Showing papers on "Offset (computer science) published in 1972"

Optimal synchronization of traffic signal networks by dynamic programming

Abstract: THIS PAPER PRESENTS A SYNCHRONIZATION METHOD FOR DETERMINATION OF OPTIMAL OFFSETS IN ROAD TRAFFIC NETWORKS CONTROLLED BY FIXED-TIME SIGNALS. THE METHOD IS BASED ON DYNAMIC PROGRAMMING AND PROVIDES AN OPTIMAL SOLUTION, INDEPENDENT OF NETWORK LAYOUT, IN A FINITE NUMBER OF COMPUTATION STEPS. THE MATHEMATICAL MODEL OF THE SYNCHRONIZATION PROBLEM IS INTRODUCED FIRST. DEFINITIONS OF THE SYSTEM'S INDEPENDENT VARIABLES ARE GIVEN AND THE EQUATIONS CHARACTERIZING THE CONSTRAINTS IMPOSED ON THE OFFSET ACROSS-VARIABLES ARE FORMULATED. THE DEPENDENT VARIABLES OF THE SYSTEM ARE THE COST FUNCTIONS ASSOCIATED WITH EACH LINK OF THE TRAFFIC NETWORK. THE OPTIMIZATION TARGET IS A MINIMIZED ECONOMIC OBJECTIVE FUNCTION COMPRISING THE INDIVIDUAL LINK FUNCTIONS AND POSSIBLY IN- CLUDING DELAY TIMES AS WELL AS STOPS. THE PROBLEM IS NONLIN- EAR (OWING TO THE CHARACTER OF THE LINK COST FUNCTIONS) AND CONTAINS INTEGER VARIABLES IN THE CIRCUIT CONSTRAINT EQUA- TIONS. THE ALGORITHM FOR ITS SOLUTION IS BASED ON PARTIAL MINIMIZATIONS CONCLUDED BY DETERMINING A FUNDAMENTAL SET OF OPTIMAL OFFSETS AS WELL AS THE OPTIMAL VALUE OF THE OBJECT- IVE FUNCTION. IN ORDER TO OVERCOME THE "CURSE OF DIMENSION- ALITY" INHERENT IN MULTIVARIABLE PROBLEMS, A DECISION-TREE ALGORITHM IS EMPLOYED FOR OBTAINING A MINIMIZATION PLAN WHICH IS OPTIMAL IN TERMS OF THE COMPUTATIONAL EFFORT INVESTED. THE AIM, IN THIS CASE, IS TO MINIMIZE THE REQUIRED COMPUTER STORAGE CAPACITY AND NUMBER OF OPERATIONS.

Universal joint with flexibly connected offset cross pins

Abstract: An offset cross pin universal joint has a flexible coupling connecting the cross pins which permits lateral shifting of the cross pin axis during joint rotation.

Offset signal correction system

Abstract: A system for correcting offset in analog signal generator output is responsive to simple pulse signal request for correction. A bistable circuit is set upon receiving the correction request and thereupon enables a coincidence circuit to gate pulses to a counter. The counter output is converted by a digital-to-analog converter whose output signal is combined subtractively with the offset signal. Upon nulling of the offset signal the bistable circuit is reset.

On-line feedback control of offsets for area control of traffic

Abstract: THE THEORY AND THE METHOD OF ON-LINE FEEDBACK CONTROL OF SIGNAL OFFSETS FOR COMPUTERIZED AREA CONTROL OF TRAFFIC ARE PRESENTED IN THIS PAPER BASED ON THE DATA OBSERVED IN THE AREA TRAFFIC CONTROL SYSTEM IN DOWNTOWN TOKYO. IN THIS METHOD, OFFSETS ARE ALWAYS GRADUALLY AND CONTINUALLY SHIFTED SO THAT DELAY IS REDUCED AND, THEREFORE, IT IS NO LONGER NECESSARY TO SWITCH OFFSET PATTERNS FROM ONE TO ANOTHER DISCONTINUOUSLY WHICH IS INEVITABLE IN CONVENTIONAL OFFSET PATTERN SELECTION CONTROL. THE METHOD IS APPLICABLE WITHOUT NECESSITATING EXTRA HARDWARE, BECAUSE THE HARDWARE NECESSARY FOR THE METHOD IS ONLY A DETECTOR ON AN APPROACH. EXPERIENCES IN THE TOKYO AREA CONTROL SYSTEM INDICATE THAT THE METHOD WORKS WELL AND IS FEASIBLE FOR THE PRACTICAL USE.

True distance to way point and offset computer

Abstract: Navigation equipment provides AC signals proportional to X and Y coordinates of an aircraft with respect to a selected way point which are applied to opposite ends of a series RC circuit, the center of which is used as an input to a triangle solving means, as is an offset indicating signal (designating the amount by which a parallel track to be flown is offset from the track to the way point) to provide a true distance to way point signal. When the offset amount is zero, true distance to way point is still achieved. True distance to way point without offset is provided by synchronously demodulating the center tap of the R/C circuit. True distance to way point is provided even when flying in a circle, or when flying a track which is offset from and parallel to a previously established track to a way point.

Ultrasonic-gaging system method and apparatus

Abstract: A method and apparatus for measuring a time interval. In particular an ultrasonic-gaging system for measuring the thickness of an object by generating an absolute analog signal defining the difference between a dummy measurement and a full measurement. During the dummy measurement, a digitally controlled current related to the material velocity coefficient of the object charges an integrator capacitor for a first time interval. Upon completion of the dummy measurement, the voltage stored on the integrator capacitor is applied to an offset capacitor through an amplifier. The offset capacitor is charged to a first voltage which represents the dummy measurement interval and system errors. During the full measurement, the integrator capacitor, which is discharged at the begining of the full measurement, is charged by the material velocity coefficient current for a second time interval related to the thickness of the object plus the interval of the dummy measurement, the second time interval greater than the first time interval. Upon completion of the full measurement, the voltage stored on the integrator capacitor is fed to a digital panel meter via the amplifier and offset capacitor. The signal at an output terminal of the amplifier represents the thickness of the object plus the interval of the dummy measurement and system errors. The absolute analog signal applied to the panel meter is the difference between the signals at the output terminal of the amplifier at the end of the dummy full measurements, the first voltage being stored on the offset capacitor.

Magnetic thin film shift register having bidirectional transmission elements and offset block sites

Abstract: A digital shift register propagating information as discrete regions of reverse magnetization has a bidirectional transmission path and has means for producing magnetic fields both continuously along the transmission path and only at selected sites along the path. Domain-blocking fields are produced at sites along the path offset uniformly from domain-holding locations by less than one-half the spacing between adjacent hold locations. In each domain-propagating step, the block fields are produced offset from the propagate fields by a time corresponding to the spatial offset.

Offset breakwater configuration

Abstract: Motion of a structure subject to the forces of impinging waves is substantially decreased and the transmission of wave motion past such structure accordingly diminished by providing the structure with a plurality of wave reflecting surfaces alternatingly offset from each other by a distance approximating one-half the wavelength of the impinging waves.

Radio navigation beacon

Abstract: A Doppler Navigation system which includes a surface based commutated array on a platform to provide air derived angle information, particularly for aircraft landing approach guidance. The program of array commutation is frequency off-set with respect to a reference antenna and this offset is used in the air derivation of angle data. A gyro or other source of platform pitch or yaw provides a signal which is used to shift the so-called offset to compensate measurement errors due to platform motion.

Multiplier offset voltages in adaptive arrays

Abstract: This paper examines the effects of multiplier offset voltages in adaptive arrays. Multiplier offset voltages arise when active circuits are used to implement the error-by-signal multipliers required in an array based on the LMS algorithm. These offset voltages are known from experimental work to have a strong effect on array performance. First, it is shown how multiplier offset voltages may be included in the differential equations for the array weights. Then their effect on weight behavior is studied. It is found that the offset voltages affect the final values of the weights, but not the time constants. How much effect they have is influenced by the amount of element noise in the array. An adequate amount of noise is necessary to minimize weight errors due to offset voltages. An example is treated to show the effect of offset voltages on the final array weights and the output SNR. With offset voltages present, it is found that there is a maximum SNR that can be obtained from the array. A specific input SNR is required to obtain this maximum output SNR. Finally, it is shown that a finite operating range for the weights places a further restriction oh the acceptable values of offset voltages and noise.

Tool offset means for tracer mechanisms

Abstract: A tracer valve for controlling a machine tool for duplicating on a workpiece the contour of a template or pattern. For a given tool setup, the offset of the stylus from the tracer valve sensor is known and geometry, for in the system's geometry. including the geometry of the tools being used. However, when a different machining operation is to be performed, or when a new tool is used for a second operation of the same kind, the offset must often be changed. This invention provides a means for pre-setting and for changing tool offsets in order that sequential operations can be carried out without changing the template and even without changing the tool for a given setup. It includes a stylus support having three pivoted links and four pivots, one pivot being a joinder with the tracer sensor whereby the latter is semi-fixed in space and acts as a fulcrum in determining the offset of the stylus tip from the tracer sensor.