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Development and Economic Effect of Integrated Optimum Operation System using Wide Area Energy (광역에너지이용 통합 최적화 운전 시스템 개발 및 경제적 효과)

  • Lee, Hoon;Kim, Lae-Hyun;Chang, Won-Seok
    • Journal of Energy Engineering
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    • v.18 no.4
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    • pp.221-229
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    • 2009
  • This study develops the optimized operation program which enables effective and economic operation between individual and connected branch offices by analyzing the current status and influential indicators of district heating companies' capital branch offices. Accordingly, the study examines the efficiency of optimized operation program. In doing so, this study has diagnosed and analyzed various factors, such as boilers, pumps, and relevant tags (temperature, pressure, fuel amount) through investigation of individual branch offices, and finally succeeded in developing wide-ranging data base by factor covering one-year time period. Additionally, after running the optimized operation program, different branch offices, optimum preference has turned out "incinerator receiving heat from KEPCO>CHP >PLBs>PLBw." Meantime, except the connected offices, there has been no big difference between actual and optimum operation program in branch offices. Meanwhile, the integrated optimum operation program has made it possible the most optimal result only via the connecting supply and demand heat without changing received Heat from KEPCO which is the same as total productive heat. The result has showed that the reduction percentage per day is 2.45~6.80%, and the reduction cost per day is 22,727~60,077 thousand won given the randomly selected sample days. In particular, winter time shows the highest demand with the largest reduction cost whereas summer time illustrates the lowest demand with the smallest reduction cost. Given this result, reduction cost per year compared to actual heat production cost for one year theoretically would be 84 hundred million won. Also, the economic effect showed that the reduction cost percentage per year is more than 2.74% on heat production cost per year for all capital branch offices.

Research Direction for Functional Foods Safety (건강기능식품 안전관리 연구방향)

  • Jung, Ki-Hwa
    • Journal of Food Hygiene and Safety
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    • v.25 no.4
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    • pp.410-417
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    • 2010
  • Various functional foods, marketing health and functional effects, have been distributed in the market. These products, being in forms of foods, tablets, and capsules, are likely to be mistaken as drugs. In addition, non-experts may sell these as foods, or use these for therapy. Efforts for creating health food regulations or building regulatory system for improving the current status of functional foods have been made, but these have not been communicated to consumers yet. As a result, problems of circulating functional foods for therapy or adding illegal medical to such products have persisted, which has become worse by internet media. The cause of this problem can be categorized into (1) product itself and (2) its use, but in either case, one possible cause is lack of communications with consumers. Potential problems that can be caused by functional foods include illegal substances, hazardous substances, allergic reactions, considerations when administered to patients, drug interactions, ingredients with purity or concentrations too low to be detected, products with metabolic activations, health risks from over- or under-dose of vitamin and minerals, and products with alkaloids. (Journal of Health Science, 56, Supplement (2010)). The reason why side effects related to functional foods have been increasing is that under-qualified functional food companies are exaggerating the functionality for marketing purposes. KFDA has been informing consumers, through its web pages, to address the above mentioned issues related to functional foods, but there still is room for improvement, to promote proper use of functional foods and avoid drug interactions. Specifically, to address these issues, institutionalizing to collect information on approved products and their side effects, settling reevaluation systems, and standardizing preclinical tests and clinical tests are becoming urgent. Also to provide crucial information, unified database systems, seamlessly aggregating heterogeneous data in different domains, with user interfaces enabling effective one-stop search, are crucial.

Optimization for Underwater Welding of Marine Steel Plates (선박용 강판의 수중 용접 최적화에 관한 연구)

  • 오세규
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.20 no.1
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    • pp.49-59
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    • 1984
  • Optimizing investigation of characteristics of underwater welding by a gravity type arc welding process was experimentally carried out by using six types of domestic coated welding electrodes for welding of domestic marine structural steel plates (KR Grade A-1, SWS41A, SWS41B,) in order to develop the underwater welding techniques in practical use. Main results obtained are summarized as follows: 1. The absorption speed of the coating of domestic coated lime titania type welding-electrode became constant at about 60 minutes in water and it was about 0.18%/min during initial 8 minutes of absorption time. 2. Thus, the immediate welding electrode could be used in underwater welding for such a short time in comparison with the joint strength of in-atmosphere-and on-water-welding by dry-, wet-or immediate-welding-electrode. 3. By bead appearance and X-ray inspection, ilmenite, limetitania and high titanium oxide types of electrodes were found better for underwater-welding of 10 mm KR Grade A-1 steel plates, while proper welding angle, current and electrode diameter were 6$0^{\circ}C$, above 160A and 4mm respectively under 28cm/min of welding speed. 4. The weld metal tensile strength or proof stress of underwater-welded-joints has a quadratic relationship with the heat input, and the optimal heat input zone is about 13 to 15KJ/cm for 10mm SWS41A steel plates, resulting from consideration upon both joint efficiency of above-100% and recovery of impact strength and strain. Meanwhile, the optimal heat input zone resulting from tension-tension fatigue limit above the base metal's of SWS41A plates is 16 to 19KJ/cm. Reliability of all the empirical equations reveals 95% confidence level. 6. The microstructure of the underwater welds of SES41A welded in such a zone has no weld defects such as hydrogen brittleness with supreme high hardness, since the HAZ-bond boundary area adjacent to both surface and base metal has only Hv400 max with the microstructure of fine martensite, bainite, pearlite and small amount of ferrite.

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Dynamic Characteristics of Water Column Properties based on the Behavior of Water Mass and Inorganic Nutrients in the Western Pacific Seamount Area (서태평양 해저산 해역에서 수괴와 무기영양염 거동에 기초한 동적 수층환경 특성)

  • Son, Juwon;Shin, Hong-Ryeol;Mo, Ahra;Son, Seung-Kyu;Moon, Jai-Woon;Kim, Kyeong-Hong
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.18 no.3
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    • pp.143-156
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    • 2015
  • In order to understand the dynamic characteristics of water column environments in the Western Pacific seamount area (approximately $150.2^{\circ}E$, $20^{\circ}N$), we investigated the water mass and the behavior of water column parameters such as dissolved oxygen, inorganic nutrients (N, P), and chlorophyll-a. Physico-chemical properties of water column were obtained by CTD system at the nine stations which were selected along the east-west and south-north direction around the seamount (OSM14-2) in October 2014. From the temperature-salinity diagram, the main water masses were separated into North Pacific Tropical Water and Thermocline Water in the surface layer, North Pacific Intermediate Water in the intermediate layer, and North Pacific Deep Water in the bottom layer, respectively. Oxygen minimum zone (OMZ, mean $O_2$ $73.26{\mu}M$), known as dysoxic condition ($O_2<90{\mu}M$), was distributed in the depth range of 700~1,200 m throughout the study area. Inorganic nutrients typified by nitrite + nitrate and phosphate showed the lowest concentration in the surface mixed layer and then gradually increased downward with representing the maximum concentration in the OMZ, with lower N:P ratio (13.7), indicating that the nitrogen is regarded as limiting factor for primary production. Vertical distribution of water column parameters along the east-west and south-north station line around the seamount showed the effect of bottom water inflowing at around 500 m deep in the western and southern region, and concentrations of water column parameters in the bottom layer (below 2,500 m deep) of the western and southern region were differently distributed comparing to those of the other side regions (eastern and northern). The value of Excess N calculated from Redfield ratio (N:P=16:1) represented the negative value throughout the study area, which indicated the nitrogen sink dominant environments, and relative higher value of Excess N observed in the bottom layer of western and southern region. These observations suggest that the topographic features of a seamount influence the circulation of bottom current and its effects play a significant role in determining the behavior of water column environmental parameters.

Marine Environment and the Distribution of Phytoplankton Community in the Southwestern Sea of Korea in Summer 2005 (여름 한국서남해역의 해양환경과 식물플랑크톤 군집분포)

  • Yoon, Yang-Ho;Park, Jong-Sick;Park, Yeong-Gyun;Noh, Il-Hyeon
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.10 no.3
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    • pp.155-166
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    • 2007
  • We carried out a study on the marine environment, such as water temperature, salinity, density and chlorophyll ${\alpha}$, and the distribution of phytoplankton community, such as species composition, dominant species and standing crops in the Southwestern Sea of Korea during early summer 2005. According to the analysis of a T-S diagram, three characteristics of water masses were identified. We classified them into Korean and Chinese coastal water, the cold water and the oceanic water. The first was characterized by high temperature and low salinity in the surface layer influenced by river run offs from China and Korea, the second by low temperature and salinity in bottom layer originated from the bottom cold water of the Yellow Sea, and the third by high temperature and high salinity influenced by Tsushima warm currents. The internal discontinuous layer among them was formed at the intermediate depth (about $10{\sim}20\;m$ layer). And the thermal front appeared in the central parts between Tsushima warm currents and Korean and Chinese coastal waters in the Southwestern Sea of Korea. Chlorophyll ${\alpha}$ concentration was high values in the Korean coastal waters and sub-surface layers. But It was low concentration in the Tsushima warm currents regions. The $Chl-{\alpha}$ maximum layers appeared in the sub-surface layer below thermocline. The phytoplankton community in the surface and stratified layers was composed of a total of 40 species belonging to 26 genera. Dominant species were 2 diatoms, Paralia sulcata, Skeletonema costatum and a dinoflagellate, Scripsiella trochoidea. Standing crops of phytoplankton in the surface layer were very low with cell density ranging from 5 to $3.8\;{\times}\;10^3\;cells/L$. Diatoms were controlled by the expanded low salinity coastal waters of the low salinity with high concentrations of nutrients. Otherwise phytoflagellates were dominant in the high temperature regions where the Tsushima warm currents approches the Southwestern Sea of Korea in early summer.

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Description and Application of a Marine Microalga Auxenochlorella protothecoides Isolated from Ulleung-do (울릉도 거북바위 조수웅덩이에서 분리된 해양 미세조류 옥세노클로렐라 프로토테코이드 균주의 기술 및 응용)

  • Jang, Hyeong Seok;Kang, Nam Seon;Kim, Kyeong Mi;Jeon, Byung Hee;Park, Joon Sang;Hong, Ji Won
    • Journal of Life Science
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    • v.27 no.10
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    • pp.1152-1160
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    • 2017
  • A unicellular green alga was axenically isolated from a tidal pool on Ulleung-do, Korea. Morphological, molecular, and biochemical analyses revealed that the isolate belonged to Auxenochlorella protothecoides. The current study is the first record of this species in Korea. The microalgal strain was named as A. protothecoides MM0011 and its growth, lipid and pigment compositions, and biomass properties were investigated. The strain is able to thrive in a wide range of temperatures ($5{\sim}35^{\circ}C$) and to withstand up to 1.5 M NaCl. The results of GC/MS analysis showed that the isolate was rich in nutritionally important polyunsaturated fatty acids (PUFAs). Its major fatty acids were linoleic acid (27.6%) and ${\alpha}-linolenic$ acid (39.6%). Thus, this indigenous microalga has potential as an alternative source of ${\omega}3$ and ${\omega}6$ PUFAs, which currently come from fish and plant oils. Also, the HPLC analysis revealed that the value-added antioxidant, lutein, was biosynthesized as the accessory pigments by the microalga. A proximate analysis showed that the volatile matter content was 85.6% and an ultimate analysis indicated that the gross calorific value was $20.3MJ\;kg^{-1}$. Since 40.5% of total nitrogen and 27.9% of total phosphorus were removed from the medium, respectively, it also has potential as a feedstock for biofuel applications which could be coupled to wastewater treatment. In addition, the biomass may also serve as an excellent animal feed because of its high protein content (51.4%). Therefore, A. protothecoides MM0011 shows promise for application in production of microalgae-based biochemicals and as a biomass feedstock.

Culture and Art Policies of Korean government for Traditional Dancing Digital Contents (전통춤 디지털 콘텐츠에 관한 문화예술정책 연구)

  • Kim, Ji-Won;Rhyu, Ji-Sung
    • The Journal of the Korea Contents Association
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    • v.12 no.9
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    • pp.156-171
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    • 2012
  • It is the time of the Korean Wave booming throughout the world, placing Korean culture in the center of the world and its added value is unaccountable. At this prosperity, the preserving of the archetype of Korean dancing and digital contents making is becoming a task not only for the government but also for the private sector because culture industry has enormous added values. To achieve such goals, contents development is an urgent matter but establishing the value of the archetype of Korean traditional dancing must have priority. The public has to take an active role in rediscovering the values of traditional culture, and as the representative of Korean identity traditional dancing must be the object of a systematic art policy. This study will review the current status of 'digital contents program of the archetype of culture' for traditional dancing and will reconsider the modern value of preserving the archetype of culture to make a suggestion to the direction of culture art policies in the near future. The study acknowledged the lack of technical personnel majoring in the archetype of traditional dancing and the need of reviewing the credibility of historical research procedures. Even with the studies by industry-university collaboration and positioning of specialists, effective policies that will form the foundation for private firms to train personnels is in urgent need. In other words, training personnels, allocation of resource, securing funds, policies promoting collaboration between private and individual businesses, and the commercial recognition at private firms are still far from establishing. This is due to the fact that archetype of culture is not a business that creates revenue immediately, therefore the recognition of traditional dancing as an investable item by business-oriented firms or movements are difficult to find. To overcome such situation, software oriented policies that establish open communication and sharing with the public should be done at first rather than the quantity oriented hardware policies of contents development. Through this process the public can change the attitude on traditional dancing and traditional dancing could be newly recognized as a creative repository of culture and as public businesses giving birth to economic value.

Clinical Courses of Cavitary Lesions in Pulmonary Tuberculosis (폐결핵에서 공동성 병소의 임상적 경과)

  • Park, Seung-Kyu;Kweon, Eun-Soo;Song, Sun-Dae
    • Tuberculosis and Respiratory Diseases
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    • v.50 no.4
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    • pp.484-492
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    • 2001
  • Background : Pulmonary tuberculosis with a remaining cavitary lesion is considered to be a problem with the course of treatment. In particular, re-treatment cases tend to respond poorly to current anti-tuberculosis agents. Therefore the factors that are related with the poor closure of a cavitary lesion in pulmonary tuberculosis during treatment were evaluated. Methods : A retrospective review of the medical records and chest X -ray films of 68 patients who had chemotherapy for the pulmonary tuberculosis with cavitary lesions was made. All the patients had been followed up for more than 12 months at National Masan Tuberculosis Hospital as of Aug. 2000. Results : The male to female ratio was 3.9:1.72.4% of the patients were between 20 to 50 years of age. 66.2% of the cavitary lesions on the chest X-ray films were confined to the upper lung fields : 36.8% in the right upper lung field and 29.4% in the left upper lung field. 82.4% of the cavities were less than 40 mm in their size, and 83.8% were less than 6 mm thick. The cavitary lesions were closed in 48 cases and remained in 20 cases during a follow-up period of more than 12 months. The factors that are thought to affect to the outcomes of the cavities were age, past medication history, the number of unused drugs, and the number of sensitive drugs. Conclusion : In the treatment courses of pulmonary tuberculosis with cavitary lesions, the following factors are associated with less desirable outcome:an age over 45, a past medication history of more than 2 courses of treatment, The number of unused drugs not exceeding average 6 and the number of sensitive drugs not exceeding average 7.

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The Prognostic Value of the Seventh Day APACHE III Score in Medical Intensive Care Unit (내과계 중환자들의 예후 판정에 었어서 제 7병일 APACHE III 점수의 임상적 유용성)

  • Kim, Mi-Ok;Yun, Soo-Mi;Park, Eun-Joo;Sohn, Jang-Won;Yang, Seok-Chul;Yoon, Ho-Joo;Shin, Dong-Ho;Park, Sung-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.50 no.2
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    • pp.236-244
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    • 2001
  • Background : Most current research using prognostic scoring systems in critically ill patients have focused on prediction using the first intensive care unit (ICU) day data or daily updated data. Usually the mean ICU length of stay in Korea is longer than in the western world. Consequently, a more cost-effective and practical prognostic parameter is required. The principal aim of this study was to assess the prognostic value of the seventh day(7th day : the average mean ICU length of stay) APACHE III score in a medical intensive care unit. Methods : 241 medical ICU patients from July 1997 to April 1998 were enrolled. The 1st and 7th scores were measured by using the APACHE III scoring system and compared between survivors and non-survivors. Logistic regression analysis was performed to determine the relationship between the $1^{st}$ and $7^{th}$ APACHE III scores and the mortality risk. Results : 1 )The mean length of stay in the ICU was $10.3{\pm}13.8$ days. 2)The mean $1^{st}$ and $7^{th}$ day APACHE III scores were $59.7{\pm}30.9$ and $37.9{\pm}27.7$. 3) The mean $1^{st}$ day APACHE III score was significantly lower in survivors than in non- survivors($49.9{\pm}23.8$ vs $86.3{\pm}32.3$, P<0.0001). 4)The mean $7^{th}$ day APACHE III score was significantly lower in survivors than in non- survivors($30.1{\pm}18.5$ vs $80.1{\pm}30.4$, P<0.0001). 5)The odds ratios among the $1^{st}$ and $7^{th}$ day APACHE III scores and the mortality rate were 1.0507 and 1.0779 respectively. Conclusion : These results suggest that the seventh day APACHE III score is as useful in predicting the outcome as is such like the first day APACHE III score. Therefore, in comparison to the daily APACHE III score, measuring the $1^{st}$ and $7^{th}$ day APACHE III scores are also useful for predicting the prognosis of critically ill patients in terms of cost-effectiveness. It is suggested that the $7^{th}$ day APACHE III score is useful for predicting the clinical outcome.

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Expression of Estrogen and Progesterone Receptors in Non-small-cell Lung Cancer Tissue Using Tissue Microarray Method (조직 미세배열법을 이용한 비소세포 폐암 조직에서 에스트로겐과 프로게스테론 수용체 발현)

  • Han, Hye-Seung;Kim, Min-Ji;Cho, Jae-Hwa;Yoon, Yong-Han;Kwak, Seung-Min;Lee, Hong-Lyeol;Kim, Kwang-Ho;Ryu, Jeong-Seon
    • Tuberculosis and Respiratory Diseases
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    • v.58 no.1
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    • pp.54-58
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    • 2005
  • Background : To evaluate the role of estrogen and progesterone in the carcinogenesis of NSCLC, IHC studies for the expression of the receptors of estrogen and progesterone have been performed with inconsistent results. Recently the TMA method has been developed and has become recognized as a useful and rapid method for extensively analysing molecular markers at the gene and protein level. We have investigated their expressions in the tissue from NSCLC using the microarray method. Methods : The TMA construction was made with 70 formalinfixed, paraffin-embedded tissues of NSCLC. After heat-induced epitope retrieval, IHC staining on primary tissues of NSCLC was performed with the monoclonal antibodies, ER1D5 and PR1A6. Results : Our sample of 70 consisted of 74% men and 26% women. Of the patients, 49% were current smokers, 27% were non-smokers and 24% were former smokers. By histologic classification, 34 patients had squamous cell carcinoma, 24 had adenocarcinoma, 9 had adenosquamous cell carcinoma, and 3 had other carcinomas. No cancer cells were immunostained with these monoclonal antibodies in any primary tissues of NSCLC. Conclusions : No expression of neither of the two receptors was found in any of the lung cancer tissues. This suggests that adequate genetic variants for IHC staining need to be developed for NSCLC.