• Title/Summary/Keyword: Quantitative Estimation

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Estimation of the Liability Risk for Release of Chemicals at Chemical Plant (화학플랜트에서의 화학물질 누출사고에 대한 배상책임 위험도 산정)

  • Moon, Jung Man;Park, Dal Jae
    • Korean Chemical Engineering Research
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    • v.58 no.3
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    • pp.438-449
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    • 2020
  • This study is to improve the method of calculating the risk of liability that arise from release and dispersion of chemicals outside the plant in process industries such as chemical and petrochemical plants. To achieve this goal, the correlation factors with the risk of chemical release accident is derived by simulating release and dispersion of substances (14 types) designated by Ministry of Environment as preparation for accident, analyzing the cases of chemical release and effects of plant life damage. The method of calculating chemical liability risk was modified and supplemented based on the results obtained from the study. The correlation coefficient between the probit value of 14 chemical types and the liability risk by EURAM (European Union Risk Ranking Method) was -0.526, while the correlation coefficient with the modified chemical release accident risk was 0.319. Thus, the value from modified method shows that they appear to be correlated. According to modified calculating methodology, the correlation between ERPG-2 value and liability risk of 97 chemical types was -0.494 which is 19 times higher than existing liability risk correlation as absolute value. And the correlation coefficient of corrosion risk was 0.91. The standardized regression coefficients (β) value of correlation factors that affected the increase and decrease of risk were derived in order of Corrosion Index(0.713), ERPG-2 (0.400) and NFPA Health Index (0.0680) by values. It is expected that these findings this study result will also enable the calculation of reasonable chemical release liability risk for existing and new chemical, and will help use them as quantitative liability risk management indicators for chemical plant site.

Dose-Response Relationship of Avian Influenza Virus Based on Feeding Trials in Humans and Chickens (조류인플루엔자 바이러스의 양-반응 모형)

  • Pak, Son-Il;Lee, Jae-Yong;Jeon, Jong-Min
    • Journal of Veterinary Clinics
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    • v.28 no.1
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    • pp.101-107
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    • 2011
  • This study aimed to determine dose-response (DR) curve of avian influenza (AI) virus to predict the probability of illness or adverse health effects that may result from exposure to a pathogenic microorganism in a quantitative microbial risk assessment. To determine the parametric DR relationship of several strains of AI virus, 7 feeding trial data sets challenging humans (5 sets) and chickens (2 sets) for strains of H3N2 (4 sets), H5N1 (2 sets) and H1N1 (1 set) from the published literatures. Except for one data set (study with intra-tracheal inoculation for data set no. 6), all were obtained from the studies with intranasal inoculation. The data were analyzed using three types of DR model as the basis of heterogeneity in infectivity of AI strains in humans and chickens: exponential, beta-binomial and beta-Poisson. We fitted to the data using maximum likelihood estimation to get the parameter estimates of each model. The alpha and beta values of the beta-Poisson DR model ranged 0.06-0.19 and 1.7-48.8, respectively for H3N2 strain. Corresponding values for H5N1 ranged 0.464-0.563 and 97.3-99.4, respectively. For H1N1 the parameter values were 0.103 and 12.7, respectively. Using the exponential model, r (infectivity parameter) ranged from $1.6{\times}10^{-8}$ to $1.2{\times}10^{-5}$ for H3N2 and from $7.5{\times}10^{-3}$ to $4.0{\times}10^{-2}$ for H5N1, while the value was $1.6{\times}10^{-8}$ for H1N1. The beta-Poisson DR model provided the best fit to five of 7 data sets tested, and the estimated parameter values in betabinomial model were very close to those of beta-Poisson. Our study indicated that beta-binomial or beta-Poisson model could be the choice for DR modeling of AI, even though DR relationship varied depending on the virus strains studied, as indicated in prior studies. Further DR modeling should be conducted to quantify the differences among AI virus strains.

A study on the estimation of river water intake using the operating time of the pumping station (양수장의 가동시간을 이용한 하천수 취수량 산정방안 연구)

  • Baek, Jongseok;Kim, Chiyoung;Cha, Jun-Ho;Song, Jaehyun
    • Journal of Korea Water Resources Association
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    • v.53 no.2
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    • pp.89-96
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    • 2020
  • Water management agencies under the Ministry of Environment produce and accumulate qualified basic data for major rivers. However, the integrated management of the river water has been weak since the artificial water circulation process, such as the intaking and drainage of agricultural water, has not been examined in the basin, which includes many agricultural land. In this study, a study was conducted on how the power usage method (operating time method) based on the running time can be applied and improved among indirect flow rate measurement methods used to investigate flow rates collected by the riverside for agricultural water purposes, and thus the resultant data of high reliability can be obtained at low cost. The operation time method is suitable for small-scale water pumping stations where it is difficult to secure real-time power supply data. The reliability of the data was verified through the correlation analysis with the actual flow rate, and it was found that the flow rate calculated by the operation time method reflecting the level of the stream to which the inlet of the pumping station is connected can be reasonably matched with the actual flow rate. In addition, it was confirmed that the investment cost at the time of initial installation of the facility was highly efficient by generating qualified flow data at low cost through comparison with direct flow rate measurement methods. If flow data is secured by applying the operation time method to large and small water farms located along the riverside, it is expected that more quantitative and integrated stream water management will be possible.

The Study on Optimal Image Processing and Identifying Threshold Values for Enhancing the Accuracy of Damage Information from Natural Disasters (자연재해 피해정보 산출의 정확도 향상을 위한 최적 영상처리 및 임계치 결정에 관한 연구)

  • Seo, Jung-Taek;Kim, Kye-Hyun
    • Spatial Information Research
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    • v.19 no.5
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    • pp.1-11
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    • 2011
  • This study mainly focused on the method of accurately extracting damage information in the im agery change detection process using the constructed high resolution aerial im agery. Bongwha-gun in Gyungsangbuk-do which had been severely damaged from a localized torrential downpour at the end of July, 2008 was selected as study area. This study utilized aerial im agery having photographing scale of 30cm gray image of pre-disaster and 40cm color image of post-disaster. In order to correct errors from the differences of the image resolution of pre-/post-disaster and time series, the prelim inary phase of image processing techniques such as normalizing, contrast enhancement and equalizing were applied to reduce errors. The extent of the damage was calculated using one to one comparison of the intensity of each pixel of pre-/post-disaster im aged. In this step, threshold values which facilitate to extract the extent that damage investigator wants were applied by setting difference values of the intensity of pixel of pre-/post-disaster. The accuracy of optimal image processing and the result of threshold values were verified using the error matrix. The results of the study enabled the early exaction of the extents of the damages using the aerial imagery with identical characteristics. It was also possible to apply to various damage items for imagery change detection in case of utilizing multi-band im agery. Furthermore, more quantitative estimation of the dam ages would be possible with the use of numerous GIS layers such as land cover and cadastral maps.

Risk-based Safety Impact Assessment for Construction Projects (위험도 접근방법에 의한 건설사업 안전영향평가방안에 관한 연구)

  • Choi Hyun-Ho;Jung Pyung-Ki;Seo Jong-Won;Choi Ook
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • 2004.11a
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    • pp.504-509
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    • 2004
  • Safety assessment of construction projects may be affected by various factors such as types and scale of projects, construction methods, procedure, climactic, and site conditions etc. Presently, in planning and design phases, designers are still often uncertain of their responsibilities, l3i]I information and training of safety. Therefore, designers are still failing to exploit the potential that have to eliminate and reduce risks on site. In this study, the concepts of safety impact assessment is introduced in order to derive the performing design for safety in design phase. For this purpose, a framework for safety impact assessment model using risk-based approach for construction projects is suggested. The suggested model includes of information survey and scenarios, classification of safety impact factors occurred by design and construction, and quantitative estimation of magnitude and frequency. Moreover, the checklist which is enable to identify relationship between safety impact factors and design factors is developed and the methodology of safety impact assessment model using risk-based approach is also proposed.

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Optimum Carbonation Reforming Period of Recycled Aggregate Based on the Microscopic Carbonation Conduct (미시적 탄산화 거동에 기초한 순환 골재의 최적 탄산화 개질 기간)

  • Shin, Jin-Hak;Kim, Han-Sic;Ha, Jung-Soo;Chung, Lan
    • Journal of the Korea Concrete Institute
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    • v.28 no.3
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    • pp.329-340
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    • 2016
  • Increase in demotion and repair works on buildings in the construction market generates a large amount of construction waste. Recycling of construction waste is important for saving of resources, preservation of environment and constant advance of the construction industry. Accordingly, the environmental and economic value of recycled aggregate, which is produced after waste concrete is crushed, is increasingly highlighted. It is generally known that compared to concrete made of ordinary aggregate, concrete made of recycled aggregate has low quality, and the low quality is dependent on the amount of the bonding heterogeneous (cement paste and mortar) as well as the amount of the pores within the bonding heterogeneous. Reports on carbonation mechanism shows that the pores of cement-based materials are filled up by the progress of carbonation. Therefore, this study aims at an estimation of the period for optimum carbonation reforming appropriate for the thickness of the bonding heterogeneous of recycled aggregate, based on carbonation mechanism, with a view to improving the product quality by means of filling up the pores of the bonding heterogeneous of recycled aggregate. This study drew the carbonation depth according to the passage of age by calculating the bonding ratio and bonding thickness of the bonding heterogeneous as against the particle size distribution of recycled aggregate as well as by chemical quantitative analysis according to the age of accelerated carbonation of mock-up samples imitating bonding heterogeneous. Based on the correlation between the age of accelerated carbonation and carbonation depth, this study also proposed the estimated period of carbonation reforming of recycled aggregate appropriate for the thickness of the bonding heterogeneous.

Rethinking Theoretical and Practical Issues of Economic Valuation of Library Services (도서관 서비스의 경제적 가치 측정의 이론적, 실제적 검토)

  • Shim, Won-Sik
    • Journal of the Korean Society for Library and Information Science
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    • v.44 no.4
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    • pp.231-247
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    • 2010
  • This research examines a number of theoretical and practical issues when measuring the economic value of library services. In particular, using two recent studies conducted in Korea as illustrations, the study shows how various measurement decisions affect the final outcomes in the economic valuation of library services and thus points to the need for a more reliable study design. Specific areas of measurement discussed include the following: scope of measurement, application of CVM(Contingent Valuation Method), time vs. monetary value measurement, dealing with outliers, allowing alternatives, and the use of estimation. ROI(Return on Investment) scores or benefit cost ratios vary significantly according to different measurement choices even in the same study. There is a need for collecting qualitative data that complements the quantitative data typically collected in economic valuation studies. The outcome of economic valuation of library services should be considered as one of many representations of library values. Practitioners and researchers should exercise caution in interpreting those results but be able to leverage them to better communicate the value of library services.

Estimation of Air-Sea Heat Exchange Using BUOY Data at the Yellow Sea, Korea (부이 관측자료를 이용한 서해 해역의 해양-대기 열교환량 산출)

  • kang, Yune-Jeung;Hwang, Seung-On;Kim, Tae-Hee;Nam, Jae-Cheol
    • Journal of the Korean earth science society
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    • v.22 no.1
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    • pp.40-46
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    • 2001
  • Heat exchange between the atmosphere and sea is produced using the data from two 3m discus buoy installed by KMA in 1996. The meteorological and oceanic characteristics at the Dukjukdo and Chilbaldo buoy for the period 1996 ${\sim}$ 2000 are discussed. Daily averaged sensible heat and latent heat flux at each site are estimated from bulk aerodynamic method using given data and analyzed. Quantitative analyses show SST indicates 1-year cycle like air temperature but has 1 month lag. Sea level pressure is lowest in July, humidity is higher from May to August, and wind speed has averaged value of 5 m/s and higher in autumn and winter. Sensible heat flux analyses present that strong heat loss from the sea occurs in autumn and winter and weak heat loss from atmosphere appears in spring and summer, and net sensible heat loss from the sea is found throughout the year. The ocean significantly releases latent heat into atmosphere from August to May but get a little latent heat from atmosphere in other months. Net latent heat loss from the sea is larger than net sensible heat loss except in January and February. Comparison with two sites suggests that the magnitude of heat flux and their fluctuation are generally stronger at Dukjukdo than at Chilbaldo. In case study, both sensible and latent heat flux is a little more at Chilbaldo in March 1998, but substantially stronger at Dukjukdo in November 1996.

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Linkage Disequilibrium Estimation of Chinese Beef Simmental Cattle Using High-density SNP Panels

  • Zhu, M.;Zhu, B.;Wang, Y.H.;Wu, Y.;Xu, L.;Guo, L.P.;Yuan, Z.R.;Zhang, L.P.;Gao, X.;Gao, H.J.;Xu, S.Z.;Li, J.Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.6
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    • pp.772-779
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    • 2013
  • Linkage disequilibrium (LD) plays an important role in genomic selection and mapping quantitative trait loci (QTL). In this study, the pattern of LD and effective population size ($N_e$) were investigated in Chinese beef Simmental cattle. A total of 640 bulls were genotyped with IlluminaBovinSNP50BeadChip and IlluminaBovinHDBeadChip. We estimated LD for each autosomal chromosome at the distance between two random SNPs of <0 to 25 kb, 25 to 50 kb, 50 to 100 kb, 100 to 500 kb, 0.5 to 1 Mb, 1 to 5 Mb and 5 to 10 Mb. The mean values of $r^2$ were 0.30, 0.16 and 0.08, when the separation between SNPs ranged from 0 to 25 kb to 50 to 100 kb and then to 0.5 to 1 Mb, respectively. The LD estimates decreased as the distance increased in SNP pairs, and increased with the increase of minor allelic frequency (MAF) and with the decrease of sample sizes. Estimates of effective population size for Chinese beef Simmental cattle decreased in the past generations and $N_e$ was 73 at five generations ago.

The Fuzzy QFD Approach to Importance the Public Sector Information Performance Measurement Category (퍼지 QFD를 활용한 공공부문 정보화 성과 측정범주 중요도 도출)

  • Oh, Jin-Seok;Song, Young-Il
    • Information Systems Review
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    • v.12 no.2
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    • pp.189-203
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    • 2010
  • Is presenting guidance of information performance measurement as government PRM version 2.0 these common reference models in public sector. Government PRM is consisted of assessment classification system and standard line of sight and performance management standard form. Through this, is sorting performance element and define cause-and effect. Government PRM is supplying measurement categories at assessment classification system, but relative importance for application standard by measurement categories is not presenting. In this study, importance for government PRM's measurement categories been applying by commonness Test of information performance measurement of public sector wishes to deduce estimation and priority. Research model used Fuzzy QFD, and designed so that can reflect well PRM's development purpose. I applied Fuzzy AHP and FPP method that graft together fuzzy theory to minimize uncertainty and ambiguity in that expert opinion. Is drawn to element that "Standard model offer for information department and management" is the most important in government PRM's development purpose. "Quality of service" is showing the highest priority in customer results in measurement category. Importance for government PRM's measurement categories can offer common valuation basis in government and public institution. Hereafter if examine closely quantitative cause-and effect for structure model of measurement classification system when study government PRM more objective and efficient reference model become.