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121.
This work investigates different hemp surface modifications (mercerization, maleated polyethylene (MAPE) addition in solution or in melt blending) to improve the properties of linear medium density polyethylene (LMDPE). From the composites produced, a complete morphological and tensile characterization was performed for a fixed hemp content (30% wt.). The morphological analysis showed that both the direct (melt blending) and solution modifications were able to significantly improve the composites interface quality and therefore the tensile properties (151% increase in modulus and 36% increase in strength over the neat matrix) within the range of conditions tested. 相似文献
122.
In this paper we study a system of linear operators between finite-dimensional Euclidean spaces. Emphasis is made on unbounded systems and sufficient conditions are established for their equi-surjectivity. An application is presented in which a system of approximate Jacobian matrices is used to obtain a parametric interior mapping theorem. A multiplier rule for vector problems is also derived. 相似文献
123.
Luc Tartar 《Archive for Rational Mechanics and Analysis》1990,111(2):121-133
Dedicated to
Bernard D. Coleman
on his sixtieth birthday 相似文献
124.
Maria del Carmen Yebra Lucía Rodríguez Luis Puig Amada Moreno-Cid 《Mikrochimica acta》2002,140(3-4):219-225
125.
Dinh Luc 《Mathematische Nachrichten》1986,129(1):149-155
Three theorems of the alternative for abstract linear inequality systems which depend on random parameter are produced in infinite dimensions. 相似文献
126.
Liliane Bokobza Mostafa Rahmani Colette Belin Jean‐Luc Bruneel Nour‐Eddine El Bounia 《Journal of Polymer Science.Polymer Physics》2008,46(18):1939-1951
The reinforcement of a styrene‐butadiene rubber (SBR) by single fillers—carbon black (CB) or multiwall carbon nanotubes (MWNTs)—or by mixtures of CB and MWNTs, is investigated. The morphologies, mechanical and electrical properties of the composites, are analyzed. A significant improvement in the tensile properties is observed for samples containing a dual phase. Using atomic force (AFM) and transmission electron (TEM) microscopies, we demonstrate that the double loading improves the dispersion of the nanotubes in SBR. Electrical measurements show lower resistivity and a lower percolation threshhold for composites containing blends of fillers, which provides further evidence of better dispersion. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 46: 1939–1951, 2008 相似文献
127.
128.
We discuss a case study of an industrial production-marketing coordination problem involving component commonality. For the product line considered, the strategic goal of the company is to move from the current low volume market to a high volume market. The marketing department believes that this can be achieved by substantially lowering the end products’ prices. However, this requires a product redesign to lower production costs in order to maintain profit margins. The redesign decision involves grouping end products into families. All products within one family use the same version of some components. This paper fits in the stream of recent literature on component commonality where the focus has shifted from inventory cost savings to production and development cost savings. Further, we consider both costs and revenues, leading to a profit maximization approach. The price elasticity of demand determines the relationship between the price level and number of units sold. Consequently, we integrate information from different functional areas such as production, marketing and accounting. We formulate the problem as a net-present-value investment decision. We propose a mixed integer nonlinear optimization model to find the optimal commonality decision. The recommendation based on our analysis has been implemented in the company. In addition, the application allows us to experimentally validate some claims made in the literature and obtain managerial insights into the trade-offs. 相似文献
129.
Luc Lambs Frédéric Brunet Jean‐Luc Probst 《Rapid communications in mass spectrometry : RCM》2009,23(16):2543-2550
The Garonne is the largest river in the south‐west of France, and its drainage basin stretches between the Pyrénées and the Massif Central mountains. Until now, no water stable isotope study has been performed on the whole Garonne river basin which is composed of different geological substrata, and where the water resources are limited during the dry summer period. This study focuses on the Garonne river and its tributaries from the Pyrénées foothill upstream to its confluence with the Lot River downstream. The aim of the study is to determine the origins of the surface waters using their chemical and stable isotopic compositions (18O, D and 13C), to better understand their circulation within the drainage basin and to assess the anthropogenic influences. The Garonne displays a specific 18O seasonal effect, and keeps its Pyrénean characteristics until its confluence with the Tarn River. The difference in the dissolved inorganic carbon (DIC) comes mainly from the change in lithology between the Pyrénées and the Massif Central mountains. Agriculture activity is only detected in the small tributaries. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
130.
Scalarization of vector optimization problems 总被引:5,自引:0,他引:5
D. T. Luc 《Journal of Optimization Theory and Applications》1987,55(1):85-102
In this paper, we investigate the scalar representation of vector optimization problems in close connection with monotonic functions. We show that it is possible to construct linear, convex, and quasiconvex representations for linear, convex, and quasiconvex vector problems, respectively. Moreover, for finding all the optimal solutions of a vector problem, it suffices to solve certain scalar representations only. The question of the continuous dependence of the solution set upon the initial vector problems and monotonic functions is also discussed.The author is grateful to the two referees for many valuable comments and suggestions which led to major imporvements of the paper. 相似文献