• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.276-279
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• 2008

In order to measure sound transmission loss (STL) of a shipboard window of small size, a special partition is built into the test opening between two reverberation rooms and the specimen is placed in that partition. For high sound insulation, the filler wall often has multi-layered structure such as double-brick wall or buckhead structure with thick steel plate, absorptive material, and sandwich panels. This paper discusses the installation method of a multi-layered filler wall that consist of gypsum boards, lead plates, and glass wool. The experimental results of various wall structures are introduced. The comparison between the results show that the sound bridge effect plays a significant role in lowering the maximum STL of the filler wall. It is also found that the higher the sound insulation performance of the filler wall is, the more important the franking transmission through other side wall of the test facility is.

• Earthquakes and Structures
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• v.18 no.3
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• pp.285-296
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• 2020

Dams are important structures for management of water supply for irrigation or drinking, flood control, and electricity generation. In seismic regions, the structural safety of concrete gravity dams is important due to the high potential of life and economic loss if they fail. Therefore, the seismic analysis of existing dams in seismically active regions is crucial for predicting responses of dams to ground motions. In this paper, earthquake response of concrete gravity dams is investigated using the finite element (FE) method. The FE model accounts for dam-water-foundation rock interaction by considering compressible water, flexible foundation effects, and absorptive reservoir bottom materials. Several uncertainties regarding structural attributes of the dam and external actions are considered to obtain the fragility curves of the dam-water-foundation rock system. The structural uncertainties are sampled using the Latin Hypercube Sampling method. The Pine Flat Dam in the Central Valley of Fresno County, California, is selected to demonstrate the methodology for several limit states. The fragility curves for base sliding, and excessive deformation limit states are obtained by performing non-linear time history analyses. Tensile cracking including the complex state of stress that occurs in dams was also considered. Normal, Log-Normal and Weibull distribution types are considered as possible fits for fragility curves. It was found that the effect of the minimum principal stress on tensile strength is insignificant. It is also found that the probability of failure of tensile cracking is higher than that for base sliding of the dam. Furthermore, the loss of reservoir control is unlikely for a moderate earthquake.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.3
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• pp.307-312
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• 2000

Fasting heat production (FHP) of growing buffalo calves (Bubalus bubalis) in the body weight range of 76 to 236 kg was determined using open circuit respiration chamber. The details of the chambers, calibration of gas analysers and operation of the systems are described. Animals were fasted for 96 hrs during which only water was provided. FHP was determined during next 24 hrs. The mean oxygen consumed, carbon dioxide and methane produced and urinary N excretion per 24 h was $17.03{\ell}$, $11.70{\ell}$, and $0.12{\ell}$ and 0.35 g respectively. The mean respiratory quotient ranged from 0.68 to 0.71, which indicated that post absorptive stage is reached after 96 hrs in growing buffalo calves previously fed ammoniated straw-based ration. Mean FHP of calves was $331.4kJ/kg\;W^{0.75}$. FHP of calves with range of mean body weights of 167 to 235 kg, although nonsignificant but, was almost 12% higher than of calves having mean body weight of 101 kg. Suitable exponent to body weight to describe FHP of buffalo calves was 0.87.

• The Research Journal of the Costume Culture
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• v.18 no.6
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• pp.1063-1075
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• 2010

Studying awareness, importance, satisfaction, and wearing behavior of functional textiles for active silver generation related with gender and age is expected to contribute to clothing products development to improve and maintain their health and marketing strategy fit for user characteristics. For empirical research, a survey was developed and the aged 50 and above were 332 respondents. The results of the study are as follows. First, silver generation considered all the clothing comfort sensations important when wearing clothes, such as tactile sensation, clothing pressure sensation, thermal/wet sensation, and motion sensation in human physiological aspect. Also, stretchy fabrics were ranked first in awareness, the number of wearing times, and satisfaction of comfort functional fabrics. More than 30% of silver generation have fifteen items out of 36 functional clothes. Second, in analysis of awareness by gender on functional clothing products, women were more aware of health/safety-oriented fabrics than men were. Otherwise, men had more knowledge about the water-related properties of functional fabrics than women have, such as water/moisture absorptive and water-repellent/vapor permeable fabrics. While women have more indoor casual wear, men had more active sportswear. Also, women expressed a strong preference to the stretchy function of fabrics.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5823-5828
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• 2015

Micronutrients in food have been found to have chemopreventive effects, supporting the conclusions from epidemiologie studies that consumption of fresh fruits and vegetables reduces cancer risk. The present study was carried out to evaluate the role of querctin (Q) and sodium gluconate (GNA) supplementation separately or in combination in ameliorating promotion of colon tumor development by dimethyl-hydrazine (DMH) in mice. Histopathological observation of colons in mice treated with DMH showed goblet cell dysplasia with inflammatory cell infiltration. This pathological finding was associated with significant alteration in oxidative stress markers in colon tissues and carcinoembryonic antigen (CEA) levels in plasma. Mice co-treated with GNA and Q showed mild changes of absorptive and goblet cells and inflammatory cell infiltration in lamina properia, with improvement in oxidative stress markers. In conclusion, findings of the present study indicate significant roles for reactive oxygen species (ROS) in pathogenesis of DMH-induced colon toxicity and initiation of colon cancer. Also, they suggest that Q, GNA or the combination of both have a positive beneficial effect against DMH induced colonic cancer induction in mice.

• Journal of Korea Technology Innovation Society
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• v.17 no.3
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• pp.584-603
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• 2014

It has become difficult with R&D capabilities of single nation to secure the weapons systems we need, particularly when faced with an increasingly limited budget and transforming into state-of-the-art weapon systems. Therefore, our country is also pursuing international joint technology cooperation for the efficient use of limited defense budgets. In this study, we analyzed the strategy focused on international joint technology cooperation with India. We identified three groups based on the level of defense science and technology cooperation, then we also present a possible cooperation areas and implementation strategies for each group. In addition, we suggest the need for maintenance of the legal system, and professional organizations in order to efficiently access the Indian market.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.11a
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• pp.17-27
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• 2006

Paper could be situated in a cooled environment seasonally or regionally otherwise it is forced to be in a controlled circumstance. In this paper, printing problems on a cooled paper are investigated and characterized in terms of paper properties. For this purposes, various kinds of sample are cooled down under a specially designed freezing device and printed for observing their printability. Causes for poor ink transfer on a cooled paper are suggested due to condensation, surface inactivity, and rheological change in ink film. Paperboards with higher amount of binder, thick and/or multi coat layers are more vulnerable to poor ink trap. Severe drying could cause the same effect as that of higher binder formulation. It is shown that more absorptive porous structure is desirable for better ink receptivity in a cooled status. Printing on a dampened surface may be an indicator for ink transferability on a cooled paper. Finally, desirable directions for papermaker and printshop are suggested.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.2
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• pp.103-114
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• 2012

Nowadays membrane material is widely used for large indoor spaces and long spaces such as traditional market. Thermal insulation and sound field control performance is considered as a main properties for design of such buildings. In this paper sound absorption and thermal insulation properties of membrane material was investigated. Firstly, normal incidence sound absorption coefficient of 10 kinds of glass wool textiles showed that sound absorption coefficient was increased in proportion of thickness and surface density of textile. Sound absorption coefficient of 4 kinds of sound absorptive inner membrane with outer membrane was tested in the reverberation chamber. Sound absorption coefficient of mid frequency range was about 0.4 ~ 0.6. Also, sound absorption coefficient was changed by the air space behind the membrane material. Secondly, sound field control performance was investigated using mock-up space. By the installation of sound absorption membrane material, reverberation time was decreased and speech intelligibility was increased. Finally, thermal resistance and room temperature in two kinds of mock-up rooms were tested, simultaneously. Results of thermal properties showed thermal insulation properties ware increased by adding inner membrane material underneath the outer membrane.

• Journal of the Korean Society of Safety
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• v.21 no.1 s.73
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• pp.86-91
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• 2006

Oil spills caused by the accidents have been occurred from house and factory waste, grounded tanker, the rupture of storage tank and oil pipelines, the deterioration of various industrial facilities, etc. Many oil spills result in contamination of shorelines and workplace. Fire and explosion may happen from these spills. There are several technologies used for clean-up application, which include use of oil dispersing agents, absorbents, solidifiers, booms and skimmers by physical, chemical, and biological methods. Methods for oil spill clean-up operation are classified into the absorption type, gel type and self-swelling type. Porous materials with oil absorptive properties are classified into micropore, mesopore, and macropore depending on their pore sizes. Recently, new porous materials with smaller size have been developed, but the selective oil absorption in water-in-oil interface demonstrates the macro pore size. In this study oil absorption effects were evaluated using the organic porous materials with a complex function of gel type and swelling type. Samples were subjected to analysis by FT-IR spectroscopy and were characterized in terms of gel formation and morphologies. Oil sorption capacity, pressure retention force and gel strength were also measured. From these results, the physicochemical reactivity before and after gelation was verified and the industrial applications of clean-up operation were suggested.

• Korean Journal of Food Science and Technology
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• v.52 no.3
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• pp.244-248
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• 2020

To retain valuable resources, organisms adopt several strategies including coprophagy. Cells covering the outer skin and internal digestive lumen are actively recycled to maintain their integrity. In present study, we suggested that the small intestine can consume dead cells in a manner similar to how it consumes protein from the diet. We examined the eluates from five segments of the mouse small intestine and cecum and 2 segments of the large intestine and small intestine tissue, and detected immunoreactivity with eukaryotic caveolin-1 and β-actin antibodies only in the cecum and 2 segments from the large intestine. Bacterial agitation of the mouse intestine with Shigella disrupted the architecture and absorptive function of the small intestine. Small intestine eluates were immunoreactive with murine caveolin-1 and contained heme as determined by dot blot analysis. We concluded that the body conserves resources in the small intestine by disposing of and recycling shedded cells.