Real time digital propulsion system simulation for manned flight simulators

A real time digital simulation of a STOL propulsion system was developed which generates significant dynamics and internal variables needed to evaluate system performance and aircraft interactions using manned flight simulators. The simulation ran at a real-to-execution time ratio of 8.8. The model was used in a piloted NASA flight simulator program to evaluate the simulation technique and the propulsion system digital control. The simulation is described and results shown. Limited results of the flight simulation program are also presented

A Link Quality Model for Generalised Frequency Division Multiplexing

5G systems aim to achieve extremely high data rates, low end-to-end latency and ultra-low power consumption. Recently, there has been considerable interest in the design of 5G physical layer waveforms. One important candidate is Generalised Frequency Division Multiplexing (GFDM). In order to evaluate its performance and features, system-level studies should be undertaken in a range of scenarios. These studies, however, require highly complex computations if they are performed using bit-level simulators. In this paper, the Mutual Information (MI) based link quality model (PHY abstraction), which has been regularly used to implement system-level studies for Orthogonal Frequency Division Multiplexing (OFDM), is applied to GFDM. The performance of the GFDM waveform using this model and the bit-level simulation performance is measured using different channel types. Moreover, a system-level study for a GFDM based LTE-A system in a realistic scenario, using both a bit-level simulator and this abstraction model, has been studied and compared. The results reveal the accuracy of this model using realistic channel data. Based on these results, the PHY abstraction technique can be applied to evaluate the performance of GFDM based systems in an effective manner with low complexity. The maximum difference in the Packet Error Rate (PER) and throughput results in the abstraction case compared to bit-level simulation does not exceed 4% whilst offering a simulation time saving reduction of around 62,000 times.Comment: 5 pages, 8 figures, accepted in VTC- spring 201

G-189A analytical simulation of the integrated waste management-water system using radioisotopes for thermal energy

An analytical simulation of the RITE-Integrated Waste Management and Water Recovery System using radioisotopes for thermal energy was prepared for the NASA-Manned Space Flight Center (MSFC). The RITE system is the most advanced concept water-waste management system currently under development and has undergone extended duration testing. It has the capability of disposing of nearly all spacecraft wastes including feces and trash and of recovering water from usual waste water sources: urine, condensate, wash water, etc. All of the process heat normally used in the system is produced from low penalty radioisotope heat sources. The analytical simulation was developed with the G189A computer program. The objective of the simulation was to obtain an analytical simulation which can be used to (1) evaluate the current RITE system steady state and transient performance during normal operating conditions, and also during off normal operating conditions including failure modes; and (2) evaluate the effects of variations in component design parameters and vehicle interface parameters on system performance

Using Simulation To Evaluate The Performance Of Internet Payment System : A Case On Cybank

The Internet Payment System (IPS) is the latest means of doing financial transactions over the Internet. Howvever. its inefficient usage anlong Internet users has become a prime discussion anlong many folks and many tentative assumptions were made. Hence, the first aspect of this research was aimed to identify problems and reasons that caused this hindrance. The result indicated the time-consuming factor to process real-time requests as one of its main deficiency. A few performance enhancement approaches were recognized and Cybank's management was stimulated to counter those predicaments in order to excite its current and potential users in employing Cybank. This is in line with Cybank's vision, which is to be a world class IPS supplier in the IPS industry. The second aspect of this research covered the use of simulation in modeling the operational behavior of Cybank. It has been proven that this technique is very effective in modeling such complex systems like the IPS. The simulation technique has also succeeded in recommending appropriate and sound changes that could be implemented on Cybank, based on the quantitative result acquired from experiments performed on the built model

Development and modification of a digital program for final approach to landing

The development and implementation of a dynamic digital computer simulator which may be used to evaluate aircraft performance when operating under the control and guidance of various navigation, landing, and flight control systems are discussed. The digital computer program may be used to simulate and evaluate the relationships and interactions between various factors such as the microwave landing system, avionics receivers and onboard processors, aircraft aerodynamics, aircraft automatic control systems, control surfaces, and wind and other external effects. The models used to represent aircraft aerodynamics, control system and control surfaces; weather and wind effects; and the microwave landing system are described. Example results are presented for a simulation of a Boeing 737 using two sample control systems while subjected to various atmospheric conditions and microwave landing system errors. The limitations and performance capabilities of these control systems are discussed in terms of their ability to utilize the microwave landing system signal

Performance Evaluation of Low Density Spreading Multiple Access

In this paper, we evaluate the performance of Multicarrier-Low Density Spreading Multiple Access (MC-LDSMA) as a multiple access technique for mobile communication systems. The MC-LDSMA technique is compared with current multiple access techniques, OFDMA and SC-FDMA. The performance is evaluated in terms of cubic metric, block error rate, spectral efficiency and fairness. The aim is to investigate the expected gains of using MC-LDSMA in the uplink for next generation cellular systems. The simulation results of the link and system-level performance evaluation show that MC-LDSMA has significant performance improvements over SC-FDMA and OFDMA. It is shown that using MC-LDSMA can considerably reduce the required transmission power and increase the spectral efficiency and fairness among the users

Physics Prospects at the HL-LHC with ATLAS

The High-Luminosity LHC aims to provide a total integrated luminosity of 3000 fb−1 from proton-proton collisions at √ s = 14 TeV over the course of ∼ 10 years, reaching instantaneous luminosities of up to L = 7.5 × 1034cm−2 s −1 , corresponding to an average of 200 inelastic pp collisions per bunch crossing (µ = 200) . The upgraded ATLAS detector and trigger system must be able to cope well with increased occupancies and data rates. The performance of the upgrade has been estimated in full simulation studies, assuming expected HL-LHC conditions and a detector configuration intended to maximise physics performance and discovery potential at the HL-LHC, and is expected to be similar to current performance. Fast simulation studies have been carried out to evaluate the prospects of various benchmark physics analyses to be performed using the upgraded ATLAS detector with the full HL-LHC dataset