• Journal of Aquaculture
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• v.6 no.4
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• pp.235-253
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• 1993

The freshwater crab, Eriocheir japonicus inhabits from sub-tropical to temperate zone in Asia. This species belongs to a large size group among freshwater crabs. Common size of this crab is 5-6cm in carapace length and occasionally 7cm in carapace length. This species of crab used to inhabit in estuaries, rivers and inland waters in Korea. However, natural population recently has been rapidly decreased because of pollution and lost their habitats by suburban development. Therefore, development of proper methods of seedling production to increase natural stock became necessity. As parts of achieving this goal, duration from mating to spawning, egg incubation period, and egg development of this species were studied. The influence of temperatures and salinities on the egg incubation and hatching was also investigated. It took 2-8 hours from mating to egg spawning and the spawning lasted 3-9 hours from the first spawning. Egg numbers per female (6cm in carapace length) were 380,000­410,000. Optimum temperature for egg incubation was $17\~23^{\circ}C$ and optimum salinity, $14.0\~31.5\%o$. Incubation period of the eggs at $14^{\circ}C,\;17^{\circ}C,\;20^{\circ}C,\;26^{\circ}C,\;and\;28^{\circ}C$ was 42, 28, 21, 15, and 14 days. respectively. Relation between temperature (X) and incubation days (Y) was LogY = Log 2764.267 - 1.608 LogX. A female can spawn 4-6 times per year by manipulation of environmental conditions. Under the conditions of $18^{\circ}C\;and\;24.5\%o$, it took 6 days up to embryo formation, 18 days up to compound eye formation, 22 days up to abdominal movement, and 25 days up to hatch out as zoea larvae.

• Korean journal of food and cookery science
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• v.26 no.4
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• pp.367-380
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• 2010

Various contents of Rosa rugosa Thunb. fruit(0, 10, 20%), which is grown along the seashore of Gangwon province, were applied to apple jams having different sugar concentrations(20, 40, 60%). The resulting jams were analyzed using a sensory scoring test as well as a response surface methodology to identify the optimum conditions for the preparation of high-preference apple jams. The sensory properties based on sense of sight, smell and taste appeared to be linked to the sugar contents. It could be attributed to the presence of flavor compounds and pigments generated from the caramelization of sugar molecules during heat processing. On the other hand, rheological properties such as viscosity and spreadability were associated with Rosa rugosa fruit content, which was also verified by textural analysis of the jams. As the contents of Rosa rugosa increased, the hardness, gumminess, and chewiness of the jams decreased, which eventually might have contributed to the less thick and thus more spreadable sensory characteristics. Sensory evaluation revealed that apple jams were preferred when prepared with $\leq$10% of Rosa rugosa fruit and $\geq$55% of sugar contents. In particular, apple jams containing 10% Rosa rugosa and 60% sugar showed better mechanical qualities as well as higher sensory preference among 10 jams formulated using central composite design.

• Journal of Chest Surgery
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• v.34 no.6
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• pp.485-489
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• 2001

Background: The most important factor in preventing sternal complications is stable sternal approximation. We have tried to find the most effective sternal closure method by examining the incidence of sternal dehiscence with or without infection in patients with cardiac surgery through median sternotomy. Material and Method: This study was performed in 489 patients over 45 years of age with median sternotomy for open cardiac surgery. Simple closure with interrupted 6 wires was performed in 159 patients, figure-of-8 closure technique in 119, overlapping interrupted closure using 10 wires in 150, and combined closure technique of interrupted simple closure and figure-of-8 suture closure in 61. Two hundred thirty-four patients underwent valve and aortic operations and 213 patients coronary artery bypass surgery. Result: Sternal dehiscence with or without infection occurred in 12 (2.5 %) patients. The complication developed in 5 of 159 patients (3.1%) with six interrupted simple closure, in 4 of 119 patients (3.4%) with figure-of-8 closure, and in 3 of 150 patients (2.0%) with overlapping interrupted closure using 10 wires, but there was no complication in 61 patients with combined closure technique (relative risk for other closure techniques, p<0.05). There was no significant difference in the incidence of the sternal complication between valve and aortic operation group and coronary artery bypass group (3.0% vs 2.3%, not significant), but diabetes mellitus was a significant independent risk factor (odds ratio and multivariate analysis, p<0.05). Conclusion: The sternal closure technique that combines simple interrupted suture closure and figure-of-8 suture closure may be a more useful technique to enhance sternal stabilization compared to other closure techniques, such as simple interrupted closure, 8-figure closure, and overlapping interrupted closure.

• The Korean Journal of Nuclear Medicine
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• v.36 no.6
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• pp.368-380
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• 2002

Purpose: Liver transplantation (LT), one of the therapeutic options of primary liver cancer has been suffering from recurrence caused by metastasis in 8-54% of patients. This study was performed to investigate whether FDG-PET is useful for detecting hidden metastasis in LT candidates. Materials and Methods: Twenty-six patients (male:female=23:3, mean age 55.7 years) underwent FDG-PET. Their previous conventional diagnostic studies (CDS) like abdomen US and CT, chest x-ray and CT, and bone scan were negative (n=22) or equivocal (n=4) for metastasis. Positive FDG-PET findings were confirmed by biopsy or clinical follow-up. Results: Among 4 patients with equivocal metastatic lesions on CDS, 3 had 6 hypermetabolic lesions on FDG-PET, which were confirmed as metastasis and subsequently LTs were cancelled. Of these, 5 lesions were initially negative on CDS. Remained 1 patient underwent LT with a negative FDG-PET result. Among 22 patients without metastasis on CDS, 5 had 7 hypermetabolic lesions on FDG-PET. One of these patients proved to have 2 metastatic lesions, and LT was cancelled. The other 4 patients had S hypermetabolic lesions on FDG-PET, which were confirmed as benign lesions, and 3 patients of them underwent LT. In summary, FDG-PET was useful in avoiding 4 unwarranted LT by detecting unsuspected metastatic lesions on CDS. A total of 17 patients underwent LT. In comparison with pathology, the sensitivity and specificity of FDG-PET for detecting viable primary liver cancer were 55.6% (5/9) and 87.5% (7/8), respectively. Conclusion: FDG-PET can detect additional hidden metastasis and contribute to reducing unwarranted LT in the patients with primary liver cancer.

• Korean Journal of Organic Agriculture
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• v.26 no.1
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• pp.99-128
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• 2018

The cultivation area of rice as staple grains is decreasing in the domestic situation in Korea. Import volume of a duty in foreign rice is 409,000 tons for a year regardless increasing of production per unit area and decreasing of rice consumption. The total stock of rice is increasing cumulatively despite the effort for production mediation of rice. Therefore, maintenance of cultivation area and reduction of production are necessary for national foodstuffs security problems. Development of environment-friendly and low-carbon technology as alternative of global warming and aging of farm labor power is very important responsibility for descendants with creation of sustainable agriculture environment. As alternative for demand and supply stabilization of rice from all angles, first stage: extension of environment-friendly cultivation area as 17% Jeollanam-do level with maintenance of cultivation area under the present circumstances, second stage: extension of environment-friendly cultivation area as 25%, third stage: extension of environment-friendly cultivation area as 35%. From above mentioned scenario, reduction of rice production (60,000 tons), increases of production cost (59,200,000,000 Won), and reduction of income (201,500,000,000 Won) are estimated in first stage. Reduction of rice production (90,000 tons), increases of production cost (122,100,000,000 Won), and reduction of income (313,700,000,000 Won) are estimated in second stage. Reduction of rice production (380,000 tons), increases of production cost (222,000,000,000 Won), and reduction of income (464,500,000,000 Won) are estimated in third stage. From analysis results for partial tillage in transplanting cultivation complex (10ha), rice production is decreased 1.3~1.5 ton by complex. Production cost of rice is decreased and increases of income cultivation type. Gradual extension of environment-friendly agriculture and low-carbon partial tillage could be expected for environment maintenance of the territorial integrity, confidence of consumer, and high-efficiency of low-cost.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.2
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• pp.78-93
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• 2003

To investigate seasonal variation and structure of the microbial community in Kyeonggi Bay, abundance and carbon biomass of nano-and micrzooplankton were evaluated in relation to size fractionated chlorophyll-a concentration, through the monthly interval sampling from December 1997 to November 1998. Communities of nano-and microzooplankton were classified into 4 groups such as heterotrophic nanoflagellate(HNF), ciliates, heterotrophic dinoflagellates(HDF) and zooplankton nauplii. Abundance and carbon biomass of HNF ranged from 380 to 4,370 cells ml-1(average 1,340$\pm$130 cells ml-1) and from 0.63 to 12.4 $\mu\textrm{g}$C 1-1(average 4.35$\pm$0.58 $\mu\textrm{g}$C 1-1), respectively. Abundance and carbon biomass of ciliates ranged from 331 to 44,571 cells ml-1(average 3,526$\pm$544 cells ml-1) and from 1.3 to 119.7 $\mu\textrm{g}$C 1-1(average 13.7$\pm$3.0 $\mu\textrm{g}$C 1-1), respectively. Abundance and carbon biomass of HDF ranged from 88 to 48,461 cells 1-1(average 9,034$\pm$2,347 cells 1-1) and from 0.05 to 54.05 $\mu\textrm{g}$C 1-1(average 6.9$\pm$2.4 $\mu\textrm{g}$C 1-1), respectively. Abundance and carbon biomass of zooplankton nauplii ranged from 5 to 546 indiv. 1-1(average 83$\pm$15 indiv. 1-1) and from 0.17 to 43.2 $\mu\textrm{g}$C 1-1(average 6.3$\pm$1.2 $\mu\textrm{g}$C 1-1), respectively. Eash component of microbial biomass was not different from tidal cycle except tintinnids group. Depth integrated nano-and microzooplankton biomass ranged from 124 to 1,635 mgC m-2(average 585$\pm$110 mgC m-2) and was highest in March and May. The relative contribution of each component to the nano-and microzooplankton showed difference according to seasons. Community structure of nano-and microzooplankton was dominated by planktonic ciliate group. During the study period, carbon biomass of nano-and microzooplankton was strongly positively correlated with size fractionated chlorophylla-a. It implied that prey-predator relationship between microzooplankton and phytoplankton was important in the pelagic ecosystem of Kyeonggi Bay.

• Economic and Environmental Geology
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• v.54 no.5
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• pp.581-594
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• 2021

In 2020, about 132 million m³ of aggregate was produced in Korea. Of the total domestic aggregates produced in 2020, about 33.3 % was sand and about 66.7% was gravel. It estimated that of the 132 million m³ of aggregates in Korea in 2020, about 52% was produced by screening crushed aggregate, by 36% by forest aggregate, 3% by land aggregate, 5.6% by sea aggregate and 2.5% by washing each other, and 0.4% by river aggregate. This indicates that screening crushed aggregate and forest aggregate are the main producers of domestic aggregates. Leading producing metropolitan cities were Gyeonggi-do, Gyeongsangnam-do, Chungcheongbuk-do, Gangwon-do, Chungcheongnam-do, Incheon in order decreasing volume, which together accounted for about 72.4% of total product. In 2020, aggregates were produced in 153 cities, about 67% of the 231 cities of Korea, 38 local governments have developed aggregates of more than 1 million m³, and the combined production of the 38 cities accounted for about 65% of national total. This means that the aggregate extraction trend of local governments is becoming larger and more concentrated. In 2020, at 153 local governments, a total of 889 operations produced aggregates with 420 operations by permission, 469 operations by declaration. A review of production by size of operation indicated that about 17 million m³ (12.8% of the total aggregate) was produced by 14 operations reporting production of more than 1 million m³. In about 420 operations, the maximum period of permit is 32 years to at least 2 months. When the remaining period of permit is taken into account, only about 55% of active operations can be developed the aggregate after 2021. In order to maintain the permitted aggregate volume by 2020 level, it will be necessary to obtain an extension permit or find new operation sites for at least 200 or more operations.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.2
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• pp.70-88
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• 2019

A statistical analysis of 4,380 non-glutinous landrace rice germplasm collected from four East Asian countries namely South Korea (1,032), North Korea (994), Japan (800), and China (528) was conducted using normal distribution, variability index value (VIV), analysis of variation (ANOVA), and Duncan's multiple range test (DMRT) based on a data obtained from Near-Infrared Reflectance Spectroscopy (NIRS) analysis. In normal distribution, the average protein content was 8.2%, and the non-glutinous rice amylose, ranging over 10%, was found to be 22.0%. Protein content in most gremplasm was between 5.4 and 10.9%, and amylose content was between 15.0 and 28.9%. The VIV was 0.50 for protein, and 0.81 for non-glutinous rice amylose content. The average amylose content was 23.34% in Chinese, 21.55% in South Korean, 21.45% in Japanese, and 20.48% in North Korean resources, while the average protein content was found to be 9.02% in Chinese, 8.06% in Japanese, 8.04% in North Korean, and 7.99% in South Korean resources. ANOVA of amylose and protein content showed significant differences at p=0.01. The F-test value for amylose content was 94.92, and for protein content was 81.82 compared to the critical value of 3.79. DMRT of amylose and protein content revealed significant differences (p<0.01). Among the various germplasm obtained from different countries, that from North Korean had the lowest level of amylose content, whereas that from South Korea had the lowest level of protein content than all other resources. Chinese resources had the highest level of amylose and protein content. It is recommended to use these results in breeding fields.

• Proceedings of the Safety Management and Science Conference
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• 2004.11a
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• pp.355-380
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• 2004

I test the hypothesis that the gradual diffusion of information across asset markets leads to cross-asset return predictability in Korea. Using thirty-six industry portfolios and the broad market index as our test assets, I establish several key results. First, a number of industries such as semiconductor, electronics, metal, and petroleum lead the stock market by up to one month. In contrast, the market, which is widely followed, only leads a few industries. Importantly, an industry's ability to lead the market is correlated with its propensity to forecast various indicators of economic activity such as industrial production growth. Consistent with our hypothesis, these findings indicate that the market reacts with a delay to information in industry returns about its fundamentals because information diffuses only gradually across asset markets. Traditional theories of asset pricing assume that investors have unlimited information-processing capacity. However, this assumption does not hold for many traders, even the most sophisticated ones. Many economists recognize that investors are better characterized as being only boundedly rational(see Shiller(2000), Sims(2201)). Even from casual observation, few traders can pay attention to all sources of information much less understand their impact on the prices of assets that they trade. Indeed, a large literature in psychology documents the extent to which even attention is a precious cognitive resource(see, eg., Kahneman(1973), Nisbett and Ross(1980), Fiske and Taylor(1991)). A number of papers have explored the implications of limited information- processing capacity for asset prices. I will review this literature in Section II. For instance, Merton(1987) develops a static model of multiple stocks in which investors only have information about a limited number of stocks and only trade those that they have information about. Related models of limited market participation include brennan(1975) and Allen and Gale(1994). As a result, stocks that are less recognized by investors have a smaller investor base(neglected stocks) and trade at a greater discount because of limited risk sharing. More recently, Hong and Stein(1999) develop a dynamic model of a single asset in which information gradually diffuses across the investment public and investors are unable to perform the rational expectations trick of extracting information from prices. Hong and Stein(1999). My hypothesis is that the gradual diffusion of information across asset markets leads to cross-asset return predictability. This hypothesis relies on two key assumptions. The first is that valuable information that originates in one asset reaches investors in other markets only with a lag, i.e. news travels slowly across markets. The second assumption is that because of limited information-processing capacity, many (though not necessarily all) investors may not pay attention or be able to extract the information from the asset prices of markets that they do not participate in. These two assumptions taken together leads to cross-asset return predictability. My hypothesis would appear to be a very plausible one for a few reasons. To begin with, as pointed out by Merton(1987) and the subsequent literature on segmented markets and limited market participation, few investors trade all assets. Put another way, limited participation is a pervasive feature of financial markets. Indeed, even among equity money managers, there is specialization along industries such as sector or market timing funds. Some reasons for this limited market participation include tax, regulatory or liquidity constraints. More plausibly, investors have to specialize because they have their hands full trying to understand the markets that they do participate in

• Korean Journal of Poultry Science
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• v.35 no.4
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• pp.375-380
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• 2009

This study was conducted to investigate the effect of feeding induced molting on the visceral organs and blood component profile in laying hens and designed to test 400 flocks of 60 week old Leghorn laying hens for 34 weeks. A total of four molting treatment methods by including the molted with customary molting by fasting method (c), feeding single diet of corn (T1), feeding single diet of wheat bran (T2) and feeding single diet of alfalfa meal (T3) were tested, and each treatment was repeated for 5 times, and 20 laying hens were randomly assigned in an cage for each repeat. As the result of the experiment, ovary was $2.03{\sim}6%$ and oviduct was $2.51{\sim}3.47%$ in visceral organs for body weight at pre-molting term, but there was no significant difference. At post-molting, no significant difference was found, ovary was $0.25{\sim}0.41%$, uterus of control, T1, T2 and T3 was 1.12%, 0.82%, 0.48% and 0.90%, respectively. T2 was significantly lower than control, T3 (p<0.05) at the 50% of egg production. Ovary was $2.20{\sim}2.60%$ and oviduct was $2.98{\sim}3.45%$. In addition, ovary was $2.65{\sim}3.01%$, oviduct was $3.23{\sim}3.64%$ at the peak egg production, but there was no significant difference by non-feeding and feeding molting treatments. In blood component profile, cholesterol was $179.8{\sim}245.7\;mg/dL$ at pre-molting, but there was no significant difference and at post-molting, concentration of cholestrol in control, T1, T2 and T3 was 353.6, 229.1, 261.8 and 300.6 mg/dL, respectively. T1 was significantly lower than control and T3 (p<0.05). In addition, first laying day was $228.1{\sim}271.8\;mg/dL$, 50% of egg production was $236.5{\sim}284.8\;mg/dL$, there was no significant difference. Concentration of cholestrol in control, T1, T2 and T3 was 324.1, 591.6, 363.0 and 315.6 mg/dL, respectively, at the peak egg production period. T1 was significantly higher than other treatment (p<0.05).