• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.116-121
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• 2001

Verification of tool collision is an important issue in die and mold machining. In this paper three functions of verification are schematically explained based on Z-Map model. The first function is getting a collision-free region when a tool assembly and a part surface model are given. The second function estimates the shortest length of cutter shank with that the tool cuts all of a region without collision. The last one is cutting simulation considering all parts of tool assembly as well as cutter blade. Those functions can be easily implemented by using several basic operators of Z-Map model which are explained also. Proposed approaches have enough accuracy to verify collision in reasonable computing time.

• Journal of Biosystems Engineering
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• 제23권6호
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• pp.549-560
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• 1998

The dynamic model of a tractor-trailer system developed in the first part of this paper was verified in this article by comparing the simulated acceleration responses of the system with actually measured ones. A commercially available tractor and a trailer were used for the verification test. Values of the model parameters were measured or theoretically derived if the measurement was practically impossible. The tractor-trailer system was operated with different forward speeds over three equally spaced half-sine bumps on the flat concrete surface. Results of the verification tests showed that autospectra of the measured and simulated accelerations of the tractor-trailer system agreed well up to the frequencies slightly feater than the fundamental frequencies of the ground excitations and at the frequencies of engine excitations. The mean of normalized errors of the simulated responses to the measured ones was estimated to be less than 10% for all the test runs. The peak responses in the autospectra also coincided well both in the frequency and magnitude.

• 한국시뮬레이션학회논문지
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• 제14권3호
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• pp.147-154
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• 2005

In conventional approaches such as a functinal approach or a parametric approach to online signature verification, which could not deal with the local shape of signature, much various important informations inherent in the local part of signature shape have been overlooked. In this paper, we try a structural approach in which a signature is represented as a structural form of handwriting primitives and the local parts along a signature handwriting can be selectively compared according to their discrimination power in the process of signature verification, As a result, the error rate is diminished in the case that the weights of subpattern units is applied into comparing process, which is the degree of discrimination power of local part. And also, the global variation and complexity of each signature extracted from the analysis of local shape is found useful in determining the decision threshold more precisely.

• 대한조선학회논문집
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• 제51권6호
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• pp.510-520
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• 2014

Unlike other mass production in small variety, shipbuilding process is a project-based method in single variety, which causes unpredictable volatility in the planning system. In shipyards, series of manufacturing processes from fabrication to erection is sequentially carried out. In order to predict unfavorable changes such as overload or low load of working volume, computerized simulation has been being gradually adopted. The data used in the simulation are processed from the database of the main scheduling and planning system. Thus the quality of those data is very crucial for the meaningful results. Unfortunately, research on the verification of data quality is very rare and hardly known to the authors. In this work, using the database of scheduling and product information system of a large domestic shipyard, the data required for the simulation are qualitatively analyzed and verified.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권10호
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• pp.4703-4723
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• 2016

The verification of data integrity is an urgent topic in remote data storage environments with the wide deployment of cloud data storage services. Many traditional verification algorithms focus on the block-oriented verification to resolve the dispute of dynamic data integrity between the data owners and the storage service providers. However, these algorithms scarcely pay attention to the data verification charge and the users' verification experience. The users more concern about the availability of accessed files rather than data blocks. Moreover, the data verification charge limits the number of checked data in each verification. Therefore, we propose a mixed verification protocol to verify the data integrity, which rapidly locates the corrupted files by the file-oriented verification, and then identifies the corrupted blocks in these files by the block-oriented verification. Theoretical analysis and simulation results demonstrate that the protocol reduces the cost of the metadata computation and transmission relative to the traditional block-oriented verification at the expense of little cost of additional file-oriented metadata computation and storage at the data owner. Both the opportunity of data extracted and the scope of suspicious data are optimized to improve the verification efficiency under the same verification cost.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1465-1469
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• 2003

In general satellite verification process, the AOCS (Attitude & Orbit Control Subsystem) should be verified through several kinds of verification test which can be divided into two major category like FBT (Fixed Bed Test) and polarity test. And each test performed in different levels such as ETB (Electrical Test Bed) and satellite level. The test method of FBT is to simulate satellite dynamics with sensors and actuators supported by necessary environmental models in ETB level. The VDS (Vehicle Dynamic Simulator) try to make the real situation as possible as the on-board processor will undergo after launch. The purpose of FBT test is to verify that attitude control logic function and hardware interface is designed as expected with closed loop simulation. The VDS is one of major equipments for performing FBT and consists of software and hardware parts. The VDS operates in VME environments with target board, several commercial boards and custom boards based on the VxWorks real time operating system. In order to make time synchronization between VDS and satellite on-board processor, high reliable semaphore was implemented to make synchronization with the interrupt signal from on-board processor. In this paper, the real-time operating environment used on VDS equipment is introduced, and the hardware and software configurations of VDS summarized in the systematic point of view. Also, we try to figure out the operational concept of VDS and AOCS verification test method with close-loop simulation.

• 한국환경과학회지
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• 제14권12호
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• pp.1155-1161
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• 2005

Anoxic-oxic process were analyzed numerically for the each unit and final TN effluent by Water Quality Management(WQM) model and the results were compared data from these sewage or wastewater treatment plants. No bugs and logic error were occurred during simulation work. All of the simulation results tried to two times were obtained and both results were almost same thus this model has good reappearance. A few of simulation results were deviated with measured data because lack of influent water qualities are reported however simulation results have wholly good relationship with measured data. Also each unit of simulation result was kept good relationship with that of measured data therefore this WQM model has good reliance. Finally, WQM model predicts final TN effluent within ${\pm}4.1\;mg/{\ell}$

• 전기학회논문지
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• 제64권2호
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• pp.331-337
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• 2015

The power flow analysis of electrified railway is required complicated calculation, because of variable load. Train runs trough rail supplied by electric power therefore, the load value in electrified railway system fluctuates along time. The power flow algorithm in electrified railway system is different from general power system, and the power flow simulation is peformed by the particular simulation software. Powerail is simulation software for analysis of traction power supply system developed by KRRI, in 2008. This consists of load forecasting module, including TPS and time scheduling, and power flow module. This software was verified by measured current under normal feeding condition, however, has not been verified by voltage on the condition of extended feeding. This paper presents the verification of PowerRail based on voltage drop under extended feeding condition. This is performed by comparing simulation result with field test. Field test and simulation is done in commercial railway line.

• 설비공학논문집
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• 제12권1호
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• pp.12-19
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• 2000

The multi type heat pump system may provide more energy savings and better environmental conditions than the single type heat pump system may do. In order to design a multi type heat pump system, it may be recommended to develop the system simulation program, which can predict the characteristics of the system such as unit capacities, power consumptions, and system COP's. In this study, the steady state simulation program of the multi type heat pump system was developed. The results from the simulation program were compared with those from the experimental tests which were performed in the environmental chamber, Cooling tests show 3.11% and 0.94% of error in capacity and COP, and heating tests show 3.30% and 1.90% of error in capacity and COP, respectively. Therefore, the steady state simulation program developed for this study can effectively be used for the design and the performance prediction of the multi type heat pump system.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.755-758
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• 1998

As the performance of microprocessor improves, the design complexity grows exponentially. Therefor, it is very important to make the bug-free model as early as possible in a design life-cycle. This paper describes the simulation-based functional verification methodology for the RTL level description model. It is performed by multi-stage verification methods using extensive hand-generated self-checking tests supplemented with random tests. This approach is opplied to the functional verification of the GPU processor of Raptor and various bugs are detected.