• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.3
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• pp.729-737
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• 1994

A three-dimensional finite element model of a 20-pin plastic dual-in-line package(PDIP) plugged into a PCE has been developed by using the finite element code ANSYS. The model has been used for thermal characterization of the package during its normal operation under natural convection cooling. Temperature distributions in the package and PCB are obtained from numerical analysis and compared with experimentally measured data. Various cases are assumed and analyzed to study the effects of package and PCB materials on thermal characteristics of PDIP with and without aluminum heatspreader. Thermal dissipation capability of PDIP is greatly increased due to copper die pad/lead frame and heatspreader. However, thermally induced stresses in the package and fatigue life of chip are improved for PDIP with Alloy 42 die pad/lead frame and no heatspreader. It is also found that the role of PCB on thermal characteristics of PDIP is very imporatant.

• JSTS:Journal of Semiconductor Technology and Science
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• v.7 no.4
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• pp.229-234
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• 2007

In this paper, we present an efficient instruction set architecture using vector register file hardware to accelerate operation of general matrix-vector operations in DSP microprocessor. The technique enables in-situ row-access as well as column access to the register files. It can reduce the number of memory access significantly. The technique is especially useful for block-based video signal processing kernels such as FFT/IFFT, DCT/IDCT, and two-dimensional filtering. We have applied the new instruction set architecture to in-loop deblocking filter processing in H.264 decoder. Performance comparisons show that the required load/store operations for the in-loop deblocking filter can be reduced about 42%. The architecture would improve the processing speed, and code density in DSP microprocessor especially for video signal processing substantially.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.550-555
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• 2011

The objective of this study is to investigate flow characteristics of a underwater vehicle by installing pins, using CFD method with a commercial code FLUENT version 6.3.26. To verify the reliability of the computation, the drag is compared the CFD with the experimental test. The drag is increased about 15% by installing 4 pins. At the stern of the body, the turbulent flow is generated by installing pins. Also, the results showed that the drag increase in the stern of the body, not in the pins.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.6
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• pp.624-629
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• 2014

The purpose of this study is to carry out the task of engine hesitation which occurred intermittently in driving due to the defective CKPS of LPI vehicles. As the result of the wrong data from the equipment of D-logger, the signal error of CKPS caused the engine hesitation. We performed a study in the followings to analyze and investigate the cause effectively. First, we have investigated the control wiring harness and connector pin contact defect inspection. Second, we have inspected the defection of CKPS separately. From this study, it was found that the engine hesitation were caused by the bad durability and we have showed how to diagnosis the fault of the engine hesitation intermittently while driving. Therefore, it is determined that we have to improve the durability of the CKPS through a strict quality control and to increase the reliability.

• Proceedings of the Korean Society of Computer Information Conference
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• 2014.07a
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• pp.371-374
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• 2014

현재 국내에서 사용되고 있는 신분 인증 시스템은 주민등록번호와 같은 개인 정보를 기반으로 인증을 수행하여, 프라이버시 침해 위협이 존재한다. 그 해결 방안으로 가상 ID를 이용하는 I-PIN과 e-ID 카드가 제안되었지만, 문제점은 ID와 패스워드만 알고 있다면 누구나 도용이 가능하고 오프라인에서 사용하는 플라스틱 카드의 경우 위 변조가 가능하다는 한계를 갖는다. 본 논문에서는 주민등록번호를 대체할 식별 데이터인 QR-ID를 생성하고, 이에 기반을 둔 QR-ID 카드를 제안한다. QR 코드는 인식기에 대한 제약이 적고 일부 데이터 조작만으로 새로운 QR 코드 생성이 가능하여 노출 시 새로운 ID로 갱신할 수 있으며, QR-ID는 소유자의 바이오메트릭 데이터로 암호화되어 타인이 복호화 할 수 없다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.7
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• pp.1393-1400
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• 2017

As the number of smartphone users increases, vulnerability to privacy protection is increasing. This is because personal information is stored on various servers connected to the Internet and the user is authenticated using the same ID and password. Authentication methods such as OTP, FIDO, and PIN codes have been introduced to solve traditional authentication methods, but their use is limited for authentication that requires sharing with other users. In this paper, we propose the authentication method that is needed for the management of shared information such as hospitals and corporations. The proposed algorithm is an algorithm that can authenticate users in the same place in real time using smart phone IMEI, QR code, BLE, push message. We propose an authentication algorithm that can perform user authentication through mutual cooperation using a smart phone and can cancel realtime authentication. And we designed and implemented a mutual authentication system using proposed algorithm.

• Journal of the Korea Computer Industry Society
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• v.4 no.4
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• pp.547-552
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• 2003

In this thesis, interference phenomena of bluetooth networks requiring Security were minimized; strengthened security of piconet by assigning an identical PIN code to bluetooth devices, which was establishing a specific piconet during authentication stage. To establish a bluetooth piconet system. an unique ID was assigned to each bluetooth device, communication algorithms having different data formats between devices was designed, and an embedded hardware module using ARM processor and uCOS-II RTOS was implemented. About 30% of CPU efficiency in the module was increased by modifying functions including block parameters to work as nonblocking; by the increased efficiency of total piconet, the module could be used as an access point. The module could transmit maximum 10 frames of image and also audio signal by switching the packet effectively according to channel condition. By above-mentioned process, video, audio, and data could be well transmitted by the bluetooth managing program and the possibility of a commercial remote control system using bluetooth technology was suggested.

• Journal of the Korea Fashion and Costume Design Association
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• v.10 no.1
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• pp.99-116
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• 2008

This study reviewed pertinent literature and examined relics of manggon(a headband worn to hold a man's topknot hair in place), donggot(a topknot pin), and chigwan(a topknot cover). Before the modernized short hair style, wearing a gat was an important custom. Therefore, manggon, which was used to hold a man's hair in place under the gat, was considered an essential part of the man's official dress code. Donggot is a pin that held the topknot hair in place. It was a must have for a married man, like the binyeo, a lod-like hairpin, for a married woman. Unlike gwanja, it had nothing to do with official rank, but materials were of a variety of materials, including jade and gold. The structure of the donggot was studied in three parts-head, neck and body. Major forms for the head include the mushroom, bean and ball. Bullet and half-cut bullet forms were also found. Forms for the neck include straight-neck and curved-neck. A neck with a belt around a double chin was also found. Forms for the body include the tetrahedron, octahedron and cylinder. The most popular form for silver and white bronze donggot heads was the mushroom, followed by bean and pile forms. Chigwan is also called chipogwan, chichoal, choalgyesogwan, noingwan and sangtugwan. In poetry it was called chichoal, and it used to be called taegogwan in the past as well. Chigwan was so small that it managed to hold a topknot. According to confucian custom in the Joseon period, by wearing chigwan, men didn't display their bare topknot even when they didn't dress up. When they went out, they wore another official hat over the chigwan.

• Journal of Convergence Society for SMB
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• v.1 no.1
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• pp.29-37
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• 2011

As the area of informatization has been expanding followed by the development of information communication technology, cloud computing which can use infra sources like server, storage, and network in IT area as an efficient service whenever and wherever skyrockets. But users who use cloud computing technology may have some problems like exposure personal data, surveillance on person, and process on commercial purpose on their personal data. This paper proposes a security technique which protect user's privacy by creating imaginary user information not to be used by other people. The proposed technique virtualizes user's information as an anonymity value not to let other people know user's identity by combining PIN code with it and guarantees user's anonymity. Also it can manage and certificate personal information that is important in cloud computing, so that it can solve security problem of cloud computing which centers all informations. Therefore this paper can assist upgrading of the level of information of poor SMBs through safe use of cloud computing.

• Nuclear Engineering and Technology
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• v.36 no.6
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• pp.528-539
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• 2004

It is essential in commercial reactors that the safety limits imposed on the fuel pellets and fuel clad barriers, such as the linear power density (LPD) and the departure from nucleate boiling ratio (DNBR), are not violated during reactor operations. In order to accurately monitor the safety limits of current reactor states, a detailed three-dimensional (3D) core power distribution should be estimated from the in-core detector signals. In this paper, we propose a calculation methodology for detailed 3D core power distribution, using in-core detector signals and core monitoring constants such as the 3D Coupling Coefficients (3DCC), node power fraction, and pin-to-node factors. Also, the calculation method for several core safety parameters is introduced. The core monitoring constants for the real core state are promptly provided by the core design code and on-line MASTER (Multi-purpose Analyzer for Static and Transient Effects of Reactors), coupled with the core monitoring program. through the plant computer, core state variables, which include reactor thermal power, control rod bank position, boron concentration, inlet moderator temperature, and flow rate, are supplied as input data for MASTER. MASTER performs the core calculation based on the neutron balance equation and generates several core monitoring constants corresponding to the real core state in addition to the expected core power distribution. The accuracy of the developed method is verified through a comparison with the current CECOR method. Because in all the verification calculation cases the proposed method shows a more conservative value than the best estimated value and a less conservative one than the current CECOR and COLSS methods, it is also confirmed that this method secures a greater operating margin through the simulation of the YGN-3 Cycle-1 core from the viewpoint of the power peaking factor for the LPD and the pseudo hot pin axial power distribution for the DNBR calculation.