• 제목/요약/키워드: object-orientation

검색결과 307건 처리시간 0.031초

요소 독립성이 유지되는 반복해법에 의한 객체지향 유한요소모델 개발 (Development of an Object-oriented Finite Element Model through Iterative Method Ensuring Independency of Elements)

  • 이한귀;김태곤;이정재
    • 한국농공학회논문집
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    • 제54권2호
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    • pp.115-125
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    • 2012
  • Application of the Object-oriented Programming (OOP) method to the Finite Element Model (FEM) program has various strengths including the features of encapsulation, polymorphism and inheritance. However, this technique should be based upon a premise that the independency of the object method and data to be used is guaranteed. By attempting to apply the OOP to the FEM, existing researches go against the independency of the OOP which is an essential feature of the method. The reason is this: existing researches apply the OOP to modules in accordance with analysis procedures, although the data to be used is classified as an element unit in the FEM. Therefore, the required independency cannot be maintained as whole stiffness matrices and boundary conditions are combined together. Also, solutions are sought from analysis module after data is regrouped at the pre-processor, and their results are analyzed during the post-processor. As this is similar to a batch processing, it cannot use data at analysis, and recalculation should be done from the beginning if any condition is changed after the analysis is complete, which are limitations of the existing researches. This research implemented the Object-orientation of elements so that the three features of the OOP (i.e. encapsulation, polymorphism and inheritance) can be guaranteed and their independency maintained as a result. For this purpose, a model called 'Object-oriented Finite element Model ensuring the Independency of Elements (OFMIE)', which enables the analysis of targets through mutual data exchanges within instance, was developed. In conclusion, the required independency was achieved in the instance of the objected elements and the analysis results of previous conditions could be used for the analysis after changes. The number of repetitive calculations was reduced by 75 per cent through this gradual analysis processes.

삼면반사체를 이용한 6자유도 미소 변위 측정 (Measurement of Fine 6-DOF Displacement using a 3-facet Mirror)

  • 박원식;조형석;변용규;박노열
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.50-50
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    • 2000
  • In this paper, a new measuring system is :proposed which can measure the fine 6-DOF displacement of rigid bodies. Its measurement principle is based on detection of laser beam reflected from a specially fabricated mirror that looks like a triangular pyramid having an equilateral cross-sectional shape. The mirror has three lateral reflective surfaces inclined 45$^{\circ}$ to its bottom surface. We call this mirror 3-facet mirror. The 3-facet mirror is mounted on the object whose 6-DOF displacement is to be measured. The measurement is operated by a laser-based optical system composed of a 3-facet mirror, a laser source, three position-sensitive detectors(PSD). In the sensor system, three PSDs are located at three corner points of a triangular formation, which is an equilateral triangular formation tying parallel to the reference plane. The sensitive areas of three PSDs are oriented toward the center point of the triangular formation. The object whose 6-DOF displacement is to be measured is situated at the center with the 3-facet mirror on its top surface. A laser beam is emitted from the laser source located at the upright position and vertically incident on the top of the 3-fatcet mirror. Since each reflective facet faces toward each PSD, the laser beam is reflected at the 3-facet mirror and splits into three sub-beams, each of which is reflected from the three facets and finally arrives at three PSDs, respectively. Since each PSD is a 2-dimensional sensor, we can acquire the information on the 6-DOF displacement of the 3-facet mirror. From this principle, we can get 6-DOF displacement of any object simply by mounting the 3-facet mirror on the object. In this paper, we model the relationship between the 6-DOF displacement of the object and the outputs of three PSDs. And, a series of simulations are performed to demonstrate the effectiveness of the proposed method. The simulation results show that the proposed sensing system can be an effective means of obtaining 3-dimensional position and orientation of arbitrary objects.

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Classes in Object-Oriented Modeling (UML): Further Understanding and Abstraction

  • Al-Fedaghi, Sabah
    • International Journal of Computer Science & Network Security
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    • 제21권5호
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    • pp.139-150
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    • 2021
  • Object orientation has become the predominant paradigm for conceptual modeling (e.g., UML), where the notions of class and object form the primitive building blocks of thought. Classes act as templates for objects that have attributes and methods (actions). The modeled systems are not even necessarily software systems: They can be human and artificial systems of many different kinds (e.g., teaching and learning systems). The UML class diagram is described as a central component of model-driven software development. It is the most common diagram in object-oriented models and used to model the static design view of a system. Objects both carry data and execute actions. According to some authorities in modeling, a certain degree of difficulty exists in understanding the semantics of these notions in UML class diagrams. Some researchers claim class diagrams have limited use for conceptual analysis and that they are best used for logical design. Performing conceptual analysis should not concern the ways facts are grouped into structures. Whether a fact will end up in the design as an attribute is not a conceptual issue. UML leads to drilling down into physical design details (e.g., private/public attributes, encapsulated operations, and navigating direction of an association). This paper is a venture to further the understanding of object-orientated concepts as exemplified in UML with the aim of developing a broad comprehension of conceptual modeling fundamentals. Thinging machine (TM) modeling is a new modeling language employed in such an undertaking. TM modeling interlaces structure (components) and actionality where actions infiltrate the attributes as much as the classes. Although space limitations affect some aspects of the class diagram, the concluding assessment of this study reveals the class description is a kind of shorthand for a richer sematic TM construct.

신유학(新儒學), 장횡거(張橫渠)의 기일원론(氣一元論)과 이동원(李東垣)의 내상학설(內傷學說) (Neo-confucianism(新儒學), Zhang Heng-qu(張橫渠)'s Qi-monism(氣一元論) and Li Dong-yuan(李東垣)'s Theory of Internal Injury(內傷學說))

  • 이용범
    • 대한한의학원전학회지
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    • 제26권3호
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    • pp.11-18
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    • 2013
  • Objective : This paper was designed to confirm the relation between Li Dong-yuan(李東垣)'s theory of internal injury(內傷學說) and Neo-confucianism(新儒學)'s academic orientation, particularly Zhang Heung-qu(張橫渠)'s 'Qi-monism(氣一元論)'. Method : Through a comparative literature review, I searched for the commonality between Li Dong-yuan(李東垣)'s theory of internal injury(內傷學說) and Neo-confucianism(新儒學)'s academic orientation, particularly Zhang Heung-qu(張橫渠)'s 'Qi-monism(氣一元論)', and also examined the difference in the meaning of 'Primordial Qi(元氣)' in Qi-monism and that Lee Dong-yuan proposed. Result & Conclusion : The central theme of Neo-confucianism, 'Staying on the Golden Path(允執厥中)', has a commonality with Li Dong-yuan's theory of internal injury that emphasized Primordial Qi, and the concepts of "Great Vacuity as Qi(太虛卽氣)", "Two Properties Inherent in a Single Object(一物兩體)", and "the Nature of Acquired Disposition(氣質之性)" have commonality with the concepts of "The Given from the Vacuity of Natural World(所受於天)", Up & Down Movement(升降運動), and Yin Fire(陰火) of Primordial Qi in Li Dong-yuan's theory of internal injury respectively. However, the concept of Primordial Qi in the Theory of Qi-monism refers to the building blocks of all things in the universe, whereas the concept of Primordial Qi that Li Dong-yuan proposed has no meaning of component of body but driving force that maintains the phenomenon of life.

Multi-camera System Calibration with Built-in Relative Orientation Constraints (Part 2) Automation, Implementation, and Experimental Results

  • Lari, Zahra;Habib, Ayman;Mazaheri, Mehdi;Al-Durgham, Kaleel
    • 한국측량학회지
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    • 제32권3호
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    • pp.205-216
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    • 2014
  • Multi-camera systems have been widely used as cost-effective tools for the collection of geospatial data for various applications. In order to fully achieve the potential accuracy of these systems for object space reconstruction, careful system calibration should be carried out prior to data collection. Since the structural integrity of the involved cameras' components and system mounting parameters cannot be guaranteed over time, multi-camera system should be frequently calibrated to confirm the stability of the estimated parameters. Therefore, automated techniques are needed to facilitate and speed up the system calibration procedure. The automation of the multi-camera system calibration approach, which was proposed in the first part of this paper, is contingent on the automated detection, localization, and identification of the object space signalized targets in the images. In this paper, the automation of the proposed camera calibration procedure through automatic target extraction and labelling approaches will be presented. The introduced automated system calibration procedure is then implemented for a newly-developed multi-camera system while considering the optimum configuration for the data collection. Experimental results from the implemented system calibration procedure are finally presented to verify the feasibility the proposed automated procedure. Qualitative and quantitative evaluation of the estimated system calibration parameters from two-calibration sessions is also presented to confirm the stability of the cameras' interior orientation and system mounting parameters.

푸리에 표현자의 크기와 회전 불변 특징을 에지에 대한 3차원 정보에 응용한 고효율의 물체 인식 (High Performance Object Recognition with Application of the Size and Rotational Invariant Feature of the Fourier Descriptor to the 3D Information of Edges)

  • 왕실;진홍신;이준호;임해평;김형석;김종만
    • 전자공학회논문지CI
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    • 제45권6호
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    • pp.170-178
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    • 2008
  • 3 차원 정보로부터 정확한 에지를 추출하고 푸리 변환하여 물체를 인식할 수 있는 고 효율의 물체 인식방법을 제안하였다. 물체의 윤곽은 인식에 유용한 많은 정보를 포함하고 있지만, 정확한 윤곽정보를 얻기가 어려우며, 정확한 윤곽정보를 얻었다고 하더라도 물체의 크기나 방향 마다 윤곽이 달라지기 때문에 물체 인식에 획기적 대안으로 활용되지 못하고 있다. 제안한 물체 인식 알고리즘은 1) 레이저 스캔 디바이스를 사용하여 얻는 3 차원 물체정보로부터 정밀한 물체 윤곽을 획득하고 2) 크기 및 회전 불변한 푸리에 표시 자를 이용하여 윤곽을 표현함으로써, 필요 데이터 베이스의 크기를 대폭 줄인다. 이렇게 얻어진 물체에 대한 푸리에 표식자 정보는 미리 준비된 푸리에 표식자 데이터 베이스로부터 최적 정합되는 물체를 찾아 인식한다. 이 알고리즘은 MPEG7 Part B의 방대한 영상 데이터 베이스를 대상으로 실험하였으며, 그에 대한 결과를 논문에 포함시켰다.

Homogeneous Transformation Matrix의 곱셈을 위한 병렬구조 프로세서의 설계 (A Parallel-Architecture Processor Design for the Fast Multiplication of Homogeneous Transformation Matrices)

  • 권두올;정태상
    • 대한전기학회논문지:시스템및제어부문D
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    • 제54권12호
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    • pp.723-731
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    • 2005
  • The $4{\times}4$ homogeneous transformation matrix is a compact representation of orientation and position of an object in robotics and computer graphics. A coordinate transformation is accomplished through the successive multiplications of homogeneous matrices, each of which represents the orientation and position of each corresponding link. Thus, for real time control applications in robotics or animation in computer graphics, the fast multiplication of homogeneous matrices is quite demanding. In this paper, a parallel-architecture vector processor is designed for this purpose. The processor has several key features. For the accuracy of computation for real application, the operands of the processors are floating point numbers based on the IEEE Standard 754. For the parallelism and reduction of hardware redundancy, the processor takes column vectors of homogeneous matrices as multiplication unit. To further improve the throughput, the processor structure and its control is based on a pipe-lined structure. Since the designed processor can be used as a special purpose coprocessor in robotics and computer graphics, additionally to special matrix/matrix or matrix/vector multiplication, several other useful instructions for various transformation algorithms are included for wide application of the new design. The suggested instruction set will serve as standard in future processor design for Robotics and Computer Graphics. The design is verified using FPGA implementation. Also a comparative performance improvement of the proposed design is studied compared to a uni-processor approach for possibilities of its real time application.

공동주택 단지의 주동형식에 따른 냉난방 에너지 및 외기냉방 효과 분석 (An Analysis of Heating and Cooling Energy and Effect on Outdoor Air Cooling according to Building Type of Apartment Complex)

  • 노지웅
    • 한국태양에너지학회 논문집
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    • 제34권4호
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    • pp.31-38
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    • 2014
  • This study makes three apartment building complex an object of analyzing representative building types and energy consumption rate of house holds, and effect of outdoor air cooling. Recently created apatrment complex is composed of very various types of building, plan, and orientation etc. But, it is difficult to remark conclusively that these various types of buildings are designed energy-effectively. Because architects are hard to find useful energy design guideline for decision making. By the preceding study, the present condition and problem about this subject is grasped, apartment building types were examined and representative types were extracted. In this study, energy simulation was conducted, and the effect to outdoor air cooling was analyzed about representative types of the subject apartment complex. It is expected that this analysed results will be basic data for the more integrated study. Research consequence can be summarized as follow: 1) Besides solar gain, household layout of building, orientation, and plan etc. effects compositively on energy consumption rate. 2) The effect of ourdoor air cooling in building of tower type can be improved by arranging households appropriately.

Design of an Absolute Location and Position Measuring System for a Mobile Robot

  • Kim, Dong-Hwan;Park, Young-Chil;Hakyoung Chung
    • Journal of Mechanical Science and Technology
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    • 제15권10호
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    • pp.1369-1379
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    • 2001
  • This paper focuses on a development of a sensor system measuring locations of a vehicle to localize a mobile robot while it tracks on the track (location sensor) . Also it focuses on a system configuration identifying the vehicle's orientation and distance from the object while it is stationary at certain station (position sensor) . As for the location sensor it consists of a set of sensors with a combined guiding and counting sensor, and an address-coded sensor to localize the vehicle while moving on the rail. For the position sensor a PSD (Position Sensitive Device) sensor with photo-switches sensor to measure the offset and orientation of the vehicle at each station is introduced. Both sensor systems are integrated with a microprocessor as a data relay to the main computer controlling the vehicle. The location sensor system is developed and its performance for a mobile robot is verified by experiments. The position measuring system is proposed and is robust to the environmental variation. Moreover, the two kinds of sensor systems guarantee a low cost application and high reliability.

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Diagrammatic Formalism for Complex Systems: More than One Way to Eventize a Railcar System

  • Al-Fedaghi, Sabah
    • International Journal of Computer Science & Network Security
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    • 제21권2호
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    • pp.130-141
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    • 2021
  • This paper is in the intersection of software engineering and system engineering, two intimately intertwined disciplines. A dominating theme in this paper is the integral conceptualization of systems at large, as well as an underlying concern with software systems. In the software development life cycle, challenges still exist in translating requirements into a design artifact and then into an implementation (e.g., coding), then validating the results. From our perspective, software engineering requires an integrating paradigm toward a unified modeling orientation. Many methodologies, languages, and tools exist for facilitating system development processes. This paper is a venture into project development. To focus the materials, we concentrate on Harel's novel (and classic) development environment, which integrates a scenario-based engineering object orientation and statecharts through developing a railcar system. The railcar system is used as a detailed sample of translating requirements into a design artifact and then into an implementation, then validating the result. The project is re-cased as a single integrated modeling endeavor to be contrasted with the scenario and statecharts' development. The result of this scheme is an enriched understanding through experimenting with and contrasting various development methods of software projects.