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Thick film superconductors with the nominal composition Bi2Pb0.5Sr2Ca2.5Cu3.5Ox were fired on stainless steel substrates and on alumina substrates covered with silver or gold thick film conductors. Films on stainless steel substrates were semiconducting due to reaction between the superconducting film and oxidised chromium and iron from the steel. Tc(R=0) of films on silver was between 80 K and 90 K while Tc (R=0) on gold was below 60 K. The low Tc (R=0) of films on gold is attributed to the interaction between the gold layer and copper from the superconductor.

Interactions between stainless steel and silver and gold based thick film conductors and YBa2Cu3O7 thick film superconductors were studied by SEM and EDX. The stainless steel reacted with the superconducting layer, forming a Ba‐Fe‐O compound on the interface, while BaO‐depleted YBa2Cu3O7 compound transformed into insulating Y2BaCuO5 compound. When YBa2Cu3O7 is fired on a gold thick film conductor, a thin layer of Y2BaCuO5 compound forms between the conductor and the superconducting film. In the case of a thin Ag conductor, BaO diffused through the silver film and reacted with alumina ceramic to the depth of a few μm. When a thicker silver layer (40–50 μm) was used, diffusion did not occur.

A superconducting material with a composition Y1−xBa2Cu3O7−3/2x − x/2 Bi2O3 (x = 0·1 and 0·2) was synthesised. The influence of Bi2O3 additions on sintering was studied. Preliminary investigations of the Bi‐Sr‐Ca‐Cu‐O system were also made. Thick film pastes, prepared from Y1−xBixBa2Cu3O7 compositions, from the compound YBa2Cu3O7 with 10 w/o addition of Bi2CuO4 and from two compositions in the Bi‐Sr‐Ca‐Cu‐0 system, were fired on Al2O3 and ZrO2 substrates. All thick film materials based on YBa2Cu3O7 compound were superconducting at temperatures above 77 K when fired on ZrO2 substrates, while only a material with the starting composition Y0·8Ba2Cu3O6.7 − 0·1 Bi2O3 reached zero resistivity above 77 K on Al2O3 substrates. Tc (onset) of samples based on the YBa2Cu3O7 compound was around 95 K, and of samples from the Bi‐Sr‐Ca‐Cu‐O system between 95 and 100 K.

A superconducting material with the composition YBa1.8Pb0.2Cu3O7 was synthesised. The influence of PbO addition on the sintering and formation of the superconducting compound YBa2Cu3O7 was investigated. A thick film paste, prepared from prereacted material and an organic vehicle, was fired on Al2O3 and ZrO2 substrates. The resistivity of samples on ZrO2 substrates decreased to zero around 90 K, while samples on Al2O3 substrates did not reach zero resistivity until 77 K, which is probably due to the differences in thermal expansion coefficient between Al2O3 and the superconducting material. Interactions between Pt alloy based thick film conductors and superconducting material were studied.

The importance of formal human resource (HR) practices is widely recognized in management literature, but under-researched in the small business and family firm domain. Previous research indicates that family firms rely more on informal HR practices, based on social networks. However, given the heterogeneity of family firms, one cannot assume that all family firms are reluctant to formalize their HR. As the CEO is the key decision maker who covers HR management in family firms, the effect of the CEO type on formal HR practices will be studied. The paper aims to discuss these issues.

Based on a large-scale survey, resulting in a response of 532 family SMEs, the authors perform a hierarchical regression analysis studying the effect of a family/nonfamily CEO on the use of formal HR practices, introducing several moderating effects: CEO generational stage, tenure and education.

Results indicate that family firms with a family CEO have more formal HR practices than those managed by a nonfamily CEO due to higher levels of goal alignment and intentional trust between the owning family and family CEO. Moreover, family firms managed by first generation family CEOs and family CEOs with a higher education have more formal HR practices.

The findings suggest that family CEOs can be equally or even more able as nonfamily CEOs to run a family firm in a formalized/professionalized manner.

Given the scant amount of research on HR formalization in family firms, even though literature documents performance increasing effects, this study fulfils the need to study the effect of the CEO on HR formalization.

This paper aims to study the effects of MnO₂ on the ZnO–Bi₂O₃-based varistor prepared via flash sintering (FS)

MnO₂-doped ZnO–Bi₂O₃-based varistors were successfully prepared by the FS with a step-wise increase of the .current in 60 s at the furnace temperature <750°C under the direct current electric field of 300 V cm⁻¹. The FS process, microstructure and the electrical performance of ZnO–Bi₂O₃-based varistors were systematically investigated.

The doping of MnO₂ significantly decreased the onset temperature of FS and improved the electrical performance of FS ZnO varistor ceramic. The sample with 0.5 mol% MnO₂ doping shows the highest improvement, with the nonlinear coefficient of 18, the leakage current of 16.82 µA, the threshold voltage of 459 V/mm and the dielectric constant of 1,221 at 1 kHz.

FS is a wonderful technology to enhance ZnO varistors for its low energy consumption, and a short sintering time can reduce grain growth and inhabit Bi₂O₃ volatilize, yet few research studies work on that. In this research, the authors analyzed the FS process and improved the electrical characteristics through MnO₂ doping.

The purpose of this paper was to develop the methodology of thick-film/low temperature co-fired ceramic (LTCC) multilayer thermoelectric microgenerator fabrication including the procedure of silver-nickel thermocouples integration with LTCC.

To miniaturize the structures and to increase the output parameters (generated voltage, electrical power), the microgenerator was designed as multilayer systems. It allows to reduce size of the system and to increase the number of thermocouples integrated inside the structure. It also protects buried thermocouples against exposure to harmful external factors (e.g. moisture, oxidation and mechanical exposures). As a substrate, LTCC was used. For the thermocouples fabrication, thick-film pastes based on silver and nickel were chosen. Ag/Ni thermocouple has nearly three times higher Seebeck coefficient and 30 per cent lower electrical resistance than the combination of Ag/PdAg used in previous works of the author.

A multi-layer thick-film thermoelectric generator based on LTCC and Ag, Ni pastes was fabricated. Thirty Ag/Ni thermocouples were precisely screen-printed on few layers. Thermocouples’ arms are 15 mm long and about 150 μm wide. Interlayer connections (via-holes filled with conductive paste) provided the electrical contact between the layers. The biggest fabricated harvester consisted of 90 miniature thermocouples buried inside the LTCC.

The paper presents the results of research that provided to optimize the co-firing process of the LTCC/Ni set. In the result, the methodology of co-firing of silver-nickel thermocouples and LTCC ceramic was elaborated. Also, the methodology of fabrication of miniature thermoelectric energy harvesters was optimized.

This study aims to devise policies in implementing cash waqf system of Baitul Maal wat Tamwil (BMT) in Indonesia, enabling the BMT to optimize its commercial and social activities to better achieve outreach, sustainability and welfare impact.

This study uses the strategic assumption surfacing and testing (SAST) method, with three groups of knowledgeable respondents, including expert, BMT practitioner and regulator to formulate important and certain policies.

The results show that four types of policies are required to improve cash waqf system of BMT, including 12 internal strategic policies, 15 internal operational policies, 15 external strategic policies and 9 external operational policies, which were found to be within a “certain planning region.” All of these policies have been agreed significantly by each group of respondents, as well as by all respondents combined. The most important-certain policies include Shiddiq, Amanah and professional Nazir, inculcate Islamic values to BMT employees and members, standard operating procedure and standard operating management of cash waqf management, technical assistance for Nazir to manage cash waqf and IT systems for BMT-cash waqf administration.

The qualitative method used has its limitations, which could be improved by incorporating other methods. Moreover, the case and respondents are all Indonesian, so that the results are possibly only applicable to BMTs in Indonesia.

BMTs could adopt these policies in implementing their cash waqf management optimally.

The management of cash waqf by BMT could help improve the social activities of the Baitul Maal directly from social cash waqf and indirectly from productive cash waqf.

To the best of the authors’ knowledge, this is the first study using SAST method to determine policies needed by the BMT to upgrade its cash waqf management producing more social programs for the society.

The purpose of this paper is to rank the users’ attitude on major components of mobile cloud computing (MCC) security and investigate the degree of impact of these components on MCC security as a whole.

Hypotheses were evolved and tested by data collected through an online survey-questionnaire. The survey was administered to 363 users from Chinese organizations. Statistical analysis was carried out and structural equation model was built to validate the interactions.

The eight components of MCC security in the order of importance are as follows: mobile device related, user identity related, deployment model related, application-level security issues, data related, virtualization related, network related and service delivery related. The empirical analysis validates that these security issues are having significant impact on perceived security of MCC.

Constant vigilance on these eight issues and improving the level of user awareness on these issues enhance the overall security.

These issues can be used for designing and developing secured MCC system.

While several previous research has studied various security factors in the MCC security domain, a consolidated understanding on the different components of MCC security is missing. This empirical research has identified and ranked the major components of MCC security. The degree of impact of each of these components on overall MCC security is identified. This provides a different perspective for managing MCC security by explaining what components are most important.

This study/ paper aims to empirically examine the user attitude on perceived security of enterprise systems (ES) mobility. Organizations are adopting mobile technologies for various business applications including ES to increase the flexibility and to gain sustainable competitive advantage. At the same time, end-users are exposed to security issues when using mobile technologies. The ES have seen breaches and malicious intrusions thereby more sophisticated recreational and commercial cybercrimes have been witnessed. ES have seen data breaches and malicious intrusions leading to more sophisticated cybercrimes. Considering the significance of security in ES mobility, the research questions in this study are: What are the security issues of ES mobility? What are the influences of users’ attitude towards those security issues? What is the impact of users’ attitude towards security issues on perceived security of ES mobility?

These questions are addressed by empirically testing a security model of mobile ES by collecting data from users of ES mobile systems. Hypotheses were evolved and tested by data collected through a survey questionnaire. The questionnaire survey was administered to 331 users from Chinese small and medium-sized enterprises (SME). The data was statistically analysed by tools such as correlation, factor analysis, regression and the study built a structural equation model (SEM) to examine the interactions between the variables.

The study results have identified the following security issues: users’ attitude towards mobile device security issues; users’ attitude towards wireless network security issues; users’ attitude towards cloud computing security issues; users’ attitude towards application-level security issues; users’ attitude towards data (access) level security issues; and users’ attitude towards enterprise-level security issues.

The study results are based on a sample of users from Chinese SMEs. The findings may lack generalizability. Therefore, researchers are encouraged to examine the model in a different context. The issues requiring further investigation are the role of gender and type of device on perceived security of ES mobile systems.

The results show that the key security issues are related to a mobile device, wireless network, cloud computing, applications, data and enterprise. By understanding these issues and the best practices, organizations can maintain a high level of security of their mobile ES.

Apart from understanding the best practices and the key issues, the authors suggest management and end-users to work collaboratively to achieve a high level of security of the mobile ES.

This is an empirical study conducted from the users’ perspective for validating the set of research hypotheses related to key security issues on the perceived security of mobile ES.