• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.1
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• pp.223-233
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• 2014

This study empirically analyzes the relationships among the road and traffic experts' personal characteristics, the driving behavior and factors being expected to have an effect on the satisfaction about roundabout operation. The factors are drawn and grouped through the principle component analysis to clarify driving environment satisfaction on roundabout operation. Each group is named as personal attribute, driving behavior attribute, and satisfaction. After the variables are refined by confirmatory factor analysis, satisfaction model is developed with personal attribute and driving behavior attributes as exogenous variables and roundabout driving awareness and emotion attributes as endogenous variables. As a result, driving satisfaction of roundabout operation is directly influenced by delay reduction, safety improvement, capacity increase, sight improvement, severity accident reduction, and bicycle convenience and indirectly gender, age, driving time, and driving experience. Law obeyance, driving concession, traffic sign obeyance, and interposition do not statistically shows significant on satisfaction. As a result of Analytical Hierarchy Process (AHP), the turning radius of geometry and the driving behavior are important elements for roundabout safety.

• The Korean Journal of Zoology
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• v.39 no.3
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• pp.317-324
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• 1996

Osteoclast has been known as a primary responsible cell for the bone resorption. The activation of osteoclast, therefore, may be the key event in the regulation of bone growth and remodeling. Various factors were reported to have influence on the resorbing activity of osteoclast in organ culture. Among those factors, transforming growth factor-$\beta$ (TGF-$\beta$) has been known to have a profound effect on bone metabolism. Since a large amount of TGF-$\beta$ presents in bone tissue, it may be important for the understanding the regulatory mechanism of bone resorption to elucidate the effect of TGF-$\beta$ on the osteoclast. We have reported the dlsaggregated chick embryonic osteoclast culture as an useful assay method for determining the resorption activity of osteoclast. In this culture, we found that TGF-$\beta$ significantly enhaced the osteoclastic bone resorption activity. We also found that the timulatory effect seemed to be an indirect one that is mediated by other cells. As nordihydroguaiaretic acid significantly inhibited the TGF-$\beta$1-induced osteoclastic bone resorption, we suggest that the lipoxygenase derivative of arachidonic acid may participate in the action of TGF-$\beta$ as a paracrine or an autocrine mediator.

• Clinical and Experimental Pediatrics
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• v.52 no.9
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• pp.1005-1014
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• 2009

Purpose:Epilepsy of child may cause high level of psychosocial difficulties for parents including stigmatization and stress and therefore worsen their quality of life (QOL). The purpose of this study was to evaluate the mediating effect of perceived stigma against epilepsy on QOL among parents with epileptic child. Methods:Two hundred and sixty parents of epileptic child recruited from five separated university hospital child neurology clinics specializing in epilepsy completed a demographic questionnaire, a medical questionnaire, a perceived stigma questionnaire and the Ro's Quality of Life Inventory, a popular tool for evaluating QOL of adults in Korea which is composed of 6 domains and 47 questions. Data was analyzed with SPSS 14.0 program using frequency analysis and descriptive analysis and with AMOS 7.0 program using Structural Equation Model (SEM) analysis. Results:The level of parents' QOL was relatively fair. SEM analysis on the quality of life level of parents showed that all variables (especially having religion, the monthly income, employment state, age of child, the leisure time, the perceived stigma level against epilepsy, and seizure frequency) directly affect the quality of life level of parents and that disease-related variables also affect the quality of life level of parents indirectly through the mediating factor (the perceived stigma), where the indirect effect is large with the existence of combined disabilities. The total effect on the quality of life level of parents is large with the existence of combined disabilities, the perceived stigma level, the leisure time, having religion, and the monthly income. Conclusion:The results of this study indicated that many factors including parents' perceived stigma may affect the quality of life of parents with epileptic children directly, and that some disease-related factors may affect indirectly through a mediating factor, the perceived stigma. Multidisciplinary collaboration would be imperative for their welfare.

• Korean Journal of Psychosomatic Medicine
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• v.25 no.2
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• pp.193-199
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• 2017

Objectives : Insomnia may be one of the risk factor for suicidal ideation, but little is known about the mechanism by which sleep disturbances confer risk for suicide. The aim of this study was to investigate examine whether insomnia severity would be associated with resilience and suicidal ideation, and whether resilience would mediate the relationship between insomnia and suicidal ideation. Methods : A total of 432 community-dwelling adults(227 male, 205 female,) completed the self-report questionnaire that covered basic socio-demographic data. To assess the psychological variables, the following instruments were applied: Insomnia Severity Index(ISI), Korean Version of the Connor-Davidson Resilience Scale(K-CD-RISC), Beck Hopelessness Scale(BHOP) and Scale for Suicidal Ideation(SSI-Beck). People with an ISI score of 8 or higher were defined as insomnia. Results : Greater insomnia symptom severity was significantly associated with higher level of suicidal ideation and lower level of resilience, adjusting for hopelessness, age, sex, presence of family members living together, and household income. Additional analysis revealed that disturbance of sleep initiation and disturbance of sleep maintenance were significantly associated with suicidal ideation. Mediation analyses revealed that resilience significantly accounted for the relationship between insomnia symptom severity and suicidal ideation. Conclusions : These findings suggest that the evaluation and control of insomnia and resilience may be needed to reduce the risk of suicide.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.3
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• pp.159-165
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• 2005

The characterization of radiological contamination inside pipes generated during the decommission of a nuclear facility is necessary before pipes can be recycled or disposed. But, existing direct measurements of radioactive contamination level using the survey-meter can not estimate the characteristic of contamination on a local area such as the pipe inside. Moreover, the measurement of surface contamination level using the indirect methods has many problems of an application because of the difficulty of collecting sample and contamination possibility of a worker when collecting sample. In this work, plastic scintillator was simulated by using Monte Carlo simulation method for detection of beta radiation emitted from internal surfaces of small diameter pipe. Simulation results predicted the optimum thickness and geometry of plastic scintillator at which energy absorption for beta radiation was maximized. In addition, the problem of scintillator processing and transferring the detector into the pipe inside was considered when fabricating the plastic detector on the basis of simulation results. The characteristic of detector fabricated was also estimated. As a result, it was confirmed that detector capability was suitable for the measurement of contamination level. Also, the development of a detector for estimating the radiological characteristic of contamination on a local area such as the pipe inside was proven to be feasible.

• Journal of Korean Port Research
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• v.11 no.1
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• pp.85-99
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• 1997

The improvements of berth productivity is closely related to berth/port systems and its relationship extends to the overall pattern of port development/logistics, transport and trade. Since ports in general and berths in specific function as a bridge transferring seaborne cargoes from seaside to landside and vice versa, berth productivity improvements should be considered in terms of the total system in which the cargoes are transported from origin to destination via berths/ports. In that respect, the objective of this study is to improve berth productivity which is a vital factor in the strategic planning in port development and operation and logistics. According to a literature survey on the subject, the contents of the studies have been limited to either a macro-perspective or a micro-perspective which is only a partial solution to the problem. Hence, this limitation requires an integrated approach to find and ultimate solution, which should be considered not separately, but as a whole. The contents and scope of this study cover the improvements of berth productivity in conjunction with strategic planning in port development. efficient operation and logistics from two different viewpoints, macro- and micro-perspective. After that, a combination of these two perspectives is applied to the integrated approach due to lacking a comprehensive perspective from either macro-approach or micro-approach. In reality, a port itself is a complex and dynamic organization. Therefore, a comprehensive insight needs an integrated approach for the long-term national economic development. In this approach, the utmost importance is how to find the bottlenecks and to solve the problems effectively from the beginning stage in port development. In conclusion, derived from the macro- and micro-perspective. the attempt to establish an integrated approach is the merit of this study, which is required as a comprehensive measure since none of the two can be a solution independently. In terms of reinforcing this study, it needs further empirical research due to the restriction of the theoretical method of this paper. Consequently, the reinforced research will be able to enhance the integrated approach on the basis of the conceptual perspective.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.146.2-147
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• 2003

콩 발효식품은 예로부터 단백질 식품원으로서 뿐만 아니라, 식생활에서 없어서는 안되는 매우 중요한 식품 중의 하나였다. 발효식품에 대한 연구가 부진하였던 과거에는 콩 발효식품은 하나의 식품군으로서의 중요성을 가질 뿐 큰 관심의 대상은 아니었다. 그러나 최근에는 많은 연구자들이 콩 발효시 생성되는 기능성 성분 및 생리활성 효과를 점차 밝혀냄으로서 주목을 받기 시작하였다. 따라서 본 실험에서도 콩 발효에 의한 생리활성 효과를 알아보기 위해 Ames법에 의한 항돌연변이원 효과를 실험하였다. 콩 발효는 국산콩을 이용하여 메주에서 분리한 Bacillus sp. 와 Aspergillus sp.를 복합 발효시켜 동결건조 후, 분쇄하여 실험에 사용하였다. 제조된 발효 콩 분말은 일반분석을 행하였으며, 70% 에탄올로 3회 추출하여 감압농축 후, hexane, chloroform ethyl acetate, butanol 및 aqueous로 분획하여 동결 건조시킨 후, S. typhimurium TA98 및 TA100 균주를 이용한 유전자 복귀 돌연변이 시험을 실시하였다. 그 결과, 70% 에탄을 추출물과 각각의 분획물 자체의 돌연변이원성은 없었다. 또한 항돌연변이원 실험에서는 발암물질로서 직접 돌연변이원인 4NQO와 MNNG, 간접 돌연변이원인 Trp-P-1을 이용하였다. 특히 이들 발암물질 중 MNNG(0.4 $\mu\textrm{g}$/plate)의 경우 TA100 균주에서 ehtyl acetate 분획물에서 다른 분획물보다 높은 86.6%의 억제 효과를 나타내었으며, 대부분의 분획물에서도 70%이상의 억제효과를 나타내었다. 또한 각 분획물에서 농도 의존적으로 억제효과 역시 높았으며, 분획물에 따라 서로 다른 억제효과를 나타내었다.아 저장할 때 대비 저온저장고에서는 111일 동안에 11.7%의 중량감모가 발생하였으나, 신기술투입 저온저장고에서는 5.6%의 중량감모만이 발생하여 약 50%의 중량감모를 줄일 수 있었으며, 배의 색깔이나 경도도 대비구 보다 우수하였다. 4. 배를 비닐로 포장하여 대비 저온저장고에 저장한 경우와 비닐로 포장하지 않고 신기술투입 저온저장고에 저장한 경우를 비교할 때 11월~다음해 1월 까지는 중량감모, 과피색깔 및 경도에 큰 차이가 없었으나, 2월부터는 비닐로 포장하여 대비 저온저장고에 저장한 배의 품질변화가 급격히 증가되어 중량감모, 과피색깔 및 경도가 신기술 투입시 보다 급속하게 나빠졌다.를 저장 25일 경과시까지 유지하였다. 수확 시 높은 품온을 갖고 있는 과일을 산지에서 예냉 처리를 한 후 저온 냉장차를 이용하여 유통한다면 관행 유통 구조보다 고품질의 포도를 유통시킬 수 있는 것으로 사료되며 앞으로는 완숙된 고 당도(12.0~15.0Bx)$^{\circ}$ 포도를 수확 한 즉시 예냉 처리하고 저온 유통한다면 보다 신선한 과일을 소비자에게 전달 할 수 있을 것이다.갈변물질이 생성되었다. 이와 같은 결과로 볼 때, BAAG의 처리는 BAAC의 경우보다 가격은 저렴하면서도 항균력은 우수한 천연 항균복합제재로써 농산물 식품원료에 적용하여 선도유지 기간을 연장할 수 있는 효과를 기대할 수 있었다. 과일 등의 포장제로서 이용할 가능성을 확인하였다.로 [-wh] 겹의문사는 복수 의미를 지닐 수 없 다. 그러면 단수 의미는 어떻게 생성되는가\ulcorner 본 논문에서는 표면적 형태에도 불구하고 [-wh]의미의 겹의문사는 병렬적 관계의 합성어가 아니라 내부구조를 지니지 않은 단순한 단어(minimal $X^{0}$

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.6
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• pp.221-228
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• 2013

It is impossible directly to find a prime number p,q of a large semiprime n = pq using Trial Division method. So the most of the factorization algorithms use the indirection method which finds a prime number of p = GCD(a-b, n), q=GCD(a+b, n); get with a congruence of squares of $a^2{\equiv}b^2$ (mod n). It is just known the fact which the area that selects p and q about n=pq is between $10{\cdots}00$ < p < $\sqrt{n}$ and $\sqrt{n}$ < q < $99{\cdots}9$ based on $\sqrt{n}$ in the range, [$10{\cdots}01$, $99{\cdots}9$] of $l(p)=l(q)=l(\sqrt{n})=0.5l(n)$. This paper proposes the method that reduces the range of p using information obtained from n. The proposed method uses the method that sets to $p_{min}=n_{LR}$, $q_{min}=n_{RL}$; divide into $n=n_{LR}+n_{RL}$, $l(n_{LR})=l(n_{RL})=l(\sqrt{n})$. The proposed method is more effective from minimum 17.79% to maxmimum 90.17% than the method that reduces using $\sqrt{n}$ information.

• Parasites, Hosts and Diseases
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• v.34 no.2
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• pp.121-126
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• 1996

For the detection of Cwptospori,mum oocysts, fecal samples were collected from 201 calves which showed diarrhea. Among the 201 samples, 29 samples (14.4%) were positive for Cwptosporinium spry. by the DMSO-modified acid-fast stain (MAFS) , 23 samples (11.4%) were positive by commercial kit (Meridian Diagnostics, Cincinnati, Ohiol and 23 by the indirect immunofluorescence antibody (IFA )assay employing the monoclonal antibody (mAb C6). When tested by both IFA and MAFS, 20 fecal samples were positive for Cwptosporinium oocysts whereas 169 fecal samples were negative. If the MAFS is considered a standard method for oocyst detection, the IFA showed 69% of sensitivity and 98% of specificity. When tested by both IFA and commercial kit, 22 fecal samples were positive for Cwptospori,mum oocysts while 177 samples were negative. One sample tested by IFA was found to be false negative, when compared with the results by commercial kit. The sensitivity of IFA was calculated as high as 96%; the specificity as 99% and the predictive value was also 99%. In the present study, IFA employing the nAb C6 revealed that 23 samples (11.4%) were positive among the 201 calves showing diarrhea. Of 23 IFA positive samples, 4 samples (5%) showed cryptosporidial oocysts more than 105 OPG Therefore. it is concluded that the calves showing cryptosporidial oocysts more than 105 OPG in the feces were highly associated with clinical cryptosporidiosis.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.1
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• pp.9-16
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• 2020

The objective of this study is to propose closed-form solutions to the free vibration response of single-degree-of-freedom (SDOF) systems, as part of fundamental research on dynamic systems with Coulomb friction. The motion of a dynamic system with Coulomb friction is described by a nonlinear differential equation, and, due to the variation in the sign of friction force term with the direction of motion, it is difficult to obtain the closed-form solution. To solve this problem, the nonlinear differential equation is directly computed by numerical integration, or an approximated solution is indirectly obtained using a linear differential equation wherein the damping effect due to Coulomb friction is replaced by an equivalent viscous damping term. However, these conventional methods do not provide a closed-form solution from a mathematical point of view. In this regard, closed-form solutions to the free vibration response of SDOF systems with Coulomb friction are derived herein by considering that the sign of the friction force term is reversed in each half-cycle of motion and by expanding it to the entire time history using the power series function. In addition, for a given initial condition, both the number of free vibration half-cycles and the response at the instant when free vibration motion stops are predicted under the condition that the motion of free vibration is stopped when the amplitude of the friction force is higher than that of the restoring force due to stiffness.