We investigate a general class of quantum key distribution (QKD) protocols using one-way classical communication. We show that full security can be proven by considering only collective attacks. We derive computable lower and upper bounds on the secret-key rate of those QKD protocols involving only entropies of two-qubit density operators. As an illustration of our results, we determine new bou...

Designing a movable spatial four-bar mechanism that guides a coupler system through three given poses is an old and well known problem. The resulting mechanism has to be overconstrained and is called Bennett mechanism. We give a completely new solution of this problem using kinematic mapping and multidimensional geometry. This approach provides a new insight in the problem. First of all it show...

Let X be the Bennett-Lutzer’s space and Y be the space obtained from X by shrinking the set of all rational numbers to a point. In his book, G.Gao claimed that the space Y is compact. In this paper, we prove that Y is neither countably compact nor Lindelöf, which shows that G.Gao’s claim is not true. Moreover, we prove that Y is strongly paracompact. As an application of this result, we obtain ...

The problem of aggregation processes in alignments is the subject of a paper published recently in a Statistical Physics Journal (Physica A230, 174-188, 1996). Two models are presented and discussed in that paper. First the energy landscape model proposed by Axelrod and Bennett (B. J. Pol. S. 23, 211-233, 1993), is analysed. The model is shown not to include most of its claimed results. Then a ...

1. Nebeker JR, Virmani R, Bennett CL, et al. Hypersensitivity cases associated with drug-eluting coronary stents: a review of available cases from the Research on Adverse Drug events And Reports (RADAR) project. J Am Coll Cardiol 2006;47:175–81. 2. Bennett CL, Nebeker JR, Lyons EA, et al. The Research on Adverse Drug events And Reports (RADAR) project. JAMA 2005;293: 2131– 40. 3. Nebeker JR, Ba...

The notion of an effect algebra was presented by Foulis and Bennett in (Foulis, Bennett, [3] 1994). The definition was motivated by giving an algebraic description of a logic of quantum effects E(H), i.e. the set of all positive self-adjoint operators between zero and identity operator I in a separable complex Hilbert space H. On E(H) was defined a partial operation A ⊕ B = A + B iff A + B ≤ I ...

The following conjecture was posed by Axler and Shields. Let {xn} be a monotone decreasing sequence of nonnegative numbers, C the Cesáro matrix of order one. What is the best constant K for which ‖Cx‖2 ≥ K‖x‖2 for all such sequences {xn}? Lyons [3] determined that the best constant is π/ √ 6. This result was extended to p spaces for p > 1 by Bennett [1]. In [1], Bennett established the followin...

The profile of a Bennett hole, induced by a laser field, in the ionic distribution of a collisional plasma is calculated. The influence of Chandrasekhar’s dependence of the coefficients of velocity space transport on the profile is included in the calculation for the first time. It is found that the hole narrows down as the field-detuning frequency increases. The physical cause for this effect ...

A central goal in information theory and cryptography is finding simple characterizations of optimal communication rates under various restrictions and security requirements. Ideally, the optimal key rate for a quantum key distribution (QKD) protocol would be given by a single-letter formula involving optimization over a single use of an effective channel. We explore the possibility of such a f...

In this article, a testing procedure based on computational approach testis proposed for the equality of coe¢ cients of variation in k normal populations. We compare this procedure to some of the existing tests; the likelihood ratio, modi…ed Bennett’s, score, generalized p-value tests in terms of the estimated type I error rates and powers by using Monte Carlo simulation. Furthermore, applicati...