• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.6
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• pp.134-142
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• 2012

This paper presents a study of system identification on the tilt response of the L-type retaining wall located at Tanhyun 11th ACE Apartment, Ilsan in order to understand mechanism how the structure behaves in operational conditions and to provide a reference tilt values for assessing structural abnormality. The retaining wall was extraordinarily tall (14m) in urban area so the long-term monitoring system had been installed with 3 tilts-meters and 9 temperature sensors operational from Oct 2004 upto Nov 2007. By using 5-months continuous data in which all the 12 channels were up and running, the two prediction models, 1) the linear model, and 2) the state-space equation (SSE) model, have been identified by finding the best fitness model among all possible 511 combinations of input temperatures out of the 9 temperatures. The linear model which was simple in the model structure achieved the validation fittness of 68% due to the fact that the static model wasn't able to represent thermal dynamics. The SSE model achieved the validation fitness of 90% which was quite accurate considering various unexpected noises happening in field measurements.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.2D
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• pp.137-145
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• 2012

According to the National Police Agency, the total number of traffic accidents which occurred in 2010 was 226,878. Intersection accidents accounts for 44.8%, the largest portion of the entire traffic accidents. An research on the signalized intersection is constantly made, while an research on the unsignalized intersection is yet insufficient. This study selected traffic volume, road width, and sight distance as the input variables which affect unsignalized intersection accidents, and number of accidents as the output variable to build a model using ANFIS(Adaptive Neuro-Fuzzy Inference System). The forecast performance of this model is evaluated by comparing the actual measurement value with the forecasted value. The compatibility is evaluated by R2, the coefficient of determination, along with Mean Absolute Error (MAE) and Mean Square Error (MSE), the indicators which represent the degree of error and distribution. The result shows that the $R^2$ is 0.9817, while MAE and MSE are 0.4773 and 0.3037 respectively, which means that the explanatory power of the model is quite decent. This study is expected to provide the basic data for establishment of safety measure for unsignalized intersection and the improvement of traffic accidents.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.3
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• pp.74-90
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• 2010

The objectives of this paper are to introduce the GIS based resource circulation information, and to identify additional(or potential) industrial symbiosis based on existing industrial symbiosis and linkage-pair of industry by material. The resource circulation information contains information of the reuse of materials, water, and energy for all manufacturing companies in Ulsan Metropolitan City. The information can further be classified into the three steps -- input information(raw materials), flow information (products), and output information (by-products). The survey data from 3,768 industries and institutions in Ulsan Metropolitan area were collected and built into the GIS to analyze the mechanism of the industrial symbiosis. The results of this study strongly suggest that there are some additional industrial symbioses using by-products(materials, steam, waste water) and further efforts should be given to make them more effective. We expect that the methodology of building the resource circulation information of this study can be helpful to other local governments that try to build similar system.

• Journal of the Korean Society for Marine Environment & Energy
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• v.18 no.2
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• pp.102-115
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• 2015

Several emergy researches have been carried out to estimate the value of marine ecosystem services in Korea over the last decade. Their results cannot be compared mainly due to inconsistency in emergy-money ratios used to convert emergy unit into monetary unit. This study aimed at providing a standardized format for the emergy evaluation of the Korean economy and environment for different emergy evaluations to be compatible. Even though the area of the continental shelf increased in this study compared to those of previous studies, areaweighted average tidal range for the entire continental shelf of Korea resulted in smaller tidal range, decreasing the final emergy input from tide. However, emergy inputs from nonrenewable resources and purchased goods and services increased with new categorization and use of more detailed data, combined with updated unit emergy values. This led to higher emergy-money ratio for the Korean economy, indicating that previous emergy valuations might have overestimated the contributions of marine ecosystem to the real wealth of the Korean society. The base year for gross domestic product used in the emergy evaluation needs to be clearly indicated due to its impact on the calculation of the emergy-money ratio. A standardized emergy table for the Korean economy will contribute to ensuring consistency among future emergy researches on the valuation of marine ecosystem services.

• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.32-38
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• 2016

BACKGROUND: Our study aims to investigate the impact of temperature on the abundance and structure of soil microbial community in a temperature gradient tunnel.METHODS AND RESULTS: To investigate the interaction between temperature and input of C and N, rice straw and urea were applied to the study plots, respectively. We also studied the impact of plants by comparing plots cultivated with rice and unplanted plots. Soil microbial response was measured using the phospholipid fatty acid (PLFA) analysis. Soil chemical properties, including pH and ammonia and phosphate concentrations were influenced by warming and material addition. Microbial PLFA was partially influenced by material inputs, and actinomycetes PLFA was decreased by warming. In cultivated rice plots, an increase in the carbon to nitrogen ratio illustrated the effect of plant on microbiota caused by carbon addition through the root residues. Results from the principal component analysis of PLFA data showed that warmed and control plots applied with rice straw could be separated by principal component analysis.CONCLUSION: Our results suggest that plant influence both the microbial community structure and abundance, and temperature change has a minimal impact on soil microorganisms in flooded soil.

• Journal of Korean Society of Transportation
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• v.27 no.4
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• pp.155-166
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• 2009

Road design safety assessment by existing tools and methods have normally been examined by expert judgements using design documents and on-site inspections. The existing methods, however, have two main problems such as insufficiency of objectiveness and inability to measure effects of accident countermeasures. This paper studies ways to develop a road safety assessment system through reviewing the IHSDM developed in USA. The crash prediction module of IHSDM calculate accident frequency and rate of roadway segments using accident prediction models and accident modification factors for safety evaluation. The methodology of evaluation and development of accident modification factors somewhat overcome the problems of the existing methods. In spite of these advantages, IHSDM could not relevantly reflect characteristics of domestic rural roadways since it overestimate the number of accidents and rate of korean rural roadways. Especially, IHSDM may not evaluate or consider land use patterns of Korean roadways, and futhermore, original environment on base conditions used to develop IHSDM may not be different from ours. The user requirements being developed for a road safety assessment system for Korean roadways include enhanced flexibility and diversity of data input-output processes.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.281-281
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• 2009

Although national and regional environmentally friend agriculture (EFA) and food development programmes such as the Life-Food Development Plan (LFDP) have been established in Korea, some policy measures in these programmes seem to be unsuitable for Korean organic farming development. Policy measures tend to support external input purchases of organic fertilizers rather than market development actions such as providing consumer information, research, education, training and statistical data collection. The development of an organic action plan (OAP) for Korea is therefore considered essential for the sustainable future of organic farming in Korea. The purposes of OAP are 1) to define and set the clear goals/targets for the organic sector development, 2) to integrate various organic stakeholders and public institutions in partnership, 3)to focus on specific issues with tailored measures and 4) to integrate and develop different policy measures (Stolze, 2005). Most EU member state countries have developed their own OAPs and each reflects its own priorities with regard to organic sector development. This study compares and contrasts the Welsh, England and EU OAP with the Korean Jeonnam Life-Food Development Plan (LFDP) in order to facilitate the development of the organic food and farming sector in Korea. Early action plan, for example, the first Welsh OAP(1999) focused support on developing the supply of organic products whereas later action plans (e.g. England OAPs in 2002 and 2004 and the second Welsh OAP in 2005) focussed more on developing consumer demands for organic products. The EU OAP (2004) also aims at market support related to consumer demand and then organic farming production for its environmental and other social benefits. OAPs not only provide specific issue-solving tools but also perform a role as providing a focus for organic sector development as a whole. The Korean LFDP provides issue-solving tools but plays no regulatory role such as policy development, harmonizing various policy measures and conflicting factors and providing evaluation tools for further development. A national-level OAP could also facilitate international trade of organic products. To achieve better harmonized and sustainable approaches for the Korean organic industry, National- as well as regional- regulatory policy systems are urgently required in the form of an Organic Action Plan.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.1
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• pp.27-34
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• 2001

To investigate the processes governing the distribution of elements in the tidal flat, thirty-eight sediment samples collected from the Saemangeum tidal flat of the Korean west coast were analyzed for their contents of major (Al, Fe, Mg, Ca, Na, K, Ti) and trace (P, Mn, Ba, Sr, V, Cr, Co, Cu, Ni, Zn, Pb) elements. Most elements showed generally lower contents compared to data published for other tidal flats of Korea, and the effect of anthropogenic input could not be recognized in the sediments. The relative abundance and distribution of most of the elements varied significantly with the grain size of sediments. High contents of Al, Fe, Mg, Ti, P, Mn, V, Co, Cr, Cu, Ni and Zn were found in the finer sediments in the upper tidal flat of the study area, suggesting that tidal sedimentation processes play an important role in controlling the distribution of these elements. However, sediment grain size does not impose any significant effect on the abundance and distribution of Ca, Na, K, Ba, Sr and Pb. It appears that the clastic mineralogy in the coarse-grained fractions is the dominant factor determining the distribution of these elements in the study area.

• Journal of Korean Society on Water Environment
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• v.28 no.6
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• pp.923-932
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• 2012

The purpose of this study was to determine parameters of surface cover materials and evaluation the effects on runoff and sediment reductions with rice straw mat with PAM at watershed scale using the SWAT model. In this study, 1) regression equation of CN for rice straw mat + PAM using SCS curve number method was developed, 2) the USLE P factor, being able to reflect simulation of rice straw mat + PAM in the agricultural field, was estimated for various slope scenarios with VFSMOD-w. Then regression equation for CN and USLE P factor were used as input data in the SWAT model. Assuming rice straw mat + PAM is applied to radish and potato fields, occupying 24% of agricultural fields at the study watershed. Result of direct runoff without rice straw mat + PAM was $65,964,368\;m^3,$ with rice straw mat + PAM, direct runoff was $65,637,336\;m^3$, $327,031.8\;m^3$ reductions compared without it. Also, result of sediment without rice straw mat + PAM was 163,531 ton, with rice straw mat + PAM, sediment was 84,779 ton, 78,752 ton reduction compared without it. This analysis showed that about 48% sediment reductions would be expected with rice straw mat + PAM. As shown in this study, rice straw mat + PAM would be used as an efficient site-specific BMPs to reduce runoff and sediment discharge from field.

• Fire Science and Engineering
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• v.28 no.6
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• pp.52-57
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• 2014

The present study suggests the fundamental method for the prediction time of the fire origin by analyzing the combustion phenomenon of inflammable material in the building structure. The heat release rate (HRR) with time variant is evaluated for the interphone as a inflammable material, which is opted from the fire incidents in the stairwell. the fire dynamics simulator (FDS ver. 6.1) is applied in order to analyze the difference of the smoke inflow time to the downstair from the fire event area with various fire pattern. The results show that the maximum inflow time difference for the case of the interphone made from ABS materials is about 4.93 times with the input conditions of heat flux values and the environment in the FDS for the fixed stairwell which composed of total volume $291.3m^3$, floorage $23.3m^2$ and the height of each floor 2.5 m. This research can be practical information for the application method of simulation scheme with experimental data to the fire Identification.