• Title/Summary/Keyword: Bore

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Numerical Analysis on Wave Characteristics around Submerged Breakwater in Wave and Current Coexisting Field by OLAFOAM (파-흐름 공존장내 잠제 주변에서 OLAFOAM에 의한 파랑특성의 수치해석)

  • Lee, Kwang-Ho;Bae, Ju-Hyun;An, Sung-Wook;Kim, Do-Sam;Bae, Kee Seung
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.28 no.6
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    • pp.332-349
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    • 2016
  • OLAFOAM is the powerful CFD code and is an expanded version of $OpenFOAM^{(R)}$, for wave mechanics simulation. The $OpenFOAM^{(R)}$ does provide many solvers to correspond to each object of the numerical calculation in a variety of fields. OLAFOAM's governing equation bases on VARANS (Volume-Averaged Reynolds-Averaged Navier-Stokes) equation, and the finite volume method is applied to numerical techniques. The program is coded in C++ and run on the Linux operating system. First of all, in this study, OLAFOAM was validated for 1) wave transformation inside porous structure under bore and regular wave conditions, 2) wave transformation by submerged breakwater under regular wave condition, and 3) regular wave transformation and resultant vertical velocity distribution under current by comparison with existing laboratory measurements. Hereafter, this study, which is almost no examination carried out until now, analyzed closely variation characteristics of water surface level, wave height, frequency spectrum, breaking waves, averaged velocity and turbulent kinetic energy around porous submerged breakwater in the wave and current coexisting field for the case of permeable or impermeable rear beach. It was revealed that the wave height fluctuation according to current direction(following or opposing) was closely related to the turbulent kinetic energy, and others.

Physicochemical Properties of Oxidized Waxy Maize Starches with Sodium Hypochlorite (찰옥수수 산화전분의 이화학적 특성)

  • Chung, Man-Gon;Jeon, Young-Seung;Lee, Sur-Koo;Park, Jong-Moon;Lim, Bun-Sam
    • Korean Journal of Food Science and Technology
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    • v.30 no.1
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    • pp.42-48
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    • 1998
  • Physicochemical properties of waxy maize starch and oxidized waxy maize starch with sodium hypochlorite $(0{\sim}60\;mg\;CL_2/g\;starch,40^{\circ}C,\;pH\;10,\;3.0\;hr)$ were studied. As sodium hypochlorite concentration was increased, the content of crude lipid and crude protein of the oxidized starch were decreased. And crude protein content and whiteness was considered to show negative regression. However, the crude ash content of the oxidized starch increased significantly with oxidation and bore a positive regression to the chlorine content. There was a progressive increase in the carboxyl content with increasing oxidant level. After pasting in hot water and cooling, viscosity of the oxidized starches were drastically lower than that of native starch . As carboxyl contents of the oxidized starch increased, the solubility and swelling power was increased. When waxy maize starch treated with 0, 1.5, 3.0 and 6.0% sodium hypochlorite, temperature of initial gelatinization of oxidized starch was shown to 65, 65, 60 and $50^{\circ}C$, respectively. The oxidized waxy maize starches also form clearer pastes. Water binding capacity of the oxidized starch decreased as the degree of carboxyl group substitution increased. Waxy maize starch has polygonal and some round granules which range from about 3.7 to $20\;{\mu}m$ in diameter. Surface appearance of the waxy maize starch became rough when oxidized with sodium hypochlorite. When homogenate of the oxidized waxy maize starch solution and corn germ oil was stored under room temperature for 24 hours, the emulsion stability was considered to depend on starch concentration and degree of substitution.

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Pole-pole array electrical resistivity survey and an effective interpretational scheme of its data (2극법 전기비저항 탐사 자료의 효율적인 해석방법)

  • Cho Dong-Heng;Lee Chang Yourl;Jee Sang-Keun
    • 한국지구물리탐사학회:학술대회논문집
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    • 2000.09a
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    • pp.112-131
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    • 2000
  • In spite of its many strong points, pole-pole electrode configuration is not often used for ground electrical resistivity survey except for bore hole survey as normal logging and for archaeological investigation. Above all, poor spatial resolution of pole-pole survey may be responsible for this. But recent experiences so far gained by the present authers lead them to think that pole-pole survey can be at least a viable means of reconnaissance survey in near-surface conductive environment and an effective interpretational scheme may augment its resolution. As well known, a response of any other electrode configuration is a linear combination of pole-pole responses. Based on this principle of linear superposition and the principle of reciprocity, the other 'responses' can be derived with simple additions and subtractions of pole-pole responses. Though such responses are not always correct due to the adverse effects of noises, combined with the potential decay curves, they can be helpful to interprete better pole-pole survey data especially in connection of the resolution. This can be comparable to the use of the first or second derivatives of gravity and magnetic intensity surveys.

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In Vitro and In Vivo Studies of Different Liposomes Containing Topotecan

  • Hao, Yan-Li;Deng, Ying-Jie;Chen, Yan;Wang, Xiu-Min;Zhong, Hai-Jun;Suo, Xu-Bin
    • Archives of Pharmacal Research
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    • v.28 no.5
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    • pp.626-635
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    • 2005
  • Liposome as a carrier of topotecan (TPT), a promising anticancer drug, has been reported in attempt to improve the stability and antitumor activity of TPT. However, the biodistr ibution pattern of TPT liposome in vivo and PEG-modified liposome containing TPT have not been studied systemically. In this paper, the in vitro stability and in vivo biodistribution behavior of several liposomes containing TPT with different lipid compositions and PEG-modification were studied. Compared with the 'fluid' liposome (S-Lip) composed of soybean phosphatidylcholine (SPC), the 'solid' liposome (H-Lip) composed of hydrogenated soybean phosphatidylcholine HSPC decreased the leaking efficiency of TPT from liposome and enhanced the stability of liposome in fetal bovine serum (FBS) or human blood plasma (HBP). The results of biodistribution studies in S$_{180}$ tumor-bearing mice showed that liposomal encapsulation increased the concentrations of total TPT and the ratio of lactone form in plasma. Compared with free TPT, S-Lip and H-Lip resulted in 5- and 19- fold increase in the area under the curve (AUC$_{0\rightarrow\propto}$), respectively. PEG- modified H-Lip (H-PEG) showed 3.7-fold increase in AUC$_{0\rightarrow\propto}$ compared with H-Lip, but there was no significant increase in t$_{1/2}$ and AUC$_{0\rightarrow\propto}$ for PEG-modified S-Lip (S-PEG) compared with S-Lip. Moreover, the liposomal encapsulation changed the biodistribution behavior, and H-Lip and H-PEG dramatically increased the accumulation of TPT in tumor, and the relative tumor uptake ratios were 3.4 and 4.3 compared with free drug, respectively. There was also a marked increase in the distribution of TPT in lung when the drug was encapsulated into H-Lip and H-PEG. Moreover, H-PEG decreased the accumulation of TPT in bore marrow compared with unmodified H-Lip. All these results indicated that the membrane fluidity of liposome has an important effect on in vitro stability and in vivo biodistribution pattern of liposomes containing TPT, and PEG-modified 'solid' liposome may be an efficient carrier of TPT.

Effects of Indomethacin on the physiologic root resorption of deciduous teeth in dogs (인도메타신이 개의 유치 치근 흡수에 미치는 영향)

  • Shin, Kang-Seob;Kang, Yoon-Goo;Lee, Ki-Soo
    • The korean journal of orthodontics
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    • v.35 no.2 s.109
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    • pp.106-115
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    • 2005
  • This study was aimed to investigate the effects of indomethancin on physiologic root resorption and to examine the dental pulp and tissue changes around the resorbing teeth 13-14 week old six mongrel dogs were divided into 3 groups, two experimental groups administered indomethacin 2mg/kg/day and 8mg/kg/day orally two times a day for 14 days respectively. and control group administered a placebo The deciduous incisors showing root resorption were selected. fixed for 24 hrs in $10\%$ formalin solution. demineralized in $10\%$ EDTA solution. Invested in paraffin and sectioned in $5{\mu}m$ thick sections. The preparations were stained with H&E staining and Masson's trichrome staining and examined under the light microscope Observation revealed that deciduous root resorbing tissue resembles inflammatory tissue and accompanies bore remodelling. The dental pulp was formal except the area near root resorption. well organized columnar odontoblasts layer under the predentin, anud the odontoblasts near root resorption were cuboidal or flat cells in the disrupted layer under the predentin. Indomethacin administered group showed a partial decrease in the number of odontoclasts and nucleus But there was no sign of pulp change by indomethacin. These results suggest that indomethacin inhibits recruitment of odontoclasts partially and that of osteoclasts more. and so when it is administered for long periods deciduous root resorption can be delayed and eruption of the successor can be delayed for a short period.

Decay Resistance and Effectiveness of CCA Preservative against Decay on the 4 Imported Softwoods (수입침엽수(輸入針葉樹) 4수종(樹種)의 내후성(耐朽性) 및 CCA계(系) 목재방부제(木材防腐劑) 처리(處理)에 따른 방부효과(防腐效果))

  • Lee, Jong Shin;Kim, Young Sik;Han, Kie Sun
    • Korean Journal of Agricultural Science
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    • v.22 no.1
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    • pp.42-48
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    • 1995
  • With the aim to investigation of decay resistance and optimum concentration in chrome-copper-arsenic(CCA) preservative treatment on the imported softwoods from Siberia and North america, preservative absorption after CCA impregnation, weight losses and degradation patterns by decay fungi were examined. The density and latewood rate of Siberia softwoods(Spruce and Larch) were higher than those of North america softwoods(Douglas-fir and Western hemlock), resulting in the decrease of the CCA preservative absorption in the Siberia softwoods. In the case of untreated softwoods, decay resistance against Coriolus versicolor was lower than against Tyromyces palustris. For CCA treated softwoods, preservative effectiveness increased with increase in concentration of CCA solution. When treated with 0.7% CCA solution, efficiency value was more than 80 and 90 for C. versicolor and T. palustris, respectively. From this results, in the CCA preservative treatment for imported softwoods, it can be concluded that optimum concentration of CCA solution is approximately 0.7%. The absorption of CCA preservative distributed in the range of 3.8 and $5.5kg/m^3$. After exposure to testing fungi, in the untreated softwoods, bore holes formed in the cell walls and bordered pits, moreover, bordered pit canals enlarged by the fungi. However, 0.5% CCA treated softwoods was almost no deterioration in the cell walls and bordered pits due to decay.

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Determining the Orientations of Broadband Stations in South Korea using Ambient Noise Cross-correlation (배경잡음 교차상관을 이용한 국내 광대역 지진계의 방위각 보정값 측정)

  • Lee, Sang-Jun;Rhie, Junkee
    • Geophysics and Geophysical Exploration
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    • v.18 no.2
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    • pp.85-90
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    • 2015
  • Orientation corrections for Korean seismic stations were calculated by using ambient noise cross-correlation. This method uses Rayleigh waves extracted from ambient noise cross-correlation instead of teleseismic waveforms from earthquakes, which have been generally used for previous studies. The theoretical background of the method is that the phase of radial-vertical cross-correlation function should be the same as that of $90^{\circ}$ phase-shifted vertical-vertical cross-correlation function. The results calculated from stacked cross-correlograms from Jan. 2007 to Sep. 2008 are comparable to the previous results obtained from teleseismic waveforms. In addition, overall the standard deviations of orientation corrections are less than $5^{\circ}$. The temporal variation in orientation corrections calculated for every 30 days shows no significant change and also standard deviations of them are mostly less than $5^{\circ}$. This means that the orientations of stations used in this study have been kept constant during the period. The sensitivity test for stacking period of the ambient noise cross-correlation method shows that continuous ambient noise record of at least about 30 days is required for estimating reliable orientation corrections.

Quality of Building Stones by Physical Properties (물성에 의한 석재의 품질도)

  • 박덕원
    • The Journal of Engineering Geology
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    • v.14 no.1
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    • pp.61-69
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    • 2004
  • Building stones are used mainly as a material for making decoration and sculpture, and consequently they must have predominant physical properties extensively. Among various physical properties, the coefficient of pore dominates the usefulness of building stones, so the plans were made for establishing the quality classification of building stones with respect to the nature of pore. For this study, bore-hole core samples according to the depth of the biotite granites and the granitic gneiss were applicated. From the related chart between porosity and absorption ratio, Mungyeong granitic gneiss($Gn_1$) shows the widest phase of distribution in the range of measurement values, and the values decrease in the order of Pocheon granite($Gr_2$) and Mungyeong granite($Gr_1$) in the range. The strength of each rock mass varies with the degree of alteration. Also in correlation between compressive strength and tensile strength, the range of measurement values decrease in the order of $Gn_1$, $Gr_2$and $Gr_1$. Porosity is adopted as a representative physical property for establishing the quality classification of building stones, and then relative evaluation was made with regard to various physical properties. From the related chart between porosity(n)-specific gravity(G), absorption ratio(Ab), compressive strength(${\sigma}_{c}$), tensile strength(${\sigma}_{t}$), shore hardness(Hs) and Young's modulus($E_{t}$), standard of each grade is established.

A Comparative Study on Power Tool Manufacturers' Products Spec. and Design Development Features - By the Case Study on BOSCH, BLACK&DECKER and KEYANG Electrics- (전동공구 회사의 제품사양별 디자인개발특성 비교연구 -보슈(BOSCH), 블랙앤데커(BLACK&DECKER), 계양전기 사례를 중심으로 -)

  • 채승진
    • Archives of design research
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    • v.17 no.1
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    • pp.383-392
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    • 2004
  • The power tools is the product using working power generated by electric motor. Many companies are manufacturing numerous devices. Main features of tools are included various assembled products, small, light and solid and durable enough to match several standards. Fundamental requirements for the product is excellent performance and convenience for use. The quality of them depends on the equipped motor'(s) capability, accuracy of gear and endurance against worn-out. By adapting the state-of-the-art parts, they could be used in the place from home to heavy industry broadly. They can be classified electronic drills, grinders, saws and sanders families for the household appliances. For industrial tools, bore drill, grinder, polisher, and driver drill are classified as special and high priced group. This study presents the strategy of power tool development of BOSCH, BLACK&DECKER and KEYANG. Their products were analyzed in terms of product line and product mix concept. Then they are examined by design elements, such as color, shape and material for housing. As an analysis method, the image scale parameter and criteria were applied to each company's product.

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A Study on Influence of Antecedents and Activities within SCM on Balanced Scorecard Performance (SCM의 선행요인과 활동이 균형성과에 미치는 영향에 관한 연구)

  • Kim, Jong-Ryeol;Yang, Hae-Sool
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.5
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    • pp.1227-1242
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    • 2007
  • This study aims at grasping the influence of antecedents within SCM to information sharing and cooperation as well as the influence of information sharing on cooperation among the small & medium-sized manufacturing industries, thus ultimately opening the way to the study on the influence of major activities such as information sharing and cooperation within SCM on the business performance by classifying such influence into low perspectives of BSC. The results of this study revealed that the antecedents such as commitment and cultural similarities exercised a significant influence on information sharing while mutual trust and the size of a corporate weighing with cooperative activities. It also identified the fact that information sharing bore a significant influence on cooperation in terms of relationships among activities. For the relationships between the SCM activities and performance, cooperation proved significant to all four balanced scorecard performances with little significant influence of information sharing on balanced scorecard performance. However, taking into consideration of the significance of information sharing on cooperation as well as the significant influence of cooperation on balanced scorecard performance, it fumed out that information sharing also effected a indirect influence on such four types of balanced scorecard performance. In this regard, based on the results of this study, it was identified that information sharing and cooperation, major activities within SCM, had either direct or indirect influence, through the influence of antecedents, on the business balanced scoreboard performance measured from a customer perspective, a business process perspective, an innovation and teaming perspective and a financial perspective.

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