• Title/Summary/Keyword: Structure of Elements

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The Factor Structure of Customer Satisfaction in Libraries (도서관의 이용자 만족도 요인 구조 분석)

  • Lee, Jeong-Ho
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.23 no.1
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    • pp.215-234
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    • 2012
  • The purpose of this study is to investigate asymmetric and nonlinear nature of the relationship between service attributes and global customer satisfaction, and to identify improvement strategies of service quality in libraries. In this study, two methods(such as kano's analysis and importance grid) were used to analyze the factor structure of customer satisfaction in libraries. The results show that two quality elements are classified as excitement factors, twelve quality elements are sorted as hybrid factor and eight quality elements are classified as dissatisfiers.

A Novel Test Structure for Process Control Monitor for Un-Cooled Bolometer Area Array Detector Technology

  • Saxena, R.S.;Bhan, R.K.;Jalwania, C.R.;Lomash, S.K.
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.6 no.4
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    • pp.299-312
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    • 2006
  • This paper presents the results of a novel test structure for process control monitor for uncooled IR detector technology of microbolometer arrays. The proposed test structure is based on resistive network configuration. The theoretical model for resistance of this network has been developed using 'Compensation' and 'Superposition' network theorems. The theoretical results of proposed resistive network have been verified by wired hardware testing as well as using an actual 16x16 networked bolometer array. The proposed structure uses simple two-level metal process and is easy to integrate with standard CMOS process line. The proposed structure can imitate the performance of actual fabricated version of area array closely and it uses only 32 pins instead of 512 using conventional method for a $16{\times}16$ array. Further, it has been demonstrated that the defective or faulty elements can be identified vividly using extraction matrix, whose values are quite similar(within the error of 0.1%), which verifies the algorithm in small variation case(${\sim}1%$ variation). For example, an element, intentionally damaged electrically, has been shown to have the difference magnitude much higher than rest of the elements(1.45 a.u. as compared to ${\sim}$ 0.25 a.u. of others), confirming that it is defective. Further, for the devices having non-uniformity ${\leq}$ 10%, both the actual non-uniformity and faults are predicted well. Finally, using our analysis, we have been able to grade(pass or fail) 60 actual devices based on quantitative estimation of non-uniformity ranging from < 5% to > 20%. Additionally, we have been able to identify the number of bad elements ranging from 0 to > 15 in above devices.

Finite Element Analyses of Cylinder Problems Using Pseudo-General Plane Strain Elements(Planar Constraint) (유사 평면변형률 유한요소를 사용한 실린더 문제의 해석)

  • KWON YOUNG-DOO;KWON HYUN-WOOK;SHIN SANG-MOK;LEE CHAN-BOK
    • Journal of Ocean Engineering and Technology
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    • v.17 no.5 s.54
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    • pp.66-75
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    • 2003
  • Long cylinder, subjected to internal pressure, is important in the analysis and design of nuclear fuel rod structures. In many cases, long cylinder problems have been considered as a plane strain condition. However, strictly speaking, long cylinder problems are not plane strain problems, but rather a general plane strain (GPS) condition, which is a combination of a plane strain state and a uniform strain state. The magnitude of the uniform axial strain is required, in order to make the summation of the axial force zero. Although there has been the GPS element, this paper proposes a general technique to solve long cylinder problems, using several pseudo-general plane strain (PGPS) elements. The conventional GPS elements and PGPS elements employed are as follows: axisymmetric GPS element (GA3), axisymmetric PGPS element (PGA8/6), 2-D GPS element (GIO), 3-D PGPS element (PG20/16), and reduced PGPS elements (RPGA6, RPG20/16). In particular, PGPS elements (PGA8/6, PG20/16) can be applied in periodic structure problems. These finite elements are tested, using several kinds of examples, thereby confirming the validity of the proposed finite element models.

Benchmark tests of MITC triangular shell elements

  • Jun, Hyungmin;Mukai, Paul;Kim, San
    • Structural Engineering and Mechanics
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    • v.68 no.1
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    • pp.17-38
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    • 2018
  • In this paper, we compare and assess the performance of the standard 3- and 6-node MITC shell elements (Lee and Bathe 2004) with the recently developed MITC triangular elements (Lee et al. 2014, Jeon et al. 2014, Jun et al. 2018) which were based on the partitions of unity approximation, bubble node, or both. The convergence behavior of the shell elements are measured in well-known benchmark tests; four plane stress tests (mesh distortion test, cantilever beam, Cook's skew beam, and MacNeal beam), two plate tests (Morley's skew plate and circular plate), and six shell tests (curved beam, twisted beam, pinched cylinder, hemispherical shells with or without hole, and Scordelis-Lo roof). To precisely compare and evaluate the solution accuracy of the shell elements, different triangular mesh patterns and distorted element mesh are adopted in the benchmark problems. All shell finite elements considered pass the basic tests; namely, the isotropy, the patch, and the zero energy mode tests.

Deping characteristics of the Bi-Sr-Ca-Cu-O ceramics (Bi-Sr-Ca-Cu-O 세라믹의 도우핑 특성)

  • 박용필;김영천;황석영
    • Electrical & Electronic Materials
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    • v.9 no.1
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    • pp.1-8
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    • 1996
  • We investigated the effects of doping elements on the Bi-Sr-Ca-Cu-O ceramics. The doping elements can be classified into four groups depending on their supeconducting characteristics in the Bi-Sr-Ca-Cu-O structure. The first group of doping elements(Co, Fe, Ni and Zn) substitute into the copper site and can reduce the critical temperatures of the 2223 and 2212 phases. The second group of doping elements(Y and La) substitute into the Ca site and cause the disappearance of the 2223 phase and increase the critical temperatures in the 2212 phase. The third group of doping elements(P and K) have a tendency to decompose the superconducting phase and reduce the optimal sintering temperature. The fourth group of doping elements(B, Si, Sn and Ba) almost unaffected the superconductivity of the 2223 and 2212 phase.

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An Analysis on Structures of Man's Costume in Byzantine Empire

  • Yoon, Jeom-Soon
    • Journal of Fashion Business
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    • v.8 no.6
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    • pp.57-67
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    • 2004
  • The forms of man's costumes in Byzantine Empire were changed according to each composition of costumes. Those forms of costumes had common features of each period when costumes were included. At the same time, however, the fact that differences existed in accordance with a social position including gender, class, occupation, etc. even though in same period were showed. Analytic elements of man's costumes in Byzantine Empire were selected by important factors. This showed the meanings of position and class in that time. The kinds of analytic elements in man's outwear were various but the forms of costumes were not developed because christianity influenced the forms of clothing in the Middle Ages. As the result of synthesis, the main factor of man's costumes was a tunic in Byzantine Empire of the Middle Ages The phases of the times were reflected on the structure of man's costumes in Byzantine Empire. In particular, religious feature was emphasized, and analytic elements of costumes having meanings showed the features of the society at the Middle Ages. For example, a central analytic element of man's costume, an outer garment was a tunic style of H-silhouette that hid the body line. This was influenced by the phases of the times. Namely, the costume stands as a symbol of the times, and also is a cultural sign that reflects phases like politics, economy, religion.

Design guides to resist progressive collapse for steel structures

  • Mirtaheri, M.;Zoghi, M. Abbasi
    • Steel and Composite Structures
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    • v.20 no.2
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    • pp.357-378
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    • 2016
  • The progressive collapse phenomenon in structures has been interested by civil engineers and the building standards organizations. This is particularly true for the tall and special buildings ever since local collapse of the Ronan Point tower in UK in 1968. When initial or secondary defects of main load carrying elements, overloads or unpredicted loads occur in the structure, a local collapse may be arise that could be distributed through entire structure and cause global collapse. One is not able to prevent the reason of failure as well as the prevention of propagation of the collapse. Also, one is not able to predict the start point of collapse. Therefore we should generalize design guides to whole or the part of structure based on the risk analysis and use of load carrying elements removal scenario. There are some new guides and criteria for elements and connections to be designed to resist progressive collapse. In this paper, codes and recommendations by various researchers are presented, classified and compared for steel structures. Two current design methods are described in this paper and some retrofitting methods are summarized. Finally a steel building with special moment resistant frame is analyzed as a case study based on two standards guidelines. This includes consideration of codes recommendations. It is shown that progressive collapse potential of the building depends on the removal scenario selection and type of analysis. Different results are obtained based on two guidelines.

Effect of connection stiffness on the earthquake-induced progressive collapse

  • Ali, Seyedkazemi;Mohammad Motamedi, Hour
    • Earthquakes and Structures
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    • v.23 no.6
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    • pp.503-515
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    • 2022
  • Global or partial damage to a structure due to the failure of gravity or lateral load-bearing elements is called progressive collapse. In the present study, the alternate load path (ALP) method introduced by GSA and UFC 4-023-03 guidelines is used to evaluate the progressive collapse in special steel moment-resisting frame (SMRF) buildings. It was assumed that the progressive collapse is due to the earthquake force and its effects after the removal of the elements still remain on the structures. Therefore, nonlinear dynamic time history analysis employing 7 earthquake records is used to investigate this phenomenon. Internal and external column removal scenarios are investigated and the stiffness of the connections is changed from semi-rigid to rigid. The results of the analysis performed in the OpenSees program show that the loss of the bearing capacity of an exterior column due to a seismic event and the occurrence of progressive collapse can increase the inter-story drift of the structure with semi-rigid connections by more than 50% and make the structure unable to satisfy the life safety performance level. Furthermore, connection stiffness severely affects the redistribution of forces and moments in the adjacent elements of the removed column.

IDEMPOTENT ELEMENTS IN THE LOTKA-VOLTERRA ALGEBRA

  • Yoon, Suk-Im
    • Communications of the Korean Mathematical Society
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    • v.10 no.1
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    • pp.123-131
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    • 1995
  • The notion of our non-associative algebra is obtained from the Lotka-Volterra system of differential equation describing competitiion between animals or vegetals species and also in the kinetic theory of gasses. For the structure of an algebra, the existence of idempotents is of particular interest. But also from the biological aspect the existence of such elements is of interest because the equilibria of a population which can be described by an algebra correspond to idempotents of this algebra. Thus we present some properties of the general natures for a Lotka-Volterra algebra associated to a weight function and idempotents elements.

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On the Structure of System Matrix of the Multimachine Systems with Constant Impedance Loads and Calculating Algorithm (다수발전기계통의 계통행렬의 구조 및 계산알고리듬에 관한 연구)

  • 권세혁;송길영
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.38 no.11
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    • pp.870-876
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    • 1989
  • A systematic procedure for the elements of system matrix is suggested for the multimachine systems with constant impedance loads. Synchronous machines are represented by either a two-axis model or a classical model. The interrelationship of submatrices of system matrix has been investigated. Once elements of one submatrix are determined, they can be used to calculate the elements of the other submatrix. This algorithm is more effective as the number of generators modeled by a two-axis model increases. It is illustrated for 9-Bus multimachine system.

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