Nature Of Acceleration Research Articles

Development of modern directions of estimatology in the economic security of the enterprise

The object of research is the process of developing directions in estimatology of the economic security of an enterprise. Multiple objects are taken into account in the estimatology of economic security. It is revealed that the presence of many approaches to determining liminal (recommended, desired) values when assessing indicators of economic security is due to their multitasking. It is substantiated that the detected multitasking generates multilevel and multi-persistence of economic security. The property of variability of the degree of rigidity of the liminal (recommended and other) values of indicators is shown. The essence of the triple nature of acceleration (deceleration) of an enterprise is revealed. The use of critical time in the algorithm for assessing the state of economic security is proposed. An ambivalent approach to management decisions and activities of an enterprise in terms of their impact on economic security is determined. The features of taking into account the impact of the security of the company's stakeholders on its economic security are formulated. It is substantiated that the most influential liminal value of the personnel safety indicator is the salary in the replacement country, adjusted for the amount of rental payments and the difference between food costs in the replacement country and Ukraine. It is determined that overpaid dividends, and not their lack, have a greater impact on the safety of the enterprise. Differences in assessing the level and state of economic security (the level and state of its formation and provision) in the current and medium-term periods are systematized. It is substantiated that the key difference between the current and mid-term assessment is the use of technical indicators in the latter. It is proposed in assessing the level of security, which is based on the amount of shortage of profit before tax, to use the appropriate models for converting technical indicators into economic ones. The expediency of the symbiosis of functional and process approaches in assessing economic security is shown. The result of this research is the developed new directions in the estimatology of the economic security of the enterprise. The application of the developed directions allows a more comprehensive and systematic assessment of various objects of economic security, both in the current and in the medium term.

FLUCTUATIONS OF THE CARGO TRANSPORTED BY LIFTING CRANE: SIMULATION AND ANALYSIS

Introduction.Reducing fluctuations in the load transported by hoisting cranes with a flexible rope suspension of the load is an urgent task since it can significantly reduce the time taken to complete the operation of moving the load. A promising direction for reducing load fluctuations is to optimize the trajectory of movement of the load suspension upper point.Materials and methods.The paper discussed the method of mathematical simulation of plane vibrations of a load moved by a crane with a horizontally moving suspension point, using the software of the MATLAB system. For modeling, the authors used the function of the MATLAB ode45 system, intended for the numerical solution of systems of non-stationary differential equations of arbitrary order.The second-orderdifferential equation used to describe the fluctuations of the transported load and its implementation in the form of program code was presented. Moreover, the authors demonstrated the elements of program code for the analysis and visualization of simulation results.Results.The authors obtained and presented the series of graphs in the inclination angle’s changing of the cargo rope, the acceleration of the suspension point and the value of the objective function with the sinusoidal nature of the acceleration. The objective function was the sum of the absolute values of the deflection angle of the rope and the first derivative at the final moment of the suspension point’s movement with acceleration.Discussion and conclusions.As a result, the paper shows that the system with energy dissipation does not reach the zero value of the objective function even by a symmetrical nature of acceleration and deceleration of the suspension point. Therefore, it is necessary to give asymmetry to the acceleration and deceleration periods of the suspension point in order to completely absorb the residual fluctuations of the load.

Accelerated Aging of Vulcanized Rubber. Factors Determining the Relation between Oven and Bomb Aging

Abstract A study has been made of the influence of the following factors on the relative rates of tensile deterioration of natural rubber vulcanizates in the Geer oven and oxygen bomb, both at 70° C : period of vulcanization, sulfur ratio, nature of accelerator. Expressing this relation as the oven/bomb ratio, i.e., the ratio between oven and bomb aging periods that give the same deterioration, the following conclusions are drawn. (1) Varying the period of vulcanization of a given mix over a moderate range (2:3) around the optimum does not noticeably alter the oven/bomb ratio, except in unaccelerated mixes, where overvulcanization gave an abnormally low ratio, owing to the rubber perishing very rapidly in the oven. (2) The effect of varying the sulfur ratio within the usual limits for soft rubbers is small, and appears to result from the quicker vulcanization of the mixes richer in sulfur. (3) The nature of the accelerator profoundly affects the ratio, values ranging from 3 to 27 being found among the present mixes ; this effect is believed to be exerted through the influence of the accelerator both on rate of vulcanization and on the oxidizability of the vulcanizate. Theoretical considerations indicate that a rubber which vulcanizes quickly and (or) oxidizes slowly should give a low oven/bomb ratio, whereas one that vulcanizes slowly and(or) oxidizes quickly should give a higher ratio. The experimental data are generally in accord with this, and there is evidence that both rate of vulcanization and oxidizability can have an important effect, but the data do not enable the separate effect of each to be assessed exactly. The bearing of the results on the use of the oven and bomb tests is briefly discussed. It is shown that they demonstrate the fallacy of using a single factor for converting oven to bomb aging periods or vice versa, and that the relative natural aging resistances of widely different vulcanizates cannot be reliably assessed by either test, a limitation arising from the fact that the relative importance of oxidative decay and aftervulcanization varies from one type of mix to another, and that the temperature coefficients of these processes are not necessarily the same. These facts are very important in relation to the choice and application of accelerated aging tests for specification purposes, since these usually have to be applied to rubbers of unknown compositions, which are likely to vary widely in their relative response to different aging conditions.