ONE OF THE POSSIBLE APPROACHES FOR DESIGNING A HOB CUTTER FOR MACHINING A SMALL CYCLOIDAL CONE

Author(s):  
В.В. Куц ◽  
А.А. Панин ◽  
Д.Н. Тютюнов ◽  
К.В. Жилина

Предлагается краткий обзор промышленного производства червячных фрез. Показано, что повышение качества и производительности изготовления зубчатых колес является необходимым условием снижения себестоимости и расширения объемов производства зубчатых колес на отечественных предприятиях. Главным требованием, предъявляемым к зубьям данной фрезы, является то, чтобы в результате заточки по передней поверхности, которая лежит в осевой плоскости фрезы, профиль зубьев сохранялся до почти полного их износа. Поэтому особое внимание уделяется выбору кривой затылования с учётом целого ряда факторов, способствующих совершенствованию процесса обработки. Отмечено, что затылование имеет ряд преимуществ, в сравнении с острой заточкой фрез. Изложен новый подход к проектированию рабочей оснастки для обработки малых колес циклоидной передачи и исследованы теоретически допустимые интервалы изменения задних углов при затыловании. Установлено, что несмотря на преимущества циклоидальной фрезы перед другими типами затылованных фрез в скорости и точности обработки, она имеет один недостаток - довольно малый промежуток применимости на дуге циклоиды. На основе существующих подходов разработан вариант затылования зубьев червячной фрезы по циклоиде The article provides an overview of the industrial production of hob cutters. We show that improving the quality and productivity of gear wheel manufacturing is a necessary condition for reducing the cost and expanding the production of gear wheels at domestic enterprises. The main requirement for the teeth of this cutter is that, as a result of sharpening on the front surface, which lies in the axial plane of the cutter, the profile of the teeth remains sharp until they are almost completely worn out. Therefore, we paid special attention to the choice of the relief curve, taking into account a number of factors that contribute to the improvement of the processing process. We note that relief has a number of advantages in comparison with sharpening of cutters. We give a new approach to the design of working equipment for processing small cycloidal wheels and investigate the theoretically permissible intervals of variation of the rear angles during relief. We established that despite the advantages of a cycloidal cutter over other types of undercut cutters in terms of speed and machining accuracy, it has one drawback - a rather small range of applicability on the cycloid arc. On the basis of existing approaches, we developed a variant of the relief of the teeth of the worm cutter along the cycloid

1970 ◽  
Vol 10 (1) ◽  
pp. 19
Author(s):  
A. J. Willis

Up to the present there has been insufficient experience in marketing natural gas in Australia to give precise opinions based upon experience. This paper therefore deals mainly with the problems to be encountered and expected methods of dealing with them.Since natural gas was first discovered, frequent comparisons have been drawn with the American industry's position and it is often suggested that this should form the pattern for Australian development. I would question whether the parallel exists to any great degree as the American industry was established and gained a firm foundation from cheap surplus supply of natural gas.Australia has begun marketing natural gas under much more difficult circumstances. It is being given no opportunity of cheap raw material to build up a load and must fight for much of its business on very narrow cost margin differentials. The American gas distributing industry was able to quickly write off conversion costs and rehabilitate its operation, placing it in a strong position for future marketing activities.Gas Purchase contracts already negotiated are a compromise of conflicting interests. Producers desire maximum well head prices, pipeliners satisfactory margins and distributors an adequate return on investment. Large volume sales are necessary for economic operation but frequently are only obtainable at rates very close to city gate prices.Large special type users, such as power houses or fertilizer plants, can provide base business but due to their special nature, are not considered in detail.Industry generally, is where the major volume sales will be obtained. The first requirement is the construction of tariffs to attract this business but which will not conflict either with existing revenue or with the various types of customers. A new approach to tariffs and special contracts is required by the distributor to meet the flexible nature of competition from the oil industry.The gas marketer must maximize the advantages of natural gas as a fuel. It is not necessary merely to have gas available at attractive prices. Australian industry is extremely conservative and potential users may need education on the true importance of fuel in their operation. Many look at the cost of the fuel only, without realising the other advantages which can be gained from the introduction of this more refined material. Even after supply has commenced, it has been found necessary to spend considerable time with customers to show how the new fuel may be used to the greatest advantage and economy.The third market area lies in domestic and commercial business. The existing traditional market of cooking and water and space heating will remain the basic load and the main requirement is to convince householders of the real value of natural gas. Domestic business is strongly influenced by personal choice and prestige value while sometimes ignoring cost and utility. Other marginal domestic markets will develop, but whilst valuable, are unlikely to provide a significant load.Commercial sales are a market for which natural gas should obtain a very high level of saturation. Its advantages in utilisation and cost are far ahead of any competitive fuel. This market however will need to be sold in a positive way.After the first market developments have taken place, it is expected that gas distributors will consider extending gas purchase contracts. Negotiations should take place under much more realistic conditions, as experience will exist to determine what is a fair basis of purchase to allow further market development to take place.


Author(s):  
James F. Mancuso

IBM PC compatible computers are widely used in microscopy for applications ranging from control to image acquisition and analysis. The choice of IBM-PC based systems over competing computer platforms can be based on technical merit alone or on a number of factors relating to economics, availability of peripherals, management dictum, or simple personal preference.IBM-PC got a strong “head start” by first dominating clerical, document processing and financial applications. The use of these computers spilled into the laboratory where the DOS based IBM-PC replaced mini-computers. Compared to minicomputer, the PC provided a more for cost-effective platform for applications in numerical analysis, engineering and design, instrument control, image acquisition and image processing. In addition, the sitewide use of a common PC platform could reduce the cost of training and support services relative to cases where many different computer platforms were used. This could be especially true for the microscopists who must use computers in both the laboratory and the office.


2019 ◽  
Vol 2019 (4) ◽  
pp. 7-22
Author(s):  
Georges Bridel ◽  
Zdobyslaw Goraj ◽  
Lukasz Kiszkowiak ◽  
Jean-Georges Brévot ◽  
Jean-Pierre Devaux ◽  
...  

Abstract Advanced jet training still relies on old concepts and solutions that are no longer efficient when considering the current and forthcoming changes in air combat. The cost of those old solutions to develop and maintain combat pilot skills are important, adding even more constraints to the training limitations. The requirement of having a trainer aircraft able to perform also light combat aircraft operational mission is adding unnecessary complexity and cost without any real operational advantages to air combat mission training. Thanks to emerging technologies, the JANUS project will study the feasibility of a brand-new concept of agile manoeuvrable training aircraft and an integrated training system, able to provide a live, virtual and constructive environment. The JANUS concept is based on a lightweight, low-cost, high energy aircraft associated to a ground based Integrated Training System providing simulated and emulated signals, simulated and real opponents, combined with real-time feedback on pilot’s physiological characteristics: traditionally embedded sensors are replaced with emulated signals, simulated opponents are proposed to the pilot, enabling out of sight engagement. JANUS is also providing new cost effective and more realistic solutions for “Red air aircraft” missions, organised in so-called “Aggressor Squadrons”.


Author(s):  
Anastasiya V. Mironova ◽  
Igor’ V. Liskin ◽  
Irina I. Afonina

Neglect of soils leads to their degradation, worsens useful properties, and reduces fertility and productivity. (Research purpose) The research purpose is in conducting a comparative analysis of technologies for treating degraded soils, taking into account the economic feasibility of their restoration in non-black-soil regions of Russia. (Materials and methods) The article shows the main technological scheme of restoration of degraded soils. Authors have identified the main groups of land that are located in non-black-soil regions of Russia. (Results and discussion) The article presents the need for equipment, economic and labor costs for the restoration of each type of land in the non-black-soil regions of Russia. Authors took into account that the salary of machine operators depends on the time of direct execution of the task. It was found that the restoration of virgin and fallow lands was the most preferable from the economic, energy-saving and environmental points of view. The article shows that the restoration of pasture areas exceeds the cost of processing virgin lands, but the number of necessary machine and tractor units is comparable to work on virgin lands. Authors recommend to develop the soils with woody and shrubby vegetation in the first place, starting with land occupied by young plants. It is necessary to take into account the criteria for the fertility of the soil layer. It was found that soils with a small excess of moisture have small cost of its development, while on heavily swampy soils the cost of work on their development is many times higher than the cost of restoring other types of land. (Conclusion) The article shows that the restoration of neglected land is a necessary condition for improving the provision of human needs for food and a number of industrial goods. First of all, it is necessary to develop land that requires minimal investment of economic and labor costs.


2004 ◽  
Vol 61 (7) ◽  
pp. 1269-1284 ◽  
Author(s):  
RIC Chris Francis ◽  
Steven E Campana

In 1985, Boehlert (Fish. Bull. 83: 103–117) suggested that fish age could be estimated from otolith measurements. Since that time, a number of inferential techniques have been proposed and tested in a range of species. A review of these techniques shows that all are subject to at least one of four types of bias. In addition, they all focus on assigning ages to individual fish, whereas the estimation of population parameters (particularly proportions at age) is usually the goal. We propose a new flexible method of inference based on mixture analysis, which avoids these biases and makes better use of the data. We argue that the most appropriate technique for evaluating the performance of these methods is a cost–benefit analysis that compares the cost of the estimated ages with that of the traditional annulus count method. A simulation experiment is used to illustrate both the new method and the cost–benefit analysis.


2011 ◽  
Vol 09 (supp01) ◽  
pp. 415-422
Author(s):  
D. SALGADO ◽  
J. L. SÁNCHEZ-GÓMEZ ◽  
M. FERRERO

We exploit the cone structure of unnormalized quantum states to reformulate the separability problem. Firstly a convex combination of every quantum state ρ in terms of a state Cρ with the same rank and another one Eρ with lower rank is perfomed, with weights 1 − λρ and λρ, respectively. Secondly a scalar [Formula: see text] is computed. Then ρ is separable if, and only if, [Formula: see text]. The computation of [Formula: see text] has been undergone under the simplest choice for Cρ as a product matrix and Eρ being a pure state, valid for any bipartite and multipartite system in arbitrary dimensions. A necessary condition is also formulated when Eρ is not pure in the bipartite case.


2021 ◽  
Vol 4 (4) ◽  
pp. 49-55
Author(s):  
Bunyod Nosirov ◽  

The article discusses the issues of the activity of the public catering system during the Soviet period, in particular, the policy and problems in this area affecting the issues of ensuring the material and technical base, as well as the need of the population itself in the field of public catering.During the years of Soviet rule, new directions in the public catering system were formed. A new approach was integrated in the management structure and in provision.A differentiated approach was introduced in the direction of public catering, i.e. reform in the issue of service, the cost of public catering. In other words, the cost price and service (in the public catering system) in large enterprises differed sharply from the prices in schools.


Author(s):  
A. Krasheninin

Modern vehicles operated on the railways of Ukraine have almost exhausted or exceeded their resource. The overuse of financial and material resources for their maintenance continues. The standard service life of vehicles was calculated on stable economic conditions of use of vehicles and their timely updating in process of aging. The service life of modern vehicles is determined by the influence of many factors, the disregard of which can lead to significant costs, even in compliance with the standard service life. For railway transport, these factors need modern clarification, as in operation their service life often exceeds the standard or, as for intermodal transport, the service life does not have a strict justification. Accordingly, the article analyzes the issues of assessing the impact on the service life of vehicles of the components of the cost of its maintenance and average daily mileage. It is shown that, firstly, the definition of the service life of vehicles must be linked to the cost of vehicle development, its creation, testing and production, the cost of operation and storage, as well as additional costs, and secondly , with the optimal average daily mileage, at which all the costs are minimal.


Author(s):  
Н. Р. Асадуллина

Formulation of the problem. The article reflects the assessment of the competitiveness of processed fruit and vegetable products, the qualitative characteristics of fruit and vegetable products are substantiated, as well as the parameters of the degree of consistency of expert opinions based on the calculation of the concordance coefficient. The purpose of the research is to reflect and characterize existing methods of integrated assessment of the competitiveness of processed fruit and vegetable products. The object of research – the process of determining the quality of products produced, as well as the competitiveness of processed fruit and vegetable products. The methods used in the research – logical, comparative, analytical, scientific and methodological. The hypothesis of the research is to assume the dependence of the competitiveness of processed fruit and vegetable products and its sales volumes. The statement of basic materials. The buyer prefers products depending on the purpose and use of this product. In the course of further processing, the buyer pays attention to the volume of packaging, the suitability of the packaging for the content of the product in it, the maximum time for the storage of products. The article suggests such indicators of quality of processed fruit and vegetable production: biochemical composition of products; packaging of products; design and design of products; appearance and consistency; terms of product suitability; cost of production per kilogram of production. The originality and practical significance of the research is that the author substantiates the degree of influence of the proposed indicators on competitiveness on the basis of expert assessments. The number of points is determined depending on the number of factors considered. The degree of consensus of expert opinions is established on the basis of calculating the coefficient of concordation. Conclusions of the research. In the process of packaging the product and its production must take into account the directions of its use. For further industrial consumption, processed fruit and vegetable products can be made with a higher content of dry soluble substances, vitamins, sugars, and acidity. This will save on the cost of packaging, transport costs, and handling operations.


2014 ◽  
Vol 35 (4) ◽  
pp. 83-95 ◽  
Author(s):  
Daniel Czaja ◽  
Tadeusz Chmielnak ◽  
Sebastian Lepszy

Abstract A thermodynamic and economic analysis of a GT10 gas turbine integrated with the air bottoming cycle is presented. The results are compared to commercially available combined cycle power plants based on the same gas turbine. The systems under analysis have a better chance of competing with steam bottoming cycle configurations in a small range of the power output capacity. The aim of the calculations is to determine the final cost of electricity generated by the gas turbine air bottoming cycle based on a 25 MW GT10 gas turbine with the exhaust gas mass flow rate of about 80 kg/s. The article shows the results of thermodynamic optimization of the selection of the technological structure of gas turbine air bottoming cycle and of a comparative economic analysis. Quantities are determined that have a decisive impact on the considered units profitability and competitiveness compared to the popular technology based on the steam bottoming cycle. The ultimate quantity that can be compared in the calculations is the cost of 1 MWh of electricity. It should be noted that the systems analyzed herein are power plants where electricity is the only generated product. The performed calculations do not take account of any other (potential) revenues from the sale of energy origin certificates. Keywords: Gas turbine air bottoming cycle, Air bottoming cycle, Gas turbine, GT10


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