• Microbiology and Biotechnology Letters
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• v.33 no.3
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• pp.169-177
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• 2005

This study focuses on investigating roles of microorganisms in decontamination of reed rhizosphere in Sunchon Bay, Korea, which is considered one of the marsh and mud environment severely affected by human activities such as agriculture and fisheries. In general, the bay is known to play the role of the buffering zone to reduce the sudden impact or change by environmental stresses. In our initial efforts to elucidate the microbial functions in decontamination process in reed rhizosphere, pure bacteria capable of degrading aromatic hydrocarbons were isolated from reed (Phragmites communis) rhizosphere of Sunchon bay by enrichment culture using either benzene, toluene, ethylbenzene, or xylene (BTEX) as a sole source of carbon and energy. Measurement of the rates of BTEX degradation and cell growth during the incubation in BTEX media under several temperature conditions demonstrated maximized degradation of BTEX at $37^{\circ}C$ in both strains. Both strains were also resistant to all the heavy metals and antibiotics tested in this study, as well as they grew well at $42^{\circ}C$. Identification of the isolates based on 16S rRNA gene sequences, and a variety of phenotypic and morphologic properties revealed that the two strains capable of BTEX catabolism were among Microbacterium sp., and Rhodococcus sp. with over $95{\%}$ confidence, designated Microbacterium sp. EMB-1 and Rhodococcus sp. EMB-2, respectively This result suggested that in the rhizosphere of reed, one of major salt marsh plants they might play an important roles in decontamination process of reed rhizosphere contaminated with petroleum such as BTEX.

• Journal of Radiation Protection and Research
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• v.36 no.4
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• pp.223-229
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• 2011

Ba is the most useful element to get the $Ba(Ra)SO_4$ precipitate. However, when the high concentrations of ions such as sulfate, calcium are existed in the leachate of phosphogypsum stack, it is difficult to get the $Ba(Ra)SO_4$ precipitate. Since this reason, the developed method for the Ba coprecipitate using EDTA was performed to determine the $^{226}Ra$ concentration in the high sulfate sample. The average concentration of $^{226}Ra$ in a leachate of phosphogypsum using this method was 0.102 $Bq{\cdot}kg^{-1}$ and the minimal detectable activity is 3.4 $mBq{\cdot}kg^{-1}$. The $mBq{\cdot}kg^{-1}$ method was 0.102 $Bq{\cdot}kg^{-1}$ and the minimal detectable activity is 3.4 $mBq{\cdot}kg^{-1}$. The $^{226}Ra$ stock solution and the CRM (Certified Reference Material) were analyzed to verify this method. In analyzed $^{226}Ra$ stock solution, bias with added concentration was approximately 1% and the correlation curve between $^{226}Ra$ concentration in simulated standard sample and measured $^{226}Ra$ concentration showed good agreement with a correlation coefficient ($R^2$) of 0.99. In analyzed CRM, maximum bias with reference value was 5.8% (k=1) and the analytical results were in good agreement with the reference value.

• The Journal of Korean Medicine
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• v.20 no.1 s.37
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• pp.52-59
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• 1999

연구목적 : 뇌졸중환자에 기능회복도의 측정을 위해 가장 신뢰도가 높은 MBI에 대해서 순수하게 뇌졸중환자의 운동기능평가만을 위해 고안된 MAS의 상관성을 각 기간별로 분석하여 MAS의 운동기능평가척도로서의 객관성에 대해 연구한다. 또 한편으로 경과시간에 따른 운동기능 회복도의 차이를 전체그룹과 사상그룹에서 평가한다. 연구방법 : 1998년 1월부터 1998년 6월까지 6개월에 걸쳐 상지대학교 한의과대학 부속한방병원 내과에 입원하여 뇌졸중으로 진단된 환자 중 의식과 언어상태가 명료한 32명을 대상으로 하였다. 입원직후 사상의학과에 의뢰하여 QSCCII 시스템에 의하여 체질진단을 받은 후 본원 운동기능평가실에서 입원직후, 입원 후 2주와 4주 등 3회에 걸쳐 Modified Barthel Index(MBI)와 Motor Assessment Scale(MAS)을 시행하였다. 각 환자에 대한 검사는 2명의 한방순환기내과 전문의와 전공의에 의해 환자에 대한 사전 정보 없이 이루어졌다. 연구결과 : 통계처리는 상관분석을 위해서는 Pearson correlation coefficient, 사상체질에 있어서 각 경과시간에 따른 점수변화는 Repeated ANOVA, 일반적특성 분석에는 Descriptive analysis가 사용되었고, 프로그램은 SPSS/PC+ 7.5 version을 사용하였다. 1. 뇌졸중 환자의 사상의학적인 분포는 태음인이 56.3%로 가장 많았고, 소양인이 28.1%, 소음인이 12.5%, 태양인이 3.1%이었으며, 연령별로는 50대가 32.6%로 가장 많았으며, 평균연령은 60.9세였다. 2. 경과시간에 따른 사상체질간의 MBI, MAS 평균점수변화는 MBI, MAS 모두 반복측정 분산분석 결과 입원당시와 2주 후, 입원당시와 4주 후에서 모두 P<0.001의 범위에서 통계학적으로 유의하게 증가하였고, 경과시간과 사상체질간의 교호작용은 없었다. 3. MBI, MAS 모두 각 항목과 기능별 분류군에서도 경과시간에 따른 평균점수의 변화는 P<0.001 범위에서 통계학적으로 유의하게 증가하여 한방치료의 효과가 있음을 보여주었다. 4. MBI와 MAS의 경과시간별 Pearson 상관성 분석결과 입원당시의 MBI와 입원당시의 MAS에서, 2주 후의 MBI와 입원당시, 2주 후, 4주 후의 MAS에서, 4주 후의 MBI와 입원당시, 2주, 4주 후의 MAS에서 모두 높은 상관성을 보여, 두 평가방법 간에는 상관성이 높다고 본다.

• Membrane Journal
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• v.15 no.4
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• pp.297-309
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• 2005

As a number of potential endocrine disrupting compounds (EDCs) are released into the environment, recently growing attention has been drawn to them. Therefore sensitive and reliable analytical methods are essential to monitor those compounds. In this study, complementary CC-MS and LC-MS were employed to analyze the endocrine disrupters, and the results of two methods were compared for di(2-ethylhexyl)phthalate (DEHP), benzylbutylphthalate (BBP), pentachlorophenol (PCP), and 4,4'-Isopropylidenediphenol (Bisphenol-A, or BPA). The results indicate that it was possible to lower the detection limits of EDCs by LC-MS. Also, LC-MS enabled to identify the EDCs as almost intact molecules. Furthermore, this study presented a nanofiltration membrane (MWCO 250) and a ultrafiltration membrane (MWCO 1,000) filtration system as methods far removing EDCs from drinking water containing $\gamma$-BHC, p,p'-DDE, BBP, p,p'-DDT, DEHP, PCP, and BPA. Cross-flow type nanofiltrations showed $100\%$ removal of EDCs, and the result implies that MWCO 250 nanofilter was sufficient for treatment of EDCs. The ratio of permeate flux to mass transfer coefficient of nanofiltration, high flux ultrafiltration, and low flux ultrafiltration with ultrapure water were 0.67, 3.4, and 0.44, respectively. It was found that nanofiltration and low flux ultrafiltration were operated at a diffusion dominant condition, and the high flux ultrafiltration was operated at a convection dominant condition. Furthermore, a diffusion dominant process attained reasonable rejection of EDCs. The removal in the ultrafiltration was depending on the molecular weight of an EDC, and the filtration was governed by diffusion-dominant hydrodynamic conditions.

• Korean Chemical Engineering Research
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• v.51 no.3
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• pp.358-363
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• 2013

Lithium-ammonia (Li-$NH_3$) solutions are possible to be successfully made under the vacuum condition but there still remains a problem of undergoing stable and reliable decomposition in vacuum for high-efficiency thermoelectric power generation. This paper describes a new method for improving the thermoelectric conversion efficiency of Li-$NH_3$ solutions in vacuum. The proposed method uses a 'U'-shaped Pyrex vacuum tube for the preparation and decomposition of pure fluid Li-$NH_3$ solutions. The tube is shaped so that a gas passageway ('U') connecting both legs of the 'U' helps to balance pressure inside both ends of the tube (due to $NH_3$ gasification) during decomposition on the hot side. Thermoelectric experimental results show that solution reaction in the 'U'-shaped tube proceeds more stably and efficiently than in the 'U'-shaped tube, and consequently, thermoelectric conversion efficiency is improved. It is also proved that the proposed method can provide a reversible reaction, which can rotate between synthesis and decomposition in the tube, for deriving the long-time, high-efficiency thermoelectric power.

• International Area Studies Review
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• v.20 no.1
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• pp.105-125
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• 2016

The expansionary monetary policy was practiced after 2001 in Japan to treat the deflation spiral, and reduced only the nominal interest rates and domestic household demand. One of the most serious factors for this failure was the change of private sector's expectancy. This paper has studied the effect of Japanese monetary policy in 21c., with empirical research based on a renewed macroeconomic model and the VAR. The empirical analysis shows that the effect of monetary policy on the national income during 2001.01-2015.03 is weaker than that of 1985.01-1994.04. Money volume has a diminutive effect on the growth of GDP within a short term after 2001. The change in the expectations of the private sectors might have been the cause of ineffectiveness of the expansive monetary policy. Economic agents learned from the past Japanese financial crisis that an expansive monetary policy increased the inflation rate and caused the 'bubbles to burst' afterwards. The VAR analysis says that the effectiveness of monetary policy on the economic depression declined over the past 20 years and the expansion of money volume has no influence on exchange rate and net export. This means that the expansive monetary policy lost its effect on net export and national income steadily. Monetary policy makers have to recognize this fact, and to consider another anti-cycle political instrument, i.e. the fiscal policy with government debt.

• Journal of Korea Entertainment Industry Association
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• v.14 no.2
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• pp.51-62
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• 2020

The study was conducted to verify the causality of the ability of high school and college dance majors to influence the successful goal orientation and how the change in goal affects the sense of dance performance self-confidence. In this regard, 172 dance majors were collected to collect data on their belief in dance ability, the direction of mastery goal of approach and avoidance, and the measure of confidence in dance performance, and the results of their studies were derived through correlation and structural equation analysis and path analysis. The analysis results showed reasonable factor structure and reliability based on the preceding study of feasibility analysis results between variables. Thus, the structural equation for the study variables confirmed that the theoretical hypothesis was suitable, and the path of each variable was verified through the path analysis. The analysis showed that the increased belief that ability can be improved by effort has been found to improve the effort and consequently the confidence in dancing. Also, the fixed belief that ability is not changing in a fixed sense has been found to affect the avoidance goal and reduce confidence. It can be interpreted that the more one believes that one can change one's ability by effort, the more one strengthens one's actions to achieve one's goal, thereby improving one's dance confidence. Therefore, it is deemed necessary for subsequent studies to explore whether the paths of these models differ by their major or dance careers, and to apply variables that can measure the success or failure of actual performances to enhance the explanatory power of these research variables.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.1
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• pp.40-46
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• 2013

The isotope ratios of $^{13}C/^{12}C$ and $^{18}O/^{16}O$ for a sample in a mass spectrometer are measured relative to those of a pure $CO_2$ reference gas (i.e., laboratory working standard). Thus, the calibration of a laboratory working standard gas to the international isotope scales (Pee Dee Belemnite (PDB) for ${\delta}^{13}C$ and Vienna Standard Mean Ocean Water (V-SMOW) for ${\delta}^{18}O$) is essential for comparisons between data sets obtained by other groups on other mass spectrometers. However, one often finds difficulties in getting well-calibrated standard gases, because of their production time and high price. Additional difficulty is that fractionation processes can occur inside the gas cylinder most likely due to pressure drop in long-term use. Therefore, studies on laboratory production of pure $CO_2$ isotope standard gas from stable solid calcium carbonate standard materials, have been performed. For this study, we propose a method to extract pure $CO_2$ gas without isotope fractionation from a solid calcium carbonate material. The method is similar to that suggested by Coplen et al., (1983), but is better optimized particularly to make a large amount of pure $CO_2$ gas from calcium carbonate material. The $CaCO_3$ releases $CO_2$ in reaction with 100% pure phosphoric acid at $25^{\circ}C$ in a custom designed, evacuated reaction vessel. Here we introduce optimal procedure, reaction conditions, and samples/reactants size for calcium carbonate-phosphoric acid reaction and also provide the details for extracting, purifying and collecting $CO_2$ gas out of the reaction vessel. The measurements for ${\delta}^{18}O$ and ${\delta}^{13}C$ of $CO_2$ were performed at Seoul National University using a stable isotope ratio mass spectrometer (VG Isotech, SIRA Series II) operated in dual-inlet mode. The entire analysis precisions for ${\delta}^{18}O$ and ${\delta}^{13}C$ were evaluated based on the standard deviations of multiple measurements on 15 separate samples of purified $CO_2$. The pure $CO_2$ samples were taken from 100-mg aliquots of a solid calcium carbonate (Solenhofen-ori $CaCO_3$) during 8-day experimental period. The multiple measurements yielded the $1{\sigma}$ precisions of ${\pm}0.01$‰ for ${\delta}^{13}C$ and ${\pm}0.05$‰ for ${\delta}^{18}O$, comparable to the internal instrumental precisions of SIRA. Therefore, we conclude the method proposed in this study can serve as a way to produce an accurate secondary and/or laboratory $CO_2$ standard gas. We hope this study helps resolve difficulties in placing a laboratory working standard onto the international isotope scales and does make accurate comparisons with other data sets from other groups.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.7 no.1
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• pp.1-7
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• 2009

This study has been focused on determining the chemical composition of $^{14}C$ - in terms of both organic and inorganic $^{14}C$ contents - in reactor coolant from 3 different PWR's reactor type. The purpose was to evaluate the characteristic of $^{14}C$ that can serve as a basis for reliable estimation of the environmental release at domestic PWR sites. $^{14}C$ is the most important nuclide in the inventory, since it contributes one of the main dose contributors in future release scenarios. The reason for this is its high mobility in the environment, biological availability and long half-life(5730yr). More recent studies - where a more detailed investigation of organic $^{14}C$ species believed to be formed in the coolant under reducing conditions have been made - show that the organic compounds not only are limited to hydrocarbons and CO. Possible organic compounds formed including formaldehyde, formic acid and acetic acid, etc. Under oxidizing conditions shows the oxidized carbon forms, possibly mainly carbon dioxide and bicarbonate forms. Measurements of organic and inorganic $^{14}C$ in various water systems were also performed. The $^{14}C$ inventory in the reactor water was found to be 3.1 GBq/kg in PWR of which less than 10% was in inorganic form. Generally, the $^{14}C$ activity in the water was divided equally between the gas- and water- phase. Even though organic $^{14}C$ compound shows that dominant species during the reactor operation, But during the releasing of $^{14}C$ from the plant stack, chemical forms of $^{14}C$ shows the different composition due to the operation conditions such as temperature, pH, volume control tank venting and shut down chemistry.

• Proceedings of the Korea Society of Poultry Science Conference
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• 1998.04a
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• pp.51-86
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• 1998

$\bigcirc$ 재래닭 생산물의 소비 및 구매형태 등에 대한 조사에서 종합적인 결론은 최종 소비자의 응답자는 총 2,250명이었으며 연령, 성별, 직업, 거주지, 주거형태, 가족수, 소득분포등이 비교적 다양하게 분포되어 있다. 판매업소의 특성은 지역별, 매장면적, 업주연령, 성별, 경력등에서 매장위치는 약 60%가 농촌이고 관광지 21.3%, 도시 19.0%순이였으며 매장 면적은 10-30평이 66.9%, 경력은 3년이하 27.4%, 3-5년 22.7%, 5-10년 22.2%였다. $\bigcirc$ 재래닭고기의 소비형태에서 육류선호도는 쇠고기, 돼지고기, 닭고기 순이였으며 재래닭고기의 소비형태에서 전체 응답자의 64.4%가 먹어본 경험이 있었다. 주로 섭취시기는 74.5%가 여름철에 식구들과 같이 회식할 때 식사대용이나 부식용으로 섭취하였다. 소비자가 재래닭고기를 좋아하는 이유는 고기가 쫄깃쫄깃하여 씹는맛과 지방이 적으며 단백한 맛 때문에 독특해서 좋아한다고 하였으며, 싫어하는 이유는 너무 질기고 고기의 양이 너무 적다는 의견이 많았다. 선호하는 요리방법은 백숙, 삼계탕이었고 좋아하는 부위는 역시 다리부위였다. 재래닭고기의 섭취량에 대하여는 1회에 2인이 1마리를 먹는다가 36.4%, 3인이 1마리 31.8%로서 68.2%가 2-3인이 1마리를 먹는다고 하였으며, 가족구성원 중에는 가장이 제일 선호하는 것으로 나타났다. $\bigcirc$ 음식점에서 판매되는 요리한 재래닭의 1마리 가격에 대한 의견은 84.5%가 20,000원정도면 부담이 없이 먹겠다고 하였다. $\bigcirc$ 재래닭의 구입행동에서 구입주체는 주부였으며, 구입장소는 농.축협의 슈퍼와 정육점이었고 백화점과 재래닭 사육장에서 직접구입도 하고 있었다. 구입 동기는 가족들이 좋아하고 영양가를 생각한다가 62%였으며 구입정보는 주위사람의 권유로 구입하고 있었다. $\bigcirc$ 구입할 때 중점적으로 살펴보는 사항은 신선도와 순수재래종 여부, 위생상태였다. 한편 소비자가 언제나 구입할 수 없다는 의견이 85.2%나 되어 원활한 공급과 시장조성이 아직 정착되지 않고 있었다. $\bigcirc$ 현재 유통되고 있는 재래종닭은 소비자 대부분이 잡종으로 인식하고 있었으며, 재래종과 일반육계와의 구별은 깃털색, 피부색, 정강이색등 외관상으로 구별하고 있었다. 체중에 대한 반응은 너무 작다는 의견이었고, 식품으로의 인식도는 비교적 고급식품으로 인식하고 있다. $\bigcirc$ 재래종닭고기의 브랜드화에 대한 견해는 젊고 소득이 높은 계층에서 브랜드화의 필요성을 강조하고 있다. $\bigcirc$ 재래종달걀의 소비형태는 대부분의 소비자가 좋아하였으나 아직 먹어보지 못한 응답자가 많았다. 재래종달걀의 맛에 대해서는 고소하고 독특하여 차별성을 느끼고 있었다. $\bigcirc$ 재래종달걀의 구입장소는 계란판매점(축협.농협), 슈퍼, 백화점, 재래닭 사육 농장등 다양하였으며 포장단위는 10개를 가장 선호하였고, 포장재료는 종이, 플라스틱, 짚의 순으로 좋아하였다. $\bigcirc$ 달걀의 가격은 200원정도를 적정하다고 하였으며, 크기는 (평균 52g)는 가장 적당하다고 인식하고 있으며, 난각색은 대부분의 응답자가 갈색을 선호하였다. $\bigcirc$ 재래종달걀의 구입시 애로사항은 믿을수 없고, 구입장소를 몰라서, 값이 싸다 등이었고, 앞으로 신뢰할 수 있고 위생적인 생산 및 유통체계가 확립될 경우 더 많이 소비하겠다는 의견이었다. $\bigcirc$ 재래닭 판매업소(식당)의 판매형태는 66.7%인 대부분의 업소가 잡종과 개량종 유색닭을 판매하고 있었으며, 1개 업소에서 1일 판매수수는 5-10수의 영세한 판매형태였고, 계절적으로는 여름철에 대부분을 판매하였다. $\bigcirc$ 식당에서 판매하는 재래닭고기의 요리 종류는 주로 백숙이었고, 삼계탕, 닭볶음도 있었으며, 요리된 재래닭 1마리 가격은 20,000원 이상이었으며, 20,000원이하로 판매하는 잡종이 많았다. $\bigcirc$ 재래닭 판매업소에서 재래닭을 구입하는 방법은 재래닭 사육농장에서 1회에 수십마리 구입하여 판매업소의 간이 사육장에서 기르면서 판매하는 업소가 49.6%, 도계된 재래닭을 구입하여 판매하는 업소 26.9%, 직접 재래닭을 사육하면서도 도계하여 판매하는 업소가 21.7%였다. 판매업소에서의 재래닭 사육기간은 90일 이상이었으며 대부분의 업주는 야산에서 방사한 것을 좋게 생각하고 있었다.