Design, Requirements, and Performance of Space Vehicles with Simple Solar Photon Thrusters

2021 ◽  
pp. 1-14
Author(s):  
Guillermo A. Corrado ◽  
Walkiria Schulz
Keyword(s):  
Space Vehicles ◽  
Design Requirements ◽  
And Performance

Nondestructive Test on Typical Roadway Supports of a Mine via Drilling Core and Ground Penetrating Radar

2011 ◽  
Vol 368-373 ◽  
pp. 2411-2416
Author(s):  
Jian Ping Han ◽  
Hai Peng Liu
Keyword(s):  
Ground Penetrating Radar ◽  
Geological Structure ◽  
Surrounding Rock ◽  
Potential Threat ◽  
Real Performance ◽  
Design Requirements ◽  
And Performance ◽  
The Stability ◽  
Ground Penetrating ◽  
Drilling Core

Temporary or permanent supports are necessary in underground construction for maintaining the stability and limiting the damage of surrounding rock. Due to the uncertainty of geological structure, the specificity of the underground environment as well as other factors, the quality and performance of supporting structure are often difficult to satisfy the design requirements, which not only seriously affects the normal construction and operation of mines but also has the potential threat to the safety of underground production. In order to investigate the influence of the unfavorable geologic environment on supporting concrete and evaluate the real performance of roadway supports of a mine, 17 typical projects were chosen and the strength of supporting concrete was detected by nondestructive drilling core method. The result shows that the strength is widely less than the design value. Furthermore, 4 projects of them were investigated by the ground penetrating radar (GPR) in order to evaluate the feasibility of GPR in the performance investigation of the roadway supports of a mine. The results indicate that ground penetrating radar is capable of measuring the thickness of the support, the distribution of rebars and the defects of the surrounding rock.

HTHL Space Vehicles: Concepts and Control Problems

2014 ◽  
Vol 629 ◽  
pp. 382-387
Author(s):  
Alexander Nebylov
Keyword(s):  
Control Systems ◽  
Ground Effect ◽  
Easy Access ◽  
Space Vehicles ◽  
Space Launch ◽  
Design Requirements ◽  
Last Stage ◽  
Launch Systems ◽  
And Control ◽  
Aerospace Plane

Integrated launch systems that include aerospace plane (ASP) and another heavy winged vehicle (plane or better Wing-in-Ground effect vehicle) as a booster are reviewed. It is shown that WIG-vehicle with a mass of 1500 ton or more is capable to carry ASP with initial mass of 500 ton and landing mass of 60-70 ton. Ekranoplane can provide ASP with the primary speed of Mach 0.5-0.65 in the required direction that allows lowering the design requirements to ASP's wing area and engines. A number of other advantages from the offered transport system are linked to possible use of WIG-vehicle at ASP landing. Heavy WIG-vehicle is unique vehicle for realizing the progressive idea of docking to descending ASP, allowing expanding opportunities of its landing. The problem of ASP horizontal landing without undercarriage by docking with other flying vehicle at the last stage of decent and the requirements to control systems for relative motion control of both vehicles are discussed. The progressive idea of joining space launch technologies with marine technologies is developed. It is especially important for countries with strongly limited areas of land territory but with easy access to the ocean.

H∞ loop Shaping Robust Postprandial Glucose Control for Type 1 Diabetes

2021 ◽  
Vol 39 (2A) ◽  
pp. 268-279
Author(s):  
Safa F. Fadhel ◽  
Safanah M. Raafat
Keyword(s):  
Blood Glucose Concentration ◽  
Artificial Pancreas ◽  
Postprandial Glucose ◽  
Robust Controller ◽  
Control Effort ◽  
Loop Shaping ◽  
Design Requirements ◽  
And Performance

The Bergman model is one of the most commonly used models applied to the representation of the artificial pancreas (AP). It is important to study the effects of the insulin infusion on blood glucose concentration. This work includes a case study for the design of a robust controller for an AP. Robustness is a structured control that improves a system's ability to keep its stability and performance under various conditions. The proposed H∞ loop shaping HLS method will fulfill the design requirements of robust control and performance. The results of the simulation prove the superiority of the intended approach in terms of simple structure, robust performance, and stability with the least control effort

Viterbi Decoder in Hardware

2018 ◽  
pp. 6307-6318
Author(s):  
Mário Pereira Véstias
Keyword(s):  
Maximum Likelihood ◽  
Viterbi Algorithm ◽  
Viterbi Decoder ◽  
Maximum Likelihood Decoding ◽  
High Data ◽  
Design Requirements ◽  
Trellis Decoding ◽  
And Performance ◽  
Viterbi Decoders ◽  
Very High

Trellis decoding is used to recover encoded information that was corrupted during transmission over a noisy channel. The Viterbi algorithm is the most well known trellis-based maximum likelihood decoding algorithm. The Viterbi algorithm is executed by a Viterbi decoder. Different hardware solutions may be considered to implement a Viterbi decoder with different design requirements in terms of area, performance, power consumption, among others. The most appropriate solution depends on the metric requirements of the application as well as on the target technology. Properties of the Viterbi algorithm are used to simplify and improve the architecture of the Viterbi decoder. In particular, statistical properties of the Viterbi algorithm are used to design parallel Viterbi decoders with very high data decoding rates. The article focuses on the implementation of a Viterbi decoder in hardware, including optimizations to improve the area and performance.

Design of Separating Screen for Tenebrio molitor L

2014 ◽  
Vol 543-547 ◽  
pp. 258-262
Author(s):  
Li Ping Wang ◽  
Yi Guo ◽  
Gang Fu ◽  
Jiang Hui Dong
Keyword(s):  
Performance Test ◽  
High Efficiency ◽  
Structural Parameters ◽  
Low Cost ◽  
Tenebrio Molitor ◽  
Vector Method ◽  
Working Principle ◽  
Design Requirements ◽  
And Performance ◽  
Easy Operation

In order to meet requirement of separation screen for tenebrio molitor L, one separation screen was designed, this product has a good separation, simple structure, low cost, high efficiency, easy operation. Based on the analysis of design requirement of separating screen for tenebrio molitor L, overall structure, working principle and the main structural parameters were determined. The kinematic mathematical model of shaking mechanism was established by using the vector method. The kinematics analysis of shaking mechanism was conducted by using Matlab, the displacement, velocity and acceleration curves of sieve box were obtained. The performance test showed that the prototype machine can screen different instar tenebrio molitor L and frass, this machine has good screening effect. In addition, machine design and performance are able to meet the design requirements.

scholarly journals AERODYNAMIC THRUST CHARACTERISTICS AND PERFORMANCE VALUATIONS FOR AN AEROSPIKE NOZZLE- REVIEW

2021 ◽  
Vol 5 (11) ◽  
Author(s):  
Ankit Kumar Mishra ◽  
Vinit Goswami ◽  
Priyanka Sarma
Keyword(s):  
Performance Analysis ◽  
Research And Development ◽  
Review Paper ◽  
Single Stage ◽  
Development Work ◽  
Space Vehicles ◽  
Thrust Characteristics ◽  
And Performance ◽  
Aerospike Nozzle ◽  
Emerging Topics

Aerospike nozzles are now-a-days one of the most emerging topics for research and development work leading for the futuristic goals of an aerospace industries and organizations. They are indulging in a class of elevation balancing nozzle engines. These nozzle engines are basically constructed for single-stage-to-orbit (SSTO) as well as foremost engine for space vehicles. These nozzles are about 75% shorter than the standard nozzle for similar expansion ratios. Aerodynamic thrust variation and performances play a key role in estimating forces along with the injected flow and their characteristics. This review paper deals with the aerodynamics characterization, its properties at different conditions in addition with the performance analysis of the aerospike nozzle.

Performance Evaluation of an MR-Compatible Rotating Anode X-Ray Tube

2013 ◽  
Author(s):  
Mihye Shin ◽  
Prasheel Lillaney ◽  
Waldo Hinshaw ◽  
Rebecca Fahrig
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Magnetic Moments ◽  
X Ray ◽  
Close Proximity ◽  
Motor Design ◽  
Design Requirements ◽  
And Performance ◽  
The Magnetic Field ◽  
Lorentz Force Law

The key technical innovation needed for close proximity hybrid x-ray/MR (XMR) imaging systems is a new rotating anode x-ray tube motor that can operate in the presence of strong magnetic fields. In order for the new motor design to be optimized between conflicting design requirements, we implemented a numerical model for evaluating the dynamics of the motor. The model predicts the amount of produced torque, rotation speed, and time to accelerate based on the Lorentz force law; the motor is accelerated by the interaction between the magnetic moments of the motor wire loops and an external magnetic field. It also includes an empirical model of bearing friction and electromagnetic force from the magnetic field. Our proposed computational model is validated by experiments using several different magnitudes of external magnetic fields, which averagely shows an agreement within 0.5 % error during acceleration. We are using this model to improve the efficiency and performance of future iterations of the x-ray tube motor.

Viterbi Decoder in Hardware

2019 ◽  
pp. 1138-1152
Author(s):  
Mário Pereira Véstias
Keyword(s):  
Maximum Likelihood ◽  
Viterbi Algorithm ◽  
Viterbi Decoder ◽  
Maximum Likelihood Decoding ◽  
High Data ◽  
Design Requirements ◽  
Trellis Decoding ◽  
And Performance ◽  
Viterbi Decoders ◽  
Very High

Trellis decoding is used to recover encoded information that was corrupted during transmission over a noisy channel. The Viterbi algorithm is the most well-known trellis-based maximum likelihood decoding algorithm. The Viterbi algorithm is executed by a Viterbi decoder. Different hardware solutions may be considered to implement a Viterbi decoder with different design requirements in terms of area, performance, power consumption, among others. The most appropriate solution depends on the metric requirements of the application as well as on the target technology. Properties of the Viterbi algorithm are used to simplify and improve the architecture of the Viterbi decoder. In particular, statistical properties of the Viterbi algorithm are used to design parallel Viterbi decoders with very high data decoding rates. The chapter focuses on the implementation of a Viterbi decoder in hardware, including optimizations to improve the area and performance.

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