• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.63-64
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• 2011

• 대한수학회보
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• 제35권1호
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• pp.63-74
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• 1998

Our study is dedicated to the the proof of uniqueness of solution of initially boundary value problem in Elastodynamics of initially stressed bodies with voids. This proof is obtained without recourse either to an energy conservation law or to any boundedness assumptions on the elastic coefficients.

• 플랜트 저널
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• 제14권1호
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• pp.34-41
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• 2018

과거의 학문은 기초의 시대이며, 현재의 학문은 융합의 시대이며, 미래의 학문은 통합의 시대이다. 학문 통합의 필수 조건은 모든 학문이 서로 동등해야 한다는 것이며, 오직 자연법칙으로부터 파생된 법칙만이 통합의 동등성을 구현할 수 있을 것이다. 변화를 일으킬 수 있는 능력을 에너지로 정의할 것을 제안한다. 만물은 변화하며 그 변화에는 방향성이 필히 존재하므로, 변화와 방향성은 모든 학문에 동등하게 적용된다. 통합학문의 제 0 법칙은 존재의 법칙, 제 1 법칙은 변화 보존의 법칙, 제 2 법칙은 무효변화 증가의 법칙, 제 3 법칙은 지침의 법칙, 그리고 제 4 법칙은 융합의 법칙이다. 위 법칙들은 열역학의 자연법칙과 매우 유사함을 볼 수 있다. 통합학문 5 대 법칙의 최종 목표는 지구상에서 자연, 인간, 인공지능 개체들이 서로 협력하여 발전하는 공동체의 구현이다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2015년도 전력전자학술대회 논문집
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• pp.179-180
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• 2015

The task of measuring losses becomes more challenging with ever increasing efficiencies and operating frequencies in power electronics applications. Generally, the process of traditional switching loss calculation in flyback converter is very complicated. MOSFET drain-source voltage and current waveforms are needed to calculate switching loss. However, as we know in switched capacitor converter, switching loss can be easily calculated by charge and energy conservation law with known initial and final capacitor voltages. In this paper, the same method is applied to fly-back converter switching loss analysis to simplify calculation procedure.

• 한국철도학회논문집
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• 제3권4호
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• pp.177-184
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• 2000

In this paper, a HVAC controller which has a bilinear system is designed to control the air temperature in building room and a saving of energy on the HVAC system. For modeling of the HVAC bilinear system, AHU(Air Handling Unit) is modeled on the control of inside-outside air flow using three dampers in a duct. A heat exchanger and the single room are also modeled by the energy conservation law. Under the modeling of the HVAC bilinear system, the control's law of the bilinear HVAC system is derived by Lyapunov's non-linear theory and Deress's the linear feedback laws for bilinear system. In this paper it was proved that the controller of the HVAC bilinear system is able to control the air temperature with a disturbance in order to get a target of temperature in the building room by the computer simulation when the control inputs regulate the air flow rate and a capacity of the heat exchanger.

• Earthquakes and Structures
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• 제18권6호
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• pp.743-752
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• 2020

The phenomenon of reflection and transmission of plane waves at an interface between fluid half space and orthotropic piezothermoelastic solid half-space with two-temperature has been investigated. Energy ratios of various reflected and transmitted waves are computed with the use of amplitude ratios. The law of conservation of energy across the interface has been justified. It is found that the energy ratios are the functions of angle of incidence, frequency of independent wave and depend on the different piezothermoelastic material. A piezothermoelastic material has been considered which is in welded contact with water. Variations of energy ratios corresponding to the reflected waves and transmitted waves are computed and shown graphically for the two different models. A particular reduced case of interest is also discussed.

• 한국화재소방학회논문지
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• 제13권4호
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• pp.30-37
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• 1999

본 연구에서는 아트리움 공간에서의 화재성상을 파악하기 위해 실물 실현의 대안으로서 축소 모형 실험을 수행하였다. 연속방정식, 운동량 보존 방정식, 에너지 보존 방정식과 같은 지배 방정식의 차원해석으로부터 추론된 $\pi$변수로부터 축소법칙을 얻었다. 이 축소법칙에 따라 일본의 시반스 아트리움을 1/50로 축소한 모형에서 실험을 수행하였다. 여기서 얻어진결과를 실물 실험 결과와 비교하였다. 더 나아가 이러한 결과들은 레이저 관광을 이용한 가시화 시스템에 의해 가시화 되어졌다.

• 한국재난정보학회 논문집
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• 제19권4호
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• pp.844-850
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• 2023

연구목적: 본 논문은 백열전구를 이용하여 단락보호 전원공급 장치를 개발하고, 이를 학습 교구로 활용하는 연구에 관한 것이다. 전기 안전과 에너지 절약을 동시에 고려한 이 연구는 교육과 산업 분야에서 중요한 응용 가능성을 가지고 있다. 백열전구를 활용한 단락보호 전원공급 장치는 기존의 전원공급 장치와 비교하여 안전성과 효율성을 향상시키는데 도움이 되며, 학습 교구로 학습자들에게 전기 안전 교육을 제공함으로써 실생활에서의 전기 안전 지식을 습득하는데 기여한다. 연구방법: 백열전구를 사용하여 단락보호 전원공급 장치를 개발하고 개발된 장치의 성능 평가 및 안전성 확인을 통해 학습 교구로 활용할 수 있는 새로운 전원공급장치를 제작 한다. 결론:백열전구를 활용한 단락보호 전원공급 장치의 개발과 학습 교구로의 응용 가능성을 탐구한 연구이다. 이를 통해 전기 안전과 에너지 절약에 기여할 수 있는 혁신적인 솔루션을 제시하였으며, 교육 분야와 산업 분야에서의 응용 가능성을 열어놓았다. 이러한 연구는 전기 안전 및 에너지 관리 분야에서의 연구와 교육에 기여할 것으로 기대된다.

• Nuclear Engineering and Technology
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• 제35권5호
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• pp.482-496
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• 2003

effectiveness of the PAM graphite-electrode technology for the treatment of many types of low-level radioactive waste including : combustible material, solidified resins in cement, inorganic materials, steel, glass, and solidified boric acid cement. The objectives of PAM-200 evaluation were to verify that 1) the facility meets air emission regulations, 2) the facility can be safely operated when processing hazardous and radioactive materials and 3) satisfactory final waste forms can be produced. Results, derived from KAERI's(Korea Atomic Energy Research Institute) analyses for samples of vitrified product, scrubbing solution and offgas collected during test period, show that PAM-200 can treat radioactive wastes as well as hazardous wastes with toxic constituents and radionuclides contained in the offgas exiting from the stack to the environment controlled to be far lower than the limit regulated by air conservation law and atomic law.

• Geomechanics and Engineering
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• 제28권6호
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• pp.613-624
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• 2022

A study of the evolution of overburden fractures under the solid-fluid coupling state was conducted based on the geological and mining characteristics of the coal seam depth, weak strata cementation, and high-intensity mining in the mining areas of West China. These mining characteristics are key to achieving water conservation during mining or establishing groundwater reservoirs in coal mines. Based on the engineering background of the Daliuta Coal Mine, a non-hydrophilic simulation material suitable for simulating the weakly cemented rock masses in this area was developed, and a physical simulation test was carried out using a water-sand gushing test system. The study explored the spatial distribution and dynamic evolution of the fractured zone in the mining overburden under the coupling of stress and seepage. The experimental results show that the mining overburden can be vertically divided into the overall migration zone, the fracture extension zone and the collapse zone; additionally, in the horizontal direction, the mining overburden can be divided into the primary fracture zone, periodic fracture zone, and stop-fracture zone. The scope of groundwater flow in the overburden gradually expands with the mining of coal seams. When a stable water inrush channel is formed, other areas no longer generate new channels, and the unstable water inrush channels gradually close. Finally, the primary fracture area becomes the main water inrush channel for coal mines. The numerical simulation results indicate that the overlying rock breaking above the middle of the mined-out area allows the formation of the water-conducting channel. The water body will flow into the fracture extension zone with the shortest path, resulting in the occurrence of water bursting accidents in the mining face. The experimental research results provide a theoretical basis for the implementation of water conservation mining or the establishment of groundwater reservoirs in western mining areas, and this theoretical basis has considerable application and promotion value.