• 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.

• Journal of Korean Medical classics
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• v.13 no.2 s.17
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• pp.44-56
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• 2000

장개빈(張介賓)(1563-1640, 호시경악(號是景岳))시명말의학가이계승김원대의학전통적인물(是明末醫學家而繼承金元代醫學傳統的人物). 타재(他在) 류경도익(類經圖翼), 의역의(醫易義) 주장'의역동원'이논증의학여역학지회통성(主張'醫易同源'而論證醫學與易學之會通性). 타이성리학이론내연구의학(他以性理學理論來硏究醫學). 인이피칭위'유의'(因而被稱爲'儒醫'). 타광범지연구유가급제자백가지후(他廣範地硏究儒家及諸子百家之後), 이(以) 황제내경(黃帝內經) 여(與) 난경 위주(難經 爲主). 종합의가학설(綜合醫家學說). 타이(他以) '양상부족음본무여'지관념내설명인체내음양상태('陽常不足陰本無餘'之觀念來說明人體內陰陽狀態) 이반박주진형지자음론(而反駁朱震亨之滋陰論). 인이주장'부양억음'급'태극시명문'적학설(因而主張'扶陽抑陰'及'太極是命門'的學說). 타재(他在) 의역의(醫易義) 이부양억음내해설병리(以扶陽抑陰來解說病理). 관어태극-명문적론의야수성리학태극개념적영향(關於太極-命門的論議也受性理學太極槪念的影響). 단시(但是), 소위(所謂) '조원찬화'('調元贊化') '기사회생'적의학목적시속어도교양생론('起死回生'的醫學目的是屬於道敎養生論). 관어차점(關於此點), 연피칭위유의적성리학의가야병부예외(連被稱爲儒醫的性理學醫家也竝不例外). 일반인위 황제내경 시재전국 한대초기형성적(一般認爲 黃帝內經 是在戰國 漢代初期形成的). 야인위기의학체계반영저황로사상여음양오행론(也認爲其醫學體系反映著黃老思想與陰陽五行論). 장개빈수재성리학적립장내주장자기적이론(張介賓雖在性理學的立場來主張自己的理論). 단시대폭지접수도가급도교립장(但是大幅地接受道家及道敎立場). 타재(他在) 류경도익(類經圖翼), 태극도론(太極圖論), 이태극성위만물생명적근원(以太極成爲萬物生命的根源). 동시언급도도가여역위(同時言及到道家與易緯). 재장개빈(在張介賓), 태극시상통어도가발생론적개념(太極是相通於道家發生論的槪念). 야상통어태극적개념(也相通於太極的槪念). 재(在) 유경(類經), 섭생(攝生) 내간(來看). 타제요로장이외(他除了老莊以外). 우인용송대이후내단사상가강백단 이도순등적주장(又引用宋代以後內丹思想家强伯端 李道純等的主張), 인이전개자기적이론(因而展開自己的理論). 필자시위(筆者視爲), 장개빈재의학적양생방면상접수료이'성명쌍수'위기적송대이후내단사상(張介賓在醫學的養生方面上接受了以'性命雙修'爲基的宋代以後內丹思想). 병차타이연단적관점내이해부양억음(竝且他以煉丹的觀點來理解扶陽抑陰). 신위유의적장개빈능구장유도량자회통위일조의학체계적의거재어역학.(身爲儒醫的張介賓能구將儒道兩者會通爲一條醫學體系的依據在於易學). 장개빈재천인상응관념지하(張介賓在天人相應觀念之下), 용이음양변화지기구내변증천인관계(用以陰陽變化之機構來辨證天人關係). 재타적이론(在他的理論), 천지시속어 역(天地是屬於 易), 인시속어 의(人是屬於 醫), 단시양자귀위동일양적일리(但是兩者歸爲同一樣的一理). 재'원취제물(在'遠取諸物), 근취제신'적관점내강(近取諸身'的觀點來講), 타장'근취제신'적도리취어의학(他將'近取諸身'的道理取於醫學). 환유'원취제물'적도리취어역학(還有'遠取諸物'的道理取於易學), 인이모구귀납성일개원리(因而謀求歸納成一個原理). 타장자연현상적원리내재어인지생명(他將自然現象的原理內在於人之生命), 종여차정체적각도내간(從如此整體的角度來看). 가이설의학시상통어역학적(可以說醫學是相通於易學的). 역학대인여자연간적탐구(易學對人與自然間的探求), 비교측중어이론성(比較側重於理論性). 반이의학이역학이론위자(反而醫學以易學理論爲資). 관어자연여인지생명진일보지진행교구체성적연구(關於自然與人之生命進一步地進行較具體性的硏究). 총지(總之), 장개빈통과태극음양론(張介賓通過太極陰陽論), 부분유 도이참재'생명'적립장(不分儒 道而站在'生命'的立場), 광범지접납유도양가(廣範地接納儒道兩家). 유차(由此) 아문가이여도장개빈의서적가치병부한어의학가치(我們可以如道張介賓醫書的價値竝不限於醫學價値). 장개빈의서제시유 도량가가이회통어"생명사상"적철학상가능성(張介賓醫書提示儒 道兩家可以會通於"生命思想"的哲學上可能性).

• Korean Journal of Construction Engineering and Management
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• v.19 no.6
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• pp.103-114
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• 2018

Public-Private-Partnership(PPP) is becoming a popular form of projects in construction industry worldwide. Normally, the management team of PPP project consists of various experts from different disciplines such as construction engineer, bank financier, contract manager, investors, etc. The diversity of team members causes difficulties in managing the team efficiently and furthermore for the smooth execution of the project itself. One of the solutions to this issue might be the application of citizenship behavior by the team members. This study conducts an empirical investigation of the effect of project citizenship behavior on the project performance. We have collected data by using a questionnaire from those with PPP project experiences in the domestic construction industry. The results show that project citizenship behavior has full mediating effects between PM's leadership and the project performance. This study has an academic significance in that it is the first attempt to apply the concept and to show the effect of citizenship behavior in project management discipline, particularly in construction industry, in Korea. We also expect that the project management teams for PPP projects would benefit from the findings of this study.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.323-329
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• 2014

Population of fruit flies was monitored by using methyl eugenol trap during 2010-2011 in Yezin, Myanmar. Population numbers were analyzed with meteorological factors including rainfall, temperature, relative humidity and duration of sunshine. Samples of mango, guava, and jujube fruits were collected from orchards. The fruits were kept in containers so that the species of flies infesting the fruit could be identified when the adult insects emerged and to assess damage caused by fruit flies. Regression analyses indicated that populations of fruit flies were observed to be positively correlative with rainfall, minimum temperature and relative humidity, and negatively correlative with the duration of sunshine. Eleven species of fruit flies, Bactrocera arecae, B. carambolae, B. correcta, B. dorsalis, B. kandiensis, B. latilineola, B. malaysiensis, B. neocognata, B. raiensis, B. verbascifoliae, and Carpomya vesuvina, were identified. B. correcta and B. dorsalis were the most abundant and accounted for 29.3% and 28.6% of total emerged adults in the different fruit samples. The highest percentage of fruit damage was observed on guava ($59{\pm}15.4$), followed by mango ($35.5{\pm}12.1$) while the lowest was recorded on jujube ($18.5{\pm}7.9$).

• Economic and Environmental Geology
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• v.48 no.1
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• pp.65-75
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• 2015

The CBM(Coalbed Methane) development technology being developed in mid 1980s is the technology to produce the methane gas absorbed in the coal bed. CBM is easy to be developed and its coal deposit is abundant. Therefore, the CBM industry has a large potential as an energy source as well as to deal with the global regulations for reducing greenhouse gas emission. In order to produce coal, the CBM should first be developed as a preliminary action for mine security. So CBM is advantageous in reducing the global greenhouse gas as well as its advantage not being influenced by the changes in gas market. The ECBM (Enhanced Coalbed Methane) is a new technique producing the methane gas which is substituted and disorbed from coal by injecting $CO_2$ or $N_2$ gas into a coal bed. Especially, $CO_2$-ECMB is a low-carbon, green-growth technology, so can expect to the effect of green gas reduction as well as the improved productivity of methane gas. CBM technology is being developed in about 40 nations including Canada, Australia, China, India, Indonesia and Viet Nam, and the coal output using this technology is continually being increased. The CBM is expected to contribute in changing the energy source paradigm from current coal & petroleum energy to unconventional gas.

• Journal of the Korean Geographical Society
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• v.43 no.4
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• pp.477-494
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• 2008

Stable isotope analyses on lake or wetland sediments are useful to reconstruct paleoclimate. Organic and inorganic carbonates obtained from lake sediment are isotopically analyzed to get oxygen and carbon isotopic ratios. Oxygen isotope ratios can be used to quantitatively and qualitatively reconstruct paleo-temperature or humidity while carbon isotope ratios be used to reveal environmental changes around the lake or human impacts on the area. Peat mosses in peat bogs are nice samples for the carbon isotope analysis, which derives paleo-temperature and paleo-atmospheric $CO_2$ changes. In coastal area, the reconstruction of past sea-level is possible because terrestrial originated organic matter is carbon isotopically different from marine originated organic matter. Also, scientists can do research on Asian Monsoon based on the fact that $\delta^{13}C$ of C3 plants and C4 plants are consistently different each other and that they are distributed differently with respect to salinity. In Korea, paleoenvironmental studies using stable isotopes are not popular yet because of low academic interests on the methodology and difficulties of obtaining proper sediment samples. Interesting results can be produced to answer paleoenvironmental questions of Korea if scientists isotopically analyze sediment cores from a paleo-lake such as Hanon in Jeju island, peat bogs such as Mujechi-Neup and Yong-Neup, and coastal wetlands.

• Korean Journal of Medicinal Crop Science
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• v.9 no.1
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• pp.1-7
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• 2001

This experiment was carried out to investigate the effects of shading treatments and harvesting methods on the growth of Eleutherococcus senticosus, which was known as the medicine of anticancer, anti-stress, hepatic detoxification activity, immunoactivity, and tonic. Light transmission ratio and air temperature were decreased as $40{\sim}64%$,$1.9{\sim}2^{\circ}C$, respectively, in 30% to 70% shading net treatment compared to non-shading. Fifty percentage shading net treatment was effective for the growth and yield of Eleutherococcus senticosus. During summer Eleutherococcus senticosus was growing under shading net treatment compared to non-shading. Tunnel type was more effective for growth than vertical type in shading method. 30cm length included 2 to 3 nodes cutting from soil surface was the most effective for branching stem length, plant height and yield as harvesting methods.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.4
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• pp.284-291
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• 2010

A simulation modeling for predicting the harvesting date with high potato solids consists of development of mathematical models. The mathematical model on potato growth and its development should be obtained by using agricultural elements which analyze relations of solar radiation quantity, temperature, photon quantity, carbon dioxide exchange rate, water stress and loss, relative humidity, light intensity, and wind etc. But more reliable way to predict harvesting date against climatic change employs in vivo energy consumption for growth and induction shape in a slight environmental adaptation. Therefore, to calculate in vivo energy loss, we take a concept of estimate of the amount of basal metabolism in each tuber on the basis of $Wm={\int}^m_tf(x)dt$ and $Tp=\frac{Tm{\cdot}Wm^{Tp}}{Wm^{Tm}}$. In the validation experiments, results of measuring solid accumulation of potato harvested at simulated date agreed fairly well with the actual measured values in each regional field during the growth period of 2005-2009. The calculation method could be used to predict an appropriate harvesting date for a production of high potato solids according to weather conditions.

• Korean Journal of Environmental Agriculture
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• v.2 no.1
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• pp.18-23
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• 1983

Effect of Cd, Pb, and Zn content in soil on their accumulation in rice was studied by analyzing brown rice(93) and soil samples(180) collected from paddy soils near old zinc-mining sites in 1979 and 1980. Ratio of Cd, Pb, and Zn in brown rice to soil decreased with the increase of their contents in soil and found to be linear function of the inversed values of their contents in soil. Contents of Cd, Pb, and Zn in brown rice harvested in 1980 were lower than those in 1979. The significant difference in contents of Pb and Zn between two years might be attributed to weather. Air temperature and duration of sunshine in 1980 were significantly lower than those in 1979.

• Food Science of Animal Resources
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• v.28 no.2
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• pp.222-231
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• 2008

This study was carried out to develop a method for decreasing the heavy metal composition of living stock. Sprague-Dawley (SD) male rats were pre-treated with heavy metals administered i.p. at the limits of regulation according to the feed CODEX in Korea. Herbal medicine remnant was administered p.o. (2, 4 ppm of average feeding amount) for the entire period of study with organic selenium (2 ppm of average feeding amount) before any other treatment. 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) was also administered i.p. in a single dose of 60 mg/kg body weight before animals were sacrificed. The TBARS test with the FOX assay demonstrates a decrease of heavy metals due to these functional materials in vitro. Moreover, this decrease in heavy metals was also demonstrated by in vivo tests based on SD rats hair analysis and organ analysis after 6 weeks. A good linear correlation between hair analysis and organ analysis represented by liver and blood was shown. The present findings suggest that measurement method of heavy metal composition using hair analysis for healthy livestock can be used in place of detection methods carried out by organ and blood analysis, and herbal medicines with organic selenium may be very effective at decreasing heavy metals of feed materials in feed manufacture industry.