• Journal of Korean Society on Water Environment
• /
• v.34 no.2
• /
• pp.226-233
• /
• 2018

Small-scale wastewater discharge facilities account for 98% of all workplaces, but in the generation and emission of major pollutants, they account for 27.5 % and 23.5 %, respectively. Since the proportion of the emission load of the small-scale workplace is not large, the national environmental policy has been established mainly around large-scale wastewater discharge facilities. However, in the case of specific hazardous substances in water, the amount of the discharge load of the small-scale wastewater discharge facility was 2.4 times higher than that of the generation load. Certain types of specific hazardous substances in water, which have a higher discharge load than large-scale wastewater discharge facilities, account for 24 ~ 32 %. There are also cases in which the discharge load from a small-scale discharge facility is more than four times higher, depending on the specific kind of water pollutant. As a result of inspections, the violation rate of the small-scale wastewater discharge facility among the total violations by facilities is 93.9 ~ 97.5 %. As a result, the ecotoxicity value of small-scale wastewater discharge facilities was high in most industries, and there was a fluctuation in the measured value. This indicates that the ecological integrity of the water system can be largely influenced by small-scale wastewater discharge facilities. Therefore, it is necessary to expand the environmental management of small-scale wastewater discharge facilities, and in some cases, the effect of the improvement in quality may be more significant than in the management of large-scale wastewater discharge facilities.

• Interaction and multiscale mechanics
• /
• v.5 no.1
• /
• pp.27-40
• /
• 2012

The two-dimensional incompressible flow of a linear viscoelastic fluid we considered in this research has rapidly oscillating initial conditions which contain both the large scale and small scale information. In order to grasp this double-scale phenomenon of the complex flow, a multiscale analysis method is developed based on the mathematical homogenization theory. For the incompressible flow of a linear viscoelastic Maxwell fluid, a well-posed multiscale system, including averaged equations and cell problems, is derived by employing the appropriate multiple scale asymptotic expansions to approximate the velocity, pressure and stress fields. And then, this multiscale system is solved numerically using the pseudospectral algorithm based on a time-splitting semi-implicit influence matrix method. The comparisons between the multiscale solutions and the direct numerical simulations demonstrate that the multiscale model not only captures large scale features accurately, but also reflects kinetic interactions between the large and small scale of the incompressible flow of a linear viscoelastic fluid.

• The Bulletin of The Korean Astronomical Society
• /
• v.38 no.2
• /
• pp.61.1-61.1
• /
• 2013

Turbulence is a common phenomenon in astrophysical fluids such as the interstellar medium (ISM) and the intracluster medium (ICM). In turbulence studies it is customary to assume that fluid powered by an energy injection on a single scale. However, in astrophysical fluids, there can be many different driving mechanisms that act on different scales simultaneously. In this work, we assume multiple energy injection scale (2${\surd}$12 and 15

• Journal of Internet Computing and Services
• /
• v.10 no.6
• /
• pp.205-217
• /
• 2009

Recently, many organizations such as companies or institutions have demanded induction of very large-scale workflow management system in order to process a large number of business-instances. Workflow vendors have focused on physical extension of workflow engines based on device-level clustering, so as to provide very large-scale workflow services. Performance improvement of workflow engine by simple physical-connection among computer systems which don't consider logical-level software architecture leads to wastes of time or cost for construction of very large-scale workflow service environment. In this paper, we propose workcase-based workflow architecture and implement a very large-scale workflow management system based on the architecture. We prove that software architectures to be applied on a workflow engine have an effect on scalability and performance through workcase response-time evaluation of our proposed system.

• 제어로봇시스템학회:학술대회논문집
• /
• 1986.10a
• /
• pp.550-553
• /
• 1986

This paper presents a procedure for the time-scale separation and a design method for the sub-optimal composite regulator and Kalman filter of the large-scale discrete stochastic system with two time-scale properties. Provided that the fast sub-system is asymptotically stable, the reduced-order regulator and Kalman filter for the slow sub-system with dominant modes is designed as a sub-optimal regulator for the system.

• Korean Institute of Interior Design Journal
• /
• v.18 no.5
• /
• pp.191-199
• /
• 2009

Recently general hospitals in Korea are focusing on healing environment which care for patients on the side of spirit and psychology without medical treatment. For the reason, architects are planning a public space on a large scale in which can be held cultural performances and artistic events. Those of social activities can be effective healing environment according to the "Anthroposophical medicine" studied by Rudolf Steiner. To the patient, Social healing environment is relation with normal life and back to the life. The case of a large-scale public space on hospital in foreign country shows the effect of healing environment through social community. So it is valuated as a social healing environment and community space. Even though the large-scale public space has been being increased in our circumstance, there is no evaluation of use on it. So there is no idea how people are satisfied with public space to stay and form a concourse by themselves. The purpose of this study is to find out the desire of people, who use the large-scale public space by analysis of observation research and interview in the general hospitals. And finally this study suggests the factors which can realize social healing environment on the planning of public space in hospital architecture.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.48 no.6
• /
• pp.781-788
• /
• 1999

In this paper, an expert system is proposed, which can be effectively applied to the large-scale systems with the diversity time constraints, the objectives and the unfixed system structure. The inference scheme of the expert system have the integrated structure composed of the intuitive inference module and logical inference module in order to support effectively the operating constraints of system. The intuitive inference module is designed using the pattern matching or pattern recognition method in order to search a same or similar pattern under the fixed system structure. On the other hand, the logical inference module is designed as the structure with the multiple inference mode based on the heuristic search method in order to determine the optimal or near optimal control strategies satisfing the time constraints for system events under the unfixed system structure, and in order to use as knowledge generator. Here, inference mode consists of the best-first, the local-minimum tree, the breadth-iterative, the limited search width/time method. Finally, the application results for large-scale distribution SCADA system proves that the inference scheme of the expert system is very effective for the large-scale system. The expert system is implemented in C language for the dynamic mamory allocation method, database interface, compatability.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.22 no.3
• /
• pp.316-325
• /
• 1998

The objective of this study is to investigate the role of large-scale coherent structures in a spatially developing plane mixing layers. To achieve this, we have to look into the mutual interactions between three-dimensional large-scale coherent structures and the mean flow. Our attention will be focused on the energy exchange mechanism between the various modes, and the effects of the nonlinear evolution of the phases of the interacting modes. Linear stability of the three-dimensional viscous shear layer is formulated and solved as the basis for the solution of the nonlinear formulation based on the energy method. The importance of the initial conditions that may affect the evolution of the flow has been examined. It has been numerically calculated the nonlinear effects arising from the interactions among the three-dimensional large-scale coherent structures in a spatially developing plane mixing layers. The results of this study provide useful parametric information for the control of shear layer in practical applications in the mixing and transport augmentation.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.11 no.4
• /
• pp.147-153
• /
• 2012

The demands of the large scale machine tools, for instance, such as planomiller, turning machine, boring machine, NC machine, have been gradually increased in recent years. As the performances of machine tools and/or cutting tools are advanced, it is possible to perform high-speed and high-precision cutting works. The effective treatment of wet chip, which is discharged from cutting works, becomes very important problems. Therefore, this study is forced on the design of large scale machine tools using CATIA V5R18 and analysis of cutter, which is considered as essential equipment in large scale machine tools, using MSC.Nastran & MSC.Patran. Especially, the relations between tolerated load of cutter, driving horse power and rpm of driving shaft in chip processing system are investigated through analysis. As the results, the reliability of design could be improved by evaluating simulated numerical values, it showed that tolerated loads of supported part and edged part of cutter are 87,000N and 14,450N, respectively.

• Journal of Environmental Impact Assessment
• /
• v.22 no.1
• /
• pp.79-87
• /
• 2013

The purpose of this study is to establish PM-10 management manual for developing large scale sites by assessing the status of PM-10 reduction at ongoing large scale development sites. After analyzing the meteorological conditions and air quality characteristics of Sihwa MTV development site, ISCST3 (Industrial Source Complex Short Term Model 3) was implemented to predict PM-10 generation. The outcomes of ISCST3 modelling were utilized for verification of site survey data. As a result of applying air pollution modeling, the diffusion rate of PM-10 decreases according as the wind speed decreases. And the emission rate of PM-10 increase is linear to the concentration of PM-10. The reduction target of PM-10 can be derived quantitatively from the difference between the forecasted emission rate and the permissible emission limit of PM-10. The assessment of PM-10 characteristics which is deduced from ISCST3 and site survey can be practically applied to accomplish environmentally acceptable air quality manual for large scale development sites.