• Title/Summary/Keyword: A-index

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Response of the Geomagnetic Activity Indices to the Solar Wind Parameters

  • Ahn, Byung-Ho;Park, Yoon-Kyung
    • Journal of Astronomy and Space Sciences
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    • v.25 no.2
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    • pp.129-138
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    • 2008
  • This study attempts to show how the geomagnetic indices, AU, AL and Dst, respond to the interplanetary parameters, more specifically, the solar wind electric field VBz during southward interplanetary magnetic field (IMF) period. The AU index does not seem to respond linearly to the variation of southward IMF. Only a noticeable correlation between the AU and VBz is shown during summer, when the ionospheric conductivity associated with the solar EUV radiation is high. It is highly likely that the effect of electric field on the eastward electrojet intensification is only noticeable whenever the ionospheric conductivity is significantly enhanced during summer. Thus, one should be very cautious in employing the AU as a convection index during other seasons. The AL index shows a significantly high correlation with VBz regardless of season. Considering that the auroral electrojet is the combined result of electric field and ionospheric conductivity, the intensification of these two quantities seems to occur concurrently during southward IMF period. This suggests that the AL index behaves more like a convection index rather than a substorm index as far as hourly mean AL index is concerned. Contrary to the AU index, the AL index does not register the maximum value during summer for a given level of VBz. It has something to do with the findings that discrete auroras are suppressed in sunlight hemisphere (Newell et al. 1996), thus reducing the ionospheric conductivity during summer. As expected, the Dst index tends to become more negative as VBz gets intensified. However, the Dst index (nT) is less than or equal to 15VBz(mV/m) + 50(Bz < 0). It indicates that VBz determines the lower limit of the storm size, while another factor(s), possibly substorm, seems to get further involved in intensifying storms. Although it has not been examined in this study, the duration of southward IMF would also be a factor to be considered in determining the size of a storm.

Calculation of Cronbach's Alpha Coefficient, Generalizability Index (GI), and Dependability Index (DI) in the Model Types of Survey Design (서베이 설계 모형별 Cronbach's Alpha 계수와 GI, DI 산출방안)

  • Choi, Sung-Woon
    • Proceedings of the Safety Management and Science Conference
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    • 2011.04a
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    • pp.701-705
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    • 2011
  • The paper reviews Cronbaha's coefficient to measure a single source of error. On the contrary to classical measurement theory, the generalizability study can be used in the social survey design to calculate Generalizability Index (GI) and Dependability Index (DI) for measuring multiple sources of errors of behavior evaluation. The study proposes application guidelines to implement R:($A{\times}B$) mixed models that are composed of random factor and fixed factor.

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Performance Index-Based Evaluation of Quadruped RoboticWalking Configuration

  • Kim, Byoung-Ho
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.10 no.4
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    • pp.308-313
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    • 2010
  • This paper presents a performance index-based evaluation for a better quadruped robotic walking configuration. For this purpose, we propose a balance-based performance index that enables to evaluate the walk configuration of quadruped robots in terms of balance. In order to show the effectiveness the proposed performance index, we consider some types of walking configurations for a quadruped robotic walking and analyze the trend of the proposed performance index in those quadrupedal walking. Through the simulation study, it is shown that an effective walk configuration for a quadrupedal walking can be planned by adopting the proposed performance index.

A Study on the Laser Measurement Experiment for Performance Advancement of Tilting Index Table (틸팅 인덱스 테이블의 성능 향상을 위한 레이저 측정 실험에 관한 연구)

  • Kim, Kwang-Sun;Lee, Tae-Ho;Lee, Choon-Man
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.5
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    • pp.26-30
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    • 2011
  • Currently, many researches are carried out about tilting index table, which is one of the main component of 5-axis machine tool. The performance of the tilting index table is associated the rotational accuracy which is very important factor for high precision machining because it have an effect on machining error. In this paper, a tilting index table is developed, and the rotational accuracy of the tilting index table using a laser measurement equipment is measured. In addition, a correction value is obtained from the measured value through compensation, and the correction value is used to improve the accuracy of the table. Comparative analysis is carried out for the accuracy of the table before and after compensation. This paper can be used by a reference for performance and reliability advancement of tilting index table.

색인사 연구

  • 박준식
    • Journal of Korean Library and Information Science Society
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    • v.2
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    • pp.23-59
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    • 1975
  • Indexes has not devcloped as an independent branch in library science from the beginning, but it has gradually evolved in a clo~eas sociation with catalog and under the direct influence of the development of publishing pro cesses and of the rapid social changes. Historically, index in the West can be traced back to eariler concordance. On the other hand, index in the Bast does not show a continuous development. It started with book catnlog, but other types of indexing were later 'adopted from the West. Indexing in the West and in the East can be summarized as follows: 1) In the West, Taylor considers Gesner's Pandectae was the first index but the Concordance of the Bible in 1247 was the first true index. Indexing method was first established later in 1545 in Gesner's Partitiones which appeared in three volumes. Classified index appeared after Partitions, but alphabetically ordered index was not developed until th eseventeenth century. The pxiodical index of La France S~auante in 1683 proved -its value, and Poole's An Alphabetical Index in the nineteenth century became the turning point in the development of indexing. After Poole's Index appeared periodical index and book catalog gradually began to be treated separately, and subject index and cross reference were incorporated into indexing. Also dictionary arrangement of the indexed items was adopted in the second half of the nincteenth, century after Charles A. Cutter developed his theory of rules for dictionary catalog and systematic studies of indexing were carried out by many scholars. In the twentieth century, index was mainly developed in the United States of America, especially by Wilson publishing Company. The general trend is to move away from the gcncral index to subject index. Also the ncwspapcr indcx such as The Times I~zdcx is 21 landmark in the history cf indcxing. 2) In China, thcs arc somc cvidcnccs that $Bizgluh(&), $ was the first indcx, but unforlunatcly the book itsclf has not been found as yet.

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Developing an Index of Usability to Evaluate Utilization of Mobile Toilets among the Elderly: A Case Study (고령자의 이동변기에 대한 사용성평가 지표 개발 : 사례 연구)

  • Kim, Seonchil;Lim, Hyunsub;Cho, Sunghyoun
    • Journal of The Korean Society of Integrative Medicine
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    • v.6 no.3
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    • pp.83-92
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    • 2018
  • Purpose : The purpose of this study was to develop an index of usability that reflects the needs and characteristics of the elderly. The usability index is used primarily to assess issues in the usability of a product. Methods : In this study, 22 items for mobile toilet usability index were developed by consulting with 12 elderly users, 6 caregivers, and 12 experts. The usability evaluation index was intended to increase reliability through preliminary and main evaluations. In addition, the validity of the items used as the usability evaluation index was verified to prove that the index is effective for the evaluation. Result : The usability index is a welfare tool developed by gathering data from various sources such as previous studies dealing with usability evaluation, characteristics of users, range of use, and environment of product use. Conclusion : The development of the usability index for mobile toilets was useful for the user to quantitatively derive the problem of the product. Consequently, user needs and usability problems can be identified, which can help improve product quality.

A Study on the Reliability Evaluation Index Development for the Information Resources Retained by Institutions: Focusing on Humanities Assets

  • Jeong, Dae-Keun;Noh, Younghee
    • International Journal of Knowledge Content Development & Technology
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    • v.9 no.2
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    • pp.65-89
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    • 2019
  • This study has the aim of developing an evaluation index that can help evaluate the reliability of the information resources of institutions retaining humanities assets for the purposes of laying out the foundation for providing one-stop portal service for humanities assets. To this end, the evaluation index was derived through the analysis of previous research, case studies, and interviews with experts, the derived evaluation index was then applied to the humanities assets retaining institutions to verify the utility. The institutional information resources' reliability evaluation index consisted of the two dimensions of the institutions' own reliability evaluation index. The institution provided a service and system evaluation index. The institutions' own reliability evaluation index consisted of 25 points for institutional authority, 25 points for data collection and construction, 30 points for data provision, and 20 points for appropriateness of data, for a total of 100 points, respectively. The institution provided service and system evaluation indexes consisting of 25 points for information quality, 15 points for appropriateness (decency), 15 points for accessibility, 20 points for tangibility, 15 points for form, and 10 points for cooperation, for the total of 100 points, respectively. The derived evaluation index was used to evaluate the utility of 6 institutions representing humanities assets through application. Consequently, the reliability of the information resources retained by the Research Information Service System (RISS) of the Korea Education & Research Information Service (KERIS) turned out to be the highest.

Drought Assessment with SPI and DRI in Uiryeong-Gun (SPI와 DRI를 활용한 의령군 지역의 가뭄 평가)

  • Kwak, Jesang;Kim, Gwangseob;Jung, Younghun;Um, Myoung-Jin
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.4
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    • pp.457-467
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    • 2022
  • Drought has strong local characteristics, an objective definition or standard that can define the progress or severity of drought is needed and to date, many drought-related studies are being conducted around the world. In this study, Standardized Precipitation Index (SPI), which is a representative meteorological drought index, was calculated, and the drought risk index (DRI) that can consider actual drought was applied to the target area, Uiryeong-gun, by applying the drought vulnerability index (DVI) and the drought hazard index (DHI). A method for practical drought evaluation that can establish a water supply system is presented in this study.

JONES' INDEX FOR FIXED POINT ALGEBRAS

  • Lee, Jung-Rye
    • Communications of the Korean Mathematical Society
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    • v.13 no.1
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    • pp.29-36
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    • 1998
  • We show that if M is a $II_1$-factor and a countable discrete group G acts outerly on M then Jones' index $[M:M^G]$ of a pair of $II_1^-factors is equal to the order $\mid$G$\mid$ of G. It is also shown that for a subgroup H of G Jones' index $[M^H:M^G]$ is equal to the group index [G:H] under certain conditions.

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Theory and practice of alphabetical subject indexing (주제색인의 이론과 실제)

  • 윤구호
    • Journal of Korean Library and Information Science Society
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    • v.10
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    • pp.95-131
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    • 1983
  • Index is a systematic guide to items contained in, or concepts derived from, a collection, Thus, it is represented as a paired set of index terms (t) and documents (D) : I= {(t,D) vertical bar t .mem. V, D .mem. W), where V is index vocabulary and W is document collection. Indexing is the process of analysing the informational content of records of knowledge and expressing the informational content in the language of the indexing system. It involves: 1) Selecting indexable concepts in a document; and 2) expressing these concepts in the language of the indexing system (as index entries): and an ordered list. Indexing process involves technical, semantic and syntactic problems. Technical problems are related to the accuracy of indexing, which is primarily governed by the indexer's ability of analysing subject, identifying indexable concepts, and coding. The proper levels of indexing exhaustivity, and index language specificity are also significant factors affecting the quality of index. Semantic problems are related to the choice of index terms and the form in which they should be used. Equivalent, hierarchical and affinitive/associative relationships of index terms are involved. Syntactic problems are largely related to the coordination of index terms. This process of coordination arises from the need to be able to search for the intersection of two or more classes defined by terms denoting distinct concepts. Finally, most valuable aspects of alphabetical subject indexing theories and practices are derived from those of Cutter, Kaiser, Ranganathan, Coates, Lynch and Austin, and discussed in details.

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