• Journal of Korean Society of Environmental Engineers
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• v.34 no.10
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• pp.709-714
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• 2012

This study accessed the adsorption characteristics of the nine nitrosamine species on coal-based granular activated carbon (GAC). The breakthrough appeared first for NDMA and sequentially for NMOR, NPYR, NMEA, NDPA, NDEA, and NPIP. On the other hand, NDBA and NDPHA were not detected in the treated effluent for the operation period. The maximum adsorption capacity (X/M) for the seven nitrosamine species with apparent breakthrough points ranged from $27.5{\mu}g/g$ (for NDMA) to $671.0{\mu}g/g$ (for NPIP). Carbon usage rate (CUR) for NDMA was 1.07 g/day, 13.4 times higher than that for NPIP (0.08 g/day). The X/M values for the seven nitrosamine species were fitted well with a linear regression ($r^2$ = 0.94) by their octanol-water partitioning coefficient ($K_{ow}$).

• Information Systems Review
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• v.17 no.2
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• pp.49-75
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• 2015

In this study, we propose an ubiquitous computing technology (UCT) based construction management (CM) framework which is composed of processes, information systems, and organizations. For this, we first define 14 promising UCT based CM tasks from 140 candidate tasks using a matrix analysis technique. After defining the 14 tasks, we survey the construction management experts with questionnaire of the importance, improvement possibility, ease of implementation of the tasks. Based on the survey results, we select three high priority tasks: material management, operation management, inspection and measurement management. We conceptually design the framework, that is, processes, information systems, and organizations for the 3 tasks to be more innovative by applying the UCT to the CM tasks. Finally, we apply the proposed framework to some construction fields and estimate the effectiveness of the framework. Estimation results show that the CM tasks can be performed more quickly with less man powers using the UCT-based CM framework.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.5
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• pp.1625-1638
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• 2014

Recently, Low Impact Development (LID) has been emphasized as a critical strategy for improving urban water cycle and adapting to climate change. LID is needed to be incorporated in urban planning and development process for effective implementation in the real world. However, little research has examined the relationship between urban planning and LID in Korea. This study addresses this critical gap by 1) examining whether current urban planning institutional system considers LID or not and 2) assessing the extent to which local comprehensive plans integrate LID in seven large cities. Study results show that a few planning guidelines declaratively mention the need of LID but they don't include specific LID strategies. In addition, we found that 7 local comprehensive plans in the sample received a mean score of 11.71, which represents 19.52% of the total possible points and there are wide variations among cities. These findings indicate that there is still considerable room for improvement of local governments on LID. We propose the revision of planning guideline by incorporating LID principles and non-structural and structural LID technologies.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.3
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• pp.92-100
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• 2015

Unlike most other planning processes, brownfield planning generally requires a high level of technical and legal expertise due to potential site contamination. To successfully engage in inclusionary decision making, an adaptive collaboration strategy for brownfield planning is therefore critical. This study examines how a communicative planning approach can be used to overcome the challenge of enabling experts from different fields to work alongside lay people from the local community to achieve a properly balanced collaboration in brownfield planning. After identifying appropriate indicators for collaboration through a literature review of established communicative planning theory, these indicators are applied to the brownfield planning process, highlighting critical points of collaboration such as site prioritization, assessment, remediation, and redevelopment throughout. The results suggest the critical need for an adaptive model focusing on three aspects: 1. Facilitation of a balanced dialogue between the experts with social, cultural, and design-based knowledge and the ones with scientific and engineering-based knowledge, 2. Preparation of an appropriate tool for risk communication with the lay people, 3. Development of decision support system for the integration of expert-oriented technical data and public opinion-oriented subjective data.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2551-2562
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• 2013

Since 2006, an Intelligent Excavation Robot which automatically performs the earth-work without operator has been developed in Korea. The technologies for automatically recognizing the terrain of work environment and detecting the objects such as obstacles or dump trucks are essential for its work quality and safety. In several countries, terrestrial 3D laser scanner and stereo vision camera have been used to model the local area around workspace of the automated construction equipment. However, these attempts have some problems that require high cost to make the sensor system or long processing time to eliminate the noise from 3D model outcome. The objectives of this study are to analyze the advantages of the existing 3D modeling sensors and to examine the applicability for practical use by using Analytic Hierarchical Process(AHP). In this study, 3D modeling quality and accuracy of modeling sensors were tested at the real earth-work environment.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.4
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• pp.45-56
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• 1985

This study was made to evaluate temperature effects on biological wastewater treatment particularly at the lower temperatures. Cell yield coefficients and other kinetic factors were compared by varying temperature for industrial wastes. Bench scale aeration-only complete mixing activated sludge(CMAS) units were operated at temperatures of $1^{\circ}$, $4^{\circ}$, $7^{\circ}$ and $10^{\circ}C$ with substrate concentrations of 5,000 and 200 mg/l COD. The study results indicate that the cell yields were computed to be 0.5 to 0.6 grams VSS per grams BOD removed, and were not influenced by temperature variations. The synthesis/total energy ratios were computed to be 0.45 to 0.58 and had a tendency to become larger at lower temperatures. The endogenous respiration rates were computed to be 0.07 to 0.08/day, and seemed to be independent of temperature. In addition, very little temperature effects were observed when F/M ratio and substrate concentrations were reduced.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.11 s.353
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• pp.159-167
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• 2006

IEEE 802.11i standard specifies full authentication and preauthentication for secure handoff in 802.11 wireless LAN (WLAN). However, the full authentication is too slow to provide seamless services for handoff users, and preauthentication may fail in highly populated WLAN where it is highly probable that the cache entry of a preauthenticated user is evicted by other users before handoff. In this paper, we propose a fast and secure handoff scheme by reducing authentication and key management delay in the handoff process. When a user handoffs, security context established between the user and the previous access point (AP) is forwarded from the previous AP to the current AP, and the session key is reused before the handoff session terminates. The freshness of session key is maintained by regenerating session keys after handoff session is terminated. The proposed scheme can achieve considerable reduction in handoff delay with providing the same security level as 802.1X authentication by letting an AP authenticate a handoff user before making an robust security network association (RSNA) with it.

• Journal of Digital Convergence
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• v.14 no.10
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• pp.515-520
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• 2016

This study conducted the research about the positive effects of Gynura Procumbens on preventing dermatitis and infectious diseases the contemporary people have. To do it, this study measured the concentration of NF-kB, the extract of Gynura Procumbens. In this regard, cytosol, the extract of Gynura Procumbens, and nucleus went through the separation process. The concentration of major NF-kB among various factors to control inflammation was measured with the use of HDF cell. Regarding RAW264.7 cell, the amounts of NO to play an important role in reacting the skin immune system as the media of neural transmission were analyzed. The outcome about the extracts of Gynura Procumbens injected show that it can be expected that as the NF-kB protein and mRNA band were reduced, Gynura Procumbens would have anti-inflammatory effects that could contribute to preventing dermatitis and diseases. In addition, the extracts of Gynura Procumbens have significantly reduced NO with their concentration increasing. In other words, Gynura Procumbens are considered to regulate dependently the production of NO in the concentration of extracts. Thus there is an expectation that the more intensive research would be conducted to heal dermatitis. And it is deemed that Gynura Procumbens would be used as materials for cosmetics as well as foods that the contemporary people can widely consume if a more careful research about anti-inflammatory effects would be sustained on a human bodies' clinical level.

• Journal of the Korean Society for Railway
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• v.20 no.1
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• pp.76-84
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• 2017

Recently, the 'Ecological Network Restoration Project at Chupungnyeong' has been placed; this project is located at the center of the Baekdu mountain spine, the core of the ecological network of the Korean Peninsula. In the process of industrialization since the early 1900s, this area has been under railroad and road construction; as such, wildlife movements have been interrupted and many cases of road-kill have been found. The investment in railroads has increased because railroads are an environmentally sound means of transportation. Single track railways have been converted to double track electric railways and track reforming projects are underway in order to speed up the current railway system. This study suggests to take land use as a standard for assessing the ecological weaknesses of the domestic geo-spaces that are to be affected by rapid extension of railway lines. The land cover map issued by the Ministry of Environment was overlapped with the Korean Railway Line Map for analysis. The results showed that five items were high in sensitivity: paddy fields, fields, deciduous forests, bare land, and inland waters. It seems to be necessary to set weights for highly sensitive land use types; also, specific evaluation criteria need to be reestablished.

• Journal of the Society of Disaster Information
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• v.16 no.2
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• pp.267-275
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• 2020

Purpose: In this study, GPR exploration equipment, spray vehicles and flow meters, core drill, borehole image processing system(BIPS), 3D cavity imagery equipment, and cavity formatting equipment were used to identify this cavity growth process. Method: A certain amount of water was injected in proportion to the mass of the cavity, and the cavity was observed to expand as the injected water was drained out. The cavity rating change was evaluated by quantitatively evaluating the expansion factors and the speed of growth. Results: According to the results of examining the volume change through injection time - injection flow rate - volume increase for the four experimenters, the volume increase decreased as the injection time increased, and there was no further increase in volume if injected for one hour or so. Conclusion: In addition, the injection test analyzed the volumetric variation to determine whether the cause of the cavity occurrence was the effect of the underground burial in the vicinity of the cavity. Therefore, it was found that the cavity expansion is caused by the repetition of the relaxation soil collapse due to the groundwater flow and the loss of the collapsed soil below the cavity.