• Title/Summary/Keyword: history of science and technology

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SVM-Based Incremental Learning Algorithm for Large-Scale Data Stream in Cloud Computing

  • Wang, Ning;Yang, Yang;Feng, Liyuan;Mi, Zhenqiang;Meng, Kun;Ji, Qing
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.10
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    • pp.3378-3393
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    • 2014
  • We have witnessed the rapid development of information technology in recent years. One of the key phenomena is the fast, near-exponential increase of data. Consequently, most of the traditional data classification methods fail to meet the dynamic and real-time demands of today's data processing and analyzing needs--especially for continuous data streams. This paper proposes an improved incremental learning algorithm for a large-scale data stream, which is based on SVM (Support Vector Machine) and is named DS-IILS. The DS-IILS takes the load condition of the entire system and the node performance into consideration to improve efficiency. The threshold of the distance to the optimal separating hyperplane is given in the DS-IILS algorithm. The samples of the history sample set and the incremental sample set that are within the scope of the threshold are all reserved. These reserved samples are treated as the training sample set. To design a more accurate classifier, the effects of the data volumes of the history sample set and the incremental sample set are handled by weighted processing. Finally, the algorithm is implemented in a cloud computing system and is applied to study user behaviors. The results of the experiment are provided and compared with other incremental learning algorithms. The results show that the DS-IILS can improve training efficiency and guarantee relatively high classification accuracy at the same time, which is consistent with the theoretical analysis.

Chemical sensors technology (화학 센서 기술)

  • Lee, Duk-Dong
    • Journal of Sensor Science and Technology
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    • v.18 no.1
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    • pp.1-21
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    • 2009
  • There have been continued effects to develop various types of chemical sensors according to the demands in many application fields such as safety, pollution, environment, medical engineering and food industries etc. In this review, the author intended to cover the general aspects of chemical sensors, including the history of the development, the classification, the sensing properties, and the types and application examples. And the future outlook of the chemical sensor technology, focusing on the advanced materials, high technology fusion, miniaturized intelligent system and ubiquitous sensor networks etc., has been described.

Reduced record method for efficient time history dynamic analysis and optimal design

  • Kaveh, A.;Aghakouchak, A.A.;Zakian, P.
    • Earthquakes and Structures
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    • v.8 no.3
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    • pp.639-663
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    • 2015
  • Time history dynamic structural analysis is a time consuming procedure when used for large-scale structures or iterative analysis in structural optimization. This article proposes a new methodology for approximate prediction of extremum point of the response history via wavelets. The method changes original record into a reduced record, decreasing the computational time of the analysis. This reduced record can be utilized in iterative structural dynamic analysis of optimization and hence significantly reduces the overall computational effort. Design examples are included to demonstrate the capability and efficiency of the Reduced Record Method (RRM) when utilized in optimal design of frame structures using meta-heuristic algorithms.

조선시대의 산학서에 관하여

  • 이창구
    • Journal for History of Mathematics
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    • v.11 no.1
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    • pp.1-9
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    • 1998
  • This article explores what is the genuine Koreanness in Korean arithmetic by examining what kind of influence the Chinese arithmetic had on the Korean arithmetic and how the Korean arithmetic scholars had accepted and utilized it. Because the main stream of Korean culture before the end of Chosun dynasty was located under the umbrella of the Chinese philosophy, technique, and culture, it is necessary to make researches on the historical documents and materials in order to establish the milestone in the Korean arithmetic history for the Korean arithmetic scholars. For this research, the arithmetic books published in between the sixteenth century and the end of Chosun dynasty are mainly consulted and discussed, dealing with the bibliographical introduction in the arithmetic Part in Re Outline History of the Korean Science & Technology written by Prof. Yong-Woon Kim.

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A MATHEMATICAL MODEL FOR HISTORY-BASED ACCESS CONTROL

  • Kim, Hee-Young
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.8 no.1
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    • pp.11-30
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    • 2004
  • Access Control is one of essential branches to provide system's security. Depending on what standards we apply, in general, there are Role-based access control, History-based access control. The first is based on subject's role, The later is based on subject's history. In fact, RBAC has been implemented, we are using it by purchasing some orders through the internet. But, HBAC is so complex that there will occur some errors on the system. This is more and more when HBAC is used with other access controls. So HBAC's formalization and model which are general enough to encompass a range of policies in using more than one access control model within a given system are important. To simplify these, we design the mathematical model called non-access structure. This Non-access structure contains to historical access list. If it is given subjects and objects, we look into subject grouping and object relation, and then we design Non-access structure. Then we can determine the permission based on history without conflict.

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A Branch Predictor with New Recovery Mechanism in ILP Processors for Agriculture Information Technology (농업정보기술을 위한 ILP 프로세서에서 새로운 복구 메커니즘 적용 분기예측기)

  • Ko, Kwang Hyun;Cho, Young Il
    • Agribusiness and Information Management
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    • v.1 no.2
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    • pp.43-60
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    • 2009
  • To improve the performance of wide-issue superscalar processors, it is essential to increase the width of instruction fetch and the issue rate. Removal of control hazard has been put forward as a significant new source of instruction-level parallelism for superscalar processors and the conditional branch prediction is an important technique for improving processor performance. Branch mispredictions, however, waste a large number of cycles, inhibit out-of-order execution, and waste electric power on mis-speculated instructions. Hence, the branch predictor with higher accuracy is necessary for good processor performance. In global-history-based predictors like gshare and GAg, many mispredictions come from commit update of the branch history. Some works on this subject have discussed the need for speculative update of the history and recovery mechanisms for branch mispredictions. In this paper, we present a new mechanism for recovering the branch history after a misprediction. The proposed mechanism adds an age_counter to the original predictor and doubles the size of the branch history register. The age_counter counts the number of outstanding branches and uses it to recover the branch history register. Simulation results on the SimpleScalar 3.0/PISA tool set and the SPECINT95 benchmarks show that gshare and GAg with the proposed recovery mechanism improved the average prediction accuracy by 2.14% and 9.21%, respectively and the average IPC by 8.75% and 18.08%, respectively over the original predictor.

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Contribution of Journals to Academic Disciplines

  • Lee, Hye-Young
    • Journal of Information Science Theory and Practice
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    • v.3 no.1
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    • pp.66-76
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    • 2015
  • This research uses a new approach to analyze the extent of influence journal papers have on the progress of varied research fields by estimation of subject-based influence on research other than impact factor that relies on citation index. It is initiated with the hypothesis that earlier established citation relations between journal and citing paper, which reveals the research field that contains the highest citation index and hence has received the greatest contribution from a particular journal, would have inconsistent contribution to the research field over the year of journal publication. The target research is primarily 128 journal papers and 4,123 citing papers from Information Systems Research published in the years 2001, 2004, 2007, and 2010. The characteristics of citation history and hallmarks of research field of citing papers were studied and analysis on significant distinction between citing fields based on the year of publication was performed. The analysis results show the order of citation rate to be highest from Computer Science (2,221 cases), Business & Economics (2,191 cases), and Information Science & Library Science (1,901 cases). The citation history of the journal, nonetheless, indicates increase in citation during 2-3 years after the earliest publication till it achieves constant citation. The statistical analysis shows significant variation in citing fields in accordance with the publication year; especially in 2010, journal contribution has increased in the fields of Business & Economics, Operations Research & Management Science, and Health Care Sciences & Services but, however, is reduced in Education & Educational Research and Social Sciences - Other Topics.

Development of Risk-Appearance Frequency Evaluation Model for Railway Level-Crossing Accidents (철도건널목 사고 위험도-발생빈도 평가모델 개발)

  • Kim, Min-Su;Wang, Jong-Bae;Park, Chan-Woo;Choi, Don-Bum
    • Journal of the Korean Society of Safety
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    • v.24 no.3
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    • pp.96-101
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    • 2009
  • In this study, a risk-appearance frequency evaluation model for railway level-crossing accidents is developed with the frequency estimation based on the accident history. It follows the worldwide common safety management approach and reflects the operation conditions and accident properties of the domestic railway system. The risk appearance frequency evaluation process contains a development of accident scenarios by defining the system configurations and functions, and a frequency estimation of hazardous events based on the accident history. The developed model is verified with the accident history during 5 years('03-'07) for 3 hazardous events: 'Being trapped in level crossing(Hl)', 'Crossing during warning signal(H2)' and 'Breaking through/detouring the barrier(H3)'. This risk appearance frequency evaluation model will be combined with a consequence evaluation model so as to offer full risk assessment for the railway accident. The accident risk assessment will contribute to improving the safety management of the railway system.

A Pilot Study on Lee Gyu-Jun(李圭晙)'s Life and Thoughts (이규준(李圭晙)의 생애(生涯)와 사상적(思想的) 경향(傾向))

  • Kwon, Oh-mi;Park, Sang-young;Ahn, Sang-young;Han, Chang-huyn;Ahn, Sang-woo
    • The Journal of Korean Medical History
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    • v.22 no.1
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    • pp.7-13
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    • 2009
  • This article conducted an pilot study on Lee Gyu-Jun(李圭晙)'s life and thoughts. He championed, and is mainly based on, old annotations of ancient Confucian bibles古文 that were made in the Han漢 and Tang唐 era in Chinese history and consequently took additionally into account Zuxi朱熹's annotations on Confucian bibles. This cause big trouble to him in conservative Gyeong Shang Province(嶺南). He participated in the Confucian Religion Movement孔敎運動 and proposed constitutional monarchy as a new polity fit for changing Korean history. He closely interacted with many resistants to the Japanese rule of Korea and had a mixed perspective on Western culture, science and technology, and social system, positive or negative, contingent on cases. He made great footprints in the history of both modern Korean medicine and philosophy. Thus there is an urgent need for the overall study on Lee Gyu-Jun in every aspect.

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Survey of Temporal Information Extraction

  • Lim, Chae-Gyun;Jeong, Young-Seob;Choi, Ho-Jin
    • Journal of Information Processing Systems
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    • v.15 no.4
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    • pp.931-956
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    • 2019
  • Documents contain information that can be used for various applications, such as question answering (QA) system, information retrieval (IR) system, and recommendation system. To use the information, it is necessary to develop a method of extracting such information from the documents written in a form of natural language. There are several kinds of the information (e.g., temporal information, spatial information, semantic role information), where different kinds of information will be extracted with different methods. In this paper, the existing studies about the methods of extracting the temporal information are reported and several related issues are discussed. The issues are about the task boundary of the temporal information extraction, the history of the annotation languages and shared tasks, the research issues, the applications using the temporal information, and evaluation metrics. Although the history of the tasks of temporal information extraction is not long, there have been many studies that tried various methods. This paper gives which approach is known to be the better way of extracting a particular part of the temporal information, and also provides a future research direction.