• Title/Summary/Keyword: 학술연구자

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Recommending Core and Connecting Keywords of Research Area Using Social Network and Data Mining Techniques (소셜 네트워크와 데이터 마이닝 기법을 활용한 학문 분야 중심 및 융합 키워드 추천 서비스)

  • Cho, In-Dong;Kim, Nam-Gyu
    • Journal of Intelligence and Information Systems
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    • v.17 no.1
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    • pp.127-138
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    • 2011
  • The core service of most research portal sites is providing relevant research papers to various researchers that match their research interests. This kind of service may only be effective and easy to use when a user can provide correct and concrete information about a paper such as the title, authors, and keywords. However, unfortunately, most users of this service are not acquainted with concrete bibliographic information. It implies that most users inevitably experience repeated trial and error attempts of keyword-based search. Especially, retrieving a relevant research paper is more difficult when a user is novice in the research domain and does not know appropriate keywords. In this case, a user should perform iterative searches as follows : i) perform an initial search with an arbitrary keyword, ii) acquire related keywords from the retrieved papers, and iii) perform another search again with the acquired keywords. This usage pattern implies that the level of service quality and user satisfaction of a portal site are strongly affected by the level of keyword management and searching mechanism. To overcome this kind of inefficiency, some leading research portal sites adopt the association rule mining-based keyword recommendation service that is similar to the product recommendation of online shopping malls. However, keyword recommendation only based on association analysis has limitation that it can show only a simple and direct relationship between two keywords. In other words, the association analysis itself is unable to present the complex relationships among many keywords in some adjacent research areas. To overcome this limitation, we propose the hybrid approach for establishing association network among keywords used in research papers. The keyword association network can be established by the following phases : i) a set of keywords specified in a certain paper are regarded as co-purchased items, ii) perform association analysis for the keywords and extract frequent patterns of keywords that satisfy predefined thresholds of confidence, support, and lift, and iii) schematize the frequent keyword patterns as a network to show the core keywords of each research area and connecting keywords among two or more research areas. To estimate the practical application of our approach, we performed a simple experiment with 600 keywords. The keywords are extracted from 131 research papers published in five prominent Korean journals in 2009. In the experiment, we used the SAS Enterprise Miner for association analysis and the R software for social network analysis. As the final outcome, we presented a network diagram and a cluster dendrogram for the keyword association network. We summarized the results in Section 4 of this paper. The main contribution of our proposed approach can be found in the following aspects : i) the keyword network can provide an initial roadmap of a research area to researchers who are novice in the domain, ii) a researcher can grasp the distribution of many keywords neighboring to a certain keyword, and iii) researchers can get some idea for converging different research areas by observing connecting keywords in the keyword association network. Further studies should include the following. First, the current version of our approach does not implement a standard meta-dictionary. For practical use, homonyms, synonyms, and multilingual problems should be resolved with a standard meta-dictionary. Additionally, more clear guidelines for clustering research areas and defining core and connecting keywords should be provided. Finally, intensive experiments not only on Korean research papers but also on international papers should be performed in further studies.

An assessment of statistical errors of articles in the Journal of Korean Academy of Prosthodontics: Comparison between Korean version and English version (대한치과보철학회지에 게재된 논문의 통계적 오류: 국문논문과 영문논문의 비교)

  • Park, Dong-Gyu;Choi, Yong-Geun;Kim, Young-Su;Shin, Sang-Wan
    • The Journal of Korean Academy of Prosthodontics
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    • v.47 no.3
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    • pp.273-285
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    • 2009
  • Statement of problem: The aim of dental research is to advance scientific knowledge and leads to improvement in the treatment and prevention of dental disease. Utilizing an effective research design and adequate statistical methods are essential procedures ensuring that the results of researches are based on evidences. A research should utilize proper statistical methods without statistical errors; Otherwise, it could adversely affect clinical practice and future research. Purpose: This study was made to investigate the statistical methods used in the Journal of Korean Academy of Prosthodontics (JKAP) and then to assess them for the statistical errors. Material and methods: Among the total of 399 articles in the JKAP published from 2000 to 2006, 292 articles using statistics were reviewed. The validity of the statistical methods used in them were assessed using a checklist based on the guideline for statistical reporting in the uniform requirements for manuscripts submitted to biomedical journals by International Committee of Medical Journal Editors. The checklist consisted of three categories of statistical errors: 1) Unspecified computer statistical packages, 2) Inadequate description of statistical methods, 3) Misuse of statistical terms. Then, the results were compared between the Korean version and the English version in the JKAP. Results: Among the 212 articles using statistics in the Korean version, 115 articles (54%) and among the 80 articles using statistics in the English version, 47 articles (59%) were shown to have unspecified computer statistical packages without statistically significant difference (P = .66). Likewise, 101 articles (48%) in the Korean version and 25 articles (31%) in the English version were shown to have the inadequate description of statistical methods without statistically significant difference (P = .09). However, 114 articles (54%) in the Korean version and 19 articles (24%) in the English version were shown to have the misuse of statistical terms with statistically significant difference (P = .01). Conclusion: Some of the articles in the JKAP had inadequate statistical validity, given the statistical errors identified in this assessment. Hence, dental researchers should be more careful when it comes to describing and applying statistical methods.

Trend Analysis of Barrier-free Academic Research using Text Mining and CONCOR (텍스트 마이닝과 CONCOR을 활용한 배리어 프리 학술연구 동향 분석)

  • Jeong-Ki Lee;Ki-Hyok Youn
    • Journal of Internet of Things and Convergence
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    • v.9 no.2
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    • pp.19-31
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    • 2023
  • The importance of barrier free is being highlighted worldwide. This study attempted to identify barrier-free research trends using text mining. Through this, it was intended to help with research and policies to create a barrier free environment. The analysis data is 227 papers published in domestic academic journals from 1996 when barrier free research began to 2022. The researcher converted the title, keywords, and abstract of an academic thesis into text, and then analyzed the pattern of the thesis and the meaning of the data. The summary of the research results is as follows. First, barrier-free research began to increase after 2009, with an annual average of 17.1 papers being published. This is related to the implementation guidelines for the barrier-free certification system that took effect on July 15, 2008. Second, results of barrier-free text mining i) As a result of word frequency analysis of top keywords, important keywords such as barrier free, disabled, design, universal design, access, elderly, certification, improvement, evaluation, and space, facility, and environment were searched. ii) As a result of TD-IDF analysis, the main keywords were universal design, design, certification, house, access, elderly, installation, disabled, park, evaluation, architecture, and space. iii) As a result of N-Ggam analysis, barrier free+certification, barrier free+design, barrier free+barrier free, elderly+disabled, disabled+elderly, disabled+convenience facilities, the disabled+the elderly, society+the elderly, convenience facilities+installation, certification+evaluation index, physical+environment, life+quality, etc. appeared in a related language. Third, as a result of the CONCOR analysis, cluster 1 was barrier-free issues and challenges, cluster 2 was universal design and space utilization, cluster 3 was Improving Accessibility for the Disabled, and cluster 4 was barrier free certification and evaluation. Based on the analysis results, this study presented policy implications for vitalizing barrier-free research and establishing a desirable barrier free environment.

물리.화학적 방법에 의한 참돔(Pagrus major)의 품질판정에 관한 연구

  • 김태진;배진한;심길보;여해경;정호진;조영제
    • Proceedings of the Korean Aquaculture Society Conference
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    • 2003.10a
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    • pp.155-156
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    • 2003
  • 우리나라는 해방 후 어려웠던 경제난국에서 벗어나 산업발전기에 접어들면서 수산물보다는 식탁에서 육류의 섭취가 상대적으로 많이 증가되었다. 그러나 최근에 들어와서는 외식산업의 현저한 발달과 더불어 즉석편리식품이나 육류의 소비가 증가함에 따라 비만, 동맥경화 및 영양의 과잉공급에 따른 각종 성인병이 만연하고 있는 실정이단, 이러한 시점에 수산물이 가지고 있는 건강기능성이나 생리효과가 식품관련 연구자들에 의해 밝혀지면서 생선회가 건강지향성과 기호성이라는 측면에서 두 가지 조건 모두를 만족시키는 식품으로 자리잡아 외식산업의 한 축을 이루어 생선회의 소비는 급증하고 있으나, 자연산 활어는 남획에 따른 자원고갈 및 어장축소 등 여러 가지 이유로 현재 유통되고 있는 생선회의 90% 이상은 양식산 활어이며, 양식 활어의 생산량 또한 1980년대 후반에 비하여 10배 이상 증가되어 있을 뿐만 아니라 가까운 중국이나 일본 등지에서 생선회로 먹기 위하여 많은 량의 활어가 수입되고 있는 실정이다 이렇게 생산된 활어는 활어시장에서 활어의 품질에 관계없이 중량을 기준으로 거래되고 있어 여러 가지 문제를 야기시킬 수 있다. 그러므로, 활어 품질판정 기술의 개발은 우리나라 양식업의 대외경쟁력을 갖추게 할 뿐만 아니라 어민소득을 향상시킬 수 있다. 또한 활어의 유통 질서를 갖추기 위해서 양식활어 근육의 품질을 정확하고도 신속하게 판정할 수 있는 기술을 개발하고자 하였다. 그러므로, 육질의 판정을 위한 기초자료로써 사육수조에서 운동여부와 운동횟수에 의한 양식 활어의 품질을 비교 검토하였다. 운동사육구(2회/1일, 0.5m/s)와 비운동사육구의 초기수분함량은 각각 73.44±0.87%, 72.88±0.25%의 함량이였다. 운동사육시간이 길어질수록 운동사육구에서는 수분함량이 운동5일째에는 73.56±0.22%였으며, 운동 20일에는 75.88±0.94%로 초기수분함량보다는 3%정도 증가하였다. 반면, 비운동사육구에서는 큰 변화를 나타내고 있지 않았다(p<0.05). 운동과 비운동시킨 참돔의 지질 함량의 변화는 운동시킨 참돔은 운동으로 인한 에너지 소비로 인하여 함량이 유의적으로 감소했으며(r=-0.35), 비운동사육구에서는 절식으로 인하여 지질함량이 감소하였다(r=-0.38). 파괴강도와 가장 밀접한 영향을 가지는 콜라겐은 운동과 비운동 모두 사육기간동안 큰 변화는 보이지 않았다. 초기의 파괴강도값은 1.45±0.02kg(운동사육구), 1.36±0.18kg(비운동사육구)이였으며 사육기간동안 운동사육구는 파괴강도값이 증가한 반면, 비운동수조에서는 참돔의 파괴강도는 사육기간동안 큰 유의차가 없었다. 각 성분간의 상관도를 살펴보면, 수분함량과 파괴강도는 상관성을 가졌으며, 지질함량과 파괴강도도 같은 경향은 나타내었다. 운동기간동안의 파괴강도와 콜라겐 사이에는 상관성의 거의 없었다. 이는 운동기간에 따른 파괴강도의 증가가 콜라겐의 함량의 증가보다는 지질함량의 감소와 수분함량의 증가와 같은 성분과의 상관성이 크다고 판단된다. 다음으로는, 운동횟수에 의한 영향으로써 운동시간을 1일 6시간으로 설정하여, 운동횟수를 결정하기 위하여 오전, 오후에 각 3시간씩 운동시키는 방법과 오전부터 6시간동안 운동시키는 두 방법을 이용하여 품질을 비교하였다. 각 조건에 따라 운동시킨 참돔의 수분함량을 나타낸 것으로, 2회(오전 3시간, 오후 3시간)에 나누어서 운동시키기 위한 육의 수분함량은 73.37±2.02%를 나타냈으며, 1회(6시간 운동)운동시키기 위한 육은 71.74±1.66%을 나타내었다. 각각의 운동조건에서 양식된 참돔은 사육초기에는 큰 변화가 없었으나, 사육 5일 이후에는 수분함량이 증가하여 15일에는 76.40±0.14, 75.62±0.98%의 수분함량을 2회와 1회 운동시킨 참돔의 육에서 각각 나타났다. 운동횟수에 따른 지질함량은 2회 운동시킨 참돔은 5.83±2.08, 1회 운동시킨 참돔은 6.72±1.84%을 나타났으며, 사육기간이 증가할수록 함량은 감소하였다. 하루 1회운동시킨 참돔은 지질 함량의 감소율이 2회 운동시킨 참돔보다는 작았지만, 1회 운동시킨 참돔과 마찬가지로 운동기간동안 지질은 감소하였다. 운동횟수와 상관없이 운동기간동안 콜라겐의 함량은 큰 증가를 보이지 않았다. 파괴강도값은 운동횟수가 많을수록 증가하는 경향을 나타내었다. 운동시킨 참돔은 운동횟수에 상관없이 지질 함량이 감소할수록 파괴강도값이 증가하였으며, 운동횟수가 하루 2회인 참돔에서는 지질함량과 파괴강도값이 높은 상관관계를 나타내고 있다(p<0.05, r=0.866(2회/1일). 운동기간과 파괴강도의 값, 운동기간과 수분함량, 운동기간과 지질함량간의 상관성은 운동횟수에 상관없이 높은 상관관계를 나타냈다. 또한, 콜라겐함량은 운동기간과 상관관계 없이 상관성이 낮았다. 그러므로, 본 실험의 목적인 양식산 활어의 품질판정을 하기 위한 요인으로 동일 어종에는 콜라겐보다는 파괴강도, 수분함량 및 지질함량과의 관계를 상관성을 가지므로, 양식 활어의 품질판정 요인으로 선정하였다.

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A Literature Review and Classification of Recommender Systems on Academic Journals (추천시스템관련 학술논문 분석 및 분류)

  • Park, Deuk-Hee;Kim, Hyea-Kyeong;Choi, Il-Young;Kim, Jae-Kyeong
    • Journal of Intelligence and Information Systems
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    • v.17 no.1
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    • pp.139-152
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    • 2011
  • Recommender systems have become an important research field since the emergence of the first paper on collaborative filtering in the mid-1990s. In general, recommender systems are defined as the supporting systems which help users to find information, products, or services (such as books, movies, music, digital products, web sites, and TV programs) by aggregating and analyzing suggestions from other users, which mean reviews from various authorities, and user attributes. However, as academic researches on recommender systems have increased significantly over the last ten years, more researches are required to be applicable in the real world situation. Because research field on recommender systems is still wide and less mature than other research fields. Accordingly, the existing articles on recommender systems need to be reviewed toward the next generation of recommender systems. However, it would be not easy to confine the recommender system researches to specific disciplines, considering the nature of the recommender system researches. So, we reviewed all articles on recommender systems from 37 journals which were published from 2001 to 2010. The 37 journals are selected from top 125 journals of the MIS Journal Rankings. Also, the literature search was based on the descriptors "Recommender system", "Recommendation system", "Personalization system", "Collaborative filtering" and "Contents filtering". The full text of each article was reviewed to eliminate the article that was not actually related to recommender systems. Many of articles were excluded because the articles such as Conference papers, master's and doctoral dissertations, textbook, unpublished working papers, non-English publication papers and news were unfit for our research. We classified articles by year of publication, journals, recommendation fields, and data mining techniques. The recommendation fields and data mining techniques of 187 articles are reviewed and classified into eight recommendation fields (book, document, image, movie, music, shopping, TV program, and others) and eight data mining techniques (association rule, clustering, decision tree, k-nearest neighbor, link analysis, neural network, regression, and other heuristic methods). The results represented in this paper have several significant implications. First, based on previous publication rates, the interest in the recommender system related research will grow significantly in the future. Second, 49 articles are related to movie recommendation whereas image and TV program recommendation are identified in only 6 articles. This result has been caused by the easy use of MovieLens data set. So, it is necessary to prepare data set of other fields. Third, recently social network analysis has been used in the various applications. However studies on recommender systems using social network analysis are deficient. Henceforth, we expect that new recommendation approaches using social network analysis will be developed in the recommender systems. So, it will be an interesting and further research area to evaluate the recommendation system researches using social method analysis. This result provides trend of recommender system researches by examining the published literature, and provides practitioners and researchers with insight and future direction on recommender systems. We hope that this research helps anyone who is interested in recommender systems research to gain insight for future research.

Are Bound Residues a Solution for Soil Decontamination\ulcorner

  • Bollag, Jean-Marc
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.10a
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    • pp.111-124
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    • 2003
  • Processes that cause immobilization of contaminants in soil are of great environmental importance because they may lead to a considerable reduction in the bioavailability of contaminants and they may restrict their leaching into groundwater. Previous investigations demonstrated that pollutants can be bound to soil constituents by either chemical or physical interactions. From an environmental point of view, chemical interactions are preferred, because they frequently lead to the formation of strong covalent bonds that are difficult to disrupt by microbial activity or chemical treatments. Humic substances resulting from lignin decomposition appear to be the major binding ligands involved in the incorporation of contaminants into the soil matrix through stable chemical linkages. Chemical bonds may be formed through oxidative coupling reactions catalyzed either biologically by polyphenol oxidases and peroxidases, or abiotically by certain clays and metal oxides. These naturally occurring processes are believed to result in the detoxification of contaminants. While indigenous enzymes are usually not likely to provide satisfactory decontamination of polluted sites, amending soil with enzymes derived from specific microbial cultures or plant materials may enhance incorporation processes. The catalytic effect of enzymes was evaluated by determining the extent of contaminants binding to humic material, and - whenever possible - by structural analyses of the resulting complexes. Previous research on xenobiotic immobilization was mostly based on the application of $^{14}$ C-labeled contaminants and radiocounting. Several recent studies demonstrated, however, that the evaluation of binding can be better achieved by applying $^{13}$ C-, $^{15}$ N- or $^{19}$ F-labeled xenobiotics in combination with $^{13}$ C-, $^{15}$ N- or $^{19}$ F-NMR spectroscopy. The rationale behind the NMR approach was that any binding-related modification in the initial arrangement of the labeled atoms automatically induced changes in the position of the corresponding signals in the NMR spectra. The delocalization of the signals exhibited a high degree of specificity, indicating whether or not covalent binding had occurred and, if so, what type of covalent bond had been formed. The results obtained confirmed the view that binding of contaminants to soil organic matter has important environmental consequences. In particular, now it is more evident than ever that as a result of binding, (a) the amount of contaminants available to interact with the biota is reduced; (b) the complexed products are less toxic than their parent compounds; and (c) groundwater pollution is reduced because of restricted contaminant mobility.

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Market Segmentation of Converging New Media Advertising: The Interpretative Approach Based on Consumer Subjectivity (융합형 뉴미디어 광고의 시장세분화 연구: 소비자 주관성에 근거한 해석적 관점에서)

  • Seo, Kyoung-Jin;Hwang, Jin-Ha;Jeung, Jang-Hun;Kim, Ki-Youn
    • Journal of Internet Computing and Services
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    • v.15 no.4
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    • pp.91-102
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    • 2014
  • The purpose of this research is to perform the consumer typological study of integrated emerging digital advertisement, where IT and advertisement industry were fused, and to propose the theoretical definition about consumer characteristic which is in need for collection of related market subdivision strategy in perspective of business marketing. For this, the Q methodology, the 'subjectivity' research of qualitative perspective, which discovers new theory by interpreting subjective system of thinking, preference, opinion, and recognition of inner side of respondents, was applied and analyzed. Compared to previous quantitative research that pursues hypothesis verification, this Q methodology is not dependent on operational definition proposed by researcher but pursues for analytic study completely reflecting objective testimony of respondents. For this reason, Q study analyzes in-depth the actual consumer type, which can be found at the initial market formation stage of new service, therefore this study is applicable for theorizing the consumer character as a mean of advanced research. This study extracted thirty 'IT integrated digital advertisement type (Q sample)' from thorough literature research and interviews, and eventually discovered a total four consumer types from analyzing each Q sorting research data of 40 respondents (P sample). Moreover, by interpreting subdivided intrinsic characteristic of each group, the four types were named as 'multi-channel digital advertisement pursuit type', 'emotional advertisement pursuit type', 'new media advertisement pursuit type', and Web 2.0 advertisement pursuit type'. The analysis result of this study is being expected for its value of usage as advanced research of academic and industrial research with the emerging digital advertisement industry as a subject, and as basic research in the field of R&D, Marketing program and the field of designing the advertisement creative strategy and related policy.

Quality Control of Agro-meteorological Data Measured at Suwon Weather Station of Korea Meteorological Administration (기상청 수원기상대 농업기상 관측요소의 품질관리)

  • Oh, Gyu-Lim;Lee, Seung-Jae;Choi, Byoung-Choel;Kim, Joon;Kim, Kyu-Rang;Choi, Sung-Won;Lee, Byong-Lyol
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.17 no.1
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    • pp.25-34
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    • 2015
  • In this research, we applied a procedure of quality control (QC) to the agro-meteorological data measured at the Suwon weather station of Korea Meteorological Administration (KMA). The QC was conducted through six steps based on the KMA Real-time Quality control system for Meteorological Observation Data (RQMOD) and four steps based on the International Soil Moisture Network (ISMN) QC modules. In addition, we set up our own empirical method to remove erroneous data which could not be filtered by the RQMOD and ISMN methods. After all these QC procedures, a well-refined agro-meteorological dataset was complied at both air and soil temperatures. Our research suggests that soil moisture requires more detailed and reliable grounds to remove doubtful data, especially in winter with its abnormal variations. The raw data and the data after QC are now available at the NCAM website (http://ncam.kr/page/req/agri_weather.php).

Impact Resistance Reliability of Sn-1.2Ag-0.5Cu-0.4In Solder Joints (Sn-1.2Ag-0.5Cu-0.4In 조성 솔더 접합부의 내 충격 신뢰성 평가)

  • Yu, A-Mi;Lee, Chang-Woo;Kim, Jeong-Han;Kim, Mok-Soon;Lee, Jong-Hyun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.226-226
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    • 2008
  • 지난 10여년 동안 Sn-3.0Ag-0.5(wt%)Cu 합금은 대표 무연솔더 조성으로 다양한 전자제품의 실장 및 접합에 적용되어 왔으며, 그 신뢰성 역시 충분히 검증된 바 있다. 그러나 최근 Ag 가격의 급격한 상승과 솔더 접합부의 내 충격 신뢰성을 보다 향상시키고자 하는 업계의 동향은 Ag의 함량이 낮은 무연솔더 조성의 적용 확대를 유도하고 있다. 이에 따라 본 연구자들은 저 Ag 함유 무연슬더로 Sn-1.2Ag-0.5Cu-0.4In 조성을 제안한 바 있는데, 이는 Sn-3.0Ag-0.5Cu 조성 이상의 solderability를 가지면서도 그 금속원료 가격이 약 20% 가량 저렴한 특징을 가진다. 또한 열 싸이클링 (cycling) 테스트를 통한 슬더 조인트의 신뢰성을 평가한 결과, Sn-3.0Ag-0.5Cu에 크게 뒤떨어지지 않는 양호한 특성이 관찰되었다. 따라서 본 연구에서는 열 싸이클링 테스트와 더불어 최근 그 중요성이 지속적으로 커지고 있는 내 충격 신뢰성 평가 시험을 실시하여 개발된 4원계 무연솔더 조성의 기계적 특성을 기존 무연솔더 조성과 비교, 분석해 보았다. 각 솔더 조성은 솔더 볼 형태로 제조되어 CSP(Chip Scale Package) 상에 범핑 (bumping)되었으며, CSP를 PCB(Printed Circuit Board) 상에 실장하는 공정에서도 Sn-3.0Ag-0.5Cu 및 Sn-1.2Ag-0.5Cu-0.4In의 두 종류의 솔더 페이스트가 사용되었다. 본 연구에서의 내 충격 신뢰성 시험에는 자체 제작한 rod drop 시험기를 사용하였는데, 고정된 CSP 실장 board의 후면 부위를 일정한 높이에서 추를 반복적으로 자유 낙하시켜 급격한 충격을 주는 방식으로 실험을 실시하였다. 이 때 추의 무게는 30g, 낙하 높이는 10cm 였으며, 추의 낙하 시 측정된 board 의 휨 변위량은 약 0.7mm로 측정되었다. 사용된 CSP와 PCB 는 모두 daisy chain 방식으로 연결되어 있기 때문에 저항측정기를 사용한 간단한 실시간 저항 측정 방법으로 시험 이력에 따른 파단부의 발생 시점과 대략의 위치를 손쉽게 확인할 수 있었다. 솔더 조인트의 파단 기준 저항값으로 $1000\Omega$을 설정하였으며. 각 조건 당 5 개 이상의 샘플에 대해 평가를 실시한 후 그 평균값을 조사하였다. 시험 결과 제안된 Sn-1.2Ag-0.5Cu-0.4In 조성은 대표적인 저 Ag 함유 조성인 Sn-1.0Ag-0.5Cu에 비해서는 떨어지는 내 충격 신뢰성을 나타내었지만, 우수한 연성에 기인하여 Sn-3.0Ag-0.5Cu 조성에 비해서는 약 2 배 이상 우수한 신뢰성이 관찰되었다. 또한 CSP의 실장 시 Sn-3.0Ag-0.5Cu보다 Sn-1.2Ag-0.5Cu-0.4In 조성 솔더 페이스트를 적용한 경우에서 보다 우수한 내 충격 신뢰성을 나타내어 기본적으로 개발된 Sn-1.2Ag-0.5Cu-0.4In 솔더 페이스트가 Sn-3.0Ag-0.5Cu 조성의 기존 솔더 페이스트 보다 내 충격 신뢰성이 우수함을 검증할 수 있었다. 각 조성의 솔더 조인트를 $150^{\circ}C$ 에서 500시간 aging한 후 실시한 내 충격 신뢰성 평가에서는 모든 조성에서 그 신뢰성이 급감하는 경항을 나타내었으나, Sn-1.2Ag-0.5Cu-0.4In가 Sn-l.0Ag-0.5Cu보다도 그 상대적인 신뢰성이 우수한 것으로 관찰되었다. 이와 같이 aging 후 실시하는 충격시험은 가장 실제적인 상황과 유사한 조건이므로 상기의 실험 결과는 매우 고무적이었으며, 이에 대한 보다 면밀한 분석이 요청되었다. 마지막으로 파면 및 미세조직 관찰을 통하여 각 조성에서의 충격 파단 특성을 비교, 분석해 보았다.

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Research Trend and Futuristic Guideline of Platform-Based Business in Korea (플랫폼 기반 비즈니스에 대한 국내 연구동향 및 미래를 위한 가이드라인)

  • Namn, Su Hyeon
    • Management & Information Systems Review
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    • v.39 no.1
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    • pp.93-114
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    • 2020
  • Platform is considered as an alternative strategy to the traditional linear pipeline based business. Moreover, in the 4th industrial revolution period, efficiency driven pipeline business model needs to be changed to platform business. We have such success stories about platform as Apple, Google, Amazon, Uber, and so on. However, for those smaller corporations, it is not easy to find out the transformation strategy. The essence of platform business is to leverage network effect in management. Thus platform based management can be rephrased as network management across the business functions. Research on platform business is popular and related to diverse facets. But few scholars cover what the research trend of the domain is. The main purpose of this paper is to identify the research trend on platform business in Korea. To do that we first propose the analytical model for platform architecture whose components are consumers, suppliers, artifacts, and IT platform system. We conjecture that mapping of the research work on platform to the components of the model will make us understand the hidden domain of platform research. We propose three hypotheses regarding the characteristics of research and one proposition for the transitional path from pipeline to platform business model. The mapping is based on the research articles filtered from the Korea Citation Index, using keyword search. Research papers are searched through the keywords provided by authors using the word of "platform". The filtered articles are summarized in terms of the attributes such as major component of platform considered, platform type, main purpose of the research, and research method. Using the filtered data, we test the hypotheses in exploratory ways. The contribution of our research is as follows: First, based on the findings, scholars can find the areas of research on the domain: areas where research has been matured and territory where future research is actively sought. Second, the proposition provided can give business practitioners the guideline for changing their strategy from pipeline to platform oriented. This research needs to be considered as exploratory not inferential since subjective judgments are involved in data collection, classification, and interpretation of research articles.