Rational Design Solution Based on Mathematical Modeling of an Interference Fit

The proposed scientific work considers and substantiates an effective method for selecting interference fit on smooth cylindrical surfaces of parts, which can be successfully applied in automated design of fit. Based on the analysis of numerical and analytical research of the results of calculation and design of the considered joints, a flat image of a mathematical model of the area of existence of geometric parameter values in a two-dimensional coordinate system (diameter and working length of the fit) was first obtained. At the next stage of modeling many alternative i-th standard interference fits were built. Within each i-th object centers of grouping rational values of geometric parameters were defined. They are formed by crossing the largest segments of allowable ranges of changing values of diameter and working length in each of the models of sets. The position of such centers is analytically described using the mathematical apparatus of the theory of R-functions. On the considered specific example of this research, the criterion for choosing a rational standard interference fit is formulated depending on the values of geometric parameters. The meaning of this criterion is that within the flat geometric image of the model, the shortest distance is analytically determined - the segment between the points of the grouping centers of the model of set of the �-th fit and the model of the area of existence of values. The effectiveness and advisability of the formulated criterion is illustrated by comparison with other criterions obtained in previous researches of the authors. As a result of the research, it was revealed that the task of choosing a single rational design solution is significantly simplified if several criterions of one of the alternative fits coincide.

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Method of Design of Interference Fit Based on Complex Mathematical Modeling

Advances in Design, Simulation and Manufacturing III - Lecture Notes in Mechanical Engineering ◽

10.1007/978-3-030-50794-7_5 ◽

2020 ◽

pp. 45-54

Author(s):

Vladimir Nechiporenko ◽

Valentin Salo ◽

Petro Litovchenko ◽

Vladislav Yemanov ◽

Stanislav Horielyshev

Keyword(s):

Mathematical Modeling ◽

Interference Fit ◽

Method Of Design

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Constructing synthetic-protein assemblies from de novo designed 310 helices

10.1101/2021.12.11.471898 ◽

2021 ◽

Author(s):

Prasun Kumar ◽

Neil G. Paterson ◽

Jonathan Clayden ◽

Derek N. Woolfson

Keyword(s):

Rational Design ◽

De Novo ◽

Protein Structures ◽

Water Soluble ◽

Design Solution ◽

Protein Assemblies ◽

Synthetic Protein ◽

Hydrophobic Cores ◽

Α Helix ◽

Helical Folding

Compared with the iconic α helix, 310 helices occur much less frequently in protein structures. The different 310-helical parameters lead to energetically less favourable internal energies, and a reduced tendency to pack into defined higher-order structures. Consequently, in natural proteins, 310 helices rarely extend past 6 residues, and do not form regular supersecondary, tertiary, or quaternary interactions. Here, we show that despite their absence in nature, synthetic protein-like assemblies can be built from 310 helices. We report the rational design, solution-phase characterisation, and an X-ray crystal structure for water-soluble bundles of 310 helices with consolidated hydrophobic cores. The design uses 6-residue repeats informed by analysing natural 310 helices, and incorporates aminoisobutyric acid residues. Design iterations reveal a tipping point between α-helical and 310-helical folding, and identify features required for stabilising assemblies in this unexplored region of protein-structure space.

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Performance based approach in design of freeform space structures

Facta universitatis - series Architecture and Civil Engineering ◽

10.2298/fuace160404011n ◽

2017 ◽

Vol 15 (2) ◽

pp. 153-166

Author(s):

Miodrag Nestorovic ◽

Predrag Nestorovic ◽

Jelena Milosevic

Keyword(s):

Design Process ◽

Rational Design ◽

Optical Measurement ◽

Digital Fabrication ◽

Digital Design ◽

Physical Models ◽

Design Solution ◽

Roof Structure ◽

Cad Cam ◽

Context Specific

This paper is related to the fact that use of computational tools for form generation, analysis and digital fabrication (CAD/CAM/CAE) in an efficient way enables accurate representation of ideas, simulation of diverse impact and production of rational design solutions. Application of geometrical and numerical computational methods and adoption of performance based priorities enables formal exploration in constrained conditions and improvement of architectural engineering design process. Implementation of advanced technologies in 3D digital design process facilitates production of unconventional complex designs, their verification by construction of physical models and experimental diagnostics, as phase preceding construction of real structure. Within this work concept that provides design of non-standard, context-specific, freeform structure using rapid prototyping technology and 3D optical measurement will be reviewed. The analyzed design solution of roof structure above atrium of National Museum in Belgrade has a function to demonstrate the effectiveness of this approach.

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Conveyor-Belt Dryers with Tangential Flow for Food Drying: Mathematical Modeling and Design Guidelines for Final Moisture Content Higher Than the Critical Value

Inventions ◽

10.3390/inventions5020022 ◽

2020 ◽

Vol 5 (2) ◽

pp. 22

Author(s):

Dario Friso

Keyword(s):

Mathematical Modeling ◽

Moisture Content ◽

Rational Design ◽

Conveyor Belt ◽

Design Guidelines ◽

Final Moisture Content ◽

Temperature Sensitive ◽

Optimized Design ◽

Tangential Flow ◽

Product Flow

The mathematical modeling presented in this work concerns the conveyor-belt dryer with the tangential flow of air with respect to food. This dryer, if operating in co-current, has the advantage of well preserving the organoleptic and nutritional qualities of the dried product. In fact, it has a low air temperature in the final stretch where the product has low moisture content and is therefore more temperature sensitive. It is a bulkier dryer than the continuous through-circulation conveyor dryer with a perforated belt. The latter is therefore more frequently used and has received greater study attention from researchers and designers of the industry. With the aim to propose guidelines for a rational design of the conveyor-belt dryer with tangential flow, a mathematical model was developed here through the differentiation of the drying rate equation followed by its integration performed along the dryer belt. Consequently, and with the assumption that the final moisture content XF of the product is higher than the critical moisture content XC, the relationships between the intensive quantities (temperatures, humidity and enthalpies), the extensive quantities (air and product flow rates) and the dimensional ones (length and width of the belt), were obtained. Finally, on the basis of these relationships, the rules for an optimized design for XF > XC were obtained and experimentally evaluated.

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Design Approaches for Safety Increasing and Risk Decreasing for the Civil Aircraft’s Operation

Safety and Risk Assessment of Civil Aircraft during Operation ◽

10.5772/intechopen.92560 ◽

2020 ◽

Author(s):

Dmytro Tiniakov

Keyword(s):

Rational Design ◽

Critical Incidents ◽

Structural Features ◽

Structure Design ◽

Design Solution ◽

Commercial Aircraft ◽

Common Features ◽

Civil Aircraft ◽

Design Solutions ◽

Structural Solutions

The safety and risks of civil aircraft operation depend on a lot of factors. One of them is the structural features of an aircraft. In aviation history, there are examples when “non-rational” design solution was the reason for crashes, but there are examples about successful civil aircraft that have “rational” structure and long operational time without critical incidents. So, how can a designer provide high safety of level and decrease incidents’ risks in time of a regular aircraft operation? This chapter partly can help to understand some reasons and approaches for providing “rational” aircraft structure. Design solutions can be divided into some groups by some common features and requirements. They are maintainability, serviceability, accessibility, labor effort decreasing, weather requirements, transportation, etc. All these groups depend on engineers’ structural solutions. They are interdependent and often contradictory. In other words, if one of the features will be better, another will be worse at the same time. And, a designer must remember all the time about this and try to find compromise between different requirements. The successful commercial aircraft is composed of a set of rational design solutions for these specific tasks.

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EXPERIMENTAL STUDY ON BEARING RESISTANCE OF SHORT DISPLACEMENT PILE GROUPS IN DENSE SANDS

Journal of Civil Engineering and Management ◽

10.3846/jcem.2019.10403 ◽

2019 ◽

Vol 25 (6) ◽

pp. 551-558

Author(s):

Arnoldas Norkus ◽

Vaidas Martinkus

Keyword(s):

Experimental Study ◽

Soil Structure ◽

Rational Design ◽

Pile Group ◽

Soil Structure Interaction ◽

Design Solution ◽

Additional Stress ◽

Pile Groups ◽

Limit States ◽

Structure Interaction

The prediction of the behavior of structures interacting with soil is one of the main challenges in structural design. Accurate evaluation of soil–structure interaction ensures a rational design solution for the superstructure and foundation of a building. In structural analysis, one of the key problems is the identification of relevant movements of the foundation considering the interaction between the superstructure, foundation and ground (the soil mass around the foundation). The correct assessment of soil–structure interaction contributes to the rational constructional design of the superstructure and foundation and allows avoiding violations of requirements for ultimate and serviceability limit states possible due to unpredicted additional stress on the structural system. Resistance predictions for pile group foundations is a complex problem, which may be the reason for scattered and insufficient information available despite numerous experimental and numerical studies, predominated by the focus on partial empirical relationships. This experimental study analyzed the prototype of a short displacement pile group with a flexible pile cap in terms of the bearing capacity and deformation behavior while subjected to static axial vertical load. In particular, attention was given to the resistance–stiffness evolution of single piles acting in a pile group with different spacing. Test results of short displacement pile groups were used to verify known models for the bearing resistance prediction of the pile group.

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Mathematical Modelling of Conveyor-Belt Dryers with Tangential Flow for Food Drying up to Final Moisture Content below the Critical Value

Inventions ◽

10.3390/inventions6020043 ◽

2021 ◽

Vol 6 (2) ◽

pp. 43

Author(s):

Dario Friso

Keyword(s):

Mathematical Modeling ◽

Moisture Content ◽

Flow Rate ◽

Rational Design ◽

Cross Flow ◽

Conveyor Belt ◽

Final Moisture Content ◽

Optimized Design ◽

Tangential Flow ◽

Product Flow

This work presents the mathematical modeling of the conveyor-belt dryer with tangential flow operating in co-current, which has the advantage of improving the preservation of the organoleptic and nutritional qualities of the dried food. On the one hand, it is a more cumbersome dryer than the perforated cross flow belt dryer but, on the other hand, it has a low air temperature in the final section where the product has a low moisture content and, therefore, it is more heat sensitive. The results of the mathematical modeling allowed a series of guidelines to be developed for a rational design of the conveyor-belt dryer with tangential flow for the specific case of the moisture content of the final product XF lower than the critical one XC (XF < XC). In fact, this work follows a precedent in which a mathematical model was developed through the differentiation of the drying rate equation along the dryer belt with the hypothesis that the final moisture content XF of the product was higher than the critical one XC. The relationships between the extensive quantities (air flow rate and product flow rate), the intensive quantities (temperatures, moisture content and enthalpies) and the dimensional ones (length and width of the belt) were then obtained. Finally, based on these relationships, the rules for an optimized design for XF < XC were obtained.

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Shaping the appearance of a long-range aircraft at the stage of developing a technical proposal

Herald of Dagestan State Technical University Technical Sciences ◽

10.21822/2073-6185-2020-47-3-49-59 ◽

2020 ◽

Vol 47 (3) ◽

pp. 49-59

Author(s):

A. A. Gorbunov ◽

A. D. Pripadchev

Keyword(s):

Long Range ◽

Rational Design ◽

Performance Criteria ◽

Design Stage ◽

Design Solution ◽

Design Parameters ◽

Preliminary Design ◽

Efficiency Criterion ◽

Rational Design Parameters ◽

Preliminary Design Stage

Objective. The process of designing a long-range aircraft, in particular at the preliminary design stage, involves comparing and analyzing a large number of design alternatives with specified performance criteria. At the same time, the problem of choosing the composition of rational design parameters is solved, which is an actual problem of the preliminary design stage of a long-range aircraft. Methods. The developed method allows determining the vector of parameters that provides rational characteristics for a given efficiency criterion. In this regard, the authors propose to introduce a global efficiency criterion - the takeoff weight of the long-range aircraft, and the specific criteria are the aerodynamic quality in cruise and the value of fuel efficiency. Results. In this formulation of the design problem, it is necessary to solve several interrelated problems, some of which are formalized, while others do not yet have a mathematical construct and software that allows automating the process. A distinctive feature of the proposed approach to finding a rational design solution is the use of statistical analysis methods in combination with methods of high-precision mathematical modeling, software-implemented in a single information environment using the Fortran V and C++ languages. Conclusion. The proposed method for selecting the composition of rational design parameters allows forming the appearance and providing the specified characteristics for its component elements at the early stages and stages of designing the long-range aircraft.

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