• 한국철도학회논문집
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• 제16권5호
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• pp.418-429
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• 2013

본 연구는 우리나라에서 화물의 운송수단별로 통행시간가치가 어느 정도 크기로 수렴되는 것이 적정한 지를 평가해보고, 아울러 시간가치를 어느 정도의 범위 안에서 적용하는 것이 합리적인지를 강구하였다. 연구의 결과 화물차를 이용한 도로운송은 적정 시간가치의 크기와 범위의 도출이 가능하나, 철도와 내륙수로 해운, 항공운송 등은 도출에 한계가 있었다. 도로운송 화물의 적정 시간가치 크기는 20,000원/대 시간이며, 가변적 요소까지를 감안하였을 때 적용 가능한 범위의 분포는 17,000~23,000원/대 시간이다. 아울러 시간가치의 산정 방법은 도로운송의 경우 임금율법이 적정하나 철도, 내륙수로, 해운, 항공 운송 등은 적용 목적과 대상 화물의 특성을 반영하여 한계대체율법을 사용하는 방안이 합리적임을 제시하였다.

• 한국환경과학회지
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• 제22권4호
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• pp.453-461
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• 2013

This study, changes in raw water quality is to indicate on the efficiency of ozone treatment of each pollutant as compared to derive the appropriate operating measures. The appropriate selection for injection rate of pre-ozone and did not inject pre-ozone assess changes in the water. When good water quality, you not injected of pre-ozone to evaluate the economic efficiency of electricity and put the most cost-effective ozone concentration were evaluated. Evaluation remove organic matter and chlorophyll-a concentration level in experiments with each factor of the water DOC> 2.5 mg/L, THMFP> 70 ${\mu}g/L$, Chl-a> 30 $mg/m^3$or less constant process, if you do not need to put pre-ozone showed little impact. It also does not put you in pre-ozone appropriate produce enough power rate savings was calculated as approximately 90 million won. Ability to remove organic materials and the ability to produce disinfection byproducts, and cost-effective decisions by considering the concentration of injection if pre-ozone 1 mg/L was investigated by the appropriate concentration of ozone injection.

• 대한기계학회논문집A
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• 제33권6호
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• pp.607-613
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• 2009

In this paper, we made a simple paper feeding system which is one of MTS (media transport system) and controllers. The plant has a flexible paper and two driving rollers and two driven rollers. The control system has two conventional PID controllers. Skew angle and feeding speed of MTS deteriorate the quality of feeding system. In order to control a feeding speed and skew of feeding paper, we control rotational velocity of two driving rollers. Therefore, this controller has two inputs and two outputs as MIMO (multi-input and multi-output) system. The control inputs were the feeding speed and the skew displacement of the paper. The control outputs were the rotational velocity to each driving roller. To find appropriate PID gains of two controllers, we proposed an optimization technique. We assume the system variables and performance of a whole system as follows. PID gains of two controllers for skew and feeding speed are system variables. System performance is both skew and feeding speed. We simulates to making mathematical correlation using global Kriging interpolation. To find appropriate value of system variables, optimization method is simulation in sequence as following method. First, the optimization solver simulates with DOE (design of experiment) tables to find correlation equation of both system variable and performances. Then, the solver guesses the appropriate values and simulates if the system variables are appropriate or not. If the result of validation doesn't satisfy the convergence and iteration tolerance, the solver makes a new Kriging models and iterates this sequence until satisfy the tolerances.

• Journal of Astronomy and Space Sciences
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• 제28권3호
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• pp.183-192
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• 2011

The current study analyzes the effects of the scaling parameters of the batch unscented transformation on precision satellite orbit determination. Satellite laser ranging (SLR) data are used in the orbit determination algorithm, which consists of dynamics model, observation model and filtering algorithm composed of the batch unscented transformation. TOPEX/Poseidon SLR data are used by utilizing the normal point (NP) data observed from ground station. The filtering algorithm includes a repeated series of processes to determine the appropriate scaling parameters for the batch unscented transformation. To determine appropriate scaling parameters, general ranges of the scaling parameters of ${\alpha}$, ${\beta}$, k, $\lambda$ are established. Depending on the range settings, each parameter was assigned to the filtering algorithm at regular intervals. Appropriate scaling parameters are determined for observation data obtained from several observatories, by analyzing the relationship between tuning properties of the scaling parameters and estimated orbit precision. The orbit determination of satellite using the batch unscented transformation can achieve levels of accuracy within several tens of cm with the appropriate scaling parameters. The analyses in the present study give insights into the roles of scaling parameters in the batch unscented transformation method.

• 한국산학기술학회논문지
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• 제19권1호
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• pp.1-11
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• 2018

다양한 공학분야의 최적화 문제를 해결하기 위해 적절한 매개변수를 설정하기란 번거로운 작업이며, 매개변수 민감도 분석을 통해 적절한 매개변수를 설정하더라도 설정된 매개변수가 모든 문제에 적절한지 판단하기에는 한계가 있다. 이러한 이유로 매개변수를 문제에 따라 적절하게 설정하는 매개변수 자동검보정 (Self-adaptive) 화음탐색 알고리즘이 개발되고 발전하고 있다. 본 연구에서는 지금까지 개발된 자가적응형 하모니서치를 조사하고 그의 특성을 해탐색, 설정 매개변수, 적용성 등으로 구분하였으며, 이 중 매개변수 설정의 번거로움을 없애고, 적절한 매개변수 설정을 통해 해의 성능 향상을 위해 개발 된 6 가지 자가적응형 화음탐색 알고리즘을 선택하여 비교 분석을 수행하였다. 최적화 결과의 객관적인 비교를 위해 대표적인 수학적, 공학적 최적화 문제를 모두 적용 하였고, 다양한 성능 지수 (Performance index)를 사용하여 각 알고리즘의 성능을 정량적으로 비교하였다. 이것은 향후 신규 최적화 알고리즘을 개발하거나 해 탐색의 성능을 향상시키는 연구에 도움이 될 것으로 기대된다.

• 상하수도학회지
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• 제21권5호
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• pp.641-647
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• 2007

This study aims to find out optimum condition for hydrogen production and organic removal when treating food and swine wastewater together. For this purpose, various batch tests were conducted by changing mixture ratio from 6:4 (food wastewater:swine wastewater) to 1:9 without pretreatment process. For hydrogen production through anaerobic fermentation, the mixture ratios of R-1 (6:4), R-2 (5:5) and R-6 (1:9) were out of pH range appropriate for hydrogen production and mixture ratios of R-3 (4:6), R-4 (3:7), and R-5(2:8) showed appropriate hydrogen production where their pH ranges were 5.1~5.5. Especially in case of R-3, it consistently maintained appropriate pH range for hydrogen production for 72hr and produced maximum hydrogen. The characteristics of hydrogen production and cumulative hydrogen production according to each mixture ratio showed that R-1, R-2 and R-6 did not produce any hydrogen, and maximum hydrogen productions of R-3, R-4 and R-5 were 593ml, 419ml and 90ml, respectively. Total cumulative hydrogen productions of R-3, R-4 and R-5 were 1690ml, 425ml and 96ml, respectively. Based on previous results, it was concluded that, the most appropriate mixture ratio of food wastewater and swine wastewate rwas 4:6 (R-3). The experiment for COD removal rate to evaluate organic removal efficiency revealed that R-3, R-4 and R-5 showed high removal efficiencies during the highest hydrogen production amount and the highest efficiency was 41% with R-3.

• 한국초등과학교육학회지:초등과학교육
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• 제25권3호
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• pp.307-317
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• 2006

Those students with ability and interest in science should be supported to develop their potential and to reach high levels of achievement in science and technology. In order to ensure that gifted pupils are able to enhance their creativity as well as research abilities, appropriate learning programs and environments are essential. One of the various teaching and learning models for the gifted in science is the discovery learning model based on inductive science activities. There is a clear line of continuity between knowledge discovery at the forefront of research and student's learning activities. If students receive excellent training in organizing scientific concepts for themselves, they will be able to skillfully apply appropriate scientific concepts and solve problems when facing unfamiliar situations. It is very important to offer an appropriate learning environment to maximize the learning effect whilst, at the same time, understanding individual student's characteristics. In this study, the authors took great pains to research effective learning environments for gifted science students. Firstly, appropriate classroom learning environments thought by the teacher to offer the most potential were investigated. 3 different classes in which a revised teaching and learning environment was applied in sequence were examined. Inquiries were conducted into students' activities and achievement through observation, interviews, and examination of students' worksheets. A Science Education expert and 5 elementary school teachers specializing in gifted education also observed the class to examine the specific character of gifted science students. A number of suggestions in discovery learning classes for elementary students gifted in science are possible; 1) Readiness is essential in attitudes related to the inquiry. 2) The interaction between students should be developed. A permissive atmosphere is needed in small group activities. 3) Students require training in listening to others. In a whole class discussion, a permissive atmosphere needs to be restricted somewhat in order to promote full and inclusive discussion. 4) Students should have a chance to practice induction and abduction methods in solving problems.

• 대한인간공학회지
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• 제29권1호
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• pp.39-46
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• 2010

The growth of function in vehicle needs complex display and control system, the In-Vehicle Information System(IVIS). Although current IVISs are widely implemented in commercial vehicles, a new form of IVIS has been recently studied in order to reduce drivers' workloads. The purpose of this study is to suggest an appropriate menu structure of a new type IVIS, to be implemented on the instrument cluster panel, using Taguchi's parameter design. In the research, firstly, functions were selected that are appropriate to control through the instrument cluster among existing functions of current IVISs by quantitative evaluation of ergonomic principles. Then, menu structure alternatives were extracted by investigating priorities to those functions selected. Finally, menu structure alternatives were evaluated through an experiment and suggest the most appropriate one by applying Taguchi's parameter design. Taguchi method was used not only for planning an experiment but also evaluating alternatives. SN ratios were a key value to evaluate the alternatives and to find the most proper one. Through the research, the most appropriate menu structure for the instrument cluster IVIS was finally suggested among the alternatives and it is expected that the results of this research could provide a guideline to the instrument cluster IVIS.

• 대한한의학방제학회지
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• 제25권1호
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• pp.89-101
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• 2017

Objectives : This study was done to suggest appropriate number and time of dispensing herbal medicine for each Korean pharmacist. Methods : For this study, we visited one herbal dispensary institution which was considered as one of the biggest herbal dispensary preparing the largest number of prescription. We observed the work in the dispensary and recorded time for preparing prescriptions of 5 Korean Pharmacists. And we also recorded time for preparing prescriptions with toxic medicinal herbs of each Korean Pharmacist. Investigation has been done for 3 weeks, from 11, Jan. to 4, Feb. in 2016. Results : The whole dispensed prescription number of 5 Korean Pharmacists during 3 weeks were 899. These prescriptions include toxic medicinal herbs and general prescriptions. Ratio of prescriptions including toxic medicinal herbs was 38.4% while general prescriptions was 61.6%. Average direct dispensing time for herbal prescription of Korean pharmacists were 6.2 minutes. Applied personal allowances, appropriate number for dispensing in each day was 22.7. With allowances rate in general workplace, appropriate number for preparing was 20.5. According to ILO allowances regulation, appropriate number for preparing was 18.8. Conclusions : Suggested number of dispensing herbal medicine per day for each Korean pharmacist was 20.5. Applying this would be beneficial for development of Korean medicine circumstances.

• 한국산학기술학회논문지
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• 제18권12호
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• pp.685-696
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• 2017

성당의 공간이미지를 조성함에 있어, 시각을 통해 심성을 변화시키는 가장 중요한 요인은 빛이라고 할 수 있다. 그리고 공간의 깊이는 빛에 의한 음영에 의해 만들어진다. 미사와 같은 종교적 행사가 행해지는 장소에 있어서 음영에 의한 깊이의 변화와 위계설정은 집중도와 신비로움 또는 성스러움의 분위기를 확보하는 데에 중요한 계획조건이 된다고 할 수 있다. 따라서 빛이 가진 종교적 의미와 인간 감성에 미치는 영향은 매우 크다고 할 수 있으며, 이에 본 연구에서는 성당의 예배공간 조명계획에 대한 요소 중 '조도'를 그 중요요소로 보았다. 조도는 시각적 환경조성에서 미묘한 공간구성상의 차이를 통해 대상과 공간의 형태, 명료함을 부여함으로써 표현된다. 조명을 통해 공간분위기를 적정한 수준에서 관리하게 되고, 공간의 존재를 확인함에 조도의 역할은 필수적이라고 할 수 있을 것이다. 이에 따라, 관련 기준을 종합 분석하여 조도의 기준과 범위를 설정하고, 현대적인 디자인 적용이 시작되었다고 할 수 있는 80년대 이후 서울 강남지역에 건립된 성당들을 대상으로 조도와 관련된 요소들을 분석하고 각 성당의 전례공간과 회중석의 조도를 측정하여 이를 비교분석함으로써 적정수준의 적용여부를 검토확인하고 이를 추후 계획지침으로 활용하도록 제안하고자 하였다.