scholarly journals Economical Optimization of the Mechanized Longwall Faces with Top Coal Caving Mining, In Horizontal Slices

2016 ◽  
Vol 61 (3) ◽  
pp. 651-676 ◽  
Author(s):  
Ilie Onica ◽  
Viorel Mihăilescu ◽  
Felicia Andrioni

Abstract To increase the economic and technical performances of the Jiu Valley hard coal mines, the top coal caving, in horizontal slices, mining methods (Bourbaki methods) were introduced, adapted to the local geo-mining conditions. This mining was successfully experimented by using classical technology, using the individual supports and coal blasting. In the future, it is planned to adopt the mechanized technology, with frame supports and shearers. The mechanized longwall faces with top coal caving mining, in horizontal slices, of coal seam no. 3 could be efficient only if the sizes of the top coal height and the panel length determine a minimum cost of production. Therefore, the goal of this paper is the optimization of these parameters, from a technical and economic point of view, taking into account the general model of the cost function, at the panel level. For that, it was necessary to make a certain sequence of analysis involving: technological unit establishment, purpose function and optimizing model. Thus, there attaining to the mathematical model of the unit cost, after determination of all the individual calculation articles, regarding the preparatory workings, coal face equipments, materials, energy, workforce, etc. Because of the complexity of the obtained technical and economic model, to determine the optimum sizes of the panel length and top coal height, it was necessary to archive a sensitivity analysis of the unit cost function to the main parameters implied into this mathematical model.

1952 ◽  
Vol 1953 (1) ◽  
pp. 79-105 ◽  
Author(s):  
Ivar Johansson ◽  
Alan Robertson

The progress in animal improvement depends on the accuracy with which the breeding value of each individual in the breed, or herd, is estimated, and how the animals chosen on the basis of our estimates are combined in matings. We are concerned here only with the first part of the problem, i.e. the estimation of breeding values. The estimates are made in regard to certain characters, or traits, which are of particular interest from an economic point of view, and they may be based on the phenotypic merit of the individual, or on the merits of its ancestors or collateral relatives, or on the merits of its progeny, in regard to the character in question. Often a combination of two, or three, or all four methods may be used. Their relative importance depends on the heritability of the character, as will be discussed later.


1989 ◽  
Vol 102 (3) ◽  
pp. 473-483 ◽  
Author(s):  
A. Carducci ◽  
C.M. Avio ◽  
M. Bendinelli

SUMMARYA mathematical model has been developed which allows estimation of the epidemiological and economic effects of different tetanus vaccination strategies. The model was used to simulate the epidemiology of tetanus in italy from 1955 to 1982, and then applied to a district of Tuscany by utilizing data obtained from a seroepidemiological survey carried out in the same area. For this district we simulated vaccination programmes designed to reach, within 1 or 10 years, coverages of 60 or 90% of the population aged over 10 years who had not been exposed to the neonatal vaccination programme. The most effective strategy, from both the epidemiological and economic point of view, seems to be 90% coverage reached in 1 year's time. Benefits would be increased by improving the reliability of vaccinal anamnesis.


Author(s):  
Darina Matisková

This article is about the economics aspects on optimization of components production are nowadays very current issue. Article is about the criteria of economic efficiency of production of mechanical components for machine tools and CNC machines. The machinability of materials is considered to be a parameter which characterizes the machined material in the process of cutting and expresses the degree of machining effectivity in terms of material of a product and is expressed by mathematical model.


Author(s):  
Fiorenza Manzalini

This paper focuses on the entry Fondation, compiled by Anne-Robert-Jacques Turgot and published in 1757 in the Encyclopédie. Turgot analyzes the phenome-non of fondations from the socio-economic point of view. In order to assess whether these ancient institutions were suitable for a society moving towards modernity, he uses public utility as the sole criterion of assessment. According to Turgot, the fondations were an obstacle to free enterprise and free market, as on the one hand they accumulated and immobilized capital by subtracting it from productive and profitable investments and, on the other hand, they provided assis-tance and charity without adequate labour promotion by encouraging idleness. Also for these reasons Turgot is in favour of the suppression of these ancient institutions and he prefers the figure of the individual, active and responsible, or free associations of individuals. However, Turgot's attack on fondations seems only one aspect of his broader criticism of all the institutions that were supporting the ancient social order.


2013 ◽  
Vol 20 (3) ◽  
pp. 463-473 ◽  
Author(s):  
Lenka Lacinová ◽  
Martina Černíková ◽  
Jaroslav Hrabal ◽  
Miroslav Černík

Abstract This article deals with combined abio-bioreductive methods for in-situ removal of chlorinated ethenes. The method is based on the use of bioremediation supported by lactate and chemical reduction using nZVI. The method is compared with the use of the individual methods alone, mainly with nZVI. In an environment with very low permeability a poor contaminant removal efficiency was achieved during repeated application of nZVI (about 50% of the original content of contamination). Separate application of lactate resulted in conversion of PCE to 1,2-cis-DCE, whose degradation occurred very slowly. When using the combined abio-bioreductive method, based on consecutive application of lactates and nZVI, over 75% of the original content of contamination was removed. This article discusses not only the changes in concentrations of contaminants but also pH and ORP. Both methods are also compared from an economic point of view.


2018 ◽  
Vol 33 ◽  
pp. 01048
Author(s):  
Alexandr Orlov ◽  
Irina Chubarkina

The paper is dedicated to main modern trends in the area of high-rise construction. The classification of buildings and structures by height is given. Functional distribution by the height of buildings is presented. A review of positive and negative aspects of high-rise construction from the economic point of view is given. On the basis of the data obtained, it is proposed to build up residential microdistricts in the form of urban blocks. A plan of microdistricts development is presented. It takes into account urban blocks and includes their main characteristics. An economic and mathematical model was developed to carry out a comprehensive assessment of the effectiveness of high-rise construction projects.


2011 ◽  
Vol 57 (No. 12) ◽  
pp. 565-573
Author(s):  
A. Parsakhoo ◽  
A. Hosseini S ◽  
R. Ghaffariyan M

&nbsp;This research deals with productivity and cost of rock disintegration and side casting of materials with the use of a hydraulic hammer mounted on a PC 220 Komatsu crawler excavator, which is used on rocky slopes of Hyrcanian forests of Iran. A continuing time study was applied during the road construction. To estimate the volume of rock disintegration, the average end area equation was used. The increasing cut-slope height decreased productivity. The productivity of hydraulic hammer averaged at 5.5 m<sup>3</sup>&middot;h<sup>&ndash;1</sup> for the mean work volume of 5.07 m<sup>3</sup>&middot;m<sup>&ndash;1</sup>. The unit cost of the system was 7.7 &euro;&middot;m<sup>&ndash;3</sup>. From the economic point of view a new machine with multipurpose system could be recommended for forest road construction operations in rocky areas. &nbsp;


Author(s):  
Evgenia E. Melyukhanova ◽  

Economic and mathematical modelling is used to solve complex economic problems, one of which is to improve the economic efficiency of state activities in the field of sentencing and execution of criminal sanctions. From an economic point of view, researchers focus their attention primarily on the problem of crime. In this regard, useful from the methodological point of view is the economic-mathematical model of crime as outlined by S.A. Kolesnikov which is based on the offender behaviour model. There are three objects in the economic-mathematical model of crime. The first object is an offender, the second one is a victim possessing some asset attractive to an offender, and the third object in the model is the state which can detain and punish an offender. The author has developed and proposed an economic-mathematical model of criminal punishment. Rationality of state activity in the field of sentencing and execution of punish-ment means that the punishment is imposed and executed only if the expected costs of its imposition and execution are less than the amount of negative consequences resulting from the crime (both tangible and intangible). If criminal behaviour is rational, state activity should also be rational. Moreover, if the criminal acts on his own behalf and personally bears the risks arising from the criminal activity, the state acts on behalf of the entire society and may not be exposed to excessive risks and unreasonable costs in the process of punishment. Therefore the rational criminal activity of citizens must be contrasted with the rational punitive activity of the state. In order to rationalise the punitive activity of the state, an economic-mathematical model of criminal punishment should be developed. If the economic-mathematical model of crime is based on the theory of expected utility, then the economic-mathematical model of criminal punishment should be based on the theory of costs, because state activities involving punishment are inevitably accompanied by certain costs. Moreover, there are negative consequences (both tangible and intangible) that result from the crime, which also constitute a cost to society. In conclusion, the author concludes that the economic-mathematical model of criminal punishment makes it possible to determine the efficiency of the state's activities in prescribing and enforcing punishment, therefore, it can be used in the law enforcement activities of state authorities.


2019 ◽  
Vol 144 (04) ◽  
pp. 239-243
Author(s):  
Thomas Mertens

AbstractThe epidemiological effect of vaccination is that it primarily reduces the incidence and prevalence of infectious agents and diseases, providing ideal conditions (also from an economic point of view) for prevention. Goal of vaccination is first the individual protection. Other goals may be “herd immunity”, regional repression and global extinction. The STIKO provides recommendations for the implementation of vaccinations and for the implementation of other measures for the specific prevention of communicable diseases and develops criteria for the differentiation of a customary vaccination reaction and damage to health beyond the usual extent of a vaccination reaction. Earlier vaccination recommendations based on “expert opinion” but today are based on the best available evidence. Current STIKO recommendations include vaccination against seasonal influenza, vaccination against HPV, Tdap booster, tetanus PEP, and vaccine management in practice and among migrants. For the success of the vaccination recommendations, it is first and foremost crucial that the medical profession complies with the obligation to inform about vaccination options and needs vis-à-vis patients or guardians.


2019 ◽  
pp. 22-29
Author(s):  
Н. В. Фрадкіна

The purpose and tasks of the work are to analyze the contemporary Ukrainian mass culture in terms of its value and humanistic components, as well as the importance of cultural studies and Ukrainian studies in educational disciplines for the formation of a holistic worldview of modern youth.Analysis of research and publications. Scientists repeatedly turned to the problems of the role of spirituality in the formation of society and its culture. This problem is highlighted in the publications by O. Losev, V. Lytvyn, D. Likhachev, S. Avierintsev, M. Zakovych, I. Stepanenko and E. Kostyshyn.Experts see the main negative impact of mass culture on the quality approach, which determines mass culture through the market, because mass culture, from our point of view, is everything that is sold and used in mass demand.One of the most interesting studies on this issue was the work by the representatives of Frankfurt School M. Horkheimer and T. Adorno «Dialectics of Enlightenment» (1947), devoted to a detailed analysis of mass culture. Propaganda at all socio-cultural levels in the form is similar in both totalitarian and democratic countries. It is connected, according to the authors, with the direction of European enlightenment. The tendency to unify people is a manifestation of the influence of mass culture, from cinema to pop. Mass culture is a phenomenon whose existence is associated with commerce (accumulation in any form – this is the main feature of education), in general, the fact that it exists in this form is related to the direction of the history of civilization.Modern mass culture, with its externally attractive and easily assimilated ideas and symbols, appealing to the trends of modern fashion, becomes a standard of prestigious consumption, does not require intense reflection, allows you to relax, distract, not teach, but entertains, preaches hedonism as the main spiritual value. And as a consequence, there are socio-cultural risks: an active rejection of other people, which leads to the formation of indifference; cruelty as a character trait; increase of violent and mercenary crime; increase in the number of alcohol and drug addicts; anti-patriotism; indifference to the values of the family and as a result of social orphanhood and prostitution.Conclusions, perspectives of research. Thus, we can conclude that modern Ukrainian education is predominantly formed by the values of mass culture. Namely, according to the «Dialectic» by Horkheimer and Adorno, «semi-enlightenment becomes an objective spirit» of our modern society.It is concluded that only high-quality education can create the opposite of the onset of mass culture and the destruction of spirituality in our society. It is proved that only by realizing the importance of cultivating disciplines in the educational process and the spiritual upbringing of the nation, through educational reforms, humanitarian knowledge will gradually return to student audiences.Formation of youth occurs under the influence of social environment, culture, education and self-education. The optimal combination of these factors determines both the process of socialization itself and how successful it will be. In this context, one can see the leading role of education and upbringing. It turns out that the main task of modern education is to spread its influence on the development of spiritual culture of the individual, which eventually becomes a solid foundation for the formation of the individual. Such a subject requires both philosophical and humanitarian approaches in further integrated interdisciplinary research, since the availability of such research will provide the theoretical foundation for truly modern educational and personal development.


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