• Journal of Korean Society of Forest Science
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• v.95 no.2
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• pp.168-173
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• 2006

Stem respiration rate ($R_{stem}$) was examined using an open flow system on black locust (Robinia pseudoacacia L.). $R_{stem}$ exponentially increased with increasing air and stem temperature during measurement period and was most closely correlated with stem temperature. It was more closely correlated with stem temperature observed 0.5-2.0 hrs earlier than with current stem temperature, that is, there was time lag between the increase of stem temperature and the efflux of $CO_2$ from stem. $R_{stem}$ gradually increased from spring to summer, and then decreased during autumn. $R_{stem}$ ranged from 0.13 to $4.44{\mu}mol$ $CO_2m^{-2}s^{-1}$. $Q_{10}$ decreased with increasing stem temperature, and varied along position (or diameter) within trees during the same period, especially during the growing season. On the other hand, time lag was shortened with increasing temperature.

• Journal of the Korean Institute of Landscape Architecture
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• v.17 no.2
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• pp.27-39
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• 1989

The purpose of this study is to prove the factors affecting the fluctuation of daily visitors in five mountainous national park(Kayasan, kyeryongsan, Naejangsan, Soraksan, Songnisan), and to analyze the relationship between these factors and daily visitors in Korea. "Three Factors and Nine Categories"(Aoki, K. & Aoki, Y. : 1974, 1979) has been applied to this study, and statistical analysis method was carried out by computer program SAS and SPSS. The number of daily visitors is calculated based on the data of "Daily entrance ticket sale report" by administration office in each national park. The scope of time period is during the last 5years(1982∼1986: 1825days) and the results were as follows: 1) There were significant differences in the number of daily visitors of each national park among months, days of a week and weather-the same as the previous study of urban park case. But it wold be better for their category classification to be adjusted according to the fluctuation pattern of each national park. 2) The peak of monthly visitors comes in May(Kayasan, Soraksan, Songnisan) or October(Kyeryongsan, Naejangsan). These months are specified as group tour season. On the basis of monthly fluctuation pattern, Each national park were classified into seasonal type, that is, kayasan, Soraksan were proved to be three-season type(Spring, Summer, Autumn), Songnisan to be two-season type(Spring, Autumn), and Naejangsan to be one-season type(Autumn). 3) The weekly pattern differs from three category (weekday, weekend, holiday: Eom, Choi 1986) in the case of urban park study. And there is no significant difference in daily fluctuation pattern by weather (fine, cloudy and rainy day), but significant difference between snowy and the others. This result is due to the characteristics of visitors, which is, the major visits of national park are planned in a advance of the tour, therefore it is difficult to change the plan by the weather. 4) the result of correlation analysis showed that the most influential factor on national park use in Kayasan, Naejangsan, Soraksan and Songnisan is ′Monthly characters (M)′, on the contrary ′Day of week(D)′ in Kyeryongsan only. From the result, The more parks are resource-based, the more ′Monthly characters′-factor is supposed to affect the number of daily visitors rather than ′Day of the week′-factor. This means that kayasan, naejangsan, Sorakson and Songnisan are classified into resource-based type, but on the other hand Kyeryongsan should be classified into intermediate type.

• Journal of Sasang Constitutional Medicine
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• v.10 no.1
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• pp.253-267
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• 1998

'Maek(麥)' which means a barley at present is used as a general name of the kinds of 'Maek(麥)' including barley, what, rye, and so on. However 'Maek(麥)' had meant a wheat when the letter of 'Maek(麥)' had been created at the beginning. And gradually 'Maek(麥)' has been used as a word for the both meaning of a wheat and barley, and now a days become a word only for the meaning of a barley. Therefore 'Mo-Maek' should be translated into 'a wheat and barley', although it is translated into only a barley. In Korea, according to 'Nong-ga-wol-ryung(農家月令)' of Ko, Sang-un(高尙顔) in 1619, the vernalization had been utilized practically 300 years earlier than the Western countries. It is based on a concept of the oriental medicine that a 'Maek(麥)' of the spring seedtime, which keeps the only warmth('Won-yeol-ji-ki(溫熱之氣) (陽氣)' during the growth period in spring-summer time, has less vigorous than a 'Maek(麥)' of the autumn seedtime, which keeps the cold, hot, warmth equally 'Yeol-won-yang-han-ji-ki(溫熱凉寒之氣) (陽氣+陰氣)' during the growth period in the four seasons. If a autumn seedtime barley but which is actually not sowed on time in autumn season is sowed in the spring after the treatment of cold condition (陰氣 autumn-winter condition) artificially, it would be avoided from the abnormal phenomenon that a barley could not come to fruition in case of non-treated seed. Thus as a result of this the agricultural productivity has been able to be improved. An barley is recommended as a food for Um-chung-ji-ki(陰淸之氣) to be served as Bo-myung-ji-ju(保命之主) to be Soyangin. And a wheat which is used as an ingredient of bread because of its expanding feature is a suitable food for Ho-san-ji-ki(呼散之氣) to be served as Bo-myung-ji-ju(保命之主)to the Taeumin.

• Journal of the Korean Wood Science and Technology
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• v.16 no.4
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• pp.10-39
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• 1988

This study investigated the temperatures and relative humidities in the semi-greenhouse type solar dryer with a black rock-bed heat storage and without heat storage and outdoor temperature and relative humidity at 9 a.m. and 2 p.m.. A comparison was made of the drying rates, final moisture contents, moisture content distributions, casehardening stresses, drying defects, volumetric shrinkage of dried lumber for solar- and air-drying from the green condition of mixtures of Douglas-fir, lauan, taun, oak and sycamore 25mm- and 50 mm-thick lumber during the same period for four seasons, and heat efficiencies for solar dryer with and without the heat storage for saving of heat energy and the cost of lumber drying using the solar energy. The results from this study were summarized as follows: I. The mean weekly temperatures in the solar dryers were 3 to $6^{\circ}C$ at 9 a.m. and 9 to $13^{\circ}C$ at 2 p.m. higher than mean outdoor temperature during all the drying period. 2. The mean weekly relative humidities in the solar dryers were about 1 to 19% at 9 a.m. higher than the outdoor relative humidity. and the difference between indoor and outdoor relative humidity in the morning was greater than in the afternoon. 3. The temperatures and relative humidities in the solar dryer with and without the heat storage were nearly same. 4. The overall solar insolation during the spring months was highest and then was greater in the order of summer, atumm, and winter month. S. The initial rate of solar drying was more rapid than that of air drying. As moisture content decreased, solar drying rate became more rapid than that of air drying. The rates of solar drying with and without heat storage were nearly same. The drying rate of Douglas-fir was fastest and then faster in the order of sycamore, lauan, taun and oak. and the faster drying rate of species, the smaller differences of drying rates between thicknesses of lumber. The drying rates were fastest in the summer and slowest in the winter. The rates of solar drying during the spring were more slowly in the early stage and faster in the later stage than those during the autumn. 6. The final moisture contents were above 15% for 25mm-thick air dried and about 10% for solar dried lumber, but the mean final MCs for 50mm-thick lumber were much higher than those of thin lumber. The differences of final MC between upper and lower course of pile for solar drying were greater than those of pile for air drying. The differences of moisture content between the shell and the core of air dried lumbers were greater than those of solar dried lumber, smallest in the drying during summer and greatest in the drying during winter among seasons. 7. Casehardening stresses of 25mm- and 50mm-thick dried lumber were slight, casehardening stress of solar dried lumber was severer than that of air dried lumber and was similar between solar dried lumber with and without heat storage, Casehardening stresses of lumber dried during spring were slightest and then slighter in the order of summer, autumn, and winter. Casehardening stresses of Douglas -fir, sycamore and lauan were slight, comparing with those of taun and oak. 8. Maximum initial checks of 25mm-thick lumber occurred above and below fiber saturation point and those of 50mm-thick lumber occurred in the higher moisture content than thin lumber. As the moisture content decreased, most of checks were closed and didn't show distinct difference of the degree of checks among drying methods. The degree of checks were very slight in case of Douglas-fir and lauan, and severe in case of taun and oak. The degree of checks for 50mm-thick lumber were severer than those for 25mm-thick lumber. 9. The degree of warpage showed severe in case of oak and sycamore lumber, but no warping was found in case of Douglas-fir, lauan and taun. 10. The volumetric shrinkages of taun and oak were large and medium in case of Douglas-fir, lauan and sycamore. 11. Heat efficiencies of solar dryer with heat storage were 6.9% during spring, 7.7% during summer, 12.1% during autumn and 4.1% during winter season. Heat efficiency of solar dryer with heat storage was slightly greater than that of without heat storage. As moisture content of lumber decreased, heat efficiency decreased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.1
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• pp.65-72
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• 2004

Fish catch by a set net in Hamdeuk fishing ground off Jeju Island were studied to determine seasonal variation of species composition and catch from 1998 to 2000. A total 72,022.9 kg was caught during the survey period, including Scomber japonicus and Trachurus japonicus of $76.4\%$ in the total. The other dominant species were Siganus fuscescens, Loligo chinesis, Seriola dumerili, Sepioteuthis lessoniana, Sardinops melanostictus, and Seriola lalandi accounting to $20.0\%$ of the total. The fishing period conducted by a set net in Hamdeuk fishing ground were from May to November. The catch by a set net were higher in summer than in spring and autumn and closely related with the seasonal variation of sea water temperature. The catch was higher in 1998 than In 1999 and 2000, which was related to the sea water temperature in fishing ground.

• 한국해양학회지
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• v.30 no.5
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• pp.403-412
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• 1995

The present study was performed to determine th growth and production of Mactra veneriformis on the Songdo tidal flat off Inchon. west coast of Korea. Monthly samples were collected from Marc 1989 to September 1990. The size distributions of shell length showed unimodal patterns from March to August 1989. The binodal pattern after September 1989 indicated a recruitment of young clams during this period. The density fluctuated irregularly, but showed a decreasing pattern over time on the whole. The density of the year class 1989 increased markedly after February 1990. The growth in shell length showed three phases during a year, a fast growth phase in spring, a slow growth phase in summer and autumn, and a lag phase in winter. The annual increment in shell length reduced with age. The flesh dry weight showed a peak in late spring just before the spawning period, and another peak in autumn. The length of annuli and the back-calculated flesh dry weight were used to describe the annual growth. The growth in shell length fitted to the von Bertalanffy model and the flesh dry weight to the Gompertz model. The absolute growth rate of the shell length reduced gradually with age. The year class 1985 had the highest L, and the yeat class 1986 the lowest L. The annual growth in weight showed a typical sigmoid curve. The growth rate was maximum at the age of 2 to 3. Year classes of 1984 and 1985 had higher values of W and higher absolute growth rates than those of 1986 and 1987. Maximum absolute growth rates of 1986 and 1987 year classes were recorded at younger ages than 1984 and 1985 year classes. The annual relative growth rates of length and weight decreased exponentially with age. Biomass in flesh dry weight increased till spring and thereafter decreased progressively. Maximum biomass was 134.6g m/SUP -2/ in August 1990. The biomass of 1989 yeat class occupied highest proportion in total biomass. Annual production in flesh dry weight from March 1989 to March 1990 was 67.9 g m/SUP -2/ year/SUP -1/. Cumulative production of 1989 year class was highest among all year classes, and that of year class 1984 was lowest. The production is high in spring and autumn, and very low in summer and winter.

• Journal of Korean Society on Water Environment
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• v.33 no.6
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• pp.650-660
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• 2017

In this study, pollutant emission characteristics by water damage period analyzed 11 items (water temperature, pH, DO, EC, BOD, COD, TOC, SS, T-N, T-P and flow) with load duration curve, time series load curve and factor analysis for three years (2014-2016). Load duration curve is applied to judge the level of impaired waterbody and estimate impaired level by pollutants such as BOD and T-P in this study depending on variation of stream flow. Water quality standard exceeded the flow of mid-range and low-range by flow condition evaluation using load duration curve. This watershed was influenced by point source more than non-point source. Cumulative excess rate of BOD and T-P kept water quality standard for all seasons (spring, summer, autumn and winter) except BOD 59% in spring. Water quality changes were influenced by pollutants of basic environmental treatment facilities and agricultural areas during spring and summer. Results of factor analysis were classified commonly first factor (BOD, COD, and TOC) and second factor (flow, water temperature and SS). Therefore, effects of artificial pollutants and maintenance water must be controlled seasonally and reduced relative to water damage caused by point pollution sources with effluent standard strengthened in the target watershed.

• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.43-50
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• 1977

This stuy was conducted to analyse the variation in occurrance of fruit body of Agaricus bisporus (Lange) Sing, depending on difference of cultivation and harvesting method and to find out a method for early predicting the mushroom yield potential at the base of results of the analysis. The results obtained were as follows ; 1. Total mushroom yield was highly correlated with picking amount of fruit bodies during first 30 days of picking period, and yield potentiality in the certain high yielding mushroom house was markedly affected with the yield of middle and late period of picking. 2. Variation of mushroom yield with varying the degree of maturity of fruit bodies appeared to be different between spring and autumn cropping : in case autumn cropping was usally undertaken with normal cropping scheme, mushroom yield showed a reduction in early period of picking but an increase in late period when the mushrooms where picked at pre-matured stage. 3. When the picking rate of button form was laid in the range of 20~45%, and increase of total mushroom yield was accompanied by an increasing tendency of picking rate of button form. 4. Cropping results from mushroom houses could be early predicted from the regression equations, which was based on the analysis of variation in fruit body occurance throughout the picking period.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.493-504
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• 2008

In the seas around the Korean Peninsula, the seasonal cycle of zooplankton related to North Pacific regime shifts was investigated to understand the reaction of the ecosystem to climate change using long-term data on zooplankton biomass (1965-2000) and the abundance of four major zooplankton groups: copepods, amphipods, chaetognaths, and euphausiids (1978-2000). In general, the zooplankton biomass showed a large peak in spring and a small peak in autumnin Korean waters, but there was a slight difference in the peak time depending on the location and the period before and after the North Pacific regime shift. The zooplankton biomass showed conspicuous seasonal peaks in R-III (1990-2000) compared to R-I (1965-1976) and R-II (1977-1988), and the seasonal peak shifted from the autumn in R-II to the spring in R-III. The peak of copepods and euphausiids in abundance was from April to June, while chaetognaths peaked from August to October. We postulate that the time lag between the peaks for copepods and chaetognaths results from the predator-prey relationship. The regime shift in 1989 did not alter the seasonal cycle of the four major zooplankton groups, although it enhanced their production. The seasonal peaks of the four major zooplankton groups did not shift, while the seasonal peaks of the zooplankton biomass did shift. This was not only becausethe zooplankton biomass included other mesozooplankton groups but also because the abundance of the four major zooplankton groups increased significantly in spring.

• Korean Journal of Veterinary Research
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• v.17 no.2
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• pp.63-71
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• 1977

During the period of March, 1976 to December, 1976, 48 raw milk samples were taken from dairy cows at 48 different dairy farms in Korea analyzed by gas liquid chromatography to determine the seasonal variation of the amount of organochlorine pesticide residues. At the same time 80 market milk, 10 beef and 10 pork samples were analyed by the same procedure for checking residual levels. The results were summarized as follows; 1. Milk samples from 17 dairy farms (36 per cent of tatal) were shown to be contaminated with various organochlorine pesticides. The residua lrate of ${\gamma}-BHC$ in tested samples were 44per cent (14 sam ples) that of aldrine was 28 per cent (9 samples) and those of pp'-DDT, dieldrin and heptachlor were 9.3 percent (3 samples) respectively. 2. In raw milk pp'-DDT, ${\gamma}-BHC$, aldrin, dieldrin and heptachlor were detected, and aldrin, dieldrin and heptachlor were detected in the market milk. Any kinds of organochlorine pesticides were not detected in beef samples but dieldrin and heptachlor were detected in pork samples. Average residual values of aldrin, dieldrin and heptachlor in the market milk were 0.0077 ppm (0.0000~1.1100 ppm), 0.0001ppm (0.0000~0.0500 ppm) and 0.0008 ppm (0.0000~2.0520 ppm), respectively, and those of dieldrin and heptachlor in pork samples were 0.0010 ppm (0.0000~0.0100 ppm) and 0.0033 ppm (0.0000~0.0330 ppm). respectively. 3. Residues of organochlorine pesticides in raw milk were extremely variable; in fact pp'-DDT was detected in milk samples from A, B, C and D districts and endrin was not detected from all districts. The ${\gamma}-BHC$ and dieldrin were detected at the district of A, C and D, aldrin at the districts of A and C and heptachlor at the districts of both A and D. 4. Seasonal trends of residual values of organochlorine pesticides were, in general, noticeable. The residual level was much higher in Spring than in other seasons and showed the tendeney of decrease from spring through summer and autumn generally; in the case of pp'-DDT average residual values were 0.0121 ppm in spring, 0.0022 ppm in summer and not detected in autumn. But in winter ${\gamma}-BHC$ and aldrin residues were increased a little. Residual values in raw milk (when cow are fed on hay and silage) were appeared higher in winter than the other seasons. 5. Residues of organochlorine pesticides in raw milk were not related in respect to hygienic conditions of dairy farms pp'-DDT and heptachlor were, in general, detected in all farms and aldrin was more detected in milk from well sanitated farms than poor sanitated ones.