Dianxi Shi

• Wuhan University

Server consolidation is one of the critical techniques for energy-efficiency in cloud data centers. As it is often assumed that cloud service instances (e.g., Amazon EC2 instances) utilize the shared storage only, most existing work did not consider the problems introduced by utilizing local storage. In recent years, however, cloud service provider...

With the development of wireless sensor network (WSN) technologies, WSNs have been applied in many areas. In all WSN technologies, localization is a crucial problem. Traditional localization approaches in WSNs mainly focus on calculating the current location of sensor nodes or mobile objects. In this paper, we study the problem of future location p...

Hyperlink Induced Topic Search (HITS) is the most authoritative and most widely used personalized ranking algorithm on networks. The HITS algorithm ranks nodes on networks according to power iteration, and has high complexity of computation. This paper models the HITS algorithm with the Monte Carlo method, and proposes Monte Carlo based algorithms...

Providing optimal Quality of Service (QoS) for Cloud Services Delivery Networks (CSDN) is a challenging task due to the mutual-interference phenomenon among multiple applications. Existing approaches only provide best-effort services, which aim to maximize the number of served users and sacrifice service dependability. To enhance the service depend...

Different from traditional social networks, the location-based social networks allow people to share their locations according to location-tagged user-generated contents, such as checkins, trajectories, text, photos, etc. In location-based social networks, which are based on users' checkins, people could share his or her location according to check...

Context situation, which means a snapshot of the status of the real world, is formed by integrating a large amount of contexts collected from various resources. How to get the context situation and use the situation to provide better services is a challenging issue. In this paper, we focused on this challenge on the basis of the mobile cloud comput...

Cloud computing has been attracting more and more enterprises and researchers, and one goal of it is that computing is provided on demand as a service like water and electricity. Meanwhile, data-intensive service like MapReduce jobs is widely used in data centers. We model the data-intensive service system as an M/M(t)/n/k queueing system, where th...

Web entities are often associated with many attributes that describe them. It is essential to extract these attributes for Web entity data extraction. This paper proposes a novel approach using duplicated attribute value pairs. We start by constructing a initial seed set of attributes including names and enumerable values, and a training set of Web...

Mining of repeated patterns from HTML documents is the key step towards Web-based data mining and knowledge extraction. Many web crawling applications need efficient repeated patterns mining techniques to generate their wrapper automatically. Existing approaches such as tree matching and string matching can detect repeated patterns with high precis...

Mining repeated patterns from HTML documents is a key step for typical applications of Web information extraction, which require efficient techniques of patterns mining to generate wrappers automatically. Existing approaches such as tree matching and string matching can detect repeated patterns with a high precision, but their efficiency is still a...

Extracting fault features with the error logs of fault injection tests has been widely studied in the area of large scale distributed systems for decades. However, the process of extracting features is severely affected by a large amount of noisy logs. While the existing work tries to solve the problem by compressing logs in temporal and spatial vi...

Many challenges in multi-agent coordination can be modeled as Distributed Constraint Optimization Problems (DCOPs). Aiming at DCOPs with low constraint density, this paper proposes a distributed algorithm based on the idea of greed and backjumping. In this algorithm, each agent makes decisions according to the greedy principle that the most assignm...

Open Source Software (OSS) evaluation uses various metrics to compute the scores or levels of OSS. However the metrics used in existing evaluation models are difficult to rate and costly to obtain, and the rates of metrics are often tendentiously subjective and inconvincible. This paper tries to find some kinds of data in OSS repositories which can...

Mining log pattern to analyze the faults in large scale distributed system is affected by the existence of redundant and ambiguous noisy error logs. While existing works try to compress logs in a coarse granularity from temporal and spatial view to remove the redundancy, they fail to reserve those ambiguous logs that might truly relate to a fault,...

Participants of a software project have a significant impact on whether the project could achieve success, and the relevant information can reflect some trustworthy properties of software. By studying a large number of OSS projects in SourceForge, the role configuration of these projects is analyzed, and some latent frequent patterns are discovered...

In a typical large-scale data center, a set of applications are hosted over virtual machines (VMs) running on a large number of physical machines (PMs). Such a virtualization technique can be used for conserving power consumption by minimizing the number of PMs that should be turned on according to the application requirements to resource. However,...

In the open and dynamic pervasive computing environment, it is challenging to detect and handle the frequently occurred failures of service request. The widely used transparent mechanisms Remote Procedure Call and Object Request Broker have a great impact on the adaptive fault-tolerance, because they make it difficult for service requester to sense...

Most of metrics used in existing OSS evaluation models are difficult to rate and costly to obtain, and the rates of them are tendentiously subjective and inconvincible. This paper tries to find some kinds of data in OSS repositories which can be easily obtained and used as metrics for more practical OSS evaluation. By mining and analyzing nearly 8,...

With the appearance and growing application of open systems such as Internet, delegation is a primary mechanism to enforce access control in such systems. This paper distinguishes two kinds of delegation: authority delegation (AUD) and access delegation (ACD), and proposes a first-order logic system SRDL to capture the features of the two kinds of...

Trust management systems enable decentralized authorization by searching distributed credentials from network. We argue that such distributed searching processes may encounter many technical or non-technical problems, and can be avoided by storing delegation credentials redundantly with acceptable costs. We propose a scoped-role based trust managem...

Although a large number of consensus and atomic broadcast algorithms based on failure detectors have been published during the years, they are still criticized for poor performance in terms of communication latency. To reduce the latency, some algorithms based on optimistic assumptions have been proposed. When the optimistic assumption holds, these...

Atomic Broadcast is a fundamental building block in the construction of fault tolerant distributed applications. Although a number of algorithms have been published, the implementation of such a primitive is still considered costly in terms of communication latency. To solve this problem, some algorithms based on optimistic assumptions are proposed...

Traditional middleware technology is confronted with great challenges in open and dynamic pervasive computing environments. The infrastructure of a pervasive middleware, which refers to the substrate of communal pervasive facilities, should be highly interoperable, scalable and QoS-enabled as well as provide necessary mechanisms to support pervasiv...

The increasing cost of owning and managing IT systems is leading to outsourcing commercial online services to service hosting utility centers by means of service level agreements (SLAs). Low resource utilization and partial service overload are two main issues in utility centers operation. The paper describes a SLA-based fine-grained resource donat...

The paper proposes a resource framework COROB for overload handling in component application hosting center through dynamic resource borrowing among hosted applications. The main idea is to utilize the fine-grained idle server resource of other applications to partake of surging workload, while keeping the resource borrowing under control for not v...

To study MRI appearances of painful ophthalmoplegia syndrome and provide image basis for clinical diagnosis of painful ophthalmoplegia syndrome. Seventeen cases with painful ophthalmoplegia syndrome diagnosed clinically were collected. MRI ordinary scan and gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) contrast fatty-restraint scan were...

To investigat the association of HLA-DRB1 alleles and the susceptibility to alveolar echinococcosis (AE). Thirty-five patients with AE in the high prevalence areas in the west of China were investigated for HLA-DRB1 gene by PCR/SSP technique. The results were compared with 104 normal healthy peoples. Frequency of HLA-DRB1 * 040x was 26% in patient...

To discuss B-ultrasonography, CT and MRI appearances and image diagnostic value for ocular cysticercosis. In the 29 cases with ocular cysticercosis, 21 cases were examined by B-ultrasonography, 19 cases by X-ray computed tomography (CT) and 6 cases by magnetic resonance imaging (MRI). At the living stage of the cysticercus, B-ultrasound might detec...

Downton's bivariate exponential distribution, a special case of Kibble's bivariate gamma distribution, has an important application in lifetime analysis (Downton, 1970). In the present paper, the explicit formulae for the elements of Fisher information matrix for this distribution are derived. Numerical values for these elements were also obtained...

Delegation is essential to the flexibility and scalability of trust management systems. But unrestricted delegation may result in privilege proliferation and breach the privacy of information systems. The delegation models of existing trust management systems can not avoid privilege transition, and being lack of effective constraints on delegation...