• Proceedings of the Korean Geotechical Society Conference
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• 1991.10a
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• pp.312-331
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• 1991

Top-down Method of basement construction technique has been applied for building of the deep basement car park the close proximity of priceless historic buildings in LONDON. Numerical analysis for the prediction of ground movement of the surrounding buildings was performed in order to compare the field data at the various stages of excavation and support. The predicted results from the elasto-plastic analytical method were compared with the observed data and the agreement is very satisfactory. It may be concluded that the system of diaphragm wall supported by the permanent base slabs (Top-Down Method) was proved to be the most effective technique in terms of reducing any critical damage to the surrounding buildings.

• Journal of Computing Science and Engineering
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• v.4 no.2
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• pp.173-187
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• 2010

Recent technological advances in mobile communication systems have made explosive growth in the number of mobile device users worldwide. One of the most important issues in designing a mobile computing system is location management of users. The hierarchical systems had been proposed to solve the scalability problem in location management. The scalability problem occurs when there are too many users for a mobile system to handle, as the system is likely to react slow or even get down due to late updates of the location databases. In this paper, we propose a top-down clustering algorithm for hierarchical location database systems in a wireless network. A hierarchical location database system employs a tree structure. The proposed algorithm uses a top-down approach and utilizes the number of visits to each cell made by the users along with the movement information between a pair of adjacent cells. We then present a modified algorithm by incorporating the exhaustive method when there remain a few levels of the tree to be processed. We also propose a capacity constraint top-down clustering algorithm for more realistic environments where a database has a capacity limit. By the capacity of a database we mean the maximum number of mobile device users in the cells that can be handled by the database. This algorithm reduces a number of databases used for the system and improves the update performance. The experimental results show that the proposed, top-down, modified top-down, and capacity constraint top-down clustering algorithms reduce the update cost by 17.0%, 18.0%, 24.1%, the update time by about 43.0%, 39.0%, 42.3%, respectively. The capacity constraint algorithm reduces the average number of databases used for the system by 23.9% over other algorithms.

• 중국학논총
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• no.67
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• pp.101-121
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• 2020

中国近代以来一直由国家主导推进科学普及运动。 甚至把普及科学知识当作建设富强社会主义国家的重要手段, 致力于科学化运动。 本论文将通过中国的科学普及政策和科学化运动的开展过程, 了解科学在中国如何在理念上实现最大化。 另外, 在大众科学的形成过程中, 将探索国家是如何定义和利用科学的, 在科学知识的生产和形成过程中, 大众的地位和作用如何。 为此, 首先将了解新中国国家政策和法规中反映的科学普及运动的内容, 以既是这些政策的理论,思想源流, 又是民国时期中国'科学化运动'堡垒的杂志《科学中国》为中心, 了解中国近代科学普及运动的性质和发展情况。

• Journal of the Korea Institute of Building Construction
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• v.6 no.4 s.22
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• pp.77-83
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• 2006

The purpose of this study is to measure the straightness of prefounded columns during underground construction stages. There are several causes of an error of prefounded column: (1) columns connected by welding or bolting, (2) by placement of concrete and aggregates around columns, (3) movement during construction, and (4) load applied during construction. The error of column straightness is different for each column, and the tilting of columns is shown in one or two directions between floors. The additional loads caused by the error of straightness may give damage to buildings. This paper presents the measurement results of column straightness, and thus providing a basis for further analysis.

• Geomechanics and Engineering
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• v.31 no.5
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• pp.489-503
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• 2022

A 1257-m-long irregular deep foundation pit located in the central of Nanjing, China was constructed using the combined full-width and half-width top-down method. Based on the long-term field monitoring data, this study analyzed the evolution characteristics of the vertical movement of the columns, internal force of the struts, and axial force of the structural beam and slab. The relevance of the three mentioned above and their relationship with the excavation process, structural system, and geological conditions were also investigated. The results showed that the column uplift was within the range of 0.08% to 0.22% of the excavation depth, and the embedded depth ratio of the diaphragm wall and the bottom heave affected significantly on the column uplift. The differential settlement between the column and diaphragm wall remained unchanged after the base slab was cast. The final settlement of the diaphragm wall was twice the column uplift. The internal force of the struts did not varied monotonically but was related to numerous factors such as the excavation depth, number of struts, and environmental conditions. Additionally, the dynamic force and deformation of the columns, beams, and slabs were analyzed to investigate the inherent relationship and variation patterns of the responses of different parts of the structure.

• Korean Journal of Applied Biomechanics
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• v.15 no.3
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• pp.117-132
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• 2005

It was to study a following research of "A Kinematic Analysis of Air-rolling-breakfall in Judo". The purpose of this study was to analyze the Center of Gravity(COG) variables when performing Air-rolling-breakfall motion, while passing forward over(PFO) to the vertical-hurdles(2m height, take off board 1m height) in judo. Subjects were four males of Y. University squad, who were trainees of the demonstration exhibition team, representatives of national level judoists and were filmed by four 5-VHS 16mm video cameras(60field/sec.) through the three dimensional film analysis methods.COG variable were anterior-posterior directional COG and linear velocity of COG, vertical directional COG and linear velocity of COG. The data collections of this study were digitized by KWON3D program computed The data were standardized using cubic spline interpolation based by calculating the mean values and the standard deviation calculated for each variables. When performing the Air-rolling-breakfall, from the data analysis and discussions, the conclusions were as follows : 1. Anterior-posterior directional COG(APD-COG) when performing Air-rolling-breakfall motion, while PFO over to the vertical-hurdles(2m height) in judo. The range of APD-COG by forward was $0.31{\sim}0.41m$ in take-off position(event 1), $1.20{\sim}1.33m$ in the air-top position(event 2), $2.12{\sim}2.30m$ in the touch-down position(event 3), gradually and $2.14{\sim}2.32m$ in safety breakfall position(event 4), respectively. 2 The linear velocity of APD-COG was $1.03{\sim}2.14m/sec$. in take-off position(event 1), $1.97{\sim}2.22m/sec$. gradually in the air-top position(event 2), $1.05{\sim}1.32m/sec$. in the touch-down position (event 3), gradual decrease and $0.91{\sim}1.23m/sec$. in the safety breakfall position(event 4), respectively. 3. The vertical directional COG(VD-COG) when performing Air-rolling-breakfall motion, while PFO to the vertical-hurdles(2m height) in judo. The range of VD-COG toward upward from mat was $1.35{\sim}1.46m$ in take-off position(event 1), the highest $2.07{\sim}2.23m$ in the air-top position(event 2), and after rapid decrease $0.3{\sim}0.58m$ in the touch-down position(event 3), gradual decrease $0.22{\sim}0.50m$ in safety breakfall position(event 4), respectively. 4. The linear velocity of VlJ.COG was $1.60{\sim}1.87m/sec$. in take-off position(event 1), $0.03{\sim}0.08m/sec$. gradually in the air-top position(event 2), $-4.37{\sim}\;-4.76m/sec$. gradual decrease in the touch-down position(event 3), gradual decrease and -4.40${\sim}\;-4.77m/sec$. in safety breakfall position(event 4), respectively. When performing Air-rolling-breakfall showed parabolic movement from take-off position to air-top position, and after showed vertical fall movement from air-top position to safety breakfall. In conclusion, Ukemi(breakfall) is safety fall method Therefore, actions need for performing safety fall movement, that decrease and minimize shock and impact during Air-rolling-breakfall from take-off board action to air-top position must be maximize of angular momentum, and after must be minimize in touch-down position and safety breakfall position.

• Proceedings of the Korean Geotechical Society Conference
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• 1990.10a
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• pp.111-128
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• 1990

Three numerical analysis carried out for the design of a diaphragm wall were examined by the results of field observation data. Utilizing the wall stiffness, supporting system and construction sequence, the relative merits of those factors on the analysis of diaphragm wall have been investigated and their effects are compared tilth the observed behaviour of the wall. The predicted bending moment and wall displacement by elasto-plastic method agreed well with the observed values. The rigid slab supported system (i.e Top-Down Method) found to be the most effective way of controlling ground movement.

• Korean Journal of Applied Biomechanics
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• v.16 no.2
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• pp.165-174
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• 2006

The purpose of this study was to review the relevant literature about coaching and thereupon, survey the coaching methods used for golfer lesson to reinterpret them and thereby, describe in view of kinetics the swing errors committed frequently by amateur golfers and suggest more scientific golfer coaching methods. For this purpose, kinetic elements were divided into precision and power ones and therewith, the variables affecting such elements were identified. On the other hand, swings were divided into address, take-back, back-swing, back-swing top, down-swing, impact and follow-through to determine 20 variables for each form and thereby, define their errors to determine the relations between their frequency and errors. For this study, a total of 60 amateur golfer were sampled, and their swing forms were photographed with two high-speed digital cameras, and the resultant images were analyzed to determine the errors of each form kinetically, which would be analyzed again with the program V1-5000. The results of this study can be summarized as follows; The kinetic elements could be identified as precision, power and precise power. Thus, setup and trajectory were classified into precision elements, while differences of inter-joint angles, cocking and delayed hitting. Lastly, timing and axial movement were classified into precise power elements. Three errors were identified in association with setup. The errors related with trajectory elements accounted for most (7) of the 20 errors. Three errors were determined for inter-joint angle differences, and one error was associated with cocking and delayed hitting. Lastly, one error was classified into timing error, while five errors were associated with axial movement. Finally, as a result of arranging the errors into a cross table, it was found that the errors were associated with each other between take-back and back-swing, take-back and follow-through, back-swing and back-swing top, and between back-swing and down-swing. Namely, an error would lead to other error repeatedly. So, it is more effective to identify all the errors for every form and correct them comprehensively rather than single out the errors and correct them one by one.

• Archives of design research
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• v.17 no.2
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• pp.23-32
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• 2004

This paper's objective is the analysis of eye-movement recording with visual perception process, the inference of heuristic guidelines with human information processing, and the generation of design principles for practical works. For this objective, it was experimented on that the user's eye-movement recording of interactive media with the Eyegaze Interface System, and analyzed the visual perception process of top-down & bottom-up processing, and inferred the design principles from human information process. Our results provide the implications of design through the analysis of the user's eye-movement recording that were changed according to each menu depth of the interactive media. And, it is proposed that the new concept of heuristic guidelines based on each stage of action that is related to human factors.

• The Korean Journal of Archival Studies
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• no.38
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• pp.225-264
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• 2013

The Purpose of this study is to analyze an active discussion in North America about the issue of community archives governance which mainly focused on 'participatory archives' model and from it, draws implications for the present stage of domestic community archives development. Traditionally in the United States and Canada, local community archives have been built mostly by mainstream cultural institutions such as public archives, public libraries, museums, and historical societies as a part of comprehensive documentation of the society at large. At the same time, they have been processed and managed in accordance with the institution's collection development policy. As a result, most community archives in North America are characterized as top-down community archives model (in contrast with down-up model of 'independent' community archives as a part of grass roots movement in the UK). Recently, the community archives in North America with these characteristics try to overcome their limitations, which result in 'the others' of community archives, through governance, that is, community-institution partnership. Participatory archives model which assumes active community participation in all archives processes is being suggested by archival communities as the effective alternative of governance model of top-down community archives. This discussion of community archives governance suggests progressive direction for the present stage of domestic community archives, which has been built mostly by various mainstream cultural institutions and still has been stayed in 'about the community' stage. Particularly, community outreach strategies that participatory archives model concretely suggests are useful as a conceptual framework in building community archives based on community-institution partnership in reality.