• 한국잠사곤충학회지
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• 제17권1호
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• pp.1-26
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• 1975

These studies were attempted to find out the optimum silk reeling system by use of automatic silk reeling machine to increase raw silk yield and reeling efficiency with various silk reelable cocoons. The obtained results are as follows; 1. The mean silk reelability ratio(X)of the Korean cocoons during the last ten years was 61 per cent, beside 64.7 per cent in autumn cocoon and 57.3 per cent in spring cocoon. However, the ratio variation of autumn cocoons was larger than that of spring cocoons. 2. A positive correlation between cocoon filament breaks during its process and silk reelability levels was shown to be significant. The cocoons of both poor and good reelability evidenced "J" shape distribution on the filament break graph by the order of reeling cocoon end. Many bave breaks were found at the inner shell of the cocoons, or in case of poor reelability cocoons. 3. The morphology of broken cocoon ends during the process was classified into A, B, C, D, E and F types, The occurrence of B type was majority, but that of F type was minority among them. 4. In case of the cocoon cooking, H-type ion-exchanged soft water was better for good reelability cocoons, Na and H-type ion exchanged neutral soft water for those of fair reelability, and alkaline (Na-type) soft water for those of poor reelability, respectively. 5. The modification of cooking water by mixing the above different types of water (50％ Na-type and 50％ H-type passed by standard natural water; 75％ Na-type and 25％ H-type passed by hard natural water; 25％ Na-type and 75％ H-type passed by soluble natural water) made higher yield of raw silk with tess breaks of thread. 6, In case cocoon ends groping water included sodium hexametaphosphate as much as 800 ppm. the groping efficiency and raw silk yield of cocoon was improved. The effect was pronounced in case of poor reelability cordons. 7. The most reasonable cocoon cooking and silk reeling condition for automatic silk reeling process were observed to be rather incomplete cook with good reelability cocoons and optimum cook with poor reelability cocoons succeeded by the reeling bath temperature of 45$^{\circ}C$, 8. The reasonable silk reeling velocities were observed to be about 150m per min. for good reelability cocoons, 120m per min. for fair reelability ones and 90 to 120m per min. for poor reelability ones. 9. In order to improve the raw silk yield of cocoons and reeling efficiency, the cocoon stand-by-ratio for reeling should be kept at the level of 40 per cent for good reelability cocoons or at 60 per cent for poor reelability ones beside necessary end found cocoon condition.

• 수산경영론집
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• 제22권2호
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• pp.75-99
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• 1991

A quantitative analysis was carried out to monitor the commercial yield level of walleye pollock Theragra chalcogramma in the east coast of Korea, based on available data on catch and fishing effort, catch per unit of effort including fish prices from 1911 to 1988, using a traditional yield model. The results from the quantitative assessment were based to estimate maximum economic yield (MEY) and optimal fishing effort (E-opt) at MEY. On the other hand, interaction aspects between danish seine fishery and trawl fishery mainly targeting walleye pollock in the east coast of Korea were studied to predict optimal situation in fishing effort level from economic point of view which gives the most benefits to the two fisheries. Total production of walleye pollock in 1911 when its catch record was begun for the first time was about 12, 000 metric tons(M/T), and then the catch trend maintained nearly at the level of 50, 000 M/T per annum, showing a decreasing trend until 1930. The highest production from historical data base on walleye pollock fishery statistics was from the years in 1939 and 1940, about 270, 000 M/T and 26, 000 M/T, respectively. No production of the fish species was recorded during the years from 1943 to 1947, and from 1949 to 1951. From 1952 onwards annual production was only available from the southern part of 38$^{\circ}$N in the east coast. During two decades from 1952 to 1970, the production had sustained about less than 30, 000 M/T every year. Annual production showed an increasing trend from 1971, reaching a maximum level of approximately 162, 000 M/T in 1981. Afterwards, it has deceased sharply year after year and amounted to 180, 000 M/T in 1988. The catch composition of walleye pollock for different fishery segments during 1970~1988 showed that more than 70% of the total catch was from danish seine fishery until 1977 but from 1978 onwards, the catch proportion did not differ from one another, accounting for the nearly same proportion. Catch per unit of effort (CPUE) for both danish seine fishery and trawl fishery maintained a decline tendency after 1977 when the values of CPUE were at level of 800 kg/haul for the former fishery and 1, 300 kg/haul for the latter fishery, respectively. CPUEs of gillnet fishery during 1980~1983 increased to about 3.5 times as high value as in the years, 1970~1979 and during 1987~1988 it decreased again to the level of the years, 1970~1978. The bottom longline fishery's CPUE wa at a very low level (20 kg/basket) through the whole study years, with exception of the value (60 kg/basket) in 1980. Fishing grounds of walleye pollock in the east coast of Korea showed a very limited distribution range. Danish seine fishery concentrated fishing around the coastal areas of Sokcho and Jumunjin during January~February and October~December. Distributions of fishing grounds of trawl fishery were the areas along the coastal regions in the central part of the east coast. Gillnet and bottom longline fisheries fished walleye pollock mainly in the areas of around Sokcho and Jumunjin during January~February and December. Relationship between CPUEs' values from danish seine fishery and trawl fishery was used to standardize fishing effort to apply to surplus production model for estimating maximum sustainable yield (MSY) and optimum fish effort (F-opt) at MSY. The results suggested a MSY of 114, 000 M/T with an estimated F-opt of 173, 000 hauls per year. Based on the estimates of MSY and F-opt, MEY was estimated to be about 94, 000 M/T with a range of 81, 000 to 103, 000 M/T and E-opt 100, 000 hauls per year with a range of 80, 000 to 120, 000 hauls. The estimated values of MEY and E-opt corresponded to 82% of MSY and 58% of F-opt, respectively. An optimal situation in the fishing effort level, which can envisage either simultaneously maximum yield or maximum benefit for both danish seine fishery and trawl fishery, was determined from relationship between revenue and cost of running the fleet : the optimal fishing effort of danish seine fishery was about 52, 000 hauls per year, corresponding to 50 danish seiners and 27, 000 hauls per year which is equal nearly to 36 trawlers, respectively. It was anticipated that the net income from sustainable yield estimated from the respective optimal fishing effort of the two fisheries will be about 3, 800 million won for danish seine fishery and 1, 000 million won for trawl fishery.

• Journal of Microbiology and Biotechnology
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• 제4권2호
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• pp.126-133
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• 1994

A Pseudomonas putida strain able to accumulate high amount of polyesters of medium-chain-length 3-hydroxyalkanoic acids ($PHA_{MCL)$) was isolated from soil in a landfill site using an enrichment technique. Culture condition of the isolated strain for polyester production in a one-step culture was optimized in a mineral-salts medium against pH and concentrations of ammonium sulfate, carbon source(e.g., octanoate), and phosphate. The optimal values for maximal cell growth and PHA accumulation were: pH; 7$\sim$8, $(NH_4)_2SO_4$; 8 mM, octanoate; 40 mM. The optimum temperature was in the range of $20\sim30^{\circ}C$, which was rather broader than in other bacteria. Cell growth was strongly inhibited by the phosphate limitation to less than 1 mM. An increase of phosphate concentration above 1 mM showed little effect on cell growth and polyester accumulation. When the strain was grown on octanoate under this optimized condition it produced 3.4 g dry biomass per liter and yielded 1.7 g PHA per liter amounting to 53 wt% of dry cells. The monomer units composing the polyester synthesized from octanoate were 3-hydroxyoctanoate (3HO), 3-hydroxycaproate (3HC), and 3-hydroxybutyrate (3HB) (85:13:2, mole ratio). Other low linear $C_3\simC_{10}$ monocarboxylic acids were also tested for polyester production.

• Journal of Plant Biology
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• 제18권3호
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• pp.129-134
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• 1975

It was studied of relation between biomass of reed communities (Phragmitis communis) and several environmental factors concerned with such as chlor ine, pH, humus content in soil and depth of seawater submerged. Two sites where were the different geographical conditions were set up. One site had two plots: H plot, at theshallows of seawater, was not submerged except at full tide or at heavy rainfall, and M plot, at medium depth of seawater, submerged at every common tide at inside of a bank along the west seashore of Mu-An-peninsula. The other site also two plots: M' plot, at medium depth, submerged about 10 hours at each tide, and L plot, at deep seawater submerged every tims at tide at the outside of a bank along the eastside estuary of Youngsan river. Maximum standing crop of the reed community was shown on 25th of June: biomass at H M, M' and L plot were respectively 4.65, 3.60, 0.98, and 0.67 kg dry weight per $m^2$. Density of individual at H, M, M' and L plot was 67, 78, 244 and 333 plants per $m^2$. Net production of the terrestrial parts of rred community on the outside of the bank were lesser as much as a sixth than that on inside, but the density of the plant on outside of the bank was higher as much 4 or 5 times than that on inside. It was assumed that the growth of reed plant was inhibited by high chlorine, high pH, less humus in soil and submergence of seawater for long period.

• Bulletin of the Korean Chemical Society
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• 제18권9호
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• pp.929-933
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• 1997

Morphological studies in the micro-end-to-end (m-E-E) and micro-side-by-side (m-S-S) aggregations were conducted by using of scanning electron microscope (SEM) for the samples precipitated by heating of the end-products of the transition of FormⅡ (left-handed helix, three peptides per turn, 31) Form Ⅰ (right-handed helix, 3.3 peptides per turn, 103) in poly(L-proline) (PLP) in acetic acid(water)-propanol (1:9 v/v) solvent. The observed morphology for the solide state shows a rope (or super helical) type and pebbles type aggregate for the (m-E-E) and (m-S-S) aggregate respectively. The viscosities were also measured during the heat-precipitation in order to elucidate the process of formation of the rope- and pebbles-type aggregates. The result for the (m-E-E) aggregations exhibit two steps, i.e., at first, the viscosity increases with time (step 1), thereafter it decrease until attain the last value (step 2). But the (m-S-S) aggregations show only one step in the decreases in viscosity. On the bases of all experimental results it is possible to propose a reasonable mechanism for the formation of the two types of aggregates of the (m-E-E) and (m-S-S).

• Journal of Nutrition and Health
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• 제24권3호
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• pp.219-229
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• 1991

The longitudinal changes on human milk volume per day and lactational performance of 23 Korean lacto-ovo-vegetarians(primiparae=11, multiparae=12) from 0.5 to 5 months after parturition have been studied by test weighing method. The human milk volume per day tended to increase during lactation. The mean volume (SD, ml/day) at 0.5, 1, 2, 3, 4, 5 months were 502(102), 692(127), 697(100), 684( 125), 757(52), 703(70), respectively. The overall mean volume was 661$\pm$132ml/day. The peak milk volume during the lactation was observed at most lactating women at the 1st month. The distributions of the individual mean volume during the first 5 months of lactation were found over 750m1(8.7% ), 650-750ml(47.9% ), 550-650m1(2l.7% ), and 450-550ml(2l.7% ) The number of feeding per day was 8.1 ($\pm$1.0) at 0.5 months postpartum, which was consistently decreased. However, the mean volume per feeding was increased from 62($\pm$9.5)ml at 0.5 month to 112($\pm$13.3)ml at 5 months postpartum. The milk volume was correlated with the peak volume. and maternal age. but not with weight before delivery. maternal height and birth weight. No differences of milk volume and lactational performance between facto-ovo-vegetarian and nonvegetarian women were observed. This study suggests that the human milk volume cited in the recommended dietary allowances for Koreitns is over estimated.

• Asian-Australasian Journal of Animal Sciences
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• 제7권1호
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• pp.19-29
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• 1994

The annual income (gross margin) in 1989/90 of a sample of 274 farmers in seven milk cooperatives was analyzed in the sugar cane, cassava, and horticulture areas in East Java. On average dairying contributed 42%, crops 29% and off-farm revenue 29%. Dairy income was highest in the cassava area, where it compensated for the low crop income, and lowest in the sugar cane area. Farm area and average milk yield per day per cow correlated positively with farmer's income, whereas crop income increase significantly with farm area and with the number of cows. The level of total cost per cow had a negative impact on dairy and with the number of cows. The level of total cost per cow had a negative impact on dairy and on total income. Government officials and other professionals engaged in dairying had a significantly higher total income than those with their main occupation in dairying, cropping or working as farm labourers. Uneducated farmers obtained a significantly larger income through crops, whereas farmers with tertiary education obtained more income through off-farm work, This study suggests that more attention must be paid to the actual use of labour and the improvement of the dairy output/cost ratio.

• Asian-Australasian Journal of Animal Sciences
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• 제6권1호
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• pp.13-17
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• 1993

This study was conducted to determine the cost of production of semen and the rate of conception for artificial insemination in eight randomly selected districts of Bangladesh. A sample of 640 adopting farms were investigated. Results indicate that the cost of liquid semen per dose on full-cost and cash cast basis were Tk. 16.17 and Tk. 14.48, while the cost of locally produced exotic semen and imported semen were Tk. 31.25 and Tk. 110.00 respectively. The cost of liquid semen per insemination, per conception and per progeny on full-cost were Tk. 26.65, Tk. 50.64, and Tk. 56.27 respectively and on cash cost were Tk. 23.88, Tk. 45.37 and Tk. 50.41 respectively. The average cost of semen paid by the farmers was Tk. 14.00 and it was higher in urban areas than in rural areas. Out of the cost of A.I. centres, government had subsidized 92.16 percent and the rest 7.84 percent accrued as returns. About 40 percent of the produced semen was lost in the system which could not be used at all. The conception rate on first insemination was 53.6 percent. The rate increased to 73.2 percent upto the last insemination. The difference in conception rate between liquid semen (69.97%) and frozen semen (70.48%) was not statistically significant.

• 한국작물학회지
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• 제26권4호
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• pp.318-323
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• 1981

대두의 돌연변이육종을 함에 있어서 돌연변이기의 효율적인 선발법을 확립하기 위하여 M_1세대의 초장 및 주당종자수와 M_2세대의 돌연변이 출현과의 관계 그리고 M_1 식물체의 키메라에 대해 조사한 결과를 요약하면 다음과 같다. 1. 30kR의 감마선을 종자에 처리하였을 때 M_1초장의 분포는 무처리에 비해 45-68% 감소되는 개체가 전체의 63.7%를 차지하였으며 이 범위에 속하는 집단내에서 엽녹소변이는 71.4%, 가시적 형태변이가 62.3%를 차지하였다. 2. M_1주당종자수는 6-15개인 개체가 전체의 58.9%를 차지하였고 이때 엽녹소변이는 55.3%, 가시적 형태변이는 63.4%를 차지하였다. 3. M_1 집단에서 초장과 주당종자수는 통계적으로 유의한 정의 상관이 있었다. 4. M_1의 초장의 장해가 심하고 주당종자수가 적을 수록 M_2에서 가시적 형태변이의 출현율이 높았으며 반대로 엽녹소변이는 초장장해가 적고 주당종자수가 많을수록 변이출현율이 높은 경향이었다. 5. 변이가 일어난 M_2 family의 변이의 sector 크기는 M_1주당종자수 적을수록 크게 나타났다. 6. 엽녹소변이를 대상으로 M_1식물체의 꼬투리별로 돌연변이의 출리양상을 보면 식물체의 부위별로 일정한 경향이 없이 임의로 발생하였다. 7. 대두의 돌연변이육종을 효율적으로 수행하기 위해서는 종자에 고선량의 방사선을 처리할 것과 M_1의 주당종자수가 적은 개체를 수확하여 M_2에서 집단으로 양성할 것을 추천한다.

• 한국버섯학회지
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• 제3권4호
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• pp.154-158
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• 2005

참나무 톱밥에 3가지 첨가제 즉 미강, 밀기울, 콩비지가 부피 비율로 10, 20, 30% 첨가되었다. 다수확은 미강과 밀기울 20% 첨가시 그리고 콩비지 30% 첨가시 좋았다. 다양한 톱밥 재료 중 참나무 톱밥 단용 처리가 좋았고, 균배양 일수는 22일, 초발이 소요일수 11일, $1,200m{\ell}$ 병당 수량은 23.5g 수확되었다. 병의 크기에 따른 잡균 발생율은 $1,200m{\ell}$ 병이 5%로 가장 낮았다. 병 크기에 따른 생육특성에 있어, $1,600m{\ell}$ 병 재배시 초발이소요일수 13~15일, 자실체 생육일수 36~37일이고, 병당 수량은 26.7~29.3g이었다. 단위 면적당 최고의 수량은 평당 218병을 재배할 수 있는 수평식 균상에서 6.4kg으로 가장 높았다. 영지는 수평식 균상에서 $1,600m{\ell}$ 병재배시 갓의 수가 적고, 수량이 높아 가장 경제적이었다.