• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.113-123
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• 2001

The main purpose of this study was to provide information on attenuation effects in forest tree belt of pine stand and oak stand. The relationships between DBH, tree height, clear length, crown area and number of trees and also between distance from noise origin, landslope etc. were analysed by correlation and multiple regression. The results obtained were as follows : 1. There was no difference between pine stand and oak stand in effecting noise attenuation. 2. The noise pressure was highly correlated with all of seven elements tested and both DBH and distance from noise origin have higher r-values than the others. For the pine stand, it was 0.9133 in DBH and 0.9630 in the distance and for the oak stand, 0.9296 in DBH and 0.9565 in the distance. 3. The optimum regression equation for pine stand and oak stand were made by combination of two variables (DBH and distance). The table of noise attenuation was made by optimum regression equation. In the case of pine stand, the attenuation ratio was 29% at 5m, 31.6~32.6% at 10m, 38.3~39.8% at 20m and 45.2~46.6% at 30m. And case of oak stand, the attenuation ratio was 29% at 5m, 31.6~34.2% at 10m, 38.6~41.4% at 20m and 45~47.2% at 30m. 4. As the noise pressure limit at the Urban housing area according to environmental laws is under 55dB, it is suggested by the table of noise attenuation that the distance, and DBH for the pine and oak stand are over 20m, 400cm and 30-35 trees, respectively.

• Explosives and Blasting
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• v.26 no.1
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• pp.23-37
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• 2008

The Dongdaemoon complex stadium is scheduled to remodelled into an international park, which will be named Design Plaza. The Dongdaemoon baseball field was constructed with Rahmen Structure which comprised beams, slabs and columns. In order to assure for viewing, the stadium was composed unusual structure that the height of the front column and the back column was designed differently. The bleachers was an upper arch form for viewing. The slab was not flat unliked the general infrastructure and tilted in stairway type for viewing. If we had applied the mechanical demolition method, we could have predicted several problems. Firstly, the stand could be unstable when the heavy equipment was to crush the reinforced concrete on the slab. Because the slab was not flat. Secondly, the construction expense and construction duration could be increase when the large equipment was to crush the reinforced concrete on the ground. Because the height of the stand was too high to crush on the ground so it needed to build a filling. Thus, we applied both the mechanical demolition method and explosives demolition method at the design stage. The result of explosives demolition was of complete success in terms of structural movement and controlled blasting noise and vibration. This case study provided a good example for a successful application of explosives demolition in urban areas.

• The Journal of the Acoustical Society of Korea
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• v.39 no.5
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• pp.414-423
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• 2020

In this paper, we propose a Dilated Convolution Gate Linear Unit (DCGLU) to mitigate the lack of sparsity and small receptive field problems caused by the segmentation map extraction process in sound event detection with weak labels. In the advent of deep learning framework, segmentation map extraction approaches have shown improved performance in noisy environments. However, these methods are forced to maintain the size of the feature map to extract the segmentation map as the model would be constructed without a pooling operation. As a result, the performance of these methods is deteriorated with a lack of sparsity and a small receptive field. To mitigate these problems, we utilize GLU to control the flow of information and Dilated Convolutional Neural Networks (DCNNs) to increase the receptive field without additional learning parameters. For the performance evaluation, we employ a URBAN-SED and self-organized bird sound dataset. The relevant experiments show that our proposed DCGLU model outperforms over other baselines. In particular, our method is shown to exhibit robustness against nature sound noises with three Signal to Noise Ratio (SNR) levels (20 dB, 10 dB and 0 dB).

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.5
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• pp.24-30
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• 2009

The Sin-Wol filtration plant was an urban infrastructure and off-limits to the public. It is recreated as a representative experiential theme park in the southwest area. It has not only provided places to relax, but has made a new model of urban park by reusing advantages. The current lack of easy access into the park area almost isolates it like a green island. The neighborhood surrounding the park does not have many physical connections to the park to be able to use it. By connecting the surrounding communities with numerous access points into the park and linking the hiking trails and bike paths, the city's need for open space and recreation would be far better satisfied than before. This would allow for the use of the valuable assets of the existing forest and open space.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.1
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• pp.1-9
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• 2017

In this study, a test-bed system simulated a tunnel and concrete track is tested on cite and invested an allowed limit of multi-layered sound absorbing panel for reducing noise reflected on the concrete track in train tunnel considering the criteria and limitation on the theoretical back ground. The studied results are an effective evaluating system of the sound absorbing coefficient influenced fluid effects depending on the vehicle speed in the urban train tunnel and measuring not only structural behaviors of maximum displacement and acceleration of the panel but also dynamic characteristics of damping ratio and natural frequency.

• Journal of Korean Public Health Nursing
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• v.11 no.2
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• pp.121-130
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• 1997

The community health nursing process is essential in providing community health nursing service to the community. It helps to identify community health problems. to prioritize problems, to provide service. and to evaluate service results. However. it is very rare to find a study which applies the community health nursing process. This study intended to apply the community health nursing process to a urban community. The focus of the study was a community consisting of 533 families in a region of Seoul. The study process was as follows: 1) The data was collected by conducting interviews with community leaders and by collecting surveys from the people of the community. 2) The data was summarized and analyzed. 3) The community nursing diagnosis was identified. 4) The nursing diagnosis was prioritized. 5) The general and specific objectives for service were identified. 6) A specific nursing plan was set up. 7) A detailed evaluation plan was established. Four community nursing diagnoses were identified from the community. 1) The utilization rate of health center was found to be low due to lack of knowledge about the health center and low accessibility. 2) High trafic accident rate due to narrow roads. 3) High prevalence of chronic disease due to inappropriate health behavior. 4) High noise level and foul smell due to inappropriate waste management. Among the four community nursing diagnoses. 'High prevalence of chronic diseases was identified as a priority community nursing problem. The criteria for prioritizing community nursing problems were as follows: number of people involved, fragility of clients. severity of the problem. availability. of resources. concern of the people. readiness of nurses. relevance to the national policy. This study describes the general and specific objectives to solve the high prevalence of chronic health problems. nursing plans. and an evaluation plan.

• Explosives and Blasting
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• v.30 no.1
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• pp.17-28
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• 2012

Building demolitions at urban area make some inconvenience to neighborhood through generating noises, ground vibrations, and dusts. For this reason, various methods to control such environmental impacts have been being designed and practiced. Among the methods, the use of explosive demolition is rapidly increasing because it can minimize the inconveniency as well as decrease the working time and cost. In this respect, the old Sung-Nam city hall, which was a Rahmen structure comprised of beams, slabs and columns, was decided to be demolished by explosive demolition. This paper shows that explosive demolition can be the most suitable way of removing old buildings eco-friendly, safely, and economically by showing the observation results obtained from the actual demolition operation for the Sung-Nam city hall.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.6
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• pp.21-33
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• 2017

The purpose of this study is to find out that it can be provided as a basic data to increase the satisfaction with users in the placement and creation of the Green Buffer Zone. In this study, the research was started on the Green Buffer Zone in Gwanggyo new town, which was rebuilt as the zone to use according to the change of legal installation standard of the zone. The subject of this study is the Green Buffer Zone in Gwanggyo new town, which is expected to be completed in step 4 of 2016. As a result of analysing the location and use characteristics of the Green Buffer Zone, the following conclusions were made. First of all, it is categorized into two categories by Buffering / disaster prevention type and land to use adjustment type. Second, the buffer space of commercial space and housing is satisfying, but in commercial space, there is a need for a cushioning function and housing spaces require improvements in the functioning of the landscape. Third, the function of the Green Buffer Zone resets to cushioning function, disaster prevention function, landscape function, utilization function. and The installation criteria are proposed to environmental pollution, noise abatement, and planting trees, etc. Lastly, the future utilization plan considering the location and use characteristics of the Green Buffer Zone is as follows. In the planning stage, preference is given to the characteristics of use of arranging green facility. It is necessary to manage the planned facilities as much as possible by changing them if necessary. Construction stage, it restrictively reflects landscaping facilities within the Green Buffer Zone function. After stage, This study will prioritize the target areas and select necessary areas and need to make efforts to prevent indiscriminate greenery encroachment.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.3
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• pp.333-339
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• 2015

In this paper, the surface settlement resulted from the shallow TBM tunnelling has been numerically simulated. TBM tunnelling is especially used in urban area to avoid serious vibration and noise caused by explosion in NATM. Surface settlement is one of the most important problems encountered in all tunnelling and critical in urban areas. In this study, face vibration of TBM excavation is considered to estimate surface settlement trend according to TBM extrusion. The dynamic excavation forces are calculated by total torque on the TBM cutterhead in mixed-face of soil and weathered rock condition with shallow depth. A 3-dimensional FDM code is employed to simulate TBM tunnelling and mechanical-dynamic coupling analysis is performed. The 3D numerical analysis results showed that dynamic settlement histories and trend of surface settlement successfully. The maximum settlement occurred at the excavation point located at 2.5D behind the face, and the effect of face vibration on the surface settlement was verified in this study.

• Journal of Environmental Impact Assessment
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• v.21 no.2
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• pp.297-314
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• 2012

This study investigates the stigma effect of unwelcomed facilities on apartment prices through multiple regressions based on hedonic price method. The areas studied are Sang-gye Jugong 7, 9, 10 apartment complexes. The facilities analyzed are the Chang-dong Electric Subway Depot and the Do-bong Driver's License Agency. The factors studied include the environmental variable (the elapsed time since the announcement of the re-location of these facilities), the view commanding, the distance from Chang-dong Depot, the distance from Do-bong Driver's License Test Course, the distance from neighboring facilities (subway stations, schools, parks and so on), the floor and each dwelling's exclusive space. The data used are 2,822 sales which have been collected since January 1, 2006. The facts found are as follows; first, the view commanding and the distance from the unwelcomed facilities are statistically significant. second, the environmental variable, 'days' turns out to have a positive (+) and a negative (-) significant relationship with the dependent variable, 'price', in period II and period IV respectively. This implies that the stigma effect is real. third, there are significant differences in the influence on the apartment prices among the independent variables according to time. fourth, the stigma effect is estimated as 33,686,920 Korean won in the case of the apartments which have the view commanding and 30,311,844 won in the other case before the global economic crisis. This effect seems to decrease to 22,085,078 won after the crisis. These facts suggest that stigma effects could be considered as one of the benefits in the cost-benefit analysis of Chang-dong Depot re-location project to produce somewhat higher NPV or B/C ratio.