• Title/Summary/Keyword: system uncertainty

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Research on the Use of Pseudonym Data - Focusing on Technical Processing Methods and Corporate Utilization Directions - (가명 데이터 활용연구 - 기술적 처리방법 및 기업의 활용방향을 중심으로 -)

  • Kim, Jung-Sun
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.30 no.2
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    • pp.253-261
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    • 2020
  • This study examines the technologies and application processes related to the use of pseudonym data of companies after the passage of the Data 3 Act to activate the data economy in earnest, and what companies should prepare to use pseudonym data and what will happen in the process It was intended to contribute to the elimination of uncertainty. In the future, companies will need to extend the information security management system from the perspective of the existing IT system to manage and control data privacy protection and management from a third party provisioning perspective. In addition, proper pseudonym data use control should be implemented even in the data use environment utilized by internal users. The economic effect of market change and heterogeneous data combination due to the use of pseudonymized data will be very large, and standards for appropriate non-identification measures and risk assessment criteria for data utilization and transaction activation should be prepared in a short time.

Sliding-Mode Control of Container Cranes (컨테이너크레인 시스템의 슬라이딩모드제어)

  • Lee Suk-Jae;Park Hahn;Hong Keum-Shik
    • Journal of Navigation and Port Research
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    • v.29 no.8 s.104
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    • pp.747-753
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    • 2005
  • In this paper, as an anti-sway control strategy of container cranes, we investigate a variable structure control in which the moving load follows a given trajectory, whereas both the trolley and hoist controllers achieve their positioning problems. It is crucial, in an automated container terminal, that collisions should be avoided during the transference of containers from one place to another. It is also necessary, in the case of a quay crane, to select suitable loading and unloading trajectories of containers, so that possible collisions with surrounding obstacles are avoided. After a brief introduction of the mathematical model, a robust control scheme (i.e., a second-order sliding mode control that guarantees a fast and precise transference and a suppression of the resulted swing) is presented. Despite model uncertainties and unmodeled actuators dynamics, the swing suppression from the given trajectory is obtained by constraining the system motion on suitable sliding surfaces, which include both the desired path and the swing angle. The proposed controller has been tested with a laboratory-size pilot crane. Experimental results are provided.

A Method for Simultaneous Measurement of Air Kerma, Half Value Layer and Tube Potential in Quality Control Procedure of Diagnostic x ray units

  • Katoh, Tsuguhisa;Saitoh, Hidetoshi;Ohtani, Hiroki;Negishi, Tooru;Myojoyama, Atsushi;Ohno, Yuusuke;Sasaki, Takehito
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2002.09a
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    • pp.294-297
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    • 2002
  • For the quality control procedure of diagnostic x ray units, a method for simultaneous measurement of air kerma, half value layer and tube potential was developed utilizing a computed radiography system for intraoral radiography and film badge case. The response of average pixel values under the windows were calibrated by x rays generated at tube potentials from 40 to 140 kV with filtration from 1.5 to 3.7 mmAl. The calibration curves for half value layer and tube potential were derived as functions of attenuation factors by the 1.4 mmAl filter and the 0.2 mmCu filter. The energy dependency of the open window response was corrected by the calibration factor as a function of the attenuation factor by the 1.4 mmAl filter. The uncertainty of the estimated half value layer, tube potential and air kerma were 0.2 mmAl, 3.6 % and 5 %, respectively. It was thus suggested that this system could be applied to quality control program to detect the variation of working condition of x ray units in clinical use.

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Petri nets modeling and dynamic scheduling for the back-end line in semiconductor manufacturing (반도체 후공정 라인의 페트리 네트 모델링과 동적 스케쥴링)

  • Jang, Seok-Ho;Hwang, U-Guk;Park, Seung-Gyu;Go, Taek-Beom;Gu, Yeong-Mo;U, Gwang-Bang
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.6
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    • pp.724-733
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    • 1999
  • An effective method of system modeling and dynamic scheduling for the back-end line of semiconductor manufacturing is proposed. The virtual factory, describing semiconductor manufacturing line, is designed in detail, and then a Petri net model simulator is developed for operation and control of the modular cells of the virtual factory. The petri net model is a colored timed Petri nets (CTPNs). The simulator will be utilized to analyze and evaluate various dynamic status and operatons of manufacturing environments. The dynamic schedulaer has a hierarchical structure with the higher for planning level and the lower for dynamic scheduling level. The genetic algorithm is applied to extract optimal conditions of the scheduling algorithm. The proposed dynamic scheduling is able to realize the semiconductor manufacturing environments for the diversity of products, the variety of orders by many customers, the flexibility of order change by changing market conditions, the complexity of manufacturing processes, and the uncertainty of manufacturing resources. The proposed method of dynamic scheduling is more effective and useful in dealing with such recent pressing requirements including on-time delivery, quick response, and flexibility.

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Long-Term Perspectives on Social Changes and Issues in Social Insurance (장기적 관점에서 본 사회변화와 사회보험의 과제)

  • Kim, Jin-Soo
    • Korean Journal of Social Welfare
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    • v.46
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    • pp.37-59
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    • 2001
  • This paper investigates the long-term social changes and the emerging issues in social insurance that such changes will entail, It does not attempt to resolve the conflict between neo-liberal reforms and neo-corporalist reforms. Nor does it confine itself to proposing the options to secure the financial stability of social insurance schemes. The aim of this paper lies in anticipating various problems that result from social development, analyzing the impacts of these problems on social insurance schemes, and delineating the solutions to these problems. This paper is comprised of three parts. First, it describes the expected long-term changes in society and the ensuing problems. Second, it asks whether these problems can be solved with increased public expenditures. For this purpose, an analysis of the trend in the expenditures by welfare states is attempted. Third, it summarizes the issues in social insurance and presents the possible solutions to the problems. In the chapter that deals with social changes and social problems, various aspects are reviewed, including the globalization process, the development of It industries, the uncertainty in the classification of incomes, the widening gap in earnings due to the bio-economy, and the relation between social insurance schemes and the tax system. It is concluded that there are limits to the role that increased public expenditures can play to solve the social problems. This paper argues for a structural change in the social insurance system. In every social insurance scheme, the state should foe-us its effect on the provision of basic protection against social risks for the whole population. At the same time, the state should improve the financial stability of the scheme and avoid large-scale deficits.

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Wind Tunnel Test for the Propeller Performance of the High Altitude UAV (고고도 무인기용 프로펠러 성능특성 풍동시험)

  • Cho, Teahwan;Kim, Yangwon;Park, Donghun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.46 no.3
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    • pp.189-196
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    • 2018
  • Propeller performance measurement system for high altitude UAV was designed and applied to the wind tunnel test for 2 propeller models with a diameter around 1 m. Mechanical power of the propeller was directly measured by using the torque sensor installed on the rotating axis. The thrust of whole operation body including the propeller was measured by thrust road cell. The guide rail system was suggested to reduce the weight influence of operation body on the thrust road cell. The influence of each measured variables on the aerodynamic coefficients was studied with the repeatability and uncertainty analysis. This analysis result shows that the accuracies of the road cell and the wind velocity were major factors for the thrust coefficient. Propeller performance with typical RPM was measured with various wind speeds and the test results was summarized by performance coefficients for 5 different RPM.

The Main Contents and Characteristics of the Draft Convention on Electronic Contracting (전자계약에 관한 국제협약 초안의 주요내용과 특징에 관한 연구)

  • Choi, Seok-Beom;Park, Chong-Suk;Jung, Jae-Woo
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.20
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    • pp.467-493
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    • 2003
  • There are situations in e-commerce that are altogether new and to which the existing rules cannot apply. The uncertainty and business risk is too high for trading partners to deal with certainty. Therefore existing law must be changed to e-commerce law so that it provides certainty and enforceability in the e-commerce. Legal rules applying to the commerce and international commerce, in particular, contracts, proper law, jurisdiction and so on, have improved with time and experience. It has been found that the problems arising in the context of e-contracting were due to the absence of experience in electronic contracting and an absence of knowledge on how best to solve the problems. Thus, UNCITRAL Working Group on Electronic Commerce held an extensive discussion on issues related to electronic contracting and prepared and revised the Preliminary Draft Convention on International Contracts Concluded or Evidenced by Data Message from the thirty-ninth session in 2002 and prepared the Draft Convention from forty-first session which applies to international contracts concluded or evidenced by means of data messages. An electronic contract is concluded when the acceptance of an offer becomes effective, and an offer becomes effective when it is received by the offeree, and an acceptance of an offer becomes effective when the indication of assent is received by the offeror according to this Convention. Electronic contract may be concluded by the interaction of an automated computer system and natural person or by the interaction of automated computer systems, and a contract formed by a natural person that accesses an automated computer system of another person has no legal effect in case the neutral person made a material error in a data message. The purpose of this paper is to raise the understanding of the Convention on the Electronic Contracting by studying the contents of Draft Convention on Electronic Contracting and comparing Draft Convention with preliminary Draft Convention and finding the difference, characteristics and problem.

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Study on applying to Hazard Classification Criteria of Chemicals subject to Material Safety Data Sheets (물질안전보건자료 대상물질의 유해성 분류기준 적용 연구)

  • Lee, Hye Jin;Lee, Naroo;Lee, In Seop
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.30 no.3
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    • pp.280-291
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    • 2020
  • Objectives: Hazard classification is a controversial issue in the new MSDS system in which chemical companies have to prepare and submit MSDS for chemicals that they manufacture or import to the competent authorities according to the amended Occupational Safety and Health Act. The aim of this study is to suggest how to apply and manage harmonized hazard classification criteria and results by investigating current hazard classification systems and trends. Methods: The domestic issues about different hazard classification criteria and results were investigated by reviewing the literature and business outcomes regarding KOSHA. We also checked official and unofficial reports from the UN to understand international discussion about the topic. Chemical hazard classification results from agencies providing chemical information were analyzed to compare a harmonized rate between classifications. Furthermore, a field survey of a few chemical companies was conducted. Results: Under the related competent authorities, an integrated standard proposal was developed to harmonize the domestic hazard classification criteria. Although harmonized chemical information is strongly needed, we recognized the uncertainty and difficulty of harmonized hazard classification from the UN global list project review. In practice the harmonization rate of the classification was generally low between the classification in KOSHA, MoE, and EU CLP. Among hazard classes, health hazards largely led the disharmony. The field survey revealed a change of perception that the main body of chemical information production is manufacturers. Approaches and solutions about hazard classification issues differed depending on business size, types of chemical handling, and other factors. Conclusions: We proposed reasonable ways by time and step to apply hazard classification in the new MSDS system. Chemical manufacturers should make and offer chemical information including responsible hazard classifications. The government should primarily accept these classifications, evaluate them by priority, and support or supervise workplaces in order to communicate reliable chemical information.

Performance Appraisal of Total Maximum Daily Loads: Performance on Development/Reduction Plan and Water Quality Status of Unit Watershed (수질오염총량관리제의 성과평가: 개발/삭감계획의 이행실적 및 단위유역의 수질 현황)

  • Park, Jae Hong;Park, Jun Dae;Rhew, Doug Hee;Jung, Dong Il
    • Journal of Korean Society on Water Environment
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    • v.25 no.4
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    • pp.481-493
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    • 2009
  • This study was conducted to performance appraisal of Total Maximum Daily Loads (TMDLs), especially in terms of performance on development & reduction plan and water quality status of unit watershed. Because load allocations for pollution sources were predicted redundantly by uncertainty of prediction, TMDLs master plan has been frequently changed to acquire load allocation for local development. Therefore, It need to be developed more resonable prediction techniques of water pollution sources to preventing the frequent change. It is suggested that the reduction amount have to be distributed properly during the planning period. In other words, it has not to be concentrated on the specific year (especially final year of the planning period). The reason why, if the reduction amount concentrate on the final year of the planning period, allotment loading amount could not be achieved in some cases (e.g., insufficiency of budget, extension of construction duration). If the development plan was developed including uncertain developments, it is necessary to be developed reduction plan considered with them. However, some of the plans in the reduction plan could not be accomplished in some case. Because, it is not considered financial abilities of local governments. Consequently, development plan must be accomplished to avoid uncertain developments, and to consider financial assistance to support the implementation of effective plan. Water quality has been improved in many unit watersheds due to the TMDLs, especially in geum river and yeongsang/seomjin river.

A Study of Optical Characteristics for Biodiesel and Diesel Smoke Particles and Measuring their Dimensionless Light Extinction Constants (바이오디젤과 디젤 연기입자의 광학특성 및 무차원 광소멸계수 측정에 관한 연구)

  • Choi, Seuk-Cheun;Jang, Yeong-Seok;Park, Seul-Hyun;Kim, Youn-Kyu
    • Fire Science and Engineering
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    • v.30 no.1
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    • pp.37-42
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    • 2016
  • The dimensionless extinction constants of smoke particles produced from burning of soy methyl ester (B100) biodiesel and ultra low sulfur diesel (ULSD) fuels were measured. To this end, optical measurements of smoke volume fraction with the aid of a He-Ne laser at 633 nm were compared to the simultaneous gravimetric measurements. The average value of measured dimensionless extinction constants at 633 nm was 11.8 for biodiesel smoke particles and 11.1 for diesel smoke particles, respectively whose values are very comparable withing the range of measurement uncertainty (${\pm}10.1%$). The analysis of Raman spectroscopy revealed that overall characteristics of light extinction between particles produced from each fuel may differ from each other.