Showing papers by "Ryerson University published in 1996"
Posted Content•
TL;DR: The authors employed response surface regressions based on simulation experments to calculate asymptotic distribution functions for the likelihood ratio tests for cointegration proposed by Johansen and provided tables of critical values that are very much more accurate than those available previously.
Abstract: This paper employs response surface regressions based on simulation experments to calculate asymptotic distribution functions for the likelihood ratio tests for cointegration proposed by Johansen The paper provides tables of critical values that are very much more accurate than those available previously However the principal contributions of the paper are a set of data les that contain estimated asymptotic quantiles obtained from response surface estimation and a computer program for utilizing them This program which is freely available via the Internet can easily be used to calculate asymptotic critical values and P values Graphs of some of the tabulated distribution functions are also provided An empirical example motivated by the European Economic and Monetary Union proposed in the Maastricht Treaty suggests that not all the countries of the European Union may qualify initially for participation in the EMU.
1,841 citations
TL;DR: Community-level characterization of microbial biomass from a municipal activated sludge plant, and two bleached kraft mill effluent treatment systems, and an aerated lagoon system, was carried out using the BIOLOG redox-based carbon-substrate utilization assay, suggesting a unique indigenous microbial population in each system.
80 citations
TL;DR: In this article, the authors compared energy and exergy analyses of a wide range of hydrogen production processes, including processes which are hydrocarbon-based (steam-methane reforming and coal gasification), non-hydrocarbon based (water electrolysis and thermochemical water decomposition) and integrated (steam mithane reforming linked to the nonhydro carbon-based processes).
76 citations
Journal Article•
TL;DR: In this article, a study was conducted to examine the factors that influence student and registered nurse attitudes toward computers, including nurses' work, barriers, organizational issues, and barriers to use.
Abstract: A study was undertaken to examine the factors that influence student and registered nurse attitudes toward computers. This article provides a report of the psychometric findings related to the use of Stronge and Brodt's Nurses' Attitudes Toward Computerization questionnaire. The convenience sample consisted of 394 registered nurses employed in a large metropolitan hospital and 299 baccalaureate student nurses. Principal component analysis was performed identifying three factors for the nurse sample, including nurses' work, organizational issues, and barriers to use. Four factors emerged in the student sample: nurses' work, barriers, organizational issues, and efficiency issues. These findings were inconsistent with previous studies and the underlying categories identified by Stronge and Brodt. Further development of the understanding of the substantive components of attitudes toward computers is recommended.
47 citations
TL;DR: An ensemble of unknowns comprises a solution to the classical ''structure-and-motion from optic flow'' problem by utilizing a method for interpreting the bilinear image velocity equation by solving simple systems of linear equations.
45 citations
TL;DR: In this article, the authors compared energy and exergy analyses of production processes for hydrogen, ammonia and methanol from natural gas, and found that energy losses associated with emissions account for 100% of the total energy losses.
30 citations
TL;DR: HRV and BPV provide clear evidence of impaired sympathetic and parasympathetic autonomic nervous system response to tilt with autonomic failure, and the similarity in signal complexity with reduced fractal and harmonic spectral power, in patients compared with controls, suggests unchanged cardiovascular neural input and integration with reduced output in autonomic failures.
Abstract: We examined heart rate and blood pressure variability (HRV and BPV) during graded tilt (5 min in each position: supine, -10 degrees, 10 degrees, 30 degrees, 60 degrees, -10 degrees, supine) in auto...
26 citations
21 citations
TL;DR: In this article, an analysis of response strategies employed by 300 first year undergraduate students on a chemistry test to answer questions posed in multiple choice and constructed response formats was performed. But, the results showed no significant differences in the types of solution strategies employed, nor in the type of errors committed, across test format.
Abstract: This paper reports an analysis of response strategies employed by 300 first year undergraduate students on a chemistry test to answer questions posed in multiple choice and constructed response formats. Test answers were categorized and analyzed for format-related differences in solution strategies and error patterns. A subgroup of 21 students who had written the test were interviewed following the test with the intent of further exploring the response strategies which they had used. The verbal reports from the interviews were scored for the presence of typical problem-solving behaviours. Analysis of the test data indicated no significant differences in the types of solution strategies employed, nor in the types of errors committed, across test format. Most students used algorithmic production strategies and “worked out” the answers without regard to question format. However, the verbal data revealed evidence of subtler differences in the types and frequencies of problem-solving behaviours, particularly with respect to problem representation and answer evaluation.
17 citations
23 Jun 1996
TL;DR: In this paper, the authors proposed the characterization of the GTO and the snubber components by formulation of the current-source inverter equivalent circuit during the device commutation period, thereby obtaining accurate voltage and current waveforms of the GTO and associated snubbers.
Abstract: The pulsewidth-modulated (PWM) current-source inverter (CSI) used in AC motor drive applications can be implemented with symmetric gate turn-off thyristors (GTOs). One of the major difficulties in the optimization of the GTO switch and the snubber components of the inverter is the variation in different switching conditions encountered during normal operation. Past work has concentrated on the GTO and snubber components in voltage-source applications, where commutation of the GTO device is an independent process and does not affect the operation of the other inverter devices. This paper proposes the characterization of the GTO and the snubber components by formulation of the CSI equivalent circuit during the device commutation period. From the equivalent circuit, the state equations are derived, thereby obtaining accurate voltage and current waveforms of the GTO and associated snubbers. From the analysis, the component power loss can be calculated and optimization performed. Simulation results are verified by using both a laboratory prototype and medium-voltage drive system.
16 citations
TL;DR: In this article, the authors used agarose to stabilize microbial flocs from activated sludge and found that it is compatible with SCLM and TEM techniques and minimized perturbations.
TL;DR: This paper presents a new equilibrium-seeking algorithm, called the decoupling algorithm, for calculation of multiperiod equilibrium of supplies and demands when demand has a geometric distributed lag GDL structure and supply is represented by a linear process submodel.
Abstract: This paper presents a new equilibrium-seeking algorithm, called the decoupling algorithm, for calculation of multiperiod equilibrium of supplies and demands when demand has a geometric distributed lag GDL structure and supply is represented by a linear process submodel. The new algorithm is required because it may be difficult to obtain the equilibrium by a diagonalization algorithm such as PIES. In each step of the decoupling algorithm, a modified GDL equilibrium model, the "decoupled submodel," is solved by the PIES algorithm; successive approximations move closer to the true equilibrium. Two versions of a large-scale realistic model of North American energy supplies and demands are solved with the decoupling algorithm to aid in understanding the behavior of the decoupling algorithm.
TL;DR: In this article, a commercial process-simulation computer code, previously enhanced by the author for exergy analysis, is used in the analyses of a wide range of production processes for hydrogen and hydrogen-derived fuels.
26 May 1996
TL;DR: In this article, a unique PWM switching pattern and a novel power factor control scheme for high power GTO AC/DC converters are presented, which achieves 5th and 7th harmonic elimination and an adjustable DC output current simultaneously.
Abstract: This paper presents a unique PWM switching pattern and a novel power factor control scheme for high power GTO AC/DC converters. This switching pattern has a switching frequency of 360 Hz, which is the lowest possible frequency to achieve 5th and 7th harmonic elimination and an adjustable DC output current simultaneously. Using both feedback and feedforward control techniques, the proposed power factor control scheme can keep the converter input power factor at unity or a maximum achievable value. Simulation and experimental results are given to confirm the proposed PWM pattern and power factor control scheme.
TL;DR: It was found that non-heat-treated products made on- site at small deli-type establishments were more likely to be left constantly unrefrigerated than those made off-site at larger commercial plants, which is suggested that larger commercial establishments may recognize the value of lowering the pH and aw and have equipment for such measurements.
TL;DR: In this article, the authors investigated the environmental and health benefits of using heat cogenerated from the facilities of the main provincial electrical utility, Ontario Hydro, to drive absorption chillers which supply the cooling needs of district cooling networks in the province of Ontario.
TL;DR: Clients who attended a brief number of sessions reported no significant difference in satisfaction with the counselling compared to those who attended more sessions, and counsellors were less satisfied overall with the briefer counselling process, and the author suggests that they were biased against it.
Abstract: After termination of personal counselling at a large urban Canadian university, 72 subjects and their counsellors were asked to rate their satisfaction. The subjects were asked to rate to what extent the counselling had helped with the presenting problem, and with other secondary problems, and to rate their degree of overall satisfaction. Statistical analyses conducted to investigate the relationship among number of sessions attended and client and counsellor satisfaction, led to these results: clients who attended a brief number of sessions (1-3) reported no significant difference in satisfaction with the counselling compared to those who attended more sessions; and the majority of clients who had only one session were satisfied with their counselling; counsellors, however, were less satisfied overall with the briefer counselling process, and the author suggests that they were biased against it. The author recommends more research on this critical topic of counsellor expectations toward briefer ...
TL;DR: In this article, a multidimensional finite-difference model based on the Advection-Dispersion equation was used to predict migration of the contaminants in a natural marshland system.
TL;DR: It is concluded that these arguments fail to show that competent wishes could justifiably be overturned, and it remains an open question whether accounts of decision-making capacity based solely on the notions of understanding and appreciation can adequately deal with various complexities.
Abstract: The authors examine recent arguments purporting to show that mental incompetence (lack of decision-making capacity) is not a necessary condition for intervention in a person's best interests without consent. It is concluded that these arguments fail to show that competent wishes could justifiably be overturned. Nonetheless, it remains an open question whether accounts of decision-making capacity based solely on the notion of understanding and appreciation can adequately deal with various complexities. Different possible ways of resolving these complexities are outlined, all of which need further exploration.
TL;DR: An efficient and computationally simple CFAR detection procedure is proposed, based on the comparison of the covariance structure of the data vector under test with that of the interference, and shown that for interference with moderate and high autocorrelation, the new test provides about 6 to 12 dB improvement over the conventional normalization technique.
TL;DR: In this paper, a location-allocation approach for the negotiation of comprehensive land claim agreements has been proposed, with the added constraint that the methodology should be transparent and easily understood at the community level.
TL;DR: In this paper, the safety effect of a freeway traffic management system (FTMS) implemented on a segment of Highway 401 in Toronto, Canada was estimated from the parameters of regression models calibrated for the pre-implementation period (1989-1990) and the post-initiative period (1991-1992) for express, collector, and conventional divided roadway sections and for rear-end, non-rear-end and all injury accidents.
Abstract: A reduction in accidents, particularly secondary ones, is often cited as one of the primary benefits of a freeway traffic management system (FTMS) such as that implemented on a segment of Highway 401 in Toronto, Canada. The safety effect of this FTMS was estimated from the parameters of regression models calibrated for the preimplementation period (1989-1990) and the postimplementation period (1991-1992). Separate models were calibrated for express, collector, and conventional divided roadway sections and for rear-end, non-rear-end, and all injury accidents. For rear-end injury accidents, model parameters were estimated for day and night conditions. The aggregate results show a substantial decrease in the expected number of rear-end injury accidents on all three types of roadway following the implementation of the FTMS.
TL;DR: In this paper, the authors solved steady, laminar, two-dimensional, conjugate natural convection in a rectangular enclosure numerically using finite element methods and obtained data Pr = 0.7 over a Rayleigh number range (based on the enclosure width) of 0 ≤ Ra ≤ 106.
Abstract: Solves steady, laminar, two‐dimensional, conjugate natural convection in
an rectangular enclosure numerically. The enclosure consists of heated and
cooled isothermal walls connected by either adiabatic or perfectly conducting
end walls. The enclosure is partially filled with a finitely conducting
non‐porous thermal insulation, adjacent to the heated surface. Solves the
governing equations (in stream function‐vorticity form) using a finite
element method. Obtains data Pr = 0.7 over a Rayleigh number range (based on
the enclosure width) of 0 ≤ Ra ≤ 106. The results show the
effect of solid insulation thickness on the average Nusselt number for a
range of enclosure aspect ratios, inclination angles and solid‐to‐fluid
conductivity ratios. Aims to determine the conditions that produce the
minimum overall heat transfer rate.
TL;DR: In this article, an interactive program to evaluate the nuclear symplectic representations associated with a nucleus of mass number A is presented. The code is in C language and is based on an algorithm developed by one of the authors (MJC).
Proceedings Article•
12 Nov 1996TL;DR: WatIF is described, a simple compiler intermediate form based on the λ-calculus, for writing compiler front-ends for a wide range of programming languages, showing the large set of application-language features supported by WatIF.
Abstract: This paper describes the use of WatIF, a simple compiler intermediate form based on the λ-calculus, for writing compiler front-ends for a wide range of programming languages Somewhat similar intermediate forms have been previously used for single-language compilers, but applicability to such a range of languages has not been previously reported Examples of code generated by front-ends for several languages show the large set of application-language features supported by WatIF
Journal Article•