• Title/Summary/Keyword: h-지수

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Improving the Perfectionism Index to Identify Influential Journals versus Mass Producers (완벽주의 지수 PI의 개량을 통한 유력 학술지와 대량생산 학술지의 구분)

  • Lee, Jae Yun
    • Journal of the Korean Society for information Management
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    • v.36 no.2
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    • pp.201-222
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    • 2019
  • The Perfectionism Index (PI) is an indicator that is recently proposed to distinguish influential researchers from mass producers. In this study, Near Perfectionism Index (NPI), an improved indicator of Perfectionism Index, can be a solution to the problem of PI that indiscriminately gives a penalty to all low-cited papers regardless of publishing time or other issues. NPI improved the method to give a penalty to tail complement area considering the citation distribution curve. It prevents the improvement of the h-index from adversely affecting the researcher's influence indicator. This study uses NPI to evaluate information and library science journals in Web of Science database. It successfully distinguishes between influential journals and mass producers unlike journal h-index or average citation frequency which could not differentiate influentials from mass producers.

The Changes in the Quality of Life Measure of the Seoul Metropolitan Area (수도권 삶의 질 지수 변동에 관한 연구)

  • Lee, Se-Hyung;Chang, Hoon;Rho, Jin-A
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.29 no.1
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    • pp.29-37
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    • 2011
  • The purpose of this research is to measure Quality of Life indices using Factor Analysis and Principle Component Analysis and to analyze the spatial patterns of Quality of life distribution in the Seoul Metropolitan Area in terms of spatial association using spatial statistics and spatial exploratory technique. In order to check the degree of clustering, this study used spatial autocorrelation indices, global Moran's I index. In addition, local scale analysis was conducted using Moran Scatterplot and Local Moran's I to identify the spatial association pattern and the high Quality of life. The analysis based on global statics showed that, in the Seoul Metropolitan Area, QoL Indices had been distributed with positive spatial association. According to the local spatial statistics, the general tendency of clustering H-H clusters which were mainly concentrated on the Seoul, L-H clusters were concentrated on the Kyunggi-Do and L-L Clusters showed the regional extent of lagging behind. However, in case of H-H, L-H Clusters they had been spread out in the Newtown as population increase.

Improved methods for assessing single paper's citation impact (단일 문헌의 인용 영향력 측정 방식의 개선)

  • Lee, Jae Yun
    • Proceedings of the Korean Society for Information Management Conference
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    • 2011.08a
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    • pp.29-34
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    • 2011
  • 최근 인용 네트워크 분석을 통해서 단일 문헌의 인용 영향력을 측정하려는 시도가 다양하게 전개되고 있다. 널리 알려진 PageRank를 보완하려는 일부 시도와 함께 h-index를 단일 문헌의 인용 영향력 측정에 적용한 단일문헌 h-index도 제안되었다. 이 연구에서는 Web of Science에서 검색한 계량정보학 분야 문헌집합을 대상으로 여러 측정 방식의 특징을 비교해본 후, 새로운 인용지수 2종을 제안하였다. 제안한 인용지수는 PageRank처럼 전역 네트워크 분석 방식인 지수 1종과 h-index처럼 지역 네트워크 분석 방식인 지수 1종으로서 상황에 따라 선택하여 사용할 수 있다.

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Analysis of Circulation Measures based on Circulation Data of Colleges in a University (단과대학별 도서관 장서 활용 현황 분석을 위한 대출데이터 기반 대출지수 비교)

  • Choi, Sanghee;Lee, Jae Yun
    • Journal of the Korean Society for information Management
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    • v.35 no.4
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    • pp.125-140
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    • 2018
  • Circulation data is a key data set of academic libraries in terms of collection development and service improvement This study aims to identify the characteristics of circulation measures and their feasibility. This study collected the circulation data of 10 colleges in a university and analyzed 4 measures based on the circulation data: circulation frequency, circulation entropy, circulation h-index, and circulation divergence. These measures are to present the circulation topics of each college. This study identified that circulation entropy tends to present general topics which are popular for many colleges, but circulation divergence tends to present specific topics which are preferred by a specific college.

Comparative Study on Active Control Algorithms through Weighting Functions (가중함수에 따른 능동제어 알고리듬의 비교 연구)

  • Min, Kyung-Won;Kim, Jin-Koo;Kim, Sung-Choon;Chung, Lan
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.14 no.2
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    • pp.173-179
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    • 2001
  • 성능지수는 제어 대상이 되는 구조물의 응답과 제어기의 성능에 관한 가중함수로 구성되어 있다. 따라서 가중함수의 설계에 따라 성능지수가 변화되며 제어 효율이 달라진다. 본 논문에서는 최적 능동제어 알고리듬의 일종인 시간 영역에서의 성능지수를 고려한 LQR기법과 LQG기법 및 주파수 영역에서의 성능지수를 고려한 H₂기법에 대하여 동일한 가중함수를 적용하여 제어 성능인 제어율과 제어력을 비교하는데 목적을 두고 있다. 그러나, LQG기법은 모든 상태 변수를 알아야 하는 LQR기법의 한계를 극복할 수 있으며 LQR기법과 동일 수준의 제어율과 제어력을 보이고 있고 출력 제어라는 장점을 고려하면 현실적인 기법이라고 말할 수 있다. 마지막으로 구조물 응답과 제어기의 주파수 특성을 고려하여 주파수 필터의 가중함수를 설계하는 H₂기법을 분석하였다. H₂기법은 제어력을 저주파수 영역에 집중시킬 수 있기 때문에 구조물 응답을 효과적으로 제어할 수 있는 방법으로 분석되었다.

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The effect of fluoridation on discoloring of bleached teeth (불소 도포가 미백 처리된 치아의 색변화에 미치는 영향)

  • Jang, Hyang-Ah;Suh, Kyu-Won;Ryu, Jae-Jun
    • The Journal of Korean Academy of Prosthodontics
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    • v.47 no.3
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    • pp.257-265
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    • 2009
  • Statement of problem & Purpose: To study the effect of different fluoridation methods after in-office bleaching on the color of teeth during severe staining with coffee. Material and methods: 44 specimens were randomly divided into four groups. Group 1 (no bleaching, no fluoride, coffee) was served as control for the influence of coffee on the color of untreated teeth. Group 2, 3 and 4 were undergone bleaching with 35% $H_2O_2$ for 30 minutes a day on 3 consecutive days. Group 2 was remained without fluoridation. Group 3 and 4 were fluoridated for 1 hour with either Cavity shield$^{(R)}$ or pH 7 Gel$^{(R)}$. All of groups were immersed in coffee solution for 7 days. Color determination was accomplished using the spectrophotometer (VITA Easyshade$^{(R)}$). Results: ${\Delta}L$ and ${\Delta}h$ increased, whereas ${\Delta}C$ decreased in the bleached groups. Pairwise comparisons with Tukey's HSD showed that there were statistically significant differences for ${\Delta}L$ and ${\Delta}h$ between the bleached groups and the non-bleached group (P < .05). ${\Delta}L$ and ${\Delta}h$ decreased continuously, while ${\Delta}C$ showed an increase after a decrease in all of groups during immersion in coffee solution. After immersion in coffee solution for 7 days there were no statistically significant differences for ${\Delta}L$, ${\Delta}C$ and ${\Delta}h$ between the groups (P > .05). Also there were no statistically significant differences for ${\Delta}L$, ${\Delta}C$ and ${\Delta}h$ between the group 3 treated with Cavity shield. and the group 4 treated with pH 7 Gel. (P > .05). Conclusion: It was concluded that fluoridation was not beneficial to the prevention of extrinsic stains after bleaching.

The Characteristics of Curvature Ductility Factor of Reinforced Concrete Hollow Section Beams (철근콘크리트 속빈 단면 보의 곡률연성지수 특성)

  • Lee, Hyung-Joon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.12
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    • pp.6542-6549
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    • 2013
  • In highly elevated piers and long span beams, a hollow section is often used to reduce the self-weight and increase the flexural rigidity of members. Numerical analysis was conducted to obtain the moment-curvature curves and curvature ductility factor for the RC hollow section beams under a range of hollow portion sizes and reinforcement conditions in the upper flange and web. The curvature ductility factor was constantly maintained until the hollow portion size($b_i/b_o/h_i/h_o$) was less than or equal to 0.5. The curvature ductility factor decreased sharply if ($b_i/b_o/h_i/h_o$) was 0.7 or more. The curvature ductility factor of the beam decreased if reinforcement was provided in the web of the RC hollow section beam. To obtain the same level of the ductility factor as the singly reinforced section, the reinforcement should be provided in the upper flange as much as the web reinforcement.

백상폐지의 과산화수소 표백에 미치는 활성제의 영향

  • 안병준;백기현
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2001.04a
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    • pp.63-70
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    • 2001
  • Sodium persulfate, prestogen W, prestogen EB, citric acid 및 thiourea의 첨가에 따른 $H_2O_2$ 표백 효과가 연구되었다. Sodium persulfate(1%), Prestogen EB(15.0%)를 $H_2O_2$ 활성제로 첨가하여 표백할 경우 기존 $H_2O_2$ 표백(86.0% ISO)보다 표백 펄프의 백색도가 2-3% ISO 더 증가하였다. $H_2O_2$ 표백 후 thiourea를 첨가하여 표백하는 산화-환원 연속표백(87.9% ISO)에서도 $H_2O_2$ 표백 후 FAS로 2단 표백(88.3% ISO)을 한 경우와 비슷한 백색도를 나타내었다. 한편 표백 펄프의 인장지수, 파열지수 그리고 인열지수는 기존 표백 또는 Prestogen EB를 첨가할 경우 높고 sodium persulfate 첨가에서 가장 낮았다. 산화-환원 연속 표백된 펄프의 강도도 기존 $H_2O_2$ 표백보다 미세하게 낮았다.

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A Comparative Study on the Centrality Measures for Analyzing Research Collaboration Networks (공동연구 네트워크 분석을 위한 중심성 지수에 대한 비교 연구)

  • Lee, Jae Yun
    • Journal of the Korean Society for information Management
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    • v.31 no.3
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    • pp.153-179
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    • 2014
  • This study explores the characteristics of centrality measures for analyzing researchers' impact and structural positions in research collaboration networks. We investigate four binary network centrality measures (degree centrality, closeness centrality, betweenness centrality, and PageRank), and seven existing weighted network centrality measures (triangle betweenness centrality, mean association, weighted PageRank, collaboration h-index, collaboration hs-index, complex degree centrality, and c-index) for research collaboration networks. And we propose SSR, which is a new weighted centrality measure for collaboration networks. Using research collaboration data from three different research domains including architecture, library and information science, and marketing, the above twelve centrality measures are calculated and compared each other. Results indicate that the weighted network centrality measures are needed to consider collaboration strength as well as collaboration range in research collaboration networks. We also recommend that when considering both collaboration strength and range, it is appropriate to apply triangle betweenness centrality and SSR to investigate global centrality and local centrality in collaboration networks.

A Comparative Study of the Impacts among Patent Assignees in Pharmaceutical Research based on Bibliometric Analyses (계량서지학적 분석을 통한 약물연구분야 특허출원인 간 영향력 비교)

  • Kim, Heeyoung;Park, Ji-Hong
    • Journal of the Korean Society for information Management
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    • v.39 no.1
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    • pp.1-15
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    • 2022
  • This study analyzes the relationship of citations appearing in the patent data to understand knowledge transfers and impacts between patent documents in the field of pharmaceutical research. Patent data were collected from a website, Google Patents. The top 25 assignees were selected by searching for patent documents related to pharmaceutical research. We identify the citation relationships between assignees, then calculate and compare the values of h-index and derived indicators by using the number of citations and rank for each document of each assignee. As a result, in the case of pharmaceutical research, the assignee, such as 'Pfizer, MIT, and Abbott' shows a high impact. Among the five bibliometric indicators, the g-index and hS-index show similar results, and the indicators are the most related to the rankings of Total Citation Frequency, Cites per Patents, and Maximum Citation Frequency. In addition, it is highly related to the five indicators in the order of Total Citation Frequency, Cites per Patents, and Maximum Citation Frequency. In some cases, it is difficult to make an accurate comparison with Cites per Patents alone, which is previously known to indicate the technological influence of patent assignees.