• Journal of Korean Society of Water and Wastewater
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• v.27 no.1
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• pp.129-138
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• 2013

Water interruption is often caused by a rupture in the branch-like singular pipeline. This will cause critical complaints from household and may decrease public service quality. As an alternative of singular pipeline, additional parallel pipeline could be installed for sustainable water supply. This system is called double pipeline system and able to be utilized for water transmission line between treatment plant and distribution reservoir. Construction of double pipeline was thought to increase capital cost, which can be an issue to waterworks authorities. Reducing capital cost was possible by means of installing connectors between two parallel pipelines because of reduced diameter of each pipe. To obtain optimal design condition for connectors, it was necessary to compare water pressure according to accident location, to investigate flow according to connection pipe spacing, connection pipe diameter, and aging of pipe. Reliable and economical connection layouts were determined based on these results. The cost estimation for each design condition was carried out. Cost was approximately reduced by 20 ~ 30 % compared to the double pipeline without connections. In addition to this, connection between double pipelines could expect extra benefits for maintenance since the pipe could be repaired and rehabilitated without interruption.

• Korean Journal of Metals and Materials
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• v.48 no.12
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• pp.1070-1077
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• 2010

The creep rates of polycrystalline $L1_2$-ordered $Co_3Ti$ and B2-ordered NiAl-Hf intermetallics decrease appreciably with the fine precipitation of the coherent disordered fcc Co-rich phase and $Ni_2AlHf$ phase. With B2-ordered NiAl containing $L2_1-Ni_2AlHf$ precipitates, transmission electron microscope observations of the interaction between dislocations and spherical precipitates revealed that the dislocations tend to be strongly attracted to the particle interfaces during the creep deformation. On the other hand, with $L1_2$-ordered $Co_3Ti$, the significance of the threshold stress is discussed based upon the transmission electron microscope observations of the interaction between dislocations and precipitates. The superdislocations produced during deformation tend to be strongly attracted and dissociated as they meet the coherent disordered precipitates because the anti-phase boundary energy in the disordered phase was zero. An extra force required to pull the dislocations out of the disordered particles during the creep deformation establishes the threshold stress which is beneficial for improving creep strength under lower stresses.

• KSBB Journal
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• v.23 no.6
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• pp.529-534
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• 2008

The reactive oxygen species generated by ultraviolet rays causes various types of cutaneous damage, such as lipid peroxidation and denaturation of the extra-cellular matrix. The accumulation of such damage contributes to skin aging, especially the formation of wrinkles. This study was carried out to develop functional cosmatic by using Oriental herb supercritical extracts (OHSE) for prevention of skin. Effects of OHSE on anti-oxidation, collagenase inhibition and collagen synthesis in normal human fibroblast were investigated. OHSE showed antioxidative activity as high as vitamin C, trolox and DL-penicillamine. Also OHSE showed promotive effect on collagen synthesis and inhibitory effect on collagenase activity. From this results, we conclude that OHSE may have the potential to be conveniently used as an additive in cosmetics for prevention and improvement of skin aging.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.8
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• pp.1095-1101
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• 2016

Ginsenoside Rg1 is a natural compound with various efficacies and functions. It has beneficial effects on aging, diabetes, and immunity, as well as antioxidant and proliferative functions. However, its effect on porcine embryo development remains unknown. We investigated the effect of ginsenoside Rg1 on the in vitro development of preimplantation porcine embryos after parthenogenetic activation in high-oxygen conditions. Ginsenoside treatment did not affect cleavage or blastocyst formation rates, but did increase the total cell number and reduced the rate of apoptosis. In addition, it had no effect on the expression of four apoptosis-related genes (Bcl-2 homologous antagonist/killer, B-cell lymphoma-extra large, Caspase 3, and tumor protein p53) or two metabolism-related genes (mechanistic target of rapamycin, carnitine palmitoyltransferase 1B), but increased the expression of Glucose transporter 1 (GLUT1), indicating that it may increase glucose uptake. In summary, treatment with the appropriate concentration of ginsenoside Rg1 ($20{\mu}g/mL$) can increase glucose uptake, thereby improving the quality of embryos grown in high-oxygen conditions.

• Journal of the Korean housing association
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• v.20 no.5
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• pp.123-132
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• 2009

As society increasingly ages, maintaining an independent lifestyle at home becomes an important issue for older people. This study aims to determine old people's housing needs for maintaining an independent lifestyle despite their health status and living arrangements. A total of 438 residents voluntarily took part in a research questionnaire survey through the quota sampling method. The participants were grouped according to age (60-64, 65-69, 70-74, and over 75), gender (male and female), and house type (apartment houses and others). The results are as follows. (1) The senior residents are mostly within a non occupational, low income, and low subjective living status. (2) They are satisfied with their current residence and hope to manage the rest of their life in the same place. (3) Three out of five residents prefer the apartment housing type to other types of housing. The preferred dwelling size, number of rooms, and preference for use of an extra room all varied depending on gender and housing type as well as whether they were a couple or living alone. (4) The older residents have a higher need for a safety system than do the younger residents. Female residents pay more attention to convenience while male residents pay more attention to safety. The non-apartment residents require more modification to fundamental facilities such as a heating and ventilation system, wind protection, and additional storage than do the apartment residents. This study has thoroughly analyzed request characteristics according to basic qualities of the elderly households.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.8
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• pp.348-353
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• 2003

This paper was the research of high voltage suspension insulator (400 [kN]) including pottery stone, feldspar, clay and alumina of 17 [wt%]. The slurry was fabricated after ball milling mixed raw materials. Green compacts were made by the extrusion of jiggering method and were sintered at 1300[$^{\circ}C$] for 50 [min.] in the tunnel kiln. The sintered density was reached to 97% of theoretical density, and the bending strength was 1658 [k $g_{f}$/$\textrm{cm}^2$] and hardness and fracture toughness which was measured by ICL( indentation crack length ) method were 1658 (kgf/$\textrm{cm}^2$) and 27.5 [Gpa], respectively. In measurement of tana and insulation break voltage of 400 (kN) porcelain, tan$\delta$ took some numerical value between 17${\times}$10$_{-3}$ and 61${\times}$10$_{-3}$ and insulation break voltage value was 19.9$\pm$1.4 [㎸/mm]. The test was performed to research whether the shape of pin affect a overvoltage break load or not As a consequence, when a pin was designed a pin diameter 51 [mm] with the bottom form of two-step constructed with straight in the suspension insulator, Insulator showed overvoltage break load 52 [ton] of the highest value and reflected a fine characteristic in aged deterioration test which is one of the accelerated aging test. Also it could be confirmed a fine characteristic through performing the test that electrical property of insulator was established correctly in accordance with IEC 60383-1 standards.s.

• The Journal of Dong Guk Oriental Medicine
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• v.4
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• pp.161-187
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• 1995

This study was perfomed to investigate causes of the senile hypotension, pathogenic mechanism, symptoms, and therapies through medical literatures, recent chinese medical literatures and chinese medical journals. The results are as follows ; 1. The senile hypotension has major symptoms of dizziness, weakness, syncope, palpitation, shortness of breath, and deficiency of Qi. Additionally, it has minor symtoms of letharhy, isomnia, tinnitus, amnesia etc... 2. The prodromal symptoms of Kwul and Kwul are relating to the symptoms of tachycardia, facial pallor, sweating, anxietas, ambiguous consciousness, and fainting. Weakness and dizziness due to deficiency make the symptoms of exhaustion, fatigue, vertigo, lethargy, and brachycardia. 3. The most principal cause of the senile hypotension is deficiency of Shen due to aging, congenital deficiency, and chronic illness. The rest of causes are defciency of Qi and blood, phlegm of retention, stagnation of Qi, blood stasis, blood prostration etc... In the view of the occidental meicine, the causes of the senile hypotension came from the reduction of cardiac output, the decretion of cardiovascular system's extention due to aging, hereditary factor, secondary factor due to exsanguination, diabetes mellitus, C.V.A etc..., and factor of neurogenic system's degeneration. 4. The principal pathogenic mechanisms are the insufficiency of Xing-Yang, the deficiency of Qi in middle jiao, and deficiency of Shen-Qi. The rest of mechanisms are the deficiency of both Qi and blood, stagnation of the Gan-Qi, and the deficiency of Gan and Shen. Zang-Pu Organs have something to do with Xing, Bi, and Shen. 5. As principal therapies, there are warming and recuperation the Xing-Yang, strengthing the middle-jiao and replenishing Qi, replenishing vital essence to tonify the Shen, and warming and recuperation the Shen-Yang. Additionally, the therapies of invigorating the Bi and relieving mental stress, strengthning the Bi and tonifing the Shen, invigorating Qi and nourishing Yin, soothing the Gan and regulating the circulation of Qi, and tonifing the Shen and nourishing the Gan help the cure of the senile hypotension. In prescriptions there are Baohe Yuan Tang, Buzhong Yigi Tang, Zuoguei Yin, Yougui Yin, Guipi Tang, Zhu Fu Tang, Shengmai San, Sini San, and Qi Ju Dihuang Wan. The medical herbs of Astragali Radix, Codonopsitis Pilosulae Radix, Ginseng Radix, Aconiti Tuber, Ephedrae Herba, Cinnamomi Ramulus, Cinnamomi Corfex Spissus, Zingiberis Rhizoma, Polygalae Radix, Liriopis Tuber, Polygonati Sibirici Rhifoma, Lycii Fructus, Schizandrae Fructus, and Glycyrrhizae Radix can be treated. 6. According to the clinical report, the principal causes are the deficiency of Qi, and insufficiency of Yang which symptoms are dizziness, vitality fatigue and acratia, amnesia, body cold and alger of extremity, spontaneous perspiration, and therady and weak pulse. It was improved by taking WenYang YiQi Tang, Zhu Fu Tang about 20-30 days. The improvement was shown on disappearance of subjective symptoms or the ascending of blood pressure to normal figure, and the rate of improvement was over 70%. 7. As regimens, taking warming and recuperating food(a sheep mutton, juglans regia, chiness date, longan aril etc...) and pungent food(chinese green onion, fress ginger, pipers fructns etc...), doing physical training, not being ill in bed at a long time, and preventing descent of blood pressure coming from sudden change of posture are needed. Additionally, the usage of diuretic, abirritant, and depressor needs to be extra cautious.

• Journal of radiological science and technology
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• v.39 no.4
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• pp.651-660
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• 2016

Due to recent population aging, the number of check-up for senior citizens has increased steadily. According to this trend, the market size of dental X-ray equipment and the number of approval and review for these devices have simultaneously increased. The technical document of medical device is required for approval and review for medical device, and medical device companies needs to have work comprehension and expertise, as the document needs to include the overall contents such as performances, test criteria, etc.. Yet, since most of domestic manufacturers or importers of medical devices are small businesses, it is difficult for them to recruit professional manpower for approval of medical devices, and submission of inaccurate technical documents has increased. These problems lead to delay of the approval process and to difficulties in quick entering into the market. Especially, the Ministry of Food and Drug safety (MFDS) standards of a dental extra-oral X-ray equipment, a dental intra-oral X-ray equipment, an arm-type computed tomography, and a portable X-ray system have been recently enacted or not. this guideline of dental X-ray equipment adjusting revised standards was developed to help relative companies and reviewers. For this study, first, the methods to write technical document have been reviewed with revised international and domestic regulations and system. Second, the domestic and foreign market status of each item has been surveyed and analyzed. Third, the contents of technical documents already approved by MFDS have been analyzed to select the correct example, test items, criteria, and methods. Finally, the guideline has been developed based on international and domestic regulation, through close review of a consultative body composed of academic, industrial, research institute and government experts.

• Journal of the Korean association of regional geographers
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• v.6 no.2
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• pp.21-40
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• 2000

The retail trades in many countries have changed recently according to the high quality, diversification, and marked individuality of consumer needs. Under the continually competing system of the WTO agreement, corporations based in the USA and the EU try to raise their market share in other countries so it is inevitable for Korean retail enterprises to compete with them. This paper is aimed at contributing to the efficient growth for Korean retail trade from the analysis of the development process in retail trade and its changing locations comparing Korea and the USA. Retailers in the USA have practiced diversified marketing strategies considerably in order to survive in a rapidly changing retailing environment. American retailing, which has the most advanced marketing system in the world, has been of growing concern to marketing strategies in Korea. The following is a brief summary of this study. 1. Speedy and higher quality consumption is needed in accordance with the great increase in the single-family household and the female labor force participation both in Korea and in the USA. Senior citizens have become a new consumer group due to the aging population. In the future the retail trade will switch over to diversified retail formats and internet shopping as countries are transformed into information and communication societies. 2. In Korea, the former retail system characterized by markets and department stores has been greatly changed since the late 1980s with emphasis on high quality and convenience in consumption behaviors, with large domestic enterprises and foreign distribution corporations participating in Korean retailing. In the USA, retailing mergers and takeovers by major retails, bankruptcies, and extra-large shopping centers have emerged since the late 1980s. Recently, the USA retailing formats have been changed from the lower price-oriented discount types to the large scale theme parks. Much emphasis was put on entertainment, resorts, and convention centers. On the other hand, non-store types, such as the internet shopping, the CATV shopping, as well as catalog and mail-order sales are drastically increasing, although the proportion of their sales is low up to now. 3. In Korea, most of the retail facilities are concentrated in Seoul and the Metropolitan Region, and the distribution ratio of facilities came to 52% in 1997. The periodic markets, traditional markets which open on a periodic basis, are located mainly in Chollanam-do and Kyungsangbuk-do. The large-sized discount stores have expanded their locations to the over-crowded apartment complexes in new towns, located in the Metropolitan Region, and the large provincial cities, unlike the suburban locations in the USA. Therefore we needed to give attention to the locational relations in retail facilities between Seoul & the Metropolitan Region and rural settlement areas. In the USA, urban areas grew quickly with the development of the automobile in the 1920s, and the location of stores changed from a dispersed style centering around rural areas to a centralized one in urban areas. There is an accelerated growth for suburban areas, which have grown rapidly since 1950. As the membership warehouse clubs were introduced in the 1970s, the decentralization of location was more intensified. On the other hand, inner cities were revitalized by rearranging existing facilities to cope with suburban areas. And the location-free virtual retailing & TV shopping are also growing every year. 4. In view of the above, the continuous and desirable development devices in Korean retail trade are summarized as follows: First, the countermeasures against economies of scale, increase in retailing sales, and rise of a employment percentage in retailing are in need. Second, a scheme of lowering the proportion of food retail sales, and increasing a ratio of durable goods sales need to be worked out. Third, the original ideas are needed to apply positively information, communication and technology to retailing, to graft the traditional types on modem ones based on the social culture. Fourth, strategies are needed to strengthen the competitiveness of our retail trade through cooperation and chains of smaller retailers, the large enterprises participating in the distribution industry. Fifth, in order to realize the above, the retail industry, the administration, and the academic world should support the retail segment with concern and a practical strategy plan.