• Journal of Institute of Control, Robotics and Systems
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• v.6 no.8
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• pp.638-651
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• 2000

When the bandwidth resources in a packet-switched network are shared among sessions by MAX-MIN flow control each session is required to transmit its data into the network subject to the MAX-MIN fair rate which is solely determined by network loadings. This passive behavior of sessions if fact can cause seri-ous QoS(Quality of Service) degradation particularly for real-time multimedia sessions such as video since the rate allocated by the network can mismatch with what is demanded by each session for its QoS. In order to alleviate this problem we extend the concept of MAX-MIN fair bandwidth allocations as follows: Individual bandwidth demands are guaranteed if the network can accommodate them and only the residual network band-width is shared in the MAX-MIN fair sense. On the other hand if sum of the individual bandwidth demands exceeds the network capacity the shortage of the bandwidth is shared by all the sessions by reducing each bandwidth guarantee by the MAX-MIN fair division of the shortage. we present a novel flow control algorithm to achieve this extended MAX-MIN fairness and show that this algorithm can be implemented by the existing ATM ABR service protocol with minor changes. We not only analyze the steady state asymptotic stability and convergence rate of the algorithm by appealing to control theories but also verify its practical performance through simulations in a variety of network scenarios.

• Journal of the Korea Convergence Society
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• v.6 no.4
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• pp.235-241
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• 2015

As the broadcast, tele communication and media technology develop, the media are divided into various specialities from the internet to the mobile device. An advertising creative in the field, an innovative changes are taking place that had not been in the era of the passed traditional media TV, newspaper, magazine and etc. It's not but the various media's dividing, also the consumers who use the media are evolving in their media behavior from a passive attitude to a positive one. In other words, They consumers receive the advertising messages with positive attitude to researching the message in the searching tool by themselves and participate, act, and diffuse their acknowledgements. In this thesis, as the advertising creative circumstance like this, these varied advertising creative are tried to explained by the three dimension module that is suggested in this thesis.

• Journal of Korean Society of Rural Planning
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• v.18 no.4
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• pp.91-101
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• 2012

The time management and allotments for various activities of daily life is much different by age groups. This study analyzes time allotments of different age groups for various activities of daily life to figure out the change of main activity by aging through 2009 time use survey by National Statistical Office. Especially we focus on time allotments of rural elderly population and intangible factors for life quality of people instead of physical and environmental elements. The results show that there is a large gap of time allotments for paid and unpaid working time of rural and urban elderly population. Whereas the time for leisure of elderly women in rural areas is much shorter than that of urban elderly women and rural elderly men spend more time to provide community services and help to other households. However, the percentage leisure time of rural elderly people for passive activities such as TV, radio, magazine etc. is longer than that of urban elderly people. We hope that our analysis data could be used for developing new policies and project to improve the life quality of rural elderly population.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.4
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• pp.123-132
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• 1990

This paper deals with the influences on the wall movements and earth pressure distribution for strutted diaphragm wall of various design depth ration and pre-displacement at strutted point. The numerical method is adopted for the study. The conclusions derived from the study were summarized as followes: 1. The elasto-plastic depth ratio in the passive region is found to decrease as such parameters as wall stiffness, soil density and penetration depth ratio decrease. 2. Values of maxium bending moments of the walls decrease with the increase of soil density, and the influence to the wall stiffness increases in proportion to the penetration depth. 3. Maximum strut reaction is found to be inversely proportional to the soil density. 4. Pre-displacement at the point of strut installation must be brougt into consideration on account of its active influence to the deflection of wall bodies.

• Smart Structures and Systems
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• v.14 no.5
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• pp.811-830
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• 2014

A numerical study has been carried out to simulate an innovative monitoring procedure to detect and localize damage in reinforced concrete beams retrofitted with carbon fiber reinforced polymer (CFRP) unidirectional laminates. The main novelty of the present simulation is its ability to conduct the electromechanical admittance monitoring technique by considerably compressing the amount of data required for damage detection and localization. A FEM simulation of electromechanical admittance-based sensing technique was employed by applying lead zirconate titanate (PZT) transducers to acquire impedance spectrum signatures. Response surface methodology (RSM) is finally adopted as a tool for solving inverse problems to estimate the location and size of damaged areas from the relationship between damage and electromechanical admittance changes computed at PZT transducer surfaces. This statistical metamodel technique allows polynomial models to be produced without requiring complicated modeling or numerous data sets after the generation of damage, leading to considerably lower cost of creating diagnostic database. Finally, a numerical example is carried out regarding a steel-reinforced concrete (RC) beam model monotonically loaded up to its failure which is also retrofitted by a CFRP laminate to verify the validity of the present metamodeling monitoring technique. The load-carrying capacity of concrete is predicted in the present paper by utilizing an Ottosen-type failure surface in order to better take into account the passive confinement behavior of retrofitted concrete material under the application of FRP laminate.

• Wind and Structures
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• v.26 no.5
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• pp.279-292
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• 2018

Inspired by the energy harvesting eel, a flexible flag behind a D-shape cylinder in a uniform viscous flow was simulated by using the immersed boundary method (IBM) along with low-speed wind tunnel experimentation. The flag in the wake of the cylinder was strongly influenced by the vortices shed from the upstream cylinder under the vortex-vortex and vortex-body interactions. Geometric and flow parameters were optimized for the flexible flag subjected to passive flapping. The influence of length and bending coefficient of the flexible flag, the diameters (D) of the cylinder and the streamwise spacing between the cylinder and the flag, on the energy generation was examined. Constructive and destructive vortex interaction modes, unidirectional and bidirectional bending and the different flapping frequency were found which explained the variations in the energy of the downstream flag. Voltage output and flapping behavior of the flag were also observed experimentally to find a more direct relationship between the bending of the flag and its power generation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.3
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• pp.195-203
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• 2014

We investigated the effect low salt (2 or 4% salt) concentrations jeotgal made from Todarodes pacificus on the learning and memory impairments in scopolamine-induced (2 mg/kg, i.p.) dementia rats. Rats treated with oral BF-7 (200 mg/kg, p.o.) as a positive control and Todarodes pacificus jeotgal had significantly reduced scopolamine-induced memory deficits in the passive avoidance test. The Morris water maze test or treatment with 2% salt jeotgal made from Todarodes pacificus significantly ameliorated the scopolamine-induced memory deficits in the formation of long- and short-term memory. The acetylcholine content and acetylcholinesterase acitivity paralleled the results of the behavior experiment. There were no significant differences in the brain acetylcholine contents of the experimental groups, while the brain acetylcholine content of the group treated with 2% salt Todarodes pacificus jeotgal was higher than that of the control group. The inhibitory effect of 2% salt jeotgal made from Todarodes pacificus on the acetylcholinesterase activity in the brain was lower than that of the control group. These trends were similar to those of the gamma-aminobutyric acid content. We suggest that Todarodes pacificus jeotgal enhances learning memory and cognitive function by regulating cholinergic enzymes.

• Journal of the Korean Solar Energy Society
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• v.23 no.1
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• pp.1-8
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• 2003

Various efforts to combine new high-tech materials with solar system have been progressed nowadays in order to improve the performance of the existing passive solar system. TIM(Transparent Insulation Material) replacing the conventional outer building envelope glazing as well as the wall is good example for this trend. TI integrated wall is a thermal mass wall with a special shaped TIM instead of using typical envelope materials The tested TIM type is a small(diameter 4mm and thickness 50mm) capillary tube of Okalux model and cement brick(density 1500kg/m3). The purpose of this study was to analyze the thermal performance through the actual measurements performed in a test cell. This study was carried out to justify the following issues. 1) the impact of Tl-wall over the temperature variations 2) the impact of mass wall surface absorptance over the transient thermal behavior and 3) the impact of thermal mass wall thickness over the temperature variations. Finally, as results indicated that the peak time of room temperature was shifted about one hour early when absorptance of thermal mass wall changed from 60% to 95% for the 190mm thickness thermal mass wall test case. the temperature difference of both surfaces of thermal mass wall surface showed about $23^{\circ}C$ during a day of March for the 380mm thickness thermal mass wall case. However, the thermal mass wall was over-heated by outside temperature and solar radiation in a day of May the temperature difference of both surfaces of thermal mass wall surface was indicated $10^{\circ}C$ and inside temperature was observed more than average 22C.

• Asian Journal of Innovation and Policy
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• v.9 no.1
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• pp.95-105
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• 2020

Air pollution is a global challenge that not only threatens public health, but also takes away lives. Strategic communication, in other words, public relations, is an essential way of tackling air pollution and managing the risks involved. Engaging global citizens into the public sphere requires the building of a sense of collectivity and duty on achieving clean air. Strategies and policies on an international scale that are based on the theoretical framework (Behavior Procedure Model) and focus on leading citizens into the mature and unified Collectivity during the observance of the 'International Day of Clean Air for blue skies' are crucial. Notably, the Asian continent has inevitably found itself at the crossroad between economic growth and environmental protection, and has even been observed to be pursuing a passive response to air pollution. The key communication strategies are supported by the three goals, which include: expanding existing communities and building a new Collectivity, supporting international solidarity and individual member state activities, and implementing systems and structures. The key goals can be further specified into six strategies. This paper has analyzed global problems and discussed possible communication strategies to increase public engagement for the observation of the 'International Day of Clean Air for blue skies.' It will be the responsibility of all nations to implement the aforementioned strategies and policies as well as promoting global action.

• Research in Community and Public Health Nursing
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• v.30 no.4
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• pp.426-436
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• 2019

Purpose: This study aimed to investigate the association between indoor environmental exposures and behavioral problems in children with allergic diseases. Methods: We used data from 2015 Panel Study of Korean Children (PSKC). The subjects of this study included 825 children aged 7 years with asthma, allergic rhinitis, or atopic dermatitis. The data was analyzed using hierarchical multiple regression. Results: Factors influencing behavioral problems in children with allergic diseases were passive smoking (β=.15, p<.001), painting from 1year after birth until 1 year ago (β=.13, p<.001), using of linoleum as floor materials (β=.09, p<.001), change of wallpaper From 2 years before pregnancy until 1year after birth (β=.08, p<.001), change of wallpaper from 1year after birth until 1 year ago (β=.07, p<.001), keeping hot food or water in plastic container (β=.06, p<.001), remodeling from 1 year after birth until 1year ago (β=.04, p<.001), using of plastic container (β=.03, p<.001), and change of floor materials from 1 year after birth until 1year ago (β=.01, p=.006) which explained about 10% of behavioral problems. Conclusion: This study showed that indoor environmental exposures were associated with behavioral problems in children with allergic diseases. Based on the findings of this study, programs focusing on controlling of indoor environmental exposures may help to prevent and reduce behavioral problems in children with allergic diseases.