• Title/Summary/Keyword: Model-referenced control

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Development of a Portable Multi-sensor System for Geo-referenced Images and its Accuracy Evaluation (Geo-referenced 영상 획득을 위한 휴대용 멀티센서 시스템 구축 및 정확도 평가)

  • Lee, Ji-Hun;Choi, Kyoung-Ah;Lee, Im-Pyeong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.28 no.6
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    • pp.637-643
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    • 2010
  • In this study, we developed a Portable Multi-sensor System, which consists of a video camera, a GPS/MEMS IMU and a UMPC to acquire video images and position/attitude data. We performed image georeferencing based on the bundle adjustment without ground control points using the acquired data and then evaluated the effectiveness of our system through the accuracy verification. The experimental results showed that the RMSE of relative coordinates on the ground point coordinates obtained from our system was several centimeters. Our system can be efficiently utilized to obtain the 3D model of object and their relative coordinates. In future, we plan to improve the accuracy of absolute coordinates through the rigorous calibration of the system and camera.

EJB-based Workflow Model Data Management Mechanism (EJB 기반의 워크플로우 모델 데이터 관리 기술)

  • 김민홍
    • Journal of the Korea Computer Industry Society
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    • v.5 no.1
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    • pp.19-28
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    • 2004
  • The major problems in workflow system which controls business process arise with the difficulty of managing a vast volume of data. In this paper, a more reasonable method to manage workflow data is proposed after analyzing the data being used in workflow system. The data used in workflow system can be classified to model data, control data, workitem data and relevant data. The prime accent is placed on the workflow model data, as the model data is normally consistent and referenced more frequently that if the data is used efficiently, it is anticipated to give a good performance to workflow system. Relying on an intensive study, this paper designs and develops a model data system. This model data system is based on memory and manages versions, consistency, dynamic modification, and etc

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A Fast Generation Method of CAM Model for Machining of Jet Engines Using Shape Search (형상 검색을 이용한 제트엔진 절삭가공을 위한 빠른 CAM 모델 생성 방법)

  • Kim, Byung Chul;Song, Ilhwan;Shin, Suchul
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.40 no.3
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    • pp.327-336
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    • 2016
  • Manufacturers of aircraft engines have introduced computer-aided manufacturing (CAM) software to operate and control computerized numerical control (CNC) machine tools. However, the generation of a CAM model is a time consuming and error-prone task since machining procedure and operational details are manually defined. For the automatic generation of a CAM model, feature recognition techniques have been widely studied. However, their recognition coverage is limited so that complex shapes such as a jet engine cannot be fully developed. This study presents a novel approach to quickly generate a CAM model from a CAD model using shape search techniques. Once an operator sets a machining operation as a reference operation, the same shapes as the shapes referenced by the operation are searched. The reference operation is copied to the positions of the searched shapes. The proposed method was verified through experiments with a jet engine compressor case.

A Study on Applying The DO-178C to The Control SW Development of The Military Aircraft Intercom Based on CMMI (CMMI 기반 군 항공기 인터콤 탑재용 제어 소프트웨어 개발에 대한 DO-178C 적용 연구)

  • Yoon, In-Bok
    • Journal of IKEEE
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    • v.19 no.3
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    • pp.415-423
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    • 2015
  • The DO-178C guide, which is referenced as the software development guide when a certification of the airworthiness in the commercial airplane is acquired by FAA in US, is recently referenced for the local military aircraft airworthiness. This indicates that when the auditor of the military aircraft airworthiness looks over the software development documents, the auditor reviews if all of the documents are verified in accordance with the DO-178C guide. However, when we developed the military aircraft intercom, We developed its control software in accordance with the CMMI level 3, since there were no requirements for the compliance of the DO-178C guide. Therefore, When we consider the airworthiness of this intercomm system, The analysis for how much the software development based on the CMMI level 3 is different from the DO-178C guide is needed to prepare the essential software documents additionally. Thus, This study analyzes the differences between CMMI level 3 and DO-178C guide and provides that which data on the CMMI level 3 is necessary for the compliance of the aircraft airworthiness comparing with the DO-178C. The analyzed result can be applied at the software development of the other military aircraft avionics equipment based on the CMMI model environment considering the compliance of the military aircraft airworthiness.

Validating Dozer Productivity Computation Models (도저 생산성 연산모델 비교 연구)

  • Kim, Ryul-Hee;Park, Young-Jun;Lee, Dong-Eun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.39 no.4
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    • pp.531-540
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    • 2019
  • Existing dozer productivity computation models use different input variables, formulas, productivity correction factors, and experimental data source. This paper presents a method that characterizes the productivity outputs obtained by the PLS model and the Caterpillar model that are accepted as industry standards. The method identifies the input variables to be collected from the site, the performance charts to be referenced, and the formulas and implements them in a single computational tool. This study verifies that the PLS model may replace the manual computational process of Caterpillar model by eliminating reliance on graphics manipulation. Replacing the Caterpillar model with the PLS model and implementing the process as a function contributes to assess the productivity of a dozer timely by encouraging to utilize real-time information collected directly from the site. This study allows researchers and practitioners to effectively deal with the values of productivity correction factors collected from the job site and to control the productivity. The practicality and effectiveness of the method have been validated by applying to a project case.

Analysis of fast pressure control by the Ziegler-Nichols method for a transport module of a high vacuum cluster tool (고진공 클러스터 장비의 반송모듈에 적용된 Ziegler-Nichols 방법에 의한 고속 압력제어에 관한 해석)

  • 장원익;이종현;백종태
    • Journal of the Korean Vacuum Society
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    • v.5 no.4
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    • pp.284-291
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    • 1996
  • We have implemented a fast pressure control system for the transport chamber of a high vacuum cluster tool for advance semiconductor fabrication and evaluated its performance. To overcome the typically slow response of mass flow controllers, the modified experimental method is used very effectively to optimize the pressure control procedure. We successfully obtained quite fast pressure control by adjusting the starting time and eht tuning constants by the Ziegler-Nichols method. In the transport pressure $10\times 10^{-5}$ torr, actual pressure control starts from 4 sec after an initial gas load of 2.1 sccm. As a result, optimum conditions for the tuning constants are the rise rate of 0.02 torr/sec, the lag time of 0.15 sec, and the sampling period of 0.5 sec. Then the settling time is about 9 sec within about $\pm$0.5% for the referenced value. This settling time is enhanced above 75 percents in comparison with conventional experimental method. To account for the experimental effects observed, a theoretical model was developed. This experimental result has a tendency to fit with the theoretical result of $\omega$=-1.0.

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Mathematical Modeling for the Physical Relationship between the Coordinate Systems of IMU/GPS and Camera (IMU/GPS와 카메라 좌표계간의 물리적 관계를 위한 수학적 모델링)

  • Chon, Jae-Choon;Shibasaki, R.
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.26 no.6
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    • pp.611-616
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    • 2008
  • When extracting geo-referenced 3D data from cameras mounted on Mobile Mapping Systems, one of important properties for accuracy of extracted data is the alignment of the relative translation(lever-arm) and rotation(bore-sight) between the coordinate systems of Inertial Measurement Unit(IMU)/Ground Positioning System(GPS) and cameras. Since the conventional method calculates absolute camera orientation using ground control points (GCP), the alignment is determined in one Coordinated System (GPS Coordinated System). It basically require GCP. We proposed a mathematical model for the alignment using the initially uncoupled data of cameras and IMU/GPS without GCPs.

A real-time hybrid testing method for vehicle-bridge coupling systems

  • Guoshan Xu;Yutong Jiang;Xizhan Ning;Zhipeng Liu
    • Smart Structures and Systems
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    • v.33 no.1
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    • pp.1-16
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    • 2024
  • The investigation on vehicle-bridge coupling system (VBCS) is crucial in bridge design, bridge condition evaluation, and vehicle overload control. A real-time hybrid testing (RTHT) method for VBCS (RTHT-VBCS) is proposed in this paper for accurately and economically disclosing the dynamic performance of VBCSs. In the proposed method, one of the carriages is chosen as the experimental substructure loaded by servo-hydraulic actuator loading system in the laboratory, and the remaining carriages as well as the bridge structure are chosen as the numerical substructure numerically simulated in one computer. The numerical substructure and the experimental substructure are synchronized at their coupling points in terms of force equilibrium and deformation compatibility. Compared to the traditional iteration experimental method and the numerical simulation method, the proposed RTHT-VBCS method could not only obtain the dynamic response of VBCS, but also economically analyze various working conditions. Firstly, the theory of RTHT-VBCS is proposed. Secondly, numerical models of VBCS for RTHT method are presented. Finally, the feasibility and accuracy of the RTHT-VBCS are preliminarily validated by real-time hybrid simulations (RTHSs). It is shown that, the proposed RTHT-VBCS is feasible and shows great advantages over the traditional methods, and the proposed models can effectively represent the VBCS for RTHT method in terms of the force equilibrium and deformation compatibility at the coupling point. It is shown that the results of the single-degree-of-freedom model and the train vehicle model are match well with the referenced results. The RTHS results preliminarily prove the effectiveness and accuracy of the proposed RTHT-VBCS.

Application model research on visualizing anti-inflammation effects by using the virtual cell (가상세포를 활용한 항염증 효능 응용모델 연구)

  • Kim, Chul;Yea, Sang-Jun;Kim, Jin-Hyun;Kim, Sang-Kyun;Jang, Hyun-Chul;Kim, An-Na;Nam, Ky-Youb;Song, Mi-Young
    • Herbal Formula Science
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    • v.18 no.2
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    • pp.227-239
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    • 2010
  • Objective : The purpose of this study was to develop the simulator which can analyze the anti-inflammatory effects of herbs based on e-cell, or the virtual cell. Method : We have ensured the medical herbs and its active compounds by investigating the oriental medicine records and NBCI(Biomedicine database). Also we have developed the web-based search system for confirming database related to anti-inflammation. We have researched the cell signal pathway related with inflammatory response control and established the mathematical model of herb interaction on selected signal pathway in e-cell. Finally we have developed the prototype which can confirm the result of this model visibly. Results : We constructed the database of 62 cases of anti-inflammatory active compounds in 61 cases of medical herbs which have been known anti-inflammation effects in the paper, 16 cases of inflammatory factors, 10 cases of signal pathways related with inflammatory response and 6,834 cases of URL(Uniform Resource Locator) of referenced papers. And we embodied the web-based research system, which can research this database. User can search basic and detailed information of medical plants related with anti-inflammatory by using information system. And user can acquire information on an active compounds, a signal pathway and a link URL of related paper. Among investigated ten pathways, we selected NF-${\kappa}B$, which plays important role in activation of immune system, and we searched the mechanisms of actions of proteins which could be components of this pathway. We reduced total network into IKK-$I{\kappa}B$ - NF-${\kappa}B$, and completed mathematic modeling by using ordinary differential equations and response variables of $I{\kappa}B-NF-{\kappa}B$ signaling model network which is suggested by Baltimore Group. We designed OED(Ordinary Differential Equation) for response of IKK, $I{\kappa}B$, $NF-{\kappa}B$ in e-cell's cytoplasm and nucleus, and measured whether an active compound of medicinal plants which is inputted by an user would have a anti-inflammation effects in obedience to change in concentration over time. The proposed model was verified by using experimental results of the papers which are listed on NCBI.

Characteristics of Modeling of Experiment in Case Analysis of Students' Open Inquiry and its Meaning on Science Education (학생의 자유 탐구 활동의 사례 분석을 통해 본 실험 모델링의 특징과 과학교육적 의미)

  • Kim, Kwan-Young;Lee, Jong-Hyeok;Choi, Jinhyeon;Jeon, Sang-Hak;Lee, Sun-Kyung
    • Journal of The Korean Association For Science Education
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    • v.42 no.2
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    • pp.201-214
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    • 2022
  • The purpose of this study is to examine the characteristics of model of the experiment in students' open inquiry. The research is a reinterpretation of the data collected from the performance of a three-year research project under the theme of 'school science inquiry' the perspective of model of the experiment. The inquiry activities of a focus group made up of four students have been recorded seven times. The recorded files and transcribed copies were analyzed according to interpretive methods. Students' activities were divided into three modeling of the experiment units, considering the modeling unit that includes the process of starting from the problem until it gets solved. The results of the study include illuminating the dynamic process and characteristics of modeling of the experiment and discussing its educational meaning as a distributed cognitive system at each modeling unit. First, students, instruments, and the primitive form of calculation represented by the interaction between them turned out to be important factors in the distributed cognitive system that constitutes model of the experiment. Second, in the early stages, non-verbal activities were carried out in which students became familiar with instruments, and verbal quantitative signs were created when the activities were sufficiently carried out. The generated quantitative signs became a source of data and confidence that can be referenced in subsequent activities. Third, the specialization of instrumentalization occurred, and factors that were important in inquiry, such as variable control, appeared. The results of the study provide new implications for science education research and education, which have been centered on explanatory models, by unfolding the characteristics of model of the experiment that have not been noticed in science education through students' inquiry.