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The purpose of this paper is to propose a time‐dependent mobility degradation model which is independent from the process or operating conditions.

In total, four transistors under test are electrically stressed using constant positive electrical stress voltage technique with the gate bias of V_G=40 V DC, where the source and drain were grounded. The authors increased the stress voltage step by step to avoid electrostatic discharge and recorded the I_D‐V_DS and I_D‐V_GS measurements in time intervals during the stress.

The experimental results show that the output current and the threshold voltage of the transistor are increased after the stress. Mobility and channel length are decreased. The changes in the transistor parameters were associated to interface state Si/SiO₂ effects. The authors used the physical changes in transistor and proposed a new‐time dependent mobility degradation model. The mobility change was calculated using the proposed model and compared with the experimental results. It was seen that the calculated and experimental results are in good agreement.

This is an original research paper and enables the mobility degradation to be predicted independently from effects of process or operational changes such as oxide thickness, substrate doping, and applied voltages on transistor.

As the physical dimensions of the devices are reduced to the submicrometer regime, the hot‐carrier reliability has become an important issue in the scaling of the p‐MOSFET as well as the n‐MOSFET. In this paper, we present a unified approach for p‐MOSFET degradation due to the trapping of the hot electrons in the gate oxide layers. A physical analytical model, based on the pseudo two‐dimensional model, is derived for the first time to describe the linear and saturation drain current degradation. The model has been verified by comparing the calculation and the measurement from submicron p‐MOSFET's with different channel lengths and oxide thickness. There are no empirical parameters in the model. Two physical parameters: the capture cross section and the density of states of electron traps, which can be determined independently from the measured degradation characteristics, are valid for both the linear current and the saturation current degradation. The simple expression is very suitable for the predicting of the circuit reliability.

The effect of stress induced defects on the ohmic region characteristics of short channel MOSFETs is analyzed by means of a two dimensional device simulator. The device aging is summarized in the formation of a narrow defective interface region whose nature, length and position above the channel are the parameters of our investigation. The channel conductance and transconductance degradations were found to be greatly influenced by the position of the defective region and its length. Also, fundamental differences were observed between the effects of interface states and fixed oxide charges. The interaction between the defective and defect‐free channel regions was found to produce a transconductance overshoot which attenuates the aging effects. Finally, a parameter extraction method based on a two‐piece analytical model of locally damaged MOSFETs is elaborated and validated by means of a 2‐D simulation.

The electromigration degradation model of nonlinear electrical properties of non‐uniform structures with intercrystallite potential barriers is developed. It allows connecting the increasing of near surfaces concentration of volume donors by their migration in electrical field at heating up structures by means of electrical current in the process of degradation. It results in experimentally observed deterioration varistoral properties, deterioration and asymmetrical deformation of currentvoltage characteristics during their exploitation.

The purpose of this paper is to investigate the temperature reliability for a parallel high-efficiency class-E power amplifier (PA).

To explore the relationship between temperature and direct current (DC) characteristics, output power, S parameters and efficiency of the PA quantitatively, a series of reliability experiments have been designed and conducted to study the temperature reliability for this PA.

From the results, the prominent performance degradation even failure is found during the testing. Furthermore, the thermal shock test can cause permanent failure, which is a great threat for PA.

Therefore, to ensure the good performance, the influence of temperature on PA reliability should be carefully considered during the stage of PA design.

All these can provide important guidance for the reliability design of PA.

All these can give some important guidance for PA application.

In addition, PA is usually designed according to the electrical properties at the room temperature. From the results above, it can be concluded that it may be unable to satisfy the performance requirement at high temperature. In turn, if it is designed according to the electrical properties at low temperature, the transistor often works in the super-saturated state, the reliability of PA will become the new problem. Therefore, to ensure the good performance, the influence of temperature on PA reliability should be carefully considered during the design.

This paper aims to define a proposal of a theoretical–methodological framework aimed at supporting researchers in conducting studies on the topic of environmental mobility.

The complexity of environmental change and the frequent subsequent human mobility raises challenges in the research process. The variety of theoretical and methodological approaches that can be applied to each of the phenomena contributes to different layers of analysis when focusing on the decision-making process of migration due to environmental factors. Drawing from the theoretical and methodological frameworks used by scholars, this paper includes an analysis of how they are applied in empirical studies that focus on environmental change and mobility in the Middle East and North Africa (MENA) region.

Empirical studies in this field for the MENA region are focused on collecting and analyzing data but are not linking it with wider human mobility theoretical and methodological frameworks. The proposal included in this study privileges the use of a qualitative methodology, aimed at obtaining an overview of the individuals’ experience.

This study adds to existing overviews of empirical studies of environmentally induced mobility by analyzing in detail the dimensions used to frame the methodological and theoretical research approaches in the empirical studies used in different disciplines that study the environment and/or human mobility. The studies analyzed focus on the different countries in the MENA region, which has the highest level of forced migratory movements in the world while facing challenges in terms of environmental degradation.

The purpose of this study is to regard winter heating as a quasi-natural experiment to identify the possible causal effects of winter heating on population mobility. However, there are scant research studies examining the effect of atmospheric quality on population mobility. There also exists some relevant research studies on the relationship between population mobility and environmental degradation (Lu et al., 2018; Reis et al., 2018; Shen et al., 2018), and these studies exist still some deficiencies.

The notorious atmospheric quality problems caused by coal-fired heating in winter of northern China have an aroused widespread concern. However, the quantitative study on the effects on population mobility of winter heating is still rare. In this study, the authors regard the winter heating as a quasi-natural experiment, based on the of daily panel data of 58 cities of Tencent location Big Data in China from August 13 to December 30 in 2016 and August 16 to December 30 in 2017, and examine the impacts of winter heating on population mobility by utilizing a regression discontinuity method.

The findings are as follows, in general, winter heating significantly aggravates regional population mobility, but the impacts on population mobility among different cities are heterogeneous. Specifically, the effects of winter heating on population mobility is greater for cities with relatively good air quality, and the effects is also more obvious for big and medium-sized cities than that in small cities. In addition, different robustness tests, including continuity test, different bandwidth tests and alternative empirical model, are adopted to ensure the reliability of the conclusion. Finally, the authors put forward corresponding policy suggestions from the three dimensions of government, enterprises and residents.

First, regarding winter heating as a quasi-natural experiment, a regression discontinuity design method is introduced to investigate the relationship between winter heating and population mobility, which is helpful to avoid the estimation error caused by endogeneity. Second, the authors use the passenger travel “big data” based on the website of Tencent Location Big Data, which can effectively capture the daily characteristics of China's population mobility. Third, this study discusses the population mobility from the perspective of winter heating and researches population mobility before and after winter heating, which is helpful in enriching the research on population mobility.

Modifications of physical and electrical properties of the vertical double‐diffused metal oxide semiconductor (VDMOS) transistor are observed on using the device under some conditions of “functional” stress. This paper presents the characterization and the 2D simulation for the pre‐ and post‐stressed device, to point out the degraded parameters due to the functional stress, and to analyze their effects on the degradation of the VDMOS static and dynamic characteristics.

The purpose of this paper is to study the impact of high‐power microwave interferences on electronic devices needs the simulation of semiconductor components. Although the semiconductor equations can be solved numerically by Newton method, the conventional Newton method exhibits significant speed degradation when the power of interference is high enough to cause device burnout. Therefore, this paper aims at speeding up the simulation of the semiconductor components under high‐power microwave interferences.

Some approximations in conventional Newton method works efficiently only when the electric field in the simulated semiconductor is relatively low. This is the reason of the formerly mentioned speed degradation problem. The proposed method speeds up the simulation by modifying these approximations to acquire enough precision in these high‐power situations.

The modified Newton method proposed in this paper shows an acceleration of 100‐150 percent compared to conventional method for typical applications. Moreover, the simulation speed becomes nearly independent of the power of the microwave interferences, which means the speed degradation phenomenon of the conventional method has almost been eliminated.

This paper proposes a modified Newton method to speed up the simulation of the semiconductor components under high‐power microwave interferences.

Contemporary literature reveals that, to date, the poultry livestock sector has not received sufficient research attention. This particular industry suffers from unstructured supply chain practices, lack of awareness of the implications of the sustainability concept and failure to recycle poultry wastes. The current research thus attempts to develop an integrated supply chain model in the context of poultry industry in Bangladesh. The study considers both sustainability and supply chain issues in order to incorporate them in the poultry supply chain. By placing the forward and reverse supply chains in a single framework, existing problems can be resolved to gain economic, social and environmental benefits, which will be more sustainable than the present practices.

The theoretical underpinning of this research is ‘sustainability’ and the ‘supply chain processes’ in order to examine possible improvements in the poultry production process along with waste management. The research adopts the positivist paradigm and ‘design science’ methods with the support of system dynamics (SD) and the case study methods. Initially, a mental model is developed followed by the causal loop diagram based on in-depth interviews, focus group discussions and observation techniques. The causal model helps to understand the linkages between the associated variables for each issue. Finally, the causal loop diagram is transformed into a stock and flow (quantitative) model, which is a prerequisite for SD-based simulation modelling. A decision support system (DSS) is then developed to analyse the complex decision-making process along the supply chains.

The findings reveal that integration of the supply chain can bring economic, social and environmental sustainability along with a structured production process. It is also observed that the poultry industry can apply the model outcomes in the real-life practices with minor adjustments. This present research has both theoretical and practical implications. The proposed model’s unique characteristics in mitigating the existing problems are supported by the sustainability and supply chain theories. As for practical implications, the poultry industry in Bangladesh can follow the proposed supply chain structure (as par the research model) and test various policies via simulation prior to its application. Positive outcomes of the simulation study may provide enough confidence to implement the desired changes within the industry and their supply chain networks.