• Journal of architectural history
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• v.14 no.2 s.42
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• pp.71-88
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• 2005

This study aims at clarifying the spatial generative process of Borromini's architecture. The close examination of his sketches and the analysis of his major four works such as San Carlo alle Quattro Fontane (1634-1667), Sant'Ivo della Sapienza (1642-1660), Santa Maria dei Sette Dolori, Chapel (1643-1646), Collegio di Propaganda Fide, Chapel (1652-1667) show common features in the generation of space as follow. 1) The spatial generative process of Borromini's architecture is dominated by the plan of main space which is formulated from simple geometric elements into complexly folded space by mean of union, addition, copy and warping. 2) Borromini made various kinds of annexed space around the main space to create long and continuous circulation. 3) Borromini's architecture has a tendency to divide interior elevation into two parts, wall part and roof part by thick entablature. Moreover the entablature play important role to copy the figure of the plan of main space three-dimensionally. 4) Borromini tried to create the sense of depth through perspectival distortion and multi-focal space through the ceiling pattern.

• Journal of Wetlands Research
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• v.10 no.2
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• pp.1-14
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• 2008

This study was to describe the ecological survey of wetland plants from Sinbul Mt. and suggest the ways of the sustainable ecological management and wise use. We found 167 plant species. Molinia japonica HACK was the most dominant species and Asarum maculatum NAKAI, Drosera rotundifolia L. and Utricularia racemosa WALL were considered as the most important species. Thus, it was concluded that this area need strong conservation due to the necessity for species diversity. Such several management schemes as the designation for national wetland conservation area, continuous monitoring, cautious surveillance and wise management were suggested to implement successful conservation.

• 한국전산유체공학회:학술대회논문집
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• 2005.10a
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• pp.293-298
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• 2005

We calculate the coordinates of an axisymmetric nozzle with a central body. This nozzle ensures a transonic flow with a plane sound surface, which is orthogonal to the symmetry axis and has a wall kink at the sonic point, The Chaplygin transformation in the subsonic part of the flow leads the Dirichlet problem for a system of nonlinear equations. The definition domain of the solution in the velocity-hodograph plane is taken as a rectangle. This enables one to obtain the nozzle with a monotonic distribution of velocity along its subsonic part. In the nonlinear differential equation, the linear Chaplygin operator for plane flows is separated, which allows the iterative calculation of the solution. The supersonic part of the nozzle is calculated under the assumption that the flow at the nozzle exit is uniform and parallel to the symmetry axis; i.e., the supersonic jet outflows to the submerged space with the same pressure. The calculation is performed by the characteristic method. The exact solution of Tricomi equation for near-sonic flows with the straight sonic line is used to 'move away' the sound plane. The velocity distribution alone the supersonic part of the nozzle is also monotonic, which ensures the absence of the boundary-layer separation and, therefore, the adequacy of the ideal-gas model. calculations show that the flow in the supersonic part of the nozzle is continuous (compression shocks are absent)

• Journal of Microbiology and Biotechnology
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• v.1 no.3
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• pp.212-219
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• 1991

Four species of yeast, Saccharomyces cerevisiae, Candida utilis, Saccharomycopsis flbuligera, and Schwanniomyces castellii were evaluated for their ability to bioconvert potato processing waste water into microbial protein and the resulting single-cell proteins were evaluated as protein sources for rainbow trout, using in vitro analyses. The studies indicated that Schwanniomyces castellii, which utilizes starch dircetly and converts it into cell mass efficiently, was suitable for the bioconversion. In the single-stage continuous bioconversion, the yield S. castellii cell mass, which contained approximately 37% protein, was 77%, at dilution rate 0.25 $h^{-1}$. Reduction of total carbohydrate was 81%. During batch fermentations, cell mass yield was about 72% and total carbohydrate reduction was 81%. Among the yeasts tested, S. castellii possessed the most fragile cell wall and had a favorable amino acid profile for salmonid fish; protein score of 86% (Met). In an in vitro pepsin digestibility test 80% digestibility (23~38% above control) was observed when cells were pre-heated in a steam bath for 30 min. Results presented should be regarded as being preliminary in nature because they were derived from single experiments.

• Journal of Korean Society on Water Environment
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• v.33 no.2
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• pp.187-196
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• 2017

To ensure hygienic safety of drinking water in a water storage tank, the concentrations of residual chlorine should be above a certain regulation level. In this study, we conducted model simulations to investigate the effects of temperature on residual chlorine in water storage tank conditions typically used in Seoul. For this, values of model parameters (decomposition rate constant, sorption coefficient, and evaporation mass transfer coefficient) were experimentally determined from laboratory experiments. The model simulations under continuous flow conditions showed that the residual chlorine concentrations were satisfied the water quality standard level (0.1 mg/L) at all the temperature conditions ($5^{\circ}C$, $10^{\circ}C$, $15^{\circ}C$, $20^{\circ}C$ and $25^{\circ}C$). Meanwhile, when the tanks had a no flow condition (i.e., no tap-water influent due to a sudden shut-down), the concentrations became lower than the regulatory level after certain periods. The findings from this modeling works simulating Seoul's water storage tanks suggested disappearance rate of residual chlorine could be reduced through the tanks design optimization with maintenance of low water temperature, minimization of air flow and volume, suppression of dispersion and the use of wall materials with low sorption ability.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.612-615
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• 1996

In the continuous casting process, molten metal contacts the mold wall and the molten metal surface is subject to the mold oscillation. The mold oscillation results in the oscillation marks on the surface of solidified steel, which has undesirable effects on the quality of slabs. In order to reduce the oscillation marks by achieving soft contact of molten metal with the mold surface, alternating magnetic field is applied to the surface of molten metal. However, if the magnetic field strength becomes too strong, the melt flow induced by the magnetic field. causes the instability of the molten metal surface, which has also the bad influence on the slab quality. Therefore, it is very important to choose the optimal position of the inductor coil and the optimal level of electric power to minimize the surface defects. In the present work, as a first step toward the optimization problem of the process, numerical studies are performed to investigate the effects of coil position and the electric power level on the meniscus shape and the flow field. As numerical tools, the boundary integral equation method(BIEM) is used for the magnetic field analysis and the finite difference method (FDM) with orthogonal grid generation is used for the flow analysis.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.7
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• pp.293-298
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• 2016

A three-dimensional (3D) numerical model of the vertical ground-coupled heat exchanger is useful for analyzing the modern ground source heat pump system. Furthermore, a detailed description of the inner side of the exchanger allows to account for the effects of the thermal capacity. Thus, both methods are included in the proposed numerical model. For the ground portion, a FDM (Finite Difference Method) scheme has been applied using the Cartesian coordinate system. Cylindrical grids are applied for the borehole portion, and the U-tube configuration is adjusted at the grid, keeping the area and distance unchanged. Two sub-models are numerically coupled at each time-step using an iterative method for convergence. The model is validated by a reference 3D model under a continuous heat injection case. The results from a periodic heat injection input show that the proposed thermal capacity model reacts more slowly to the changes, resulting in lower borehole wall temperatures, when compared with a thermal resistance model. This implies that thermal capacity effects may be important factors for system controls.

• Journal of the Korea Concrete Institute
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• v.16 no.2 s.80
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• pp.283-291
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• 2004

Recently, the construction of underwater structures has been gradually increased, but underwater concrete got some problems of quality deterioration and water contamination around cast-in-situ of construction. In addition, massive underwater structures such as LNG tank, underwater concrete structures of large and continuous high- strength subterranean wall under water are being demanded lower heat of hydration. In this paper, the mechanical properties of high-strength antiwashout underwater concrete (HAWC) containing with two kinds of mineral admixtures respectively were investigated. On the basis of these results, the pH value and suspended solids of HAWC manufactured in the mock-up test were 10.0$\Box$11.0 and 51 mg/${\iota}$ at 30 minutes later, respectively, initial and final setting time were about 30,37 hours, and the slump flow was 530$\pm$20Tm. In the placement at a speed of $27 m^3/hr$, there was no large difference in flowing velocity with or without reinforcing bar, and flowing slope was maintained at horizontal level. Compressive strength and elastic modulus of the cored specimen somewhat decreased as flowing distance was far; however, those of central area showed the highest value.

• Journal of Energy Engineering
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• v.12 no.2
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• pp.131-138
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• 2003

This paper considered the structural mechanism of transitional boundary layer by the experimental approach. In order to measure the turbulence quantity in the boundary layer, we made a wind tunnel with 400${\times}$190${\times}$2500 mm test section and a flat plate with well fabricated leading edge. Hot wire anemometer was used for acquiring the continuous turbulence signal which is processed by special software. The results of experiment show that the region where turbulence spot is dominant moves from near wall to overall layer and thus the anisotropy of velocity fluctuation shows so large value. Also the turbulence energy originally contained in low frequency band comes up to the high frequency band. Finally the turbulence model needs minimum two length scales to consider the pre-transition region.

• Journal of Trauma and Injury
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• v.29 no.2
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• pp.37-42
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• 2016

Purpose: Arterial injury in children is a challenging problem for its special characteristics. It is rare even during warfare. This review described a personal experience in the management and outcome of acute pediatric arterial injuries of extremities. Methods: Thirty-six children below age of 13 years were studied during period from 2004 through 2014 in Iraq. Results: Male patients were 27 (75%) and female were 9 (25%). Seven to twelve years old was the most affected age group. The incidence of iatrogenic injuries was greater in infants and toddlers while penetrating injuries were the most common in older children. Upper limbs arteries were affected in 17 (47.2%) and lower limb in 19 (52.8%) patients. Hard signs were the commonest mode of presentation (83.3%). Lateral wall tear and complete transection were the most frequent types of arterial injury (36.1% and 27.8% respectively). The most frequent procedures performed were end-to-end anastomosis and lateral arteriorrhaphy. Surgical outcome was good. In 27 cases distal pulsations were regained. Seven cases had impalpable distal pulses but still viable limbs. Limb length discrepancy was detected in one case. One case was complicated with limb loss. No death was recorded. Conclusion: Arterial injuries in children are age related. The proper treatment of arterial injuries in children requires high index of suspicion, early operative intervention and continuous postoperative follow-up throughout years of active growth. Angiogram has a limited role as a diagnostic tool in acute arterial injuries.