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The purpose of this paper is to forecast the reliable storage life of a certain kind of equipment under the normal stress level.

Through the stepping stress acceleration life test and the failure mechanism analysis, this paper aims to confirm the stress level for the stepping stress acceleration life test of a certain kind of equipment and establish the data processing mathematical model and storage life forecasting method.

The stress level for the stepping stress acceleration life test of a certain kind of equipment is confirmed and the data processing mathematical model and storage life forecasting method is established.

Availability of data is the main limitation affecting which model will be applied.

Useful advice for products' storage life forecasting.

The paper presents a new approach to product storage life estimation.

The purpose of this paper is to put forward a method which uses a computer to make a large number of simulated tests and determine the reference value of a system reliability index according to a unit reliability index.

At the beginning of conducting an index demonstration and development on a new system, its unit reliability index can already reflect the unit reliability level accurately. Based on this characteristic, this index is used as the confidence lower limit of single side estimated in the unit reliability interval to find the failure distribution law of the unit. On this basis, a great number of simulated tests are made by a computer to calculate the unit failure number and reliability point estimated value every test.

The confidence lower limit of single side estimated in the system reliability interval is found by counting up the simulated test data of these units.

Availability of data is the main limitation regarding which model will be applied.

A useful advice for system reliability analysis and calculation.

This paper presents a new approach of system reliability analysis.

This paper aims to identify data set entities in scientific literature. To address poor recognition caused by a lack of training corpora in existing studies, a distant supervised learning-based approach is proposed to identify data set entities automatically from large-scale scientific literature in an open domain.

Firstly, the authors use a dictionary combined with a bootstrapping strategy to create a labelled corpus to apply supervised learning. Secondly, a bidirectional encoder representation from transformers (BERT)-based neural model was applied to identify data set entities in the scientific literature automatically. Finally, two data augmentation techniques, entity replacement and entity masking, were introduced to enhance the model generalisability and improve the recognition of data set entities.

In the absence of training data, the proposed method can effectively identify data set entities in large-scale scientific papers. The BERT-based vectorised representation and data augmentation techniques enable significant improvements in the generality and robustness of named entity recognition models, especially in long-tailed data set entity recognition.

This paper provides a practical research method for automatically recognising data set entities in scientific literature. To the best of the authors’ knowledge, this is the first attempt to apply distant learning to the study of data set entity recognition. The authors introduce a robust vectorised representation and two data augmentation strategies (entity replacement and entity masking) to address the problem inherent in distant supervised learning methods, which the existing research has mostly ignored. The experimental results demonstrate that our approach effectively improves the recognition of data set entities, especially long-tailed data set entities.

The purpose of this paper is to examine how Si-shu, a traditional form of local, private education grounded in classical instruction, responded to the rapid modernization of education during the late Qing dynasty and early Republic of China and to explain why these schools, once extraordinarily adaptable, finally disappeared.

The authors have examined both primary and secondary sources, including government reports, education yearbooks, professional annals, public archives, and published research to analyze the social, political and institutional changes that reshaped Si-shu in the context of China's late-19th- and early-20th-century educational modernization.

Si-shu went through four stages of institutional change during the last century. First, they faced increased competition from new-style (westernized) schools during the late Qing dynasty. Second, they engaged in a process of intense self-reform, particularly after the Xinhai Revolution of 1911. Third, they were marginalized by the new educational systems of the Republic of China, especially the Renxu School System of 1922 and the Wuchen School System of 1928. Finally, after the foundation of the People's Republic of China in 1949, they were considered remnants of feudal culture and forcibly replaced by modern schools.

This paper brings hitherto unexplored Chinese sources to an English-speaking audience in an effort to shed new light on the history of traditional Chinese education. The fate of Si-shu was part of the larger modernization of Chinese education – a development that had both advantages and disadvantages.

The purpose of this paper is to examine team external learning, particularly focusing on: how leader external learning behavior affects team external learning; how team external learning influences employee creativity; and whether team internal learning is a moderator between the cross‐level relationship of external learning and employee creativity in Chinese R&D teams.

Survey questionnaire were administered to a sample of 80 R&D teams comprising 331 employees from three medium‐sized Chinese high‐tech companies. HLM was used to test cross‐level relationships.

The paper hypothesizes that: leader external learning positively influences team external learning; team external learning leads to employee creativity; and team internal learning moderates the relationship between team external learning and employee creativity. Results support hypotheses 2 and 3, but not hypothesis 1. In addition, leader external learning is found to positively influence employee creativity.

This study has implications for both team leaders and top management. Although the context of this study is in Chinese R&D teams, all those teams facing similar environment to R&D teams can also learn from this study. There are several interesting implications for scholars who are studying teams, creativity and innovation.

Combining fields of team learning, boundary spanning, creativity and leadership, the paper addresses the following four questions, and provides further insights to the area of team external learning: First, what is the cross level relationship between team external learning and employee creativity? Second, is internal learning a moderator on the relationship between team external learning and employee creativity in R&D project teams? Third, is leader external learning behavior one of antecedents of team external learning? Fourth, is there anything unique about team external learning in Chinese culture? The paper provides research evidence for each of these questions.

The purpose of this paper is to propose a DC-port voltage balance strategy realizing it by logic combination modulation (LCM). This voltage balance strategy is brief and high efficient, which can be used in many power electronic devices adopting the cascaded H-bridge rectifier (CHBR) such as power electronic transformer (PET).

The CHBR is typically as a core component in the power electronic devices to implement the voltage or current conversion. The modulation method presented here is aiming to solve the voltage imbalance problem occurred in the CHBR with more stable work station and higher reliability in ordinary operating conditions. In particular, by changing the switch states smoothly and quickly, the DC-port voltage can be controlled as the ideal value even one of the modules in CHBR is facing the load-removed problem.

By using the voltage balance strategy of LCM, the problem of voltage imbalance occurring in three-phase cascaded rectifiers has been solved properly. With the lower modulation depth, the efficiency of the strategy is shown to be better and stronger. The strategy can work reliably and quickly no matter facing the problem as load-removed change or the ordinary operating conditions.

The limitation of the proposed DC-port voltage balance strategy is calculated and proved, in a three-module CHBR, the LCM could balance the DC-port voltage while one module facing the load-removed situation under 0.83 modulation depth.

This paper provides a useful and particular voltage balance strategy which can be used in the topology of three-phase cascaded rectifier. The value of the strategy is that a brief and reliable voltage balance method in the power electronic devices can be achieved. What is more, facing the problem, such as load-removed, in outport, the strategy can response quickly with no switch jump and switch frequency rising.

Electrical impedance tomography (EIT) is a technique for reconstructing the conductivity distribution by injecting currents at the boundary of a subject and measuring the resulting changes in voltage. Image reconstruction for EIT is a nonlinear problem. A generalized inverse operator is usually ill-posed and ill-conditioned. Therefore, the solutions for EIT are not unique and highly sensitive to the measurement noise.

This paper develops a novel image reconstruction algorithm for EIT based on patch-based sparse representation. The sparsifying dictionary optimization and image reconstruction are performed alternately. Two patch-based sparsity, namely, square-patch sparsity and column-patch sparsity, are discussed and compared with the global sparsity.

Both simulation and experimental results indicate that the patch based sparsity method can improve the quality of image reconstruction and tolerate a relatively high level of noise in the measured voltages.

EIT image is reconstructed based on patch-based sparse representation. Square-patch sparsity and column-patch sparsity are proposed and compared. Sparse dictionary optimization and image reconstruction are performed alternately. The new method tolerates a relatively high level of noise in measured voltages.

The purpose of this paper is to use the corresponding magnetic sensor and detection method to detect and image the defects of small diameter pipelines. Urban gas pipeline is an energy transportation tool for urban industrial production and social life, which is closely related to urban safety. Preventing the occurrence of urban gas pipeline transportation accidents and carrying out pipeline defect detection are of great significance for the urban economic and social stability. To perform pipeline defect detection, the magnetic flux leakage internal detection method is generally used in the detection of large-diameter long-distance oil and gas pipelines. However, in terms of the internal detection of small-diameter pipelines, due to the heavy weight, large structure of the detection device and small pipe diameter, the detection is more difficult.

In order to solve the above matters, self-made three-dimensional magnetic sensor and three-dimensional magnetic flux leakage imaging direct method are proposed for studying the defect identification. Firstly, for adapting to the diameter range of small-diameter pipelines, and containing the complete information of the defect, a self-made three-dimensional magnetic sensor is made in this paper to improve the accuracy of magnetic flux leakage detection. And on the basis of it, a small diameter pipeline defect detection system is built. Secondly, as detection signal may be affected by background magnetic field interference and the jitter interference, the complete ensemble empirical mode decomposition with adaptive noise method is utilized to screen the detected signal. As a result, the useful signal is reconstructed and the interference signal is removed. Finally, the defect contour inversion imaging of detection is realized based on the direct method of three-dimensional magnetic flux leakage imaging, which includes three-dimensional magnetic flux leakage detection data and data segmentation recognition.

The three-dimensional magnetic flux leakage imaging experimental results shown that, compared to the actual defects, the typical defects, irregular defects and crack groove defects can be analyzed by the magnetic flux leakage defect contour imaging method in qualitative and quantitative way respectively, which provides a new idea for the research of defect recognition.

A three-dimensional magnetic sensor is made to adapt the diameter range of small diameter pipeline, and based on it, a small-diameter pipeline defect detection system is built to collect and display the magnetic flux leakage signal.

An industrialized building system (IBS) is regarded as an effective residential building system that provides several benefits, including high quality, low cost, short time, good flexibility, reduced waste, and strong environmental performance. This system is considered to be valuable in promoting sustainable practices in China, where plans for urbanization have been established. However, the adoption of IBS in China is extremely limited. Potential risks exist and affect the attitudes of practitioners toward the use of this system. The purpose of this paper is to prioritize and analyze these risks and to develop corresponding strategies for mitigating these risks in China.

In total, 24 risks that inhibit the implementation of IBS in China are identified through literature review and examined through interviews for consistency. A questionnaire survey is conducted to quantify the significance of these risks. Cronbach’s coefficient α is employed to measure the internal consistency among the risk factors. The survey results are further analyzed using three case studies.

The top five risks identified are “poor cooperation between multi-interface,” “inappropriate design codes and standards for industrialized buildings,” “lack of management practices and experiences,” “enormous difficulty in achieving return on high initial investment,” and “lack of a quality monitoring mechanism for the production process.” The findings emphasize the government’s leading role in promoting the new building system in its introduction and enforcement of adequate policies and regulations. Practitioners are also instrumental in establishing proper understanding and knowledge of IBS and its application.

This study bridges the knowledge gaps on risk identification for implementing IBS in China. The findings provide practitioners and decision makers with valuable references for adopting adequate risk management methods and policies to promote IBS in China.

This study aims to investigate the effects of peers on corporate payout policies in one of the largest emerging markets – India. It also examines the motives for mimicking payout decisions.

The sample is composed of 3,024 non-financial and non-government firms listed on the National Stock Exchange (NSE) and Bombay Stock Exchange (BSE) for the period 1995 to 2020. To encounter the endogeneity problem, the instrumental variable technique based on peer firms' idiosyncratic risk is used to estimate the effects of peers on firms' payout policy. To define peer reference groups, the authors use the basic industry classification of the firms.

The results indicate a significant positive impact of peers on firms' dividend policies in India. A firm with all dividend-paying peers is more likely to declare dividends than the one with no dividend-paying peers. Further, peer effects are found to be more pronounced amongst larger and older firms, thus supporting the rivalry theory of mimicking.

To the best of the authors' knowledge, the present study is the first of its kind that attempts to understand peer effects on payout decisions in an emerging market India, that offers a unique institutional setting. Moreover, the authors extend the existing literature by investigating the peer effects on a firm's payout policies considering various firm-level characteristics, such as growth opportunity, cash holding, financial constraint and profitability, which previous studies have not taken into consideration. These results provide additional insights into the heterogeneity and motives behind peer effects.