• Title/Summary/Keyword: Soundness

Search Result 490, Processing Time 0.026 seconds

A Form-finding of Planar Tensegrity Structures

  • Lee, Sang Jin
    • Architectural research
    • /
    • v.14 no.4
    • /
    • pp.143-152
    • /
    • 2012
  • A form-finding procedure is presented for planar tensegrity structures. Notably, a simple decision criteria is proposed to select the desirable candidate position vector from the unitary matrix produced by the eigenvalue decomposition of force density matrix. The soundness of the candidate position vector guarantees faster convergence and produces a desirable form of tensegrity without any member having zero-length. Several numerical examples are provided to demonstrate the capability of the proposed form-finding process.

IMPERSONATION ATTACK ON THE STRONG IDENTIFICATION BASED ON A HARD-ON-AVERAGE PROBLEM

  • Koo, Bon-Wook;Kwon, Dae-Sung;Lee, Joo-Young;Song, Jung-Hwan
    • Bulletin of the Korean Mathematical Society
    • /
    • v.47 no.1
    • /
    • pp.63-71
    • /
    • 2010
  • In this paper, we analyze a zero-knowledge identification scheme presented in [1], which is based on an average-case hard problem, called distributional matrix representability problem. On the contrary to the soundness property claimed in [1], we show that a simple impersonation attack is feasible.

A Study on the Development of Tunnel Soundness Evaluation System Using Artificial Neural Network (인공신경망을 이용한 터널 건전도 평가시스템 개발)

  • 김현우;김영근;이희근
    • Proceedings of the Korean Society for Rock Mechanics Conference
    • /
    • 1999.03a
    • /
    • pp.1-7
    • /
    • 1999
  • 터널은 일종의 지하구조물로서 지형, 지질, 기후 및 기상 등과 같이 영향을 미칠 수 있는 주변환경이 매우 다양할 뿐만 아니라 예기치 못한 외력이 작용하여 구조물에 중대한 문제를 유발할 수도 있는데, 현재 상황으로는 여러 안전진단보고서에서 볼 수 있는 바와 같이 터널에 발생한 일련의 변상현상을 분석하여 그 원인을 규명하고 적절한 보수보강대책을 마련함으로써 예상치 못한 변상에 대한 터널 안전성을 확보하는 작업에 초점이 맞추어지고 있다. (중략)

  • PDF

Landscape Scale Ecosystem Evaluation for Sustainable Landuse Planning (지속가능한 토지이용을 위한 경관규모 생태계평가기법 연구)

  • Hwang, Kook-Woong;Park, So-Yoon
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.6 no.1
    • /
    • pp.78-84
    • /
    • 2003
  • The purpose of this study is to evaluate the ecosystem soundness in landscape scale using landscape indices, and to extract regional information that can be used for sustainable landuse planning. About BongWha-gun, the landcover classification using Landsat TM images and patch analysis ware carried out, and some landscape indices were calculated using geographic information system(GIS) and patch analyst program. As the results of this study, Seokpo, Jaesan and Sochun got higher scores in landscape indices related to the ecosystem soundness. But, Bonghwa-eup got lowest scores in the 10 regions. When compared with normalized difference vegetation index(NDVI), this result showed consistency to some degree. Although, there needs more supplementary studies, it is anticipated that landscape scale ecosystem evaluation using landscape indices can gives us some informations related to sustainable landuse planning.

  • PDF

The Effect of Corporate Social Responsibility and Audit Size on Credit Rating (기업의 사회적 책임과 감사인 규모가 기업신용등급에 미치는 영향)

  • Jeon, Jin-Ho
    • Journal of the Korea Convergence Society
    • /
    • v.9 no.1
    • /
    • pp.1-8
    • /
    • 2018
  • This study analyzed annual final sample data from 159 companies based on firms selected as economic justice companies by Economic Justice Institute in Citizens' Coalition for Economic Justice in South Korea according to interest variables from 2005 until 2011. Analyzed results are as follows. First, higher scores in soundness and corporate social activities among CSR items suggested that corporate credit rating upgraded. This indicates that credit rating institutions give a good evaluation on their social activities and reflect them in credit rating assessment. However, environmental protection satisfaction and corporate credit rating showed the opposite results. Second, high objectivity and contribution to the economic development as well as supervision by giant auditors had substantial effects on higher corporate credit rating. In contrast, high soundness and supervision by giant auditors reduced corporate credit rating. Based on this outcome, it is estimated that there is a discriminatory response among CSR activities in terms of credit rating evaluation conducted by credit rating institution.

Development of Technology Portfolio Analysis method for Technology-outsourcing of Pharmaceutical cooperations (제약기업의 기술 아웃소싱을 위한 기술포트폴리오 분석 방법 개발)

  • Hong, Sukchul
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.14 no.11
    • /
    • pp.5809-5818
    • /
    • 2013
  • This study proposes a technology portfolio analysis method for technology outsourcing of pharmaceutical cooperations by applying the concepts of 'Pipeline Soundness' and 'Patent Validity'. This study also applied the developed portfolio analysis method to a 'real world case' of Amgen's acquisition of Onyx Pharmaceuticals to prove the applicability of the method to the real world cases and investigated the validity of the acquisition affair between the two companies. The results of portfolio analysis showed that Amgen's technology portfolio will be improved by acquiring Onyx Pharmaceuticals especially in cancer field which is their main field. So we concluded that Amgen's choice of Onyx pharmaceuticals as a source of technology outsourcing was reasonable. We think that the technology portfolio analysis method developed by this study will be a valuable tool for pharmaceutical cooperations for investigating their current technology status and selecting target companies for technology outsourcing.

Evaluation of Usability for Sub-base of Muddy Stone produced on Site (현장발생 이암계 퇴적암의 보조기층 적용성 평가)

  • Kim, Jin-Cheol
    • International Journal of Highway Engineering
    • /
    • v.7 no.3 s.25
    • /
    • pp.93-100
    • /
    • 2005
  • Rock produced in situ has been used as the road construction materials in consideration of economies. However, because sedimentary rock is rapidly weathered, it is hard to decide appropriateness of quality specifications. This study aims at evaluation of usability for sub-base of muddy stone produced in situ. Test results show that the abrasion ratio is fitted for specifications, but weight loss in 37.5$\sim$16mm after Los Angeles abrasion test shows 47% in muddy stone in comparison with 20$\sim$30% in gneiss and sandstone. The soundness of aggregate shows higher value in muddy stone than in gneiss and sandstone. The weight loss from accelerated weathering test due to freezing and drying show 58% in muddy stone in comparison with 308$\sim$21% gneiss and sandstone.

  • PDF

Joining Ability and Mechanical Properties of Friction Stir Lap Welded A5052-H112 Alloy (A5052-H112 합금의 겹치기 마찰교반접합 건전성)

  • Ko, Young-Bong;Choi, Jun-Woong;Park, Kyeung-Chae
    • Journal of Welding and Joining
    • /
    • v.28 no.1
    • /
    • pp.34-40
    • /
    • 2010
  • In Friction Stir Lap Welding(FSLW), the movement of material within the weld was more important than the microstructure, due to the interface present between the sheets. Thus, The soundness of free defect, Effective Sheet Thickness(EST) and width of joint were most important factor of mechanical properties. Specimens by lap joint types that were 'A-type' and 'R-type' were made in this study. A-type tensile specimen was loaded at advancing side and R-type tensile specimen was loaded at retreating side. Macro-, micro-structural observation and mechanical properties of FSLW A5052-H112 alloy ware investigated under varying rotating and welding speed. The results were as follows: Material hook formed decreasing after sharply increasing was appeared at the end interface of joint area in advanced side, and material hook formed decreasing after smoothly increasing was observed at that in retreated side. Tensile load had no relation with defects. As rotating speed was higher, tensile strength was increasing and EST was decreasing regardless of joint types. joint efficiency was over 70%. In a result of fractography, fracture in A-type was partially occurred by dimple in SZ, and fracture in R-type was generally occurred by dimple in HAZ.

Groping the Environmental Education Method based on the Ecological Principles (생태학의 원리에 기초한 환경교육 방법의 모색)

  • 이창석;유영한
    • Hwankyungkyoyuk
    • /
    • v.15 no.2
    • /
    • pp.1-13
    • /
    • 2002
  • The progress of environmental science and technology in the developed countries has been rapid in recent years. Particularly remarkable has been the advancement of various pollutant control measures, which have brought the pollution of inorganic factors such as air and water under control. In contrast, diversity of the ecosphere, of which man is a part, is being steadily impoverished and the biological community is getting unvaryingly uniform. These phenomena were brought about by the expansion of artificial environment such as new industrial complexes, transportation facilities and urban development. Man has constructed uniform and artificial environment, believing in the premise of confrontation with nature, to such a scale that the natural environment and biological community have lost their balance. This will increasingly endanger the soundness of the biotic environment of nature, which constitutes the potential foundation both for the survival environment of man as biological entity and for the development of human civilization. In order to guarantee the soundness of man's body, intelligence and sensitivity as wholesome gene pool on the earth and for the future of man, primarily important environmental education is the understanding of how man can everlasting exist in and with the survival environment. In view of this reality, it is vitally important to create ecologically diverse and well-balanced environment with living materials, i.e., vegetation in order to secure lasting survival environment for man. This task is urgently required in highly artificial environment where non-biological materials have forced the impoverishment of the biological community. Therefore, environmental education for the future should not be totally oriented to technology as that in the past nor it is limited to the medical aspect where well-being of human is the sole object of concern. That is to say, environmental education for the future should be one that provides knowledge that human can understand his place based on the ecological concept and thereby make him to have ethical consciousness that he can control his behavior within the reasonable level for ecological niche who he is located.

  • PDF

River Embankment Integrity Evaluation using Numerical Analysis (수치해석을 이용한 하천제방의 건전도 평가)

  • Byun, Yo-Seph;Jung, Hyuk-Sang;Kim, Jin-Man;Choi, Bong-Hyuck;Kim, Kyung-Min;Chun, Byung-Sik
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2009.09a
    • /
    • pp.524-528
    • /
    • 2009
  • An influence factors for soundness evaluation of river levee include resistibility and embankment for piping of ground consisting embankment in case piping, permeability coefficient of ground, height of embankment, the width of crest, material characteristics of embankment and foundation ground, shape of embankment slope, an influence for penetration of rainfall or river water in case slope stability. In this study, it was operated a feasibility investigation of existing design result, stability evaluation for permeability coefficient use and permeability coefficient change of foundation ground to investigate an influence in line with permeability coefficient change for result of river levee penetration analysis. The evaluation results of influence factors, the permeability coefficient used in design and it was evaluated influence in safety factor of piping. After the evaluation of influence factors, the permeability coefficient used in the design appears with the fact that differs in a design report about same soil, Accordingly, the stability investigation of embankment by application of literature data can affect stability evaluation results by change factors like a permeability coefficient, void ratio. It should be certainly used material properties by a test in soundness evaluation of river levee.

  • PDF