53235726
Integrating logic retiming and register placement
195837942
Optimum and heuristic data path scheduling under resource constraints
An integer linear programming model for the scheduling problem in high-level synthesis under resource constraints is presented. The following applications are considered: multicycle operations with nonpipelined or pipelined function units: mutually exclusive operations: functional pipelining: loop-folding; and scheduling under bus constraint. Besides the model, a new technique, called zone scheduling (ZS), is proposed to solve large-size problems. ZS partitions the distribution graph into several zones and sequentially solves the problems contained. A novel feature of this technique is that it schedules more than one control step at a time, allowing a more global view of a scheduling problem to be taken.<<ETX>>
53235373
Performance-optimal clustering with retiming for sequential circuits
16396963
Performance-driven interconnection optimization for microarchitecture synthesis
This paper addresses the interconnection synthesis problem in microarchitecture-level designs. With emphasis on the speed of data movement operations, we propose algorithms that take into consideration the effect of each data-transfer-to-bus binding on the data transfer delay time. The delay time is calculated as a function of both data source load and data carrier (bus) load. By balancing loads among hardware components, the data transfer delay time (hence the total execution time) is shortened. We consider two types of problems: resource-constrained binding and performance-constrained binding. Two integer linear programming (ILP) formulations are derived to optimally solve the problems. In order to speed up the computation, a bipartite weighted matching method for the resource-constrained binding and a greedy merging method for the performance-constrained binding are also proposed. Both the ILP formulation generators and the heuristics have been programmed. Experimental results indicate that the proposed algorithms are indeed very effective in optimizing the performance aspect of the interconnection design. >
6763648
An effective methodology for functional pipelining
We address the problem of given a loop behavior, a target initiation interval and resource constraints, scheduling a loop in a pipelined fashion such that the iteration time (turn-around time) is minimized. The iteration time is an important quality measure of a data path design because of its direct correlationship with both the storage and the control costs. Our scheduler starts with performing an As Soon As Possible Pipelined (ASAPp) scheduling without regard to the resource constraint. It then resolves the resource constraint violations, if there are any, by repeatedly rescheduling some operations.
195838317
Data path allocation based on bipartite weighted matching
Proposes a graph-theoretic approach for the data path allocation problem. The problem is decomposed into three subproblems: (1) register allocation, (2) operation assignment, and (3) connection allocation. The first two subproblems are modeled as two bipartite weighted matching problems and solved using the Hungarian method. The third subproblem is solved using a greedy method. It is shown that, by taking the other into consideration while solving one, equally satisfactory results can be obtained, regardless of the order in which (1) and (2) are performed. Two programs, LYRA and ARYL, are implemented which solve the subtasks in different orders. For register allocation, the approach is the first one to guarantee minimal use of registers while being able to take the interconnection cost into account. This research has demonstrated that the bipartite weighted matching algorithm is indeed a good solution for the data path allocation problem.<<ETX>>
29816088
GPRS-based WLAN authentication and auto-configuration
This paper proposes an authentication and auto-configuration mechanism for wireless LAN (WLAN) based on short message service of mobile telecommunications network. Our approach automates the authentication and WLAN configuration setup procedure without involving the users.
11056764
Integrating multi-agent negotiation to resolve constraints in fulfilling supply chain orders
Abstract As the order fulfillment process (OFP) in supply chains shifts to outsourcing paradigm, the OFP performance relies on the coordination among supply chain partners to reach executable and effective plans. The coordination of OFP among supply chain partners can be viewed as a distributed constraint satisfaction problem (DCSP). This study adds the multi-agent negotiation mechanism to enhance the existing methods to solve the DCSP, and then evaluates the integrated system’s performance through experimentation on the OFP in the context of the metal industry. The experimental results show that the integrated system outperforms the existing distributed constraint satisfaction algorithms in various demand patterns.
12722290
A survey and measurement-based comparison of bandwidth management techniques
This article gives a brief tutorial for bandwidth management systems; a survey of the techniques used by eight real-world systems, such as class-based queuing (CBQ), per-flow queuing (PFQ), random early detection (RED), and TCP rate control (TCR); a compact testbed with a set of methodologies to differentiate the employed techniques; and a detailed black-box evaluation. The tutorial describes the needs for the three types of policy rules: class-based bandwidth limitation, session-bandwidth guarantee, and inter/intra-class bandwidth borrowing. The survey portion investigates how the eight chosen commercial/open-source real systems enforce the three policy types. To evaluate the techniques, the designed testbed emulates real-life Internet conditions, such as many simultaneous sessions from different IPs/ports, controllable wide area network (WAN) delay and packet loss rate for each session, and different TCP source implementations. The performance metrics include accuracy of bandwidth management, fairness among sessions, robustness under Internet packet losses and different operating systems, inter/intra-class bandwidth borrowing, and voice over IP (VoIP) quality. The black-box test results demonstrate that (1) only the combination of CBQ+PFQ+TCR can solve the most difficult scenario (multiple sessions competing for the narrow 20kb/s class); (2) the TCR approach may degrade the goodput, fairness, and compatibility even under slight packet loss rates (0.5 percent); (3) without PFQ, TCR and RED have limited ability to isolate the sessions (especially for RED); (4) the G.729 VoIP quality over a 125kb/s access link becomes good only after exercising MSS-clamping to shrink the packet size of the background traffic down to 256 byte.
14820349
Per-user checkpointing for mobility database failure restoration
This paper studies the failure restoration of mobility database for Universal Mobile Telecommunications System (UMTS). We consider a per-user checkpointing approach for the home location register (HLR) database. In this approach, individual HLR records are saved into a backup database from time to time. When a failure occurs, the backup record is restored back to the mobility database. We first describe a commonly used basic checkpoint algorithm. Then, we propose a new checkpoint algorithm. An analytic model is developed to compare these two algorithms in terms of the checkpoint cost and the probability that an HLR backup record is obsolete. This analytic model is validated against simulation experiments. Numerical examples indicate that our new algorithm may significantly outperform the basic algorithm in terms of both performance measures.
16475094
A mixture model for estimating the local false discovery rate in DNA microarray analysis
MOTIVATION
Statistical methods based on controlling the false discovery rate (FDR) or positive false discovery rate (pFDR) are now well established in identifying differentially expressed genes in DNA microarray. Several authors have recently raised the important issue that FDR or pFDR may give misleading inference when specific genes are of interest because they average the genes under consideration with genes that show stronger evidence for differential expression. The paper proposes a flexible and robust mixture model for estimating the local FDR which quantifies how plausible each specific gene expresses differentially.


RESULTS
We develop a special mixture model tailored to multiple testing by requiring the P-value distribution for the differentially expressed genes to be stochastically smaller than the P-value distribution for the non-differentially expressed genes. A smoothing mechanism is built in. The proposed model gives robust estimation of local FDR for any reasonable underlying P-value distributions. It also provides a single framework for estimating the proportion of differentially expressed genes, pFDR, negative predictive values, sensitivity and specificity. A cervical cancer study shows that the local FDR gives more specific and relevant quantification of the evidence for differential expression that can be substantially different from pFDR.


AVAILABILITY
An R function implementing the proposed model is available at http://www.geocities.com/jg_liao/software