• 제목/요약/키워드: knowledge network

검색결과 1,995건 처리시간 0.033초

In-silico annotation of the chemical composition of Tibetan tea and its mechanism on antioxidant and lipid-lowering in mice

  • Ning Wang ;Linman Li ;Puyu Zhang;Muhammad Aamer Mehmood ;Chaohua Lan;Tian Gan ;Zaixin Li ;Zhi Zhang ;Kewei Xu ;Shan Mo ;Gang Xia ;Tao Wu ;Hui Zhu
    • Nutrition Research and Practice
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    • 제17권4호
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    • pp.682-697
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    • 2023
  • BACKGROUND/OBJECTIVES: Tibetan tea is a kind of dark tea, due to the inherent complexity of natural products, the chemical composition and beneficial effects of Tibetan tea are not fully understood. The objective of this study was to unravel the composition of Tibetan tea using knowledge-guided multilayer network (KGMN) techniques and explore its potential antioxidant and hypolipidemic mechanisms in mice. MATERIALS/METHODS: The C57BL/6J mice were continuously gavaged with Tibetan tea extract (T group), green tea extract (G group) and ddH2O (H group) for 15 days. The activity of total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) in mice was detected. Transcriptome sequencing technology was used to investigate the molecular mechanisms underlying the antioxidant and lipid-lowering effects of Tibetan tea in mice. Furthermore, the expression levels of liver antioxidant and lipid metabolism related genes in various groups were detected by the real-time quantitative polymerase chain reaction (qPCR) method. RESULTS: The results showed that a total of 42 flavonoids are provisionally annotated in Tibetan tea using KGMN strategies. Tibetan tea significantly reduced body weight gain and increased T-AOC and SOD activities in mice compared with the H group. Based on the results of transcriptome and qPCR, it was confirmed that Tibetan tea could play a key role in antioxidant and lipid lowering by regulating oxidative stress and lipid metabolism related pathways such as insulin resistance, P53 signaling pathway, insulin signaling pathway, fatty acid elongation and fatty acid metabolism. CONCLUSIONS: This study was the first to use computational tools to deeply explore the composition of Tibetan tea and revealed its potential antioxidant and hypolipidemic mechanisms, and it provides new insights into the composition and bioactivity of Tibetan tea.

IT-BPO 기업의 혁신역량과 흡수역량 요인이 시장지향성, 기술지향성 및 경영성과에 미치는 영향 (The Effect of the Innovation Capability and the Absorptive Capacity on Market Orientation, Technology Orientation, and Business Performance of IT-BPO Firms)

  • 김완강;이소영
    • 벤처혁신연구
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    • 제6권1호
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    • pp.115-137
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    • 2023
  • 본 연구에서는 디지털 전환시대에 선도적인 관점에서 신기술을 흡수하고 혁신적 변화가 요구되고 있는 IT-BPO 기업을 대상으로 조직 핵심역량과 흡수역량이 시장지향성 및 기술지향성에 미치는 관계를 분석하고, 나아가 경영성과에 미치는 관계를 분석하고자 하였다. 이를 위한 연구방법으로 국내 IT-BPO 비즈니스를 수행하고 있는 업체를 대상으로 온라인 전문리서치 업체 및 오프라인 설문조사를 병행하여 291부를 회수하였으며, 분석방법으로는 기술통계와 신뢰도 분석에는 SPSS 23, 타당성, 매개효과를 포함한 연구가설 검증은 AMOS23을 이용하여 분석하였다. 주요 분석결과, 첫째, 혁신역량과 흡수역량 요인이 시장지향성에 미치는 관계에서는 학습역량과 지식네트워크 역량이 시장지향성에 통계적으로 유의한 정(+)의 영향을 미치는 것으로 나타났다. 혁신역량과 흡수역량 요인이 기술지향성에 미치는 관계에서는 R&D역량, 잠재적 흡수역량 및 실현적 흡수역량이 통계적으로 유의한 정(+)의 영향을 미치는 것으로 나타났다. 둘째, 혁신역량과 흡수역량 요인이 경영성과에 미치는 영향 관계에서는 R&D역량만이 통계적으로 유의한 정(+)의 영향 관계를 가지는 것으로 나타났다. 셋째, 시장지향성과 기술지향성이 경영성과에 미치는 관계에서는 시장지향성과 기술지향성 모두 경영성과에 통계적으로 유의한 정(+)의 영향을 미치는 것으로 나타났다. 이러한 연구결과는 IT-BPO 기업이 성장과 가치창출을 높이기 위해 추구하는 시장지향성이나 기술지향성 유형에 따라 효과적인 역량요인을 제시함으로써 전략 목적에 따른 차별적 역량 강화방안에 하나에 시사점을 제시할 것으로 보인다.

챗GPT 등장 이후 인공지능 환각 연구의 문헌 검토: 아카이브(arXiv)의 논문을 중심으로 (Literature Review of AI Hallucination Research Since the Advent of ChatGPT: Focusing on Papers from arXiv)

  • 박대민;이한종
    • 정보화정책
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    • 제31권2호
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    • pp.3-38
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    • 2024
  • 환각은 대형언어모형이나 대형 멀티모달 모형의 활용을 막는 큰 장벽이다. 본 연구에서는 최신 환각 연구 동향을 살펴보기 위해 챗 GPT 등장 이후인 2022년 12월부터 2024년 1월까지 아카이브(arXiv)에서 초록에 '환각'이 포함된 컴퓨터과학 분야 논문 654건을 수집해 빈도분석, 지식연결망 분석, 문헌 검토를 수행했다. 이를 통해 분야별 주요 저자, 주요 키워드, 주요 분야, 분야 간 관계를 분석했다. 분석 결과 '계산 및 언어'와 '인공지능', '컴퓨터비전 및 패턴인식', '기계학습' 분야의 연구가 활발했다. 이어 4개 주요 분야 연구 동향을 주요 저자를 중심으로 데이터 측면, 환각 탐지 측면, 환각 완화 측면으로 나눠 살펴보았다. 주요 연구 동향으로는 지도식 미세조정(SFT)과 인간 피드백 기반 강화학습(RLHF)을 통한 환각 완화, 생각의 체인(CoT) 등 추론 강화, 자동화와 인간 개입의 병행, 멀티모달 AI의 환각 완화에 대한 관심 증가 등을 들 수 있다. 본 연구는 환각 연구 최신 동향을 파악함으로써 공학계는 물론 인문사회계 후속 연구의 토대가 될 것으로 기대한다.

머신 러닝을 이용한 밸브 사이즈 및 종류 예측 모델 개발 (Data-driven Modeling for Valve Size and Type Prediction Using Machine Learning)

  • 김찬호;최민식;주종효;이아름;윤건;조성호;김정환
    • Korean Chemical Engineering Research
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    • 제62권3호
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    • pp.214-224
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    • 2024
  • 밸브는 유량과 압력 조절 등의 중요한 역할을 수행하며, 적절한 밸브 사이즈와 유형 선택이 필요하다. Engineering Procurement Construction (EPC) 산업에선 밸브 사이즈 계수(Cv)의 수식적 계산을 바탕으로 사이즈와 유형을 선정해왔으나 이러한 방식은 전문가의 많은 시간과 비용이 요구되어 비효율적이다. 본 연구는 이를 해결하기위해 머신 러닝기법을 이용한 밸브 사이즈 및 유형 예측 모델을 개발하였다. Artificial neural network (ANN), Random Forest, XGBoost, Catboost의알고리즘을 적용하여 모델들을 개발하였으며, 평가 지표로는 사이즈 예측에는 Normalized root mean squared error (NRMSE)와 R2를, 종류 예측에는 F1 score를 적용하였다. 또한, 유체 상에 따른 영향을 확인하고자 유체 전체, 액체, 기체, 스팀의 4개의 데이터 세트로 사례 연구를 진행하였다. 연구 결과, 사이즈의 경우 전체, 액체, 기체에선 Catboost(R2기준, 전체: 0.99216, 액체: 0.98602, 기체: 0.99300. NRMSE 기준, 전체: 0.04072, 액체: 0.04886, 기체: 0.03619)가, 스팀에선 Random Forest가(R2: 0.99028, NRMSE: 0.03493) 가장 뛰어난 모델임을 확인하였다. 종류의 경우 Catboost가 모든 데이터에서 가장 높은 성과를 제시하였다(F1 score 기준, 전체: 0.95766, 액체: 0.96264, 기체: 0.95770, 스팀: 1.0000). 본 연구에서 제안한 모델들을 적용할 경우, 주어진 조건에 따른 밸브 선택을 도와 의사결정 속도를 높여줄 것으로 기대된다.

Perceptional Change of a New Product, DMB Phone

  • Kim, Ju-Young;Ko, Deok-Im
    • 마케팅과학연구
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    • 제18권3호
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    • pp.59-88
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    • 2008
  • Digital Convergence means integration between industry, technology, and contents, and in marketing, it usually comes with creation of new types of product and service under the base of digital technology as digitalization progress in electro-communication industries including telecommunication, home appliance, and computer industries. One can see digital convergence not only in instruments such as PC, AV appliances, cellular phone, but also in contents, network, service that are required in production, modification, distribution, re-production of information. Convergence in contents started around 1990. Convergence in network and service begins as broadcasting and telecommunication integrates and DMB(digital multimedia broadcasting), born in May, 2005 is the symbolic icon in this trend. There are some positive and negative expectations about DMB. The reason why two opposite expectations exist is that DMB does not come out from customer's need but from technology development. Therefore, customers might have hard time to interpret the real meaning of DMB. Time is quite critical to a high tech product, like DMB because another product with same function from different technology can replace the existing product within short period of time. If DMB does not positioning well to customer's mind quickly, another products like Wibro, IPTV, or HSPDA could replace it before it even spreads out. Therefore, positioning strategy is critical for success of DMB product. To make correct positioning strategy, one needs to understand how consumer interprets DMB and how consumer's interpretation can be changed via communication strategy. In this study, we try to investigate how consumer perceives a new product, like DMB and how AD strategy change consumer's perception. More specifically, the paper segment consumers into sub-groups based on their DMB perceptions and compare their characteristics in order to understand how they perceive DMB. And, expose them different printed ADs that have messages guiding consumer think DMB in specific ways, either cellular phone or personal TV. Research Question 1: Segment consumers according to perceptions about DMB and compare characteristics of segmentations. Research Question 2: Compare perceptions about DMB after AD that induces categorization of DMB in direction for each segment. If one understand and predict a direction in which consumer perceive a new product, firm can select target customers easily. We segment consumers according to their perception and analyze characteristics in order to find some variables that can influence perceptions, like prior experience, usage, or habit. And then, marketing people can use this variables to identify target customers and predict their perceptions. If one knows how customer's perception is changed via AD message, communication strategy could be constructed properly. Specially, information from segmented customers helps to develop efficient AD strategy for segment who has prior perception. Research framework consists of two measurements and one treatment, O1 X O2. First observation is for collecting information about consumer's perception and their characteristics. Based on first observation, the paper segment consumers into two groups, one group perceives DMB similar to Cellular phone and the other group perceives DMB similar to TV. And compare characteristics of two segments in order to find reason why they perceive DMB differently. Next, we expose two kinds of AD to subjects. One AD describes DMB as Cellular phone and the other Ad describes DMB as personal TV. When two ADs are exposed to subjects, consumers don't know their prior perception of DMB, in other words, which subject belongs 'similar-to-Cellular phone' segment or 'similar-to-TV' segment? However, we analyze the AD's effect differently for each segment. In research design, final observation is for investigating AD effect. Perception before AD is compared with perception after AD. Comparisons are made for each segment and for each AD. For the segment who perceives DMB similar to TV, AD that describes DMB as cellular phone could change the prior perception. And AD that describes DMB as personal TV, could enforce the prior perception. For data collection, subjects are selected from undergraduate students because they have basic knowledge about most digital equipments and have open attitude about a new product and media. Total number of subjects is 240. In order to measure perception about DMB, we use indirect measurement, comparison with other similar digital products. To select similar digital products, we pre-survey students and then finally select PDA, Car-TV, Cellular Phone, MP3 player, TV, and PSP. Quasi experiment is done at several classes under instructor's allowance. After brief introduction, prior knowledge, awareness, and usage about DMB as well as other digital instruments is asked and their similarities and perceived characteristics are measured. And then, two kinds of manipulated color-printed AD are distributed and similarities and perceived characteristics for DMB are re-measured. Finally purchase intension, AD attitude, manipulation check, and demographic variables are asked. Subjects are given small gift for participation. Stimuli are color-printed advertising. Their actual size is A4 and made after several pre-test from AD professionals and students. As results, consumers are segmented into two subgroups based on their perceptions of DMB. Similarity measure between DMB and cellular phone and similarity measure between DMB and TV are used to classify consumers. If subject whose first measure is less than the second measure, she is classified into segment A and segment A is characterized as they perceive DMB like TV. Otherwise, they are classified as segment B, who perceives DMB like cellular phone. Discriminant analysis on these groups with their characteristics of usage and attitude shows that Segment A knows much about DMB and uses a lot of digital instrument. Segment B, who thinks DMB as cellular phone doesn't know well about DMB and not familiar with other digital instruments. So, consumers with higher knowledge perceive DMB similar to TV because launching DMB advertising lead consumer think DMB as TV. Consumers with less interest on digital products don't know well about DMB AD and then think DMB as cellular phone. In order to investigate perceptions of DMB as well as other digital instruments, we apply Proxscal analysis, Multidimensional Scaling technique at SPSS statistical package. At first step, subjects are presented 21 pairs of 7 digital instruments and evaluate similarity judgments on 7 point scale. And for each segment, their similarity judgments are averaged and similarity matrix is made. Secondly, Proxscal analysis of segment A and B are done. At third stage, get similarity judgment between DMB and other digital instruments after AD exposure. Lastly, similarity judgments of group A-1, A-2, B-1, and B-2 are named as 'after DMB' and put them into matrix made at the first stage. Then apply Proxscal analysis on these matrixes and check the positional difference of DMB and after DMB. The results show that map of segment A, who perceives DMB similar as TV, shows that DMB position closer to TV than to Cellular phone as expected. Map of segment B, who perceive DMB similar as cellular phone shows that DMB position closer to Cellular phone than to TV as expected. Stress value and R-square is acceptable. And, change results after stimuli, manipulated Advertising show that AD makes DMB perception bent toward Cellular phone when Cellular phone-like AD is exposed, and that DMB positioning move towards Car-TV which is more personalized one when TV-like AD is exposed. It is true for both segment, A and B, consistently. Furthermore, the paper apply correspondence analysis to the same data and find almost the same results. The paper answers two main research questions. The first one is that perception about a new product is made mainly from prior experience. And the second one is that AD is effective in changing and enforcing perception. In addition to above, we extend perception change to purchase intention. Purchase intention is high when AD enforces original perception. AD that shows DMB like TV makes worst intention. This paper has limitations and issues to be pursed in near future. Methodologically, current methodology can't provide statistical test on the perceptual change, since classical MDS models, like Proxscal and correspondence analysis are not probability models. So, a new probability MDS model for testing hypothesis about configuration needs to be developed. Next, advertising message needs to be developed more rigorously from theoretical and managerial perspective. Also experimental procedure could be improved for more realistic data collection. For example, web-based experiment and real product stimuli and multimedia presentation could be employed. Or, one can display products together in simulated shop. In addition, demand and social desirability threats of internal validity could influence on the results. In order to handle the threats, results of the model-intended advertising and other "pseudo" advertising could be compared. Furthermore, one can try various level of innovativeness in order to check whether it make any different results (cf. Moon 2006). In addition, if one can create hypothetical product that is really innovative and new for research, it helps to make a vacant impression status and then to study how to form impression in more rigorous way.

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통합과학 교과 역량에 대한 교사들의 인식 분석 (Analysis of Teachers' Perceptions on the Subject Competencies of Integrated Science)

  • 안유민;변태진
    • 한국과학교육학회지
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    • 제40권2호
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    • pp.97-111
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    • 2020
  • 2015 개정 교육과정에서는 융복합적 사고력 신장을 위해 '통합과학'을 신설하고, 문이과 구분 없이 모든 학생이 배우도록 공통 과목으로 지정하였다. 또한 2015 개정 교육과정에서는 이전 교육과정과 차별화되는 특징으로 '역량'을 도입하였다. 2015 개정 교육과정에서 역량은 범교과적 성격의 핵심역량과 교과의 학문적 지식과 기능에 기반한 교과 역량으로 구분된다. 과학과 교과 역량에는 과학적 사고력, 과학적 탐구 능력, 과학적 문제 해결력, 과학적 의사소통 능력, 과학적 참여와 평생 학습 능력 5가지로 이루어져 있다. 하지만 교육과정 문서의 교과 역량에 대한 설명은 불충분하며, 역량에 대한 전문가들의 인식 역시 통일되어 있지 못한 실정이다. 이에 본 연구에서는 역량 기반 교육이 학교 현장에 제대로 적용되기 위해서는 과학 교사들이 역량에 대한 이해가 선행되어야 된다고 판단하여 고등학교 과학 교사들을 대상으로 과학과 교과 역량에 대한 인식을 조사하였다. 우선 통합과학 성취기준에 대한 이해가 높은 전문가 워킹 그룹 운영을 통해 통합과학의 성취기준과 교과 역량의 관계를 분석하였다. 그 다음으로 고등학교 과학 교사 31명에 대상으로 서술형 설문을 통해 5가지 교과 역량에 대한 인식을 알아보았다. 교사의 응답은 언어 네트워크 분석 기법을 통해 분석하였다. 분석 결과 과학적 탐구 능력, 과학적 의사소통 능력, 과학적 참여와 평생 학습 능력 3개 교과 역량은 교사들이 생각하는 바와 교육과정 문서에서 제시한 정의와 유사성이 높았으나, 과학적 사고력, 과학적 문제 해결력의 경우 교사들의 인식과 교육과정 문서상의 정의와 어느 정도 간극이 존재하였다. 또한 5개 역량에 대해 교사들의 인식을 종합적으로 분석한 결과를 보면 5개 교과 역량이 상호배타적이나 독립적이기 보다 연관성이 매우 높음을 알 수 있었다.

정보시스템의 지속적 사용에서 경험의 역할에 대한 분석 (An Analysis of the Roles of Experience in Information System Continuance)

  • 이웅규
    • Asia pacific journal of information systems
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    • 제21권4호
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    • pp.45-62
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    • 2011
  • The notion of information systems (IS) continuance has recently emerged as one of the most important research issues in the field of IS. A great deal of research has been conducted thus far on the basis of theories adapted from various disciplines including consumer behaviors and social psychology, in addition to theories regarding information technology (IT) acceptance. This previous body of knowledge provides a robust research framework that can already account for the determination of IS continuance; however, this research points to other, thus-far-unelucidated determinant factors such as habit, which were not included in traditional IT acceptance frameworks, and also re-emphasizes the importance of emotion-related constructs such as satisfaction in addition to conscious intention with rational beliefs such as usefulness. Experiences should also be considered one of the most important factors determining the characteristics of information system (IS) continuance and the features distinct from those determining IS acceptance, because more experienced users may have more opportunities for IS use, which would allow them more frequent use than would be available to less experienced or non-experienced users. Interestingly, experience has dual features that may contradictorily influence IS use. On one hand, attitudes predicated on direct experience have been shown to predict behavior better than attitudes from indirect experience or without experience; as more information is available, direct experience may render IS use a more salient behavior, and may also make IS use more accessible via memory. Therefore, experience may serve to intensify the relationship between IS use and conscious intention with evaluations, On the other hand, experience may culminate in the formation of habits: greater experience may also imply more frequent performance of the behavior, which may lead to the formation of habits, Hence, like experience, users' activation of an IS may be more dependent on habit-that is, unconscious automatic use without deliberation regarding the IS-and less dependent on conscious intentions, Furthermore, experiences can provide basic information necessary for satisfaction with the use of a specific IS, thus spurring the formation of both conscious intentions and unconscious habits, Whereas IT adoption Is a one-time decision, IS continuance may be a series of users' decisions and evaluations based on satisfaction with IS use. Moreover. habits also cannot be formed without satisfaction, even when a behavior is carried out repeatedly. Thus, experiences also play a critical role in satisfaction, as satisfaction is the consequence of direct experiences of actual behaviors. In particular, emotional experiences such as enjoyment can become as influential on IS use as are utilitarian experiences such as usefulness; this is especially true in light of the modern increase in membership-based hedonic systems - including online games, web-based social network services (SNS), blogs, and portals-all of which attempt to provide users with self-fulfilling value. Therefore, in order to understand more clearly the role of experiences in IS continuance, analysis must be conducted under a research framework that includes intentions, habits, and satisfaction, as experience may not only have duration-based moderating effects on the relationship between both intention and habit and the activation of IS use, but may also have content-based positive effects on satisfaction. This is consistent with the basic assumptions regarding the determining factors in IS continuance as suggested by Oritz de Guinea and Markus: consciousness, emotion, and habit. The principal objective of this study was to explore and assess the effects of experiences in IS continuance, with special consideration given to conscious intentions and unconscious habits, as well as satisfaction. IN service of this goal, along with a review of the relevant literature regarding the effects of experiences and habit on continuous IS use, this study suggested a research model that represents the roles of experience: its moderating role in the relationships of IS continuance with both conscious intention and unconscious habit, and its antecedent role in the development of satisfaction. For the validation of this research model. Korean university student users of 'Cyworld', one of the most influential social network services in South Korea, were surveyed, and the data were analyzed via partial least square (PLS) analysis to assess the implications of this study. In result most hypotheses in our research model were statistically supported with the exception of one. Although one hypothesis was not supported, the study's findings provide us with some important implications. First the role of experience in IS continuance differs from its role in IS acceptance. Second, the use of IS was explained by the dynamic balance between habit and intention. Third, the importance of satisfaction was confirmed from the perspective of IS continuance with experience.

사회과학 연구에 있어 인터넷 및 상업용 통신망을 이용한 전자설문 조사방법의 활용 (Toward a Social Sciences Methodology for Electronic Survey Research on the Internet or Personal Computer check)

  • 홍용기;이홍기;채수경
    • 경영과정보연구
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    • 제3권
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    • pp.287-316
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    • 1999
  • Cyberspace permits us to more beyond traditional face-to-face, mail and telephone surveys, yet still to examine basic issues regarding the quality of data collection: sampling, questionnaire design, survey distribution, means of response, and database creation. This article address each of these issues by contrasting and comparing traditional survey methods(Paper-and-Pencil) with Internet or Personal Computer networks-mediated (Screen-and-Keyboard) survey methods also introduces researchers to this revolutionary and innovative tool and outlines a variety of practical methods for using the Internet or Personal Computer Networks. The revolution in telecommunications technology has fostered the rapid growth of the Internet all over the world. The Internet is a massive global network and comprising many national and international networks of interconnected computers. The Internet or Personal Computer Networks could be the comprehensive interactive tool that will facilitate the development of the skills. The Internet or Personal Computer Networks provides a virtual frontier to expand our access to information and to increase our knowledge and understanding of public opinion, political behavior, social trends and lifestyles through survey research. Comparable to other technological advancements, the Internet or Personal Computer Networks presents opportunities that will impact significantly on the process and quality of survey research now and in the twenty-first century. There are trade-offs between traditional and the Internet or Personal Computer Networks survey. The Internet or Personal Computer Networks is an important channel for obtaining information for target participants. The cost savings in time, efforts, and material were substantial. The use of the Internet or Personal Computer Networks survey tool will increase the quality of research environment. There are several limitations to the Internet or Personal Computer Network survey approach. It requires the researcher to be familiar with Internet navigation and E-mail, it is essential for this process. The use of Listserv and Newsgroup result in a biased sample of the population of corporate trainers. However, it is this group that participates in technology and is in the fore front of shaping the new organizations of interest, and therefore it consists of appropriate participants. If this survey method becomes popular and is too frequently used, potential respondents may become as annoyed with E-mail as the sometimes are with mail survey and junk mail. Being a member of the Listserv of Newsgroup may moderate that reaction. There is a need to determine efficient, effective ways for the researcher to strip identifiers from E-mail, so that respondents remain anonymous, while simultaneously blocking a respondent from responding to a particular survey instrument more than once. The optimum process would be on that is initiated by the researcher : simple, fast and inexpensive to administer and has credibility with respondents. This would protect the legitimacy of the sample and anonymity. Creating attractive Internet or Personal Computer Networks survey formats that build on the strengths of standardized structures but also capitalize on the dynamic and interactive capability of the medium. Without such innovations in survey design, it is difficult to imagine why potential survey respondents would use their time to answer questions. More must be done to create diverse and exciting ways of building an credibility between respondents and researchers on the Internet or Personal Computer Networks. We believe that the future of much exciting research is based in the Electronic survey research. The ability to communicate across distance, time, and national boundaries offers great possibilities for studying the ways in which technology and technological discourse are shaped. used, and disseminated ; the many recent doctoral dissertations that treat some aspect of electronic survey research testify to the increase focus on the Internet or Personal Computer Networks. Thus, scholars should begin a serious conversation about the methodological issues of conducting research In cyberspace. Of all the disciplines, Internet or Personal Computer Networks, emphasis on the relationship between technology and human communication, should take the lead in considering research in the cyberspace.

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한반도 일원의 중력측정 및 보정의 정밀화와 고밀도 부우게이상 (On the Improvement of Precision in Gravity Surveying and Correction, and a Dense Bouguer Anomaly in and Around the Korean Peninsula)

  • 신영홍;양철수;옥수석;최광선
    • 한국지구과학회지
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    • 제24권3호
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    • pp.205-215
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    • 2003
  • 정밀하고 밀도 높은 부우게이상자료는 지구물리학과 물리측지학적인 측면에서 중요한 기초자료가 된다. 이를 위해서 정밀한 절대중력기준점망의 설치외에도 두 가지 측면을 고려해야 하는데, 하나는 중력측정과 보정의 정밀도를 향상시키는 것이며, 다른 하나는 측점의 밀도를 높이는 일이다. 중력측정에서 GPS를 어떻게 적절히 이용할 것인가에 대해서 알아보았는데, 40km이내의 기선거리에서 두 대의 측지용 GPS수신기를 이용하면, 5분간의 GPS측정으로도 충분하다고 여겨진다. 이 경우 PNU95 지오이드모델과 같은 정밀한 지오이드모델을 사용하여야 한다, 이 방법을 적용함으로써, 비용 및 시간과 인력을 줄일 수 있을 뿐만 아니라 질적인 측면에서도 향상을 가져온다. 또 교점오차를 보정하고 지형효과를 정밀하게 계산하기 위해 컴퓨터 프로그램을 개발했다. 중력탐사에서 같은 지점에서 중복 측정하는 것은 스프링의 변이를 보정하는 것뿐만 아니라 망조정을 적용함으로써 결과들에 대해 통계적으로 접근하는 것을 가능하게 한다. 그럼으로써 다양한 원인에 기인한 큰 오차를 쉽게 찾아내고 보정하여 자료의 질을 향상시킬 수 있으며, 또한 측정의 질을 평가할 수 있다. 최근의 컴퓨터 기술과 디지털 고도자료의 발달도 좀더 정밀한 지형보정을 사용하여 부우게이상의 질을 향상하도록 우리를 고무하고 있다. 본 연구에서는 육상중력, 선상중력, 북한의 부우게이상도, 일본의 중력자료, 고도위성자료, EGM96 지오포텐셜 자료 등, 다양한 중력자료를 입수하였다. 따라서, 이들 자료를 계산하고 편집하여 한반도 일원의 정밀 부우게이상도를 작성할 수 있었는데, 이것은 지구물리학과 물리측지학의 응용에 유용한 자료가 될 것이다.

SVM을 이용한 VKOSPI 일 중 변화 예측과 실제 옵션 매매에의 적용 (VKOSPI Forecasting and Option Trading Application Using SVM)

  • 라윤선;최흥식;김선웅
    • 지능정보연구
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    • 제22권4호
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    • pp.177-192
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    • 2016
  • 기계학습(Machine Learning)은 인공 지능의 한 분야로, 데이터를 이용하여 기계를 학습시켜 기계 스스로가 데이터 분석 및 예측을 하게 만드는 것과 관련한 컴퓨터 과학의 한 영역을 일컫는다. 그중에서 SVM(Support Vector Machines)은 주로 분류와 회귀 분석을 목적으로 사용되는 모델이다. 어느 두 집단에 속한 데이터들에 대한 정보를 얻었을 때, SVM 모델은 주어진 데이터 집합을 바탕으로 하여 새로운 데이터가 어느 집단에 속할지를 판단해준다. 최근 들어서 많은 금융전문가는 기계학습과 막대한 데이터가 존재하는 금융 분야와의 접목 가능성을 보며 기계학습에 집중하고 있다. 그러면서 각 금융사는 고도화된 알고리즘과 빅데이터를 통해 여러 금융업무 수행이 가능한 로봇(Robot)과 투자전문가(Advisor)의 합성어인 로보어드바이저(Robo-Advisor) 서비스를 발 빠르게 제공하기 시작했다. 따라서 현재의 금융 동향을 고려하여 본 연구에서는 기계학습 방법의 하나인 SVM을 활용하여 매매성과를 올리는 방법에 대해 제안하고자 한다. SVM을 통한 예측대상은 한국형 변동성지수인 VKOSPI이다. VKOSPI는 금융파생상품의 한 종류인 옵션의 가격에 영향을 미친다. VKOSPI는 흔히 말하는 변동성과 같고 VKOSPI 값은 옵션의 종류와 관계없이 옵션 가격과 정비례하는 특성이 있다. 그러므로 VKOSPI의 정확한 예측은 옵션 매매에서의 수익을 낼 수 있는 중요한 요소 중 하나이다. 지금까지 기계학습을 기반으로 한 VKOSPI의 예측을 다룬 연구는 없었다. 본 연구에서는 SVM을 통해 일 중의 VKOSPI를 예측하였고, 예측 내용을 바탕으로 옵션 매매에 대한 적용 가능 여부를 실험하였으며 실제로 향상된 매매 성과가 나타남을 증명하였다.