• Journal of Korea Water Resources Association
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• v.46 no.4
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• pp.335-343
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• 2013

Multi-purpose dams are regarded to contribute to the Korean society not only positive affects but also negative ones. Especially, negative considerations are usually prevailed around multi-purpose dam sites and their vicinities even though the Government adopted "act on dam construction and assistance, etc. to neighborhood area" in 1989 and has supported many various projects since 1990. Nevertheless, many arguments and controversies about effects of multi-purpose dams and support projects to vicinities" have happened so frequently and sometimes brought a suit against government. These situations imply that support projects are not so sufficient to fulfil peoples' expectations. Therefore, this research figured out the key factors that affected residents' satisfaction about multi-purpose dams and support projects. The results of the research are as follows: 1) 'social necessity of dams', 'rationality of the process in supporting project' and 'appropriateness of supporting project', were statistically significant to 'customer satisfaction'; 2) among these factors, 'rationality of the process in supporting project' was the most related to 'customer satisfaction': 3) 'appropriateness of supporting project', 'social necessity of dams' were also revealed as second third factors that relate to the satisfaction.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.1
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• pp.103-115
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• 1998

Adhesion of composite resin to tooth structure has been of tremendous signgicance in clinical dentistry. Due to the lack of adhesion between composite restorative resins and enamel and dentin, microleakage occurs at the tooth/restoration interface. This may lead to discoloration, secondary caries, marginal breakdown, postoperative sensitivity, and even pulpal pathology. According to extensive use of composite resin, every effort on improving bonding strength and reducing microleakage between a tooth and composite resin has been continued. This study was conducted to determine the difference in microleakage in enamel and dentin treated with air-abrasion, acid etching and combination when restored with composite resin. Class V cavities were prepared on 30 premolars. The specimens were divided into following groups. group 1:air-abrasion+Scotchbond Multi-purpose group 4 :air-abrasion+All-Bond 2 group 2:acid etching+Scotchbond Multi-purpose group 5 :acid etching+All-Bond 2 group 3:combination+Scotchbond Multi-purpose group 6 :combination+All-Bond 2 #combination:air-abrasion + acid etching The specimens were filled with Z-100 after application of Scotchbond Multi-purpose and All-Bond 2. Thermocycling was conducted by alternately dipping the specimens in $5^{\circ}C$ and $55^{\circ}C$ water for 30 seconds 500 times. 1% methylene blue was applied and the specimens were left for 24 hours at $37^{\circ}C$. After washing out the dye, the tooth was sectioned buccolingually along the axis. The sectioned surface was observed with stereoscope for dye penetration. The author has measured the microleakage in teeth prepared with air-abrasion, acid ethching and combination to study the difference in microleakage following different methods of tooth surface treatment and has come to following results. 1. In comparing microleakage between groups, group 1 and 4 showed statistically significant difference from group 2, 3, 5 and 6(p<0.05). There was no significant difference among group 2, 3, 5, 6(p>0.05) nor between group 1 and 4(p>0.05). 2. In comparing microleakage among tooth surface treatment methods, Air-abrasion group showed significantly more microleakage than acid etching group and combination(airabrasion + acid etching) group(p<0.05). Combination(acid etching+air-abrasion)group tended to show lesser microleakage than acid etching group, but this was not statistically significant(p>0.05). 3. In comparing microleakage between bonding agents, there was no statistically significant difference between Scotch bond Multi-purpose and All-Bond 2(p>0.05).

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.6
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• pp.114-121
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• 2008

Multi-path routing has been studied widely in wired networks. Multi-path routing is known to increase end-to-end throughput and provide load balancing in wired networks. However, its advantage is not obvious in wireless multi-hop network because the traffic along the multiple paths may interfere with adjacent paths. In the paper, we introduce a new multi-path routing scheme, Cluster-Based Multi-Path Routing for multi-hop wireless networks. The main idea of the proposed routing scheme is to extend the hop-by-hop multi-path to a cluster-by-cluster multi-path. In cluster network, each cluster can work independently from other clusters and hence reduce interference. The purpose of the proposed scheme is to find a less interfering path for wireless multi-hop networks. We also showed the throughput improvement of the proposed scheme through simulations.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.215-219
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• 2000

In multi-purpose lathe, the design of tilting turret slide system has on important and critical role enhance accuracy of the machining process. Tilting turret unit is traveled by 3-axis slide systems. There is a need to design this part very carefully. In this research, 3-axis sliding system with tilting turret is modeled by considering the element dividing, material proprties, and boundary conditions using MSC/PATRAN. Mode and frequency analysis of each structures such as saddle, careg, and turret are simulated by MSC/MASTRAN, for the purpose of developing the effective design.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.92.5-92
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• 2001

The KOMPSAT-1(Korea Multi-Purpose Satellite-1) is the first multi-purpose satellite funded by Korean government for the purpose of remote sensing and scientific data gathering in KOREA. It has successfully achieved its own mission since Dec. 21, 1999. This paper provides an overview of the KOMPSAT-1 missions and addresses the nominal mission planning and operation flow. This paper also describes the routine operational orbit determination and orbit prediction process using GPS navigation solution data. Meanwhile, some problems due to inexperience of the multiple mission operations during LEOP(Launch & Early Orbit Phase) and early normal mission were investigated. Then, resolutions that include the development of new mission planning tool are addressed. The KOMPSAT-1´s missions become more complicated rather than its Initially designed ones. In order to accomplish ...

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.217-219
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• 1998

Korea Water Resources Corporation (KOWACO) annually supplies about 2 billion Kwh and 7.3 billion $m^3$ with its 10 multi purpose dams and 20 water supply offices. For the proper control and management of the above utilities, sequential control equipment and SCADA/DCS have been operated and maintained. In this paper, 8 control system evaluations for hydropower dam, water supply, electric power and subway projects during 1984-1997 were reviewed and analyzed. The systematic evaluation method has been established in the points of the purpose, method, procedure, evaluation team, evaluation criteria, total evaluation table and the contents of final recommendation report. With keeping in mind the essential points, it is expected for the more effective and fair evaluation of bids.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.5
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• pp.60-70
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• 2001

In multi-purpose lathe, the design of tilting turret slide system has an important and critical role to enhance accuracy of the machining process. Tilting turret unit is traveled by 3-axis slide systems. There is a need to design this part very carefully. In this research, 3-axis sliding system with tilting turret unit is modeled by considering the element dividing, material proprties, and boundary conditions with PATRAN. Normal mode and frequency analysis of each structures such as saddle, cared, and turret are simulated by NASTRAN, for the purpose of developing the effective design. The results of mode analysis and frequency analysis are visualized with PATRAN, and the design method which can solve the resornance problem by eigenvalues and eigenvectors of each axis is developed as well.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.11a
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• pp.474-481
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• 2000

recently out-door stadium have been built not only for athletic sports but also various events and huge concerts and 50% of the roof of multi-purpose stadium have been covered by dome and the tendency of this kind of building type gradually increase, in spite of this kind of building tendency, the appearance of acoustic obstacle is serious and have little solution of this problem in acoustic-prevent building field. The purpose of this study is for analysis of acoustic Properties(SPL, RT60, RASTI) and answering of characteristics of echo through acoustic computer simulation in Seoul world cup stadium in the first instance.

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.609-609
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• 2003

I. Objectives The purpose of this study was to evaluate the effect of adhesive property on microtensile bond strength and to determine the failure mode. II. Materials and Methods Flat occlusal dentin surfaces were prepared using low-speed diamond saw. The dentin was etched with 37% phosphoric acid. The following adhesives were applied to the etched dentin according to manufacturer's directions；Scotchbond Multi-Purpose in group 1, Primer＆Bond NT in group 2, Scotchbond Multi-Purpose followed by Tetric-flow in group 3. After adhesive application, a cylinder of resin-based composite was built up the occlusal surface.(omitted)

• Journal of Sensor Science and Technology
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• v.32 no.3
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• pp.180-186
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• 2023

Test devices can perform various functions, such as research on detection targets, sensors that detect detection targets, combined products containing sensors, and certification for the launch of combined products. However, the scope of use of test devices is limited because they perform only a single role or could only serve a particular purpose in the past. Therefore, studies on test devices that can perform various functions, such as research on detection targets, sensors that detect detection targets, combined products containing sensors, and certification for the release of combined products are necessary. Accordingly, this study proposes a test device that can increase the scope of use in the technical field of electric fires. In addition, we examine various outcomes of the proposed test device.