• Korean Journal of Environment and Ecology
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• v.34 no.2
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• pp.121-129
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• 2020

This study investigated the change of benthic macroinvertebrates community due to erosion control dams installed in Wonju, Gangwon by comparing the data before and after a rainy season. It selected a closed-type erosion control dam (boulder stone), an open-type erosion control dam (buttress), and a control area and surveyed two upstream points and two downstream points four times between March and September 2019. The flow velocity mostly increased in the closed-type, open-type, and control areas but decreased in St. 3 after the rainy season. The number of benthic macroinvertebrates species and their populations mostly decreased after the rainy season, and the rate of decrease in the populations in the open-type and control areas were more similar than the closed-type area. Species and populations of the EPT groups mostly decreased after the rainy season. A result of the similarity analysis showed that the closed-type and open-type areas were separated by 38.4% with the control area before the rainy season, but the open-type and control areas were separated by 51.3% with the closed-type area after the rainy season. A result of the principal components analysis (PCA) based on axis 1 showed that the closed-type area had a positive value before and after the rainy season, and the open-type and control areas had a negative value before and after the rainy season. The open-type area was more correlated with the control area than the close type. The analysis of the EPT groups showed the distribution of Ephemeroptera in the closed-type area and Trichoptera in the open-type and control areas. The result of this study shows that the installation of erosion control dam can cause changes in benthic macroinvertebrates community and that the open-type area had a smaller difference community difference from the control area after the rainy season than the closed-type area.

• Journal of Environmental Science International
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• v.15 no.12
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• pp.1125-1139
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• 2006

The cluster analysis of diurnal precipitation patterns is performed by using daily precipitation of 59 stations in South Korea from 1973 to 1996 in four seasons of each year. Four seasons are shifted forward by 15 days compared to the general ones. Number of clusters are 15 in winter, 16 in spring and autumn, and 26 in summer, respectively. One of the classes is the totally dry day in each season, indicating that precipitation is never observed at any station. This is treated separately in this study. Distribution of the days among the clusters is rather uneven with rather low area-mean precipitation occurring most frequently. These 4 (seasons)$\times$2 (wet and dry days) classes represent more than the half (59 %) of all days of the year. On the other hand, even the smallest seasonal clusters show at least $5\sim9$ members in the 24 years (1973-1996) period of classification. The cluster analysis is directly performed for the major $5\sim8$ non-correlated coefficients of the diurnal precipitation patterns obtained by factor analysis In order to consider the spatial correlation. More specifically, hierarchical clustering based on Euclidean distance and Ward's method of agglomeration is applied. The relative variance explained by the clustering is as high as average (63%) with better capability in spring (66%) and winter (69 %), but lower than average in autumn (60%) and summer (59%). Through applying weighted relative variances, i.e. dividing the squared deviations by the cluster averages, we obtain even better values, i.e 78 % in average, compared to the same index without clustering. This means that the highest variance remains in the clusters with more precipitation. Besides all statistics necessary for the validation of the final classification, 4 cluster centers are mapped for each season to illustrate the range of typical extremities, paired according to their area mean precipitation or negative pattern correlation. Possible alternatives of the performed classification and reasons for their rejection are also discussed with inclusion of a wide spectrum of recommended applications.

• The Korean Journal of Applied Statistics
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• v.24 no.3
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• pp.535-546
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• 2011

This study develops statistical models for the binary forecast of Asian dust days over South Korea in the winter season. For this study, we used three kinds of data; the rst one is the observed Asian dust days for a period of 31 years (1980 to 2010) as target values, the second one is four meteorological factors(near surface temperature, precipitation, snowfall, ground wind speed) in the source regions of Asian dust based on the NCEP reanalysis data and the third one is the large-scale climate indices. Four kinds of statistical models(multiple regression models, logistic regression models, decision trees, and support vector machines) are applied and compared based on skill scores(hit rate, probability of detection and false alarm rate).

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.1
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• pp.55-60
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• 2002

A metabolism trial with four castrated male Brahman cattle, average body weight 320 kg, was conducted in order to determine the nutritive value of chopped sugarcane stalk (CSS) for the establishment of feeding strategy in the dry season in Northeast Thailand. Animals were subjected to the following four dietary treatments: Treatment 1; 100% of CSS, Treatment 2; 70% of CSS and 30% of commercial complete feed (TMR), Treatment 3; 40% of CSS and 60% of TMR, and Treatment 4; 100% of TMR. The average CP, ether extracts, nitrogen free extracts, crude fiber and ash contents of CSS were 2.0, 0.9, 79.0, 16.1 and 2.2%, respectively. Although the amount of feed given was approximately at maintenance level, animals in treatments 1 and 2 refused a part of feed. The metabolism trial revealed that total digestible nutrient and metabolizable energy contents of CSS were 61.5% and 9.04 MJ/kgDM, respectively, when it was properly supplemented with protein sources. Nutritive value of CSS was lowered when animals were given CSS solely. This was due to the large loss of energy into urine and methane. Voluntary intake of CSS in cattle was not enough to satisfy energy requirement for maintenance. The CSS can be used as a roughage for feeding cattle in the dry season with proper supplementation of protein and energy.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.5
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• pp.515-522
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• 1995

The field experiment was carried out to study the growth and fodder yield of the Gliricidia sepium provenances in fence system in dryland farming area in Bali, Indonesia for 24 months. The design of the experiment was a completely randomized block arrangement, consisted of 16 treatments (Gliricidia sepium provenances) and 12 blocks with 10 plants per provenance. Of the 16 gliricidia provenances, six were from Mexico (M), four were from Guatemala (G), and one each was from Colombia (C), Indonesia (I), Nicaragna (N), Panama (P), Costa Rica (R) and Venezuela (V). After 40 weeks establishment the gliricidia were lopped regularly 4 times a year, twice during the four month wet season and twice during the eight month dry season at 150 cm height. There were variations (p < 0.05) in stem elongation from 10 to 121 cm, leaf retained from 48 to 105%, leaf shedding from 53 to 86%, branch number from 4 to 7, fodder yield from 281 to 648 g DW/plant, and wood yield from 53 to 179 g DW/plant; and such variations were affected by the seasons. Retalhuleu provenance of Guatemala (G14), Belen provenance of Nicaragua (N14) and Bukit Bali provenance of Indonesia (I) were ranked first, second and third, respectively, measured in terms of stem elongation, leaf retention, fodder and wood yields during the wet and dry seasons.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.5
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• pp.658-664
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• 2002

This study was conducted to determine a proper feeding regime for lactating Holstein cows during the warm season in Taiwan. In Feeding Trial, 21 lactating Holstein cows were randomly allotted into three feeding regimes in a Completely Randomized Design. The feeding regimes were roughage fed ad libitum along with concentrate fed either twice daily (2C) or four times daily (4C), and total mixed ration (TMR) for 8 weeks. No significant differences among the three feeding regimes were found in body weight changes, and intakes in terms of dry matter, crude protein and net energy. For milk yield and 4% FCM yield, 4C were higher than the other two feeding regimes (p<0.05). No significant differences were found in milk compositions or differences noted in the yields of the respective milk components. TMR was worse than 2C and 4C (p<0.05) in milk production efficiencies in terms of dry matter intake per kg milk yield, crude protein intake per kg milk protein yield, as well as dry matter intake, net energy intake and crude protein intake per kg 4% FCM yield. Three ruminally fistulated Holstein dry cows were randomly assigned into the same three feeding regimes in a 3${\times}$3 Latin Square Design. No significant differences were found among the feeding regimes in ruminal pH, ammonia nitrogen, total VFA concentration, molar percentages of VFA, and acetic acid: propionic acid ratio (C$_2$/C$_3$). Taken all together, roughage fed ad libitum and concentrate fed four times daily was the better feeding regime for lactating cows during the warm season in Taiwan.

• Journal of Korean Medical classics
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• v.22 no.3
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• pp.133-144
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• 2009

Objective : We try to find out the literature and clinical evidences of seasonal formula through the analysis of the addition and subtraction of medical herbs in the formula according to the season. Method : In this study, we analyzed 122 seasonal prescriptions from "Dong-uibogam(東醫寶鑑)", "Bang-yakhappyeon(方藥合編)", "Jeongchijunsueng(證治準繩)", "Dangyesimbeop(丹溪心法)", "Uihakimmun(醫學入門)", "Uihakjeongjeon(醫學正傳)", "Gyeong-akjeonseo(景岳全書)" and "Taepyeonghyeminhwajegukbang(太平惠民和劑局方)". Results : In spring, pungent-warm herbs such as the dried rhizome of cnidium officinale Makino, the dried root of SEdebouriella divaricata (Turcz.) Schischk. are used. In summer, bitter-cold such as the dried root of Scutellaria baicalensis Georgi, the dried rhizome of Coptis chinensis Franch. or pungent herbs such as the dried aerial part of Elsholtzia splendens Nakai, the dried ripe seed of Dolichos lablab L. are added. In fall and winter, pungent-bitter-hot herbs such as the dried ripe fruit of Evodia rutaecarpa Benth., the dried rhirome of Zingiber officinale Rosc. are used. Conclusions : In this paper, we have shown that several medical herbs could be added and subtracted in the formula according to the season because they have the seasonal characteristic Gi or treat seasonal pathogens.

• Development and Reproduction
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• v.23 no.4
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• pp.323-331
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• 2019

In this study, an experiment was conducted to investigate the annual reproductive cycle of a Korean flat bittering, Acheilognathus rhombeus, from Ogok-myeon located in Seomjin River. The reproductive cycle was examined histologically regarding water temperature and day length of the habitat, the gonadosomatic index (GSI), and developmental characteristics of female and male gonads. The maximum GSI was found to be 3.50±0.53 and 1.36±0.14 for females and males, respectively, when the water temperature and day light was 16.9℃ and 11.3 hours, respectively in October 2018. On the other hand, the minimum GSI was found to be 0.16±0.09 and 0.69±0.15 for males and females in December 2018 and February 2019, respectively. The ovipositor of females appeared from August to November 2018. We compared and calculated the stages of germ cell developmental characteristics in the testis and ovaries to determine the reproductive cycle. According to the result, we classified the female A. rhombeus reproductive cycle into four phases, which are ripe and spawning phase (October), degenerative phase (November to December), growing phase (January to March) and mature phase (April to September). The annual reproductive cycle of male A. rhombeus was categorized into four phases: mature phase (June to October), degenerative phase (November to March), resting phase (April) and growing phase (May). The Korean flat bittering is an autumn-spawner as the main spawning season in October. In male, testicular spermatogonia appeared all year-round, and the ripe and releasing phase, which is characteristics of the spawning season in other fish, did not appear.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1417-1429
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• 2004

The objective of the paper was to study the drinking and other related behavior of dairy cows (Bos taurus). There were 142 Holstein dairy cows observed and compared in this study. The experiment was designed on the basis of two different housing systems (wet pad with forced ventilation cooling house and open house); two different seasons (winter and summer); four different stages (high milk yielding cows, low milk yielding cows, dry cows, and heifers); and grouping (home and visitor animals). All cows had free access to water. Dairy cows spent 13.8 min/day drinking in wet-pad house and 11.7 min/day in open house. owever, there was no significant difference in the duration of water drinking between these two housing systems (p>0.05). The water consumption was significantly higher in wet-pad housed animals (68 L/day) than open-housed animals (31.5 L/day) (p<0.05). A significant interaction between housing and grouping (p<0.05) was found. Home and visitor animals spent more time drinking in open house, wet-pad house, respectively. A highly significant interaction was found between housing and drinking time during the day (p<0.001). Animals in open house drank more during the morning (6:00 to 10:00 h), whereas wet-pad housed animals drank in the afternoon (14:00 to 15:00 h) and evening (18:00 to 20:00 h). The average time a cow spent in drinking in summer was not ignificantly different from that of drinking in winter. However, the water intake was significantly higher in summer (61.9 L/day) than in winter (38.6 L/day) (p<0.05). Drinking activity showed a highly significant interaction between season and physiological stage (p<0.01). High milk yield cows spent more time drinking in summer than in winter, whereas cows in all other stages followed the opposite drinking pattern. Grouping exchange did not influence the drinking behavior of dairy cows in either season (p>0.05); both home and visitor animals spent almost the same time in drinking water. A strong significant interaction between season and time during the day was found(p<0.01), suggesting that animal's high drinking frequency occurred during the daytime for both seasons, with a peak midday in winter and two peaks at 10:00 h in the morning and 19:00 h in summer. Thus, drinking behavior was associated with the cooler time of day in summer and with the warmer hours of day in winter. High and low milk yielding cows and heifers spent 15.3 min/day, 14.3 min/day, and 12.8 min/day, respectively, in water drinking activity, but there was no significant difference among them (p>0.05). There was, however, a significant difference in water drinking activity found in dry cows, which spent less time in drinking at 8.2 min/day (p<0.05).

• Weed & Turfgrass Science
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• v.3 no.1
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• pp.41-49
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• 2014

Four preparations of liquid turfgrass fertilizers were tested cool season turfgrasses during fall season. The preparations of PS-A, PS-B, PH-C and PH-D for commercial products were contained with essential nutrient elements, seaweed extract, amino acids, and humus substance. Growth and quality of creeping bentgrass (Agrostis palustris Huds cv. Penn-A1) and Kentucky bluegrass (Poa pratensis L.) mixture (Midnight 33%, Moonlight 33%, Prosperity 33%) were evaluated by normalized difference vegetation index (NDVI), root length and fresh weight, shoot density, turf color, and chlorophyll content. Three foliar sprays of 4 preparations with an interval of 7 days were made in the fall of 2013 in the sod production field at Hapchun, Korea. No significant difference among 3 preparations was found in NDVI of creeping bentgrass. However, PS-A was significantly increased NDVI of Kentucky bluegrass. Two to three applications of PS-A significantly increased chlorophyll content and turf color. Three foliar sprays of PS-A and PS-B were significantly increased the shoot density of Kentucky bluegrass on 20 days after final application. These results may indicate that the use of some preparation is beneficial in producing higher quality turfgrass sod with better color and chlorophyll content during fall season.