• Title/Summary/Keyword: Water Ways

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Compressive Strength Experiment of Lightweight Concrete Using Coarse Aggregate Produced by 3D Printing (3D 프린팅으로 제작한 굵은 골재를 사용한 경량콘크리트의 압축강도 실험)

  • Ahn, Byung-Ju
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.5
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    • pp.54-59
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    • 2020
  • Coarse aggregate is produced in various ways depending on the location and production method. Currently, the construction industry is in need of a stable supply of coarse aggregate and a way to secure standard quality. The purpose of this study is to examine whether the use of coarse aggregate in 3D printing can help solve this problem. ABS filament was selected for use in 3D printing. CATIA was used for the design of the coarse aggregate, and CUBICON Single Plus was used for the production. Six specimens were produced and cured in water for 28 days. Three of them were made with AE agent, and three were made without it. A compressive strength test confirmed that when the AE agent was used, the compressive strength was greater than the lightweight concrete design criterion specified in the concrete standard specification. This suggests that coarse aggregate produced by a 3D printer may be used for lightweight concrete. A mass production system using this method could help to solve the problems facing the construction industry, such as stable supply and demand for coarse aggregate and securing standard quality.

A Study on the Distribution Map Construction of Asbestos Buildings Owned by Seoul Using QGIS (QGIS를 활용한 서울시 소유 석면건축물 분포지도 제작에 관한 연구)

  • Lee, Jin Hyo;Bae, Il Sang;Ha, Kwang Tae;You, Seung Sung;Han, Kyu Mun;Eo, Soo Mi;Jung, Kweon;Lee, Jin Sook;Koo, Ja Yong
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.9
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    • pp.528-533
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    • 2016
  • One of ways for effectively maintaining asbestos buildings is to select asbestos buildings to be removed firstly by manufacturing and analyzing asbestos map of various topics. Thus, in this study we manufactured asbestos map of various topics for the effective management of asbestos buildings owned by Seoul using QGIS (Quantum Geographic Information System). To select asbestos buildings likely to cause asbestos scattering problem and exposure into the air, we comprehensively took into consideration various topics such as asbestos buildings density, asbestos-area ratio, asbestos buildings distribution considering the population, first removal object, risk assessment, elapsed year. As described in this study, using the GIS may be utilized as a method for selecting asbestos buildings to be removed firstly as well as distribution of asbestos buildings. In the future, it is necessary to make assessment criteria considering diversification of property value in GIS such as the characteristics of the living environment around the asbestos buildings. This is expected to be utilized to manage the vulnerable region to asbestos exposure.

Characteristics of Input and Output of Scientific Research (국가별 과학연구 투입과 성과의 특성분석)

  • Park, Hyun-Woo;Kim, Kyung-Ho;Yeo, Woon-Dong
    • Journal of Korea Technology Innovation Society
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    • v.12 no.3
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    • pp.471-498
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    • 2009
  • The ability to judge a country's scientific standing is vital for the governments and businesses that must decide scientific priorities and funding. In this paper, we analyze the output and outcomes from research investment over the recent years, to measure the quality of scientific research on national scales and to set it in an international context. There are many ways to evaluate the quality of scientific research, but few have proved satisfactory. To measure the quantity and quality of science in different nations, we analyzed the numbers of published research papers and their citations. The number of citations per paper is a useful measure of the impact of a nation's research output. Essential at a were acquired from SCI database by Thomson Scientific, which indexes more than 8,000 journals, representing most significant materials in science and engineering. The purpose of this paper is to evaluate and compare the output and outcomes among nations in a variety of viewpoints and criteria. One of the implications in response to the result of analysis is that sustainable economic development in highly competitive world markets requires a direct engagement in the generation of knowledge. Even modest improvement in healthcare, clean water, sanitation, food, and transport need capabilities in engineering, technology, and medicine beyond many countries' reach. Nations exporting natural resources such as gold and oil can import technology and expertise, but only until these resources are exhausted. For them, sustainability should imply investment in alternative agricultural and technological capabilities through improvements in their skills base. A strong science base does not necessarily leat to wealth generation. However, strength in science has additional benefits for individual nations, and for the world as a whole.

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A Study on the Fire Prevention Activities and Suppression Measures of Utility-Pipe Conduit (지하공동구 화재예방활동 및 진압대책에 관한 연구)

  • Lee, Jung-Il
    • Journal of the Korean Society of Hazard Mitigation
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    • v.10 no.4
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    • pp.63-68
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    • 2010
  • Utility-Pipe Conduit is, Housing and city effectively accommodate what they absolutely need power, communications, gas, pipeline, water supply, drainage, energy facilities etc, according to expansion of urban infrastructure are derived, several ways to solve problems in, collection facilities in place are maintained and managed facility. If Utility-Pipe Conduit is damaged, as well as national security, because their impact on society as a whole, by introducing large vulnerability in the fire prevention activities and suppression measures and disaster for our situation by introducing measures, comprehensive analysis of the fire risk, it shall establish fire prevention activities and suppression through analysis of Utility-Pipe Conduit design, institutional issues, the problem of fire protection facilities, fire spread phenomenon etc. Because of Utility-Pipe Conduit is an enclosed place, so incomplete combustion due to lack of oxygen supply that there are problem such dark smoke, carbon monoxide etc, toxic combustion products and heat generation and visual impairment is an issue difficult to enter. As well as fire prevention activities, the fire In light of the particularity of the under ground than above ground fire, so this phenomenon is weak fire fighting that fire to become effective fire fighting tactics, basically it is necessary difficulty softening, non-burn softening and prevent combustion expansion of the cable is installed on the Utility-Pipe Conduit, having to considering the specificity of the response command system and relevant organizations to establish an on-site, Structural identification and other information gathering required to record of Response agencies, keep air conditioning system 24 hours and strengthening Virtual Total Training of Response agen

A Study on the Promotion of Adolescent's Milk Consumption (II) -Relationships of Adolescent's Milk Intake Frequency with Food Attitude, Snacking Frequency, Physical Activity and School Vending Facilities- (청소년의 우유섭취 증진방안 연구(II) -중.고등학생의 식태도, 간식빈도, 신체활동 및 교내판매시설과 우유 섭취 빈도와의 상관관계-)

  • Park, Myeong-Sun;Hong, Geum-Jin;Jo, Yeong-Seon;Lee, Jeong-Won
    • Journal of the Korean Dietetic Association
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    • v.13 no.1
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    • pp.73-83
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    • 2007
  • In order to investigate the ecological factors affecting milk intake frequency of adolescents, the questionnaire survey was conducted with 929 middle and high school students living in Chungnam urban area through October and November 2004. The subjects consumed milk 8.6$\pm$6.7 times per week, other beverages 4.4$\pm$4.1 times per week and drinking water 3.7$\pm$2.1 cups per day. Of the students 77.3% took balanced meals, 72.8% ate regularly and 36.2% ate adequate amount. About 61% had breakfast everyday and nearly a half students snacked once a day. Nutritional knowledge scores about milk was 7.2$\pm$1.7 and milk attitude scores was 28.1$\pm$6.5. The subjects spent daily 1.8$\pm$1.1, 1.9$\pm$1.1, and 1.0$\pm$0.5 hours for computer use, TV watching and exercise, respectively. Milk intake frequencies were positively correlated with excercise, snack frequency, meal balance and regularity, breakfast frequency, food attitude score and milk preference, while showed negative correlationships with TV watching and computer use. Intake frequency of fruit-tasted and chocolate milk showed inverse correlation with nutritional knowledge. Subjects without either school store or vending machine took milk more frequently than those with one or both did. Of the correlated variables, milk preference was the most important influencing factor to milk intake frequency according to the stepwise linear regression analysis, which presented other 5 important influencing factors as food attitude, school vending facilities, excercise, snacking frequency and watching TV. In conclusion, the improvement of milk preference is the most important and effective way to promote milk consumption in adolescents. The favorite ways of drinking milk, nutritional benefit of milk, healthy beverage and good snacking should be taught in nutrition education. Also physical activities should be recommended to students rather than watching TV, computer use and vending facilities selling soft drinks should be limited to be established inside school.

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Germination Continuity and Restoration of Salicornia europaea, Halophyte in West-coast of Korea (서해안 염생식물 퉁퉁마디의 발아지속과 복원)

  • Kim, Ki-Hoon;Kang, Nae-Kyu;Song, Uh-Ram;Lee, Eun-Ju
    • Journal of Environmental Science International
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    • v.21 no.2
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    • pp.181-188
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    • 2012
  • Salicornia europaea (glasswort) is succulent, annual, halophytic plant mainly distributed throughout reclaimed land or salt marsh. It has strong tolerance to salt so that it plays the part of the pioneer species in the first succession. According to domestic and foreign studies, S. europaea contains plenty of minerals and antioxidant in the body. Since people take note of an availableness of this plant as health diet, the natural growth sites are threatened. In addition to development of salt marsh and sea shore, imprudent harvest has a bad effect to S. europaea population maintenance. To seek ways to preserve the population of this plant, we carried out the continuity of seed germination and restoration test. Seokmo Island, Daebu Island, Youngjong Island and Sudokwon landfill in Korea are selected sites for research. Result of germination continuity shows that most S. europaea seeds germinate on March but no more after July. However the germination was occurred after that time in the greenhouse. So we concluded that no germination after July is a matter of environmental condition not the number of remaining seeds. Also germination was seldom occurred in the spot where seeds production was not happened. In result of continuity test of seed germination by soil depth, germination was occurred vigorously only in top soil. From these results, we note that most S. europaea germinate in the early spring, and germination is finished by July. And this rapid germination speed makes the number of seeds in soil seed bank rare. If a large number of S. europaea in some area are harvested after July, the number of this species will dramatically decrease in that area the following year. In Seokmo Island, we carried out reintroduction experiment by sowing S. europaea seeds. On the first year, a small number of S. europaea settled and they produced seeds successfully. On April 2010, the second year, we observed many S. europaea in seed sowing sites. And we found out that plowing is more efficient than treatment sea water for settlement of S. europaea.

An early warning and decision support system to reduce weather and climate risks in agricultural production

  • Nakagawa, Hiroshi;Ohno, Hiroyuki;Yoshida, Hiroe;Fushimi, Erina;Sasaki, Kaori;Maruyama, Atsushi;Nakano, Satoshi
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.303-303
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    • 2017
  • Japanese agriculture has faced to several threats: aging and decrease of farmer population, global competition, and the risk of climate change as well as harsh and variable weather. On the other hands, the number of large scale farms is increasing, because farm lands have been being aggregated to fewer numbers of farms. Cost cutting, development of efficient ways to manage complicatedly scattered farm lands, maintaining yield and quality under variable weather conditions, are required to adapt to changing environments. Information and communications technology (ICT) would contribute to solve such problems and to create innovative technologies. Thus we have been developing an early warning and decision support system to reduce weather and climate risks for rice, wheat and soybean production in Japan. The concept and prototype of the system will be shown. The system consists of a weather data system (Agro-Meteorological Grid Square Data System, AMGSDS), decision support contents where information is automatically created by crop models and delivers information to users via internet. AMGSDS combines JMA's Automated Meteorological Data Acquisition System (AMeDAS) data, numerical weather forecast data and normal values, for all of Japan with about 1km Grid Square throughout years. Our climate-smart system provides information on the prediction of crop phenology, created with weather forecast data and crop phenology models, as an important function. The system also makes recommendations for crop management, such as nitrogen-topdressing, suitable harvest time, water control, pesticide spray. We are also developing methods to perform risk analysis on weather-related damage to crop production. For example, we have developed an algorism to determine the best transplanting date in rice under a given environment, using the results of multi-year simulation, in order to answer the question "when is the best transplanting date to minimize yield loss, to avoid low temperature damage and to avoid high temperature damage?".

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Analysis on the Effectiveness of Environmental-friendly Agriculture Rearing Project (친환경농업 지구조성사업 효과분석에 관한 연구)

  • Hyeon, Byeong-Keun;Son, Yeon-Kyu;Jeong, Sug-Jae;Song, Kwan-Cheol;Kim, Lee-Yeol;Kim, Sun-Kwan;Kwak, Han-Kang
    • Korean Journal of Soil Science and Fertilizer
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    • v.39 no.2
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    • pp.53-58
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    • 2006
  • The Korean Ministry of Agricultural & Forestry(MAF) has designated some model areas and has supported financially to encourage sustainable farming under the environment-friendly agriculture rearing project(EARP) since 1995. This study was conducted to diagnose the project and to find ways to improve the effectiveness of EARP. The 18 areas (823 ha) such as Gyeonggi-Do, Gangwon-Do, Chungcheongbuk-Do, Chungcheongnam-Do, and Jeju-Do of 32 areas under EARP in 2004 were examined. Most of the practices implemented in EARP areas were not practical for sustainable agriculture except some equipments and facilities. It was thought that practical technologies for sustainable agriculture were more essential than equipments and facilities to improve the effectiveness of EARP. And area-specific technologies are needed to decrease environmental pollution. For example, liquefied slurry application and duck-rice farming in paddy fields near a watershed could increase the possibility of water pollution by nutrient outflow. Soil characteristics were important factors that could affect the effect of practices on environment conservation. Woodchip application and subsoil crash were not effective in coarse-textured soils. It was recommended that every practices under EARP should be re-examined in the light of the effects on environment before implementation and be evaluated by experts after completion.

Effects of the Order of Material Addition on the Quality Characteristics of Emulsification Sausage (원부재료의 투입 순서가 유화형 소시지의 품질 특성에 미치는 영향)

  • Jin, Sang-Keun;Kim, Il-Suk;Nam, Young-Wook;Cho, Ju-Hyun;Hur, Sun-Jin;Kang, Suk-Nam
    • Food Science of Animal Resources
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    • v.27 no.2
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    • pp.157-162
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    • 2007
  • Emulsification sausages were prepared in 3 different ways: T1: fat added after ice, T2: fat added before ice, T3: all ingredients added together. Each sample was ground for 4.5 min by a silent cutter at $15^{\circ}C$ and emulsified batters were stuffed into fibrous casing and then cooked for 40 min at $78^{\circ}C$ to determine the effect of the order of ingredient addition on the qualities of emulsion type sausage. The pH of T1 sausage was significantly higher, whereas the pH of T3 was significantly lower compared with the other samples(p<0.05). The shear force was significantly higher in T1 sausage, however the hardness and gumminess were significantly lower in T1 sausage compared with other two types(p<0.05). With regard to sensory evaluation, the relative amounts of flavor can be summarized as T2>T1>T3, and the color was significantly higher in T1 and T2 compared with T3(p<0.05). There was no significant difference among the test sausages with regard to aroma, juiciness, tenderness and overall acceptability(p>0.05). There were no significant differences in free moisture, water holding capacity(WHC), meat color and texture properties such as brittleness, cohesiveness, springiness and chewiness. As a result of this study, the sausage were much for sausage prepared by adding the fat after the ice(T1) than the other sausage samples in which fat was added after ice to make emulsion type sausages.

Effects of Feeding Purple Rice (Oryza sativa L. Var. Glutinosa) on the Quality of Pork and Pork Products

  • Jaturasitha, Sanchai;Ratanapradit, Punnares;Piawong, Witapong;Kreuzer, Michael
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.4
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    • pp.555-563
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    • 2016
  • Purple rice is a strain of glutaneous rice rich in anthocyanins and ${\gamma}$-oryzanol. Both types of compounds are involved in antioxidant and lipid metabolism of mammals. Three experimental diet types were used which consisted approximately by half either of purple rice, white rice or corn. Diets were fed to $3{\times}10$ pigs growing from about 30 to 100 kg. Meat samples were investigated either as raw or cured loin chops or as smoked bacon produced from the belly. Various physicochemical traits were assessed and data were evaluated by analysis of variance. Traits describing water-holding capacity (drip, thaw, and cooking losses) and tenderness (sensory grading, shear force) of the meat were mostly not significantly affected by the diet type. However, purple rice feeding of pigs resulted in lower fat and cholesterol contents of loin and smoked bacon compared to white rice, but not compared to corn feeding except of the fat content of the loin. The shelf life of the raw loin chops was improved by purple rice as well. In detail, the occurrence of thiobarbituric acid reactive substances after 9 days of chilled storage was three to four times higher in the white rice and corn diets than with purple rice. The n-6:n-3 ratio in the raw loin chops was 9:1 with purple rice and clearly higher with 12:1 with the other diets, meat lipids. Level and kind of effect of purple rice found in raw meat was not always recovered in the cured loin chops and the smoked bacon. Still the impression of flavor and color, as well as overall acceptability were best in the smoked bacon from the purple-rice fed pigs, whereas this effect did not occur in the cured loin chops. These findings suggest that purple rice has a certain, useful, bioactivity in pigs concerning meat quality, but some of these effects are of low practical relevance. Further studies have to show ways how transiency and low recovery in meat products of some of the effects can be counteracted.