Mechanical Engineering eJournal最新文献

{"title":"Improvement of Operation Modes of the Evaporator of the Absorption Refrigerating Unit","authors":"Oleksandr Titlov, Daniyorbek Adambayev, O. Vasyliv","doi":"10.21303/2461-4262.2020.001354","DOIUrl":"https://doi.org/10.21303/2461-4262.2020.001354","url":null,"abstract":"Absorption refrigeration units (ARU), which are part of absorption refrigeration devices (ARD) with a natural working fluid (water, ammonia and hydrogen) have a number of unique qualities. These qualities include: noiselessness, high reliability and long life; the possibility of using several energy sources in one device. At the same time, ARDs have increased energy consumption compared to similar compression models, and this does not allow them to expand their presence in the market of household refrigeration equipment. \u0000The ARU evaporator provides a predetermined temperature level in the chambers of the refrigeration appliance and the required cooling capacity. In this regard, it is relevant to search for the operating modes of the evaporator that provide the ARU maximum energy efficiency, which is the aim of this work. \u0000The thermal conditions of the direct-flow three-pipe design of the evaporator are simulated. The calculated ratio for a once-through evaporator is obtained taking into account the assumption of the adiabaticity of the evaporation process, when all the heat of the phase transition is used to cool the incoming flows of the purified vapor-gas mixture (VGM) and liquid ammonia to a minimum temperature. \u0000The analysis of the results of calculating the operating modes of the evaporator made it possible to determine the directions of ways to increase the energy efficiency of both the evaporator itself and the ARU in general: \u0000   a) preliminary cooling of the purified VGM flow at the inlet of the adiabatic section of the evaporator with an under-recovery of up to 5 °C and up to 10 °C; \u0000   b) preliminary cooling of the liquid ammonia flow at the inlet of the adiabatic section of the evaporator with an under-recovery of up to 5 °C for all ARU types; \u0000   c) increasing the purification degree of the VGM flow in the absorber allows increasing the temperature of the purified VGM flow at the inlet of the adiabatic section of the evaporator by 4...6 °C, i. e. to reduce the costs of useful cooling capacity for pre-cooling by 10...15 %","PeriodicalId":404477,"journal":{"name":"Mechanical Engineering eJournal","volume":"450 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131424729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving a Method to Analyze the Requirements for an Information System for Consistency","authors":"Nataliya Vasiltcova, Iryna Panforova, Olga Neumyvakina","doi":"10.15587/1729-4061.2020.205518","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.205518","url":null,"abstract":"Modern representations of characteristics of functional requirements virtually have no formalized descriptions. That is why the application of the existing methods for the analysis of requirements faces the problems of formal confirmation or refutation of the fact that a functional requirement has an appropriate characteristic. These problems are particularly pronounced in the analysis of functional requirements for consistency. To eliminate these problems, the task was set to develop formalized descriptions of the situations of the complete and partial inconsistency of knowledge-oriented descriptions of functional requirements and based on the resulting descriptions, to improve the existing method for analysis of functional requirements for consistency of created or modified information system. The knowledge-oriented frame-based description was used as a formal description of the analyzed functional requirement for an information system. In the course of solving this problem, the formalized descriptions of the situations of complete contradiction and partial inconsistency of descriptions of the frames of analyzed functional requirements were developed. It was shown that the situation of complete contradiction is a particular case of a situation of the partial inconsistency of descriptions of analyzed frames. This result was the basis for the improved method for analysis of separate frames of descriptions of functional requirements for consistency. The improved method makes it possible not only to identify situations of complete contradiction and partial inconsistency of analyzed frames but also to quantify the degree of the identified inconsistency. The initial and the improved methods were tested during the analysis of the functional requirements of the problem of planning the individual activity of the academic and teaching staff of a higher education institution. Three typical situations that may arise from the analysis of functional requirements for consistency were considered. It was shown that the improved method makes it possible to find more errors in the descriptions of functional requirements","PeriodicalId":404477,"journal":{"name":"Mechanical Engineering eJournal","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126193384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of the Method for Estimating the Technical Condition of Gas Pumping Units by Their Accelerating Characteristic","authors":"M. Gorbiychuk, O. Zamikhovska, Leonid Zamikhovsky, V. Pavlyk","doi":"10.15587/1729-4061.2020.206476","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.206476","url":null,"abstract":"Analysis of failures of gas pumping units (GPU) installed on the Urengoy-Pomary-Uzhhorod transcontinental gas pipeline showed that failures of automatic control systems of automatic gas pumping units occupy the second place (up to 40 %) of the total number of failures. It is shown that the well-known methods for monitoring the technical condition of the mechanical part of a gas pumping unit can’t be used to control the operability of automatic control systems and automatic gas control unit components. Among the well-known methods for monitoring the operability of automatic control systems of a gas pumping unit as a dynamic system, the most promising methods are those based on the analysis of its transient process (accelerating characteristic) with some typical input exposure. The theoretical justification of the developed method for monitoring the performance of the automatic control system of the gas pumping unit is presented, the diagnostic feature of which is the value of the areas of accelerating characteristics. The structure of the transfer function and its parameters were determined by the area method (Simoiu method). To implement the method in MatLab, software was developed that allows one to determine the parameters of the transfer function from the experimental start-up curve of the gas pumping unit and the size of the area limited by its transient function. The technique of experimental studies of the proposed method for monitoring the efficiency of the automatic control system of a gas pumping unit type GTK-25i example is given. Further implementation of the proposed method requires determining the conditions of its operability and parallel monitoring of the technical condition of the mechanical units of the gas pumping unit in order to exclude their influence on the result of monitoring the state of the automatic control unit of the gas pumping unit","PeriodicalId":404477,"journal":{"name":"Mechanical Engineering eJournal","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125429914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Banking 4.0: ‘The Influence of Artificial Intelligence on the Banking Industry & How AI Is Changing the Face of Modern Day Banks’","authors":"Dr. Navleen Kaur, Supriya Lamba Sahdev, Dr. Monika Sharma, Laraibe Siddiqui","doi":"10.34218/ijm.11.6.2020.049","DOIUrl":"https://doi.org/10.34218/ijm.11.6.2020.049","url":null,"abstract":"Artificial intelligence (AI), from time to time called machine intelligence is simulation of human intelligence in machines. It is the intellect exhibited by machines, in contrast to the natural knowledge demonstrated by humans. From Siri to self-driving cars, AI is progressing at a rapid pace.<br><br>Artificial intelligence consists of generally two fundamental ideas. First it involves studying human brains like how their thought process works and secondly it helps representing those processes through machine learning. Artificial Intelligence in finance is more than about chat bots. Artificial Intelligence has taken over numerous sectors including banking industry. The principal thought behind this investigation was to comprehend the impact of AI on present day banking.<br><br>This research mainly focuses on the concept of AI in the field of banking, how it has brought revolutionary changes in banking and its impact on human manpower. As we are aware that humans tend to commit errors, but the world is evolving so does the innovations, there is lack of skilled talents required to handle the automation. Several routine and manual tasks which were earlier performed by the humans are now being replaced by the automated machines with advance technology. Given that the business is experiencing noteworthy change at a quick pace, this research is a preview of the current applications of AI in the banking industry and how it is changing the face of banking in India.","PeriodicalId":404477,"journal":{"name":"Mechanical Engineering eJournal","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125209236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Features of Mathematical Modeling of Electromagnetic Processing of Bulk Materials","authors":"Yuriy Zaporozhets, N. Batechko, S. Shostak, N. Shkoda, E. Dibrivna","doi":"10.15587/1729-4061.2020.206705","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.206705","url":null,"abstract":"The article notes the features of applying the general equations of mathematical physics of an elliptic type in problems of modeling specific phenomena of the interaction of electromagnetic fields with elements and particles of an inhomogeneous dispersed medium. Such phenomena take place in installations for the separation of organic and mineral raw materials or the electromagnetic treatment of grain, seeds, etc. This is relevant, because the usual approach to the formulation of mathematical models in these problems, which is mainly based on differential equations of field theory in a simplified form, does not always adequately reflect the physical essence of the mentioned phenomena. Therefore, it limits the possibilities of an in-depth study of the influence of many factors determining the final results of separation and electromagnetic processing (EMP) processes. In the present work, an alternative approach is proposed based on the use of integral equations of field theory, which is based on the concept of primary and secondary field sources and can significantly reduce the order of the system of equations for the numerical implementation of algorithms for solving EMP problems, and the total amount of necessary computing resources. With this approach, local parameters of the field in interaction with individual particles and their influence on one another become available for calculation. This aspect is essential for determining the technological characteristics of EMP production installations. The presented mathematical model, in contrast to the common simplified approaches to determining the field parameters and ponderomotive forces acting on the particles of matter in the field, adequately reflects the physical laws of the distribution of potentials and electric field strength of real charges and induced sources. Due to this, it clearly reproduces the mechanism of the formation of the main components of mechanical forces acting on the polarized body from the side of the electric field as a whole, through the densities of elementary forces with which the field acts on surface charges induced in dielectric bodies in the field of action of the fields. Such a mathematical model is a universal and compact tool for analysis, design, and optimization of various installations and devices that use an electric field and its electromechanical interaction with the medium and individual bodies","PeriodicalId":404477,"journal":{"name":"Mechanical Engineering eJournal","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133251438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Observed Time Difference of Arrival Based Position Estimation for LTE Systems: Simulation Framework and Performance Evaluation","authors":"A. Alhafid, S. Younis","doi":"10.15587/1729-4061.2020.201382","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.201382","url":null,"abstract":"Precise user equipment (UE) location is paramount for the reliable operation of location-based services provided by mobile network operators and other emerging applications. In this paper, the Long Term Evolution (LTE) network positioning performance based on mobile assist Observed Time Difference of Arrival (OTDoA) method is considered. The received signal time difference (RSTD) measurements are estimated by the UE using dedicated position reference signal (PRS) transmitted in the downlink frame where the reported time measurements are used by the network for location calculation. A simulation framework for the position estimation in LTE networks is presented where the LTE downlink communication link is implemented. The correlation-based method for the time of arrival measurement is used for the implementation of OTDoA. The simulation framework provides different configurations and adjustments for the system and network parameters for evaluating the performance of LTE positioning using OTDoA over multipath fading channels. Different simulation scenarios are conducted to identify the influence of various parameters of LTE system and positioning procedure setup on the positioning accuracy. Simulation results demonstrated that the positioning accuracy is highly affected by the channel fading condition where the accuracy of time of arrival measurements is deteriorated in severe fading environments; however, the positioning accuracy can be significantly improved by increasing the positioning sequences involved in the estimation process either in the frequency domain or in the time domain.","PeriodicalId":404477,"journal":{"name":"Mechanical Engineering eJournal","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124503685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Data Science and the Decline of Liberal Law and Ethics","authors":"Sebastian Benthall, Jake Goldenfein","doi":"10.2139/ssrn.3632577","DOIUrl":"https://doi.org/10.2139/ssrn.3632577","url":null,"abstract":"The law and ethics of Western democratic states have their basis in liberalism, and this extends to legal regulation and ethical discussion of technology and businesses doing data processing. We argue that these forms of regulation and ethical analysis are largely incompatible with the techno-political and techno-economic dimensions of data science. Over the course of the 20th century, computer science, cognitive psychology, operations research, statistics and other fields, have converged on an understanding of utility-maximizing agency that, combined with a neo-liberal legal configuration, guarantees the supremacy of private corporations over individuals that would know and defend their own individual interests. In particular, platforms have inverted the relationship between individuals and the market, making the former public and the latter private. It is this crisis of liberalism, and the degraded status of the individual in their relationship to data science platforms, that is at the heart of data science ethics. Therefore, data science ethics cannot be addressed from within liberalism; it requires new theory that builds on data science itself.","PeriodicalId":404477,"journal":{"name":"Mechanical Engineering eJournal","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130822124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Direct Atomistic Modeling of Solute Drag by Moving Grain Boundaries","authors":"Raj Kiran Koju, Y. Mishin","doi":"10.2139/ssrn.3634175","DOIUrl":"https://doi.org/10.2139/ssrn.3634175","url":null,"abstract":"Abstract We show that molecular dynamics (MD) simulations are capable of reproducing the drag of solute segregation atmospheres by moving grain boundaries (GBs). Although lattice diffusion is frozen out on the MD timescale, the accelerated GB diffusion provides enough atomic mobility to allow the segregated atoms to follow the moving GB. This finding opens the possibility of studying the solute drag effect with atomic precision using the MD approach. We demonstrate that a moving GB activates diffusion and alters the short-range order in the lattice regions swept during its motion. It is also shown that a moving GB drags an atmosphere of non-equilibrium vacancies, which accelerate diffusion in surrounding lattice regions.","PeriodicalId":404477,"journal":{"name":"Mechanical Engineering eJournal","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114618642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cracks, Porosity and Microstructure of Ti Modified Polymer-Derived Sioc Revealed by Absorption-, XRD- and XRF-Contrast 2D and 3D Imaging","authors":"H. Van Swygenhoven, Pradeep V. Warriam Sasikumar, PhD, Lorenz Hagelüken, Dario F. Sanchez, PhD, Nicola Casati, PhD, Federica Marone, PhD, Gurdial Blugan, PhD, Jürgen Brugger, Prof., Malgorzata Grazyna Makowska, Ph.D.","doi":"10.2139/ssrn.3606805","DOIUrl":"https://doi.org/10.2139/ssrn.3606805","url":null,"abstract":"Abstract Morphology, phase composition, cracks and porosity are investigated in monolithic Ti modified SiOC polymer-derived ceramics pyrolyzed at 1000 °C and 1400 °C using synchrotron X-ray full field absorption-contrast tomographic microscopy and scanning XRF- and XRD-contrast microscopy. Samples pyrolyzed at 1000 °C show a crack-free structure, but pyrolysis at 1400 °C results in formation of cracks and at higher Ti content also shows porosity. Tomography revealed the formation of a layered morphology that varies in terms of crystallographic structure and/or Ti stoichiometric concentration. The microstructural observations and electrical conductivity are discussed in terms of pyrolysis temperature and Ti content.","PeriodicalId":404477,"journal":{"name":"Mechanical Engineering eJournal","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127959352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"AI as a Legal Person?","authors":"Dr Eliza Mik","doi":"10.2139/ssrn.3616732","DOIUrl":"https://doi.org/10.2139/ssrn.3616732","url":null,"abstract":"Cyclical advancements in artificial intelligence (AI) are usually accompanied by theories advocating the granting of legal personhood to sophisticated, autonomous computers. This chapter criticizes such theories as incorrect—a possible result of legal scholars being seduced by incomprehensible technical terminology, sensationalistic stories in the popular press, and ‘creative’ photo filters that transform our faces into animals. Discussions as to when computers should be recognized as persons are, logically, outside of the scope of intellectual property law. The granting of legal personhood is not premised on the existence of consciousness, intelligence, or creativity. Recognizing an entity as a legal person is a normative choice dictated by commercial expediency, not the result of fulfilling any technical criteria. While it is necessary to acknowledge the blurring of borders between art and (computer) science, as well as the increase in the technological sophistication of the tools used by authors and inventors, it is also necessary to state that even an exponential increase in ‘computer creativity’ will not sever the link between the computer and its user. Before discarding the idea of legal personhood for ‘creative algorithms’ once and for all, the chapter explores the relationships between autonomy and creativity. In particular, it places technical terms such as ‘AI’ and ‘autonomy’ in their original context and criticizes uninformed attempts to imbue them with normative connotations.","PeriodicalId":404477,"journal":{"name":"Mechanical Engineering eJournal","volume":"206 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125736893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}