scholarly journals Multicriteria optimal selection of a hydraulic cylinder for drive mechanisms

2021 ◽  
Vol 49 (2) ◽  
pp. 501-510
Author(s):  
Rosen Mitrev ◽  
Todor Todorov
Keyword(s):  
Hydraulic Cylinder ◽  
Objective Functions ◽  
Nonlinear Constrained Optimization ◽  
Optimization Task ◽  
Vector Closure ◽  
Force Moment ◽  
Multiobjective Design ◽  
Mixed Variable ◽  
Functional Purpose ◽  
Selection Of

The paper reports the optimization synthesis of a hydraulically actuated drive mechanism. A mathematical model of the mechanism using vector closure equations is developed. Based on the functional purpose of the mechanism, a set of geometric and force/moment requirements are defined which must be met by a proper selection of a standardized hydraulic cylinder and its points of attachment. A multiobjective design optimization task is defined with three objective functions whose minimum is searched - the mass of the hydraulic cylinder, the squared total deviation of the developed by the hydraulic cylinder moments from the predefined values of the external moments and the force in the hydraulic cylinder. The defined multiobjective optimization task is considered as a mixed variable nonlinear constrained optimization problem containing 5 continuous and 2 discrete variables and the multistage Monte Carlo method is used for its solution. Using different weighting schemes several Pareto-optimal compromise solutions are obtained.

A new representation for a robot grasping quality measure

Robotica ◽  
1995 ◽  
Vol 13 (3) ◽  
pp. 287-295 ◽  
Author(s):  
Venugopal K. Varma ◽  
Uri Tasch
Keyword(s):  
Objective Function ◽  
Material Properties ◽  
Graphical Representation ◽  
Contact Forces ◽  
Geometric Constraints ◽  
Objective Functions ◽  
Finger Force ◽  
Finger Forces ◽  
Robot Grasping ◽  
Selection Of

SummaryWhen an object is held by a multi-fingered hand, the values of the contact forces can be multivalued. An objective function, when used in conjunction with the frictional and geometric constraints of the grasp, can however, give a unique set of finger force values. The selection of the objective function in determining the finger forces is dependent on the type of grasp required, the material properties of the object, and the limitations of the röbot fingers. In this paper several optimization functions are studied and their merits highlighted. The paper introduces a graphical representation of the finger force values and the objective functions that enable one to select and compare various grasping configurations. The impending motion of the object at different torque and finger force values are determined by observing the normalized coefficient of friction plots.

scholarly journals Performance of Static Iot Networks using RPL Objective Functions

2019 ◽  
Vol 8 (4) ◽  
pp. 8972-8977 ◽  
Keyword(s):  
Objective Function ◽  
Routing Protocol ◽  
Routing Algorithms ◽  
Transmission Protocol ◽  
Objective Functions ◽  
Lossy Networks ◽  
Hop Count ◽  
Efficient Data ◽  
Selection Of ◽  
Better Than

Internet of Things, abbreviated as IoT is a network used mainly for the communication where different devices are connected for the retrieval, examination and execution of the necessary task. One of IoT’s biggest challenge is that, they are resource-constrained. Hence, it is essential to use an efficient data transmission protocol for routing. An effective routing protocol for static IoT network is the Routing protocol for Low Power and Lossy Networks (RPL). It is essential to assess the effectiveness of the RPL with the selection of best objective function for different static model. In this paper, the performance of different routing algorithms is compared in connection with different static topologies. Hence, the objective function’s performance is compared for different topologies i.e., Butterfly, Ring and Umbrella topologies. We consider two objective functions: namely Minimum Rank with Hysteresis Objective Function (MRHOF) and Objective Function Zero (OF0). MRHOF considers Expected Transmission Count (ETX) as its metric and the metric considered under OF0 is hop count. It is observed that the objective function OF0 performs better than MRHOF for the metric of energy and successful receiving of data.

scholarly journals THE STATIC OPTIMIZATION TASK OF OPTIMAL DESIGN OF NONLINEAR ELECTRONIC SCHEME

2019 ◽  
pp. 109-115
Author(s):  
Didmanidze Ibraim ◽  
Donadze Mikheil
Keyword(s):  
Optimal Design ◽  
Optimality Criteria ◽  
Pareto Optimal Solutions ◽  
Optimal Solutions ◽  
Design Task ◽  
Optimization Task ◽  
Minimum Capacity ◽  
Optimal Values ◽  
The Given ◽  
Selection Of

The article deals with such an important selection of the elements of electronic scheme of the given configuration, when the certain requirements of technical task are satisfied and at the same time the selected optimality criteria reach the extreme value. The gives task has been solved by the method of one-criterion optimization, in particular, the method of center gravity. To formalize the given scheme we have compiled a mathematical model of optimization, which considers the requirements of technical task. The optimal design task of the presented electronic scheme was brought to the task of multi criteria optimization. The computational experiments have been resulted in the Pareto-optimal solutions, from which there was selected a compromise on that corresponds to the minimum capacity, required by the scheme. According to the optimal values of resistors, we have conducted a computerized analysis of the transient process of the given electronic scheme with the help of a computer program Electronics Workbench.

scholarly journals A Comparison of Ensemble and Dimensionality Reduction DEA Models Based on Entropy Criterion

Algorithms ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 232
Author(s):  
Parag C. Pendharkar
Keyword(s):  
Dimensionality Reduction ◽  
Returns To Scale ◽  
Data Envelopment ◽  
Objective Functions ◽  
High Entropy ◽  
Selection Of Variables ◽  
Dea Models ◽  
Entropy Criterion ◽  
Selection Of ◽  
Normally Distributed

Dimensionality reduction research in data envelopment analysis (DEA) has focused on subjective approaches to reduce dimensionality. Such approaches are less useful or attractive in practice because a subjective selection of variables introduces bias. A competing unbiased approach would be to use ensemble DEA scores. This paper illustrates that in addition to unbiased evaluations, the ensemble DEA scores result in unique rankings that have high entropy. Under restrictive assumptions, it is also shown that the ensemble DEA scores are normally distributed. Ensemble models do not require any new modifications to existing DEA objective functions or constraints, and when ensemble scores are normally distributed, returns-to-scale hypothesis testing can be carried out using traditional parametric statistical techniques.

scholarly journals Optimization of Nonspherical Gold Nanoparticles for Photothermal Therapy

2019 ◽  
Vol 9 (20) ◽  
pp. 4300
Author(s):  
Paerhatijiang Tuersun ◽  
Xiayiding Yakupu ◽  
Xiang’e Han ◽  
Yingzeng Yin
Keyword(s):  
Gold Nanoparticles ◽  
Refractive Index ◽  
Photothermal Therapy ◽  
Therapeutic Agents ◽  
Tissue Type ◽  
Excitation Wavelength ◽  
Objective Functions ◽  
Design Tolerance ◽  
T Matrix ◽  
Selection Of

Previous investigations devoted to the optimization of nonspherical gold nanoparticles for photothermal therapy (PTT) encountered two issues, namely, the appropriate selection of objective functions and the processing of particle random orientations. In this study, these issues were resolved, and accurate optimization results were obtained for the three typical nonspherical gold nanoparticles (nanospheroid, nanocylinder, and nanorod) by using the T-matrix method. The dependence of the optimization results on the excitation wavelength and the refractive index of tissue was investigated. Regardless of the excitation wavelength and tissue type, gold nanospheroids were found to be the most effective therapeutic agents for PTT. The light absorption ability of optimized nanoparticles could be enhanced by using a laser with a longer wavelength. Finally, the design tolerance for the different sizes of nanoparticles was provided.

Computer Aided Design of Manufacturing of Anchors and Formulation of the Optimization Task for in Use Properties

2013 ◽  
Vol 554-557 ◽  
pp. 372-382
Author(s):  
Mariusz Skóra ◽  
Stanislaw Weglarczyk ◽  
Jan Kusiak ◽  
Maciej Pietrzyk
Keyword(s):  
Computer Aided Design ◽  
Dimensional Accuracy ◽  
Influence Of Process Parameters ◽  
Rheological Models ◽  
Optimization Task ◽  
Multi Stage ◽  
Bainitic Steels ◽  
Computer Aided ◽  
Aided Design ◽  
Selection Of

Computer aided design of the manufacturing technology for anchors is presented in the paper. Evaluation of applicability of various materials for anchors, as well as analysis of the influence of process parameters on the in use properties of product, were the objectives of the research. In the material part, bainitic steels were considered as an alternative for the commonly used C-Mn steels. Possibility of elimination of the heat treatment was evaluated. Rheological models for the investigated steels were developed and implemented into the finite element code for simulations of drawing and multi stage forging. Criteria for the selection of the best manufacturing chain composed dimensional accuracy, tool life and product properties. Industrial trials were performed for the selected cycle and the efficiency of this cycle was evaluated. Finally, simulations of the in use behaviour of the anchor-concrete joint were performed. On the basis of the simulations the optimization task using strength of the joint as the objective function was formulated

The Supplying Chain Scheduling with Outsourcing and Transportation

2017 ◽  
Vol 34 (02) ◽  
pp. 1750009 ◽  
Author(s):  
Jianfeng Ren ◽  
Guo Sun ◽  
Yuzhong Zhang
Keyword(s):  
Supply Chain ◽  
Approximation Algorithm ◽  
Single Machine ◽  
Complexity Analysis ◽  
Weighted Sum ◽  
Objective Functions ◽  
Supply Chain Scheduling ◽  
Total Cost ◽  
Scheduling Model ◽  
Selection Of

In this paper, we address a supply chain scheduling model with outsourcing and transportation. A job can be scheduled either on a single machine at a manufacturer’s plant or outsourced to a subcontractor. We assume that there are a sufficient number of vehicles at the manufacturer and the subcontractor such that each completed job can be transported to its customer immediately. For a given set of jobs, the decisions we need to make include the selection of jobs to be outsourced and the schedule of all the jobs. When the objective functions are to minimize the weighted sum of common scheduling measures and the total cost, we present their complexity analysis and a [Formula: see text]-approximation algorithm for the second problem.

scholarly journals Experimental Study on Friction of Hydraulic Cylinder in Different Sealing Systems

2018 ◽  
Vol 153 ◽  
pp. 06012
Author(s):  
Ke Ma ◽  
Jiawei Wang ◽  
Le Gu
Keyword(s):  
Experimental Study ◽  
Hydraulic Cylinder ◽  
Test System ◽  
Experimental Results ◽  
Testing System ◽  
Data Support ◽  
Selection Of

The friction of the hydraulic cylinder mainly comes from the sealing part, the existence of friction leads the wear of the seal. In view of the serious impact of the damage of the seal on the hydraulic cylinder, a set of sealing test system was designed, for the purpose of investigation and analysis on the performance of different sealing kit configuration, in terms of friction with given hydraulic medium. In this paper, there will be the introduction of the principles, constitutions and functions of the testing system. The experimental results provide data support for the design and selection of sealing system of the hydraulic cylinder.

scholarly journals BATH-HOUSES IN THE PLANNING STRUCTURE OF ANCIENT KYIV-PODIL

2017 ◽  
pp. 129-139
Author(s):  
Serhiy Taranenko
Keyword(s):  
City Planning ◽  
Scientific Literature ◽  
Old Russian ◽  
Wooden Structure ◽  
Ancient Times ◽  
Mass Development ◽  
The City ◽  
Functional Purpose ◽  
Selection Of

The article presents archaeologically fixed objects of wooden architecture of ancient times in Podil Kyiv, which scientists first interpreted as baths. Although there have been attempts in the national scientific literature to interpret the structures as baths (a monumental stone building of the XI century in the yard of the Kyiv Metropolitan, a wooden structure on the site 34 in Petrovsky's estate), first, these interpretations provoked debates. Secondly, they involved data only from Upper Kyiv - there was no case of identifying as a bath an archaeologically fixed object of wooden architecture in Podil. In the article, based on the analysis of available written, ethnographic and archaeological sources, the author proves the possibility of the existence of similar structures in the largest area of ​​Ancient Kyiv.The author addresses several issues regarding the mass development and planning structure of the ancient Russian hem. The first is the selection of more than 300 fixed objects of wooden architecture of this period, actually a bath. In doing so, it is proposed to use the technique of Khoroshov, which he proposed and implemented at the excavations of Ancient Novgorod. The second question concerns the revision and re-interpretation of the functional purpose of the investigated objects of ancient Russian architectural architecture recorded at the hem of Kyiv. Three buildings of the XII century are presented for consideration. (building No. 4, Obolonskaya St., 4, 1989, building No. 1, Pochayninska St., 27/44, 2003, building No. 8, Nizhniy Val St., 43, 1989), which the author proposes considered as baths that were part of the city planning structure. The author states that confirmation of the existence of bath-houses will allow to investigate the objects related to hygiene in the Old Rus and to expand not only the life of ancient Kyiv significantly. Also, it will be possible to make adjustments to the general reconstructions of the ordinary old-Russian manor and quarter.

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