27793638
Wiener Indices of Balanced Binary Trees
We study a new family of trees for computation of the Wiener indices. We introduce general tree transformations and derive formulas for computing the Wiener indices when a tree is modified. We present several algorithms to explore the Wiener indices of our family of trees. The experiments support new conjectures about the Wiener indices.
10659233
Wiener indices of balanced binary trees
We study a new family of trees for computation of the Wiener indices. We introduce general tree transformations and derive formulas for computing the Wiener indices when a tree is modified. We present several algorithms to explore the Wiener indices of our family of trees. The experiments support new conjectures about the Wiener indices.
6971305
Video streaming over multi-hop wireless networks
In this paper, we considered the problem of transporting layered video over erroneous multi-hop wireless networks and proposed a distributed system. Our proposed distributed scheme is comprised of distributed control (DC), distributed buffer (DB) and distributed error control schemes. The DC scheme improves the efficiency of the network bandwidth usage and reduces the end-to-end delay of the streaming application. End-to-end delay jitter can be reduced by proper use of the DB nodes' buffer. Replacing the traditional EEC and ARQ with our distributed FEC and ARQ scheme reduces the error-protection overhead and ARQ delay and improves the wireless channel throughput. A layered video module is developed in GlomoSim 2.03 for video streaming application. We simulated our distributed scheme employing the layered video module in GlomoSim 2.03. Our simulation results confirm that QoS of streaming video over erroneous multi-hop wireless network can be improved using our proposed distributed scheme.
2177063
A New Lightweight and Scalable Encryption Algorithm for Streaming Video over Wireless Networks
A process for improving the stability of a cadmium chalcogenide/copper chalcogenide photovoltaic cell is disclosed. The improvement comprises positioning a layer of a polymer composition containing electrically conductive particles between the copper chalcogenide layer and the metal electrode such that the metal electrode does not make physical contact with the copper chalcogenide layer.
6501389
A Hierarchical Queueing Model for Streaming Video over Multi-Hop Wireless Networks
In our previous work, we proposed a distributed buffer (DB) scheme to tackle the problem of transporting layered video over erroneous multi-hop wireless networks. In DB scheme, some intermediate nodes are selected as DB nodes, which are used to pre-buffer video packets before the video streaming starts. In this paper, a novel hierarchical queueing model for DB nodes is proposed. The video playback quality including buffer overflow probability and video quality throughput can be computed based on the proposed queueing model. The simulation result matches the queueing performance of video streaming application.
17038094
On-line Algorithm for Server Selection of Video Streaming over P2P Networks
Abstract We consider a video streaming application over P2Pnetworks and introduce the P2P on-line server selection problem. This task is related to the classic K-server problem, known from the theory of online algorithms. The difference is that our problem has a dynamic cost matrix, due to network congestion which may trigger the rerouting of streaming paths. With the assumption that the number of hops of any alternative path from the server node p to the requesting node q is at most δ times the number of hops of the shortest path from p to q, our dynamic work function algorithm works for the P2P on-line server selection problem with competitive ratio δ×(2k-1). 1. Introduction In this paper we consider a video streaming application over P2Pnetworks. As we know, it isdifficult to provide large scale streaming service using traditional, centralized client-serverarchitecture, since a bottleneck occurs at the server. The network service model known as Peer-to-Peer (P2P) solves this problem, due to its distributed nature. We address the issue of optimizing the server selection for video streaming in P2P networks.Optimization tasks are classified into online and offline problems. Optimization problems in which the input is received piece by piece and the corresponding piece of output must be produced before knowing the entire input are called online problems. In some optimization tasks, such as job scheduling, both the online and offline versions of the problem are meaningful. Many other situations, such as telephone circuit switching, investment planning etc. are intrinsically online. For these problems, offline algorithms are not acceptable. Competitive algorithms were introduced by Sleator and Tarjan [1] in the context of optimization problems. They sought a worst case complexity measure for on-line algorithms that have to make decisions based on current and previous parts of the input. In the on-line problem the input is given as a sequence σ = σ
21956342
Architectural design and implementation of highly available and scalable medical system with IBM Websphere middleware
Medical systems require the end-to-end high availability and scalability. There are many components in a medical system, and each individual component contributes to the overall system availability and scalability. We present the formulas to assess the overall system availability and capacity planning, and we architect approaches and technologies to make all components highly available in all tiers by clustering, workload management, and replication. We discuss how to unify all medical systems and design the uniform framework for different kinds of medical systems to hook up with this framework so that we can maintain a highly available and highly scalable system with ease. We use the n-tier distributed component based architecture and J2EE technologies as well as Web services to interact with .NET and others. We discuss how to program in the framework for high availability and scalability and how to upgrade application software without service interruption to achieve continuous availability. We show how to add or reduce hardware capacity in each tier and how to maintain hardware and software without service interruption as well as how to balance the capacity and availability among tiers.
40601169
Performance Modeling and Practical Parallel Algorithms of Cluster Computing with Applications on Distributed Platforms
27202859
Affective interaction based on person-independent facial expression space
This paper proposes a person-independent facial expression space (PIFES) to analyze and synthesize facial expressions based on supervised locality preserving projections (SLPP), which aligns different subjects and different intensities of facial expressions on one generalized expression manifold. Interactive curves of different patterns are generated according to the input facial expression image sequence, and target responsive expression images are synthesized for different emotions. In order to synthesize arbitrary expressions for a new person with natural details, a novel approach based on local geometry preserving between the input face image and the target expression image is proposed. Experimental results clearly demonstrate the efficiency of the proposed algorithm.
45158244
Discovering pattern-based subspace clusters by pattern tree
Traditional clustering models based on distance similarity are not always effective in capturing correlation among data objects, while pattern-based clustering can do well in identifying correlation hidden among data objects. However, the state-of-the-art pattern-based clustering methods are inefficient and provide no metric to measure the clustering quality. This paper presents a new pattern-based subspace clustering method, which can tackle the problems mentioned above. Observing the analogy between mining frequent itemsets and discovering subspace clusters, we apply pattern tree - a structure used in frequent itemsets mining to determining the target subspaces by scanning the database once, which can be done efficiently in large datasets. Furthermore, we introduce a general clustering quality evaluation model to guide the identifying of meaningful clusters. The proposed new method enables the users to set flexibly proper quality-control parameters to meet different needs. Experimental results on synthetic and real datasets show that our method outperforms the existing methods in both efficiency and effectiveness.
14158906
A New Certified Email Protocol
As a continuative effort of our WICS'05 paper, a new certified Email protocol is proposed. Email is a standard communication method nowadays but certified email is poorly developed and has very limited application. A certified email protocol assures non-repudiability which means that if the email is successfully sent, the sender cannot deny s/he has actually sent the mail and the recipient cannot deny s/he has actually received it. Our protocol uses an efficient RSA-based convertible signature with non- interactive partial signature proof method and additively split signing secret key.