• Journal of Korean Society of Environmental Engineers
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• v.38 no.6
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• pp.299-308
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• 2016

Seoul metropolitan has established a vision as 'Healthy water-cycle city' to resolve urban water-environmental deterioration. And it established administrative structure to expand Low Impact Development (LID) facilities to recover aggravated water-cycle and water-environment. Therefore, various LID facilities are constructed and operated, however, benefit analytic plans for systematic valuation are insufficient. In this study, to analyze economic, environmental and social benefits of LID facilities, contents for benefit analysis were selected and categorized as water, energy, air quality and climate changes. As a result of quantification and valuation to the beneficial effects, LID facilities showed the total benefit as 1,191~3,292 won/yr. Characteristics of benefit distribution by analysis contents were various reflecting functional characteristics of each LID facility (Water: 30~90%, Energy: 4~44%, Air quality: <1~2%, Climate change: 5~22%). As a result of Triple Bottom Line analysis, economic benefit showed the greatest portion as 75~90%. As further studies, suggested benefit assessment plans for each LID facility should be applied to inter-connected LID systems on complex-scaled area, and synergy effects by various LID systems would be evaluated such as prevention of heat island and flood disasters.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.5
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• pp.556-563
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• 2007

We carried out a laboratory scale experiment about the characteristics of chemically active species produced in hybrid gas-liquid discharges. The electrode configuration which had high voltage electrode in the gas phase and ground electrode in the liquid was utilized while high voltage electrode has been typically positioned in the liquid in other studies. Our electrode was configured in such a way as to increase the energy efficiency of chemical reactions by creating a higher electrical field strength and a narrower pulse width than the typical electrode configuration. The highest ozone concentration was obtained at 45 kV which was the medium value in operating voltages. The decrease of solution conductivity increased the resistance of liquid phase and the electric field strength through the gas phase, so ozone gene-ration rate was enhanced. The increase of voltage promoted the production rate of hydrogen peroxide by increasing the electric field strength. In a lower voltage, the increase of solution conductivity increased the degradation rate of $H_2O_2$, so the $H_2O_2$ generation rate decreased. On the other hand, the effects of UV radiation, shock waves etc. increased the $H_2O_2$ generation rate as the solution conductivity increased. A higher rate of $H_2O_2$ generation can be achieved by mixing argon to oxygen which generates a stronger and more stable discharges.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.4
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• pp.227-234
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• 2007

The present study attempts to provide basic directions to respond to sea-level rise effectively based on the status of sea-level rise and its impact. The impact of the sea-level rise will be one of the most adverse component among climate change due to global warming. The basic approach to deal with sea level rise requires both mitigation and adaptation. Though the emission reduction can reduce a portion of sea level rise, the rising trend cannot be avoided due to the difficulty of the emission reduction and a strong inertia of the ocean. Therefore an effective corresponding direction has to focus on the development of appropriate adaptation strategies. Because sea level rise problem has scientific uncertainty, the corresponding system has to be designed to deal with the processes of information and awareness, planning and design, implementation, and monitoring and evaluation in continuous and long-term process. The future task to correspond effectively to the issue in Korea includes the improvement of scientific information, the development of adaptative measures, the enhancement of people awareness, the consensus of corresponding necessity, and formation of integrated corresponding system.

• Economic and Environmental Geology
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• v.44 no.3
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• pp.239-246
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• 2011

Groundwater in small islands is used as main water resource but the overuse of groundwater may cause seawater intrusion and temperature decrease in geothermal wells. This study aimed to characterize the hydrogeology of Maeum-ri area in Seokmo Island of Ganghwagun using long-term monitoring at groundwater wells and geothermal wells. In the monitoring period seasonal water level change, consistent drop or increase of water levels are not detected. The groundwater temperature about 10m below ground surface shows year cycle variation having two to five months difference with ambient temperature cycle. The storativity was calculated by tidal method. The storativity estimated by adapting tidal efficiency factor showed some larger values than that by using tidal time lag. The result suggested that the tidal method assuming several assumptions on aquifer condition may produce broad ranges but the calculated ranges at this application are reasonable. The similar shape of groundwater level change and tidal effects was observed at several wells clustered east-south-east direction which may implicate the distribution of vertical fracture system strongly related with groundwater flow channels. The applied methodology and study results will bc valuable to evaluate optimal pumping rate for the preservation of groundwater resources, and to manage geothermal development.

• Economic and Environmental Geology
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• v.41 no.4
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• pp.427-442
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• 2008

Estimation of groundwater recharge is one of the most critical issues in sustainable management of groundwater resources. This study estimated groundwater recharge in the Junggwae-Boeun area in Ulsan City, by using the water balance and hydrogeological characteristics of geology and soil. Evapotranspiration was computed by using the Thornthwaite method, and direct runoff was determined by using the SCS-CN technique. Groundwater recharge was obtained as 266 mm/a (20.6% of the average annual precipitation, 1296 mm/a), with 779 mm/a (60.1%) of evapotranspiration and 119 mm/a (9.2%) of direct runoff. Precipitation and groundwater recharge was highly correlated, comparing with the relationships between precipitation and evapotranspiration, and between precipitation and direct runoff. This fact indicates that groundwater recharge responds more sensitively to precipitation than evapotranspiration and direct runoff do.

• Archives of design research
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• v.18 no.3 s.61
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• pp.209-218
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• 2005

Consciously or not, producers have to make many aesthetic choices in creative process of video production. If there are general acceptable aesthetic principles to make right choice it would be guideline of aesthetic decision to somewhat reduce mistakes and errors in the process. This paper proposes a theoretical approach on establishing the media aesthetic principle of 3D animation camera working, which is the most suitable for animation production context. We describe the Herbert Zettl's applied media aesthetics related directly to the camera, which is about the two-Dimensional field focusing on aspect radio and forces within the screen, three-dimensional field focusing on depth, volume, and four-dimensional field focusing on time and motion. In order to have theoretical approach we made an analysis on comparing a camera working of movie with 3D computer animation's one, and reconstructed these basic principles to be suited for the 3D animation production. When applied media aesthetics of the traditional camera working are applied to the 3D animation production, it could be an efficient guideline for it. Futhermore, if we develop the research for the relationship with various visual languages with the basis of these principles, the theory of creative picture composition method for the 3D animation production will be logically and systematically established.

• Archives of design research
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• v.12 no.2
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• pp.133-144
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• 1999

Considering product as mass of information, it is very critical for designers to have good means of accessing to and organizing information on products. However, designers conventionally depend on their experience, bunch of catalogues, or short visit to some fairs for gathering information on products. There are no systematically organized information for designing new products. If any, those are ones developed by market researchers or engineers who speak fundamentally different language from designers. It is needed to develop the information system through which designer can get insights on the essence of product and communicate information with various persons involved in new product planning. At first, the design information in product planning is discussed and the necessity of development of new design information system is emphasized. Then, product is understood as a composite of various attributes and a set of fundamental attributes of product is defined by surveying and summarizing existing theories of product attributes: namely technological, human, and market attributes. The possibility of new design information system is explored by analyzing various relationships between attributes of different products. Computer program 'DISPP' displays various visual information of product itself, perceptual map, trend slope, profile chart and general information of manufacturer, style, color, price, size. Finally, findings of thesis are concluded and further prospects of the study are proposed.

• Analytical Science and Technology
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• v.17 no.6
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• pp.454-463
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• 2004

The sorption behavior of some metal ions on XAD-16-CTA chelating resin was investigated by batch method. The sorption of chelating resin was highly selective for Hf(IV), Zr(IV) and Th(IV) at pH 3.0 ~ 6.0 and the maximum sorption capacity of Zr(IV) ion was 0.81 mmol/g. It was successfully applied to the separation of several rare metal ions from mixed metal solutions by using CDTA, EDTA, NTA and $NH_4F$ as masking agent. The elution order of metal ions obtained from breakthrough capacity and the overall capacity at pH 4.0 was Zr(IV)>Th(IV)>Hf(IV)>U(VI)>Cu(II)>In(III)>Pb(II). Desorption characteristics for metal ions was investigated with desorption agents such as HCl, $HNO_3$, $HClO_4$. 2 M HCl showed high desorption efficiency. Th(IV) ion can be successfully separated from mixed metal ions by using XAD-16-CTA cheating resin.

• Journal of Broadcast Engineering
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• v.6 no.3
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• pp.246-259
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• 2001

Due to recent rapid deployment of Internet streaming service and digital broadcasting service, the issue of how to efficiently support streaming workload in so called "Internet Home Appliance" receives prime interests from industry as well as academia. The underlying dilemma is that it may not be feasible to put cutting edge CPU, boards, disks and other peripherals into that type of device. The primary reason is its cost. Usually, Internet Home Appliances has its dedicated usage, e.g. Internet Radio, and thus it does not require high-end CPU nor high-end Va subsystem. The same reasoning applies to I/O subsystem. In Internet Home Appliances dedicated to handle compressed moving picture, it is not equipped with high end SCSI disk with fast rotational speed. Thus, it is mandatory to devise elaborate software algorithm to exploit the available hardware resources and maximize the efficiency of the system. This paper presents our experiences in the design and implementation of a new multimedia file system which can efficiently deliver the required disk bandwidth for a periodic I/O workload. We have implemented the file system on the Linux operating system, and examined itsperformance under streaming I/O workload. The results of the study show that the proposed file system exhibits superior performance than the Linux Ext2 file system under streaming I/O workload. The result of this work not only contribute to advance the state f art file system technology for multimedia streaming but also put forth the software which is readily available and can be deployed. deployed.

• Journal of Broadcast Engineering
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• v.17 no.1
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• pp.73-80
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• 2012

Recently, medical equipments are developed and used for diagnosis or studies. In addition, demand of techniques which automatically deal with three dimensional medical images obtained from the medical equipments is growing. One of the techniques is automatic bone segmentation which is expected to enhance the diagnosis efficiency of osteoporosis, fracture, and other bone diseases. Although various researches have been proposed to solve it, they are unable to be used in practice since a size of the medical data is large and there are many low contrast boundaries with other tissues. In this paper, we present a fast and accurate automatic framework for bone segmentation based on multi-resolutions. On a low resolution step, a position of the bone is roughly detected using constrained branch and mincut which find the optimal template from the training set. Then, the segmentation and the registration are iteratively conducted on the multiple resolutions. To evaluate the performance of the proposed method, we make an experiment with femur and tibia from 50 test knee magnetic resonance images using 100 training set. The proposed method outperformed the constrained branch and mincut in aspect of segmentation accuracy and implementation time.