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1.
Patrizia Tiberi-Vipraio 《Industry and innovation》1996,3(2):103-104
This paper reviews the scholarship concerning the rise to economic prominence of the Italian industrial districts, and the causes of some of the difficulties in which some districts have found themselves since the mid-1980s. The paper develops the main lines of the economic advantages that districts enjoyed during a period of rapid growth, resulting from the operation of a market in common which blends competition and cooperation. The effects of globalisation are changing this somewhat ‘idyllic’ picture, as the structure of linkages between firms comes under pressure. Prospects for the Italian districts in these new circumstances are discussed. 相似文献
2.
Patrizia Tiberi Vipraio 《Industry and innovation》1996,3(2):135-152
3.
Damiana Chinese Antonella Meneghetti Gioacchino Nardin Patrizia Simeoni 《国际能源研究杂志》2007,31(9):829-848
A mixed integer linear programming model combined with a more traditional design by scenarios is proposed to optimize facilities size and operation mode of a municipal energy system involving significant civil centres and a hospital. Moving from the need of a new heat and power station for the local hospital due to the construction of new pavilions, the opportunity of involving other centres in the neighbourhood in a distributed cogeneration system is analysed, increasing system complexity step by step. Smaller cogeneration units tailored to hospital needs are rewarding ventures with relatively low risks but, in a country whose traditional power generation systems heavily rely on fossil fuels and where energy policy and market conditions can make it profitable to sell surplus power, district heating systems foster the installation of larger cogenerators and lead thereby to higher profits and to better performance as for primary energy savings and greenhouse gases emission reduction. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
4.
Claudio Arbib Fabrizio Marinelli 《International Journal of Flexible Manufacturing Systems》2003,15(4):333-354
A cook has to prepare n cakes using an oven with two racks. According to the recipe, the i-th cake has to be baked for exactly a
i minutes. Cakes to be cooked are taken from a table and carried to the oven, and once cooked are carried back to the table by means of a trolley that can carry two cakes at a time. What is the minimum number q
* of round trips required of the cook? This problem has application to the operation scheduling of transportation systems and to material cutting. A different problem arises according to whether the cook accepts or not to stay near the oven for awhile with the trolley. If the trolley cannot be idle at the oven, an optimum schedule with no oven idle-time always exists: consequently, the trolley schedule is trivial, and the problem is transformed into a set packing. For this case, we propose and test a heuristic method which generates all of the promising columns of the set packing, and solves the resulting problem by branch-and-bound. Instead, if the trolley can be idle at the oven for a limited amount of time, a problem arises to find an optimal schedule of the trolley: in this case we show how to use a scaling technique in order to obtain a very good feasible solution by the method above. 相似文献
5.
6.
Patrizia Marchese Maria Lombardi Maria Elena Mantione Domenico Baccellieri David Ferrara Roberto Chiesa Ottavio Alfieri Chiara Foglieni 《International journal of molecular sciences》2021,22(8)
Atherothrombosis exposes vascular components to blood. Currently, new antithrombotic therapies are emerging. Herein we investigated thrombogenesis of human arteries with/without atherosclerosis, and the interaction of coagulation and vascular components, we and explored the anti-thrombogenic efficacy of blockade of the P2X purinoceptor 7 (P2X7). A confocal blood flow videomicroscopy system was performed on cryosections of internal mammary artery (IMA) or carotid plaque (CPL) determining/localizing platelets and fibrin. Blood from healthy donors elicited thrombi over arterial layers. Confocal microscopy associated thrombus with tissue presence of collagen type I, laminin, fibrin(ogen) and tissue factor (TF). The addition of antibodies blocking TF (aTF) or factor XI (aFXI) to blood significantly reduced fibrin deposition, variable platelet aggregation and aTF + aFXI almost abolished thrombus formation, showing synergy between coagulation pathways. A scarce effect of aTF over sub-endothelial regions, more abundant in tissue TF and bundles of laminin and collagen type I than deep intima, may suggest tissue thrombogenicity as molecular structure-related. Consistently with TF-related vascular function and expression of P2X7, the sections from CPL but not IMA tissue cultures pre-treated with the P2X7 antagonist A740003 demonstrated poor thrombogenesis in flow experiments. These data hint to local targeting studies on P2X7 modulation for atherothrombosis prevention/therapy. 相似文献
7.
C. Tuve' R. Potenza M. Chiorboli M.G. Grimaldi F. La Rosa F. Raimondo M. Marinelli E. Milani A. Tucciarone G. Verona Rinati M. Donato G. Faggio G. Messina S. Santangelo G. Pucella 《Diamond and Related Materials》2006,15(11-12):1986
Polycrystalline (pCVD) and single crystal (scCVD) diamond films grown from Chemical Vapour Deposition (CVD), if sufficiently pure at Raman analysis, are very good materials for beam or flux monitors inside accelerators or nuclear reactors. This is because they are very hard to damage in high radiation fields and very resistant to high temperatures. Films of pCVD diamond are, however, not so good as spectroscopy detectors due to inhomogeneities induced by their growth in grains with the consequent presence of grain boundaries which worsen their energy resolution. The latter can be significantly improved by growing scCVD diamond films onto HPHT synthetic diamond substrates. We have shown that it is possible to measure the density of defects inside diamond specimens using as probes suitable penetrating nuclear radiations. With the preliminary results reported here we'll show that, bombarding CVD diamond films grown at Roma “Tor Vergata” with energetic protons and 4He, 6Li and 12C ions produced in the accelerators of Catania laboratories, the pulse height defects are higher than those in silicon detectors and likewise well described by a power law in the deposited energy. Furthermore, we'll show that pulse heights for the same particles seem to depend on the duration of the measurement, thus exhibiting a sort of depolarization of the insulator when exposed to the electric voltage which makes it a particle detector. 相似文献
8.
Alessandro Casnati Patrizia Minari Andrea Pochini Rocco Ungaro Wilma F. Nijenhuis Feike De Jong David N. Reinhoudt 《Israel journal of chemistry》1992,32(1):79-87
The p-tert-butylcalix[6]arene hexamide 2 and syn-1,3,5–trimethoxy-2,4,6-triamide 4 were synthesized by reaction of α-chloro-N,N-diethylacetamide and the corresponding calix[6]arenes 1 and 3 , respectively. 1H NMR spectroscopy shows that 2 is a mixture of different conformations whereas 4 is fixed in a cone conformation. Extraction experiments, (S-L) and (H2O–CDCl3) with picrate salts, indicate that 2 complexes both alkali metal (1:2 complex) and guanidinium salts (1:1 complex) but 4 complexes only guanidinium (1:1 complex). Incorporated in supported liquid membranes (Accurel® / o-nitrophenyl n-octyl ether) the calixarenes 2 and 4 transport guanidinium salts. The hexamide 2 is a more efficient carrier of guanidinium but the syn-1,3,5-trimethoxy-2,4,6-triamide 4 is much more selective. Both 2 and 4 are sufficiently lipophilic to give membranes that are stable over longer periods (weeks). 相似文献
9.
Building a software architecture that meets functional requirements is a quite consolidated activity, whereas keeping high quality attributes is still an open challenge. In this paper we introduce an optimization framework that supports the decision whether to buy software components or to build them in-house upon designing a software architecture. We devise a non-linear cost/quality optimization model based on decision variables indicating the set of architectural components to buy and to build in order to minimize the software cost while keeping satisfactory values of quality attributes. From this point of view, our tool can be ideally embedded into a Cost Benefit Analysis Method to provide decision support to software architects. The novelty of our approach consists in building costs and quality attributes on a common set of decision variables related to software development. We start from a special case of the framework where the quality constraints are related to the delivery time and the product reliability, and the model solution also devises the amount of unit testing to be performed on built components. We generalize the framework formulation to represent a broader class of architectural cost-minimization problems under quality constraints, and discuss advantages and limitations of such approach. 相似文献
10.