206754645
Statistical performance guarantees in large-scale cross-path packet switch
In this paper, we develop a general framework for a novel switch architecture, the cross-path switch, to provide persession statistical quality of service (QoS) guarantees. With characterizing the service each session receives by service curves, we derive a set of statistical bounds on the delay, backlog, and departure processes at the switch on a per-session manner using exponential bounded burstiness processes as source session traffic models. These bounds show that the service guarantees offered by the cross-path switch depend on the way of token assignment in the central stage of the switch. To provide better performance guarantees,we determine the criteria for designing a token assignment algorithm for the cross-path switch. Also, we quantify the service guaranteed by the cross-path switch with the central stage implemented in optical domain, which is important for the provision of QoS guarantees to each session in semioptical networks.
40366616
Parallel routing algorithms in Benes-Clos networks
A new parallel algorithm for route assignment in Benes-Clos network is studied. In packet switching systems, switch fabrics must be able to provide internally conflict-free paths simultaneously and to accommodate packets requesting for connections in real-time as they arrive at the inputs. Most known sequential route assignment algorithms, such as the looping algorithm for Benes (1962) networks or Clos (1953) networks, are designed for circuit switching systems where the switching configuration can be rearranged at a relatively low speed. Most existing parallel routing algorithms are not practical for packet switching because they either assume the set of connection requests is a full permutation or fail to deal with output contentions among the set of input packets. We develop a parallel routing algorithm by solving a set of Boolean equations which are derived from the connection requests and the symmetric structure of the Benes network. Our approach can handle both the partial permutations and the output contention problem easily. The time complexity of our algorithm is O(log/sup 2/N), where N is the network size. Furthermore, we extend the algorithm and show that it can be applied to the Clos network if the number of central modules is a power of two.
51888770
Statistical performance guarantees in large-scale cross-path packet switch
Recently, a quasi-static routing scheme called path switching was proposed for large-scale packet switch systems. The path-switched Clos network is called a cross-path switch. The cross-path switch is capable of supporting multirate and multicast traffic. In this paper, we develop a general framework for it to handle multimedia traffic. We study the statistical behavior of the cross-path switch using exponential bounded burstiness (EBB) processes as source session traffic models. With characterizing the service guarantees by service curves, we derive a set of statistical bounds on the delay, backlog and departure processes at the switch on a per-session basis. These bounds are necessary for providing per-session statistical quality of service (QoS) guarantees in the cross-path switch and achieving high system utilization.
10214085
Influence of promoter potency on the transcriptional effects of YY1, SRF and Msx-1 in transient transfection analysis
Potent viral promoters/enhancers are often used to achieve high level expression of ectopic genes in transient transfection analysis. By using a GAL4-responsive transcription assay system, we show that the use of potent eukaryotic expression vectors can lead to biased transcriptional effects. Three functionally diverse transcription factors, YY1, SRF and Msx-1, were examined and each was found to exhibit a strong transrepression function in the context of the DNA binding domain of GAL4 when expressed from the cytomegalovirus (pCMV) or simian virus 40 (pSV) promoters/enhancers. An internal 15 amino acid domain of YY1 mediating transrepression in the viral promoter setting was identified. This GAL4-mediated transcriptional repression could, however, be completely relieved by using the yeast alcohol dehydrogenase promoter (pADH) to drive gene expression, which is approximately 100-fold weaker than canonical pCMV and pSV in cultured mammalian cells. In addition, low level expression achieved with the pADH vector unveiled the intrinsic transactivation functions of YY1 and SRF previously not observed with the GAL4 assay system. Our results highlight a potential pitfall in conventional pCMV- and pSV-based transfection assays and suggest that the use of a low level expression system may be preferable in most transcriptional analysis.
16028378
Improving the Performance of Infomax Using Statistical Signal Processing Techniques
In this paper, we present a new method that speeds up the convergence of the infomax algorithm proposed by Bell and Sejnowski. One effect of the infomax algorithm is that the 2nd order and 4th order statistical correlations are reintroduced to the signals during the learning process due to the optimization with respect to the complete signal statistics. We show that repetitively forcing 2nd and 4th order correlations to zero speeds up the convergence and improves separating sources with fewer data points.
7135959
On original generation of structure in legal documents
This position paper advocates a vision in the development of automated legal reasoning and presents evidence supporting the plausibility of that vision. The paper observes that original creation of documents of legal import in either fully formal or semistructured form offers the prospect of greatly reducing the cost and expanding the scope of knowledge engineering for legal reasoning. This, it is claimed, is most likely to be achieved via formalization of various sublanguages of legal discourse. SeaSpeak is an example of such a sublanguage and it appears to be amenable to full formalization. Short of that, much can be done with partial formalization and semistructured documents. The paper presents a tabular format for message expression, motivated by a formal agent communication language.
3114143
Interactive Execution Monitoring of Agent Teams
There is an increasing need for automated support for humans monitoring the activity of distributed teams of cooperating agents, both human and machine. We characterize the domain-independent challenges posed by this problem, and describe how properties of domains influence the challenges and their solutions. We will concentrate on dynamic, data-rich domains where humans are ultimately responsible for team behavior. Thus, the automated aid should interactively support effective and timely decision making by the human. We present a domain-independent categorization of the types of alerts a plan-based monitoring system might issue to a user, where each type generally requires different monitoring techniques. We describe a monitoring framework for integrating many domain-specific and task-specific monitoring techniques and then using the concept of value of an alert to avoid operator overload. 
 
We use this framework to describe an execution monitoring approach we have used to implement Execution Assistants (EAs) in two different dynamic, data-rich, real-world domains to assist a human in monitoring team behavior. One domain (Army small unit operations) has hundreds of mobile, geographically distributed agents, a combination of humans, robots, and vehicles. The other domain (teams of unmanned ground and air vehicles) has a handful of cooperating robots. Both domains involve unpredictable adversaries in the vicinity. Our approach customizes monitoring behavior for each specific task, plan, and situation, as well as for user preferences. Our EAs alert the human controller when reported events threaten plan execution or physically threaten team members. Alerts were generated in a timely manner without inundating the user with too many alerts (less than 10% of alerts are unwanted, as judged by domain experts).
7230571
Image Representation Using 2D Gabor Wavelets
This paper extends to two dimensions the frame criterion developed by Daubechies for one-dimensional wavelets, and it computes the frame bounds for the particular case of 2D Gabor wavelets. Completeness criteria for 2D Gabor image representations are important because of their increasing role in many computer vision applications and also in modeling biological vision, since recent neurophysiological evidence from the visual cortex of mammalian brains suggests that the filter response profiles of the main class of linearly-responding cortical neurons (called simple cells) are best modeled as a family of self-similar 2D Gabor wavelets. We therefore derive the conditions under which a set of continuous 2D Gabor wavelets will provide a complete representation of any image, and we also find self-similar wavelet parametrization which allow stable reconstruction by summation as though the wavelets formed an orthonormal basis. Approximating a "tight frame" generates redundancy which allows low-resolution neural responses to represent high-resolution images.