• Title/Summary/Keyword: density index

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Constrained Dynamic Responses of Structures Subjected to Earthquake

  • Eun, Hee Chang;Lee, Min Su
    • Architectural research
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    • v.8 no.2
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    • pp.37-42
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    • 2006
  • Starting from the quadratic optimal control algorithm, this study obtains the relation of the performance index for constrained systems and Gauss's principle. And minimizing a function of the variation in kinetic energy at constrained and unconstrained states with respect to the velocity variation, the dynamic equation is derived and it is shown that the result compares with the generalized inverse method proposed by Udwadia and Kalaba. It is investigated that the responses of a 10-story building are constrained by the installation of a two-bar structure as an application to utilize the derived equations. The structural responses are affected by various factors like the length of each bar, damping, stiffness of the bar structure, and the junction positions of two structures. Under an assumption that the bars have the same mass density, this study determines the junction positions to minimize the total dynamic responses of the structure.

THE STUDY ABOUT THE DIAGNOSTIC PARAMETERS OF OPSTEOPOROSIS ON PANORAMIC RADIOGRAPH (골다공증의 파노라마방사선사진상 진단학적 매개변수에 관한 연구)

  • Lee, Yong Gyoo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.20 no.4
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    • pp.279-283
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    • 1998
  • The osteoporosis is a disease that represents a reduction in the volume of bony tissue relative to whole bone volume. And mandible also may be affected. Such porotic mandible may influence the result of the surgery like dental implant surgery relating mandible. So, the author examed the panoramic view of 89 persons for finding the possibility of useful diagnostic parameters of osteoporosis. To know the correlationship between the condition of vertebra and mandible, bone marrow density of lumbar spine from 2nd to 4th, and the number of residual tooth, panoramic mandibular index (PMI), angular cortical bone thickness (ACT) and ramus cortical bone thickness (RCT) were compared. The result is that PMI and ACT have similar relative weak linear correlationship, RCT have very weak linear correlationship, the number of residual tooth have not linear correlationship.

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Treatment of Organic Waste with Microorganisms of Mixed Population

  • Kim, Gi-Eun
    • KSBB Journal
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    • v.22 no.3
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    • pp.129-133
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    • 2007
  • This study represents that a removal efficiency of organic matters in wastewater is activated by a sludge process using new mixed microbial population. In case of mixed microorganisms, removal rates of suspended solid (SS), biochemical oxygen demand (BOD) and chemical oxygen demand (COD) were over 90 percent under experimental condition, and removal efficiency of organic matters, sludge density index (SDI) and capillary suction time (CST) in mixed population were higher than that in not-mixed microorganism, while total kjeldahl nitrogen (TKN) and total phosphorus (T-P) which indicate a degree of eutrophication were removed easily in both case. From these results, we may propose that an application of the mixed microbial population is useful to treat domestic wastewater including a great deal of organic matters.

The Study on Optical Properties by Adding $La_2O_3$ in Multicomponent Glass Fiber (다성분계 Glass Fiber의 $La_2O_3$ 첨가에 따른 광학적 특성에 관한 연구)

  • 김용호;강원호
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1994.11a
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    • pp.21-23
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    • 1994
  • By adding La₂O₃ to optical multicomponent glass composition, after making mother glass and core fiber that enable to enlarge the infrared transmittance region, then surveyed the optical properties. Through thermal analysis of the glass abstained by melt-quenching after selecting stable basic composition on devitrification and replace SiO₂ by 4-12wt% La₂O₃. As La₂O₃ increases up to l2wt% transition temperature, refractive index, density, deformation temperature increased, whereas thermal expansion coefficient decreased. As a result of inspectig transmittance in UV/VIS/IR region, visable region indicated the decrease of transmittance by increasing the La₂O₃ and transmittance region was enlarged by increasing the La₂O₃ in IR region. Also, fabricate core fiber at 820℃ and severy the optical loss we could fact that La₂O₃ composition added 12wt% showed the minimum optical loss.

Pure Culture Assay with Streptomyces viridosporus T7A for Biodegradability Determination of Oxidized Potato Starch/Polyethylene Films

  • Kim, Meera;Kim, Sung-Hong
    • Preventive Nutrition and Food Science
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    • v.6 no.2
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    • pp.112-116
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    • 2001
  • Oxidized potato starch/polyethylene (PE) cast films were prepared with different percentages of linear low density PE (LLDPE), oxidized potato starch and prooxidant. For the determination of biodegradability of the films, lignocellulose-degrading Streptomyces viridosporus T7A (ATCC 39115) was used. Films were chemically disinfected and incubated with S. viridosporus by shaking at 100 rpm at 37$^{\circ}C$ for eight weeks. Hydroxyl indices of the films by Fourier-Transform Infrared Spectroscopy, mechanical Properties of the films by Instron and film morphology by scanning electron microscope (SEM) were measured. The hydroxyl index of the film containing the oxidized potato starch incubated with S. viridosporus T7A was higher than that of the corresponding control. All the films containing 5% and 10% oxidized starch showed a decrease of tensile strength on the films after incubation when the corresponding uninoculated film was compared. In the oxidized starch/PE film incubated with S. viridosporus T7A, partial destruction of starch and PE was examined by SEM.

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Cutaneous asthenia associated with Ehlers-Danlos syndrome in a Yorkshire terrier

  • Cho, Sung-Jin;Kim, Okjin
    • Korean Journal of Veterinary Research
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    • v.47 no.1
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    • pp.91-94
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    • 2007
  • tisue disease of dog and cat, resembling Ehlers-Danlos syndrome (EDS) in man. EDS is characterizedby loose, hyperextensible and, fragile skin, it is attributed to mutations in connective tisue gene. Thesemutations cause defects in type I or II collagen synthesis and as a result lack of strength or elasticityto skin, joint, ligament and vessels. EDS-affected animals often experience subcutaneous hematomas thathave long bleeding times. The 4-years old male Yorkshire terrier was evaluated because of subcutaneoushematoma after stifle surgery. Clinical examination revealed a thin and hyperextensible skin and jointlaxity. The degree of skin extensibility index was 23.4%, marked skin stretchy. Clinical diagnosis wasconfirmed by histophathological examination of a skin biopsy revealing reduced packing density ofcollagen fiber of skin.

Geotechnical Properties of Soil-Bentonite Mixtures (흙-벤토나이트 혼합물의 지반공학적 특성)

  • 채교익;권무남
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.43 no.5
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    • pp.132-144
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    • 2001
  • Iln order to figure out criteria of bentonite for using as impervious material of waste landfill, laboratory experiments were performed to reveal the geotechnical properties of soil-bentonite mixtures such as compaction test, direct shear test, unconfined compression test, triaxial compression test, consolidation test and permeability test. The results of the study are summarized as follows ; 1. Based on the compaction test, optimum moisture content increased with the increase of bentonite content, but maximum dry density decreased. 2. In unconfined compression test, the maximum strength of the soil-bentonite mixtures appeared at 10% bentonite content. The correlation equation between stress($\sigma$) and strain($\varepsilon$) of the soil-bentonite mixtures is given by ; $\sigma=\frac{a\cdot\varepsilon}{\varepsilon^n+b}$ 3. In shear test of the mixtures. the shear strength showed an increasing trend with increase of bentonite content and the maximum shear strength appeared at 10% bentonite content. 4. In consolidation test, the coefficient of compressibility $(a_v)$$(m_v)$$(C_v)$

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System Identification of In-situ Vehicle Output Torque Measurement System (차량 출력 토크 측정 시스템의 시스템 식별)

  • Kim, Gi-Woo
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.2
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    • pp.85-89
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    • 2012
  • This paper presents a study on the system identification of the in-situ output shaft torque measurement system using a non-contacting magneto-elastic torque transducer installed in a vehicle drivline. The frequency response (transfer) function (FRF) analysis is conducted to interpret the dynamic interaction between the output shaft torque and road side excitation due to the road roughness. In order to identify the frequency response function of vehicle driveline system, two power spectral density (PSD) functions of two random signals: the road roughness profile synthesized from the road roughness index equation and the stationary noise torque extracted from the original torque signal, are first estimated. System identification results show that the output torque signal can be affected by the dynamic characteristics of vehicle driveline systems, as well as the road roughness.

Analysis of Susceptibility in Landslide Distribution Areas (산사태 발생지역에서의 민감성 분석에 관한 연구)

  • 양인태;유영걸;천기선;전우현
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2004.11a
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    • pp.381-384
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    • 2004
  • The goal of this study is to generate a landslide susceptibility map using GIS(geographic information system) based method. A simple and efficient algorithm is proposed to generate a landslide susceptibility map from DEM(digital elevation model) and existing maps. The categories of controlling factors for landslides, aspect of slope, soil, topographical index, landuse, vegetation are defined, because those factors are said to have relevance to landslide and are easy to obtain theirs sources. The weight value for landslide susceptibility is calculated from the density of the area of landslide blocks in each class. Finally, a map of susceptibility zones is produced using the weight value of all controlling factors, and then each susceptibility zone is evaluated by comparing with the distribution of each controlling factor class.

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Hypolipidemic and Antioxidative Properties of Tocotrienol-rich Fraction (TRF) Supplementation in High Fat-fed Rats

  • Choi, Young-Min;Lee, Jun-Soo
    • Food Science and Biotechnology
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    • v.18 no.6
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    • pp.1528-1531
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    • 2009
  • In this study, we investigated a dose-dependent hypolipidemic and antioxidant effects of tocotrienol-rich fraction (TRF) from grape seeds. After induction of hyperlipidemia for 4 weeks, rats were supplemented with different dose (5, 25, and 50 mg/kg BW/day) of TRF for 1 week. Oral administration of TRF (50 mg/kg BW/day) decreased the plasma triglyceride (TG, 162.6 mg/dL), total cholesterol (TC, 83.7 mg/dL), low density lipoprotein-cholesterol (LDL-C, 20.3 mg/dL), malondialdehyde contents (MDA, 3.3 nmol/dL), and atherogenic index (AI, 2.0) compare to high-fat diet group. These data suggest that TRF supplementation has significant health benefits through the modulation of physiological functions that include various atherogenic lipid profiles and antioxidative status in hyperlipidemia.