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1.
This paper considers the problem of embedding complete binary trees into meshes using the row-column routing and obtained the following results: a complete binary tree with 2p-1 nodes can be embedded (1) with link congestion one into a 9/8√(2p9/ 8√(2p) mesh when p is even and a √( 9/82p)×√(9/ 82p) mesh when p is odd, and (2) with link congestion two into a √(2p)×√(2p) mesh when p is even, and a √(2p-1)×√(2p-1) mesh when p is odd  相似文献   

2.
To approach a simple game Δ2 of P and E = {E1, E2} with no a priori evaders' role assignment and the payoff equal to the distance to one evader at an instant of catching another, we introduce a concept of casting and study the games Δ1,2 and Δ2,1 for preassigned and Δp2 for open-loop casting procedures. Since Δp2 is reduced to Δ1,2 or Δ2,1 which, in turn, are distinguished only by their notations, we focus attention mainly on Δ1,2. According to the tenet of transition, Δ1,2 is divided into a concatenation of Δ1,2b (basic) and Δ1,2a (auxiliary) games that model the problem before and after the first instant of E1 capture. The games Δ1,2a, Δ1,2b, Δ1,2 are studied one after another with use of the Isaacs' approach extended by Berkowitz, Breakwell, Bernhard et al.  相似文献   

3.
Polyacrylamide (PAA) and amine-functionalized PAA (AFPAA) nanoparticles with disulfonated 4,7-diphenyl-1,10-phenantroline ruthenium (Ru(dpp(SO3)2)3) have been prepared. The nanoparticles produced have a hydrodynamic radius of 20–25 nm.

The amount of singlet oxygen (1O2) produced by Ru(dpp(SO3)2)3 as been measured using anthracene-9,10-dipropionic acid (ADPA). A kinetic model for the disappearance of ADPA, by steady state irradiation of Ru(dpp(SO3)2)3 at 465 nm, has been developed taking also into account a consumption not mediated by 1O2. This direct consumption of ADPA is evaluated by irradiating in the presence of NaN3 and is about 30% of the total. All the experimental results are very well described by the model developed, both for free Ru(dpp(SO3)2)3 and with this dye incorporated in the nanoparticles.

It is found that the polyacrylamide matrix does not quench the 1O2 produced, allowing it to reach the external solution of the nanoparticles and react with ADPA. When the matrix possesses amine groups, AFPAA, the amount of 1O2 that reacts with ADPA is slightly reduced, 60%, but most of the 1O2 produced can still leave the particles and react with external molecules. The particles produced may therefore be used as sources of 1O2 in photodynamic therapy (PTD) of cancers. The fact that those nanoparticles do not quench significantly the 1O2 makes possible the future development of 1O2 sensors based on PAA nanoparticles with the appropriate sensor molecule enclosed.  相似文献   


4.
A polynomial is said to be of type (p1, p2, p3) relative to a directed line in the complex plane if, counting multiplicities, it has p1 zeros to the left of, p2 zeros on, and p3 zeros to the right of the line. In this paper we determine explicitly the types of all polynomials belonging to a very restricted (but infinite) family of polynomials. A polynomial ƒ belongs to this family if and only if its coefficients are such that the polynomial ƒ*(0)ƒ(z)−ƒ(0) ƒ*(z) is a monomial; here ƒ* denotes the reflection of ƒ in the directed line.

A special case of the present result appeared in an earlier publication.  相似文献   


5.
Abstract A new setup for small-scale differential scanning calorimetry (DSC) studies based on a suspended bridge configuration is presented. The new setup has three major advantages over previously reported DSC setups: 1) superior temperature uniformity in the bridge cross section; 2) less heat loss to the surroundings by at least two orders of magnitude; and 3) a faster transient response by three orders of magnitude. This paper includes a thermal analysis to support these improvements. A major contribution of the new thermal analysis over previous reports is the inclusion of the thermal mass of the substrate in calculations, which makes thermal design more detailed, dramatically affecting accuracy and sensitivity in measurements. Furthermore, the new thermal analysis more accurately accounts for heat loss to the substrate and the surroundings in efforts to resolve suspected inconsistencies in previously reported data. Experimental validation of the new setup is presented by measuring the specific heat of thin layers of Si02 and CoFe. The specific heat of Si02 was found to be 2.2 times 106 Jm -3 K-1 which is nearly 10% different from the literature values of bulk specimens. For CoFe, the specific heat value of 3.16 x 106 Jm -3 K-1 is obtained using differential Cu/Si02 and Cu/Si02/CoFe structures compared to the value of 3.5 times 106 Jm -3 K-1 obtained using single CoFe suspended structure.  相似文献   

6.
The main contribution of this work is to present elegant broadcast-efficient protocols for permutation routing, ranking, and sorting on single-hop Mobile Radio Networks with p stations and k radio channels, denoted by MRN(p,k). Clearly, any protocol performing these tasks on n items must perform n/k broadcast rounds because each item must be broadcast at least once. We begin by presenting an optimal off-line permutation routing protocol using n /k broadcast rounds for arbitrary k, p, and n. Further, we show that optimal on-line routing can be performed in n/ k broadcast rounds, provided that either k=1 or p=n. We then go on to develop an online routing protocol that takes 2n/ k+k-1 broadcast rounds on the MRN(p,k), whenever k⩽√p/2. Using these routing protocols as basic building blocks, we develop a ranking protocol that takes 2n /k+o(n/k) broadcast rounds as well as a sorting protocol that takes 3n/k+o(n/k) broadcast rounds, provided that k ϵ o(√n) and p=n. Finally, we develop a ranking protocol that takes 3n/k+o(n/ k) broadcast rounds, as well as a sorting protocol that takes 4n/k+o(n/k) broadcast rounds on the MRN(p,k), provided that k⩽√p/2 and p ϵ o(n). Featuring very low proportionality constants, our protocols offer a vast improvement over the state of the art  相似文献   

7.
Given N matrices A1, A2,...,AN of size NtimesN, the matrix chain product problem is to compute A1timesA2times...timesAN. Given an NtimesN matrix A, the matrix powers problem is to calculate the first N powers of A, that is, A, A2, A3,..., AN. We solve the two problems on distributed memory systems (DMSs) with p processors that can support one-to-one communications in T(p) time. Assume that the fastest sequential matrix multiplication algorithm has time complexity O(Nalpha), where the currently best value of a is less than 2.3755. Let p be arbitrarily chosen in the range 1lesplesNalpha+1/(log N)2. We show that the two problems can be solved by a DMS with p processors in Tchain(N,p)=O((Nalpha+1/p)+T(p))((N2(2+1/alpha/p2/alpha)(log+p/N)1-2/alpha+log+((p log N)/Nalpha)) and Tpower (N,p)=O(Nalpha+1/p+T(p)((N2(1+1/alpha)/p2/alpha)(log+p/2 log N)1-2/alpha+(log N)2))) times, respectively, where the function log+ is defined as follows: log+ x=log x if xges1 and log+ x=1 if 0相似文献   

8.
量子化学方法研究阴离子表面活性剂在气液界面上的吸附   总被引:1,自引:1,他引:0  
用量子化学方法中的密度泛函理论,在B3LYP/6-3IG水平上,对十二烷基硫酸钠(SDS)阴离子表面活性剂与水分子形成的水合物CH3(CH211OSO3ˉ(H2O)n(n=0~7)进行结构优化和频率计算。从分子水平上研究了CH3(CH211OSO3ˉ在气液界面上与水分子的相互作用。计算结果表明:(1)7个水分子与极性头均采用1:1型和2:1型,即极性头中一个氧原子或2个氧原子与水分子以氢键形式构成水合层;(2)CH3(CH211OSO3中的氧原子与水分子中的氧原子最短氢键的键长(O-O键长)在0.27~0.31 nm之间,H…O键长在0.19~0.21 nm之间,O-H…O键角在140°~167°之间,均属于中强氢键:(3)水合物R(S-O)平均键长比表面活性剂单体分子分别增长了,说明形成水合物后S-O间的键减弱;(4)结合能D0从64.04 kJ/mol增加到.428.29 kJ/mol,说明随着水分子数的增加,所获得的7种水合物的稳定性依次增强,表明最终形成的水合层是稳定的:(5)随着水分子数增加疏水基链长收缩,亲水基总电荷增加,C12-O13-S14的键角增大;(6)由于烷烃链带有了弱电荷,使胶束内核带有了部分极性,此种极性介于烷烃油相和水相的极性之间,利于表面活性剂在溶液中的聚集。  相似文献   

9.
In Georgiou and Smith (1992), the following question was raised: Consider a linear, shift-invariant system on L2[0, ∞). Let the graph of the system have Fourier transform (MN)H2 (i.e., the system has a transfer function P=N/M) where M, N are elements of CA={f∈H: f is continuous on the compactified right-half plane}. Is it possible to normalize M and N (i.e., to ensure |M|2+|N|2=1) in CA? The author shows by example that this is not always possible  相似文献   

10.
We consider stochastic nonaffine nonlinear control systems xt =x0+∫0t f(xs,u) ds+∫0t g(xs,u) dωs (written in the sense of Ito), ω being a standard Wiener process, for which we give a sufficient condition for global stabilization by a bounded smooth state feedback that is explicitly given. This condition generalizes the well-known Jurdjevic-Quinn result for deterministic affine control systems  相似文献   

11.
Bidimensional wavelet bases are constructed by means of McClellan's transformation applied to a pair of one-dimensional biorthogonal wavelet filters. It is shown that under some conditions on the transfer function F12) associated to the McClellan transformation and on the dilation matrix D, it is possible to construct symmetric compactly supported biorthogonal wavelet bases of L2(R2). Finally, the construction method is illustrated by means of numerical examples.  相似文献   

12.
LaFEO3 and CaxLa1−xFeO3 ceramic powders have been prepared by the coprecipitation method from La(NO3)3, Fe(NO3)3 and Ca(NO3)2 aqueous solutions. The orthorhombic perovskite phases of LaFeO3 and CaxLa1−xFeO3 are characterized by X-ray diffraction patterns. The sensors fabricated with those powders have high sensitivity to alcohol. Partial substitution of La3+ in LaFeO3 with Ca2+ can enhance the sensitivity of the materials to reducing gases. The resistance of an LaFeO3 sensor in air, vacuum and alcohol-containing air has been measured. Complex impedance spectroscopy has been used to try and analyse the gas-sensing mechanism. According to the experimental results, it can be deduced that the surface adsorptive and lattice oxygen govern the sensing properties of LaFeO3 and CaxLa1−xFeO3 ceramics.  相似文献   

13.
Raman spectroscopy has exhibited the C–H stretch (A1 mode) frequency ν1 of hydrated methanes at 2915 cm−1 for the 512 cage and 2905 cm−1 for the 51262 cage. These values are lower than the frequency of 2916.5 cm−1 in gaseous methane. In this paper, we theoretically examine the Raman spectra observed in methane hydrate by normal mode analysis using the independent molecule model. By a breakdown of the symmetry, the four frequencies in modes A1, E, T2 and T2 observed in gaseous methane are separated into nine frequencies in the hydrate. It is necessary to consider the anharmonic potential energy within methane and hydrogen bonding between methane hydrogen and water oxygen in order to get a result in qualitative agreement with experiment. The frequency in the 51262 cage is shifted downward in comparison to the one in 512, and the frequencies in the both cages are also shifted downward compared with the frequencies in gas. Calculations are also reported for the isotopic methane (CD4, 13CH4) hydrates.  相似文献   

14.
β-Cyclodextrins functionalized by different moieties that were tethered to a single 6-deoxyaminoglucose unit were investigated with respect to their suitability for sensor applications. Derivatizing the cyclodextrins with hydrophobic moieties like dipalmitoylglycerol and cholesterol allowed us to study packing density and orientation of the cyclodextrin tori at the air–water interface. From the pressure-area isotherms, it was concluded that the cyclodextrins are positioned towards the water subphase, with their molecular axis predominately parallel to the interface. By introducing a disulfide group, we managed to immobilize cyclodextrins on gold surfaces via self-assembly. MALDI mass spectrometry (MALDI MS) and XPS confirmed that the molecules are chemisorbed on the gold substrate displaying high surface coverage as determined by means of impedance spectroscopy. The inclusion of various charged guest molecules was monitored by changes in the charge transfer resistance of the redox couple [Fe(CN)6]3−/[Fe(CN)6]4−. The charge transfer resistance is sensitive to the surface potential, which leads to either repulsion or attraction of the redox active species.  相似文献   

15.
The orientation position errors of an object's coordinate frame are determined when the offset of image centre and lens distortion are not included in the calibration process. The orientation and position errors are [(u0)2 + (v0)2]0.5/f and [(u20+v20)T2z + (u20T2z + v20Ty2)]0.5/f, respectively, where f is the focal length, (u0, v0) is the offset of image centre and (Tx Ty Tz) is the position of an object. We also obtain the following conclusions: (a) The offset of image centre has little effect on the determinations of the position and orientation of a coordinate frame; (b) the lens distortion will not dramatically change the position and orientation of a coordinate frame; (c) the scale factor has a great effect on the position of a coordinate frame, and on the accuracy of measurement; (d) the offset of image centre is more sensitive than the lens distortion on the determinations of the position and orientation of a coordinate frame. Finally, some experimental results are given to demonstrate the theoretical analysis given in this paper.  相似文献   

16.
A digital disc is the set of all integer points inside some given disc. Let DN be the number of different digital discs consisting of N points (different up to translation). The upper bound D N = O(N2) was shown recently; no corresponding lower bound is known. In this paper, we refine the upper bound to DN = O(N), which seems to be the true order of magnitude, and we show that the average DN = D1 + D2 ... DN)/N has upper and lower bounds which are of polynomial growth in N  相似文献   

17.
We present efficient parallel matrix multiplication algorithms for linear arrays with reconfigurable pipelined bus systems (LARPBS). Such systems are able to support a large volume of parallel communication of various patterns in constant time. An LARPBS can also be reconfigured into many independent subsystems and, thus, is able to support parallel implementations of divide-and-conquer computations like Strassen's algorithm. The main contributions of the paper are as follows. We develop five matrix multiplication algorithms with varying degrees of parallelism on the LARPBS computing model; namely, MM1, MM 2, MM3, and compound algorithms C1(ϵ)and C2(δ). Algorithm C1(ϵ) has adjustable time complexity in sublinear level. Algorithm C2(δ) implies that it is feasible to achieve sublogarithmic time using σ(N3) processors for matrix multiplication on a realistic system. Algorithms MM3, C1(ϵ), and C2(δ) all have o(𝒩3) cost and, hence, are very processor efficient. Algorithms MM1, MM3, and C1(ϵ) are general-purpose matrix multiplication algorithms, where the array elements are in any ring. Algorithms MM2 and C2(δ) are applicable to array elements that are integers of bounded magnitude, or floating-point values of bounded precision and magnitude, or Boolean values. Extension of algorithms MM 2 and C2(δ) to unbounded integers and reals are also discussed  相似文献   

18.
A closed-form expression has been reported in the literature for LN, the number of digital line segments of length N that correspond to lines of the form y=ax+β, O⩽α, β<1. The authors prove an asymptotic estimate for LN that might prove useful for many applications, namely, LN=N 32+O(N2 log N). An application to an image registration problem is given  相似文献   

19.
C. Colinet  A. Pasturel 《Calphad》2002,26(4):563-571
The relative stabilities of L12, D022, D023, 21, and 3 structures in the Pd3V, Pt3V, Rh3V, and Pt3Ti compounds are investigated employing the Vienna ab initio simulation package. In the pseudobinary Pd3xRh3(1−x)V, Pt3xRh3(1−x)V, and Pt3VxTi(1−x) alloys, the energy differences from L12 of D022, D023, 21, and 3 structures are assumed to be linear as function of the number of electrons per atom. At T=0K, the resulting energy diagram shows that the equilibrium between the limiting binary phases is the most stable state. At high temperature, the Gibbs energy curves are computed assuming a Bragg and Williams entropy of mixing in the pseudobinary sections. The D023 and 21 structures are stabilized in the pseudobinary Pd3xRh3(1−x)V, Pt3xRh3(1−x)V, and Pt3VxTi(1−x) alloys. The phase diagram between the various structures is calculated in each pseudobinary section and compared with the experimental one.  相似文献   

20.
为探讨二甲基二硫代氨基甲酸盐螯合重金属离子的作用机理,本文采用密度泛函理论,在B3LYP/6-31++G(d,p)和B3LYP/LanL2DZ混合基组水平上,分别计算了二甲基二硫代氨基甲酸离子(DDC-)和铬、铜、钴、锌、铁、镉6种重金属离子形成配合物的前线轨道能级、配位能△E、考虑基组重叠误差后的配位能△EBSSE、零点振动能校正后的配位能△EZPE及自然电荷分布。研究结果表明:上述二甲基二硫代氨基甲酸配合物的稳定性与能级差△ε及配位能△EBSSE、△EZPE的绝对值密切相关,△ε及△EBSSE、△EZPE的绝对值越大,配合物越稳定。6种二甲基二硫代氨基甲酸重金属配合物的稳定性由大到小的顺序为:[CrDDC]2+>[CuDDC]+>[CoDDC]+>[ZnDDC]+>[FeDDC]+>[CdDDC]+。在形成配合物的过程中,电子从配体DDC-流向重金属离子,电荷转移越多,配位能的绝对值越大。  相似文献   

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