• Applied Chemistry for Engineering
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• v.35 no.1
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• pp.16-22
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• 2024

Polymer electrolyte membrane fuel cells have the advantage of low operating temperatures and fast startup and response characteristics compared to others. Simulation studies are actively researched because their cost and time benefits. In this study, the resistance of water residual in the gas diffusion layer (GDL) of the unit cell was added to the existing equation to compare the actual data with the model data. The experiments were conducted with a 25 cm² unit cell, and the samples were separated into stopping times of 0, 10, and 60 minutes following primary impedance measurement, activation, and polarization curve data acquisition. This gives 0, 10, and 60 minutes for the residual water in the GDL to evaporate. Without the rest period, the magnitude of the performance improvement was not significantly different at the same potential and flow rate, but the rest period did improve the performance of the membrane electrode assembly when measuring impedance. By changing the magnitude of the resistance reduction to an overvoltage, the voltage difference between the fuel cell model with and without residual water was compared, and the error rate in the high current density region, which is dominated by concentration losses, was reduced.

• Geophysics and Geophysical Exploration
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• v.27 no.3
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• pp.159-170
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• 2024

The bioreactor method, in which leachate is reinjected into a landfill for rapid decomposition and stabilization of buried waste, is being applied and tested at many landfills because of its numerous advantages. To apply the bioreactor method to a landfill successfully, it is very important to understand the behavioral characteristics of the injected leachate. In this study, electrical resistivity monitoring was performed to estimate the behavior of a landfill leachate in Korea where the bioreactor method was applied. For the electrical resistivity monitoring, a baseline survey was conducted in August 2013 before the leachate was injected, and time-lapse monitoring surveys were conducted four times after injection. The electrical resistivity monitoring results revealed reductions in electrical resistivity in the landfill attributable to the injected leachate, and the change in its characteristics over time was confirmed. In addition, by newly defining the electrical resistivity change ratio and applying it in this study, the spatial distribution and behavior of the leachate over time were effectively identified. More research on optimization of data acquisition and integrated monitoring methods using various techniques should be conducted in the near future.

• The Journal of Korean Society for Radiation Therapy
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• v.20 no.2
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• pp.83-89
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• 2008

Purpose: The checking method of target and normal structure are used by MVCBCT, KVCBCT, CT On-rail System, Ultrasound in H&N cancer patient. In case of MVCT, the utilization of bone structure is valuable to check around tissue. But the utilization of soft tissue is not enough. The point of this paper is dose variation in movable parotid and changeable volume of H&N cancer patient of CT On-rail System. Materials and Methods: The object of H&N cancer patient is 5 in this hospital. The selected patient are scanned ARTISTE CT Vision (CT On-ral System) a triweekly. After CT scanning, tranfered coordinates are obtained by movable of parotid gland comparison with planning image. Checking for the changeable volume of parotid gland. A Obtained CT image are tranfered to the RTP System. So dose variation are checked by following changed volume. Results: The changes of target coordinate by the parotid gland movement are X: -0.4~0.4 cm, Y: -0.4~0.3 cm, Z: -0.3~0.3 cm. the volume of GTV is decreased to about 7.11%/week and then both parotid gland volume are shrinked about 4.81%/week (Lt), 2.91%/week (Rt). At the same time, each parotid gland are diminished in radiation dose as 3.66%/week (Lt), 2.01%/week. Conclusion: Images from CT on the rail System which are able to aquire the better quality images of soft tissue in Target area than MVCBCT. After replanning and dose redistribution by required images, It could gain not only the correction of the patient set-tup errors but exact dose distribution. Accordingly, the delivery of compensated dose, It makes that we could do Adaptive Targeting Radiotherapy and need Real Time Adaptive Targeting Radiotherapy by reduce beam delivary time.

• Journal of Digital Convergence
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• v.10 no.10
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• pp.301-306
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• 2012

We propose a method for accurate image acquisition in a machine vision system in the present study. The most important feature is required by the various lenses to implement real and of the same high quality image-forming optical role. The input of the machine vision system, however, is generated due to the aberration of the lens distortion. Transformation defines the relationship between the real-world coordinate system and the image coordinate system to solve these problems, a mapping function that matrix operations by calculating the distance between two coordinates to specify the exact location. Tolerance Focus Lens caused by the lens aberration correction processing to Galvanometer laser precision machining operations can be improved. Aberration of the aspheric lens has a two-dimensional shape of the curve, but the existing lens correction to linear time-consuming calibration methods by examining a large number of points the problem. How to apply the Bilinear interpolation is proposed in order to reduce the machining error that occurs due to the aberration of the lens processing equipment.

• Journal of KIISE
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• v.43 no.5
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• pp.606-612
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• 2016

The multi-view video service based on the DASH(Dynamic Adaptive Streaming over HTTP) switches the viewpoint or object which is selected by the user among the multiple video streams captured by multiple cameras. However, the problem is that the conventional DASH-based multi-view video service takes a long time to switch the viewpoint. The reason is that the conventional scheme switches to the new video stream after consuming all buffered segments of the previous video stream. In this paper, we propose a video streaming scheme for minimizing the viewpoint switching delay in the DASH-based multi-view video service. In order to minimize the viewpoint switching delay, the proposed scheme configures the video streams by controlling the GoP (Group of Pictures) size and controls the client buffer based on bandwidth estimation and playback buffer occupancy. Through the experimental results, we prove that the proposed scheme reduces the viewpoint switching delay.

• Journal of Global Scholars of Marketing Science
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• v.6
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• pp.313-337
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• 2000

오늘날 병원마케팅에서 간호서비스는 병원 내 어느 전문직보다도 가장 많은 시간을 고객인 환자와 합께 나누며 환자의 욕구 충족을 위하여 고도의 분업화된 제반 부서들간의 활동을 조정하고 융화시키는 역할올 통하여 환자들이 지각하는 병원서비스의 만족도에 종요 한 부분을 차지하고 있으므로 병원마케팅의 전략적 초점으로 전환될 필요가 있다. 의료 서비스는 특성상 전문성이 강해서 정보가 소비자에게 공유되지 못하고 있으며 비영리조직이라는 인식하에 의료 서비스에 대한 광고를 제한합으로써 실제적으로 소비자에게 필요한 의료 관련 정보들마저도 제한을 받는 경우가 많이 있다. 그리고 의료서비스의 무형성, 비분리성, 이질성, 소멸성의 특성으로 어떠한 의료 서비스를 이용할 것인지해 대한 결정을 고객이 하기 어렵기 때문에 오늘날 의료 소비자들이 의료제공 기관을 선택 할 때는 밑올만한 다른 사랑의 추천에 크게 의존하고 있는 것으로 알려져 있으며, 국내의 연구에서도 의료소비자들이 병원을 선택하는 주된 정보 획득 원천이 주변의 제 3자인 것으로 알려져 있다. 이러한 정보 전달에 구전 커뮤니케이션이 주요한 제3자적 억할을 한다. 이러 한 관접에서 불 때 의료 소비자둘 사이의 구전 커뮤니케이션은 마케 팅 전략상 매우 종요하 며 마케팅 관리측면에서 의료 소비자들의 구전 커뮤니케이션 형태톨 파악하는 것은 매우 중요한 일이라고 할 수 있다. 이에 본 연구는 구전 커뮤니케이션의 내용 및 경로 그리고 유형을 파악하고 이들 유형간 의료서비스의 만족도를 알아봄으로써 효파적인 병원 마케팅 전략을 수립하는데 필요한 자료를 제공하고자 한다. 본 연구의 결과를 증합해 보면 의료소비자들이 연령 성별 학력, 소득, 직업, 주거지가 비슷한 사람과 구전이 활발하게 일어냐는 것을 파악 할 수 있어 특히 상업적 광고가 제한 된 병원의 마케팅 전략에 oH우 유용한 것이 훨 수 있다. 또한 불만족한 소비자일수록 발신 자적 입장에 서서 주위의 사람들에게 활발한 구전 활동을 수행하고 었음을 알 수 있다. 이 는 의료 소비자들이 만족한 경우보다는 불만족한 경우에 더욱 구전을 수행하려는 의지가 강해짐올 시사한다. 따라서 병원은 소비자들의 불만을 감소시키기 위해 노력해야 한다. 특히 의료인의 친절함이 가장 많이 구전이 되는 것을 알 수 있었는데 의사나 간호사는 치료 나 간호의 직접적인 제공자로서 의료 소비자들의 만족도에 중요한 영향을 미치므로 의료소 비자들의 요구에 부응하는 서비스를 충족시켜 줄 수 있도록 노력해야하며 이러한 바탕 위에 병원마케팅 전략이 수립되어야 할 것이다.

• The KIPS Transactions:PartC
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• v.8C no.5
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• pp.647-656
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• 2001

Video delivery from a server to a client across a network system is an important part of many multimedia applications. Usually, the network system has constraint in both the amount of network bandwidth and the buffer size in the client. While delivering a video stream across such a constrained network system, loss of frames may be unavoidable. The system resources consumed by the dropped frames are wasted, and the losses of frames would result in discontinuous display at the client. In this paper, for delivering hierarchically encoded video stream, we introduce the notion of selective layer discard algorithm at the server which not only preemptively discards data at the server but also drops less important part of a frame instead of the entire frame. By the simulation, we compare the proposed selective layer discard algorithm and the existing selective frame discard algorithm. The simulation results show that the proposed algorithm may improve the quality of decoded video, and decrease the replay discontinuity at the client.

• The Journal of the Korea Contents Association
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• v.14 no.11
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• pp.355-361
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• 2014

The aim of the present study was to evaluate a relative emission of image plate (IP) in computed radiography (CR) system by using relative sensitivity in film/screen methods. The characteristic curve was obtained by using the uniform aluminum 11-step wedge penetrometer. X-ray exposure factors on radiographic digital image were 50 kVp, 10 mAs. We adjusted zero of all parameter of algorithms (MUSICA) so proximate to raw data and applied to 200 of exposure class. Modeling on relative emission of IP are used IP without fading time and IP after 4 hours, 8 hours, 12 hours, 24 hours in the respective storage after X-ray exposure. The results of this study showed that the sensitivity point density at the measuring of relative sensitivity in CR was suited pixel values of the 2000 easy to relatively measure the characteristic curve and when relative sensitivity is decreased, the amount of light emitted from the image signal for generating was also decreased. In conclusion, the proposed method of measurement of relative sensitivity can be utilized to evaluate the quantity of relative emission of IP in CR system.

• Korean Business Review
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• v.18 no.2
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• pp.21-43
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• 2005

Since China opened its market to foreign investors, overseas Chinese firms have been the biggest foreign investors. Because of the uncertain market environment, other foreign finns incurred larger liabilities of foreignness than overseas Chinese finns. Some parts of liabilities of foreignness stem from cultural differences and last for quite long time. Therefore better understanding of Chinese culture and guanxi network can give overseas Chinese finns competitive advantages over those from other countries by offering market information and reducing transaction costs. Also better management skills, information about export markets and abundant capital allow them to maintain competitive strengths over local firms. As foreign firms accumulate market knowledge in China, they can reduce liabilities of foreignness. However, it is very difficult for foreigners to understand Chinese cultures and to utilize guanxi network as well as Chinese. It is likely that Overseas Chines firms can have competitive strengths in some industries such as banking, retailing, and foreign trade, where relationship with local contractors and exploitation of worldwide Chines networks can play important roles to make successful business deals.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.6
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• pp.47-54
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• 2013

In this paper, analyze the technical elements of the CTI system to design the proposed system, understand the requirements of CTI IP based system. in the Hearing-Impaired designed a CTI system of mobile phone-based services available to the CTI call center system based on this. Furthermore, we implemented voiceXML scenario data analysis modules using the JAVA language to implement the system was designed, the server provides. And an implementation of the CTI system of mobile phone base for the Hearing-Impaired by integrating the modules that have been implemented. Finally, create a scenario that uses the CTI system for mobile base to test and evaluation, based on the test scenario each functional, we conducted repeated tests. It was possible to confirm the results of time for the acquisition of the test result information has been reduced about 20 seconds on average than the audio system based on conventional.