• Transactions of Materials Processing
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• v.22 no.4
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• pp.189-195
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• 2013

In this study, the weld strength of extru-rivet spot welding was investigated by simulation and experiment. In order to obtain hot plasticity flow bonding of the two plates by a single rivet, electrodes are used for heating of the two plates and the rivet by electric resistance. Because weld strength is influenced by the temperature in the weld zone, the diameter of the electrodes and the amount of current supplied to the electrodes are important variables. For the simulation, heat distribution and weld strength were calculated using DEFORM-3D. The weld strength in the weld zone was calculated for various values of the experimental parameters. The simulation results showed that the weld strength was the highest when the weld current was 37kA, the electrode diameter was 12mm, and the welding frequency was 90cycle. Aluminum 5052 was used for the experimental study. A total of three aluminum plates, two welding plates with 1mm thickness and one plate with 2mm thickness for the inserting rivet, were used for the experimental extru-rivet spot welding.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2006.04a
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• pp.258-262
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• 2006

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.5
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• pp.329-331
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• 2014

JavaScript is widely used to offer interactive web service and dynamic content. However, the number and size of JavaScript constituting the web page has been increasing steadily, and this circumstance leads to falling web performance. In this paper, we suggest a scheme for acceleration of JavaScript transmission considering software module reusability. We perform network simulation for the performance evaluation and analysis about the suggested scheme, and then confirm that the suggested scheme offers better performance in term of page loading time and the amount of traffic generated in the network than the transmission method using Gzip.

• Korean Journal of Veterinary Service
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• v.24 no.2
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• pp.117-126
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• 2001

To ensure the safety of domestic livestock products, the government made it obligatory to enforce the hazard analysis critical control point(HACCP) in all domestic slaughterhouses. Under the HACCP, most of the hazards generated in slaughterhouses are bio-hazards, especially pathogenic bacteria. In order to reduce to the pathogenic bacteria, critical control point (CCP) is established and controled in the process of slaughter. A study was carried out to measure the level of bacterial contamination of swine carcass in 6 slaughterhouses selected. As a result, the aerobic plate counts(cfu/$\textrm{cm}^2$) of all samples was $10^2$-10 in average, except slaughterhouse C. The level of the aerobic plate counts on the surface of lower loin in slaughterhouse C was $10^4$ and it was considered that slaughterhouse C should set the process of manual transport of carcass as the CCP. Escherichia coli level was the highest in middle line cut surface. Especially, E coli level of slaughterhouses C and D were about 6.5- and 3.0-fold higher than that of other 4 slaughterhouses. Thus, it was considered that the slaughterhouses C and D should set the process of the entrails treatment as the CCP. The air contamination was measured at two point in a slaughterhouse. The air contamination level was 4-13 times higher than that of the standard Japanese slaughterhouses.

• Journal of Science and Technology Studies
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• v.7 no.2
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• pp.23-46
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• 2007

이 글은 황우석 사태에 대한 기존의 연구들이 황우석 사태에 대한 정의도 뚜렷이 내리지 않고 그 용어를 쓰고 있으며, 아울러 황우석 사태를 대체로 한국적 후진성을 반영하는 현상으로 묘사하는 것은 나름대로 수긍할만한 측면이 없는 것은 아니지만, 황우석 사태를 올바로 이해하는 데 있어 걸림돌이 될 수 있다는 문제의식에서 출발하였다. 황우석 사태는 여성들의 난자들에 대한 비윤리적 사용 의혹에서 비롯되어 논문조작 의혹이 제기되고 그 의혹들이 맞는 것으로 밝혀지는 일련의 과학적 부정행위 규명과, 그 과정에서 논문조작이 밝혀졌음에도 불구하고 대중들이 보여준 황우석에 대한 비이성적 지지 현상 모두를 의미하는 것으로 이해되어야 한다. 황우석 사태를 이렇게 정의할 때, 우리는 황우석 사태가 세계적으로 볼 때 보편적 성격과 특수적 성격 모두를 지니고 있다고 평가할 수 있다. 한편으로 논문조작에 초점을 두고 황우석 사태를 보면 황우석 사태는 한국만의 현상이 아니라 세계사적 보편성을 지니고 있다고 할 수 있는데, 그 구조적 원인으로는 과학자간 경쟁의 격화와 업적주의의 강화를 들 수 있다. 다른 한편으로 논문조작이 밝혀졌음에도 불구하고 황우석에 대한 대중들의 열광적인 지지가 지속되었던 점에 초점을 두고 황우석 사태를 보면 황우석 사태는 다른 나라들에서는 그 유례를 찾을 수 없는 한국적 현상이라고 할 수 있는데, 그 현상의 근원에는 대체로 한국인들이 지니고 있는 한의 정서가 자리 잡고 있다고 할 수 있다.

• Korean Journal of Bronchoesophagology
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• v.18 no.1
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• pp.5-8
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• 2012

Cryosurgery is a safe method for palliation of endobronchial malignancies causing airway obstruction. Due to its simplicity and effectiveness for controlling bleeding, endobronchial cryosurgery is considered to be a good method that is clinically applicable to a malignant endobronchial tumor. In cases with stenosis caused by an endoluminal tumor, cryo-recanalization with a cryoprobe was immediately effective in most of the patients. A novel technique described by Hetzel in 2004 to achieve rapid recanalization of central airway obstruction with endobronchial cryoprobe. Cryorecanalization technique is feasible and offers many advantages in the interventional therapy of malignant intraluminal tumors of the respiratory tract.

• Journal of IKEEE
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• v.21 no.3
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• pp.272-275
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• 2017

Recently, semiconductor integration density enormously increases and its interconnection width is significantly narrowed, which leads to EMI (electromagnetic interference) problems on chip level. Chip manufacturer exploits TEM cell (transverse electromagnetic cell) to measure EMI on chip level, which requires PCB (printed circuit board) for measurement purpose. However, it is often neglected to consider that PCB patterns and other factors can affect on EMI measurement. In this paper, several test patterns are designed for different PCB design variables, and effects of PCB patterns on EMI measurement in TEM cell are analyzed. Based on these analyses, PCB design guidelines are also proposed to minimize the effects on EMI measurements.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.1011-1015
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• 2017

In this study, numerical and experimental studies on the nozzle flow in a sub-scale cold flow test were conducted to simulate high altitude condition. In the theoretical calculation, the temperature of the nozzle outlet is calculated to be lower than the liquefaction point, and the fluid exists at the phase change point. Also, numerical analysis result is higher than theory calculation but lower than liquefaction temperature. As a result of cold flow test, it was confirmed that the temperature was much higher than theory and analysis. This is because it assumed that it is adiabatic in the theoretical calculation, but the experiment in the actual environment is not the adiabatic but the heat exchange with the outside exists.

• Journal of Convergence for Information Technology
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• v.7 no.4
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• pp.69-74
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• 2017

ICT(Information Communication Technology) is a key word in our society on today. Various support programs by the government have given many quantitative and qualitative changes to the software industries. Software is instructions(Computer Program) and data structure. Software can be divided into Application program and System program. Application programs have been developed to perform special functions or provide entertainment functions. Because of this rapid growth of software industries, one of the problems is issue on copyright of program. In this paper, we described an analysis method for program similarity based on source code in program.

• Information and Communications Magazine
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• v.28 no.9
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• pp.3-9
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• 2011

본고에서는 급속히 성장하고 있는 M2M 서비스의 융합과 발전을 위해 어떤 걸림돌이 있으며, 무엇을 준비해야 하는지에 대해 알아보고자 한다. 지난 1T839 정책에서 3대 인프라의 하나로 정의된 USN이 본격 확산에 미흡했던 사항에는 어떤 것들이 있었으며 당시 기술적인 환경과 서비스 사례를 통해 2% 부족했던 것들은 되짚어 보고, USN이 현재 시점에 가지는 의미를 찾아보고자한다. USN 서비스가 활성화 되던 시점에 M2M의 기반기술이라고 할 수 있는 (W)CDMA 등 광역 무선망 기술과의 접목이 어려웠던 부분과 USN의 다양한 근거리 무선 네트워크 기술들이 USN 서비스를 완벽히 구현하고 확산까지 갈 수 없었던 미흡했던 이유를 알아보고자 한다. 또한 M2M의 시작배경에는 어떠한 의미가 있으며, 현재에서 바라본 M2M은 시작과 비교해서 달라진 점이 무엇이며 현재에 요구되는 M2M은 무엇인지에 대해 논의해보고자 한다. 이와 함께 M2M의 다양한 정의와 현재의 M2M을 비교해보고 M2M이 급속히 증가하고 있는 이유들을 찾아본다. M2M 서비스를 크게 나누면 텔레매틱스와 텔레매트리로 나눌 수 있으며 최근에는 차량 관련된 분야에 M2M 서비스가 급속히 증가되고 있는데 해외의 eCall 서비스와 국내의 DTG 연계 M2M 서비스, 국가위험물관리 등 국내외 차량관련 M2M 서비스 사례를 분석해 보고, RFID/USN+LBS+M2M의 융복합 서비스 진화에 대해 알아보고자 한다. 끝으로 M2M 시대의 시대적 요구사항을 반영하여 M2M의 활성화를 위해서 필요한 공공과 민간의 역할을 짚어보고, 우리가 준비해야할 것에 대해 제언하고자 한다.