融合Graph state LSTM与注意力机制的跨句多元关系抽取

已有的跨句多元关系抽取工作将输入文本表示为集成句内和句间依赖关系的复杂文档图,但图中包含的噪声信息会影响关系抽取的效果。针对这种情况,该文利用Graph state LSTM获得上下文信息,再分别利用词级注意力机制或位置感知的注意力机制,自动聚焦在对关系抽取起到决定性作用的关键词上,降低噪声信息的影响。并且比较了两种注意力机制对使用Graph state LSTM进行关系抽取的影响。通过在一个重要的精确医学数据集上进行实验,验证了该文所提出模型的有效性。

Feasible schemes for preparing all five-photon graph states

We propose feasible experimental schemes for preparing all five-photon graph states. Our schemes require only linear optical elements, photon detectors and post-selection, which are available in current experiment so that these schemes are within the reach of the current technology.

Generation of various multiatom entangled graph states via resonant interactions

In this paper, a scheme for generating various multiatom entangled graph states via resonant interactions is proposed. We investigate the generation of various four-atom graph states first in the ideal case and then in the case in which the cavity decay and atomic spontaneous emission are taken into consideration in the process of interaction. More importantly, we improve the possible distortion of the graph states coming from cavity decay and atomic spontaneous emission by performing appropriate unitary transforms on atoms. The generation of multiatom entangled graph states is very important for constructing quantum one-way computer in a fault-tolerant manner. The resonant interaction time is very short, which is important in the sense of decoherence. Our scheme is easy and feasible within the reach of current experimental technology.

Feasible schemes for preparation of all five-atom graph states

We propose feasible schemes for preparation of all five-atom graph states by cavity quantum electrodynamics （QED）. Our schemes require only the atom-cavity interaction with a large detuning which is available in current experiment so that these schemes are within the reach of the current technology.

Measures of genuine multipartite entanglement for graph states

Graph states are special multipartite entangled states that have been proven useful in a variety of quantum information tasks. We address the issue of characterizing and quantifying the genuine multipartite entanglement of graph states up to eight qubits. The entanglement measures used are the geometric measure, the relative entropy of entanglement, and the logarithmic robustness, have been proved to be equal for the genuine entanglement of a graph state. We provide upper and lower bounds as well as an iterative algorithm to determine the genuine multipartite entanglement.

Improved frequency standard via weighted graph states

We study the spin squeezing property of weighted graph states,which can be used to improve sensitivity in interferometry.We study the time evolution of spin squeezing under local decoherence acting independently on each qubit.Based on the analysis,the spin squeezing of the weighted graph states is somehow robust in the presence of decoherence and the decoherence limit in the improvement of the interferometric sensitivity is still achievable.Furthermore,one can obtain the optimal improvement of sensitivity by tuning the weighted of each edges of the weighted graph state.

Representations of Graph States with Neural Networks

Quantum many-body problem(QMBP)has become a hot topic in high energy physics and condensed matter physics.With the exponential increasing of the dimension of the Hilbert space,it becomes a big challenge to solve the QMBP even with the most powerful computers.With the rapid development of machine learning,artificial neural networks provide a powerful tool to represent or approximate quantum many-body states.In this paper,we aim to construct explicitly the neural network representations of graph states,without stochastic optimization of the network parameters.Our method shows constructively that all graph states can be represented precisely by proper neural networks originated from[Science,355,602(2017)]and formulated in[Sci.China-Phys.Mech.Astron.,63,210312(2020)].

The entanglement of several graph states

We exactly evaluate the entanglement of a six vertex and a nine vertex graph states which correspond to non ＂two-colorable＂ graphs. The upper bound of entanglement for five vertex ring graph state is improved to 2.9275, less than the upper bound determined by local operations and classical communication. An upper bound of entanglement is proposed based on the definition of graph state.

Neural network representations of quantum many-body states

Machine learning is currently the most active interdisciplinary field having numerous applications;additionally,machine-learning techniques are used to research quantum many-body problems.In this study,we first propose neural network quantum states(NNQSs)with general input observables and explore a few related properties,such as the tensor product and local unitary operation.Second,we determine the necessary and sufficient conditions for the representability of a general graph state using normalized NNQS.Finally,to quantify the approximation degree of a given pure state,we define the best approximation degree using normalized NNQSs.Furthermore,we observe that some 7V-qubit states can be represented by a normalized NNQS,such as separable pure states,Bell states and GHZ states.

A Loop-Based Apparatus for At-Speed Self-Testing

At-speed testing using external tester requires an expensive equipment, thus built-in self-test (BIST) is an alternative technique due to its ability to perform on-chip at-speed self-testing. The main issue in BIST for at-speed testing is to obtain high delay fault coverage with a low hardware overhead. This paper presents an improved loop-based BIST scheme, in which a configurable MISR (multiple-input signature register) is used to generate test-pair sequences. The structure and operation modes of the BIST scheme are described. The topological properties of the state-transit ion- graph of t he proposed B IS T scheme are analyzed. B ased on it, an approach to design and efficiently implement the proposed BIST scheme is developed. Experimental results on academic benchmark circuits are presented to demonstrate the effectiveness of the proposed BIST scheme as well as the design approach.

Program Monitoring Based on Automaton Simulation

To check whether a program behaves in expectation, program monitoring systems are used for intrusion detection. This article presents a program monitoring system using automaton simulation based on the state graphs extracted from C programs through static analysis. For complete state graph construction, a pointer alias analysis method is proposed to solve the function pointers for obtaining actual control flows. After compiling, pro- grams are instrumented with probes to report the internal states when they are running. A program monitor is built in the kernel of Linux system, which monitors the states of programs from probes and checks the paths of execution. This monitoring system could respond to the abnormal behaviors immediately to protect the sys- tems and programs from further damages.