• Title/Summary/Keyword: two-time-scale system

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A Evaluation System Integrating Cost-Cross Effects of Big Scale R&D Projects (R&D프로젝트군의 우선순위 결정을 위한 비용 - 상호효과 통합평가시스템)

  • Kwon, Cheol-Shin;Lee, Soon-Cheon;Park, Jooh-Ho
    • Journal of the Korean Operations Research and Management Science Society
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    • v.32 no.2
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    • pp.163-175
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    • 2007
  • [ $ulcorner$ ]Cost-Effectiveness Analysis$\lrcorner$ has been wifely used to evaluate economic efficiency of R&D projects, but most of cost-effectiveness evaluation systems have some problems such as systematic method for setting and evaluating cost factors, estimation of single effect on each R&D project, and estimation of cross effects among R&D projects. To solve these problems, we have designed a new evaluation indicator called a $ulcorner$Cost-Cross Effect Integration Indicator$lrcorner$ including cross effects developed in this research. The major research findings are summarized as follows : (1) $ulcorner$Coist Estimation Model$lrcorner$, which estimates the cost factors divided into two classes of assembly product and system product and then integrates the total cost values, has been designed. (2) A new method for estimating parameters of cross effects among R&D projects has been developed. (3) $ulcorner$Cross Effects Estimation Model$lrcorner$ to estimate multi-effects and cross effects by completion time among several projects has been designed. (4) $ulcorner$Integration Estimation Indicator$lrcorner$ for setting priority on a project group has been extracted by combination of total cost value and total effect value.

Net Ecosystem Productivity Determined by Continuous Measurement Using Automatic Sliding Canopy Chamber

  • Kim, Gun-Yeob;Lee, Seul-Bi;Lee, Jong-Sik;Choi, Eun-Jung
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.6
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    • pp.1179-1186
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    • 2012
  • For better understanding of carbon cycle dynamics of an agro-ecosystem, an accurate assessment of seasonal and daily $CO_2$ flux is essential to understand the relationship between various environmental factors and crop productivity. We developed the automatic sliding canopy chamber (ASCC) system that measured continuous net ecosystem productivity (NEP) over whole growing season under the natural meteorological rhythm. The ASCC was composed of two main parts which were sliding part for measuring NEP, and automatic opening and closing chamber (AOCC) for measuring soil respiration (SR) on the soil surface. The ASCC was developed by using open flow method for measuring soil $CO_2$ efflux. The disturbance of natural meteorological condition was minimized by opening the base frames. In the field test with barley (Hordeum vulgare L.), NEP was calculated at $140mg\;CO_2\;m^{-2}h^{-1}$ on a clear day using continuous data and eliminated the possibility of overestimate about 16% using one hour data during the day time. Unlike other small scale chamber system, installation on cropping-field made it possible to take any modifications which might be caused by natural environmental condition.

A Study on Helicopter Trajectory Tracking Control using Neural Networks (신경회로망을 이용한 헬리콥터 궤적추종제어 연구)

  • Kim, Yeong Il;Lee, Sang Cheol;Kim, Byeong Su
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.31 no.3
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    • pp.50-57
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    • 2003
  • In the paper, the design and evaluation of a helicopter trajectory tracking controller are presented. The control algorithm is implemented using the feedback linearization technique and the two time-scale separation architecture. In addition, and on-line adaptive architecture that employs a neural network compensating the model inversion error caused by the deficiency of full knowledge of helicopter dynamic is applied to augment the attitude control system. Trajectory tracking performance of the control system in evaluated using modified TMAN simulation program representing as Apache helicopter. It is show that the on-line neural network in an adaptive control architecture is very effective in dealing with the performance depreciation problem of the trajectory tracking control caused by insufficient information of dynamics.

Effectiveness of a Yeonkyopaedok-san Extract in the Treatment of The Common Cold : Results of a Community-based, Double Blind, Randomized Placebo Controlled Trial (감기에 대한 연교패독산의 유효성 평가를 위한 community-based 이중맹검 위약 대조군 연구)

  • Bae, Han-Ho;Kang, Wee-Chang;Park, Yang-Chun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.1
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    • pp.234-245
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    • 2008
  • Yeonkyopaedok-san(YPS) extract is widely used to treat the common cold. The purpose of this study was to evaluate the efficacy of YPS on the common cold. Two hundred Patients with common colds of recent onset were randomized to the double blind, placebo-controlled study. They received 800 mg YPS extract or placebo in capsules, orally dissolved 3 times a day for 7 days. The total symptom score was assessed by the physician, using a 5-point scale on start and finish. Resolution of cold symptoms based on subjective daily symptoms. Total symptom score was significantly decreased in YPS groups in comparison to that in placebo group (p=0.027). Headache (p=0.012), loss of appetite (p=0.037), eyeball discomfort (p=0.002) were more affected. Time to resolution of cold symptoms did not show significant effect (p=0.592). Adverse effects were less in the YPS group than placebo group (2% vs 3%). In this community-based, randomized controlled trial, YPS were effective in treating cold symptoms in college students.

A Comparative Study of Emotion Using the International Affective Picture System (국제정서사진체계를 사용하여 유발된 정서의 측정: 비교문화적 타당성 연구)

  • 이경화;김지은;이임갑;손진훈
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 1997.11a
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    • pp.220-223
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    • 1997
  • The International Affective Picture System (IAPS) developed by Lang and colleagues[1] is widely used in studies relating a variety of physiological indices to subjective emotions. In this study we investigated whether the IAPS can be used for Koreans without significant cultural biases in their subjective emotional reactions. Thirty IAPS picture slides were presented to a group of 52 college students and different 30 slides with similar 3 dimensional emotion ratings to another group of 42 students. Fof each slieds with exposal time of 8sec, subjects were asked to rate on the Semantic Differential Scale (SDS) and Self-Assessment Manikin (SAM) in the 3 dimensions of pleasure valence, arousal, and domensions of pleasure valence, arousal, and dominance. Fnctor analysis was done for SDS ratings, and correlations of SDS and SAM were calculated. Eighteen bipolar adjective were grouped into 3 dimensions of pleasure, arousal, dominance showing good agreement with previous study. SAM were calculated. Eighteen bipolar adjectives were grouped into 3 dimensions of pleasure, arousal, dominance showing good agreement with the previous study. SAM ratings were highly corrlated with two of the 6 SDS adjective pairs associated with the pleasure and dominance dimensions, but not with those associated with arousal dimension suggerting some cultural differences.

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Cutaneous melanoma (피부흑색종)

  • Lee, Seok-Jong;Lee, Soo Jung
    • Journal of the Korean Medical Association
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    • v.61 no.11
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    • pp.662-669
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    • 2018
  • The cutaneous melanoma has been regarded as rare disease entity in Korea for long time but it shows a silent growth recently. Furthermore the management of cutaneous melanoma including staging system, surgical principle, sentinel lymph node biopsy and subsequent complete node dissection and, most importantly, immunotherapy and target therapy against cutaneous melanoma recently. The incidence of cutaneous melanoma is steadily increasing in Korea but its increase is rapid recent 2 decades to 4.3 times and should be greater soon according to the steeper increase of life expectancy. New staging system proposed by American Joint Committee on Cancer (2017) includes changes in individual TNM category and stage groups, particularly from a prognostic viewpoint. Dermoscopy has been successfully introduced in the differential diagnosis of pigmented skin lesion focusing on cutaneous melanoma by non-invasive simple diagnostic tool. Sentinel lymph node biopsy was a issue of long debate whether survival benefit is real or not. Temporary conclusion about this question is reached after two large scale studies and immediate complete node dissection should be performed in a certain situations. Most important change is drug therapy focusing on immunotherapy and target therapy. Braf- and MEK-inhibitor, immune checkpoint inhibitor and PD-1 blocker has been proved to be effective as a sole or combination regimen against advanced and/or high-risk adjuvant setting of cutaneous melanoma. In conclusion, these remarkable changes will be reviewed shortly here.

Economies of Scale and Scope in the Korean Railway Industry: A Generalized Translog Cost Function Approach (일반초월대수 비용함수모형을 이용한 한국 철도산업의 규모 및 범위의 경제성 분석)

  • Park, Jin-Kyung;Kim, Sung-Soo
    • Journal of Korean Society of Transportation
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    • v.22 no.6
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    • pp.159-173
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    • 2004
  • Using a generalized translog multiproduct cost function model, this paper examines economies of scale and scope in the vertically-integrated Korean railway industry. The paper then conceptualizes that the Korea National Railroad (KNR) produces four outputs (passenger-kilometers, ton-kilometers of freight, average length of passenger trips, and average length of freight haul) using three input factors(labor, fuel and maintenance, and rolling stock and capital). Using time series data collected from the KNR's annual records for the years from 1977 to 2002, the simultaneous equation system consisting of a cost function and two input share equatins is estimated with the Zellner's iterative seemingly unrelated regression. The findings show that the cost function corresponding to a non-Cobb-Douglas, non-homothetic, and non-homogeneous production technology adequately represents the KNR's cost structure. On the other hand, the Korean railway industry experiences sizeable overall scale economies, which result from substantial product-specific scale economies associated with passenger-kilometers and freight ton-kilometers and from scope economies associated with their joint production. In addition, the magnitude of economies of scope is influenced largely by the ratio of passenger trips, and has increased over time as the former has increased while the latter has decreased.

Three Body Problem and Formation of Binary System (3체 문제와 연성계의 형성)

  • Jae Woo Park;Kyu Hong Choi;Kyong Chol Chou
    • Journal of Astronomy and Space Sciences
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    • v.2 no.1
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    • pp.19-33
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    • 1985
  • The singularities of differential Newtonian equation of motion in three body problem cause the loss of accuracy and the considerable increase of the computer time. These singularities could be eliminated during the process of regularization to transform the independent variables and the coordinate of Newtonian equations of motion. In this study, we calculated the positions and velocities of three body along the time scale to find out the unique solution of regularized Newtonian equations of motion with the $5^{th}$ order Runge-Kutta method by assuming the suitable initial velocities and positions. As the results of these calculations it is shown that the tripe stellar system eventually distintegrated, two of them formed a binary, and the last one escaped from this system with a hyperbolic orbit. This may suggest one possible explanation for the binary formation.

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Design of Improved UI of Automatic Parking Management System using License Plate Recognition (번호판 인식을 통한 자동 주차관리 시스템의 개선된 UI 설계)

  • Kim, Bong-Gi
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.2
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    • pp.1083-1088
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    • 2014
  • Recently, due to advances in both imaging technology and ICT, various types of image processing services became available and the application services of these two technologies are diversifying. Recognition of vehicle license plates is used in places where vehicle information is needed such as in parking management. However, existing systems have economic disadvantages like issuing parking tickets and attaching unnecessary equipment. In order to solve these problems, we designed and implemented automatic parking management system through recognition of vehicle license plates by using emguCV that is based on OpenCV. Additionally, we designed improved UI to handle the entire parking management situation which include information such as details of each parking vehicle, parking time and remaining parking spaces without screen movement. This improved UI is implemented with the use of WPF which is the latest technology in user program development. The emguCV used in this paper showed the most optimized performance in Intel based environment. With it, we obtained the result of within 0.5 seconds of recognition processing time and over 90% of recognition rate. Through improved UI, the manager could both simply and intuitively manage the entire system.

A Simple Ensemble Prediction System for Wind Power Forecasting - Evaluation by Typhoon Bolaven Case - (풍력예보를 위한 단순 앙상블예측시스템 - 태풍 볼라벤 사례를 통한 평가 -)

  • Kim, Jin-Young;Kim, Hyun-Goo;Kang, Yong-Heack;Yun, Chang-Yeol;Kim, Ji-Young;Lee, Jun-Shin
    • Journal of the Korean Solar Energy Society
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    • v.36 no.1
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    • pp.27-37
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    • 2016
  • A simple but practical Ensemble Prediction System(EPS) for wind power forecasting was developed and evaluated using the measurement of the offshore meteorological tower, HeMOSU-1(Herald of Meteorological and Oceanographic Special Unite-1) installed at the Southwest Offshore in South Korea. The EPS developed by the Korea Institute of Energy Research is based on a simple ensemble mean of two Numerical Weather Prediction(NWP) models, WRF-NMM and WRF-ARW. In addition, the Kalman Filter is applied for real-time quality improvement of wind ensembles. All forecasts with EPS were analyzed in comparison with the HeMOSU-1 measurements at 97 m above sea level during Typhoon Bolaven episode in August 2012. The results indicate that EPS was in the best agreement with the in-situ measurement regarding (peak) wind speed and cut-out speed incidence. The RMSE of wind speed was 1.44 m/s while the incidence time lag of cut-out wind speed was 0 hour, which means that the EPS properly predicted a development and its movement. The duration of cut-out wind speed period by the EPS was also acceptable. This study is anticipated to provide a useful quantitative guide and information for a large-scale offshore wind farm operation in the decision making of wind turbine control especially during a typhoon episode.