• The Journal of the Korean bone and joint tumor society
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• v.4 no.1
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• pp.65-70
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• 1998

Osteosarcoma is the most common primary bone tumor except for multiple myeloma. Hematogenous spread of osteosarcoma presents the t1susal route of dissemination. Lung metastasis is the most common, however the lymph node involvement is quite rare. In addition, according to Mirra, radiologically detectable involvement of lymph node is an extremely rare manifestation of osteosarcoma. The authors had experienced a patient with an osteosarcoma of the right distal femur which spread to the right inguinal lymph node and lung. After preoperative chemotheraphy, a limb salvage operation was performed around the lesion of right distal femur and the right inguinal lymph nodes were dissected. A adjuvant postoperative chemotheraphy was performed. After the treatment, there was no recurrence of osteosarcoma or any other metastatic evidence for two years and 8 months.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.211-216
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• 2006

Within the frame of the MERCOSUR (South Common Market), one of the most important goals to achieve by its member states is a better cost effective international cargo transportation system. For this purpose the project of developing a commercial waterway linking the east region of Uruguay with the south of Brazil has been under study for a number of years now. Because of the high costs involved on the development of such waterway, the project has been indefinitely delayed. It is our intention to show an alternative way to reduce the present obstacles by using a budget oriented approach in order to determine the vessel best suited to use on the proposed waterway. So far, every study related to the project has been focused on the amount of work needed to modify the environment in order to accommodate the hardware already available in the region. The conclusions show that the cost of opening and maintaining the required navigation channel is high enough to discourage investment; the added responsibility to take care of any environmental damage incurred during the building and/or operation of the waterway makes searching for a less costly and hazardous option an interesting challenge. The proposed terminal on the Cebollat? River would be located at the heart of the Uruguayan rice growing region. Uruguay exports 90% of its rice production, being Brazil its biggest buyer. Wood chips and clinker are the other types of cargo considered to use the proposed waterway in route to either Brazil or to overseas destinations through the deep water port of Rio Grande. Through the analysis of local data by a Geographical Information System, international regulations regarding inland waterways and shallow draught vessel characteristics, we seek to propose a cost efficient alternative to apply on this particular scenario.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.10a
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• pp.274-276
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• 2017

Korean e-Navigation is a system that introduced to reduce maritime accidents. In order to reduce marine accidents, Korean e-Navigation provides the following services-"Vulnerable Vessel Monitoring", "Vulnerable Vessel support & monitoring", "Optimal safety route", "ENC Streaming for Small Vessel", "Tug & Barge Support", "Maritime Safety Information Providing". Each Service is a system separated into finctional units and integrated into Korean e-Navigation. Korean e-Navigation is introducing data middleware to integrate each service and the DDS(Data Distribution Service) is judged to be effective. Thus, this paper analyzed the characteristics of DDS middleware types suitable for each service of e-Navigation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.3
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• pp.491-498
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• 2018

As unmanned aerial vehicle(UVA), drone means a flying object that could aviate the route entered by a program in advance or remotely-controlled when a pilot is not on board. Drone that has been initially developed for the military purpose is currently used for diverse areas such as agricultural industry, leisure activity, logistics service, and life-saving area. Out of these areas, the shooting drone equipped with a camera is actively used for diverse image contents production areas including film and broadcasting area. This paper examines the characteristics of drone for the purpose of shooting, and also handles the shooting techniques using drone. Especially, this study aims to suggest and discuss the methods to shoot diverse camera working used by the existing image shooting with the use of drone after examining the operation of shooting drone used for the image contents production area.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.96-96
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• 2007

Low voltage organic TFTs (OTFTs) and ZnO based TFTs (<5V), utilizing room temperature deposited $Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7$ (BZN) thin films were recently reported, pointing to high-k gate insulators as a promising route for realizing low voltage operating flexible electronics. $Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7$ (BZN) thin film is one of the most promising materials for gate insulator because of its large dielectric constant (~60) at room temperature. However their tendency to suffer from relatively high leakage current at low electric field (>0.3MV/cm) hinder the application of BZN thin films for gate insulator. In order to improve leakage current characteristics of BZN thin film, we mixed 30mol% MgO with 70mol% BZN and their dielectric and electric properties were characterized. We fabricated field-effect transistors with transparent oxide semiconductor ZnO serving as the electron channel and high-k $(Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7)_{0.7}(MgO)_{0.3}$ as the gate insulator. The devices exhibited low operation voltages (<4V) due to high capacitance of the $(Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7)_{0.7}(MgO)_{0.3}$ dielectric.

• International Journal of Highway Engineering
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• v.9 no.3
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• pp.63-74
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• 2007

Traffic information provision plays an important role in increasing the efficiency of network operation and in providing convenience for roadway users. As a typical device for disseminating real-time traffic information for collective general public, VMS is a prevalent device nowadays and it is being expanded. However, the actual monetary value of traffic information is not quantified up to now. The previous studies regarding VMS traffic information are mainly focused on the behavioral aspects of road users such as departure time and route choices under traffic information provision conditions. This paper tried to estimate the monetary value of VMS traffic information using discrete choice theory and logit model through the stated preference study(SP). The methodological framework adopted in this paper can also be used in evaluating the monetary value of other traffic information providers including PDA, CNS, and mobile phone.

• Journal of Korean Neurosurgical Society
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• v.37 no.5
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• pp.340-344
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• 2005

Objective: Posterior lumbar interbody fusion(PLIF), the current leading method of pedicle screw fixation combined with interbody fusion via posterior route, sometimes requires too much destruction of the facet joint than expected especially for the patient with a narrow spine. On the other hand, tranforaminal lumbar interbody fusion(TLIF) technique provides potential advantages over PLIF and can be chosen as a better surgical alternative to more traditional fusion methods in certain surgical conditions. Methods: From October 1999, 99 PLIF and 29 TLIF procedures were done for the patients with spinal stenosis and instability. Radiological data including the interpedicular distance and the size of the pedicles as well as the clinical parameters were collected retrospectively. The degree of resection of the inferior articular process was compared with the interpedicular distance in each patient who received PLIF. Results: No significant differences were found between PLIF and TLIF regarding the operation time, blood loss, duration of hospital stay, or short term postoperative clinical result. There were no complication with TLIF, but PLIF resulted in 9(9.1%) complications. During PLIF procedure, all patients(n=24) except one with the interpedicular distance shorter than 27mm required near complete or complete resection of the inferior articular processes, whereas only 6(31.5%) of 19 patients with the interpedicular distances longer than 30mm required the similar extent of resection. Conclusion: TLIF is better than PLIF in terms of the complication rate. The patient who had narrow interpedicular distance(<27mm) might be better candidate for TLIF.

• Journal of Korea Port Economic Association
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• v.23 no.2
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• pp.41-61
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• 2007

After the joining in the WTO of China, the container throughputs have begun to increase notably and Continuous developments of China ports are influencing operation and policy of Korea ports. At this point Pyeongtaek Dangjin port which has potency as China trading port confronts with turning point of port development as new port. To this, correct need grasping of North China shippers is important strategic element of PyeongTaek Dangjin Port activation. In this study, there is purpose to present Pyeongtaek Port's activation strategy by grasping customer needs executing questionnaire to China local company about Pyeongtaek Dangjin Port. As a research result, Pyeongtaek Dangjin Port possesses high geographical strength but has problems like development delay, tribe of various route, absence of marketing strategy. To solve this problem, this paper proposes expansion of port and logistics physical distribution equipment, improvement of services, foundation of joint logistics center, establishment of marketing organization etc. Namely, it may overcome only new port's limitation though develop to port of cargo creation style that is not simple cargo dependence style port.

• KIPS Transactions on Computer and Communication Systems
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• v.10 no.10
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• pp.269-276
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• 2021

Recently, smart sensors are used in various environments, and the implementation of ad-hoc sensor networks (ASNs) is a hot research topic. Unfortunately, traditional sensor network routing algorithms focus on specific control issues, and they can't be directly applied to the ASN operation. In this paper, we propose a new routing protocol by using the Q-learning technology, Main challenge of proposed approach is to extend the life of ASNs through efficient energy allocation while obtaining the balanced system performance. The proposed method enhances the Q-learning effect by considering various environmental factors. When a transmission fails, node penalty is accumulated to increase the successful communication probability. Especially, each node stores the Q value of the adjacent node in its own Q table. Every time a data transfer is executed, the Q values are updated and accumulated to learn to select the optimal routing route. Simulation results confirm that the proposed method can choose an energy-efficient routing path, and gets an excellent network performance compared with the existing ASN routing protocols.

• Journal of recreation and landscape
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• v.12 no.4
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• pp.59-66
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• 2018

The purpose of the present study was to compare the long-term management objectives, policy objectives, implementation plans, and detailed plans of four provincial parks established in 2013 using various analysis frameworks. Through this, the study aimed to identify the characteristics of the management plan and extract the implementation plan important to each park by analyzing the priorities in the detailed plan. The long-term management objectives of most parks were to maintain recreational functions by utilizing all the resources of the park, rather than merely preserving the ecosystem. From an ecological perspective, information on major plants and legal protection species are included for most parks, and geological and topographic features considered a major resource. For sustainable forests, it is important to induce the dispersion of concentrated use space. Efficient management systems are distinctively differentiated among the parks. For regional revitalization, the management of programs to link provincial parks and their surrounding areas has become most important. From an ecological perspective, priorities differed for the parks according to their ecological characteristics. For sustainable forests, Moaksan Provincial Park prioritized the visitor reservation system related to the overall park, while the other three parks prioritized alleviating the concentrated use of specific areas. From an efficient management perspective, Daedunsan Provincial Park prioritized aspects related to the cableway. Maisan Provincial Park prioritized inducing the linkage between the use of natural and cultural resources, and Seonunsan Provincial Park prioritized establishing an ecological and cultural commentary operating system. For the base-type leisure activity space, Moaksan Provincial Park prioritized the systematic management and operation of the pilgrimage route, Maisan Provincial Park the connection between the Maisan geography and residents' income, and Seonunsan Provincial Park providing a space for ecological education.