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The purpose of this paper is to analyze the effect of lanthanum (La) doping on the microstructure and mechanical properties of tin-silver-copper (SAC) alloys and to find out an optimum La doping concentration upon which the best set of the desirable properties can be possible. SAC tertiary Pb-free solders are thought to be the best substitutes for Pb-based solders but have limitations due to their coarse microstructure.

Three samples with varied La concentrations were synthesized from pure metals. SAC with various concentrations of doped La were studied in detail. Scanning electron microscopy images were studied and were further analyzed by the ImageJ software to measure the average intermetallic compounds (IMCs) size. Optical microscopy was used to study the grains. MTS tensile machine was used determine out the mechanical properties. All the analysis was done before and after thermal aging. Finally, an optimum La doping concentration was found.

By doping a suitable concentration of La in SAC, the average IMCs size as well as grain size was greatly reduced. Yield stress and tensile strength were quite improved as a result. Unlike previous studies, ductility was not lowered. Impact toughness was seen to be significantly improved. Finally, an optimum La doping concentration was found to be 0.3 per cent by weight, as beyond this, ductility drops rapidly.

The optimum La doping concentration in SAC resulted in a much refined microstructure and a very good set of the desirable properties, including yield stress, tensile strength, ductility, impact toughness and expectedly creep and fatigue resistances, for the first time.

Cybersecurity vulnerabilities are often due to human users acting according to their own ethical priorities. With the goal of providing tailored training to cybersecurity professionals, the authors conducted a study to uncover profiles of human factors that influence which ethical principles are valued highest following exposure to ethical dilemmas presented in a cybersecurity game.

The authors’ game first sensitises players (cybersecurity trainees) to five cybersecurity ethical principles (beneficence, non-maleficence, justice, autonomy and explicability) and then allows the player to explore their application in multiple cybersecurity scenarios. After playing the game, players rank the five ethical principles in terms of importance. A total of 250 first-year cybersecurity students played the game. To develop profiles, the authors collected players' demographics, knowledge about ethics, personality, moral stance and values.

The authors built models to predict the importance of each of the five ethical principles. The analyses show that, generally, the main driver influencing the priority given to specific ethical principles is cultural background, followed by the personality traits of extraversion and conscientiousness. The importance of the ingroup was also a prominent factor.

Cybersecurity professionals need to understand the impact of users' ethical choices. To provide ethics training, the profiles uncovered will be used to build artificially intelligent (AI) non-player characters (NPCs) to expose the player to multiple viewpoints. The NPCs will adapt their training according to the predicted players’ viewpoint.

The purpose of this study is to fabricate an ultraviolet (UV) metal-semiconductor-metal (MSM) photodetector based on zinc oxide nanorods (ZnO NRs) grown on seeded silicon (Si) substrate that was prepared by a low-cost method (drop-casting technique).

The drop-casting method was used for the seed layer deposition, the hydrothermal method was used for the growth of ZnO NRs and subsequent fabrication of UV MSM photodetector was done using the direct current sputtering technique. The performance of the fabricated MSM devices was investigated by current–voltage (I–V) measurements. The photodetection mechanism of the fabricated device was discussed.

Semi-vertically high-density ZnO (NRs) were effectively produced with a preferential orientation along the (002) direction, and increased crystallinity is confirmed by X-ray diffraction analysis. Photoluminescence results show a high UV region. The fabricated MSM UV photodetector showed that the ZnO (NRs) MSM device has great stability over time, high photocurrent, good sensitivity and high responsivity under 365 nm wavelength illumination and 0 V, 1 V, 2 V and 3 V applied bias. The responsivity and sensitivity for the fabricated ZnO NRs UV photodetector are 0.015 A W-1, 0.383 A W-1, 1.290 A W-1 and 1.982 A W-1 and 15,030, 42.639, 100.173 and 334.029, respectively, under UV light (365 nm) illumination at (0 V, 1 V, 2 V and 3 V).

This paper uses the drop-casting technique and the hydrothermal method as simple and low-cost methods to fabricate and improve the ZnO NRs photodetector.

Financial protection of households against catastrophic healthcare expenditure (CHE) is defined as one of the main goals in health systems. The purpose of this paper is to measure and decompose socioeconomic inequality in CHE among households in Kermanshah province, Western of Iran.

This cross-sectional study was carried out among 1,188 households in 2017. Data were extracted from the Household Income and Expenditure Survey which is conducted by the Statistical Center of Iran. The CHE is defined as household healthcare expenditure greater than or equal to the 40 percent of household’s “capacity to pay.” The concentration curve and the Wagstaff (W) and Erreygers (E) indexes were used to illustrate and measure the extent of socioeconomic inequality in CHE. In addition, the authors decomposed the W and E indexes to identify the main determinants of socioeconomic inequality in CHE.

The results indicated that the prevalence of CHE among households was 4.12 percent (95% confidence interval (CI): 3.13 to 5.42 percent). The estimated value of the W and E indexes were −0.2849 (95% CI: −0.4493 to −0.1205) and −0.0451 (95% CI: −0.0712 to −0.0190), respectively; suggesting the concentration of CHE prevalence among the poor households. Decomposition analyses indicated socioeconomic status as the most important factor contributing to the concentration of CHE among the poor. In contrast, health insurance coverage was found to increase the concentration of CHE among the rich in Iran.

The current study demonstrated a higher concentration of CHE among the poor households in Kermanshah province. These results call for the government’s efforts to reduce healthcare expenditure among socioeconomically disadvantaged populations. Further studies are required to understand the mechanisms through which health insurance coverage increased the probability of CHE among rich in Kermanshah province.

The purpose of this paper is to analyze electromagnetic performance and develop an analytical approach to find the suitable coil combination and no-load flux linkage of the proposed hybrid excited consequent pole flux switching machine (HECPFSM) while minimizing the drive storage and computational time which is the main problem in finite element analysis (FEA) tools.

First, a new HECPFSM based on conventional consequent pole flux switching permanent machine (FSPM) is proposed, and lumped parameter magnetic network model (LPMNM) is developed for the initial analysis like coil combination and no-load flux linkage. In LPMNM, all the parts of one-third machine are modeled which helps in reduction of drive storage, computational complexity and computational time without affecting the accuracy. Second, self and mutual inductance are calculated in the stator, and dq-axis inductance is calculated using park transformation in the rotor of the proposed machine. Furthermore, on-load performance analysis, like average torque, torque density and efficiency, is done by FEA.

The developed LPMNM is validated by FEA via JMAG v. 19.1. The results obtained show good agreement with an accuracy of 96.89%.

The proposed HECPFSM is developed for high-speed brushless AC applications like electric vehicle (EV)/hybrid electric vehicle (HEV).

The proposed HECPFSM offers better flux regulation capability with enhanced electromagnetic performance as compared to conventional consequent pole FSPM. Moreover, the developed LPMNM reduces drive storage and computational time by modeling one-third of the machine.

The purpose of this study is to develop a conceptual framework for defining the notion of “physical integration” regarding the Iranian bazaar as the main component in the structure of traditional Iranian cities. Applying this conceptual framework to the historical bazaars in the cities of Kerman and Shiraz, this study seeks to pave the way for restoring the physical integrity of such historical districts.

The research was conducted in two phases. First, there was a review of the theoretical background of physical integration followed by the analysis of the corresponding qualitative contents and the validation of the proposed conceptual framework as confirmed by 15 local experts. The second phase tested the validated framework in two case studies based on maps, historical documents and field observations.

The findings show that the physical integration of historical bazaars can be undertaken in morphological, visual-aesthetic and functional aspects. The proposed conceptual framework is capable of dealing with the different aspects of physical integration in historical districts on a meso-scale.

The theoretical implications of this study concerning the physical integration of traditional bazaars address urban design, urban planning and multi-disciplinary historical geography. The study also has practical implications for the integration of bazaars in historical urban regeneration projects via design guidelines.

This study emphasizes the importance of physical integration as a multi-dimensional concept, facilitating it to deal with the physical quality and the characteristics of historical districts, particularly bazaars. It also highlights the role of the Iranian bazaar as a unifying structure in the historical districts.

The results of a study carried out to identify the problems and issues arising in the electric distribution system of the Karachi Electric Supply Corporation are presented. The authors are particularly concerned with failures of supply and the principle reasons for those failures are discussed, particularly the domestic overloading problem. Recommendations are made with a view to increasing the reliability, efficiency and effectiveness of the system. It is estimated that the implementation of the recommendations could reduce the number of fault complaints by half and also result in savings in fuel costs of the order of Rs. 1.25 million (approx. £55,000) per annum in the operation of the maintenance teams.

This article seeks to understand how live-streaming technology (i.e. interactivity and effective use of live-streaming shopping’s information presentation tool) impacts consumers’ credibility perception regarding live streamers.

The authors empirically examined their hypotheses with data (n = 405) collected from a survey of consumers who engage in live-streaming shopping.

The results demonstrate that vicarious learning strategies (both coactive and independent) can shape consumers’ benefit perceptions (i.e. virtual presence and psychological proximity), and further have a positive effect on consumers’ personal value (i.e. perceived live streamer credibility). Furthermore, the consumers’ perception of the live streamers’ credibility positively affects their purchase intention and ultimately influences their purchase behavior.

Building on the vicarious learning theory and means-end chain (MEC) model, this study investigates the mechanism of the IT features of live-streaming shopping in reducing consumers’ uncertainty about live streamers. This study reveals the value of vicarious learning experiences in reducing consumers’ uncertainty and further enhancing their purchase behavior.

The purpose of this paper is to investigate the structural, electronic and optical properties of pure zinc oxide (ZnO) and transition metal (Tm)-doped ZnO using Tm elements from silver (Ag) and copper (Cu) by a first-principles study based on density functional theory (DFT) as implemented in the pseudo-potential plane wave in CASTEP computer code.

The calculations based on the generalized gradient approximation for Perdew-Burke-Ernzerhof for solids with Hubbard U (GGA-PBEsol+U) were performed by applying Hubbard corrections U_d = 5 eV for Zn 3d state, U_p = 9 eV for O 2p state, U_d = 6 eV for Ag 4d state and U_d = 9.5 eV for Cu 3d state. The crystal structure used in this calculation was hexagonal wurtzite ZnO with a space group of P63mc and supercell 2 × 2 × 2.

The total energy was calculated to determine the best position for Ag and Cu dopants. The band structures and density of states show that Tm-doped ZnO has a lower bandgaps value than pure ZnO because of impurity energy levels from Ag 4d and Cu 3d states. In addition, Ag-doped ZnO exhibits a remarkable enhancement in visible light absorption over pure ZnO and Cu-doped ZnO because of its lower energy region and extended wavelength spectrum.

The results of this paper are important for the basic understanding of the 3d and 4d Tm doping effect ZnO and have a wide range of applications in designing high-efficiency energy harvesting solar cells.