Conformal elastohydrodynamic lubrication analysis for engine bearing design: A brief review

2010 ◽  
Vol 224 (12) ◽  
pp. 2648-2653 ◽  
Author(s):  
J F Booker ◽  
S Boedo ◽  
D Bonneau
Keyword(s):  
Elastohydrodynamic Lubrication ◽  
Physical Models ◽  
Large Sample ◽  
Current State ◽  
Solution Methods ◽  
Bearing Design ◽  
Engine Bearing

The history and current state of conformal elastohydrodynamic lubrication analysis for engine bearing design is reviewed through a large sample of its published literature. Major themes of the physical models and solution methods are examined, together with attention to important special categories of current research.

French and Spanish Queer Film

2016 ◽  
Author(s):  
Chris Perriam ◽  
Darren Waldron
Keyword(s):  
Focus Groups ◽  
Sense Of Community ◽  
National Identities ◽  
Audience Research ◽  
Large Sample ◽  
Current State ◽  
Trans People ◽  
Screening Questionnaires ◽  
On Line ◽  
The Uk

This book advances the current state of film audience research and of our knowledge of sexuality in transnational contexts, by analysing how French LGBTQ films are seen in Spain and Spanish ones in France, as well as how these films are seen in the UK. It studies films from various genres and examines their reception across four languages (Spanish, French, Catalan, English) and engages with participants across a range of digital and physical audience locations. A focus on LGBTQ festivals and on issues relating to LGBTQ experience in both countries allows for the consideration of issues such as ageing, sense of community and isolation, affiliation and investment, and the representation of issues affecting trans people. The book examines films that chronicle the local, national and sub-national identities while also addressing foreign audiences. It draws on a large sample of individual responses through post-screening questionnaires and focus groups as well as on the work of professional film critics and on-line commentators.

Public Facilities Design in Sustainable Ways for Reconstruction Work of Yushu Area

2014 ◽  
Vol 672-674 ◽  
pp. 2195-2210
Author(s):  
Ang Li ◽  
Shu Bin Kan ◽  
Xin Zhang ◽  
Xin Yu Song ◽  
Shi Long Zhang
Keyword(s):  
Design Theory ◽  
Physical Models ◽  
Overall Design ◽  
Public Facilities ◽  
Local Characteristics ◽  
Current State ◽  
Environmental Friendly ◽  
The World ◽  
Facilities Design ◽  
Pros And Cons

The region of Yushu has fragile natural environment. In 2010, it suffered severe damages caused by earthquakes. This paper subject, on the basis of status research of natural and cultural environment in Yushu area and urban public facilities across the world, is aiming at a design attempt of public facilities suitable for Yushu area under the guidance of sustainable-development design theory. After constructing computer models, we made physical models to further test the reliability of our scheme. The overall design acts according to circumstances, and makes it environmental friendly, developmental sustainable, economical, aesthetic, practical and reliable. We also added to our design some local characteristics to make it better integrate into the local natural environmental features so that it could be widely used. In the end, we summarized the pros and cons of the scheme through theoretical analysis of our design process, despite that, in June 2014, we had an on-the-spot investigation in Yushu, and according to its current state of development, we made outlooks of our further scheme practice.

scholarly journals Decision-Theoretic Planning with non-Markovian Rewards

2006 ◽  
Vol 25 ◽  
pp. 17-74 ◽  
Author(s):  
S. Thiebaux ◽  
C. Gretton ◽  
J. Slaney ◽  
D. Price ◽  
F. Kabanza
Keyword(s):  
Decision Process ◽  
Single Interface ◽  
Reward Function ◽  
Domain Specific ◽  
Current State ◽  
Markovian Decision Process ◽  
Solution Methods ◽  
Control Knowledge ◽  
Search Control ◽  
Domain Independent

A decision process in which rewards depend on history rather than merely on the current state is called a decision process with non-Markovian rewards (NMRDP). In decision-theoretic planning, where many desirable behaviours are more naturally expressed as properties of execution sequences rather than as properties of states, NMRDPs form a more natural model than the commonly adopted fully Markovian decision process (MDP) model. While the more tractable solution methods developed for MDPs do not directly apply in the presence of non-Markovian rewards, a number of solution methods for NMRDPs have been proposed in the literature. These all exploit a compact specification of the non-Markovian reward function in temporal logic, to automatically translate the NMRDP into an equivalent MDP which is solved using efficient MDP solution methods. This paper presents NMRDPP (Non-Markovian Reward Decision Process Planner), a software platform for the development and experimentation of methods for decision-theoretic planning with non-Markovian rewards. The current version of NMRDPP implements, under a single interface, a family of methods based on existing as well as new approaches which we describe in detail. These include dynamic programming, heuristic search, and structured methods. Using NMRDPP, we compare the methods and identify certain problem features that affect their performance. NMRDPP's treatment of non-Markovian rewards is inspired by the treatment of domain-specific search control knowledge in the TLPlan planner, which it incorporates as a special case. In the First International Probabilistic Planning Competition, NMRDPP was able to compete and perform well in both the domain-independent and hand-coded tracks, using search control knowledge in the latter.

Mantras of wildland fire behaviour modelling: facts or fallacies?

2017 ◽  
Vol 26 (11) ◽  
pp. 973 ◽  
Author(s):  
Miguel G. Cruz ◽  
Martin E. Alexander ◽  
Andrew L. Sullivan
Keyword(s):  
Wildland Fire ◽  
Original Data ◽  
Fire Spread ◽  
Empirical Models ◽  
Physical Models ◽  
Fire Behaviour ◽  
Fire Science ◽  
Current State ◽  
Valid Data ◽  
Insight Into

Generalised statements about the state of fire science are often used to provide a simplified context for new work. This paper explores the validity of five frequently repeated statements regarding empirical and physical models for predicting wildland fire behaviour. For empirical models, these include statements that they: (1) work well over the range of their original data; and (2) are not appropriate for and should not be applied to conditions outside the range of the original data. For physical models, common statements include that they: (3) provide insight into the mechanisms that drive wildland fire spread and other aspects of fire behaviour; (4) give a better understanding of how fuel treatments modify fire behaviour; and (5) can be used to derive simplified models to predict fire behaviour operationally. The first statement was judged to be true only under certain conditions, whereas the second was shown not to be necessarily correct if valid data and appropriate modelling forms are used. Statements three through five, although theoretically valid, were considered not to be true given the current state of knowledge regarding fundamental wildland fire processes.

Engine Bearing Design

2015 ◽  
pp. 193-214
Author(s):  
Kevin Hoag ◽  
Brian Dondlinger
Keyword(s):  
Bearing Design ◽  
Engine Bearing

Conrod Bearings With an Optimized Narrow Circumferential Oil Groove: Simulated Durability Improvement for Heavy-Duty Applications

2015 ◽  
Vol 137 (10) ◽  
Author(s):  
Konstantinos Kalogiannis ◽  
David R. Merritt ◽  
Omar Mian ◽  
Hugh Gibson
Keyword(s):  
Negative Impact ◽  
Elastohydrodynamic Lubrication ◽  
Design Feature ◽  
Operating Conditions ◽  
Temperature Dependent ◽  
Operating Life ◽  
Oil Film ◽  
Significant Temperature ◽  
Bearing Design ◽  
Engine Crankshaft

Under normal operating conditions, engine crankshaft bearings experience variations in oil film temperature due to shearing of the oil film. This can have a negative impact on the bearing operating life since the viscosity of the lubricant is temperature dependent. In the current study, a thermo-elastohydrodynamic lubrication (TEHL) analysis has been conducted using an in-house specialized simulation package called (software for analysis of bearings in reciprocating engines) SABRE-TEHL. This advanced simulation tool has been used to optimize a new bearing design feature leading to a significant temperature reduction, which in turn increases the robustness of the system.

Refinement of Engine Bearing Design Techniques

1993 ◽  
Author(s):  
J. M. Conway-Jones ◽  
Neil Tarver
Keyword(s):  
Bearing Design ◽  
Engine Bearing ◽  
Design Techniques

scholarly journals The expert system for assessing fire risks of electrical installations in the agrarian industrial complex based on neural networks

2021 ◽  
Vol 2142 (1) ◽  
pp. 012005
Author(s):  
M A Gabova ◽  
O K Nikolsky ◽  
M V Guner
Keyword(s):  
Risk Assessment ◽  
Environmental Parameters ◽  
Fire Risk ◽  
Material Damage ◽  
Industrial Complex ◽  
Current State ◽  
Risk Of Injury ◽  
Solution Methods ◽  
The Given ◽  
Electrical Installation

Abstract The article is devoted to the analysis of fire risks of the operation of electrical installations in the agro-industrial complex of the region. According to statistics, the number of fires occurring for electrical reasons is steadily increasing, which makes the issue of fire risk management relevant. In order to identify and prevent these risks, a technogenic safety system has been developed, presented as a set of methods and tools, which are based on the generation of new data on the causes of threats to the operation of electrical installations based on the analysis of data on the current state of the system. Highlighted characteristics such as Human Parameters, Electrical Installation Parameters and Environmental Parameters. Mathematical models of the given components are considered, a fire risk assessment tree is compiled, in which the input parameters and intermediate vertices with the solution methods in them were determined. The developed model can be used to carry out experiments in order to study the behavior of an electrical installation under various conditions. The application of this method is especially important in cases where the removal of indicators and testing of the operation of an electrical installation is impossible due to the risk of injury or material damage.

scholarly journals Use of artificial intelligence in unmanned aerial vehlice industry

2021 ◽  
Author(s):  
Adam Buday ◽  
◽  
Viliam Ažaltovič
Keyword(s):  
Artificial Intelligence ◽  
Data Exchange ◽  
Path Following ◽  
Advantages And Disadvantages ◽  
Detection And Tracking ◽  
Technical Requirements ◽  
Current State ◽  
The Future ◽  
Solution Methods ◽  
Artificial Intelligence Systems

The aim of this paper is the analysis of the contemporary state of implementation of artificial intelligence in the area of unmanned aerial vehicles (UAV), and a proposal of further use of artificial intelligence systems in this area in the future. We analyse three essential areas in which artificial intelligence systems are currently being implemented to some extend – path following, object detection and tracking, and anti—collision systems. In each mentioned area we apply different solution methods, technical requirements, but also advantages and disadvantages of those solutions. We present an overview of artificial intelligence as a scientific branch. Finally, we present an overview of how artificial intelligence in the field of UAV could be implemented in the future, based on an analysis of the current state and direction of research and development in the present. We describe the possibilities of use artificial intelligence systems in two areas that are currently receiving the most attention at concept level, namely the flight of autonomous UAV swarms and the improvement of communication and data exchange between individual UAVs using artificial intelligence.

HYDRODYNAMIC THRUST BEARINGS WITH POLYMER LINING

Tribologia ◽  
2016 ◽  
Vol 268 (4) ◽  
pp. 225-237 ◽  
Author(s):  
Michał WODTKE
Keyword(s):  
Polymeric Materials ◽  
Industrial Applications ◽  
Hydrodynamic Bearings ◽  
Thrust Bearings ◽  
Sliding Surfaces ◽  
Current State ◽  
Tilting Pad ◽  
History Of ◽  
Bearing Design ◽  
Experimental Researches

Polymeric linings of sliding surfaces of the hydrodynamic bearings have been used successfully for over 50 years. Despite of their long history of operation and research, they have not become widespread in industrial applications. This fact may be surprising, considering the conclusions that have been published concerning bearing operation and design. This paper summarizes the current state of the art of the tilting-pad thrust bearings with a polymer lining of pad sliding surfaces. Bearing design and the most commonly used polymeric materials are described. The results of the latest theoretical and experimental researches by both bearing manufacturers and at scientific centres are presented. Observed properties of the bearings with polymer lining were compared to the properties of the bearings covered with Babbitt, which is the most frequently material used as lining for hydrodynamic bearings.

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