• Title/Summary/Keyword: Safety-critical systems

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Value and Theoretical Limitations in Regional Innovation Systems (지역혁신체제론의 전개과정에서 나타난 함축된 가치와 이론적 한계)

  • Nam, Jae-Geol
    • Journal of the Korean association of regional geographers
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    • v.13 no.3
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    • pp.254-270
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    • 2007
  • The concept of Regional Innovation System(RIS) has been developed with the accumulation of empirical research and the reflection on the political and economic environments. It is widely used as a nonnative concept to tackle the problem of regional disparities by enhancing regional innovative development. However, it seems that there is a gap between the theoretical framework of RIS and its actual application in reality. This paper attempts to extend our knowledge about RIS with critical viewpoint. It tries to unravel some values that RIS implies and its theoretical limitations, which were found through the evolution of RIS such as its theoretical roots, the development of its research and policy; and an example of its building in practice.

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Hazardous event analysis in drinking water production using aquifer storage transfer and recovery (대수층 저장·이동 및 회수에 의한 음용수 생산과정에서의 위해사건분석)

  • Lee, Sang-Il;Ji, Hyon-Wook
    • Journal of Korean Society of Water and Wastewater
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    • v.29 no.1
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    • pp.23-31
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    • 2015
  • Aquifer storage transfer and recovery (ASTR) is a type of managed aquifer recharge which entails injecting water into a storage well and recovering it from a different well. It has effects of natural purification when injected water passes through aquifer medium, and can be a good way of supplying water especially in a region with poor surface water quality. This study is about an on-going effort to introduce ASTR as a solution to source water problems in coastal areas. A pilot study is being conducted in the delta of the Nakdong River. A proactive management system is incorporated to ensure the water qulity in the process of drinking water process. The system is based on the Hazard Analysis and Critical Control Point (HACCP) which is a tool originated from the food industry in order to assess hazards and establish control systems for the safety of food product. In this paper, we analyze hazardous events which can occur in the entire water supply system using ASTR as a first step to the incorporation of HACCP to drinking water production process.

Hydrogen Effect Assessment of Fuel Supply Systems for Hydrogen Blended Natural Gas Vehicle (수소-천연가스 혼합연료 차량 연료 공급시스템 수소영향 평가)

  • Kang, SeungKyu;Kim, SangRyul
    • Journal of Energy Engineering
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    • v.26 no.4
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    • pp.1-6
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    • 2017
  • This study evaluated hydrogen effect of metal and non-metallic materials used in the hydrogen blended natural gas vehicle. Hydrogen penetrated concentration of 34Cr-Mo steel(850MPa tensile strength) for winter driving conditions was measured 0.0018ppm and summer driving conditions was 5.3ppm. The critical hydrogen concentration of high strength metal used in this study was measured 1.03ppm by CLT. Therefore, 34CrMo steel cas cause problems in the 30% HCNG(25MPa) environment. In case of the test for non-metallic materials, all materials met the criteria of the gas resistance test, but Fluorocarbon Rubber material had a significant change in the volume. So if it is used, extra care is needed.

Introduction to the Intelligent Excavating System: Concept design of Intuitive Operator Control Unit (지능형 굴삭시스템 개발: 직감형 원격제어 시스템 개념설계)

  • Yu, Byung-Gab;Lee, Seung-Yeol;Lee, Sang-Ho;Yu, Seok-Jong;Yu, Bo-Hyun;Jang, June-Hyun;Han, Chang-Soo
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2007.04a
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    • pp.68-73
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    • 2007
  • Civil engineering construction work has always been accompanied by a high proportion of tasks that are either dangerous or unpleasant or both. Enhancing the general working environment and boosting safety levels are critical issues for the industry. In addition to that, the industry has been slow to utilize automation & robot technology, and there is substantial scope for the use of technology th boost efficiency, cut costs and improve quality levels in construction. In a bid to address this issue, Ministry of Construction & Transportation launched a five-year project in 2003 entitled Development of Intelligent Excavating System. The aim of the project is to use telecommunications and robotics technology to minimize inefficiencies and eliminate the dangerous and unpleasant aspects of tile construction process through the development of specific applications such as IT-equipped construction machinery and advanced construction management systems. In this paper, the project introduces on the research and development content related to multi-disciplinary, a intuitive operator control unit(Robot Technology) included.

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Seismic response of geosynthetic reinforced retaining walls

  • Jesmani, Mehrab;Kamalzare, Mehrad;Sarbandi, Babak Bahrami
    • Geomechanics and Engineering
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    • v.10 no.5
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    • pp.635-655
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    • 2016
  • The effects of reinforcement on the horizontal and vertical deformations of geosynthetic reinforced retaining walls are investigated under a well-known seismic load (San Jose earthquake, 1955). Retaining walls are designed with internal and external stability (with appropriate factor of safety) and deformation is chosen as the main parameter for describing the wall behavior under seismic load. Retaining walls with various heights (6, 8, 10, 12 and 14 meter) are optimized for geosynthetics arrangement, and modeled with a finite element method. The stress-strain behavior of the walls under a well-known loading type, which has been used by many previous researchers, is investigated. A comparison is made between the reinforced and non-reinforced systems to evaluate the effect of reinforcement on decreasing the deformation of the retaining walls. The results show that the reinforcement system significantly controls the deformation of the top and middle of the retaining walls, which are the critical points under dynamic loading. It is shown that the optimized reinforcement system in retaining walls under the studied seismic loading could decrease horizontal and vertical deformation up to 90% and 40% respectively.

Transformation of a Dynamic Load into an Equivalent Static Load and Shape Optimization of the Road Arm in Self-Propelled Howitzer (자주포 로드암 동하중의 상당 정하중으로의 변환 및 형상최적설계)

  • Choe, U-Seok;Gang, Sin-Cheon;Sin, Min-Jae;Park, Gyeong-Jin
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.12
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    • pp.3767-3781
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    • 1996
  • Generally, dynamic loads are applied to real structures. Since the analysis with the dynamic load is extremely difficult, static loads are utilized by proper conversions of the dynamic loads. The dynamic loads are usually converted ot static loads by safety foactors of experiences. However, it may increase weight and decrease reliability. In this study, a method is proposed for the conversion process. An equivalent static load is calculated ot generate a same maximum displacement. The method is verified through numerical tests on a spring-mass systems of one and multi degrees-of freedom. It has been found that the duration time of the loads and the natural frequencies of the structures are critical in the conversion process. A road arem is a self-propelled howizer is selected for the application of the proposed method. The shape of the road arm is optimized under the converted static loads.

A study on the improvement of BCM industry through legal systems (BCM(재해경감활동관리)산업 활성화를 위한 법·제도 개선 방안 연구)

  • Han, Jong-U
    • Disaster and Security
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    • v.5 no.1
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    • pp.93-100
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    • 2015
  • Although many years passed since 'The Legislative bill on the support of voluntary activities of enterprises for disaster reduction'(hereinafter referred to as 'enterprise disaster reduction act') has been first enacted in 2007, BCMS is still not activated in our society. In contrast, after 911 Terror, importance of BCM is getting magnified and standardization research & institutionalization i s a lso proceeding i all over world. Lately, Disaster preventing activities is urgently needed like the sinking of 'Sewol ferry'. So the purpose of this paper is proposed for establishment of 'BCMS' and activation of the certificate system for Best-Run Business by analyzing the problem of 'enterprise disaster reduction act' and weak of activation as following. First, propel changing the policy of self-regulated participation to mandatory about the certificate system for Best-Run Business from public entity to government ministry and it is able to activate by propelling demo business of the certificate system for Best-Run Business. Second, public entity that has been given the certificate system for Best-Run Business by affiliating with Disaster Management Assessment of government management can be exempted from Disaster Management Assessment or those entity can arrange for connectivity acquisition method of 'Excellent rate'. Third, to publicize the activation of the law mentioned above, makes public entity r ecognizable by incorporating 'BCMS' into National safety management plan and establishment of National critical infrastructures security plan. Fourth, it should be reviewed to improving the related act regarding to inclusion of public organizations as well as private enterprises.

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Cables Condition Assessment for Circulating Water Pump & Condenser Extraction Pump (발전소 순환수 및 복수 계통 케이블 건전성 평가)

  • Ha, C.W.;Han, S.H.
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.614-615
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    • 2007
  • There are roughly a hundred types of cables in power plants. The distribution of circuits in a nuclear plant is comprised of 20% instrument cables, 61% control cables, 13% AC power cables, 1% DC power cables, and 5% communication lines. In the nuclear power plant, medium voltage cables are generally included in the scope of systems reviewed for safety and are included in a plant's maintenance program. Medium voltage cables provide power to many critical components in plants, including feed water pumps, circulating water pumps, and condensate pumps. Among these cables, high temperature sections of cables feeding electrical power to the circulating water pump and the condenser extraction pump were found. The evaluation for these cables is performed to find the maximum allowable current and temperature. The result shows that the load current flowed about 85% of the allowable current ampacity, and the temperature of conductor at full load current did not exceed the limited temperature. Therefore, existing cables for circulating water pump and condenser extraction pump system are going to be used during design life.

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5G Wireless Communication Technology for Non-Terrestrial Network (비지상네트워크를 위한 5G 무선통신 기술)

  • Kim, J.H.;Yoon, M.Y.;You, D.H.;Lee, M.S.
    • Electronics and Telecommunications Trends
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    • v.34 no.6
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    • pp.51-60
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    • 2019
  • As a way to further expand and enable the 5G ecosystem, the $3^{rd}$ Generation Partnership Project (3GPP) is considering the development of a 5G new radio (NR)-based non-terrestrial network (NTN). These NTNs are expected to provide ubiquitous 5G services to user's equipment (especially, in Internet of Things/machine-type communications (IoT/MTC) public safety, and critical communications) by extending service coverage to areas not covered by 5G terrestrial networks. To this end, this NTN is developing scenarios to provide 5G services using spaceborne vehicles, such as geosynchronous and low-Earth orbit satellites, and airborne vehicles, such as unmanned aircraft systems, including high-altitude pseudo-satellites. In addition, various technologies are being studied to satisfy new requirements not considered in 5G NR, such as long propagation delay time, large cell coverage, large Doppler effect, and base station movement. In this paper, we present the scenarios, requirements, technical issues and solutions, and standardization planning for NR-based NTN in 3GPP.

Security of Web Applications: Threats, Vulnerabilities, and Protection Methods

  • Mohammed, Asma;Alkhathami, Jamilah;Alsuwat, Hatim;Alsuwat, Emad
    • International Journal of Computer Science & Network Security
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    • v.21 no.8
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    • pp.167-176
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    • 2021
  • This is the world of computer science and innovations. In this modern era, every day new apps, webs and software are being introduced. As well as new apps and software are being introduced, similarly threats and vulnerable security matters are also increasing. Web apps are software that can be used by customers for numerous useful tasks, and because of the developer experience of good programming standards, web applications that can be used by an attacker also have multiple sides. Web applications Security is expected to protect the content of critical web and to ensure secure data transmission. Application safety must therefore be enforced across all infrastructure, including the web application itself, that supports the web applications. Many organizations currently have a type of web application protection scheme or attempt to build/develop, but the bulk of these schemes are incapable of generating value consistently and effectively, and therefore do not improve developers' attitude in building/designing stable Web applications. This article aims to analyze the attacks on the website and address security scanners of web applications to help us resolve web application security challenges.