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As the global economy continues to boom, there remains a significant need for more efficient transportation and effective management in corporate logistics. In this regard, railways have been considered one of the most efficient modes for long distance transportation. In Asia, there are several extensive and direct railroads such as the TSR (Trans-Siberian-Railroad), the TCR (Trans-Chinese-Railroad) and the TMR (Trans-Mongolian-Railroad) which could connect Asia to Europe. If these railroad networks such as the TKR (Trans-Korean-Railroad) were fully operational, it is expected that they would replace a major portion of the current global trade transportation with is sent through other shipping methods. Therefore, the development of railroad networks is one of the most important steps toward an integrated international transportation system. However, in reality, it is difficult to achieve this vision because of the political and economic problems surrounding multiple countries that this network must cut across. Moreover, it is difficult to ensure the railways’ economic competitiveness when it is compared with other logistics options. In this study, we aim to discover the status quo about railway networks by focusing on the TCR and TSR. Through in-depth interviews and surveys with actual users of these networks, current issues and problems are analysed in order to make suggestions for improvements. This research also provides meaningful insights which the TKR-TSR and TKR-TCR railway networks should consider if they want to continue to be successful in the future.

The purpose of this paper is to investigate the non-linear association between trade credit and profitability of small and medium-sized enterprises (SMEs). Moreover, this paper analyses whether the above relationship varies according to financial constraints of SMEs.

The authors use panel data methodology to conduct investigations for a sample of 1,509 non-financial listed SMEs from nine countries or territories located in the East Asia and Pacific region, namely, China, Vietnam, Malaysia, Thailand, Japan, South Korea, Taiwan, Singapore and Hong Kong, over the period from 2010 to 2016.

This study indicates that trade credit receivable (TCR) and trade credit payable (TCP) have an inverted U-shaped relationship with SMEs’ profitability, which implies the existence of an optimal trade credit level that balances between costs and benefits to maximize their profitability. This result suggests that managers should try to keep the level of trade credit investment as close to the optimal point as possible to avoid the case that their profitability reduces when they move away from this point. Moreover, this study also finds that the optimal trade credit level is sensitive to the financial constraints of SMEs. In particular, optimal level of more financially constrained firms is lower than that of less financially constrained firms.

A number of contributions that this study makes to the existing literature are presented as follows. First, the paper takes account of the possible presence of a concave relationship between trade credit and SMEs’ profitability, largely ignored by the existing empirical literature. Second, it demonstrates this association in terms of both aspects of trade credit, including TCR and TCP. Third, the study investigates the effect of the different level of financial constraints faced by SMEs on the relationship between trade credit and their profitability.

This paper aims to select parameters such as temperature thermal stability and temperature coefficient of resistance (TCR) for Ni–P resistive alloys obtained by electroless metallization. Ni–P alloys are used in the manufacture of precision resistors characterized by TCR in the range of ± 10 ppm/K. The correlation of the technological parameters with the electrical properties of resistors enables the accurate prediction of the TCR resistors.

The Ni–P layers were obtained by a continuous process at about 373 K in a solution with the acidity of pH = 2 and then dried for two hours at 393 K. Subsequently, the Ni–P layer was stabilized for two hours in the temperature range of 453-533 K. Resistance was measured with an accuracy of 1 mΩ. TCR was determined with an accuracy of 1 ppm/K in the temperature range 298-398 K. In the next stage of the investigation, the increase in TCR of the Ni–P alloy was correlated with the increase in stabilization temperature. Scanning electron microscope images of the alloy surface were studied to assess grain sizes and to relate the average grain size with TCR values of resistive alloys. The X-ray diffraction analysis was performed to determine the crystallization temperature of Ni–P alloy.

The conducted investigation showed that the TCR increase in alloy is a linear function of stabilization temperature in the temperature range in which transition from amorphous phase to crystalline phases did not occur. TCR increase in Ni–P alloy arises from the increase of average size of grains resulting in decrease of scattering of electrons on grain boundaries. The analysis of alloy composition in chosen fragments of surface shows inhomogeneity growing with decreasing analyzed surface dimensions which proves that, before the stabilization, the structural arrangement of alloy is inconsiderable.

The obtained results are the first attempt to relate the morphology of surface with TCR of alloy and demonstration of linear dependence between an increase in TCR of amorphic Ni–P alloy and stabilization temperature of resistive layer. Such correlations are not described in available literature.

The paper aims to present a research on the impact of the stabilization process of a thin metallic layer (Ni-P) produced on a ceramic surface (Al₂O₃) by means of electroless metallization on its electric parameters and structure. On the basis of the research conducted, the existence of a relationship between resistance (R) and the temperature coefficient of resistance (TCR) of the test structure with a Ni-P alloy-based layer and the temperature of stabilization was proposed.

Metallic Ni-P layers were deposited on sensitized and activated substrates. Metallization was conducted in an aqueous solution containing two primary ingredients: sodium hypophosphite and nickel chloride. The concentration of both ingredients was (50-70) g/dm³. The process lasted 60 min, and the metallization bath pH was kept at 2.1-2.2, whereas the temperature was maintained at 363 K. The thermal stabilization process was conducted in different temperatures between 453 and 623 K. After the technological processes, the resistance and TCR of the test structures were measured with a micro ohmmeter. The composition and the morphology of the resistive layer of the structures examined was also determined.

The dependence of the resistance on the temperature of the stabilization process for the temperature range 553 to 623 K was described using mathematical relationships. The TCR of test resistors at the same thermal stabilization temperature range was also described using a mathematical equation. The measurements show that the resistive layer contains 82.01 at.% of nickel (Ni) and 17.99 at.% of phosphorus (P).

The results associate a surface morphology Ni-P alloy with the resistance and TCR according to temperature stabilization. The paper presents mathematical relationships that have not been described in the literature available.

The purpose of this paper is to study the variation of the temperature coefficient of resistance (TCR) of polymer thick film resistors, namely, PVC‐graphite thick film resistors, with parameters such as volume fraction, grain size, and high voltage.

A model is proposed to explain the observed variations, which assumes that the texture of the thick film resistors consists of insulator granules coated with conducting particles.

The paper finds that the TCR of these materials is controlled mainly by the contact resistance fluctuations between the conducting particles and the number of contacts each particle has with it neighbours. The variation of TCR with high voltage has also been explained with the help of this model and it is attributed to the changes in contact area and the number of contacts.

The value of the paper is in showing that apparently the TCR of polymer thick film resistors can be controlled by the expansion properties of the insulating medium. The variation of TCR with high voltage is also due to change in number of contacts between the conducting particles. These types of material may find applications in thermal sensors or as temperature control elements.

In the manufacture of resistors with low TCR values it is found that difficulties start at TCR values of less than ±50 ppm/°C. This paper will show if ±50 ppm/°C is a realistic value for high volume production.

This paper aims to develop a method for evaluating the failure probability and global sensitivity of multiple failure modes based on convex-probability hybrid uncertainty.

The uncertainty information of the input variable is considered as convex-probability hybrid uncertainty. Moment-independent variable global sensitivity index based on the system failure probability is proposed to quantify the effect of the input variable on the system failure probability. Two-mode sensitivity indices are adopted to characterize the effect of each failure mode on the system failure probability. The method based on active learning Kriging (ALK) model with a truncated candidate regions (TCR) is adopted to evaluate the systems failure probability, as well as sensitivity index and this method is termed as ALK-TCR.

The results of five examples demonstrate the effectiveness of the sensitivity index and the efficiency of the ALK-TCR method in solving the problem of multiple failure modes based on the convex-probability hybrid uncertainty.

Convex-probability hybrid uncertainty is considered on system reliability analysis. Moment-independent variable sensitivity index based on the system failure probability is proposed. Mode sensitivity indices are extended to hybrid uncertain reliability model. An effective global sensitivity analysis approach is developed for the multiple failure modes based on convex-probability hybrid uncertainty.

Teachers’ organisational identification is crucial for the success of educational reform in the change process. This study investigates how and under what conditions authentic principal leadership contributes to teachers’ organisational identification.

Data collected from 7907 public high school teachers across Türkiye were analysed using bootstrapping method. This research tested a moderated mediation model of authentic principal leadership effects on teachers’ organisational identification by incorporating teacher academic optimism as a mediator, and teacher collective responsibility as a moderator.

Results revealed significant direct and indirect effects of authentic principal leadership on the teachers’ organisational identification via teacher academic optimism. Teacher collective responsibility significantly moderated the effects of authentic principal leadership on both teacher academic optimism and on teachers’ organisational identification. The positive effects of authentic principal leadership were strengthened when the collective responsibility was higher.

This study integrates authentic leadership theory with social identity theory, which provides a more theoretically accurate understanding of how authentic principal leadership influences teachers’ organisational identification.

New resistor compositions prepared by using special kinds of glass, CdO and ruthenium compound have been developed. The properties of resistors prepared from various compositions were tested in relation to peak firing temperature varying in the range from 760°C up to 850°C. In this way conditions were found for resistor preparation with constant, positive and relatively high TCR (2,500 ppm/°C) and high long‐term stability at 95% relative humidity at 40°C, and with various sheet resistivity (500 ohms/sq.?3,000 ohms/sq.). This system is typical in containing only small amounts of ruthenium compound ranging from 6 wt % to 12 wt %. The resistors can be used for temperature measurement as temperature sensors.

Termination resistances can affect the behaviour of thin‐film resistors. Depending on the dimensions of a resistor both the TCR and the long‐term stability will be affected, while the termination resistance forms part of the practical resistance value. This paper deals with the results of an investigation concerning the influence of termination resistances with respect to the behaviour of thin‐film resistors. Three thin‐fiim technologies were investigated. Values for the resistance, TCR and ageing drifts of both the bulk material and the terminations will be discussed. Some remarks on the structure of a termination will be mentioned.