• Title/Summary/Keyword: Electrical safety system

Search Result 1,366, Processing Time 0.027 seconds

Process Risk Assessment for a Batch Condensation Reaction of Polyester Resin using K-PSR Technique (K-PSR 기법을 활용한 회분식 폴리에스터 축합반응에서의 공정 위험성 평가 연구)

  • Park, Kyung-Min;Lee, Dong-Kyu;Lee, Haakil;Lee, Joon-Man;Ahn, Won-Sool
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.20 no.3
    • /
    • pp.35-42
    • /
    • 2019
  • Risk assessment and analysis for a medium-to-small sized chemical plant that manufactures a polyester resin by the process of batch-type condensation reaction was conducted using K-PSR technique which is one of the risk assessment methods used to implement the Process Safety Management System (PSM). K-PSR is a risk assessment technique developed by KOSHA to compensate for difficulties caused by the lack of infrastructure of medium-to-small sized chemical plants in the re-evaluation. To apply the K-PSR technique, the entire process of a selected chemical palnt was classified in two review sections, i.e., the condensation reaction process and the dilution/filtration process, and the potential risks of the process about these review sections were identified and classified based on the four guide-words (release, fire.explosion, process trouble, and injury). As the results of the research, refer to recommend of risk rating has been confirmed that non-destructive testing of old facilities and the preparation of LOTO procedures for the electrical equipments are necessary as specific measures to prevent the risk of release and fire.explosion. It was also shown that pressure gauges and thermometers should be installed on the hot-oil supply piping to minimize the process trouble, and exhausting hood should be installed to prevent potential injury.

무령왕릉보존에 있어서의 지질공학적 고찰

  • 서만철;최석원;구민호
    • Proceedings of the KSEEG Conference
    • /
    • 2001.05b
    • /
    • pp.42-63
    • /
    • 2001
  • The detail survey on the Songsanri tomb site including the Muryong royal tomb was carried out during the period from May 1 , 1996 to April 30, 1997. A quantitative analysis was tried to find changes of tomb itself since the excavation. Main subjects of the survey are to find out the cause of infiltration of rain water and groundwater into the tomb and the tomb site, monitoring of the movement of tomb structure and safety, removal method of the algae inside the tomb, and air controlling system to solve high humidity condition and dew inside the tomb. For these purposes, detail survery inside and outside the tombs using a electronic distance meter and small airplane, monitoring of temperature and humidity, geophysical exploration including electrical resistivity, geomagnetic, gravity and georadar methods, drilling, measurement of physical and chemical properties of drill core and measurement of groundwater permeability were conducted. We found that the center of the subsurface tomb and the center of soil mound on ground are different 4.5 meter and 5 meter for the 5th tomb and 7th tomb, respectively. The fact has caused unequal stress on the tomb structure. In the 7th tomb (the Muryong royal tomb), 435 bricks were broken out of 6025 bricks in 1972, but 1072 bricks are broken in 1996. The break rate has been increased about 250% for just 24 years. The break rate increased about 290% in the 6th tomb. The situation in 1996 is the result for just 24 years while the situation in 1972 was the result for about 1450 years. Status of breaking of bircks represents that a severe problem is undergoing. The eastern wall of the Muryong royal tomb is moving toward inside the tomb with the rate of 2.95 mm/myr in rainy season and 1.52 mm/myr in dry season. The frontal wall shows biggest movement in the 7th tomb having a rate of 2.05 mm/myr toward the passage way. The 6th tomb shows biggest movement among the three tombs having the rate of 7.44mm/myr and 3.61mm/myr toward east for the high break rate of bricks in the 6th tomb. Georadar section of the shallow soil layer represents several faults in the top soil layer of the 5th tomb and 7th tomb. Raninwater flew through faults tnto the tomb and nearby ground and high water content in nearby ground resulted in low resistance and high humidity inside tombs. High humidity inside tomb made a good condition for algae living with high temperature and moderate light source. The 6th tomb is most severe situation and the 7th tomb is the second in terms of algae living. Artificial change of the tomb environment since the excavation, infiltration of rain water and groundwater into the tombsite and bad drainage system had resulted in dangerous status for the tomb structure. Main cause for many problems including breaking of bricks, movement of tomb walls and algae living is infiltration of rainwater and groundwater into the tomb site. Therefore, protection of the tomb site from high water content should be carried out at first. Waterproofing method includes a cover system over the tomvsith using geotextile, clay layer and geomembrane and a deep trench which is 2 meter down to the base of the 5th tomb at the north of the tomv site. Decrease and balancing of soil weight above the tomb are also needed for the sfety of tomb structures. For the algae living inside tombs, we recommend to spray K101 which developed in this study on the surface of wall and then, exposure to ultraviolet light sources for 24 hours. Air controlling system should be changed to a constant temperature and humidity system for the 6th tomb and the 7th tomb. It seems to much better to place the system at frontal room and to ciculate cold air inside tombs to solve dew problem. Above mentioned preservation methods are suggested to give least changes to tomb site and to solve the most fundmental problems. Repairing should be planned in order and some special cares are needed for the safety of tombs in reparing work. Finally, a monitoring system measuring tilting of tomb walls, water content, groundwater level, temperature and humidity is required to monitor and to evaluate the repairing work.

  • PDF

Development of a Finger Tactile Stimulator Based on E-Prime Software (E-Prime에 기반한 손가락 촉각 자극기의 개발)

  • Kim, Hyung-Sik;Min, Yoon-Ki;Kim, Bo-Seong;Min, Byung-Chan;Yang, Jae-Woong;Lee, Su-Jeong;Choi, Mi-Hyun;Yi, Jeong-Han;Tack, Gye-Rae;Lee, Bong-Soo;Jun, Jae-Hoon;Chung, Soon-Cheol
    • Science of Emotion and Sensibility
    • /
    • v.13 no.4
    • /
    • pp.703-710
    • /
    • 2010
  • In this study, a tactile stimulator was developed to resolve some problems from the previous version of the system such as system configuration, inappropriate stimulation control and additional problems. The developed tactile stimulator consists of control unit, drive unit and vibrator unit. The control unit was controlled by E-Prime software to generate appropriate vibration pulses. The drive unit supplies enough energy to the vibrator to generate effective stimulation pulses. The vibrator unit consists of small coin type vibrator and velcro, and was made to be attached at the hand easily. The developed tactile stimulator was designed by small-size, light-weight, low-power, simple-fabrication, max 35 channels and little delay time from instruction signal of E-Prime software to vibrator. The duration and magnitude of stimulation was controlled by 10 grades and the problems concerning stimulation control were compensated by wideband frequency ranges. Additionally, the electrical safety was ensured by low voltage operation. Vibrator was made to be attached on finger as well as on any part of the subject. Since this tactile stimulator is developed based on E-Prime software which is widely used in cognitive science, it is believed that this stimulator be suitable for the wide application of cognitive science study.

  • PDF

Water Quality in a Drainage System Discharging Groundwater from Sangdae-ri Water Curtain Cultivation Area near Musimcheon Stream, Cheongju, Korea (무심천 인근 상대리 수막재배지에서 지하수 사용 후 배출되는 최종 배수로 물의 수질 특성)

  • Moon, Sang-Ho;Kim, Yongcheol;Hwang, Jeong
    • Economic and Environmental Geology
    • /
    • v.48 no.5
    • /
    • pp.409-420
    • /
    • 2015
  • The Sangdae-ri riverside around Musimcheon stream, flowing through Gadeok-myon of Cheongju City, is one of the representative strawberry fields employing water curtain cultivation (WCC) in Korea. In this area, annual groundwater use for WCC has been calculated by a few methods. On the assumption that all the water flowing through the final ditch may be mostly composed of groundwater, the discharge rate in it can be used as a good proxy for assessing the groundwater use. However, in the study area, the final ditch was set up in an unpaved state near and parallel to Musimcheon stream. Under such circumstances, the drainwater is likely to be influenced by infiltration and/or inflow of nearby stream. Hence, we examined whether or not stream water has influenced water flowing out through the final ditch in respect of ion concentrations or field parameters such as T, pH and electrical conductivity (EC) values. The period of measuring field parameters and sample collection was from February 2012 through February 2015. The drainwater in the final ditch did not show the average quality of groundwater, but similar quality of stream water in respect of pH, EC, ion contents and water type. From this, it is suggested that measuring the flow rate of the final ditch should not be directly used for assessing groundwater use in the study area. In addition, because of its sensitivity to ambient temperature, water temperature proved not to be appropriate for estimating the interaction between ditch and stream. For accuracy, additional methods will be needed to calculate mixing ratios between stream and ground water within drainage system.

KANO-TOPSIS Model for AI Based New Product Development: Focusing on the Case of Developing Voice Assistant System for Vehicles (KANO-TOPSIS 모델을 이용한 지능형 신제품 개발: 차량용 음성비서 시스템 개발 사례)

  • Yang, Sungmin;Tak, Junhyuk;Kwon, Donghwan;Chung, Doohee
    • Journal of Intelligence and Information Systems
    • /
    • v.28 no.1
    • /
    • pp.287-310
    • /
    • 2022
  • Companies' interest in developing AI-based intelligent new products is increasing. Recently, the main concern of companies is to innovate customer experience and create new values by developing new products through the effective use of Artificial intelligence technology. However, due to the nature of products based on radical technologies such as artificial intelligence, intelligent products differ from existing products and development methods, so it is clear that there is a limitation to applying the existing development methodology as it is. This study proposes a new research method based on KANO-TOPSIS for the successful development of AI-based intelligent new products by using car voice assistants as an example. Using the KANO model, select and evaluate functions that customers think are necessary for new products, and use the TOPSIS method to derives priorities by finding the importance of functions that customers need. For the analysis, major categories such as vehicle condition check and function control elements, driving-related elements, characteristics of voice assistant itself, infotainment elements, and daily life support elements were selected and customer demand attributes were subdivided. As a result of the analysis, high recognition accuracy should be considered as a top priority in the development of car voice assistants. Infotainment elements that provide customized content based on driver's biometric information and usage habits showed lower priorities than expected, while functions related to driver safety such as vehicle condition notification, driving assistance, and security, also showed as the functions that should be developed preferentially. This study is meaningful in that it presented a new product development methodology suitable for the characteristics of AI-based intelligent new products with innovative characteristics through an excellent model combining KANO and TOPSIS.

Study on the Fire Risk Prediction Assessment due to Deterioration contact of combustible cables in Underground Common Utility Tunnels (지하공동구내 가연성케이블의 열화접촉으로 인한 화재위험성 예측평가)

  • Ko, Jaesun
    • Journal of the Society of Disaster Information
    • /
    • v.11 no.1
    • /
    • pp.135-147
    • /
    • 2015
  • Recent underground common utility tunnels are underground facilities for jointly accommodating more than 2 kinds of air-conditioning and heating facilities, vacuum dust collector, information processing cables as well as electricity, telecommunications, waterworks, city gas, sewerage system required when citizens live their daily lives and facilities responsible for the central function of the country but it is difficult to cope with fire accidents quickly and hard to enter into common utility tunnels to extinguish a fire due to toxic gases and smoke generated when various cables are burnt. Thus, in the event of a fire, not only the nerve center of the country is paralyzed such as significant property damage and loss of communication etc. but citizen inconveniences are caused. Therefore, noticing that most fires break out by a short circuit due to electrical works and degradation contact due to combustible cables as the main causes of fires in domestic and foreign common utility tunnels fire cases that have occurred so far, the purpose of this paper is to scientifically analyze the behavior of a fire by producing the model of actual common utility tunnels and reproducing the fire. A fire experiment was conducted in a state that line type fixed temperature detector, fire door, connection deluge set and ventilation equipment are installed in underground common utility tunnels and transmission power distribution cables are coated with fire proof paints in a certain section and heating pipes are fire proof covered. As a result, in the case of Type II, the maximum temperature was measured as $932^{\circ}C$ and line type fixed temperature detector displayed the fire location exactly in the receiver at a constant temperature. And transmission power distribution cables painted with fire proof paints in a certain section, the case of Type III, were found not to be fire resistant and fire proof covered heating pipes to be fire resistant for about 30 minutes. Also, fire simulation was carried out by entering fire load during a real fire test and as a result, the maximum temperature is $943^{\circ}C$, almost identical with $932^{\circ}C$ during a real fire test. Therefore, it is considered that fire behaviour can be predicted by conducting fire simulation only with common utility tunnels fire load and result values of heat release rate, height of the smoke layer, concentration of O2, CO, CO2 etc. obtained by simulation are determined to be applied as the values during a real fire experiment. In the future, it is expected that more reliable information on domestic underground common utility tunnels fire accidents can be provided and it will contribute to construction and maintenance repair effectively and systematically by analyzing and accumulating experimental data on domestic underground common utility tunnels fire accidents built in this study and fire cases continuously every year and complementing laws and regulations and administration manuals etc.