• Title/Summary/Keyword: Weather conditions

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Assessment on Yield Decrease of Kimchi Cabbage by Extreme Weather Conditions using Physiological Parameters (생리적 요인 활용 이상기상에 의한 배추의 수량저하 평가)

  • Lee, Hee Ju;Lee, Sang Gyu;Kim, Sung Kyeom;Park, Sung Tae
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.20 no.1
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    • pp.127-134
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    • 2018
  • This study evaluated the effects of high air temperature and waterlogging duration on growth and yield of Kimchi cabbage. Air temperature treatments were applied with ventilation; optimal (set $20^{\circ}C$) and delayed ($30^{\circ}C$) in the greenhouses. The waterlogging treatment levels were implicated 0, 12, 24, 48, and 72 hours, respectively. The growth of Kimchi cabbage was significantly affected by waterlogging duration. The head weight decreased by combining severe waterlogging and high air temperature. Net photosynthetic rate under the combination of non-waterlogging and optimal air temperature was $22.6{\mu}mol\;CO_2{\cdot}m^{-2}{\cdot}s^{-1}$, which was the greatest, while that of 72 hours-waterlogging was rapidly decreased. The percentage of formality with 0, 12, and 24 hours-waterlogging was over 88%, however, those of 72 hours-waterlogging with optimal and delayed ventilation were 64 and 68%, respectively, which were dramatically reduced. The yields were more affected by waterlogging duration than air temperature treatment because of deducting as increased waterlogging periods. These results indicate that waterlogging treatment reduced the yield and quality of Kimchi cabbage, thus it will be feasible to enhance the harvest time when severe waterlogging in the field.

Range Design of Pulse Repetition Frequency for Removal of SAR Residual Image (영상레이더 잔상 제거를 위한 펄스 반복 주파수의 범위 설계)

  • Kim, Kyeong-Rok;Heo, Min-Wook;Kim, Tu-Hwan;Ryu, Sang-Burm;Lee, Sang-Gyu;Lee, Hyeon-Cheol;Kim, Jae-Hyun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.11
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    • pp.1653-1660
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    • 2016
  • The synthetic aperture rardar (SAR) is an active sensor using microwaves. It transmits a microwave signal, called a chirp pulse, and receives the reflected signal in a moving platform such as satellite and unmanned aerial vehicle. Since this sensor uses microwaves that can penetrate the atmosphere, SAR generates the images regardless of light and weather conditions. However SAR operates on the moving platform, the Doppler shift and the side-looking observation method should be considered. In addtion, a residual image or ghost image can be occurred according to selection of the pulse repetition frequency (PRF). In this paper, a range design of the PRF for the L-band spaceborne SAR system is studied for prevention of SAR image distortion. And the system is studied for prevention of SAR image distortion. And the system parameter and the PRF are calibrated iteratively according to the proposed system design procedure and design constraints. The MATLAB based on SAR system simulator has been developed to verify the validity of calculated PRF. The developed simulator assumes that SAR sensor is operated by the PRF calculated from the design. The results of the simulator show that the targets in image has a valid peak to side-lobe ratio (PSLR) so that the PRF can be used for the spaceborne SAR sensor.

Effects of Seeding and Organic Fertilizer Rates and Harvest time on Kenaf Yield and Feed Value (파종량, 유기질 비료 시용량 및 수확시기에 따른 케나프의 수량 및 사료가치)

  • Nam, Cheol Hwan;Kim, Ki Soo;Park, Man Ho;Kim, Won Ho;Ji, Hee Jung;Choi, Ki Chun;Sun, Sang Soo
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.38 no.2
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    • pp.91-98
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    • 2018
  • This study was conducted in 2014 in the Gangjin area of Jeonnam province for the purpose of confirming the potential of Kenaf as an alternative feed crop of rice. The weather and soil conditions were favorable and there was no adverse effect on the growth of Kenaf. The amount of seeding was given at 10 kg, 15 kg and 20 kg. As the seeding volume increased, plant height and dry matter yield increased, and stem diameter and number of nodes decreased. The highest growth rate was observed between 75 and 90 days from the date of planting(p<0.05). As the growth progressed, stem rate increased and leaf rate decreased(p<0.05). Increased amount of seeding and growth resulted in decreased CP and TDN and increased ADF and NDF, which resulted in the decreased economic value of Kenaf as a feed crop. The result of increasing the use of organic fertilizer to 20 kg and 30 kg was similar to increasing the amount of seeding. As organic fertilizer usage increased, dry matter yield and growth rate improved(p<0.05).

A Study on the Environmental Application of Image Radar for Expanding the Use of Next Generation Medium Satellite 5 (차세대중형위성 5호 활용 확대를 위한 영상레이더의 환경분야 활용 방안 연구)

  • Han, Hyeon-gyeong;Lee, Moungjin
    • Korean Journal of Remote Sensing
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    • v.35 no.6_3
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    • pp.1251-1260
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    • 2019
  • Existing environmental spatial information, which has been concentrated on spatial resolution, has limitations in solving realistic environmental problems that must be accompanied by physical and chemical characterization. Accordingly, there is a need for an image radar capable of identifying physical characteristics of an object regardless of weather conditions, day and night, and sunlight. Image radar is used in various fields in the United States and Europe. The next generation of medium-sized satellite No. 5 in Korea, which is under development with the aim of monitoring water disasters, is also looking for ways to expand the scope to various applications based on the existing application range. To this end, we analyzed domestic and international papers (100 works) using image radar, and reviewed KEI 2016 report, domestic papers, and foreign papers. Based on this, various environmental issues were summarized and the effects of when the image radar was used were analyzed and land cover was selected as an environmental issue. In the future, we will embody the technology to improve the accuracy of the land cover map, which is the environmental issue selected in this study, and build the foundation system for the stable use of the land cover map.

A Study of the Urban Tree Canopy Mean Radiant Temperature Mitigation Estimation (도시림의 여름철 평균복사온도 저감 추정 연구)

  • An, Seung Man;Son, Hak-gi;Lee, Kyoo-Seock;Yi, Chaeyeon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.1
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    • pp.93-106
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    • 2016
  • This study aimed to estimate and evaluate the thermal mitigation of the urban tree canopy on the summer outdoor environment by quantitative use of mean radiant temperature. This study applied the SOLWEIG model based $T_{mrt}$ comparison method by using both (1) urban tree canopy presence examples and (2) urban tree canopy absence examples as constructed from airborne LiDAR system based three-dimensional point cloud data. As a result, it was found that an urban tree canopy can provide a decrease in the entire domain averaged daily mean $T_{mrt}$ about $5^{\circ}C$ and that the difference can increase up to $33^{\circ}C$ depending both on sun position and site conditions. These results will enhance urban microclimate studies such as indices (e.g., wind speed, humidity, air temperature) and biometeorology (e.g., perceived temperature) and will be used to support forest based public green policy development.

A Study on Developing A Design of Package Air Conitioner For Home use-With a Focus on Goldstar Co Package Air conditioner (가정용 PACKAGE AIR CONDITIONER 디자인 개발에 관한 연구-(주) 금성사 PAC를 중심으로-)

  • 오성진
    • Archives of design research
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    • v.13
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    • pp.153-162
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    • 1996
  • The residence space has been in the trend of being expanded with the J'l'cent economic growth Therefore PAC may be said to have [wen from business use to home US(: the progressed living standard as the goods ior Uw "ummel' S('dSOn rest'ntly though sold in Uw fast for mainly buslTw"s use. PAC has been in the demand day ;lner day and in the tn'nd on the bc,ing the necessJty of the n'sent wf',lther warming phenomenon This study is the case study nf the products development and design process of PAC which has bpcn llrivcn and developed by Gold Star Co. ,Ltd. Which .is the firm for home electric appliances representing Korea. This studies for the development and the design of the products by the firm thus emphasizing the visulizing it based on this study. For example as they being the goods for the summer season I have tried to know the physical quakity and the characters of koreans by the weather conditions and estimated the demand by setting up the target customers of the PAC as the customers' environment. And I analyzed the acts in the living room in the apartments as the living envinorment which has the direct relation with PAC and also became a help to the moulding work of PAC by analyzing the complete interior image in the living room. In the practical moulding work the Design concept was classified into the envinorment of customer, living and products to drive as the below. Firstly - New shape (Round slim) has been realized which leads the minimizing the moulding space and visul sense of opening as its being spacious. The 2nd - the high class sense of the products which are harmonious with the atmosphere of the living room by making it interiorized has been visible. The 3rd - The shape stimulating the sensitivity of the users and surface treatment are emphasized by making it be touched. The 4th - During inviting use of technology image which appears in the electronics products are attemptedby making it be high quality.king it be high quality.

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Compressive Strength and Chloride Permeability of High Strength Concrete according to the Variety of Mineral Admixtures (광물질혼화재 종류별 고강도콘크리트의 압축강도 및 촉진 염소이온침투 특성)

  • Moon Han-Young;Kim Byoung-Kwon
    • Journal of the Korea Concrete Institute
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    • v.16 no.3 s.81
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    • pp.407-414
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    • 2004
  • The purpose of this study is to evaluate the ability to resist chloride ions penetration of the concrete structure under marine environment in south-east asia especially. In this study, high strength concrete(HSC) with various combination of ordinary portland cement(OPC), blast-furnace slag(SG) and silica fume(SF) are cured 23 and $35^{\circ}C$ considering the site weather, and are cured in water for 3, 7 or 56 days respectively. And to investigate the fundamental properties and the resistance of chloride penetration of various HSC, setting time, slump flow, compressive strength, void and ASTM C 1202 test were conducted. Test results show that the compressive strength of HSC is similar regardless of SG replacement ratio and total charge passed of chloride is the smallest at 40% replacement of SG. The compressive strength of G4FS HSC is, besides, outstandingly high at early age compare with other HSC, but the compressive strength of G4F HSC, which is vary according to curing temperature and condition, most high at the age after 7 days. Total passed charge of HSC get larger in the order G4FS

Cause-based Categorization of the Riparian Vegetative Recruitment and Corresponding Research Direction (하천식생 이입현상의 원인 별 유형화 및 연구 방향)

  • Woo, Hyoseop;Park, Moonhyeong
    • Ecology and Resilient Infrastructure
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    • v.3 no.3
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    • pp.207-211
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    • 2016
  • This study focuses on the categorization of the phenomenon of vegetative recruitment on riparian channels, so called, the phenomenon from "white river" to "green river", and proposes for the corresponding research direction. According to the literature review and research outputs obtained from the authors' previous research performed in Korea within a limited scope, the necessary and sufficient conditions for the recruitment and retrogression of riparian vegetation may be the mechanical disturbance (riverbed tractive stress), soil moisture (groundwater level, topography, composition of riverbed material, precipitation etc.), period of submergence, extreme weather, and nutrient inflow. In this study, two categories, one for the reduction in spring flood due to the change in spring precipitation pattern in unregulated rivers and the other for the increase in nutrient inflow into streams, both of which were partially proved, have been added in the categorization of the vegetative recruitment and retrogression on the riparian channels. In order to scientifically investigate further the phenomenon of the riparian vegetative recruitment and retrogression and develop the working riparian vegetative models, it is necessary to conduct a systematic nationwide survey on the "white to green" rivers, establishment of the categorization of the vegetation recruitment and retrogression based on the proof of those hypotheses and detailed categorization, development of the working mathematical models for the dynamic riparian vegetative recruitment and retrogression, and adaptive management for the river changes.

A Study on the Establishment of Typhoon Context Awareness Information through Analysis of Disaster Cases (재난사례 분석을 통한 태풍 상황인지정보 구축방안 연구)

  • Park, Jinyi;Kim, OkJu;Lee, JunWoo;Lee, SangKwon
    • Journal of the Society of Disaster Information
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    • v.16 no.3
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    • pp.430-439
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    • 2020
  • Purpose: As the frequency of impact typhoons increases and the form of damage becomes more complicated, the need for information to help disaster response workers recognize the typhoon situation in advance is growing. In this study, Definitions and implementation measures for information utilized at each stage of the task were proposed in carrying out typhoon response tasks that occur every year. Method: In 2019, the government classified information that was used for each step of work and conducted analysis on necessary information for the situation. Based on the analyzed information, typhoon status information was established through an opinion survey by central and local government officer. Result: The task of typhoon situations was the most important part of monitoring weather conditions and sharing damage situations, and the information utilized was analyzed to require information derived through the convergence of historical and situation information. Conclusion: As the correlation between work and information between the response departments increases as the typhoon situation progresses, information about typhoon situation should be applied to the actual typhoon situation in the future to enhance information and establish a related system.

Fundamentals of Ecotoxicity Evaluation Methods using Domestic Aquatic Organisms in Korea : (I) Fish (국내 생물종을 이용한 생태독성평가 기반연구 : (I) 어류)

  • Nam, Sun-Hwa;Yang, Chang-Yong;An, Youn-Joo;Lee, Jae-Kwan
    • Korean Journal of Ecology and Environment
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    • v.40 no.2
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    • pp.173-183
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    • 2007
  • The Ministry of Environment plans to introduce the Whole Effluent Toxicity (WET) system in Korea. The WET test is well established in developed countries with recognizing of the limitations of physicochemical analysis method and potential risk of chemicals in water medium. Therefore, it is essential to build the ecotoxicity infrastructure for the induction of WET test. In this study, we extensively collected the domestic and foreign toxicity test methods which employ native test species to Korea. And we suggested that the domestic ecotoxicity test methods with domestic test species in Korea through extracting the range of test conditions. Five domestic fish species selected were Carassiu auratus (Crucian carp), Cyprinus carpio(Common carp), Gasterosteus aculeatus (Three spine stickleback), Misgurnus anguillicaudatus (Oriental weather fish) and Oryzias latipes (Japanese medaka), The toxicity test methods with native test species to Korea were collected from the standard methods (OECD, U.S. EPA, ASTM), government reports, SCI papers and domestic papers. We collected the 32 test methods, and suggested the suitable aquatic toxicity test methods for fish. It is expected that this study could prove a useful information to establish the ecotoxicity test methods with domestic aquatic organisms in Korea henceforth.