• Title/Summary/Keyword: Model Assessment

Search Result 6,399, Processing Time 0.037 seconds

Towards Quantitative Assessment of Human Exposures to Indoor Radon Pollution from Groundwater

  • Donghan Yu;Lee, Han-Soo
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.17 no.E2
    • /
    • pp.43-51
    • /
    • 2001
  • A report by the national research council in the United States suggested that many lung cancer deaths each year be associated with breathing radon in indoor air. Most of the indoor radon comes directly from soil beneath the basement of foundations. Recently, radon released from groundwater is found to contribute to the total inhalation risk from indoor air. This study presents the quantitative assessment of human exposures to radon released from the groundwater into indoor air. At first, a three-compartment model is developed to describe the transfer and distribution of radon released from groundwater in a house through showering, washing clothes, and flushing toilets. Then, to estimate a daily human exposure through inhalation of such radon for an adult. a physiologically-based pharmacokinetic(PBPK) model is developed. The use of a PBPK model for the inhaled radon could provide useful information regarding the distribution of radon among the organs of the human body. Indoor exposure patterns as input to the PBPK model are a more realistic situation associated with indoor radon pollution generated from a three-compartment model describing volatilization of radon from domestic water into household air. Combining the two models for inhaled radon in indoor air can be used to estimate a quantitative human exposure through the inhalation of indoor radon for adults based on two sets of exposure scenarios. The results obtained from the present study would help increase the quantitative understanding of risk assessment issues associated with the indoor radon released from groundwater.

  • PDF

Probabilistic bearing capacity assessment for cross-bracings with semi-rigid connections in transmission towers

  • Zhengqi Tang;Tao Wang;Zhengliang Li
    • Structural Engineering and Mechanics
    • /
    • v.89 no.3
    • /
    • pp.309-321
    • /
    • 2024
  • In this paper, the effect of semi-rigid connections on the stability bearing capacity of cross-bracings in steel tubular transmission towers is investigated. Herein, a prediction method based on the hybrid model which is a combination of particle swarm optimization (PSO) and backpropagation neural network (BPNN) is proposed to accurately predict the stability bearing capacity of cross-bracings with semi-rigid connections and to efficiently conduct its probabilistic assessment. Firstly, the establishment of the finite element (FE) model of cross-bracings with semi-rigid connections is developed on the basis of the development of the mechanical model. Then, a dataset of 7425 samples generated by the FE model is used to train and test the PSO-BPNN model, and the accuracy of the proposed method is evaluated. Finally, the probabilistic assessment for the stability bearing capacity of cross-bracings with semi-rigid connections is conducted based on the proposed method and the Monte Carlo simulation, in which the geometric and material properties including the outer diameter and thickness of cross-sections and the yield strength of steel are considered as random variables. The results indicate that the proposed method based on the PSO-BPNN model has high accuracy in predicting the stability bearing capacity of cross-bracings with semi-rigid connections. Meanwhile, the semi-rigid connections could enhance the stability bearing capacity of cross-bracings and the reliability of cross-bracings would significantly increase after considering semi-rigid connections.

The Process Reference Model for the Data Quality Management Process Assessment (데이터 품질관리 프로세스 평가를 위한 프로세스 참조모델)

  • Kim, Sunho;Lee, Changsoo
    • The Journal of Society for e-Business Studies
    • /
    • v.18 no.4
    • /
    • pp.83-105
    • /
    • 2013
  • There are two ways to assess data quality : measurement of data itself and assessment of data quality management process. Recently maturity assessment of data quality management process is used to ensure and certify the data quality level of an organization. Following this trend, the paper presents the process reference model which is needed to assess data quality management process maturity. First, the overview of assessment model for data quality management process maturity is presented. Second, the process reference model that can be used to assess process maturity is proposed. The structure of process reference model and its detail processes are developed based on the process derivation approach, basic principles of data quality management and the basic concept of process reference model in SPICE. Furthermore, characteristics of the proposed model are described compared with ISO 8000-150 processes.

New Environmental Impact Assessment Technology (신환경영향평가기술(新環境影響評價技術)의 개발방향(開發方向))

  • Han, Sang-Wook;Lee, Jong-Ho;Nam, Young-Sook
    • Journal of Environmental Impact Assessment
    • /
    • v.9 no.4
    • /
    • pp.277-290
    • /
    • 2000
  • The purpose of this study is to identify the problems of environmental impact assessment(EIA) and to suggest new EIA technology. The problems of EIA in Korea can be summarized as follows. First, the EIA does not reflect the impact of policy, plan and program on environment. Second, the project EIA does not consider the cumulative impacts such as additive impacts, synergistic impacts, threshold/saturation impacts, induced and indirect impacts, time-crowded impacts, and space-crowded impacts. Third, the EIA techniques in Korea are not standardized. Finally, the present EIA suggests only alternatives to reduce adverse impacts. To solve above-mentioned problems, the development of new EIA technology is essential. First, the new EIA technology should be developed toward pollution prevention technology and comprehensive and integrated environmental management technology. Second, new fields of EIA for pollution prevention contain strategic environmental assessment, cumulative impacts assessment, socio-economic impact assessment, cyber EIA and EIA technology necessary after the reunification of Korean Peninsula. Third, EIA technology for integrated environmental management contains the development of integated environment assessment system and the development of packaged EIA technology. The EIA technology for integrated environmental assessment system contains (1) development of integrated impact assessment technology combining air/water quality model, GIS and remote sensing, (2) integrated impact assessment of EIA, traffic impact assessment, population impact assessment and disaster impact assessment. (3) development of integrated technology combining risk assessment and EIA (4) development of integrated technology of life cycle assessment and EIA, (5) development of integrated technology of spatial planning and EIA, (6) EIA technology for biodiversity towards sustainable development, (7) mathematical model and GIS based location decision techniques, and (8) environmental monitoring and audit. Furthermore, there are some fields which need packaged EIA technology. In case of dam development, urban or industrial complex development, tourist development, landfill or combustion facilities construction, electric power plant development, development of port, road/rail/air port, is necessary the standardized and packaged EIA technology which considers the common characteristics of the same kind of development project.

  • PDF

A Study on Improvement Method of Assessment Model of Interoperability based on LISI in Weapon Systems (LISI 기반의 무기체계 상호운용성 평가모델 개선방안 연구)

  • Yu, Chul-Hi;Lee, Tae-Gong;Lim, Jae-Sung
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.35 no.11B
    • /
    • pp.1715-1724
    • /
    • 2010
  • This paper analyzes the limitations and provides alternative options for Korean Military LISI model, which is based on interoperability assessment model, LISI(Level of Information System Interoperability), developed for US defense information systems and reformed to suit the Korean Military environment by ADD. Korean Military's LIST model is applied to all systems(information system, weapon systems, non-weapon systems)' interoperability assessment defined in acquisition regulations by Joint Interoperability Test Center, a subordinate unit of Defense Command and Control Forces and the only assessment agency of defense interoperability. LISI was basically developed as an assessment model for information system's interoperability, but due to it's shortfall in assessing complex systems including information systems, weapon and non-weapon systems required from New environment SOSI(System of Systems Interoperability) has recently been researched and developed. On the other hand, it is inevitable that Korean Military's LISI model face fundamental limitations as an interoperability assessment tool for Defense Information System as well as for weapon and non-weapon systems, since it was benchmarked and reformed from the US LISI model. In order to overcome such limitations, MND and associated agencies are providing improvement methods through studies. This paper will provide LISI capability model's assessment criteria on Application(P), Infrastructure(I), Data(D), restraints of on comparison assessment process of unit systems evaluated and politic alternatives to overcome the restraints.

Simulation and Performance Assessment of a Geiger-mode Imaging LADAR System (가이거모드 영상 LADAR 시스템의 시뮬레이션과 성능예측)

  • Kim, Seongjoon;Lee, Impyeong;Lee, Youngcheol
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.15 no.5
    • /
    • pp.687-698
    • /
    • 2012
  • LADAR systems can rapidly acquire 3D point clouds by sampling the target surfaces using laser pulses. Such point clouds are widely used for diverse applications such as DSM/DTM generation, forest biomass estimation, target detection, wire avoidance and so on. Many kinds of LADAR systems have been developed with their respective purposes and applications. Particularly, Geiger mode imaging LADAR systems are increasingly utilized since they are energy efficient thank to extremely sensitive detectors incorporated into the systems. The purpose of this research is the performance assessment of a Geiger mode imaging LADAR system based on simulation with the real system parameters. We thus developed a simulation method of such a LADAR system by modeling its geometric, radiometric, optic and electronic aspects. Based on the simulation, we performed the performance assessment of a newly designed system to derive the outlier ratio and false alarm rate expected during its operation in almost real environment with reasonable system parameters. The proposed simulation and performance assessment method will be effectively utilized for system design and optimization, and test data generation.

Development of Monthly Hydrological Cycle Assessment System Using Dynamic Water Balance Model Based on Budyko Framework (Budyko 프레임워크 기반 동적 물수지 모형을 활용한 월 단위 물순환 평가체계 개발)

  • Kim, Kyeung;Hwang, Soonho;Jun, Sang-Min;Lee, Hyunji;Kim, Sinae;Kang, Moon Seong
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.64 no.2
    • /
    • pp.71-83
    • /
    • 2022
  • In this study, an indicator and assessment system for evaluating the monthly hydrological cycle was prepared using simple factors such as the landuse status of the watershed and topographic characteristics to the dynamic water balance model (DWBM) based on the Budyko framework. The parameters a1 of DWBM are introduced as hydrologic cycle indicators. An indicator estimation regression model was developed using watershed characteristics data for the introduced indicator, and an assessment system was prepared through K-means cluster analysis. The hydrological cycle assessment system developed in this study can assess the hydrological cycle with simple data such as land use, CN, and watershed slope, so it can quickly assess changes in hydrological cycle factors in the past and present. Because of this advantage is expected that the developed assessment system can predict changes in the hydrological cycle and use an auxiliary tool for policymaking.

An Experimental Study on IMO 2nd Generation Stability Assessment in Dead Ship Condition of 13K Chemical Tanker (13K Chemical Tanker의 기관 제어 불능상태 IMO 2세대 안정성 평가에 관한 실험적 연구)

  • Lee, Sang-Beom;Moon, Byung-Young
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.59 no.2
    • /
    • pp.89-95
    • /
    • 2022
  • The stability of the existing ships has been evaluated through numerical calculations in the steady-state, but recently the IMO proposed a new stability assessment criteria that the stability is evaluated in the state in which environmental loads from such as waves and wind act like the loads under actual ship operating conditions. In this study, IMO 2nd generation stability assessment method and procedure were summarized for the dead ship condition, and Direct Stability Assessment (DSA) was performed on 13K chemical tanker through basin model test. The model test is performed in the ocean engineering basin to implement wave and wind loads, and environmental conditions for waves were set height and period of the incident wave, considering the regular wave and wind generation range reproducible in the ocean engineering basin. In addition, to consider the effect of wind speed, the Beaufort Scale for wind speed was applied in the model test.

Efficient Data Management for Hull Condition Assessment

  • Jaramillo, David;Cabos, Christian;Renard, Philippe
    • International Journal of CAD/CAM
    • /
    • v.6 no.1
    • /
    • pp.9-17
    • /
    • 2006
  • Performing inspections for Hull Condition Monitoring and Assessment as stipulated in IACS unified requirements and IMO's Condition Assessment Scheme (CAS) IMO Resolution MEPC.94(46), 2001, Condition Assessment Scheme, IMO Resolution MEPC.111(50), 2003, Amendments to regulation 13G, addition of new regulation 13H involves a huge amount of measurement data to be collected, processed, analysed and maintained. Information to be recorded consists of thickness measurements and visual assessment of coating and cracks. The amount of data and increasing requirements with respect to condition assessment demand efficient computer support. Currently, due to the lack of standardization for this kind of data, the thickness measurements are recorded manually on ship drawings or tables. In this form, handling of the measurements is tedious and error-prone and assessment is difficult. Data reporting and analysis takes a long time, leading to some repairs being performed only at the next docking of the ship or making an additional docking necessary. The recently started ED funded project CAS addresses this topic and develops-as a first step-a data model for Hull Condition Monitoring and Assessment (HCMA) based on XML-technology. The model includes simple geometry representation to facilitate a graphically supported data collection as well as an easy visualisation of the measurement results. In order to ensure compatibility with the current way of working, the content of the data model is strictly confined to the requirements of the measurement process. Appropriate data interfaces to classification software will enable rapid assessment by the classification societies, thus improving the process in terms of time and cost savings. In particular, decision-making can be done while the ship is still in the dock for maintenance.

The Risk Assessment Effects of SCM and the Strategy of Risk Management on Supply Chain Performance (공급사슬 위험평가 및 위험관리전략이 공급사슬 운영성과에 미치는 영향)

  • Kim, Dong Jeong;Lee, Young Jai
    • Journal of Information Technology Applications and Management
    • /
    • v.21 no.4
    • /
    • pp.173-186
    • /
    • 2014
  • This study outlines possible risk factors in the SCM of a company and correlates risk assessment, the strategy of risk management, and the supply chain performance. The data is surveyed from an international Korean company and is analyzed by the structure equation model of actual proof. The research model verifies the correlation between the risk assessment, the strategy of risk management, and the supply chain performance as dependent variables after the risk factors of the SCM are defined as independent variables. The research shows that there are consecutive links among the risk factors of the SCM, the risk assessment, and the strategy of risk management. The strategy of risk management was conclusively determined to have an effect on supply chain performance. Therefore, improving the supply chain performance of a company requires the constructive process for risk management based on a correlation between risk assessment and the strategy of risk management.