• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.25 no.2
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• pp.87-104
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• 1989

Recently, with the tendency of more lightening, high-strength and high-speed in the marine industries such as marine structures, ships and chemical plants, the use of the aluminium Alloy is rapidly enlarge and there occurs much interest in the study of corrosion fatigue crack characteristics. In this paper, the initiation of surface crack and the propagation characteristics on the base metal and weld zone of 5086-H116 Aluminium Alloy Plate which is one of the Al-Mg serious alloy(A5000serious) used most when building the special vessels, were investigated by the plane bending corrosion fatigue under the environments of marine, air and applying cathodic protection. The effects of various specific resistances on the initiation, propagation behavior of corrosion fatigue crack and corrosion fatigue life in the base metal and heat affected zone were examined and its corrosion sensitivity was quantitatively obtained. The effects of corrosion on the crack depth in relation to the uniform surface crack length were also investigated. Also, the structural, mechanical and electro-chemical characteristics of the metal at the weld zone were inspected to verify the reasons of crack propagation behavior in the corrosion fatigue fracture. In addition, the effect of cathodic protection in the fracture surface of weld zone was examined fractographically by Scanning Electron Microscope(S.E.M.). The main results obtained are as follows; (1) The initial corrosion fatigue crack sensitibity under specific resistance of 25Ω.cm% show 2.22 in the base metal and 19.6 in the HEZ, and the sensitivity decreases as specific resistance increases (2) By removing reinforcement of weldment, the initiation and propagation of corrosion crack in the HAZ are delayed, and corrosion fatigue life increases. (3) As specific resistance decreases, the sensitivity difference of corrosion fatigue life in the base metal and HAZ is more susceptible than that of intial corrosion fatigue crack. (4) Experimental constant, m(Paris' rule) in the marine environment is in the range of about 3.69 to 4.26, and as specific resistance increases, thje magnitude of experimental constant, also increases and the effect by corrosion decreases. (5) Comparing surface crack length with crack depth, the crack depth toward the thickness of specimen in air is more deeply propagated than that in corrosion environment. (6) The propagation particulars of corrosion fatigue crack for HAZ under initial stress intensity factor range of $\Delta$k sub(li) =27.2kgf.mm super(-3/2) and stress ratio of R=0 shows the retardative phenomenon of crack propagation by the plastic deformation at crack tip. (7) Number of stress cycles to corrosion fatigue crack initiation of the base metal and the welding heat affected zone are delayed by the cathodic protection under the natural sea water. The cathodic protection effect for corrosion fatigue crack initiation is eminent when the protection potential is -1100 mV(SCE). (8) When the protection potential E=-1100 mV(SCE), the corrosion fatigue crack propagation of welding heat affected zone is more rapid than that of the case without protection, because of the microfissure caused by welding heat cycle.

• Korean Journal of Medicinal Crop Science
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• v.8 no.2
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• pp.102-108
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• 2000

Morphological characteristics of nine Epimedium spp was analyzed on the basis of six morphological characters. To analyse the genetic relationship among Epimedium spp., polymerase chain reaction (PCR) was performed with total genomic DNA of 17 Epimedium spp. by using random 8 primers. The genetic diversity and genetic distance among nine Korean collections, seven Japanese and one China collection were used to generate a dendrogram showing phylogenie relationship. Seventeen Epimedium spp were classified into two groups of group I and II, since they were divided into two major groups at the similarity coefficients value of 0.65. In addition, one of the two group, group I was divided into three sub-groups including Epimedium koreanum, Chul-won collections 1, 2, and 3, Yanggu, Hongchon, Hwachun, Chunchon, China, Maehwa (Japanese), E. diphyllum and E. violaceum (Japanese), while group II included Chulwon collection 4 and 5 and Japanese collection. The samples collected at Chulwon district showed close similarity with Japanese collection. Similarity indexes between collection and genetic relationship were related at the levels ranging from 0.6 to 0.9.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.1
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• pp.97-108
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• 2016

The competition between countries became internationalized in the market. However, a situation in which globalization is concerned is important to domestic corporates. Corporate strategy to survive in the domestic market are also juggling the limit of survival. Technology transfer and commercialization at this point has important implications now. The same applies to the national level. Public-to-private technology transfer has been more important, in order to overcome the international competitions. Although various studies have been made to promote technology transfer, in the livestock sector rarely attempted. Taking into account that few previous research and theory development has been achieved, the paper explored the technology transfer phenomenon in the sector employing the grounded theory approach by Strauss & Corbin(1998). Corporates that licensed in technologies through the Foundation of Agri. Tech. Commercialization & Transfer, were targeted as informants or interviewees. Finally, eight informants were selected sequentially utilizing theoretical sampling technique to the saturation point. As the result of open coding and axial coding of the interview data using NVivo10 by QSR International, 77 concepts, 20 sub-categories, and 7 categories were derived while paradigm model was established. Through selective coding, 'the factors affecting technology transfer in livestock sector' was identified as core category. The story line about the core category was developed based on four main categories. Finally, it is expected that the concepts, categories, and the relationship between them can be an important basis for further research.

• The Journal of Engineering Geology
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• v.11 no.1
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• pp.63-79
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• 2001

This study is aimed for estimating hydraulic parameters using the Cooper-Bredehoeft-Papadopulos, the Hvorslev, and the Bouwer & Rice methods at nineteen test holes in Me. Geumjeong area composed of Bulguksa granites, and for characterizing hydraulic properties at the test holes with relatioll to drill core data. The relation among hydraulic Dammeters obtained by the three methods is also considered. The study area is divided into four sub-areas to consider the hydraulic characteristics. The difference of hydraulic conductivity estimates between the injection and the withdrawal slug test may be due to penncable fracture distlibutions around the test hole and/or the disturbance of fine mateIials in the fractures induced by the pressure variation due to different mechanisms of test initiation. The hydraulic conductivity estimates detennined by the Cooper-Bredehoeft-Papadopulos, the Hvorslev and the Bouwer & Rice methods ranges from 10$^{-8}$ to lO$^{-5}$m/sec, and the ranges of average values are from 10$^{-7}$ to 10$^{-6}$m/sec. Also, the transmissivity ranges from 10$^{-7}$ to 10$^{-5}$$m^2$/sec. Comparing average hydraulic conductivity by the Cooper-Bredehoeft-Papadopulos, the Hvorslev and the Bouwer & Rice methods, by the Hvorslev method has the highest values, then the Bouwer & Rice method, and the Cooper-Bredehoeft-Papadopulos method has the lowest.

• Korean Journal of Ecology and Environment
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• v.43 no.3
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• pp.349-355
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• 2010

This study aims at the augmentation of reliability of the long-term rainfall runoff model. To do so agricultural water uses are evaluated by analyzing the effects of small scale irrigational hydraulic structures on long term runoff processes and thereby rainfall-runoff model is modified considering them. As a result the simulation results of the sub-basins having more agricultural reservoirs than the others are disagreed with the observations. The 2nd quarter simulation results show similar trend to it. Especially the farming seasonal results of the drought year as the year of 2008 have many negative discharge values due to the lack of agricultural water uses. This result come from the water uses input data corresponding to not real water uses but water demands. In this study the formulas are derived to estimate the discharges and return ratios and the long term rainfall-runoff model is reformulated based on these. It is confirmed that the errors of the simulation results could be reduced by considering the effects of small scale irrigational hydraulic structures and the reliability of the simulation results improved greatly.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.2
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• pp.168-178
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• 1983

Influence of several dehydration treatments on original structure and water behavior in the process of drying were investigated employing three hawaiian volcanic ash soils and four synthetic minerals. These three soils were developed under different rainfall condition and contained three different amount of amorphous materials in them. Measurement of water losses by oven drying at $105^{\circ}C$, $P_2O_5$ drying, freeze drying, and critical point drying revealed that more water losses were noted by oven drying than by three other drying techniques and the differences of water losses between oven and $P_2O_5$-drying were closely related to amoun: of amorphous materials in them, showing the order of Kaiwiki > Hilo > Kawaihae. This indicates that dehydration of amorphous materials by elevated temperature ($105^{\circ}C$) excluded water beyond that in the adsorbed (hygroscopic) state. The effect of dehydration treatments on initial structure was visualized by scanning electron microscopy. The micrographs showed that oven-and $P_2O_5$-dried samples formed into large mass of sub-angular blocky, dense, and closed crumbs, while the freeze dried and critical point dried samples resulted in less shrinkage, and small, fluffy and open spongy structure. However, critical point drying technique produced bulkier, softer, and greater open structure samples than even freeze drying. Additional Index Words: original structure, synthetic minerals, critical point drying, $P_2O_5$ drying. 1. This is a part of author's Ph.D. dissertation submitted to the University of Hawaii, Honolulu, Hawaii 96822 in 1979. 2. Professor of Agricultural Chemistry, Korea University.

• Journal of Preventive Medicine and Public Health
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• v.31 no.3 s.62
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• pp.395-403
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• 1998

To estimate the incidence rate of coronary heart disease in Korea, of all residents in Taegu city aged 25 or above, those who had an acute MI or a fatal coronary event between 1 July 1996 and 30 June 1997 were registered. Seven hundreds and eight patients were registered during the study period(685 were identified at hospital and 23 were autopsy cases). Age-standardized annual incidence rate of men in city area was 93 per 100,000(95% CI; 61-142) and 35% CI; 16-67) in women(100 in men and 20 in women aged 35-64). The incidence was rapidly increased after age 40 in men, however, in women after age 60. Twenty-eight-days case fatality rate was 45% in men and 47% in women. However, in the age group of 45-59 case fatality rate in women was two times higher than that in men. In conclusion, crude annual incidence rate of CHD in city area was 73 per 100,000 in men and 33 in women. The age-standardized annual incidence of CHD in men(93 per 100,000) was 2 times higher than that in women (33 per 100,000) in Korea.

• Management & Information Systems Review
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• v.28 no.4
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• pp.1-26
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• 2009

Among food-service managers, a survey was conducted to grasp the their work-related education conditions and the demand for education program development. This study focuses on food-service managers in web-based training and analyzes the critical factors involved in their learning process in order to clarify the factors that lead to the maximization of training programs. The results of all this study process are as follows. First, the characteristics of web-based education including component of education factor, system factor, deepening learning factor have meaningful effect on commitment of the participants and education performance(except deepening learning factor to education performance). Second, the analysis that the characteristics of individuals including self-efficacy in learning, purpose-directivity factor have meaningful effects on commitment of the participants and education performance(except purpose-directivity factor to education performance). Third, commitment of the participants has meaningful effects on the education performance. Thus, it is advisable for education managers or operators to emphasize in foodservice organizations.

• Journal of Oriental Medical Thermology
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• v.6 no.1
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• pp.49-55
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• 2008

Purpose: During Postpartum period many women complain multiple pain, cold hypersensitivity, hot flush, sweating and so on. We call the postpartum disease as San Hu Pung. We studied characters of DITI Characters of women suffering from Postpartum disease. Methods: We studied 55 patients visiting OOhospital from February 2006 to November 2007. The subjects were categorized in two groups, symptom group(37) and no symptom group(18). We measured the temperatures of abdomen(CV17, CV12, CV4), upper and lower limb(PC8, LU4, LR3, ST32) and back(GB21, BL18, BL53). We studied the difference of DITI between two groups by Student T-test using SPSS for windows (version 12.0). Results: The general characteristics such as age, days of postpartum, primiparity, cesarean section, partum season, breast-feeding of two groups were not different statistically. Temperatures of abdomen(CV17, CV12, CV4) and back(GB21, BL18, BL53) of two groups were not different statistically. Temperatures of Lt. PC8 and both LR3 of symptom group were statistically higher than no symptom group. The difference between Lt. PC8 and LU4, both LR3 and ST32 of symptom group were statistically higher than no symptom group. Conclusion: The results suggest that women suffering from Postpartum disease shows high temperature on hand and foot. It seems that postpartum disease patients tend to have blood deficiency. DITI can be useful to diagnose San Hu Pung. The more studies to diagnose San Hu Pung would be needed.

• Korean Journal of Environmental Agriculture
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• v.16 no.1
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• pp.55-60
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• 1997

Heavy metal-tolerant microorganisms, such as Pseudomonas putida, P. aeruginosa, P. chlororaphis and P. stutzeri which possessed the ability to accumulate cadmium, lead, zinc and copper, respectively, were isolated from industrial wastewaters and mine wastewaters polluted with various heavy metals. The distribution of heavy metal in the cell components, and amino acid compositions, was investigated. The distribution of heavy metal in the cell fractions of each heavy metal-tolerant microorganism grown for 20 hours in the basal medium containing 100mg/l of each heavy metal was investigated. In the case of cadmium-tolerant P. putida, lead-tolerant P. aeruginosa and copper-tolerant P. stutzeri, approximately $50{\sim}60%,\;30{\sim}40%$ and $10{\sim}17%$ of each heavy metal absorbed were distributed to cell wall, cell membrane and cytoplasm fractions, respectively. In the case of zinc-tolerant P. chlororaphis, approximately 32%, 55% and 13% of zinc were distributed to cell wall, cell membrane and cytoplasm fractions, respectively. These results indicated that the cell wall was a major adsorbing fraction of cadmium, lead and copper, and the cell membrane was that of zinc. Total amino acid content per gram of the cell grown in the culture media with heavy metal was higher than that of the cell grown in the culture media without heavy metal, and the content of acidic amino acids, such as aspartic acid(Asp.+Asn.) and glutamic acid(Glu.+Gln.) was higher than that of basic amino acids, such as histidine, lysine and arginine.