• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.205-209
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• 2007

During after the Industrial Revolution until now, as many of working machinery and tool had been invented, human could save man power and time. However, because such instruments generate a loud noise according to their use-purposes and dimensions, they are affecting a physical, mental bad influences to those workers. Therefore, while a reduction measure against the instrument-noise that generates at workshop is sincerely necessitated, due to lack of the research and data concerned with that, a lot of difficulties are on suffering. Standing on such point of view, this Study has measured analyzed the characteristics of diverse instrument-noises generate at workplace, and would intends to present a fundamental material for establishment more comfortable working environment by prediction on the noise in loud noise workshop, based on the above.

• Advances in Computational Design
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• v.1 no.4
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• pp.357-370
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• 2016

This paper aims to examine the dynamic response of a newly designed ultrasonic motor under half-sine shock impulses. Impact shock was applied to the motor along x, y or z axis respectively with different pulse widths to check the sensitivity of the motor to the shocks in different directions. Finite Element Analysis (FEA) with the ANSYS software was conducted to obtain the relative displacement of a key point of the motor. Numerical results show that the maximum relative displacement is of micro meter level and the maximum stress is five orders smaller than the Young's modulus of the piezo material, which proves the robustness of the motor.

• Journal of the Korean Professional Engineers Association
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• v.42 no.5
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• pp.29-31
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• 2009

A general practice in software ordering behavior in public sector has been an enormous obstacle standing in development path of Korea's software industry. Standard on software development cost estimation is supposedly based on Function Point, but in general, it is on headcounting (a number of people involved in a project). Moreover, it is difficult to change a contract in an on-going project, since statement of work is not precisely and carefully described. But it has a simple solution. Design and Implementation should be a separate project, as in construction industry, and both power and responsibility for design should be given to an expert with a national-level qualification. Here, there is a simple way for Korea to reborn as one of the strongest software country.

• Journal of the Korean Institute of Navigation
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• v.22 no.1
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• pp.91-106
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• 1998

Traditionally, in the education for the trainees of marine officier, the emphasis is laid on the practical training on board to prepare them for the future position on board and to fit them for the shipboard life. Though the education has been carried out in various ways according to each country's social tradition, culture and educational system, in these days it is done normally by the combined way of school education and training on board to get the competence for the marine officer. Thus the shipboard training course is compulsively required to the candidates for certification as merchant marine officers by the IMO STCW convention 1978 and also it is believed that the education for the dacet officers is to be completed through the shipboard training. In spite of the various earlier studies to improve the training education system, there are few studies for the matters and problems form the standing point of cadet.

• Journal of Korean Society on Water Environment
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• v.25 no.5
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• pp.641-650
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• 2009

The IPCC's standing on the anthropogenic warming is discussed in this article. The differences between the climate alarmist and skeptics have been addressed in terms of scientific and policy stand point of view. The political and economical significances of climate change have been discussed, too. Although atmospheric temperature and rainfall precipitation are two most important factors in the climate change, most of the recent attentions have drawn on mainly temperature and $CO_2$ issue. In spite of argues on the uncertainty in anthropogenic warming related to $CO_2$, the inevitable climate change should correspondingly change the humanity in near feature.

• The Journal of the Korean dental association
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• v.48 no.2
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• pp.91-94
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• 2010

Regarding the improvement of the dental specialist program, two related issues were reviewed extensively: (a) bill amending portions of the Medical Service Act as proposed by national assemblywomen Choi Yeong-hui (Democratic Party) and Chung Mi-gyeong (Grand National Party), and; (b) Plans to supplement the submitted bill. Although the existing bill's prospects in the assembly are unclear at this point, both the existing and planned supplementary bills zero in on two points: (a) specialists must focus on providing care only in their respective expertise, and; (b) a distinction between the roles played by the primary, secondary, and tertiary medical institutions must be made to help establish clearly the country's overall health care system. In addition, proposals were made for medical license renewal among specialists so that professionals can offer better health care to customers.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.523-528
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• 2000

In this paper, the new type biped walking robot which is composed of the minimum number or links just for walking and its appropriate gaits are proposed. The proposed new gaits for this robot are four-crossing, crawling, standing and turning gait. In designing the biped robot we propose the Performance Index which means the needed torque per a moving distance and generate foot trajectories by $3^{rd}$ order spline Interpolation. Among those, numerically we find the optimal conditions which minimize the Performance Index. Dynamically stable walking of the biped robot is realized by satisfying the stability condition of ZMP(zero moment point), which is related to maintaining the ZMP within the region of the supporting foot during the s1n91e leg support phase. We determine the region of mass center from the stability condition of ZMP and plan references which track the mass conte. trajectory of constant velocity. Finally we implement the gaits statically tracking the planned trajectories using PD control method.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.1
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• pp.162-168
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• 2003

The purpose of this research is to develop the multimedia contents for the subject . is the subject to understand and analyze the characteristics of the textile materials and to be putting the key point to utilize the textile materials as the fashion materials. 1 developed the contents using multimedia system standing on the basis of Internet. The developed contents were organized to induce the interest. The sounds, pictures. computer graphics, animations, text, AOD and AOD etc. were utilized in these contents. These contents were consisted of preview, restudy, and the feedback through question. These contents can be executed directly in Web browser through Internet. Address is http://web.cnu.ac.kr/-fabric. Ⅰ applied this multimedia contents to actual class. It was utilized much more than textbook and it was turned out to be efficient in the experiment class. It was inspected that the most of students were satisfied with the utilizing these multimedia contents.

• The Korean Journal of Ceramics
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• v.3 no.1
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• pp.29-33
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• 1997

Four diamond films were deposited by the microwave plasma assisted chemical vapor deposition method varying CH4 concentration from 2.5 to 10% in the feeding gases. Thermal conductivity was measured on these free standing films by the steady state method from 80 K to 400K. They showed higher thermal conductivity as the film deposited with lower methane concentration. One exception, 7.79% methane concentration deposited film, was observed to be the highest thermal conductivity. Phonon scattering processes were considered to analyze the thermal conductivity with the full Callaway model. The grain size and the concentration of the extended and the point defects were used as the fitting parameters. Microstructure of diamond films was investigated with the scanning electron microscopy and Raman spectroscopy.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.3A
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• pp.356-359
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• 2006

A monolithic SiGe HBT variable gain driver amplifier(VGDA) with high dB-linear gain control and high linearity has been developed as a driver amplifier with ground-shielded microstrip lines for 5-GHz transmitters. The VGDA consists of three blocks such as the cascode gain-control stage, fixed-gain output stage, and voltage control block. The circuit elements were optimized by using the Agilent Technologies' ADSs. The VGDA was implemented in STMicroelectronics' 0.35${\mu}m$ Si-BiCMOS process. The VGDA exhibits a dynamic gain control range of 34 dB with the control voltage range from 0 to 2.3 V in 5.15-5.35 GHz band. At 5.15 GHz, maximum gain and attenuation are 10.5 dB and -23.6 dB, respectively. The amplifier also produces a 1-dB gain-compression output power of -3 dBm and output third-order intercept point of 7.5 dBm. Input/output voltage standing wave ratios of the VGDA keep low and constant despite change in the gain-control voltage.