that impact innovation at the country level. The purpose of this paper is to build theoretical argument and provide empirical evidence of these factors using a cross-cultural mode of study across 56 nations.

The Bayesian modelling technique is used on data from the GLOBE survey.

Innovation at the individual, team and organisational levels has generally been associated with the relationship-motivated leadership, as opposed to task-motivated leadership. This study confirms that this premise holds at the societal level of analysis as well. The second finding is that in terms of followers’ cultural characteristics, out of three variables (power distance, collectivism and performance orientation) tested, only power distance orientation is found to have a predictive relationship with aggregate innovation. The moderator slope analysis unveils a nuanced understanding of how the interaction between leadership styles and followers’ cultural traits impact national innovativeness.

Culture and leadership configurations that bolster innovation need to be studied more thoroughly.

This study has implications for multi-country teams involved in research and development activities.

To our knowledge, this is the first study to unpack leader−follower relationships as predictors of national innovation. A leadership-culture fit perspective is advanced.

The purpose of this paper is to propose and compare two energy management strategies (EMSs). First, a classic method based on frequency separation with fixed limits on fuel cell (FC) power is presented and tested. Then, the improvement of the classic strategy is developed and implemented when the main enhancements are its ease of implementation, hydrogen economy and extending hybrid source lifetime.

The proposed EMS is developed using an online variable power limitation of the FC depending on the battery state of charge while ensuring that the energy of batteries remains in its operating depth of discharge (DOD) range.

In the objective to show the benefits of the developed strategy, a comparative analysis was conducted between two strategies. The simulation and experimental results show the effectiveness and gains obtained by the improved energy management system (IEMS) in terms of fuel economy (13 per cent) and decreasing the applied stress on the FC (22 per cent) which leads to a longer life span of the whole system.

The proposed approach is developed and tested by simulation. To confirm it, a test bench has been assembled as hardware in the loop (HIL) real-time system. The presented experimental results confirm the efficiency and show the providing gains of the IEMS.

Country of origin (COO) effect refers to the influence of COO on consumers' perception and evaluation of a product. This research explores the impact of consumers' power distance on COO effect.

We conducted two experiments to test the relevant hypotheses.

The results indicate that power distance has a polarizing influence on COO effect. That means, for products from countries with good images, the higher the consumers' power distance, the better their evaluation of the products; while for products from countries with poor images, the higher the power distance, the worse their evaluation of the products. The research also finds the moderating effect of consumers' competence–related country-related affect (CRA). When holding positive competence–related CRA, for products from countries with good images, the higher the consumers' power distance, the better their evaluation of the products; for products from countries with poor images, consumers' power distance has no effect. When having negative competence–related CRA, for products from countries with poor images, the higher the consumers' power distance, the worse their evaluation of the products; for products from countries with good images, power distance has no effect.

This study finds that depending on the perception of COO image, power distance not only improves the evaluation of products but also lows such evaluation, reflecting a two-way polarizing feature.