• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.4
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• pp.108-118
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• 2006

The purpose of this study is to investigate the effectiveness of a LQG Hybrid controller to suppress the earthquake disturbance for the building structure. The ground acceleration of N-S component of El-Centro earthquake was scaled to confirm that the building behaved within the elastic range. The tuned mass damper(TMD) on the top floor regulated by LQG algorithm was designed to control the floor displacements. The displacement responses of the hybrid control were compared with those obtained from an active control along with a passive control. The results showed that the LQG hybrid control used approximately 50% less input forces than an active control to satisfy the performance criteria.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.3
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• pp.249-255
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• 2011

Purpose: Placement of endosseous implants in the atrophic maxilla is often restricted because of the lack of supporting bone. In this article, augmentation of the maxillary sinus floor with deproteinized bovine bone to enable insertion of endosseous implants is described. The technique is aimed at providing a cortical layer on top of the graft to ensure a reliable seal of the maxillary sinus and to achieve optimal stability of the bone graft in case of simultaneously placement of dental implants. Methods: The procedure was used in 200 patients (839 implants), using deproteinized bovine bone. The mean follow-up was 28.5 months. No inflammation of the bone grafts nor of the maxillary sinus occurred. The patients received implant supported overdentures or bone-anchored bridges. Results: The survival rate of implant restoration of this study was 97.6%. The total average of marginal bone loss in radiographs was $0.20{\pm}0.38$ mm. Insufficient primary stability, bony quality, and infection were thought to be associated factors in the failed cases. Conclusion: This study documented that deproteinized bovine bone, when used as a grafting material for augmentation of the sinus floor, may lead to proper osseointegration of a endosseous implant.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.1005-1010
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• 2001

Recently, polymer-modified mortar has been studied for proposed use on industrial floors as top layers with thin thicknesses, typically 5~ 15mm. The purpose of this study is to evaluate basic properties of self leveling materials using polymer modifier as kinds of SBR, PAE, SUBA. Superplasticizer and thickener have been included in the mixes to reduce bleeding and drying shrinkage as well as in order to facilitate the workability required. The self leveling materials using four types of polymer dispersion are prepared with polymer-cement ratios which respectively range from 50%, 75%, and were tested for basic characteristics such as adhesion in tension, crack resistance test, rebound test after the preparative tests for unit weight, air content, consistency ratio etc. The results show almost as equal quality as existing commercial industrial flooring when mortar is modified by polymer dispersion. Adhesion in tension of polymer modified mortars using each SBR and PAE emulsion was over 10 kgf/$cm^{2}$. Crack or flaw derived from shrinkage is strongly dependent on the type of polymer dispersion because of each different total solid of polymer. It is judged that polymer modified mortar with self-leveling can be very well suited for Floor-finished.

• KCI Concrete Journal
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• v.13 no.2
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• pp.58-66
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• 2001

Recently, polymer-modified mortar has been studied for proposed use on industrial floors as top coat with thin thickness, typically 5~15mm. The purpose of this study is to evaluate basic properties of self-leveling materials using polymer dispersions as kinds of SBR, PAE, St/BA with thin coat (under 3mm). Superplasticizer and thickener have been included in the mixes to reduce bleeding and drying shrinkage as well as to facilitate the workability required. The self-leveling materials using four types of polymer dispersion are prepared with polymer-cement ratio which respectively range from 50% and 75%, and tested for basic characteristics such as unit weight, air content, flow, consistency change and adhesion in tension. From the test results, the self-leveling materials using PAE emulsion at curing age of 28days are almost equal to those of conventional floor using urethane and epoxy resin. The adhesion in tension of self-leveling mortars using SBR latex and PAE emulsion at curing age of 3days is over 17 kgf/cm$^2$(1.67MPa). Consistency change is strongly dependent on the type of polymer dispersion. It is concluded that the self-leveling materials using polymer dispersions can be used in the same manner as conventional floor using thermosetting resin in practical applications, in the selection of polymer dispersions.

• Korean Institute of Interior Design Journal
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• no.13
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• pp.117-123
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• 1997

The purpose of this study was to examine the current interior conditions of kindergarten and to suggest the interior planning guidelines. Data were collected through questionniare survey including observations and interviews. The sample consisted of 262 kindergarten teachers in Pusav. The data were analyzed by using SPSS-PC. The major findings were as follows: (1) Interior finishes should be chosen based on children's behavioral and developmental characteristics. (2) Considering children's safety and teachers' easy access and observation, classrooms and teachers' room should be located at the first floor, and the public spaces such as playroom and assembly room should be located at the top floor because of noise and circulation problem. (3) The size fo the classroom should be increased based on children's age. (4) The teachers were generally satisfied with location, color, and finishes of each room. There was a significant difference between satisfaction of overall characteristics of rooms and theclasses that teachers are in charge of. (5) Children's developmental characteristics can be an important factor when designing a space for childrev. Even though there were some limitations on this study, the findings can be utilized as a basis for generating interior environmental recommendations for planning a better quality of kindergartev.

• Physical Therapy Korea
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• v.3 no.2
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• pp.1-7
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• 1996

Two standard methods of cane length measurements were compared to find which methods really achieve the elbow flexion of 20 degrees to 30 degrees Twenty-four patients with hemiplegia who were ambulatory participated in this study. Method I : Length of the cane measured from the floor to the top of the greater trochanter. Method II : Length of the cane measured from the floor to the distal wrist crease with the arm at the side. Using an adjustable cane, each individual was fitted according to the two methods, and elbow angle was measured after each adjustment. The elbow angle according to Method I and Method II was $46.4{\pm}20$, $44.3{\pm}12.2$, respectively. No significant difference was found in the elbow angle or the cane length between the two methods. Of the 24 participants, 5(20.8%) measured according to method I and 3(12.5%) measured according to method II showed the elbow angle between 20 degrees and 30 degrees. These low predictive rates of agreement between ideal cane length and actually achieved elbow angle showed that these two methods which have conventionally been accepted as a standard to measure ideal cane length need to be revised through further research.

• Journal of architectural history
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• v.8 no.4 s.21
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• pp.9-24
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• 1999

This study is on architectural characteristics of the existing ㅁ-shaped Yo-Sa with two stories in Buddhist temple. The Yo-Sa has had the function of space for not only monasticism but also living of buddhist priests and been one of the important spaces in Buddhist temple from the beginning of it. The Yo-Sa with two stories appeared mostly in the later Chosun Dynasty, so the origin of the Yo-Sa with two stories is thought that it might relate to the circumstances of temples in the later Chosun Dynasty. Having got in the period of Chosun Dynasty, Buddhism lost the power that he has enjoyed since Korea Dynasty was established and the economic power of temples as well. Because of a change for the worse, the Buddhist priests should manage with reduced income and combine many buildings with various functions into a singular to overcome their circumstances. Therefore a waekened economic power might be a primary factor which urged to change form of Yo-Sa from one-storied to two-storied. The ㅁ-shaped Yo-Sa with two stories have the Dae-Bang-Chae for worship, Seung-Bang for Buddhist's living room in the bottom floor and garnering spaces to store up the agricultural produce, miscellaneous article, etc in the top floor. The composition methods depend on the condition of the lay of land, intentional design, and so on. Therefore, the ㅁ-shped Yo-Sa with two stories shows the diversity of space composition and architectural characteristics.

• Korean Institute of Interior Design Journal
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• v.17 no.5
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• pp.12-22
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• 2008

The purpose of this article is to establish fundamental sources and guidelines of bathroom designs of brand apartments in Korea. The article examines the current conditions of bathroom, satisfaction rates, and preference rates of residents in Mid-sized apartment units of the top five brand apartments based on construction capacity and brand popularity. A total of 427 samples, acquired via internet survey, were analyzed with the statistical computer program SPSS PC+ window version 15.0. The conclusions of the article are as follows: 1) Fixtures and products which fulfill various behaviors, as well as multi-functional space programming, are demanded. 2) Developing clear standards of basic bathroom fixtures and environments is also required in further research and to be applied to practical bathroom design. 3) The bathroom fixtures and environments ought to accommodate all age groups. 4) Respondents preferred a separated dry floor, either toilet or sink portion, to a full-dry or full-wet floor. 5) Respondents of all age groups considered bathroom as a private space, thus it should facilitate various private activities. The results of this study would contribute to adequate and sound bathroom design as key information.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.247-248
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• 2018

In order to secure the variability of long-life housing, dry walls are used. The composite gypsum board panel is the most frequently used infill system for the wall, and it is an excellent construction method in terms of constructability and economic feasibility. However, there are also problems such as the destruction of Ondol pipes at the bottom floor and being unable to fix the light weight steel frame (M-bar) when a variable composite gypsum board panel is used. To solve such problems, a wall with a method of fixing only the top part without fixing the bottom floor is developed, but it is difficult to identify the durability of ceiling frame according to the tensile force of stud and the safety according to the Stiffness and impact resistance (soft body) of ceiling frame. Therefore, this study verified the effectiveness of infill system for the wall by conducting experiment on the stiffness and impact resistance of composite gypsum board panel according to the reinforcement of ceiling frame (wooden frame, double saw-toothed bracket, Cross M-bar). As a result, it was possible to secure the safety of wooden frame while the impact resistance and the Stiffness of double saw-toothed bracket and cross M-bar were not secured.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.9
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• pp.796-803
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• 2004

The stack effect of a new type condenser installed in a high-rise apartment building was studied numerically A sirocco fan is introduced to the new type condenser instead of an axial flow In. The new type condenser intakes the cold air through the lower inlet and exhausts the hot air through the upper outlet. The effects of the building height and frontal wind on the performance of an air-conditioner were analyzed. The performance of an air-conditioner was evaluated by using COP (coefficient of performance) and CGPI (condenser group performance indicator). the hot air was exhausted by the new type condenser at an angle of 50$^{\circ}$ from the outer wall of the building. If there was no draft, the new type condenser installed in the high-rise apartment building had a good performance and its performance on each floor is not influenced by the stack effect. It is shown that the efficiency of the air-conditioner installed in several floors below the top floor decreased when the frontal wind velocity was greater than 8 m/s.