• Title/Summary/Keyword: A state of the Art

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Feature Recognition: the State of the Art

  • JungHyun Han
    • Korean Journal of Computational Design and Engineering
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    • v.3 no.1
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    • pp.68-85
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    • 1998
  • Solid modeling refers to techniques for unambiguous representations of three-dimensional objects. Feature recognition is a sub-discipline focusing on the design and implementation of algorithms for detecting manufacturing information such as holes, slots, etc. in a solid model. Automated feature recognition has been an active research area in stolid modeling for many years, and is considered to be a critical component for CAD/CAM integration. This paper gives a technical overview of the state of the art in feature recognition research. Rather than giving an exhaustive survey, I focus on the three currently dominant feature recognition technologies: graph-based algorithms, volumetric decomposition techniques, and hint-based geometric reasoning. For each approach, I present a detailed description of the algorithms being employed along with some assessments of the technology. I conclude by outlining important open research and development issues.

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The History of Liquid Ear Acupuncture and the Current Scientific State of the Art

  • Litscher, Daniela;Litscher, Gerhard
    • Journal of Pharmacopuncture
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    • v.19 no.2
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    • pp.109-113
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    • 2016
  • This short review article presents a current overview of existing publications and scientific results regarding liquid (ear) acupuncture. The injection of liquids into defined acupuncture points of the ear is not a method commonly used in the Western world. The term liquid acupuncture has different definitions, which makes understanding each definition and differentiating one from the other difficult. General terms like pharmacopuncture, homeosiniatry, and liquid acupuncture, which all describe the method of injecting different kinds of drugs into a defined body acupuncture point, are used. This article presents the history of liquid acupuncture, as well as the current scientific state of the art, from the point of view of two European researchers. Some articles are discussed and a few practical examples are presented.

A Comparative Legal Study on the Non-Performance and Remedies under International Commercial Contract - Focusing on the CISG, PICC and PECL - (국제상사계약상불이행과 구제에 관한 비교 연구)

  • Shim, Chong-Seok
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.44
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    • pp.3-29
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    • 2009
  • The PECL have been drawn up by an independent body of experts from each member state of the european union under a project supported by the european commission and many other organizations. Salient features of the general provisions of the PECL, freedom of contract and pecta sunk servanda, good faith and fair dealing, most of the PECL are non-mandatory. The CISG uses the term fundamental breach in various setting. The concept of fundamental breach is a milestone in its remedial provisions. Its most important role is that it constitutes the usual precondition for the contract to be avoided(Art. 49., Art. 51., Art. 64., Art. 72., Art. 73). In addition, where the goods do not conform with the contract, a fundamental breach can give rise to a requirement to deliver substitute goods. Furthermore, a fundamental breach of contract by the seller leaves the buyer with all of his remedies intact, despite the risk having passed to him(Art. 70). Basically, PECL, PICC generally follows CISG, it was similar to all the regulation's platform though the terms and content sometimes differ. For example regarding to the non-performance and remedies, in the case of non-performance, that is the PECL/PICC term analogous to breach of contract as used in the CISG. Furthermore the PECL/PICC used fundamental non-performance refered to in PECL Art. 8:103 ; PICC Art. 7.1.1. correspond generally to the concept of fundamental breach referred to in CISG Art. 25. The main significance of the fundamental non-performance, in any systems, is to empower the aggrieved party to terminate the contract. The need for uniformity and harmony in international commercial contracts can be expected to lead to growth of international commerce subject to the CISG, PICC, and PECL. It is hoped that the present editorial remarks will provide guidance to improve understanding between the contractual party of different countries in this respect and following key-words.

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State-of-the-art of advanced inelastic analysis of steel and composite structures

  • Liew, J.Y. Richard
    • Steel and Composite Structures
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    • v.1 no.3
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    • pp.341-354
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    • 2001
  • This paper provides a state-of-the-art review on advanced analysis models for investigating the load-displacement and ultimate load behaviour of steel and composite frames subjected to static gravity and lateral loads. Various inelastic analysis models for steel and composite members are reviewed. Composite beams under positive and negative moments are analysed using a moment-curvature relationship which captures the effects of concrete cracking and steel yielding along the members length. Beam-to-column connections are modeled using rotational spring. Building core walls are modeled using thin-walled element. Finally, the nonlinear behaviour of a complete multi-storey building frame consisting of a centre core-wall and the perimeter frames for lateral-load resistance is investigated. The performance of the total building system is evaluated in term of its serviceability and ultimate limit states.

A State-of-the-Art of Probabilistic Seismic Fragility Analysis of Critical Structure (핵심 구조물의 확률론적 지진취약도 분석: 기술현황)

  • 조양희
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2000.04a
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    • pp.226-232
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    • 2000
  • Seismic probabilistic risk assessment(RA) rather than deterministic assessment provides more valuable information and insight for resolving seismic safety issues in nuclear power plant design. In the course of seismic PRA seismic fragility analysis is the most significant and essential phase especially for structural or mechanical engineers. Lately the seismic fragility analysis is taken as a useful tool in general structural engineering as well. A systemized and synthesized procedure or technology related to seismic fragility analysis of critical industrial facilities reflecting the unique experiences and database in Korea is urgently required. This paper gives a state-of-the-art reviews of PRA and briefly summarizes the technologies related to PRA and seismic fragility analysis before developing an unique technology considering characteristics of Korean database. Some key items to be resolved theoretically or technically are extracted and presented for the future research.

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State-of-the-art of Pier Scour Prediction for Design Application

  • Choi, Gye-Woon;Ahn, Sang-Jin;Kang, Kwan-Won
    • Korean Journal of Hydrosciences
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    • v.2
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    • pp.39-59
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    • 1991
  • Scour at bridge pier is a complicated three-dimensional problem involving interaction of fluld force on movable aid nonuniformily distributed sand grains. Although several analytical solution approaches, experimental research and field investigations for scout at piers have been conducted, no comprehensive and universally acceptable solution is so far available. Even though many methods and equations for predicting scour at piers are available in the literature, hydraulic and/or bridge design engineers are often at a loss over which method or equation is applicable for the specific bridge sites. To provide better understanding about scour phenomena and better predicting of scour at piers, intensive research is conducted through comprehensive review of published literature. Based on the research the state-of-the-art of pier scour prediction for design application is provided as a design guide for practicing engineers in this field. Recommendations for applying aggradation and degradation, contraction scour, and local scour prediction methods or equations are suggested. It is hoped that this paper may provide good information for the prediction of scour at piers.

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State-of-art on Its Application and Errors in Pushover Analysis of Building Structures (건축물의 내진설계에서 정적 비선형해석의 적용과 오차에 대한 고찰)

  • Jun, Dae-Han;Song, Ho-San
    • Journal of Korean Association for Spatial Structures
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    • v.5 no.1 s.15
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    • pp.99-105
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    • 2005
  • The pushover analysis is becoming a popular tool for seismic design of building structures. In this paper the state-of-art on static nonlinear analysis of building structures is presented with the emphasis on the effects of analysis parameters; i. e., lateral load patterns, modeling of members, and analysis computer programs. The analysed results may have variation even if a same structure is analysed. This paper is to investigate how large the variation is and what the main causes of the variation are. The difference of analysed results, the resultant variation of lateral story shear force and flexural strength of structural members are discussed. The pushover analysis procedure are routinely used in the seismic design of building structures, but some problems must yet be clarified, such as the effects to evaluate the parameters of analysis on the basis of a lateral load patterns and modeling of members.

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State-of-art on Its Application and Errors in Pushover Analysis of Building Structures (건축물의 내진설계에서 정적 비선형해석의 적용과 오차에 대한 고찰)

  • Jun, Dae-Han;Song, Ho-San
    • 한국공간정보시스템학회:학술대회논문집
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    • 2004.05a
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    • pp.103-110
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    • 2004
  • The pushover analysis is becoming a popular tool for seismic design of building structures. In this paper the state-of-art on static nonlinear analysis of building structures is presented with the emphasis on the effects of analysis parameters; i. e., lateral load patterns, modeling of members, and analysis computer programs. The analysed results may have variation even if a same structure is analysed. This paper is to investigate how large the variation is and what the main causes of the variation are. The difference of analysed results, the resultant variation of lateral story shear force and flexural strength of structural members are discussed. The pushover analysis procedure are routinely used in the seismic design of building structures, but some problems must yet be clarified, such as the effects to evaluate the parameters of analysis on the basis of a lateral load patterns and modeling of members.

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The State of the Art in BIPV Technology (건물일체형 태양광 발전 (BIPV) 기술 동향)

  • Yoon, Jong-Ho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.27 no.1
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    • pp.1-7
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    • 2014
  • The current downturn of BIPV sector has an enormous potential to rebound and expand into the PV sector for construction market in the foreseeable future. Solar technology has already gained a significant market due to lack of natural resources in the Korean domestic market. Given the technical infrastructure of state-of-the-art fusion technology, the competitiveness of software-driven BIPV market in the world can be ver attractive and have the potential to develop as a key national technology. To do this, from the viewpoint of complexity, technical R&D, national political aspect, social aspect, economic aspect and institutional support systems need to be parallelly formulated. A dedicated BIPV sector has not yet been established, especially policy and institutional framework have very crucial impact on the establishment of BIPV sector.

A Study on the State of Art and International Cooperation in the Field of Mechanical Engineering by Delphi Method (Delphi기법에 의한 기계공학기술의 수준평가 및 국제 기술협력기반에 관한 연구)

  • 권영주
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.04a
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    • pp.169-175
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    • 1996
  • We provide a fudamental set of information on technologies in the area of mechanical engineering to draw action plans for intermationalization of the National R&D activites. First, we design and use a modified Delphi method to evaluate levels of our technological capabilities and developed countries' as well. We investigate technology acquistion methodolgies, technology characteristcs and various aspects of international cooperation in terms of technology. Secondly, we analyze final responses of participants (i.e,. the third round results of Delphi method) tosee the correlation between various factors in developing mechanical engineering technologies through international cooperation. The technology classification used in this research is developed by STEPI (Science and Technology Policy Institute).

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