• 제목/요약/키워드: Representative Term

Search Result 439, Processing Time 0.028 seconds

Representative Temperature Assessment for Improvement of Short-Term Load Forecasting Accuracy (단기 전력수요예측 정확도 개선을 위한 대표기온 산정방안)

  • Lim, Jong-Hun;Kim, Si-Yeon;Park, Jeong-Do;Song, Kyung-Bin
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.27 no.6
    • /
    • pp.39-43
    • /
    • 2013
  • The current representative temperature selection method with five cities cannot reflect the sufficient regional climate characteristics. In this paper, the new representative temperature selection method is proposed with the consideration of eight representative cities. The proposed method considered the recent trend of power sales, the climate characteristics and population distribution to improve the accuracy of short-term load forecasting. Case study results for the accuracy of short-term load forecasting are compared for the traditional temperature weights of five cities and the proposed temperature weights of eight cities. The simulation results show that the proposed method provides more accurate results than the traditional method.

Automatic Generation of the Local Level Knowledge Structure of a Single Document Using Clustering Methods (클러스터링 기법을 이용한 개별문서의 지식구조 자동 생성에 관한 연구)

  • Han, Seung-Hee;Chung, Young-Mee
    • Journal of the Korean Society for information Management
    • /
    • v.21 no.3
    • /
    • pp.251-267
    • /
    • 2004
  • The purpose of this study is to generate the local level knowledge structure of a single document, similar to end-of-the-book indexes and table of contents of printed material through the use of term clustering and cluster representative term selection. Furthermore, it aims to analyze the functionalities of the knowledge structure. and to confirm the applicability of these methods in user-friend1y information services. The results of the term clustering experiment showed that the performance of the Ward's method was superior to that of the fuzzy K -means clustering method. In the cluster representative term selection experiment, using the highest passage frequency term as the representative yielded the best performance. Finally, the result of user task-based functionality tests illustrate that the automatically generated knowledge structure in this study functions similarly to the local level knowledge structure presented In printed material.

A Study on Sampling Techniques to Assure the Representativeness of Short-term Equivalent Noise Level (단기간 소음도의 대표성 확보를 위한 소음도 추출기법 연구)

  • Ryu, Hun Jae;Ko, Joon Hee;Chang, Seo Il;Lee, Byung Chan
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.22 no.12
    • /
    • pp.1213-1219
    • /
    • 2012
  • The purpose of this study is to present a guideline to design a short-term manual measurement of environmental noise level, which is more economical and flexible, but less representative than long-term automatic measurement. The proposed guideline can provide the number of measurement times and the length of measurement term required to secure the extent of the representativeness. The data was collected at 4 sites located in Seoul and at 4 sites located outside of Seoul. The probabilities for five-minute equivalent noise levels, Leq, 5min, to stay in an error range from the quarterly representative noise level were used to evaluate sampling techniques. The probability analysis of the daytime period showed that the noise levels measured between 10 am and 2 pm and between 9 pm and 10 pm have the probabilities higher than 60 %. On the other hand, even for the same length of total measurement time, increasing the number of random samplings results in higher probabilities than increasing the length of measurement term.

Monitoring and Long-term Trend of Total Column Ozone from Dobson Spectrophotometer in Seoul (1985~2017) (돕슨 분광광도계를 이용한 서울 상공의 오존층 감시 및 장기변화 경향(1985~2017))

  • Park, Sang Seo;Cho, Hi Ku;Koo, Ja-Ho;Lim, Hyunkwang;Lee, Hana;Kim, Jhoon;Lee, Yun Gon
    • Atmosphere
    • /
    • v.29 no.1
    • /
    • pp.13-20
    • /
    • 2019
  • Since 1985, the Dobson Spectrophotometer has been operated at Yonsei University, and this instrument has monitored the daily representative total ozone in Seoul. Climatological value for total ozone in Seoul is updated by using the daily representative observation data from 1985 to 2017. After updating the daily representative total ozone data, seasonal and inter-annual variation of total ozone in Seoul is also estimated after calculating inter-comparison between ground (Dobson Spectrophotometer) and satellite [Total Ozone Mapping Spectrometer (TOMS) and Ozone Monitoring Instrument (OMI)] observations. The global average of total ozone measured by satellite is 297 DU, and its recent amount is about 3.5% lower than the global amount in 1980s. In Seoul, daily representative total ozone is ranged from 225 DU to 518 DU with longterm mean value of 324.3 DU. In addition, monthly mean total ozone is estimated from 290 DU (October) to 362 DU (March), and yearly average of total ozone have been continuously increased since 1985. For the long-term trend of total ozone in Seoul, this study is considered the seasonal variation, Solar Cycle, and Quasi-Biennial Oscillation. In addition to the natural oscillation effect, this study also considered to the long-term variation of sudden increase of total ozone due to the secondary ozone peak. By considering these natural effects, the long-term total ozone trends from 1985 to 2017 are estimated to be 1.11~1.46%/decade.

Designing Hierarchical User Interface Model for Browsing the Knowledge Structure of a Single Document Using MDS (MDS를 이용한 개별문서의 계층적 지식구조 브라우징 인터페이스 설계)

  • Han, Seung-Hee;Lee, Jae-Yun
    • Journal of Information Management
    • /
    • v.35 no.3
    • /
    • pp.125-138
    • /
    • 2004
  • The purpose of this study is to propose a hierarchical user interfaces for browsing the knowledge structure of a single document. To generate the hierarchical knowledge structure, hierarchical term clustering and cluster representative term selection were performed with a single thesis in information science field, and the result was applied to design the interfaces which browse a single document hierarchically using multidimensional scaling. The interfaces can be applied to develop the user-friendly information retrieval system.

Study on the Effects of the Superficies-resolving Herbs based on Temperatures, Tastes and Effect Terms (기미(氣味)와 효능 용어를 활용한 해표약(解表藥)의 효능 고찰)

  • Yeon, Jihye;Song, Jichung;Jang, Heewon;Eom, Dongmyung
    • Journal of Korean Medical classics
    • /
    • v.30 no.4
    • /
    • pp.69-82
    • /
    • 2017
  • Objective : This study was conducted to infer the effect of superficies-resolveing herbs by analyzing effect terms which have extracted and refined, based on four temperatures and five tastes. Method : Firstly, temperatures, tastes and effect terms were extracted from the 27 kinds of superficies-resolving herbs written in Herbology. Then, each effect terms was divided into single meaning term and refined as typical term, using the inclusive effect terms I established. After that, herbs were grouped by tastes and found the effect terms which are mentioned most frequently. And it could be supposed to be classified into each herb's new effects based on the relationship between properties and those effect terms. It is also inferred into new tastes from some herbs by analysing the representative effects group of each taste and finding which other tastes can be related to each herb's effect. Result & Conclusion : All the superficies-resolving herbs can have wind-dispelling effect and superficies-resolving effect, except Bulpleuri Radix. This herb is able to has just the wind-dispelling effect. And it's more appropriate to categorize Bulpleuri Radix to heat-clearing herb group than superficies-resolving herb group, considering its several, distinctly cold characteristics. Some effects are concentrated to wind-cold-dispersing herb group and others to wind-heat-dispersing herb group. Each tastes has its own representative effect group. And, according to its tastes' representative effect, some of herbs are reasonable to get new effect term. With not so feasible reason, 4 kinds of herbs are supposed to contain all of hot, bitter, and sweet tastes. Also It's needed to study much deeper whether Perillae Herba, Zingiberis Rhizoma Crudus and Elsholtziae Herba are belong to superficies-resolving herb group or to interior-warming or damp-dissolving aromatic herb group.

Effects of Relational and Mandatory Influence Strategies on Sales Representatives and Headquarter Trust (관계적과 강제적 영향전략이 본사 신뢰에 미치는 영향 : 영업사원 신뢰의 매개역할)

  • Lee, Chang-Ju;Lee, Phil-Soo;Lee, Yong-Ki
    • Journal of Distribution Science
    • /
    • v.14 no.6
    • /
    • pp.53-63
    • /
    • 2016
  • Purpose - This study examines the effects of the influence strategies on sales representative and headquarter trust, and investigates how sales representative trust plays a mediating role in the relationship between influence strategies and headquarter trust. For these purposes, a structural model which consists of several constructs was developed. In this model, influence strategies that consist of relational influence strategies (information exchange, recommend, promise) and mandatory influence strategies (legal plea, request, threat) were proposed to affect the sales representative trust and in turn, increase the headquarter trust. Thus, this study proposed that sale representative trust plays a core mediating role in the relationship between relational and mandatory influence strategies and headquarter trust in B2B food materials distribution context. Research design, data, and methodology - For these purposes, the authors collected the data from 208 B2B specialized complex agents. We used the 2,200 B2B specialized complex agents which trade with CJ, Ottogi, and Daesang firms and supply food materials to restaurant, school cafeteria, supermarket and traditional market as a sample frame. Once we identified 330 B2B specialized complex agent owners, CEOs, and/or Directors who had agreed to participate in this study, we dropped off a questionnaire at each B2B specialized complex agent and explained the purpose of this study. The survey was conducted from October 1, 2015 to December 15, 2015. A total of 230 questionnaires were collected. Of these collected questionnaires, 28 questionnaires excluded since they had not been fully completed. The data were analyzed using frequency test, reliability test, measurement model analysis, and structural equation modeling with SPSS and SmartPLS 2. Results - First, information exchange, recommendation, and promise of relational influence strategies had positive effects on sales representative trust. The threat of mandatory influence strategies had a negative effect on sales representative trust, but legal plea and request did not have a significant effect on sales representative trust. Second, information exchange and recommendation of relational influence strategies had positive effects on headquarter trust, but promise did not. Also, legal plea, request, and threat of mandatory influence strategies did not have a significant effect on headquarter trust. Third, this findings show that sales representative trust plays a partial mediator between information exchange and headquarter trust, and threat and headquarter trust, and a full mediator between promise and headquarter trust, and recommendation and headquarter trust. Conclusions - The aim of this study was to examine the effects how diverse dimensions of relational and mandatory influence strategies relate to sales representative trust and headquarter trust. To do so, we integrated the influence strategies and the trust transfer theory to hypothesize that various influence strategies increase sales representative and headquarter trust. The findings of this study suggest that headquarter firms should establish and enforce proper influence strategies guidelines to make clear what proper actions sales representatives should implement in relationship with B2B specialized complex agents. Also, relational and mandatory influence strategies must be regarded as a long-term and ongoing strategy that eventually build a long-term orientation with B2B specialized complex agents and guarantee a company's sustainable growth and success.

Representative Keyword Extraction from Few Documents through Fuzzy Inference (퍼지 추론을 이용한 소수 문서의 대표 키워드 추출)

  • 노순억;김병만;허남철
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 2001.12a
    • /
    • pp.117-120
    • /
    • 2001
  • In this work, we propose a new method of extracting and weighting representative keywords(RKs) from a few documents that might interest a user. In order to extract RKs, we first extract candidate terms and then choose a number of terms called initial representative keywords (IRKS) from them through fuzzy inference. Then, by expanding and reweighting IRKS using term co-occurrence similarity, the final RKs are obtained. Performance of our approach is heavily influenced by effectiveness of selection method of IRKS so that we choose fuzzy inference because it is more effective in handling the uncertainty inherent in selecting representative keywords of documents. The problem addressed in this paper can be viewed as the one of calculating center of document vectors. So, to show the usefulness of our approach, we compare with two famous methods - Rocchio and Widrow-Hoff - on a number of documents collections. The results show that our approach outperforms the other approaches.

  • PDF

Statistical Analysis for Ozone Long-term Trend Stations in Seoul, Korea (통계적 기법을 적용한 서울의 오존 장기변동 대표측정소 선정)

  • Shin, Hyejung;Park, Jihoon;Son, Jungseok;Rho, Soona;Hong, Youdeong
    • Journal of Environmental Impact Assessment
    • /
    • v.24 no.2
    • /
    • pp.111-118
    • /
    • 2015
  • This study was conducted for the establishment of statistical method to determine the representative air quality monitoring station representing long-term ozone trends of Seoul. In this study, hourly ozone concentrations from 2002 to 2011 were used for further analysis. KZ-filter, correlation matrix, cluster analysis, and Kriging method were applied to select the representative station. The analysis based on correlation matrix found that long-term trend of ozone concentrations measured at Sinjung, Sadang, and Bun-dong showed a high correlation. The cluster analysis found that the former three stations belonged to the same cluster. The analysis based on Kriging method also showed that the former three stations were highly correlated with other stations in spatial distribution. Considering these results and the highest correlation coefficient of Sinjung station, the Sinjung station was the most suitable as the representative station used to understand the long-term ozone trend of Seoul. This result could be applied to understand long-term trend of other pollutants. Furthermore, this result can also be used to assess the appropriacy of spatial distribution of national air quality monitoring stations.