• Journal of Welding and Joining
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• v.33 no.1
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• pp.30-34
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• 2015

Residual stresses are inherently introduced into the engineering components during manufacturing including rolling, forging, bending and welding processes. Excessive residual stresses are known to be detrimental to the proper integrity and performance of components. Neutron diffraction has become a well-established technique for the determination of residual stresses in welds. The deep penetration capability of neutrons into most metallic materials makes neutron diffraction a powerful tool for the residual stress measurements through the thickness of the weld specimen. Furthermore, the unique volume-averaged bulk characteristic of the scattering beam and mapping capability in three dimensions is suitable for the engineering purpose. In this presentation, the neutron diffraction measurements of the residual stresses will be introduced and measurement results will highlighted in thick weld plates.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.04a
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• pp.662-668
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• 1997

Since the structural impedance is much greater than that of medium in the most cases, we often assume that the structure is rigid and that the structural vibration is independent of medium, i.e. we usually calculate the vibration of the structure first, and then obtain the radiation sound from it. This assumption is no longer satisfied when the structural stiffness is small or the fluid impedance is comparable to it. This situation often happens in underwater acoustics. Although many researchers have studied about structural-fluid coupling, we have difficulties in solving the problem analytically. Therefore the numerical method using powerful computation leads us to obtain the various coupling problem. To understand the physical coupling phenomena, visualization of sound field by a geometrically simple system(plate-cavity coupled system) is performed experimentally. Acoustic holographic method is used to estimate sound field.

• Journal of the Korean Vacuum Society
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• v.13 no.4
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• pp.164-174
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• 2004

Computer control of experiments is very powerful because computer can outperform human being for most routine and repeated procedures. We successfully made the whole process of sputtering and annealing fully automated and controllable through network. The present work shows a possibility of building unmanned laboratory.

• International Journal of Aeronautical and Space Sciences
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• v.5 no.2
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• pp.28-34
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• 2004

One of the major problem encountered in nuclear plants and satellites design isEMI (Electro-Magnetic Interference) and EMC (Electro-Magnetic Compatibility).Here, our focus is to implement the test board for checking SEU (Single EventUpsets); the effects of protons on the electronic system. The SEU results from thelevel change of stored information due to photon radiation and temperature in thespace environment. The impact of SEU on PLD (Programmable Logic Devices)technology is most apparent in ROM/SRAM/DRAM devices wherein the state ofstorage cell can be upset. In this paper, a simple and powerful test techniques issuggested, and the results are presented for the analysis and future reference. In ourexperiment, the proton radiation facilitv (having the energy of 50 MeV with a beamcurrent of 60 uA of cyclotron) available at KIRAMS (Korea Institute of RadiologicalMedical Sciences) has been applied on a commercially available SRAM manufacturedby Hynix Semiconductor Company.

• Agribusiness and Information Management
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• v.2 no.1
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• pp.31-73
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• 2010

On-line shopping mall has become a powerful marketing tool recently. On-line shopping malls provide information for consumers about goods and influence the decision-making process of purchasers. Therefore many local government made on-line shopping malls for advertising agricultural production in the region. However, in the face of problems related with effectiveness on shopping mall management, most of on-line shopping malls has been managing by private sector actually. This study aims to propose the plans for development of the on-line shopping malls. For this purpose, this study investigated current management status of the shopping malls and conducted case study on-line shopping malls.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.6
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• pp.1565-1585
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• 2012

The characteristics of ad hoc networks, such as the absence of infrastructure, a dynamic topology, a shared wireless medium and a resource-constrained environment pose various security challenges. Most previous studies focused on the detection of misbehavior after it had occurred. However, in this paper we propose a new way of thinking to evade the occurrence of misbehavior. In our scheme, we firstly present a clustering algorithm that employs a powerful analytic hierarchy process methodology to elect a clusterhead for each cluster. The clusterhead in each cluster is then allowed to assign the backoff values to its members, i.e., originators, rather than permitting the originators to choose the backoff values by themselves. Through this media access control layer misbehavior detection mechanism, the misuse of the backoff in the media access control layer in the 802.11 distributed coordination function can be detected.

• Journal of the Korean Home Economics Association
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• v.36 no.12
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• pp.1-9
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• 1998

The relations of personality characteristics, such as shyness, sociability and self-disclosure and victimization by peers to loneliness in adolescents were examined with a sample of 485 second-grade highschool students(256 boys and 229 girls). They answered the questionnaires on loneliness as well as shyness, sociability, self-disclosure, and victimization by peers. All variables were significantly related to loneliness. The more shy they were and the more victimization by peers they experienced, the more lonely they were. The more sociable they were and the more self-disclosure they showed, the less lonely they were. All variables significantly predicted loneliness and the most influential predictor of loneliness was victimization by peers, indicating that the influence of victimization by peers on loneliness is so powerful for the adolescents.

• Journal of the Korean Home Economics Association
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• v.43 no.6 s.208
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• pp.37-46
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• 2005

Advertising is the most powerful marketing communication tool. Fashion magazines are a popular media for fashion advertising because of their multi-color visual printing. In this study, the interest in and attitude toward fashion advertising were investigated with high school girls in Seoul, along with their interrelation with buying experience and post-purchase satisfaction. The consciousness of the endorser and the fashion of celebrities both increased with rising interest in fashion advertisement. However, the brand orientation showed no relationship with the interest in fashion advertisement. The interest in fashion advertisement was useful to explain buying experience with limited variance. The correlation between brand orientation and buying experience increased with rising interest in fashion advertisement, indicating that those with little interest in fashion advertisement showed strong dependence on brand loyalty. Those with more interest in fashion advertisement counted distinctive aspects of fashion advertisement more seriously. Affective aspects of fashion advertisement showed a correlation with buying experience and post-purchase satisfaction.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.95.2-95.2
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• 2011

The most powerful technique for deducing the magnetic structure of the Sun is spectro-polarimetry. Detailed measurements of the polarization signal of the spectral lines (Stokes vector) allow us to infer the physical conditions in the solar atmosphere prevailing during the line formation. Inversion codes are the main tool to extract this information from the Stokes spectra. This study will focus on measurements of the chromospheric He I 1083.0 nm triplet and the photospheric Si I 1082.7 nm line. A spectropolarimetric data set of sunspots, obtained with the German Vacuum Tower Telescope (VTT) at the Teide observatory on Tenerife, is analyzed using an inversion technique. We will introduce the German Vacuum Tower Telescope and the inversion code HeLix, and will show data sets that are analyzed by HeLix.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.3
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• pp.721-730
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• 1996

In this paper, a new test criterion for binary decision problems is proposed. The integrated power flunction over a parameter interval is first itroduced as an extension of the power function. The concept of the most integrated powerful (MIP) test based on the integrated power function is then introduced. The MIP criterion is to masimize the value of the integrated power function in any paricular parameter interval. As an applicationof the MIP test, the known signal detection problem is considered. The test statistic of the MIP detector for known signals is obtained and an approximation to the MIP test statistic is also considered.