A Large Scale Computer-Based Educational System For The Seventies

A computer-based education system in use at the University of Illinois is described. Based on many years of teaching experience with this system and on several technological breakthroughs, a design for a large scale computer-based education system capable of serving up to 4,000 student terminals is presented. Working prototypes of a student console and a data distribution system are described. Finally, a cost estimate of the system is presented

Multipattern Consensus Regions in Multiple Aligned Protein Sequences and Their Segmentation

<p/> <p>Decomposing a biological sequence into its functional regions is an important prerequisite to understand the molecule. Using the multiple alignments of the sequences, we evaluate a segmentation based on the type of statistical variation pattern from each of the aligned sites. To describe such a more general pattern, we introduce multipattern consensus regions as segmented regions based on conserved as well as interdependent patterns. Thus the proposed consensus region considers patterns that are statistically significant and extends a local neighborhood. To show its relevance in protein sequence analysis, a cancer suppressor gene called p53 is examined. The results show significant associations between the detected regions and tendency of mutations, location on the 3D structure, and cancer hereditable factors that can be inferred from human twin studies.</p

Analysis of Free Energy Signals Arising from Nucleotide Hybridization Between rRNA and mRNA Sequences during Translation in Eubacteria

A decoding algorithm is tested that mechanistically models the progressive alignments that arise as the mRNA moves past the rRNA tail during translation elongation. Each of these alignments provides an opportunity for hybridization between the single-stranded, 3′-terminal nucleotides of the 16S rRNA and the spatially accessible window of mRNA sequence, from which a free energy value can be calculated. Using this algorithm we show that a periodic, energetic pattern of frequency 1/3 is revealed. This periodic signal exists in the majority of coding regions of eubacterial genes, but not in the non-coding regions encoding the 16S and 23S rRNAs. Signal analysis reveals that the population of coding regions of each bacterial species has a mean phase that is correlated in a statistically significant way with species (G + C) content. These results suggest that the periodic signal could function as a synchronization signal for the maintenance of reading frame and that codon usage provides a mechanism for manipulation of signal phase

REPLAB: A Study in Scientific Inquiry Using the PLATO System

Coordinated Science Laboratory was formerly known as Control Systems LaboratoryJoint Services Electronics Programs / DA 28 043 AMC 00073(E)Advanced Research Projects Agency through the Office of Naval Research / Nonr-3985(08

Identification of protein-coding sequences using the hybridization of 18S rRNA and mRNA during translation

We introduce a new approach in this article to distinguish protein-coding sequences from non-coding sequences utilizing a period-3, free energy signal that arises from the interactions of the 3′-terminal nucleotides of the 18S rRNA with mRNA. We extracted the special features of the amplitude and the phase of the period-3 signal in protein-coding regions, which is not found in non-coding regions, and used them to distinguish protein-coding sequences from non-coding sequences. We tested on all the experimental genes from Saccharomyces cerevisiae and Schizosaccharomyces pombe. The identification was consistent with the corresponding information from GenBank, and produced better performance compared to existing methods that use a period-3 signal. The primary tests on some fly, mouse and human genes suggests that our method is applicable to higher eukaryotic genes. The tests on pseudogenes indicated that most pseudogenes have no period-3 signal. Some exploration of the 3′-tail of 18S rRNA and pattern analysis of protein-coding sequences supported further our assumption that the 3′-tail of 18S rRNA has a role of synchronization throughout translation elongation process. This, in turn, can be utilized for the identification of protein-coding sequences

Predictive Modeling of End-User Quality of Service for Network Based Education

An important class of network based applications are systems which provide distance education and interactive learning. To be effective they must provide adequate Quality of Service (QoS) support and guarantees. Traditional QoS management approaches tend to focus on network performance and transport layer mechanisms (such as switching, or TCP/IP flow control). However, in the context of network-based education (NBE) it is very important to also address QoS from an end-user perspective. In this paper we regard user-level QoS violations as events that can be described using traditional and rare-event reliability and availability models. We advocate use of such models to predict QoS over the duration of NBE sessions, and based on that initiate appropriate risk resolution mechanisms (including re-negotiation of network-level parameters, and selection of content delivery modes which comply with the predicted QoS). We use the data from an operational wide area NBE system to illustrate the mo..

Reliability Behavior of a Large Network Based Education System

This paper presents a reliability and availability evaluation of a large Network Based Education (NBE) system called NovaNET. NovaNET is a wide area NBE system which serves thousands of users on a daily basis. A successful NBE system is expected to provide appropriate Quality of Service (QoS) guarantees to its users. Among the most important extended QoS parameters are system reliability and availability. Ever since its inception NovaNET has been providing its users with daily reports on system reliability and availability during scheduled user hours of operation. We present results from a study of NovaNET using 9 years of operational reliability and failure data. The data are used to discuss practical bounds on reliability and availability of a viable and successful NBE system. 1. Introduction An important class of network based applications which require service guarantees are distance learning and Network Based Education (NBE) systems. Users of modern NBE services expect not only h..

Classification of Escherichia coli K-12 ribosome binding sites. An error-control coding model

Though current computational methods have provided tools for locating start sites and increased the overall accuracy of gene locater systems such as GLIMMER and GeneMark, they usually require larger sequence windows for classification of initiation sites. Several initiation site classification tools such as RBSfinder use prior gene classification knowledge to aid in start site identification, hence functioning more like a postprocessor. The ribosome, the protein translation machine, makes initiation decisions based on &quot;real-time&quot; processing of a single messenger RNA leader region. To construct a classification system that can make sufficiently correct real-time classification decisions and use a relatively small classification window that is relatively independent of other environmental factors, we propose an approach based on information theory. Drawing on parallels between genetic information processing in living organisms and the processing of communications data, we develop an error-control coding-based translation initiation classification system that uses an eleven base classification window. In the sections that follow, we begin with an overview of channel codes and a summary of the translation initiation process. We draw parallels between the two and briefly review a channel code model for translation initiation. We present our block-code Bayesian classifier and discuss the results of applying our system to the translation start site location problem for Escherichia coli K-12. Channel Codes and Translation Initiation Overview of Channel Codes In data communication, the need for coding theory and its techniques stems from the need for error control mechanisms. In an engineering communication system, a k-symbol block (bits for a binary alphabet) of digitized information is encoded by a (n, k) encoder that combines the input symbols with (n-k) additional symbols based on a deterministic algorithm. In the biological domain a &quot;symbol&quot; can be the designator for an amino acid or nucleic acid base. The algorithm produces an (n, k) code, and the encoder is referred to as the channel encoder or the error-control encoder. The set of all valid n-symbol sequences (each sequence is called a codeword) produced by the (n, k) code make up the codebook The encoded information is transmitted through a potentially noisy channel where the transmitted bits can be corrupted in a random fashion. At the receiving end, the received message is decoded by a complementary channel decode

Workflow and End-User Quality of Service Issues in Web-Based Education

ABSTRACT: The option of obtaining education over networks is quickly becoming a reality for all those that have access to Internet and World-Wide Web (WWW). However, at present network-based education (NBE) over WWW, and over Internet in general, faces a number of pitfalls. The problems range from inadequate enduser quality of service (QoS), to inadequate materials, to lacks in learning paradigms, and missing or inappropriate student assessment and feedback mechanisms. In this paper we discuss some major issues that, although mostly solved for NBE, still face web-based education (WBE). This includes the required workfloworiented technological and quality of service support. In discussing the issues, we use examples from a wide-area NBE/WBE system called NovaNET and a WBE system called Web Lecture System (WLS). We recommend that WBE system developers construct operational user (workflow) profiles before building their content and interfaces. Our experience is that, especially for synchronous WBE systems, user-level round-trip keystroke delays should not exceed about 250 ms, and the overall availability of the system (including network-related service failures) should be at least 0.95. We also suggest that a successful WBE system will have a sound autoadaptive knowledge assessment component, a “virtual ” laboratory capability, and a set of strong collaborative functions. Until WBE systems match teacher/instructor and student workflows both technologically (as an appliance) and pedagogically, WBE, except in its most primitive form, will not be an effective educational tool. Contact Author

Speaker Independence in Automated Lip-sync for Audio-video Communication

By analyzing the absolute value of the Fourier transform of a speaker’s voice signal we can predict the position of the mouth for English vowel sounds. This is without the use of text, speech recognition or mechanical or other sensing devices attached to the speaker’s mouth. This capability can reduce the time required for mouth animation considerably. We expect it to be competitive eventually with the speech/text driven solutions which are becoming popular. Our technique would require much less interaction from the user and no knowledge of phonetic spelling. We discuss the problems of producing an algorithm that is speaker independent. The goal is to avoid having to measure mouth movements off video for each speaker’s training sounds. We have discovered that eliminating variation due to pitch yields moments which are mouth shape dependent but not speaker dependent. This implies that careful construction of predictor surfaces can produce speaker independent prediction of mouth motion for English vowels. Key words: facial animation, lip synchronization, speech processing. I