Showing papers by "Ontario Ministry of Transportation published in 1976"
29 Jan 1976
TL;DR: In this article, a technique to resolve the incident and reflected waves from the records of composite waves is presented, which is applicable to both regular and irregular trains of waves and is effective in the range outside the condition of the gauge spacing being even integer of half wavelength.
Abstract: A technique to resolve the incident and reflected waves from the records of composite waves is presented. It is applicable to both regular and irregular trains of waves. Two simultaneous wave records are taken at adjacent locations, and all the amplitudes of Fourier components are analyzed by the FFT technique. The amplitudes of incident and reflected wave components are estimated from the Fourier components, and the incident and reflected wave spectra are constructed by smoothing the estimated periodograms. The wave resolution is effective in the range outside the condition of the gauge spacing being even integer of half wavelength. The ratio of incident and reflected wave energies in the effective resolution range is employed in estimating the overall reflection coefficient. The incident and reflected wave heights are estimated from the composite wave heights by energy consideration.
731 citations
TL;DR: A finite element solution based on the Galerkin method was developed for the Saint-Venant equations that approximately govern unsteady flow in rigid open channels as discussed by the authors, and applications to test problems confirmed stability provided that time steps were not so large as to render invalid the Newton linearization scheme used for the friction factor.
Abstract: A finite element solution based on the Galerkin method was developed for the Saint-Venant equations that approximately govern unsteady flow in rigid open channels. A predictor-corrector solution scheme produced theoretically stable and convergent results, and applications to test problems confirmed stability provided that time steps were not so large as to render invalid the Newton linearization scheme used for the friction factor. Linear elements were adequate for all problems solved. Time step limitations to produce accurate results were closely related to: (1) The degree to which piecewise linear functions describing the variation of depth and discharge in time could be fit to the actual curvilinear functions; and (2) the value given to the time step weighting factor. Values of this factor near 0.5 gave the best results.
76 citations
TL;DR: This paper is a final report on the driving and psychomotor tracking studies conducted by the Canadian Commission of Inquiry into the Non-Medical Use of Drugs (LeDain Commission).
Abstract: This paper is a final report on the driving and psychomotor tracking studies conducted by the Canadian Commission of Inquiry into the Non-Medical Use of Drugs (LeDain Commission). Preliminary reports of these studies appeared in the commission’s cannabis report.2s The effects of cannabis on psychomotor performance have been studied for a variety of psychomotor tasks, including skills involved in automobile driving l2 and simulated driving.*% R, 16, 22 Psychomotor abilities that have been shown to be impaired by cannabis under certain conditions include pursuit tracking a c c ~ r a c y , ~ ~ 12. 13, 18, 26 hand and body ~teadiness,~, 9 , braking stop time,l*. l6 and start time.16 Other abilities that are of likely importance in the complex skill of automobile driving that also have been shown to be adversely affected by cannabis at certain doses are short-term memory,I5 vigilance and signal detection,30. 23 and performance on divided attention tasks.* Additional areas of interest regarding driving ability and traffic safety and possible adverse or beneficial effects due to cannabis include judgmental faculties, such as the perception of danger, driver attitudes, risk taking, susceptibility to distraction or stress, and experience in driving while “high,” that is, statedependent learning.’, 10. 2’ The effects of cannabis on psychomotor abilities have frequently been shown to be related to dosage. At low dosages, effects are generally not observed, but with larger dosages, effects become apparent and progressively larger with increased d o ~ a g e . ~ The dosage relationship is complicated by the finding that
58 citations
TL;DR: In this article, a trajectory sensitivity approach is taken to the design of a Kalman filter for a system with uncertain parameters, where the performance index depends on the variances of the parameter deviations.
Abstract: A trajectory sensitivity approach is taken to the design of a Kalman filter for a system with uncertain parameters. A two-point boundary value problem (TPBVP) is formulated, where the performance index depends on the variances of the parameter deviations. A suboptimal algorithm is also developed. An example shows that estimation errors may be reduced considerably from those generated by a Kalman filter design for the nominal parameter values.
30 citations
TL;DR: In this paper, a previously developed method for computing the progressive rise of pore pressures in saturated sands subjected to cyclic loading has been adjusted to fit data obtained from triaxial torsion tests.
17 citations
TL;DR: In this paper, an experimental study of a single span horizontally curved plexiglass box-girder beam with diaphragms and flange overhangs is presented.
Abstract: This paper describes an experimental study of a single span horizontally curved plexiglass box-girder beam with diaphragms and flange overhangs. Static loads were applied at midspan to cause a complex pattern of membrane and bending stresses with the effects of diaphragms clearly evident. Experimental results in typical cases are shown graphically and compared to the results of a special purpose finite element program developed especially for curved box analysis. Good agreement between experimental and analytical results were obtained.
16 citations
TL;DR: In this paper, the authors compare measured and theoretical values of the horizontal force calculated by different methods and conclude that a failure mode transitional between that of crushing and flexure occurs for the steeper cone angles.
6 citations
TL;DR: Algorithms for reliability modeling of multistate large repairable systems consisting of several units, each contributing a finite amount to the total system capacity are proposed.
5 citations
TL;DR: The test II (antiantiglobulin variant) proved to be positive in 88 cases of autoimmune haemolytic anaemia (AIHA) that showed a negative direct Coombs' test and a negative antiglOBulin variant.
Abstract: . An aggregate-haemagglutination test has been used for determining antierythrocyte autoantibodies. The first antiglobulin variant of the test allows us to establish the presence of antibodies in 33 cases with a negative direct Coombs' test. The test II (antiantiglobulin variant) proved to be positive in 88 cases of autoimmune haemolytic anaemia (AIHA) that showed a negative direct Coombs' test and a negative antiglobulin variant. Immunoglobulin G has been revealed in the majority of AIHA patients. IgM has been determined in 1 case of a symptomatic form associated with chronic lymphocytic leukaemia. IgA has been recorded in 3 cases with an idiopathic AIHA form and in 6 cases of chronic lymphocytic leukaemia. Both types of light chains were found on the surface of erythrocytes in all cases of AIHA.
4 citations
TL;DR: In this article, an additive term is presented to correct the energy sum based noise indices for lateral flight path dispersion, and the correction term depends only on the horizontal and vertical distances between the observer and the closest point on the mean flight path, both distances being normalized by the standard deviation of the lateral fluctuations.
3 citations
TL;DR: In this article, existing knowledge on speech interference, community annoyance, hearing hazard and sleep disturbance is reviewed in order to suggest criteria for the wayside noise from trains, it being borne in mind that the sound is intermittent and its points of reception may be indoors or outdoors.
11 Jul 1976
TL;DR: In this paper, the authors investigated the ability of subject drivers to perform a two-lane passing task, with oncoming traffic, as a function of the level of ambient illumination and the headlight intensity of the oncoming vehicle.
Abstract: The experiment investigated the ability of subject drivers to perform a two-lane passing task, with oncoming traffic, as a function of the level of ambient illumination and the headlight intensity of the oncoming vehicle.Eight experienced drivers performed both passing trials and gap-estimation trials, under closed-course conditions, during dawn and dusk hours. Levels of ambient illumination varied from approximately .02 to 200 foot candles during the experiments. Headlight conditions included no lights, normal low-beam headlights and low-beams with filters which reduced their intensity to about 1/3 of normal.Results indicated that the gaps accepted by drivers in a two-lane passing situation increased with an increase in the intensity of the headlight of the oncoming vehicle. The range of gaps accepted across headlight conditions was smaller, however, at higher levels of ambient illumination than at lower levels. Best results in terms of mean gaps accepted and minimum variability in performance was achiev...
29 Jan 1976
TL;DR: In this paper, the authors present some general properties on topographic change on the shore and sea bed in the vicinity of ports and harbours constructed on the sandy beach, mainly with the case study of Kashima Port.
Abstract: This paper presents some general properties on topographic change on the shore and sea bed in the vicinity of ports and harbours constructed on the sandy beach, mainly with the case study of Kashima Port. Following three characteristics of the topographic change due to prolongation of breakwaters are discussed; that is, i ) The shoaling and the change of topography in the area surrounded by breakwaters and shoreline, ii ) Topographic change of artificial beach in the updrift beach of breakwater having the long oblique part, iii. ) Erosion and accretion of downdrift beach due to the prolongation of the oblique part of breakwater.
TL;DR: In this paper, a 1/4.80 scale direct model study conducted on the negative moment region of the proposed structure is presented, particular emphasis being placed on the interface section between the precast girders and the in-situ concrete pier cap.
Abstract: In a recent report to the Ontario Precast Concrete Manufacturers Association, a firm of consulting engineers recommended the adoption of a new standard precast concrete trapezoidal box section bridge girder. This section is intended to replace standard I-section girders in spans of 100ft-150ft (30.5m to 45.8 m); and is being used for the first time in a proposed two-span continuous underpass structure. A 1/4.80 scale direct model study conducted on the negative moment region of the proposed structure is presented in this paper, particular emphasis being placed on the interface section between the precast girders and the in-situ concrete pier cap. Modeling criteria, materials, techniques and certain distortions allowed in the study are examined. Based on the study, a recommendation was made for the reduction of 11% in the level of longitudinal post-tensioning. Satisfactory performance of the prototype interface and pier cap sections can be expected under working and ultimate load conditions.
Journal Article•
TL;DR: There has been comparatively little study of train noise acceptability, but state-of-the-art knowledge is reviewed, and criteria in terms of Leq.
Abstract: There has been comparatively little study of train noise acceptability. This paper reviews state-of-the-art knowledge on the subject, and suggests criteria in terms of Leq.