• Journal of Korean Society of Environmental Engineers
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• v.31 no.9
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• pp.765-774
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• 2009

Fiber Dyeing and Finishing facility has been recognized as an important pollution source due to its consumption of large volumes of water and chemicals. Unit mass discharge for the conventional water quality parameters such as flowrate, SS, $BOD_5,\;COD_{Mn},\;COD_{Cr}$, TN, TP were estimated. To represent the respective industries, three companies were carefully selected based on its manufacturing goods, flowrate and location at various unit operations and processes. More than 90% of decrease in unit mass estimation between influent and effluent of BOD was observed. But the values themselves were similar to those of Fiber Manufacturing facility due to the high loadings of organic matter. Biodegradability of influent was almost three times higher than that of effluent. Unit mass discharge estimations of unit process (estimated in this study) based on space, products and raw material were similar to those of composite process (estimated by National Institute of Environmental Research), while big difference was observed in the other factors. Unit mass discharge factors calculated in this study can be used as the reference for the estimation of water pollution loading costs in Nakdong river basin. For the effective water pollution control and management, it is essential to characterize the various types of water quality parameters from the effluents of individual industrial wastewater treatment plants.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.1
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• pp.37-51
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• 2020

Following the Paris Agreement adopted at the end of 2015, global stock-taking has been planned to be carried out on a 5-year basis from 2023, and it is mandatory to report on national GHG inventory and progress toward achieving greenhouse gas reduction targets. To prepare for this, it is important to improve the reliability of estimation of the greenhouse gas emission, identify the characteristics of each greenhouse gas emission source, and manage the amount of emissions. As such, this study compared and analyzed the amount of emissions from the landfill sector using the 2000 GPG, the 2006 IPCC Guidelines, and the 2019 Refinement estimation method. As a result, in comparison to 2016, there were 2,287 Gg CO₂_eq. in scenario 1, 1,870 Gg CO₂_eq. in scenario 2-1, 10,886 Gg CO₂_eq. in scenario 2-2, 10,629 Gg CO₂_eq. in scenario 2-3, and 12,468 Gg CO₂_eq. in scenario 3. Thus, when the 2006 IPCC Guidelines were applied with respect to 2000 GPG, it was revealed that greenhouse gas emissions have increased. Such difference in the emission changes was due to the changes in the calculation method and the emission factor values applied. Therefore, it is urgent to develop national-specific values of the emission factor based on characteristics of greenhouse gas emission in Korea.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.304-311
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• 2010

Korea National Forest Inventory System has been adopting different cluster plot design and new equations to estimate growing stock volumes since 2006. These changes have resulted in volume estimations which show some difference from previous ones. This study is to find out the source of such difference. For this, relevant data was collected from 80 plots of 20 cluster samples according to the cluster plot design applied to 4th and 5th National Forest Inventory. Then growing stock volumes were estimated by using current and previous individual tree volume equations respectively. An investigation was made to detect whether such difference in volume estimates was originated from the changes in cluster plot design or from using different volume equations. T-test results showed that the difference from changes in cluster plot design was negligible. Instead, changes in volume equations had statistically significant effects in volume estimation. Since the volume estimation by the 5th National Forest Inventory would bring overestimation by applying different volume equations, all the volume estimations made prior to 2006 would require necessary modifications for international reporting.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.9
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• pp.926-934
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• 2006

In this study, nitrate uptake rate(NUR) and oxygen uptake rate(OUR) tests were conducted for the assessment of application of Terephtalic acid(TPA) by-product as an alternative external carbon source for sewage treatment plant(STP). With the ASM1 installed in GPS-X the substrate removal characteristic was investigated with simulation by obtained data from NUR and OUR test. As a result, the fraction of RBDCOD(readily biodegradable COD) was mort than 90% and specific denitrification rate was observed about 8.00 mg $NO_3^-$-N/g VSS/hr that was similar to conventional external carbon source. In the next step, sensitivity analysis for heterotrophic biomass in ASM1 was conducted. Optimized parameters of ${\mu}_{max,H}$, $K_s$, ${\eta}_g$, and $b_H$ were 6.60/day, 23.3 mg/L, 0.88, and 0.54/day, respectively. Then, relative mean squared error(RMSE) was reduced to about 40%. Optimized parameters value were well corresponded with the substrate removal characteristics of high maximum and final endogenous specific OUR and high specific NUR.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.78-85
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• 2018

In this study, we investigated the cases where there were many opinions in the judgment of the cause of ignition in the case of 20 cases of frozen warehouse fire that occurred in 2017.The research methodology is the scientific fire survey method prescribed by the NFPA 921 CODE. Scientific fire investigation method is fire investigation method by logical reasoning through hypothesis setting, minimizing errors in judgment of ignition source. On the other hand, unscientific fire investigation methods cause many errors by the intervention of irrational factors such as subjective estimation, reasoning judgment, etc. This eventually leads to the problem of human and material responsibility and academic deterioration. In particular, fire not seen as compared to sighted fire makes more errors in ignition sources in the cause investigation. In this study, we set the hypothesis A and hypothesis B based on the review of the fire investigation report and the field survey on the fire case of the cold storage warehouse front line that occurred at ** city ** Mart in 2017.The set hypothesis was tested by the NFPA 921 code. This analytical method will be constructed by NEW Paradigm as a source of fire that is not seen in the future and a source of ignorant fire.In addition, the experimental data of this study will be used to inform the manufacturer and operator of the refrigeration warehouse and serve as basic data for fire prevention.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.1
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• pp.74-85
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• 2013

Since the underground transportation system is a closed environment, indoor air quality problems may seriously affect many passengers' health. The purpose of this study was to understand $PM_{10}$ characteristics in the underground air environment and further to quantitatively estimate $PM_{10}$ source contributions in a Seoul Metropolitan subway station. The $PM_{10}$ was intensively collected on various filters with $PM_{10}$ aerosol samplers to obtain sufficient samples for its chemical analysis. Sampling was carried out in the M station on the Line-4 from April 21 to 28, July 13 to 21, and October 11 to 19 in the year of 2010 and January 11 to 17 in the year of 2011. The aerosol filter samples were then analyzed for metals, water soluble ions, and carbon components. The 29 chemical species (OC1, OC2, OC3, OC4, CC, PC, EC, Ag, Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Si, Ti, V, Zn, $Cl^-$, $NO_3{^-}$, $SO_4{^{2-}}$, $Na^+$, $NH_4{^+}$, $K^+$, $Mg^{2+}$, $Ca^{2+}$) were analyzed by using ICP-AES, IC, and TOR after proper pretreatments of each sample filter. Based on the chemical information, positive matrix factorization (PMF) model was applied to identify the $PM_{10}$ sources and then six sources such as biomass burning, outdoor, vehicle, soil and road dust, secondary aerosol, ferrous, and brakewear related source were classified. The contributions rate of their sources in tunnel are 4.0%, 5.8%, 1.6%, 17.9%, 13.8% and 56.9% in order.

• The Journal of Engineering Research
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• v.3 no.1
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• pp.65-73
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• 1998

One approach to improved image restoration methods has been the incorporation of additional source information via Gibbs priors that assume a source that is piecewise smooth. A natural Gibbs prior for expressing such constraints is an energy function defined on binary valued line processes as well as source intensities. However, the estimation of both continuous variables and binary variables is known to be a difficult problem. In this work, we consider the application of the deterministic annealing method. Unlike other methods, the deterministic annealing method offers a principled and efficient means of handling the problems associated with mixed continuous and binary variable objectives. The application of the deterministic annealing method results in a sequence of objective functions (defined only on the continuous variables) whose sequence of solutions approaches that of the original mixed variable objective function. The sequence is indexed by a control parameter (the temperature). The energy functions at high temperatures are smooth approximations of the energy functions at lower temperatures. Consequently, it is easier to minimize the energy functions at high temperatures and then track the minimum through the variation of the temperature. This is the essence of a continuation method. We show experimental results, which demonstrate the efficacy of the continuation method applied to a Bayesian restoration model.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.5
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• pp.497-503
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• 2014

Minimally invasive intramedullary nail insertion or plate osteosynthesis has shown good results for the treatment of long bone fractures. However, directly seeing the fracture site is impossible; surgeons can only confirm bone fragments through a fluoroscopic imaging system. The narrow field of view of the equipment causes malalignment of the fracture reduction, and radiation exposure to medical staff is inevitable. This paper suggests two methods to solve these problems: surgical navigation using 3D models reconstructed from computed tomography (CT) images to show the real positions of bone fragments and estimating the rotational angle of proximal bone fragments from 2D fluoroscopic images. The suggested methods were implemented using open-source code or software and evaluated using a model bone. The registration error was about 2 mm with surgical navigation, and the rotation estimation software could discern differences of $2.5^{\circ}$ within a range of $15^{\circ}$ through a comparison with the image of a normal bone.

• Journal of Korean Society on Water Environment
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• v.28 no.3
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• pp.375-383
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• 2012

Soil erosion has been emphasized as serious environmental problem affecting water quality in the receiving waterbodies. Recently, Best Management Practices (BMPs) have been applied at a field to reduce soil erosion and its effectiveness in soil erosion reduction has been monitored with various methods. Although monitoring at fields/watershed outlets would be accurate way for these ends, it is not possible at some fields/watersheds due to various limitations in direct monitoring. Thus modeling has been suggested as an alternative way to evaluate effects of the BMPs. Most models, which have been used in evaluating hydrology and water quality at a watershed, could not reflect rainfall intensity in runoff generation and soil erosion processes. In addition, source codes of these models are not always public for modification/enhancement. Thus, runoff-sediment evaluation system using hourly rainfall data and vegetated filter strip (VFS) evaluation module at field level were developed using open source MapWindow GIS component in this study. This evaluation system was applied to Bangdongri, Chuncheonsi to evaluate its prediction ability and VFS module in this study. The NSE and $R^2$ values for runoff estimation were 0.86 and 0.91, respectively, and measured and simulated sediment yield were 15.2 kg and 16.5 kg indicating this system, developed in this study, can be used to simulate runoff and sediment yield with acceptable accuracies. Nine VFS scenarios were evaluated for effectiveness of soil erosion reduction. Reduction efficiency of the VFS was high when sediment inflow was small. As shown in this study, this evaluation system can be used for evaluation BMPs with local rainfall intensity and variations considered with ease-of-use GIS interface.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.7
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• pp.480-487
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• 2012

The field study was carried out to investigate runoff characteristics of non-point source (NPS) by cultivation activity in river district. Two sites were selected mainly as G region (paddy field, green house), located in Kwangju, Gyeonggi Province, and S region (ordinary field), located in Namyangju, Gyeonggi Province, those belong to Paldang reservoir watershed. The paddy field with water storage capacity showed a slow increase in runoff as rainfall intensity increases. Meanwhile, both green house and ordinary filed revealed a rapid increase. The average BOD runoff concentration of paddy field, green house, and ordinary field was 2.0 mg/L, 2.8 mg/L, 7.9 mg/L, respectively. It indicates that ordinary field shows the highest value in BOD, SS, T-N, and T-P concentration due to the soil loss during rainfall. As a result of runoff load estimation according to the field, a T-N runoff load of paddy field was 1,793.9 kg/year, higher than that of ordinary field. It was estimated that a SS runoff load of ordinary field was 69,704 kg/year and accounts for more than 70% of overall runoff load.