- Zhenhua Li;Yun Zhang;Yunhao Liu;
If every programmer of cloud-hosted apps possessed exceptional technical capability and endless patience, the Dev Ops environment(also known as Platform-as-a-Service, or Paa S) would perhaps become irrelevant. However, the reality is almost always the opposite case. Hence, IT engineers dream of a reliable and usable Dev Ops environment that can substantially facilitate their developments and simplify their operations.Current Dev Ops environments include Google App Engine, Docker, Kubernetes, Mesos, and so forth. In other words, Paa S bridges the gap between vivid IT engineers and stiff cloud systems. In this paper, we comprehensively examine state-of-the-art Paa S solutions across various tiers of the cloud-computing Dev Ops stack. On this basis,we identify areas of consensus and diversity in their philosophies and methodologies. In addition, we explore cutting-edge solutions towards realizing a more fine-grained, full-stack Dev Ops environment. From this paper,readers are expected to quickly grasp the essence, current status, and future prospects of Paa S.
2017年01期 v.22 1-9页 [查看摘要][在线阅读][下载 673K] [下载次数：145 ] |[网刊下载次数：0 ] |[引用频次：21 ] |[阅读次数：85 ] - Xiao Sun;Yueting Chai;Yi Liu;Jianping Shen;Yadong Huang;
In the last decade, as an emerging transaction measure driven by computer and internet technology,e-commerce experienced explosive growth in many areas. It has greatly broken down the limitations of space and time to economic activities, thus changing the rules of business fundamentally. Significant work has been done to understand the laws of e-commerce from multiple dimensions, but the question of how e-commerce shapes firms' specialization and market structure from the perspective of spatial factors remains obscure. In this paper, we propose a simple and symmetric firm resource allocation model with a specialized-economy production function and market size constraint, to investigate how individual firms adjust resource allocation with reachable transaction scope expanded. It is shown that with the expansion of reachable transaction scope, individual firms discretely take back one unit resource from a low-investment direction and, instead, channel it to a "specialized direction".Meanwhile, at the macro level, an optimal division network evolves from a static self-sufficient stage to a diverse semi-specialized stage, and finally to a highly integrated completely specialized stage. Ergo, a Complex Adaptive System(CAS) based simulation framework is constructed. Designed simulation experiments are carried out and confirm to the analysis result of our proposed model.
2017年01期 v.22 10-28页 [查看摘要][在线阅读][下载 924K] [下载次数：49 ] |[网刊下载次数：0 ] |[引用频次：5 ] |[阅读次数：115 ] - Kuangyu Liu;Xiangming Xi;Zhiming Xu;Shuning Wang;
In order to recover a signal from its compressive measurements, the compressed sensing theory seeks the sparsest signal that agrees with the measurements, which is actually an l_0 norm minimization problem. In this paper, we equivalently transform the l_0 norm minimization into a concave continuous piecewise linear programming,and propose an optimization algorithm based on a modified interior point method. Numerical experiments demonstrate that our algorithm improves the sufficient number of measurements, relaxes the restrictions of the sensing matrix to some extent, and performs robustly in the noisy scenarios.
2017年01期 v.22 29-41页 [查看摘要][在线阅读][下载 330K] [下载次数：39 ] |[网刊下载次数：0 ] |[引用频次：1 ] |[阅读次数：92 ] - Xiaoqing Peng;Xiaodong Yan;Jianxin Wang;
Proteins interact with each other to form protein complexes, and cell functionality depends on both protein interactions and these complexes. Based on the assumption that protein complexes are highly connected and correspond to the dense regions in Protein-protein Interaction Networks(PINs), many methods have been proposed to identify the dense regions in PINs. Because protein complexes may be formed by proteins with similar properties,such as topological and functional properties, in this paper, we propose a protein complex identification framework(KCluster). In KCluster, a PIN is divided into K subnetworks using a K-means algorithm, and each subnetwork comprises proteins of similar degrees. We adopt a strategy based on the expected number of common neighbors to detect the protein complexes in each subnetwork. Moreover, we identify the protein complexes spanning two subnetworks by combining closely linked protein complexes from different subnetworks. Finally, we refine the predicted protein complexes using protein subcellular localization information. We apply KCluster and nine existing methods to identify protein complexes from a highly reliable yeast PIN. The results show that KCluster achieves higher Sn and Sp values and f-measures than other nine methods. Furthermore, the number of perfect matches predicted by KCluster is significantly higher than that of other nine methods.
2017年01期 v.22 42-51页 [查看摘要][在线阅读][下载 599K] [下载次数：31 ] |[网刊下载次数：0 ] |[引用频次：3 ] |[阅读次数：84 ] - Bofei Xia;Yushun Fan;Cheng Wu;Bing Bai;Junqi Zhang;
An increasing number of web services are being invoked by users to create user applications(e.g.,mashups). However, over time, a few good services in service systems have become deprecated, i.e., the service is initially available and is invoked by service users, but later becomes unavailable. Therefore, the prediction of service deprecation has become a key issue in creating reliable long-term user applications. Most existing research has overlooked service deprecation in service systems and has failed to consider long-term service reliability when making service recommendations. In this paper, we propose a method for predicting service deprecation, which comprises two components: Service Comprehensive Feature Modeling(SCFM) for extracting service features relevant to service deprecation and Deprecated Service Prediction(DSP) for building a service deprecation prediction model. Our experimental results on a real-world dataset demonstrate that our method yields an improved Area-Under-the-Curve(AUC) value over existing methods and thus has better accuracy in service deprecation prediction.
2017年01期 v.22 52-61页 [查看摘要][在线阅读][下载 374K] [下载次数：38 ] |[网刊下载次数：0 ] |[引用频次：4 ] |[阅读次数：51 ] - Xiaoxin Fu;Yongheng Jiang;Dexian Huang;Kaisheng Huang;Jingchun Wang;
This paper proposes an approach based on Ordinal Optimization(OO) to solve trajectory planning for automated driving. As most planning approaches based on candidate curves optimize the trajectory curve and the velocity profile separately, this paper formulates the problem as an unified Non-Linear Programming(NLP) model,optimizing the trajectory curve and the acceleration profile(acceleration is the derivative of velocity) simultaneously.Then a hybrid optimization algorithm named OODE, developed by combining the idea of OO and Differential Evolution(DE), is proposed to solve the NLP model. With the acceleration profile optimized "roughly", OODE computes and compares "rough"(biased but computationally-easier) curve evaluations to select the best curve from candidates, so that a good enough curve can be obtained very efficiently. Then the acceleration profile is optimized again "accurately" with the selected curve. Simulation results show that good enough solutions are ensured with a high probability and our method is capable of working in real time.
2017年01期 v.22 62-72页 [查看摘要][在线阅读][下载 446K] [下载次数：67 ] |[网刊下载次数：0 ] |[引用频次：3 ] |[阅读次数：46 ] - Yu Bai;Zhiming Xu;Xiangming Xi;Shuning Wang;
This paper works on a modified simplex algorithm for the local optimization of Continuous Piece Wise Linear(CPWL) programming with generalization of hinging hyperplane objective and linear constraints. CPWL programming is popular since it can be equivalently transformed into difference of convex functions programming or concave optimization. Inspired by the concavity of the concave CPWL functions, we propose an Objective Variation Simplex Algorithm(OVSA), which is able to find a local optimum in a reasonable time. Computational results are presented for further insights into the performance of the OVSA compared with two other algorithms on random test problems.
2017年01期 v.22 73-82页 [查看摘要][在线阅读][下载 667K] [下载次数：56 ] |[网刊下载次数：0 ] |[引用频次：0 ] |[阅读次数：83 ] - Xi Ma;Fuchun Sun;Hongbo Li;Bing He;
In this paper, the attitude control problem of rigid body is addressed with considering inertia uncertainty,bounded time-varying disturbances, angular velocity-free measurement, and unknown non-symmetric saturation input. Using a mathematical transformation, the effects of bounded time-varying disturbances, uncertain inertia,and saturation input are combined as total disturbances. A novel finite-time observer is designed to estimate the unknown angular velocity and the total disturbances. For attitude control, an observer-based sliding-mode control protocol is proposed to force the system state convergence to the desired sliding-mode surface; the finite-time stability is guaranteed via Lyapunov theory analysis. Finally, a numerical simulation is presented to illustrate the effective performance of the proposed sliding-mode control protocol.
2017年01期 v.22 83-91页 [查看摘要][在线阅读][下载 805K] [下载次数：34 ] |[网刊下载次数：0 ] |[引用频次：4 ] |[阅读次数：67 ] - Baihong Lin;Yukui Pei;Liuguo Yin;Jianhua Lu;
The design of a high-speed decoder using traditional partly parallel architecture for Non-Quasi-Cyclic(NQC) Low-Density Parity-Check(LDPC) codes is a challenging problem due to its high memory-block cost and low hardware utilization efficiency. In this paper, we present efficient hardware implementation schemes for NQCLDPC codes. First, we propose an implementation-oriented construction scheme for NQC-LDPC codes to avoid memory-access conflict in the partly parallel decoder. Then, we propose a Modified Overlapped Message-Passing(MOMP) algorithm for the hardware implementation of NQC-LDPC codes. This algorithm doubles the hardware utilization efficiency and supports a higher degree of parallelism than that used in the Overlapped Message Passing(OMP) technique proposed in previous works. We also present single-core and multi-core decoder architectures in the proposed MOMP algorithm to reduce memory cost and improve circuit efficiency. Moreover, we introduce a technique called the cycle bus to further reduce the number of block RAMs in multi-core decoders. Using numerical examples, we show that, for a rate-2/3, length-15360 NQC-LDPC code with 8.43-d B coding gain for Binary PhaseShift Keying(BPSK) in an Additive White Gaussian Noise(AWGN) channel, the decoder with the proposed scheme achieves a 23.8%–52.6% reduction in logic utilization per Mbps and a 29.0%–90.0% reduction in message-memory bits per Mbps.
2017年01期 v.22 92-103页 [查看摘要][在线阅读][下载 755K] [下载次数：27 ] |[网刊下载次数：0 ] |[引用频次：8 ] |[阅读次数：46 ] - Jian Pan;Jun Tang;Wei Zhu;
Sparse signal recovery problems are common in parameter estimation, image processing, pattern recognition, and so on. The problem of recovering a sparse signal representation from a signal dictionary might be classified as a linear constraint l_0-quasinorm minimization problem, which is thought to be a Non-deterministic Polynomial-time(NP)-hard problem. Although several approximation methods have been developed to solve this problem via convex relaxation, researchers find the nonconvex methods to be more efficient in solving sparse recovery problems than convex methods. In this paper a nonconvex Exponential Metric Approximation(EMA)method is proposed to solve the sparse signal recovery problem. Our proposed EMA method aims to minimize a nonconvex negative exponential metric function to attain the sparse approximation and, with proper transformation,solve the problem via Difference Convex(DC) programming. Numerical simulations show that exponential metric function approximation yields better sparse recovery performance than other methods, and our proposed EMA-DC method is an efficient way to recover the sparse signals that are buried in noise.
2017年01期 v.22 104-111页 [查看摘要][在线阅读][下载 703K] [下载次数：30 ] |[网刊下载次数：0 ] |[引用频次：0 ] |[阅读次数：40 ] - Yizhou Fan;Ding Ni;Hongbing Ma;
Hyperspectral remote sensing is becoming more and more important amongst remote sensing techniques. In this paper, we present a hyperspectral database(Hyper DB) designed to cooperate with an embedded hyperspectral image processing system developed by the authors. Hyperspectral data are recognized and categorized by their land coverage class and band information, and can be imported from various sources such as airborne and spaceborne sensors carried by airplanes or satellites, as well as handhold instruments based on in situ ground observations. Spectral library files can be easily stored, indexed, viewed, and exported. Since Hyper DB follows standard design principles—independence, data safety, and compatibility—it satisfies the practical demand for managing categorized hyperspectral data, and can be readily expanded to other peripheral applications.
2017年01期 v.22 112-118页 [查看摘要][在线阅读][下载 559K] [下载次数：53 ] |[网刊下载次数：0 ] |[引用频次：2 ] |[阅读次数：46 ]