Research of the characteristics of flat grinding wheels for high-speed machining based on numerical modeling

Flat grinding wheels of two types with different diameters were studied by numerical modeling in order to establish a rational standard size of the tool for high-speed processing. Critical rotation speeds of grinding wheels are determined. The fields of maximum stresses and plastic deformations are obtained. Taking into account the required processing accuracy, the optimal speed modes are determined. Keywords: grinding wheel, modeling, high-speed machining, stresses, plastic deformation, machining accuracy. [email protected]

EFFECTIVE METHOD OF SELECTING INTERFERENCE FIT BASED ON AUTOMATED COMPUTER MODEL CONSTRUCTION

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.

To substantiate the standard range of planning and technological solutions of farms for milk production

Annotation Purpose. Improving the efficiency of milk production by determining the rational standard size range of design technological solutions for the premises of farms for the content of dairy livestock. Methods. Theoretical provisions for the calculation of design and technological solutions for the construction of livestock buildings, we use graphical and graphoanalytical methods. Results. The design and technological schemes were considered of cowsheds with different placement of the number technological rows and grouping of stalls, for: a two-row scheme with a central aft passage; six-row layout of stalls (with a feed table along the outer perimeter and with a feed table in the center of the barn); 8-row layout of stalls in the barn with two feed tables.The cost of building a room of sandwich panels for a size range of 128 cows per cow is 20601 UAH against 25294 UAHconstructions of brick, which is 22% less than the cost while we have an increase in air volume per cow, respectively, 77 m3 vs. 55 m3 Conclusions 1. The rational standard size range of the milk production farm was determined: premises for 128 cows have 4 rows of 2 stall groups of 16 cows each; premises for 256 cows has 4 rows with 4 stall groups of 16 cows or 8 rows with 2 stall groups of 16 cows; premises for 384 cows has 8 rows with 3 stall groups of 16 cows each or 8 rows with 4 stall groups of 12 cows each; keeping 512 cows the premises has 8 rows of 4 stall groups of 16 cows. In accordance with technical and economic indicators, the most effective content is 386 (400) cows. 2. The economic effect is ensured by rational distribution of the size range of the stalls, their number, and the aisle size in accordance with the zoo-technical requirements for maintaining a highly productive livestock of cows for milk production farms and is 8–16% of the cost of construction and its subsequent maintenance, as a result, the area of the premises decreases for keeping cows and, accordingly, the amount of building materials. Keywords: stall, feed table, barn, stall section, feeding front, type-size range.

Research on the Knowledge Character and Classification of Intangible Cultural Heritage

As the knowledge of intangible cultural heritage is the experience which is accumulated for a long time, it is difficult to express the complex relationships completely. In order to preserve the content of intangible cultural heritage effectively, the knowledge should be classified by a rational standard. Firstly, this paper discussed the special character and information processing technology of intangible culture heritage; Secondly, the classification of intangible cultural heritage is designed based on its character and the theory of knowledge classification, and then a knowledge modeling framework for intangible cultural heritage is designed based on this classification. Application has proved that it is feasible and effective, and could help the users to master the knowledge and its relationship from various perspectives.

Manufacturing Social Responsibility Benchmarks in the Competitive Intelligence Age

The themes explored elsewhere in this volume, on the intersection between information technology and social responsibility, take on new shapes when considered in the context of competitive intelligence. Using the (probably) apocryphal Thomson-Raytheon story as a launching point, this chapter will explore the emergence of social responsibility benchmarks in the competitive intelligence age. This analysis is heavily flavored by my own experiences trying to understand the French approach to competitive intelligence. The paper reviews attempts by competitive intelligence agents in the US and France to manufacture Social Responsibility benchmarks in the contexts of covert operations, competitive strategy, corporate intelligence, economic security, economic intelligence, and economic warfare. The conclusion of the paper will argue that the construction of social responsibility is a local-level human accomplishment, not a global-level rational standard. Furthermore, the paper implies that the burden of social responsibility lies more heavily on the successful economic oppressor than the unsuccessful economic resistance.

Manufacturing Social Responsibility Benchmarks in the Competitive Intelligence Age

The themes explored elsewhere in this volume, on the intersection between information technology and social responsibility, take on new shapes when considered in the context of competitive intelligence. Using the (probably) apocryphal Thomson-Raytheon story as a launching point, this chapter will explore the emergence of social responsibility benchmarks in the competitive intelligence age. This analysis is heavily flavored by my own experiences trying to understand the French approach to competitive intelligence. The paper reviews attempts by competitive intelligence agents in the US and France to manufacture Social Responsibility benchmarks in the contexts of covert operations, competitive strategy, corporate intelligence, economic security, economic intelligence, and economic warfare. The conclusion of the paper will argue that the construction of social responsibility is a local-level human accomplishment, not a global-level rational standard. Furthermore, the paper implies that the burden of social responsibility lies more heavily on the successful economic oppressor than the unsuccessful economic resistance.

Assessing Knowledge Structures: Don't Always Call an Expert

Measures of knowledge structures can be used to access and evaluate conceptual understanding for assessment and training purposes. Typically, the quality of an individual's knowledge structure is determined by comparing it to a standard knowledge structure that is an aggregate of the structures of several experts. Recent research suggests that this approach may not be appropriate for all domains. This study investigated different approaches for forming a standard knowledge structure for two knowledge structure measures: relatedness ratings and a diagramming task. Three approaches to developing knowledge standards were compared: a standard derived from expert data, a standard based on high-performing students, and a rational standard developed through an analysis of instructional materials. The knowledge standards were compared in their ability to predict performance on a multiple-choice test. The results showed that comparison of students' structures with a standard constructed by aggregating high-performing student structures produced scores that were independently predictive of performance for both measures, whereas the expert standard resulted in independently predictive knowledge scores for only the diagramming task. For both measures, the high-performer standard and the aggregate expert standard were superior to the rational standard. These results offer support for using standards other than the expert-consensus standard typically used when assessing the quality of knowledge structures.

Testing of zero-slump piling concrete

For several years it had been noted in the field that in the absence of an accepted, rational standard method for testing impact-placed zero-slump piling concrete, a variety of strength levels were produced from the same sample of fresh concrete depending upon which of a variety of test methods happened to be used. Finally, in 1977 the Canadian Standards Association published a standard method. This method subsequently proved ambiguous and impractical in practice to many field engineers.This paper presents the results of a laboratory and field study conducted during 1985 directed at the rational development of a practical test method to realistically predict the appropriate concrete strength, [Formula: see text], to be used in the calculation of the structural load-carrying capacity of this type of pile. Key words: zero slump, impact piles, energy input, vibration, compaction, concrete strength.