• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.424-425
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• 2007

Anti-Reflection and High-reflection coating on the facet of semiconductor laser diode. To prevent internal feedback from both facets for realizing super luminescent diode and reducing the reflection-induced intensity noise of laser diode. Anti-Reflection coating Film was designed by Macleod Simulator. Coating Materials were decided $Ti_3O_5$ and $SiO_2$. Thickness of Coating layer $Ti_3O_5/SiO_2$ were 105[nm], 165[nm]. In the study Anti-Reflection coating Film was design for Laser diode and deposited by Ion-Assisted Deposition system. Then manufactured thin film measured electrical properties(L-I-V, Se, Resistor) and Optical properties(wavelength FFP). Slop-efficiency and FFP characteristic is 0.302[W/A], $22.3^{\circ}$(Horizontal), $24.4^{\circ}$(Vertical).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.29 no.2
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• pp.132-151
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• 1993

The proposed method in this paper. termed the substructural reanalysis technique, utilizes the computational merits of the component mode synthesis technique and of reanalysis technique for the design sensitivities of the dynamic characteristics of substructurally combined structure. It is shown that the dynamic characteristics of the entire structure can be obtained by synthesizing the substructural eigensolution and the characteristics of the eigensolution for the design variables of the modifiable substructure. In this paper , the characteristics of the eigenvalue problems obtained by this proposed method are compared to exact eigensolution in terms of accuracy and computational efficiency. and the advantage of this proposed method as compared to the direct application of the whole structure and experimental results is demonstrated through examples of numerical calculation for the dynamic characteristics (natural frequencies and mode shapes) of a flexible vibration of thin cylinderical shell with branch shell under 2-end fixed positions, boundary condition. Thin cylinderical shell of overall length 1280mm, external diameter 360mm, thickness 3mm with branch shell is made of mild steel. The load condition for dynamic response in this paper is impulsive load of which magnitude is 10kgf, which have short duration of 0.1 sec. and time interval applied to calculate. $\Delta$T is 1.0$\times$10 super(-4) seconds.

• The KIPS Transactions:PartA
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• v.9A no.3
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• pp.287-294
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• 2002

In this paper we propose a new mechanism for file system using a dynamic bitmap assignment. While traditional file systems rely on a fixed bitmap structures for metadata such as super block, inode, and directory entries, the proposed file system allocates bitmap and allocation area depends on file system features. Our approach gives a solution of the problem that the utilization of the file system depends on the file size in the traditional file systems. We show that the proposed mechanism is superior in the efficiency of disk usage compared to the traditional mechanisms.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.03a
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• pp.329-336
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• 2003

The box system that is composed only of reinforced concrete walls and slabs are adopted on many high-rise apartment buildings recently constructed in Korea. And the framed structure with shear wall core that can effectively resist horizontal forces is frequently adopted for the structural system for high-rise building structures. In these structures, a shear wall may have one or more openings for functional reasons. It is necessary to use subdivided finite elements for accurate analysis of the shear wall with openings. But it would take significant amount of computational time and memory if the entire building structure is subdivided into a finer mesh. An efficient analysis method that can be used regardless of the number, size and location of openings is proposed in this study. The analysis method uses super element, substructure, matrix condensation technique and fictitious beam technique. Three-dimensional analyses of the box system and the framed structure with shear wall core having various types of openings were peformed to verify the efficiency of the proposed method. It was confirmed that the proposed method have outstanding accuracy with drastically reduced time and computer memory from the analyses of example structures.

• Computers and Concrete
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• v.24 no.2
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• pp.137-150
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• 2019

In this paper, surrogate models such as multivariate adaptive regression splines (MARS) and M5P model tree (M5P MT) methods have been investigated in order to propose a new formulation for the 28-days compressive strength of self-compacting concrete (SCC) incorporating metakaolin as a supplementary cementitious materials. A database comprising experimental data has been assembled from several published papers in the literature and the data have been used for training and testing. In particular, the data are arranged in a format of seven input parameters covering contents of cement, coarse aggregate to fine aggregate ratio, water, metakaolin, super plasticizer, largest maximum size and binder as well as one output parameter, which is the 28-days compressive strength. The efficiency of the proposed techniques has been demonstrated by means of certain statistical criteria. The findings have been compared to experimental results and their comparisons shows that the MARS and M5P MT approaches predict the compressive strength of SCC incorporating metakaolin with great precision. The performed sensitivity analysis to assign effective parameters on 28-days compressive strength indicates that cementitious binder content is the most effective variable in the mixture.

• Journal of Preventive Veterinary Medicine
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• v.42 no.4
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• pp.182-185
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• 2018

This study examined the overdose toxicity of Super-Neophensan, containing florfenicol and acetaminophen, upon pigs. SNP-3.0 (n=10) was administered at the dosage level of 3 kg/ton feed for 7 consecutive days, which is 3 times the recommended dose based on the guidelines of the manufacturer, and the control group (CON) (n=10) was administered the normal diet without the drug. The body weight, weight gain and feed efficiency in SNP-3.0 treated with the drug for 14 days post-administration showed no significant differences compared with those in CON. In hematological and blood biochemical analyses, all parameters were not affected by over-dosage of the drug. In the same way, there were no significant differences between SNP-3.0 and CON on markers for liver and kidney functions. As no adverse effects were observed with the drug in an overdose oral toxicity test, this study suggests that the drug was identified as a safe agent in pigs administered with three times the recommended dose.

• Journal of Information Technology Applications and Management
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• v.28 no.3
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• pp.23-30
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• 2021

Korea currently provides long-term care benefits for the elderly with poor functionality, but most of the service providers are private businesses. This is the time when quality management of care services is required, which is just around the corner of the super-aged era. In this study, we would like to look at the case in which 'A company', which operates a long-term care institution, attempted to make voluntary changes ahead of social demands. The company tried to transform the social needs of quality management by judging them as opportunities, not threats, and establishing an integrated database of centers. First, the company processed data and built a cloud-based database system. Second, the company automatically linked data from existing systems for the efficiency of data utilization. Third, the company pursued visualization for the convenience of data utilization. This allowed the company to make data-driven strategic decisions internally. This is expected to increase sales as it will soon lead to securing new customers and pioneering new markets. It is also significant in that it can provide best practices for the long-term care industry.

• Journal of Drive and Control
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• v.21 no.1
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• pp.16-21
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• 2024

The yaw gearbox is a key device in a wind power generator that improves power generation efficiency by rotating hundreds of tons (400 to 600 tons) of nacelle so that the blade reaches 90 degrees in the wind direction. Recently, installation sites have been advancing from land to sea as they have become super-large at (8-12) MW to increase the economic feasibility of wind power generators and utilize excellent wind resources, and the target life of large wind power generators is 25 to 30 years. The yaw gearbox of 6 to 12 sets is installed in a very complex place inside the nacelle on the tower with parallels, and it is important to secure the reliability of the yaw gearbox because if a failure occurs after installation, it costs tens to hundreds of times the price of a new product to restore. In this study, equivalent loads were calculated by analyzing failure mode and field data, accelerated life test conditions were established, and a test device was constructed to perform the accelerated life tests and performance tests to ensure the reliability of the gearbox.

• Journal of Korea Port Economic Association
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• v.27 no.4
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• pp.187-205
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• 2011

In considering the size of container logistic flow of Korea, one-port as a hub port is desirable in Busan Port, but as development of Busan Port and Gwangyang Port began as two-ports, they are good as mega hub ports. In case when ports of other regions such as Incheon Port are additionally developed, it is very likely that they become feeder ports rather than mega hub ports. As capital area uses Incheon Port and Pyeongtaek Port for transportation, fierce competition arises due to excessive facilities of terminal companies and it is not easy to be profitable. Therefore, it is more profitable to develop regional hub ports centering on near-sea routes of Korea China Japan rather than local ports such as Incheon Port and Pyeongtaek Port for intensive trade and transportation in the capital area. To mitigate excessive competition between container terminal companies, we need administrative guidance to maintain adequacy through comparing tariffs between ports of Japan and China which are in competitive relations with Korean ports. This study analysed efficiency of container terminal companies in Gwangyang Port, Busan Port and Incheon Port using data for five years from 2006 to 2010. As analytical variables, length of quay, floor area of yard, the number of cranes and employees were analytical variables and a total freight volume was a productive factor.

• Journal of the Korea Society of Computer and Information
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• v.28 no.10
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• pp.247-256
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• 2023

This study was conducted with the purpose of suggesting alternatives for the efficient operation of senior day care facilities in 22 cities and counties in the Jeonnam region by analyzing the efficiency of senior day care facilities. The analysis data for the study used the National Health Insurance Corporation's long-term care insurance for the elderly (2022), the Input variables were the number of facilities, the number of workers, the number of affordable, and the number of senior long-term care insurance recipients and the Output variables were the the number of users. As a result of the analysis, CCR was most efficient in Goheung-gun, Gokseong-gun, Gwangyang-si, Boseong-gun, Yeongam-gun, and Jindo-gun, BCC was most efficient in Goheung-gun, Gokseong-gun, Gwangyang-si, Gurye-gun, Damyang-gun, Boseong-gun, and Jindo-gun, and SE was most efficient in that order: Jindo-gun, Gokseong-gun, and Gwangyang-si. It turned out to be a super efficient area. In the contribution analysis, the number of affordable and workers variables were found to be variables that had a large impact on efficiency contribution. In the improvement potential analysis, the number of facilities variable was found to be a variable that had a significant impact on efficiency. Therefore, for the efficient operation of senior day care facilities, we suggest adjusting supply and demand, such as the number of facilities and affordable, and suggest that training programs to strengthen the expertise of workers who contribute greatly are required.