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The purpose of this paper is to detect and control the liquid‐level of stereolithography apparatus precisely.

A brightness‐variable laser source is adopted to remove the computational error of divider and a closed‐loop circuit is set to measure the terminal voltage directly proportional to the output current of photosensitive devices. It employs a sinking‐block device to control the liquid‐level.

The precise calibration result of this detecting device indicates that the resolution of the liquid‐level detection can reach ±1.5 μm.

This sinking‐block style liquid‐level control device can allow for the liquid‐level wave reduced from ±45 to ±15 μm.

The purpose of this paper is to show how to precisely control the liquid resin coating thickness in stereolithography (SL).

A vacuum adsorption coating equipment and technology are developed to precisely control the liquid resin coating thickness in SL. Dual‐electrode device is used, so adsorption can be precisely controlled and the electrode polarization can be avoided.

It turns out that the apparatus can control coating thickness effectively, and thickness uniformity is increased remarkably, which induces the standard deviation thickness decrease from 0.00547 to 0.00243 mm, and efficiency of rapid prototyping production increase by 53 percent.

The paper demonstrates that the apparatus can control coating thickness effectively.

Balancing accuracy and efficiency is an important evaluation index of response surface method. The purpose of this paper is to propose an adaptive order response surface method (AORSM) based on univariate decomposition model (UDM).

First, the nonlinearity of the univariate function can be judged by evaluating the goodness of fit and the error of curve fit rationally. Second, combining UDM with the order analysis of separate component polynomial, an easy-to-implement AORSM is proposed. Finally, several examples involving mathematical functions and structural engineering problems are studied in detail.

With the proposed AORSM, the orders of component functions in the original response surface can be determined adaptively and the results of those cases in this paper indicate that the proposed method performs good accuracy, efficiency and robustness.

Because just the cases with single failure mode and single MPP are studied in this paper, the application in multi-failure mode and multi-MPP cases need to be investigated in the coming work.

The nonlinearity of the univariate in the response surface can be determined adaptively and the undetermined coefficients of each component function are obtained separately, which reduces the computation dramatically.

This paper examines China's historiography on foreign education since 1900, with an emphasis on the period since 1949. The understanding of “foreign education” in China during this period shifted rapidly from the Western-centered approach that had been introduced from Japanese during the late Qing dynasty and the Republic of China to the Soviet-centered approach that followed the founding of New China to a restoration of Western-centered approaches after the “opening” of the late 1970s and 1980s. The paper asks: how has the study of foreign educational history changed over time in the People's Republic of China, how has the broader discipline of history of education changed, and how have successive generations of historians of education conceived of their intellectual and political roles?

Grounded in archival documents and the published works of influential historians of education, this study notes the ways in which political regime change affected the construction and application of academic knowledge.

This study identifies four stages in the Chinese historiography on foreign education: a formative stage (from 1900 until the late 1940s); a difficult post-revolutionary recovery, followed by growth and then suppression (from 1949 until the mid-1970s); a period of achievement combined with an academic crisis (from 1978 until the early 2000s); and finally, a recent transition marked by theoretical innovation and global integration (from the 2000s until the present).

This study finds that a narrow focus on “practical utility” or service to politics and policy has perturbed historians of foreign education in China and stunted their field's development. A look back at early periods in the historiography offers a warning about the potential dangers of extreme ideological/political utilitarianism. These dangers existed not only in the history of foreign education but also in the history of education research more broadly. A close examination of these dangers can help twenty-first-century historians of education in China balance the practical, political and professional dimensions of their research. To grasp the meaning of foreign education, historical research needs to be politically independent.

Interorganizational reciprocity plays a key role in relationships among software firms and open source communities. This study seeks to illuminate how a firm's open source strategy, characterized by its participation in the open source community, contributes to its financial performance.

Based on the norm of reciprocity and social capital theory, the study proposes a model comprising the behavioral antecedents and business results of a firm's symbiotic relationship with the open source community. Data were collected through a survey. Partial least squares-based structural equation modeling (PLS-SEM) was used to assess the results.

A firm's participative behaviors can have three dimensions: technology giving, technology taking and social participation. Technology taking directly impacts financial performance, whereas the effects of technology giving and social participation on financial performance are fully mediated by the firm's symbiotic relationship with the open source community.

Managers can understand how a specific behavior ultimately contributes to a symbiotic relationship or a firm's financial performance and how to flexibly align participation strategies with the business orientation.

The study adds to the open source literature by refining and enriching the conceptual domain of a firm's participative behaviors in open source communities. It also reveals how contrasting behavioral strategies impact a firm's financial performance.

“Sleeping beauties” are very common in science, so this paper aims to uncover the reasons and formulation mechanism of information awakening on a more general level. Based on this, the paper will further propose useful strategies to awaken those “sleeping beauties” earlier.

Explanation‐building of case study is used to develop some models of information awakening and also to uncover different types of reasons for triggering academic information to be awakened.

Based on the three basic elements of information utilisation, namely, information value, access channel and user needs, the paper summarises several reasons for information awakening: the information value is re‐mined because of the relevance among various information; different uses of information are discovered; information availability and visibility are improved; information is placed into the appropriate place; and, with time passing by, demands for the information rise.

The presence of excessive “sleeping beauties” is not only a kind of idleness and waste to knowledge, but also may result in aggravation of information redundancy and increasing cost of storage. The revelation of its essence and reasons is not only helpful to establish better management mechanism to awaken “sleeping beauties” and thus to maximise their value, but also helpful to distinguish “sleeping beauties” from “pseudo‐sleeping beauties” as early as possible, so that all that worthless information can be cleared up without hesitation.

Most existing studies remain on the level of collecting instances and interpreting specific cases, but this paper investigates reasons from a more general level. What is more, current understandings are very one‐sided in that they treat information awakening and delayed recognition as the same, so this paper clarifies their differentiation and summarises the reasons comprehensively.

The main research problem is the relationship between the use motivation (UM) and use behavior (UB) of middle-aged and old short videos users and the difference of the influence of the use motivation of middle-aged and old users, a special group, on the usage behavior is analyzed.

By means of a questionnaire survey and in-depth interview, the middle-aged and old-aged users' short video use motivation and behavior and their influence relationship are discussed.

It is found that information appeal is the main motivation of middle-aged and old-aged users to use short videos and users with different social attributes have differences in motivation and there is a significant relationship between motivation and behavior.

The research objective is middle-aged and elderly short video users. And how to promote the transformation of middle-aged and old-aged users' use mentality and record and create their unique bright spots in the big stage of short videos with a more active and independent attitude, is of unique significance not only to the users themselves but also to the media content of this era and the users' existence in the technological change.

This study distinguishes the academic influence of different papers published in journals of the same subject or field based on the modification of the journal impact factor.

Taking SSCI journals in library and information science (LIS) as the research object, the authors first explore the skewness degree of the citation distribution of journal articles. Then, we define the paper citation ratio as the weight of impact factor to modify the journal impact factor for the evaluation of papers, namely the weighted impact factor. The authors further explore the feasibility of the weighted impact factor in evaluating papers.

The research results show that different types of skewness exist in the citation distribution of journal papers. Particularly, 94% of journal paper citations are highly skewed, while the rest are moderately skewed. The weighted impact factor has a closer correlation with the citation frequency of papers than the journal impact factor. It resolves the issue that the journal impact factor tends to exaggerate the influence of low-cited papers in journals with high impact factors or weaken the influence of high-cited papers in journals with low impact factors.

The weighted impact factor is constructed based on the skewness of the citation distribution of journal articles. It provides a new method to distinguish the academic influence of different papers published in journals of the same subject or field, then avoids the situation that papers published in the same journal having the same academic impact.

Purpose: Despite the significance of filial piety in intergenerational relationships and its important influence on parental health and well-being, few studies have explored the personal meaning of filial piety to older parents. This qualitative study aims to address this question.

Design: Responses to an open-ended question of “What makes a filial child in your view?” from a sample of 432 older parents in a rural Chinese county were collected face-to-face and analyzed using content analysis.

Findings: The personal meaning of filial piety varies. Seven broad themes emerged. These include widely persistent traditional filial piety beliefs (Be obedient, Respect, and Maintain frequent contact and show emotional care), filial piety values similar to filial obligations described in Western cultures (Help older parents when in times of need and Be a good citizen and take good care of themselves and their families), and traditional filial piety norms in the absolute form (Take care of every aspect of the parents’ life and Provide financial and material support to parents). Themes were also compared with dimensions of the intergenerational solidarity model.

Originality: Findings reflect the coexistence of traditional and modern filial values in relation to participants’ interpretation of filial piety, indicating that traditional filial piety beliefs are fading even in one of the least developed areas in China. Implications for interventions enhancing offspring’s filial performance are discussed.

Research limitations: Future studies on the understanding of filial piety from the perspective of offspring are warranted to draw a holistic picture of this topic.

This paper aims to study the mechanism of hydrogen embrittlement in 12Cr2Mo1R(H) steel, which will help to provide valuable information for the subsequent hydrogen embrittlement research of this kind of steel, so as to optimize the processing technology and take more appropriate measures to prevent hydrogen damage.

The hydrogen diffusion coefficient of 12Cr2Mo1R(H) steel was measured by the hydrogen permeation technique of double electrolytic cells. Moreover, the influence of hydrogen traps in the material and experimental temperature on hydrogen diffusion behavior was discussed. The first-principles calculations based on density functional theory were used to study the occupancy of H atoms in the bcc-Fe cell, the diffusion path and the interaction with vacancy defects.

The results revealed that the logarithm of the hydrogen diffusion coefficient of the material has a linear relationship with the reciprocal of temperature and the activation energy of hydrogen atom diffusion in 12Cr2Mo1R(H) steel is 23.47 kJ/mol. H atoms stably exist in the nearly octahedral interstices in the crystal cell with vacancies. In addition, the solution of Cr/Mo alloy atom does not change the lowest energy path of H atom, but increases the diffusion activation energy of hydrogen atom, thus hindering the diffusion of hydrogen atom. Cr/Mo and vacancy have a synergistic effect on inhibiting the diffusion of H atoms in α-Fe.

This article combines experiments with first-principles calculations to explore the diffusion behavior of hydrogen in 12Cr2Mo1R(H) steel from the macroscopic and microscopic perspectives, which will help to establish a calculation model with complex defects in the future.