• Environmental Analysis Health and Toxicology
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• v.25 no.2
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• pp.169-177
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• 2010

Ecological risk assessment (ERA) has been used to establish environmental quality standards or evaluate ecological risk in site-specific areas. The scope of ERA was expanded based on regions, and the concept of regional-scale ecological risk assessment was recently introduced in developed countries. In the present study, regional ERA approaches of relative risk model (RRM), contaminants in aquatic and terrestrial ecosystems (CATS) model, and procedure for ecological tired assessment of risks (PETAR) in advanced countries were extensively investigated. Regional ERA was compared with traditional ERA process. Stressors, receptor and response in traditional ERA were replaced with sources of stressors, habitats, and ecological impacts, respectively in regional ERA. This study introduces the concept and assessment process of regional ERA, and provides a wide perspective how the relative ERA could be applied in Korean ecosystem.

• Journal of the Korean Society of Safety
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• v.16 no.4
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• pp.134-139
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• 2001

The Risk assessment regulation(RAR) is one of the essential articles of the Occupational safety and health law for the construction industry along with safety and health management expense and safety organization regulation. However, arguments regarding the working time of the safety assessment documents, the person in charge of documentation, weakness in legislative enforcement etc. are ongoing. Thus this study aims to analyze the effectiveness of RAR for the guidance of enhancing the effectiveness of RAR. The findings are; 1) the effectiveness of RAR is recognized, however the indirect effectiveness ie, enforcement of safety activities, previewing of drawings etc. are bigger than the direct effectiveness of accident prevention, 2) to enhance the effectiveness of RAR site inspection procedure has to be utilized, 3) further research for identifying and getting rid of negative factors in RAR is recommended.

• Journal of Korea Soil Environment Society
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• v.2 no.3
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• pp.81-88
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• 1997

The purpose of this study is to assess contaminant transfer and environmental impacts to the surroundings by inadequate control of USTs. Several methodologies can be used in sampling procedure for the site assessment depending on the appearance of contaminants on the site and their types. In this case study because of site contaminants, randomized and/or triangle matrix techniques were used. As a result, the composition of materials in OO gas station were appeared in several status. From 1 to 2.5m depth, the soil was composed of silty sand and gravel, around 4m depth, weathered rock was appeared. Based on the preliminary and actual site investigation by DPT methodologies on the width and depth of the site with analysis of BTEX and TPH, no contamination was found in OO gas station, however, in one point because of careless dumping after refill by oil company, about 1731. 5 ppm of TPH appeared.

• Journal of Environmental Impact Assessment
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• v.31 no.4
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• pp.250-264
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• 2022

The development projects subject to health impact assessment (HIA) in the current environmental impact assessment (EIA) system are limited to some projects under Article 12 of the Enforcement Decree of the Environmental Health Act (Additional Assessment Objects Subject to Health Impact Assessment Items), but health impact-related matters are being evaluated and reviewed during consultation. In particular, when a development site is planned around some pollutant sources in a residential development plan, it is evaluated and reviewed whether the site meets the risk criteria through a current concentration survey of major hazardous air pollutants. This study prepared a quantitative method to confirm the validity of the location of the residential area to be developed in the residential development plan and proposed a plan to expand the project subject to HIA within the EIA procedure. A detailed methodology was proposed by reviewing the screening and scoping procedures of the EIA system, and a case analysis of the urban development plan discussed in the past was conducted to verify the methodology.

• Earthquakes and Structures
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• v.13 no.1
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• pp.79-87
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• 2017

Seismic analysis of local site conditions is fundamental for a reliable site seismic hazard assessment. It plays a major role in mitigation of seismic damage potential through the prediction of surface ground motion in terms of amplitude, frequency content and duration. Such analysis requires the determination of the transfer function, which is a simple tool for characterizing a soil profile by estimating its vibration frequencies and its amplification potential. In this study, numerical simulations are carried out and are then combined with a statistical study to allow the characterization of design sites classified by the Algerian Building Seismic Code (RPA99, ver 2003), by average transfer functions. The mean transfer functions are thereafter used to compute RPA99 average site factors. In this regard, coming up seismic fields are simulated based on Power Spectral Density Functions (PSDF) defined at the rock basement. Results are also used to compute average site factor where, actual and synthetic time histories are introduced. In absence of measurement data, it is found that the proposed approach can be used for a better soil characterization.

• Journal of Korean Critical Care Nursing
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• v.15 no.3
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• pp.75-87
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• 2022

Purpose : This retrospective investigation study aimed to determine the predictive validity of superficial surgical site infection assessment tools by measuring the risk score at the surgical site. Methods : This study included patients hospitalized to the general surgery department of a Hospital from January 2021 to December 31, 2021. The inclusion criteria were age ≥19 years, general abdominal surgery under general anesthesia, and hospital stay longer than 2 days. Patients who had undergone transplantation were excluded. Results : Tool validity results showed that tools including surgical time and operative procedure were more accurate than previously developed tools, with a sensitivity of 71.1%, specificity of 71.4%, positive prediction of 12.3%, negative prediction of 97.8%, and area under the curve of 0.743 (95% confidence interval, 0.678~0.745). The tool's cut-off score was 15, and the risks of infection was increased by 6.14 times at or above this cut-off point. Preoperative hair removal period, surgical wound classification, surgery time, body temperature on the second day after surgery, drainage tube type, and suture type affected the risk of infection at the surgical site. Conclusion : The incidence of healthcare-associated infections has been declining in the past decade; however, surgical site infections still account for a considerable proportion. Therefore, early identification of high-risk groups for surgical site infection is crucial for reducing the incidence of surgical site infection using appropriate management.

• Journal of Environmental Impact Assessment
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• v.30 no.4
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• pp.215-224
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• 2021

In this study, to investigate the effect of stabilization of Pb-contaminated soil near a smelter site for the reduction of environmental risk of Pb leaching, commercial stabilizers were amended with the Pb-contaminated soil and evaluated leaching characteristics of Pb in soil by TCLP and SPLP leaching test. Also, performing sequential extraction procedure speciation of Pb in the amended soil was investigated. Limestone, AC-2 (Amron), Metafix (Peroxychem) that possess stabilization performance towards heavy metal in soil and mass production is available were selected as candidates. AC-2 contained a CaCO₃ and MgO crystalline phase, while Metafix had a Fe₇S₈ crystalline phase, according to XRD studies. Pb content in SPLP extract was lower than the South Korean drinking water standard for Pb in groundwater at 4% AC-2 and Metafix treatment soil, and TCLP-based stabilization effectiveness was more than 90%. The findings of the sequential extraction method of soil treated with Metafix revealed that fractions 1 and 2 of Pb, which correspond to relatively high mobility and bioavailable fractions, were lowered, while the residual fraction (fraction 5) was raised. As a consequence, the order of performance for Pb stabilization in polluted soil was Metafix>AC-2>limestone.

• Earthquakes and Structures
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• v.20 no.2
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• pp.133-148
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• 2021

The paper presents a simplified force-based seismic design procedure for the preliminary design of steel haunch retrofitting for the seismic upgrade of deficient RC frames. The procedure involved constructing a site-specific seismic design spectrum for the site, which is transformed into seismic base shear coefficient demand, using an applicable response modification factor, that defines base shear force for seismic analysis of the structure. Recent experimental campaign; involving shake table testing of ten (10), and quasi-static cyclic testing of two (02), 1:3 reduced scale RC frame models, carried out for the seismic performance assessment of both deficient and retrofitted structures has provided the basis to calculate retrofit-specific response modification factor Rretrofitted. The haunch retrofitting technique enhanced the structural stiffness, strength, and ductility, hence, increased the structural response modification factor, which is mainly dependent on the applied retrofit scheme. An additional retrofit effectiveness factor (ΩR) is proposed for the deficient structure's response modification factor Rdeficient, representing the retrofit effectiveness (ΩR=Rretrofitted /Rdeficient), to calculate components' moment and shear demands for the retrofitted structure. The experimental campaign revealed that regardless of the deficient structures' characteristics, the ΩR factor remains fairly the unchanged, which is encouraging to generalize the design procedure. Haunch configuration is finalized that avoid brittle hinging of beam-column joints and ensure ductile beam yielding. Example case study for the seismic retrofit designs of RC frames are presented, which were validated through equivalent lateral load analysis using elastic model and response history analysis of finite-element based inelastic model, showing reasonable performance of the proposed design procedure. The proposed design has the advantage to provide a seismic zone-specific design solution, and also, to suggest if any additional measure is required to enhance the strength/deformability of beams and columns.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.4
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• pp.229-237
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• 2023

In this research, a new Test and Evaluation (T&E) procedure for defense AI systems is proposed to fill the existing gap in established methodologies. This proposed concept incorporates a data-based performance evaluation, allowing for independent assessment of AI model efficacy. It then follows with an on-site T&E using the actual AI system. The performance evaluation approach adopts the project promotion framework from the defense acquisition system, outlining 10 steps for R&D projects and 9 steps for procurement projects. This procedure was crafted after examining AI system testing standards and guidelines from both domestic and international civilian sectors. The validity of each step in the procedure was confirmed using real-world data. This study's findings aim to offer insightful guidance in defense T&E, particularly in developing robust T&E procedures for defense AI systems.

• Toxicological Research
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• v.6 no.2
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• pp.205-213
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• 1990

The regulation of neurotoxicants has usually been based upon setting reference doses by dividing a no observed adverse effect level (NOAEL) by uncertainty factors that theoretically account for interspecies and intraspecies extraploation of experimental results in animals to humans. Recently, we have proposed a four-step alternative procedure which provides quantitative estimates of risk as a function of dose. The first step is to establish a mathematical relationship between a biological effect or biomarker and the dose of chemical administered. The second step is to determine the distribution (variability) of individual measurements of biological effects or their biomarkers about the dose response curve. The third step is to define an adverse or abnormal level of a biological effect or biomarker in an untreated population. The fourth and final step is to combine the information from the first three steps to estimate the risk (proportion of individuals exceeding on adverse or abnormal level of a biological effect or biomarker) as a function of dose. The primary purpose of this report is to enhance the certainty of the first step of this procedure by improving our understanding of the relationship between a biomarker and dose of administered chemical. Several factors which need to be considered include: 1) the pharmacokinetics of the parent chemical, 2) the target tissue concentrations of the parent chemical or its bioactivated proximate toxicant, 3) the uptake kinetics of the parent chemical or metabolite into the target cell(s) and/or membrane interactions, and 4) the interaction of the chemical or metabolite with presumed receptor site(s). Because these theoretical factors each contain a saturable step due to definitive amounts of required enzyme, reuptake or receptor site(s), a nonlinear, saturable dose-response curve would be predicted. In order to exemplify this process, effects of the neurotoxicant, methlenedioxymethamphetamine (MDMA), were reviewed and analyzed. Our results and those of others indicate that: 1) peak concentrations of MDMA and metabolites are ochieved in rat brain by 30 min and are negligible by 24 hr, 2) a metabolite of MDMA is probably responsible for its neurotoxic effects, and 3) pretreatment with monoamine uptake blockers prevents MDMA neurotoxicity. When data generated from rats administerde MDMA were plotted as bilolgical effect (decreases in hippocampal serotonin concentrations) versus dose, a saturation curve best described the observed relationship. These results support the hypothesis that at least one saturable step is involved in MDMA neurotoxicity. We conclude that the mathematical relationship between biological effect and dose of MDMA, the first step of our quantitative neurotoxicity risk assessment procedure, should reflect this biological model information generated from the whole of the dose-response curve.