• Geomechanics and Engineering
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• 제14권6호
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• pp.581-588
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• 2018

In order to explore the comprehensive evaluation means of the extent of hydraulic fracturing region in coal seams, we analyzed the feasibility of detecting the response of coal rock direct current (DC) apparent resistivity to hydraulic-fracturing using Archie's theory, and conducted experimental researches on the response of DC resistivity in the hydraulic fracturing process using small-scale coal rock samples. The results show that porosity and water saturation are the two factors affecting the apparent resistivity of coal rock while hydraulic fracturing. Water has a dominant effect on the apparent resistivity of coal rock samples. The apparent resistivity in the area where water flows through is reduced more than 50%, which can be considered as a core affect region of hydraulic fracturing. Stress indirectly impacts the apparent resistivity by changing porosity. Before hydraulic fracturing, the greater axial load applied, the more serious the rupture in the samples, resulting in the greater apparent resistivity. Apparent resistivity testing is a potential regional method to evaluate the influence range of hydraulic fracturing in coal seams.

• 대한지리학회지
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• 제50권3호
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• pp.355-373
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• 2015

본 연구에서는 화재로 인한 피해에 영향을 주는 여러 요인들에 대한 사전 연구를 살펴보고, 주요 화재피해 결정요인에 대한 모델을 만들고 지역환경 요소와 화재피해요소의 변수를 선정하여 상호인과관계 모형을 정립하였다. 모델의 유효성을 검증하기 위하여 228개의 시군구 자치단체별로 공표된 통계를 선정하여, 화재피해에 대한 4개의 종속변수와 22개의 독립변수를 선정하여 검증을 하였다. 독립변수는 인적 취약성, 물리적 취약성, 경제적 취약성 및 경감요소와 지역의 특성으로 구분하여 구성하였다. 선택된 변수의 상관관계를 분석하기 위하여 준로그 모형을 적용하여 회귀분석을 수행하였다. 22개의 독립변수 중에서 만명당 재난약자수, 만명당 제조업 종사주수, 만명당 연료소매업 종사자수, 만명당 음식 요식업 종사자수는 화재의 발생건수와 유의미한 상관관계를 보여주었으며, 이와는 달리 화재로 인한 사망자수는 만명당 사회복지사수와 상업지구비율과 유의미한 상관관계를 보였다. 이외에 화재로 인한 경제적 손실값을 설명하는 변수로는 만명당 부과된 재산세가 유의미한 변수로 도출되었다. 단순히 인구와 면적으로 소방에 필요한 자원을 배분하지 않고 피해에 영향을 주는 변수를 고려해야 할 것으로 사료되며 이 결과물은 화재예방정책과 화재안전을 제고하는 데 기여할 것으로 기대된다.

• 응용통계연구
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• 제22권1호
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• pp.221-235
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• 2009

This manuscript illustrates the comparative study between ARIMA and Exponential Smoothing modeling to develop forest fire forecasting system using different weather parameters. In this paper, authors have developed the most suitable and closest forecasting models like ARIMA and Exponential Smoothing techniques using different weather parameters. Authors have considered the extremes of the Wind speed, Radiation, Maximum Temperature and Deviation Temperature of the Summer Season form March to June month for the Ranchi Region in Jharkhand. The data is taken by own resource with the help of Automatic Weather Station. This paper consists a deep study of the effect of extreme values of the different parameters on the weather fluctuations which creates forest fires in the region. In this paper, the numerical illustration has been incorporated to support the present study. Comparative study of different suitable models also incorporated and best fitted model has been tested for these parameters.

• International Journal of Internet, Broadcasting and Communication
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• 제8권2호
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• pp.55-65
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• 2016

Distributed Denial of service attack is one of the major threats nowadays especially to the government infrastructure that give huge impact to the reputation and interrupt the services and resource. Our survey start with brief introduction about DDoS attacks, we illustrate the trends and incident happened at government from various countries. We then provide an extensive literature review on the existing research about implication, types of attacks and initiative to defence against the DDoS attacks. Our discussion aims to identify the trends in DDoS attacks, in depth impact of DDoS attacks to government infrastructure, classification of attacks and techniques against the attacks. And we will use for a fire fight safety and management.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.149-150
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• 2016

The membrane structure is being applied in structures for various uses for its many advantages as permeableness, lightweightness, constructability, resource saving, and management cost reduction, and the usage is being expanded. However, despite the development of membrane structure, the standard for architectural membrane performance that considered fire safety is still inadequate. Therefore, this study applied basalt fiber with flame resistance on architectural membrane. Also, this study confirmed the membrane applicability of basalt fiber through comparison with existing architectural membrane.

• 한국군사과학기술학회지
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• 제14권3호
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• pp.380-387
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• 2011

In this paper, we considered the authoritative representation of Command and Fire Control System(CFCS) for the surface ship that was the engineering level model to develop system specifications and to analyze operational concepts on the concept design phase and to analyze military requirements, effectiveness and performance for the system. The engineering level model of CFCS can be used in simulation independently of the surface ship's type, and also it takes reuse, interoperability, and extension into consideration. The detailed sub-models, internal and external data interface, data flow among each sub-model, sensor and weapon models about the engineering level model of CFCS was defined. It was verified via engineering level simulations according to the V&V process.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.149-154
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• 2007

Now, in Korea, the performances of the building service equipment relay on the individual superintendent's share for the assessment of performance, fault detection, deterioration diagnosis of the building service equipment. As the result, very different quality of the performance or the durability of equipment is being obtained with his skill and effort and it is also not easy to assess that quality. This finally lead to the waste of labor force and the operating cost due to the high-cost, low-efficiency system. How to construct the N-BMS was considered to save energy, resource and to conserve performance of building service equipment. The FEMIS, facility, energy/environmental management & information system, for building service offer management process integrated with BAS, FMS and EMS and so on.

• 한국광물학회지
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• 제32권3호
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• pp.185-200
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• 2019

본 연구목적은 비-가시성 금 정광(Au = 1,840.00 g/t)으로부터 금을 단체분리 시키기 위하여 마이크로웨이브-질산침출 실험을 수행하였다. 이를 위해 질산농도 효과, 마이크로웨이브 침출시간 효과 그리고 시료 첨가량 효과에 대하여 마이크로웨이브-질산침출 실험을 수행하였다. 본 연구의 실험조건에서는 금이 전혀 침출되지 않은 것으로 조사되었다. 불용성-잔류물의 무게는 질산 농도, 마이크로웨이브 침출시간 그리고 시료 첨가량이 증가할수록 감소하는 경향으로 나타났다. 불용성-잔류물에 대하여 XRD 분석한 결과 석고와 anglesite가 나타나는데 이는 정광에 포함된 방해석과 방연석이 질산용액과 반응하여 생성된 것으로 사료된다. 불용성-잔류물에 대하여 납-시금법을 수행한 결과 정광보다 금함량이 최소 1.3배(Au = 2,464.70 g/t)에서 최대 28.8배(52,952.80 g/t)로 높게 나타났다. 그러나 납-시금법에서 회수된 금 함량은 gold nugget effect가 매우 심하게 나타났다. 향후, 마이크로웨이브-질산침출 실험에서 정광의 시료채취 방법을 개선하고, 더 작은 기공 크기의 여과지를 사용하여 침출용액을 여과하고 납-시금법에서 여과지를 태워서 시료로 투입하는 방법을 수행한다면 gold nugget effect를 감소시킬 수 있을 것으로 기대된다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.110-115
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• 2010

최근 도심지의 지하철 노선들은 과거에 지어진 지하철 노선들에 비하여 대심도 터널이 증대하고 있다. 신금호 역사(5호선, 깊이 : 46m)는 수도권에 있는 지하철 역사 중에서 3번째로 깊은 역사로서 대심도 역사의 모델로 선정되었으며, 신금호 전체 역사에 대한 화재시뮬레이션을 시도하였다. 신금호 역사는 3개의 출입구, 지하 1층 대합실, 지하 2층 대합실, 지하 2층에서 8층으로의 연결통로, 지하 8층 승강장으로 구성되어 있다. 본 연구에서는 지하 8층 승강장에서 지상 출입구 까지 전체 역사를 대상으로 연기거동을 해석하기 위하여 9,000,000개의 격자를 생성하였으며, 계산 효율을 증대시키기 위하여 19개의 블록으로 나누어서 처리하였다. 화재해석은 화재에 특화된 CFD 코드인 FDS를 사용하였으며 난류해석 기법은 LES가 사용되었다. MPI의 병렬처리기법을 이용하여 19개의 블록을 각각의 CPU에서 분산처리 하였다. 본 전산수치해석에 사용된 CPU 자원은 Intel 3.0 GHz Dual CPU 10개 (Core 20개)이다.

• 대한안전경영과학회지
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• 제17권3호
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• pp.195-204
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• 2015

The live fire test has been playing a critical role in evaluating the goals-to-meet of the weapon systems which utilize the power of explosives. As such, the successful development of the test systems therein is quite important. The test systems development covers that of ranges and facilities including system-level key components such as mission control, instrumentation or observation, safety control, electric power, launch pad, and so on. In addition, proper operational guidelines are needed with well-trained test and operation personnel. The emerging weapon systems to be deployed in future battle field would thus have to be more precise and dynamic, smarter, thereby requiring more elaboration. Furthermore, the safety consideration is becoming more serious due to the ever-increasing power of explosives. In such a situation, development of live fire test systems seems to be challenging. The objective of the paper is on how to incorporate the safety and other requirements in the development. To achieve the goal, an architectural approach is adopted by utilizing both the system components relationship and safety requirement when advanced instrumentation technology needs to be developed and deteriorated components of the range are replaced. As an evaluation method, it is studied how the level of maturity of the test systems development can be assessed particularly with the safety requirement considered. Based on the concepts of both systems engineering and SoS (System-of-Systems) engineering process, an enhanced model for the system readiness level is proposed by incorporating safety. The maturity model proposed would be helpful in assessing the maturity of safety-critical systems development whereas the costing model would provide a guide on how the reasonable test resource allocation plan can be made, which is based on the live fire test scenario of future complex weapon systems such as SoS.