Variable Control Setting to Enhance Rail Vehicle Braking Safety

2020 ◽  
Author(s):  
Sundar Shrestha ◽  
Maksym Spiryagin ◽  
Qing Wu
Keyword(s):  
Control Algorithm ◽  
Adhesion Force ◽  
Environmental Parameters ◽  
Vehicle Speed ◽  
Rail Vehicle ◽  
Potential Capacity ◽  
Braking Distance ◽  
Proper Definition ◽  
Definition Of ◽  
Adhesion Condition

Abstract Train braking technology needs to be advanced corresponding to the vehicle advancement to fully utilize the benefits of the potential capacity, efficiency and to ensure safety. The effectiveness of the braking changes as the friction condition at the wheel-rail interface and speed of rail vehicle change. The conventional brake control systems do not differentiate these changes in conditions and consider a constant slip reference. To overcome this issue, a new control algorithm for a wheel slide protection device incorporated in the electronically controlled pneumatic brake system has been proposed. Unlike conventional controllers, the proposed controller is responsive to the change of operational and environmental parameters between wheel and rail. It is designed based on multiple modes shifting during operations as the friction conditions change which allows to utilize the maximum adhesion available and to prevent the occurrence of sliding. The control algorithm is developed in a modular approach, where the first module identifies the adhesion condition at the wheel-rail interface. The result from the first module is further implemented in the second module to search for the optimum slip range for that adhesion condition and vehicle speed. For numerical simulation, a wagon model considering in-train forces is developed. The adhesion force is modeled by a proper definition of an adhesion-creep characteristics curve achieved from measured data. The comparison between the proposed control algorithm and the conventional algorithm suggests that the proposed control algorithm can optimally utilize available adhesion between wheel and rail to ensure shorter braking distance while maintaining vehicle stability.

Simultaneous heat and mass transfer during evaporation from a film of liquid into the turbulent gas

1982 ◽  
Vol 47 (3) ◽  
pp. 766-775 ◽  
Author(s):  
Václav Kolář ◽  
Jan Červenka
Keyword(s):  
Experimental Data ◽  
Mass Transfer ◽  
Liquid Film ◽  
Heat And Mass Transfer ◽  
Driving Forces ◽  
Proper Definition ◽  
Definition Of ◽  
Simultaneous Heat ◽  
Theory And Experiment

The paper presents results obtained by processing a series of published experimental data on heat and mass transfer during evaporation of pure liquids from the free board of a liquid film into the turbulent gas phone. The data has been processed on the basis of the earlier theory of mechanism of heat and mass transfer. In spite of the fact that this process exhibits a strong Stefan's flow, the results indicate that with a proper definition of the driving forces the agreement between theory and experiment is very good.

Speed regulation control of tractors’ new dual-flow transmission system based on slip rate resistance classification

2021 ◽  
pp. 095440702110105
Author(s):  
Guang Xia ◽  
Yan Xia ◽  
Xiwen Tang ◽  
Linfeng Zhao ◽  
Baoqun Sun
Keyword(s):  
Control Strategy ◽  
Control Algorithm ◽  
Production Efficiency ◽  
Sliding Mode ◽  
Slip Rate ◽  
Speed Control ◽  
Working Environment ◽  
Vehicle Speed ◽  
Speed Change ◽  
Simulation Results

Fluctuations in operation resistance during the operating process lead to reduced efficiency in tractor production. To address this problem, the project team independently developed and designed a new type of hydraulic mechanical continuously variable transmission (HMCVT). Based on introducing the mechanical structure and transmission principle of the HMCVT system, the priority of slip rate control and vehicle speed control is determined by classifying the slip rate. In the process of vehicle speed control, the driving mode of HMCVT system suitable for the current resistance state is determined by classifying the operation resistance. The speed change rule under HMT and HST modes is formulated with the goal of the highest production efficiency, and the displacement ratio adjustment surfaces under HMT and HST modes are determined. A sliding mode control algorithm based on feedforward compensation is proposed to address the problem that the oil pressure fluctuation has influences on the adjustment accuracy of hydraulic pump displacement. The simulation results of Simulink show that this algorithm can not only accurately follow the expected signal changes, but has better tracking stability than traditional PID control algorithm. The HMCVT system and speed control strategy models were built, and simulation results show that the speed control strategy can restrict the slip rate of driving wheels within the allowable range when load or road conditions change. When the tractor speed is lower than the lower limit of the high-efficiency speed range, the speed change law formulated in this paper can improve the tractor speed faster than the traditional rule, and effectively ensure the production efficiency. The research results are of great significance for improving tractor’s adaptability to complex and changeable working environment and promoting agricultural production efficiency.

WoCoVA consensus on the clinical use of in-line filtration during intravenous infusions: Current evidence and recommendations for future research

2021 ◽  
pp. 112972982198916
Author(s):  
Ton Van Boxtel ◽  
Mauro Pittiruti ◽  
Annemarie Arkema ◽  
Patrick Ball ◽  
Giovanni Barone ◽  
...  
Keyword(s):  
Potential Benefit ◽  
Scientific Evidence ◽  
Venous Access ◽  
Current Evidence ◽  
Future Research ◽  
Global Awareness ◽  
Current State ◽  
Intravenous Infusions ◽  
Proper Definition ◽  
Definition Of

The need for filtering intravenous infusions has long been recognized in the field of venous access, though hard scientific evidence about the actual indications for in-line filters has been scarce. In the last few years, several papers and a few clinical studies have raised again this issue, suggesting that the time has come for a proper definition of the type of filtration, of its potential benefit, and of its proper indications in clinical practice. The WoCoVA Foundation, whose goal is to increase the global awareness on the risk of intravenous access and on patients’ safety, developed the project of a consensus on intravenous filtration. A panel of experts in different aspects of intravenous infusion was chosen to express the current state of knowledge about filtration and to indicate the direction of future research in this field. The present document reports the final conclusions of the panel.

scholarly journals Effect of Harvest Date on Mango (Mangifera Indica L. Cultivar Osteen) Fruit’s Qualitative Development, Shelf Life and Consumer Acceptance

Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 811
Author(s):  
Giuseppe Gianguzzi ◽  
Vittorio Farina ◽  
Paolo Inglese ◽  
Maria Gloria Lobo Rodrigo
Keyword(s):  
Management Practices ◽  
Mangifera Indica ◽  
Storage Period ◽  
Environmental Parameters ◽  
Internal Quality ◽  
Harvest Management ◽  
Post Harvest ◽  
Full Flowering ◽  
Constant Quality ◽  
Definition Of

The qualitative characteristics of mango fruits change throughout their development process and are also influenced by their duration. Harvesting at different times after the fruit set affects external and internal quality and the post-harvest behavior and management possibilities of the fruits. The objective of this study was to assess the evolution of the most important physicochemical and organoleptic parameters of cv. Osteen fruits concern the length of their stay on the plant and also to their post-harvest management. For this reason, fruits were harvested progressively in ten pickings. The study showed that mango fruits that are kept on the tree reach the best quality traits, corresponding to their physiological maturation. The length of the storage period needed to reach the consumption point varies greatly according to the harvesting moment and to the different environmental parameters, which also affect the organoleptic and physicochemical quality of the fruits. The number of days after full flowering were confirmed to be the primary information to consider when planning harvest with commercial use of the fruit, but interesting indications can be acquired through the definition of non-destructive (hardness, color) or destructive (dry matter) parameters. The data collected help improve mango fruit′s post-harvest management practices, to provide a product with constant quality and homogeneity to the consumer.

Artificially making Lifeform

2021 ◽  
Vol 9 (10) ◽  
pp. 1290-1295
Author(s):  
Souvik Das
Keyword(s):  
Medical Community ◽  
Programming Algorithm ◽  
The Public ◽  
For Profit ◽  
Not For Profit ◽  
Funding Agencies ◽  
Proper Definition ◽  
Inanimate Matter ◽  
Living Organisms ◽  
Definition Of

Abstract: The word ‘life’ is a mysterious word with a chart of attributes that have neither been completed nor has been agreed upon by the race of humans. Probably the proper definition of life is impossible to identify for humans (the proof for this claim is given later) but the handbook to the secret shall be updated till the end, thanks to the inquisitive attitude of humans. For this piece, we shall adopt the description from the professional medical community of today. Though this topic falls midway between science and philosophy, this project is strictly technical. To quote dictionary.com, Life is the condition that distinguishes organisms from inorganic objects and dead organisms, being manifested by growth through metabolism, reproduction and the power of adaptation to environment- through changes originating internally; cambridge.com teaches Life is the period between birth and death, or the experience or state of being alive; medicaldictionary.thefreedictionary.com states Life is the property or quality that distinguishes living organisms from dead organisms and inanimate matter, manifested in functions such as metabolism, growth, reproduction and response to stimuli or adaptation to the environment originating from within the organisms. There are several other definitions but to summarize, we can safely state that though the concept is somewhat vague, we could indeed point out some common principles. We shall, in this project, try to replicate the characteristics so as to attain life in medical terms. (The order does not base upon importance of the listed character since the characters, all of them are absolute essentials and cannot possibly be categorized as more or less important). 1) Metabolism 2) Growth 3) Adaptability 4) Birth 5) Death 6) Self-stimulated response to environment 7) Reproduction 8) Can sustain self without foreign intervention Keywords: artificial, life, intelligence, computer, programming, algorithm This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

scholarly journals Lean & Green on Industry 4.0 Context – Contribution to Understand L&G Drivers and Design Principles

2021 ◽  
Vol 6 (5) ◽  
pp. 1214-1229
Author(s):  
Lenin John ◽  
Manuel Sampayo ◽  
Paulo Peças
Keyword(s):  
Industry 4.0 ◽  
Research Work ◽  
Design Principles ◽  
Manufacturing Companies ◽  
Bottom Line ◽  
Industrial Firms ◽  
Systems Implementation ◽  
Sustainability Concept ◽  
Proper Definition ◽  
Definition Of

The purpose of this paper is to demonstrate how the implementation of Lean & Green (L&G) in an Industry 4.0 (I4.0) environment can enhance the potential impact of the L&G approach and help manufacturing companies moving towards higher operational and sustainable performances. The research work developed here shows that although a proper definition of L&G is neither exposed worldwide nor explicitly implemented under that name, the current industrial firms are deeply concerned about the demanding challenge of keeping businesses flexible and agile without forgetting strategies to minimize the acceleration of climate change. So, one contribution of this paper is the identification and characterization of L&G drivers and design principles, supporting a robust and well-informed L&G systems implementation. As inferred from the research work, this challenge demands high quality and updated data together with assertive information. Thus, the implementation of L&G in I4.0 contexts is the answer to overcome the identified barriers. Likewise, an L&G system contributes to overcoming the challenges of I4.0 implementation regarding the triple bottom line sustainability concept. Consequently, another contribution of this paper is to depict why an L&G system performs better in the I4.0 context.

scholarly journals Reconstructing the Contours of the Copyright Originality and Idea- Expression Doctrines Regarding the Right to Deny Access to Works

2014 ◽  
Vol 1 (4) ◽  
pp. 921-940
Author(s):  
Michael D. Murray
Keyword(s):  
First Amendment ◽  
Freedom Of Expression ◽  
Cultural Knowledge ◽  
Fair Use ◽  
Digital Revolution ◽  
Content Development ◽  
Proper Definition ◽  
Definition Of ◽  
Access To Knowledge ◽  
The Right

ccess to innovative scientific, literary, and artistic content has never been more important to the public than now, in the digital age. Thanks to the digital revolution carried out through such means as super-computational power at super-affordable prices, the Internet, broadband penetration, and contemporary computer science and technology, the global, national, and local public finds itself at the convergence of unprecedented scientific and cultural knowledge and content development, along with unprecedented means to distribute, communicate, and access that knowledge. This Article joins the conversation on the Access-to-Knowledge, Access-to- Medicine, and Access-to-Art movements by asserting that the copyright restrictions affecting knowledge, innovation, and original thought implicate copyright’s originality and idea-expression doctrines first and fair use doctrine second. The parallel conversation in copyright law that focuses on the proper definition of the contours of copyright as described in the U.S. Supreme Court’s most recent constitutional law cases on copyright—Feist, Eldred, Golan, and Kirtsaeng—interprets the originality and idea-expression doctrines as being necessary for the proper balance between copyright protection and First Amendment freedom of expression. This Article seeks to join together the two conversations by focusing attention on the right to access published works under both copyright and First Amendment law. Access to works is part and parcel of the copyright contours debate. It is a “first principles” question to be answered before the question of manipulation, appropriation, or fair use is contemplated. The original intent of the Copyright Clause and its need to accommodate the First Amendment freedom of expression support the construction of the contours of copyright to include a right to access knowledge and information. Therefore, the originality and idea-expression doctrines should be reconstructed to recognize that the right to deny access to published works is extremely limited if not non-existent within the properly constructed contours of copyright.

scholarly journals Ki vagyok én? - Szárnyas fejvadász 2049

2020 ◽  
Vol 10 (21) ◽  
pp. 307-312
Author(s):  
Pál Gerdesits
Keyword(s):  
Michel Foucault ◽  
Jacques Derrida ◽  
Self Identity ◽  
Ferdinand De Saussure ◽  
Blade Runner ◽  
Jean Paul ◽  
Proper Definition ◽  
Definition Of ◽  
Philosophical Questions

My essay focuses on the ontological crisis articulated in the film Blade Runner 2049, the sequel for Ridley Scott’s Blade Runner. This film is based on the conflict between humans and androids called replicants who would like to live equally to humans. In my opinion the root of their opposition lies on the inability to give a proper definition of what we normally call ‘human’. In this writing I present and analyse the nature of this conflict and also the philosophical questions (representation, freedom, self-identity etc.) arising from it based on the ideas of philosophers like Michel Foucault. Jean-Paul Sartre, Jacques Derrida and Ferdinand de Saussure.

scholarly journals Updated definitions on piezophily as suggested by hydrostatic pressure dependence on temperature

2020 ◽  
Author(s):  
Alberto Scoma
Keyword(s):  
Hydrostatic Pressure ◽  
Deep Sea ◽  
Ambient Pressure ◽  
Environmental Parameters ◽  
Microbial Life ◽  
Deep Waters ◽  
Microbial Response ◽  
Definition Of ◽  
Substrate Ph ◽  
Cell Functionality

AbstractMicrobial preference for elevated hydrostatic pressure (HP) is a recognized key feature of environmental and industrial processes. HP effects on macromolecules and, consequently, cell functionality has been accurately described in the last decades. While there is little debate about the importance of HP in shaping microbial life, a systematic definition of microbial preference for increased HP is missing. The lack of a consensus about ‘true’ piezophiles, and ‘low’ or ‘high’ HP levels, has deleterious repercussions on microbiology and biotechnology. As certain levels are considered ‘low’ they are not applied to assess microbial activity. Most microorganisms collected in deep waters or sediments have not been tested (nor isolated) using the corresponding HP at which they were captured. Microbial response to HP is notoriously dependent on other environmental parameters, most notably temperature, but also on availability of nutrients, growth substrate, pH and salinity. This implies that countless isolates retrieved from ambient pressure conditions may very well require increased HP to grow optimally, as already demonstrated in both Archaea and Bacteria.In the present study, I collected the data from described piezophilic isolates and used the fundamental correlation existing between HP and temperature, as first suggested in seminal works by Yayanos, to update the definition of piezophiles. Thanks to the numerous new piezophilic isolates available since such seminal studies, the present analysis brings forward updated definitions which concern 1) the actual beginning of the piezosphere, the area in the deep sea where piezophiles thrive; 2) the HP thresholds which should be considered low, medium and high HP, and their implications for experimental design in Microbiology; and 3) the nature of obligate piezophiles and their location in the deep sea.

scholarly journals Innovative start-ups and young entrepreneurs: Definition of venture capital and findings from Switzerland

2017 ◽  
Vol 7 (1) ◽  
pp. 75-81
Author(s):  
Simon Zaby
Keyword(s):  
Venture Capital ◽  
Success Factors ◽  
Total Sample ◽  
Venture Capitalists ◽  
Flow Of Funds ◽  
Start Up ◽  
Capital Financing ◽  
Proper Definition ◽  
Definition Of ◽  
Start Ups

This paper aims to investigate success factors of innovative start-up firms from the perspective of young start-up managers. Which key factors did they experience before and since the foundation of their company? The experience from the quite young Swiss start-up scene pro-vides important insights to entrepreneurs and policy-makers in emerging countries that cur-rently face the necessity of building up a start-up environment. One part of the data has been collected by the author, the other part originates from the Swiss Venture Capital Database (total sample size: 306). The results show a significant role of venture capital financing for the success of innovative start-ups. Interestingly, this is to some extent because the start-ups see various additional benefits from venture capitalists involved in their firm. Thus, the findings shed new light on a proper definition of venture capital that should not solely focus on the flow of funds.

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