• Korean Institute of Interior Design Journal
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• v.15 no.5 s.58
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• pp.120-129
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• 2006

Apartments have become the most popular type of residential building in Korea since the 1960s. The dwelling space should be designed to accomodate various life styles or changing needs of family members. This research is conducted to analyze flexible interior space types of apartments and to improve the architectural planning and design of apartments that can satisfy various needs of residents. In this study, apartments of 10 - 90 pyeongs built in the region of Seoul, between 1998 and 2007, are investigated in terms of the unit plan, the number of open sides, and a distribution of flexible apartment types for each year, Apartments with flexible space are classified into 10 different types, including a flexible type between bedrooms, a flexible type between a bedroom and the livingroom, and a flexible type between the dinning room and the livingroom. According to the composition of unit plans, apartments are also differentiated as a single-corridor type, a double-corridor type, a stairway type, a hall type, and a combination type. According to these classifications, the characteristics of desirable unit plans were analyzed. The results of the analysis showed that, as the unit size of apartments get bigger, the ratio of width/depth of the front side unit plan is increased. This result reflects a trend of high-rise apartments which have an increased number of front-side bays and a shorter depth for better penetration of daylight. In addition, a hall type is found to have a wider front side and shorter depth. According to open sides, a flexible type of the livingroom and the dinning room/kitchen (L-D.K) is found to be most common for the front/back open space, and the livingroom is usually placed on the front/side open space. To meet the changing needs of residents, more research should be conducted on flexible dwelling space.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.4
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• pp.695-704
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• 2016

Rubber deposited during aircraft landing is known as the main cause of reducing surface friction force on wet surfaces. Thus, rubber deposits are removed at regular intervals for sae airplane landing. The high-pressure waterblast method, widely used for the removal of rubber deposits, is regarded as the main cause for the loss of surface material because in this method, water hits the surface directly at a high pressure. In this study, a rubber removal primer is developed to reduce surface damage by lowering the pressure of waterblast relatively during the removal of rubber deposits such that the deposits are removed efficiently even with a lower water pressure. To achieve this, basic materials appropriate for the primer were selected and their performance, penetration rate, and site applicability were evaluated. Based on the evaluations, the proportion of additive required for improving the performance of the basic materials was first determined. Then, the optimum mix ratio was derived through the evaluation of the effect on pavements, and the development of the rubber removal primer was completed.

• Journal of Korean Medical classics
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• v.26 no.4
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• pp.105-116
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• 2013

Objective : If the penetration ratio of the intestinal mucosa is increased, the toxic or unhealthy materials - which should not be absorbed into our bodies - will be come into our bodies. They cause a sort of anti-toxic response or confusion of the immune system, and ultimately bring various types of diseases. This syndrome is related "Poison in Excrement" or "Internal Damage(內傷發癍)" and Leaky Gut Syndrome, so I will study on the relationship between them. Method : Study on the relationship between Dae-Jang-Jung-gyeok and Leaky Gut Syndrome. Result : Korean doctors in ancient times called this syndrome "Poison in Excrement" or "Internal Damage(內傷發癍)" and treated it with "Dae-Jang-Jung-Gyeok(大腸正格)". Leaky Gut Syndrome is a sort of clinical lesion, which allows foreign and harmful toxins in and results in a disorder of the immune system due to the leaking intestinal mucosa. Conclusion : Based upon the analyses, Dae-Jang-Jung-Gyeok and Leaky Gut Syndrome are closely related. Therefore diseases caused by the Leaky Gut Syndrome might be expected to be cured by Dae-Jang-Jung-Gyeok. Particularly the use of treatments for self-immune diseases and allergic diseases such as atopyic dermatitis and articular rheumatism should be expected to reveal a new path of treatment for other disorders such as Leaky Gut Syndrome.

• Journal of Welding and Joining
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• v.16 no.5
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• pp.134-141
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• 1998

In this study, a fillet size for bending fatigue strength of one side fillet welded T-joint, used in box type girder and other welding structure, was investigated by bending fatigue test with or without edge preparation and burn through, with variation of joint shape. As a result, the following conclusions were obtained. (1) In one side fillet welded T-joint, the larger the leg length, the greater the bending fatigue strength. The increase in bending fatigue strength. (2) One side filet welded T-joint with edge preparation showed higher bending fatigue strength than that with twofold-large leg length and without edge preparation. (3) In one side fillet welded T-joint without edge preparation, both manual welding and automatic welding were carried out with same condition. In this case, automatic welding shoed deeper penetration and more increased horizontal leg length than manual welding, so that automatic welding offers grater bending fatigue strength. (4) For one side fillet welded T-joint without edge preparation, the ratio(h/t) of the leg length (h) and the main plate thickness (t) in which toe crack can occur was 1.2 over. (5) In one side fillet welded T-joint with edge preparation, the burn through led to reduced bending fatigue strength. However, this bending fatigue strength was higher than that of one side fillet welded T-joint without edge preparation and with a larger leg length.

• Korean Journal of Veterinary Research
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• v.9 no.1
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• pp.71-78
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• 1969

The present studies were undertaken to determine accurately whether Korean native fresh-water shrimps can serve as the second intermediate host of Clonorchis sinensis. The experimental results obtained were as follows; 1. Metacercaria of Clonorchis sinensis was not discovered in 36 Macrobranchium nipponensis (De Hann), 1992 Palaemon paucidens (De Hann) and Palaemon madestus Heller, and 860 Caridina leucastica Stimpson, collected in Kimhae district, which were digested in artificial gastric juice, using binocular dissecting microscope. 2. Cercariae of the Chinese liver fluke could not approach the body wall of young shrimps due to streaming caused by their motion. 3. Young Palaemon spp. of 247 were divided into two groups and placed in two different room aquariums, one is at high temperature, the other is normal. Then they were contacted with the cercariae. Only 11 degenerated metacercariae were found in 9 Palaemon spp. It was suggested that they had died immediately or within a few days after penetration. Furthermore the temperature did not affect the infective ratio. 4. At the field experimental aquarium, no metacercaria of Clonorchis sinensis was discovered tn 100 Palaemon spp. which had been brought into contact with 5000 Parafossarulus manchouricus two trials. 5. Specific changes in the cercariae mixed with the extract of shrimps meat were not observed through the dissecting microscope. 6. These results suggest that the Korean native shrimps cannot serve as the intermediate host of Clonorchis sinensis.

• Structural Monitoring and Maintenance
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• v.2 no.1
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• pp.35-48
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• 2015

The main objective of this study is to evaluate the long-term performance of various concrete composites in natural marine environment prevailing in the Gulf region. Durability assessment studies of such nature are usually carried out under aggressive environments that constitute seawater, chloride and sulfate laden soils and wind, and groundwater conditions. These studies are very vital for sustainable development of marine and off shore reinforced concrete structures of industrial design such as petroleum installations. First round of testing and evaluation, which is presented in this paper, were performed by standard tests under laboratory conditions. Laboratory results presented in this paper will be corroborated with test outcome of ongoing three years field exposure conditions. The field study will include different parameters of investigation for high performance concrete including corrosion inhibitors, type of reinforcement, natural and industrial pozzolanic additives, water to cement ratio, water type, cover thickness, curing conditions, and concrete coatings. Like the laboratory specimens, samples in the field will be monitored for corrosion induced deterioration signs and for any signs of failureover initial period ofthree years. In this paper, laboratory results pertaining to microsilica (SF), ground granulated blast furnace slag (GGBS), epoxy coated rebars and calcium nitrite corrosion inhibitor are very conclusive. Results affirmed that the supplementary cementing materials such as GGBS and SF significantly impacted and enhanced concrete resistivity to chloride ions penetration and hence decrease the corrosion activities on steel bars protected by such concretes. As for epoxy coated rebars applications under high chloride laden conditions, results showed great concern to integrity of the epoxy coating layer on the bar and its stability. On the other hand corrosion inhibiting admixtures such as calcium nitrite proved to be more effective when used in combination with the pozzolanic additives such as GGBS and microsilica.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1466-1483
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• 2008

This paper discusses the development of an up-to-date computerized CPT (Cone Penetration Test) based soil engineering classification system to provide geotechnical engineers with a handy tool for their daily design activities. Five CPT soil engineering classification systems are incorporated in this effort. They include the probabilistic region estimation and fuzzy classification methods, both developed by Zhang and Tumay, the Schmertmann, the Douglas and Olsen, and the Robertson et al. methods. In the probabilistic region estimation method, a conformal transformation is used to determine the soil classification index, U, from CPT cone tip resistance and friction ratio. A statistical correlation is established between U and the compositional soil type given by the Unified Soil Classification System (USCS). The soil classification index, U, provides a soil profile over depth with the probability of belonging to different soil types, which more realistically and continuously reflects the in-situ soil characterization, which includes the spatial variation of soil types. The CPT fuzzy classification on the other hand emphasizes the certainty of soil behavior. The advantage of combining these two classification methods is realized through implementing them into visual basic software with three other CPT soil classification methods for friendly use by geotechnical engineers. Three sites in Louisiana were selected for this study. For each site, CPT tests and the corresponding soil boring results were correlated. The soil classification results obtained using the probabilistic region estimation and fuzzy classification methods are cross-correlated with conventional soil classification from borings logs and three other established CPT soil classification methods.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.266-292
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• 2007

Round Robin Test (RRT) on ground response analyses was conducted for three sites in Korea based on several site investigation data, which include borehole logs with the N values from standard penetration test (SPT) for all three sites and additionally cone tip resistance profiles for two sites. Three input earthquake motions together with the site investigation data were provided for the RRT. A total of 12 teams participating in this RRT presented the results of ground response analyses using equivalent-linear and/or nonlinear method. Each team determined input geotechnical properties by using empirical relationships and literatures based on own judgment, with the exception of the input motions. Herein, the characteristics of input motions were compared in terms of the frequency and period, and the selection of the depth to bedrock, on which the motions is impinged, was discussed considering geologic conditions in Korea. Furthermore, a variety of geotechnical properties such as shear wave velocity profiles and soil nonlinear curves were investigated with the input properties used in this RRT.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.11a
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• pp.245-249
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• 2008

The purpose of this study is to test performances of 14 types of root barrier materials by applying testing plants and soils suitable for weather and natural features of Korea. For testing plants, Plioblastus pygmaed Mitford A. and Pyracantha angustifolia have been selected. For testing soil, mixture of pearlite and peat moss in 3:1 ratio(volume). Testing container has been fabricated with duplicated structure having inner and outer containers. And the outer container has 2 hinges on its side wall to allow opening and closing. Wet rock wool with 50mm in thickness has been inserted between inner and outer containers to allow root to penetrate through root barrier material and continue to grow. We planted 12 Plioblastus pygmaed Mitford A. and 4 Pyracantha angustifolia per one testing container. Three testing samples have been made for 1 type of root barrier material, which become a total 42 specimens. Planted testing samples have been installed within the greenhouse, which will be observed regularly for 2 years from now on. We started test from July 11, 2008 and had performed intermediate observations every month for initial 3 months. From the 3rd intermediate observation on Sept. 18, we confirmed that 6 types of root barrier materials have penetrated roots. Even though two types of them(EDPM Sheet, Polyethylene Sheet) have been generally used as root barrier materials for roof planting system, all of three testing samples have a lot of penetrated roots. This result proves that it is not reasonable to introduce testing methods of root barrier from Europe or Japan.

• The Journal of Korean Institute for Practical Engineering Education
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• v.2 no.1
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• pp.154-163
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• 2010

The object of this study is to investigate the penetration characteristics according to the change of stacking sequences and curvature radius in the composite laminated shell. They are staked to [02/902]S and [0/902/0]s, their interlaminar number are two and four. We are manufactured to composite laminated shells with various curvature radius. Curvature radius of composite shell is 100, 150, 200mm and ${\infty}$(it's meaning flat-plate). In general, kinetic energy after impact-kinetic energy before impact increased linearly in all specimens. Absorbed energy increased linearly as the curvature increased, and absorbed energy of [02/902]S specimen, which is small interlaminar number, was higher than [0/902/0]s specimen.