Computer-aided design of three-port waveguide junction circulators
Lossless three-port H-plane waveguide junction circulator performance evaluation using computerized design
Castillo, J. B., Jr.↗
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Evacuation port seal Patent
Sealing evacuation port and evacuating vacuum container such as space jackets
Woller, J. A.↗
A preliminary study of containment concepts for aircraft landing on elevated STOL-ports
A preliminary study of containment systems for aircraft landing on elevated STOL-ports was conducted as part of an overall study of human acceptance problems associated with STOL operations. The study included a survey and feasibility study of different concepts and a computer analysis of four arrestment systems. The principal conclusion was that a system referred to as the FAA system appears to offer the greatest promise. In this system, standard arresting gear cables are stretched across the roof-top, at roughly 100-foot intervals, but are shielded over the 100-foot-wide primary landing strip. Thus a pilot can land with an arresting hook down, but will not contact the cable unless he swerves off the landing strip, either because he has made a bad landing, or because his landing gear has failed. It was also noted that a suitable curb or guard rail should be developed. Presently available arresting gears and nylon net barriers were considered satisfactory for the overshoot problem.
Haviland, J. K.↗
Air Traffic Forecasting at the Port Authority of New York and New Jersey
Procedures for conducting air traffic forecasts with specific application to the Port Authority of New York and New Jersey are discussed. The procedure relates air travel growth to detailed socio-economic and demographic characteristics of the U.S. population rather than to aggregate economic data such as Gross National Product, personal income, and industrial production. Charts are presented to show the relationship between various selected characteristics and the use of air transportation facilities.
Augustine, J. G.↗
A wind model for an elevated STOL-port configuration
Measurements of mean velocity magnitude and direction as well as three-dimensional turbulence intensity were made in the flow over a model of an elevated STOL-port. A 1:300 scale model was placed in a wind tunnel flow simulating the mean velocity profile and turbulence characteristics of atmospheric winds over a typical city environment excluding detailed wake structures of possible nearby buildings. Hot-wire anemometer measurements of velocity and turbulence were made along approach and departure paths of aircraft operating on the runway centerline and at specified lateral distances from the centerline. Approach flow directions simulated were 0 and 30 degrees to the runway centerline.
Peterka, J. A.↗
MICTPT - A minicomputer general-purpose microwave two-port analysis program
The implementation of a microwave network-analysis program for computers with 4K words of memory is described. The program is capable of the frequency analysis of networks which include interconnections of lumped elements, transmission lines, waveguides, and any two-port which is described by the elements of a scattering matrix. The network can be described mnemonically rather than by numerical codes. For each frequency in the range, the entire network is collapsed into a single equivalent A matrix, and the input impedance and other characteristics are calculated.
Olson, D. H.↗
SEASAT economic assessment. Volume 9: Ports and harbors case study and generalization
This case study and generalization quantify benefits made possible through improved weather forecasting resulting from the integration of SEASAT data into local weather forecasts. The major source of avoidable economic losses to shipping from inadequate weather forecasting data is shown to be dependent on local precipitation forecasting. The ports of Philadelphia and Boston were selected for study.
Source record↗
Design principles of the PORT library
The design of PORT stemmed from the basic principles of portability and ease of use. The attributes and mechanisms used in the library to support this philosophy include the use of a portable subset of FORTRAN, and the use of (machine-dependent) functions to supply the necessary environment parameters. Abbreviated calling sequences are mede possible by a simplified error-handling technique, and by the use of a portable stack allocator for temporary workspace. Experiences to date with these approaches, and plans for the future are reviewed.
Fox, P.↗
Electrical Characterization of Hughes HCMP 1852D and RCA CDP1852D 8-bit, CMOS, I/O Ports
Twenty-five Hughes HCMP 1852D and 25 RCA CDP1852D 8-bit, CMOS, I/O port microcircuits underwent electrical characterization tests. All electrical measurements were performed on a Tektronix S-3260 Test System. Before electrical testing, the devices were subjected to a 168-hour burn-in at 125 C with the inputs biased at 10V. Four of the Hughes parts became inoperable during testing. They exhibited functional failures and out-of-range parametric measurements after a few runs of the test program.
Stokes, R. L.↗
A study of optimum cowl shapes and flow port locations for minimum drag with effective engine cooling, volume 2
The listings, user's instructions, sample inputs, and sample outputs of two computer programs which are especially useful in obtaining an approximate solution of the viscous flow over an arbitrary nonlifting three dimensional body are provided. The first program performs a potential flow solution by a well known panel method and readjusts this initial solution to account for the effects of the boundary layer displacement thickness, a nonuniform but unidirectional onset flow field, and the presence of air intakes and exhausts. The second program is effectually a geometry package which allows the user to change or refine the shape of a body to satisfy particular needs without a significant amount of human intervention. An effort to reduce the cruise drag of light aircraft through an analytical study of the contributions to the drag arising from the engine cowl shape and the foward fuselage area and also that resulting from the cooling air mass flowing through intake and exhaust sites on the nacelle is presented. The programs may be effectively used to determine the appropriate body modifications or flow port locations to reduce the cruise drag as well as to provide sufficient air flow for cooling the engine.
Fox, S. R.↗
An optimization technique for lumped-distributed two ports
A frequency domain direct efficient analysis and an optimization technique of a large class of lumped-distributed networks containing active elements are presented. Sensitivity and Hessian matrix calculations are performed using truncated Taylor series expansion of two-port parameters of subnetworks. An interactive computer program was developed to demonstrate the application of the method. Examples of network optimizations are included to illustrate the powerfulness of the technique.
Iobst, K. W.↗
A general monitor and control interface to the VAX UNIBUS by way of the DR11-C I/O port
The High Speed Data Acquisition System for the Goldstone Solar System Radar requires a number of interfaces for monitor and control functions for the special purpose data acquisition hardware. One common interface design is used. A large number of external control and monitor registers may be addressed and observed with this interface design, by using only three address locations on the UNIBUS and a standard DEC supplied input/output port. A broadcast control and status register is introduced which addresses any number of different units and registers.
Brokl, S. S.↗
A circular combustor configuration with multiple injection ports for mixing enhancement
A circular combustor design by Ghorashi (1988) which resembles a continuously-stirred tank reactor with multiple injection ports is presented with a view to the enhanced control of mixing, NO(x) reduction, and combustion efficiency maximization. Attention is given to the prototype apparatus for this type of circular combustor, which takes the form of a transparent cold-flow reactor for flow visualization studies under 'chemically frozen' conditions.
Ghorashi, B.↗
Ceramic port shields cast in an iron engine head
Silicon nitride exhaust and intake port shields have been successfully cast into a gray iron cylinder head of a heavy duty diesel single cylinder research engine. Careful design considerations, finite element, and probability of survival analyses indicated viability of the design. Foundry experience, NDE, and failure investigations are reported.
Hakim, Nabil S.↗
Hardening communication ports for survival in electrical overstress environments
Greater attention is being focused on the protection of data I/O ports since both experience and lab tests have shown that components at these locations are extremely vulnerable to electrical overstress (EOS) in the form of transient voltages. Lightning and electrostatic discharge (ESD) are the major contributors to these failures; however, these losses can be prevented. Hardening against transient voltages at both the board level and system level has a proven record of improving reliability by orders of magnitude. The EOS threats, typical failure modes, and transient voltage mitigation techniques are reviewed. Case histories are also reviewed.
Clark, O. Melville↗
Low loss waveguide four-port crossover circuit and its application for cross-slot antenna feed
A four-way crossover circuit using a cylindrical cavity with four rectangular input/output ports has been designed to feed a cross-slot antenna to achieve dual polarization. Because all the input and output circuits are waveguides, the network is especially useful for high power systems and millimeter wave applications. The crossover circuit exhibits a very low insertion loss and good isolation.
Chang, K.↗
Calibration Valve With Built-In Test Port
Calibration valve includes built-in test port for calibrating control-panel gauges in place, without having to remove them for calibration. Use of this valve reduces number of plumbing parts and thus number of potential leakage points. Application of calibration valve saves time when calibrating control-panel gauges or transducers and prevents damage or loss of instruments by not having to remove them from control panel for calibration.
Pilichi, Carmine A.↗
An Experimental Determination of Losses in a 3-Port Wave Rotor
Wave rotors, used in a gas turbine topping cycle, offer a potential route to higher specific power and lower specific fuel consumption. In order to exploit this potential properly, it is necessary to have some realistic means of calculating wave rotor performance, taking losses into account, so that wave rotors can be designed for good performance. This in turn requires a knowledge of the loss mechanisms. The experiment reported here was designed as a statistical experiment to identify the losses due to finite passage opening time, friction, and leakage. For simplicity, the experiment used a 3-port, flow divider, wave cycle, but the results should be applicable to other cycles. A 12 inch diameter rotor was used, with two different lengths, 9 inches and 18 inches, and two different passage widths, 0.25 inch and 0.54 inch, in order to vary friction and opening time. To vary leakage, moveable end-walls were provided so that the rotor to end-wall gap could be adjusted. The experiment is described, and the results are presented, together with a parametric fit to the data. The fit shows that there will be an optimum passage width for a given wave rotor, since, as the passage width increases, friction losses decrease, but opening-time losses increase, and vice-versa. Leakage losses can be made small at reasonable gap sizes.
Wilson, Jack↗