Candidate Architectures Research Articles

Modeling interactions between filial imprinting and a predisposition using genetic algorithms and neural networks

I present a neural network model of the complex interactions between filial imprinting and a naive preference for heads and necks in domestic chicks. The fixed weights in the network were evolved in a genetic algorithm simulation which emphasized the survival value of both innate and learned information: having the networks recognize their “mothers”. The architecture and genetic algorithm regimen were able to produce five different behaviors exhibited by chicks in laboratory experiment emulations dissimilar to the training regimen used in the genetic algorithm simulations. These networks learn about their own biases, given random inputs, as well as learning about their environments through simulated visual inputs, and these kinds of learning interact to produce the behaviors seen in chicks. Thus, this architecture, in the context of selection for an ability to distinguish something that might be a mother from other objects in the environment, is a candidate architecture for the neural system underlying the full range of imprinting-related behaviors in chicks.

Synthesis of Plantwide Control Systems Using a Dynamic Model and Optimization

An optimization-based approach to synthesizing plantwide control architectures is discussed. The approach assumes that a dynamic model is available, and it extends earlier work. The plantwide controller is synthesized in three stages involving fast and slow safety variables to be controlled, followed by product variables. In each stage a mixed integer linear program is solved to generate candidate architectures. The objective function involves a tradeoff between manipulated variable moves and transient response area. The integers in the formulation determine the control architecture, and integer cuts are employed to generate second best, third best, etc., candidate solutions. Controlling component balances and adding unit operation controls completes the plantwide control system design. The Tennessee Eastman process is used to illustrate the synthesis procedure.

Reliability and cost‐effectiveness of a telecommunication network composed of distributed switching nodes and high‐performance control nodes

AbstractWe have already proposed DONA‐α (distributed object‐oriented network architecture) as a candidate architecture for future telecommunications networks. A node in a conventional network contains both control and switching subsystems. In DONA‐α, these subsystems are physically separated, as independent nodes, so the network is composed of a small number of high‐performance control nodes that each control numerous low‐capacity switching nodes.Since service faults in a large‐scale public telecommunications network can have a severe effect on human society, the reliability of conventional networks is improved by designing redundancy into the network architecture. However, this raises the network configuration cost.DONA‐α should reduce network configuration costs without drastically decreasing the reliability. This is because each switching node will accommodate fewer subscribers than a conventional subscriber node, so it will be possible to reduce the degree of redundancy.In this paper, we examine the relationship between reliability and the degree of redundancy in the architecture of a DONA‐α network. We also evaluate the reliability and cost‐effectiveness of a DONA‐α network compared with a conventional network. © 2001 Scripta Technica, Electron Comm Jpn Pt 1, 84(11): 1–15, 2001

Communication system architecture for planetary exploration

Future human missions to Mars will require effective communications supporting exploration activities and scientific field data collection. Constraints on cost, size, weight, and power consumption for all communications equipment make optimization of these systems very important. These information and communication systems connect people and systems together into coherent teams performing the difficult and hazardous tasks inherent in planetary exploration. The communication network supporting vehicle telemetry data, mission operations, and scientific collaboration must have excellent reliability and flexibility. We propose hybrid communication architectures consisting of space-based links, a surface-based deployable mid-range communications network and a cluster of short-range links to solve the problems of connectivity and bandwidth, while meeting the other constraints of weight and power. A network of orbiting satellites could cover much of the planet surface, but this space-based capability may not be optimal for cost or performance. Specifically, a minimal space-based capability can be augmented using mobile cellular repeaters deployable by robots and human EVA. This method results in an increase in the number of radio nodes, but the distances separating them is decreased. This results in a significant increase in bandwidth and decrease in radio power, and therefore, node size, complexity, and power consumption. This paper will discuss the results of field testing such hybrid radio systems for the support of scientific surveys. System analysis of design tradeoffs will yield insight into optimal solutions that will be compared to other approaches providing a method of effectively evaluating new candidate architectures.

DG2VHDL: A Tool to Facilitate the High Level Synthesisof Parallel Processing Array Architectures

We present DG2VHDL, a design tool which can automatically translate abstract algorithmic descriptions, known as Dependence Graphs, to synthesizable VHDL models and testbenches representative of distributed memory and control processor arrays, known as Signal Flow Graphs. This translation facilitates the rapid exploration of the large space of available parallel architectures for a given problem and frees the designer from having to code and test separately, using a Hardware Description Language, every candidate architecture under consideration. It is shown that the quality and scalability of the automatically generated VHDL models is near optimal, in the sense that the time required to synthesize them as well as the area of the resulting hardware grows at the lowest possible rate with the problem size. This makes possible the high level synthesis of processor arrays for large size real world problems, such as the computation of the Discrete Wavelet Transform and the estimation of Higher Order Statistics, that are presented as case studies.

A flexible analog memory address list manager for PHENIX

A programmable analog memory address list manager has been developed for use with all analog memory-based detector subsystems of PHENIX. The unit provides simultaneous read/write control, cell write-over protection for both a Level-1 trigger decision delay and digitization latency, and re-ordering of AMU addresses following conversion, at a beam crossing rate of 105 ns. Addresses are handled such that up to 5 Level-1 (LVL-1) events can be maintained in the AMU without write-over. Data tagging is implemented for handling overlapping and shared beam-event data packets. Full usage in all PHENIX analog memory-based detector subsystems is accomplished by the use of detector-specific programmable parameters-the number of data samples per valid LVL-1 trigger and the sample spacing. Architectural candidates for the system are discussed with emphasis on implementation implications. Details of the design are presented including application specifics, timing information, and test results from a full implementation using field programmable gate arrays (FPGAs).

Comparison of Real-Time Ionospheric Algorithms for a GPS Wide-Area Augmentation System (WAAS)*

The Federal Aviation Administration (FAA) Satellite Program Office is developing a GPS Wide-Area Augmentation System (WAAS) to support a precision approach capability down to or near the lowest Category I (CAT I) decision height (DH) of 200 ft. In one of the candidate architectures under development, a vector of corrections is sent to the user via geostationary communications satellites (e.g., Inmarsat). This correction vector includes components for ionospheric, clock, and ephemeris corrections. The purpose of this paper is to evaluate the performance of the grid-based algorithms and other real-time ionospheric algorithms that could be implemented at the ground ionospheric reference stations, as well as at the airborne receiver. Results show that all of the ionospheric algorithms used in this paper (grid-based, least-squares, and spherical harmonics) provide roughly equivalent performance. Based on an extensive data collection program, the error in estimating ionospheric delay is derived. An analysis of WAAS accuracy performance is also presented.

The Manhattan Street Network: a high performance, highly reliable metropolitan area network

Abstract In this paper we introduce the Manhattan Street Network (MS_Net) and show it to be a strong candidate architecture for a high-speed Metropolitan Area Network (MAN). We compare the MS_Net to other MAN architectures, specifically FDDI and DQDB, and show it to be superior in terms of reliability, throughout and privacy of communications. We discuss the failure recovery mechanisms in each of these networks and their operation under multiple failures. A comparison of the throughout performance under uniform and non-uniform traffic scenarios is provided. We also compare the abilities of these three networks to provide secure service and privacy. Finally, we discuss a number of outstanding problems in the MS_Net and the proposed solutions for them.

Supporting interoperability between medical knowledge-based systems: Experience from pilot implementations

Interoperability may be defined as the ability of knowledge-based systems to function together in a symbiotic manner. Cooperativity implies interoperability but with the added benefit that the output quality of the cooperative network exceeds the overall performance of the participating sub-systems. A number of candidate architectures to support interoperability and cooperativity between medical knowledge-based systems in laboratory medicine domains are now becoming available. Using rapid prototyping techniques, we have demonstrated the feasibility of one of these approaches by carrying out pilot implementations in two unrelated laboratory medicine domains (an internal consistency checking system for validating patients' results in the laboratory and a system for generating alarms and alerts in high dependency units based on laboratory data). The results of this study are discussed in the context of the available techniques so as to provide a basis for further development of cooperative systems in laboratory medicine.

Evaluation and comparison of triple and quadruple flight control architectures

Fault tolerances of a triple flight control architecture are defined and compared to that of a quadrupole type, and the impact of worst case failures on the transient response of an aircraft is investigated. Insights in computing fault coverage are discussed. Two coverage models have been used to compute the probability of loss of control (PLOC) and the probability of mission abort (PMA) for candidate architectures. Results indicate that both triple and quadruple architectures can meet the fault tolerance requirements with an acceptable level of transients upon first and second failures. Triple architectures will require a higher level of fault detection, isolation, and accommodation coverage than quadruple architectures and produce substantially larger transients upon second failure. >

Deep space telecommunications, navigation, and information management: Support of the space exploration initiative

The United States Space Exploration Initiative (SEI) calls for the charting of a new and evolving manned course to the Moon, Mars, and beyond. This paper discusses key challenges in providing effective deep space telecommunications, navigation, and information management (TNIM) architectures and designs for Mars exploration support. The fundamental objectives are to provide the mission with means to monitor and control mission elements, acquire engineering, science, and navigation data, compute state vectors and navigate, and move these data efficiently and automatically between mission nodes for timely analysis and decision-making. Although these objectives do not depart, fundamentally, from those evolved over the past 30 years in supporting deep space robotic exploration, there are several new issues. This paper focuses on summarizing new requirements, identifying related issues and challenges, responding with concepts and strategies which are enabling, and, finally, describing candidate architectures, and driving technologies. The design challenges include the attainment of: 1) manageable interfaces in a large distributed system, 2) highly unattended operations for in-situ Mars telecommunications and navigation functions, 3) robust connectivity for manned and robotic links, 4) information management for efficient and reliable interchange of data between mission nodes, and 5) an adequate Mars-Earth data rate.

Management and control of CCSDS cross-support services

A candidate architecture for management and control of Consultative Committee for Space Data Systems (CCSDS) services is presented. An operations concept is presented. Candidate management procedures and a management information base for the resources to be managed are suggested. This architecture is based on concepts of network management of computer and telecommunication networks which are under study by other international standards bodies such as the International Organization for Standardization (ISO) and the International Telephone and Telegraph Consultative Committee (CCITT).< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Reliability &amp; Safety Analysis of a Fault-Tolerant Controller

This paper analyzes a fault-tolerant, microprocessor-based controller for an electric wheelchair. Two candidate architectures are considered, including reconfigurable duplication and stand-by sparing. The difference in the reliability and safety of the two candidates is determined through the use of Markov models. Safety is paramount in the wheelchair application because of the need to protect the physically disabled wheelchair user;reliability by itself is insufficient for selecting an appropriate architecture in this application. The results show that reconfigurable duplication is safer than standby sparing even though standby sparing is more reliable. Because of the better safety, reconfigurable duplication is the preferred approach for the wheelchair application. Safety is extremely important in the selection of a fault-tolerant architecture for the electric wheelchair control system. Standby sparing provides a conceptually simple approach that achieves a higher reliability than reconfigurable duplication. However, reconfigurable duplication has a higher safety for a given fault coverage. Because of the need for safety in the electric wheelchair control system, reconfigurable duplication is the selected approach.

An architect's view

NSPI JournalVolume 19, Issue 2 p. 14-33 Article An architect's view Don Strauch, Don Strauch Seracuse Lawler and Partners, Incorporated Denver, Colorado Don Strauch is project architect and company principal for Seracuse Lawler and Partners, Incorporated. Since its founding in Denver, Colorado in 1966, Seracuse Lawler and Partners has achieved a reputation for architectural excellence in a wide variety of buildings, making the company a leading architectural candidate for the Mountain Bell Training Center.Search for more papers by this author Don Strauch, Don Strauch Seracuse Lawler and Partners, Incorporated Denver, Colorado Don Strauch is project architect and company principal for Seracuse Lawler and Partners, Incorporated. Since its founding in Denver, Colorado in 1966, Seracuse Lawler and Partners has achieved a reputation for architectural excellence in a wide variety of buildings, making the company a leading architectural candidate for the Mountain Bell Training Center.Search for more papers by this author First published: March 1980 https://doi.org/10.1002/pfi.4180190210 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Volume19, Issue2March 1980Pages 14-33 RelatedInformation

Application of the military computer family architecture selection criteria to the PR1ME P400

The evluation criteria and procedures developed by the Army-Navy Comittee on military computer family architecture selection and utilized by that committee in the evaluation of nine candidate architectures were applied to the PR1ME 400 computer system. The result of this project provided a better understanding of the PR1ME 400 architecture, while at the same time, highlighted some of the problems in interpreting the committees' evaluation criteria and the problems in applying in such an evaluation procedure.