• Journal of Korean Society for Atmospheric Environment
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• v.23 no.3
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• pp.265-276
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• 2007

The primary objective of this study is to investigate the effect of media on the performance of biofilters. Two types of experiments were carried out in this study. The first type of experiment used a biofilter with the media composed of three different packing materials of compost, peatmoss and GAC(granular activated carbon), whereas the second type used a biofilter with the media composed of compost only. It was found from the two experiments that the biofilter composed of compost, peatmoss and GAC showed better performance than the one composed of compost only with the higher toluene removal efficiency, lower pressure drop, and more uniform media moisture content. In particular, no appreciable media compression occurred for the biofilter composed of compost, peatmoss and GAC, whereas significant media compression took place in the biofilter composed of compost only. As suggested by the other researchers, it is likely that GAC may be responsible for the higher toluene removal efficiency in the case of the biofilter composed of mixed media especially for the early stage of biofiltration due to its adsorption capability of toluene of such high concentration as 300 ppm. It was also regarded that GAC may playa major role in maintaining lower media pressure drop in the case of the mixed media than the media with compost only because of its mechanical strength resisting to the compression. Nonetheless, further refined experiments may need to draw more accurate conclusion. The results of the additional test run using the same mixed media showed that the biofilter system using the mixed media can be consistently operated for more than 100 days very stably despite sudden change in operating conditions of temperature and flow rate.

• Annals of Clinical Neurophysiology
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• v.14 no.1
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• pp.20-24
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• 2012

Background: Migraine patients can be sensitive to external or internal stimuli, such as light, noise, or hormonal changes. Using transcranial Doppler ultrasonography (TCD) with breath-holding method, we evaluated the changes of cerebrovascular reactivity (CVR) to hypercapnia in women with migraine without aura between fasting and postprandial period. Methods: Twelve women with migraine without aura and the same number of age and sex-matched healthy controls with no significant history of headache participated in this study. Using TCD examinations, we studied mean flow velocity in middle cerebral artery with better temporal window. Each subject was examined consecutively before and after a standard meal, together with serum glucose level and blood pressure. CVR was evaluated with breath-holding index (BHI). Results: Postprandial-BHI (mean+SD) was significantly higher than fasting-BHI (mean+SD) in patients group but not in controls (in patient group; postprandial-BHI=1.38, fasting-BHI=1.08, in control group; postprandial-BHI=1.25, fasting-BHI=1.18, P=0.021 and 0.239, respectively). After meal, serum glucose level was significantly enhanced but blood pressure was not in both groups. Serum glucose level of patients showed a tendency of mild positive correlation with BHIs (${\gamma}$=0.448, P=0.032). Conclusions: Although exact mechanisms are unclear, cerebrovascular reactivity of some women with migraine without aura may be influenced by prandial state.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.137-147
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• 2013

It is essential to understand the hydraulic characteristics of rivers for increasing flood-control capacity and operating hydraulic structures efficiently. Multi-dimensional models can be the proper measures to obtain the detailed information on the hydraulic characteristics of rivers. But huge amount of data and time-consuming work have been the obstacle for applying multi-dimensional models. In this study, simulation technique with multi-dimensional model(EFDC), coupled with COSFIM and FLDWAV, has been developed and applied to the real river system for verification. Developed technique can offers spatial and grid unit information as well as line and section unit information from 1-D modeling. It is considered that the coupling simulation technique can provide useful hydraulic information for river management and treatment.

• Journal of the Ergonomics Society of Korea
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• v.32 no.2
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• pp.189-198
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• 2013

Objective: This research was carried out to study the menu type design of instrument cluster IVIS(In Vehicle Information System) for efficient navigation under deconcentrated situations. Background: A driver controls the IVIS menu using the rest of cognitive resources while driving a car. Although a driver controls the IVIS using extra cognition resources, his or her distraction can still cause some safety problems while driving. Menu type design of instrument cluster is absolutely important for safe and efficient navigation. Method: Four menu types including paging, flow, icon, and list type were identified through reviewing the existing IVIS of vehicle and the menu structure of cellular phone. Four menu types were evaluated through experiment. The experiment consisted of primary and secondary task, which the primary task was to simulate a driving and the secondary task was to control an IVIS menu prototype. Task performances, menu type preferences, and eye-movement patterns were measured in this experiment. Results: The result shows that icon type was the best design in aspect of task performance and preference. A clue for next menu item provided a positive effect for efficient menu navigation. It was identified that most of subjects gazed the middle-top area of IVIS screen from eye-movement pattern. Conclusion: A basic design of Instrument Cluster IVIS was proposed considering the result of this study in the final. Application: The results of this study can be effectively used in the design of Instrument Cluster IVIS.

• The Journal of Fisheries Business Administration
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• v.37 no.2 s.71
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• pp.33-59
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• 2006

This study describes approaches to fisheries management that restrict access by fishers to an area in some way. When fishery closure is established as a technical conservation measure it is a form of input control as a Korea fisheries management system. There are many compelling reasons why a fisheries manager should seriously consider closed areas and/or time restrictions, either as a complement to other measures or as the primary facet of the Korean fisheries management strategy. Fishery closures have been shown to be effective in many fisheries and are an important tool in the management armoury. In many respects justifications for their use and the process of implementation are likely to be relatively straightforward compared to permanent area closures. From a Korean fisheries management perspective, the benefits that flow from fishery closures are usually less easy to predict than for other management measures. Moreover, even if one accepts that implementation of fisherg clossures will provide higher production levels in adjacent fished areas, the potential benefits may often be in danger of being largely dissipated. If, for example, the fishery remains open access, the increased production is likely to attract new entrants into the fishery, thereby driving it back towards bioeconomic equilibrium. From a Korean wider fisheries conservation perspective, however, fishery closures have important and clearly defensible roles to play and some form of zoning arrangement will often effectively serve conservation values. Given the increasing trend towards the establishment of national networks of fisherg closures, it seems likely that fisheries managers throughout the world will need to ensure that they are familiar with the issues surrounding these approaches. The importance of being explicit about the goals for fishery closures in Korea have been continually emphasised throughout this study. There may, of course, be multiple justifications for the measure, in which case it is important to try and specify them in order of priority.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.4
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• pp.71-80
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• 2005

As local flash flood exceeding planned capacity occurs frequently, localized preparedness and response to flood inundation are increasingly important. Using XP-SWMM model and GIS techniques, this study analyzes inundation areas by local flash flood and develops rainfall standards for evacuation with the case of Sadang-Cheon area, a local stream and its nearby highly populated watershed in the southern part of metropolitan Seoul, Flood inundation areas overflowed from drainage systems are analyzed and mapped by amount of rainfall that is derived from reference levels of stream flow. Rainfall standards for evacuation are comprised of 'watch' (40mm/hr) in preparing for near-future inundation and 'evacuation' (65mm/hr) in responding to realized inundation. The methods suggested by this case study may be applied to other urban areas for sound flood prevention policy measures and thus risk minimization.

• Journal of The Korean Association of Information Education
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• v.24 no.1
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• pp.99-106
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• 2020

In this paper, we analyzed the units related to robot education in the Practical Arts textbooks according to the 2015 revised curriculum. As a result, all textbooks had a common system of introduction, development, and organization, and all of them showed a similar flow. Learning objectives were presented in all textbooks, but no affective goals were presented except cognitive and functional goals. The contents of robot learning suggest the meaning and type of robots, the structure and sensors of robots, and the activities of making robots, but the contents of robot ethics, the production and activities of various robot works, and the use of robots in the problem solving process are not presented. The assembly robot and the infrared sensor are used in common, and it consists of presenting robot production and control training materials in experience activities and arranging units through evaluation, and the A, C, and F textbooks also provide the unit auxiliary data. In the future, it will be necessary to include the contents of robot ethics education centered on the design/manufacturer and user-oriented robot ethics such as the recognition of the limits of robots, the principles of using robots correctly, safety education, personal information and privacy protection.

• Korean Journal of Agricultural Science
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• v.39 no.3
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• pp.421-425
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• 2012

The objective of this study was to improve the detection limit of rapid detection kit for Salmonella Typhimurium by image analysis system. The rapid detection kit was comprised of four elements: sample pad, conjugate pad, nitrocellulose pad and absorbent pad. Gold nanoparticle and Salmonella antibody were used as a tag and a receptor. Salmonella antibody and goat rabbit IgG antibody were used as test and control lines on nitrocellulose membrane. The color intensity of test line began to increase from $10^5CFU/mL$ of Salmonella sample. A multiple linear regression analysis was employed to explain the relationship between predicted and measured number of Salmonella cells. The developed model could successfully predict the cell number of Salmonella with validation against extra-experimental result.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.6
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• pp.699-705
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• 2011

High-maneuver missile is a projectile which demands a strong momentum at short time. To produce a necessary thrust for the flight, the gas of high temperature and pressure is generated through explosive combustion of solid propellant, and a great thrust can be obtained by expanding this high temperature and pressure gas. Although the operating time of a rocket motor is less than a few seconds, a failure of part or ablation near the throat of nozzle may take place during the expansion of high temperature and pressure gas for great thrust. In other words, for the precise control of a missile an exact stress analysis considering both, the thermal stress caused by the heat transfer between combustion gas and wall, and the mechanical stress caused by the pressure change in the flow, should be considered first. In this connection, this study investigated the safety, as a point of view of stress and melting point of the material, of the pre-designed thrust generating structure which is subjected to high temperature and pressure as a function of motor operating time.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5903-5908
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• 2012

Objective: The purpose of this study is to investigate the combined effects of exemestane and aspirin on MCF-7 human breast cancer cells. Methods: Antiproliferative effects of exemestane and aspirin, alone and in combination, on growth of MCF-7 human breast cancer cells were assessed using the MTT assay. Synergistic interaction between the two drugs was evaluated in vitro using the combination index (CI) method. The cell cycle distribution was analyzed by flow cytometry and Western blotting was used to investigate the expression of cyclooxygenase-1, cyclooxygenase-2 and Bcl-2. Results: MTT assays indicated that combination treatment obviously decreased the viability of MCF-7 human breast cancer cells compared to individual drug treatment (CI<1). In addition, the combination of exemestane and aspirin exhibited a synergistic inhibition of cell proliferation, significantly arrested the cell cycle in the $G_0/G_1$ phase and produced a stronger inhibitory effect on COX-1 and Bcl-2 expression than control or individual drug treatment. Conclusion: These results indicate that the combination of exemestane and aspirin might become a useful method to the treatment of hormone-dependent breast cancer. The combination of the two inhibitors significantly increased the response as compared to single agent treatment, suggesting that combination treatment could become a highly effective approach for breast cancer.