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A number of automated reasoning systems find their basis in process control engineering. These programs are often model-based and use individual frames to represent component functionality. This representation scheme allows the process system to be dynamically monitored and controlled as the reasoning system need only simulate the behavior of the modeled system while comparing its behavior to real-time data. The knowledge acquisition task required for the construction of knowledge bases for these systems is formidable because of the necessity of accurately modeling hundreds of physical devices. We discuss a novel approach to the capture of this component knowledge entitled automated knowledge generation (AKG) that utilizes constraint mechanisms predicated on physical behavior of devices for the propagation of truth through the component model base. A basic objective has been to construct a complete knowledge base for a model-based reasoning system from information that resides in computer-aided design (CAD) databases. If CAD has been used in the design of a process control system, then structural information relating the components will be available and can be utilized for the knowledge acquisition function. Relaxation labeling is the constraint-satisfaction method used to resolve the functionality of the network of components. It is shown that the relaxation algorithm used is superior to simple translation schemes.

Automated development of models for use in computer simulations of engineered systems (e.g. electronic, power, thermal, process systems, etc.) can represent a significant advantage to system designers and troubleshooters. The fact that most modern systems have been designed in Computer-Aided Design (CAD) environments represents a unique opportunity for automatically generating a model from the electronic representation of a system. Models generally require definition of the system structure (i.e. component connectivity) and of the behavioral description of its components. With some exceptions, determination of the system connectivity from a CAD representation is a relatively uncomplicated procedure. However, the assignment of a functional behavior to each component of the system depicted in the CAD representation is a significant problem. This is because behavioral information is usually not included in the CAD representation of the system, as it is not required by the typical users of the CAD graphic output. The overall issue addressed in this paper, therefore, is the determination of the correct behavioral attributes for the components making up the modeled system. This will be addressed through the identifcation and matching of system components to elements of an external base of generic component knowledge. The components' behavioral representation (i.e. transfer function) will be set equal to that of its matching element in this external database. The compatibility of a hard-to-identify system component with its (known) neighboring components can be used to shed some light on its identity. Component compatibility can also be used to determine correct connectivity when that defined by the CAD database is incorrect. This compatibility can be determined through the use of domain (system) knowledge, in the form of system theory and/or practice. The representation of this knowledge as a series of constraints is the focus of this paper. Verification of this technique using a testbed system is also reported here.

OBJECTIVE To determine the outcome of patients with end-stage chronic renal failure treated by live donor renal transplantation at the Royal Melbourne Hospital and Royal Children's Hospital between 1973 and 1991, during which time two distinct immunosuppressive regimens were used. DESIGN Data about live donor renal transplant recipients were retrieved from the Australian and New Zealand Dialysis and Transplantation Association Registry, to which we have submitted data on all transplant recipients at six monthly intervals since the commencement of our dialysis and transplant programs. PATIENTS Seventy-two patients with chronic renal failure who received live donor renal transplants during the 19 years from February 1973 to February 1992 were included. MAIN OUTCOME MEASURES Patient survival, transplant survival, transplant function, change in prednisolone requirements, and duration of hospital stay. RESULTS The first 32 patients were treated with immunosuppressive regimens based on combinations of prednisolone and azathioprine ("dual therapy"), while the next 40 patients were treated with combinations of cyclosporin, prednisolone and azathioprine ("triple therapy"). Survival of patients in each group five years after transplantation was 97%. Actuarial graft survival at 5, 10 and 15 years in the dual therapy group was 58%, 52% and 47%, compared with a 5-year actuarial graft survival in the triple therapy group of 96%. There was no statistically significant difference in renal transplant function between the two groups within the first 6 years after transplantation. Twelve of 26 patients (46%) treated initially with triple therapy were able to stop treatment with prednisolone within 12 months of transplantation. Median hospital stay was 12 (range, 6-35) days during the period 1973-1985 and 8 (range, 5-20) days for the 1985-1992 period. CONCLUSION Live donor renal transplantation has provided a highly satisfactory means of treating patients with end-stage chronic renal failure in the short and long term. Our recent experience indicates that excellent patient and graft survival and adequate renal function can be achieved by treating live donor renal transplant recipients with a triple immunosuppressive regimen of low dose cyclosporin, prednisolone and azathioprine.

A set of computer simulation projects that have been assigned at various times during offerings of an advanced graduate level course on machine perception is discussed. The format of the projects is presented, and student results are discussed. The projects are novel in that they require advanced techniques of machine vision and are open-ended in that there are no specific solutions. The problems represent the mainstream of machine perception research without requiring more effort than is possible in a one semester course. Students have responded with algorithms developed in a variety of computer languages and on various machines. >

A substantial amount of work has recently been completed at the University of Central Florida in the development of an Artificial Neural Network (ANN) simulation environment that overcomes traditional implementation problems normally associated with these types of programs. Researchers addressing the development and application of ANN systems seek modifiability, expansibility and platform independence. Our system allows for these elements as well as parallel execution when a parallel hardware is available. This is accomplished by use of object-oriented programming and a Computer Aided Software Engineering (CASE) approach to the development environment that allows the user to modify the software describing the ANN model without understanding of the overall implementation details. A sophisticated Graphical User Interface (GUI) is provided to allow rapid construction and evaluation of complex large-scale neural models.

A visual display taxonomy guide has been developed allowing a simulation designer to estimate requirements and cost ranges based on visual media selections and human visual limitations. The taxonomy was built from diverse research findings in training system development, instructional design, and human visual perception and performance studies. Results were coupled to basic engineering hardware design constraints associated with computer driven visual display systems. This approach yielded a decision structure based on a user query system and a list of outcomes based on those choices. The resulting list of outcomes is based on a set of training, perceptual and performance correlates of image specifications and display design characteristics. The user interface of the taxonomy was automated using a knowledge-based shell that illustrates and guides the specification process.

Visual display systems have become so advanced with available options, it is difficult to decide which type of system is needed. Traditionally, the choice has been to select the system with the greatest level of functional and physical fidelity that can be procured. While most would assume that more realism results in better training and performance, research (Dwyer, 1972; Marsh, 1983; Richey, 1986) suggests otherwise. Realism in a display system may serve to be more distracting than helpful, depending upon the training objective. The initial intent of this project was to locate any and all information pertaining to visual display characteristics as they relate to human visual functions or to visual training requirements. A selected literature search was conducted to locate relevant information, data bases or taxonomies that relate the above information. No current taxonomy of this kind was located; therefore, the efforts of the project turned in the direction of formulating a taxonomic structure based on information derived from various disciplines such as instructional technology, human psychology, and computer engineering. General guidelines only, with no specific information, pertaining to the selection of visual media for given situations were found in the instructional technology literature. Based on those guidelines, four general types of presentation media were selected: alphanumerics, 2-dimensional graphics, 3-dimensional graphics, and scene quality. Next, display specifications for these presentations were identified through the aid of engineering and vendor-provided design parameters. Finally, human limitations were applied and psychophysical transformations allowed the determination of final display descriptions.

Sirolimus is an immunosuppressive agent that offers potentially significant benefits for young transplant patients facing life-long treatment. Its action of reducing cell proliferation may reduce the risk of chronic allograft nephropathy and posttransplant neoplasia. Twenty-nine children were converted from calcineurin inhibitors to sirolimus after renal transplantation and followed for a minimum of 12 months. Glomerular filtration increased transiently in those converted before 12 months after transplantation but not in those converted later, when chronic histological changes had developed. Mild acute rejection occurred after conversion in 10%, and side effects led to cessation of sirolimus in 31%. Anemia occurred in 55% of patients and responded well to darbepoetin. Most side effects (anemia, hypercholesterolemia, mouth ulcers, and myalgias) became less severe with time. The number of antihypertensive drugs required decreased significantly on sirolimus. Although side effects are frequent on sirolimus, in the majority of children, they are mild enough to allow the patient to continue taking the drug, and for these children the long-term benefits are potentially valuable.

The health and continued existence of coral reef ecosystems are threatened by an increasing array of environmental and anthropogenic impacts. Coral disease is one of the prominent causes of increased mortality among reefs globally, particularly in the Caribbean. Although over 40 different coral diseases and syndromes have been reportedworldwide, only a few etiological agents have been confirmed; most pathogens remain unknown and the dynamics of disease transmission, pathogenicity and mortality are notunderstood. Causal relationships have been documented for only a few of the coral diseases, while new syndromes continue to emerge. Extensive field observations by coralbiologists have provided substantial documentation of a plethora of new pathologies, but our understanding, however, has been limited to descriptions of gross lesions with names reflecting these observations (e.g., black band, white band, dark spot). To determine etiology, we must equip coral diseases scientists with basic biomedical knowledge and specialized training in areas such as histology, cell biology and pathology. Only throughcombining descriptive science with mechanistic science and employing the synthesis epizootiology provides will we be able to gain insight into causation and become equipped to handle the pending crisis.One of the critical challenges faced by coral disease researchers is to establish a framework to systematically study coral pathologies drawing from the field of diagnosticmedicine and pathology and using generally accepted nomenclature. This process began in April 2004, with a workshop titled Coral Disease and Health Workshop: Developing Diagnostic Criteria co-convened by the Coral Disease and Health Consortium (CDHC), a working group organized under the auspices of the U.S. Coral Reef Task Force, and the International Registry for Coral Pathology (IRCP). The workshop was hosted by the U.S. Geological Survey, National Wildlife Health Center (NWHC) in Madison, Wisconsin and was focused on gross morphology and disease signs observed in the field. A resounding recommendation from the histopathologists participating in the workshop was the urgent need to develop diagnostic criteria that are suitable to move from gross observations to morphological diagnoses based on evaluation of microscopic anatomy. (PDF contains 92 pages)

Summary form only given.The world is currently witnessing the arrival of a new domain in telecommunications, that of network and media convergence. This new field was motivated by the desire to provide a unified interface capable of supporting various services across the many types of delivery networks that are available. This has resulted in a rush to develop and implement new standards and protocols that can support a multiplicity of media services such as the "Triple Play" (voice, data and video), and the "Quadruple Play" (voice, data, video and mobility). Among the emerging standards is the IP Multimedia Subsystem (IMS) that is an overlay control subsystem across heterogeneous access networks. IMS will enable fixed and mobile convergence and support service mobility. On the practical side, an intense competition is underway among fixed and mobile network operators where each is fighting to be the leader in providing fixed-mobile convergence in the least amount of time. Concurrently, another competition related to application convergence is gathering momentum among Internet Service Providers and Content Providers to win customer ownership. One of the other important components in the convergence realm is the need for adopting security techniques and policies that ensure confidentiality, privacy, anonymity, availability and accountability. Clearly, the above activities cannot be sustained and enhanced without developing an appropriate regulatory framework that defines the roles, rights and responsibilities of all involved parties. In this talk, many crucial issues underlying network and media convergence are identified. We also examine current activities and track future trends that will help us grasp the bigger picture of this new and exciting realm - a development that is expected to shape the way we live for many years to come.

Signal reconstruction from the measurements of its Fourier transform magnitude remains an important and difficult problem that occurs in different areas in signal processing. Among all the approaches developed to solve this problem, the iterative transform algorithms are currently the most efficient. However, these algorithms suffer from major drawbacks such as stagnation, slow convergence, and high computational cost that limit their practical application. In this brief, we introduce a wavelet adaptation of the general iterative algorithm where the problem is decomposed into different resolution levels and the image is reconstructed following a coarse-to-fine strategy. We show that the proposed approach can significantly improve the performance of the existing algorithms while dramatically reducing their computational complexity.

A proposed system for a visual tracker is presented that relies on information developed from previous tracking scenarios stored in a knowledge base to enhance tracking performance. The system is comprised of a centroid tracker front end that supplies segmented image features to a data reduction algorithm and subsequently to a track processor operating under one of two modes, learn or track. While in learn mode, a human operator provides identification cues for membership in a long-term storage relation within a knowledge base. In track mode the system operates autonomously with a cognitive processing algorithm replacing the human operator. The autonomous system functions as a correlation tracker by comparing processed input to data that was stored in the knowledge base during learn mode. Results determined from the classification generate tracker directives that either enhance the current track or cause the tracker to search for alternate targets based on a global target tracking list.

This study examined how often children with persistent familial hematuria were from families where hematuria segregated with the known genetic locus for the condition known as benign familial hematuria or thin basement membrane nephropathy (TBMN) at COL4A3/COL4A4. Twenty-one unrelated children with persistent familial hematuria as well as their families were studied for segregation of hematuria with haplotypes at the COL4A3/COL4A4 locus for benign familial hematuria and at the COL4A5 locus for X-linked Alport syndrome. Eight families (38%) had hematuria that segregated with COL4A3/COL4A4, and four (19%) had hematuria that segregated with COL4A5. At most, eight of the other nine families could be explained by disease at the COL4A3/COL4A4 locus if de novo mutations, non-penetrant hematuria or coincidental hematuria in unaffected family members was present individually or in combination. This study confirms that persistent familial hematuria is not always linked to COL4A3/COL4A4 (or COL4A5) and suggests the possibility of a further genetic locus for benign familial hematuria. This study also highlights the risk of excluding X-linked Alport syndrome on the basis of the absence of a family history or of kidney failure.

Treatment of children with steroid-dependent nephrotic syndrome (SDNS) continues to be a challenge when relapses recur after treatment with cyclophosphamide and side effects or non-compliance make steroids and cyclosporin unsatisfactory. We treated 12 patients with intravenous vincristine for SDNS in a regime of 1-1.5 mg/m2 weekly for 4 weeks then monthly for 4 months. Four of the 5 patients in relapse when commencing vincristine remitted within 2 doses. Comparing relapse frequency in the 12 months before and after vincristine, there was a reduction from 4 to 1.5 (p=0.004) relapses per year. Median sustained remission was 5 months, but 1 frequently relapsing patient remains in remission 4 years after vincristine. Vincristine was also successfully used in 1 or 2 doses at weekly intervals for subsequent relapses in 5 patients. Side effects were minimal in most cases. Abdominal pain occurred in 2 patients who commenced vincristine at 1.5 mg/m2, but resolved when continued at 1 mg/m2. We felt vincristine had a role in a subset of children with challenging SDNS administered as 1 mg/m2 weekly for 4 weeks then 1.5 mg/m2 monthly for 4 months. Vincristine allowed steroid- and cyclosporin-sparing, contributed to long-term remission in some patients, and was especially valuable in children with poor compliance with oral medication. Many patients expressed a preference for a few doses of vincristine rather than a standard course of oral prednisolone or cyclosporin.

Kimura disease is a rare inflammatory condition of unknown aetiology. It typically presents in young Asian males with the triad of non-tender subcutaneous swellings in the head and neck region, peripheral eosinophilia and raised serum IgE. About 16% of cases have associated renal disease. We present the case of a 10-year-old boy with a past history of steroid responsive, frequently relapsing nephrotic syndrome who developed a right submandibular swelling and eosinophilia. Kimura disease was diagnosed on the basis of clinical and histological findings. The condition recurred during relapses of nephrotic syndrome. Because of poor adherence with oral medication, our patient was treated with intravenous vincristine with synchronous remissions of his nephrotic syndrome and Kimura swellings on each occasion.