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101.
102.
Costas Courcoubetis Panagiotis Konstantopoulos Jean Walrand Richard R. Weber 《Queueing Systems》1989,5(1-3):37-54
Consider a production system that consists ofm machines each of which can produce parts ofn types. When machinek is used, it produces a part of typei with probabilityp
ki
. Requests arrive for parts, one at a time. With probability
i
an arriving request is for a part of typei. The requests must be served without waiting. Thus, if a requested part is not available, it must be produced. We find necessary and sufficient conditions for the existence of a strategy (a choice of the machines to be used) which makes the inventory of parts stable and we provide such a strategy.Two variations of this model are also considered: the case of batch arrivals of requests, and that of a system where the requests can be queued. 相似文献
103.
Summary In this paper we study the Dirichlet problem, for second order, linear elliptic partial differential equations with discontinuous coefficients in unbounded domains. We obtain some results about existence and uniqueness of the solution in W2().
Lavoro eseguito nell'ambito del G.N.A.F.A. del C.N.R. 相似文献
Lavoro eseguito nell'ambito del G.N.A.F.A. del C.N.R. 相似文献
104.
Ammar R Ball RC Banerjee S Bhat PC Bosetti P Bromberg C Canough GE Coffin T Dershem TO Dixon RL Fenker HC Ganguli SN Gensch U Girtler P Goshaw AT Grard F Gurtu A Hamilton C Henri VP Hernandez JJ Hrubec J Iori M Jones LW Kuhn D Knauss D Leedom ID Legros P Lemonne J Leutz H Liu X Malhotra PK Marraffino JM Mendez GE Miller R Naumann T Nguyen A Nowak H Pilette P Poirier J Poppleton A Raghavan R Rasner K Reucroft S Robertson WJ Roe BP Roth A Senko M Struczinski W Subramanian A Touboul MC Vonck B 《Physical review letters》1988,61(19):2185-2188
105.
106.
107.
J. Engels J. Fingberg K. Redlich H. Satz M. Weber 《Zeitschrift fur Physik C Particles and Fields》1989,42(2):341-347
InSU(2) lattice gauge theory, we study deviations from ideal gas behaviour near the deconfinement point. On lattices of sizeN σ 3 ×4,N σ=8, 12, 18 and 26, we calculate the quantityΔ≡(ε?3P)/T 4. It increases sharply just aboveT c , peaks atT/T c =1.15 ±0.05 and then drops quickly. This form of behaviour is shown to be the consequence of a second order phase transition. Dynamically it could arise because just aboveT c , the low momentum states of the system are remnant massive modes rather than deconfined massless gluons. 相似文献
108.
109.
Nanoscale organization of the pathogen receptor DC-SIGN mapped by single-molecule high-resolution fluorescence microscopy. 总被引:3,自引:0,他引:3
Bärbel I. de Bakker Dr. Frank de Lange Dr. Alessandra Cambi Dr. Jeroen P. Korterik Erik M. H. P. van Dijk Dr. Niek F. van Hulst Prof. Carl G. Figdor Prof. Maria F. Garcia‐Parajo Prof. 《Chemphyschem》2007,8(10):1473-1480
DC-SIGN, a C-type lectin exclusively expressed on dendritic cells (DCs), plays an important role in pathogen recognition by binding with high affinity to a large variety of microorganisms. Recent experimental evidence points to a direct relation between the function of DC-SIGN as a viral receptor and its spatial arrangement on the plasma membrane. We have investigated the nanoscale organization of fluorescently labeled DC-SIGN on intact isolated DCs by means of near-field scanning optical microscopy (NSOM) combined with single-molecule detection. Fluorescence spots of different intensity and size have been directly visualized by optical means with a spatial resolution of less than 100 nm. Intensity- and size-distribution histograms of the DC-SIGN fluorescent spots confirm that approximately 80 % of the receptors are organized in nanosized domains randomly distributed on the cell membrane. Intensity-size correlation analysis revealed remarkable heterogeneity in the molecular packing density of the domains. Furthermore, we have mapped the intermolecular organization within a dense cluster by means of sequential NSOM imaging combined with discrete single-molecule photobleaching. In this way we have determined the spatial coordinates of 13 different individual dyes, with a localization accuracy of 6 nm. Our experimental observations are all consistent with an arrangement of DC-SIGN designed to maximize its chances of binding to a wide range of microorganisms. Our data also illustrate the potential of NSOM as an ultrasensitive, high-resolution technique to probe nanometer-scale organization of molecules on the cell membrane. 相似文献
110.
Maria Lalia-Kantouri 《Transition Metal Chemistry》1996,21(6):491-493
Summary Reaction of Cu(OAc)2, 4-(1H)-pyridone (LH) and Dy or Gd nitrate in MeOH resulted in the formation of the heterometallic complexes [Cu2LnL2(LH)2(NO3)(OH)4· xH2O], Ln = Dy (1) or Gd (2). Reaction of Cu(OH)2 with 4-(1H)-pyridone and Dy(NO3)3 in DMF resulted in the formation of the heterometallic compound [Cu2DyL2(LH)2(NO3)2(OH)3·DMF] (3). The Cu complexes [Cu(OAc)L]2 and [CuL2·DMF]
x
have also been prepared from the reaction of 4-(1H)-pyridone with Cu2+ in MeOH and DMF, respectively. All the complexes were characterized by elemental analyses, and i.r. and X-band e.s.r. spectroscopies. 相似文献