RCS Depressurization and Loss of Flow No Trip 3D Neutronic Transient Analyses

2008 ◽  
Author(s):  
Cenk Gu¨ler ◽  
Daniel H. Risher
Keyword(s):  
Nucleate Boiling ◽  
System A ◽  
Digital Instrumentation ◽  
Complete Failure ◽  
Core Height ◽  
Operator Action ◽  
Analog Systems ◽  
Digital Protection ◽  
And Control ◽  
Point Kinetics

To be able to correctly analyze an RCS Depressurization or Loss of Flow accident with no reactor trip, the Westinghouse 3D Transient Neutronics tool RAVE™ was used. Plants which utilize all-digital Instrumentation and Control (I&C) systems may be required to consider a complete failure of the digital protection system. A backup analog system is provided in the event of a failure of the digital system; however the backup analog systems do not carry all safety trip signals. Therefore, it is postulated that the plant might experience an accident event in which no immediate trip signal is generated and protection would rely on operator action. To allow adequate time for the operator to recognize the malfunction and take action to manually trip the plant, it is assumed that operator action will not occur for ten minutes from the initiation of the transient. These kinds of transients may be analyzed with point kinetic transient codes; however, due to the lack of 3D neutronic feedback with a core height dependent moderator temperature coefficient and its effect on the axial and radial power distributions, it may not be possible to show that Departure from Nucleate Boiling (DNB) does not occur. Using 3D Neutronic transient analyses methods (RAVE™), it was shown that neither of these transients (RCS Depressurization or Loss of Flow) would generate DNB violations, even though the point kinetics version is showing the opposite.

Modeling human-like longitudinal driver model for intelligent vehicles based on reinforcement learning

2021 ◽  
pp. 095440702098357
Author(s):  
Ju Xie ◽  
Xing Xu ◽  
Feng Wang ◽  
Haobin Jiang
Keyword(s):  
Reinforcement Learning ◽  
Comprehensive Evaluation ◽  
Path Following ◽  
Intelligent Vehicles ◽  
Driver Model ◽  
Control Center ◽  
Training Performance ◽  
Learning Agents ◽  
System A ◽  
And Control

The driver model is the decision-making and control center of intelligent vehicle. In order to improve the adaptability of intelligent vehicles under complex driving conditions, and simulate the manipulation characteristics of the skilled driver under the driver-vehicle-road closed-loop system, a kind of human-like longitudinal driver model for intelligent vehicles based on reinforcement learning is proposed. This paper builds the lateral driver model for intelligent vehicles based on optimal preview control theory. Then, the control correction link of longitudinal driver model is established to calculate the throttle opening or brake pedal travel for the desired longitudinal acceleration. Moreover, the reinforcement learning agents for longitudinal driver model is parallel trained by comprehensive evaluation index and skilled driver data. Lastly, training performance and scenarios verification between the simulation experiment and the real car test are performed to verify the effectiveness of the reinforcement learning based longitudinal driver model. The results show that the proposed human-like longitudinal driver model based on reinforcement learning can help intelligent vehicles effectively imitate the speed control behavior of the skilled driver in various path-following scenarios.

Complete Failure Analysis of Attitude Determination and Control System

2021 ◽  
Author(s):  
Disha Gundecha ◽  
Nishant Gavhane ◽  
Vedant Dubey ◽  
Sahil Joshi ◽  
Pranav Karve ◽  
...  
Keyword(s):  
Control System ◽  
Failure Analysis ◽  
Attitude Determination ◽  
Complete Failure ◽  
And Control

Design and Simulation of Pedal Simulator in Brake by Wire System

2014 ◽  
Vol 556-562 ◽  
pp. 1358-1361 ◽  
Author(s):  
Wen Bo Zhu ◽  
Fen Zhu Ji ◽  
Xiao Xu Zhou
Keyword(s):  
Simulation Models ◽  
Control Algorithms ◽  
Brake Pedal ◽  
Braking System ◽  
Pedal Force ◽  
Performance Requirements ◽  
System A ◽  
Pedal Feel ◽  
And Control ◽  
Wire System

Wire of the brake pedal is not directly connected to the hydraulic environment in the braking By-wire system so the driver has no direct pedal feel. Then pedal simulator is an important part in the brake-by-wire system. A pedal force simulator was designed based on the traditional brake pedal curve of pedal force and pedal travel, AMESim and Matlab / Simulink were used as a platform to build simulation models and control algorithms. The simulation results show that the pedal stroke simulator and the control strategy meet the performance requirements of traditional braking system. It can be used in brake by wire system.

scholarly journals VILNIUS ADVANCED-SURFACE MOVEMENT GUIDANCE AND CONTROL SYSTEM (A-SMGCS) SAFETY OBJECTIVES / VILNIAUS AERODROMO AUTOMATIZUOTOS ANTŽEMINIO EISMO STEBĖJIMO IR KONTROLĖS SISTEMOS SAUGOS TIKSLŲ ANALIZĖ

Aviation ◽  
2012 ◽  
Vol 16 (4) ◽  
pp. 130-135
Author(s):  
Vaidotas Kondroška ◽  
Jonas Stankūnas
Keyword(s):  
Control System ◽  
System Analysis ◽  
Flight Safety ◽  
Frequency Of Occurrence ◽  
Surface Movement ◽  
Safety Requirements ◽  
Methods Of Determination ◽  
Guidance And Control ◽  
System A ◽  
And Control

This work reviews the innovative and progressive methods of determination and analysis of safety objectives using Vilnius A-SMGCS example. The aim of the analysis is to determine how failures in this system could affect flight safety in Vilnius aerodrome. Identified safety objectives will limit the frequency of occurrence of hazards enough for the associated risk to be acceptable, and will ensure that appropriate mitigation means are reflected subsequently as Safety Requirements for the system. Analysis reflects aspects of A-SMGCS Safety objectives, which should be taken into consideration. Santrauka Darbe apžvelgiami progresyvūs saugos tikslų analizės metodai pagal Vilniaus aerodromo automatizuotos antžeminio eismo stebėjimo ir kontrolės sistemos veiklos pavyzdį. Analizuojama, kaip šios sistemos sutrikimai gali paveikti skrydžių saugą Vilniaus aerodrome. Remiantis galimų pavojų skrydžių saugai analize, tyrime nustatyti saugos tikslai, pagal kuriuos vėliau bus numatomos riziką mažinančios priemonės (galimų pavojų neutralizavimui ar kylančios rizikos sumažinimui iki priimtino lygio). Straipsnyje pateikiami veiksniai, kuriuos reikėtų įvertinti nustatant aerodromo automatizuotos antžeminio eismo stebėjimo ir kontrolės sistemos saugos tikslus.

Development of a Substation Digital Protection and Control System Using a Fiber-Optic Local Area Network

1989 ◽  
Vol 9 (7) ◽  
pp. 51-52 ◽  
Author(s):  
M. Suzuki ◽  
T. Matsuda ◽  
N. Ohashi ◽  
Y. Sano ◽  
R. Tsukui ◽  
...  
Keyword(s):  
Control System ◽  
Fiber Optic ◽  
Local Area Network ◽  
Local Area ◽  
Area Network ◽  
Digital Protection ◽  
Protection And Control ◽  
And Control

Cost-Effectiveness of Paving Fabrics Used to Control Reflective Cracking

2000 ◽  
Vol 1730 (1) ◽  
pp. 139-149 ◽  
Author(s):  
William G. Buttlar ◽  
Diyar Bozkurt ◽  
Barry J. Dempsey
Keyword(s):  
Life Cycle ◽  
Cost Effectiveness ◽  
Department Of Transportation ◽  
Reflective Cracking ◽  
Crack Control ◽  
Condition Rating ◽  
System A ◽  
Rigid Pavements ◽  
The Cost ◽  
And Control

The Illinois Department of Transportation (IDOT) spends $2 million annually on reflective crack control treatments; however, the cost-effectiveness of these treatments had not been reliably determined. A recent study evaluated the cost-effectiveness of IDOT reflective crack control System A, which consists of a nonwoven polypropylene paving fabric, placed either in strips longitudinally over lane-widening joints or over the entire pavement (area treatment). The study was limited to projects constructed originally as rigid pavements and subsequently rehabilitated with one or more bituminous overlays. Performance of 52 projects across Illinois was assessed through crack mapping and from distress and serviceability data in IDOT’s condition rating survey database. Comparisons of measured reflective cracking in treated and control sections revealed that System A retarded longitudinal reflective widening crack development, but it did not significantly retard transverse reflective cracking, which agrees with earlier studies. However, both strip and area applications of these fabric treatments appeared to improve overall pavement serviceability, and they were estimated to increase rehabilitation life spans by 1.1 and 3.6 years, respectively. Reduction in life-cycle costs was estimated to be 4.4 and 6.2 percent when placed in medium and large quantities, respectively, and to be at a break-even level for small quantities. However, life-cycle benefits were found to be statistically insignificant. Limited permeability testing of field cores taken on severely distressed transverse joints suggested that waterproofing benefits could exist even after crack reflection. This was consistent with the observation that, although serviceability was generally improved with area treatment, crack reflection was not retarded relative to untreated areas.

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