• Title/Summary/Keyword: leakage checking

Search Result 47, Processing Time 0.029 seconds

Thermal Stress Analysis of the Heat Generation for Mass Concrete Considering Creep Effect (크리이프를 고려한 매스콘크리트의 수화열에 대한 온도응력 해석)

  • Kim, Jin Keun;Lee, Jong Dae
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.14 no.4
    • /
    • pp.771-781
    • /
    • 1994
  • The heat generation of cement causes the internal temperature rise and volume change at early age, particulary in massive concrete structures. As the results of the temperature rise and restraint conditions, the thermal stress may induce cracks in concrete. Therefore, the prediction of the thermal stress is very important in the design and construction in order to control the cracks developed in mass concrete. In case of young concrete, creep effect by the temperature load is larger than that of old concrete. Thus, the effect of creep must be considered for checking the cracks, serviceability, durability and leakage. This paper is concentrated on the development of a finite element program which is capable of simulating the temperature history and the thermal stress considering creep and the modified elastic modulus due to inner temperature change and maturity. The analytical results in the inner parts highest important to control cracks are in good agreement with experimental data. Therefore this study may provide available method to control the cracks.

  • PDF

A Study of Checking the Job History of External USB Media (외장형 USB 매체의 작업이력 점검 방법에 관한 연구)

  • Lee, Seongjae;Noh, Bongnam
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.27 no.4
    • /
    • pp.753-761
    • /
    • 2017
  • Recently, malicious code infiltration and leakage of confidential documents using external USB medium are frequently occurring in each field. We investigate the media to investigate incidents using external USB media, but there are many difficulties in that they can be lost or damaged. Ultimately, in order to investigate cases of external USB media, it is necessary to conduct a direct analysis of the external USB media as well as the system to which the media is connected. This paper describes an analysis of the artifacts of Windows systems to which external USB media is connected, and how to check the job history on the media. Therefore, it is expected that the system can be used to analyze the job history of the USB medium even if the external USB medium is not secured.

Car Engine Sealing Inspection System Based on Analysis of Difference Image (차영상 분석 기반의 자동차 엔진 실링상태 검사 시스템)

  • Choi, Sang-Bok;Ban, Sang-Woo;Kim, Ki-Taeg
    • Journal of Korea Multimedia Society
    • /
    • v.14 no.3
    • /
    • pp.356-367
    • /
    • 2011
  • In this paper, we proposed a new car engine sealing inspection system based on image processing and understanding. The car engine sealing inspection plays very important role for protecting leakage caused by inappropriate sealing, which is a crucial point for productivity of car engines. The proposed inspection system has been aimed to enhance the previously proposed sealing inspection systems based on image processing, which have high computation complexity and low performance for correctly inspecting some contamination by oil with similar color with that of sealing. Moreover, the previously proposed system has a difficulty in installing the camera system on the sealing machine. The proposed system considers a difference of images before and after sealing obtained from one static camera. By utilizing a difference of images, the proposed system shows very robust performance using a proposed simple depth checking algorithm for some contamination cases by oil with similar color with that of sealing and the total inspection system is simple and cheap to implement. According to the experiments conducted in a real car product line, the proposed inspection system shows better inspection performance and needs smaller implementation cost than three other previously proposed system working in current car sealing inspection systems.

An Efficient Water Pressure Measurement System of the Water Pipes using IoT (IoT를 이용한 상수도관의 효율적인 수압 측정 시스템)

  • Lee, Jae-soo;Choi, In-ho;Hong, Kwon-eui;Choi, Hak-yun;Roh, Hee-jung;Ahn, Jeong-keun
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.17 no.1
    • /
    • pp.114-122
    • /
    • 2018
  • In this paper, we propose new water pressure measurement system to measure the water pressure of water pipe laid underground beneath the manhole efficiently. For this purpose, we installed water pressure sensor(IoT) which has built-in bluetooth module at valve of water pipe. The proposed system can be managed through collected data which measured at sensor and then transmitted to smart phone through bluetooth connectivity and re-transmitted to server on this system. By checking out water pressure data stored in server from remote location, the persons in charge can confirm the leakage of water pipe or propriety of water pressure in management area. By this procedure, they can detect the existence of condition of water pipe and manage water pressure of water pipe efficiently.

Design concept investigation for corner protection of LNG storage tank by ASME section VIII, Div. 2 (ASME section VIII div. 2에 따른 LNG저장탱크 코너프로텍션의 설계개념 고찰)

  • Kim Hyoungsik;Hong Seongho;Seo Heungseok;Yang Youngchul
    • Journal of the Korean Institute of Gas
    • /
    • v.5 no.3 s.15
    • /
    • pp.73-79
    • /
    • 2001
  • The corner protection which is consist of insulation and $9\%$ nickel liner is designed to mitigate the high hoop tension at the corner of LNG storage tank by LNG leakage. So the design loads depend on thermal and liquid pressure from leaked LNG In this paper design conditions are suggested as operating, major and minor leak conditions. And in order to check integrity of comer protection for the design conditions by appendix 4 in ASME section VIII div.2, acceptability checking process that have stress categorization and finite element analysis is explained.

  • PDF

Verification of a Function-based Security Authentication Protocol for Implantable Medical Devices (함수 기반의 체내 삽입장치용 보안 인증프로토콜 검증)

  • Bae, WooSik;Han, KunHee
    • Journal of Digital Convergence
    • /
    • v.12 no.5
    • /
    • pp.249-254
    • /
    • 2014
  • Recent advancement of USN technology has lent itself to the evolving communication technology for implantable devices in the field of medical service. The wireless transmission section for communication between implantable medical devices and patients is a cause of concern over invasion of privacy, resulting from external attackers' hacking and thus leakage of private medical information. In addition, any attempt to manipulate patients' medical information could end up in serious medical issues. The present study proposes an authentication protocol safe against intruders' attacks when RFID/USN technology is applied to implantable medical devices. Being safe against spoofing, information exposure and eavesdropping attacks, the proposed protocol is based on hash-function operation and adopts session keys and random numbers to prevent re-encryption. This paper verifies the security of the proposed protocol using the formal verification tool, Casper/FDR.

A Study on the User Identification and Authentication in the Smart Mirror in Private (사적공간의 스마트미러에서 사용자 식별 및 인증 기법 연구)

  • Mun, Hyung-Jin
    • Journal of Convergence for Information Technology
    • /
    • v.9 no.7
    • /
    • pp.100-105
    • /
    • 2019
  • As IoT Technology develops and Era of Hyperconnectivity comes, various kinds of customized services became available. As a next-generation display, a smart mirror accesses multimedia devices and provides various services, so it can serve as a social learning tool for the children and the old ones, as well as adults who need information. Smart Mirror must be able to identify users for individualized services. However, since the Smart Mirror is an easily accessible device, there is a possibility that information such as an individual's pattern and habit stored in the smart mirror may be exposed to the outside. Also, the other possibility of leakage of personal location information is through personal schedule or appointment stored in the smart mirror, and another possibility that privacy can be violated is through checking the health state via personal photographs. In this research, we propose a system that identify users by the information the users registered about their physique just like their face, one that provides individually customized service to users after identifying them, and one which provides minimal information and service for unauthenticated users.

A Study on Event Log Correlation Analysis for Control System Threat Analysis (제어시스템 위협분석을 위한 Event Log 상관분석에 관한 연구)

  • Kim, Jongmin;Kim, Minsu;Lee, DongHwi
    • Convergence Security Journal
    • /
    • v.17 no.5
    • /
    • pp.35-40
    • /
    • 2017
  • The control system can have such threats as information leakage and falsification through various routes due to communications network fusion with public network. As the issues about security and the infringe cases by new attack methods are diversified recently, with the security system that makes information data database by simply blocking and checking it is difficult to cope with new types of threats. It is also difficult to respond security threats by insiders who have security access authority with the existing security equipment. To respond the threats by insiders, it is necessary to collect and analyze Event Log occurring in the internal system realtime. Therefore, this study could find out whether there is correlation of the elements among Event Logs through correlation analysis based on Event Logs that occur real time in the control system, and based on the analysis result, the study is expected to contribute to studies in this field.

Radiation safety for pain physicians: principles and recommendations

  • Park, Sewon;Kim, Minjung;Kim, Jae Hun
    • The Korean Journal of Pain
    • /
    • v.35 no.2
    • /
    • pp.129-139
    • /
    • 2022
  • C-arm fluoroscopy is a useful tool for interventional pain management. However, with the increasing use of C-arm fluoroscopy, the risk of accumulated radiation exposure is a significant concern for pain physicians. Therefore, efforts are needed to reduce radiation exposure. There are three types of radiation exposure sources: (1) the primary X-ray beam, (2) scattered radiation, and (3) leakage from the X-ray tube. The major radiation exposure risk for most medical staff members is scattered radiation, the amount of which is affected by many factors. Pain physicians can reduce their radiation exposure by use of several effective methods, which utilize the following main principles: reducing the exposure time, increasing the distance from the radiation source, and radiation shielding. Some methods reduce not only the pain physician's but also the patient's radiation exposure. Taking images with collimation and minimal use of magnification are ways to reduce the intensity of the primary X-ray beam and the amount of scattered radiation. It is also important to carefully select the C-arm fluoroscopy mode, such as pulsed mode or low-dose mode, for ensuring the physician's and patient's radiation safety. Pain physicians should practice these principles and also be aware of the annual permissible radiation dose as well as checking their radiation exposure. This article aimed to review the literature on radiation safety in relation to C-arm fluoroscopy and provide recommendations to pain physicians during C-arm fluoroscopy-guided interventional pain management.

Development of an Integrated Quarantine System Using Thermographic Cameras (열화상 카메라를 이용한 통합 방역 시스템 개발)

  • Jung, Bum-Jin;Lee, Jung-Im;Seo, Gwang-Deok;Jeong, Kyung-Ok
    • Journal of the Korea Safety Management & Science
    • /
    • v.24 no.1
    • /
    • pp.31-38
    • /
    • 2022
  • The most common symptoms of COVID-19 are high fever, cough, headache, and fever. These symptoms may vary from person to person, but checking for "fever" is the government's most basic measure. To confirm this, many facilities use thermographic cameras. Since the previously developed thermographic camera measures body temperature one by one, it takes a lot of time to measure body temperature in places where many people enter and exit, such as multi-use facilities. In order to prevent malfunctions and errors and to prevent sensitive personal information collection, this research team attempted to develop a facial recognition thermographic camera. The purpose of this study is to compensate for the shortcomings of existing thermographic cameras with disaster safety IoT integrated solution products and to provide quarantine systems using advanced facial recognition technologies. In addition, the captured image information should be protected as personal sensitive information, and a recent leak to China occurred. In order to prevent another case of personal information leakage, it is urgent to develop a thermographic camera that reflects this part. The thermal imaging camera system based on facial recognition technology developed in this study received two patents and one application as of January 2022. In the COVID-19 infectious disease disaster, 'quarantine' is an essential element that must be done at the preventive stage. Therefore, we hope that this development will be useful in the quarantine management field.