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961.
Hong?Kyung?PakEmail author Jeong?Hyeong?Park 《Annals of Global Analysis and Geometry》2006,30(1):97-105
The main purpose of the present paper is to study geometric properties of transversal (infinitesimal) harmonic transformations for Riemannian foliations. For the point foliation these notions are discussed in [14]. Especially we treat transversal infinitesimal harmonic transformations from the standpoint of λ-automorphisms. Our results extend those obtained in
[6, 7, 15] for the case of harmonic foliations.
Mathematics Subject Classifications (2000): Primary 53C20, Secondary 57R30. 相似文献
962.
Kyung Hoon Han 《Journal of Mathematical Analysis and Applications》2010,367(2):516-386
We establish a relationship between Schreiner's matrix regular operator space and Werner's (nonunital) operator system. For a matrix ordered operator space V with complete norm, we show that V is completely isomorphic and complete order isomorphic to a matrix regular operator space if and only if both V and its dual space V∗ are (nonunital) operator systems. 相似文献
963.
In the absence of a clear command and control structure, a key challenge in supply chain management is the coordination and alignment of supply chain members who pursue divergent and often conflicting goals. The newsvendor model is typically used as a framework to quantify the cost of misalignment and to assess the impact of various coordination initiatives. The application of the newsvendor framework, however, requires the specification of some probability distribution for the sources of uncertainty, and in particular, for the market demand. The specification of an adequate demand distribution becomes difficult in the absence of statistical data. We therefore consider a fuzzy approach to the newsvendor problem. We use several fuzzy parameters in the model for the demand, the wholesale price, and the market sales price. We solve the fuzzy newsvendor problem to study three coordination policies: quantity discounts, profit sharing, and buyback. For each coordination policy, the optimal order quantity of the retailer is computed. The possible profits of the members in the supply chain are calculated with minimum sharing of private information. We further extend the fuzzy newsvendor model to a setting with a single manufacturer and multiple retailers under the assumption of ample capacity for the manufacturer. Detailed numerical examples are also provided. 相似文献
964.
Erdene‐Ochir Ganbold Yunhee Lee Kangtaek Lee Prof. Ohyun Kwon Dr. Sang‐Woo Joo Prof. 《化学:亚洲杂志》2010,5(4):852-858
The interfacial behavior of self‐assembled thin films of benzoic acid (BA) and phenylphosphonic acid (PPOA) anchored on TiO2 surfaces was studied by using temperature‐dependent diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. On the basis of the disappearance of the OH band from the infrared spectra at room temperature, BA and PPOA appear to adsorb onto TiO2 surfaces through carboxylate and phosphonate groups, respectively. Above 420 °C, DRIFT spectra indicated that both BA and PPOA desorb from TiO2 surfaces; however, dissimilar desorption behavior could be inferred for BA and PPOA from their temperature‐dependent spectral changes. The benzene ring modes of PPOA remained above 420 °C, whereas those of BA disappeared. Density functional theory calculations showed that the adsorption of BA and PPOA on TiO2 surfaces corresponded to bidentate bridging geometry on TiO2 surfaces, and the adsorption of PPOA is stronger than that of BA. The monodentate structures with energy differences of 4.9 and 9.1 kcal mol?1 from the most stable bidentate structures of BA and PPOA, respectively, from the DFT calculations appeared to be possible, particularly at the high temperatures above 420 °C, as indicated by the intensified OH bands. The geometry of PPOA was also estimated to be more upright standing than that of BA on TiO2 surfaces, which may lead a rather straight detachment from the TiO2 surfaces based on the presence of in‐plane ring modes in the DRIFT spectra at the higher temperature. 相似文献
965.
Cheonik Joo Sunhae Kang Sun Min Kim Hogyu Han Jung Woon Yang 《Tetrahedron letters》2010,51(46):6006-6007
A highly efficient and eco-friendly oxidation of benzoins 1 to benzils 2 using sodium hydride has been developed. 相似文献
966.
Hye-Lim Lee TacGhee Yi Kyung Mi Woo Hyun-Mo Ryoo Gwan-Shik Kim Jeong-Hwa Baek 《Experimental & molecular medicine》2010,42(6):437-445
TNF-α, a proinflammatory cytokine, inhibits osteoblast differentiation under diverse inflammatory conditions; however, the underlying mechanisms in terms of the TNF-α signaling pathway remain unclear. In this study, we examined the role of Msx2 in TNF-α-mediated inhibition of alkaline phosphatase (ALP) expression and the signaling pathways involved. TNF-α down-regulated ALP expression induced by bone morphogenetic protein 2 (BMP2) in C2C12 and Runx2-/- calvarial cells. Over-expression of Msx2 suppressed BMP2-induced ALP expression. Furthermore, TNF-α induced Msx2 expression, and the knockdown of Msx2 by small interfering RNAs rescued ALP expression, which was inhibited by TNF-α. TNF-α activated the NF-κB and the JNK pathways. Inhibition of NF-κB or JNK activation reduced the inhibitory effect of TNF-α on ALP expression, whereas TNF-α-induced Msx2 expression was only suppressed by the inhibition of the NF-κB pathway. Taken together, these results indicate that Msx2 mediates the inhibitory action of TNF-α on BMP2-regulated osteoblast differentiation and that the TNF-α-activated NF-κB pathway is responsible for Msx2 induction. 相似文献
967.
Choi KM Lee SJ Choi JH Park TJ Park JW Shin WH Kang JK 《Chemical communications (Cambridge, England)》2010,46(45):8609-8611
A facile route to fabricate a protein-immobilized network pattern circuit for rapid and highly sensitive diagnosis was developed via the evaporation directed impromptu patterning method and selective avian influenza virus (AIV) immobilization. The response to the 10 fg mL(-1) anti-AI antibody demonstrates that this easy and simple circuit has about 1000 times higher sensitivity compared to those of conventional approaches. 相似文献
968.
969.
970.
In this article, the development of a novel technique to fabricate spherical polymeric microcapsules by utilizing microfluidic technology is presented. Atom transfer radical polymerization (ATRP) was employed to synthesize well-defined amphiphilic block copolymers. An organic polymer solution was constrained to adopt the spherical droplets in a continuous water phase at a T-junction microchannel, and the generation of the droplets was studied quantitatively. The flow conditions of two immiscible solutions were adjusted for the successful generation of the polymer droplets. The morphology of the microcapsules was examined. The efficiency of these polymer microcapsules as containers for the storage and controlled release of loaded molecules was evaluated by encapsulating the microcapsules with Congo-red dye and investigating the release performance using temperature controlled UV-VIS spectroscopy. 相似文献