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A Study on Determination of Consumptive Use Needed in the Vegetable Plots for the Prevention of Drought Damage (고등채소의 한해를 방지하기 위한 포장 용수량 결정에 관한연구)

  • 최예환
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.15 no.2
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    • pp.2949-2967
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    • 1973
  • The purpose of this study is to find out and determine the minimum consumptive use of water for Korean cabbage and turmp, so that the minimum water requirement can be secured always for a stable cultivation of these vegetables regardless of weather conditions. The experiment was conducted in two periods; first one from May to July and second one from August to October, each experiment with two varieties of cabbage and two varieties of radish with 2 replicants and 15 treatments. The results found from the above are briefly as follows: 1. Since the mean soil moisture equivalent 64 days after the treatment was 28.5% and the soil moisture content at the time was 2.67% which is far less than that of the wilting point, the crop seemed to be extremely caused by a drought. 2. The rate of 51 days after the seeding, soil moisture content of plot No.2 where irrigation has been continuous was the highest or 21.3%, whereas the plot No.14 without irrigations was 11.2% and the lowest. Therefore, the soil moisture content for the minimum qrowth seemed to be 20%. 3. The consumptive coefficient of Blaney and Criddle on cabbage in two periods were K=1.14 and 0.97 respectively, and on radish in two periods were K=1.06 and 0.86 respectively, thus, cabbage was higher than radish. The consumptive coefficient in the first experiment (May-July) was 0.17 to 0.20 higher than the 2nd experiment(August-October). 4. Nomally, cabbage and radish germinate within one week, however, the germination ot these crops which were treated with a suspended water supply from the beginning took two full weeks. 5. When it elapsed 30 days after seeding, the conditions in plot 1,2 and 3 were fairly good however, the crops in the plops other than these showed a withering and the leaves were withered and changed into high green due to an extrem drought. Though it was about same at the beginning, the drought damage on cabbage was worse than that on radish period, and the reasos for this appears in the latter that the roots are grown too deep. 6. The cabbage showed a high affinity between treated plots and varieties. Consequently, it can be said that cabbage is very suseptive to drought damage, and the yield showed a difference of 35% to 56% depending on the selection oe varieties. 7. The radish also showed a high affinity between the treated plots, however, almost us affinity existed between varieties. Therfore, the yield of radish largely depends on the extent of drought, and the selection of variety does not affect at all. 8. The normal consumptive use on cabbage is $0.62{\ell}/sec$, while that on radish is $0.64{\ell}/sec$, and the minimum optimum water requirement that was obtained in this study is $4,000cc/day/m^3$ or $0.462{\ell}/sec/ha$.

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The Role of the Soft Law for Space Debris Mitigation in International Law (국제법상 우주폐기물감축 연성법의 역할에 관한 연구)

  • Kim, Han-Taek
    • The Korean Journal of Air & Space Law and Policy
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    • v.30 no.2
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    • pp.469-497
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    • 2015
  • In 2009 Iridium 33, a satellite owned by the American Iridium Communications Inc. and Kosmos-2251, a satellite owned by the Russian Space Forces, collided at a speed of 42,120 km/h and an altitude of 789 kilometers above the Taymyr Peninsula in Siberia. NASA estimated that the satellite collision had created approximately 1,000 pieces of debris larger than 10 centimeters, in addition to many smaller ones. By July 2011, the U.S. Space Surveillance Network(SSN) had catalogued over 2,000 large debris fragments. On January 11, 2007 China conducted a test on its anti-satellite missile. A Chinese weather satellite, the FY-1C polar orbit satellite, was destroyed by the missile that was launched using a multistage solid-fuel. The test was unprecedented for having created a record amount of debris. At least 2,317 pieces of trackable size (i.e. of golf ball size or larger) and an estimated 150,000 particles were generated as a result. As far as the Space Treaties such as 1967 Outer Space Treaty, 1968 Rescue Agreement, 1972 Liability Convention, 1975 Registration Convention and 1979 Moon Agreement are concerned, few provisions addressing the space environment and debris in space can be found. In the early years of space exploration dating back to the late 1950s, the focus of international law was on the establishment of a basic set of rules on the activities undertaken by various states in outer space.. Consequently environmental issues, including those of space debris, did not receive the priority they deserve when international space law was originally drafted. As shown in the case of the 1978 "Cosmos 954 Incident" between Canada and USSR, the two parties settled it by the memorandum between two nations not by the Space Treaties to which they are parties. In 1994 the 66th conference of International Law Association(ILA) adopted "International Instrument on the Protection of the Environment from Damage Caused by Space Debris". The Inter-Agency Space Debris Coordination Committee(IADC) issued some guidelines for the space debris which were the basis of "the UN Space Debris Mitigation Guidelines" which had been approved by the Committee on the Peaceful Uses of Outer Space(COPUOS) in its 527th meeting. On December 21 2007 this guideline was approved by UNGA Resolution 62/217. The EU has proposed an "International Code of Conduct for Outer Space Activities" as a transparency and confidence-building measure. It was only in 2010 that the Scientific and Technical Subcommittee began considering as an agenda item the long-term sustainability of outer space. A Working Group on the Long-term Sustainability of Outer Space Activities was established, the objectives of which include identifying areas of concern for the long-term sustainability of outer space activities, proposing measures that could enhance sustainability, and producing voluntary guidelines to reduce risks to long-term sustainability. By this effort "Guidelines on the Long-term Sustainability of Outer Space Activities" are being under consideration. In the case of "Declaration of Legal Principles Governing the Activities of States in the Exp1oration and Use of Outer Space" adopted by UNGA Resolution 1962(XVIII), December 13 1963, the 9 principles proclaimed in that Declaration, although all of them incorporated in the Space Treaties, could be regarded as customary international law binding all states considering the time and opinio juris by the responses of the world. Although the soft law such as resolutions, guidelines are not binding law, there are some provisions which have a fundamentally norm-creating character and customary international law. In November 12 1974 UN General Assembly recalled through a Resolution 3232(XXIX) "Review of the role of International Court of Justice" that the development of international law may be reflected, inter alia, by the declarations and resolutions of the General Assembly which may to that extend be taken into consideration by the judgements of the International Court of Justice. We are expecting COPUOS which gave birth 5 Space Treaties that it could give us binding space debris mitigation measures to be implemented based on space debris mitigation soft law in the near future.

Impacts of Climate Change on Rice Production and Adaptation Method in Korea as Evaluated by Simulation Study (생육모의 연구에 의한 한반도에서의 기후변화에 따른 벼 생산성 및 적응기술 평가)

  • Lee, Chung-Kuen;Kim, Junwhan;Shon, Jiyoung;Yang, Woon-Ho;Yoon, Young-Hwan;Choi, Kyung-Jin;Kim, Kwang-Soo
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.14 no.4
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    • pp.207-221
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    • 2012
  • Air temperature in Korea has increased by $1.5^{\circ}C$ over the last 100 years, which is nearly twice the global average rate during the same period. Moreover, it is projected that such change in temperature will continue in the 21st century. The objective of this study was to evaluate the potential impacts of future climate change on the rice production and adaptation methods in Korea. Climate data for the baseline (1971~2000) and the three future climate (2011~2040, 2041~2070, and 2071~2100) at fifty six sites in South Korea under IPCC SRES A1B scenario were used as the input to the rice crop model ORYZA2000. Six experimental schemes were carried out to evaluate the combined effects of climatic warming, $CO_2$ fertilization, and cropping season on rice production. We found that the average production in 2071~2100 would decrease by 23%, 27%, and 29% for early, middle, and middle-late rice maturing type, respectively, when cropping seasons were fixed. In contrast, predicted yield reduction was ~0%, 6%, and 7%, for early, middle, and middle-late rice maturing type, respectively, when cropping seasons were changed. Analysis of variation suggested that climatic warming, $CO_2$ fertilization, cropping season, and rice maturing type contributed 60, 10, 12, and 2% of rice yield, respectively. In addition, regression analysis suggested 14~46 and 53~86% of variations in rice yield were explained by grain number and filled grain ratio, respectively, when cropping season was fixed. On the other hand, 46~78 and 22~53% of variations were explained respectively with changing cropping season. It was projected that sterility caused by high temperature would have no effect on rice yield. As a result, rice yield reduction in the future climate in Korea would resulted from low filled grain ratio due to high growing temperature during grain-filling period because the $CO_2$ fertilization was insufficient to negate the negative effect of climatic warming. However, adjusting cropping seasons to future climate change may alleviate the rice production reduction by minimizing negative effect of climatic warming without altering positive effect of $CO_2$ fertilization, which improves weather condition during the grain-filling period.

Study of BiJeung by 18 doctors - Study of II - (18인(人)의 비증(痺證) 논술(論述)에 대(對)한 연구(硏究) - 《비증전집(痺證專輯)》 에 대(對)한 연구(硏究) II -)

  • Sohn, Dong Woo;Oh, Min Suk
    • Journal of Haehwa Medicine
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    • v.9 no.1
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    • pp.595-646
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    • 2000
  • I. Introduction Bi(痺) means blocking. BiJeung is one kind of symptoms making muscles, bones and jonts feel pain, numbness or edema. For example it can be gout or SLE etc. says that Bi is combination of PungHanSeup. And many doctors said that BiJeung is caused by food, fatigue, sex, stress and change of weather. Therefore we must treat BiJeung by character of patients and characteristic of the disease. Many famous doctors studied medical science by their fathers or teachers. So the history of medical science is long. So I studied ${\ll}Bijeungjujip{\gg}$. II. Final Decision 1. JoGeumTak(趙金鐸) devided BiJeung into Pung, Han, Seup and EumHeo, HeulHeo, YangHeo, GanSinHeo by charcter or reaction of pain. And he use DaeJinGyoTang, GyegiGakYakJiMoTang, SamyoSan, etc. 2. JangPaeGyeu(張沛圭) focused on division of HanYeol(寒熱; coldness and heat) in spite of complexity of BiJeung. He also used insects for treatment. They are very useful for treatment of BiJeung because they can remove EoHyeol(瘀血). 3. SeolMaeng(薛盟) said that the actual cause of BiJeung is Seup. So he thought that BiJeung can be divided into PungSeup, SeupYeol, HanSeup. And he established 6 rules to treat BiJeung and he studied herbs. 4. JangGi(張琪) introduced 10 prescriptions and 10 rules to cure BiJeung. The 1st prescription is for OyeSa, 2nd for internal Yeol, 3rd for old BiJeung, 4th for Soothing muscles, 5th for HanSeup, 6th for regular BiJeung, 7th for functional disorder, 8th for YeolBi, 9th for joint pain and 10th for pain of lower limb. 5. GangSeYoung(江世英) used PungYeongTang(風靈湯) for the treatment of PungBi, OGyeHeukHoTang(烏桂黑虎湯) for HanBi, BangGiMokGwaTang(防己木瓜湯) for SeupBi, YeolBiTang(熱痺湯) for YeolBi, WoDaeRyeokTang(牛大力湯) for GiHei, HyeolPungGeunTang(血楓根湯) for HyeolHeo, ToJiRyongTang(土地龍湯) for the acute stage of SeupBi, OJoRyongTang(五爪龍湯) for the chronic stage of SeupBi, and so on. 6. ShiGeumMook(施今墨) devided BiJeung into four types. They are PungSeupYeol, PungHanSeup, GiHyeolSil(氣血實) and GiHyeolHeo(氣血虛). And he introduced the eight rules of the treatment(SanPun(散風), ChukHan(逐寒), GeoSeuP(, CheongYeol(淸熱), TongRak(通絡), HwalHyeol(活血), HaengGi(行氣), BoHeo(補虛)). 7. WangYiYou(王李儒) explained the acute athritis and said that it can be applicable to HaneBi(行痺). And he used GyeJiJakYakJiMoTang(桂枝芍蘂知母湯) for HanBi and YeolBiJinTongTang(熱痺鎭痛湯) for YeolBi. 8. JangJinYeo(章眞如) said that YeolBi is more common than HanBi. The sympthoms of YeolBi are severe pain, fever, dried tongue, insomnia, etc. And he devided YeolBi into SilYeol and HeoYeol. In case of SilYeol, he used GyeoJiTangHapBaekHoTang(桂枝湯合白虎湯) and in case of HeoYeol he used JaEumYangAekTang(滋陰養液湯). 9. SaHaeJu(謝海洲) introduced three important rules of treatment and four appropriate rules of treatment of BiJeung. 10. YouDoJu(劉渡舟) said that YeolBi is more common than HanBi. He used GaGamMokBanGiTang(加減木防已湯) for YeolBi, GyeJiJakYakJiMoTang or GyeJiBuJaTang(桂枝附子湯) for HanBi and WooHwangHwan(牛黃丸) for the joint pain. 11. GangYiSon(江爾遜) focused on the internal cause. The most important internal cause is JeongGiHeo(正氣虛). So he tried to treat BiJeung by means of balance of Gi and Hyeol. So he ususlly used ODuTang(烏頭湯) and SamHwangTang(三黃湯) for YeolBi, OJeokSan(五積散) for HanBi, SamBiTang(三痺湯) for the chronic BiJeung. 12. HoGeonHwa(胡建華) said that to distinguish YeolBi from Hanbi is very difficult. So he used GyeJiJakYakJiMoTang in case of mixture of HanBi and YeoBi. 13. PiBokGo(畢福高) said that the most common BiJeung is HanBi. He usually used acupuncture with medicine. He followed the theory of EumYongHwa(嚴用和)-he focused on SeonBoHuSa(先補後瀉). 14. ChoiMunBin(崔文彬) used GeoPungHwalHyeolTang(祛風活血湯) for HanBi, SanHanTongRakTang(散寒通絡湯) for TongBi(痛痺), LiSeupHwaRakTang(利濕和絡湯) for ChakBi(着痺), CheongYeolTongGyeolChukBiTang(淸熱通經逐痺湯) for YeolBi(熱痺) and GeoPungHwalHyeolTang(祛風活血湯) for PiBi(皮痺). 15. YouleokSeon(劉赤選) introduced the common principle for the treatment of BiJeung. He used HaePuneDeungTang(海風藤湯) for HaengBi(行痺), SinChakTang(腎着湯), DokHwalGiSaengTang(獨活寄生湯) for TongBi(痛痺), TongPungBang(痛風方) for ChakBi(着痺) and SangGiYiMiTangGaYeongYangGakTang(桑枝苡米湯加羚羊角骨) for YeolBi(熱痺). 16. LimHakHwa(林鶴和) said about TanTan(movement disorders or numbness) and devided TanTan into the acute stage and the chronic stage. He used acupuncture at the meridian spot like YeolGyeol(列缺), HapGok(合谷), etc. And he also used MaHwangBuJaSeSinTang(麻黃附子細辛湯) in case of the acute stage. In the chronic stage he used BangPungTang(防風湯). 17. JinBaekGeun(陳伯勤) liked to use three rules(HwaHyeol(活血), ChiDam(治痰), BoSin(補腎)) to treat BiJeung. He used JinTongSan(鎭痛散) for the purpose of HwalHyeol(活血), SoHwalRakDan(小活絡丹) for ChiDam(治痰) and DokHwalGiSaengTang(獨活寄生湯) for BoSin(補腎). 18. YimGyeHak(任繼學) focused on YangHyeolJoGi(養血調氣) if the stage of BiJeung is chronic. And in the chronic stage he insisted on not using GalHwal(羌活), DokHwal(獨活) and BangPung(防風).

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A Thermal Time-Driven Dormancy Index as a Complementary Criterion for Grape Vine Freeze Risk Evaluation (포도 동해위험 판정기준으로서 온도시간 기반의 휴면심도 이용)

  • Kwon, Eun-Young;Jung, Jea-Eun;Chung, U-Ran;Lee, Seung-Jong;Song, Gi-Cheol;Choi, Dong-Geun;Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.8 no.1
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    • pp.1-9
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    • 2006
  • Regardless of the recent observed warmer winters in Korea, more freeze injuries and associated economic losses are reported in fruit industry than ever before. Existing freeze-frost forecasting systems employ only daily minimum temperature for judging the potential damage on dormant flowering buds but cannot accommodate potential biological responses such as short-term acclimation of plants to severe weather episodes as well as annual variation in climate. We introduce 'dormancy depth', in addition to daily minimum temperature, as a complementary criterion for judging the potential damage of freezing temperatures on dormant flowering buds of grape vines. Dormancy depth can be estimated by a phonology model driven by daily maximum and minimum temperature and is expected to make a reasonable proxy for physiological tolerance of buds to low temperature. Dormancy depth at a selected site was estimated for a climatological normal year by this model, and we found a close similarity in time course change pattern between the estimated dormancy depth and the known cold tolerance of fruit trees. Inter-annual and spatial variation in dormancy depth were identified by this method, showing the feasibility of using dormancy depth as a proxy indicator for tolerance to low temperature during the winter season. The model was applied to 10 vineyards which were recently damaged by a cold spell, and a temperature-dormancy depth-freeze injury relationship was formulated into an exponential-saturation model which can be used for judging freeze risk under a given set of temperature and dormancy depth. Based on this model and the expected lowest temperature with a 10-year recurrence interval, a freeze risk probability map was produced for Hwaseong County, Korea. The results seemed to explain why the vineyards in the warmer part of Hwaseong County have been hit by more freeBe damage than those in the cooler part of the county. A dormancy depth-minimum temperature dual engine freeze warning system was designed for vineyards in major production counties in Korea by combining the site-specific dormancy depth and minimum temperature forecasts with the freeze risk model. In this system, daily accumulation of thermal time since last fall leads to the dormancy state (depth) for today. The regional minimum temperature forecast for tomorrow by the Korea Meteorological Administration is converted to the site specific forecast at a 30m resolution. These data are input to the freeze risk model and the percent damage probability is calculated for each grid cell and mapped for the entire county. Similar approaches may be used to develop freeze warning systems for other deciduous fruit trees.

Sentiment Analysis of Movie Review Using Integrated CNN-LSTM Mode (CNN-LSTM 조합모델을 이용한 영화리뷰 감성분석)

  • Park, Ho-yeon;Kim, Kyoung-jae
    • Journal of Intelligence and Information Systems
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    • v.25 no.4
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    • pp.141-154
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    • 2019
  • Rapid growth of internet technology and social media is progressing. Data mining technology has evolved to enable unstructured document representations in a variety of applications. Sentiment analysis is an important technology that can distinguish poor or high-quality content through text data of products, and it has proliferated during text mining. Sentiment analysis mainly analyzes people's opinions in text data by assigning predefined data categories as positive and negative. This has been studied in various directions in terms of accuracy from simple rule-based to dictionary-based approaches using predefined labels. In fact, sentiment analysis is one of the most active researches in natural language processing and is widely studied in text mining. When real online reviews aren't available for others, it's not only easy to openly collect information, but it also affects your business. In marketing, real-world information from customers is gathered on websites, not surveys. Depending on whether the website's posts are positive or negative, the customer response is reflected in the sales and tries to identify the information. However, many reviews on a website are not always good, and difficult to identify. The earlier studies in this research area used the reviews data of the Amazon.com shopping mal, but the research data used in the recent studies uses the data for stock market trends, blogs, news articles, weather forecasts, IMDB, and facebook etc. However, the lack of accuracy is recognized because sentiment calculations are changed according to the subject, paragraph, sentiment lexicon direction, and sentence strength. This study aims to classify the polarity analysis of sentiment analysis into positive and negative categories and increase the prediction accuracy of the polarity analysis using the pretrained IMDB review data set. First, the text classification algorithm related to sentiment analysis adopts the popular machine learning algorithms such as NB (naive bayes), SVM (support vector machines), XGboost, RF (random forests), and Gradient Boost as comparative models. Second, deep learning has demonstrated discriminative features that can extract complex features of data. Representative algorithms are CNN (convolution neural networks), RNN (recurrent neural networks), LSTM (long-short term memory). CNN can be used similarly to BoW when processing a sentence in vector format, but does not consider sequential data attributes. RNN can handle well in order because it takes into account the time information of the data, but there is a long-term dependency on memory. To solve the problem of long-term dependence, LSTM is used. For the comparison, CNN and LSTM were chosen as simple deep learning models. In addition to classical machine learning algorithms, CNN, LSTM, and the integrated models were analyzed. Although there are many parameters for the algorithms, we examined the relationship between numerical value and precision to find the optimal combination. And, we tried to figure out how the models work well for sentiment analysis and how these models work. This study proposes integrated CNN and LSTM algorithms to extract the positive and negative features of text analysis. The reasons for mixing these two algorithms are as follows. CNN can extract features for the classification automatically by applying convolution layer and massively parallel processing. LSTM is not capable of highly parallel processing. Like faucets, the LSTM has input, output, and forget gates that can be moved and controlled at a desired time. These gates have the advantage of placing memory blocks on hidden nodes. The memory block of the LSTM may not store all the data, but it can solve the CNN's long-term dependency problem. Furthermore, when LSTM is used in CNN's pooling layer, it has an end-to-end structure, so that spatial and temporal features can be designed simultaneously. In combination with CNN-LSTM, 90.33% accuracy was measured. This is slower than CNN, but faster than LSTM. The presented model was more accurate than other models. In addition, each word embedding layer can be improved when training the kernel step by step. CNN-LSTM can improve the weakness of each model, and there is an advantage of improving the learning by layer using the end-to-end structure of LSTM. Based on these reasons, this study tries to enhance the classification accuracy of movie reviews using the integrated CNN-LSTM model.

A Study on the Differences in Breeding Call of Cicadas in Urban and Forest Areas (도시와 산림지역 매미과 번식울음 차이 연구)

  • Kim, Yoon-Jae;Ki, Kyong-Seok
    • Korean Journal of Environment and Ecology
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    • v.32 no.6
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    • pp.698-708
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    • 2018
  • The purpose of this study was to investigate differences in the breeding call characteristics of cicada species found in urban and forest areas in the central region of Korea by examining the interspecific effects and environmental factors affecting the breeding calls and breeding call patterns. The selected research sites were Gyungnam Apartment in Bangbae-dong, Seoul for the urban area and Chiak Mountain National Park in Wonju for the forest area. The research method for both sites was to record cicada breeding calls for 24 hours with a recorder installed at the site and analyze the results. Data from the Korea Meteorological Administration were used for environmental factors. The research period was from June 19, 2017 to September 30, 2017. As a result of the study, there were differences in the emergence of species between the two research sites: while Platypleura kaempferi, Hyalessa fuscata, Meimuna opalifera, Graptopsaltria nigrofuscata, and Suisha coreana were observed at both sites, Cryptotympana atrata was observed in the urban area and Leptosemia takanonis in the forest area only. The emergence periods of cicadas at the two sites were also different. The activities of P. kaempferi and L. takanonis were noticeable in the forest area. In the urban area, however, L. takanonis was not observed and the duration of activity of P. kaempferi was short. In the urban area, C. atrata appeared and sang for a long period; H. fuscata, M. opalifera, and G. nigrofuscata appeared earlier than in the forest area. S. coreana appeared earlier in the forest area than in the urban area. According to the daily call cycle analysis, even cospecific cicada showed a wide variation in their daily cycle depending on the region and the interspecific effects between different cicadas, and the environmental differences between the urban and forest areas affected the calls of cicadas. The results of correlation analysis between each cicada breeding calls and environmental factors of each site showed positive correlation with average temperature of most cicadas except P. kaempferi and C. atrata. The same species of each site showed positive correlations with more diverse weather factors such as solar irradiance. Logistic regression analysis showed that cicadas with overlapping calling times had significant effects on each other's breeding calls. C. atrata, which appeared only in the urban area, had a positive effect on the calling frequency of H. fuscata, M. opalifera, and G. nigrofuscata, which called in the same period. Additionally, L. takanonis, which appeared only in the forest area, and P. kaempferi had a positive effect on each other, and M. opalifera had a positive effect on the calling frequency of H. fuscata and G. nigrofuscata in the forest area. For the environmental factors, the calling frequency of cicadas was affected by the average temperatures of the urban and forest areas, and cicadas that appeared in the forest area were also affected by the amount of solar radiation. According to the results of statistical analysis, urban cicadas with similar activity periods are influenced by species, especially with respect to urban dominant species, C. atrata. Forest cicadas were influenced by species, mainly M. opalifera, which is a forest dominant species. The results of the meteorological impact analysis were similar to those of the correlation analysis, and were influenced mainly by the temperature, and the influence of the insolation was more increased in the forests.

A Study on the Seawater Filtration Characteristics of Single and Dual-filter Layer Well by Field Test (현장실증시험에 의한 단일 및 이중필터층 우물의 해수 여과 특성 연구)

  • Song, Jae-Yong;Lee, Sang-Moo;Kang, Byeong-Cheon;Lee, Geun-Chun;Jeong, Gyo-Cheol
    • The Journal of Engineering Geology
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    • v.29 no.1
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    • pp.51-68
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    • 2019
  • This study performs to evaluate adaptability of seashore filtering type seawater-intake which adapts dua1 filter well alternative for direct seawater-intake. This study varies filter condition of seashore free surface aquifer which is composed of sand layer then installs real size dual filter well and single filter well to evaluate water permeability and proper pumping amount according to filter condition. According to result of step aquifer test, it is analysed that 110.3% synergy effect of water permeability coefficient is happened compare to single filter since dual filter well has better improvement. dual filter has higher water permeability coefficient compare to same pumping amount, this means dual filter has more improved water permeability than single filter. According to analysis result of continuous aquifer test, it is evaluated that dual filter well (SD1200) has higher water permeability than single filter well (SS800) by analysis of water permeability coefficient using monitoring well and gauging well, it is also analysed dual filter has 110.7% synergy effect of water permeability coefficient. As a evaluation result of pumping amount according to analysis of water level dropping rate, it is analysed that dual filter well increased 122.8% pumping amount compare to single filter well when water level dropping is 2.0 m. As a result of calculating proper pumping amount using water level dropping rate, it is analysed that dual filter well shows 136.0% higher pumping amount compare to single filter well. It is evaluated that proper pumping amount has 122.8~160% improvement compare to single filter, pumping amount improvement rate is 139.6% compare to averaged single filter. In other words, about 40% water intake efficiency can be improved by just installation of dual filter compare to normal well. Proper pumping amount of dual filter well using inflection point is 2843.3 L/min and it is evaluated that daily seawater intake amount is about $4,100m^3/day$ (${\fallingdotseq}4094.3m^3/day$) in one hole of dual filter well. Since it is possible to intake plenty of water in one hole, higher adaptability is anticipated. In case of intaking seawater using dual filter well, no worries regarding damages on facilities caused by natural disaster such as severe weather or typhoon, improvement of pollution is anticipated due to seashore sand layer acts like filter. Therefore, It can be alternative of environmental issue for existing seawater intake technique, can save maintenance expenses related to installation fee or damages and has excellent adaptability in economic aspect. The result of this study will be utilized as a basic data of site demonstration test for adaptation of riverside filtered water of upcoming dual filter well and this study is also anticipated to present standard of well design and construction related to riverside filter and seashore filter technique.

Effects of Planting and Harvest Times on the Forage Yield and Quality of Spring and Summer Oats in Mountainous Areas of Southern Korea (남부산간지에서 봄과 여름 조사료 귀리의 파종과 수확 시기에 따른 조사료 품질과 생산성 변화)

  • Shin, Seonghyu;Lee, Hyunjung;Ku, Jahwan;Park, Myungryeong;Rha, Kyungyoon;Kim, Byeongju
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.66 no.2
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    • pp.155-170
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    • 2021
  • Oats (Avena sativa L.) represent a good forage crop for cultivation in regions with short growing periods and/or cool weather, such as the mountainous areas of southern Korea. In this study, using the Korean elite summer oat varieties 'High speed' and 'Dark horse', we aimed to determine the optimal time to plant and harvest forage oats seeded in spring and summer in a mountainous area. Seeds were planted three times from late February and early August at 9- or 10-days intervals, respectively, and plants were harvested three times from late May to October at 10-day intervals. The experiment was carried out in an upland field (Jangsu-gun Jeonbuk) in 2015 and 2016. We investigated the changes in forage yield (FY) and quality [crude protein (CP) and total digestible nutrient (TDN) contents] based on the time of planting and harvest. Neither the forage quality nor yield of either spring and summer oats was significantly influenced by the time of planting. The CP of spring oats harvested three times at 10-day intervals from late May was 12.0%, 8.2%, and 6.5%, thereby indicating a reduction with a delay in the time of harvest. In summer oats, CP ranged from 8.4% to 8.7%, although unlike CP in spring oats, was not significantly influenced by the time of harvest. For both forage types, harvest time had no significant effect on TDN. The FY of spring oats harvested in late May and early and mid-June was 10.2, 18.7, and 19.5 ton ha-1, respectively, with that of oats harvested on the latter two dates being significantly increased by 83% and 91%, respectively, compared with that in late May. Similarly, the FY of spring oats harvested in late October and early and mid-November was 7.1, 12.5, and 12.1 ton ha-1, respectively, with that of oats harvested on the latter two dates being significantly increased by 75% and 71%, respectively, compared with that in late October. Taking into consideration forage yield and quality (not less than 8% CP), it would be profitable to plant spring oats in the mountainous areas of southern Korea until March 15 and harvest around June 10, whereas summer oats could be beneficially planted until August 25 and harvested from early November.

A Study on the System of Aircraft Investigation (항공기(航空機) 사고조사제도(事故調査制度)에 관한 연구(硏究))

  • Kim, Doo-Hwan
    • The Korean Journal of Air & Space Law and Policy
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    • v.9
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    • pp.85-143
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    • 1997
  • The main purpose of the investigation of an accident caused by aircraft is to be prevented the sudden and casual accidents caused by wilful misconduct and fault from pilots, air traffic controllers, hijack, trouble of engine and machinery of aircraft, turbulence during the bad weather, collision between birds and aircraft, near miss flight by aircrafts etc. It is not the purpose of this activity to apportion blame or liability for offender of aircraft accidents. Accidents to aircraft, especially those involving the general public and their property, are a matter of great concern to the aviation community. The system of international regulation exists to improve safety and minimize, as far as possible, the risk of accidents but when they do occur there is a web of systems and procedures to investigate and respond to them. I would like to trace the general line of regulation from an international source in the Chicago Convention of 1944. Article 26 of the Convention lays down the basic principle for the investigation of the aircraft accident. Where there has been an accident to an aircraft of a contracting state which occurs in the territory of another contracting state and which involves death or serious injury or indicates serious technical defect in the aircraft or air navigation facilities, the state in which the accident occurs must institute an inquiry into the circumstances of the accident. That inquiry will be in accordance, in so far as its law permits, with the procedure which may be recommended from time to time by the International Civil Aviation Organization ICAO). There are very general provisions but they state two essential principles: first, in certain circumstances there must be an investigation, and second, who is to be responsible for undertaking that investigation. The latter is an important point to establish otherwise there could be at least two states claiming jurisdiction on the inquiry. The Chicago Convention also provides that the state where the aircraft is registered is to be given the opportunity to appoint observers to be present at the inquiry and the state holding the inquiry must communicate the report and findings in the matter to that other state. It is worth noting that the Chicago Convention (Article 25) also makes provision for assisting aircraft in distress. Each contracting state undertakes to provide such measures of assistance to aircraft in distress in its territory as it may find practicable and to permit (subject to control by its own authorities) the owner of the aircraft or authorities of the state in which the aircraft is registered, to provide such measures of assistance as may be necessitated by circumstances. Significantly, the undertaking can only be given by contracting state but the duty to provide assistance is not limited to aircraft registered in another contracting state, but presumably any aircraft in distress in the territory of the contracting state. Finally, the Convention envisages further regulations (normally to be produced under the auspices of ICAO). In this case the Convention provides that each contracting state, when undertaking a search for missing aircraft, will collaborate in co-ordinated measures which may be recommended from time to time pursuant to the Convention. Since 1944 further international regulations relating to safety and investigation of accidents have been made, both pursuant to Chicago Convention and, in particular, through the vehicle of the ICAO which has, for example, set up an accident and reporting system. By requiring the reporting of certain accidents and incidents it is building up an information service for the benefit of member states. However, Chicago Convention provides that each contracting state undertakes collaborate in securing the highest practicable degree of uniformity in regulations, standards, procedures and organization in relation to aircraft, personnel, airways and auxiliary services in all matters in which such uniformity will facilitate and improve air navigation. To this end, ICAO is to adopt and amend from time to time, as may be necessary, international standards and recommended practices and procedures dealing with, among other things, aircraft in distress and investigation of accidents. Standards and Recommended Practices for Aircraft Accident Injuries were first adopted by the ICAO Council on 11 April 1951 pursuant to Article 37 of the Chicago Convention on International Civil Aviation and were designated as Annex 13 to the Convention. The Standards Recommended Practices were based on Recommendations of the Accident Investigation Division at its first Session in February 1946 which were further developed at the Second Session of the Division in February 1947. The 2nd Edition (1966), 3rd Edition, (1973), 4th Edition (1976), 5th Edition (1979), 6th Edition (1981), 7th Edition (1988), 8th Edition (1992) of the Annex 13 (Aircraft Accident and Incident Investigation) of the Chicago Convention was amended eight times by the ICAO Council since 1966. Annex 13 sets out in detail the international standards and recommended practices to be adopted by contracting states in dealing with a serious accident to an aircraft of a contracting state occurring in the territory of another contracting state, known as the state of occurrence. It provides, principally, that the state in which the aircraft is registered is to be given the opportunity to appoint an accredited representative to be present at the inquiry conducted by the state in which the serious aircraft accident occurs. Article 26 of the Chicago Convention does not indicate what the accredited representative is to do but Annex 13 amplifies his rights and duties. In particular, the accredited representative participates in the inquiry by visiting the scene of the accident, examining the wreckage, questioning witnesses, having full access to all relevant evidence, receiving copies of all pertinent documents and making submissions in respect of the various elements of the inquiry. The main shortcomings of the present system for aircraft accident investigation are that some contracting sates are not applying Annex 13 within its express terms, although they are contracting states. Further, and much more important in practice, there are many countries which apply the letter of Annex 13 in such a way as to sterilise its spirit. This appears to be due to a number of causes often found in combination. Firstly, the requirements of the local law and of the local procedures are interpreted and applied so as preclude a more efficient investigation under Annex 13 in favour of a legalistic and sterile interpretation of its terms. Sometimes this results from a distrust of the motives of persons and bodies wishing to participate or from commercial or related to matters of liability and bodies. These may be political, commercial or related to matters of liability and insurance. Secondly, there is said to be a conscious desire to conduct the investigation in some contracting states in such a way as to absolve from any possibility of blame the authorities or nationals, whether manufacturers, operators or air traffic controllers, of the country in which the inquiry is held. The EEC has also had an input into accidents and investigations. In particular, a directive was issued in December 1980 encouraging the uniformity of standards within the EEC by means of joint co-operation of accident investigation. The sharing of and assisting with technical facilities and information was considered an important means of achieving these goals. It has since been proposed that a European accident investigation committee should be set up by the EEC (Council Directive 80/1266 of 1 December 1980). After I would like to introduce the summary of the legislation examples and system for aircraft accidents investigation of the United States, the United Kingdom, Canada, Germany, The Netherlands, Sweden, Swiss, New Zealand and Japan, and I am going to mention the present system, regulations and aviation act for the aircraft accident investigation in Korea. Furthermore I would like to point out the shortcomings of the present system and regulations and aviation act for the aircraft accident investigation and then I will suggest my personal opinion on the new and dramatic innovation on the system for aircraft accident investigation in Korea. I propose that it is necessary and desirable for us to make a new legislation or to revise the existing aviation act in order to establish the standing and independent Committee of Aircraft Accident Investigation under the Korean Government.

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