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Measurement-while-drilling (MWD) system has been used to provide trajectory and inclination parameters of the oil and gas well. Fluxgate magnetometer is a traditional choice for one MWD system; however, it cannot obtain effective trajectory parameters in nonmagnetic environments. Fiber-optic-gyroscope (FOG) inclinometer system is a favorable substitute of fluxgate magnetometer, which can avoid the flaws associated with magnetic monitoring devices. However, there are some limitations and increasing surveying errors in this system under high impact conditions. This paper aims to overcome these imperfections of the FOG inclinometer system.

To overcome the imperfections, filtering algorithms are used to improve the precision of the equipment. The authors compare the low-pass filtering algorithm with the wavelet de-noising algorithm applied to real experimental data. Quantitative comparison of the error between the true and processed signal revealed that the wavelet de-noising method outperformed the low-pass filtering method. To achieve optimal positioning effects, the wavelet de-noising algorithm is finally used to inhibit the interference caused by the impact.

The experimental results show that the method proposed can ensure the azimuth accuracy lower than ±2 degrees and the inclination accuracy lower than ± 0.15 degrees under the condition of interval impact. The method proposed can overcome the interference generated by the impact in the well, which makes the instrument suitable for the measurement of small-diameter casing well.

After conducting the wavelet threshold filtering on the raw data of accelerometers, the noise generated by the impact is successfully suppressed, which is expected to meet the special requirement of the down-hole survey environment.

This paper aims to investigate the moisture diffusion behavior in a system-in-package module systematically by moisture-thermalmechanical-coupled finite element modeling with different structure parameters under increasingly harsh environment.

A finite element model for a system-in-package module was built with moisture-thermal-mechanical-coupled effects to study the subsequences of hygrothermal conditions.

It was found in this paper that the moisture diffusion path was mainly dominated by hygrothermal conditions, though structure parameters can affect the moisture distribution. At lower temperatures (30°C~85°C), the direction of moisture diffusion was from the periphery to the center of the module, which was commonly found in simulations and literatures. However, at relatively higher temperatures (125°C~220°C), the diffusion was from printed circuit board (PCB) to EMC due to the concentration gradient from PCB to EMC across the EMC/PCB interface. It was also found that there exists a critical thickness for EMC and PCB during the moisture diffusion. When the thickness of EMC or PCB increased to a certain value, the diffusion of moisture reached a stable state, and the concentration on the die surface in the packaging module hardly changed. A quantified correlation between the moisture diffusion coefficient and the critical thickness was then proposed for structure parameter optimization in the design of system-in-package module.

The different moisture diffusion behaviors at low and high temperatures have seldom been reported before. This work can facilitate the understanding of moisture diffusion within a package and offer some methods about minimizing its effect by design optimization.

With the analysis of the causes of corruption, this study aims to investigate specific anti-corruption measures that can be implemented to reform the political system and the social climate of China.

This study examines 97 severe corruption cases of high-ranking officials in China, which occurred between 2012 and 2015. As this insinuates that both institutional and social corruption are major problems in China, the analysis delves into multiple facts of corruption, including different types, four primary underlying causes, and suggestions regarding the implementation of three significant governmental shifts that focus on investigation, prevention tactics and legal regulations.

China’s corruption is not only individual-based but also it has developed into institutional corruption and social corruption. Besides human nature and instinct, the causes of corruption can be organised into four categories, namely, social customs, social transitions, institutional designs and institutional operations. For the removed high-ranking officials, the formation of interest chains was an important underlying cause behind their corruption.

This study makes a significant contribution to the literature because this study provides a well-rounded approach to a complex issue by highlighting the significance of democracy and the rule of law as ways to regulate human behaviour to combat future corruption.

Pervasive computing environment allows the users to access the services anywhere and anytime. Due to the dynamicity, mobility, security, heterogeneity, and openness have become a major challenging task in the Pervasive computing environment. To solve the security issues and to increase the communication reliability, an authentication-based access control approach is developed in this research to ensure the level of security in the Pervasive computing environment.

This paper aims to propose authentication-based access control approach performs the authentication mechanism using the hashing, encryption, and decryption function. The proposed approach effectively achieves the conditional traceability of user credentials to enhance security. Moreover, the performance of the proposed authentication-based access control approach is estimated using the experimental analysis, and performance improvement is proved using the evaluation metrics. It inherent the tradeoff between authentication and access control in the Pervasive computing environment. Here, the service provider requires authorization and authentication for the provision of service, whereas the end-users require unlinkability and untraceability for data transactions.

The proposed authentication-based access control obtained 0.76, 22.836 GB, and 3.35 sec for detection rate, memory, and time by considering password attack, and 22.772GB and 4.51 sec for memory and time by considering without attack scenario.

The communication between the user and the service provider is progressed using the user public key in such a way that the private key of the user can be generated through the encryption function.

The purpose of this paper is to summarize the advances in grey system theory research and various application achievements in science and engineering. At the same time, it commemorates the 40th anniversary of the birth of grey system theory and the 10th anniversary of Grey Systems–Theory and Application.

Firstly, the innovations of theoretical research in grey system theory were summarized and some of the widely recognized new results are briefly described. By searching and combing the research results of grey system theory in China national knowledge infrastructure (CNKI) database and Web of Science by Institute for Scientific Information (ISI), this paper shows the rapid development trend of grey system theory in the past 40 years, and the successful applications of grey system theory in the fields of social sciences, natural sciences and engineering technologies.

More than 227 thousands literature were found by input 10 phrases such as grey system, grey number and sequence operator etc. in CNKI database. After entering the new century, the number of grey system papers included in CNKI database is increasing rapidly. Since 2008, more than 10 thousands papers have been included per year and more than 15 thousands papers have been included per year since 2014. Grey system method and model are widely used in physics, chemistry, biology and other fields of natural science, as well as transportation, electric power, machinery and other fields of engineering technology, and a large number of valuable results have been achieved.

It can be seen that the grey system theory plays an important role in promoting China’s scientific and technological progress, innovation and development and high-level talent training from tens of thousands of literatures marked with important national science and technology projects and a large number of grey system literatures published by China’s double first-class universities and double first-class discipline construction universities.

Both innovations of theoretical research and practical application play important role in the growth of new theory. The innovations of theoretical research provide methods and tools for practical application, which is conducive to improve application efficiency and broaden application fields. A large number of practical applications needs have become the source of theoretical innovation and the solid background for the birth of theoretical innovation achievements.

A successful process of design concept evaluation has positive influence on subsequent processes. This study aims to consider the evaluation information at multiple stages and the interaction among evaluators and improve the credibility of evaluation results.

This paper proposes a multi-stage approach for design concept evaluation based on complex network and bounded confidence. First, a network is constructed according to the evaluation data. Depending on the consensus degree of evaluation opinions, the number of evaluation rounds is determined. Then, bounded confidence rules are applied for the modification of preference information. Last, a planning function is constructed to calculate the weight of each stage and aggregate information at multiple evaluation stages.

The results indicate that the opinions of the evaluators tend to be consistent after multiple stages of interactive adjustment, and the ordering of design concept alternatives tends to be stable with the progress of the evaluation.

Updating preferences according to the bounded confidence rules, only the opinions within the trust threshold are considered. The attribute information of the node itself is inadequately considered.

This method addresses the need for considering the evaluation information at each stage and minimizes the impact of disagreements within the evaluation group on the evaluation results.

China's agricultural production trusteeship is characterized by the organic link between household operation of small-scale peasant economy and agricultural socialized services, which releases agricultural development vitality and promotes agricultural modernization. As one of the agricultural production trusteeship modes, the whole process trusteeship is suitable for the actual situation of China's aging population and labor force transfer. This paper aims to construct an evolutionary game model containing multistakeholder to explore the behavior decisions through numerical simulation and to provide useful suggestions for the formation of a positive and stable trusteeship relationship and the sound development of the whole process trusteeship of agricultural production.

The paper incorporates village committees, service organizations and farmers into the same research framework, selects “guarantee + dividends” as the income distribution method and applies the evolutionary game method to analyze behavioral choices and evolutionary paths of stakeholders. By constructing the expectation function, establishing the replicator dynamic equations and analyzing the tripartite evolutionary stability strategy, the authors explore the factors that affect the stakeholders’ strategy choice and determine asymptotically stable points and stability conditions.

(1) There is a game relationship among village committees, farmers and service organizations in the whole process trusteeship of agricultural production, asymptotically stable points (0,0,1) and (1,1,1) are obtained through calculation. (2) The proportion of stakeholders' strategy choice, the weight of the whole process trusteeship of agricultural production in the performance appraisal of the village committee, the village committee's supervision cost, the village committee's reputation effect and the penalty for false dividends of the service organization will affect the speed at which the curve representing the tripartite relationship approaches two asymptotically stable points.

The countermeasures proposed in the paper have excellent reference value. (1) For areas that have realized the project: Village committees can solve the trusteeship problems exposed in the initial areas and improve farmers' satisfaction with the project. (2) For areas that have not realized the project: Those regions will receive more experience references and enhance their confidence in this project. The limitation of the paper is that it takes the main grain-producing areas in only the three northeastern provinces of China as the research object. The next research object will be extended to the whole country.

This paper propose strategies for realizing the orderly operation of the whole process trusteeship of agricultural production: first, increase the proportion of stakeholders' strategy choices; second, reduce the village committee's supervision cost; third, increase the weight of the whole process trusteeship of agricultural production in the performance appraisal of the village committee; fourth, improve the village committee's reputation effect; fifth, increase the penalty for false dividends of the service organization.

Agricultural production trusteeship is in its initial stage in China. The interest relationships between stakeholders are not yet clear. The paper innovatively applies the evolutionary game method to the research field of the whole process trusteeship of agricultural production. According to conditions in China, based on ensuring the guaranteed income, the paper introduces the dividend income variable and establishes a tripartite game model of village committees, service organization and farmers. The paper provides suggestions for the orderly and healthy development of China's agricultural production trusteeship and provides experience for the operation of other modes of agricultural production trusteeship.

The purpose of this paper is to develop and validate a scale measurement of supply chain operations reference (SCOR)-related performance indicators and proposed constructs, SCOR-related performance indicators as practices within the Indian manufacturing sector.

A literature-based model on SCOR processes with five constructs and respective performance indicators was empirically validated by using a structured questionnaire. A total of 155 respondents among Indian manufacturing sector participated in this research, and the returned questionnaires were analyzed by using structural equation modeling.

The study established a relationship among the SCOR-related performance indicators and overall supply chain performance indicators (OSCPI). The moderation effect of demographic characteristics, namely, employee size, company age and type of company showed significant differences between SCOR-related performance indicators and overall supply chain indicators.

The scope of the study is limited to specific Indian manufacturing firms. The survey could not represent whole population of manufacturing sector.

The findings assist managers/supply chain practitioners in improving the performance measures identified using the standard framework, i.e., SCOR processes, overall supply chain performance measures as standard practices for Indian manufacturing sector for a profitable and sustainable business growth in global environment.

This research holds a value for suggested practices under SCOR processes and the proposed model for OSCPI, a path finder/performance measurement tool for supply chain professionals in the Indian context.

This paper traces the incorporation of western educational histories in the development of normal-school curricula during the late Qing Dynasty and the Republic of China (1901–1944). It uses publication networks to show how the study of comparative educational history facilitated the international circulation of knowledge in the teaching profession, and how the “uses” of educational history were shaped by larger geopolitical forces.

This paper analyzes the international exchange of texts between normal schools in China and Japan and, subsequently, between normal schools in China and the United States. A database of 107 publications in the field of western educational history that were adopted in China reveals specific patterns of textual citation, cross-reference, and canon-formation in the field of educational historiography.

With conclusions derived from a combination of social network analysis and clustering analysis, this paper identifies three broad stages in China's development of normal-school curricula in comparative educational history: “Japan as Teacher,” “transitional period” and “America as Teacher.”

Statistical analysis can reveal citation and reference patterns but not readers' understanding of the deeper meaning of texts – in this case, textbooks on the subject of western educational history. In addition, the types of publications analyzed in this study are relatively limited, the articles on the history of education in journals have not become the main objects of this study.

This paper uses both quantitative and qualitative methods to uncover the transnational circulation of knowledge in the field of comparative educational history during its formative period in China.