• Asian Journal of Business Environment
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• 제2권1호
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• pp.19-23
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• 2012

The economic exchanges have become increasingly frequent between China and Korea and the average annual growth rate of the total trade volume has increased by 30% since the establishment of diplomatic relations between the two countries. With the rapid economic growth and industrial upgrading of China, there are changes in the investment of Korea in China and domestic demand of China, and the trade structure of Sino- Korea has changed a lot in recent years. The changes have mainly manifested in the following aspects, including the increased proportion of high-tech products, raw materials and the intra-industry trade, the decreased proportion of consumer goods, the inter-industry trade and the trade deficit of China. With the development of the situation of international economy, the scale of Korea and China trade will continue to expand and the structure of Korea and China trade will also keep on changing in the long run.

• Clinical and Experimental Reproductive Medicine
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• 제8권2호
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• pp.29-33
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• 1981

Vesectomy has been increased as a popular method of birth control because it is simpler than other methods for men. But the vasectomy results in several problems such as relation to effect changes on the structure and function of the reproductive organ. The fate of non-ejaculated spermatozoa is postulated by some authors that those are disappeared by a progress of dissolution and reabsorption in the epididymis, and we have attempted to prove the true state of sperm-acrosome on the fine structure in vasectomized rats. The results were as follows: 1. Apical segments of the acrosome were swollen similar to the shape of club in many spermatozoa. 2. Discontinuities of the outer and inner acrosomal membranes were occasionally noted and there were complete losses of acrosomes in the certain place. 3. There was no evidence of significant changes in the nuclear structure, nor dilatation of the subacrosomal space. 4. Vasectomy might effect destructive changes in the acrosomes of the non-ejaculated spermatozoa in situ.

• Smart Structures and Systems
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• 제30권5호
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• pp.463-477
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• 2022

In this paper, a hybrid vibration-impedance-based damage monitoring approach is experimentally evaluated for prestressed concrete (PSC) structures with local strand breakage. Firstly, the hybrid monitoring scheme is designed to alert damage occurrence from changes in vibration characteristics and to localize strand breakage from changes in impedance signatures. Secondly, a full-scale PSC anchorage is experimented to measure global vibration responses and local impedance responses under a sequence of simulated strand-breakage events. Finally, the measured data are analyzed using the hybrid monitoring framework. The change of structural condition (i.e., damage extent) induced by the local strand breakage is estimated by changes in a few natural frequencies obtained from a few accelerometers in the structure. The damaged strand is locally identified by tomography analysis of impedance features measured via an array of PZT (lead-zirconate-titanate) sensors mounted on the anchorage. Experimental results demonstrate that the strand breakage in the PSC structure can be accurately assessed by using the combined vibration and impedance features.

• 한국실내디자인학회논문집
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• 제21권1호
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• pp.203-210
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• 2012

Since a private museums started in Europe 17C, many private museums established for high-class people like aristocrats to collect and to keep art works and to appreciate for limited members. After the French Revolution in 18C, the publicity became an important social issue through all European regions, and the museum gradually changed into public ones. Like that, as the concept of museum changed, its social role as well as its function was also changed. The concept of collection and display or preservation changed into the concept of exhibition and appreciation featuring the publicity. With the year-round exhibition, a classical concept, the planned-exhibition, a new active concept set as an important factor for a museum's projects. The latter concept embraces new social issues. Therefore as the space for planned-exhibitions reflecting social issues every season was needed, a museum sets its planned-exhibition space with the changeability, and gradually expands this kind of space in size. It is expected that planned-exhibition spaces characterized as the changeability may give some changes on the flow of a museum's overall space, and may have substantial influences on the flow. To recognize the changes in a planned-exhibition space's influence on the museum, this study selected some national, public museums having the planned-exhibition space, and investigated their influences on each museum's overall space structure through the analysis on space syntax. This study assumed the change of planned-exhibition space as the changes in the number of convex spaces, and measured it. And to understand the planned-exhibition's changes on a museum's overall spaces, such changed assumed as the numeric changes in convex spaces and measured them. In addition, the numeric changes's influence on the overall space structure was analyzed by measuring the overall space's average integration level. Through the above two factors, the 3 research methodologies and analyzed results were drawn out.

• 한국초등과학교육학회지:초등과학교육
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• 제21권1호
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• pp.13-24
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• 2002

This study examined the knowledge structure constructed by children before formal instruction, and successive changes in the structural complexity of knowledge during the learning of the 'Structure and Function of Plants' unit. The researchers let the 5th graders draw the first draft of their concept maps in order to examine the pre-existing knowledge structure concerned with the unit and also four concept maps after completing every fourth lesson. Each concept map drawn by children on the basis of the previous one showed the degree of their current understanding on the structure and function of plants. The results revealed that only two levels of hierarchy and five relationships among the components of the first concept map(relationship, hierarchy, cross link and example) were proven to be valid in terms of conceptual relevance. According to the standard map, there was no change in hierarchy from the 2nd to the 3rd map, and in example from the 2nd to the 4th map. However, the gradual and successive increases of the scores in all components appeared in the children's maps throughout the unit. Knowledge restructuring occurred strongly in the early periods from the 1st to the 6th lesson, and the significant stable changes in tuning and accretion appeared throughout the whole lessons. The results also showed that there were no significant gender differences on the 5th grader's knowledge structuring.

• 한국소음진동공학회논문집
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• 제22권11호
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• pp.1144-1151
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• 2012

A damage in structure alters its dynamic characteristics. The change is characterized by changes in the modal parameter, i.e., modal frequencies, modal damping value and mode shape associated with each modal frequency. Changes also occur in some of the structural parameters; namely, the mass, damping, stiffness matrices of the structure. In this paper, evaluation of changes in stiffness matrix of a structure is presented as a method not only for identifying the presence of the damage but also locating the damage. It is shown that changed stiffness matrix can be accurately estimated a sensitivity coefficient matrix derived from modifying mode shapes, First, with 4 story shear structure models, the effect of presence of damage in a structure on its stiffness matrix is studied. By using these analytical model, the effectiveness of using change of stiffness matrix in detecting and locating damages is demonstrated. To validate the predicted changing stiffness and its location, the obtained results are compared to the reanalysis result which shows good agreement.

• 정보관리학회지
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• 제22권2호
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• pp.205-228
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• 2005

이 연구는 웹정보원의 지적 구조를 동시링크분석을 이용하여 시기별 변화와 검색엔진별 차이를 중심으로 분석하였다. 지적 구조의 시기별 변화를 분석한 결과, 이차원 지도상에 나타난 웹정보원의 군집과 위치는 6년간의 시간흐름에 따른 지적 구조의 변화를 나타냈다. Altavista와 MSN Search 검색엔진을 대상으로 지적구조의 차이를 분석한 결과, 웹정보원 지도에 나타난 전체적인 지적 구조는 유사한 양상을 나타냈지만, 몇몇 웹정보원의 경우 소속 군집이 달라지는 경우가 발생했다. 인쇄 정보원에 적용되던 동시인용기법이 웹정보원에 대한 통시적 분석에도 응용될 수 있음을 확인하였다.

• Biomolecules & Therapeutics
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• 제28권3호
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• pp.230-239
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• 2020

Previous studies have shown disrupted synaptic plasticity and neural activity in depression. Such alteration is strongly associated with disrupted synaptic structures. Chronic stress has been known to induce changes in dendritic structure in the basolateral amygdala (BLA) and medial prefrontal cortex (mPFC), but antidepressant effect on structure of these brain areas has been unclear. Here, the effects of imipramine on dendritic spine density and morphology in BLA and mPFC subregions of stressed mice were examined. Chronic restraint stress caused depressive-like behaviors such as enhanced social avoidance and despair level coincident with differential changes in dendritic spine structure. Chronic stress enhanced dendritic spine density in the lateral nucleus of BLA with no significant change in the basal nucleus of BLA, and altered the proportion of stubby or mushroom spines in both subregions. Conversely, in the apical and basal mPFC, chronic stress caused a significant reduction in spine density. The proportion of stubby or mushroom spines in these subregions overall reduced while the proportion of thin spines increased after repeated stress. Interestingly, most of these structural alterations by chronic stress were reversed by imipramine. In addition, structural changes caused by stress and blocking the changes by imipramine were corelated well with altered activation and expression of synaptic plasticity-promoting molecules such as phospho-CREB, phospho-CAMKII, and PSD-95. Collectively, our data suggest that imipramine modulates stress-induced changes in synaptic structure and synaptic plasticity-promoting molecules in a coordinated manner although structural and molecular alterations induced by stress are distinct in the BLA and mPFC.

• 한국환경과학회지
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• 제18권1호
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• pp.99-111
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• 2009

In this study vegetation structure was monitored focusing on slanting surface of stream for the purpose of developing a management plan and ecological restoration of small stream in Paju. The study was conducted by types of geographical structure, yearly flora, naturalization rate changes, actual vegetation changes, plant community changes. Slope area of small stream in Paju was varied in the slope range of $10{\sim}35^{\circ}$. The survey results of yearly flora showed that 37 species appeared in 2000, 55 species in 2001, 95 species in 2002, and 125 species in 2003. Therefore, the trend of continuous increase of flora each year was observed. In the case of yearly changes of actual vegetation, indigenous wetland herb community including Phragmites communis$(19.99%{\rightarrow}18.42%{\rightarrow}19.60%)$ did not show substantial changes in the area, while the influence of controlled flora such as Humulus scandens$(8.86%{\rightarrow}5.26%{\rightarrow}9.73%)$, and Ambrosia artemisiifolia$(1.06%{\rightarrow}1.43%{\rightarrow}6.93%)$ were increased. The vegetation structure investigated by 18 preset belt-transects also indicated that Phragmites communis and Miscanthus sacchariflorus were maintaining the status or decreasing the population, while the population of Humulus scandens, Ambrosia artemisiifolia, Setaria viridis, and Erigeron canadensis were greatly increased. Our proposal management to restore ecology is as follows: first, preservation and restoration of Phragmites communis landscape; second, restoration of potential stream vegetation community; third, selection and removal of controlled plants.

• 한국건설관리학회논문집
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• 제5권5호
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• pp.109-116
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• 2004

우리나라 건설기업들은 최근 경제 위기를 겪으면서 대외적으로 커다란 환경변화의 요구에 직면해 왔다. 내$\cdot$외부의 환경변화는 기업의 경영조직에 많은 영향을 끼치고 이러한 경영조직은 기업의 경영성과와 밀접한 관계를 가지고 있다. 이에 대응하여 건설기업들은 환경변화에 적응하고 경영성과를 증진시키기 위한 일환으로 기업 내 구조조정, 경영혁신, 조직개선 등의 명목으로 기업경영조직의 개선 노력을 기울이고 있다. 즉, 기업성장에 도움이 되지 않는 조직 구조는 오히려 기업에 역효과로 작용하게 되므로 기업은 가치를 높일 수 있는 효율적인 조직구조를 갖추어야 한다. 또한 향후 환경변화에 유연하게 대처할 수 있는 경영조직의 개발과 구축은 기업의 경영성과를 증대할 수 있는 중요한 기반이 될 수 있다. 이에 본 연구에서는 설문 및 자료조사를 통하여 기업의 조직구조를 분석하고 이를 유형화 한 후 OLC측면의 조직구조 형태분석으로 기업발전단계에 적정한 조직을 설계할 수 있는 모형을 제시하고자 한다.