• 제목/요약/키워드: Weighted Average Model

검색결과 226건 처리시간 0.025초

NEWFM 기반 가중평균 역퍼지화에 의한 비선형 시계열 예측 모델링 (Nonlinear Time Series Prediction Modeling by Weighted Average Defuzzification Based on NEWFM)

  • 채수한;임준식
    • 한국지능시스템학회논문지
    • /
    • 제17권4호
    • /
    • pp.563-568
    • /
    • 2007
  • 본 논문은 가중 퍼지소속함수 기반 신경망(Neural Network with Weighted Fuzzy Membership Functions, NEWFM)을 이용하여 클래스의 분류강도를 구하고 비선형 시계열 추이선을 예측하는 방안을 제안하고 있다. NEWFM에 의하여 추출된 가중퍼지 소속함수(BSWFM)를 이용하여 입력값에 대한 분류강도를 구하게 되고, 이들에 대한 가중평균 역퍼지화를 통하여 비선형 시계열 추이선을 작성한다. 실증분석결과 NEWFM은 목표 클래스로 설정된 GDP에 대하여 92.22%의 분류성능을 보여 주었다. 따라서 동 비선형 시계열 추이선은 대표적인 경기지표인 GDP 추이에 비교적 높은 유사도를 나타내는 가운데 분석대상기간인 제5순환기-제8순환기 중 정점(peak)에서 평균 12개월, 저점(trough)에서 평균 6개월의 선행성(look-ahead)을 보여 줌으로써 경기변동에 앞서 상당기간의 시차를 둔 예측지표로서 활용가능성이 입증되었다. NEWFM은 그 특징선택(feature selection)에 의하여 선행지표 10개 중 3개의 축소를 기할 수 있게 해 줌으로써 보다 적은 수의 경제지표를 가지고도 분류성능을 90.0%에서 92.22%로 향상을 기하는 가운데 효율적인 예측기능을 수행할 수 있음이 입증되었다.

우리나라 산업보건관리(産業保健管理) 평가기준(評價基準)과 실태(實態)에 관(關)한 연구(硏究) (A Study on Occupational Health Program and Development of Evaluating Criteria for Occupational Health)

  • 이영수;문영한;김영기;정호근
    • Journal of Preventive Medicine and Public Health
    • /
    • 제11권1호
    • /
    • pp.98-109
    • /
    • 1978
  • The study was carried out for 101 establishments in Kyong-In areas to evaluate the industrial health management status utilizing the scoring method by Webb's model during the period from 1 September to October 30, 1977. To compare the results, reevaluation was made with the 45 questions' model prepared by 6 Korean professionals who were specialized in industrial health fields. The results were as follows: 1. The mean rate of affirmative answers for 101 establishments was 51.6%. The mean weighted score rate of affirmative answers was 52.3%. 2. The mean rate of affirmative answers on components of the philosophy and facility resource for 101 establishments was higher than that of average rate. The mean rate of affirmative answers on components of the health evaluation and health management among the health service program was lower than that of average rate. 3. The mean rate of affirmative answers on components was highter among the establishments with more than 500 employees. The mean rate of affirmative answers of chemical establishment was lower than that of others. 4. The mean rate of affirmative answers on 45 questions' model for 101 establishments were 67.1%. The mean weighted score rate of affirmative answers was 70.0%. 5. In case of 45 questions' model, the mean rate of affirmative answers on components of philosophy and treatment was higher than that of average rate and the mean rate of affirmative answers on components of the facility resource and the health evaluation was lower than that of average rate. 6. The mean rate of affirmative answers of the 45 Questions' model was higher than that of Webb's model in size and class of 101 establishments. Author concluded that Webb's model must be suitable for evaluating higher conditions of occupational health management than is presently used in Korean establishments. According to the results, however, there were no significant differences between Webb's model and the 45 questions' model. So it could be used to evaluate Occupational Health Program. For this objective, in Korean occupational situations, further study also must be made comprehensively thereafter.

  • PDF

SWAT 모형의 유출해석모듈 개선이 수질모의에 미치는 영향 (Effect of Improved Runoff Module in SWAT on Water Quality Simulation)

  • 김남원;신아현;이정우
    • 한국수자원학회논문집
    • /
    • 제42권4호
    • /
    • pp.297-307
    • /
    • 2009
  • 신뢰도 높은 수질 모의를 위해서는 유역 내 정확한 유출 모의가 반드시 선행되어야 한다. 본 연구에서는 연속방정식과 운동파 근사에 의한 Manning의 식이 결합된 비선형 저류방정식에 근거한 하도추적법과 금일 강수량을 고려하여 시간적으로 가중 평균된 유출곡선지수를 산정하도록 개선된 지표유출계산 모듈이 수질 모의에 미치는 영향을 분석하였다. 이를 대표적 준분포형 모형인 SWAT에 탑재하여 충주댐 유역에 적용하여 각 개선모듈별 독립적인 분석과 전체 개선의 효과를 개선 전 후로 분석하였다. 각 개선 모듈별 수질 모의의 기여도를 분석한 결과 지표유출계산 모듈의 개선보다는 하도추적의 개선이 더 많은 영향을 미치는 것으로 분석되었다. 이는 비점오염원의 특성 상 하도추적의 개선으로 인한 유출 지체 현상의 개선이 부하량의 배출에 가장 큰 요인으로 작용하였기 때문이라고 판단된다.

칼만 게인 궤환 평균을 이용한 적응 EWMA 관리도 설계 (A Study on the Design of Adaptive EWMA Control Chart using Kalman Gain Recursive Average)

  • 윤상원;윤석환;신용백
    • 품질경영학회지
    • /
    • 제24권1호
    • /
    • pp.73-86
    • /
    • 1996
  • Adaptive EWMA(Exponentially Weighted Moving Average)-x control chart using the Kalman gain recursive average is designed. The designed control chart is effective to on-line process monitoring as continuous flow processes. Performance evaluation between the designed control chart and traditional one is implemented. For this, ARL(Average Run Length) is adopted as a criterion. Results show that the designed adaptive EWMA-x control chart has shorter ARL than EWMA-x control chart when process mean is shifted. This model can be extended to process prevention control. The methodology proposed in this research is turned out to show the high performance than that of the given methodologies.

  • PDF

교통량 가중평균 방법을 적용한 COSMOS 속도 추정 (Speed Estimation by Applying Volume Weighted Average Methods in COSMOS)

  • 이상수;이승환;오영태;송성주
    • 한국ITS학회 논문지
    • /
    • 제2권1호
    • /
    • pp.63-73
    • /
    • 2003
  • 국내에서 사용되는 실시간 신호제어시스템은 각 차로별로 계산된 지점속도를 산술평균 모형을 적용하여 접근로의 속도로 추정하고, 이를 대기길이 추정 모형 과정에 중요 변수로 사용한다. 본 연구에서는 현재의 산술모형의 적정성을 검토하고 하나의 대안으로서 교통량 가중평균 모형을 제시하였다. 그리고 교통량 가중평균 모형과평균 개별차랑 지점속도의 이론적 관계를 해석하고, 이를 관계식으로 표현하였다. 제시된 관계식으로부터, 가중평균 모형은 각 차로의 교통량 이용비율과 평균속도 차이에 따라 산술평균과 선형적인 차이를 갖는 것을 파악하였다. 두 가지 모형에 대한 평가를 위하여 실시간 신호제어시스템으로 운영되는 한 개 교차로로부터 자료를 수집하여 각각 적용하였다. 분석 결과, 가중평균 모형이 현재의 산술평균 모형보다 현장 상황을 합리적이고 안정적으로 나타내는 대기 행렬 추정값을 제시하였다. 따라서 가중평균 모형을 실제 운영에 적용하는 것이 실시간 신호제어시스템의 기능적 안정성에 도움을 줄 수 있다고 판단된다.

  • PDF

Topic Extraction and Classification Method Based on Comment Sets

  • Tan, Xiaodong
    • Journal of Information Processing Systems
    • /
    • 제16권2호
    • /
    • pp.329-342
    • /
    • 2020
  • In recent years, emotional text classification is one of the essential research contents in the field of natural language processing. It has been widely used in the sentiment analysis of commodities like hotels, and other commentary corpus. This paper proposes an improved W-LDA (weighted latent Dirichlet allocation) topic model to improve the shortcomings of traditional LDA topic models. In the process of the topic of word sampling and its word distribution expectation calculation of the Gibbs of the W-LDA topic model. An average weighted value is adopted to avoid topic-related words from being submerged by high-frequency words, to improve the distinction of the topic. It further integrates the highest classification of the algorithm of support vector machine based on the extracted high-quality document-topic distribution and topic-word vectors. Finally, an efficient integration method is constructed for the analysis and extraction of emotional words, topic distribution calculations, and sentiment classification. Through tests on real teaching evaluation data and test set of public comment set, the results show that the method proposed in the paper has distinct advantages compared with other two typical algorithms in terms of subject differentiation, classification precision, and F1-measure.

가중평균 러셀(Russell) 방향거리함수모형을 이용한 은행산업의 비효율성 분석 (Analysis of influencing on Inefficiencies of Korean Banking Industry using Weighted Russell Directional Distance Model)

  • 양동현;장영재
    • 디지털융복합연구
    • /
    • 제17권5호
    • /
    • pp.117-125
    • /
    • 2019
  • 본 연구는 부실채권을 산출요소에 포함시켜 2004년부터 2013년까지 금융위기 전후 10년간 자료를 이용하여 가중평균 러셀 방향거리함수 모형(Weighted Rusell Directional Distance Model: WRDDM)에 의해 은행산업의 비효율성을 측정하였다. 그리고 이를 기초로 투입산출요소의 비효율성 기여효과를 산출하였으며 이 중 비정상적 유해산출물인 부실채권의 영향이 가장 큼을 실증하였다. 분석결과, 은행산업의 비효율성은 연평균 0.3912이며 이 중 무수익여신이 0.1883, 산출요소 0.098, 투입요소는 0.098 순으로 무수익여신의 비중이 가장 컸으며 금융위기 전 비효율성은 0.2995에서 금융위기 후 0.4829로 크게 증가하였는데 이는 부실책권의 비효율성이 금융위기 전 0.1088에서 금융위기 후 0.2678로 크게 증가한데 기인하였다. 결론적으로 투입산출 요소 중에서 인력, 총수신액, 투자증권 보다 부실채권인 무수익여신이 은행산업의 비효율성에 가장 중요한 영향을 미치고 있었으며 이에 은행산업의 기술적 효율성 측정시 정상 산출물 뿐만 아니라 비정상적인 유해산출물을 함께 고려하여야 함을 실증적으로 제시하였다. 그러나 본 연구는 은행의 효율성에 영향을 미치는 금융환경요인을 가중평균 러셀 방향거리함수모형에 통제하지 못한 한계점이 있다.

A Combined Process Control Procedure by Monitoring and Repeated Adjustment

  • Park, Changsoon
    • Communications for Statistical Applications and Methods
    • /
    • 제7권3호
    • /
    • pp.773-788
    • /
    • 2000
  • Statistical process control (SPC) and engineering process control (EPC) are based on different strategies for processes quality improvement. SPC reduces process variability by detecting and eliminating special causes of process variation. while EPC reduces process variability by adjusting compensatory variables to keep the quality variable close to target. Recently there has been needs for a process control proceduce which combines the tow strategies. This paper considers a combined scheme which simultaneously applies SPC and EPC techniques to reduce the variation of a process. The process model under consideration is an integrated moving average(IMA) process with a step shift. The EPC part of the scheme adjusts the process back to target at every fixed monitoring intervals, which is referred to a repeated adjustment scheme. The SPC part of the scheme uses an exponentially weighted moving average(EWMA) of observed deviation from target to detect special causes. A Markov chain model is developed to relate the scheme's expected cost per unit time to the design parameters of he combined control scheme. The expected cost per unit time is composed of off-target cost, adjustment cost, monitoring cost, and false alarm cost.

  • PDF

Assessment of Personal Exposure to Nitrogen Dioxide in Primary Schoolchildren

  • Cho Yong-Sung;Lee Jong-Tae;Kim Yoon-Shin
    • 한국환경보건학회지
    • /
    • 제32권3호
    • /
    • pp.207-214
    • /
    • 2006
  • This study was designed to assess the level of nitrogen dioxide from several microenvironments including inside the home, outdoors near the home, inside the school, outdoors near the school, and on the road for 42 primary schoolchildren during the month of December 2002 in Seoul, Korea. The average personal, indoor, outdoor $NO_2$ levels, and indoor/outdoor ratio were 45.08 ppb, 27.89 ppb, 30.96 ppb, and 0.89, respectively. The indoor $NO_2$ concentrations were significantly associated with the presence of a smoker with a gas stove. The estimated personal $NO_2$ exposure using time-weighted average equation of $34.64{\pm}5.29$ ppb was significantly lower than the measured personal exposure of $45.08{\pm}5.50$ ppb. Our results indicate that indoor $NO_2$ levels were associated with the presence of a smoker and a gas stove. Moreover, personal $NO_2$ exposure with a gas stove in the house was significantly higher than those without a gas stove.

Effects of DEM Resolution on Hydrological Simulation in, BASINS-BSPF Modeling

  • Jeon, Ji-Hong;Ham, Jong-Hwa;Chun G. Yoon;Kim, Seong-Joon
    • 한국농공학회지
    • /
    • 제44권7호
    • /
    • pp.25-35
    • /
    • 2002
  • In this study, the effect of DEM (Digital Elevation Model) resolution (15m, 30m, 50m, 70m, 100m, 200m, 300m) on the hydrological simulation was examined using the BASINS (Better Assessment Science Integrating point and Nonpoint Source) for the Heukcheon watershed (303.3 ㎢) data from 1998 to 1999. Generally, as the cell size of DEM increased, topographical changes were observed as the original range of elevation decreased. The processing time of watershed delineation and river network needed more time and effort on smaller cell size of DEM. The larger DEM demonstrated had some errors in the junction of river network which might affect on the simulation of water quantity and quality. The area weighted average watershed slope became milder but the length weighted average channel slope became steeper as the DEM size increased. DEM resolution affected substantially on the topographical parameter but less on the hydrological simulation. Considering processing time and accuracy on hydrological simulation, DEM grid size of 100m is recommended for this range of watershed size.