• Korean Journal of Materials Research
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• v.4 no.6
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• pp.681-686
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• 1994

Microwave Detector Using $YBa_{2}Cu_{3}O_{7-x}$, Grain Boundary Junction $YBa_{2}Cu_{3}O_{7-x}$ superconductor thin films were deposited on $LaAIO_{3}$ (100) single crystal substrates using a metal organic chemical vapor deposition (MOCVD) method. These films showed the critical temperature of about 9OK and critical current density of over $10^5/A \textrm{cm}^2$at 77K. These films showed granular structure with 0.5~1.5$\mu \textrm{m}$ grains. Bridge-type junctions, 6$\mu \textrm{m}$ in width and 6pm in length, were fabricated using the photolithography and the Ar ion milling techniques. Current-voltage (I-V) characteristics of these junctions with the microwave irradiation at 77K were studied. The critical current densities decreased as the irradiated microwave power increased. When microwaves were irradiated on the bridge at 77K. the I-V charateristics showed constant voltage stcp(Shapiro steps) at $\Delta$=nho/2e.

• Journal of Ocean Engineering and Technology
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• v.10 no.3
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• pp.138-152
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• 1996

Many studies of heat transfer on the swirling flow or unswirled flow in a abrupt pipe expansion are widely carried out. The mechanism is not fully found evidently due to the instabilities of flow in a sudden change of the shape and appearance of turbulent shear layers in a recirculation region and secondary vortex near the corner. The purpose of this study is to obtain data through an experimental study of the swirling flow and heat transfer downstream of an abrupt expansion in a circular pipe with uniform heat flux. Experiments were carried out for the turbulent flow nd heat transfer downstream of an abrupt circular pipe expansion. The uniform heat flux condition was imposed to the downstream of the abrupt expansion by using an electrically heated pipe. Experimental data are presented for local heat transfer rates and local axial velocities in the tube downstream of an abrupt 3:1 & 2:1 expansion. Air was used as the working fluid in the upstream tube, the Reynolds number was varied from 60, 00 to 120, 000 and the swirl number range (based on the swirl chamber geometry, i.e. L/d ratio) in which the experiments were conducted were L/d=0, 8 and 16. Axial velocity increased rapidly at r/R=0.35 in the abrupt concentric expansion turbulent flow through the test tube in unswirled flow. It showed that with increasing axial distance the highest axial velocities move toward the tube wall in the case of the swirling flow abrupt expansion. A uniform wall heat flux boundary condition was employed, which resulted in wall-to-bulk temperatures ranging from 24.deg. C to 71.deg. C. In swirling flow, the wall temperature showed a greater increase at L/d=16 than any other L/d. The bulk temperature showed a minimum value at the pipe inlet, it also exhibited a linear increase with axial distance along the pipe. As swirl intensity increased, the location of peak Nu numbers was observed to shift from 4 to 1 step heights downstream of the expansion. This upstream movement of the maximum Nusselt number was accompanied by an increase in its magnitude from 2.2 to 8.8 times larger than fully developed tube flow values.

• Journal of the Korean Institute of Gas
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• v.18 no.1
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• pp.46-51
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• 2014

The purpose of this paper is to study of the vehicle lamp manufacturing system composing ultrasonic waves connection process. Making lamp assembly plant, it was produced in the separate process as the injection molding, ultrasonic waves bonding, annealing in the constant temperature, lamp assembling and packing. But the improvement method producing the lamp was added with one-step process by one automation technique. As a result, welding with ultrasonic waves process, the method decreased the energy consumption and noise during ultrasonic waves welding. Therefore, this method used the mathematics modeling for checking validity, it selected the stability and suitable controller using transfer function of plant and bode chart. In this study, the $180^{\circ}$ revolution control system to turn injection part upside down was $M_{eq}\;lcos{\theta}(t)$ because of gravity influence. It effected to unstable condition a system. For solving this problem, it aimed the linearization and stabilization of system by elimination $M_{eq}\;lcos{\theta}(t)$ as applying Free-forward control technique.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.4
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• pp.34-40
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• 2004

In this paper, we have studied the OCT(Optical Coherence Tomography) system which has been advantages of high resolution, 2-D cross-sectional images, low cost and small size configuration. The characteristics of light source determine the resolution and coherence length. The light source has a commercial SLD with a central wavelength of 1,285 ill11, 35.3 nm(FWHM). The optical delay line is necessary to make equal with the optical path length to scattered light or reflected light from a sample. In order to make equal the optical path length, the stage that is attached to a reference mirror is controled by a step motor. And the interferometer is configured with the Michelson interferometer by using a single mode fiber, and the scanner can be focused on the sample by using a reference ann Also, the 2-dimension cross-sectional images were measured with scanning the transverse direction of the sample by using a step motor. After detecting the internal signal of lateral direction, a scanner is moved to obtain the cross-sectional image of 2-dimension by using step motor. A photodiode, which has high detection sensitivity and excellent noise characteristics has been used. The detected small signal has a noise and interference. After filtering and amplifying the signal, the output signal is demodulated the waveform And then, a cross-sectional image is seen through converting this signal into a digitalized signal by using an AID converter. The resolution of the sample is about 30${\mu}{\textrm}{m}$, which corresponds to the theoretical resolution. Also, the cross-sectional images of onion cells were measured in real time scheme.

• Journal of Broadcast Engineering
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• v.21 no.6
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• pp.845-860
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• 2016

This paper proposes a digital watermarking scheme to protect the ownership of the freeview 2D or 3D image such that the viewer watches the image(s) by rendering a arbitrary viewpoint image(s) with the received texture image and its depth image. In this case a viewpoint change attack essentially occurs, even if it is not malicious. In addition some malicious attacks should be considered, which is to remove the embedded watermark information. In this paper, we generate a depth variation map (DVM) to find the locations less sensitive to the viewpoint change. For each LH subband after 3-level 2DDWT for the texture image, the watermarking locations are found by referring the DVM. The method to embed a watermark bit to a pixel uses a linear quantizer whose quantization step is determined according to the energy of the subband. To extract the watermark information, all the possible candidates are first extracted from the attacked image by considering the correlation to the original watermark information. For each bit position, the final extracted bit is determined by a statistical treatment with all the candidates corresponding that position. The proposed method is experimented with various test images for the various attacks and compared to the previous methods to show that the proposed one has excellent performance.

• The Journal of the Korea Contents Association
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• v.14 no.3
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• pp.186-194
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• 2014

The purpose of this paper is to review the meaning of extended application of workers' compensation for artists. This study explains by giving specific two examples. The first case is about broadcasting extra who is permitted to receive compensation from Korea Workers' Compensation & Welfare Service without filing a suit. Whereas, The second case is about musical stage crew who is not permitted to obtain compensation for accident during work. The reason why he could not receive compensation is not because he is regarded as worker, but because he is regarded as individual businessman. Extended application of workers' compensation for artists could be a double-edged sword for workers through two cases. Firstly, Broadcasting extras could become much easier to receive workers' compensation according to precedent. Secondly, It is more difficult to get the workers' compensation by the reason of not applying for workers' compensation admission like the second case, even though the second case of forms of employment is similar to that of the first. In other words, New compensation development could generate another obstacles to enter compensation systems. Extended application of workers' compensation should be operated with covering artists' compensation case by case.

• Journal of the Korean Society for information Management
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• v.24 no.3
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• pp.5-19
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• 2007

Organizations are investing in information systems for an ever-increasing number of end-user tasks. Extracting benefit from these investments increasingly depends on supporting effective use or information center and satisfying information center users. Information center is information intensive and the use of advanced technology may support user for delivering an unique capabilities in an organization. Information center represents an important source which seems very well suited for end-users support investigation. This research explores the end-user support factors that correlate with user satisfaction in information center. To exam user satisfaction, information supporting, service reliability, and system capabilities were identified as potential predictors of end-user support satisfaction at information center. Three hypotheses have been tested with the survey or 252 end-users examines 18 potential end-user support factors such as information supporting, service staff attitude, and system capabilities at information center. Service quality gap between perceived Importance and performance for each support factor, is computed. The relationship between these service quality gaps and user satisfaction are tested. This study presents that the level of information supporting, service reliability, and system capabilities are significantly to user satisfaction, and it is influenced by the extent of service quality gap between perceived importance and performance for each support tactor.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.1
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• pp.70-77
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• 2005

The study was results obtained from the trial make of the hybrid GPS-electromagnetic(EM) compass which overcome shortcoming of GPS compass and EM compass. The results were summarized as follows: GPS compass detected the stable ship's heading at 0.1^{\circ}$ intervals with the turning angular velocity of less than 25^{\circ}$/sec in the experiment for the characteristics of turning angular velocity with stepmotor, but in case of over 25^{\circ}$/sec the compass did not detect it. On the contrary, the EM compass always indicated the ship's heading with no connection of the turning angular velocity, however the compass is low accuracy compared with GPS one owing to a compass error. The ship's headings by the hybrid GPS-EM compass were displayed at fixed point and moving by car; if the GPS compass work the headings were displayed by GPS compass, if not, the heading is provided stably by adding or subtracting of a compass error to the heading of EM compass. Also, each ship's heading was derived from not only the GPS compass but also the EM one by add or subtract of the compass errors, and then was worked covariance for the analogy. The results show that the ship's heading of two compasses has been verified the similarity to 95% confidence level.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.7
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• pp.362-374
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• 2018

The purpose of this study is to identify and improve the satisfaction of people attending the Jeju International Wind Festival, the representative festival in Jeju. The Jeju International Wind Ensemble Festival is a festival in which people communicate with each other through music. The objective of this study is to investigate user satisfaction of the International Wind Ensemble Festival and to make improvement plans. The average satisfaction rate for the event was 75.8% (Satisfaction + Great satisfaction). In addition, the average program level of the Jeju International Wind Ensemble Festival and average appropriateness of the event space were 86.9% (Satisfaction + Great satisfaction) and 85.2% (Satisfaction + Great satisfaction), respectively. The disadvantage is that public transportation that should be improved. According to results of the survey through the interview, the town wind ensemble festival and outside concert enabled performers to communicate with the audience through melody. In order for the Jeju International Orchestra Festival to take root as a festival for citizens, it is necessary to increase the convenience of transportation, secure personnel in charge of the secretariat, revitalize the Jeju International Orchestra Festival website, and promote volunteer activities. We present future research direction.

• Cartoon and Animation Studies
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• s.31
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• pp.227-248
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• 2013

With the advancement of computers, opening title sequences in movies are continuously improving. Initially, titles and opening credits were created using what is called the optical method, whereby text was photographed on separate film and then copied onto the movies film negative. In contemporary movie making, however, the title sequence may be seamlessly integrated into the beginning of the movie by an insertion method that not only allows for more diverse technical expression, including the use of both 2D and 3D graphics, but also for its emergence as an independent art form. As such a title sequence, in as little as 50 seconds or up to 10 minutes, is able to convey the films concept while also suggesting more implicit intricacies of plot and thereby eliciting greater interest in the movie. Moreover, according to the directors intent and for a variety of purposes, the title sequence, while maintaining its autonomy, is inseparable from the movie as an organic whole; therefore, it is possible to create works that are highly original in nature. The purpose of this study is to analyze the kinetic typography that appears in title sequences of ten films produced by the Korean entertainment industry in 2012. Production techniques are analyzed in a variety of ways in order to predict the future direction of opening title sequences, as well as present aesthetic and technical models for their creation.