A novel Multi-Level Partitioning (MLP) technique taking into account real-world constraints for hardware-software partitioning in Distributed Embedded Multiprocessor Systems (DEMS) is proposed. This MLP algorithm uses a gradient metric based on hardware-software cost and performance as the core metric for selection of optimal partitions and consists of three nested levels. The innermost level is a simple binary search that allows quick evaluations of a large number of possible partitions. The middle level iterates over different possible allocations of processors (that execute software) to subsystems. The outermost level iterates over the number of processors and the hardware cost range. Heuristics are applied to each level to avoid the expensive exhaustive search. The application of MLP as a recently purposed Distributed Embedded System Codesign (DESC) methodology shows its feasibility. Comparisons between real-world examples partitioned using MLP and using other existing techniques demonstrate contrasting strengths of MLP. Sharing, clustering, and hierarchical system model are some important features of MLP, which contribute towards producing more optimal partition results.

This work elucidates the evolution of three generations of the laboratory information system in the National Taiwan University Hospital, which were respectively implemented in an IBM Series/1 minicomputer, a client/server and a plug-and-play HL7 interface engine environment respectively. The experience of using the HL7 healthcare information exchange in the hospital information system, laboratory information system, and automatic medical instruments over the past two decades are illustrated and discussed. The latest design challenge in developing intelligent laboratory information services is to organize effectively distributed and heterogeneous medical instruments through the message gateways. Such experiences had spread to some governmental information systems for different purposes in Taiwan; besides, the healthcare information exchange standard, software reuse mechanism, and application service provider adopted in developing the plug-and-play laboratory information system are also illustrated.

A formal system-level synthesis model for the concurrent object-oriented design of parallel computer systems, called Multi-token Object-oriented Bi-directional net (MOBnet), is proposed. The MOBnet model extends the standard Petri net by defining (1) multiple tokens to represent different kinds of synthesis control information, (2) object-oriented nodes (places) to denote the system parts under synthesis, and (3) bi-directional arcs to model the design completion check and synthesis rollback operations. In this paper, we first show that MOBnet can serve as a pre-fabrication design methodology analysis tool in ways such as class hierarchy construction, design specification comparison, reachability analysis, and concurrent process management and analysis. We then formally prove MOBnet to be a valid model for concurrent synthesis and give experimental application examples to verify. Finally, solution schemes for the design completion check and synthesis rollback problems are formally validated by analyzing the dynamic behavior of MOBnet, and experimentally illustrated through examples.

This paper investigates the problem of scheduling parallel tasks" with consideration of communication cost on an m-processor system, where processors are assumed to be identical and tasks being scheduled are independent such that they can run on more than one processor simultaneously. Once a task is processed in parallel, its finish time will be speeded up, but communication cost will also be incurred and should be taken into account. To find a schedule with minimum finish time for the parallel tasks scheduling problem is NP-hard. Therefore, in this paper, we will propose a heuristic algorithm for this kind of problem and derive its performance bounds for two different cases of applications, respectively.

This paper illustrates a feasible health informatics domain knowledge management process which helps gather useful technology information and reduce many knowledge misunderstandings among engineers who have participated in the IBM mainframe rightsizing project at National Taiwan University (NTU) Hospital. We design an asynchronously sharing mechanism to facilitate the knowledge transfer and our health informatics domain knowledge management process can be used to publish and retrieve documents dynamically. It effectively creates an acceptable discussion environment and even lessens the traditional meeting burden among development engineers. An overall description on the current software development status is presented. Then, the knowledge management implementation of health information systems is proposed.

This CMOS transceiver IC exploits the superheterodyne architecture to implement a low-cost RF front-end with only 6.25 mm2 die area for IEEE 802.11b standard. The transceiver is implemented in 0.25 µm CMOS process with 2.7 V supply voltage, and achieves a -86 dBm 11 Mb/s receive sensitivity and a 2 dBm transmit output power.

Most of current codesign tools or methodologies only support validation in the form of cosimulation and testing of design alternatives. The results of hardware-software codesign of a distributed system are often not verified, because they are not easily verifiable. In this paper, we propose a new formal coverification approach based on linear hybrid automata, and an algorithm for automatically converting codesign results to the linear hybrid automata framework. Our coverification approach allows automatic verification of real-time constraints such as hard deadlines. Another advantage is that the proposed approach is suitable for verifying distributed systems with arbitrary communication patterns and system architecture. The feasibility of our approach is demonstrated through several application examples. The proposed approach has also been successfully used in verifying deadline violations when there are inter-task communications between tasks with different period lengths.

Due to the large number of I/O's in a Ball-Grid-Array (BGA) package, routing becomes more and more an important work. A ring-based router for the BGA package is presented in this paper to interconnect each I/O pad of a chip to a corresponding ball distributed on the substrate area. The major phases for the router consist of layer assignment, topological routing, and physical routing. Using this router, we can generate an even distribution of planar and any-angle wires to improve manufacturing yield. We have also conducted various testing examples to verify the efficiency of this router. Experiments show that the router produces very good results, far better than the manual design, thus it can be applied to the practical packaging of integrated circuits.

In this paper, a new family of interconnection networks which we call the Incrementally Extensible Twisted Cube (IETQ) is proposed. The topology of this network is a novel generalization of the twisted cube. It inherits all the merits but without the limitations owned by a twisted cube. First, this proposed IETQ is incrementally extensible and can be adapted for use in any number of nodes; therefore, this network is particularly well suited for the design of a distributed communication network with an arbitrary number of nodes. Second, the vertex connectivity of IETQ is n. Measured by this vertex connectivity, we demonstrate that this network is optimally fault-tolerant . And it is almost regular, because the difference between the maximum and minimum degree of any node in an IETQ is at most one. A shortestpath routing algorithm for IETQ is proposed to generate path for any given pair of vertices in the network. Third, comparing with most of the other competitors, the diameter of this IETQ network is only half in size. This low diameter helps to reduce the internode communication delay. Moreover, IETQ also possesses the property of a pancyclic network. This attractive property would enable us to map rings of any length into the proposed network.

The hardware-software codesign of distributed embedded systems is a more challenging task, because each phase of codesign, such as copartitioning, cosynthesis, cosimulation, and coverification must consider the physical restrictions imposed by the distributed characteristics of such systems. Distributed systems often contain several similar parts for which design reuse techniques can be applied. Object-oriented (OO) codesign approach, which allows physical restriction and object design reuse, is adopted in our newly proposed Distributed Embedded System Codesign (DESC) methodology. DESC methodology uses three types of models: Object Modeling Technique (OMT) models for system description and input, Linear Hybrid Automata (LHA) models for internal modeling and verification, and SES/workbench simulation models for performance evaluation. A two-level partitioning algorithm is proposed specifically for distributed systems. Software is synthesized by task scheduling and hardware is synthesized by system-level and object-oriented techniques. Design alternatives for synthesized hardware-software systems are then checked for design feasibility through rapid prototyping using hardware-software emulators. Through a case study on a Vehicle Parking Management System (VPMS), we depict each design phase of the DESC methodology to show benefits of OO codesign and the necessity of a two-level partitioning algorithm.