• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.804-807
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• 2006

Bacterial serine proteases, especially those from Bacillus, have been extensively studied. Intracellular serine protease 1 (Isp1) is responsible for most of the proteolytic activity in B. subtilis. To identify Isp1 substrates and study its physiological functions, a mutant of Isp1, which has lost the enzymatic activity, was constructed. Through a GST affinity chromatographic method, several Bacillus proteins that specifically interacted with S246A mutant Isp1 protein were isolated and then identified by MALDI-TOF analysis. ClpC and elongation factor Tu (EF-Tu) were among those proteins specifically bound to mutant Isp1. In addition, several proteins involved in stationary phase adaptive response (such as RNA polymerase sigma factor, spoIIIE) were also identified. These findings led us to suggest that the major function of this serine protease, whose expression is greatly increased during the stationary phase, is to mediate transition of the cell into the stationary phase in a proper and timely manner.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.4
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• pp.397-400
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• 1995

Effects of rheological parameters, such as shear rate, temperature, concerntration, salts on the apparent viscosity of chitosan(deacetylation degree: $84\%$, Mw: 267,000) dissolved in acetate buffer(pH 4.5) were investigated. Rheologiral properties of chitosan solution from cuticle of red snow crab (Chinonecetes japonicus) are as follows. $0.5\%$ chitosan in 0.1M acetate buffer (pH 4.5) solution showed Bingham flow having hysteresis loop. It's flow equation was $\sigma=0.757+19.6_\gamma(r^2=0.99)$. The viscosity of chitosan solution is exponentially increased with its concentration, and showed Arrhenius dependence with respect to the temperature $(10^{\circ}C-40^{\circ}C).$ When various salts were added to chitosan solution, the viscosity decreased as the concentration of counterion increased. But the type ot counterions itself does not have any significant effects on the viscosity.

• Korean Journal of Construction Engineering and Management
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• v.9 no.6
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• pp.194-203
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• 2008

Construction companies require management system to increase efficiency and profit because of receiving competition and globalizing business environment. Since 1990s, construction companies have made various attempts to innovate business structure both internally and externally by means of BPR, 6 Sigma, PI, and Workflow. Some improvements were made, but most of them were temporary, and insufficient to provide the much-needed promptness of business process in responding to the changes. Furthermore, the recent methods of applying BPM and practical using are limited to the theory and method of other industries, and also the attempts of applying BPM in construction industry are at the stage of theoretical approaching and examining in a few construction companies. Accordingly, this study deduces the necessity of adopting BPM based on change of business paradigm for construction companies and limits of current researches, failure causes and problems of application attempts of BPM and process management. And also, we analyze Advance of BPM and suggest the application method of business process management model for construction companies.

• Fashion & Textile Research Journal
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• v.10 no.5
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• pp.660-667
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• 2008

The purpose of this study was to modify a Flared Skirt for women according to the somatotype of lower body. The subjects for the wear test were 3 students, who were in $mean{\pm}1{\sigma}$ each somatotype. The results of this study are as follows: First, the Flared Skirt pattern was modified according to each type. The front waist line rising measurement proposed for type 1 and type 2 were 0.5cm, because of lower front silhouette with waist shape. The back waist line rising measurement proposed for type 2 was 1cm and type 3 was 0.5cm, because of lower back shape with hip. Second, the wave-height of nodes were regular at front and back in type 1. Also, the wave-height of nodes were evenly distributed side and center. The variation ratio of wave-height of back nodes were lower than existing pattern in type 2 and type 3. It means the variation ratio of wave-height of back nodes were regular in modification pattern. Altogether, modification patterns were more regular and lower than existing pattern in the number of nodes, the distribution ratio of nodes, the wave-height of node, the variation ratio of wave height of nodes.

• Journal of Korean Society on Water Environment
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• v.33 no.4
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• pp.449-459
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• 2017

In Geum River of Korea, three multi-purpose weirs were built at the downstream of Daecheong Reservoir during the Four Major River Restoration Project (FMRRP). The weirs have altered the hydraulic characteristics of the river, and consequently transformed the large areas of flowing ecosystem to deep and wide stagnant environment. In every summer, a thermal stratification occurred near the Baekje Weir having mean depth of 4.0 m, and the surface algal blooms dominated by buoyant cyanobacteria have been frequently formed after the FMRRP. The objective of this study was to investigate the relationship between flow velocity and thermal stability of the waterbody using a three-dimensional (3D) hydrodynamic model (EFDC+) after calibration against the thermistor chain data obtained in 2014. A new Sigma-Zed vertical grid system of EFDC+ that minimize the pressure gradient errors was used to better simulate the thermodynamics of the waterbody. The model reasonably simulated the vertical profiles of the observed water temperatures. The vertical mean flow velocity and the Richardson Number (Ri) that represents the stability of waterbody were estimated for various management water levels and flow rates scenarios. The results indicated that the thermal stability of the waterbody is mostly high ($Ri{\gg}0.25$) enough to establish stratification, and largely depend on the flow velocity. The critical flow velocity that can avoid a persistent thermal stratification was found to be approximately 0.1 m/s.

• Fire Science and Engineering
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• v.13 no.2
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• pp.26-32
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• 1999

We had investigated combustion pro야$\pi$ies of rice bran dusts. Decomposition of rice bran d dusts with temperature were investigated using DSC and the weight loss according to t temperature using TGA in order to find the thermal hazard of rice bran dusts, and the p properties of dust explosion in variation of their dust with the same particle size. Using H Hartman's dust explosion apparatus which estimate dust explosion by electric ignition after m making dust disperse by compressed air, dust explosion experiments have been conducted by v varying concen$\sigma$ation and size of rice br뻐 dust. According to the results for thermodynamic stability of rice bran dust, there are little change of initiation temperature of heat generation 때d heating value for used particle size. But i initiation temperature of heat generation decreased with high heating rate whereas d decomposition heat increased with particle size. Also, the explosion pressure was increased as t the ignition energy increased and average maximum explosion pressure was 13.5 kgv'cnt for 5 BJ/60 mesh and 1.5 뼈Ie미 dust concentration.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.5
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• pp.722-730
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• 2001

The local heat transfer of an axisymmetric submerged air jet impinging on a heated flat plate is investigated experimentally with the variation of mesh-screen solidity. The screen installed in front of the nozzle exit modifies the flow structure and local heat transfer characteristics. The mean velocity and turbulence intensity profiles of streamwise velocity component are measured using a hot-wire anemometry. The temperature distribution on the heated flat surface is measured with thermocouples. The smoke-wire flow visualization technique was employed to understand the near-field flow structure qualitatively for different mesh screens. Large-scale toroidal vortices and high turbulence intensity enhance the heat transfer rate in the stagnation region. For a higher solidity, turbulence intensity become higher which increases the local heat transfer at small nozzle-to-plate spacings such as L/D<6. The local and average Nusselt numbers of impinging jet from the $\sigma$(sub)s=0.83 screen at L/D=2 are about 5.6∼7.5% and 7.1% larger than those for the case of no screen, respectively. For the nozzle-to-plate spacings larger than 6, however, the turbulence intensities for all tested screens approach to an asymptotic curve and the mean velocity along the jet centerline decreases monotonically. As the nozzle-to-plat spacing increases for high solidity screens, the heat transfer rate decreases due to the reduction in turbulence intensity and jet momentum.

• Journal of Korean Society of Steel Construction
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• v.15 no.3
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• pp.291-298
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• 2003

Recently, as the size of buildings structure becomes large increases, their mat area of building structure is supported or by an inhomogeneous foundation. This paper presents a vibration analysis on thick plates subjected to in-plane force is presented in this paper. The rectangular plate is isotropic, homogeneous, and composed of a linearly elastic material. A vibration analysis of the rectangular thick plate iwas done by useing ofarectangular finite element with 8 nodes and 9 nodes. In this study, the foundation was idealized as a Pasternak foundation model. A Pasternak foundation haves a shear layer on Winkler's model, which idealizes the foundation as a vertical spring. In order tTo analysze the vibration of a plate supported on by an inhomogeneous Pasternak foundation, the value of the Winkler foundation parameter of the central and border zones of the plate awere chosen as WFP1 and WFP2. (fFigure 4.). The Winkler foundation parameter of WFP1 and WFP2 is varied from 0 to 10, $10^2$, and $10^3$ and the shear foundation parameters is were 0, 5, and 10. The ratio of the in-plane force to the critical load iwas applied as 0.4 to 0.8

• Fire Science and Engineering
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• v.13 no.1
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• pp.3-10
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• 1999

We had investigated combustion properties of natural textile dusts. Decomposition properles of natural textile dusts scavenged by precipitator of spinning factoη were investigated using D DSC(Differential Scanning Calorimeter) and TGA(Thermogravimetric Analysis) by temperature c changes. Combustion pro야rties of natural textile according to size distribution and amount were c checked as temperature variation according to time using spontan$\infty$us ignition apparatus. M Moreover, combustion properties with blowing or without blowing condition were checked in order to investigate combustion prope$\pi$ies in spontaneous ignition apparatus according to flow c condition of air. As results of thermal analyses, increase in r머sing tern야:rature causes initial smold벼ng t temperature to move towards low temperature section 뻐d i띠디떠 smoldering temperature was d de$\sigma$eased more remarkably in atmosphere than in inert gas and that condition allowed heating v value to increase considerably. In addition, as amount and size distribution of natural textile d dusts were increased, i띠ti머 smoldering temperature was lowered. All of combustion forms were s smoldering combustion. Initial smold밍ing temperature was low more slightly with blowing c condition than without blowing condition in sp$\alpha$ltaneoUS ignition apparatus, which condition m made heatim;!; value high.

• Transactions of Materials Processing
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• v.8 no.3
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• pp.247-247
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• 1999

The segregation (distribution) of nickel and the composition of its constituents influence the low thermal expansion characteristics (Invar effect) in Fe-30 wt.% Ni-12.5 wt.% Co-xC Invar alloy. The change of coefficient of the thermal expansion and magnetic properties were studied as an aspect of carbon addition causing the segregation of Ni in primary austenite of as-cast Fe-30 wt.% Ni-12.5 wt.% Co Invar alloy. The coefficient of thermal expansion of Fe-30 wt.% Ni-12.5 wt.% Co-xC Invar alloy showed its lowest value at 0.08 wt.% carbon, increased with increasing carbon content in the range of 0.08-1.0 wt.%C, kept constant at 1.0-2.0 wt.%C and decreased at carbon higher than 2.0 wt.%. The effective distribution of the coefficient of nickel in as-cast Fe-30 wt.% Ni-12.5 wt.% Co-xC Invar alloy increased with increasing carbon content. The volume fraction of they phase of Fe-30 wt.% Ni-12.5 wt.% Co-xC alloy increased with increasing carbon content. The microstructure of Fe-30 wt.% Ni-12.5 wt.% Co-xC alloy changed with the carbon content was independent of the coefficient of thermal expansion. The Curie temperature changed linearly with the carbon content and was similar to the change of the coefficient of thermal expansion. Moreover, the coefficient of thermal expansion decreased when the ratio of saturation magnetization to Curie temperature ($\sigma_s/T_c$) increased, decreasing the Curie temperature and showed a specific relationship with the magnetic properties of the Fe-30 wt.% Ni-12.5 wt.% Co-xCInvar alloy.