• Title/Summary/Keyword: Protective Effectiveness

Search Result 158, Processing Time 0.026 seconds

Analysis of the Protective Distance of Low-Voltage Surge Protective Device(SPD) to Equipment (저압용 서지 보호 장치(SPD)의 보호 거리 해석)

  • Lee, Jung-Woo;Oh, Yong-Taek
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.26 no.4
    • /
    • pp.28-34
    • /
    • 2012
  • Installing surge protection devices for a low-voltage system is important to ensure the survival of electric or electronic devices and systems. If surge protection devices (SPD) are installed without consideration of the concept of lightning protection zones, the equipment to be protected might be damaged despite the correct energy coordination of SPDs. This damage is induced by the reflection phenomena on the cable connecting an external SPD and the load protected. These reflection phenomena depend on the characteristics of the output of the external SPD, the input of the loads, and the cables between the load and the external SPD. Therefore, the SPD has an effective protection distance under the condition of the specific load and the specific voltage protection level of SPD. In this paper, PSCAD/EMTDC software is used to simulate the residual voltage characteristics of SPD Entering the low-voltage device. And by applying a certain voltage level, the effective protection distances of SPD were analyzed according to the each load and length of connecting cable, and the effectiveness of SPD were verified.

Effects of a Finger Guard while Opening the Glass Ampoule by Nursing Students (손가락보호대의 적용이 간호대학생의 유리앰플 개봉 시 찔림사고, 불안 및 사용자만족도에 미치는 효과)

  • Lee, Jung-Ok
    • Journal of Korean Biological Nursing Science
    • /
    • v.21 no.4
    • /
    • pp.318-325
    • /
    • 2019
  • Purpose: The purpose of this study was to identify the effects of a finger guard developed to prevent sharp injuries in nursing students. Methods: This study was an equivalent control group posttest design. Seventy nursing students were randomly allocated to either the experimental group (n= 35) or the control group (n= 35). The finger guard was used whileopening the glass ampoule in the experimental group. The outcome variables such as sharp injuries, anxiety and user satisfaction were measured. Results: Sharp injuries were 0 in the experimental group and 2 in the control group (p= .160). Anxiety in the experimental group was significantly lower than the control group (p< .001). User satisfaction was 4.33 score in the range from 1 to 5, the highest item was the weight (4.63), followed by effectiveness (4.51). Conclusion: Using a protective device while opening the glass ampoule was observed to be effective in reducing anxiety among the nursing students, and exhibited protection of skin.

The Emulsification of Silane as Water REpellent for Concrete (콘크리트 발수제용 Silane의 유화)

  • 황인동;염희남;정윤중
    • Journal of the Korean Ceramic Society
    • /
    • v.37 no.8
    • /
    • pp.760-767
    • /
    • 2000
  • Recently, the protection of construction is demanded with environmental pollution. These protect modes are use of concrete admixture, coat of protective polymer and impregnate of surface with chemicals etc. The most widely used impregnation is economical and effective. The define of Impregnation for construction protect is reacted in and consolidated substrate after absorbed. The impregnation agents are Polyesters, Acrylic monomers, Epoxy and Silicone derivatives. Commonly, because the Silane has good water repellency and environmental advantages that it widely used to water proofing agents, dampproofing agents and absorption reducer for concrete of bridges. When application of Silane, it occurs pollution and harmfulness as included organic solvent. The manufactures have tired to emulsification of Silane for the reducing of the defects. The Silane emulsion is vary unstable and does not stored long periods, and it is diminished in good properties with internal reaction. In this study we tried to emulsification of Silane for effectiveness improvement and reduce pollution and hazard and discussed properties variation of emulsion. The Silane emulsions are achieved emulsifying with W/O and O/W type surfactants. It used 0.24% PVA as protective colloid and stable phase is creamy. The creamy Silane emulsion performance as the penetration depth and water absorption rate are above 4 mm and below 0.1. It stable about 6 month at room temperature.

  • PDF

Photo oxidation of Rice Bran Oil and Protective Action of Antioxidants (미강유의 광산화와 항산화제의 방어작용)

  • Paik, Tai-Hong;Lee, Young-Kuk
    • Journal of the Korean Applied Science and Technology
    • /
    • v.4 no.1
    • /
    • pp.19-22
    • /
    • 1987
  • To investigate the protective action of various antioxidants on the photooxidation of rice bran oil, it was irradiated with red and visible light in presence and absence antioxidants with or without sensitizer (methylene blue). 1. Rice bran oil with and without sensitizer in chloroform-ethanol (4:1, v/v) media was largely oxidized under visible light irradiation. on the other hand, rice bran oil without sensitizer was hardly oxidized under red light irradiation. 2. Rice bran oil with sensitizer was oxidized much faster than that without. And the absorbance of it irradiated with visible was increased more than that with red light. 3. The effectiveness of antioxidants on the rice bran oil photooxidation was same order as follows: Irradiation with visible light, no addition of sensitizer ${\beta}$-carotene > dl-{$\alpha}$-tocopherol > BHT > BHA Irradiation with visible light, addition of sensitizer ${\beta}$-carotene > BHT > dl-${\alpha}$tocopherol > BHA Irradiation with red light, addition of sensitizer ${\beta}$-carotene > BHA > BHT > dl-${\alpha}$-tocopherol From these results, we concluded that rice bran oil was largely oxidized under visible light irradiation, therefore it must be protected from photooxidative deterioration by the addition of antioxidants.

Using Design to Make Doffing of Personal Protective Equipment Safer for Healthcare Workers (의료종사자의 안전한 개인보호장비 탈의를 위한 공간 설계에 관한 연구)

  • Matic, Zorana;Oh, Yeinn;Lim, Lisa
    • Journal of The Korea Institute of Healthcare Architecture
    • /
    • v.26 no.3
    • /
    • pp.17-26
    • /
    • 2020
  • Purpose: This paper presents research evidence that the environmental design of the doffing area in a biocontainment unit (BCU) can have a measurable impact on increasing the safety of frontline healthcare workers (HCW) during doffing of high-level personal protective equipment (PPE), and proposes optimized biocontainment unit design. Methods: From 2016 to 2019, The SimTigrate Design Lab conducted 3 consecutive studies, focusing on ways in which the built environment may support or hinder safe doffing. In the first study, to identify the risky behaviors, we observed 56 simulation exercises with HCWs in 4 BCUs and 1 high-fidelity BCU mockup. In the second study, we tested the effectiveness of a redesigned doffing area on improving the HCWs performance and used simulation, observation, and rapid prototyping in 1 high-fidelity mockup of a doffing area. In a follow-up study, we used simulation and co-design with HCWs to optimize the design of a safer doffing area in a full-size pediatric BCU mock-up. Results: We identified 11 specific risky behaviors potentially leading to occupational injury, or contamination of the PPE, or of the environment. We developed design strategies to create a space for safer doffing. In the second study, in a redesigned doffing area, the overall performance of HCW improved, and we observed a significant decrease in the number of risky behaviors; some risky behaviors were eliminated. There was a significant decrease in physical and cognitive load for the HCWs. Finally, we propose an optimized layout of a BCU for a safer process of PPE doffing. Implications: The proposed BCU design supports better staff communication, efficiency, and automates safer behaviors. Our findings can be used to develop design guidelines for spaces where patients with other highly infectious diseases are treated when the safety of the patient-facing HCWs is of critical importance.

Pure inorganic protective silica coating on stainless steel prepared at low heat treatment temperature

  • Hwang, Tae-Jin
    • Proceedings of the Materials Research Society of Korea Conference
    • /
    • 2010.05a
    • /
    • pp.6.2-6.2
    • /
    • 2010
  • Stainless steel is widely known to have superior corrosion properties. However, in some harsh conditions it still suffers various kinds of corrosions such as galvanic corrosion, pitting corrosion, intergranular corrosion, chloride stress corrosion cracking, and etc. For the corrosion protection of stainless steel, the ceramic coatings such as protective silica film can be used. The sol-gel coating technique for the silica film has been extensively studied especially because of the cost effectiveness. It has been proved that silica can improve the oxidation and the acidic corrosion resistance of metal surface in a wide range of temperatures due to its high heat and chemical resistance. However, in the sol-gel coating process there used to engage a heat treatment at an elevated temperature like $500^{\circ}C{\sim}600^{\circ}C$ where cracks in the silica film would be formed because of the thermal expansion mismatch with the metal. The cracks and pores of the film would deteriorate the corrosion resistance. When the heat treatment temperature is reduced while keeping the adhesion and the density of the film, it could possibly give the enhanced corrosion resistance. In this respect, inorganic protective silica film was tried on the surface of stainless steel using a sol-gel chemical route where silica nanoparticles, tetraethoxysilane (TEOS) and methyltriethoxysilane (MTES) were used. Silica nanoparticles with different sizes were mixed and then the film was deposited on the stainless steel substrate. It was intended by mixing the small and the large particles at the same time a sufficient consolidation of the film is possible because of the high surface activity of the small nanoparticles and a modest silica film is obtained with a low temperature heat treatment at as low as $200^{\circ}C$. The prepared film showed enhanced adhesion when compared with a silica film without nanoparticle addition. The films also showed improved protect ability against corrosion.

  • PDF

A Study on the Development and Application of Digital Protective Relay for DC Feeding System of Light Rail Transit System (경전철 직류급전계통을 위한 디지털 보호제어장치의 개발 및 적용에 관한 연구)

  • Baek, Byung-San;Kim, Jae-Chul
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.19 no.2
    • /
    • pp.77-86
    • /
    • 2005
  • The DC protection and control device for the feeding system of a Light Rail Transit(LRT) system is developed. For the development, the short circuit characteristics in the system are analyzed. As a result a protection algorithm for the DC fault selective relay (50F) is newly proposed, and principles of the DC fault selective relay, Line Test Device (LTD), DC Over Current Relay (DC OCR) are introduced From the development, the specifications and codes used to be unclear have become clarified and summarized. Moreover, the methods to examine the protective characteristics and Electromagnetic Compatibility (EMC) are established Finally, the performance and the effectiveness of the developed protective relay have been verified with the test based on IEC. For the reliability of the system, the relay has been installed and is being operated at the test track of the LRT system at Gyeong-San.

User Acceptance of a Light-Emitting Diode Vest for Police Officer

  • Han, Hyunjeong;Park, Huiju;Jeon, Eunkyung
    • Fashion & Textile Research Journal
    • /
    • v.15 no.5
    • /
    • pp.834-840
    • /
    • 2013
  • This study aims to suggest practical considerations for designing protective clothing with increased visibility that will have higher user acceptance by law enforcement officers. Light-emitting diode(LED) patrol vests were visually and structurally assessed, and 125 police officers' responses from surveys about user acceptance of the vest were analyzed. The current LED patrol vest was designed for enhanced safety of police officers by increasing visibility in the dark. However, the user acceptance rate of the LED patrol vest indicates low use of and low satisfaction with the vest despite its enhanced safety features. In particular, differences in materials, design, functionality of the pockets and size of the vest depending on the hours worked, were statistically significant. The police officers' responses suggest areas of improvement in design, materials, ease of movement, size and functionality. Key issues include 'tactile discomfort'; 'impeded vision from the glare of the LED'; 'frequent malfunctions of the LED'; 'impossible repair of the broken LED units'; 'no user feedback'; 'inconvenient to replace batteries'; 'brittle materials' and 'unpleasing look'. To increase user acceptance, designer should incorporate context-awareness, a convenient user interface, a modular design approach, first responders' self-image as public servants in relation to their aesthetic perspectives of their uniforms, and scientific evaluation of the effectiveness of the intended functions of the clothing. Suggested implications for designing the LED patrol vest can be applied to designing other functional/protective clothing for intended end users with special needs.

A Study on the Operational Problems and Improvement Plan of the Domestic Violence Punishment Act through Domestic Violence Crime Information Analysis

  • Yoon, Hyun-Seok
    • Journal of the Korea Society of Computer and Information
    • /
    • v.26 no.11
    • /
    • pp.227-232
    • /
    • 2021
  • The 「Act on Special Cases concerning the Punishment of Crimes of Domestic Violence」 still has various problems in the legal system and enforcement process. Contrary to the original intention of the legislation, it is operated very passively in terms of state intervention and punishment of domestic violence actors in actual operation. Even if it is treated as a home protection case, if you look at the details of the protection disposition, there is a problem that the decision on the protection disposition is biased towards a specific type of protection disposition. In order to improve this, the need for cooperation and active intervention between state agencies is required. In addition, it is necessary to establish a legal basis for a request for personal protection by recognizing the status of a victim who reported domestic violence as a crime reporter. In addition, in order to secure the effectiveness of the protective disposition, it is necessary to strengthen sanctions for non-compliance or violations of the protective disposition.

Analysis of the Effectiveness of Emergency Response Measures during the Design Basis Accident of the Research Reactor 'HANARO' using MACCS2 Code (MACCS2 코드를 이용한 연구용원자로 '하나로' 설계기준사고시 비상대응조치 효과분석)

  • Lee, Goan-Yup;Kim, Jong-Su;Lee, Hae-Cho;Kim, Bong-Suk
    • Journal of Radiation Protection and Research
    • /
    • v.39 no.2
    • /
    • pp.109-117
    • /
    • 2014
  • Nuclear emergency planning is to plan sheltering, evacuation and iodine prophylaxis for the residents living in the area where the emergency plan is needed, the area is confirmed based on the dose assessment using the source-term through an accident analysis and the data measured from meteorological tower. In this study, the does change before and after protective measures was assessed stochastically based on the one year meteorological data in the condition of the maximum hypothetical accident which can be considered at the research reactor 'HANARO', and the optimized protective measures were derived based on the reference levels defined as a residual dose by ICRP 2007 recommendation which can be applied in a emergency exposure situation. The optimized protective measures for the HANARO in the maximum hypothetical accident were the evacuation to radius 300 m, the sheltering from 300 m to 800 m, the iodine prophylaxis only for the emergency workers under the protective measures for non emergency workers.