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1.
In this paper, we extend a temporal defeasible logic with a modal operator Committed to formalize commitments that agents undertake as a consequence of communicative actions (speech acts) during dialogues. We represent commitments as modal sentences. The defeasible dual of the modal operator Committed is a modal operator called Exempted. The logical setting makes the social-commitment based semantics of speech acts verifiable and practical; it is possible to detect if, and when, a commitment is violated and/or complied with. One of the main advantages of the proposed system is that it allows for capturing the nonmonotonic behavior of the commitments induced by the relevant speech acts.  相似文献   

2.
In the literature on logics of imperfect information it is often stated, incorrectly, that the Game-Theoretical Semantics of Independence-Friendly (IF) quantifiers captures the idea that the players of semantical games are forced to make some moves without knowledge of the moves of other players. We survey here the alternative semantics for IF logic that have been suggested in order to enforce this “epistemic reading” of sentences. We introduce some new proposals, and a more general logical language which distinguishes between “independence from actions” and “independence from strategies”. New semantics for IF logic can be obtained by choosing embeddings of the set of IF sentences into this larger language. We compare all the semantics proposed and their purported game-theoretical justifications, and disprove a few claims that have been made in the literature.  相似文献   

3.
This paper presents methods for synthesizing Σ-automata from specifications in the language LP with deterministic semantics and in the language LF with nondeterministic semantics. These methods are based on the equivalent transformation of a formula of the form ?tF (t) into the so-called normal form whose structure corresponds to the state transition graph of a specified Σ-automaton.  相似文献   

4.
In this paper, based on a complete residuated lattice L, we introduce the definitions of L-quantum spaces and continuous mappings. Then we establish an adjunction between the category of stratified L-quantum spaces and the opposite category of two-sided L-quantales. We also prove that the category of sober L-quantum spaces is dually equivalent to the category of spatial two-sided L-quantales.  相似文献   

5.
The goal of this paper is to focus on the notions of merotopy and also merotopology in the soft universe. First of all, we propose L-soft merotopic (nearness) spaces and L-soft guild. Then, we study binary, contigual, regular merotopic spaces and also relations between them. We show that the category of binary L-soft nearness spaces is bireflective in the category of L-soft nearness spaces. Later, we define L-approach soft merotopological (nearness) spaces by giving several examples. Finally, we define a simpler characterization of L-approach soft grill merotopological space called grill-determined L-approach soft merotopological space. We investigate the categorical structures of these notions such as we prove that the category of grill-determined L-approach soft merotopological spaces is a topological category over the category of L-soft topological spaces. At the end, we define a partial order on the family of all L-approach soft grill merotopologies and show that this family is a completely distributive complete lattice with respect to the defined partial order.  相似文献   

6.
Constructions of quantum caps in projective space PG(r, 4) by recursive methods and computer search are discussed. For each even n satisfying \(n\ge 282\) and each odd z satisfying \(z\ge 275\), a quantum n-cap and a quantum z-cap in \(PG(k-1, 4)\) with suitable k are constructed, and \([[n,n-2k,4]]\) and \([[z,z-2k,4]]\) quantum codes are derived from the constructed quantum n-cap and z-cap, respectively. For \(n\ge 282\) and \(n\ne 286\), 756 and 5040, or \(z\ge 275\), the results on the sizes of quantum caps and quantum codes are new, and all the obtained quantum codes are optimal codes according to the quantum Hamming bound. While constructing quantum caps, we also obtain many large caps in PG(r, 4) for \(r\ge 11\). These results concerning large caps provide improved lower bounds on the maximal sizes of caps in PG(r, 4) for \(r\ge 11\).  相似文献   

7.
This paper forms part of an ongoing investigation to examine the quantum prediction that isolated baryons and electrons in the deep gravity wells of galaxy halos should exhibit reduced interaction cross-sections by virtue of the composition of the gravitational eigenspectra of their wave functions, and thereby identify a possible mechanism responsible for the origin of dark matter, without resorting to new physics or unknown particles. Relevant to this investigation are the electromagnetic state-to-state transition rates of charged particles occupying these gravitational eigenstates (EinsteinA coefficients), and, in the present work, we examine trends in these rates and net state lifetimes for particles in 1/r potential wells for values of the principal quantum number n and the angular momentum quantum number l. We find that transition rates decrease with increasing n and l, and that the rate is more steeply dependent on l when the quantum parameter Δp (≡ Δn ? Δl) is greater, in agreement with earlier work. It is also found that there is an empirical relationship between the total state lifetime τ and the eigenvalues n and l, which is given by τn α l β , where α ≈ 3 and β ≈ 2. The results apply equally to electrical potential wells, where the phenomena of reduced cross-sections and long radiative lifetimes is well known in the case of the Rydberg states of electrons in atoms. More importantly, in the case of gravitational eigenstates discussed here, the quantum prediction of low Einstein A (and therefore B) coefficients ofmany of the stateto-state transitions will mean that a particle whose eigenspectral composition consists of many of these weakly interacting states will be less likely to undergo scattering processes such as Compton scattering. Trends in the Einstein coefficients over the range of component eigenstates are required for calculating the net visibility and interaction rates of the generalized wave functions representing charged particles in macroscopic gravitational fields.  相似文献   

8.
This paper studies the problem of state feedback H control for singular systems through delta operator approach. A necessary and sufficient condition is presented such that a singular delta operator system is admissible with a prescribed H performance, which can provide a unified framework of the existing H performance analysis results for both continuous case and discrete case. The existence condition and explicit expression of a desirable H controller are also obtained for singular delta operator systems. The proposed design method can be used for both singular continuous systems and singular discrete systems directly. The corresponding design procedures, which simplify the classical approaches, are discussed and presented. All obtained conditions in this paper are in the form of strict linear matrix inequalities whose feasible solutions can be found by standard linear programming method. Numerical examples are provided to illustrate the effectiveness of the theoretical results obtained in this paper.  相似文献   

9.
So far, very little is known about local indistinguishability of multipartite orthogonal product bases except some special cases. We first give a method to construct an orthogonal product basis with n parties each holding a \(\frac{1}{2}(n+1)\)-dimensional system, where \(n\ge 5\) and n is odd. The proof of the local indistinguishability of the basis exhibits that it is a sufficient condition for the local indistinguishability of an orthogonal multipartite product basis that all the positive operator-valued measure elements of each party can only be proportional to the identity operator to make further discrimination feasible. Then, we construct a set of n-partite product states, which contains only 2n members and cannot be perfectly distinguished by local operations and classic communication. All the results lead to a better understanding of the phenomenon of quantum nonlocality without entanglement in multipartite and high-dimensional quantum systems.  相似文献   

10.
A (t, n) threshold quantum secret sharing (QSS) is proposed based on a single d-level quantum system. It enables the (t, n) threshold structure based on Shamir’s secret sharing and simply requires sequential communication in d-level quantum system to recover secret. Besides, the scheme provides a verification mechanism which employs an additional qudit to detect cheats and eavesdropping during secret reconstruction and allows a participant to use the share repeatedly. Analyses show that the proposed scheme is resistant to typical attacks. Moreover, the scheme is scalable in participant number and easier to realize compared to related schemes. More generally, our scheme also presents a generic method to construct new (t, n) threshold QSS schemes based on d-level quantum system from other classical threshold secret sharing.  相似文献   

11.
In the setting of session behaviours, we study an extension of the concept of compliance when a disciplined form of backtracking and of output skipping is present. After adding checkpoints to the syntax of session behaviours, we formalise the operational semantics via an LTS, and define natural notions of checkpoint compliance and sub-behaviour, which we prove to be both decidable. Then we extend the operational semantics with skips and we show the decidability of the obtained compliance.  相似文献   

12.
The uncertainty principle in quantum mechanics is a fundamental relation with different forms, including Heisenberg’s uncertainty relation and Schrödinger’s uncertainty relation. In this paper, we prove a Schrödinger-type uncertainty relation in terms of generalized metric adjusted skew information and correlation measure by using operator monotone functions, which reads,
$$\begin{aligned} U_\rho ^{(g,f)}(A)U_\rho ^{(g,f)}(B)\ge \frac{f(0)^2l}{k}\left| \mathrm {Corr}_\rho ^{s(g,f)}(A,B)\right| ^2 \end{aligned}$$
for some operator monotone functions f and g, all n-dimensional observables AB and a non-singular density matrix \(\rho \). As applications, we derive some new uncertainty relations for Wigner–Yanase skew information and Wigner–Yanase–Dyson skew information.
  相似文献   

13.
The Shor algorithm is effective for public-key cryptosystems based on an abelian group. At CRYPTO 2001, Paeng (2001) presented a MOR cryptosystem using a non-abelian group, which can be considered as a candidate scheme for post-quantum attack. This paper analyses the security of a MOR cryptosystem based on a finite associative algebra using a quantum algorithm. Specifically, let L be a finite associative algebra over a finite field F. Consider a homomorphism φ: Aut(L) → Aut(H)×Aut(I), where I is an ideal of L and H ? L/I. We compute dim Im(φ) and dim Ker(φ), and combine them by dim Aut(L) = dim Im(φ)+dim Ker(φ). We prove that Im(φ) = StabComp(H,I)(μ + B2(H, I)) and Ker(φ) ? Z1(H, I). Thus, we can obtain dim Im(φ), since the algorithm for the stabilizer is a standard algorithm among abelian hidden subgroup algorithms. In addition, Z1(H, I) is equivalent to the solution space of the linear equation group over the Galois fields GF(p), and it is possible to obtain dim Ker(φ) by the enumeration theorem. Furthermore, we can obtain the dimension of the automorphism group Aut(L). When the map ? ∈ Aut(L), it is possible to effectively compute the cyclic group 〈?〉 and recover the private key a. Therefore, the MOR scheme is insecure when based on a finite associative algebra in quantum computation.  相似文献   

14.
We present Clafer (class, feature, reference), a class modeling language with first-class support for feature modeling. We designed Clafer as a concise notation for meta-models, feature models, mixtures of meta- and feature models (such as components with options), and models that couple feature models and meta-models via constraints (such as mapping feature configurations to component configurations or model templates). Clafer allows arranging models into multiple specialization and extension layers via constraints and inheritance. We identify several key mechanisms allowing a meta-modeling language to express feature models concisely. Clafer unifies basic modeling constructs, such as class, association, and property, into a single construct, called clafer. We provide the language with a formal semantics built in a structurally explicit way. The resulting semantics explains the meaning of hierarchical models whereby properties can be arbitrarily nested in the presence of inheritance and feature modeling constructs. The semantics also enables building consistent automated reasoning support for the language: To date, we implemented three reasoners for Clafer based on Alloy, Z3 SMT, and Choco3 CSP solvers. We show that Clafer meets its design objectives using examples and by comparing to other languages.  相似文献   

15.
Principal component analysis is a multivariate statistical method frequently used in science and engineering to reduce the dimension of a problem or extract the most significant features from a dataset. In this paper, using a similar notion to the quantum counting, we show how to apply the amplitude amplification together with the phase estimation algorithm to an operator in order to procure the eigenvectors of the operator associated to the eigenvalues defined in the range \(\left[ a, b\right] \), where a and b are real and \(0 \le a \le b \le 1\). This makes possible to obtain a combination of the eigenvectors associated with the largest eigenvalues and so can be used to do principal component analysis on quantum computers.  相似文献   

16.
In this paper, we consider mixed H 2/H control problems for linear infinite-dimensional systems. The first part considers the state feedback control for the H 2/H control problems of linear infinite-dimensional systems. The cost horizon can be infinite or finite time. The solutions of the H 2/H control problem for linear infinitedimensional systems are presented in terms of the solutions of the coupled operator Riccati equations and coupled differential operator Riccati equations. The second part addresses the observer-based H 2/H control of linear infinite-dimensional systems with infinite horizon and finite horizon costs. The solutions for the observer-based H 2/H control problem of linear infinite-dimensional systems are represented in terms of the solutions of coupled operator Riccati equations. The first-order partial differential system examples are presented for illustration. In particular, for these examples, the Riccati equations are represented in terms of the coefficients of first-order partial differential systems.  相似文献   

17.
In quantum cryptography, a one-way permutation is a bounded unitary operator \(U:\mathcal {H} \rightarrow \mathcal {H}\) on a Hilbert space \(\mathcal {H}\) that is easy to compute on every input, but hard to invert given the image of a random input. Levin (Probl Inf Transm 39(1):92–103, 2003) has conjectured that the unitary transformation \(g(a,x)=(a,f(x)+ax)\), where f is any length-preserving function and \(a,x \in \hbox {GF}_{{2}^{\Vert x\Vert }}\), is an information-theoretically secure operator within a polynomial factor. Here, we show that Levin’s one-way permutation is provably secure because its output values are four maximally entangled two-qubit states, and whose probability of factoring them approaches zero faster than the multiplicative inverse of any positive polynomial poly(x) over the Boolean ring of all subsets of x. Our results demonstrate through well-known theorems that existence of classical one-way functions implies existence of a universal quantum one-way permutation that cannot be inverted in subexponential time in the worst case.  相似文献   

18.
FALGOL (Formal ALGOrithmic Language) is a fundamental theoretical model of high-level operational languages with unrestricted program object hierarchy. This model formalizes binding, assignment, substitution, and recursion; moreover, the principle of dynamic binding is implemented in the model in contrast to other formal systems of this sort, which makes FALGOL appropriate to specify the most difficultly formalized concepts in modern object programming languages.  相似文献   

19.
20.
Uncertainty principle significantly provides a bound to predict precision of measurement with regard to any two incompatible observables, and thereby plays a nontrivial role in quantum precision measurement. In this work, we observe the dynamical features of the quantum-memory-assisted entropic uncertainty relations (EUR) for a pair of incompatible measurements in an open system characterized by local generalized amplitude damping (GAD) noises. Herein, we derive the dynamical evolution of the entropic uncertainty with respect to the measurement affecting by the canonical GAD noises when particle A is initially entangled with quantum memory B. Specifically, we examine the dynamics of EUR in the frame of three realistic scenarios: one case is that particle A is affected by environmental noise (GAD) while particle B as quantum memory is free from any noises, another case is that particle B is affected by the external noise while particle A is not, and the last case is that both of the particles suffer from the noises. By analytical methods, it turns out that the uncertainty is not full dependent of quantum correlation evolution of the composite system consisting of A and B, but the minimal conditional entropy of the measured subsystem. Furthermore, we present a possible physical interpretation for the behavior of the uncertainty evolution by means of the mixedness of the observed system; we argue that the uncertainty might be dramatically correlated with the systematic mixedness. Furthermore, we put forward a simple and effective strategy to reduce the measuring uncertainty of interest upon quantum partially collapsed measurement. Therefore, our explorations might offer an insight into the dynamics of the entropic uncertainty relation in a realistic system, and be of importance to quantum precision measurement during quantum information processing.  相似文献   

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