• Title/Summary/Keyword: transition elements

Search Result 388, Processing Time 0.028 seconds

Calculation TRL using Integration Readiness Between Technologies for Supporting Technology-transition of Defense Technologies to the Defense Weapons System (국방시스템 기술전이지원을 위한 기술성숙도 도출에 관한 연구)

  • Bae, Yoon-Ho;Choi, Seok-Cheol
    • Korean Management Science Review
    • /
    • v.26 no.3
    • /
    • pp.157-167
    • /
    • 2009
  • Technology transition from defense technology to weapon system is an important process for defense acquisition program. Many countries such as USA, UK, Australia and Republic of Korea use technology readiness level (TRL) as a tool for technology transition by identifying critical technology elements (CTEs) and assessing the technology maturity. In this paper we review a transition process for the defense acquisition. Then we suggest a method to evaluate system's TRL using each component TRL and integration readiness level (IRL) between each technologies. We apply the method to an ACTD project. A result show that technology maturity is influenced by integration between technologies.

3D Variable Node Solid Elements with Drilling Degrees of Freedom (회전자유도를 가지는 3차원 변절점 고체요소의 개발)

  • 최창근;정근영
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 1995.04a
    • /
    • pp.9-16
    • /
    • 1995
  • A new three-dimensional transition solid element with drilling degrees of freedom is presented. The proposed transition element is established by adding variable nodes to a basic 8-node element for an effective connection between the refined region and the coarse. The derivation of the element in this paper is based on the variational principles in which the drilling rotations are introduced as independent variables. This element was also improved through the addition of modified non-conforming modes. Numerical examples show that performance of the element and the applicability to 3D adaptations are satisfactory.

  • PDF

A new quadrilateral 5-node non-conforming membrane element with drilling DOF

  • Lee, Tae-Yeol;Choi, Chang-Koon
    • Structural Engineering and Mechanics
    • /
    • v.14 no.6
    • /
    • pp.699-712
    • /
    • 2002
  • In this paper, a new quadrilateral 5-node non-conforming membrane element with drilling degrees of freedom is presented. The main advantage of these elements is the relatively small number of integration points to evaluate a stiffness matrix comparing to the existing transition membrane elements (CLM elements). Moreover, the presented elements pass the patch test by virtue of the Direct Modification Method incorporated into the element formulation. The presented 5-node elements are proved to be very efficient when used in the local mesh refinement for the in-plane structures which have stress concentrations. And some numerical studies also show the good performance of the new element developed in this study.

Trace elements analysis in some medicinal plants using graphite furnace-atomic absorption spectroscopy

  • Anal, Jasha Momo H.;Chase, Petevino
    • Environmental Engineering Research
    • /
    • v.21 no.3
    • /
    • pp.247-255
    • /
    • 2016
  • Ten trace elements (Mg, Ca, V, Cr, Mn, Fe, Cu, Zn, Mo, and Cd) were determined in seven traditionally used wild medicinal plants of the Nagas in the North-East India viz Cynoglossum furcatum Wallich, Elsholtzia blanda Bentham, Lycopodium cernuum Linnaeus, Potentilla fulgens Wallich ex Hooker, Swertia macrosperma C.B. Clarke, Thalictrum foliolosum DC and Valeriana jatamansi Jones. Plant samples were dried, weighed, digested and analyzed for their mineral distribution level ranging from trace to major elements by graphite furnace-atomic absorption spectroscopy. All the medicinal herbs studied were found to contain the ten elements analyzed. The elemental concentration is given in mg/kg. Mg and Ca are present in high concentrations in both the roots and leaves of the plant samples. Among trace transition metals Fe had the highest concentration, followed by Mn, Cr, Cu, V, Zn, and Mo. Analysis showed that the toxic Cd element was at a lower concentration and is within the permissible limit of FAO/WHO, California standards and United States Pharmacopeia Limit for Nutritional Supplements.

A Study on Efficient Analysis of Delamination Buckling of Composite Structures (효율적인 복합재료구조물의 delamination buckling 해석기법에 관한 연구)

  • 황재웅;김용협
    • Proceedings of the Korean Society For Composite Materials Conference
    • /
    • 2000.04a
    • /
    • pp.80-84
    • /
    • 2000
  • A mesh superposition technique is presented for an efficient analysis of structural behavior. Refined child mesh is superimposed over parent elements for the region of interest. It is a kind of adaptive mesh refinement, which allows locally refined mesh without introducing transition region or multipoint constraints. Proper boundary condition is necessary to avoid redundant rigid body motion and kinematic compatibility between neighbor elements. Delamination buckling analysis is conducted to demonstrate accuracy and efficiency of the present method.

  • PDF

Equivalent Nodal Forces of The Solid Element with Rotational Degrees of Freedom (회전자유도가 있는 입체요소의 등가절점하중)

  • 최창근;정근영
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 1995.10a
    • /
    • pp.161-168
    • /
    • 1995
  • The variable-node solid element with rotational degrees of freedom has been developed far efficient connection of transition zones and far connection of different types of elements with rotational degrees of freedom. In applying this new element to engineering problems, it is necessary to fine the relations between tractions and equivalent nodal farces. In this case, the equivalent forces in solid element with rotational degrees of freedom and ratational forces are a bit different from that af conventional solid elements. Some typical examples are presented.

  • PDF

A Study on the Socio-Technical Transition in Electric Lighting : from Incandescent Lamp to Fluorescent Lamp (전기조명의 사회기술전환 연구 : 백열램프에서 형광램프로)

  • Kim, Jaeil;Lee, Heesang
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.29 no.3
    • /
    • pp.8-21
    • /
    • 2015
  • Technology for electric lighting has been evolving from Incandescent Lamp(IL) through Fluorescent Lamp(FL) and currently to Solid State Lighting(SSL) such as LED for more than 130 years of time. However, it took more than 100 years until the transition from IL to FL across overall society. That is because the transition is the Socio-Technical Transition(STT) which involves various social elements. This study investigated and analyzed the theories regarding STT, and applied the Multi-Level Perspective(MLP) theory to the case of electric lighting. A qualitative contents analysis was used with secondary data as research method, and the analyzed result was visualized based on the frame of MLP theory. The STT of electric lighting from IL to FL took place as the order of Technical Niche, Socio-Technical Regime and Landscape. Specifically, in Technical Niche level: Establishing Market Niche, Price-Performance Improvement, Learning Process and Support of Powerful Group took place. In Socio-Technical Regime level: Changes in Social Network, Changes in Technology and Changes in Rules. In Landscape level: Macro-Political Development, Socio-Economic Trends and Macro-Economic Trends took place in consecutive order.

Preference of User Groups on Facade Elements of Remodeled Factories in Korea

  • Liu, Yuanzhao;Park, Changbae
    • Architectural research
    • /
    • v.24 no.2
    • /
    • pp.29-40
    • /
    • 2022
  • The transition from manufacturing to service-based economies in highly developed societies during the post-industrial period resulted in the decline of the industrial landscape, leaving it abandoned or underutilized. In pursuit of revitalizing the obsolete industrial space, innovative design techniques based on adaptive reuse are applied to retrofit modern functions to create a new cultural space and preserve the historical, symbolic, and cultural importance of the abandoned industrial facilities. Design considerations based on facade redesign have proven to be one of the most adopted techniques that can help in recreating a new function for the vacant industrial buildings and integrating them into the present-day urban fabric. This paper examines the facade renovation elements used for the adaptive reuse of 15 abandoned industrial buildings presently used as multi-purpose facilities in South Korea. Through a questionnaire survey, this study analyzes the respondents' preference for different facade renovation elements in the 15 sites according to age and gender. The study found that both genders showed similar preference patterns between most elements. But on some elements, females were keener and expressed a stronger opinion than males. There were much more females than males who perceived color and material as the most important exterior elements. The findings of this study can be used for the adaptive reuse of industrial buildings according to user preferences for different facade renovation elements.

Effect of Alloying Elements on the Glass Forming Ability of Zr-Ti-Cu-Ni-X Alloys (Zr-Ti-Cu-Ni-X계 합금의 첨가원소에 따른 비정질 형성능)

  • Choi, Chul-Jin
    • Journal of Korea Foundry Society
    • /
    • v.21 no.5
    • /
    • pp.286-289
    • /
    • 2001
  • The glass formation behavior was investigated in the melt spun Zr-Ti-Cu-Ni-X (X=B, P and Si) ribbons. The magnitude of supercooled liquid region of Zr-Ti-Cu-Ni alloy increased with an addition of alloying element. The glass transition temperature and the crystallization temperature increased and the magnitude of supercooled liquid region decreased with increasing the content of alloying elements. The largest supercooled liquid region was observed in the Si containing alloy. This is believed to be due to the dense atom packing with the optimum atomic size ratio of constituent elements.

  • PDF

Microstructures and Elastic Moduli of the Alloys Containing the Biocompatible Alloying Elements (생체 친화적인 원소를 함유한 티타늄합금의 미세조직과 탄성계수)

  • Jeong, Hui-Won;Kim, Seung-Eon;Hyeon, Yong-Taek;Lee, Yong-Tae
    • 연구논문집
    • /
    • s.33
    • /
    • pp.157-165
    • /
    • 2003
  • New titanium alloys with a low elastic modulus have been developed for biomedical applications to avoid the stress shielding effect of the artificial prosthesis. The newly developed alloys contained the transition elements like Zr, Hf, Nb, Ta which were non-cytotoxicity elements and $\beta$ stabilizers. In the present paper the elastic moduli of Ti-xM containing Zr, Hf, Nb, Ta were evaluated by measuring the acoustic velocity (PEG). The effectiveness of the alloying elements for lowering the elastic modulus was investigated. In addition, the dominant factors for the low modulus were discussed. Ta was the most effective in lowering the elastic modulus of the alloys. The effectiveness of Hf was not acceptable for decreasing the elastic modulus. The dominant factor was the lattice parameter for Zr, and the poisson's ratio for Nb, Ta, respectively.

  • PDF