scholarly journals Diagnostic and Prognostic Models for Predictive Maintenance: Multi-Criteria Comparative Analysis

Author(s):  
Mohammed Bouaicha ◽  
◽  
Imad El Adraoui ◽  
Nadia Machkour ◽  
Hassan Gziri ◽  
...  

Predictive maintenance has evolved considerably over the past two decades making this strategy an effective way to monitor the operation of industrial systems, thereby predicting its future states and remaining lifespan. It is therefore developed through a process that begins with the collection of information from the industrial system, the objective of which is its diagnosis or / and its prognosis. This article presents an analysis of single-model and multi-model approaches to the effect of diagnostic and prognostic tasks. This analysis is based on a multi-criteria comparison of the different models in order to provide a clear vision to choose the appropriate approach for predictive maintenance. The relevance of the comparative study is argued by the development of criteria directly impacting performance, reliability, efficiency and mutual cooperation between models. Conclusions are then drawn, in order to identify the appropriate diagnostic and prognostic approach for predictive maintenance.

1968 ◽  
Vol 62 (1) ◽  
pp. 185-204 ◽  
Author(s):  
Paul Shoup

The past decade has witnessed a rapid, but uneven, growth in comparative studies. While certain types of political systems have received the lion's share of attention, others have remained backwaters of comparative research, experiencing little or no development in the application of comparative techniques. The comparative study of communist states, until recently, fell into the latter category—relatively neglected and certainly not enjoying the reputation and prestige of work with newly emerging nations or Western political systems.Now this state of affairs is undergoing a change, or at least the promise of one. In the past several years, the possibility of developing comparative techniques in the study of communist political systems has become the object of growing interest and has provoked not a little discussion and debate.1The opportunities and the problems that face this field—especially in developing empirically oriented comparative analysis—are the subject of the present article.


2020 ◽  
pp. 42-52
Author(s):  
Desislava YORDANOVA-PETROVA

This paper is devoted to the participle system in Bulgarian and Greek, presenting in a comparative plan the formation, meanings, functions and use of the different types of participles in the two languages. The paper focuses on the similarities and differences in the different types of participles, giving information about the frequency of their use in both languages. The traditional types of active and passive participles are considered separately. However, for some of the types of participles there are different opinions whether they should be included in the participle systems of the two studied languages, the article presents the relevant views and arguments of researchers. Such are, for example, the past imperfect active participle and the present passive participle in the Bulgarian language, as well as the present active participle and the aorist active participle in Greek. The present study is the first attempt to present the participle system in Bulgarian and Greek, with the comparison made at the system level in both languages. Apart from the theoretical plan, the conclusions formulated as a result of the comparative study of the participle systems of the two languages would be useful in practice in the assimilation of certain types of Greek participles by Bulgarians learning Greek. In the future, the field of study could be expanded into the comparative analysis of the participle system in Bulgarian and Greek at the level of speech (for example, on the basis of a translation corpus).


Author(s):  
А.З. Хабибуллина

Статья посвящена сопоставительному исследованию жанра элегии и элегизма как самостоятельного модуса художественности в русской и татарской поэзии XIX-начала XX вв. в свете категории времени. Установлено, что элегия не вошла в круг канонических и неканонических жанров татарской литературы начала XX века, что значительно усложняет исходную ситуацию сопоставления национальных литератур. Сделан вывод о том, что исторически русская элегия существовала в художественном пространстве времени, в ее содержании особое звучание имел мотив переживания лирическим субъектом настоящего момента бытия в ценностном свете прошлого (В.И. Козлов, О.В. Зырянов, В.Э. Вацуро, М.Л. Гаспаров). Исследования ученых-востоковедов (Г.Э. Грюнебаум, Л. Масиньон, А.М. Шиммель) показали, что время в сознании восточного поэта как будто стремиться «оставаться на месте»; время здесь не линейное в своей протяженности, оно не определяется различиями границ прошлого, настоящего и будущего. Напротив, в нем особое место уделялось переживанию мгновений, причем не всегда расположенных в необратимой последовательности. Сделан вывод о том, что татарское художественное сознание, испытавшее воздействие традиций литератур Востока, имеет сходные черты мировосприятия, что в значительной мере обусловило уникальность пути становления элегического жанра в национальной литературе. Фактическую основу работы составил сопоставительный анализ элегии А.С. Пушкина «Прощанье» (1830) и стихотворения Дэрдменда «Әгәр барсаң, саба җил, безнең илгә» («Ветер утренний, если летишь в нашу сторону…»). Установлено, что произведение Дэрдменда отличается тонким элегическим звучанием. Последнее можно рассматривать как особый тип художественности, на основе которого возник диалог русской классики и татарской литературы в аспекте ценностной категории времени и ее важнейших художественных свойств. The article is devoted to the comparative study of the elegy genre and elegism as an independent mode of artistic expression in Russian and Tatar poetry of the XIX - early XX centuries in the aspect of tense. It is stated that elegy was not included in the field of canonical and non canonical genres of Tatar literature of the early XXth century and this causes some problems in the original situation of national literary comparison. It is concluded that historically Russian elegy existed in artistic sphere of tense and the motive of the lyric character’s experience of current moment in an aspect of value had a specific sound in its content (V.I. Kozlov, O.V. Zyryanov, V.E. Vatsuro, M.L. Gasparov). The orientalists’ studies (G.E. Griunebaum, L.Masinyon, A.M. Shimmel) showed that tense in the conscience of the oriental poet tends to “stop”; time here is not linear in its length, it is not marked by the differences of the past, present and future. In the contrary, special attention was paid to the experience of moments, not always arranged in an inversible sequence. The author comes to the conclusion that Tatar artistic mentality experienced the influence of oriental literature has similar features in worldview which determines the uniqueness of the way the elegiac genre formed in the national literature. The actual basis of the work is comparative analysis of A.S.Pushkin’s elegy “Farewell” (1830) and poems by Derdmend «Әgәr barsaң, saba җil, bezneң ilgә» (“If you go, morning wind, to our land”). It is stated that poem by Derdmend differs by its subtle elegiac sound. The latter can be viewed as a special type of artistry which serves as the basis for the dialogue of Russian classics and Tatar literature in the aspect of time value category and its most important artistic features.


2020 ◽  
Author(s):  
Johann Johann And Devika

BACKGROUND Since November 2019, Covid - 19 has spread across the globe costing people their lives and countries their economic stability. The world has become more interconnected over the past few decades owing to globalisation and such pandemics as the Covid -19 are cons of that. This paper attempts to gain deeper understanding into the correlation between globalisation and pandemics. It is a descriptive analysis on how one of the factors that was responsible for the spread of this virus on a global scale is globalisation. OBJECTIVE - To understand the close relationship that globalisation and pandemics share. - To understand the scale of the spread of viruses on a global scale though a comparison between SARS and Covid -19. - To understand the sale of globalisation present during SARS and Covid - 19. METHODS A descriptive qualitative comparative analysis was used throughout this research. RESULTS Globalisation does play a significant role in the spread of pandemics on a global level. CONCLUSIONS - SARS and Covid - 19 were varied in terms of severity and spread. - The scale of globalisation was different during the time of SARS and Covid - 19. - Globalisation can be the reason for the faster spread in Pandemics.


2019 ◽  
Vol 27 (2) ◽  
Author(s):  
Mariana Borukova ◽  
Vladimir Kotev

Education is an activity requiring lengthy efforts and perseverance, as well as skills for acquiring information and its creative usage. All this is based on prolonged motivation, directly related to the improvement of the educational development and the consecutive professional realization. Long-term objectives serve as coordinating terms leading to particular goals in the everyday life and thus, behaviour could be rationalized and directed in a longer prospective towards both the past and the future. The aim of the present study is to survey the opinion and personal assessment of the long-term motivation of students from NSA “Vassil Levski”, Sofia and students from Nish, Serbia. The research was conducted from November 2016 to May 2017. It was done among 96 students (45 fourth-year students at NSA and 51 students from the University in Nish). The students had to fill out a test consisting of 10 questions related to their personal assessment of their long-term motivation. The results of the study were processed mathematically and statistically by: variation analysis, relative share, comparative analysis of two independent samples and comparative analysis of the frequency distributions with χ² – the Pearson criterion.According to the generalized conclusions, a higher percentage of the Bulgarian students is directed towards long-term objectives and prospects than the percentage of the Serbian students. Women are more motivated in their long-term development than men but there are not statistically significant differences along all the questions. Athletes’ motivation is higher than the average one for the whole population. We believe, however, that the motivation changes in the course of the studies and we assume it is higher for the students who are about to graduate.


Author(s):  
Zhenxu Zhou ◽  
Hao Nie ◽  
Chunling Dong ◽  
Qin Zhang

Failure Modes and Effects Analysis (FMEA) is a useful tool to find possible flaws, to reduce cost and to shorten research cycle in complex industrial systems. Fault Tree Analysis (FTA) has gained credibility over the past years, not only in nuclear industry, but also in other industries like aerospace, petrochemical, and weapon. Both FMEA and FTA are effective techniques in safety analysis, but there are still many uncertain factors in them that are not well addressed until now. This paper combines FMEA and FTA based on Dynamic Uncertain Causality Graph (DUCG) to solve this issue. Firstly, the FMEA model is mapped into a corresponding DUCG graph. Secondly, FTA model is mapped into a corresponding DUCG graph. Thirdly, combine the above DUCG graphs. Finally, users can modify the combined DUCG graph and calculations are made. This paper bridges the gap between FMEA and FTA by combining the two methods using DUCG. And additional modeling power and analytical power can be achieved with the advantages of the combined DUCG safety analysis model and its inference algorithm. This method can also promote the application of DUCG in the system reliability and safety analysis. An example is used to illustrate this method.


2010 ◽  
Vol 25 (2) ◽  
pp. 395 ◽  
Author(s):  
Inaiá María Moreira de Calvalho ◽  
Gilberto Corso Pereira

En este artículo se analiza la evolución reciente de la segregación socioespacial y la de la conformación urbana en la ciudad de Salvador, a la luz del debate sobre las transformaciones de las metrópolis dentro del capital globalizado. Si bien se reconoce que todas las grandes ciudades terminan siendo alcanzadas por la globalización, en el texto se resalta, sin embargo, que los efectos de ese proceso no son uniformes ni convergen en un modelo único de ciudad. Es necesario considerar la conformación histórica de cada una de ellas, sus instituciones, actores y decisiones políticas locales dentro de una dinámica definida por la continuidad/transformación, donde lo que ya existía condiciona la irrupción de lo nuevo, que en muchos casos ya había comenzado a delinearse en el pasado. Mediante la demostración de la conformación de una metrópoli extremadamente desigual y segregada y la medida en que las transformaciones han agravado tales alteraciones al paso de los últimos años, esta revisión del caso de Salvador se propone exponer algunas reflexiones para entender mejor los efectos del proceso de globalización sobre las grandes ciudades de América Latina. AbstractThis article analyzes the recent evolution of the socio-spatial segregation and urban configuration of the city of Salvador, in light of the debate on the transformations of metropolises within globalized capital. Although it is a well-known fact that large cities end up being absorbed by globalization, the text stresses the fact that the effects of this process are not uniform nor do they converge in a single model of a city. It is essential to  consider the historical moment of each of them, their institutions, actors and local political decisions within a dynamic defined by continuity/transformation, in which what already existed conditions the emergence of what is new, which in many cases, had already begun to be shaped in the past. Through the demonstration of the configuration of an extremely unequal, segregated metropolis, and the extent to which the transformations have aggravated these alterations over the years, this review of the case of Salvador proposes offering some reflections to provide a better understanding of the effects of globalization on major Latin American cities.


2020 ◽  
Vol 20 (3) ◽  
pp. 7-52
Author(s):  
Miroslav Tuđman

The author gives an overview of the history of National Security and the Future (NSF). The first editorial board accepted a clear vision and mission of the NSF. That is why the NSF had to react to the political circumstances in which the journal has operated for 20 years. In the first period, international circumstances and the policy of detuđmanization directly influenced the choice of topics and papers published in the journal. For the past five years, the NSF has paid particular attention to the security of national and European critical infrastructure. A total of 257 texts were published on more than 8,000 pages and authored by 134 authors from 25 countries. The NSF has published studies on historical forgery, information operations, production of "fake news" and contributions to the theory and methodology of intelligence activities.


2021 ◽  
Vol 1 (3) ◽  
pp. 9-36
Author(s):  
Luís Valadares Tavares ◽  
Pedro Arruda

Public procurement is a main issue in the frontline of Governments fighting COVID 19 pandemic as the need for additional and urgent acquisitions as well as the need to consolidate the supply chains and to promote sustainable and innovative procurement have been a source of deep changes and main challenges disturbing public markets and invalidating several assumptions of the traditional public contracting. In this paper, the development of appropriate public policies to cope with these challenges is studied following the approach suggested by several authors and including four stages: a Stage on Facts and Issues where the main challenges and conditions are studied, the Options Stage to describe which polices and procedures can be adopted, a Values Stage stating the main values to be pursued and, finally, a Policies Stage including the selection of the recommended policies. The analysis of the challenges and facts includes the study of a taxonomy of short and longer term needs and the available options are based on the comparative study of procedures ruled by the European Directives on Public Procurement approved on 2014. The major values to be respected include the principle of competition which is a major institutional principle of the European Treaty and of the Directives as well as the goal of promoting sustainable and innovative public procurement. Several indicators are suggested to describe the application of the public procurement policies adopted across EU and their comparative analysis is presented using the TED data for contracts concerning COVID 19. The case of Portugal is discussed and final remarks about the recommended public policies are also included herein.


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