• 제목/요약/키워드: mathematic model

검색결과 85건 처리시간 0.024초

GMA 용접공정에서 용접부의 표면 및 이면의 온도분포 (Temperature distribution of top and back surface in GMA welding process)

  • 김영선;조형석
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.1408-1411
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    • 1996
  • In arc welding processes, because of the complexity and nonlinearity of heat transfer phenomena, it is often difficult to design an effective control system based upon an exact mathematic model. In this paper, we simulated the welding process for various welding conditions and positions to investigate the variations of temperature distribution for those cases. Those will be used as a preinformation for developing quality control system for arc welding process.

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Modeling and testing for hydraulic shock regarding a valve-less electro-hydraulic servo steering device for ships

  • Jian, Liao;Lin, He;Rongwu, Xu
    • International Journal of Fluid Machinery and Systems
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    • 제8권4호
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    • pp.318-326
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    • 2015
  • A valve-less electro-hydraulic servo steering device (short: VSSD) for ships was chosen as a study object, and its mathematic model of hydraulic shock was established on the basis of flow properties and force balance of each component. The influence of system structure parameters, changing rate of motor speed and external load on hydraulic shock strength was simulated by the method of numerical simulation. Experiment was designed to test the hydraulic shock mathematic model of VSSD. Experiment results verified the correctness of the model, and the model provided a correct theoretical method for the calculation and control of hydraulic shock of valve-less electro-hydraulic servo steering device.

The Mathematic Model of “Pressing Complexion”Differential Coefficient Countermeasure Decision for Collision-avoidance

  • Cai, Feng;Shi, Aiguo;Yang, Baozhang;Zhou, Lixin
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2001년도 Proceeding of KIN-CIN Joint Symposium 2001 on Satellite Navigation/AIS, lntelligence , Computer Based Marine Simulation System and VDR
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    • pp.81-87
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    • 2001
  • In this article, we have done some analysis about the collision-avoidance specialty of “pressing complexion” and “pressing danger”in the meet process of two boats, and offered a mathematic model of differential coefficient countermeasure decision for collision-avoidance, which adapt to the right complexion. The basal idea is, in the right condition whatever do the coming boat do, and our boat will always adept dynamic, continuous and the best countermeasure. When both the controlling capabilities of two boats have advantage and inferior position, we can working-out with the qualitative differential coefficient countermeasure.

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Degradation and mineralization of violet-3B dye using C-N-codoped TiO2 photocatalyst

  • Putri, Reza Audina;Safni, Safni;Jamarun, Novesar;Septiani, Upita;Kim, Moon-Kyung;Zoh, Kyung-Duk
    • Environmental Engineering Research
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    • 제25권4호
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    • pp.529-535
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    • 2020
  • The present study investigated the photodegradation of synthetic organic dye; violet-3B, without and with the addition of C-N-codoped TiO2 catalyst using a visible halogen-lamp as a light source. The catalyst was synthesized by using a peroxo sol-gel method with free-organic solvent. The effects of initial dye concentration, catalyst dosage, and pH solution on the photodegradation of violet-3B were examined. The efficiency of the photodegradation process for violet-3B dye was higher at neutral to less acidic pH. The kinetics reaction rate of photodegradation of violet-3B dye with the addition of C-N-codoped TiO2 followed pseudo-first order kinetics represented by the Langmuir-Hinshelwood model, and increasing the initial concentration of dyes decreased rate constants of photodegradation. Photodegradation of 5 mg L-1 violet-3B dye achieved 96% color removal within 240 min of irradiation in the presence of C-N-codoped TiO2 catalyst, and approximately 44% TOC was removed as a result of the mineralization.

Vidyanusa Mathematic Learning Systems Based on Digital Game by Balanced Design Approach

  • Ramdania, Diena Rauda;Prihatmanto, Ary Setijadi;Kim, Myong Hee;Park, Man-Gon
    • 한국멀티미디어학회논문지
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    • 제19권3호
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    • pp.603-611
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    • 2016
  • Educational games offer an opportunity to engage and inspire students to take an interest in every subject material in school. The "fun" obtain when playing games become a trigger for the use of games in learning. However, there are doubts whether the players actually learn while they are having fun. Vidyanusa is an Online Mathematics Education Game being developed by Crayonpedia Education Ecosystem in Indonesia. The learning goal of Vidyanusa is to engage junior high school students in learning mathematics. In this paper, we design the Vidyanusa game material Functions and Relations by using Balanced Design Approach. This approach has three models in succession; the Content Model outlines the purpose of the game, the Task Model maps out the mission, and the Evidence Model outlines student measurement. This paper will then discusses the quality of games produced in term of Usability factor for effective results and objective. The measurement of the game was carried out based on International Standard ISO/IEC 9126-1 FDIS about Software Quality Product.

스마트 기기 활용 시니어 수학 자료 개발 연구 (Study for Mathematics App development for Senior)

  • 고호경;이형주
    • 한국수학교육학회지시리즈E:수학교육논문집
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    • 제30권3호
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    • pp.309-333
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    • 2016
  • 본 고는 노인학습자 대상의 사용자 중심 설계에 바탕을 둔 앱 개발 연구의 일환으로, 시니어 수학 앱 개발 연구이다. 시니어 수학 앱에서 제공된 수학 콘텐츠는 '수리문해(Numeracy)'에 초점을 두었으며 노인 세대에 친숙한 소재와 활동적 요소를 도입하여 구성하였다. 수학 앱 개발을 위한 수학 콘텐츠와 사용자 인터페이스를 확정하기 위하여 9명의 노인학습자를 대상으로 교수 실험을 실시하였다. 또한 교수 실험 결과를 모니터링하기 위하여 CIPP 프로그램 평가모형을 활용하였다. 이에 따라 '교육목표', '요구분석', '교육환경', '커리큘럼', '학습내용', '학습 소재', '상호작용', '프로그램 관리', '지원환경', '만족도', '학습 결과', '학습의 지속가능성' 등의 요인을 점검하고 이에 대한 피드백에 따라 시니어 수학 앱을 개발하였다.

Modelling of effective irradiation swelling for inert matrix fuels

  • Zhang, Jing;Wang, Haoyu;Wei, Hongyang;Zhang, Jingyu;Tang, Changbing;Lu, Chuan;Huang, Chunlan;Ding, Shurong;Li, Yuanming
    • Nuclear Engineering and Technology
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    • 제53권8호
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    • pp.2616-2628
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    • 2021
  • The results of effective irradiation swelling in a wide range of burnup levels are numerically obtained for an inert matrix fuel, which are verified with DART model. The fission gas swelling of fuel particles is calculated with a mechanistic model, which depends on the external hydrostatic pressure. Additionally, irradiation and thermal creep effects are included in the inert matrix. The effects of matrix creep strains, external hydrostatic pressure and temperature on the effective irradiation swelling are investigated. The research results indicate that (1) the above effects are coupled with each other; (2) the matrix creep effects at high temperatures should be involved; and (3) ranged from 0 to 300 MPa, a remarkable dependence of external hydrostatic pressure can be found. Furthermore, an explicit multi-variable mathematic model is established for the effective irradiation swelling, as a function of particle volume fraction, temperature, external hydrostatic pressure and fuel particle fission density, which can well reproduce the finite element results. The mathematic model for the current volume fraction of fuel particles can help establish other effective performance models.

고등학생용 수학불안 요인 측정 도구 개발 및 타당도 검증 (Development of a Tool to Measure Math Anxiety Factors for High School Students and Validation of Validity)

  • 강양구;한선영
    • 한국수학교육학회지시리즈E:수학교육논문집
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    • 제36권2호
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    • pp.201-227
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    • 2022
  • 한국 고등학교 학생들에게 적합한 수학불안 요인 측정도구를 개발하기 위하여 요인 탐색, 문항 개발, 타당도 및 신뢰도 검증의 단계로 연구를 실시하였다. 이를 위하여 문헌분석을 통해 기 개발되어 사용되어온 문항을 수정 보완하고, 학생들을 대상으로 한 개방형 조사를 통해 사교육 및 수학 교수 방법에 대한 시대적 배경을 반영한 신규 문항을 추가하였다. 개발된 측정문항에 대한 탐색적 요인분석과 확인적 요인분석을 통해 타당도를 검증하였으며, 연구 결과, 수학교과의 특성에 기인하는 불안 요인이 구체화되었고, 모둠학습이나 발표수업 등과 같은 교수학습 방법 등이 반영되었다.

Parametric Body Model Generation for Garment Drape Simulation

  • Kim, Sungmin;Park, Chang-Kyu
    • Fibers and Polymers
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    • 제5권1호
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    • pp.12-18
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    • 2004
  • A parametric body model generation system has been developed. Using various mathematic and geometric algorithms of this system, a three-dimensionally scanned human body can be converted into a resizable body model. Once a parametric body model is formed, its size and shape can be modified instantaneously by providing appropriate anthropometric data. To facilitate the subsequent pattern arrangement process for garment drape simulation, a bounding box generation algorithm has been developed in this study. Also the model can be converted into a set of parametric surfaces that it can also be used for three-dimensional garment pattern design system.