• Title/Summary/Keyword: Theory U

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Effects of strain on the optical and magnetic properties of Ce-doped ZnO

  • Xu, Zhenchao;Hou, Qingyu;Guo, Feng;Jia, Xiaofang;Li, Cong;Li, Wenling
    • Current Applied Physics
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    • v.18 no.12
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    • pp.1465-1472
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    • 2018
  • The magnetic and optical properties of Ce-doped ZnO systems have been widely demonstrated, but the effects of different strains of Ce-doped ZnO systems remain unclear. To solve these problems, this study identified the effects of biaxial strain on the electronic structure, absorption spectrum, and magnetic properties of Ce-doped ZnO systems by using a generalized gradient approximation + U (GGA + U) method with plane wave pseudopotential. Under unstrained conditions, the formation energy decreased, the system became stable, and the doping process became easy with the increase in the distances between two Ce atoms. The band gap of the systems with different strains became narrower than that of undoped ZnO without strain, and the absorption spectra showed a red shift. The band gap narrowed, and the red shift became weak with the increase of compressive strain. By contrast, the band gap widened, and the red shift became significant with the increase of tensile strain. The red shift was significant when the tensile strain was 3%. The systems with -1%, 0%, and 1% strains were ferromagnetic. For the first time, the magnetic moment of the system with -1% strain was found to be the largest, and the system showed the greatest beneficial value for diluted magnetic semiconductors. The systems with -3%, -2%, 2%, and 3% strains were non-magnetic, and they had no value for diluted magnetic semiconductors. The ferromagnetism of the system with -1% strain was mainly caused by the hybrid coupling of Ce-4f, Ce-5d, and O-2p orbits. This finding was consistent with Zener's Ruderman-Kittel-Kasuya-Yosida theory. The results can serve as a reference for the design and preparation of new diluted magnetic semiconductors and optical functional materials.

Excess Pore Pressure Induced by Cone Penetration in OC Clay (콘관입으로 인한 과압밀점토의 과잉간극수압의 분포)

  • Kim, Tai-Jun;Kim, Sang-In;Lee, Woo-Jin
    • Journal of the Korean Geotechnical Society
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    • v.22 no.11
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    • pp.75-87
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    • 2006
  • A series of calibration chamber tests are performed to investigate the spatial distribution of the excess porewater pressure due to piezocone penetration into overconsolidated clays. It was observed that the excess porewater pressure increases monotonically from the piezocone surface to the outer boundary of the shear zone and then decreases logarithmically, approaching zero at the outer boundary of the plastic zone. It was also found that the size of the shear zone decreases from approximately 2.2 to 1.5 times the cone radius with increasing OCR, while the plastic radius is about 11 times the piezocone radius, regardless of the OCR. Based on the modified Cam clay model and the cylindrical cavity expansion theory, the expressions to predict the Initial porewater pressure at the piezocone were developed, considering the effects of the strain rate and stress anisotropy. The method of predicting the spatial distribution of excess porewater pressure proposed in this study was verified by comparing it with the porewater pressure measured in overconsolidated specimens in the calibration chamber.

An Empirical Study of IT-based Faultlines on Group Performance in Chinese IT Corporations (중국기업에서 IT로 인한 폴트라인이 그룹 퍼포먼스에 미치는 영향에 관한 검증적 연구)

  • Huang, Yun-Chu;Cho, Wan-Sup;Kim, Yeong-Real
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.3
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    • pp.237-248
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    • 2009
  • Faultline theery, introduced by Lau and Murnighan in 1998, adds valuable explanations in addition to what previous demographic studies have explored. However, previous research has not been able to fully integrate the characteristics embedded in the workplace environments, and the influence of faultlines in IT industries has yet to be explored. In this study, IT related influence is given considerable weight into traditional faultline theory and the impact of IT-based faultlines is revealed. Our study indicates that IT-based faultlines have a negative impact on task conflict and process conflict, and these two effectively also effectively mediate the influence of IT-based faultlines to group performance. Two potential moderators are studied and the Tesults indicate that commitment has no moderating effect between IT-based faultlines and group performance while open communication has strong moderating effect. Our empirical study reconfirmed that faultlines are important indicators in group work and also that faultlines are intimately related to various conflicts and group outcomes. We hope our research findings will be beneficial to organizations concerned with effective and efficient group work.

The Duality of Organizational Status and Temporary Employment: The Impact of Evaluated Status and Categorical Status on Temporary Employment in Korean Universities (조직지위의 이원성과 비정규직 고용: 한국대학의 평가형 지위와 범주형 지위가 비정규직 고용에 미치는 영향)

  • Dae-Hun Chunga
    • Asia-Pacific Journal of Business
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    • v.14 no.3
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    • pp.89-101
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    • 2023
  • Purpose - This paper discusses an impact of status on organization's temporary employment. Status not only offers various opportunities for organization but also places constrains on organization. In this perspective, we propose that organization's temporary employment will differ depending on the status. Design/methodology/approach - We predict that organization's evaluated status has a U-shaped relationship with temporary employment because organizational social insecurity varies by the status. Moreover, we predict that organization's categorical status has a positive effect on temporary employment since organizational legitimacy varies with the status and that the effect will be enhanced by an organizational niche. To verify these predictions, we examined a regression analysis using panel data of temporary employment in Korean universities. Findings - The results of regression analysis show that there is a U-shaped relationship between universities' evaluated status and temporary employment. This implies that the middle status university is likely to minimize temporary employment because of conformity pressures. In addition, the results show that university's categorical status has a positive effect on temporary employment and the effect is enhanced by university's market concentration. This suggests that the categorical status has a strong impact on specialist university. Research implications or Originality - This paper contributes the development of temporary employment theory by applying duality of organizational status and identifies the organizational determinants of temporary employment in Korean universities.

A Study on World University Evaluation Systems: Focusing on U-Multirank of the European Union (유럽연합의 세계 대학 평가시스템 '유-멀티랭크' 연구)

  • Lee, Tae-Young
    • Korean Journal of Comparative Education
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    • v.27 no.4
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    • pp.187-209
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    • 2017
  • The purpose of this study was to highlight the necessity of a conceptual reestablishment of world university evaluations. The hitherto most well-known and validated world university evaluation systems such as Times Higher Education (THE), Quacquarelli Symonds (QS) or Academic Ranking of World Universities (ARWU) primarily assess big universities with quantitative evaluation indicators and performance results in the rankings. Those Systems have instigated a kind of elitism in higher education and neglect numerous small or local institutions of higher education, instead of providing stakeholders with comprehensive information about the real possibilities of tertiary education so that they can choose an institution that is individually tailored to their needs. Also, the management boards of universities and policymakers in higher education have partly been manipulated by and partly taken advantage of the elitist ranking systems with an economic emphasis, as indicated by research-centered evaluations and industry-university cooperation. To supplement such educational defects and to redress the lack of world university evaluation systems, a new system called 'U-Multirank' has been implemented with the financial support of the European Commission since 2012. U-Multirank was designed and is enforced by an international team of project experts led by CHE(Centre for Higher Education/Germany), CHEPS(Center for Higher Education Policy Studies/Netherlands) and CWTS(Centre for Science and Technology Studies at Leiden University/Netherlands). The significant features of U-Multirank, compared with e.g., THE and ARWU, are its qualitative, multidimensional, user-oriented and individualized assessment methods. Above all, its website and its assessment results, based on a mobile operating system and designed simply for international users, present a self-organized and evolutionary model of world university evaluation systems in the digital and global era. To estimate the universal validity of the redefinition of the world university evaluation system using U-Multirank, an epistemological approach will be used that relies on Edgar Morin's Complexity Theory and Karl Popper's Philosophy of Science.

A Study on the life of Yoon Cho Chang(尹草窓) and Cho-Chang-Kyeul(草窓訣) (윤초창(尹草窓)의 생애(生涯)와 초창결(草窓訣)에 관(關) 연구(硏究))

  • Kim, Joon Tae;Yoon, Chang Yeul
    • Journal of Korean Medical classics
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    • v.6
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    • pp.189-227
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    • 1993
  • I have studied life of Yoon-Dong-Li(尹東里), who applied Un-Ki(運氣) theory to medicine during Suk-Jong(肅宗) to Joong-Jo(正祖) in Yi-Dynasty and also studied his existing writings named ${\ll}$Cho-Chang-kyeol${\gg}$ (草窓訣). The referenced original work prints were based on 1980's print of Chung-Ku oriental medical society and National Central Library and The academy a korean studies possessed print. Studied with these books, I have concluded as follows. 1. Yoon-Dong-Li(尹東里) courtesy name is Ja-Mi(子美), pen name is Cho-Chang(草窓). He was born in 1705, Suk-Jong(肅宗) 31yrs, and died in 1784, Jeong-Jo(正祖) 8yrs in Yi-Dynasty. He had lineage of third-generationed-doctor and learned medicine from his uncle, Yoon-Woo-Kyo(尹雨敎). His father Yoon-Yi-Kyo(尹이敎) gaved him second influence. 2. Confucianal physician in Ming Dynasty You-Bu(劉溥) respected Ju-Ryeom-Kye(周溓溪), confucianist in Song-Dynasty and You-Bu(劉溥) does not removed grass in front of window (because in chinese, Cho-Charig(草窓) means grass in front of window), and named himself Cho-Chang(草窓). Yoon-Dong-Li(尹東里) followed this suit so called himself Cho-Chang (草窓). 3. The main contents of ${\ll}$Cho-Chang-Kyeol${\gg}$ (草窓訣), (運氣衍論) was written in 1725, when Yoon-Dong-Li(尹東里) was 21yrs old and printed in 1736. The other part of ${\ll}$Cho-Chang-Kyeol${\gg}$ (草窓訣), (用藥篇) was written in 1746. These two parts were not written in the satre time. The (運氣衍論) was written llyears earlier than (用藥). Two parts were combined another day and named (草窓訣). 4. Existing ${\ll}$Cho-Chang-Kyeol${\gg}$ (草窓訣) is transcribed printing with the con tent of "Five elements motion and the six kind of natural factors theory" (五運六氣設). Each edition is generally similar in content, but also has different points each other so naw we hardly finds a complete set of works. 5. ${\ll}$Cho-Chang-Kyeol${\gg}$ (草窓訣) is a first technical book which treats of Un-Ki(運氣) theory in korea. 6. The contents of (運氣衍論) of ${\ll}$Cho-Chang-Kyeol${\gg}$ (草窓訣) is mechanism of diease according to excess and insuffciency of five elements motion and six kinds of nalural faclors.and symploms and priscriptions, includes variated priscriptions. 7. Two parts in (運氣衍論) of ${\ll}$Cho-Chang-Kyeol${\gg}$ (草窓訣), 'Sang-tong' (相通) and 'Kak-Tong' (各通), threats of mochanisim of the disease according to five elements. with the principle of inter-promoting and inter-acting, in the change of ten heavenly stems and five elements motion. 8. In the (用藥篇) of ${\ll}$Cho-Chang-Kyeol${\gg}$ (草窓訣) describes priscription for clinical application according to Un-Ki(運氣) and also records about misuse of medicine. 9. In the ${\ll}$Cho-Chang-Kyeol${\gg}$ (草窓訣), most of priscription are common using one, which also found in ${\ll}$Dong-$\breve{U}$i-Bo-Garm${\gg}$ (東醫寶鑑) and there are few of priscriptions hy Yoon-Dong-Li(尹東里).

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A Study on the Structure Model of Social Welfare Students' Career Preparation Behavior based on Social-cognitive Career Theory (사회인지진로이론에 기초한 사회복지학 전공 대학생의 진로준비행동 구조모형 검증)

  • Yu, Young-Ju;Park, Ji-Sun
    • Journal of Digital Convergence
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    • v.16 no.1
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    • pp.85-92
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    • 2018
  • In this study investigated the factors for the career preparation behaviors of social welfare major students based on Lent et al. (1994)'s Social-cognitive Career Theory so as to provide essential baseline data for establishing proper career support strategies that suit the distinctive nature of social welfare studies. The participants of this study are 132 social welfare major students from three colleges who have completed social welfare field education. This study analyzed the relationship between cognitive factor (outcome expectation), vocational interest factor (major selection satisfaction), goal factor (career decision level), and work performance factor (career preparation behavior). For analysis, SPSS 24.0 and AMOS 24.0 were used. The analysis results are as follows. First, the model's goodness of fit was found to be at a statistically ideal level with CFI=.904, TLI=.887, and RMSEA=.068. Second, the result of analyzing the correlation between the primary variables is as follows: as outcome expectation increased, major selection satisfaction grew, which then increased the career decision level and led to the improvement in career preparation behavior. These results indicate the importance of developing a customized route support program considering the perceived and interesting factors of individual students to improve their career preparation behavior for social welfare majors.

Linguistic Theory in India and Panini (인도의 언어이론과 파니니)

  • 김형엽
    • Lingua Humanitatis
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    • v.1 no.2
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    • pp.123-139
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    • 2001
  • In the history of linguistics in the world the scholars in India could be regarded as the representative linguists, who had provided the cornerstone of the academic development at linguistics. Without looking into the contents of Indian linguistic theories devised and developed in the past it would be almost impossible to account for the origin of descriptive linguistics and historical linguistics. These linguistics trends became full-fledged in 19 and 20 century and are still accepted by a lot of researchers in order to analyze newly revealed languages and train students only coming up the toddling level of linguistic studies. In this paper I will show how far the influence of Indian linguistics has colored the flow of linguistic growth historically. Especially through the analysis of Panini grammar I will prove the intimate relationship between the Indian linguistic theory and the generative grammar - it is the most active theory at present. The methods that Panini applied to constitute the rules like sutra include lots of information, that also could be discovered at the rules postulated in the generative grammar. One of the common features found at both linguistic theories is the simplicity of rule representation. At the generative grammar a rule has to be established without any redundancy. When certain number of sounds like p, b, m show the same phonological. change relevant to lips (labial in linguistic term) different rules need not to be given for each sound separately. It is better to find a way of putting the sounds together in a rule with grouping the 3 sounds with the shared phonetic feature 'labial'. In Panini grammar the form of a rule was decided based on the simplicity, too. For example, sutra 6.1.77 shows the phonological connection between the vowels i, u r 1 and the semi-vowels y, v, r, 1. However, it does not require to postulate 4 individual rules respectively. Instead a rule in which the vowels and the semi-vowels are involved is suggested, and linguistically the rule make it clear that the more simpler the rules will be the better they can reflect the efficiency of human language acquisition. Although the systems introduced at Panini grammar have some sense of distance from the language education itself we cannot deny the fact that the grammar formulates the a turning point of linguistic development. It is essential for us to think over the grammar from the view point of the modem linguistic theories to understand their root and trunk more thoroughly. It will also help us to predict in which way linguistic tendency will proceed to in future.

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Theory and practice of the interlibrary loan service (상호대차(相互貸償) 제도의 이론(理論)과 응용)

  • Chun Myung Sook
    • Journal of the Korean Society for Library and Information Science
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    • v.13
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    • pp.39-71
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    • 1986
  • Interlibrary loan has been a very common library service in the developed countries but it is yet to be actualized formerly in Korea. As Korea is moving toward an information society where all the individual user's request in the library should be met, we need to understand, in detail, the theory and practice of interlibrary loan service. As various information technology has been applied to the libraries, the libraries became the open system. Thus, the libraries become more cooperative, form networks, and make interlibrary loan service available. This study is based on the following three hypothesis formulated from the systems theory. 1. If libraries cooperate each other and form some kind of networks by mail, computers or telecommunications, they become the open system. 2. If a library develops as the open system, interlibrary loan becomes available in the library. 3. If the interlibrary loan system works, the role of the librarians will be changed. The research was carried out by analyzing the various studies about interlibrary loan service and by examining the interlibrary loan systerns presently working in the U.S.. The conclusions are reached deductively from the data. Some of the terminology used are defined as follows: System: a network of interrelated procedures that are joined together to perform an activity or to accomplish a specific objective. It is, in effect, all the ingredient which make up the whole. Cooperation: Working together to benefit participant libraries. Network: a much more structured type of cooperation in which definite regions or areas are connected by electronic or other means to promote interlibrary loaning of materials, in-service traing & other sharing of resources. Interlibrary loan: the lending of books between libraries. The model of cooperation or networks was used to be (1) a star type, (2) a hieranchical type, (3) a distributed type or (4) the combination of aforementioned three. However, the development of the telecommunications and computers enables all kinds of libraires cooperate together. Interlibrary loan service starts with the needs of user's information. The information have to be logically accessed through bibliographies, computers, electronic mails and satellite communications. And the logical access requires the information technology and the libraries become cooperative. The physical access to the information follows next but only traditional method of mail and some commercial service are currently available for this purpose. Therefore, researches are needed to develop this physical access. If the libraries form networks, the microaspect of library changes accordingly as the macroaspect changes. If the libraries . cooperate to become one large world library, the librarians plan, organize, control library operations and report the results. And the librarians work inside and outside of the library to cooperate with other libraries. Only the cooperation of the libraries will enhance interlibrary loan and the Korean librarians have to be prepared to accept the new role of librarianship for the interlibrary loan service.

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Basic Study on Bridge Asset Management Framework and LOS for Efficient Downtown Bridge Maintenance (효율적인 도심지 교량관리를 위한 교량자산관리 체계 및 서비스수준(LOS) 개발을 위한 기초연구)

  • Kim, Gyung-Hyun;Kim, Dong-Jin;Lim, Jong-Kwon;Park, Mi-Yun;Lee, Min-Jae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.5
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    • pp.671-679
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    • 2016
  • Bridges, which constitute one of the key facilities in a social infrastructure, are easily accessed and used by users, so that keeping their performance above a certain level is essential. According to various cases in the U.S., Japan and Europe with a long construction history, it is expected that the maintenance cost of bridges in Korea will increase continuously in the future, so a rational decision making system based on engineering factors is necessary to optimize the performance of and maintain them by allocating the limited budget efficiently. This study is a preliminary basic study for the purpose of developing a common asset management system for managing all of the bridges and maintaining the level of service provided by them. The scope of this preliminary study is limited to bridges in urban areas. The bridge asset management system for bridges in urban areas, their level of service (LOS) and performance measure (PM) were developed by carrying out a workshop consisting of both experts and stakeholders. The analysis on the weights of the value and performance measure for each performance indicator was carried out by using the multi-attribute utility theory and the AHP method. In order to confirm the application of the weight of the performance measure and value of the performance indicator, six bridges in an example city were selected, LOS analysis was applied and its results were reviewed.