• Title/Summary/Keyword: Process investigation

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The Pre-Results Of Geomorphological Investigation In Tui River Basin

  • Narangerel, S.;Enkhtaivan, D.
    • The Korean Journal of Quaternary Research
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    • v.22 no.2
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    • pp.43-44
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    • 2008
  • In this brief present are about some advanced results from investigation geomorphology in basin of river Tui and distribution of relief their peculiarities, types morphogenetic, convert to ekzogen process of relief ( fluvial system, permafrost process, wind process, slope process etc) and dynamic process of sedimentation.

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Cost-effective Investigation on Contaminated Land and Assessment of Measurement Uncertainty (오염토양의 효율적 조사기법과 측정불확도의 평가방법)

  • 이종천
    • Economic and Environmental Geology
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    • v.37 no.1
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    • pp.49-59
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    • 2004
  • The concectration and distribution of contaminants obtained from a contaminated land investigation or an environmental geochemistry survey constitutes the basis of a decision-making process on environmental policies or of scientific researches. As the quality of data determines the reliability of the result, the investigation plan should be adjusted according to the purpose of the investigation. In general, the effort to improve the data quality had been focused mainly on the QA/QC procedures in laboratories. The rapid progress of analytical instrument has also contributed toward improving the analytical precision to a sacrificable degree. Nevertheless, in many cases, it is not the analytical precision that needs improvement for the better precision of overall measurement process: it is rather during the sampling process in the field that is responsible for the poor precision. To assess the data quality on a measured value, ISO recommends to provide information on "measurement uncertainty" along with the measured value. The measurement uncertainty in an environmental measurement context can be explained as the statistical number that expresses the degree of the uncertainty stemming from the sampling and analytical procedures. There is a cost involved in order to improve the precision of sampling and analytical methods so as to decrease the degree of measurement uncertainty. The economical point of compromise in an investigation planning can be achieved when the allowable degree of uncertainty has been set before-hand. The investigation can then be planned accordingly not to exceed the uncertainty limit. Furthermore, if the measurement uncertainty estimated from the preliminary investigation can be separated into sampling and analytical uncertainties, it can be used as a criterion where the resources for the investigation should be allotted cost-effectively to reinforce the weakest link of the whole investigation process. This paper aims to present a method of estimating the level of measurement uncertainty of a measured contamination concentration at a site used as an example and to show how the estimated uncertainty can be applied to serve the particular purpose of an investigation.

Development of a Human Factors Investigation and Analysis Model for Use in Maritime Accidents: A Case Study of Collision Accident Investigation

  • Kim, Hong-Tae;Na, Seong
    • Journal of Navigation and Port Research
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    • v.41 no.5
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    • pp.303-318
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    • 2017
  • In the shipping industry, it is well known that around 80 % or more of all marine accidents are caused fully or at least in part by human error. In this regard, the International Maritime Organization (IMO) stated that the study of human factors would be important for improving maritime safety. Consequently, the IMO adopted the Casualty Investigation Code, including guidelines to assist investigators in the implementation of the Code, to prevent similar accidents occurring again in the future. In this paper, a process of the human factors investigation is proposed to provide investigators with a guide for determining the occurrence sequence of marine accidents, to identify and classify human error-inducing underlying factors, and to develop safety actions that can manage the risk of marine accidents. Also, an application of these investigation procedures to a collision accident is provided as a case study This is done to verify the applicability of the proposed human factors investigation procedures. The proposed human factors investigation process provides a systematic approach and consists of 3 steps: 'Step 1: collect data & determine occurrence sequence' using the SHEL model and the cognitive process model; 'Step 2: identify and classify underlying human factors' using the Maritime-Human Factor Analysis and Classification System (M-HFACS) model; and 'Step 3: develop safety actions,' using the causal chains. The case study shows that the proposed human factors investigation process is capable of identifying the underlying factors and indeveloping safety actions to prevent similar accidents from occurring.

A Study on the Method for Field Investigation with Vehicle-Based Mobile Mapping System (차량 MMS를 이용한 현지 지리조사 수행 방안 연구)

  • Hwang, Jin-Sang;Yun, Hong-Sic;Jeong, Tae-Jun;Yi, Gwang-Jae;Gang, In-Gu
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2010.04a
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    • pp.113-115
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    • 2010
  • We studied the methods to utilize vehicle-based mobile mapping system for field investigation work of digital map generation process. Map layers which should be checked by field investigation were analyzed to find the possibility of being checked with data from vehicle-based mobile mapping system. Also new process for digital map generation were suggested to adopt field investigation by vehicle-based mobile mapping system. We performed field investigation work on the Kangneung area by vehicle-based mobile mapping on a trial bases and compared the results with a results from usual field investigation method.

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Experimental Investigation of the Steel Cord Straightening during the Stranding Process (스틸코드 연선 시 주요공정에 따른 교정효과의 실험적 관찰)

  • Bae, G.H.;Lee, J.S.;Huh, H.;Lee, J.W.;Lee, B.H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.05a
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    • pp.286-289
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    • 2009
  • This paper deals with the experimental investigation of the steel cord straightening during the stranding process. The over-twisting and roller straightening process are essential to improve the product quality during the stranding process. To investigate the effectiveness of two processes, four experimental cases are constructed according to the use of an over-twister and two roller straighteners. Three assessment items, such as the residual torsion, the arc-height and the preforming ratio, are measured in each experimental case for the quantitative evaluation of a steel cord. The steel cord shape is also measured to investigate the variation of the straightness efficiently after passing through each process. Finally, the effectiveness of the over-twisting and the roller straightening process is explained based on the experimental results.

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Development of Work Process on Natural Disaster Damage Investigation using Smartphones (스마트폰 기반 자연재난 피해조사 업무 프로세스 개발)

  • Choi, Woong Jung;Cho, Jae Woong
    • Journal of Korean Society of Disaster and Security
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    • v.5 no.2
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    • pp.1-10
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    • 2012
  • Natural disasters are occurring frequently due to typhoon and flood. Especially, damage scales are increasing these days because of climate change. When natural disasters occur, civil engineering officers investigate them for the recovery. If public facilities are damaged, the disaster damage investigation must be finished within 7days. Currently, natural disaster damage investigation is done on two levels, field investigation and data input into NDMS. However, having those two overlapped most of the time, and we must do subsidiary works things to register field investigation data into system. Work efficiency is decreased due to repetition of additional work. So, many civil engineering officers indicated problems such as lack of manpower and time. In this study, We developed work process on natural disaster damage investigation that involves using smart phone to solve problems such as shortage of time and manpower.

A Study on the Temperature Distribution and Deformation of Case in Shrinkage Fit Process(II) - Deformation Measurement and Deformation Analysis Model - (열박음 공정이 케이스의 온도분포 및 변형에 미치는 영향(II) - 변형 계측 및 변형 해석 모델 정립 -)

  • 장경복;정진우;강성수;최규원;박찬우;조상명
    • Journal of Welding and Joining
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    • v.19 no.5
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    • pp.492-498
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    • 2001
  • In the previous study, temperature monitoring of case about shrinkage fit process was performed and heat transfer model was developed in detail by feedback and tuning among monitoring result, process investigation, and analysis result. The gap element in contact between case and core was effectively used in analysis model. In present study, following things are performed to solve deformation of case due to shrinkage fit process on the basis of previous result. Above all, mechanical material properties of case are measured by case specimen for deformation analysis considering weldment of case. Deformation of case before and after shrinkage fit process is measured, too. Three dimensional deformation model is developed by the comparison and inspection between these experimental data and analysis results. Deformation analysis is simulated with the result of heat transfer analysis, in other words, non-coupled analysis is used. Finally the countermeasure for deformation is brought up through those.

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A Study on the Analysis of Chemical Leakage Accidents Using CFD Simulation (CFD 시뮬레이션을 활용한 화학물질 누출사고 분석에 관한 연구)

  • Su-Bin An;Chang-Bong Jang;Kyung-Su Lee;Hye-Ok Kwon
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.33 no.3
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    • pp.346-354
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    • 2023
  • Objectives: Chemical accidents cause extensive human and environmental damage. Therefore, it is important to prepare measures to prevent their recurrence and minimize future damage through accident investigation. To this end, it is necessary to identify the accident occurrence process and analyze the extent of damage. In this study, the development process and damage range of actual chemical leakage accidents were analyzed using CFD. Methods: For application to actual chemical leakage accidents using FLACS codes specialized for chemical dispersion simulation among CFD codes, release rate calculation and 3D geometry were created, and scenarios for simulation were derived. Results: The development process of the accident and the dispersion behavior of materials were analyzed considering the influencing factors at the time of the accident. In addition, to confirm the validity of the results, we compared the results of the actual damage impact investigation and the simulation analysis results. As a result, both showed similar damage impact ranges. Conclusions: The FLACS code allows the detailed analysis of the simulated dispersion process and concentration of substances similar to real ones. Therefore, it is judged that the analysis method using CFD simulation can be usefully applied as a chemical accident investigation technique.