• 제목/요약/키워드: high-dimensions

검색결과 1,424건 처리시간 0.043초

비정질 $As_{10}Ge_{15}Te_{75}$박막의 D.C. 스위칭 임계전압 특성 (The characteristics of D.C. switching threshold voltage for amorphous $As_{10}Ge_{15}Te_{75}$ thin film)

  • 이병석;이현용;이영종;정홍배
    • E2M - 전기 전자와 첨단 소재
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    • 제9권8호
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    • pp.813-818
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    • 1996
  • Amorphous As$_{10}$Ge$_{15}$ Te$_{75}$ device shows the memory switching characteristics under d.c. bias. In bulk material, a-As$_{10}$Ge$_{15}$ Te$_{75}$ switching threshold voltage (V$_{th}$) is very high (above 100 volts), but in the case of thin film, V$_{th}$ decreases to a few or ten a few volts. The characteristics of V$_{th}$ depends on the physical dimensions such as the thickness of thin film and the separation between d.c. electrodes, and the annealing conditions. The switching threshold voltage decreases exponentially with increasing annealing temperature and annealing time, but increases linearly with the thickness of thin film and exponentially with increasing the separation between d.c. electrodes. The desirable low switching threshold voltage, therefore, can be obtained by the stabilization through annealing and changing physical dimensions.imensions.sions.

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실내색채의 공간효과에 관한 실험연구 - 거실의 천장 , 벽 , 바닥 색채를 중심으로 - (An Experimental Study on the Spatial Effects of Colours - with relevance to colours of ceilings , walls and floors in living rooms -)

  • 조원덕
    • 한국주거학회논문집
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    • 제3권2호
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    • pp.13-19
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    • 1992
  • The purpose of this study is to grasp spatial effects of colours in interior design. The visual feeling in the 1/10 living room scale models that are different in the colour combination of ceilings, walls and floors is judged using a semantic scale of the fifteen adjectives. The major findings are as follows; 1) As a result of factor analysis, three dimensions, "evaluation", "activity" and "warmness" are extracted. Dimension 1, "evaluation", is most greatly affected by the chroma and hue of the room colour, dimension 2, "activity", by the hue and value, by the difference in hue and value of ceilings, walls and floors, dimensions 3, "warmness", by mainly the hue of the rooms. 2) Concerning the spatial effects of colour, the subjects felt higher vlaue with relevance to the hue of GY, Y, low chroma and high value. The room colours other than walls is felt more comfortable in similar colour, especially hue and value.re comfortable in similar colour, especially hue and value.

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대규모 시스템 통합 프로젝트 환경에 있어서 IT인력의 이직 원인에 관한 추적연구 (Trace Research on IT Personnel Turnover in Large Scale Sl Projects)

  • 조남재;장성주
    • 정보기술과데이타베이스저널
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    • 제8권2호
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    • pp.61-69
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    • 2001
  • System Integration Projects, especially in public sector, have a tendency of growing in size and duration. Under such environment the effects of IT personnel turnover becomes a serious problem. In addition a high rate of turnover hinders shill accumulation and competitiveness obtainment. In this research we explored the reasons of turnover by way of tracing IT personnel who have involved in large-scale SI projects and moved or quit before the completion of the projects. Based on previous research we identified three dimensions of variables that affected turnover : task-related dimension, human relations dimension, treatment-related dimension. We used these dimensions as a guideline for the interview and questioning exploration. Implications from the research for improving IT Personnel management are also elaborated.

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대학 기숙사의 서비스품질 측정 및 중요도-성과분석 (A Measure for Service Quality of University Dormitory and Importance - Performance Analysis)

  • 류문찬
    • 품질경영학회지
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    • 제37권1호
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    • pp.56-68
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    • 2009
  • A measure for service quality of university dormitory is developed to gain a better understanding of the quality issues that impact on students' experiences and to improve service quality. Literature survey, thorough discussion with staff members and a pilot test are utilized to elicit attributes of service quality. Factor analysis is used to group the service quality attributes into dimensions. The resulting measure is consisted of 6 dimensions; competence, attitude, facility, amenity, security and discipline. Importance-performance analysis is utilized to verify which factors to be focused on with high Priority to improve dormitory service.

Variation Stack-Up Analysis Using Monte Carlo Simulation for Manufacturing Process Control and Specification

  • Lee, Byoungki
    • 품질경영학회지
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    • 제22권4호
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    • pp.79-101
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    • 1994
  • In modern manufacturing, a product consists of many components created by different processes. Variations in the individual component dimensions and in the processes may result in unacceptable final assemblies. Thus, engineers have increased pressure to properly set tolerance specifications for individual components and to control manufacturing processes. When a proper variation stack-up analysis is not performed for all of the components in a functional system, all component parts can be within specifications, but the final assembly may not be functional. Thus, in order to improve the performance of the final assembly, a proper variation stack-up analysis is essential for specifying dimensional tolerances and process control. This research provides a detailed case example of the use of variation stack-up analysis using a Monte Carlo simulation method to improve the defect rate of a complex process, which is the commutator brush track undercut process of an armature assembly of a small motor. Variations in individual component dimensions and process mean shifts cause high defect rate, Since some dimensional characteristics have non-normal distributions and the stack-up function is non-linear, the Monte Carlo simulation method is used.

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헬리컬기어 블랭크 열간단조의 유한요소해석 (Finite-Element Analysis of a Helical-Gear Blank Hot-Forging)

  • 안승우;박종진
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1995년도 제2회 단조심포지엄 단조기술의 진보
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    • pp.180-187
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    • 1995
  • Helical gears are machined from blanks, which are usually prepared by forging cylindrical billets at high temperatures through buster, blocker and finisher processes. As dimensions of the blank are closer to those of the machined part, machining cost can be more reduced. Therefore, there are a lot of efforts being made to optimize the forging processes in order to produce near-net shaped blanks. In the present investigation, a rigid viscoplastic finite element technique was used to analyze a helical gear blank hot forging processes and deformation, strain and temperature distributions, forging load variations during forging were obtained. In the paper, it is discussed how these results can be utilized to optimize die design, billet dimensions and press usage.

선형계획법의 해의 이동에 관한 시각화 (On visualization of solutions of the linear Programming)

  • 이상욱;임성묵;박순달
    • 경영과학
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    • 제19권1호
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    • pp.67-75
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    • 2002
  • This paper deals with the visualization method of solutions of the linear programming Problem. We used the revised simplex method for the LP algorithm. To represent the solutions at each iteration, we need the informations of feasible legion and animated effect of solutions. For the visualization in high dimension space, we used the method of Projection to the three dimensions if the decision variable vector is over three dimensions, and we studied the technique of preserving original Polyhedral information such as the number of vertices. In addtion, we studied the method of visualizing unbounded feasible region and the adjacency relationship of the vortices welch is Indispensable to cisualize feasible legion.

An Analysis of Fraction Operation Sense to Enhance Early Algebraic Thinking

  • Lee, Jiyoung;Pang, Jeongsuk
    • 한국수학교육학회지시리즈D:수학교육연구
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    • 제16권4호
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    • pp.217-232
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    • 2012
  • While many studies on early algebra have been conducted, there have been only a few studies on the operation sense as the fundamental element of algebraic thinking, especially the fraction operation sense. This study explored the dimensions of fraction operation sense and then investigated students' fraction operation sense. A total of 183 of sixth graders were surveyed and 5 students who showed high operation sense were clinically interviewed in order to analyze their algebraic thinking in detail. The results showed that students had a tendency to use direct calculation or employ inappropriate operation sense rather than to use the structure of operation or the relation between operations on the basis of algebraic thinking. This study implies that explicit instruction on early algebra is necessary from the elementary school years.

방전공간 치수 변화에 따른 FFL(Flat Fluorescent Lamp)의 방전특성 (Discharge characteristics of FFL as the change of discharge space dimensions)

  • 윤성현;박철현;조민정;임민수;권순석;임기조
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 C
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    • pp.497-499
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    • 2000
  • The characteristics of Xe discharge lamp are described in this paper. In this paper, FFL is changed discharge space dimensions like discharge space gap, phosphor layer and dielectric layer thickness to find FFL with high efficiency.

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Dimensionality reduction for pattern recognition based on difference of distribution among classes

  • Nishimura, Masaomi;Hiraoka, Kazuyuki;Mishima, Taketoshi
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -3
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    • pp.1670-1673
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    • 2002
  • For pattern recognition on high-dimensional data, such as images, the dimensionality reduction as a preprocessing is effective. By dimensionality reduction, we can (1) reduce storage capacity or amount of calculation, and (2) avoid "the curse of dimensionality" and improve classification performance. Popular tools for dimensionality reduction are Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA), and Independent Component Analysis (ICA) recently. Among them, only LDA takes the class labels into consideration. Nevertheless, it, has been reported that, the classification performance with ICA is better than that with LDA because LDA has restriction on the number of dimensions after reduction. To overcome this dilemma, we propose a new dimensionality reduction technique based on an information theoretic measure for difference of distribution. It takes the class labels into consideration and still it does not, have restriction on number of dimensions after reduction. Improvement of classification performance has been confirmed experimentally.

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