• Journal of the Earthquake Engineering Society of Korea
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• v.13 no.3
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• pp.11-19
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• 2009

Recently, concerns relating to the maintenance of large structures have been increased. In addition, the number of large structures that need to be evaluated for their structural safety due to natural disasters and structural deterioration has been rapidly increasing. It is common for the structural characteristics of an older large structure to differ from the characteristics in the initial design stage, and changes in dynamic characteristics may result from a reduction in stiffness due to cracks on the materials. The process of deterioration of such structures enables the detection of damaged locations, as well as a quantitative evaluation. One of the typical measuring instruments used for the monitoring of bridges and buildings is the dynamic measurement system. Conventional dynamic measurement systems require considerable cabling to facilitate a direct connection between sensor and DAQ logger. For this reason, a method of measuring structural responses from a remote distance without the mounted sensors is needed. In terms of non-contact methods that are applicable to dynamic response measurement, the methods using the doppler effect of a laser or a GPS are commonly used. However, such methods could not be generally applied to bridge structures because of their costs and inaccuracies. Alternatively, a method using a visual image can be economical as well as feasible for measuring vibration signals of inaccessible bridge structures and extracting their dynamic characteristics. Many studies have been conducted using camera visual signals instead of conventional mounted sensors. However, these studies have been focused on measuring displacement response by an image processing technique after recording a position of the target mounted on the structure, in which the number of measurement targets may be limited. Therefore, in this study, a model experiment was carried out to verify the measurement algorithm for measuring multi-point displacement responses by using a DIC (Digital Image Correlation) technique.

• Proceedings of the Korea Association of Information Systems Conference
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• 2004.11a
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• pp.349-365
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• 2004

기업의 또는 부문에서 구축된 각 정보시스템들은 시간이 지남에 따라 기업의 경쟁우위를 확보하기 위해 통합의 필요성이 증대하게 되었는데, 이러한 필요에 의해 제기된 것이 ERP(Enterprise Resource Planning: 전사적 자원관리)이다. 급변하는 기업의 내${\cdot}$외부 환경에 대해 신속하게 대응하기 위해 ERP 시스템을 도입하는 기업들의 수가 증가함에도 불구하고 ERP 원가관리시스템에 대한 연구는 아직까지 그 범위가 한정되었다고 할 수 있다. 본 논문은 ERP 도입 현황 및 원가관리시스템의 도입${\cdot}$설계현황자료를 바탕으로 하여, 중소기업의 ERP 원가관리시스템의 성공적 도입을 위한 방향을 제시하고자 한다. 중소기업에서 ERP 원가관리시스템을 도입할 때는, 원가관리시스템의 특성과 구축 목표, 구조 설계, 원가대상 설정 등과 관련된 다음과 같은 사항들을 고려하여야 성공적인 시스템을 구축할 수 있을 것이다. 첫째, ERP 원가관리시스템 특성 분석단계에서는 원가정보를 구성하는 내용의 충실성뿐만 아니라 정보가 전달${\cdot}$제공되는 범위와 대상의 적합성과 함께 그 표현의 형식 또한 고려되어야 한다. 둘째, ERP 원가관리시스템 구축목표 설정단계에서는 인가관리정보의 산출요건에 대한 명확한 이해와 목표설정을 기반으로 해야 한다. 셋째, ERP 원가 관리시스템 구조 분석 및 선계단계에서는 생산관리시스템 및 원가대상 설정 분석이 이루어져야 한다. 넷째, ERP 원가관리시스템 구현단계에서는 원가관리시스템과 타 계열시스템과의 인터페이스를 고려해야 한다. 따라서 원가관리시스템의 구현 시에는 관련시스템에서 어떠한 정보론 인터페이스 받을 것인가를 명확히 하여 시스템 가동 시에 타 관련시스템과 원활한 연계가 되도록 함으로써 전사적 종합시스템이 되도록 하여야 학 것이다.RS와 제진장치에 대한 전체적인 성능평가를 성공적으로 수행하였으며, 운전결과 및 경험은 향후 상용설비를 위한 기본자료로 활용할 것이다.X>, 그리고 입원기간은 $21.6\pm14.3일(13\~56)$이었다. 수술 후 평균 CK-MB는 $11.3\pm14.1ng/mL$였다. 수술 후 조기 혈관 개존율은 $100\% (24/24)$였다. 모든 환자에서 완전 추적이 가능하였으며 평균 추적기간은 $20.4\pm15.2개월(5\~43)$이었다. 이 기간 중 사망환자나 흉통이 재발한 환자는 없었다. 걸론: 80세 이상 고령의 환자에서 OPCAB은 수술 후 합병증을 줄이고 좋은 결과를 보여 주었다. 그러므로 고령의 환자에서도 관상동맥우회술의 적응증이 되면 적극적으로 수술을 시행할 필요가 있으며, 수술방법은 OPCAB이 좋을 것으로 생각한다서 실용적 개발의 가능성을 보였다.에 따라 현저한 차이가 있었으며 Dimethoate처리$(30^{\circ}C,\; 0.2\%$액에서 24시간)에 의하여 볍씨의 호흡량이 감소되었다. 9) 산소호흡량과 평균발아소요일수와는 $\gamma=-0.945$로 부의 유의한 상관을 보였는데 산소호흡량이 많은 품종은 평균발아소요일수가 짧은 경향을 보였다. 10) 볍씨의 산소호흡량과 Dimethoate 처리에 의한 볍씨의 발아저해도와는 $\gamma=-0,771$의 높은 부의 상관을 보였으며 산색호흡량이 많은 품종이 발아저해도가 낮고 적은 품종에서는 높았다. 현재까지는 그 활동이 11.2년의 주기성을 보여주지만 그 이전에 있어서는 그 활동이 극히 약화되었을 뿐만 아니라 매우 불규칙하다는 것이 Schneider와 Mass(1975)에 의해 밝혀졌다. 결국 1710년대부터 현재까지 우리나라에 있어서 벼멸구와 흰

• Journal of the Korean Data and Information Science Society
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• v.27 no.5
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• pp.1375-1387
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• 2016

The purpose of this study was to evaluate the effect of exercise on cognitive function in the elderly through a systematic literature review and meta-analysis. For the study purpose, 14 studies were selected through a systematic process of using several databases and 11 studies were used to estimate the effect size of exercise on cognitive function. Meta-analysis was performed using a random effects model, and the effect size on cognitive function was calculated. The effect size for cognitive function of exercise intervention was Hedges' g=1.05 (95% CI: 0.61~1.50), indicating a large effect size. For heterogeneity, moderator analysis was performed using intervention, number of times per week, intervention duration, and cognitive function measurement. Cognitive function measurement was statistically significant, the other moderators did not significant difference. Results support that exercise has significant positive effects on cognitive function in elderly in korea. It also provided a basis that can be applied to exercise intervention design for cognitive function.

• Journal of The Korean Association For Science Education
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• v.36 no.3
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• pp.499-507
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• 2016

A flipped learning class was held in an attempt to overcome the limits of lecture-type classes in pre-service science teacher training and to provide a student-oriented education suitable for digital native generation. The principles of teaching-learning in flipped learning were applied to the general ADDIE model to design the class; learning materials were developed accordingly. The developed flipped learning materials and class design were verified for their validity using an expert panel's Delphi method and validity test, in which the validity was verified with 0.75 CVR. The developed flipped learning materials were applied to the theory of science education and the instructional effectiveness was analyzed. The results suggest that the students' motivation to study, interest, and confidence in learning increased; however, their satisfaction in class decreased by 30% as compared to the lecture-type class and their self-confidence in the improvement of their academic achievement was not sufficient. In order for a flipped learning class to be successful, the class should be small in size, which would ensure appropriate teacher-student communication and individualized learning; also, the students' burden of learning should be reduced and accessibility to video materials for pre-class learning should be reinforced.

• Journal of Korean Society of Forest Science
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• v.77 no.3
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• pp.322-330
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• 1988

This study was analyzed the behavior of recreational use through interviewing visitors with the questionnaire (1986.11-1987.9) in Mt. Kyeryong National Park. The number of visitors have been forecasted by tune series data of the past number of visitors, population, GNP, and number of cars (1974-1986) in korea. The results of the study can be summarized as follows : 1) Visitor's subjective evaluation about recreational environment evaluated to be fair in Mt. Kyeryong National Park. 2) They preferred natural forest resources to historic remains, tourist facility, etc.. 3) Number of participation was mostly once or five times over. 4) Visitors were affirmative to re-visit to the Mt. Kyeryong National Park. 5) Most of visitors stay for one day. 6) The most suitable estimated user regression model was : Y=-5753.7350+0.1726 Pop. -0.6564 NO. of Car. According to this equation, the total number of visitors will he increased by 3% per year from 1,023 thousands people in 1987 to 1,698 thousands in 2000.

• Journal of Korean Society of Forest Science
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• v.85 no.1
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• pp.56-65
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• 1996

Current volume tables might underestimate or overestimate the volumes of individual trees in a specific region because the tables were made using the data from broad region. This study provides a statistical method of local correction, which is the ratio-of-means estimator, when the table is applied to the data from a specific region. Data used in this study were 411 trees of Larix leptolepis from Hongchon region. Five statistical models for individual tree volume equation were evaluated based on 3 evalation criteria and the best equation fitted to the data from Hongchon region was selected. The volume estimated by the selected equation was then compared with the volume estimated by the current volume table. From the ratio-of-means estimate based on the volumes estimated by selected equation and by current volume table, the local correction was made. The correction equation was $V_{Hongchon}=1.078$ $V_{volume\;table}$. It is also proved that the correction equation can simply and precisely estimate tree volumes of Larix leptolepis in Hongchon region using the current volume table.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.16 no.4
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• pp.439-450
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• 2003

Flat plate system has been adopted in many buildings constructed recently because of the advantage of reduced floor heights to meet the economical and architectural demands. Structural engineers commonly use the effective beam width model(EBWM) in practical engineering for the analysis of flat plate structures. However, in many cases, when it is difficult to use the EBWM, it is necessary to use a refined finite element model for an accurate analysis. But it would take significant amount of computational time and memory if the entire building structure was subdivided with finer meshes. An efficient analytical method is proposed in this study to obtain accurate results in significantly reduced computational time. The proposed method employs super elements developed using the matrix condensation technique and fictitious beams are used in the development of super elements to enforce the compatibility at the interfaces of super elements. The stiffness degradation of flat plate system considered in the EBWM was taken into account by reducing the elastic modulus of floor slabs in this study. Static and dynamic analyses of example structures were performed and the efficiency and accuracy of the proposed method were verified by comparing the results with those of the refined finite element model and the EBWM.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.4
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• pp.419-425
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• 2014

The current work investigated the variation of numerical solutions according to the grid number, the distance of the first grid point off the ship surface, turbulence modeling and discretization. The subject vessel is KVLCC. A commercial code, Gridgen V15 and FLUENT were used the generation of the ship hull surface and spatial system and flow computation. The first part of examination, the effect of solutions were accessed depending on the grid number, turbulence modeling and discretization. The second part was focus on the suitable selection of the distance of the first grid point off the ship surface: $Y_P+$. When grid number and discretization were fixed the same value, the friction resistance showed differences within 1 % but the pressure resistance showed big differences 9 % depending on the turbulence modeling. When $Y_P+$ were set 30 and 50 for the same discretization, friction resistance showed almost same results within 1 % according to the turbulence modeling. However, when $Y_P+$ were fixed 100, friction resistance showed more differences of 3 % compared to $Y_P+$ of 30 and 50. Whereas pressure resistance showed big differences of 10 % regardless of turbulence modeling. When turbulence modeling and discretization were set the same value, friction, pressure and total resistance showed almost same result within 0.3 % depending on the grid number. Lastly, When turbulence modeling and discretization were fixed the same value, the friction resistance showed differences within 5~8 % but the pressure resistance showed small differences depending on the $Y_P+$.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.1-11
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• 1991

A hull form for an Aframax tanker whore form parameters cover the values of $C_B{\simeq}0.8,\;L/B{\simeq}5.5\;and\;B/d{\simeq}3.5$ has been developed by applying a composite stern frameline concept and its excellent performance has been evaluated through a series of model tests at the Korea Research Institute of Ships and Ocean Engineering. The tests showed that this concept was very much promising in the cases of wide breadth and shallow draught vessels and suitably applicable to the stern frameline shape. For the comparison, a hull form developed by Japanese 'H' yard has been selected and the performances of two hull forms were evaluated by model tests and theoretical calculations. The comparison shows that Daewoo hull form requires less effective power by 10% and less delevered power by 5-6% at both full load and ballast conditions. In addition, it is suggested that Hushes method can give better correlationthan Froude method because the full scale resistance extrapolated by Froude method would be very much optimistic in case of the hull form with very low value of form factor.

• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.213-217
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• 2005

Adult development and fecundity of the green peach aphid, Myzus persicae $S\H{u}lzer$, were studied at $15{\sim}32.5^{\circ}C$ with $60{\sim}70%$ RH under 16L:8D and the results were put together to build a life table. The longevity shortened as temperatures rose at and below $25^{\circ}C$ whereas it remained relatively constant at $27.5^{\circ}C$. Total fecundity was not significantly different at all temperatures except at $30^{\circ}C$. Daily fecundity gradually increased from $15\;to\;22.5^{\circ}C$. It was 5.1 at $25^{\circ}C$ and as temperatures either went down or up, it decreased to 2.8 at both $15^{\circ}C\;and\;30^{\circ}C$. Fecundity model built from total fecundity at various temperatures suggests that $18.3^{\circ}C$ was the optimum temperature for the maximum progeny of 51. Net reproduction rate RO was highest of 36.5 at $27.5^{\circ}C$. The intrinsic rate of increase per day $r_m$ and the finite rate of increase per day $\lambda$ were highest of 0.4 and 1.6, respectively and the doubling time Dt was shortest of 1.6. Constructed life table suggests that the optimum temperature for adult development for the green peach aphid was $27.5^{\circ}C$ at which the mean generation time was 8.1.