• 대한환경공학회지
• /
• 제22권11호
• /
• pp.2017-2023
• /
• 2000

정유폐수의 성상에 적합한 동역학적 모델을 적용하여 활성슬러지법으로 처리할 때 모델의 적합성을 검토하기 위하여 실제 정유폐수 처리장 포기조내의 환경인자의 변화와 유출수 특성을 비교하였다 활성슬러지 포기조내 DO, pH, MLSS, COD의 실제 측정값과 비교하였다. Simulation한 결과, 유출수 평균 COD가 19.0~19.4mg/L로 측정 COD 23.1mg/L와 잘 일치하였고, 포기조내 평균 DO는 1.9~2.4mg/L로 예측되었는데 측정된 평균 DO가 2.2mg/L로 잘 일치하여 모델의 정유폐수 처리장의 적용 가능성이 검토되었다.

• 환경영향평가
• /
• 제8권1호
• /
• pp.29-40
• /
• 1999

This study focuses on one of typical energy-intensive industries, the cement industry. The purpose of the study is to propose $SO_2$ emission reduction measures in the cement industry. This study partially employed and modified AIM(Asia-Pacific Integrated Model) developed by Japan National Environmental Research Institute to develop AIM/KOREA SULFUR model for simulation. In the study, a base scenario, and mitigation scenarios(a use of low-sulfur contain fuel, fuel conversion to cleaner energy, an induction of desulfurization systems, and energy saving) were employed. The results of the simulation are summarized below: The sulphur dioxide emission from the cement industry in 1992 was estimated to be 106,000 metric tons; however, according to base scenario, sulphur dioxide emission is expected to be increased to 219,000 metric tons, which is 2.1 times greater than that in 1992 by year 2020. To alleviate such increasement, simulation results under various scenarios proved that some degrees of reduction may be possible by an induction of desulfulization systems although there may be numerous ways to interpretate the simulation results.

• 한국시뮬레이션학회논문지
• /
• 제14권2호
• /
• pp.15-24
• /
• 2005

The goal of a distributed simulation such as battle field simulation is to combine all kinds of simulations in the same synthetic environment and to make people interact at the same time. It is a key issue to share the same synthetic environment among simulations. To support reusability and affordability in the modeling and simulation area, DMSO(Defense Modeling and Simulation Office) of USA developed concepts such as HLA(High Level Architecture) and SEDRIS (Synthetic Environmental Data Representation and Interchange Specification). In the industrial simulation area, the digital manufacturing is the main stream. To reduce cost and to reuse simulation environment, the standardization becomes the focus of digital manufacturing. This study proposes to use SEDRIS to improve interoperability of manufacturing data. The simulation data of DELMIA, which is a leading commercial digital manufacturing solution, is mapped and translated into the SEDRIS transmittal format. Mapping of the manufacturing simulation data and the synthetic environment are implemented and verified through experiments.

• 한국해양공학회지
• /
• 제17권4호
• /
• pp.1-7
• /
• 2003

A virtual reality technology for multipurpose numerical simulation is developed to reproduce and investigate a variety of ocean environmental problems in a 3D Numerical Wave Tank(NWT). The governing equations for solving incompressible fluid motion are Navier-Stokes equation and continuity equation. The Marker-Density function technique is adopted to implement the fully nonlinear freesurface kinematic condition. The marine environmental situations, i.e., waves, currents, etc., are reproduced by use of multi-segmented wavemakers on the basis of the so-called ″snake-principle″. In this paper, some numerical reproduction techniques for regular, and irregular waves, multi-directional waves, Bull's-eye wave. wave-current, and solitary wave are presented, and a model test in motion with large amplitude of roll angle is conducted in the developed 3D-NWT, using a overlaid grid system.

• 한국시뮬레이션학회논문지
• /
• 제13권2호
• /
• pp.35-43
• /
• 2004

The purpose of this study is an economic analysis of power plant utilities by comparing electricity generating cost including environmental costs. Considering the enormous role of electricity in the national economy, it is very important to study the effect of environmental regulation on the electricity sector. Because power utilities need for large investment during construction, operation and maintenance, and also require much construction lead time. Economic analysis is the important process in the electric system expansion planning. This paper compares the costs of electricity generation including environmental costs between a coal-fired power plant and an LNG combined cycle power plants. With the simulation, this study surveys the sensitivity of fuel prices, interest rate and carbon tax. In each case, this sensitivity can help to decide which utility is economically better in environmental regulation circumstance.

• 설비공학논문집
• /
• 제10권3호
• /
• pp.251-259
• /
• 1998

Environmental control facilities are used to simulate an environment or combination of environments under which many kinds of research and tests can be performed. The design of the control system to maintain desired environmental conditions is essential to proper operation of the facility. A simulation model of the facility has been developed by analyzing each component of the system thermodynamically with necessary properties and heat transfer relations. Using the system simulation model, the required characteristics of the control system has been investigated. PI controller is considered as the most probable controller for this kind of the facility, and electric heater power is shown as the Proper manipulated variable for temperature control.

• International Journal of Air-Conditioning and Refrigeration
• /
• 제8권1호
• /
• pp.62-72
• /
• 2000

Environmental control facilities are used to simulate an environment or combination of environments under which many kinds of research and tests can be performed. The design of the control system to maintain desired environmental conditions is essential to proper operation of the facility. A simulation model of the facility has been developed by analyzing each component of the system thermodynamically. with necessary properties and heat transfer relations. Using the system simulation model, the required characteristics of the control system has been investigated. PI controller is considered as the most probable controller for this kind of the facility, and electric heater power is shown as the proper manipulated variable for temperature control.

• Environmental Engineering Research
• /
• 제19권2호
• /
• pp.165-174
• /
• 2014

A model combining multi-dimensional discretized population balance equations with a computational fluid dynamics simulation (CFD-DPBE model) was developed and applied to simulate turbulent flocculation and sedimentation processes in sediment retention basins. Computation fluid dynamics and the discretized population balance equations were solved to generate steady state flow field data and simulate flocculation and sedimentation processes in a sequential manner. Up-to-date numerical algorithms, such as operator splitting and LeVeque flux-corrected upwind schemes, were applied to cope with the computational demands caused by complexity and nonlinearity of the population balance equations and the instability caused by advection-dominated transport. In a modeling and simulation study with a two-dimensional simplified pond system, applicability of the CFD-DPBE model was demonstrated by tracking mass balances and floc size evolutions and by examining particle/floc size and solid concentration distributions. Thus, the CFD-DPBE model may be used as a valuable simulation tool for natural and engineered flocculation and sedimentation systems as well as for flocculant-aided sediment retention ponds.

• 국제학술발표논문집
• /
• The 5th International Conference on Construction Engineering and Project Management
• /
• pp.226-230
• /
• 2013

In the tall building construction, the slab formwork largely impacts on construction cost. Because productivity of a slab formwork is influenced by a number of and the efficiency of equipment, using the equipment-based construction method, an appropriate equipment input planning is crucial for the productivity. Meanwhile, the general equipment input planning is conducted by intuition based on experience due to the lack of equipment productivity data. Thus, this study develop a simulation model to analyze table formwork productivity and to propose an optimum equipment input plan that reflects the construction process, based on the full consideration of the economic factors. This study developed a simulation model by using CYCLONE and the data for the model was collected by measuring the duration of each unit activity in the tall building where table forms were applied. It is expected that a simulation model helps users to make better decision on the equipment input planning of slab formwork.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2012년도 추계학술대회 논문집
• /
• pp.147-152
• /
• 2012

An instantaneous environmental noise simulation method emitted by a moving high-speed train by quasi-stationary analysis is proposed in this study. In the method, the propagation attenuations from stationary point sources on segmented railways to a receiver are calculated using a general purpose environmental noise prediction program ENPro based on the ISO 9613-2 method. Then, the instantaneous environmental noise at a receiver due to a moving high-speed train considering convection effect is evaluated with the information on the propagation attenuations from the instantaneous train location to the receiver and the sound power levels and directivity of stationary point sources evaluated by German Schall 03 (2006). To demonstrate the validity of proposed method, simulated and measured time history of instantaneous noise for KTX-I and KTX-II on running are compared and the results show that the method can be utilized for the train noise source identification as well as the simulation of instantaneous environmental noise emitted by a high-speed train.