• Title/Summary/Keyword: Seasonal Use

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Composition of Phytoplankton in Gamak Bay by CHEMTAX Analyses (CHEMTAX 활용한 가막만 식물플랑크톤 군집조성)

  • Oh, Hyun-Taik;Kim, Da-Jung;Lee, Won-Chan;Jung, Rae-Hong;Hong, Suk-Jin;Kang, Yang-Sun;Lee, Yang-Woo;Tilburg, Charles
    • Journal of Environmental Science International
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    • v.17 no.10
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    • pp.1155-1167
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    • 2008
  • Chlorophyll a (chl a) has been used as an indicator for phytoplankton biomass in pelagic ecosystems due to the relative ease of measurement and selectivity for autotrophs in mixed plankton assemblages. However, the use of chi a as an indicator for phytoplankton biomass is restricted due to its inability to resolve taxonomic differences of phytoplankton and the highly variable relationship of chi a with phytoplankton. Here, we describe the analysis of High-Performance Liquid Chromatography (HPLC) photosynthetic pigment data using CHEMTAX, which is a matrix factorization program that uses chemical taxonomic indices (phytoplankton carotenoids) to quantify the abundance of phytoplankton groups. Compared to direct microscopic counting that can distinguish species within broad groups, the resolution of taxonomic groups by CHEMTAX is generally coarse. It can only distinguish between diatoms, dinoflagellates, cryptophytes, cyanobacteria, chlorophytes, prasinophytes, and haptophytes. However, CHEMTAX analysis is much faster and less expensive than microscopic counting methods. HPLC pigment observations were taken in the spring, summer, fall, and winter in$ 2005\sim2006$ within Gamak Bay, South Korea. CHEMTAX results revealed that diatoms were the dominant taxonomic group in Gamak Bay. In inner Gamak Bay, the ratio between diatoms and cryptophytes was $75\sim80%$, and the ratio between dinoflagellates and cryptophytes was $10\sim15%$. In outer Gamak Bay, the ratio between diatoms and cryptophytes was $85\sim90%$, and the ratio between dinflagellates and cryptophytes was only $1\sim5%$. The population structure was seasonal. Relative diatom populations were less in the summer than the winter season.

A Study on Minimizing of Condenser Pressure Loss according to the Temperature Rise of the Seawater for Korean Standard Coal-fired Power Plants (표준석탄화력 발전소 해수온도 상승에 따른 복수기 압력 손실 최소화 방안)

  • An, Hyo-Yoel;Moon, Seung-Jae
    • Plant Journal
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    • v.11 no.2
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    • pp.45-51
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    • 2015
  • In this paper, studied condenser operating management which is affecting power plants efficiency considering the cost of poor quality. Sea water temperature and condenser pressure have clear correlation in S power plants. As the sea water temperature changes, condenser pressure changed -1.7~+20 mmHg from design condenser pressure(38.1 mmHg). Use the heat rate correction curve from manufactory company, realized that efficiency and cost of poor quality changed 0.0201%, 12,830 won/h at Unit #1,2 but 0.0155%, 9,832 won/h when condenser pressure 1 mmHg rise. Also, checked that it is changed depend on seasonal corresponding operation, plant ageing and the point of preventive maintenance like overhaul maintenance. This study said if we considered complying with management range and planning overhaul maintenance, then it could help reducing operating maintenance losses minimum 2.5 billion won per 1 year (case : Unit #1, forty days maintenance).

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Evaluation of Tank Capacity of Rainwater Harvesting System to Secure Economic Feasibility and Sensitivity Analysis (경제성 확보를 위한 빗물이용시설의 규모 산정 및 민감도 분석)

  • Mun, Jung-Soo;Kim, Ha-Na;Park, Jong-Bin;Lee, Jung-Hun;Kim, Ree-Ho
    • Journal of Korean Society of Water and Wastewater
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    • v.26 no.2
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    • pp.191-199
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    • 2012
  • Rainwater harvesting systems (RWHS), one of measures for on site rainwater management, have been promoted by laws, regulations and guidelines and have been increased. However, more evaluation of economic feasibility on RWHS is still needed due to seasonal imbalance of rainfall and little experiences and analysis on design and operation of RWHS. In this study, we investigated tank capacity of RWHS to secure economic validity considering catchment area and water demand, which is affected by building scale. Moreover, sensitivity analysis was performed to examine the effect of design factors, cost items and increase rate of water service charge on economic feasibility. The BCR (benefit cost ratio) is proportional to the increase in tank capacity. It is increased steeply in small tank capacity due to the effect of cost and, since then, gently in middle and large tank capacity. In case of 0.05 in the rate of tank volume to catchment area and 0.005 in water demand to catchment area, BCR was over one from the tank capacity of 160 $m^{3}$ taking into account of private benefits and from the tank capacity of 100 $m^{3}$ taking into account of private and public benefits. Sensitivity analysis shows that increase of water demand can improve BCR values with little cost so that it is needed to extend application of rainwater use and select a proper range of design factor. Decrease of construction and maintenance cost reduced the tank volume to secure economic validity. Finally, increase rate of water service charge had considerable impact on economic feasibility.

Movement patterns and home range of captive-bred Amur ratsnake (Elaphe schrenckii) juveniles in the natural habitat

  • Kim, Dae-In;Kim, Il-Hoon;Kim, Ja-Kyeong;Kim, Bin-Na;Park, Dae-Sik
    • Journal of Ecology and Environment
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    • v.35 no.1
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    • pp.41-50
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    • 2012
  • To determine the movement patterns, home range, and use of structural features of captive-bred one- or two-year-old Amur ratsnake (Elaphe schrenckii) juveniles in the natural habitat, we radio-tracked a total of 11 juvenile snakes in a mountain valley in Chiaksan National Park, South Korea, between August 21 and September 20, 2010 and between June 13 and July 13, 2011. During the first week of the release, most juveniles moved short distances, daily, but they increased their distances after the first week. The body weight of the juveniles was negatively related with the movement rate (dividing the number of movements by the number of relocations), which was positively related with the mean daily distances moved and the size of both a kernel 50% and 95% home range. During the study period, the juveniles moved daily, approximately 17 m, and the size of the minimum convex polygon and the 50% and 95% kernel home ranges were 1.8 ha, 0.4 ha, and 3.0 ha, respectively. The released captive-bred juveniles were more frequently confirmed underground or on the ground rather than on rocks or on trees. Our results suggest that the body condition of released individuals, the seasonal time of the release, and the existence of available prey and shelters in the habitat should be carefully considered when releasing captive-bred Amur ratsnake juveniles for the rehabilitation of field populations.

A Study of five elements in 『Hyupgiltongui』 Bonwon chapter one (『협길통의(協吉通義)』 본원일(本原一)의 5행(行)에 관한 연구)

  • Kwon, Yung-soo;Kim, Ki-Seung
    • Industry Promotion Research
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    • v.5 no.3
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    • pp.135-144
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    • 2020
  • Five elements that form all things have been symbolized in that they are indispensable elements in human life. Moreover, each unique energy has been used to explain the existence of all creation and the origin of action. The theory of five elements can be changed and utilized into various forms, including co-existence and conflict of five elements, five elements itself, the combination of Ganji five elements, Wangsanhyususa(旺相休囚死), five elements and Yin-yang. Especially, 『Hyupgiltongui Bonwon chapter one covers five elements, five elements of Ganji, seasonal use of five elements, prosperity and decline of five elements depending on seasons, Union of 3 elements among Twelve Zodiac Signs(三合), Union of two elements among Twelve Zodiac Signs(六合), changes of Cheongan 5hab. Therefore, if you analyze and utilize them, you can tell someone's fortune by theory of five elements only and read fortune in detail by combining it with other theories.

Estimation of the Temporal and Spatial Variation of Surface Temperature Distribution in the Korean Peninsula using NOAA/AVHRR Data (NOAA/AVHRR 위성자료를 이용한 한반도 표면온도의 시공간적 변동 추정)

  • Suh, Young-Sang;Lee, Gi-Chul;Lee, Na-Kyung;Jo, Myung-Hee
    • Journal of the Korean Association of Geographic Information Studies
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    • v.8 no.3
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    • pp.150-160
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    • 2005
  • In this study, the spatiotemporal surface temperature changes were analyzed in the Korean peninsula. The surface temperature variation was estimated using the split window method and NOAA/AVHRR data in 1991, 1995 and 2000. The ranges of differences in temperature between day time and night time were $3-15^{\circ}C$ around the peninsula. The differences in seasonal variations and yearly fluctuations in big cities were lower than those in rural areas and showed clearly the effects of the urbanization. The characteristics of urban heat affects were further determined based on the day and night time temperature comparison on Busan metropolitan area between these periods. Finally, the future use of this technology was suggested for the urban environmental planning.

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Heating Performance of Geothermal Heat Pump System Applied in Cold Climate Region(Mongolia) (한랭지(몽골) 지열 히트펌프 시스템의 난방 성능 분석)

  • Sohn, Byonghu;Choi, Jae Ho;Min, Kyung Chon
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.27 no.1
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    • pp.31-38
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    • 2015
  • Geothermal heat pump (GHP) systems have become an efficient alternative to conventional cooling and heating methods due to their higher energy using efficiency. These systems use the ground as a heat source in heating mode operation and a heat sink in cooling mode operation. The aim of this study is to evaluate the heating performance of the GHP system for a residential building ($420m^2$) in Ulaanbaatar, Mongolia. In order to demonstrate the feasibility of a sustainable performance of this system, we installed the water-to-water geothermal heat pump with ten vertical ground heat exchangers and measured operation parameters from October 19, 2013 to March 26, 2014. The results showed that the entering source temperature of brine from the ground heat exchangers was in a range of the design target temperature of $-10^{\circ}C$ for heating. For total values of the representative results, the ground heat exchangers extracted heat of 53.51 MWh from the ground. In addition, the GHP system supplied heat of 83.55 MWh to the building and consumed power of 30.27 MWh. Consequently, the average heating seasonal performance factor ($SPF_h$) of the overall system was evaluated to be 2.76 during the measurement period of the heating season.

Effect of adult population density on egg production in the black soldier fly, Hermetia illucens (Diptera: Stratiomyidae)

  • Park, kwanho;Kim, Wontae;Kim, Eunsun;Choi, Ji-Young;Kim, Sung-Hyun
    • International Journal of Industrial Entomology and Biomaterials
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    • v.33 no.2
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    • pp.92-95
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    • 2016
  • The black soldier fly is economically important because its prepupae are used as feed for many animals, including fish and swine. In Korea, black-soldier-fly farms have attempted to increase annual breeding and mass egg production for use in animal feed, as well as the decomposition of organic waste. Such efforts require an understanding of optimal mating and oviposition techniques. Specifically, adult densities and cage size may both improve the efficiency of mass egg production. Our study used four sizes of nylon cages ($1.0{\times}1.0{\times}2.5m$, $1.5{\times}1.5{\times}2.5m$, $2.0{\times}2.0{\times}2.5m$, $2.5{\times}2.5{\times}2.5m$) and three density treatments (4 kg, 8 kg, and 10 kg of pupae) to investigate optimal habitat size and adult density. We found that cage size (independent of density) did not significantly influence female fecundity (number of egg clutches and egg weight), whereas higher densities increased egg number and weight regardless of cage size. Thus, we recommend manipulating adult density to enhance productivity in commercial black-soldier-fly farming. However, we also propose further detailed research to develop methods that account for seasonal changes and environmental conditions, as climatic variables (temperature, sunlight) likely influence female fecundity as well.

The Correlation between Groundwater Level and the Moving Average of Precipitation considering Snowmelt Effect and Critical Infiltration in Han River Watershed (융설효과와 한계침투량을 고려한 한강유역의 지하수위와 강우이동평균간의 상관관계)

  • Yang, Jeong-Seok;Kim, Nam-Ki
    • The Journal of Engineering Geology
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    • v.19 no.3
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    • pp.313-321
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    • 2009
  • The relationship between precipitation and groundwater level and the correlation between the moving average of precipitation and goundwater level were analyzed for the Han river watershed in Korean peninsular. Fourteen regions in the watershed were selected and there were somewhat different patterns of seasonal fluctuation of groundwater level data. The groundwater level data tends to decrease in dry spell and increase in wet spell however the range between maximum and minimum values is quite different for each gauging point. We could have stronger correlation between groundwater level for fractured rock aquifer and the moving average of precipitation than the groundwater level for alluvial aquifer. The critical infiltration, which is the maximum daily infiltration averaged throughout watershed, value is turned out to have the range of 10 to 90 mm. We could have stronger correlation when we consider critical infiltration and modify the original precipitation data than we use original precipitation data. We also could have higher correlation coefficient when we consider snowmelt effect for the watershed that has considerable snow event.

The Design and Implementation of a Vendor Managed Inventory System for Smaller Online Shopping Malls (중소 인터넷 쇼핑몰을 위한 판매자 재고관리 시스템 설계 및 구현)

  • Choi, O-Hoon;Lim, Jung-Eun;Na, Hong-Seok;Baik, Doo-Kwon
    • Journal of Digital Contents Society
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    • v.9 no.2
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    • pp.295-303
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    • 2008
  • With universality of e-commerce through internet, smaller online shopping malls are increased. A Smaller online shopping mall by nature lacks an extra space to load many inventory quantities. Therefore, it is difficult to response immediately with client request with traditional inventory management method. VMI has a character that supplier can control volume of inventory according to sales of seller. This paper proposes SOHO-VMI that is applied VMI into smaller online shopping mall. Proposed SOHO-VMI supports M $\times$ N structure can interact with multiple suppliers and sellers. And it uses XML/EDI for interaction with EDI documents use to legacy system. Also, This paper proposes logistics statistic prediction algorithm can adjust production and distribution volumes to supplier considering seller's product distribution information and seasonal factor.

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