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In deep exploration, astronomical images are often contaminated by noise when they are transmitted to the earth by satellites. In addition, the existing compression methods are difficult to compress the image with a lower compression sampling ratio, resulting in longer image data transmission time. Donoho proposed a new sampling theory named compressed sensing (CS) in 2006, which can recover a high quality image only using a few information of original image. In this paper, CS method is employed to solve the problem of astronomical image compression, meanwhile, the CS recovery denoising algorithm based curvelet is proposed for astronomical image denoising. The experimental results show that the compression performance of CS method is superior to the famous JPEG and JPEG-2000 compression method, it can compress the high resolution astronomical image with a lower compression sampling ratio. Meanwhile, the proposed algorithm can effectively remove more noise from the noisy image, and preserves more detailed features.

An optical fiber warning system based on vibration sensing is proposed in this paper. This system mainly consists of laser source, common sensor of optical cable and STM32 micro processor, master computer. There are two optical couplers in the sensor optical cable, which makes the structure of fiber optical interferometer. The master computer interface can see the vibration time and signal power clearly.

The issue of missing values (MVs) has been found widely in real-world datasets and obstructed the use of many statistical or machine learning algorithms for data analytics due to their incompetence in processing incomplete datasets. Most of the current MVs imputation methods apply to the datasets with certain specific types or low missing rate. To address this problem, we propose a new method the missing completely at random (MCAR) data with high missing rate. This method is based on generative adversarial networks (GAN) architecture. We execute the training process on discrete dataset with missing values, in order to ensure the generated dataset is completely similar to the feature distribution of original dataset. We conduct our experiments for two different datatypes to prove the feasibility and efficiency of this method. The first one is a public authority dataset with wireless sensors records. The second one is a large group of dataset collected from an industrial production monitoring process. The results compared with traditional missing values imputation methods have shown when the missing rate is higher than 30%, our method performs better in robustness and accuracy.

In this work, we consider a multiuser communication system in fading channels where the transmitter is supplied by hybrid energy sources including power grid and various renewable sources. Specially, the energy harvested from various renewable sources is stored in a limited capacity buffer, and the joint energy incoming is time-varying and possibly unpredictable. In addition, data arrives randomly to the transmitter and queues according to the individual receivers, the wireless channels fluctuate randomly due to fading. Our goal is, under this condition to develop a dynamic power allocation algorithm so as to minimize the time average amount of energy consumed from the power grid over an infinite horizon, subjecting to all data queues stability. The issue is formulated as a stochastic optimization problem and solved by Lyapunov optimization technique which does not require the statistical probabilities of energy harvesting process, data arrivals process and channel state. Simulation results demonstrate that our proposed algorithm provides obviously better performance than other two simple greedy algorithms, meanwhile the algorithm gives a guarantee that the maximum delay of all data queues cannot exceed a given value.

In this paper, we propose an efficient algorithm to decompose a directed acyclic graph (DAG) G into a minimized set of node-disjoint chains, which cover all the nodes of G. For any two nodes u and v on a chain, if u is above v then there is a path from u to v in G. The best algorithm for this problem up to now needs O(n3) time, where n is the number of the nodes of G.

This paper presents an information exchange platform to meet the communication requirements of modern intelligent power distribution and utilization management system. We present the main components, operating principles and application effects of our exchange platform. This platform provides management, configuration, exchanging, monitoring service for communication and running requirements, and designs an agent middleware which communicates and integrates with other systems. Finally, we show how to improve our information exchange platform.

The random time delay brings great challenges to the controller design for the Internet-based teleoperation system, the worst case is that it can destabilize the Internet-based teleoperation system. This paper first gives a brief historical preview of bilateral passive control theory, and then a direct passive scattering transform method, extending the passive bilateral control method to the Internet-based random time delay teleoperation system, is advanced to guarantee the teleoperation system's stability with any non-symmetric random network time delay. Finally, a virtual master-slave manipulator bilateral control scheme is designed for mobile robot teleoperation based on the passive scattering transformation method, and simulations are carried out to verify the results at the end of this paper.

In this paper, we propose an efficient algorithm to decompose a partially ordered set S into a minimum set of chains. It requires only O (k×n2) time and space, where n is the num¬ber of the elements in S and k is the size of a maximum anti¬chain of S.

We consider the following tree-matching problem: Giv¬en labeled, ordered trees P and T, can P be obtained from T by de¬leting nodes? Deleting a node v entails removing all edges incident to v and, if v has a parent u, replacing the edges from u to v by edg¬es from u to the children of v. The best known algorithm for this problem needs O (|T|×|leaves (P) |) time and O (|leaves (P) |×min{DT, |leaves (T) |} + |T| + |P|) space, where leaves (T) (resp. leaves (P) ) stands for the set of the leaves of T (resp. P), and DT (resp. DP) for the height of T (resp. P). In this paper, we present an efficient algo¬rithm that requires O (|T|×|leaves (P) |) time and O (|T| + |P|) space.

To find a new quantitative determination method for low-index ingredients in traditional Chinese medicine, we study the rationality of 5mg/mL casein plate violet circle method using Luo Yu Tong capsule as experimental material. Test results shows: the correlation coefficient R is 0.9989, precision RSD is 2.11%, repeatability (RSD) is 3.66%, the recovery is 98.5%, detection stability is not less than 2h, in the range 20-60U. We can get that: this method transformed content determination into product efficacy determine, have the use value and worth popularizing.

In this paper, the sort, contents and constituent of Hua Xiang Shu Infructescence have been identified, which provide experimental fact for its exploitation. Qualitative research and formation identify have been carried out by chemical test and spectral analysis (UV, IR, MS, 1H-NMR, 13C-NMR), quantitative test is operated by spectrophotometric method. Tannin extract from Hua Xiang Shu Infructescence is hydrolysable tannins, contents is 13.4%, essential components are ellagic acid, gallic acid, 3, 3'-di-O-meltyl ellagic acid and 3,3'-di-O-methyl ellagic acid-4'-O-e-D-gluco-pyranoside. Conclusion: Contents of Tannin from Hua Xiang Shu Infructescence is high, which is seldom found in Chinese crude drug, its components is ellagic acid and other substance, all of them possess important bioactivity, which shows high value to be developed, the last two compounds are firstly separated from Hua Xiang Shu Infructescence.

Y 3−x Ce x Al 5 O 12 (YAG: Ce3+) phosphor particles were prepared by a new method called co-precipitation and low temperature spray pyrolysis (CP-LTSP) with oxalic acid and ammonia as precipitant. It corresponds to the first-step chemical liquid reaction, the second step dehydration and partial decomposition of precipitation droplets at 250°C and then heating at 1100°C or above. Spherical as-prepared particles and agglomerate-free YAG: Ce3+ phosphor particles were obtained respectively. Pure YAG phase could be formed after LTSP at 250°C and then annealing at 1100°C for 4 h. The emission spectra and XRD patterns of YAG: Ce3+ phosphor particles indicated that the optimum doping concentration of Ce3+ was 0.06. The emission intensity increased with the increase of annealing temperature. As a result, the YAG: Ce3+ phosphor particles without optimization annealed at 1550°C for 4 h had the similar emission intensity (96%) of the commercial phosphor by the solid-state method.

Let G(V, E) be a digraph (directed graph) with n nodes and e edges. Digraph G* = (V, E*) is the reflexive, transitive closure if (v, u) ∈ E* iff there is a path from v to u in G. Efficient storage of G* is important for supporting reachability queries which are not only common on graph databases, but also serve as fundamental operations used in many graph algorithms. A lot of strategies have been suggested based on the graph labeling, by which each node is assigned with certain labels such that the reachability of any two nodes through a path can be determined by their labels. Among them are interval labelling, chain decomposition, and 2-hop labeling. However, due to the very large size of many real world graphs, the computational cost and size of labels using existing methods would prove too expensive to be practical. In this paper, we propose a new approach to decompose a graph into a series of spanning trees which may share common edges, to transform a reachability query over a graph into a set of queries over trees. We demonstrate both analytically and empirically the efficiency and effectiveness of our method.

We consider the following tree-matching problem: Given labeled, ordered trees P and T, can P be obtained from T by deleting nodes? Deleting a node v entails removing all edges incident to v and, if v has a parent u, replacing the edges from u to v by edges from u to the children of v. This problem has a lot of applications in the computer engineering, such as XML tree pattern query evaluation, video content-based retrieval, as well as in computational biology, and data mining. The best known algorithm for this problem needs O(|T|Þ|leaves(P)|) time and O(|leaves(P)|Þmin{DT, |leaves(T)|} + |T| + |P|) space, where leaves(T) (resp. leaves(P)) stands for the number of the leaves of T (resp. P), and DT (resp. DP) for the height of T (resp. P). In this paper, we present a new algorithm that requires O(|T|Þmin{DP, |leaves(P)|}) time and O(|T| + |P|) space.

In multi-view video system, variations of different camera setups (for example, camera positions, lighting conditions and camera characteristics) might cause discrepancies on the luminance and chrominance components of different views. From the viewpoint of source compression, this will lead to inaccurate inter-view prediction and lower coding efficiency. In this paper, a histogram-offset-based color correction method is developed for benefitting multi-view video coding. First, disparity estimation is conducted on the rank-transformed domain to identify the maximum matching regions between the reference view and the target view. Within the identified matching regions, the histograms of the reference view and the target view are then calculated, respectively. By using an iterative thresholding approach, a histogram offset is generated and exploited to correct the target view. Experimental results have shown that the proposed color correction method outperforms the histogram matching method on the improvement of coding efficiency.

This paper mainly discusses the controllability and observability property of event-based control system especially to the class of input-affine nonlinear system, which plays an important role in the designing event-based controllers. In this paper, the derivative geometry theory is used to prove the controllability and observability property of event-based control system which hasn't been discussed before. This work enriches the event-based theories and makes a base for the event-based theories to develop in the future. The event-based control theory is now becoming more very valuable in the tele-operation domain because that it can dispose the fixed or uncertain time delay problems. It can also be used in many other domains with good performances. In section I and II, the paper gives a brief review of event-based control system, discusses what the eventbased control system and the model of the event based control system. The rest of the paper mainly discusses the controllability and observability property of event-based control system. A car-like robot is used to show the application of event-based control theory. A simulation result of a triangle-formation keeping using the event-based control theory also presents in this paper.

An XML tree pattern query, represented as a labeled tree, is essentially a complex selection predicate on both structure and content of an XML. Tree pattern matching has been identified as a core operation in querying XML data. However, almost all the proposed algorithms only deal with unordered trees, by which the order of siblings is not considered. In this paper, we discuss a new algorithm for processing ordered tree pattern queries, for which not only the ancestor-descendant and parent-child relationships, but also the order of siblings are significant. The time complexity of the algorithm is bounded by O(|D||Q| + |T|leafQ) and its space overhead is by O(leafTleafQ), where T stands for a document tree, Q for a tree pattern query and D is a largest data stream associated with a query node q of Q, which contains the database nodes that match the node predicate at q. leafT (leafQ) represents the number of the leaf nodes of T (resp. Q). In addition, the algorithm can be adapted to an indexing environment with XB-trees being used. Experiments have been conducted, which shows that the new algorithm is promising.

At low bit-rate video communications, packet loss may easily cause whole-frame loss that, in return, leads to annoying frame drop phenomenon. In this paper, a novel error concealment algorithm is specifically developed for stereoscopic video, called the disparity-based frame difference projection (DFDP), to recover the lost frames at the decoder. The proposed DFDP contains three key components: 1) change detection, 2) disparity estimation, and 3) frame difference projection, which exploits both the intra-view frame difference from one view and interview correlation to estimate the lost frame in another view. The change region computed on the correctly received frame will be used to predict the change region between current missing frame and its previous frame through the estimated disparity, which is the summation of the estimated global disparity and the estimated local disparity. Experimental results have shown that the proposed stereoscopic video error concealment method can effectively restore the lost frames at the decoder and deliver attractive performance, in terms of objective measurement (in peak signal-to-noise ratio) and subjective visual quality.

Debugging design errors is a challenging manual task which requires the analysis of long simulation traces. Trace compaction techniques help engineers analyze the cause of the problem by reducing the length of the trace. This work presents an optimal error trace compaction technique based on incremental SAT. The approach builds a SAT instance from the Iterative Logic Array representation of the circuit and performs a binary search to find the minimum trace length. Since failing properties in the original trace must be maintained in the compacted trace, we enrich our formulation with constraints to guarantee property preservation. Extensive experiments show the effectiveness out SAT based approach as it preserves failing properties with little overhead to the SAT problem while demonstrating on average an order of magnitude in performance improvement.

A graph reachability query, as one of the primary tasks in numerous applications, is to find whether two given data objects, u and v, are related in any way in a large and complex dataset. Formally, the query is about to find if v is reachable from u in a directed graph which is large in size. In this paper, we focus ourselves on building a reachability labeling for large directed graphs, in order to process reachability queries efficiently. A new approach is proposed to compress transitive closure to support reachability checkings. The approach consists of two schemes, called Core-I labeling and Core-II labeling, respectively. For a graph G with n nodes and e edges, the labeling time of Core-I is bounded by O(n + e + t?min{b, s}), where b is the number of the leaf nodes of a spanning tree of G, t is the number of non-tree edges (edges that do not appear in the spanning tree) and s is the number of the start nodes of all non-tree edges in G. The space overhead is bounded by O(n + s?min{b, s}) and the querying time is O(log(min{b, s})). Core-II needs O(n + e + t?min{b, s} + d?s?logmin{b, s}) labeling time and O(n + d?s) space, where d is the number of the end nodes of all non-tree edges in G. But the query time is reduced to O(1). Experiments have been performed, showing that our method is promising.

Given a directed graph G, to check whether a node v is reachable from another node u through a path is often required. In a database system, such an operation is called a recursion computation or reachability checking and not efficiently supported. The reason for this is that the space to store the whole transitive closure of G is prohibitively high. In this paper, we address this issue and propose an 0(n2 + bnradic(b)) time algorithm to decompose a directed acyclic graph (DAG) into a minimized set of disjoint chains to facilitate reachability checking, where n is the number of the nodes and b is the DAG's width, defined to be the size of a largest node subset U of the DAG such that for every pair of nodes u, v isin U, there does not exist a path from u to v or from v to u. Using this algorithm, we are able to label a graph in 0(be) time and store all the labels in O(bn) space with O(logb) reachability checking time, where e is the number of the edges of the DAG. The method can also be extended to handle cyclic directed graphs. Experiments have been performed, showing that our method is promising.