• Title/Summary/Keyword: T-search

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A Study of the Behavioral Characteristics of the Primary and Secondary Searches on Online Databases (온라인 데이터베이스의 1차탐색과 2차탐색의 특성 연구)

  • Noh Dong-Jo
    • Journal of the Korean Society for Library and Information Science
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    • v.32 no.2
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    • pp.189-209
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    • 1998
  • The purpose of this study is to verify the difference of behavioral characteristics between the primary and secondary search, the influence of the primary search results on Online databases. Data is collected by surveying the professional and end-user searchers in 33 online information service centers. 262 valid responses out of 308 questionaire are analyzed by the t-test, ANOVA, $\chi^2-test$ using SAS program. The major findings are as follows : (1) Preparatory searches(the levels of expectation, the degree of question comprehension), search results(the number of output documents, precision ratio, recall ratio, degree of satisfaction) are significantly different between the primary and secondary searches on Online Databases. But the number of search terms, Boolean logics, files, systems, relevant documents are not significantly different between the primary and secondary searches. (2) The results of the primary search affect the secondary searches. The number of output documents in the primary search affect the modification of search strategies and objects in the secondary searches. The number of relevant documents affect the variation of search scopes in the secondary searches. The precision ratio affect the change of search strategies and scopes in the secondary searches.

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Performance Evaluation of Initial Cell Search Scheme Using Time Tracker for W-CDMA (시간 동기 블록을 적용한 비동기 W-CDMA용 초기 셀 탐색 방법의 성능 분석)

  • Hwang, Sang-Yun;Kang, Bub-Ju;Choi, Woo-Young;Kim, Jae-Seok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.1B
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    • pp.24-33
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    • 2002
  • The cell search scheme for W-CDMA consists of the following three stages: slot synchronization(1st stage), group identification and frame boundary detection(2nd stage), and long code identification(3rd stage). The performance of the cell search when a mobile station is switched on, which is referred to as initial cell search, is decreased by the initial frequency and timing error. In this paper, we propose the pipeline structured initial cell search scheme using time trackers to compensate for the impact of the initial timing error in the stage 2 and stage 3. The simulation results show that the performance of the proposed scheme is maximal 1.5dB better than that of the conventional one when the initial timing error is near ${\pm}T_c$/2.

Educational Needs for Employment Competency of College Students in Management Using IPA Technique

  • Kang, Kyoung-Yeoun
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.11
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    • pp.219-228
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    • 2020
  • The purpose of this study is to analysis the educational needs for employment competency of college students in management. For this purpose, a survey about importance and retention level of employment competency was administered to 215 students at A college in Chungcheong between December 2 and 6, 2019. The difference between importance and retention level was analyzed through the corresponding sample t-test, and the educational needs was confirmed through the IPA technique. The results of Study were as follows: 'major knowledge capabilities' was found to be in the high priority of educational needs in all students.; male showed high-priority needs for 'information search, foreign language utilization' and female showed high-priority needs for 'information search, setting employment goals'; 'information search' was ranked as priority educational needs in all grades, it was necessary to add 'information search', 'foreign language utilization', 'fill out the necessary documents for job search' for 1 grade and 'Self-understanding', 'foreign language utilization' for 4 grade. The findings of this study may produce data useful for designing the employment support program for college students in management.

Time and Space Efficient Search with Suffix Arrays (접미사 배열을 이용한 시간과 공간 효율적인 검색)

  • Choi, Yong-Wook;Sim, Jeong-Seop;Park, Kun-Soo
    • Journal of KIISE:Computer Systems and Theory
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    • v.32 no.5
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    • pp.260-267
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    • 2005
  • To search efficiently a text T of length n for a pattern P over an alphabet 5, suffix trees and suffix arrays are widely used. In case of a large text, suffix arrays are preferred to suffix trees because suffix ways take less space than suffix trees. Recently, O(${\mid}P{\mid}{\codt}{\mid}{\Sigma}{\mid}$-time and O(${\mid}P{\mid}P{\cdot}log{\mid}{\Sigma}{\mid}$)-time search algorithms in suffix ways were developed. In this paper we present time and space efficient search algorithms in suffix arrays. One algorithm runs in O(${\mid}P{\mid}$) time using O($n{\cdot}{\mid}{\Sigma}{\mid}$)-bits space, and the other runs in O($n{\cdot}{\mid}{\Sigma}{\mid}$ time using O($nlog{\mid}{\Sigma}{\mid}+{\mid}{\Sigma}{\mid}{\cdot}$nlog log n/logn)-bits space, which is more space efficient and still fast. Experiments show that our algorithms are efficient in both time and space when compared to previous algorithms.

Controller Design for Affine T-S Fuzzy System with Parametric Uncertainties (파라미터 불확실성을 갖는 어핀 T-S 퍼지 시스템의 제어기 설계)

  • Lee, Sang-In;Park, Jin-Bae;Joo, Young-Hoon
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2004.04a
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    • pp.133-136
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    • 2004
  • This paper proposes a stability condition in affine Takagi-Sugeno (T-S) fuzzy systems with parametric uncertainties and then, introduces the design method of a fuzzy-model-based controller which guarantees the stability. The analysis is based on Lyapunov functions that are continuous and piecewise quadratic. The search for a piecewise quadratic Lyapunov function can be represented in terms of linear matrix inequalities (LMIs).

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The Search of Image Outline Using 3D Viewpoint Change (3차원 시점 변화를 활용한 이미지 외곽라인 검색 제안)

  • Kim, Sungkon
    • The Journal of the Convergence on Culture Technology
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    • v.5 no.3
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    • pp.283-288
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    • 2019
  • We propose a method to search for similar images by using outline lines and viewpoints. In the first test, the three-dimensional image, which can't control the motion, has lower search accuracy than the static flat image. For the cause analysis, six specific tropical fish data were selected. We made a 3D graphics of tropical fishes of each kind, and we made 144 image outline lines with 12 stage viewpoints of top, bottom, left and right. Tropical fish by type were collected and sorted by time of search through similar search. Studies have shown that there are many unique viewpoints for each species of tropical fish. To increase the accuracy of the search, a User Interface was created to select the user's point of view. When the user selects the viewpoint of the image, a method of showing the result in consideration of the range of the related viewpoint is proposed.

Efficiency Improvement of the Fixed-Complexity Sphere Decoder

  • Mohaisen, Manar;Chang, Kyung-Hi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.3
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    • pp.494-507
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    • 2011
  • In this paper, we propose two schemes to reduce the complexity of fixed-complexity sphere decoder (FSD) algorithm in the ordering and tree-search stages, respectively, while achieving quasi-ML performance. In the ordering stage, we propose a QR-decomposition-based FSD signal ordering based on the zero-forcing criterion (FSD-ZF-SQRD) that requires only a few number of additional complex flops compared to the unsorted QRD. Also, the proposed ordering algorithm is extended using the minimum mean square error (MMSE) criterion to achieve better performance. In the tree-search stage, we introduce a threshold-based complexity reduction approach for the FSD depending on the reliability of the signal with the largest noise amplification. Numerical results show that in 8 ${\times}$ 8 MIMO system, the proposed FSD-ZF-SQRD and FSD-MMSE-SQRD only require 19.5% and 26.3% of the computational efforts required by Hassibi's scheme, respectively. Moreover, a third threshold vector is outlined which can be used for high order modulation schemes. In 4 ${\times}$ 4 MIMO system using 16-QAM and 64-QAM, simulation results show that when the proposed threshold-based approach is employed, FSD requires only 62.86% and 53.67% of its full complexity, respectively.

Stress path adapting Strut-and-Tie models in cracked and uncracked R.C. elements

  • Biondini, Fabio;Bontempi, Franco;Malerba, Pier Giorgio
    • Structural Engineering and Mechanics
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    • v.12 no.6
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    • pp.685-698
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    • 2001
  • In this paper, a general method for the automatic search for Strut-and-Tie (S&T) models representative of possible resistant mechanisms in reinforced concrete elements is proposed. The representativeness criterion here adopted is inspired to the principle of minimum strain energy and requires the consistency of the model with a reference stress field. In particular, a highly indeterminate pin-jointed framework of a given layout is generated within the assigned geometry of the concrete element and an optimum truss is found by the minimisation of a suitable objective function. Such a function allows us to search the optimum truss according to a reference stress field deduced through a F.E.A. and assumed as representative of the given continuum. The theoretical principles and the mathematical formulation of the method are firstly explained; the search for a S&T model suitable for the design of a deep beam shows the method capability in handling the reference stress path. Finally, since the analysis may consider the structure as linear-elastic or cracked and non-linear in both the component materials, it is shown how the proposed procedure allows us to verify the possibilities of activation of the design model, oriented to the serviceability condition and deduced in the linear elastic field, by following the evolution of the resistant mechanisms in the cracked non-linear field up to the structural failure.

Efficiency Improvement of the Fixed-complexity Sphere Decoder

  • Mohaisen, Manar;Chang, Kyung-Hi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.2
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    • pp.330-343
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    • 2011
  • In this paper, we propose two schemes to reduce the complexity of fixed-complexity sphere decoder (FSD) algorithm in the ordering and tree-search stages, respectively, while achieving quasi-ML performance. In the ordering stage, we propose a QR-decomposition-based FSD signal ordering based on the zero-forcing criterion (FSD-ZF-SQRD) that requires only a few number of additional complex flops compared to the unsorted QRD. Also, the proposed ordering algorithm is extended using the minimum mean square error (MMSE) criterion to achieve better performance. In the tree-search stage, we introduce a threshold-based complexity reduction approach for the FSD depending on the reliability of the signal with the largest noise amplification. Numerical results show that in $8{\times}8$ MIMO system, the proposed FSD-ZF-SQRD and FSD-MMSE-SQRD only require 19.5% and 26.3% of the computational efforts required by Hassibi’s scheme, respectively. Moreover, a third threshold vector is outlined which can be used for high order modulation schemes. In $4{\times}4$ MIMO system using 16-QAM and 64-QAM, simulation results show that when the proposed threshold-based approach is employed, FSD requires only 62.86% and 53.67% of its full complexity, respectively.

The Effect of Career Barrier, Satisfaction and Career Decision Making Pattern on Career Search Behavior in Male Nursing Students (남자 간호대학생의 진로장벽, 전공만족도 및 진로의사결정유형이 진로탐색행동에 미치는 영향)

  • Choi, Eun Young;Choi, Mi Jung;Park, Sang Bin
    • The Journal of Korean Academic Society of Nursing Education
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    • v.22 no.3
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    • pp.334-344
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    • 2016
  • Purpose: The study was conducted to investigate the effect of career barrier, satisfaction, and career decision making pattern on career search behaviors in male nursing students. Methods: Data were collected through structured questionnaires that included general characteristics, career barrier, satisfaction, career decision making pattern and career search behaviors and were analyzed by descriptive statistics, ANOVA, t-test, Pearson correlation coefficient and multiple regression using SPSS/PC+ program. Results: The results of the research suggest the two aspects of career search behaviors as being self-exploration and environmental exploration. The rational pattern, among the types of satisfaction and career decision making pattern, was found to have a meaningful effect on self-expression. On the other hand, dependent pattern, among the satisfaction and career decision making pattern, was found to have an effect on career search patterns. Conclusion: It is considered that, based on the results of this study, diversified approaches that consider individual career decision making patterns such as rational pattern and dependent pattern as well as the methods to enhance the satisfaction of male nursing college students for career guidance are needed.