• Journal of The Korean Association For Science Education
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• v.24 no.2
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• pp.408-415
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• 2004

The purpose of this study is to investigate the effect of the delayed resolution of cognitive conflict on middle school students' conceptual change in learning the concept of the action and reaction with cognitive conflict strategy. The subjects were divided into 3 groups according to the time in which teacher tried to resolve cognitive conflict: instant resolution group, 2-day delay resolution group, and 7-day delay resolution group. Pretest, just before test, posttest, and delayed posttest were examined to measure the degree of conceptual change. Delay resolution groups' students answered the questionnaire asking what they had done to resolve cognitive conflict during the period which had been delayed resolution of cognitive conflict. The results of this study were as follows. First, instant resolution group showed significantly more scientific conceptual change than delay resolution groups. Secondly, most of delay resolution groups' students who tried to resolve cognitive conflict interacted with their peers. Also, delayed resolution of cognitive conflict was not helpful to resolve cognitive conflict. Thirdly, in delay resolution groups, we found the tendency that students who spent more than 30 minutes trying to resolve cognitive conflict altered their preconceptions into scientific concepts more easily than the others did. According to the results of this study, instant resolution of cognitive conflict is more effective on scientific conceptual change than delayed resolution of cognitive conflict.

• Journal of the Korea Institute of Building Construction
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• v.16 no.6
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• pp.553-560
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• 2016

Wage is a very important issue not only for the workers' current living but also for the future laboring landscape. As of 2014, it is reported that about 290,000 workers suffer from delay in payment of wage. The construction industry is particularly labor-intensive, which implies that delay in payment of wage is a serious problem. Despite this fact, in terms of the delayed payment of wage most studies have been conducted on the improvement of a system to resolve delayed payment in exclusion of labor workers' awareness and thinking. Thus, the purpose of this study is to understand construction labor' awareness and analyze the effectiveness of the resolution step of the delayed payment of wage based on construction labors' awareness. In the research result, more than 30 percent of all construction labors and managers are never aware of the settlement procedure of the delayed payment, and it appears that the resolution step system needs to be greatly improved. In conclusion, it is expected that this study will be utilized as fundamental data for the settlement procedure of the delayed payment, and the influence of delayed payment on construction labors' safety behavior and productivity should be further studied in the future.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.3
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• pp.31-38
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• 2004

The wavelength variation of a scanned fiber laser is analyzed using quadrature sampling technique. By time delayed sampling of a phase modulated Mach-Zender interferometer, the wavelength information can be precisely determined regardless of the nonlinearity in the Fabry-Perot wavelength filter which scanned the fiber laser. A wavelength readout resolution of ～20 pm was obtained at 2 KHz M-Z modulation frequency, and it was shown that the resolution could be improved in case of using an electro-optic phase modulator.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.1
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• pp.48-54
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• 2009

Purpose: There are few studies evaluating the usefulness of dedicated high-resolution scintimammography and no studies using delayed washout with this dedicated high resolution scintimammography for the evaluation of breast lesions. We underwent this study to evaluate the clinical usefulness of Tc-99m MIBI in evaluating patients with palpable breast lesions using dedicated high-resolution scintimammography. Materials and Methods: This study included 19 patients with 23 palpable breast lesions who underwent mammography. Tc-99m MIBI was taken to further characterize these lesions. Scintimammography images were acquired with standard craniocaudal and mediolateral oblique views and delayed images were additionally taken. Final conclusions were based on histopathology, either by biopsy or mastectomy results. Results: Eighteen lesions were malignant and five were benign. Mammography was indeterminate for thirteen lesions, nine of those were malignant. Mammography also categorized one lesion as benign in a dense breast, but scintimammography and pathology results showed malignancy. Of the five benign lesions, two were visible on scintimammography, but delayed images showed washout. Conclusion: Based on our preliminary results, dedicated high resolution scintimammography seems to be very useful in characterizing palpable lesions that were indeterminate or negative on mammography.

• Journal of the Korean Chemical Society
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• v.44 no.4
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• pp.328-336
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• 2000

The pulsed-delayed extraction (PDE) in linear time-of-flight mass spectrometer(TOF MS) is characterized on the enhancement of resolution, mass-depth of focus and effect of instrumentahan 2000. The ion signals separate isotopically by up to molecular weight of 2500 in instrumental broadening of 5 ns, which is a good agreement with calculation. The fragmentation paths of PPG can be sug-gested by the isotopica distributions of fragment series produced when PPG desorbed from graphite surface.

• Journal of computational fluids engineering
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• v.17 no.4
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• pp.24-31
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• 2012

Effects of the subgrid length-scale in the Delayed-Detached Eddy Simulation(DDES) are investigated based on the Spalart-Allmaras(S-A) and the k-$\omega$ Shear Stress Transport(SST) turbulence models. Driver & Seegmiller's experimental results are used to validate numerical results. Grid convergence with grid resolution and subgrid length-scale is investigated. The simulation results show that the volume method for the subgrid length-scale is more resistant to unfavorable effects of the grid size in the periodic direction than the maximum method. Using a sufficient grid resolution and an appropriate subgrid length-scale, both S-A based DDES and SST based DDES methods can provide a good correlation with the experimental data.

• Proceedings of the Optical Society of Korea Conference
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• 1989.02a
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• pp.55-58
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• 1989

The methods of recording transient phenomena with picosecond or better resolution fall into two basic categories: those in which the detector itself prossesses adequate time resolution for the task at hand, and those in which the response of the system is sampled by examining the characteristics of a second pulse ("the probe") delayed in time from the initiating pulse ("the pump") as a function of time delay between pump and probe cases. In this case the time resolution is only limited by the pump-and probe-pulse durations. As an application of this time-resolved spectroscopic technique, the ultrafast orientational relaxation phenomena of the dye molecules are currently under investigation in our laboratory. In this presentation the status of our experiment is summarized.iment is summarized.

• The Journal of Engineering Geology
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• v.3 no.2
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• pp.167-176
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• 1993

The high resolution studies for shallow seismic reflection are carried out using 24-channel seismograph and the high sensitivity geophone(50-500Hz). In order to study the underground structures such as small faults, fractures, cracks and cavities, it is of great importance to enhance high resolution of the seisrnic records for the targets vertically and laterally. In analysis of high resolution seismic reflection, Nyquist frequency($F_N$) should be lager than the highest frequency in the records and the highest wave number should not be exceed the Nyquist wave number($1/2{\Delta}x$). The highest frequency above the Nyquist will be removed using low pass filter or antialias filter. The trace interval Ax should be taken into account so that the highest wave number(f/v) can be less than $1/2{\Delta}x$. The Fraunhofer diffraction of a hyperbola seismic section above the tunnel appeares on the common offset method, and little first arrivals of direct wave on the single-end shooting, delayed strong impulsive reflections are also shown above the tunnel. Ray Method(Cherveney and Psencik, 1983) also represents the same results that the reflected waves from the tunnel are delayed and single impulsive with little first arrivals, while transrnitted waves through the tunnel are delayed with low frequency.

• Journal of Arbitration Studies
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• v.11 no.1
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• pp.217-245
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• 2001

Like traditional commerce, disputes are bound to arise in the course of conducting an e-commerce transaction. At present of June 30, 2001, 259 cases of dispute on e-commerce have been applied for the mediation of Electronic Transaction Dispute Mediation Committee, types of them are 170 cases of delayed delivery of commodity, 21 cases of contract cancellation and refund, 16 cases of personal information protection, 16 cases of false and exaggerated advertisement, 14 cases of commodity defect. The settlement systems of e-commerce dispute are litigation and Alternative Dispute Resolution(ADR). ADR encompasses mediation, arbitration, and similar private tools for resolving disputes. ADR offers many perceived advantages. Speed of resolution and low cost are often cited as the primary benefits. Therfore e-commerce disputes may be settled more effectively by litigation. The settlement systems of e-commerce dispute by ADR are the mediation of Electronic Transaction Dispute Mediation Committee, the mediation of Consumer Dispute Mediation Commercial Arbitration Board, and the arbitration of Korean Commerical Arbitration Board. E-commerce sets up the probability that its merchants and customers will not exist in the same legal jurisdictions. The confusing application of laws and wide geographical dispersion of these parties will necessitate a faster and cheaper dispute resolution methodology. Therefore, online ADR may be effective for e-commerce dispute resolution. The examples of online ADR opetation are the cyber mediation of Electronic Transaction Dispute Resolution Committee, the cyber mediation of Korean Commercial Arbitration Board, the cyber mediation of Click N Settle, the online ADR of BBB online, and the cyber arbitration of virtual Magistrate.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.104-109
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• 2014

Purpose: Conventional pinhole scintigraphy offers a high resolution and generally use for thyroid scan or bone scintigraphy. the aim of this study is to evaluate performance of each aperture according to the diameter size. Materials and Methods: In this study 2 mm, 4 mm, 6 mm, 8 mm diameter pinhole collimators were mounted on Siemens E.CAM systems. In order to evaluate performance evaluation of each aperture, we acquired projection image by using SPECT for evaluating FWHM, resolution test and static image for evaluating thyroid phantom test. Results: As a result of FWHM showed 2.2 mm FWHM, 3.2 mm FWHM, 5.4 mm FWHM, 7.5 mm FWHM per each aperture in the resolution test. SNR, uniformity, contrast were acquired result from thyroid phantom test comparing general image and delayed image. as a result of SNR showed 6.55, 8.47, 6.2, 5.23 in case of general image and 5.25, 5.01, 5.38, 5.82 in case of delayed image per each aperture. as a result of uniformity showed 0.152, 0.118, 0.161, 0.19 in case of general image and 0.19, 0.199, 0.185, 0.171 in case of delayed image per each aperture. as a result of contrast showed 1.31, 1.19, 1.15, 1.01 in case of general image and 1.09, 1.08, 1.04, 1 in case of delayed image per each aperture. Conclusion: Resolution and sensitivity were heavily influenced by aperture size. and also we found advantage of delayed image as a result of thyroid phantom test.