• 농촌지도와개발
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• 제22권3호
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• pp.285-292
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• 2015

Recently, the demand of rural tourism has been increased to promote farm household income and rural economy. Korean government has supported to promote rural tourism. One of the most difficult tasks in estimating the economic impact of the tourism industry is how the industry should be defined in terms of an economic sector, since tourism is not defined in national Input-Output (I-O) tables or in the Standard Industrial Classification code. Moreover, there is no specified Standard Industrial Classification for rural tourism. The purpose of the study aims to examine specified Standard Industrial Classification of rural tourism using the I-O model analysis to estimate the economic impacts of rural tourism. Results showed that there were two components considered as inputs. One is the inputs that final demand can move to input of rural tourism in I-O tables. The other is one that the final demand was provided by farm household as intermediate inputs.

• 한국수학교육학회지시리즈A:수학교육
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• 제48권3호
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• pp.329-352
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• 2009

The purpose of this study was to investigate the effects of small group cooperative communicative activities on the strategies for estimating measurement. To do this, two research questions were set as follow: First, are there any differences between strategies employed by students in the experimental group and the control group before and after the estimating measurement activities? Second, are there any differences between strategies employed by students in different ability levels(upper, middle, lower) of pre-estimating measurement test in the experimental group? The research results were drawn from the investigation as below: First, the strategical change of before and after the estimating measurement tasks in the experimental group was quite noticeable. Unlike the small strategical change in the control group, small group cooperative communicative learning resulted in a decrease of simple memorization and guessing strategies and an increase of refined strategies such as the standard strategy, clustering, unit load and so on. Second, mathematical communicative activities in a small group cooperative learning showed that the students in the upper level of pre-estimating measurement test used more refined strategies and the students in the lower level used simple memorization and guessing strategy more frequently. And through interaction in small group, students could have chances to recognize error of strategies and to modify and learn strategies. In conclusion, small group cooperative activities allowed students to have chances to communicate mathematically and it is a efficient way of helping students learn estimating measurement strategies.

• 한국추진공학회지
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• 제13권1호
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• pp.10-18
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• 2009

본 연구에서는 평행 벽 제트-노즐 형상의 막냉각 수치해석에 적합한 난류모델을 선정하고자 하였다. 현재 실험을 하기 위한 전 단계이므로, 먼저 유사한 참고 형상에 대해 Standard $k-{\epsilon}$ 모델과 RNG $k-{\epsilon}$ 모델, SST $k-{\omega}$ 모델, 그리고 RSM 모델 등 다양한 난류모델을 적용하였고, Near-wall 처리 방법으로서 SST $k-{\omega}$ 모델을 제외하고는 Standard wall functions와 Enhanced wall functions 등 2종류를 각각의 모델에서 사용하였으며, 실험값과 비교하여 보다 적합한 난류모델을 선정하고자 하였다. 나아가 2차원 축대칭으로 평행 벽 제트-노즐 단일 슬롯 형상에 대해 기선정한 난류모델을 적용하여 막냉각 특성을 살펴보았다. 유사 참고 형상에 대한 해석 결과 Standard $k-{\epsilon}$ 모델 및 RSM 모델이 거의 비슷한 성능을 보여주었으나 수렴성이 우수한 Standard $k-{\epsilon}$ 모델이 선정되었다. 또한 Standard wall functions를 사용하는 것보다 Enhanced wall functions를 사용하는 것이 더 좋은 결과를 보여주었다. 나아가 평행 벽 제트-노즐 단일 슬롯 형상에 적용한 결과 물리적으로 타당한 막냉각 특성을 보여주었다. 선정된 모델 및 해석방법론을 이용하여 평행 벽 제트-노즐 다단 슬롯 형상에 대한 막냉각 해석을 수행할 예정이며, 관련 결과는 추후 실험 예비해석 방법론으로 활용할 예정이다.

• 한국경영과학회지
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• 제39권1호
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• pp.1-12
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• 2014

This article proposes a variable sampling interval (VSI) $\bar{X}$ control chart using weighted standard deviation (WSD) method for skewed populations. The WSD method decomposes the standard deviation of a quality characteristic into upper and lower deviations and adjusts control limits and warning limits of a control chart in accordance with the direction and degree of skewness. A control chart constant is derived for estimating the standard deviation of skewed distributions with the mean of sample standard deviations. The proposed chart is compared with the conventional VSI $\bar{X}$ control chart under some skewed distributions. Simulation study shows that the proposed WSD VSI chart can control the in-control average time to signal (ATS) as an adequate level better than the conventional VSI chart, and the proposed chart can detect a decrease in the process mean of a quality characteristic following a positively skewed distribution more quickly than the standard VSI chart.

• 센서학회지
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• 제17권2호
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• pp.87-94
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• 2008

Blood pressure (BP), one of the most important vital signs, is used to identify an emergency state and reflects the blood flow characteristics of the cardiovascular system. The conventional noninvasive method of measuring BP is inconvenient because patients must wear a cuff on their arm and the measurement process takes time. This paper proposes an algorithm for estimating the BP using the pulse transit time (PTT) of the photoplethysmography (PPG) and pressure pulse from finger at the same time as a more convenient way to measure the BP. After recording the electrocardiogram (ECG), measuring the pressure pulse, and performing PPG, we calculated the PTT from the acquired signals. Then, we used a multiple regression analysis to measure the systolic and diastolic BP indirectly. Comparing the BP measured indirectly using the proposed algorithm and the real BP measured with a sphygmomanometer, the systolic pressure had a mean error of ${\pm}3.240$ mmHg and a standard deviation of 2.530 mmHg, while the diastolic pressure had a satisfactory result, i.e., a mean error of ${\pm}1.807$ mmHg and a standard deviation of 1.396 mmHg. These results are more superior than existing method estimating blood pressure using the one PTT and satisfy the ANSI/AAMI regulations for certifying a sphygmomanometer i.e., the measurement error should be within a mean error of ${\pm}5$ mmHg and a standard deviation of 8 mmHg. These results suggest the possibility of applying our method to a portable, long-term BP monitoring system.

• 한국건설관리학회논문집
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• 제13권2호
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• pp.3-10
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• 2012

현행 "건설기술관리법" 시행규칙의 환경보전비 세부산출기준에 따르면 환경보전비는 표준품셈 등을 이용하여 원가계산에 따라 산출하거나 원가계산이 곤란한 경우에는 공종별로 직접비에 요율을 적용하여 산정하도록 규정하고 있다. 그러나 원가 계산으로 산정할 경우, 현행 표준품셈에 환경보전비에 해당하는 항목이 일부 제한된 항목만 명시되어 있어 다양한 환경오염 방지시설의 설치 및 운영에 사용되는 제반비용을 반영하는 데 현실적인 제약이 있다. 아울러 요율을 적용하여 산정하는 경우에도 공종별로 획일적인 요율을 적용하도록 규정되어 공사현장의 입지여건 등에 따른 특성을 제대로 반영하지 못하고 있어 공사현장의 효율적인 환경관리가 어려운 실정이다. 따라서 본 연구에서는 도로공사 건설현장을 대상으로 공사규모, 현장 입지조건, 환경보전비 계상방식 등에 대하여 실태 조사 및 분석을 실시하여 이를 토대로 환경보전비의 적정 계상 방안을 제시하고자 한다.

• 대한지역사회영양학회지
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• 제15권6호
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• pp.760-775
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• 2010

This study was performed to investigate the validity of food photographs for estimating individuals' dietary intakes and compare it with other dietary assessment methods. Subjects were 7 professors, 2 researchers, 12 dietitian and 16 graduate students majoring in food and nutrition. Among the subjects, 20 subjects had research experiences in the dietary intake survey more than one year while 17 had not. Each subject estimated 50 food portions displayed in computer monitor by comparing with standard food photographs, which were weighed portions of 28 foods from typical Korean diet. No significant differences between the estimated value and the weighed value of 17 (34%) food portions were shown in research-experienced group and those of 14 (28%) food portions were shown in no-researchexperienced group. 24-hour recall was the most frequently-used method for dietary assessment followed by in the order of food frequency questionnaire, dietary record, diet history and weighing method. After estimating food portions by photographs, 30 subjects (81%) were willing to use the method for dietary assessment because of its convenience and easy communication between researcher and subject. This study suggests that digital photography method would be a useful and convenient new instrument for estimating individuals' dietary intake. However, it is necessary to create standard database for food portions and carry out systematic education for food estimation in order to apply this method in the fields.

• The Korean Journal of Physiology and Pharmacology
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• 제16권2호
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• pp.97-106
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• 2012

The pharmacokinetics/pharmacodynamics analysis software NONMEM$^{(R)}$ output provides model parameter estimates and associated standard errors. However, the standard error of empirical Bayes estimates of inter-subject variability is not available. A simple and direct method for estimating standard error of the empirical Bayes estimates of inter-subject variability using the NONMEM$^{(R)}$ VI internal matrix POSTV is developed and applied to several pharmacokinetic models using intensively or sparsely sampled data for demonstration and to evaluate performance. The computed standard error is in general similar to the results from other post-processing methods and the degree of difference, if any, depends on the employed estimation options.

• 한국IT서비스학회지
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• 제17권3호
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• pp.101-115
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• 2018

In order to promote the IT business efficiently, the Preliminary Feasibility Study has been conducted since 2004. It is to verify the feasibility of a large-scale IT project in advance and to determine whether to reflect the budget. It is more difficult to analyze the benefits of the IT project than other projects, because the IT project is carried out by combining tangible and intangible assets and human resources. For this reason, the Standard Guideline for Preliminary Feasibility Study in the IT field suggests a framework to support in estimating the benefits of the IT project. However, it includes the following problems : 1) level discrepancy among the benefit categories, 2) lack of types of benefit items, 3) no consideration of benefit inducing factors. So the framework is facing a low utilization. This study develops a new framework through a three-step research process. The new framework can be used not only for preliminary feasibility studies but also for estimating the benefits of general IT projects.

• 한국군사과학기술학회지
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• 제13권1호
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• pp.84-90
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• 2010

Korean army currently considers the development of the new generation MLRS(Multiple Launcher Rocket System) as a new alternative, which responses on the renovation of the artillery and future battlefield environment. This study suggests that it presents cost-effectiveness of MLRS based on the Analytic Hierarchy Process and Parametric Estimating(PRICE H). According to this study, the cost-effectiveness of new generation MLRS presented that alternative A is 2.30 times and alternative B is 1.70 times, which are better than currently operating M270A1. Therefore, The best acquisition is alternative A that launcher is carried on currently operating 10ton standard truck but final acquisition alternative should be politically decided to consider viability of operator, performance and the latest of equipment.