• 제목/요약/키워드: Operation conditions

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Analysis of Long-Term Variation in Marine Traffic Volume and Characteristics of Ship Traffic Routes in Yeosu Gwangyang Port (여수광양항 해상교통량의 장기변동 및 통항 특성)

  • Kim, Dae-Jin;Shin, Hyeong-Ho;Jang, Duck-Jong
    • Journal of the Korean Society of Marine Environment & Safety
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    • 제26권1호
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    • pp.31-38
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    • 2020
  • The characteristics of ship traffic routes and the long term fluctuation in marine traf ic volume of the incoming and outgoing routes of the Yeosu Gwangyang Port were analyzed using vessel traffic data from the past 22 years and a real-time vessel traffic volume survey performed for 72 hours per year, for three years, between 2015 and 2017. As of 2017, the number of vessels passing through Yeosu Gwangyang Port was about 66,000 and the total tonnage of these ships was about 804,564 thousand tons, which is a 400 % increase from the 189,906 thousand tons shipped in 1996. Specifically, the dangerous cargo volume was 140,000 thousand tons, which is a 250 % increase compared to 1996. According to the real-time vessel traffic volume survey, the average daily number of vessels was 357, and traf ic route utilization rates were 28.1 % in the Nakpo sea area, 43.8 % in the specified sea area, and the coastal area traf ic route, Dolsan coastal area, and Kumhodo sea area showed the same rate of 6.8 %. Many routes meet in the Nakpo sea area and, parallel and cross passing were frequent. Many small work vessels entered the specific sea area from the neighboring coastal area traffic route and frequently intersected the path of larger vessels. The anchorage waiting rate for cargo ships was about 24 %, and the nightly passing rate for dangerous cargo ships such as chemical vessels and tankers was about 20 %. Although the vessel traffic volume of Yeosu Gwangyang Port increases every year, the vessel traffic routes remain the same. Therefore, the risk of accidents is constantly increasing. The route conditions must be improved by dredging and expanding the available routes to reduce the high risk of ship accidents due to overlapping routes, by removing reefs, and by reinforcing navigational aids. In addition, the entry and exit time for dangerous cargo ships at high-risk ports must be strictly regulated. Advancements in the VTS system can help to actively manage the traffic of small vessels using the coastal area traffic route.

Middle School Home Economics Teachers' Recognition of the Importance and the Level of Teaching Performance regarding the Contents of Morality Education in Home Economics Instruction (중학교 가정과교사의 가정교과에서의 도덕성 교육에 대한 중요도와 지도수행 정도)

  • Cho Mi Ok;Chae Jung Hyun
    • Journal of Korean Home Economics Education Association
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    • 제17권2호
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    • pp.257-272
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    • 2005
  • The purpose of this study is to provide the basic data for morality of education in home economics education. Through research on the state of morality of education, the following criteria can be achieved ; recognition of the importance, and the level of teaching performance regarding the contents of morality education in home economics instruction. The basic data were obtained by looking at the differences between the recognized importance and the level of teaching performance. Data were collected from the survey mailed to the teachers responsible for home economics area in $\lceil$Technology${\cdot}$Home Economics$\rfloor$ in middle schools in Korea. The 335 questionnaires collected were used for final analysis. SPSS/WIN 10.0program was used for calculating and analysis the frequency, percentage, average. standard deviation. Firstly, most of the home economics teachers show that they continually try to implement morality education through each home economics lesson plan. They focus their attention on the main theme of the lesson of a particular nit, that deals with family life. For example, an excerpt from a particular unit may be the 'Understanding of myself and family members'. Most home economics teachers believe that a family setting and/or schools, whether private or public institutions, are appropriate places for productive education. As well, each of these educational settings, should take complete responsibility for teaching morality of education. As a way to activate the morality education, teachers believe that working with the students and understanding the needs of their students, along with the cooperation of parents, are key factors in the teaming process. Another way is the change of teacher's perceptions and educational conditions or environment. Secondly. home economics teachers in middle school. are showing a higher level of understanding on the importance regarding the contents of morality education, which can be noticed through the high level of their teaching performances. Regarding the importance of morality education, the first priority goes to showing respect for parents and the elderly, as well as sexual ethics and respect for life must always be taken into consideration. In regards to the level of teaching performance, the first priority goes to responsibility and co-operation. Secondly. showing respect for parents and the elderly and sexual ethics will be the third. Through data achieved through this study, the majority of home economics education teachers believe that morality education in home economics education is very important and a key factor in their teaching practices.

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Study of Hydrodynamics and Reaction Characteristics of K-based Solid Sorbents for CO2 Capture in a Continuous System Composed of Two Bubbling Fluidized-bed Reactors (두 개의 기포유동층으로 구성된 연속장치에서 CO2 회수를 위한 K-계열 고체흡수제의 수력학적 특성 및 반응특성)

  • Kim, Ki-Chan;Kim, Kwang-Yul;Park, Young Cheol;Jo, Sung-Ho;Ryu, Ho-Jung;Yi, Chang-Keun
    • Korean Chemical Engineering Research
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    • 제48권4호
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    • pp.499-505
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    • 2010
  • In this study, hydrodynamics and reaction characteristic of K-based solid sorbents for $CO_2$ capture were investigated using a continuous system composed of two bubbling fluidized-bed reactors(1.2 m tall bed with 0.11 m i.d.). Potassium-based dry sorbents manufactured by the Korea Electric Power Research Institute were used, which were composed of $K_2CO_3$ of 35% for $CO_2$ absorption and supporters of 65% for mechanical strength. The continuous system consists of two bubbling fluidized-bed reactors, solid injection nozzle, riser, chiller, analyzer and heater for regeneration reaction. The minimum fluidizing velocity of the continuous system was 0.0088 m/s and the solid circulation rate measured was $10.3kg/m^2{\cdot}s$ at 1.05 m/s velocity of the solid injection nozzle. The $CO_2$ concentration of the simulated gas was about 10 vol% in dry basis. Reaction temperature in carbonator and regenerator were maintained about $70^{\circ}C$ and $200^{\circ}C$, respectively. Differential pressures, which were maintained in carbonator and regenerator, were about $415mmH_2O$ and $350mmH_2O$, respectively. In order to find out reaction characteristics of dry sorbents, several experiments were performed according to various experimental conditions such as $H_2O$ content(7.28~19.66%) in feed gas, velocity (0.053~0.103 m/s) of simulated gas, temperature($60{\sim}80^{\circ}C$) of a carbonator, temperature($150{\sim}200^{\circ}C$) of a regenerator and solid circulation rate($7.0{\sim}10.3kg/m^2{\cdot}s$). The respective data of operating variables were saved and analyzed after maintaining one hour in a stable manner. As a result of continuous operation, $CO_2$ removal tended to increase by increasing $H_2O$ content in feed gas, temperature of a regenerator and solid circulation rate and to decrease by increasing temperature of a carbonator and gas velocity in a carbonator.

Reading Deviations of Glass Rod Dosimeters Using Different Pre-processing Methods for Radiotherapeutic in-vivo Dosimetry (유리선량계의 전처리 방법이 방사선 치료 선량 측정에 미치는 영향)

  • Jeon, Hosang;Nam, Jiho;Park, Dahl;Kim, Yong Ho;Kim, Wontaek;Kim, Dongwon;Ki, Yongkan;Kim, Donghyun;Lee, Ju Hye
    • Progress in Medical Physics
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    • 제24권2호
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    • pp.92-98
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    • 2013
  • The experimental verification of treatment planning on the treatment spot is the ultimate method to assure quality of radiotherapy, so in-vivo skin dose measurement is the essential procedure to confirm treatment dose. In this study, glass rod dosimeter (GRD), which is a kind of photo-luminescent based dosimeters, was studied to produce a guideline to use GRDs in vivo dosimetry for quality assurance of radiotherapy. The pre-processing procedure is essential to use GRDs. This is a heating operation for stabilization. Two kinds of pre-processing methods are recommended by manufacturer: a heating method (70 degree, 30 minutes) and a waiting method (room temperature, 24 hours). We equally irradiated 1.0 Gy to 20 GRD elements, and then different preprocessing were performed to 10 GRDs each. In heating method, reading deviation of GRDs at same time were relatively high, but the deviation was very low as time went on. In waiting method, the deviation among GRDs was low, but the deviation was relatively high as time went on. The meaningful difference was found between mean reading values of two pre-processing methods. Both methods present mean dose deviation under 5%, but the relatively high effect by reading time was observed in waiting method. Finally, GRD is best to perform in-vivo dosimetry in the viewpoint of accuracy and efficiency, and the understanding of how pre-processing affect the accuracy is asked to perform most accurate in-vivo dosimetry. The further study is asked to acquire more stable accuracy in spite of different irradiation conditions for GRD usage.

A Dynamic Behavior Evaluation of the Curved Rail according to Lateral Spring Stiffness of Track System (궤도시스템의 횡탄성에 따른 곡선부 레일의 동적거동평가)

  • Kim, Bag-Jin;Choi, Jung-Youl;Chun, Dae-Sung;Eom, Mac;Kang, Yun-Suk;Park, Yong-Gul
    • Proceedings of the KSR Conference
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    • 한국철도학회 2007년도 추계학술대회 논문집
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    • pp.517-528
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    • 2007
  • Domestic or international existing researches regarding rail damage factors are focused on laying, vehicle conditions, driving speed and driving habits and overlook characteristics of track structure (elasticity, maintenance etc). Also in ballast track, as there is no special lateral spring stiffness of track also called as ballast lateral resistance in concrete track, generally, existing study shows concrete track has 2 time shorter life cycle for rail replacement than ballast track due to abrasion. As a result of domestic concrete track design and operation performance review, concrete track elasticity is lower than track elasticity of ballast track resulting higher damage on rail and tracks. Generally, concrete track has advantage in track elasticity adjustment than ballast track and in case of Europe, in concrete track design, it is recommended to have same or higher performance range of vertical elastic stiffness of ballast track but domestically or internationally review on lateral spring stiffness of track is very minimal. Therefore, through analysis of service line track on site measurement and analysis on performance of maintenance, in this research, dynamic characteristic behaviors of commonly used ballast and concrete track are studied to infer elasticity of service line track and experimentally prove effects of track lateral spring stiffness that influence curved rail damage as well as correlation between track elasticity by track system and rail damage to propose importance of appropriate elastic stiffness level for concrete and ballast track.

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Management of plant genetic resources at RDA in line with Nagoya Protocol

  • Yoon, Moon-Sup;Na, Young-Wang;Ko, Ho-Cheol;Lee, Sun-Young;Ma, Kyung-Ho;Baek, Hyung-Jin;Lee, Su-Kyeung;Lee, Sok-Young
    • Proceedings of the Korean Society of Crop Science Conference
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.51-52
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    • 2017
  • "Plant genetic resources for food and agriculture" means any genetic material of plant origin of actual or potential value for food and agriculture. "Genetic material" means any material of plant origin, including reproductive and vegetative propagating material, containing functional units of heredity. (Internal Treaty on Plant Genetic Resources for Food and Agriculture, ITPGRFA). The "Nagoya Protocol on Access to Genetic Resources and the Fair and Equitable Sharing of Benefits Arising from their Utilization (ABS) to the Convention on Biological Diversity (shortly Nagoya Protocol)" is a supplementary agreement to the Convention on Biological Diversity. It provides a transparent legal framework for the effective implementation of one of the three objectives of the CBD: the fair and equitable sharing of benefits arising out of the utilization of genetic resources. The Nagoya Protocol on ABS was adopted on 29 October 2010 in Nagoya, Japan and entered into force on 12 October 2014, 90 days after the deposit of the fiftieth instrument of ratification. Its objective is the fair and equitable sharing of benefits arising from the utilization of genetic resources, thereby contributing to the conservation and sustainable use of biodiversity. The Nagoya Protocol will create greater legal certainty and transparency for both providers and users of genetic resources by; (a) Establishing more predictable conditions for access to genetic resources and (b) Helping to ensure benefit-sharing when genetic resources leave the country providing the genetic resources. By helping to ensure benefit-sharing, the Nagoya Protocol creates incentives to conserve and sustainably use genetic resources, and therefore enhances the contribution of biodiversity to development and human well-being. The Nagoya Protocol's success will require effective implementation at the domestic level. A range of tools and mechanisms provided by the Nagoya Protocol will assist contracting Parties including; (a) Establishing national focal points (NFPs) and competent national authorities (CNAs) to serve as contact points for information, grant access or cooperate on issues of compliance, (b) An Access and Benefit-sharing Clearing-House to share information, such as domestic regulatory ABS requirements or information on NFPs and CNAs, (c) Capacity-building to support key aspects of implementation. Based on a country's self-assessment of national needs and priorities, this can include capacity to develop domestic ABS legislation to implement the Nagoya Protocol, to negotiate MAT and to develop in-country research capability and institutions, (d) Awareness-raising, (e) Technology Transfer, (f) Targeted financial support for capacity-building and development initiatives through the Nagoya Protocol's financial mechanism, the Global Environment Facility (GEF) (Nagoya Protocol). The Rural Development Administration (RDA) leading to conduct management agricultural genetic resources following the 'ACT ON THE PRESERVATION, MANAGEMENT AND USE OF AGRO-FISHERY BIO-RESOURCES' established on 2007. According to $2^{nd}$ clause of Article 14 (Designation, Operation, etc. of Agencies Responsible for Agro-Fishery Bioresources) of the act, the duties endowed are, (a) Matters concerning securing, preservation, management, and use of agro-fishery bioresources; (b) Establishment of an integrated information system for agro-fishery bioresources; (c) Matters concerning medium and long-term preservation of, and research on, agro-fishery bioresources; (d) Matters concerning international cooperation for agro-fishery bioresources and other relevant matters. As the result the RDA manage about 246,000 accessions of plant genetic resources under the national management system at the end of 2016.

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Real Option Analysis to Value Government Risk Share Liability in BTO-a Projects (손익공유형 민간투자사업의 투자위험분담 가치 산정)

  • KU, Sukmo;LEE, Sunghoon;LEE, Seungjae
    • Journal of Korean Society of Transportation
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    • 제35권4호
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    • pp.360-373
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    • 2017
  • The BTO-a projects is the types, which has a demand risk among the type of PPP projects in Korea. When demand risk is realized, private investor encounters financial difficulties due to lower revenue than its expectation and the government may also have a problem in stable infrastructure operation. In this regards, the government has applied various risk sharing policies in response to demand risk. However, the amount of government's risk sharing is the government's contingent liabilities as a result of demand uncertainty, and it fails to be quantified by the conventional NPV method of expressing in the text of the concession agreement. The purpose of this study is to estimate the value of investment risk sharing by the government considering the demand risk in the profit sharing system (BTO-a) introduced in 2015 as one of the demand risk sharing policy. The investment risk sharing will take the form of options in finance. Private investors have the right to claim subsidies from the government when their revenue declines, while the government has the obligation to pay subsidies under certain conditions. In this study, we have established a methodology for estimating the value of investment risk sharing by using the Black - Scholes option pricing model and examined the appropriateness of the results through case studies. As a result of the analysis, the value of investment risk sharing is estimated to be 12 billion won, which is about 4% of the investment cost of the private investment. In other words, it can be seen that the government will invest 12 billion won in financial support by sharing the investment risk. The option value when assuming the traffic volume risk as a random variable from the case studies is derived as an average of 12.2 billion won and a standard deviation of 3.67 billion won. As a result of the cumulative distribution, the option value of the 90% probability interval will be determined within the range of 6.9 to 18.8 billion won. The method proposed in this study is expected to help government and private investors understand the better risk analysis and economic value of better for investment risk sharing under the uncertainty of future demand.

The Development of On-Line Statistics Program for Radiation Oncology (방사선종양학과 On-line 통계처리프로그램의 개발)

  • Kim Yoon-Jong;Lee Dong-Hoon;Ji Young-Hoon;Lee Dong-Han;Jo Chul-Ku;Kim Mi-Sook;Ru Sung-Rul;Hong Seung-Hong
    • Radiation Oncology Journal
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    • 제19권4호
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    • pp.369-380
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    • 2001
  • Purpose : By developing on-line statistics program to record the information of radiation oncology to share the information with internet. It is possible to supply basic reference data for administrative plans to improve radiation oncology. Materials and methods : The information of radiation oncology statistics had been collected by paper forms about 52 hospitals in the past. Now, we can input the data by internet web browsers. The statistics program used windows NT 4.0 operation system, Internal Information Server 4.0 (IIS4.0) as a web server and the Microsoft Access MDB. We used Structured Query Language (SQL), Visual Basic, VBScript and JAVAScript to display the statistics according to years and hospitals. Results : This program shows present conditions about man power, research, therapy machines, technics, brachytherapy, clinic statistics, radiation safety management, institution, quality assurance and radioisotopes in radiation oncology department. The database consists of 38 inputs and 6 outputs windows. Statistical output windows can be increased continuously according to user's need. Conclusion : We have developed statistics program to process all of the data in department of radiation oncology for reference information. Users easily could input the data by internet web browsers and share the information.

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Fate of Heavy Metals in Activated Sludge: Sorption of Heavy Metal ions by Nocardia amarae

  • Kim, Dong-wook
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 한국환경과학회 1998년도 가을 학술발표회 프로그램
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    • pp.2-4
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    • 1998
  • Proliferation of Nocardia amarae cells in activated sludge has often been associated with the generation of nuisance foams. Despite intense research activities in recent years to examine the causes and control of Nocardia foaming in activated sludge, the foaming continued to persist throughout the activated sludge treatment plants in United States. In addition to causing various operational problems to treatment processes, the presence of Nocardia may have secondary effects on the fate of heavy metals that are not well known. For example, for treatment plants facing more stringent metal removal requirements, potential metal removal by Nocardia cells in foaming activated sludge would be a welcome secondary effect. In contrast, with new viosolid disposal regulations in place (Code o( Federal Regulation No. 503), higher concentration of metals in biosolids from foaming activated sludge could create management problems. The goal of this research was to investigate the metal sorption property of Nocardia amarae cells grown in batch reactors and in chemostat reactors. Specific surface area and metal sorption characteristics of N. amarae cells harvested at various growth stages were compared. Three metals examined in this study were copper, cadmium and nickel. Nocardia amarae strain (SRWTP isolate) used in this study was obtained from the University of California at Berkeley. The pure culture was grown in 4L batch reactor containing mineral salt medium with sodium acetate as the sole carbon source. In order to quantify the sorption of heavy metal ions to N amarae cell surfaces, cells from the batch reactor were harvested, washed, and suspended in 30mL centrifuge tubes. Metal sorption studies were conducted at pH 7.0 and ionlc strength of 10-2M. The sorption Isotherm showed that the cells harvested from the stationary and endogenous growth phase exhibited significantly higher metal sorption capacity than the cells from the exponential phase. The sequence of preferential uptake of metals by N. amarae cells was Cu>Cd>Ni. The specific surFace area of Nocardia cells was determined by a dye adsorption method. N.amarae cells growing at ewponential phase had significantly less specific surface area than that of stationary phase, indicating that the lower metal sorption capacity of Nocardia cells growing at exponential phase may be due to the lower specific surface area. The growth conditions of Nocardia cells in continuous culture affect their cell surface properties, thereby governing the adsorption capacity of heavy metal. The comparison of dye sorption isotherms for Nocardia cells growing at various growth rates revealed that the cell surface area increased with increasing sludge age, indicating that the cell surface area is highly dependent on the steady-state growth rate. The highest specific surface area of 199m21g was obtained from N.amarae cell harvested at 0.33 day-1 of growth rate. This result suggests that growth condition not only alters the structure of Nocardia cell wall but also affects the surface area, thus yielding more binding sites of metal removal. After reaching the steady-state condition at dilution rate, metal adsorption isotherms were used to determine the equilibrium distributions of metals between aqueous and Nocardia cell surfaces. The metal sorption capacity of Nocardia biomass harvested from 0.33 day-1 of growth rate was significantly higher than that of cells harvested from 0.5- and 1-day-1 operation, indicatng that N.amarae cells with a lower growth rate have higher sorpion capacity. This result was in close agreement with the trend observed from the batch study. To evaluate the effect of Nocardia cells on the metal binding capacity of activated sludge, specific surface area and metal sorption capacity of the mixture of Nocardia pure cultures and activated sludge biomass were determined by a series of batch experiments. The higher levels of Nocardia cells in the Nocardia-activated sludge samples resulted in the higher specific surface area, explaining the higher metal sorption sites by the mixed luquor samples containing greater amounts on Nocardia cells. The effect of Nocardia cells on the metal sorption capacity of activated sludge was evaluated by spiking an activated sludge sample with various amounts of pre culture Nocardia cells. The results of the Langmuir isotherm model fitted to the metal sorption by various mixtures of Nocardia and activated sludge indicated that the mixture containing higher Nocardia levels had higher metal adsorption capacity than the mixture containing lower Nocardia levels. At Nocardia levels above 100mg/g VSS, the metal sorption capacity of activate sludge increased proportionally with the amount of Noeardia cells present in the mixed liquor, indicating that the presence of Nocardia may increase the viosorption capacity of activated sludge.

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Analysis on the Characteristics of Ventilation and Cooling for Greenhouses Constructed in Reclaimed Lands (간척지 온실의 환기 및 냉방 특성 분석)

  • Nam, Sang-Woon;Shin, Hyun-Ho
    • Journal of Bio-Environment Control
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    • 제26권3호
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    • pp.181-187
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    • 2017
  • The purpose of this study was to provide basic data for development of environmental design technology for greenhouses constructed in reclaimed lands. The climatic conditions around seven major reclaimed land areas with a plan to install advanced horticultural complexes in Korea were analyzed. The characteristics of natural ventilation and temperature rise through the thermal environment measurement of the greenhouse in Saemangeum were analyzed. The part to be applied to the environmental design of the greenhouses in reclaimed lands were reviewed. Results of comparing the ventilation rate of the greenhouse according to the presence or absence of plants showed the greenhouse with plants had the lower ventilation rate, but the smaller rise of indoor temperature due to the evapotranspiration of plants. In the greenhouse with plants, the number of air changes was in the range of 0.3 to 0.9 volumes/min and the average was 0.7 volumes/min. The rise of indoor temperature relative to outdoor temperature was in the range of 1 to $5^{\circ}C$ and the average $2.5^{\circ}C$. The natural ventilation performance of the experimental greenhouse constructed in the reclaimed land almost satisfied the recommended ventilation rate in summer and the rise of indoor temperature relative to outdoor temperature did not deviate considerably from the cultivation environment of plants. Therefore, it was determined that the greenhouse cultivation in Saemangeum reclaimed land is possible with only natural ventilation systems without cooling facilities. As the reclaimed land is located in the seaside, the wind is stronger than the inland area, and the fog is frequent. This strong wind speed increases the ventilation rate of greenhouses, which is considered to be a factor for reducing the cooling load. In addition, since the fog duration is remarkably longer than that of inland area, the seasonal cooling load is expected to decrease, which is considered to be advantageous in terms of the operation cost of cooling facilities.