• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.2
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• pp.103-109
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• 2017

Metal 3D printing, which is an additive metal manufacturing (AMM) process, enables the development of full-density metallic tools and parts using metal powders that are precisely delivered and controlled for deposition with no powder bed. However, some unknown geometric defects and irregular geometric features on an STL model can possibly result in incorrect metal part fabrication after the build. This study first proposes a methodical approach for verifying the build part, including the missing facet problems in an STL model, by defining some irregular features that possibly exist on the part. Second, 2D tool paths on each build layer were investigated for detecting any singular region inside the layer. The method was implemented for building two sample STL models using a direct energy deposition process, and finally, it was visually simulated for diagnosis.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.11
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• pp.2409-2414
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• 2002

The surfaces of prototypes become rough due to the stair-stepping which is the inevitable phenomenon in the Rapid Prototypes are not used only for the verification of feature. The grinding, coating, or the composition of them is a main operation in post-processing in which lots of costs and long build time are needed. The solution is proposed to increase the efficiency of rapid prototyping by minimizing or removing the composition of them is a main operation in post-processing in which lots of costs and long build time are needed. the solution is proposed to increase the efficiency of rapid prototyping by minimizing or removing the regions for post-processing. the factors to cause the surface roughness and their effects are analyzed through the experiments. Software modules are developed to predict the surface roughness of each face in the prototyping with the result. An experimental compensation method is developed to apply the modules to various RP equipments, materials and build styles. The build direction is searched with use of genetic algorithm to maximize the total areas of the surface of which roughness is better than the user-defined value.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.2
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• pp.103-114
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• 2013

The Korea Atomic Energy Research Institute has developed a performance assessment model implementing the A-KRS concept, which was constructed with the GoldSim. In the A-KRS concept, spent nuclear fuel produced from pressurized-water-reactor operations would be pyroprocessed to reduce waste volume and radioactivity. The wastes to be disposed of in a geologic repository are comprised of metal and ceramic waste forms. In this study, results of simulations conducted to establish credibility and build confidence for the A-KRS model are presented. Specifically, release rates and breakthrough times simulated using the A-KRS model were compared to corresponding results from the U.S. NRC SOAR model. In addition, the A-KRS model results were compared to published release rates from the SKB repository performance assessment. This comparison of the A-KRS model results to other independent performance assessments is expected to form part of a suite of model verification and validation activities to provide confidence that the A-KRS model has been implemented appropriately.

• The KIPS Transactions:PartA
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• v.12A no.6 s.96
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• pp.523-530
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• 2005

When a PCI 2.2 bus master requests data using Memory Read command, a target device may hold PCI bus without data to be transferred for long time because a target device needs time to prepare data infernally. Because the usage efficiency of the PCI bus and the data transfer efficiency are decreased due to this situation, the PCI specification recommends to use the Delayed Transaction mechanism to improve the system performance. But the mechanism cann't fully improve performance because a target device doesn't know the exact size of prefetched data. In the previous work, we propose a new method called Prefetch Request when a bus master intends to read data from the target device. In this paper, we design PCI 2.2 controller and local device that support the proposed method. The designed PCI 2.2 controller has simple local interface and it is used to convert the PCI protocol into the local protocol. So the typical users, who don't know the PCI protocol, can easily design the PCI target device using the proposed PCI controller. We propose the basic behavioral verification, hardware design verification, and random test verification to verify the designed hardware. We also build the test bench and define assembler instructions. And we propose random testing environment, which consist of reference model, random generator ,and compare engine, to efficiently verify corner case. This verification environment is excellent to find error which is not detected by general test vector. Also, the simulation under the proposed test environment shows that the proposed method has the higher data transfer efficiency than the Delayed Transaction about $9\%$.

• Korean Journal of Computational Design and Engineering
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• v.12 no.1
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• pp.39-49
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• 2007

Recently three-dimensional (3-D) die design and production process has been widely introduced into the tooling shops of automotive manufacturers to reduce time-to-production of brand-new automobiles. 3-D solid models created in CAD systems are used not only for various simulations for design verification, but also for NC tool path generation to machine dies and their Styrofoam patterns. However, a lot of time and cost will be required to build solid models for dies if designers use only the generalized modeling capabilities of commercial 3-D CAD systems. To solve this problem, it is necessary to customize 3-D CAD system for the specific die design and manufacturing process. This paper describes a dedicated 3-D CAD system based on Unigraphics for die design for automotive body panels. The system provides not only 3-D design capabilities, but also standard part libraries, to enhance design productivity. The design process modeling technology has been introduced to facilitate redesign of the die for the modified panel. By introducing this system, dies can be designed more rapidly in the 3-D space, and their solid data can be directly transferred to CAM tools for NC tool path generation and simulation tools for virtual manufacturing.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1424-1428
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• 2005

This paper describes a dedicated three-dimensional CAD system for design of drawing dies for automotive body panels. Since solid die models are useful not only for simulations for design verification, but also for NC tool path generation to machine dies and their Styrofoam patterns, 3-D CAD systems have been introduced in the tooling shop of automotive manufacturers. However, the work to build solid models requires a lot of time and effort if the designer uses only the general modeling capabilities of commercial 3-D CAD systems. To solve this problem, we customized a 3-D CAD system for the drawing die design. The system provides not only 3-D design capabilities, but also standard part libraries to enhance design productivity. By introducing this system, the drawing dies can be designed more rapidly in the 3-D space, and their solid data can be directly transferred to CAM tools for NC tool path generation and simulation tools for virtual manufacturing

• Korean Journal of Artificial Intelligence
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• v.5 no.2
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• pp.15-25
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• 2017

Recently, technologies are being developed to recognize and authenticate users using bioinformatics to solve information security issues. Biometric information includes face, fingerprint, iris, voice, and vein. Among them, face recognition technology occupies a large part. Face recognition technology is applied in various fields. For example, it can be used for identity verification, such as a personal identification card, passport, credit card, security system, and personnel data. In addition, it can be used for security, including crime suspect search, unsafe zone monitoring, vehicle tracking crime.In this thesis, we conducted a study to recognize faces by detecting the areas of the face through a computer webcam. The purpose of this study was to contribute to the improvement in the accuracy of Recognition of Face Based on CNN Algorithms. For this purpose, We used data files provided by github to build a face recognition model. We also created data using CNN algorithms, which are widely used for image recognition. Various photos were learned by CNN algorithm. The study found that the accuracy of face recognition based on CNN algorithms was 77%. Based on the results of the study, We carried out recognition of the face according to the distance. Research findings may be useful if face recognition is required in a variety of situations. Research based on this study is also expected to improve the accuracy of face recognition.

• Journal of the Korea Institute of Military Science and Technology
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• v.3 no.2
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• pp.166-178
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• 2000

As the 21st century signifies an information-oriented society, the computer integration takes place in all walks of human presence. Needs for computer and network-integrated automation present new challenges in military as well as commercial facility systems engineering. Since the first intelligent building appeared in USA in 1984, it gradually became an essential capability for the building industry requirement these days. Intelligent Building System(IBS) is evolving to be very complex because there are many subsystems such as telecommunication(TC), office automation(OA), building automation(BA), security, construction environments, etc. During the planing phase of IBS development, therefore, a disciplined systems engineering must be performed to analyze stake- holder's requirements to build an optimized system while minimizing trial-and-error expenses and risks. This paper presents a conceptual design of BAS applying systems engineering methods. The contribution of this study includes the development of IBS subsystem specification for building automation subsystem, which is a part of IBS, using the methodology of requirement analysis, functional analysis, synthesis, and verification. A computer-aided systems engineering s/w, RDD-100, was used to improve the system design efficiency and to promote the product design knowledge management for reuse in later design programs.

• Journal of Convergence for Information Technology
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• v.10 no.9
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• pp.147-153
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• 2020

As demand for drone test flight is rapidly increasing, it is difficult for Goheung Aviation Center alone to meet the test flight demand. Newly developed drones or modified existing aircraft carry potential flight risks due to unpredictable flight performance or poor pilot skill when performing test flights outside the test site. Therefore, it is necessary to ensure sufficient test flight space for the safety verification of manned and unmanned aircraft. Therefore, this study analyzed the status of domestic flight test site and chapter 5 of ICAO DOC 9184-AN / 902 Part 1 (Airport Planning Manual). And to build a comprehensive flight test infrastructure, the methodology for preliminary evaluation of candidate sites for flight test sites and a method for evaluating infrastructure test sites was presented.

• KIEAE Journal
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• v.17 no.1
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• pp.5-13
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• 2017

Purpose: This study, by comprehensively the characteristics of new Hanok application techniques with the proposed site application technology in the course of the design changes that have been accumulated through Hanok technology development the second stage business, by analyzing the range of reflection, new Considering the direction reflects the efficiency of the new Hanok application techniques. Method: new Hanok application technology, it was been established through research and development of large 1 new Hanok technology it has been proposed through the "site-specific application techniques" and 2 builders and designers "space-time proposed technique" Analysis of the case, at the center of the design changes, the land the body of laws and regulations, the requirements of the public buildings, compared to the construction method and the like for the reduction of construction costs, new Hanok applied technology in the process of change by it There was analyzed whether acceleration on the range and step which is reflected in the design Result: The result of new Hanok applied technology was built through the demonstration build business case, process another major technology, foundation, woodwork, walls, roof, has been reflected in the ceiling construction, the inclusion of items in the proposed technique of construction , it was applied to the main steps in general, except for other construction work landscaping. Application techniques and construction proposal technology research team has presented, show the difference between the scope and method. With significance effort to improve the unreasonable traditional methods of these core processes that can be reflected in the field repeated the construction proposed technique as a result of the utility that can be applied for substantial construction.