• Title/Summary/Keyword: Four Season

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Abundance and expression of denitrifying genes (narG, nirS, norB, and nosZ) in sediments of wastewater stabilizing constructed wetlands

  • Chon, Kyongmi;Cho, Jaeweon
    • Environmental Engineering Research
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    • v.20 no.1
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    • pp.51-57
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    • 2015
  • As expected, the expression of denitrifying genes in a Typha wetland (relatively stagnant compared to other ponds), showing higher nitrogen removal efficiency in summer, was affected by temperature. The abundance and gene transcripts of nitrate reductase (narG), nitrite reductase (nirS), nitric oxide reductase (norB), and nitrous oxide reductase (nosZ) genes in seasonal sediment samples taken from the Acorus and Typha ponds of free surface flow constructed wetlands were investigated using quantitative polymerase chain reaction (Q-PCR) and quantitative reverse transcription PCR (Q-RT-PCR). Denitrifying gene copy numbers ($10^5-10^8$ genes $g^{-1}$ sediment) were found to be higher than transcript numbers-($10^3-10^7$ transcripts $g^{-1}$ sediment) of the Acorus and Typha ponds, in both seasons. Transcript numbers of the four functional genes were significantly higher for Typha sediments, in the warm than in the cold season, potentially indicating greater bacterial activity, during the relatively warm season than the cold season. In contrast, copy numbers and expression of denitrifying genes of Acorus did not provide a strong correlation between the different seasons.

Feeding of Sugar Cane Silage to Dairy Cattle during the Dry Season

  • Suksombat, Wisitiporn;Junpanichcharoen, P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.8
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    • pp.1125-1129
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    • 2005
  • A study was conducted to determine the effect of feeding sugar cane silage compared to chopped whole sugar cane or grass silage on performances of lactating dairy cows during the dry season. Twenty four Holstein Friesian crossbred (>87.5% Holstein Friesian) lactating dairy cows in mid lactation; averaging 15.4${\pm}$3.2 kg of milk, 120${\pm}$23 days in milk, 50.5${\pm}$6.5 months old and 432${\pm}$39 kg live weight, were stratified for milk yield, days in milk, age, stage of lactation and body weight, and then randomly allocated to three treatment groups (8 cows in each group). All cows were fed 7.5 kg/d commercial concentrate plus ad libitum roughage according to treatment groups, which were grass silage, sugar cane silage or chopped whole sugar cane respectively. All cows consumed similar DM and produced similar milk and milk composition yields. However, cows on grass silage lost more weight than the other cows. The present study indicated that, during the dry season, sugar cane silage can be fed to lactating dairy cows, while giving similar milk yield to grass silage or chopped whole sugar cane.

Chemical Composition of Cirsium japonicum var. ussurience Kitamura and the Quantitative Changes of Major Compounds by the Harvesting Season (엉겅퀴 정유의 화학적 조성 및 수확시기에 따른 주요 화합물 함량 변화)

  • Choi, Hyang-Sook
    • The Korean Journal of Food And Nutrition
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    • v.29 no.3
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    • pp.327-334
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    • 2016
  • This study investigated the chemical composition of Cirsium japonicum var. ussurience Kitamura essential oil and the quantitative changes of major volatile flavor compounds according to the harvesting season. The essential oils obtained by the method of hydrodistillation extraction from aerial parts of C. japonicum var. ussurience Kitamura were analyzed by GC and GC-MS. Sixty-four volatile flavor compounds were identified in the essential oil from C. japonicum var. ussurience Kitamura harvested in May 2012; hexadecanoic acid (49.31%) was the most abundant compound, followed by 6,10,14-trimethyl-2-pentadecanone (13.72%), phytol (13.40%) and 9-hexadecenoic acid (4.16%). Eighty-three compounds were identified in the essential oil from the plant harvested in October 2012; phytol (40.56%), hexadecanoic acid (17.69%), 6,10,14-trimethyl-2-pentadecanone (13.71%), and caryophyllene oxide (4.15%) were the most abundant compounds. Types and levels of volatile compounds from different harvesting seasons varied. The essential oil composition of C. japonicum var. ussurience Kitamura harvested in the spring and autumn was characterized by higher contents of aliphatic fatty acid, diterpene and sesquiterpene, respectively.

Distribution and Species Composition of Larval Fish during Winter Season in Jinhae Bay, Korea (동계 진해만에서의 자어 분포 및 종조성)

  • Lee, Jeong-Hoon;Kim, Jung-Nyn;Nam, Kimun;Kim, Chang-Won;Kim, Joo-Il
    • Korean Journal of Ichthyology
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    • v.26 no.2
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    • pp.133-138
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    • 2014
  • We investigated the spacial distribution and species composition of fish larvae during winter season (January 2013~March 2013) in Jinhae Bay, Korea. During the study period, a total of 12 larvae species belonging to 8 families were collected, and the dominant species were Pholis crassispina, Clupea pallasii, Liparis tanakae, Hexagrammos otakii. These four species accounted for 93% of the total number of individual collected. High density and species diversity occurred around Jam-do and eastern area of Chilcheon-do, suggesting that these areas are the main spawning ground of fish larvae in Jinhae Bay.

THE CHANGES OF CHEMICAL PROPERTIES OF FOREST SOILS IN DRY AND WET SEASONS (건우기에 산림토양의 화학성분의 변화)

  • CHA, Jong Whan
    • Journal of Plant Biology
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    • v.7 no.2
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    • pp.1-8
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    • 1964
  • Cha, Jong Whan (Dept. of Biology, Graduate School, Dong Kuk Univ.) The changes of chemical properties of forest soils in dry and wet seasons. Kor. Jour. Bot. VII(2): 1-8, 1964. Soil selected for the present investigation was collected from a mountain of the Forestry Experiment Station of the vicinity of Seoul. The forest communities studied were three forest and a unplanted soils. The soil samples were obtained from each forest type during dry and wet seasons. And these samples were collected from four horizons of all communities respectively. It was showed that exchangeable hydrogen was increased by rainfall, and total exchangeable base decreased in the same way. The content of nitrogen is washed away by rainfall, especially ammonium nitrogen was highly significant between dry and wet season. On the contrary, organic matter and available phosphorus were of no significant difference between dry and wet seasons. The values of pH appeared a different response in dry and wet seasons according to the plant communities. The needle-leaved forest soils showed more acidity than the broad-leaved forest soils, and the least acidity in open places. All nutrients in soil studied gradually decreased down the profiles. According to statistical analyses of the soil components among all soil horizons, total exchangeable bases in wet season indicated only significant at 1%. Exchangeable hydrogen and organic matter of the soil in dry season was particularly very low with increased depth in the profile. The fertility level of most forested soils selected for the present investigation is low according to chemical tests for available nutrient elements.

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A Study of Comparison of Temperature Seasons and Biotic Seasons in Jeonnam Region

  • Hwang, Sung Eun;Ryu, Chan Su
    • Journal of Integrative Natural Science
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    • v.6 no.2
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    • pp.118-123
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    • 2013
  • Korea, which is located in the middle-latitude area of the northern hemisphere, has four seasons. These seasons can be classified based on their months, mean temperatures, biology and natural phenomena. In this study, climatic changes were identified by biotic and temperature seasons, changing trends were compared by season, and the appropriateness of the biotic phenomena for the biotic season classification was examined. The data for this study included the mean temperatures, and biology phenomenon observation dates, which had been observed for 38 years from the ASOSs in seven Gwangju and Jeonnam regions. Limitations were found in the classification of the temperature and biotic seasons. Especially in the case of the biotic season based on a single life, the points of the first sighting and the initial sound fluctuated so much that the accuracy of the results was not guaranteed. Therefore, the life species had to be selected subject to detailed verification and accurate specifications, and to be applied to the meteorological phenomena. In addition, there were lives in the standard biology that could no longer be observed because of environmental pollution and climatic change, which indicates the need to protect the existing standard biology.

Historical changing of flow characteristics over Asian river basins

  • Ha, Doan Thi Thu;Kim, Tae-Son;Bae, Deg-Hyo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2020.06a
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    • pp.118-118
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    • 2020
  • This study investigates the change of flow characteristics over 10 Asian river basins in the past 30 years (1976-2005). The variation is estimated from The Soil and Water Assessment Tool (SWAT) model outputs based on reanalysis data which was bias-corrected for Asian monsoon reagion. The model was firstly calibrated and validated using observed data for daily streamflow. Four statistical criteria were applied to evaluate the model performance, including Coefficient of determination (R2), Nash - Sutcliffe model efficiency coeffi cient (NSE), Root mean square error-observations standard deviation ratio (RSR), and Percentage Bias (PBIAS). Then parameters of the model were applied for the historical period 1976-2005. The estimates show a temporal non-considerable increasing rate of daily streamflow in most of the basins over the past 30 years. The difference of monthly discharge becomes more significant during the months in the wet season (June to September) in all basins. The seasonal runoff shows significant difference in Summer and Autumn, when the rainfall intensity is higher. The line showing averaged runoff/rainfall ratio in all basins is sharp, presenting high variation of seasonal runoff/rainfall ratio from season to season.

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A Model of Four Seasons Mixed Heat Demand Prediction Neural Network for Improving Forecast Rate (예측율 제고를 위한 사계절 혼합형 열수요 예측 신경망 모델)

  • Choi, Seungho;Lee, Jaebok;Kim, Wonho;Hong, Junhee
    • Journal of Energy Engineering
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    • v.28 no.4
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    • pp.82-93
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    • 2019
  • In this study, a new model is proposed to improve the problem of the decline of predict rate of heat demand on a particular date, such as a public holiday for the conventional heat demand forecasting system. The proposed model was the Four Season Mixed Heat Demand Prediction Neural Network Model, which showed an increase in the forecast rate of heat demand, especially for each type of forecast date (weekday/weekend/holiday). The proposed model was selected through the following process. A model with an even error for each type of forecast date in a particular season is selected to form the entire forecast model. To avoid shortening learning time and excessive learning, after each of the four different models that were structurally simplified were learning and a model that showed optimal prediction error was selected through various combinations. The output of the model is the hourly 24-hour heat demand at the forecast date and the total is the daily total heat demand. These forecasts enable efficient heat supply planning and allow the selection and utilization of output values according to their purpose. For daily heat demand forecasts for the proposed model, the overall MAPE improved from 5.3~6.1% for individual models to 5.2% and the forecast for holiday heat demand greatly improved from 4.9~7.9% to 2.9%. The data in this study utilized 34 months of heat demand data from a specific apartment complex provided by the Korea District Heating Corp. (January 2015 to October 2017).

A Study on the Air Pollution Around a Major Trunk Road in Urban Area (1) Measurements of $NO_2$ Concentrations in Homes Along the Major Arterial Roads in Tokyo (도시에 있어서 연도오염에 관한 연구 (1) 동경도 연도가정의 $NO_2$ 농도 측정)

  • 손부순
    • Journal of Environmental Health Sciences
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    • v.21 no.3
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    • pp.107-114
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    • 1995
  • To assess the contribution of automobile exhaust to indoor and outdoor levels of $NO_2$ around a major trunk road in Tokyo, $NO_2$ levels of 200 homes were measured at living rooms, kitchens and outdoor at each season, from the summer of 1990 to the spring of 1991, $NO_2$ level was measured for four days using diffusion $NO_2$ dosimeter. Outdoor $NO_2$ levels at each season and indoor $NO_2$ levels at seasons when heaters were not used decreased according to the distance from the roadside. The differences between $NO_2$ levels at zone I(within 20m from the roadside) and zone III(beyond 50m) was about 3 ppb. Automobile exhaust seemed to contribute to this difference. At seasons when heaters were used, indoor $NO_2$ levels of the homes equipped with vented heater, decreased according to the distance from the roadside. However, there was no correlation between indoor levels and the distance from the roadside at homes equipped with unvented heater.

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Comfort Properties of Silk#x00B7;Rayon-Cellulose Fiber Union Fabrics (견·인견과 셀룰로오스섬유 교직물의 쾌적성능 평가)

  • Bae, Young Hee;Yun, Chang Sang;Jeong, Woon Seon
    • The Korean Journal of Community Living Science
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    • v.27 no.4
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    • pp.795-801
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    • 2016
  • This study was conducted to suggest the best union fabric to combine with cellulose fiber for summer and in-between seasons. Four types of union fabric, viz. silk/flax, silk/cotton, rayon/flax and rayon/cotton, were used as sample fabrics after weaving them in a local textile factory. The air permeability, moisture regain, water absorption, water vapor permeability and thermal insulation of the samples were tested. The results are as follows. The rayon/flax union fabric is the most suitable for summer clothes due to its having the best comfort property of air and water vapor permeability, and moisture and water absorption. For in-between seasons, it is recommended to use the silk/cotton union fabric because of its good thermal insulation properties.