• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.5
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• pp.85-91
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• 2003

TLCD is a good alternative to TMD for control of structures because of its cost efficiency, ease of installation, little maintenance requirement, potential for multiple usage, and ease of re-tuning. In this study, the control performances of TMD and TLCD are evaluated and compared for seismically excited structures. Results show that TLCD is more effective than TMD for interstory drift control while TLCD is as effective as TMD for acceleration control. In special. it is shown that interstory drifts are maximally controlled in lower floors and accelerations are reduced most in upper floors. This indicates that TLCD is an effective controller for earthquake-induced structures in terms of structural safety as well as serviceability.

• Steel and Composite Structures
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• v.20 no.4
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• pp.801-812
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• 2016

In an actual design, none of the structures with shear behaviors will be designed for torsional moments. Any failure or damages to roofs, infills, shear walls, and braces caused by an earthquake, will inevitably result in relocation of center of mass and rigidity of the structure. With these changes, the dynamic characteristics of structure could be changed during an earthquake at any moment. The main objective of this paper is to obtain the relationship between time-varying eccentricity of load and corner lateral displacement. In this study, various methods have been used to determine the structural response for time-varying lateral corner displacement. As will be seen below, some of the structural calculation methods result in a significant deviation from the actual results, although these methods include the interaction effects of modes. Controlling the lateral displacement of structure can be performed in different ways such as, passive dampers, friction dampers, semi-active systems including the MR damper and active Systems. Selecting and locating these control systems is very important to bring the maximum safety with minimum cost into the structure. According to this study will be show the relation between the corner lateral displacements of structure and time-varying eccentricity by different kind of methods during an earthquake. This study will show that the response of the structure at the corners due to an earthquake can be very destructive and because of changing the eccentricity of load, calculating the maximum possible response of system can be carried out by this method. Finally, some kind of systems must be used for controlling these displacements. The results shows that, the CQC, DSC and exact methods is comply each other but the results of Vanmark method is not comfortable for these kind of buildings.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.8
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• pp.1632-1638
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• 2011

Electric cables are one of the most important components in a nuclear power plant since they provide the power needed to operate electrical equipment. Despite their importance, cables typically receive little attention since they are considered passive, long-lived components that have been very reliable over the years when subjected to the environmental conditions for which they were designed. The operating experience reveals that a defect of the insulator or poor construction causes the initial failure of cable. However, the number of cable failures increase with plant aging, and these cable failures are occurring within the plants' 40-year licensed period. These cable failures have resulted in plant transients, shutdown, loss of safety functions or redundancy, entries into limiting conditions for operation, and challenges for plant operators. Therefore, diagnosis of MV cable installed in NPPs has become one of the most urgent issues in recent years. In accordance with PSR, condition maintenance for cables is also continuously required. Recently, HFPD tests have been widely performed to diagnose cable in the transmission and distribution cable system. However, on-line HFPD wasn't used in the NPPs because of the danger of plant shutdown, measurement sensitivity and application problems, etc. In this paper, HFPD measurement with portable device was performed to evaluate the integrity of the 4.16kV & 13.8kV cable lines. The test results show that HFPD is highly attractive to the diagnosis of MV cables in NPP by high detection sensitivity on-site.

• The Transactions of the Korea Information Processing Society
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• v.2 no.1
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• pp.95-105
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• 1995

An appendix to the MAP 3.0 specification notes that there are primary advantages to use of fiber optics : noise immunity, ability to run in difficult electrical environments, safety and high data rates. All of these may be quite useful in various manufacturing environments. In this paper, we study on construction schmes for a fiber-based 802.4 MAP system including the use of both bus and star topologies. We suggest passive star network and FDDI network for manufacturing environment. And then, we propose the FDDI protocol including the use a dual ring topology running at 100 Mbps to physical and datalink layer of MAT specification and analysis it's protocol and topology for abilities in manufacturing environments, We evaluate about applications service, time-critical processing and topology of two models in manufacturing environment.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1238-1243
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• 2009

The susceptibilities of major enterohemorrhagic Escherichia coli (EHEC) strains to antimicrobial agents and the cytotoxicity of these agents were examined using a total of 38 strains of E. coli O26, O111, and O157, which are the major serogroups of EHEC. Among the 38 strains, 35, 36, and 36 were susceptible to amikacin, imipenem, and norfloxacin, respectively. These antimicrobial agents were further examined to determine their cytotoxicity on Vero cells as well as their effect on the release of Shiga toxins along with trimethoprim/sulfamethoxazole. Each of the E. coli O26, O111, and O157 strains containing both the stx1 and stx2 genes were grown in the absence or presence of these agents at 1/4 minimal inhibitory concentration for 6 h, 12 h, and 18 h. At the concentrations used in this study, none of the agents significantly altered cell count compared with the control group. The level of cytotoxicity in the imipenem group was lower at 12 hand 18 h than their respective controls. In contrast, the level of cytotoxicity in cultures treated with trimethoprim/sulfamethoxazole, norfloxacin, and amikacin was increased. The strains were also examined for the release of Shiga toxins 1 and 2 following treatment with the agents, which were measured by the reversed passive latex agglutination (RPLA) method. The RPLA assay showed a suppression of release of Shiga toxin 2 in the strain cultures containing imipenem. These results indicate that imipenem may be a safe and effective agent for inhibition of these bacteria, which has clinical implications for the treatment of EHEC infections.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.2
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• pp.189-194
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• 2007

Recently, as consumer's claim fur car safety is increased, quality inspection method fur welding zone is strengthened. Therefore, from the methods that depend on welding zone bead shape size of seat frame in macrography or passive examination, the quality control by whole recording inspection is required. In this study, the system that is measuring automatically if worker checks welding bead fur quality inspection of seat frame is developed using LabVIEW. If the quality standard for the bead width and length of welding zone is inputted, the system measures automatically whether welding zone is bead length or bead width. Measured data is preserved by points and quality recording of welding zone is stored. The car seat きme welding zone is applied and experimented. The results gave good influence o9 the quality control of work efficiency.

• Korean Journal of Child Studies
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• v.3
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• pp.49-62
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• 1982

This is a study to analyze rural area women's perception and practice of prenatal care, which is the fundamental of the education of children. Further, it was aimed to provide basic data for ideal childbirth, upbringing and household management process. For that object, questionnaires were distributed to women living in Yongdong region to judge the level of general understanding on prenatal care. Research was done from three different aspects; dietary life, emotion control and health management. Percentages were drawn out to see the general tendency. The following results were discovered from data analysis: 1. Most subjects of the survey knew well about prenatal care. They had acquired that knowledge from their parents. Most thought that prenatal care is necessary. They answered that they think prenatal care has more or less effect on the fetus. The first dime they thought about prenatal care was after they found that they were pregnant. 2. The subjects knew well about dietary needs for pregnant women carried out much of what they knew. Intake of sufficiently nutritious food is somewhat difficult, but foods that are regarded as bad were avoided thoroughly. It appears that most women have much concern about what they eat during pregnancy. 3. Most of the subjects understood that the emotional stability is necessary but it wasn't put into practice so well as in dietary life. Especially, attitudes connected with emotional development like, "Look or hear only what is good (for the fetus)" were practised little. Efforts for self-restraint as "Not to hate or pick out others' defects or talk bad about others" were appeared to be great, and it is practised well, too. 4. The subjects were well-informed on health area, but practised little. Behaviors for health improvement as to "Lead a regular daily life for health" or "Not to take a long trop" were practised very faithfully. The results of the survey showed that passive attitudes related to tabooed food, self-abstinence and cautions for bodily safety were prevalent; more positive and progressive disposition missing. That is, full perception and active practices for caloric intake, emotional improvement and physical strength development are needed.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.5
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• pp.58-72
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• 2003

Rooftop greenery has been used as a way to solve urban environmental problems by creating green space in densely populated cities. This study was carried out to suggest more effective designs for roof-garden at hospitals through a post-occupancy evaluation. The roofgarden of Asan Medical Center was evaluated with regards to setting, proximate environmental context, users, and design activity by a multi-method including plan investigations, observations, in-depth interviews and questionnaires. The results are summarized as follows; the users' main activities included resting, walking, and talking. A number of users were observed at shaded spaces sitting on such things as benches, pergolas, and shelters. The satisfaction of the users showed high satisfaction level except in the amount of shade, facilities, and shelter. The variables affecting a overall satisfaction were ‘accessibility’, ‘safety’, ‘quality of surroundings’, and ‘suitability for speculation’. By comparing the design concept with using pattern, designer's intention was not reflected sufficiently in several aspects such as ‘event deck for therapy programs’, ‘grove and path’, and ‘low planters’. This study suggests some design implications; it is necessary to furnish shaded sitting places for passive behaviors and pathways for walking or a light exercise. A wind-break wall with glass windows could widen the users' views in a limited space. Natural shade like tree shade or pergola are more desirable than artificial shades. As for the vertical location of the roofgarden, the middle floor could be better than top area for accessibility. Characteristics of building and users should be considered in detail to provide distinct spaces. Proper technical standards for the greening of artificial ground should be established.

• Journal of Communications and Networks
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• v.11 no.6
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• pp.589-598
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• 2009

In wireless sensor networks, a node that reports information gathered from adjacent assets should relay packets appropriately so that its location context is kept private, and thereby helping ensure the security of the assets that are being monitored. Unfortunately, existing routing methods that counter the local eavesdropping-based tracing deal with a single asset, and most of them suffer from the packet-delivery latency as they prefer to take a separate path of many hops for each packet being sent. In this paper, we propose a routing method, greedy perimeter stateless routing-based source-location privacy with crew size w (GSLP-w), that enhances location privacy of the packet-originating node (i.e., active source) in the presence of multiple assets. GSLP-w is a hybrid method, in which the next-hop node is chosen in one of four modes, namely greedy, random, perimeter, and retreat modes. Random forwarding brings the path diversity, while greedy forwarding refrains from taking an excessively long path and leads to convergence to the destination. Perimeter routing makes detours that avoid the nodes near assets so that they cannot be located by an adversary tracing up the route path. We study the performance of GSLP-w with respect to crew size w (the number of packets being sent per path) and the number of sources. GSLP-w is compared with phantom routing-single path (PR-SP), which is a notable routing method for source-location privacy and our simulation results show that improvements from the point of the ratio of safety period and delivery latency become significant as the number of source nodes increases.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1639-1650
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• 2013

Road pavement management is an important activity that affects to national economy, movement and safety of people, and also demands huge amount of budget. Therefore, its management strategy must be established under objective information. In addition, decision support system that produces the management strategy needs to consider practical benefits from various aspects. Considering these aspects, this paper aimed to develop a customized Korean life cycle cost analysis model estimating various effects on road users and socio-environmental costs based on pavement condition. The suggested LCCA model focused on Korean national highway, and tried to adopt a national guideline recommended by Korean government for securing credibility of estimation results. In the development processes, some of the suggestions that do not fit well in the situations of pavement management field were added, altered, or partially modified. These attempts to develop customized asset management system would be an important step to break away from passive attitudes relying on ready-made software, but also to improve awareness about the social benefits from the better maintenance strategy.