• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 추계학술대회 논문집
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• pp.166-169
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• 2001

22,000 Ton hydraulic press was developed using wire winding method. The hydraulic press consists of three piece of frame type. The outer layers of yoke-column frame and main cylinder linear were wound with piano wire(1mm${\times}$4mm) under controlled tension and the total length of wound wire was about 450Km. The developed hydraulic press is used for the forming of heat plate with ultra-large size. To obtain large force with relative small apparatus, high pressure of $1,500 Kgf/cm^2$ was supplied to main cylinder through pressure amplification by booster pump. Therefore sealing technique of main cylinder is so crucial that the seals were made of mitre ring type with super-elastic metal. The press total weight is about 150 tons, which is quite light and compact relative to that of conventional hydraulic press.

• 한국안광학회지
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• 제12권4호
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• pp.15-18
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• 2007

티타늄과 그 합금은 경량성, 우수한 기계적 성질 및 내식성 때문에 주요한 안경테 소재로 사용되고 있다. 본 연구에서는 안경테 소재로 사용되고 있는 순 티타늄(P-Ti)과 ${\beta}$-티타늄(${\beta}$-Ti)에 대하여 전기저항땜질 장치를 이용하여 접합조건의 변화에 따른 접합부의 특성 변화에 대하여 조사하였다. P-Ti 및 ${\beta}$-Ti 모두 접합부 근처에서 경도값의 감소가 나타났으며, 이는 전기저항열에 따른 결정립의 조대화 때문이다. 결정립 조대화에 의한 경도의 저하량 및 저하된 부분의 크기는 ${\beta}$-Ti 보다 P-Ti에서 크게 나타났다.

• 한국정밀공학회지
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• 제23권5호
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• pp.51-58
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• 2006

The necessities for heightening fuel efficiency as well as lightweight design, lead to an increase of the use of aluminum alloys in the automobile industry. Extruded aluminum profile channels are used widely for the design of frame parts as lightweight assemblies, especially if a high stiffness is needed. While many applications can be realized with forming of hollow square-sectioned extruded profiles such as a stretch bending and a hydro-forming, some applications demand the use of a press bending which can be hardly found in the previous study. In this study, by introducing the use of a press bending into car sub-frames, the demands for higher accuracy as well as higher flexible method than the conventional methods will be satisfied. With respect to the design of sub-frames, the process planning was performed from the shape of a sub-frame product. The designed processes were analyzed by the commercial FEM code, DEFORM-3D. Forming dies for the each process were designed and prototypes of sub-frames were manufactured by the verified farming process. In addition, some of the important features of design parameters in the press bending were reviewed.

• Journal of Astronomy and Space Sciences
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• 제33권4호
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• pp.247-256
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• 2016

An analysis of light curves and spectra of observed gamma-ray bursts in gamma-ray ranges is frequently demanded because the prompt emission contains immediate details regarding the central engine of gamma-ray bursts (GRBs). We have revisited the relationship between the collimation-corrected peak luminosity and the spectral lag, investigating the lag-luminosity relationships in great detail by focusing on spectral lags resulting from all possible combinations of channels. Firstly, we compiled the opening angle data and demonstrated that the distribution of opening angles of 205 long GRBs is represented by a double Gaussian function having maxima at ~ 0.1 and ~ 0.3 radians. We confirmed that the peak luminosity and the spectral lag are anti-correlated, both in the observer frame and in the source frame. We found that, in agreement with our previous conclusion, the correlation coefficient improves significantly in the source frame. It should be noted that spectral lags involving channel 2 (25-50 keV) yield high correlation coefficients, where Swift/Burst Alert Telescope (BAT) has four energy channels (channel 1: 15-25 keV, channel 2: 25-50 keV, channel 3: 50-100 keV, channel 4: 100-200 keV). We also found that peak luminosity is positively correlated with peak energy.

• 천문학회보
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• 제46권2호
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• pp.36.1-37
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• 2021

Six images of IRC+10216 taken by the Hubble Space Telescope at three epochs in 2001, 2011, and 2016 are compared in the rest frame of the central carbon star. An accurate astrometry has been achieved with the help of Gaia Data Release 2. The positions of the carbon star in the individual epochs are determined using its known proper motion, defining the rest frame of the star. In 2016, a local brightness peak with compact and red nature is detected at the stellar position. A comparison of the color maps between 2016 and 2011 epochs reveals that the reddest spot moved along with the star, suggesting a possibility of its being the dusty material surrounding the carbon star. Relatively red, ambient region is distributed in an Ω shape and well corresponds to the dusty disk previously suggested based on near-infrared polarization observations. In a larger scale, differential proper motion of multiple ring-like pattern in the rest frame of the star is used to derive the average expansion velocity of transverse wind components, resulting in ~12.5 km s-1 (d/123 pc), where d is the distance to IRC+10216. Three dimensional geometry is implied from its comparison with the line-of-sight wind velocity determined from half-widths of submillimeter emission line profiles of abundant molecules. Uneven temporal variations in brightness for different searchlight beams and anisotropic distribution of extended halo are revisited in the context of the stellar light illumination through a porous envelope with postulated longer-term variations for a period of 10 years.

• IEIE Transactions on Smart Processing and Computing
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• 제6권4호
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• pp.269-275
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• 2017

Automatic vehicle detection is a very important function for autonomous vehicles. Conventional vehicle detection approaches are based on visible-light images obtained from cameras mounted on a vehicle in the daytime. However, unlike daytime, a visible-light image is generally dark at night, and the contrast is low, which makes it difficult to recognize a vehicle. As a feature point that can be used even in the low light conditions of nighttime, the rear lamp is virtually unique. However, conventional rear lamp-based detection methods seldom cope with atypical lamps, such as LED lamps, or flashing turn signals. In this paper, we detect atypical lamps by blurring the lamp area with a low pass filter (LPF) to make out the lamp shape. We also propose to detect flickering of the turn signal lamp in a manner such that the lamp area is vertically projected, and the maximum difference of two paired lamps is examined. Experimental results show that the proposed algorithm has a higher F-measure value of 0.24 than the conventional lamp pairing-based detection methods, on average. In addition, the proposed algorithm shows a fast processing time of 6.4 ms per frame, which verifies real-time performance of the proposed algorithm.

• Journal of Microbiology and Biotechnology
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• 제9권4호
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• pp.475-481
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• 1999

The study of lignin, a major component of secondary cell wall, has been partly focused on its removal from the woody part in the kraft pulping industry. Cinnamyl alcohol dehydrogenase (CAD; EC 1.1.l95) catalyzes the synthesis of cinnamyl alcohols from corresponding cinnamaldehydes. A cDNA clone, MdCADl, encoding putative CAD from apples (Malus domestica Borkh. cv Fuji) was characterized in this study. The clone contains an open reading frame of 325 amino acid residues, which shows a greater than 80％ identity with Eucalyptus CADl. MdCADl mRNA was detectable in vegetative tissues and was strongly expressed in the fruit. The expression pattern of MdCADl mRNA in the fruit peel after light exposure was also examined. The mRNA was rapidly increased until 1 day after light exposure and remained stable thereafter, suggesting that MdCADl is light inducible. The inducibility of the MdCADl gene was examined using several environmental stresses. Mechanical wounding of leaves increased the MdCADl mRNA level and the induction was further increased by salicylic acid. Southern blot hybridization showed that there is either one or a few copies of CAD genes in apples. To our knowledge, it is believed that MdCADl is the first CAD clone expressed predominantly in fruit.

• International Journal of Control, Automation, and Systems
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• 제6권5호
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• pp.740-745
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• 2008

This paper presents a new non-contact 3D robotic inspection system to measure the precise positions of screw and punch holes on a car body frame. The newly developed sensor consists of a CCD camera, two laser line generators and LED light. This lightweight sensor can be mounted on an industrial robot hand. An inspection algorithm and system that work with this sensor is presented. In performance evaluation tests, the measurement accuracy of this inspection system was about 200 ${\mu}m$, which is a sufficient accuracy in the automotive industry.

• Asian Journal for Public Opinion Research
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• 제8권2호
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• pp.126-143
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• 2020

Since 2008, strategic partnerships have been established between China and Korea. From 2009 to 2019, the bilateral relationship kept a generally stable rate of development with conflicts and uncertainties. It is necessary to study national image construction in the respective mainstream media of the two countries. The present study analyzed Korea-related reports (N = 744) in the People's Daily from 2009 to 2019, aiming to examine the Korean national image framing under Fairclough's three-dimensional Critical Discourse Analysis (CDA) framework: "whatness," "how," and "whyness." The results shed light on what the Korean national image in the People's Daily was and how and why it was framed in that way. This study provided some implications for readers to further recognize the role that media play in constructing a particular image of one country and a frame for researchers to study foreign national image framing in one of China's mainstream newspapers.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
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• pp.479-482
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• 2000

To complite the high speed cutting system, It should be solved some problems, to make light the weight of mechanism for feedrate, develop the Linear motor that bas more power, high speed control system, and high speed cutting tools, nowadays, although many high speed cutting machine is to be built by some machine maker ,they have same problems, in this study, developed the system ball screw type before the feedrate mechanism for linear motor ,so we make the basic system for Line Cents . through that, it is limited to reduce the weight of frame and their frame is to be designed differently each other to reach the purpose special material or strucutre should be contrived.