scholarly journals A model for determining the time of pointing a grip-cutting device of feller buncher machines on a growing tree

2021 ◽  
Author(s):  
А.В. Андронов ◽  
И.А. Зверев ◽  
О.А. Михайлов ◽  
Г.С. Тарадин
Keyword(s):  
Mathematical Model ◽  
Average Distance ◽  
Hydraulic Cylinder ◽  
Technological Equipment ◽  
Maximum Time ◽  
Cylinder Piston ◽  
Experienced Operator ◽  
Time Required ◽  
The Way

Исследование посвящено нахождению аналитической математической модели по определению времени наведения захватно-срезающего устройства на растущее дерево. В качестве известных параметров используются конструктивные размеры технологического оборудования, снятые с компоновочно-кинематических схем валочно-пакетирующих машин, требуемая высота пня и среднее расстояние между деревьями пасики. Поиск требуемой модели кратко можно разделить на несколько последовательных этапов: нахождение пути, который пройдет шток гидроцилиндра привода стрелы, и по известной формуле скорости перемещения поршня гидроцилиндра находится время на подвод стрелы к дереву; нахождение пути, который пройдет шток гидроцилиндра привода рукояти; нахождение пути, который пройдет шток гидроцилиндра привода наклона захватно-срезающего устройства; нахождение пути, который пройдет шток гидроцилиндра привода рычагов захвата в процессе раскрытия. Сумма времени на подвод каждого из элементов технологического оборудования и есть время на наведение, присущее неопытному оператору, в случае опытного оператора время на наведение захватно-срезающего устройства к дереву определяется максимальным временем одного из компонентов. The research is devoted to finding an analytical mathematical model for determining the aiming time of a feller head on a growing tree. As the known parameters are used. The design dimensions of the technological equipment, taken from layout and kinematic diagrams of feller-buncher machines, the required stump height and the average distance between the trees of the windrow. The search for the required model can be briefly divided into several successive steps: finding the path that the hydraulic cylinder rod of the boom drive will take and by the known formula of speed of movement of the hydraulic cylinder piston is time to bring the boom to the tree; finding the way which the rod of the hydraulic cylinder of the arm drive; to find the path which the hydraulic cylinder rod of the tilt of the feller head; finding the path which the hydraulic cylinder rod for the arm actuator will take during the opening. The sum of the time for supplying each of the elements of technological equipment is the time required for the orientation, which is characteristic for a nonexperienced operator. In case of an experienced operator the time for setting the feller head to the tree is determined by the maximum time of one of the components.

Synergy of surface textures on a hydraulic cylinder piston

2019 ◽  
Vol 14 (4) ◽  
pp. 424-429 ◽  
Author(s):  
Ying Zhang ◽  
Liangcai Zeng ◽  
Zhenpeng Wu ◽  
Xianzhong Ding ◽  
Kuisheng Chen
Keyword(s):  
Hydraulic Cylinder ◽  
Surface Textures ◽  
Cylinder Piston

An Improved Mathematical Model of Galton Board With Velocity-Dependent Restitution

2017 ◽  
Vol 12 (6) ◽  
Author(s):  
Auni Aslah Mat Daud
Keyword(s):  
Mathematical Model ◽  
Random Walk ◽  
Symbolic Dynamics ◽  
Coefficient Of Restitution ◽  
Dynamics Analysis ◽  
The Novel ◽  
Francis Galton ◽  
The Way

A Galton board is an instrument invented in 1873 by Francis Galton (1822–1911). It is a box with a glass front and many horizontal nails or pins embedded in the back and a funnel. Galton and many modern statisticians claimed that a lead ball descending to the bottom of the Galton board would display random walk. In this study, a new mathematical model of Galton board is developed, to further improve three very recently proposed models. The novel contribution of this paper is the introduction of the velocity-dependent coefficient of restitution. The developed model is then analyzed using symbolic dynamics. The results of the symbolic dynamics analysis prove that the developed Galton board model does not behave the way Galton envisaged.

MyrrorBot : A Digital Assistant Based on Holistic User Models for Personalized Access to Online Services

2021 ◽  
Vol 39 (4) ◽  
pp. 1-34
Author(s):  
Cataldo Musto ◽  
Fedelucio Narducci ◽  
Marco Polignano ◽  
Marco De Gemmis ◽  
Pasquale Lops ◽  
...  
Keyword(s):  
Natural Language ◽  
Information Needs ◽  
Effective Interaction ◽  
Personal Digital Assistant ◽  
User Profiling ◽  
Online Services ◽  
Intent Recognition ◽  
User Models ◽  
Time Required ◽  
The Way

In this article, we present MyrrorBot , a personal digital assistant implementing a natural language interface that allows the users to: (i) access online services, such as music, video, news, and food recommendation s, in a personalized way, by exploiting a strategy for implicit user modeling called holistic user profiling ; (ii) query their own user models, to inspect the features encoded in their profiles and to increase their awareness of the personalization process. Basically, the system allows the users to formulate natural language requests related to their information needs. Such needs are roughly classified in two groups: quantified self-related needs (e.g., Did I sleep enough? Am I extrovert? ) and personalized access to online services (e.g., Play a song I like ). The intent recognition strategy implemented in the platform automatically identifies the intent expressed by the user and forwards the request to specific services and modules that generate an appropriate answer that fulfills the query. In the experimental evaluation, we evaluated both qualitative (users’ acceptance of the system, usability) as well as quantitative (time required to complete basic tasks, effectiveness of the personalization strategy) aspects of the system, and the results showed that MyrrorBot can improve the way people access online services and applications. This leads to a more effective interaction and paves the way for further development of our system.

Analytical Study of Hydro-Pneumatic Processes for Gorlov's Power System

1994 ◽  
Vol 208 (1) ◽  
pp. 67-70
Author(s):  
A I Ryazanov
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Power System ◽  
Analytical Study ◽  
Model Tests ◽  
Air Pressure ◽  
Pneumatic Power ◽  
Time Required ◽  
The Mathematical Model

This paper describes the aerohydrodvnamics of processes in chambers of Gorlov's hydro-pneumatic power system. The mathematical model is developed to determine the main parameters of the processes: water and air velocities, air pressure in the chamber, the periods of time required to fill and empty the chambers and the output of energy during the cycle. The results obtained are in agreement with experimental data and model tests.

scholarly journals Speed-detachment tradeoff and its effect on track bound transport of single motor protein

2018 ◽  
Author(s):  
Mohd Suhail Rizvi
Keyword(s):  
Experimental Data ◽  
Random Walk ◽  
Power Law ◽  
Average Distance ◽  
Motor Protein ◽  
Fixed Duration ◽  
Biological Cells ◽  
Single Motor ◽  
Stochastic Nature ◽  
Time Required

AbstractThe transportation of the cargoes in biological cells is primarily driven by the motor proteins on filamentous protein tracks. The stochastic nature of the motion of motor protein often leads to its spontaneous detachment from the track. Using the available experimental data, we demonstrate a tradeoff between the speed of the motor and its rate of spontaneous detachment from the track. Further, it is also shown that this speed-detachment relation follows a power law where its exponent dictates the nature of the motor protein processivity. We utilize this information to study the motion of motor protein on track using a random-walk model. We obtain the average distance travelled in fixed duration and average time required for covering a given distance by the motor protein. These analyses reveal non-monotonic dependence of the motor protein speed on its transport and, therefore, optimal motor speeds can be identified for the time and distance controlled conditions.

scholarly journals Localization of a Power-Modulated Jammer

Sensors ◽  
2022 ◽  
Vol 22 (2) ◽  
pp. 646
Author(s):  
Pietro Tedeschi ◽  
Gabriele Oligeri ◽  
Roberto Di Pietro
Keyword(s):  
Mathematical Model ◽  
High Precision ◽  
Radio Channel ◽  
Localization Error ◽  
Constant Power ◽  
Shadowing Effect ◽  
Weak Shadowing ◽  
The Way

Jamming is a malicious radio activity that represents a dreadful threat when employed in critical scenarios. Several techniques have been proposed to detect, locate, and mitigate jamming. Similarly, counter-counter-jamming techniques have been devised. This paper belongs to the latter thread. In particular, we propose a new jammer model: a power-modulated jammer that defies standard localization techniques. We provide several contributions: we first define a new mathematical model for the power-modulated jammer and then propose a throughout analysis of the localization error associated with the proposed power-modulated jammer, and we compare it with a standard power-constant jammer. Our results show that a power-modulated jammer can make the localization process completely ineffective—even under conservative assumptions of the shadowing process associated with the radio channel. Indeed, we prove that a constant-power jammer can be localized with high precision, even when coupled with a strong shadowing effect (σ ≈ 6 dBm). On the contrary, our power-modulated jammer, even in the presence of a very weak shadowing effect (σ < 2 dBm), presents a much wider localization error with respect to the constant-power jammer. In addition to being interesting on its own, we believe that our contribution also paves the way for further research in this area.

scholarly journals Analysis of Platform Leveling Systems for Tracked Feller-Buncher Machines

Inventions ◽  
2021 ◽  
Vol 6 (4) ◽  
pp. 96
Author(s):  
Andronov Alexandr ◽  
Bacherikov Ivan ◽  
Zverev Igor
Keyword(s):  
Mathematical Model ◽  
Center Of Mass ◽  
Slope Angle ◽  
Hydraulic Cylinder ◽  
Second Stage ◽  
Modeling Methods ◽  
The Third ◽  
Support Reaction ◽  
Third Stage ◽  
The Stability

The study was devoted to the analysis of feller buncher platform leveling systems. The widespread use of these systems in the design of modern feller-buncher machines makes the study relevant to assess operational efficiency. The analysis was conducted in five stages using analytical and stochastic mathematical modeling methods. In the first stage, the existing layouts of alignment systems were analyzed from the position of force on the hydraulic cylinder rods of the platform tilt drive. The three-cylinder layout scheme, where the force on the hydraulic cylinder rod was 50…60% less than that on the two-cylinder layout, appeared to be the most expedient. In the second stage, a mathematical model for determining changes in the position of the center of mass of the feller-buncher depending on the inclination angle of the platform was derived. In the third stage, a mathematical model was derived for determining the limiting angle of slope of the terrain when the feller buncher moved up the slope. For this purpose, two calculation schemes were considered when the machine moved up the slope without and with a tilted platform. Zero support reaction on the front roller was taken as the stability criterion. In the fourth stage, a mathematical model for determining the limiting angle of slope of the terrain during the roll of the feller-buncher machine was obtained. In the fifth stage, the efficiency of the application of leveling systems was evaluated. A graph of the dependence of changes in the terrain slope angle on the platform slope angle was plotted, and a regression dependence for an approximate estimate was obtained. A regression analysis was also carried out, and dependencies were obtained to determine the weight of a feller-buncher with a leveling system and the added pressure on the ground caused by the increase in the weight of the base machine. The analysis of platform leveling systems showed the effectiveness of their application in the designs of feller-buncher machines, as it allows the machines to work on slopes with an inclination of 50…60% more than without them.

scholarly journals Warehouse Relayout Design with Weighted Distance Method to Minimize Time Travel

2020 ◽  
Vol 3 (1) ◽  
pp. 1-8
Author(s):  
Adi Firmansyah ◽  
Lukmandono Lukmandono
Keyword(s):  
Mathematical Model ◽  
Travel Time ◽  
Layout Design ◽  
Global Competition ◽  
Closing Time ◽  
Distance Method ◽  
Weighted Distance ◽  
Logistics Services ◽  
Time Required ◽  
Efficient Work

Global competition between companies is becoming increasingly stringent, resulting in companies having to understand their customers better. Customers no longer only need quality products, but also need excellent and timely service. To meet the desires of these consumers, the company must create an effective and efficient work system. PT IJS is a warehouse engaged in logistics services in the Perak area of Surabaya. One of the services provided by PT IJS is bonded warehouse logistic services. A bounded warehouse owned is currently not able to provide maximum service because there are still many late deliveries that do not send goods to the port, and there is a closing time that is detrimental to the customer. The length of the delivery process is due to several factors, one of which is a less effective warehouse layout. Travel time is the time required for a vehicle to carry out activities loading goods PT. IJS from arrival to exit the warehouse. The method weighted distance is a mathematical model used to evaluate the layout based on proximity factors. The design of the layout design by using the technique weighted distance produces an alternative layout that shows calculation travel time a shorter

Test Analysis of a Six-Wheel Hydraulic Active Suspension Control System

2012 ◽  
Vol 591-593 ◽  
pp. 1710-1714
Author(s):  
Wei Chen ◽  
Zhi Yao ◽  
Qing Bo Zhao ◽  
Tong Jian Wang
Keyword(s):  
Mathematical Model ◽  
Control System ◽  
Active Suspension ◽  
Hydraulic Cylinder ◽  
Suspension System ◽  
Quantitative Feedback Theory ◽  
Test Analysis ◽  
Suspension Control ◽  
System Robustness ◽  
Road Performance

In order to make the active hydraulic suspension system to adaptive the ground. Taking the asymmetric valve controlled hydraulic cylinder as actuators, a six wheels hydraulic active suspension was designed. It is difficult to analysis of the six wheels system. So this paper established the single wheel’s mathematical model to instead analysis of the whole system, designed QFT (Quantitative Feedback Theory) controller which can be a solution to the system robustness, researched the hydraulic active suspension system. The results show that it is good for tracking performance of the hydraulic cylinder which taking the asymmetric valve controlled as actuators, system responses timely and the controller can meet the controlling requirements. This hydraulic active suspension system can improve off-road performance of engineering vehicles.

Fast and Intelligent Antenna Design Optimization using Machine Learning

2021 ◽  
Vol 35 (11) ◽  
pp. 1350-1351
Author(s):  
Gopinath Gampala ◽  
C. J. Reddy
Keyword(s):  
Machine Learning ◽  
Mathematical Model ◽  
Design Optimization ◽  
Antenna Design ◽  
Convergence Criteria ◽  
Time Required

Traditional antenna optimization solves the modified version of the original antenna design for each iteration. Thus, the total time required to optimize a given antenna design is highly dependent on the convergence criteria of the selected algorithm and the time taken for each iteration. The use of machine learning enables the antenna designer to generate trained mathematical model that replicates the original antenna design and then apply optimization on the trained model. Use of trained model allows to run thousands of optimization iterations in a span of few seconds.

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