• Journal of the Korean Geotechnical Society
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• v.22 no.8
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• pp.119-127
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• 2006

Granulated Blast Furnace Slag (GBFS) is produced in the manufacture process of pig-iron and shows a similar particle formation to that of natural sea sand and also shows light weight, high shear strength, well permeability, and especially has a latent hydraulic property by which GBFS is solidified with time. Therefore, when GBFS is used as a backfill material of quay or retaining walls, the increase of shear strength induced by the hardening is presumed to reduce the earth pressure and consequently the construction cost of harbor structures decreases. In this study, using the model sand box (50 cm$\times$50 cm$\times$100 cm), the model wall tests were carried out on GBFS and Toyoura standard sand, in which the resultant earth pressure, a wall friction and the earth pressure distribution at the movable wall surface were measured. In the tests, the relative density was set as Dr=25, 55 and 70% and the wall was rotated at the bottom to the active earth pressure side and followed by the passive side. The maximum horizontal displacement at the top of the wall was set as ${\pm}2mm$. By these model test results, it is clarified that the resultant earth pressure obtained by using GBFS is smaller than that of Toyoura sand, especially in the active-earth pressure.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.2
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• pp.67-76
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• 2023

In this study, in order to enhance the joint capacity between the existing reinforced concrete (R/C) frame and the reinforcement member, we proposed a novel concept of Internal Composite Seismic Strengthening Method (CSSM) for seismic retrofit of existing domestic medium-to-low-rise R/C buildings. The Internal CSSM rehabilitation system is a type of strength-enhancing reinforcement systems, to easily increase the ultimate horizontal shear capacity of R/C structures without seismic details in Korea, which show shear collapse mechanism. Two test specimens of full-size two-story R/C frame were fabricated based on an existing domestic R/C building without seismic details, and then retrofitted by using the proposed CSSM seismic system; therefore, one control test specimen and one test specimen reinforced with the CSSM system were used. Pseudo-dynamic testing was carried out to evaluate seismic strengthening effects, and the seismic response characteristics of the proposed system, in terms of the maximum shear force, response story drift, and seismic damage degree compared with the control specimen (R/C bare frame). Experiment results indicated that the proposed CSSM reinforcement system, internally installed to the existing R/C frame, effectively enhanced the horizontal shear force, resulting in reduced story drift of R/C buildings even under a massive earthquake.

• Korean Journal of Psychosomatic Medicine
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• v.30 no.2
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• pp.172-178
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• 2022

Objectives : Although subclinical depression symptoms are associated with suicidal idea, most research have focused on clinical depression such as major depressive disorder or dysthymia. The aim of this study is to investigate network structure of depressive symptom and to reveal which symptoms are associated with suicidal ideation. Methods : We used part of data from the seventh Korea National Health and Nutrition Examination Survey. Participants were between 19 and 65 years of age (N=8,741). Network analysis with Isingfit model is used to reveal network structure of depressive symptoms and most central symptom and edges assessed by patient health questionnaire (PHQ-9). Results : The most two central symptoms were psychomotor activity and suicidal ideation. The strongest edge was psychomotor activity-suicidal ideation. Suicidal ideation also has strong association with depressive mood and worthlessness. Conclusions : These results suggest that psychomotor activity and suicidal ideation can serve as treatment target for subclinical depression and psychomotor activity, worthlessness and depressed mood may be important factor for early intervention of suicidal ideation.

• Applied Microscopy
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• v.35 no.1
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• pp.41-56
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• 2005

Present study was performed to observe the tegumental ultrastructures by the developmental stages which derived from the experimental life cycle of Spirometra erinacei in laboratory conditions. In SEM view, coracidium was spherical in shape with numerous cilia, and its surface was covered with long cilia, tuberclelike projections with millet-like processes, and small holes. The body surface of procercoid was covered with numerous pointed microtriches except that of frontal pit with stout spine-like ones. However that of cercomer was covered with somewhat sparse blunt-tiped microtriches. Plerocercoids of 3 days old resembled the mature procercoid in shape, and their frontal pits were covered with numerous stout spine-like microtriches. However frontal pit and body surface in more than 5 days old ones were covered with conoid microtriches. On the surface of adult scolex, hairly long filamentous and stout short microtriches were mixedly distributed. Filamentous microtriches were more densely distributed in the anterior portion than in the posterior of scolex. The neck and immature proglottid were covered with only stout short conoid microtriches. In TEM view of coracidia, embryophore and oncosphere were obviously distinguished. The embryophore contained numerous glycogen particles, mitochondria and lipid granules. The cilia on the surface of embryophore rooted in the coracidial sheath, and consisted of 9 pairs of microtubules and 2 core complex. The oncosphere was covered with a thin and unarmed tegument, and was multi-nucleated. The protoplasmic layer of procercoid and plerocercoid consisted of disc-shaped bodies, vacuoles and mitochondria. Their tegumental cells commonly retained a nucleus, granular endoplasmic reticulums and secretory granules. The protoplasmic layer of plerocercoid was more compacted than that of procercoid. From the above results, it was confirmed that the tegumental ultrastructures are something different according to the developmental stages of S. erinacei.

• Journal of Korean Philosophical Society
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• v.105
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• pp.321-350
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• 2008

The purpose of this paper is to identify the difference between Sangsan-Simhak(象山心學) and Yangming-Simhak(陽明心學). This means that the whole history of Sung Confucianism needs to be understood based on changing philosophical paradigm according to the times, not general perception which regards the whole history of Sung Confucianism as Li-Hak (理學) and Sim-Hak(心學). This kind of perception is caused by the general perception which divides Sung Confucianism into Sim-Hak and Li-Hak. We regard the former as Chung-Chu study and the latter as Liu-Yang study. Because of this, Sangsan study is recognized as the former stage study of Yangming study and can not be placed in independent position in whole history of Sung Confucianism. And Sang is regarded that it takes diametrical opposition with Chuhsi study. So it is said that there is no point of sameness among them. But Sangsan study was generated from 'Song-Hak(宋學)' based on paradigm of Li-Hak and Yangming study was generated from 'Ming-Hak(明學)' based on paradigm of Sim-Hak. The difference between 'Song-Hak' and 'Ming-Hak' is generated from proposition called 'Sim is Li (心卽理)' that most research has overlooked. To identify these things, this paper examine the philosophical difference between 'Song-Hak' and 'Ming-Hak' and analyze the proposition 'Sim is Li(心卽理)' that regards Sangsan study and Yangming study as same philosophical system. And this paper identify the philosophical difference between Sangsan study and Yangming study by examining the method that the concept of 'Sim is Li(心卽理)' is applied in moral cultivation. This paper shows that the difference of interpretation about the concept of Li(理), between 'Song-Hak' based on Li paradigm and 'Ming-Hak' based on Ki-Hak(氣學) paradigm, causes different meaning in 'Sim is Li(心卽理)'. Through these, this paper demonstrate the difference between the paradigm of 'Song-Hak' that Chuhsi study and Sangsan study have and the paradigm of 'Ming-Hak' that Yangming study has and the fact which Sangsan study is systematic philosophy of Sung Confucianism in itself not former stage of Yangming study.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.7
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• pp.944-950
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• 1993

Diodes and GaAs have been commonly used in a mixer design until recently. However, diodes are not preferred to use at the front-end of DBS receiver due to the conversion loss large noise. HEMT has larger conversion gain and better noise characteristics comparing with GaAs MESFET. This paper describes the design procedure, structure, and performance of a mixer, utilizaing HEMT designed by OKI Co. . A mixer configuration in which the local oscillator(LO) signal is applied to the gate is used. When the LO power is 0.01 dBm, the conversion gain of 3.7dB is obtained at IF and the 3 dB bandwidth is 400MMz.

• Journal of the Korean GEO-environmental Society
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• v.10 no.4
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• pp.65-71
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• 2009

Hydraulic fracturing technology has been widely applied in the industry for the recovery of the natural resources such as gas, oil and geothermal heat from hot dry rock. During hydraulic fracturing stimulation, multiple cracks are created resulting in mechanical interaction between cracks. Such an interaction influences obtaining hydraulic fracturing key parameters (crack opening, length, and borehole net pressure). The boundary collocation method (BCM) has been proved to be very effective in considering mechanical interaction. However, for better confidence, it needs to be verified by comparison with analytical solutions such as stress intensity factors. In this paper, three cases, single fracture in remote uniaxial tension, single fracture in remote shear stress field and two arbitrary segments in an infinite plane loaded at infinity are considered. As a result, the BCM is proved to be valid technique to consider mechanical interaction between cracks and can be used to estimate the hydraulic fracturing parameters such as opening of the fracture, and so on.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.430-433
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• 2003

Cost, schedule, quality are the essential parts of success of every construction project. It is especially true in high-rise building construction. Among the construction components in high-rise building construction, curtain walls are very important elements for the project success because they take large portion of cost and schedule. However, curtain wall construction process are very complicated, where many entities including designers, suppliers, contractors and even maintenance contractors are involved. Therefore, control and management of their relationships and production process are critical. It is suggested that this can be solved by the concept of Supply Chain Management which is supported by the automated information technology with Radio Frequency Identification. Such concept is defined as 'Automated Life-Cycle Management System Based On SCM' and this study suggests rode map to establish the system.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.48-57
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• 2003

BAT Korea's Factory is the one of the major projects that clearly confirms and demonstrates that Construction Management (CM), provided by a Korean CM Company to the foreign clients, enables them to successfully complete projects; with savings in time and reduction in cost, which it is $15\%$ lower than the cost of the overseas construction. Also, throughout the thorough schedule management, it was possible to commence with manufacturing one month after the completion date. The Key Success Factors was generated by the excellent construction management skills, and more importantly by the confidence gained by the client in giving a CM company full authority for the construction management of the project. This study has focus on elements of construction management applied to this project throughout the concept of 'One Stop Shop', including cost managements, contract management and value engineering etc. We hope that this study will provide useful data to enable public clients to take advantages of construction management, in a similar way to. the private clients, who have already implemented CM actively.

• Journal of the Korea Fashion and Costume Design Association
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• v.12 no.3
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• pp.93-103
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• 2010

The results of comparison and analysis of dynamical features according to Jacquard structure are as follows. Regarding elongation(E) value in tensile property, the value in the direction of course was found to be larger in all Jacquard structure, except floating Jacquard, than the direction of wale. It could be found that, as to bending strength(B) in Bending Property, the value of bending strength in the direction of course smaller in all the textile(structure) except floating than the direction of wale, so that the ability of curve formation is excellent. And in case of floating Jacquard, it showed the smallest value in the direction of course and wale, so that it was interpreted as Jacquard having a soft feel. Blister Jacquard showed the highest value in both directions of course and wale, so that it was evaluated as Jacquard having the hardest touch. With regard to shearing character(G) and shearing hysteresis(2HG) in Shearing Property, Jacquard indicated the lowest value, so it was evaluated as the textile(structure) having high drape the transformation of whose fabric is easy. In addition, normal Jacquard, transfer Jacquard, blister Jacquard showed a high value, so that it could be known they are Jacquards having stiff touch. The study implies that normal Jacquard, bird's eye Jacquard, etc., which well stretch in the direction of a course like tubular Jacquard course, is better to make the margin a little shorter than the basic margin, and Jacquard that well stretches in the direction of wale like ladder's back Jacquard and floating Jacquard is better to make the margin longer and the length shorter than the basic margin.