1532971
Relative Generic Computational Forensic Techniques
Computational forensic engineering is the process of identification of the tool or algorithm that was used to produce a particular output or solution by examining the structural properties of the output. We introduce a new Relative Generic Forensic Engineering (RGFE) technique that has several advantages over the previously proposed approaches. The new RGFE technique not only performs more accurate identification of the tool used but also provides the identification with a level of confidence. Additionally, we introduce a generic formulation (integer linear programming formulation) which enables rapid application of the RGFE approach to a variety of problems that can be formulated as 0-1 integer linear programs. 
 
The key innovations of the RGFE technique include the development of a simulated annealing-based (SA) CART classification technique and a generic property formulation technique that facilitates property reuse. We introduce instance properties which enable an enhanced classification of problem instances leading to a higher accuracy of algorithm identification. Finally, the single most important innovation, property calibration, interprets the value for a given algorithm for a given property relative to the values for other algorithms. We demonstrated the effectiveness of the RGFE technique on the boolean satisfiability (SAT) and graph coloring (GC) problems.
1973000
Gateway placement for latency and energy efficient data aggregation [wireless sensor networks]
We propose the use of multiple gateways to significantly reduce latency and energy consumption in multi-hop wireless sensor networks during data aggregation. We have derived efficient integer linear programming formulations as well as a novel negative selection statistically-tuned heuristics. The heuristics are based on newly developed relaxation based lower bounds that are also used to quantify the effectiveness of the proposed heuristics. Our simulation study indicates that the use of gateways can often reduce latency and energy consumption by several times.
18507162
A statistical methodology for wire-length prediction
In this paper, the classic wire-length estimation problem is addressed and a new statistical wire-length estimation approach that captures the probability distribution function of net lengths after placement and before routing is proposed. These types of models are highly instrumental in formalizing a complete and consistent probabilistic approach to design automation and design closure where, along with optimizing the pertinent cost function, the associated prediction error is also considered. The wire-length prediction model was developed using a combination of parametric and nonparametric statistical techniques. The model predicts not only the length of the net using input parameters extracted from the floorplan of a design, but also probability distributions that a net with given characteristics after placement will have a particular length. The model is validated using the learn-and-test and resubstitution techniques. The model can be used for a variety of purposes, including the generation of a large number of statistically sound, and therefore realistic, instances of designs. The net models were applied to the probabilistic buffer-insertion problem and substantial improvement was obtained in net delay after routing (~ 20%) when compared to a traditional bounding box (BBOX)-based buffer-insertion strategy
6612620
Design techniques for sensor appliances: foundations and light compass case study
We propose the first systematic, sensor-centric approach for quantitative design of sensor network appliances. We demonstrate its use by designing light appliance devices and the associated middleware. We have developed five models which are required to make this problem tractable and to undertake the challenging task of designing light sensor appliances: i. physical world, ii. light sensor, iii. physical phenomenon, iv. appliance design, and v. computational model. With these models in place, we present the new design methodology that consists of two main steps: 1. a procedure for placement of individual sensors of the appliances, and 2. error minimization-based sensor data interpretation middleware. We have developed new optimization techniques for both tasks. A portable light sensor system was designed using the optimization intensive procedure, and its effectiveness demonstrated.
2985827
Flexible ASIC: shared masking for multiple media processors
ASIC provides more than an order of magnitude advantage in terms of density, speed, and power requirement per gate. However, economic (cost of masks) and technological (deep micron manufacturability) trends favor FPGA as an implementation platform. In order to combine the advantages of both platforms and alleviate their disadvantages, recently a number of approaches, such as structured ASIC/regular fabrics, have been proposed. Our goal is to introduce an approach that has the same objective, but is orthogonal to those already proposed. The idea is to implement several ASIC designs in such a way that they share the datapath, memory structure, and several bottom layers of interconnect, while each design has only a few unique metal layers. We identified and addressed two main problems in our quest to develop a CAD flow for realization of such designs. They are: (i) the creation of the datapath, and (ii) the identification of common and unique interconnect for each design. Both problems are solved optimally using ILP formulations. We assembled a design flow platform using two new programs and the Trimaran and Shade tools. We quantitatively analyzed the advantages and disadvantages of the approach using the Mediabench benchmark suite.
926253
Power minimization in QoS sensitive systems
The majority of modern multimedia and mobile systems have two common denominators: quality-of-service (QoS) requirements, such as latency and synchronization, and strict energy constraints. However, until now no synthesis techniques have been proposed for the design and efficient use of such systems. We have two main objectives: conceptual and synthesis. The conceptual objective is to develop a generic practical technique for the automatic development of online adaptive algorithms from efficient off-line algorithms using statistical techniques. The synthesis objective is to introduce the first design technique for QoS low-power synthesis. We introduce a system of provably-optimal techniques that minimize energy consumption of stream-oriented applications under two main QoS metrics: latency and synchronization. Specifically, we study how multiple voltages can be used to simultaneously satisfy hardware constraints and minimize power consumption while preserving the requested level of QoS. The purpose of the off-line algorithm is threefold. First, it is used as input to statistical software which is used to identify important and relevant parameters of the processes. Second, the algorithm provides buffer occupancy rate indicators. Lastly, it provides a way to combine buffer occupancy and QoS metrics to form a fast and efficient online algorithm. The effectiveness of the algorithms is demonstrated on a number of standard multimedia benchmarks.
2757003
Autonomic Resource Management for a Cluster that Executes Batch Jobs
Dynamic resource allocation in a server cluster has received much attention in recent years. We have developed heuristic algorithms for autonomic server provisioning for a cluster that executes batch jobs. These jobs have a common, or shared, completion deadline. External factors that may affect the decision to allocate servers are modeled as a time-varying cost function. The provisioning goal is to ensure that all jobs are completed on time while minimizing the total cost of server usage. Two heuristic algorithms which adapt to changing workload are presented. The merit of these algorithms is evaluated by simulation. Our results show that the proposed algorithms can successfully use fewer servers during the high cost period while ensuring that all jobs meet their deadline. They also perform far better than static server allocation
35883623
Supporting organizational knowledge management with agents
Organizations are looking at ways to manage their information resources. Both the capture and the use of data created by the organization have come under scrutiny. Part of the concern comes from their desire to enhance the business process and part comes from the explosion of data available to any organization. In this context, the role of committees is being examined both as consumers and producers of information. The present work is focused on making the vast amount of unstructured text more useful to committees. An agent environment has been designed and implemented.
8229875
A Reputation-based Trust Management in Peer-to-Peer Network Systems
Peer-to-peer networks have gained a lot of attention over the last couple of years, mainly due to the popularity of the free multimedia file-sharing program Napster and a legal battle around it. Being open by nature P2P systems represent an ideal environment for various types of malicious intrusions. The problem of securing hosts on P2P network while keeping the openness of the system has been studied extensively over last couple of years but still remains open. Existing solutions based on reputation management either employ centralized algorithms or rely on peers' cooperation on the network. We describe a fully decentralized approach that allows computing peers' reputation based on the traffic between a node and its peers, independently of these peers willingness to cooperate in calculation of their reputation. 1 INTRODUCTION Peer-to-peer (P2P) network systems are increasingly gaining popularity on the Internet. These networks allow individual hosts (peers) to share and distribute various types of information over the Internet. By their nature, P2P networks are structured in a way that allows an open and unsupervised communication between peers. Therefore, these systems are vulnerable to various types of attacks, among which are denial-of-service attacks (DoS) and distribution of viruses. To protect themselves from malicious intentions, hosts should be able to identify reliable peers for communication. Identifying these peers is a challenging task in highly dynamic network environments like P2P networks. In this paper we suggest a solution to this problem based on the notion of trust. We propose a policy for managing traffic in peer-to-peer network based on peers' reputation. We also describe a model for computing this reputation using the trust score based on the peers' interaction with each other. Unlike most existing reputation-based models, our approach does not employ a centralized storage and only produces reputation scores on demand. The proposed solution is fully distributed and does not require any cooperation from the rest of the network. Our model aims to help users to select the most reliable peers whose past behavior shows willingness to participate in a proper functioning of the P2P system and at the same time to anticipate possible attacks from malicious peers by limiting their access to the victim peer's resources. In this paper we focus on a particular type of P2P systems, called Gnutella, which proved to be one of the most popular P2P systems. Furthermore, unlike other popular P2P applications such as KaZaa, the source …
8573370
Core selection with end-to-end QoS support
Core-based routing with Quality of Service (QoS) support is essential to facilitate multi-sender multimedia multicast applications such as video conferencing and virtual collaboration applications. In this paper, we introduce (i) a new application-level service class framework that allows group members to easily indicate their desired service quality and (ii) the use of as many cores per group as necessary in corebased routing to maximize the number of group members with satisfied QoS requirements. Under the service class framework, we formulate the novel core selection problem that selects as many cores as necessary while maximizing the number of satisfied group members. We propose a new core selection algorithm to address the problem and provide a complete core selection protocol using the algorithm. Experimental results show that our core selection algorithm performs as well as the optimal algorithm and significantly outperforms a recent core selection algorithm with QoS support using a single core.
29262099
Transaction models for design environments
Abstract Design data bases used in the design of engineering artifacts have characteristics quite different from conventional data bases. While conventional data bases have, at any given time, a single correct value for each of object, design data bases, due to the presence of design alternates or versions, have available several correct versions of design objects. However, during a design process, when several design objects are involved, the different versions of each object chosen for the design has to be controlled such that they are compatible or version consistent. This article formalizes the notion of version consistency and proposes two transaction models for design processes, where the notion of version consistency itself is used as a basis for scheduling design transactions. A mechanism for enforcing version control is also presented.