• Title/Summary/Keyword: 소수기

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Original Landscape of MuGi-YeonDang and Yuhoejeong Pavilion Area in Chirwon through (<하환정도(何換亭圖)>를 통해 본 칠원 무기연당(舞沂蓮塘)과 유회정(有懷亭) 일곽의 원형경관)

  • Rho, Jae-Hyun;Son, Hee-Kyung;Park, Tae-Hee
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.4
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    • pp.1-13
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    • 2017
  • This thesis aims to research the original landscape of an area in Chirwon by comparing and interpreting the current and the former landscape of the time around 1860, in which was created. Inside the painting, MuGi-YeonDang(舞沂蓮塘), its nearby garden facilities and landscape are described. The conclusions of the research are as follows. Around the inner garden(內園) called Gukdam(菊潭), core spaces of Mugi-YeonDang were Hahwanjeong(何換亭) and Pungyongnu(風浴樓). After 1971, Chunghyosa(忠孝祠), Yeongjeonggak(影幀閣) which was built as inheritance of Giyangseowon (沂陽書院), and other buildings were added. On the opposite of Hahwanjeong, there is a designed pond inside Gukdam, in which three pieces of bizarre stones and colorful flower plants and trees reside. In the middle of the pond, there is an center island(中島), constructed with Bonghwangseok(鳳凰石) and Napduseok(衲頭石). Two different kinds of trees are settled on top of the stones, and one of them is identified as a maple. In the external scenery(外境), Jakdaesan Mountain and Cheonjusan Mountain are located at the upper part of Mugi-Yeondang, and Bibo Forest(裨補林), which does not exist anymore, was located at the lower part of it. A notable achievement in own research was to discover the Ju family's graveyard(朱氏墓群) consisted of more than 10 murals at the lower part of Mt. Jakdaesan in the outer space and the remains of 'Byeoreop(別業) Yuhoejeong(有懷亭)' at the nearby Sanjeong-ri(山亭里) area, which was the Ju family's gravesite(Seonsan, 先山). The discovered remains showed the presence of a square pond(方塘) and an island in the center of it(中島) in the form of Seokgasan(an artificial mountain made with stones), a stone monument called Mangchudae(望楸臺), etc. The Seokgasan was consisted of processed natural stones, and layers of the stones were piled up for it. On the side of the layered stones, 'Gyeongam(敬嵒)' and 'Sesim(洗心)' are engraved. Especially, Gyeongja(letter Gyeong, 敬字) is a copy of the Gyeongja Rock(敬字岩) of Sosu-Seowon(紹修書院), which is a symbolic garden language mutually used in the signboards of Pungyongnu and Musansa(武山祠), a place built to enshrine Ju, Sebung(周世鵬). Through the written names of the building found in , it can be assumed that the name of the square pond with Seokgasan was Taehwaji or Jeongwudang, and the name of the Seokgasan was Sogeumgang(小金剛) or Sobangjang(小方丈). The names correspond to the names of the Seokgasan of Gukdam, which was Yangsimdae(養心臺) and Bongnaesan(蓬萊山). By means of the corresponding names, it can be inferred that the relations between the spaces were intended. was originally created as 'a manor painting(莊園圖)', led by the 15th generation of the Ju family who moved into Chirwon-ri, Haman. The painting describes not only the back garden but also the external scenery, thus it provides important evidences for understanding Mugi-YeonDang and its nearby landscape, and is helpful to its maintenance and restoration.

Spatiotemporal and Longitudinal Variability of Hydro-meteorology, Basic Water Quality and Dominant Algal Assemblages in the Eight Weir Pools of Regulated River(Nakdong) (낙동강 8개 보에서 기상수문·기초수질 및 우점조류의 시공간 종적 변동성)

  • Shin, Jae-Ki;Park, Yongeun
    • Korean Journal of Ecology and Environment
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    • v.51 no.4
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    • pp.268-286
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    • 2018
  • The eutrophication and algal blooms by harmful cyanobacteria (CyanoHAs) and freshwater redtide (FRT) that severely experiencing in typical regulated weir system of the Nakdong River are one of the most rapidly expanding water quality problems in Korea and worldwide. To compare with the factors of rainfall, hydrology, and dominant algae, this study explored spatiotemporal variability of the major water environmental factors by weekly intervals in eight weir pools of the Nakdong River from January 2013 to July 2017. There was a distinct difference in rainfall distribution between upstream and downstream regions. Outflow discharge using small-scale hydropower generation, overflow and fish-ways accounted for 37.4%, 60.1% and 2.5%, respectively. Excluding the flood season, the outflow was mainly due to the hydropower release through year-round. These have been associated with the drawdown of water level, water exchange rate, and the significant impact on change of dominant algae. The mean concentration (maximum value) of chlorophyll-a was $17.6mg\;m^{-3}$ ($98.2mg\;m^{-3}$) in the SAJ~GAJ and $29.6mg\;m^{-3}$ ($193.6mg\;m^{-3}$) in the DAS~HAA weir pools reaches, respectively. It has increased significantly in the downstream part where the influence of treated wastewater effluents (TWEs) is high. Indeed, very high values (>50 or $>100mg\;m^{-3}$) of chlorophyll-a concentration were observed at low flow rates and water levels. Algal assemblages that caused the blooms of CyanoHAs and FRT were the cyanobacteria Microcystis and the diatom Stephanodiscus populations, respectively. In conclusion, appropriate hydrological management practices in terms of each weir pool may need to be developed.

History of Plant Protection Science since 1900 in Korea (한국(韓國)에 있어서의 식물보호(植物保護) 연구사(硏究史) -1900년대(年代)를 중심(中心)으로-)

  • Park, Jong-Seong
    • Korean Journal of Agricultural Science
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    • v.6 no.1
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    • pp.69-95
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    • 1979
  • The study was conducted to search developmental process of plant protection science from review of forty-three hundreds literatures presented since 1900 in Korea and to forecast future statues of the science to be done. About 80 percent of literatures related to plant protection science such as plant pathology, applied entomology, weed science and agricultural pharmacology were collected from publications of agricultural and forestry reseach organizations attached to Office of Rural Development and Office of Forestry. The rest of literatures were mainly collected from Korean Journal of Plant Protection Society and small number of literatures were also collected from publications of the other journals of crop science and thesis collection of agricultural colleges. In Korea, research organizations of plant protection science are divided into two main groups such as exclusive agricultural research organizations and agricultural colleges. It is pointed out that the former contributions to plant protection science are very great compared to those of the latter since 1900. From periodical consideration of developmental process of the science since 1900, the history or the science are divided into three eras such as introduction and sprout of modern plant protection science during the first forty years, distress of the science during the following twenty years including the Second World War and the Korean War and rapid growth of the science after 1961. In spite of long time distress of the science during the Second World War and the Korean War, the researches on plant protection science in post-war have been done twice as many as pre-war. From consideration of the subject plants in researches of plant protection, it is shown that a great many researches on protection of rice plant have been done and occupy 37 percent of plant protection researches since 1900. And also researches on protection of fruit-trees and cash-crops are not so many as those of rice plant but have been done in noticeable numbers. In fact, researches on protection of fruit-trees and cashcrops were the most important subjects of plant protection researches in pre-war while those of rice plant were the most important subjects after 1930, particulary in post-war. From consideration of contents of plant protection researches, it is said that more fundamental researches than applied ones such as practical control methods of diseases, insect pests and weeds were done in pre-war while more applied researches than fundamental ones were done in post-war, Among applied researches, those of chemical control were the most important subjects. Researches on disease and insect-pest resistance have been done in both pre-war and post-war while researches on forecasting of disease and insect-pest and race of plant pathogens have been done in post-war. And also researches on weed control mainly have been done after 1960. Researches on agricultural chemicals for control of diseases, insect pests and weeds still belong to a new field which must be expected in future, and there is nothing to notice with the exception of practical application of agricultural chemicals introduced from foreign countries. Some of important researches on diseases and insect pests were discussed in relation to developmental process of plant protection science in Korea since 1900. In future, researches on plant protection will be develop to the direction supporting importance of integrated control for plant protection. Therefore, it is pointed out that security of highly educated and trained scientists with enlargement of reseach fields of plant protection science are necessary and role of agricultural colleges for future development of the science must be emphasized.

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Review of Family Planning / Health Integration Efforts and Evaluation Results in Korea (가족계획과 보건사업의 통합시도 및 평가결과)

  • Bang, Sook
    • Korea journal of population studies
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    • v.10 no.2
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    • pp.58-81
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    • 1987
  • The purpose of this study is to examine major factors that affect patterns of living arrangements of older Korean noncitizens in the United States using the 1990 8% Public Use Microdata Sample(PUMS). In order to do so, I analyzed the effects of four factors including acculturation(English proficiency and Age at migration), economic circumstances(Personal Income and Supplemental Security Income: SSI receipt), health status(Mobility and Personal care limitation), and the ethnic community. The results show that acculturation and economic circumstances play an important role in determining the patterns of living arrangements among older Korean aliens, whereas the health status and the ethnic community do not show consistent effects. Regardless of marital status, the impact of age at migration is positively associated with solitary living of older Korean noncitizens, though, the effect of English proficiency show the opposite direction in accordance with marital status. That is, among nonmarried elders, those who cannot speak English are more likely to live alone. The case is reverse for married elders. The impact of economic feasibility is also positively associated with independent living arrangements. Those who receive SSI are much more likely to live apart from family, and elders whose annual personal income between $5,001 and $10,000 have the greatest propensity of solitary living-a large proportion of their income source is SSI. Individuals who receive SSI are also qualified to collect Medicaid, food stamps, rent subsidies, and other welfare benefits. In a sense, the economic feasibility provided by welfare benefits is the key determinant of independent living of older Korean noncitizens. Therefore, the recent welfare reform which denies legal aliens welfare benefits such as SSI and food stamps will severly affect the present living arrangements of older Korean aliens, and give economic burden to their family member The findings also show that there are significant differences within the elderly Korean Americans in terms of demographics, income, fertility, health status, and patterns of living arrangements by U.S. citizenship status. In particular, after controlling for age at migration as a proxy for acculturation, there is a statistically significant variation in living arrangements between elderly Korean noncitizens and naturalized citizens. For both theoretical and methodological reasons, future research on minority aging needs to investigate the concept of U.S. citizenship status for its impact on patterns of living arrangements among the minority elderly.

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The Heat Transfer Performance of a Heat Pipe for Medium-temperature Solar Thermal Storage System (중온 태양열 축열조용 히트파이프의 열이송 성능)

  • Park, Min Kyu;Lee, Jung Ryun;Boo, Joon Hong
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.69-69
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    • 2011
  • 태양열 발전 플랜트에 사용되는 중고온 범위의 축열조에 고체-액체간 상변화를 수행하는 용융염을 축열물질로 사용하면 액체상 또는 고체상만으로 된 열저장 매체에 비해 축열조의 규모를 축소함과 동시에 축열온도의 균일성 향상에 기여할 수 있다. 중온인 $250{\sim}400^{\circ}C$ 범위에서 이용 가능한 용융염으로는 질산칼륨($KNO_3$), 질산리튬($LiNO_3$)등이 있다. 그러나 이러한 용융염의 가장 큰 단점은 열전도율이 매우 낮다는 것이며, 이로 인해 요구되는 열전달률을 성취하기 위해서는 많은 열접촉면적이 필요하다는 것이다. 이러한 단점을 극복하는 방법을 도입하지 않고서는 축열시스템의 소규화를 성취하는데 큰 효과를 가져올 수 없다. 한편 열수송 성능이 탁월한 히트파이프를 사용하면 열원 및 열침과 축열물질 사이의 열전달 효율을 증가시켜 시스템의 성능 향상과 동시에 소규모화에 기여할 수 있다. 중온 범위 히트파이프의 작동유체로서 다우섬-A(Dowtherm-A)는 $150^{\circ}C$이상 $400^{\circ}C$까지의 범위에서 소수에 불과한 선택적 대안 중 하나이다. 따라서 본 연구에서는 용융염을 사용하는 중온 태양열축열조에 적용 가능한 다우섬-A 히트파이프의 성능을 파악하여 기술적 자료를 제시하고자 하였다. 열원으로는 고온 고압의 과열증기, 그리고 열침으로는 중온의 포화증기를 고려하였다. 용융염 축열조를 수직으로 관통하는 히트파이프는 하단부에서 열원 증기와 열교환 가능하며, 중앙부에서 축열물질과 열교환하고, 상단부에서는 중온 증기와 접촉할 수 있도록 배치하였다. 축열모드에서는 히트파이프의 하단부가 증발부로 작동하고, 중앙부가 응축부로 작동하여 용융염으로 열을 방출하면 용융염의 온도가 상승하고 용융점에 도달하면 액상으로의 상변화가 진행되면서 축열이 활성화된다. 축열모드에서 히트파이프의 상단부는 단열부로 작동한다. 방열과정에서는 히트파이프의 하단부가 단열된 상태이고, 중앙부는 용융염으로부터 열을 받아 증발부로 작동하며, 상단부는 중온 증기로 열을 방출하므로 응축부로 작동한다. 즉, 축열시스템의 작동모드에 따라 하나의 히트파이프에서 증발부, 응축부, 단열부의 위치가 변하게 된다. 특히, 히트파이프의 중앙 부분이 응축부에서 증발부로 전환될 때에도 작동이 보장되려면 내부 작동유체의 연속적인 재순환이 가능해야 하므로, 일반 히트파이프에서와는 달리 초기 작동액체의 충전량을 증발부 전체의 체적보다 더 많이 과충전해야 한다. 이러한 히트파이프의 성능 파악을 위한 실험에서 고려한 변수들은 열부하, 작동액체의 충전률, 작동온도 등이며, 열수송 성능의 지표로서는 유효열전도율과 열저항을 이용하였다. 중온범위에서 적정한 작동온도를 성취하기 위해 실험에서는 전압 조절기로 열부하를 조절하는 동시에 항온조로 응축부의 냉각수 입구 온도를 제어하였다. 하나의 히트파이프에 대해서 최대 1 kW까지의 열부하에서 냉각수 입구 온도를 $40^{\circ}C$에서 $80^{\circ}C$ 범위로 변화시키면 히트파이프 작동온도를 약 $250^{\circ}C$ 내외로 조절 가능하였다. 히트파이프 작동액체 충전률은 윅구조물의 공극 체적을 기준으로 372%에서 420%까지 변화 시켰다. 실험 결과를 토대로 열저항과 유효 열전도율을 각각 입력 열유속, 작동온도, 작동액체 충전률 등의 함수로 제시했다. 동일한 냉각수 온도에서는 충전률이 높을수록 히트파이프의 작동온도가 감소하였다. 열저항 값의 범위는 최소 $0.12^{\circ}C/W$에서 최대 $0.15^{\circ}C/W$까지로 나타났으며 유효 열전도율의 값은 최소 $7,703W/m{\cdot}K$에서 최대 $8,890W/m{\cdot}K$까지 변화했다. 최소 열저항은 충전률 420%인 경우에 나타났는데 이때의 작동온도는 약 $262^{\circ}C$이었다. 히트파이프의 작동한계로서 드라이아웃(dry-out)은 충전률 372%의 경우에 열부하 950 W에서 발생하였으나, 그 이상의 충전률에서는 열부하 1060 W까지 작동한계 발생이 관찰되지 않았다. 실험 결과 본 연구에서의 히트파이프는 중온 태양열 축열조에 적용되어 개당 약 1 kW의 열부하를 이송하면서 축열물질 및 축방열 대상 유동매체와 열교환을 하는데 사용하는데 충분할 것이라 판단된다.

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Chemical and Spectroscopic Characterization of Soil Humic and Fulvic Acids and Sorption Coefficient of Phenanthrene: A Correlation Study (토양 휴믹물질의 화학적.분광학적 특성에 따른 페난트린 흡착상수와의 상관성 규명에 대한 연구)

  • Lee, Doo-Hee;Lee, Seung-Sik;Shin, Hyun-Sang
    • Journal of Korean Society of Environmental Engineers
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    • v.30 no.11
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    • pp.1067-1074
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    • 2008
  • In this study, the organic carbon normalized-sorption coefficients (Koc) for the binding affinity of phenanthrene (PHE) to 16 different soil humic and fulvic acids of various origins were determined by fluorescence quenching. The humic and fulvic acids used in this study were isolated from 6 different domestic soils including Mt. Hanla soil, IHSS standard soil and peat as well as Aldrich humic acid and characterized by elemental composition, ultraviolet absorption at 254 nm, composition of main structural fragments determined by CPMAS $^{13}$C NMR. The Koc values($\times$10$^4$, L/kg C) for each of HA and FA samples were in the range of 1.48$\sim$8.65 and higher in HA compared to that of FA(3.13$\sim$8.65 vs 1.48$\sim$2.48) in the experimental condition([PHE]/[HS] = 0.02$\sim$0.2(mg/L)/(mg-OC/L), pH 6). The correlation study between the structural descriptors of humic and fulvic acids and log Koc values of phenanthrene, show that the magnitude of Koc values positively correlated with the UV$_{254}$ absorptivity([ABS]$_{254}$) and two $^{13}$C NMR descriptors (C$_{Ar-H,C}$, $\sum$C$_{Ar}$/$\sum$C$_{Alk}$), while negatively correlated with the independent descriptors of the(N+O)/C atomic ratios and $^{13}$C NMR descriptors (I$_{C-O}$/I$_{C-H,C}$). These results confirmed that the binding affinity for the hydrophobic organic compound, phenanthrene are significantly influenced by the polarity and aromaticity of soil humc and fulvic acids.

Developmental Changes in Histology and Histochemistry of Epididymal Ducts in Korean Native Goats II. Histochemical changes in epididymal ducts (한국재래산양 정소상체관의 발육에 따른 조직 및 조직화학적 변화 II. 정소상체관의 조직화학적 변화)

  • 김성호;김창근;정영채;이재홍;이방환
    • Korean Journal of Animal Reproduction
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    • v.11 no.3
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    • pp.196-205
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    • 1987
  • This study was conducted in order to obtain the informatin of the histochemical changes in each of 6 segments of the epididymal ducts in 32 Korean native male goats. The male goats were examined, dividing into 7 groups, at 4 잔 intervlas from 8 to 32 wks of age. The reuslts obtained were as follows: 1. PAS reaction showed positive on the basal and upper part beyond the nucleus of the peithelium of effernt ductules throughout all the classes of age. It was also positive on the free border and basal and upper part beyond the nucleus of the caput, on the free border andbasal parts of the corpus, and on the basal part of the cauda of the epididymal epithelium. 2. Acid phosphatase reaction was negative on the every part of epididymal epithelium at the age of 8 weeks, however, with the aging it became strangly positive on the areas between the free border and the nucleus, and moderately positive on the basal part of epithelium of the caput and corpus. In the free border adn basal part of the cauda, it was slightly positive. alkaline phosphatase reactin was negative on the every part of epididymal epithelium until 12 weeks of age. From 16 weeks, free border of epididymal epithelium becaqme slightly positive, and from 20 weeks, the reaction became stronger on the basal part but weekend on the free border with the aging. 3. In the sudan black B staining, many blue black granules between the free border and the nucleus, some granules on the basal part, and a few granules on the cytoplasm around the nucleus of the epididymal epithelium were observed from 8 weeks of age as early, and the granules were increased in number with the aging. 4. In Azan staining, reddish violet granules below the nucleus and blue granules on the upper part beyond the nucleus in some cells of epithelia of efferent ductules were noted at 12th and 16th week, and after 24th week, the granules were decreased with the aging. Golgi apparatus were clearly observable on the upper part beyond the nucleus of all parts of epididymal epithelium from 8th week, and also number of intracytoplasmic vacuoles(smaller ones on the upper part and larger ones on the basal part beyond the nucleus) and fine granules were increased with the aging. 5. In the toluidin blue staining, reddish purple granules on the basal part of the epithelium in all the parts of epididymal ducts, particularly brilliant in the cauda, were observed from 8th week as early. 6. In the Cowdry staining, numerous mitochondria, according to aging, were observed between the free border of epithelium and the upper part beyond the nucleus particularly in the catus and corpus of the epididymal ducts.

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Future Development Strategies for KODISA Journals : Overview of 2017 and Strategic Plans for the Future (KODISA 학술지 성장전략: 2017 개관 및 미래 성장개요)

  • Hwang, Hee-Joong;Shin, Dong-Jin;Lee, Jung-Wan;Kim, Dong-Ho;Lee, Jong-Ho;Kim, Byung-Goo;Kim, Tae-Joong;Lee, Yong-Ki;Suh, Eung-Kyo;Kang, Min-Soo;Seo, Won-Jae;Kim, Jong-Jin;Zhang, Fan;Su, Shuai;Youn, Myoung-Kil
    • Journal of Distribution Science
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    • v.16 no.5
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    • pp.83-90
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    • 2018
  • Purpose - Journals of Korea Distribution Science Association (KODISA) made great efforts in responding to the constant shifts in academic paradigms and in producing synergetic effects among KODISA journals to achieve the goal of maintaining their status in the world's reputable scholarly journals. The aim of this study is to analyze the current practice and performance of KODISA journals and develop strategies that will continuously meet and respond to the changes and success in the future. Research design, data, and methodology - This is a case study, an analytical approach, which focuses on analyzing current and previous strategies, practices, and performances of the four major journals of KODISA and the association. The organizational structure, including election and terms of KODISA officers, new membership, and members of editorial board, is discussed and analyzed. The citation, submission, publication, and rejection rates of all four journals are examined, and the progress, including the status of indexing of each journal, is discussed. Results - The analysis indicates that KODISA has significantly invested its resources into improving its journals and attracting new members. The analysis also shows the strategy of the organizational structure, which includes election and terms of officers and editorial board members that implemented over the years, was successful. Both Journal of Distribution Science (JDS) and Journal of Finance, Economics, and Business (JAFEB) are indexed in SCOPUS, with East Asian Journal of Business Management (EAJBM) in the final stage of the SCOPUS indexing evaluation, and International Journal of Industrial Distribution and Business (IJIDB) will complete and submit their indexing evaluation materials to SCOPUS this summer. Conclusions - The success and progress of KODISA and its journals clearly support the need for continuous development, analysis, revision, and implementation of strategies. Based on the analysis, conducting the annual performance reviews of the association and its journals and planning and strategizing based on the reviews since 2011 have greatly contributed to the overall success. In terms of meeting the short term strategy, KODISA has to continue developing relationships with relevant and appropriate scholarly/academic associations to expand the scope of its business, establishing independence of each journal and its respective procedures and practices and improving the quality of the journals and their publications through KODISA's international conferences.

Chemical Reactions in Surfactant Solutions (Ⅳ) : Micellar Rate Effect on Reactions of Hydroxide and o-Iodosobenzoate Ions with Organic Phosphinates (계면활성제 용액속에서의 화학반응 (제 4 보) : $OH^-$ 및 o-Iodosobenzoate 이온에 의한 유기 포스피네이트의 탈인산화 반응에 미치는 CTAX 미셀의 영향)

  • Hong, Yeong Seok;Kim, Hyeon Muk
    • Journal of the Korean Chemical Society
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    • v.38 no.10
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    • pp.753-762
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    • 1994
  • Dephosphorylation of diphenyl- or isopropylphenyl-4-nitrophenylphosphinate (DPNPIN or IPNPIN) mediated by $OH^-$ or o-iodosobenzoate ion ($IB^-$) are relatively slow in aqueous solution. The reactions in CTAX micellar solutions are, however, very accelerated, because CTAX micelles can accommodate both reactants in their Stern layer in which they can easily react, while hydrophilic $OH^-$(or $IB^-$) and hydrophobic phosphinates are not mixed in water. Even though the concentrations (> $10^{-3}$ M) of $OH^-$(or $IB^-$) in CTAX solutions are much larger amounts than those ($6{\times}10^{-6}$ M) of phosphinates, the rate constants of the dephosphorylations are largely influenced by change of the concentration of the ions, which means that the reactions are not followed by the pseudo first order kinetics. In comparison to effect of the counter ions of CTAX in the reactions, CTACl is more effective on the dephosphorylation of DPNPIN (or IPNPIN) than CTABr due to easier expelling of $Cl^-$ ion by $OH^-$(or $IB^-$) ion from the micelle, because of easier solvation $Cl^-$ ion by water molecules. The reactivity of IPNPIN with $OH^-$(or $IB^-$) is lower than that of DPNPIN. The reason seems that the 'bulky' isopropyl group of IPNPIN hinders the attack of the nucleophiles. The mechanism of reaction of IPNPIN with IB- ion concluded as 'nucleophilic' instead of 'general basic' by a trapping experiment and a measured kinetic isotope effect.

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The Removal of Organics and Nitrogen with Step Feed Ratio Change into the Anoxic and Anaerobic reactor in Advanced Sewage Treatment process Using Nonsurface-modified and Surface-modified Media Biofilm (비개질/개질 생물막을 이용한 오수고도처리공정에서 혐기조와 무산소조의 원수 분배율에 따른 유기물 및 질소 제거)

  • Seon, Yong-Ho
    • KSBB Journal
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    • v.20 no.4
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    • pp.253-259
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    • 2005
  • This study was accomplished using attached $A^2/O$ process that contains nonsurface-modified and surface-modified polyethylene media inside the Anaerobic/Anoxic, Oxic tank, respectively. We could make the hydrophobic polyethylene media have hydrophilic characteristics by radiating ion beam on the surface of the media. The objectives of this study is to investigate the removal efficiencies of the organics and nitrogen when the step feed ratio of raw wastewater into anaerobic and anoxic tank is changed. In this case, we assumed that the denitrification rate can be improved because the nitrifiers in anoxic tank can perform denitrification using RBDCOD instead of artificial carbon sources (for example, methanol, etc.). The wastewater injection rate into anaerobic/anoxic tank was set up by the ratio of 10 : 0, 9 : 1, 8 : 2, 6 : 4, and the results of BOD removal efficiency showed similar trends with $93.3\%,\;92.6\%,\;92.4\%\;and\;91.6\%$, respectively. But the BOD removal efficiency (utilization of the organics) in the anoxic tank was in the order of 9 : 1 $(84.8\%)$, 10 : 0 $(77.0\%)$, 8 : 2 $(75.3\%)$, and 6 : 4 $(61.1\%)$. The T-N removal efficiency was most high when the ratio is 9 : 1 $(67.4\%)$, and other conditions, 10 : 0, 8 : 2, 6 : 4, showed $61.3(\%),\;60.7\%,\;55.5\%$, respectively; the ratio 6 : 4 was found to be lowest T-N removal efficiency, lower than the ratio 9 : 1 by $12\%$. Though the nitrification rate of the ratio 10 : 0, 9 : 1, and 8 : 2 showed similar levels, the ratio 6 : 4 showed considerable inhibition of nitrification, ammonia was the great portion of the effluent T-N. The advantages of this process is that this process is cost-saving, and non-toxic methods than injecting the artificial carbon source.