• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.6
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• pp.1640-1647
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• 1993

The numerical diffusion arising from streamline-to-grid skewness produces a deteriorating effect on the numerical accuracy. The QUICKER scheme to reduce the numerical diffusion requires more computational effort than the HYBRID scheme. This paper deals with the relative computational efficiencies of adopting QUICKER scheme with a coarser grid system and of adopting HYBRID scheme with a denser grid system. Laminar driven cavity flow with Re=400, 1000 is used as a test problem. It is found that QUICKER scheme with a coarser grid system is more efficient than the HYBRID scheme with a denser grid system.

• The KIPS Transactions:PartB
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• v.11B no.6
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• pp.633-644
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• 2004

In this paper, we notice that the original NTSS algorithm can be proposed as the NTSS-3 Level algorithm by the multi-resolution technique. The fast block matching algorithm affects the speed by the patten combination and this paper proposes the block matching algorithm in different levels by multi-resolution technique, quite different from the original NTSS Patten. The block matching algorithm requires the multi-candidate to reduce the occurrence of low-image quality by the local minima problem. The simulation result compared to FS shows search speed 16 times quicker, and the PSNR 0.11-0.12［dB］ gets improved Image quality compared to the original fast block matching algorithm NTSS, and the speed is improved up to 0.1 times for improved image by the search point portion.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.42
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• pp.171-179
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• 1997

Genetic Algorithms face an inherent conflict between exploitation and exploration. Exploitation refers to taking advantage of information already obtained in the search. Exploration show that a pattern in bits coupled with another pattern elsewhere in the string is more effective. In this paper shows that the selection method has a major impact on the balance between exploitation and exploration. A more heavy-handed approach seeks to exploit the available information. If decisions must be made quickly, especially those in real-time trading environments, then quicker convergence through exploitation may be more desirable. Also this paper we present some theoretical and empirical the selection method in genetic algorithms for a GA-hard problem.

• Convergence Security Journal
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• v.2 no.2
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• pp.39-47
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• 2002

To recently with the love-letter and Back Orifice the same Worm-virus, with the Trojan and the Linux-virus back against the new species virus which inside and outside of the country to increase tendency the malignant new species virus which is the possibility of decreasing the damage which is enormous in the object appears and to follow a same network coat large scale PC is being quicker, it disposes spontaneously to respect, applied an artificial intelligence technique the research against the next generation malignant computer virus of new form is demanded. Will reach and to respect it analyzes the digital immunity system of the automatic detection which is quick against the next generation malignant virus which had become unconfirmed and the foreign countries which has an removal function.

• Journal of Korea Multimedia Society
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• v.13 no.5
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• pp.771-779
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• 2010

Sketch-based interface is used more and more in developing animation contents. Particularly, there has been a system where the user's sketch inputs are interpreted and presented as live motions. In this study¸ it is to design an animated flight learning system using sketch-based interface. Most of the flights include movements in three-dimensional space and have unique and complex flight patterns. In other words, the actual flight movements not only include acceleration and deceleration, rising and falling, straight or circular flying, but also may include combinations of two or more movements as they simultaneously occur such as accelerating while falling, or slowing down while rising, and so forth. And, currently existing flight learning animation system cannot present such complex flight patterns to the pilots of aircrafts or to those personnel for air-traffic controllers. Hence, it is to be shown in this study that unit-path sketch animation method can support quicker ways to create animations to present those complex flight movements, and requires lesser inputs compared to the existing frame-based animation method. Also, the flight learning system suggested uses the flight-route realization tasks to reflect complex flight patterns, and therefore creates animations close to real as possible.

• Journal of the Korea Society of Computer and Information
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• v.12 no.5
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• pp.49-56
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• 2007

This paper deals with grid job allocation and grid resource scheduling to provide a stable and quicker job processing service to grid users. In this paper, we proposed a fuzzy logic-based grid job scheduling model for an effective job scheduling in computational grid environment. The fuzzy logic-based grid job scheduling model measures resource efficiency of all grid resources by a fuzzy logic system based on diverse input parameters like CPU speed and network latency and divides resources into several groups by resource efficiency. And, the model allocates jobs to resources of a group with the highest resource efficiency. For performance evaluation, we implemented the fuzzy logic-based grid job scheduling model on the DEVS modeling and simulation environment and measured reduction rates of turnaround time, job loss, and communication messages in comparison with existing job scheduling models such as the random scheduling model and the MCT(Minimum Completion time) model. Experiment results that the proposed model is useful to improve the QoS of the grid job processing service.

• The Transactions of the Korea Information Processing Society
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• v.4 no.1
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• pp.237-245
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• 1997

In this paper, a flow control mechanism is proposed which is based on the priority control between communication path of a node. In this scheme, demanding length of a data queue for any pre-defined, then each node in that path is forced to maintains buffer size under the limit by controlling priority level of the path. The communication path which requires higher bandwidth sets its demanding queue length smaller. By providing relationship between the priority of a path and length of its queue, the high bandwidth requesting path has a better chance to get high bandwidth by defining the smaller demanding queue size. And also, by forcing a path which has high flow rate to maintain small queue size in the path of the communication, the scheme keep the transmission delay of the path small. The size of the demanding queue of a path is regularly adjusted to meet the applications requirement, and the load status of the network during the life time of the communication. The priority control based on the demanding queue size is also provided in the intermediate nodes as well as the end nodes. By that the flow control can provide a quicker result than end to-end flow control, it provides better performance advantage especially for the high speed network.

• Tuberculosis and Respiratory Diseases
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• v.40 no.5
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• pp.468-473
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• 1993

Background: Recent advance in video technology, endoscopic equipments, and surgical techniques have expanded the use of thoracoscopy from diagnosis of the pleural diseases to treatment of the various intrathoracic diseases. Video Assisted Thoracoscopic Surgery(VATS) is a pretty new and fascinating thoracic surgical modality, and so we present our early VATS resuls. Methods: Using Video Thoracoscopic techniques in 30 patients for 10 months from July 1992 to April 1993, we had performed a variety of procedures. These incuded (1) bleb resections in 18 patients (19 cases), (2) mediastinal tumor excision in 4, (3) lung biopsies for parenchymal pulmonary disease in 3, (4) pleural biopasies in 3, (5) pleural tumor excision in 1, (6) and pleuropericardial window in 1. Results: There were no mortality associated with the procedures. We had minor 8 complications; prolonged air leak in 3 patients, prolonged serous drainage in 2, recurrence of pneumothorax in 1, Honer's syndrome in 1, and hoarseness in 1 patient. None of the 30 patients had reverted to the conventional full thoracotomies. Mean postoperative hospital stay of non-complicated pneumothoraces was about 5 days, which was a little shorter than conventional thoracotomy group. Conclusion: Though we had somewhat higher postoperative complication rate due to lack of experiences in the begining, we were able to convince that VATS had benifical value for patients; lesser postoperative pain, shorter hospitalization, quicker recovery time, and cosmetically superior scar. The role of VATS can be expanded to the diagnosis and treatment of various thoracic diseases, even to the cardiovascular diseases, with satisfactory outcome and less postoperative morbidity.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.1
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• pp.101-110
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• 2010

In this study, a prediction model for incident reaction time was developed so that we can cope with the increasing demand for information related to the accident reaction time. For this, the time for dealing with accidents and dependent variables were classified into incident grade, A, B, and C. Then, fifteen independent variables including traffic volume, number of accident-related vehicles and the accidents time zone were utilized. As a result, traffic volume, possibility of including heavy vehicles, and an accident time zone were found as important variables. The results showed that the model has some degree of explanatory power. In addition, when the CHAID Technique was applied, the Answer Tree was constructed based on the variables included in the prediction model for incident reaction time. Using the developed Answer Tree model, accidents firstly were classified into grades A, B, and C. In the secondary classification, they were grouped according to the traffic volume. This study is expected to make a contribution to provide expressway users with quicker and more effective traffic information through the prediction model for incident reaction time and the Answer Tree, when incidents happen on expressway

• Korean Journal of Optics and Photonics
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• v.19 no.5
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• pp.376-380
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• 2008

This paper presents the Projection Moire method using a line scan camera. The high resolution feature of a line scan camera makes it possible to scan an image quickly, thus enabling a much quicker 3D profile. This method uses a high resolution line scan camera making it possible to scan an image at high speed simultaneously measuring the 3D profile of a large FOV. When using a high resolution scan camera, a full FOV is scanned, thus requiring just one movement of a projection grating. As a result, the number of grating movements is reduced drastically. The end result is a faster and more accurate 3D measurement. Moving the grating too quickly causes vibration in the imaging system, which will normally be required to apply a stitching technique when using an area scan camera. However the technique is not required when using a line scan camera. Compared with the previous techniques, it has the advantages of simple hardware without moving mechanical parts - single exposure for obtaining three-dimensional information. A method using a high resolution line scan camera can be used in mass production to measure the bump height of wafers or the bump height of package substrates.