• Title/Summary/Keyword: structure of stand

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Optimal Design of a New Rolling Mill Based upon Stewart Platform Manipulator : Maximization of Kinematic Manipulability (병렬구조 신 압연기의 최적설계 : 조작성 및 제어성능의 최대화)

  • Hong, Geum-Sik;Lee, Seung-Hwan;Choe, Jin-Tae
    • Journal of Institute of Control, Robotics and Systems
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    • v.8 no.9
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    • pp.764-775
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    • 2002
  • A kinematic and dynamic optimal design of a new parallel-type rolling mill based upon Stewart platform manipulator is investigated. To provide sufficient degrees-of-freedom in the rolling process and the structural stability of each stand, a parallel manipulator with six legs is considered. The objective of this new parallel-type rolling mill is to permit an integrated control of the strip thickness, strip shape, pair crossing angle, uniform wear of the rolls, and tension of the strip. By splitting the weighted Jacobian matrices Into two parts, the linear velocity, angular velocity, force, and moment transmissivities are analyzed. A manipulability measure, the ratio of the manipulability ellipsoid volume and the condition number of a split Jacobian matrix, is defined. Two kinematic parameters, the radius of the base and the angle between two neighboring Joints, are optimally designed by maximizing the global manipulability measure in the entire workspace. The maximum force needed in the hydraulic actuator is also calculated using the structure determined through the kinematic analysis and the Plucker coordinates. Simulation results are provided.

A Study of Cyber University Core Competence: The Consumer's Perception about Off-line Base University (사이버대학교의 핵심역량에 관한 연구 : 오프라인 기반 대학에 대한 소비자 지각을 중심으로)

  • Lim, Yang Whan;Kwon, Soon Hong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.4 no.4
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    • pp.127-138
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    • 2008
  • To study about core capability which becomes the kernel of sustainable competitive advantage (SCA) in cyber university which confronts competition-deepening circumstance, the value and importance of brand and educational services of cyber universities which stand on the basis of offline university were examined. Moreover, core capability based on the importance of cyber university service was searched, and its strategic course were suggested. Within research processes, competition environment of cyber university was forecasted, and importance to build up its core capability was examined. Moreover, conjoint analysis was carried out for three offline cyber universities. As a result of survey analysis, effectiveness of cyber university brand showed greater influence than other characteristics in terms of the influence which affects consumer preference for cyber university. Therefore, to overcome weaknesses of brand asset in low brand power cyber university, establishment of strong core capability which reflects consumer preference is needed to carry out differentiation strategy or concentration strategy, and it is necessary to consider the introduction of new competitiveness structure.

수출공산품(輸出工産品)의 국제경쟁력강화(國際競爭力强化)를 위(爲)한 품질관리실태조사(品質管理實態調査)와 그 촉진방안(促進方案)에 관(開)한 연구(硏究)

  • Sin, Yong-Baek;Kim, Won-Jung;Kim, Yeong-Guk
    • Journal of Korean Society for Quality Management
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    • v.7 no.1
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    • pp.15-25
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    • 1979
  • Recently ('70~'76) the average annual export expansion rate was 31.7% (the foremost rate in the world). In '77 the export amounted to 10 billion dollars, and 12.7 billion dollars in '78. The tendeney has been to increase yearly. In view of the structure of export goods, the major export products have been changed from primary industrial materials (86% of the total export in '76) to industrial products (82% in '75). These trends are due to the remarkable progress in the technology advancement. Only 33.6% of the total export items can compete with those of advanced industrial countries in both of price and non-price competitiveness, therefore ours stand in weak position to that of advanced industrial countries. In order to promote good will and strengthen international competitiveness, the major stress of this paper is first of all on the problems of Quality Control, which covers the present states and derived problems of Quality control. These are investigated and analyzed to insure the rational application of Quality Control to the major export goods with a view of the establishment of the direction and systematic improving means of Quality Control.

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A basic study on Visual judgment method for the Dent of Lightweight wall surface (경량벽체 표면의 패임에 대한 시각적 판단방법에 관한 기초적 연구)

  • Kim, Jin-Sik;Shin, Yun-Ho;Choi, Soo-Kyung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2015.11a
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    • pp.36-37
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    • 2015
  • Recently, there has been a rapid increase in demand for lightweight walls for their use as interior partitions, as types of structure have gradually changed from shear wall structures to column structures or flat plate column wall systems. The lack of resisting force in lightweight walls is found by measuring the depth of dents in impact resistance tests, but it is not a direct factor of impact resistance. However, in the user's position, dents of over a certain size are clearly a factor that visually reminds the need for repair. In this study, we reviewed relative methods of assessment of the need for repair based on the visual means of determination (sensory test) on the dents on lightweight walls. Dents were found to stand out starting from depths of about 4mm, and the depth of roughly 5mm was found to be the criterion for determining the necessity of repair for men, while it was 4mm for women.

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A Study on the Remodeling of Living Research about living environment renovation for disabled - Based on 27 cases of residence renovation in Incheon city - (신체장애인의 주거환경 개조에 관한 연구 - 인천시 주거개조 사례 27개를 중심으로 -)

  • Cho, Cheol-Ho;Soh, Jun-Young
    • Korean Institute of Interior Design Journal
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    • v.19 no.2
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    • pp.234-242
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    • 2010
  • The twenty seven houses at Incheon city, were remodeled in 2009 for the physically handicapped people. This research had been done the analysis of the itemized questionnaire by the needs of the physically handicapped for their better living environment and suggested the following remodeling devices. First of all, there was the priority for the remodeling of their living facilities. According to their priority, they wanted to remodel their bathroom, kitchen & dining room, veranda, living room, and hall way. These were based on their needs of movement, personal hygiene, convenient closet, and cabinet usage. In particular, their demands were shown as followings. The wheelchair using handicapped people required safe doorknobs, unslippery floor materials, removal of step levels, and heights adjustable washing stand for their bathroom. They also requested washboard, non-threshold, and automatic door locks. Otherwise, the disabled in critical condition who could not move anything preferred the remodeling of inner structure of living spaces and automatic door system. The slight disabled and the families those who have the disabled demanded the remodeling of kitchen & dining room, and preferred the reorganization of closet, cabinets, floor tiles, and turncock. The remodeling of bedroom was mostly requested by the disabled women, people with the brain disorder, and disabled people in critical condition who could not move anything. They wanted the remote controlled lightings.

Development of Molecular Biological Methods to Analyze Bacterial Species Diversity in Freshwater and Soil Ecosystems

  • Lee, Dong-Hun;Noh, Sung-Ae;Kim, Chi-Kyung
    • Journal of Microbiology
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    • v.38 no.1
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    • pp.11-17
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    • 2000
  • A new method was developed for the rapid analysis of diverse bacterial species in the natural environment. Our method is based on PCR-single-strands-conformation polymorphism (PCR-SSCP) and selective isolation technique of single-stranded DNA. Variable V3 fragments of 16S rDNA were amplified by PCR with bacterial 16S rDNA primers, where one of the primers was biotinylated at the 5'-end. The biotinylated strands of the PCR products were selectively isolated by using streptavidin paramagnetic particles and a magnetic stand, to prevent SSCP analysis producing heteroduplexes from heterogeneous DNA samples. The selected strands were separated by electrophoresis on a polyacrylamide gel, and detected by silver staining. Analysis of PCR products from 8 bacterial strains demonstrated their characteristic DNA band patterns. In addition, changes in the structure of the bacterial community and species diversity in the microcosm treated with phenol could be monitored. After 3 weeks of incubation, phenol and its intermediate, 2-hydroxy-muconic-semialdehyde, were degraded by indigenous bacteria. These dominating bacterial populations were identified as strong bands on an SSCP gel. Therefore, this study provides useful tools for microbial community analysis of natural habitats.

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Development of Direct Seeded Rice Cultivation in the Future (벼 직파재배(直播栽培)의 기술적(技術的) 발전(發展) 방향(方向))

  • Park, Seok-Hong;Lee, Chul-Won
    • Korean Journal of Weed Science
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    • v.12 no.3
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    • pp.292-308
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    • 1992
  • Recently agricultural situations are being placed in unfavourable socio-economic environment as followed by rapid decrease of rural population, poor labor quality and high wages of rural society due to high speedy industrialization of social structure in Korea. In addition to those circumstances, under the UR system to be expected in the early future, free trade of agricultural products will be faced inevitably in Korea. Practically prices of rice as a principle food in this country are expensive about three times compared to those of foreign rice markets, and so how to increase the international competitiveness and food supplies are important problems to be solved rapidly. Accordingly an urgent goal is reduction of agricultural production cost by the improvement of labour productivity as a labour saving and cost down cultivation methods as the direct seeding cultivation in rice. But there are many problems in the direct seeded rice cultivation. The important things to be improved in that cultivation are development of rice varieties with lodging tolerance, effective seedling stand, weed control, irrigation management and fertilizing and so on. Moreover agricultural basis as irrigation facilities, land consolidation and farm machineries must be improved for the stability of rice cultivation in the future.

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A graphical user interface for stand-alone and mixed-type modelling of reinforced concrete structures

  • Sadeghian, Vahid;Vecchio, Frank
    • Computers and Concrete
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    • v.16 no.2
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    • pp.287-309
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    • 2015
  • FormWorks-Plus is a generalized public domain user-friendly preprocessor developed to facilitate the process of creating finite element models for structural analysis programs. The lack of a graphical user interface in most academic analysis programs forces users to input the structural model information into the standard text files, which is a time-consuming and error-prone process. FormWorks-Plus enables engineers to conveniently set up the finite element model in a graphical environment, eliminating the problems associated with conventional input text files and improving the user's perception of the application. In this paper, a brief overview of the FormWorks-Plus structure is presented, followed by a detailed explanation of the main features of the program. In addition, demonstration is made of the application of FormWorks-Plus in combination with VecTor programs, advanced nonlinear analysis tools for reinforced concrete structures. Finally, aspects relating to the modelling and analysis of three case studies are discussed: a reinforced concrete beam-column joint, a steel-concrete composite shear wall, and a SFRC shear panel. The unique mixed-type frame-membrane modelling procedure implemented in FormWorks-Plus can address the limitations associated with most frame type analyses.

Minimal Areas and Community Structures of Pinus densiflora Forests and Quercus mongolica Forests (소나무림 및 신갈나무림의 최소면적과 군락구조)

  • Kim, Jong-Woon;Deuk-Im Lee;Woen Kim
    • The Korean Journal of Ecology
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    • v.18 no.4
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    • pp.451-462
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    • 1995
  • A comparative study on the minimal areas and the community structures in pine IPinus densiflora) and oak (Quercus mongolica) frests was carried out. Basic tools used in the present study were species diversity and classical ayntaxonomy (Z.-M. School) of the phytocoenosis. Total 120 nest-quadrats in 40 stands situated at the syngeographical region of the Lindero-Quercion mongolicae were investigated. Each stand was classified on the basis of species combination, and species abundance was computed with net contribution degree (NCD). Composition ratio of plant-from and rate of actual species diversity (ASD) to syntaxa were computed for better interpretation of the minimal areas. Four syntaxa were structured: Saso-Quercetum mongolicae, Viola albida-Quercus mongolica community, Carex hummilis-Pinus densiflora community and Juniperus rigida-Pinus densiflora community. Their minimal areas were determined as 305, 196, 169, and 81 ㎡, respectively. Aconsistent regularity between species composition ratio and community structure in the multi-layered plant community was hardly found. The minimal areas increased linearly with increasing rate of ASD, and a phytocoenosis developed by diverse arboreta in the understory and shrub-layer should be investigated with larger sampling sizes.

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The Factor and Analysis on the Face Image to Hairstyle Variation - using by Computer Graphic Simulation- (Hairstyle 변화에 의한 얼굴 이미지 요인과 분석 -Computer Graphic simulation을 이용하여 -)

  • Do Ju Yeun;Kown Young Suk
    • Journal of the Korean Society of Clothing and Textiles
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    • v.16 no.3 s.43
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    • pp.243-250
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    • 1992
  • The purposes of this research were to analyze factor structure and the face image to hairstyles which was made by Computer graphic simulation. To select ten hairstyle, a standard face selected between women of $20\~25$ years, and four factor (straight, curl, hair length, front hair, part hair) which were made of stand of hairstyle were applied. The results were as follows; 1 face image factor by hairstyle variation were found to five factor; negative and pogitive, indivisuality, youthfulness, unbanity, intelligence. 2. The result of analysis to face image by hairstyle factor were (1) In the hair state, straight hair was explained by the youthful, pure, decent image than curl. (2) In the hair length, the longer hair was explained by the more feminine, softness image. The shorter hair was explained by the more vigorous, youthful image. (3) In the presence of front hair, bang hair was explained by the commonness, moderate, classical image than all back hair (4) In the part hair, part hair was explained by the modern and unbanity image than no part hair.

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