• 한국화재소방학회논문지
• /
• 제33권6호
• /
• pp.20-27
• /
• 2019

본 연구는 화재 시 열출력 급상승 구간에 대한 정확한 열방출율을 예측하기 위한 새로운 함수를 개발하여 제안하는 것을 목적으로 하였다. 현재 화재공학에서 사용되고 있는 'αt²' 곡선은 화재시스템 공학 관점에서 비효율적이며 실효성 저하를 초래하므로 열방출율의 예측오차를 최소화시킬 필요가 있다. 'αt²'과 비교하여 보다 논리적인 배경과 형태적으로 유사성을 가진 로지스틱 함수 이론을 기반으로 화재 급성장 구간은 물론 화재 초기 단계까지 적용 가능한 새로운 예측 함수를 개발하였다. 개발된 함수는 더 넓은 화재성장 구간에서 정확도 높은 예측결과를 갖는 것으로 본 연구에서 증명되었다. 이 연구결과는 향후 화재성장패턴 연구의 개발과 함께 화재공학의 발전을 위해 적용될 것이다.

• 한국산학기술학회논문지
• /
• 제20권10호
• /
• pp.47-53
• /
• 2019

본 연구는 기존 연구에서 초점을 맞춘 1기간 모형과는 달리 2기간 모형에서 위험회피성향의 증가에 따라 노력의 투입에 따라 손실의 크기와 발생확률이 동시에 감소하는 손실통제 노력의 변화를 살펴보고 있다. 노력의 투입과 손실의 발생시점간의 시점 분리를 고려한 본 연구의 가정은 장기에서 위험회피성향의 영향을 관찰할 수 있게 해준다. 그 결과 첫째, 손실함수 및 비용함수에 추가적인 제약이 존재했던 단기 모형인 기존 연구와는 달리 장기에서는 위험회피성향의 증가가 손실통제 노력의 증가를 가져왔다. 둘째, 손실통제 노력을 자가보험 노력 및 자가보호 노력으로 세분화해 볼 때, 위험회피성향의 증가가 자가보험 노력은 증가시키나 자가보호에 미치는 영향이 불분명하던 기존 단기모형의 결과와는 달리, 장기에서는 위험회피성향의 증가로 인해 자가보험 노력 및 자가보호 노력이 모두 증가한다는 것을 알 수 있다. 셋째, 평균이 0인 배경위험이 존재하는 경우 2기간 모형에서 위험회피성향의 증가에 따라 손실통제 노력이 증가할 충분조건은 효용함수가 신중성 조건을 나타내는 것이다.

• 한국노년학
• /
• 제40권4호
• /
• pp.761-779
• /
• 2020

본 연구는 심층면접과 현상학적 분석을 적용한 질적연구로서 노인보호전문기관 종사자 경험으로부터 형성되는 의미를 해석하여 노인보호전문기관의 기능을 찾는데 목적을 두었다. 분석결과 본질적 주제는 '악전고투하며 일해 옴', '걷어내어지지 않는 장애물', '노인인권기구로 거듭나야 할 시기에 다다름'으로 나타났다. 이러한 주제들이 관통하고 있는 본질은 '인권지향으로 가는 길 : 쉽지 않아도 가야 할 목적지' 이다. 연구를 통해 찾아 낸 의미들이 지역사회에 연착륙하기 위해서는 노인보호전문기관에 대한 내·외적 지원 확대와 쇄신이 무엇보다 필요한 상황임을 제시하였다. 그 밖에 노인보호전문기관이 보다 전문성을 가지고 인권기구로 거듭날 수 있도록 법적·제도적 지원이 뒷받침되어야 할 필요 역시 함께 나타나는 만큼, 본 연구로부터 도출된 제도적 개선방안을 제언하였다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제25권3호
• /
• pp.393-400
• /
• 2012

The study was conducted to examine the effects of partially replacing soybean meal (SBM) by solid-state fermented cottonseed meal (FCSM) on growth performance, serum biochemical parameters and immune function of broilers. After inoculated with Bacillus subtilis BJ-1 for 48 h, the content of free gossypol in cottonseed meal was decreased from 0.82 to 0.21 g/kg. A total of 600, day-old male yellow-feathered broilers were randomly divided into four groups with three replicates of 50 chicks each. A corn-SBM based control diet was formulated and the experimental diets included 4, 8 or 12% FCSM, replacing SBM. Throughout the experiment, broilers fed 8% FCSM had higher (p<0.05) body weight gain than those fed 0, 4 and 12% FCSM. The feed intake in 8% FCSM group was superior (p<0.05) to other treatments from d 21 to 42. On d 21, the concentration of serum immunoglobin M in the 4% and 8% FCSM groups, as well as the content of complements (C3, C4) in 8% FCSM group were greater (p<0.05) than those in the SBM group. Besides, birds fed 8% FCSM had increased (p<0.05) serum immunoglobin M, immunoglobulin G and complement C4 levels on d 42 compared with bird fed control diet. No differences (p>0.05) were found between treatments regarding the serum biochemical parameters and the relative weights of immune organs. In conclusion, FCSM can be used in broiler diets at up to 12% of the total diet and an appropriate replacement of SBM with FCSM may improve growth performance and immunity in broilers.

• Corrosion Science and Technology
• /
• 제10권3호
• /
• pp.95-100
• /
• 2011

Protective coatings play an important role in the protection of metallic structures against corrosive environment. The main function of anticorrosive coating is to prevent the materials from corrosive agents, such as water, oxygen and ions. In the study, the corrosion protection properties of urethane and epoxy coating systems were evaluated using EIS methods exposed to the corrosion acceleration test such as Norsok M501, Prohesion and hygrothermal cyclic test. AFM analysis of the coating systems was carried out to monitor the change of roughness of coatings. Urethane coating system was more stable than the epoxy coating under given cyclic conditions. Water uptake into the urethane coatings was less than that into the epoxy coating. The urethane coating system showed better corrosion protection than epoxy coating system based on the changes of the impedance modulus at low frequency region with exposure time. Consequently, the corrosion protection properties of the epoxy and urethane coatings was well correspond with their surface roughness changes and water uptakes.

• 조명전기설비학회논문지
• /
• 제27권2호
• /
• pp.29-35
• /
• 2013

For the purpose of designing and applying optimum surge protection, one of the essential points is to take into account the energy coordination between cascaded surge protective devices(SPDs) and it is important to obtain an acceptable sharing of the energy stress between two cascaded SPDs. In this paper, in case of two voltage-limiting SPDs connected in parallel, the amount of splitting impulse current and energy that flow through each SPDs is investigated as a function of the protective distance. As a result, the energetic coordination between cascaded SPDs is strongly dependent on the voltage protection level of SPDs and the protective distance. It was confirmed that the sharing of the energy between two cascaded SPDs and the limited voltage levels are appropriate when the voltage protection levels of both upstream and downstream SPDs are the same.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2005년도 심포지엄 논문집 정보 및 제어부문
• /
• pp.90-92
• /
• 2005

In this paper, we design a digital protection IED(Intelligent Electric Device) for a distributed power system in connection with power grid. The device can measure various elements for protection and communicate with another devices through network. The protection IED is composed of specific function modules: signal process module which converts analog signal from PT and CT handle algorithm to digital one; communication module for connection with another IEDs; input/output module for user-interfaces; main control module for control the whole modules. A general purpose DSP board with TMS320C2812 is used in the IED. Experiments with the power system simulator DOBLE have been made to verily the proposed hardware system.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2005년도 심포지엄 논문집 정보 및 제어부문
• /
• pp.185-187
• /
• 2005

The reactor protection system is the most important function for the safe operation of nuclear powerplants (NPPs) in that such system protects a nuclear reactor tore whose damage can cause an enormous disaster to the nuclear facility and the public. A digital reactor protection system (DRPS) is being developed in KAERI for use in the newly-constructed NPPs and also for replacing the existing analog-type reactor Protection systems. In this paper, an software verification and validation (V&V) activities for DRPS, which are independent of the DRPS development processes, are described according to the software development life cycle. The main activities of DRPS V&V processes are the software planning documentations, the verification of software requirements specification (SRS) and software design specification (SDS), the verification of codes, the tests of the integrated software and system. Moreover, the software safety analysis and the software configuration management are involved in the DRPS V&V processes. All of the V&V activities are described, in detail, in this paper.

• 대한전기학회논문지:전력기술부문A
• /
• 제52권9호
• /
• pp.506-512
• /
• 2003

In this paper, a communication module between Relay agents in a multi-agent system based power distribution network protection system is realized using DNP3.0(Distributed Network Protocol), which is the standard communication protocol of distribution automation system in KEPCO. The key words for agent communication in the multi-agent based protection system are defined and represented by use of DNP application function code. The communication module developed based on the proposed communication scheme is tested by use of the Communication Test Harness, a test tool for DNP protocol, then used to the multi-agent system based power distribution net work protection system.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 하계학술대회 논문집 B
• /
• pp.1373-1375
• /
• 2004

This paper presents the design of DC protection Relay for Light Rail Transit system, which is very beginning product in domestic. Protection Function characteristic, principle and I/O interface including interlock signal has been introduced. The protection algorithm and EMC characteristics have been certified by official organization and Type test report has been introduced. Up to date in domestic, the test procedure for DC Protection relay hasn't been established so the new method and test equipment based on IEC regulations are proposed. Finally the product will be proved based on field test.