• 제목/요약/키워드: Ranking effect

검색결과 207건 처리시간 0.026초

하이퍼링크 구조를 이용한 웹 검색의 순위 알고리즘에 관한 연구 (The Study on the Ranking Algorithm of Web-based Sear ching Using Hyperlink Structure)

  • 김성희;오건택
    • 정보관리연구
    • /
    • 제37권2호
    • /
    • pp.33-50
    • /
    • 2006
  • 본 연구에서는 하이퍼 링크 구조를 이용한 웹 검색 알고리즘에 대해 살펴 본 후 페이지 품질을 측정하기 위해 웹의 하이퍼 구조를 이용하고 있는 알고리즘인 HITS와 PageRank를 분석하였다. 이어서 이들 방법을 이용한 검색 엔진인 Google과 Ask.com을 검색 알고리즘의 특성을 기준으로 분석하였다. 이런 연구는 미래의 웹 문서의 중요도를 평가하는 데 기초자료로 활용할 수 있으며, 웹 정보검색의 검색성능을 향상시키는 시스템 개발에 도움이 될 수 있을 것이라 생각한다.

4-(Nitrobenzyl)Pyridine에 의한 알킬화합물들의 잠재적 변이원성에 대한 구조활성 및 광화학효과의 연구 (Photosensitization Effect and Structure-Activity Relationship on Mutagenic Potential of Alkylating Agents by 4-(Nitrobenzyl)Pyridine (4-NBP) test)

  • 김재현;엄애선;류재천
    • 한국환경성돌연변이발암원학회지
    • /
    • 제21권1호
    • /
    • pp.23-29
    • /
    • 2001
  • The NBP assay was conducted to determine the photomutagenic or photocarcinogenic potential of alkylating agents. Using a 4-NBP in vitro technique, whereby photochemical treatment on CAS (Chemical Activation System) was performed to investigate the enhancement effect, 20 compounds were shown to undergo alkylating mechanisms with 4-NBP. Chemically meaningful results were obtained with different sets of 20 compounds for the alkylating activities due to the UV irradiation, demonstrating that all of the testing compounds showed increasing photoalkylating effects either in the presence or absence of CAS in comparison with previously reported data, except furoic acid and fumaric acid that showed decreasing effect in the presence of a CAS. Caffeine did not show a meaningful result either. However, these findings demonstrate the effects of potential photoalkylating activity in chemical activation system (CAS) and suggest a potential risk-ranking system for the in vivo assays.

  • PDF

시계열 군집분석을 통한 디지털 음원의 순위 변화 패턴 분류 (Derivation of Digital Music's Ranking Change Through Time Series Clustering)

  • 유인진;박도형
    • 지능정보연구
    • /
    • 제26권3호
    • /
    • pp.171-191
    • /
    • 2020
  • 본 연구는 현대 사회에서 가장 가치 있는 문화자산이자 한류의 흐름에서 특히 중요한 위치를 차지하는 디지털 음악에 초점을 두었다. 디지털 음악에 대하여 공신력 있는 음원 차트인 '가온 차트'에 진입한 음원들의 73주간 순위 변화를 수집하였으며 유사한 특징을 가지는 패턴들로 분류하였다. 이후 각 순위 변화 패턴으로부터 주목할 만한 특징에 대한 설명적 분석을 수행하였다. 구체적으로 음원에 대한 신뢰도 이슈가 발생하기 이전 기간의 국내 발매된 디지털 음원들로 한정하여 시점을 일치시킨 후 시계열 군집분석을 통해 패턴을 도출하고자 하였다. 데이터 수집과 전처리를 통하여 742건의 중복되지 않는 음원들을 확보하였고, 시계열 순위 변화에 대한 시계열 군집분석 결과 16개의 패턴들이 도출되었다. 이후 도출된 패턴들을 기반으로 '스테디셀러'와 '원 히트 원더'의 두 가지 유형의 대표적인 패턴을 확인하였다. 나아가 두 패턴에 대하여 차트 내에서 음원의 생존 기간과 음원 순위에 관점에서 다섯 가지의 세분화된 패턴으로 분류하였다. 각 패턴들이 가지는 중요한 특징들은 다음과 같다. 원 히트 원더형 패턴에서 아티스트의 슈퍼스타 효과와 편승효과가 강하게 나타났으며, 소비자들의 디지털 음원 선택에 강한 영향을 미친다는 것을 확인하였다. 나아가 스테디셀러형 패턴을 통해서 매우 오랜시간 소비자들의 선택을 받는 음원들을 확인하였고, 소비자의 니즈를 관통하며 가장 많은 선택을 받는 음원들이 오히려 원 히트 원더형 패턴이 아니라 스테디셀러: 중기 패턴에 포진하고 있음을 확인하였다. 특히 주목할 만한 점은 스테디셀러형 패턴을 통해 기존의 패턴과는 상반되는 '차트 역주행' 현상을 확인했다는 것이다. 본 연구는 디지털 음원을 중심으로 상대적으로 소외되었던 분야인 시간의 흐름에 따른 음원의 순위 변화에 초점을 두었고, 음원의 흥행과 순위를 예측하는 것이 아니라 순위 변화의 패턴을 세분화함으로써 음원 연구에 대한 새로운 접근을 시도하였다는 점에서 의의가 있다.

시맨틱 웹 자원의 랭킹을 위한 알고리즘: 클래스중심 접근방법 (A Ranking Algorithm for Semantic Web Resources: A Class-oriented Approach)

  • 노상규;박현정;박진수
    • Asia pacific journal of information systems
    • /
    • 제17권4호
    • /
    • pp.31-59
    • /
    • 2007
  • We frequently use search engines to find relevant information in the Web but still end up with too much information. In order to solve this problem of information overload, ranking algorithms have been applied to various domains. As more information will be available in the future, effectively and efficiently ranking search results will become more critical. In this paper, we propose a ranking algorithm for the Semantic Web resources, specifically RDF resources. Traditionally, the importance of a particular Web page is estimated based on the number of key words found in the page, which is subject to manipulation. In contrast, link analysis methods such as Google's PageRank capitalize on the information which is inherent in the link structure of the Web graph. PageRank considers a certain page highly important if it is referred to by many other pages. The degree of the importance also increases if the importance of the referring pages is high. Kleinberg's algorithm is another link-structure based ranking algorithm for Web pages. Unlike PageRank, Kleinberg's algorithm utilizes two kinds of scores: the authority score and the hub score. If a page has a high authority score, it is an authority on a given topic and many pages refer to it. A page with a high hub score links to many authoritative pages. As mentioned above, the link-structure based ranking method has been playing an essential role in World Wide Web(WWW), and nowadays, many people recognize the effectiveness and efficiency of it. On the other hand, as Resource Description Framework(RDF) data model forms the foundation of the Semantic Web, any information in the Semantic Web can be expressed with RDF graph, making the ranking algorithm for RDF knowledge bases greatly important. The RDF graph consists of nodes and directional links similar to the Web graph. As a result, the link-structure based ranking method seems to be highly applicable to ranking the Semantic Web resources. However, the information space of the Semantic Web is more complex than that of WWW. For instance, WWW can be considered as one huge class, i.e., a collection of Web pages, which has only a recursive property, i.e., a 'refers to' property corresponding to the hyperlinks. However, the Semantic Web encompasses various kinds of classes and properties, and consequently, ranking methods used in WWW should be modified to reflect the complexity of the information space in the Semantic Web. Previous research addressed the ranking problem of query results retrieved from RDF knowledge bases. Mukherjea and Bamba modified Kleinberg's algorithm in order to apply their algorithm to rank the Semantic Web resources. They defined the objectivity score and the subjectivity score of a resource, which correspond to the authority score and the hub score of Kleinberg's, respectively. They concentrated on the diversity of properties and introduced property weights to control the influence of a resource on another resource depending on the characteristic of the property linking the two resources. A node with a high objectivity score becomes the object of many RDF triples, and a node with a high subjectivity score becomes the subject of many RDF triples. They developed several kinds of Semantic Web systems in order to validate their technique and showed some experimental results verifying the applicability of their method to the Semantic Web. Despite their efforts, however, there remained some limitations which they reported in their paper. First, their algorithm is useful only when a Semantic Web system represents most of the knowledge pertaining to a certain domain. In other words, the ratio of links to nodes should be high, or overall resources should be described in detail, to a certain degree for their algorithm to properly work. Second, a Tightly-Knit Community(TKC) effect, the phenomenon that pages which are less important but yet densely connected have higher scores than the ones that are more important but sparsely connected, remains as problematic. Third, a resource may have a high score, not because it is actually important, but simply because it is very common and as a consequence it has many links pointing to it. In this paper, we examine such ranking problems from a novel perspective and propose a new algorithm which can solve the problems under the previous studies. Our proposed method is based on a class-oriented approach. In contrast to the predicate-oriented approach entertained by the previous research, a user, under our approach, determines the weights of a property by comparing its relative significance to the other properties when evaluating the importance of resources in a specific class. This approach stems from the idea that most queries are supposed to find resources belonging to the same class in the Semantic Web, which consists of many heterogeneous classes in RDF Schema. This approach closely reflects the way that people, in the real world, evaluate something, and will turn out to be superior to the predicate-oriented approach for the Semantic Web. Our proposed algorithm can resolve the TKC(Tightly Knit Community) effect, and further can shed lights on other limitations posed by the previous research. In addition, we propose two ways to incorporate data-type properties which have not been employed even in the case when they have some significance on the resource importance. We designed an experiment to show the effectiveness of our proposed algorithm and the validity of ranking results, which was not tried ever in previous research. We also conducted a comprehensive mathematical analysis, which was overlooked in previous research. The mathematical analysis enabled us to simplify the calculation procedure. Finally, we summarize our experimental results and discuss further research issues.

대학원 재정지원사업의 효과에 관한 추론적 연구: 세계수준의 연구중심대학(WCU) 육성사업 사례 (An Inferential Study on the Effect of a Graduate School Funding Project: Case of World Class University Project's Improving Effect of World University Rankings)

  • 박경호;장덕호
    • 공학교육연구
    • /
    • 제15권4호
    • /
    • pp.101-108
    • /
    • 2012
  • The purpose of this study is to infer how is the effect of a governmental funding project to graduate schools by taking an example of World Class University Project's potential impact on the change of world university rankings in an international university ranking survey. Systematic results show that WCU contributes to improving academic peer reviews for both individual and institutional standings and discipline-based rankings. The potential effect of improving world rankings of participating universities could be ascribed to relatively higher weight of the survey to international peer review and invitation of world class scholars to the participating universities, which is a core device of the project. This implies a need to affirmatively utilize WCU foreign scholars over the course of facilitating international academic networking. The results should also be taken into consideration by universities and the government when developing evaluation systems and restructuring the project.

국내 전개 패션 상품의 브랜드 확장에 관한 연구 - 메인 브랜드가 세컨드 브랜드에 미치는 영향 - (A Study on the Brand Expansion Strategy of Fashion Industry - The Effect of the Main Brand on the Second Brand -)

  • 임성경;유지헌
    • 복식문화연구
    • /
    • 제18권3호
    • /
    • pp.452-464
    • /
    • 2010
  • The purpose of the study was to give a help in making a successful expansion of fashion brand by making a close inquiry into an effect of the main brand in fashion brand on an image of the second brand and into an effect of satisfaction and loyalty for main brand on satisfaction and loyalty for the second brand. The study made a survey of the total eight brands including four main brands and each second brand, and used 217 questionnaires. The results of this study are as follows. First, The main brand image and second brand image did not match. Second, the satisfaction of the main brand affected the satisfaction of their second brand, especially in the main brand of the image, design, user experience, staff friendliness, variety of products and brands on display. Third, the ranking of main brand loyalty and the ranking of second brand loyalty were different. All the main brand loyalty had a significant effect on the second brand. The consumers who preferred the main brand had a high confidence and a strong tendency to repurchase.

혁신활동이 기업의 경영성과에 미치는 영향 (Effect of Firm's Activities on Their Performances)

  • 김광두;홍운선
    • 기술혁신학회지
    • /
    • 제14권2호
    • /
    • pp.373-404
    • /
    • 2011
  • 본 연구의 목적은 혁신활동이 기업의 경영성과에 미치는 영향을 밝히는 데 있다. 이러한 연구는 1960년대 이후 활발하게 진행되어 왔는데, 이론과 달리, 실증분석에서는 혼재된 결과가 나타났다. 실증분석 결과가 이론과 다론 이유는 많이 있지만, 사용되는 통계와 분석 방법의 차이에 기인하는 바가 크다. 본 연구는 이러한 문제의식의 연장선상에서 통계문제를 최소화하기 위해 노력하였다. 특히, 이용 가능한 통계를 최대한 활용하기 위해, 특허청에서 제공되는 특허 출원건수의 전수통계(1990~2008)를, 연구개발은 한국신용평가기관에서 제공되는 연구개발비용 통계(1990~2008)를 사용하였다. 본 연구의 가장 큰 의의는 바로 방대한 통계작업이라 할 수 있다. 적절한 지표 산정을 위해, 주성분 분석을 활용하여 혁신성 지수를 산출하였고, 기업 패널분석과 고성장 기업의 분석에 적절한 분위수 추정을 함께 사용하여 다양한 유형의 기업들에게 미치는 효과를 측정하였다. 분석결과를 보면, 패널 분석에서는 혁신활동이 기업의 경영성과에 미치는 영향이 유의적이지 않지만, 분위수 추정에서는 이와 다른 결론을 도출하였다. 특히, 하위 10%에 해당하는 저성장기업에게는 혁신이 유의하지 않지만, 상위 10%의 고성장 기업에게는 혁신활동이 매우 중요한 영향을 끼치는 것으로 나타난다. 혁신활동이 대기업보다 중소기업에 보다 큰 영향을 미치는 것으로 나타난 점 역시 커다란 시사점이라 할 수 있다.

  • PDF

China's Brain Gain at the High End: An Assessment of Thousand Youth Talents Program

  • Sun, Yutao;Guo, Rongyu;Zhang, Shuai
    • Asian Journal of Innovation and Policy
    • /
    • 제6권3호
    • /
    • pp.274-294
    • /
    • 2017
  • While studies have viewed the effect of Chinese talent-attracting programs launched by government since reform and open door policy, little of them has assessed these programs empirically and pertinently. This article intends to assess an important program - the Thousand Youth Talents Program (TYTP). Frist, this paper proposed a transnational migration matrix of the academics to clarify the dynamic mechanism of academic brain gain at the high end. Then, the Kaplan-Meier analysis and Cox regression model are used to empirically analyze the policy effect of TYTP. The results show that, academic ability have double edged impacts on brain gain at the high end, some scholars whose last employer's academic ranking is world's Top100 have stronger willing to return, and the negative effect of academic ranking decreases with time passing; while scholars with a tenure-track position, a tenure position or a permanent position tend to stay overseas, and the hazard rate of staying increases with age. The older scholars have more intentions to go back China, while gender was not a significant factor influencing academic return at the high end. That is, the talent-attracting programs has partly succeeded in bringing back the academics at the high end.

트렌드 지수를 반영한 블로그 랭킹 알고리즘 (The Blog Ranking Algorithm Reflecting Trend Index)

  • 이용석;김형중
    • 디지털콘텐츠학회 논문지
    • /
    • 제18권3호
    • /
    • pp.551-558
    • /
    • 2017
  • 블로그의 성장은 다양한 정보제공이라는 긍정적 측면과 마케팅적 활용이라는 부정적 수단으로 사용되고 있는 문제를 가지고 있다. 본 연구는 대형 포털의 블로그 포스트의 랭킹 결과를 OpenAPI를 이용하여 수집하였고, 탐색적 데이터 분석기법을 통해서 상위 랭크된 블로그의 특징들을 조사하였다. 분석 결과를 보면 상위 랭크에 영향을 주는 요소로는 블로거의 영향력과 포스트의 최근 생성일에 관련성이 높은 것을 알 수 있었다. 이런 평가 알고리즘의 약점으로 인해 파워 블로거의 포스트 중심으로 검색 결과를 편중되게 보여주는 문제가 있었다. 본 연구에서는 다양한 대중의 관심사를 나타내는 트렌드 지수를 통해 랭킹 점수 적용의 공정성을 확보하고, 전문가에 의해 검증된 신뢰 DB정보를 추가하여 컨텐츠 신뢰성을 높이는 알고리즘을 제안하였다. 개선된 알고리즘을 맛집 검색 결과가 실제 지역 학생들의 추천 맛집정보와의 유사도가 높은 것을 확인하였다. 개선된 알고리즘으로 좀 더 신뢰할 수 있는 정보제공이 가능해 졌으며, 방문자수 증가시키는 불법 앱에 의한 순위 조작이 어려워지는 부가적 개선 효과가 기대된다.

Composite Measures of Supercomputer Technology

  • Kim, Nam-Gyu;On, Noo Ri;Koh, Myoung-Ju;Lee, JongSuk Ruth;Cho, Keun-Tae
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제13권8호
    • /
    • pp.4142-4159
    • /
    • 2019
  • We have developed composite measures of supercomputer technology, reflecting various factors of supercomputers using Martino's scoring model. CPUs, accelerators, memory, interconnection networks, and power consumption are chosen as factors of the model. The weight values of the factors are derived based on a survey of 129 domestic and international experts. The measured values are then standardized to integrate measurement units of the factors in the model. This model has been applied to 50 supercomputers, and rank correlation analysis was performed using representative measures. As a consequence, the ranking drastically changes except for the 1st and 2nd supercomputers on the TOP500. In addition, the characteristics of memory and interconnection networks influence the ranking, and the results demonstrate that the proposed model has low correlations with HPL and HPCG but a high correlation with Green500. This indicates that power consumption is an important factor that has a significant effect on the measures of supercomputer technology. In addition, it is determined that the differences between the HPL ranking and the proposed model ranking are influenced by power consumption, CPU theoretical peak performance, and main memory bandwidth in order of significance. In conclusion, the composite measures proposed in this study are more suitable for comprehensively describing supercomputer technology than existing performance measures. The findings of this study are expected to support decision making related to management and policy in the procurement and operation of supercomputers.