• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.772-776
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• 2004

This paper proposes an interference avoidance approach for Constraint-Based Routing (CBR) algorithm in the Multi-Protocol Label Switching (MPLS) network. The MPLS network itself has a capability of integrating among any layer-3 protocols and any layer-2 protocols of the OSI model. It is based on the label switching technology, which is fast and flexible switching technique using pre-defined Label Switching Paths (LSPs). The MPLS network is a solution for the Traffic Engineering(TE), Quality of Service (QoS), Virtual Private Network (VPN), and Constraint-Based Routing (CBR) issues. According to the MPLS CBR, routing performance requirements are capability for on-line routing, high network throughput, high network utilization, high network scalability, fast rerouting performance, low percentage of call-setup request blocking, and low calculation complexity. There are many previously proposed algorithms such as minimum hop (MH) algorithm, widest shortest path (WSP) algorithm, and minimum interference routing algorithm (MIRA). The MIRA algorithm is currently seemed to be the best solution for the MPLS routing problem in case of selecting a path with minimum interference level. It achieves lower call-setup request blocking, lower interference level, higher network utilization and higher network throughput. However, it suffers from routing calculation complexity which makes it difficult to real task implementation. In this paper, there are three objectives for routing algorithm design, which are minimizing interference levels with other source-destination node pairs, minimizing resource usage by selecting a minimum hop path first, and reducing calculation complexity. The proposed CBR algorithm is based on power factor calculation of total amount of possible path per link and the residual bandwidth in the network. A path with high power factor should be considered as minimum interference path and should be selected for path setup. With the proposed algorithm, all of the three objectives are attained and the approach of selection of a high power factor path could minimize interference level among all source-destination node pairs. The approach of selection of a shortest path from many equal power factor paths approach could minimize the usage of network resource. Then the network has higher resource reservation for future call-setup request. Moreover, the calculation of possible path per link (or interference level indicator) is run only whenever the network topology has been changed. Hence, this approach could reduce routing calculation complexity. The simulation results show that the proposed algorithm has good performance over high network utilization, low call-setup blocking percentage and low routing computation complexity.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.268-268
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• 2016

Chemical sensors have attracted much attention due to their various applications such as agriculture product, cosmetic and pharmaceutical components and clinical control. A conventional chemical and biological sensor is consists of fluorescent dye, optical light sources, and photodetector to quantify the extent of concentration. Such complicated system leads to rising cost and slow response time. Until now, the most contemporary thin film transistors (TFTs) are used in the field of flat panel display technology for switching device. Some papers have reported that an interesting alternative to flat panel display technology is chemical sensor technology. Recent advances in chemical detection study for using TFTs, benefits from overwhelming progress made in organic thin film transistors (OTFTs) electronic, have been studied alternative to current optical detection system. However numerous problems still remain especially the long-term stability and lack of reliability. On the other hand, the utilization of metal oxide transistor technology in chemical sensors is substantially promising owing to many advantages such as outstanding electrical performance, flexible device, and transparency. The top-gate structure transistor indicated long-term atmosphere stability and reliability because insulator layer is deposited on the top of semiconductor layer, as an effective mechanical and chemical protection. We report on the fabrication of InGaZnO TFTs with silver nanowire as the top gate electrode for the aim of chemical materials detection by monitoring change of electrical properties. We demonstrated that the improved sensitivity characteristics are related to the employment of a unique combination of nano materials. The silver nanowire top-gate InGaZnO TFTs used in this study features the following advantages: i) high sensitivity, ii) long-term stability in atmosphere and buffer solution iii) no necessary additional electrode and iv) simple fabrication process by spray.

• Journal of KIISE:Software and Applications
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• v.36 no.6
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• pp.431-442
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• 2009

The Software Product Line (SPL) engineering is one of the most promising software development paradigms. With Feature-Oriented Reuse Method (FORM), reusable and flexible components can be built to aid the delivery of various software products such as mobile phone and digital TV applications based on commonalities and variabilities identified during Feature modeling. Model Driven Architecture (MDA) is also an emerging technology which supports developing software products to work on different platforms with platform independent models (PIM). Combining advantages of these two approaches is helpful to build a group of software products which share common Features while working on various platforms. As first step to combine FORM with MDA, we extend UML2.0 with profiles by which FORM architectures and parameterized Statecharts can be modeled. Secondly, we provide rules to examine whether Features are allocated at positions of elements of Statecharts consistently between a Feature model and a parameterized Statechart. Some rules are designed to check the consistency between FORM architectures and parameterized Statecharts. A case study on an elevator control system is provided to demonstrate the feasibility of our modeling approach and consistency checking rules.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.12
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• pp.1959-1970
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• 2013

Attempts were made in this paper to compare the practice of protective actions for information of patients' medical treatment between hospital administrators who do not make direct contact with patients and occupational therapists who usually do. The comparison between jobs in charge showed that occupational therapists did not practice much protective actions for information of patients' medical treatment ($3.52{\pm}.809$) compared to hospital administrators ($3.92{\pm}.724$), even though the former had received regular education about protection, management and supervision of patients' medical information more often ($3.17{\pm}1.129$) than the latter ($3.16{\pm}1.037$). In spite of the fact that occupational therapists were exposed frequently to the danger of revealing medical information in the process of their job performance through talks and communications with patients, they displayed relatively little concern for and awareness of keeping information of medical treatment from being leaked by them. It is thus suggested to promote awareness of medical staff to protect medical information by means of flexible educational system for each occupational group, periodical monitoring, continuing public relation, training and quality control for protection of medical information, as well as routine self-examination of such practice.

• Journal of Korean Neurosurgical Society
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• v.29 no.8
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• pp.1126-1135
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• 2000

Objectives : The goal of surgical management of cerebral arteriovenous malformation(AVM) is elimination of the lesion without development of new neurological deficits. To improve the management results of cerebral AVMs in the future, this article discusses about surgical complications of the AVM and their management. Material and Methods : During the past 18 years, 116 patients with cerebral AVMs were managed by surgery. Among these cases, 7 cases died, 7 cases developed new neurological deficits, 11 cases residual AVM and 5 cases intracerebral hematoma(ICH) after surgery. The author analyzes the causes of those complications and investigates the methods to minimized those complications based on the review of the literatures. Results : One stage removal of AVM and ICH in the poor neurological state were performed in 5 of 7 death cases. Subtotal removal of ICH followed by delayed AVM surgery after recovery is regard as one method to improve the outcome of patient with large ICH. Postoperative new neurological deficits developed owing to normal perfusion pressure breakthrough(NPPB) in 3, judgement error in 2, preoperative embolization in 1 and cortical injury in 1 case(s). Proper management of NPPB, accurate anatomical knowledge and physiological monitoring during operation, and well trained skill for embolization are regard as methods to minimize those complications. Residual AVMs after surgery were noticed in 11 cases, in which unintended 6 cases due to inaccurate dissection of peripheral margin of AVM, and intended 3 cases due to massive brain swelling during operation, 1 cases due to diffuse type and 1 case due to multiple type of AVM. Accurate dissection of peripheral margin of AVM and mild hypotension during operation may help to avoid this complication. Postoperative hemorrhage occurred in 3 cases due to rupture of the residual AVM and in 2 cases due to oozing from the AVM bed. Complete resection of AVM, complete control of bleeding points at AVM bed and mild hypotension during early postoperative period are the methods to avoid this complication. Conclusion : A precise but flexible therapeutic strategy and refined skill for endovascular, radiosurgical and microsurgical techniques are required to successful treatment of cerebral AVM. Adequate timing of AVM resection, accurate anatomical knowledge, proper management of NPPB and accurate dissection of peripheral margin of AVM are the key points for avoiding complications of the AVM surgery.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.8
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• pp.639-651
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• 2018

An analytical solution to generate attitude command profile for agile spacecraft is proposed. In realistic environment, obtaining analytical minimum-time optimal solution is very difficult because of following constraints-: 1) actuator saturation, 2) flexible mode excitation, 3) uplink command bandwidth limit. For that reasons, this paper applies two simplifications, an eigen-axis rotation and a finite-jerk approximated profile, to derive the solution in an analytical manner. The resulting attitude profile can be used as a feedforward or reference input to on-board attitude controller, and it can enhance spacecraft agility. Equations of attitude command profile are derived in two general boundary conditions: rest-to-rest maneuver and spin-to-spin maneuver. Simulation results demonstrate that the initial and final boundary conditions, in terms of time, attitude, and angular velocities, are well satisfied with the proposed analytical solution. The derived attitude command generation algorithm may be used to minimize a number of parameters to be uploaded to spacecraft or to automate a sequence of attitude command generation on-board.

• The Korean Journal of Community Living Science
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• v.24 no.3
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• pp.411-427
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• 2013

To investigate the comparison of dietary status and health behaviors according to obesity, 239 male workers were selected and classified as normal (18.5-22.9 27.2%), overweight (23-24.9, 37.7%), and obese (25-29.9, 35.2%) by body mass index ($kg/m^2$). The SAS (ver. 9.2) program was used and verified by the chi-square and f-value methods. Drinking frequency(2-3 times a week) was higher in normal males(45.3%), but not as high as in obese males (48.1%) (p<0.001). Smoking frequency and amount were the highest in overweight males, but not-quit-smoking was high in obese males(51.9%) (p<0.001). Exercise time was longer in normal males(108 minutes) than other groups(69 overweight males, and 82 obese males (p<0.01). Obese groups(73.8%) slept well (p<0.001), but overweight males(44.4%) showed less than 6 hours of sleep (p<0.01). Meal frequency differed by group(two meals a day 67.7% in normal males (p<0.001), no-snack 65.5% in obese males(p<0.001). The frequency of eating-out was once a day in normal males (38.5%), differed in the eating-out time (lunch(45.8%) in normal males, dinner in overweight males(52.1%) and obese males(59.5%) (p<0.01). Korean food (49.3%) was selected, but noodle differed by group(10.2% normal 21.5% obese (p<0.01). Self-perception of body differed from the body's actual condition(p<0.001). For weight control, exercise(56.4%) was practiced more than diet(18.6%). Nutrition knowledge was poor (correct answer rate was 36.7% in normal males, 41.7% in overweight males, and 46.7% in obese males). For eating attitudes, obese males answered more in "flexible to change eating habits", "supplemented when poor eating"(p<0.001), normal responded in "impact on nutrition to health", "try new food for health"(p<0.01). From these results, it is evident that male workers, especially overweight ones, must work to learn more about health and nutrition so as to combat chronic diseases.

• Progress in Medical Physics
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• v.23 no.3
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• pp.169-176
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• 2012

Frameless method in brain radiosurgery has advantages relative to rigid head-frame method in terms of patient friendly and flexible application of multi-fractionation. However, it has also disadvantages and the most negative point is that it cannot control the patient motion during treatment as lowly as the level of the frame-based radiosurgery, which could affect to the treatment accuracy. In the present study, we analyzed the geometric uncertainty of the intra-fraction motion using the actual treatment records of 294-CyberKnife treatments for brain tumors. Based on the analysis, we statistically presented the magnitude of intra-fraction motion in frameless radiosurgy. The result could provide the quantitative information to determine the adequate treatment margins to compensate the intra-fraction movements.

• Journal of Intelligence and Information Systems
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• v.11 no.3
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• pp.25-43
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• 2005

In modern automated container terminals, automated guided vehicle (AGV) systems are considered a viable option for the horizontal tansportation of containers between the stacking yard and the quayside cranes. AGVs in a container terminal move rather freely and do not follow fixed guide paths. For an efficient operation of such AGVs, however, a sophisticated traffic management system is required. Although the flexible routing scheme allows us to find the shortest possible routes for each of the AGVs, it may incur many coincidental encounters and path intersections of the AGVs, leading to collisions or deadlocks. However, the computational cost of perfect prediction and avoidance of deadlocks is prohibitively expensive for a real time application. In this paper, we propose a traffic control method that predicts and avoids some simple, but at the same time the most frequently occurring, cases of deadlocks between two AGVs. More complicated deadlock situations are not predicted ahead of time but detected and resolved after they occur. Our method is computationally cheap and readily applicable to real time applications. The efficiency and effectiveness of our proposed methods have been validated by simulation.

• Journal of the Korean association of regional geographers
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• v.13 no.5
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• pp.563-575
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• 2007

This study aims to investigate a possibility of using topographic information by web mapping in open environments. Web mapping intends to focus on a map analysis and application of the function and geo-visualization. Functions of Web topographic info-map include a spatial analysis, enlargement and minimization, movement, landuse information, user-controling 3 dimension map, landform cross-section analysis, shortest path analysis. The web system adopts SVG(scalable vector graphics), MYSQL, PHP, XML for mapping. SVG has open source policy, so everyone can use it, as well, it is effective on flexible database linkage, cartographic representation. 3D map is intended to represent 3D map by user-controlled sunshine putting pixel opacity by elevation values after making DEM. Landform is designed to show a cross-section analysis and statistics by retrieving height information from database engine with clicking two points on the map. Shortest path analysis within regions uses Dijkstra's algorithm. Near future, resultantly, the area of WebGIS will have to meet more social demands for use-created geo-information and application, so more researches are needed to be web mapping more applicable for users.