• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.5 no.2
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• pp.13-19
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• 2009

As the operating time in nuclear power plants (NPPs) increases, the integrity of nuclear components may be continually degraded due to aging effects of systems, structures and components. Recently, a number of NPPs are being operated beyond their design life to produce more electricity without shutting down. The critical issue in extending a lifetime is to maintain the level of safety during the extended operation period while satisfying the international regulatory standards. Therefore, it is beneficial to build a monitoring system to measure an aging status. In this paper, the Aging Monitor (AM) based on lots of aging database obtained from the operating plants and research results on the aging effects was developed to monitor, manage and evaluate the aging phenomena systematically and effectively in NPPs. The AM for the CANDU is divided into 6 modules: (1) Aging Alarm/Coloring Monitor, (2) Aging Database, (3) Aging Document, (4) Real-time Integrity Monitor, (5) Surveillance and Inspection Management System, and (6) Continued Operation and Periodic Safety Review (PSR) Safety Evaluation. The proposed system is expected to provide the integrity assessment for the major mechanical components of an NPP under concurrent working environments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.5
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• pp.529-538
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• 1992

Recently, image signal processing techniques for HDTV signal have been drastically developed. This kind of skill improvement on signal processing need specific memory device for video signal. in this paper, data latch scheme which implements CMOS flip-flop to hold Information from in-put strobe and new reading method is devised to attain a proper access time suitable for HDTY signal. Compared with conventional write scheme, data latch method has two procedures to complete write operation : bit line write and storage cell write, enabling concurrent I /0 operation at the same address. Also, fast read access is possible through the method similar to static column mode and the separated read word line.

• Journal of Yeungnam Medical Science
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• v.16 no.2
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• pp.376-379
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• 1999

We report our experience with a case of urethrolysis using a transvaginal suprameatal approach without lateral perforation of the urethropelvic ligament. A 43-year-old woman suffered from voiding difficulties such as hesitancy, frequency, urgency, decreased urinary flow, residual urine sensation after Marshall-Marchetti-Krantz operation concurrent with hysterectomy. The results of multidisciplinary work-ups of urethral obstruction such as history, vaginal examination, voiding cystourethrography, urodynamic study, showed that she had urethral obstruction due to a previous operation. Since clean intermittent catheterization and alpha-blocker therapy did not improve her symptoms, suprameatal transvaginal urethrolysis was performed to resolve the symptoms. Postoperative follow-up for 5 months showed that the patient remained free from voiding difficulty in their life. We believe that suprameatal transvaginal urethrolysis is worth attempting for urethral obstruction associated with anti-incontinence surgery.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.7
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• pp.677-682
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• 2007

Concurrent competition for finite resources by multiple parts in flexible manufacturing systems(FMS's) and inappropriate initial marking or net structure of Petri net with share resources results in deadlock. This is an important issue to be addressed in the operation of the systems. Deadlock is a system state so that some working processes can never be finished. Deadlock situation is due to a wrong resource allocation policy. In fact, behind a deadlock problem there is a circular wait situation for a set of resources. Deadlock can disable an entire system and make automated operation impossible. Particularly, an unmanned system cannot recover from such a status and a set of jobs waits indefinitely for never-to-be-released resources. In this paper, we proposed a deadlock prevention method using siphon and trap of Petri net. It is based on potential deadlock which are siphon that eventually became empty. This method prevents the deadlock by the control of transition fire and initial marking in the Petri net. An given example of FMS is shown to illustrate our results with deadlock-free.

• The Transactions of the Korea Information Processing Society
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• v.4 no.3
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• pp.871-879
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• 1997

The comversion of printed maps into computerixed data bases is an enormous rask. Thus the autmaotion of the conversion process is essential. Efficient computer representation of printed maps and line drawings depends on codes assigened to chracaters, symbools, and vestor representation of the graphics. In many cases, maps ard constructed in a number of layers, where each layer is printed in a distinct color, and it represents a subste of the map infromation. In order to properly repressnet road information from color map images, an automatic road extraction algorithm is proposed. Road image is separated from graghics by color segmentation, and then restored by the proposed concurrent conditional dilation operation. The internal and external noise of the road image is eliminated by opening and closing operation. By thining and vectorizing line segments, the desited road information is extracted.

• Journal of Positioning, Navigation, and Timing
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• v.12 no.4
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• pp.379-389
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• 2023

According to the Korea Urban Air Mobility (K-UAM) Concept of Operation (ConOps), the Global Navigation Satellite System (GNSS) is recommended as the primary navigation system and the performance specification will be implemented considering the standard of Performance Based Navigation (PBN). However, by taking into account the characteristics of an urban environment and the concurrent operations of multiple UAM aircraft, the current PBN standards for civil aviation seem difficult to be directly applied to an UAM aircraft. Therefore, by referring to technical documents published in the literature, this paper examines the feasibility of applying the proposed performance requirements to K-UAM, which follows the recommendation of navigation performance requirements for K-UAM. In accordance with the UAM ConOps, the UAM aircraft is anticipated to maintain low altitude during approach and landing phases. Subsequently, the navigation performance degradation could occur in the urban environment, and the primary degradation factor is identified as multipath error. For this reason, to ensure the safety and reliability of the K-UAM aircraft, it is necessary to analyze the degree of performance degradation related to the urban environment and then propose an alternative aid to enhance the navigation performance. To this end, the aim of this paper is to model the multipath effects of the GNSS in an urban environment and to carry out the simulation studies using the real GNSS datasets. Finally, the initial navigation performance requirement is proposed based on the results of the numerical simulation for the K-UAM.

• Journal of the Korea Society of Computer and Information
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• v.12 no.1 s.45
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• pp.269-276
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• 2007

National defense research and development is trying to develop the weapon system to satisfy users' requirements at minimum cost, high quality and the shortest period. Under integrated database computer environments, development processes and tools have been developed to implement system engineering and concurrent engineering systematically. In the aerospace defense weapon system, the fixed wing development department has developed and operated the integrated operation and management information system based on web technology to manage efficiently the technical information generated by the R&D process. When this system was applied to the existing R&D project for the aircraft weapon system, it proved and verified its efficiency. In this paper, we describe the future development plan of an integrated R&D framework and an integrated weapon system database based on the integrated operation and management information system which are able to centrol the technical information of KF-X, UAV(Unmanned Aerial Vehicles) and UCAV(Unmanned Combat Aerial Vehicles) programs. We also describe an interoperability and integration plan with WISEMAN which will be operated soon in our research Institute.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.103-106
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• 2012

A memory access method that data are read with different sequences with writing order is a simple but important procedure in many image compression standards, such as JPEG, MPEG1/2/4, H.264, and HEVC. For real time processing, double buffering is widely used using two block sized buffers, that accesses buffers concurrently with alternative way to read and write. In some cases like a transpose memory in 2D DCT with a simple and regular access order, a single buffering which requires only single block sized buffer can be used. This paper shows that even in complex access orders there is a regularity among updating orders within a finite turns, and suggested an effective implementation method using a single block sized buffer to process concurrent read/write operation with different access orders.

• Journal of the Korean Society of Physical Medicine
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• v.10 no.4
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• pp.15-23
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• 2015

PURPOSE: We aims to promote the development of proprioception measurement using smartphones, goniometers, and laser pointers as compared to the conventional use of electrogoniometer measurement. METHODS: Measurements using an electrogoniometer were previously proved to be reliabile and valid. Among E-university students, 20 who had no fracture, operation history, or inflammatory arthritis were examined. These subjects had not performed regular exercise in the past 3 months. Proprioception measurements were performed using four different measurement tools, three times per day, for test-retest analysis. RESULTS: No notable test-retest differences were noted for any of the measurement methods (P>0.05). With regard to the test-retest reliability for each measurement method, we observed that the readings from both the electrogoniometer and smartphone have high reliability (ICC>0.80), whereas the readings from the laser pointer have moderate reliability (ICC>0.60). When assessing the concurrent validity between electrogoniometers with individual measurements, we did not observe any notable difference between the smartphone and electrogoniometer (P>0.05) and these tools in fact showed high correlation (r>0.60, P<0.05) and a moderate reliability (ICC>0.60). Moreover, there was no notable difference in between electrogoniometers and laser pointers (P<0.05). CONCLUSION: CONCLUSION: The findings of this suggested that proprioception can be measured by using smart-phones, and proved that this method has sufficient credibility. Moreover, we noted that the concurrent validity with smartphones was high in comparison with the conventional electrogoniometer, which also indicates the validity and credibility. Based on these findings, we conclude that the measurement of proprioception by using a smartphone can be widely adopted.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5260-5266
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• 2015

To develop weapon system, Concurrent Spare Parts(CSP) is one of the important somethings in terms of Intergrated Logistics System(ILS). CSP is very important to improve the availability of weapon system, and various research about CSP are performed. However, most of the research does not consider the effects between sub-item's failure and weapon system's multiple function. In other words, if sub-item's failure does not seriously influence weapon system's specific function, the point, not necessarily to replace sub-item, is not considered. Therefore, the method to calculate CSP based on above consideration is written by failure-function matrix in this paper. The study follows the procedure below. First, it's to define the operation and maintenance procedure of weapon system. Second, failure-function matrix is developed. Third, simulation model is desinged by input data. Finally, The quantity of CSP is calculated by simulation and evolution strategy, meta-model. This study suggests new research direction to calculate CSP.