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Showing papers by "General Electric published in 1986"


Journal Article
TL;DR: The Leader as Social Architect I: Making Bureaucracy Behave as mentioned in this paper : Motivating people to change the way they behave. The Leader as social Architect II: Motivating People.
Abstract: The Themes, The Protagonists, The Transformational Drama. RECOGNIZING THE NEED FOR REVITALIZATION. The Gathering Storm. Overcoming the Resistance to Change. CREATING A NEW VISION. Diagnosing the Problem. Creating a Motivating Vision. Mobilizing Commitment: Getting People Signed on to the Mission. INSTITUTIONALIZING CHANGE. Creative Destruction: Reweaving the Social Fabric. The Leader as Social Architect I: Making Bureaucracy Behave. The Leader as Social Architect II: Motivating People. EPILOGUE. History Repeats Itself. Notes. References. Index.

1,091 citations


Journal ArticleDOI
TL;DR: In this article, a basic feedforward algorithm for executing this type of current vector torque control is discussed, including the implications of current regulator saturation at high speeds, and the key results are illustrated using a combination of simulation and prototype IPM drive measurements.
Abstract: Interior permanent-magnet (IPM) synchronous motors possess special features for adjustable-speed operation which distinguish them from other classes of ac machines. They are robust high powerdensity machines capable of operating at high motor and inverter efficiencies over wide speed ranges, including considerable ranges of constant-power operation. The magnet cost is minimized by the low magnet weight requirements of the IPM design. The impact of the buried-magnet configuration on the motor's electromagnetic characteristics is discussed. The rotor magnetic circuit saliency preferentially increases the quadrature-axis inductance and introduces a reluctance torque term into the IPM motor's torque equation. The electrical excitation requirements for the IPM synchronous motor are also discussed. The control of the sinusoidal phase currents in magnitude and phase angle with respect to the rotor orientation provides a means for achieving smooth responsive torque control. A basic feedforward algorithm for executing this type of current vector torque control is discussed, including the implications of current regulator saturation at high speeds. The key results are illustrated using a combination of simulation and prototype IPM drive measurements.

853 citations


Journal ArticleDOI
TL;DR: The intrinsic and system SNR is applied to predict image SNR and has found satisfactory agreement with measurements on images, which indicates that the initial choice of pixel size is crucial in NMR.
Abstract: The fundamental limit for NMR imaging is set by an intrinsic signal-to-noise ratio (SNR) for a particular combination of rf antenna and imaging subjects. The intrinsic SNR is the signal from a small volume of material in the sample competing with electrical noise from thermally generated, random noise currents in the sample. The intrinsic SNR has been measured for a number of antenna-body section combinations at several different values of the static magnetic field and is proportional to B0. We have applied the intrinsic and system SNR to predict image SNR and have found satisfactory agreement with measurements on images. The relationship between SNR and pixel size is quite different in NMR than it is with imaging modalities using ionizing radiation, and indicates that the initial choice of pixel size is crucial in NMR. The analog of "contrast-detail-dose" plots for ionizing radiation imaging modalities is the "contrast-detail-time" plot in NMR, which should prove useful in choosing a suitable pixel array to visualize a particular anatomical detail for a given NMR receiving antenna.

760 citations


Journal ArticleDOI
TL;DR: A novel method for modeling swept voume by computing a family of critical curves from a moving solid is presented, developed for real-time verification of NC tool paths using computer graphics.
Abstract: The modeling of swept volume is important in simulating the interference between a moving solid and its environment. This article presents a novel method for modeling swept voume by computing a family of critical curves from a moving solid. Based on this approach, a system has been developed for real-time verification of NC tool paths using computer graphics.

373 citations


Patent
26 Sep 1986
TL;DR: In this article, a multichip integrated circuit package comprises a substrate (10) to which is affixed one or more integrated circuit chips (15a, 15b, 15c) having interconnection pads (16).
Abstract: A multichip integrated circuit package comprises a substrate (10) to which is affixed one or more integrated circuit chips (15a, 15b, 15c) having interconnection pads (16). A polymer film (20) overlying and bridging integrated circuit chips present is provided with a plurality of via openings to accommodate a layer of interconnection metallization (25) which serves to connect various chips and chip pads within the interconnection pads disposed on the chips. A significant advantage of the packaging method and configuration of the present invention is the ability for the polymer film to be removed. This significantly improves testability and effectively provides wafer scale integration circuit packages which are free of problems associated with yield and testability.

324 citations


Journal ArticleDOI
H.D. Solomon1
TL;DR: In this paper, a model is presented which describes the influence of plastic strain and cycling frequency and temperature changes on fatigue life, which account for temperature changes, cycling waveshape, and joint geometries.
Abstract: Plastic strain versus fatigue life data are presented for tests run at -- 50, 35, 125, and 150°C. It was found that these data could be correlated by the Coffin-Manson fatigue law, with an exponent of approximately 0.5 for the tests run at -35°C to 125°C. At 150°C the exponent was reduced to 0.37. These results were obtained for plastic strain limited tests. Different results are obtained when total strain limits are employed. This difference is discussed. The influence of cycling frequency and temperature changes are also discussed. A model is presented which describes the influence of plastic strain and cycling frequency. Corrections to the model predicted fatigue life, which account for temperature changes, cycling waveshape, and joint geometries, are also discussed.

310 citations


Journal ArticleDOI
TL;DR: An Industry Assessment Study (IAS) was conducted to evaluate the present reliability of powerhouse motors and to identify design and operational characteristics which, through advanced development, offer the potential of increased motor, and therefore, power plant reliability.
Abstract: An Industry Assessment Study (IAS) was conducted to evaluate the present reliability of powerhouse motors and to identify design and operational characteristics which, through advanced development, offer the potential of increased motor, and therefore, power plant reliability. The primary objective of the IAS was to collect, analyze, and interpret candid, detailed information concerning motor application, operating factors, installation, manufacturer, failures and causes of failures. The survey data covers 6312 motors from 168 generating units representing 65 utilities. This data covers 40 percent of the population surveyed. The large quantity of data allows a meaningful analysis when it is broken down into smaller groupings.

287 citations


Journal ArticleDOI
Jerry M. Mendel1

285 citations


Journal ArticleDOI
TL;DR: A method is described here that allows observation of the dynamical aspects of cultured cells and their presence and their motion are directly reflected in the measured impedance.
Abstract: Mammalian cells can be cultured and therefore studied in vitro. Normally, the cells' morphology and other static properties are observed with the aid of a light microscope. A method is described here that allows observation of the dynamical aspects of cultured cells. Mammalian fibroblasts are cultured in polystyrene dishes that contain evaporated gold electrodes. As the cells attach to the electrodes, their presence and their motion is directly reflected in the measured impedance.

278 citations


Journal ArticleDOI
TL;DR: It is apparent that aerobic bacteria can degrade a broader spectrum of PCB congeners than previously believed and that this broad spectrum of degradative competence can exist in a single strain.
Abstract: Congeners of polychlorinated biphenyl (PCB) differ in the number and position of chlorine substituents. Although PCBs are degraded, those congoners with five or more chlorines have been considered resistant to bacterial degradation. Metabolism byPseudomonas strain LB400 of PCBs representing a broad spectrum of chlorination patterns and having from two to six chlorines was investigated. Degradation of pure PCB congeners and synthetic congener mixes was measured in resting cell assays with biphenyl- or Luria broth-grown cells. In addition, the appearance of metabolites was followed using HPLC purification, and GC and GC-MS characterization. 2,4,5,2′,4′,5′-[14C]hexachlorobiphenyl was also used to follow the accumulation of14C-labeled metabolites. Evidence indicates that LB400 aerobically metabolizes representatives of all major structural classes of PCB's including several congeners which lack adjacent unchlorinated carbon atoms. The mechanisms by which many of these congeners are degraded are not fully understood, but it is apparent that aerobic bacteria can degrade a broader spectrum of PCB congeners than previously believed and that this broad spectrum of degradative competence can exist in a single strain.

229 citations



Journal ArticleDOI
TL;DR: A microcomputer-based four-quadrant control system of a switched reluctance motor is described, which incorporates a startup operation, sequencing, and synchronized angle steering control.
Abstract: A microcomputer-based four-quadrant control system of a switched reluctance motor is described. The control was implemented with a speed feedback loop, a torque feedback loop, and both the torque and speed feedback loops combined. In addition the controller incorporates a startup operation, sequencing, and synchronized angle steering control. The angle controller was designed using dedicated digital hardware, whereas the other functions were implemented using an Intel 8751 single-chip microcomputer. The complete control system was tested in the laboratory with a 5-hp drive, and the test results were found to be excellent.

Journal ArticleDOI
TL;DR: In this article, a new class of power devices based on an optimal combination of MOS and thyristor elements is described, which can switch from on-to-off or off-toon by applying a voltage to its MOS gate.
Abstract: A new class of power devices is described that is based on an optimal combination of MOS and thyristor elements. Devices of this class function in the ON-state and OFF-state in a manner indistinguishable from a thyristor yet can switch from on-to-off or off-to-on by applying a voltage to its MOS gate. Thus, the devices exhibit extremely low forward drop, high surge current capability, and enjoy negative thermal feedback. To turn off the device, one activates the gate so that FET's are turned on to effectively short one of the emitting junctions of the thyristor. These FET's need only block a maximum of about 1 V when off and carry a sizable current for about 1 µs when on. To turn on the device, any of the normal methods may be employed. However, it is most convenient to use the same MOS gate electrode (and polysilicon layer) and a voltage of the opposite polarity to turn on the thyristor with another FET-just as if it were a normal MOS gated thyristor. The current density that can be turned off depends on the density and effective resistance of the turn-off FET's while turn-on speed and di/ dt rating depend on the initial turn-on area, which in turn depends on the density of the ON-FET's. If the OFF-gate voltage is maintained during the desired OFF-state period, the device has, effectively, an infinite dv/dt capability. Switching speed is most similar to, but somewhat faster than, that of gate turn-off thyristors (GTO's) and, as in other bipolar devices, depends chiefly on carrier recombination time, device thickness, and turn-off di/dt .

Journal ArticleDOI
TL;DR: In this paper, the authors present ab-initio valence-bond calculations on free and coordinated CO 2, and three different coordination geometries for the CO 2 molecule are considered: (a) pure carbon coordination, (b) pure oxygen coordination, and (c) mixed carbon-oxygen coordination.

Patent
15 Dec 1986
TL;DR: In this paper, a transition duct in an advanced heavy duty gas turbine engine is cooled by impingement jets formed by apertures in a sleeve spaced a distance from the surface to be cooled.
Abstract: A transition duct in an advanced heavy duty gas turbine engine is cooled by impingement jets formed by apertures in a sleeve spaced a distance from the surface to be cooled. The sleeve is configured so as to duct spent impingement air towards the combustor, where it can be subsequently used for mixing with, and combustion of, the fuel, or for cooling of the combustor. The distance between the impingement sleeve and the transition duct surface is varied to control the velocity of air crossflow from spent impingement air in order to minimize the pressure loss due to crossflow. The cross-sectional areas of the apertures are varied to project impingement jets over the various distances and crossflow velocities. Generally, larger aperture areas are used with larger distances. The distance between the impingement sleeve and the transition duct systematically increases towards the combustor as the quantity of spent impingement air increases to a maximum value at the intersection of the combustor and the transition duct. The combination of variations in distance, aperture size, and inter-aperture spacing is utilized to vary the impingement cooling intensity to compensate for the variable internal heat load and also to produce the desired temperature distribution over the surface of the transition duct according to design requirements. The aforementioned variations are optimized to minimize the air flow pressure drop ahead of the combustion system which achieving the required cooling intensity according to design requirements.

Patent
25 Feb 1986
TL;DR: An X-ray inspection system for manually or automatically performing digital fluoroscopy inspections and/or computed tomography inspections by Xray examination of manufactured parts incorporates a computer system which automatically analyzes the inspected parts for flaws as discussed by the authors.
Abstract: An X-ray inspection system for manually or automatically performing digital fluoroscopy inspections and/or computed tomography inspections by X-ray examination of manufactured parts incorporates a computer system which automatically analyzes the inspected parts for flaws. The system includes apparatus for automatically positioning the parts in an X-ray machine for obtaining fluoroscopy and tomography views of the part and for acquiring data from the inspections at production rates. The system automatically identifies the location of rejectable flaws in the parts during the fluoroscopy scanning and subsequently identifies those locations for obtaining tomography scans, if the identified flaw location is questionable. The system can automatically reject parts containing flaws identified during the fluoroscopy inspections. This system operates in a real-time environment by providing analysis of one part while a subsequent part is being subjected to X-ray examination. The data obtained during each examination is archived and stored for tracking the part in further manufacturing processes.

Patent
27 May 1986
Abstract: A method and apparatus for measuring stress and strain associated with a pipe, pressurized vessel (12), structural member or deformable body containing a flaw or stress concentration utilizes a laser beam (18) to illuminate a surface (14) being analyzed and an optical data digitizer (20) to sense a signal provided by a speckle pattern produced by the light beam reflected from the illuminated surface. One signal is received from the surface (14) in a reference condition and subsequent signals are received from the surface (14) after surface deformation. The optical data digitizer (20) provides the received signal to an image processor (98), and the processor stores the signals and correlates the deformed image received with the reference image and then sends this correlated information to a minicomputer (28) which performs mathematical analyses of the signal to determine stress and strain associated with the surface. The apparatus is constructed as one integral unit (34), and further includes a digital and tape display (30), as well as a television monitor (26) and an electro-optic range indicator (23).

Journal ArticleDOI
Rida T. Farouki1
TL;DR: A fully automatic tolerance-based surface offset capability may be developed by providing feedback between stages (3) and (2), successive degrees of parametric sub-division being determined by the errors from prior approximations until the desired accuracy is achieved.

Patent
07 Mar 1986
TL;DR: In this article, a geometry process for use in a graphics processing system, especially adapted to couple with a hierarchically structured graphics database memory, a special purpose processor for traversing the database, and a display processor, is presented.
Abstract: A geometry process for use in a graphics processing system, especially adapted to couple with a hierarchically structured graphics database memory, a special purpose processor for traversing the database, and a display processor, wherein the geometry processor includes double-buffered input registers, a first private data bus to the special purpose traversing processor, a second private data bus to the graphics database memory, a high-speed arithmetic processing module, a double-buffered output register, and a microprogrammable control system. The geometry processor is configured to process the graphics database in two passes. The first pass is a culling operation that culls out graphics data supplied from the database memory that is outside of a defined viewing volume, with the culled data being sent over of the first private bus to a stack memory in the traversing processor. The second pass retraverses the culled data, along with additional associated data from the database memory, from the traversing processor's stack memory and transforms that data from a three-dimensional mathematical format to a two-dimensional format suitable for display on a video display system.

Journal ArticleDOI
TL;DR: Several surface analysis tools useful in detecting anomalous surface features including standard techniques such as contouring and high-resolution shaded image displays based on direct ray tracing, and some novel methods such as maps of the principal curvatures, the integration of lines of curvature to show the variation ofthe principal directions.
Abstract: Parametric polynomial surfaces defined to satisfy given interpolatory or boundary constraints often suffer extraneous undesired features because of poor control over their many degrees of freedom. Current techniques for detecting and remedying such unexpected surface characteristics are primitive and inadequate. This article describes several surface analysis tools useful in detecting such anomalous surface features. These include standard techniques such as contouring and high-resolution shaded image displays based on direct ray tracing, and some novel methods such as maps of the principal curvatures, the integration of lines of curvature to show the variation ofthe principal directions, and the determination of geodesic paths on the surface.

Patent
04 Aug 1986
TL;DR: In this article, a method for operating a communication network bridge is described, where the bridge receives a message frame from a first network connected to the source and destination addresses of the received frame and determines if the addresses are contained in a source address table maintained thereby and if both addresses are present, discards the frame.
Abstract: A method for operating a communication network bridge is disclosed. The bridge receives a message frame from a first network connected thereto and reads the source and destination addresses of the received frame. The bridge determines if the addresses are contained in a source address table maintained thereby and if both addresses are present, discards the frame. The bridge transmits the frame to a second network connected thereto if the source address is not in the table or if the source address but not the destination address is in the table.

Book
01 Dec 1986

Journal ArticleDOI
01 Jun 1986
TL;DR: It is proved that a special class of impedances that represent the set of performance specifications are mathematically achievable asymptotically through state-feedback and interaction-force feedforward as actuator bandwidths become large, and a geometrical design method for achieving them in the presence of model uncertainties is offered.
Abstract: A controller design methodology to develop a robust compliant motion for robot manipulators is described. The achievement of the target dynamics (the target impedance is introduced in Part I) and preservation of stability robustness in the presence of bounded model uncertainties are the key issues in the design method. State-feedback and force-feedforward gains are chosen to guarantee the achievement of the target dynamics, while preserving stability in the presence of the model uncertainties. In general, the closed-loop behavior of a system cannot be shaped arbitrarily over an arbitrarily wide frequency range. It is proved that a special class of impedances that represent our set of performance specifications are mathematically achievable asymptotically through state-feedback and interaction-force feedforward as actuator bandwidths become large, and we offer a geometrical design method for achieving them in the presence of model uncertainties. The design method reveals a classical trade-off between a system's performance over a bounded frequency range and its stability relative to model uncertainties via multivariable Nyquits criteria. Two classes of such uncertainties are dealt with. While the first class of model uncertainties is formed from the uncertainties in the parameters of the modeled dynamics, the high-frequency unmodeled dynamics form the second class of model uncertainties. The multivariable Nyquist criterion is used to examine trade-offs in stability robustness against approximation of desired target impedances over bounded frequency ranges.

Journal ArticleDOI
01 Jan 1986-Carbon
TL;DR: In this paper, carbon fibers and carbon/carbon composites have been treated with borate additives and then cured at 500-600°C to produce a continuous film of boron oxide on all exposed surfaces.

Journal ArticleDOI
Deepak Kapur1
TL;DR: The first problem is shown to be equivalent to checking whether a set of polynomial equations does not have a solution; this can be decided by computing a Grobner basis of these polynomials and checking whether I is included in such a basis.

PatentDOI
TL;DR: The system provides smooth, high resolution images which particularly useful for medical diagnostic applications and is particularly useful with conventional display processor hardware used for electronic graphics display.

Patent
22 Sep 1986
TL;DR: In this paper, a control system for an electrically driven variable capacity automotive air conditioning system affords the passenger maximum comfort control without overloading an electric commutated motor compressor drive.
Abstract: A control system for an electrically driven variable capacity automotive air conditioning system affords the passenger maximum comfort control without overloading an electrically commutated motor compressor drive. Driver selected comfort settings are sequentially overridden to avoid overloading the motor. As motor overload conditions are alleviated the control system gradually returns to the initial driver selected comfort settings.

Patent
Theodore Brenig1
13 Nov 1986
TL;DR: In this paper, a weighted average of the measured field strength of the candidate cell and the field strength measured in neighboring cells is calculated for each candidate cell (the field strengths measured by neighboring cells may be multiplied by a weighting factor of 0.5).
Abstract: Wrong handoffs in a cellular radio telephone RF communications system can be minimized or eliminated without increasing locating receiver equipment requirements, field strength measurement time or system response time. Field strength measurements are made at handoff candidate cells and also at cells neighboring (geographically proximate to) those candidate cells. A weighted average of the measured field strength of the candidate cell and the field strength measured in cells neighboring the candidate cell is calculated for each candidate cell (the field strengths measured by neighboring cells may be multiplied by a weighting factor of 0.5). The weighted averages for the candidate cells are compared, and the candidate cell corresponding to the highest average is selected to handle the mobile transceiver call. Statistical analysis shows that this technique for determining handoff candidates significantly reduces the probability that a call will be handed off to a cell which is geographically distant from the mobile transceiver--even in the presence of propagation anomalies.

Patent
10 Sep 1986
TL;DR: In this article, it is shown that collision resolution techniques allow message data scheduling without retransmission of some colliding reservation request packets, and it is also possible to operate in both modes.
Abstract: In a communication system serving a plurality of transmitter-receivers, high capacity is achieved by asynchronous contention access of relatively short reservation request packets, which if successfully transmitted result in the scheduled, noncontention transmission of relatively long message data packets. In a first embodiment, the reservation request packets bear information relating to the duration of the message data packets, so that appropriate message data transmission time may be scheduled. Unsuccessful or colliding reservation request packets are retransmitted. In a second embodiment, the reservation requests packets do not include duration information, and the message data packets have fixed duration. In the second embodiment, collision resolution techniques allow the message data scheduling without retransmission of some colliding reservation request packets. It is also possible to operate in both modes, by scheduling random length message data transmissions as a result of noncolliding reservation request packets, and by scheduling fixed duration message data transmissions when reservation request packets collide.