• Title/Summary/Keyword: constraint-based analysis

검색결과 482건 처리시간 0.025초

구속된 시스템 운동방정식의 수치해석에 관한 연구 (A Study on Numerical Analysis of Equation of Motion for Constrained Systems)

  • 은희창;정헌수
    • 소음진동
    • /
    • 제7권5호
    • /
    • pp.773-780
    • /
    • 1997
  • Using Generalized Inverse Method presented by Udwadia and Kalaba in 1992, we can obtain equations to exactly describe the motion of constrained systems. When the differential equations are numerically integrated by any numerical integration scheme, the numerical results are generally found to veer away from satisfying constraint equations. Thus, this paper deals with the numerical integration of the differential equations describing constrained systems. Based on Baumgarte method, we propose numerical methods for reducing the errors in the satisfaction of the constraints.

  • PDF

Performance Analysis of an Adaptive Link Status Update Scheme Based on Link-Usage Statistics for QoS Routing

  • Yang, Mi-Jeong;Kim, Tae-Il;Jung, Hae-Won;Jung, Myoung-Hee;Choi, Seung-Hyuk;Chung, Min-Young;Park, Jae-Hyung
    • ETRI Journal
    • /
    • 제28권6호
    • /
    • pp.815-818
    • /
    • 2006
  • In the global Internet, a constraint-based routing algorithm performs the function of selecting a routing path while satisfying some given constraints rather than selecting the shortest path based on physical topology. It is necessary for constraint-based routing to disseminate and update link state information. The triggering policy of link state updates significantly affects the volume of update traffic and the quality of services (QoS). In this letter, we propose an adaptive triggering policy based on link-usage statistics in order to reduce the volume of link state update traffic without deterioration of QoS. Also, we evaluate the performance of the proposed policy via simulations.

  • PDF

Grammatical Interfaces in Korean Honorification: A Constraint-based Perspective

  • Kim, Jong-Bok
    • 한국언어정보학회지:언어와정보
    • /
    • 제19권1호
    • /
    • pp.19-36
    • /
    • 2015
  • Honorific agreement is one of the main properties in languages like Korean, playing a pivotal role in appropriate communication. This makes the deep processing of honorific information crucial in various computational applications such as spoken language translation and generation. This paper shows that departing from previous literature, an adequate analysis of Korean honorification needs to involve a system that has access not only to morpho-syntax but to semantics and pragmatics as well. Along these lines, this paper offers a constraint-based HPSG analysis of Korean honorification in which the enriched lexical information tightly interacts with syntactic, semantic, and pragmatic levels for the proper honorific system.

  • PDF

Welding deformation analysis based on improved equivalent strain method to cover external constraint during cooling stage

  • Kim, Tae-Jun;Jang, Beom-Seon;Kang, Sung-Wook
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • 제7권5호
    • /
    • pp.805-816
    • /
    • 2015
  • In the present study, external restraints imposed normal to the plate during the cooling stage were determined to be effective for reduction of the angular distortion of butt-welded or fillet-welded plate. A welding analysis model under external force during the cooling stage was idealized as a prismatic member subjected to pure bending. The external restraint was represented by vertical force on both sides of the work piece and bending stress forms in the transverse direction. The additional bending stress distribution across the plate thickness was reflected in the improved inherent strain model, and a set of inherent strain charts with different levels of bending stress were newly calculated. From an elastic linear FE analysis using the inherent strain values taken from the chart and comparing them with those from a 3D thermal elasto-plastic FE analysis, welding deformation can be calculated.

양자화 제약 집합에 여과된 데이터를 투영하는 기법의 이론적 고찰 (Theoretical analysis of the projection of filtered data onto the quantization constraint set)

  • 김동식;박섭형
    • 한국통신학회논문지
    • /
    • 제21권7호
    • /
    • pp.1685-1695
    • /
    • 1996
  • The postprocessing of compressed images based on the projections onto convex sets and the constrained minimization imposes several constraints on the procesed data. The quantization constraint has been commonly used in various algorithms. Quantization is many-to-one mapping, by which all the dat in a quantization region are mapped to the corresponding representative level. The basic idea behind the projection onto the QCS(quantization constraint set) is to prevent the processed data from diverging from the original quantization region in order to redue the artifacts caused by filtering in postprocessing. However, there have been few efforts to analye the POQCS(projection onto the QCS). This paper analyzed mathematically the POQCS of filtered data from the viewpoint of minimizing the mean square error. Our analysis shows that a proper filtering technique followed by the POQCS can reduce the quantization distortion. In the conventional POQCS, the outside data of each quantization region are mapped into the corresponding boundary. Our analysis also shows that mappingthe outside data to the boundary of a subregion of the quantization region yields lower distortion than does the mapping to the boundary of the original region. In addition, several examples and discussions on the theory are introduced.

  • PDF

An Optimality-Based Analysis of Relative Positioning of Wh-related Prepositions in English

  • Han-gyoo, Khym
    • International Journal of Advanced Culture Technology
    • /
    • 제10권4호
    • /
    • pp.576-582
    • /
    • 2022
  • In this paper, we discuss the relative positioning of Wh-related English prepositions in a Wh-interrogative construction within the Optimality Theory [1-2]. By employing the two key constraints such as *Prep-Str and Align which are developed for the positioning of Wh-related prepositions from Romance languages such as French and Italian [3] and for the positioning of Wh-related prepositions from the middle English prose from 1500 to 1900 [4-6], and by slightly modifying the constraint hierarchy of *Prep-STR >>Align into **PrepSTR <<>>Align, Choi argues that his new theory can properly explain the unique behaviors of English Whrelated prepositions being able to take two 'optional' operations such as pied-piping and stranding to find legitimate landing sites in a Wh-interrogative construction [7]. However, this new analysis again reveals the following critical problems: (1) Unlike the 'light' English Wh-related prepositions which can two optional operations for legitimate landing sites in a Wh-interrogative construction, 'heavy' Wh-related English prepositions are not allowed to have such two options: they take just one option of pied-piping only. Thus, (2) his argumentation based on the existing constraints and the modified constraint hierarchy is neither general enough nor proper to explain the issue of the relative positioning for all English Wh-related preposition cases. To include such exceptional syntactic property of the 'heavy' preposition cases within the Optimality Theory, we suggest a new constraint of *HPrep-STR ranked at the highest position of the constraint hierarchy to disallow a 'heavy' or multi-syllabic Wh-related English preposition to stay alone at the end of a sentence. The new final hierarchy of constraints we suggest to explain the exceptional positioning of 'heavy' Wh-related prepositions together with the other 'light' Wh-related prepositions in English Wh-interrogative construction will be as follows: *HPrep-STR>>Align<<>>*Prep-STR.

Q&A 가상 커뮤니티에서 지속적인 지식 기여에 영향을 미치는 요인: 개인적 관여도의 조절효과를 중심으로 (Understanding the Continuance Intention of Knowledge Contribution in Q&A Virtual Communities: Focused on Moderating Effect of Personal Involvement)

  • 조려;정철호
    • Journal of Information Technology Applications and Management
    • /
    • 제28권6호
    • /
    • pp.117-132
    • /
    • 2021
  • Based on the core value of the Q&A community, the contribution of knowledge and information has a great impact on users' community evaluation. As a small social group, the relationships and interactions among community members are quickly formed through information technology. As such, the cognitive evaluation of the relationship between community members will have an impact on the intention of information contribution. This research builds on the previous research based on the social exchange theory and establishes a dual model of swift guanxi in examining the relationship between guanxi and continuous knowledge contribution. In the current study, 305 survey questionnaires were used and 249 valid questionnaires were used for analysis. The analysis results are as follows: First, information support has a positive impact on dedication-based swift guanxi. While hypothesis between information support and constraint-based swift guanxi was not be supported. Second, emotional support has a positive impact on the formation of swift guanxi from a dual perspective. Third, the swift guanxi from the dual perspective has a positive impact on the intention of continuous knowledge contribution. Finally, although personal involvement has an adjustment effect, it is a downward adjustment effect, hypotheses are not supported. The current study offers theoretical and practical implications in field of knowledge management, specifically knowledge contribution in the virtual community.

객체지향 데이터 모델을 이용한 다물체 동역학 해석 시스템 개발 (Development of a Multibody Dynamics Analysis System Using the Object-Oriented Data Model)

  • 박태원;송현석;서종휘;한형석;이재경
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2003년도 춘계학술대회 논문집
    • /
    • pp.1487-1490
    • /
    • 2003
  • In this paper, the application of object-oriented Data Model to develop a multibody dynamic system, called O-DYN, is introduced. Mechanical components, such as bodies, joints, forces are modeled as objects which have data and method by using object-oriented modeling methodology. O-DYN, a dynamic analysis system, based on the object-oriented modeling concept is made in C++. One example is analyzed through the O-DYN, It is expected that the analysis program or individual module constructed in this paper would be useful for mechanical engineers in predicting the dynamic responses of multibody systems and developing an analysis program

  • PDF

Optimal design using genetic algorithm with nonlinear inelastic analysis

  • Kim, Seung-Eock;Ma, Sang-Soo
    • Steel and Composite Structures
    • /
    • 제7권6호
    • /
    • pp.421-440
    • /
    • 2007
  • An optimal design method in cooperated with nonlinear inelastic analysis is presented. The proposed nonlinear inelastic method overcomes the difficulties due to incompatibility between the elastic global analysis and the limit state member design in the conventional LRFD method. The genetic algorithm used is a procedure based on Darwinian notions of survival of the fittest, where selection, crossover, and mutation operators are used to look for high performance ones among sections in the database. They are satisfied with the constraint functions and give the lightest weight to the structure. The objective function taken is the total weight of the steel structure and the constraint functions are load-carrying capacity, serviceability, and ductility requirement. Case studies of a planar portal frame, a space two-story frame, and a three-dimensional steel arch bridge are presented.

구조물의 효율적인 해석을 위한 모델 축소기법 연구 (A Model Reduction Method for Effective Analysis of Structures)

  • 박영창;황재혁
    • 한국항공운항학회지
    • /
    • 제14권1호
    • /
    • pp.28-35
    • /
    • 2006
  • Substructure coupling or component mode synthesis may be employed in the solution of dynamic problems for large, flexible structures. The model is partitioned into several subdomains, and a generalized Craig-Bampton representation is derived. In this paper the mode sets (normal modes, constraint modes) is employed for model reduction. A generalized model reduction procedure is described. Vaious reduction methods that use constraint modes is described in detail. As examples, a flexible structure and a 10 DOF damped system are analyzed. Comparison with a conventional reduction method based on a complete model is made via eigenpair and dynamic responses.

  • PDF