Remedial and second language English teaching using computer assisted learning

The problem addressed is that of teaching collegial and entering level university students the requisite skills to write intelligible papers and reports in English.This is a real problem in Montreal because a high proportion of the students have English as a second or third language in which their proficiency is limited or. though English may be their native language, their training in it is not adequate for the pursuit of further education.Several hundred students have worked through 20 or more CAL lessons each year for 3 years, and appreciable gains in skills have been measured. However, where it was possible to duplicate the CAL lessons as programmed texts, equal gains were achieved by those using the programmed texts.Current work is in two divergent directions: (i) providing simple template software for ESL and other teachers to write lessons; (ii) providing a measure of artificial intelligence and auto-adaptation, via a student-constructed sentence diagnosis and remediation package.A service and record system in CDC BASIC was produced to support the grammar lessons. However, a more powerful language is needed for the sentence diagnostician remediator. This was initially written in APL but used too much CPU time in that language and is now being re-written in NATAL (the Canadian standard CAL language).Three quasi-technical questions which also have paedogogical implications occurred and are answered: (i) To what extent can access procedures and frame formats (typography, etc.) be standardized for all studyware on the system? (ii) How: much data needs to be collected automatically to ensure that studyware is working properly and to identify needed improvements? (iii) To what extent should self-documentation of source-code be used, and to what extent should it be in a standardized format?Although a CAL language. CITCAN. was used initially on the CDC system, the level of expertise required to maintain it was too high, and subsequently the present system, written in BASIC, was developed. Personal computers, although available in this environment, are not as yet cost-effective when compared to time-shared access.We expect to move to a hybrid system, with studyware and records stored on the maxi-system. but actual “delivery” being provided by personal computers to which the studyware will be downloaded in blocks and from which the usage data will be collected back at sign-off.     

On the Implicit Anti-Aliasing Feature of Continuous-Time Cascaded Sigma–Delta Modulators

This paper deals with one of the most outstanding advantages of continuous-time (CT) sigma-delta modulators compared to their discrete-time counterparts: the implicit anti-aliasing feature (AAF). Although inherent in any CT architecture, analysis of anti-aliasing properties has mostly been restricted to single-stage modulators in the past. In this contribution, extensions on analysis methods for the study of the AAF of CT multistage noise-shaping architectures are covered. A theoretical model is introduced and confirmed through simulation results. Contrary to previous belief, the results indicate that usually all stages of a cascaded architecture are involved in the anti-aliasing behaviour and hence that it is not solely determined by the first stage.     

Human C-peptide. Part I: Radioimmunoassay

Synthetic human C-peptide bearing a Tyrosine group at its amino end is labelled with 125iodine using chloramin T or hydrogen peroxide and lactoperoxidase. The results are compared applying both methods. Antiserum to synthetic human C-peptide (without Tyrosine) which was partially compared to rabbit albumin, is raised in guinea pigs and goats. Goats show to be superior to guinea pigs concerning antibody production. The so-called "hook effect" phenomenon is observed in setting up the standard curves for the radioimmunoassay. Monotonically decreasing standard curves are obtained on dilution of antiserum with a high antibody titer which was produced by repeated immunization in goats. Free C-peptide and C-peptide bound to antiserum are separated with the anxion exchange resin Amberlite. Using this separation technique we excluded unspecific binding of labelled C-peptide to protein fractions in serum of diabetics. The sensitivity of our radioimmunoassay is approx. 0.3 ng C-peptide/ml serum. Intra- and interassay variability are below 10%. Human proinsulin is the only substance found to crossreact with the antiserum.     

The UCSC Kestrel parallel processor

The architectural landscape of high-performance computing stretches from superscalar uniprocessor to explicitly parallel systems, to dedicated hardware implementations of algorithms. Single-purpose hardware can achieve the highest performance and uniprocessors can be the most programmable. Between these extremes, programmable and reconfigurable architectures provide a wide range of choice in flexibility, programmability, computational density, and performance. The UCSC Kestrel parallel processor strives to attain single-purpose performance while maintaining user programmability. Kestrel is a single-instruction stream, multiple-data stream (SIMD) parallel processor with a 512-element linear array of 8-bit processing elements. The system design focuses on efficient high-throughput DNA and protein sequence analysis, but its programmability enables high performance on computational chemistry, image processing, machine learning, and other applications. The Kestrel system has had unexpected longevity in its utility due to a careful design and analysis process. Experience with the system leads to the conclusion that programmable SIMD architectures can excel in both programmability and performance. This work presents the architecture, implementation, applications, and observations of the Kestrel project at the University of California at Santa Cruz.     

Are fuzzy definitions of basic attributes of image objects reallyuseful?

Computer vision applications often involve measuring properties of objects in images. Typically, thresholding or segmentation techniques are used to obtain crisp object boundaries before object properties are computed. In this correspondence, we explore the possibility of using fuzzy definitions for measuring object properties without having to make crisp decisions about object boundaries prematurely. We present theorems which indicate that the use of fuzzy definitions to measure properties in intensity-based image analysis almost always gives accurate results. We also present experimental evidence and reasoning which show that fuzzy definitions are not always useful in feature-based methods     

Quantum Computer Development with Single Ion Implantation

Spins of single donor atoms are attractive candidates for large scale quantum information processing in silicon. Formation of devices with a few qubits is crucial for validation of basic ideas and development of a scalable architecture. We describe our development of a single ion implantation technique for placement of single atoms into device structures. Collimated highly charged ion beams are aligned with a scanning probe microscope. Enhanced secondary electron emission due tohigh ion charge states (e.g., ³¹P¹³⁺, or ¹²⁶Te³³⁺)allows efficient detection of single ion impacts. Studies of electrical activation of low dose, low energy implants of ³¹P in silicon show a drastic effect of dopant segregation to the SiO₂/Si interface,while Si₃N₄/Si retards ³¹P segregation. We discuss resolution limiting factors in ion placement, and process challenges forintegration of single atom arrays with control gates and single electron transistors. PACS: 03.67.Lx, 34.50.Dy, 85.35.Gv, 73.23, 61.72, 86.40.py, 07.79.-v     

Office task effects on comfort and body dynamics in five dynamic office chairs

In the present study, we investigated the effect of office tasks on posture and movements in field settings, and the comfort rating for chair characteristics and correlation with type of task. The tasks studied were: computer work, telephoning, desk work and conversation. Postures, movements, chair part inclinations and comfort rating data were collected from 12 subjects. Computer work showed the lowest physical activity, together with upright trunk and head position and low backrest inclination. Conversation shows the highest activity of head legs and low back together with the highest cervical spine extension. In contrast, desk work provoked the most cervical spine flexion and showed the second lowest activity. The telephoning tasks showed medium activity and the highest kyphosis. Conversation showed the highest backrest inclination. Positive comfort relations were found for computer work and a "swing system" chair, for telephoning and an active longitudinal seat rotation, and for desk work and a chair with a three-dimensionally moveable seat.