• Title/Summary/Keyword: combined shells

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Numerical Method for Nonlinear Analysis of Composite Shells under Constant Lateral Pressure and Incremented In-plane Compression (일정 횡압력과 증분 압축하중을 동시에 받는 복합재 쉘의 비선형 해석을 위한 수치기법 연구)

  • 김진호;권진희
    • Composites Research
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    • v.13 no.1
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    • pp.69-77
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    • 2000
  • This paper presents a modified arc-length method for the nonlinear finite element analysis of a structure which is loaded in incremental and fixed forces, simultaneously. The main idea of the method is to separate the displacement term by the constant force from that by the incremental force. Presented method is applied to the nonlinear analysis of isotropic shell structures separately loaded by lateral pressure or compression, and shows the excellent agreement with previous results. As an illustrative example of the applicability of the present algorithm, a parametric study is performed on the nonlinear buckling analysis of composite cylindrical panels under the combined load of the incremented compression and the constant lateral pressure.

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Design for Children's Han Bok Product with Variegated Natural Dyeing, Using Mixture Extract of Chrysanthemum indicum Linne and Onion Shell (감국과 양파껍질 추출물을 이용한 홀치기 천연염색 아동 패션한복 디자인)

  • Jang, Hyun-Joo
    • Fashion & Textile Research Journal
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    • v.22 no.5
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    • pp.561-569
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    • 2020
  • In this study, the dyeing of Chrysanthemum indicum Linne alone and the combined dyeing of Chrysanthemum indicum Linne and onion shell were first performed to compare dyeing properties. A combination extract of Chrysanthemum indicum Linne and onion shell can be expected to improve coloration. A Hanbok design for children used a natural dyeing fashion dyeing method to make the Chrysanthemum pattern. Chrysanthemum indicum Linne is a type of wild chrysanthemum with various medicinal effects for headache and stress relief, skin diseases, insomnia and depression. Widely used onion shells have medicinal properties that help prevent and treat various adult diseases. The colors of silk dyed exclusively by Chrysanthemum indicum Linne, and the colors of silk dyed by Chrysanthemum indicum Linne and onion shell extract are yellow; in addition, silk dyed by Chrysanthemum indicum Linne and onion shell extracts were almost all unchanged. Four hanboks, which are comfortable for children to wear and use, were produced using Chrysanthemum indicum Linne and onion shell extracts. If children wear hanbok fashion products with auspicious patterns, they can provide a chance to simultaneously experience the traditional symbolism of Korean patterns and culture. In addition, it is expected to develop pride in traditional dress culture.

INTERSTELLAR ENVIRONMENTS IN THE LARGEMAGELLANIC CLOUD

  • KIM SUNGEUN
    • Journal of The Korean Astronomical Society
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    • v.37 no.4
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    • pp.211-216
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    • 2004
  • We present the results of an H I aperture synthesis mosaic of the Large Magellanic Cloud (LMC), made by combining data from 1344 separate pointing centers using the Australia Telescope Compact' Array (ATCA) and the Parkes multibeam receiver. The resolution of the mosaiced images is 50" (<15 pc, using a distance to the LMC of 55kpc). This mosaic, with a spatial resolution .15 times higher than that which had been previously obtained, emphasises the turbulent and fractal structure of the ISM on the small scale, resulting from the dynamical feedback of the star formation processes with the ISM. We also have done a widefield panoramic survey of H$\alpha$ emission from the Magellanic Clouds with an imager mounted on the 16-inch telescope at Siding Spring Observatory. This survey produced H$\alpha$ images which are equal to the ATCA survey in area coverage and resolution. This survey allows us to produce a continuum-subtracted image of the entire LMC. In contrast with its appearance in the H$\alpha$ image, the LMC is remarkably symmetric in H I on the largest scales, with the bulk of the H I residing in a disk of diameter 8. $^{\circ}4$ (7.3 kpc) and a spiral structure is clearly seen. The structure of the neutral atomic ISM in the LMC is dominated by H I filaments combined with numerous shells and holes.

Use of Coulomb-Yukawa Like Correlated Interaction Potentials of Integer and Noninteger Indices and One-range Addition Theorems for Ψα-ETO in Evaluation of Potential of Electric Field Produced by Molecule

  • Guseinov, I.I.
    • Bulletin of the Korean Chemical Society
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    • v.30 no.11
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    • pp.2617-2620
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    • 2009
  • Using Coulomb-Yukawa like correlated interaction potentials of integer and noninteger indices the series expansion formulae in terms of multicenter overlap integrals of three complete orthonormal sets of ${\psi}^{\alpha}$‒exponential type orbitals and linear combination coefficients of molecular orbitals are established for the potential of electrostatic field produced by the charges of molecule, where $\alpha$ = 1, 0, ‒1, ‒2,${\cdots}$. The formulae obtained can be useful for the study of interaction between atomic--molecular systems containing any number of closed and open shells when the ${\psi}^{\alpha}$‒exponential type basis functions and Coulomb-Yukawa like correlated interaction potentials are used in the Hartree-Fock-Roothaan and explicitly correlated approximations. The final results are valid for the arbitrary values of parameters of correlated interaction potentials and orbitals. As an example of application, the calculations have been performed for the potential energy of interaction between electron and molecule $H_2O$ using combined Hartree-Fock-Roothaan equations suggested by the author.

Properties of Calcium Lactate Prepared from Calcined Littleneck Clam Ruditapes philippinarum Shell Powder (바지락(Ruditapes philippinarum) 패각 소성분말로 제조한 젖산칼슘의 특성)

  • Lee, Gyoon-Woo;Yoon, In Seong;Lee, Hyun Ji;Lee, Jung Suck;Kim, Jin-Soo;Heu, Min Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.49 no.4
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    • pp.436-444
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    • 2016
  • Clamshells, which comprise more than 50% of a clam’s weight, are a major byproduct of the clam industry and are mainly composed of insoluble calcium carbonate. This study investigates the use of clamshells as a natural calcium resource. Highly soluble powdered calcium lactate (LCCL) was prepared from the calcined powdered shells of littleneck clams (LCCP) using response surface methodology (RSM) to predict optimum conditions. These conditions, as derived from pH, solubility, and yield of 11 LCCLs manufactured according to the RSM model, were 1.80 M lactic acid and 1.13 M LCCP. The actual values of pH (6.98), solubility (93.99%), and yield (351.23%) under the optimized conditions were as predicted. The derived LCCL exhibited a strong buffering capacity in the range of pH 2.78-3.90 when combined with less than 2 mL of 1 N HCl. The ranges of calcium content and solubility of LCCL were 7.7-17.5 g/100 g and 96.6-98.9%, respectively. Fourier transform infrared spectroscopy (FT-IR) of the LCCL identified it as calcium lactate pentahydrate, and field emission scanning electron microscopy (FESEM) revealed an irregular and rod-like microstructure. These results confirm the potential use of clamshells, converted to highly soluble organic acid calcium, as an additive to enhance calcium content in food ingredients.

Study on the Wastewater treatment as a Coagulant Using the Waste Oyster Shells and Loess (폐굴껍질과 황토로 제조한 응집제를 利用한 폐수처리에 관한 연구)

  • 고현웅;장성호;성낙창
    • Resources Recycling
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    • v.11 no.2
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    • pp.45-51
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    • 2002
  • This study was performed to investigate removal efficiency of wastewater by the prepared coagulant using waste oyster shell and loess. Waste oyster shell and loess contain respectively high CaO(55.43% by weight), $SiO_2$(45.30% by weight). Waste oyster shell was calcined to improve the purity of CaO at the calcination condition of $900^{\circ}C$ for 2hours, and then crushed 0.074 mm(200mesh) size by ball mill. Also, coagulant was prepared with calcined waste oyster shell and loess powder by hydration reaction. Calcined waste oyster shell and loess powder were combined with mixing ratio of 6 : 4, 7:3, 8:2 and 9:1. Though comparison experiment between prepared coagulant and chemical )$Ca(OH_2$, prepared coagulant was proved as having replaceable possibility of chemical )$Ca(OH_2$in wastewater treatment plant.

Anaerobic Bacterial Degradation for the Effective Utilization of Biomass

  • Ohmiya, Kunio;Sakka, Kazuo;Kimura, Tetsuya
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.6
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    • pp.482-493
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    • 2005
  • Biomass is originally photosynthesized from inorgainic compounds such as $CO_2$, minerals, water and solar energy. Recent studies have shown that anaerobic bacteria have the ability to convert recalcitrant biomass such as cellullosic or chitinoic materials to useful compounds. The biomass containing agricultural waste, unutilized wood and other garbage is expected to utilize as feed, food and fuel by microbial degradation and other metabolic functions. In this study we isolated several anaerobic, cellulolytic and chitinolytic bacteria from rumen fluid, compost and soil to study their related enzymes and genes. The anaerobic and cellulolytic bacteria, Clostridium thermocellum, Clostridium stercorarium, and Clostridium josui, were isolated from compost and the chitinolytic Clostridium paraputrificum from beach soil and Ruminococcus albus was isolated from cow rumen. After isolation, novel cellulase and xylanase genes from these anaerobes were cloned and expressed in Escherichia coli. The properties of the cloned enzymes showed that some of them were the components of the enzyme (cellulase) complex, i.e., cellulosome, which is known to form complexes by binding cohesin domains on the cellulase integrating protein (Cip: or core protein) and dockerin domains on the enzymes. Several dockerin and cohesin polypeptides were independently produced by E. coli and their binding properties were specified with BIAcore by measuring surface plasmon resonance. Three pairs of cohesin-dockerin with differing binding specificities were selected. Two of their genes encoding their respective cohesin polypeptides were combined to one gene and expressed in E. coli as a chimeric core protein, on which two dockerin-dehydrogenase chimeras, the dockerin-formaldehyde dehydrogenase and the dockerin-NADH dehydrogenase are planning to bind for catalyzing $CO_2$ reduction to formic acid by feeding NADH. This reaction may represent a novel strategy for the reduction of the green house gases. Enzymes from the anaerobes were also expressed in tobacco and rice plants. The activity of a xylanase from C. stercorarium was detected in leaves, stems, and rice grain under the control of CaMV35S promoter. The digestibility of transgenic rice leaves in goat rumen was slightly accelerated. C. paraputrificum was found to solubilize shrimp shells and chitin to generate hydrogen gas. Hydrogen productivity (1.7 mol $H_2/mol$ glucos) of the organism was improved up to 1.8 times by additional expression of the own hydrogenase gene in C. paraputrficum using a modified vector of Clostridiu, perfringens. The hydrygen producing microflora from soil, garbage and dried pelletted garbage, known as refuse derived fuel(RDF), were also found to be effective in converting biomass waste to hydrogen gas.