• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.4
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• pp.413-427
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• 2006

It is necessary to study and develop guidelines for providing comfort and health indoor air quality for office workers since air-tight envelope system of current office building may cause poor indoor air quality. The purpose of this study is to propose guideline for volatile organic compounds in office base on the field study, human health risk assessment and cost-benefit analysis. The field study was conducted to survey the concentrations of volatile organic compounds in indoor air of 69 offices from June to September, 2005 in Seoul and Gyeonggi-do. The rate of excess to guideline of volatile organic compounds in indoor air of new apartment on the Ministry of Environment in Korea(MOE) was surveyed 37.6% for benzene, 6.8% for toluene, and 1.5% for ethylbenzene. As the result of human health risk assessment, mean cancer risk did not exceed 10-6 which is guideline of US.EPA. Also, total hazard index did not exceed 1 which is guideline of US.EPA. Through the cost-benefit analysis of angle on the social-economics to verify the necessary to establish the standards of volatile organic compounds for improvement and development of indoor air quality in office, the present value of benefit was higher than the present value of cost. With the above considerations in mind, it is suggested that the field study for indoor air quality in offices should be expanded and human health risk assessment and cost-benefit analysis be performed th offer scientific data for decision-making of policy for improvement and management of indoor air quality in office.

• Journal of Technologic Dentistry
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• v.23 no.2
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• pp.161-170
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• 2002

The Purpose of this study was to investigate the chemically improvement of metal-ceramics bond strength in the course of recasting Ni-Cr metal composite system with 10wt.%, 20wt.% and 30wt.% aluminum respectively. We have tested the bond strength, micro-structure, chemical composition of each metal composites and metal- ceramic bond interfaces by 3-point bending strength tester, SEM and EDS. We have made the conclusions through this study as follow: 1. The most suitable amount of aluminum to the Ni-Cr metal composite recasting is 20wt. % for improving metal-ceramics bond strength with debonding strength value of 49.54 kgf/mm2. 2. The aluminum must be changed to small spread alumina like phases and second aluminum-metal composites phases in the morphology of Ni-Cr metal composite system by adding during it's casting. These second phases have inclined functional oxide phases mixed with metal elements and they must take roll to improvement of metal-ceramics bond strength. 3. In the case of 30wt.% aluminum appended to Ni-Cr metal composite system, an excess of second inclined functional oxide phases produce cracks and spalling of them apart from it's base material. It must be a important factor of reduction of metal-ceramics bond strength.

• Journal of Acupuncture Research
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• v.28 no.5
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• pp.65-76
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• 2011

Objectives : Study about needle retaining time. Methods : We reviewed the ancient and the present text of China with using the China academic journal(CAJ) of China national knowledge infrastructure(CNKI) Results & Conclusions : 1. Needle retaining time is important in acupuncture, because the therapy effect is influenced by it. 2. The time of needle retaining is up to those conditions like different disease, viscera and bowels(臟腑), meridian and collateral(經絡), obtaining Qi(得氣), seasons, constitution of the patients and acupuncture tools. In ${\ll}$Hwangdineijing(黃帝內經) ${\gg}$, needle retaining time is called by 'Zhiruzhichu(直入直出)', 'Jichu(疾出)', 'Liu(留)', 'Buliu(不留)', 'Jiuliu(久留)' and 'Liu ${\bigcirc}$ hu(留${\bigcirc}$呼)', and the time was shorter than nowadays. 3. The respiration number was counted to check needle retaining time but we can't find out any evidence. Recently in China, 'obtaining Qi(得氣)' and 'Qi arrival(氣至)' is used to check it. 4. Looking into clinical researches, different diseases need different needle retaining time. For example, 20~30min is appropriate time for musculoskeletal system. 60min is for circulatory system, 10~20min is for peripheral facial nerve paralysis. Insomnia and some stubborn diseases need longer time. Cold and heat(寒熱), deficiency and excess(虛實) are always influences the needle retaining as well. 5. It is important to figure out the most effective needle retaining time for different disease with the base of connection between needle retaining time and effect.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.6
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• pp.111-118
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• 2008

In this paper, novel latch-up prevention method that employs power-up sequential switches has been proposed to relieve latch-up problem in liquid crystal display (LCD) driver ICs. These sequential switches are inserted in the 2'nd and 3'rd boosting stages, and are used to short the emitter-base terminals of parasitic p-n-p-n circuit before relevant boosting stages are activated during power-up sequence. To verily the performance of the proposed method, test chips were designed and fabricated in a 0.13-um CMOS process technology. The measurement results indicated that, while the conventional LCD driver If entered latch-up mode at $50^{\circ}C$ accompanying a significant amount of excess current, the driver IC adopting the proposed method showed no latch-up phenomenon up to $100^{\circ}C$ and maintained normal current level of 0.9mA.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.2
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• pp.101-108
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• 2016

We investigated changes in the physiochemical quality of sailfin sandfish sauces fermented with two kojis during long-term storage at room temperature. Four fish sauces, including a control, were prepared by salt-fermentation with soybean koji (S-koji) or rice koji (R-koji) after autolysis. During storage, for 12 months, the color and levels of amino acids, total volatile base nitrogen (T-VBN) and organic acids but not moisture, salt or total nitrogen levels or pH differed markedly according to fish sauce type. The total nitrogen level was highest in S-koji, but there was no difference in the rate of increase in amino acid levels among the four fish sauces during storage. The T-VBN, of autolysis and S-koji were significantly higher than those of the control and R-koji during the entire storage period (P<0.05). The initial organic acid level did not differ among the four fish sauces, whereas it was notably higher in R-koji than in the other sauces at the end of storage. Hunter L, a and b values decreased in all fish sauces with increasing storage time. In conclusion, soybean koji may enhance the levels of nitrogen compounds as well as T-VBN in fish sauce, while rice koji reduced the formation of excess T-VBN and increased organic acid levels during storage at room temperature.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.2
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• pp.25-33
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• 2002

This study was carried out to select the utilizable vegetations for the stabilization of slopes and river banks, landscape creation and water quality cleansing in dams, lakes and streams. In this study, 10 herbaceous plants were investigated for their survival and growth characteristics under complete and partly flooding conditions in the nursery. The ranking order of flooding tolerance based on survival ability showed that Iris pseudoacorus, Phragmites communis and Phragmites japonica were first, Typha angustata, Miscanthus sacchariflorus and Pennisetum alopecuroides were second, and Cymbopogon tortilis, Miscanthus sinensis, Kummerowia striata and Lolium multiflorum were last. That of flooding tolerance base on growth ability showed that Iris pseudoacorus, Phragmites communis, Phragmites japonica, Typha angustata and Miscanthus sacchariflorus were first, Pennisetum alopecuroides, Miscanthus sinensis and Kummerowia striata were second, and Cymbopogon tortilis and Lolium multiflorum were last. Espcially, Miscanthus sacchariflorus, Iris pseudoacorus, Phragmites japonica and Phragmites communis showed good survival and growth abilities when they were complete flooded for 60 days. Also high flooding tolerant species grow as better as flooding period longer under the partly flooding condition. It was found that Pennisetum alopecuroides and Kummerowia striata have excess moisture tolerance because they showed good survival and growth under the partly flooding condition. This study confirmed that the possibilities of utilizing Iris pseudoacorus, Typha angustata, Phragmites japonica, Phragmites japonica, Phragmites communis, Miscanthus sacchariflorus, Pennisetum alopecuroides and Kummerowia striata as the efficient plants for vegetation measures on the flooded slopes of dam and various impoundment sites.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.12
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• pp.1726-1731
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• 2013

The effects of different dietary electrolyte balance (DEB) on growth performance, nitrogen (N) metabolism and some blood biochemical parameters were investigated in 2 to 3 months old growing rabbits. A total of 150 growing rabbits of 2 months age were randomly divided into five groups according to average body weight, with 30 rabbits in each group. The DEB levels of the five experimental diets were -154, -3.16, +201, +347, and +500 meq/kg of dry matter (DM), respectively. There was a 7-d adaptation period and a 23-d experimental period. The results showed that the DEB levels had a quadratic affect on the average daily feed intake (ADFI) (p<0.001). The greatest ADFI was achieved when the DEB level was +201 meq/kg DM. Fecal N (FN) content linearly decreased (0.047), while digestible N (DN), retained N (RN), efficiency of intake N converted into digestible N (DN/IN) and the efficiency of intake N converted into retained N (RN/IN) linearly increased with the DEB increase (0.020, 0.004, 0.021, and 0.049, respectively). Serum phosphorus (P) ion content linearly increased with the DEB increase (p = 0.036). The DEB had a quadratic relationship with serum anion gap (AG) (p = 0.002) and serum parathyroid hormone (PTH) content (p = 0.016). The DEB levels quadratically affected base excess (BE) in the plasma (p<0.001). In conclusion, the DEB unaffected growth performance but affected feed intake, N metabolism and some blood biochemical parameters of growing rabbits.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.5
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• pp.107-115
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• 2014

In this study, we examined the seismic isolation effects due to the difference between the center of mass of the building and the center of stiffness of isolation layer. Because the base isolation technique is a technique that is highly dependent on the performance of seismic isolation devices installed on the seismic isolation layer, we have to examine the horizontal stiffness of seismic isolation devices after making them. If difference between the design stiffness and the actual stiffness of the seismic isolation device occurred, a big problem may be generated in the upper members on the seismic isolation layer. The analytical results show that the more eccentricity increases, the more maximum response acceleration, story shear and the member forces of the upper part of the structure increases, and the damage is expected to be in excess. Therefore, it is recommended that if possible, isolation devices have to be designed to coincide the center of mass of the building with the center of stiffness of isolation layer. If not after making isolation devices, they need to be relocated to prevent the eccentricity.

• Journal of the Korean Society of Propulsion Engineers
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• v.9 no.1
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• pp.35-45
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• 2005

Numerical study is carried out to investigate the effects of chemistry and thermal radiation on the rocket plume flow field at various altitudes. Navier-Stokes equations for compressible flows were solved by a fully-implicit TVD code based on the finite volume method. An infinitely fast chemistry module for hydrocarbon mixture with detailed thermo-chemical properties and a thermal radiation module for optically thick media were incorporated with the fluid dynamics code. The plume flow fields of a kerosene-fueled rocket flying at Mach number zero at sea-level, 1.16 at altitude of 5.06 km and 2.90 at 17.34 km were numerically analyzed. Results showed the plume structures at different altitude conditions with the effects of chemistry and radiation. It is understood that the excess temperature by the chemical reactions in the exhaust gas may not be ignored in the view point of propulsion performance and thermal protection of the rocket base, especially at higher altitude conditions.

• Journal of Haehwa Medicine
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• v.9 no.1
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• pp.661-689
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• 2000

We came to the conculsion after considering all of information from many kinds of books on the cause, pathogenesis and treatment of Flaccidity-syndrome. The results were as follows : 1. Flaccidity-syndrome means limb-relaxation due to muscle atony that isn't able to constraction. It's begun as mild degree from extremities, in some cases ended to quadriplegia or expire. 2. Cause factor and pathogenesis of Flaccidity-syndrome is various. After Lung fluid consuption caused by heat-evil was refered in The Yellow Emperor's Canon of Internal Medicine. They were refered as cause factor that Main channel asthenia, excess of sexual intercourse, wetness-evil, heat-evil gets into the interior, asthenia of the spleen and stomach. Since Ming Dynasty, It's classified to wetness-heat evil, wetness-phlegm, deficiency of vital energy, deficiency of blood, deficiency of yin, blood stasis and indygestion, etc. 3. In the view of treatment of Flaccidity-syndrome, Yangming was selected in The Yellow Emperor's Canon of Internal Medicine, and it's been mean to clear away wetness-heat evil located at Yangming. In the method of acupuncture it was same on the base, and many skills have been used that electronic acupuncture, point-injection theraphy, acupuncture point block, catgut implantaion at acupuncture point, cutaneous acupuncture, auriculo-acupuncture and head acupuncture by the through post generation. 4. Flaccidity-syndrome was defined to weak, disuse and non-pain. Beacause it was non-pain, so medicine to expel wind-evil was prevented to use. But through post generation Flaccidity-syndrome has been treated that is able to cause pain or numness as arthralgia-syndrome. Therefore there is tendency that medicine to expel wind-evil is capable within pathological basement of Flaccidity-syndrome in recent. 5. In the view of west-medicine, Flaccidity-syndrome is diplegia or quadriplegia with sensory disorder, muscle atropy in some cases. And there are spinal disease, peripheral nerve disease, muscular disease, nerve-muscle copula disease. The symptoms are able to amyotomia, numness, sensory disorder, pain.