scholarly journals UNAMBIGUOUSNESS-AMBIGUITY OF PARAMETRIC OPTIMIZATION OF MOTOR-CAR SYSTEMS IN THE CONDITIONS OF CRITERIAL UNCERTAINTY

2020 ◽  
Vol 21 ◽  
pp. 5-23
Author(s):  
P. Hashchuk
Keyword(s):  
Fair Trade ◽  
Optimization Problem ◽  
Parametric Optimization ◽  
Arithmetic Mean ◽  
Trade Off ◽  
Step Process ◽  
One Dimensional ◽  
Real Process ◽  
All Solutions ◽  
The Ideal

Annotation. The general methodology of parametric optimization of systems is considered for two arbitrary cri-teria simultaneously. The so-called principle of expanding an optimization problem is proposed, which creates the basis for finding guaranteed unambiguous solutions, without resorting to artificial formal means of «collapse» of the two cri-teria into one. It turns out that a very common multiplicative criterion for so-called fair trade-off actually expresses the average geometric basic criteria. It is easy to reduce (lead down) it to additive. Therefore, it is certainly not known, why he should give preference to the arithmetic mean (after the appropriate coordinate) of the dimensions of the primary criteria. There are more subjective and far-fetched than objective and truthful in the criterion of a fair compromise.Perfection is a permanent process — it has a beginning but has no end. In that the new" perfections arise from time to time and each of them definitely use a certain time, then, of course, the process of perfection is a step-by-step process, an endless step to an unattainable ideal. This particular circumstance should be taken into account.Described algorithms for optimal search formally reproduce on a primitive model plane the real process of step-by-step improvement of all man-made - from acceptable to better... There are no examples when something was created immediately unconditionally optimally (and the ideal — at all not recognizable and therefore not embodied). At each step, one of the algorithms regulates minimizing the value of a single criterion, without affecting it, without changing the other. That is why there are no conflicts outside the attractor. Only within the attractor, for which the line (which is a one-dimensional attractor) rules on the model plane, the consistency disappears. Another algorithm combines a series of steps in each of which only one parameter varies, and the gain at the same time has both supporters of one perfection, and supporters of some other perfection. Consequently, there are no conflicts, until the algorithm does not attract the attractor, which this time is an area on a model plane, that is a two-dimensional attractor.Within the attractor, all solutions to the optimization problem is appropriate without a doubt, even advisable to consider completely equivalent. However, in fact, insurmountable subjectivism does not allow us to adhere to this idea (let's say, without the participation of any dictator).

scholarly journals Solution of the compromise optimization problem of network graphics on the criteria of uniform personnel loading and distribution of funds

2021 ◽  
Vol 1 (4(57)) ◽  
pp. 14-21
Author(s):  
Olena Domina
Keyword(s):  
Optimization Problem ◽  
Mathematical Planning ◽  
One Dimensional ◽  
Model Network ◽  
All Solutions ◽  
Network Schedule ◽  
Optimal Values ◽  
Input Variables ◽  
Point Of Intersection ◽  
Compromise Optimization

The object of research is a model network schedule for performing a complex of operations. One of the most problematic areas is the lack of a unified procedure that allows finding a solution to the problem of compromise optimization, for which the optimization criteria can have a different nature of the influence of input variables on them. In this study, such criteria are the criteria for the uniformity of the workload of personnel and the distribution of funds. Two alternative cases are considered: with monthly planning and with quarterly planning of allocation of funds and staff load. The methods of mathematical planning of the experiment and the ridge analysis of the response surface are used. The peculiarities of the proposed procedure for solving the problem of compromise optimization are its versatility and the possibility of visualization in one-dimensional form – the dependence of each of the alternative criteria on one parameter describing the constraints. The solution itself is found as the point of intersection of equally labeled ridge lines, which are curves that describe the locally optimal values of the output variables. The proposed procedure, despite the fact that it is performed only on a model network diagram, can be used to solve the trade-off optimization problem on arbitrary network graphs. This is due to the fact that the combination of locally optimal solutions in a parametric form on one graph allows visualizing all solutions to the problem. The results obtained at the same time make it possible to select early dates for the start of operations in such a way that, as much as possible, take into account possible difficulties due to the formation of bottlenecks at certain stages of the project. The latter may be due to the fact that for the timely execution of some operation, it may be necessary to combine two criteria, despite the fact that the possible costs may turn out to be more calculated and estimated as optimal.

Parameter study and optimization design of a hat oblique tunnel portal

2021 ◽  
pp. 095440972110140
Author(s):  
Zijian Guo ◽  
Tanghong Liu ◽  
Wenhui Li ◽  
Yutao Xia
Keyword(s):  
High Speed ◽  
Optimization Design ◽  
Pareto Front ◽  
Optimization Problem ◽  
Optimization Method ◽  
Design Parameters ◽  
Parameter Study ◽  
Buffer Structure ◽  
Tunnel Entrance ◽  
The Ideal

The present work focuses on the aerodynamic problems resulting from a high-speed train (HST) passing through a tunnel. Numerical simulations were employed to obtain the numerical results, and they were verified by a moving-model test. Two responses, [Formula: see text] (coefficient of the peak-to-peak pressure of a single fluctuation) and[Formula: see text] (pressure value of micro-pressure wave), were studied with regard to the three building parameters of the portal-hat buffer structure of the tunnel entrance and exit. The MOPSO (multi-objective particle swarm optimization) method was employed to solve the optimization problem in order to find the minimum [Formula: see text] and[Formula: see text]. Results showed that the effects of the three design parameters on [Formula: see text] were not monotonous, and the influences of[Formula: see text] (the oblique angle of the portal) and [Formula: see text] (the height of the hat structure) were more significant than that of[Formula: see text] (the angle between the vertical line of the portal and the hat). Monotonically decreasing responses were found in [Formula: see text] for [Formula: see text] and[Formula: see text]. The Pareto front of [Formula: see text] and[Formula: see text]was obtained. The ideal single-objective optimums for each response located at the ends of the Pareto front had values of 1.0560 for [Formula: see text] and 101.8 Pa for[Formula: see text].

The combined effect of lattice’s uniaxial strains and electron–phonon interaction’s screening on TBEC of the intersite bipolarons

2016 ◽  
Vol 30 (26) ◽  
pp. 1650186
Author(s):  
B. Yavidov ◽  
SH. Djumanov ◽  
T. Saparbaev ◽  
O. Ganiyev ◽  
S. Zholdassova ◽  
...  
Keyword(s):  
Ideal Gas ◽  
Einstein Condensation ◽  
Chain Model ◽  
One Dimensional ◽  
Electron Phonon Interaction ◽  
Model Lattice ◽  
Experimental Values ◽  
Bose Einstein ◽  
Derivatives Of ◽  
The Ideal

Having accepted a more generalized form for density-displacement type electron–phonon interaction (EPI) force we studied the simultaneous effect of uniaxial strains and EPI’s screening on the temperature of Bose–Einstein condensation [Formula: see text] of the ideal gas of intersite bipolarons. [Formula: see text] of the ideal gas of intersite bipolarons is calculated as a function of both strain and screening radius for a one-dimensional chain model of cuprates within the framework of Extended Holstein–Hubbard model. It is shown that the chain model lattice comprises the essential features of cuprates regarding of strain and screening effects on transition temperature [Formula: see text] of superconductivity. The obtained values of strain derivatives of [Formula: see text] [Formula: see text] are in qualitative agreement with the experimental values of [Formula: see text] [Formula: see text] of La[Formula: see text]Sr[Formula: see text]CuO4 under moderate screening regimes.

scholarly journals From three-dimensional weavings to swollen corneocytes

2011 ◽  
Vol 8 (62) ◽  
pp. 1274-1280 ◽  
Author(s):  
Myfanwy E. Evans ◽  
Stephen T. Hyde
Keyword(s):  
Three Dimensional ◽  
Simple Shape ◽  
Outermost Layer ◽  
One Dimensional ◽  
Periodic Arrays ◽  
Novel Technique ◽  
Structural Rigidity ◽  
Mammalian Skin ◽  
Shape Changes ◽  
The Ideal

A novel technique to generate three-dimensional Euclidean weavings, composed of close-packed, periodic arrays of one-dimensional fibres, is described. Some of these weavings are shown to dilate by simple shape changes of the constituent fibres (such as fibre straightening). The free volume within a chiral cubic example of a dilatant weaving, the ideal conformation of the G 129 weaving related to the Σ + rod packing, expands more than fivefold on filament straightening. This remarkable three-dimensional weaving, therefore, allows an unprecedented variation of packing density without loss of structural rigidity and is an attractive design target for materials. We propose that the G 129 weaving (ideal Σ + weaving) is formed by keratin fibres in the outermost layer of mammalian skin, probably templated by a folded membrane.

A Study of a Sharp 90 Degree Curved Flow

1992 ◽  
Author(s):  
R. H. Kim
Keyword(s):  
Turbulence Model ◽  
Ideal Gas ◽  
Radius Of Curvature ◽  
Dimensional Theory ◽  
One Dimensional ◽  
Algebraic Stress Model ◽  
Finite Difference Technique ◽  
Curved Tube ◽  
Kinetic Energy Loss ◽  
The Ideal

Abstract An investigation of air flow along a 90 degree elbow-like tube is conducted to determine the velocity and temperature distributions of the flow. The tube has a sharp 90 degree turn with a radius of curvature of almost zero. The flow is assumed to be a steady two-dimensional turbulent flow satisfying the ideal gas relation. The flow will be analyzed using a finite difference technique with the K-ε turbulence model, and the algebraic stress model (ASM). The FLUENT code was used to determine the parameter distributions in the passage. There are certain conditions for which the K-ε model does not describe the fluid phenomenon properly. For these conditions, an alternative turbulence model, the ASM with or without QUICK was employed. FLUENT has these models among its features. The results are compared with the result computed by using elementary one-dimensional theory including the kinetic energy loss along the passage of the sharp 90 degree curved tube.

Practical Passive Assembly: Gripper Design and Assembly Sequence Optimization

1999 ◽  
Author(s):  
Jayavardhan N. Marehalli ◽  
Robert H. Sturges
Keyword(s):  
Degrees Of Freedom ◽  
Optimization Problem ◽  
Automatic Assembly ◽  
Assembly Sequence ◽  
Feedback Systems ◽  
Preferred Direction ◽  
Ideal Orientation ◽  
Index Of Difficulty ◽  
Optimal Assembly ◽  
The Ideal

Abstract For efficient assembly without feedback systems (or, passive assembly), the assembler should know the ideal orientation of each component and the assembly sequence. A heuristic presented here finds an optimal assembly sequence and prescribes the orientation of the components for a minimum set of grippers — ideally one. The heuristic utilizes an index of difficulty (ID) that quantifies assembly. The ID for each task in the assembly process is computed based on a number of geometrical and operational properties. The objective of the optimization problem here is to minimize the assembly ID and categorize parts/subassemblies based on their preferred direction of assembly while allowing re-orientation of the base part. It is assumed that the preferred direction of assembly is vertically downwards consistent with manual as well as most automatic assembly protocols. Our attempt is to minimize the number of degrees of freedom required in a re-orienting fixture and mathematically derive the requirements for such a fixture. The assembly of a small engine is used as an example in this study due to the variety of ideally rigid parts involved.

Uncertainty, Profit, and the Limits of Markets

2021 ◽  
pp. 106591292110358
Author(s):  
Roni Hirsch
Keyword(s):  
Allocative Efficiency ◽  
Market Model ◽  
Perfect Competition ◽  
Political Debate ◽  
Trade Off ◽  
Starting Point ◽  
Knowledge Uncertainty ◽  
Market Benefits ◽  
Capitalist Democracies ◽  
The Ideal

The neoclassical market model is the overwhelming basis for contemporary views of markets as fair, efficient, or both. But is it an appropriate starting point? The article draws on Frank Knight’s 1920s work on the economics of uncertainty to show that the ideal of perfect competition conceals a tacit trade-off between equality and certainty. Largely undetected, this trade-off continues to govern financialized capitalist democracies, evading normative and political debate. By explaining how markets and firms resolve the problem of uncertainty, Knight shows that all supposed market benefits, even allocative efficiency, are not costless to society. More specifically, Knight argued that modern markets are premised on a tacit agreement between a handful of “daring” entrepreneurs and the “risk-averse” public: the former agree to carry the uncertainties of business-life in return for a substantially larger share of its power and rewards. Despite the highly static assumptions of neoclassicism, therefore, and its linked assumption of perfect knowledge, uncertainty is far from absent in modern economics. It is built into firms and markets and manifests itself as a steep social and material hierarchy.

One-Dimensional Optimization Problem

2020 ◽  
pp. 1-14
Author(s):  
Nita H. Shah ◽  
Poonam Prakash Mishra
Keyword(s):  
Optimization Problem ◽  
One Dimensional ◽  
Dimensional Optimization
Sign in / Sign up

Export Citation Format

Share Document