• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.198-202
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• 1987

The regulator problem can be considered as some impulsive disturbance rejection one. In this point of view, the rate of decay is one of important factors for regulation and depends on how negative the real parts of the eigenvalues of closed-loop system. The algorithm that the closed-loop system has eigenvalues lying within a vertical. strip is useful for rapid disturbance rejection. This paper presents a design method for a linear quadratic regulator of two-time scale system with eigenvalues in a vertical strip by use of time-scale separation property.

• Journal of applied mathematics & informatics
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• v.18 no.1_2
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• pp.621-637
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• 2005

A hybrid method solving regularized structured linear total least norm (RSTLN) problems, which have highly ill-conditioned coefficient matrix with special structures, is suggested and analyzed. This scheme combining RSTLN algorithm and separation by parts guarantees the convergence of parameters and has an advantages in reducing the residual norm and relative error of solutions. Computational tests for problems arisen in signal processing and image formation process confirm that the presenting method is effective for more accurate solutions to (R)STLN problem than the (R)STLN algorithm.

• Proceedings of the Korean Society of Rheology Conference
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• 2006.06a
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• pp.71-74
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• 2006

• Resources Recycling
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• v.12 no.3
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• pp.25-30
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• 2003

The synthesis of SiC used for the parts of the gas turbine and the heat exchanger, was carried out. In this study, wire cutting slurry of silicon wafer and the graphite rod of spent zinc-carbon battery were applied to the starting materials for the synthesis. The powders of Si or Si+SiC were obtained from the waste material by filtration, gravity separation and magnetic separation. Graphite powder was produced by dismantling, grinding and gravity separation from spent zinc-carbon battery. The synthesis of SiC could be completed from the mixture powders of Si and C or Si+SiC and C at the condition of equivalent ratio of Si and C, atmosphere of Ar or vacuum, temperature of above 1$600^{\circ}C$ and 2 hours reactions. The purity of synthesized Si-C was above 99%.

• Journal of Animal Environmental Science
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• v.2 no.1
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• pp.79-86
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• 1996

Solid/Liquid(S/L) separation is crucial for biological treatment of animal wastewater. Liquid portion from S/L separation has less BOD-load and proper post-strip treatment can be obtained. Screen or declined sieve was normally used to separate the solid parts. For better separating efficiency a vibration and a cylindrical separator were constructed and tested. The results are summarized as follows; Solids removal efficiency and moisture content of separated solid were 15~26% and 85~88%, respectively for the vibration separator. for the cylindrical separator, solid removal efficiency and moisture content of solid were 16~39% and 86~89%, respectively. The greatest amount of drymatter was obtained when operating vibration separator with 10$^{\circ}$ inclination and 100% vibrating power. For the cylindrical separator maximum efficiency was obtained with 40 rpm and 19$^{\circ}$ inclination. The vibration and the cylindrical separator have shown 21% and 26% in BOD removal, respectively. These two types of separator were proved to be applicable methods for animal wastewater separation.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.04a
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• pp.222-225
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• 2009

The apartment housing in Korea has been rapidly constructed by adapting the most suitable construction methods as like wall structure, wet and united construction. But most of short-lived equipments usually filled in the structure which has longer life, and it causes not only to make difficult coping with the deterioration of equipments but also to let buildings remained deteriorate themselves. The buildings can be remodelled to slow down the terms of deterioration or reconstructed to give a new life of themselves, although the disposal of wastes or the lack of natural resources still be problems and unsolved that can occurred in pulling down and reconstructing the buildings. Furthermore, it is the time to need keeping with worldwide trends and movements as like sustainability or 'green growth' movements based on low carbon emissions. The researches for Long-Life Housing apartments which has durability and variation have been advanced up to now. Long-Life Housing apartments can separate their structures from equipments and interior or exterior materials of buildings. Therefore equipments or materials of buildings can be easily repaired and replaced with new ones, even if they are deteriorated themselves. Also, the construction process of Long-Life Housing apartments can be independent from the matter of proprietary rights, terms of durability, decision rights and so on. 'The law of Possession and Management of Collective Building' and the 'Regulation of Management of Collective Building' established by each local governments are already legislated for declaring the rights of using and ownership, responsibilities of each parts of apartment buildings. These laws and regulations classify the ownership of each parts of apartment buildings, and divide the ownership with public possession and exclusive possession. Therefore, this study will conduct comparative analysis between 'The law of Possession and Management of Collective Building' and 'the Regulation of Management of Collective Building' and find problems which can be occurred in future construction of Long-Life Housing apartments. It will be helpful to revise laws and regulations.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.457-460
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• 2000

Injection molding is the most widely used process for the industrial forming of plastic articles. During an injection molding process of composites, the fiber-matrix separation and fiber orientation are caused by the flow of molten polymer/fiber mixture. As a result, the product tends to be nonhomogeneous and anisotropic. Hence, it is very important to clarify the relations between separation·orientation and infection molding conditions. So far, there is no research on the measurement of fiber orientation using image processing. In this study, the effects of fiber content ratio and molding condition on the fiber orientation-angle distributions are studied experimentally. Using the image processing method, the fiber orientation distribution of welding parts in injection-molded products is assessed. And the effects of fiber content and injection mold shapes on the fiber orientation in case of fiber reinforced polymeric composites are studied. experimentally.

• Resources Recycling
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• v.27 no.2
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• pp.3-10
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• 2018

In this paper, Proposed bonding mechanism that can separate sole and upper for recycle and reuse of parts. It was confirmed that the PVC film with better physical properties than the existing parts was inserted between the sole and the upper. It was confirmed that the separation of the desired form can be induced. As a result of checking the performance of the proposed mechanism, it is confirmed that intentional separation is possible and the separated sole and upper can be recycled or reused.

• The Journal of Engineering Geology
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• v.32 no.4
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• pp.725-733
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• 2022

This study applied a hydraulic rock splitting system equipped with a hybrid packer to the bench-cut method. The hybrid packer system is an improvement of the packer developed in previous studies; it is designed efficiently to reduce vibration and noise during rock excavation by combining the two functions of inducing hydraulic fractures using injection pressure and then expanding and extending them using a rubber packer. Field experiments assessed the efficiency of rock excavation with respect to the injection conditions; the adjusted experimental conditions included the distance from the free surface and the test holes drilled at the top of the slope and the injection settings. Using a separation of 5 m left some unexcavated parts, but using a separation of 1 m left no unexcavated parts. The hydraulic fractures generated by the injection pressure developed generally parallel to the free surface and expanded and extended as the rubber packer expanded, thus facilitating bench-cut excavation. For hydraulic rock splitting to be broadly applicable to bench-cut rock excavation, it is important to accumulate results from many field experiments conducted under varying experimental conditions for various types of rockmass.

• Resources Recycling
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• v.20 no.3
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• pp.68-76
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• 2011

For the separation of aluminum and iron from platinum mixtures, extraction resins were synthesized and separation efficiencies were compared with those by commercial one, $P_{204}$. During synthesis, the suspension polymerization method was adopted with D2EHPA as an extractant. Also, benzoyl peroxide as a starter was divided into 3parts and injected for the uniform size and dispersion of resin particles. Comparison tests resulted in 100% separation of Fe and Pt for both synthetic and $P_{204}$ resins. In case of Al and Pt, synthetic and $P_{204}$ resin gave extraction efficiencies of 99.9% and 98.9%, respectively. Difference in extractant contents of synthetic resin(61.8%) and $P_{204}$(60%) was considered to give differences in separation efficiencies of aluminum and iron elements. For both resins, separation efficiencies of Al and Fe increased up to $55^{\circ}C$. According to FT-IR analyses of both resins, specific peaks of D2EHPA and crosslinked polystyrene were identified at the wavenumber of $1000cm^{-1}$ and $2900cm^{-1}$ respectively.