Design of intelligent manufacturing systems by using artificial intelligence

Интензиван развој крајем осамдесетих, током деведесетих година 20. века и посебно после 2000. година, а који је дефинитивно успоставио и нову област истраживања у производном инжењерству под називом интелигентни технолошки системи, указује на позитиван тренд у правцу остваривања нових производних технологија у 21. веку. У времену када је аутоматизација производње готово достигла свој тренутни максимум, технолошка миграција од флексибилних ка интелигентним технолошким системима и задовољавање све већих потреба глобалног тржишта остварује се новим, мултидисциплинарним приступом, базираним на примени напредних биолошки инспирисаних парадигми 21. века. Пројектовање технолошких процеса, терминирање технолошких процеса, као и терминирање транспортних средстава су међу три најважније функције интелигентних технолошких система. Варијантност у погледу технолошких операција обраде дела, као и у погледу алтернативних производних ресурса (машина алатки, алата, оријентација алата), утиче на то да највећи број делова у савременим технолошким системима може имати више алтернативних технолошких процеса обраде. Из тог разлога, одређивање оптималних технолошких процеса обраде делова представља један од најважнијих циљева у овој научној области истраживања. Као и пројектовање технолошких процеса, терминирање флексибилних технолошких процеса са терминирањем транспортних средстава припада класи недетерминистичких полиномних проблема, па је стога фокус истраживања у оквиру предметне докторске дисертације усмерен на развој биолошки инспирисаних техника вештачке интелигенције у оптимизацији функција интелигентних технолошких система, а у циљу повећања њихове производности, ефикасности и економичности...At the beginning of the 21st century, a methodology that provides technological migration from flexible manufacturing systems to intelligent manufacturing systems is definitely based on biologically inspired methods. Process planning, scheduling and scheduling of internal transport systems (mobile robot) belong to most important functions of intelligent manufacturing systems. A variety of manufacturing operations together with a variety of alternative manufacturing resources (machine tools, cutting tools, tool access directions, etc.) provide that most jobs in the modern manufacturing systems may have a large number of alternative process plans. For that reason, obtaining an optimal process plan according to all alternative manufacturing resources as well as alternative operations has become a very important task in flexible process planning problem research. As process planning, scheduling function also belongs to NP hard (non deterministic polynomial problem) which means that time exponentially increases with the increase of alternative machine tools, tools and TADs. Therefore, development of biologically inspired algorithms for optimization of proposed functions is the main focus of research efforts in this thesis. The doctoral dissertation is related to the implementation of three methodologies for conceptual design of intelligent manufacturing systems: axiomatic design theory is used for conceptual design of material transport which includes transport of raw material, goods and parts; inventive principles of TRIZ methodology are used as effective tool to define, analyze and solve integration problems at the conceptual design phase and multi-agent methodology is used to facilitate integration of manufacturing functions. The doctoral dissertation is related to the development and experimental verification of 6 novel optimization algorithms for process planning: (i) genetic algorithms - GA algorithm (section 6.1), (ii) simulated annealing - SA (section 6.2), (iii) hybrid GA-SA (section 6.3), (iv) modified particle swarm optimization algorithm - mPSO (section 6.4), (v) chaotic particle swarm optimization algorithm - cPSO..

Boiling heat transfer modelling a review and future prospectus

This paper reviews the current status of boiling heat transfer modelling, discusses the need for its improvement due to unresolved intriguing experimental findings and emergence of novel technical applications and outlines the directions for an advanced modelling approach. The state-of-the-art of computational boiling heat transfer studies is given for: macro-scale boiling models applied in two-fluid liquid-vapour interpenetrating media approach, micro-, meso-scale boiling computations by interface capturing methods, and nano-scale boiling simulations by molecular dynamics tools. Advantages, limitations and shortcomings of each approach, which originate from its grounding formulations, are discussed and illustrated on results obtained by the boiling model developed in our research group. Based on these issues, we stress the importance of adaptation of a multi-scale approach for development of an advanced boiling predictive methodology. A general road-map is outlined for achieving this challenging goal, which should include: improvement of existing methods for computation of boiling on different scales and development of conceptually new algorithms for linking of individual scale methods. As dramatically different time steps of integration for different boiling scales hinder the application of full multi-scale methodology on boiling problems of practical significance, we emphasise the importance of development of another algorithm for the determination of sub-domains within a macro-scale boiling region, which are relevant for conductance of small-scale simulations

Boiling heat transfer modelling a review and future prospectus

This paper reviews the current status of boiling heat transfer modelling, discusses the need for its improvement due to unresolved intriguing experimental findings and emergence of novel technical applications and outlines the directions for an advanced modelling approach. The state-of-the-art of computational boiling heat transfer studies is given for: macro-scale boiling models applied in two-fluid liquid-vapour interpenetrating media approach, micro-, meso-scale boiling computations by interface capturing methods, and nano-scale boiling simulations by molecular dynamics tools. Advantages, limitations and shortcomings of each approach, which originate from its grounding formulations, are discussed and illustrated on results obtained by the boiling model developed in our research group. Based on these issues, we stress the importance of adaptation of a multi-scale approach for development of an advanced boiling predictive methodology. A general road-map is outlined for achieving this challenging goal, which should include: improvement of existing methods for computation of boiling on different scales and development of conceptually new algorithms for linking of individual scale methods. As dramatically different time steps of integration for different boiling scales hinder the application of full multi-scale methodology on boiling problems of practical significance, we emphasise the importance of development of another algorithm for the determination of sub-domains within a macro-scale boiling region, which are relevant for conductance of small-scale simulations

Simply Prepared Magnesium Vanadium Oxides as Cathode Materials for Rechargeable Aqueous Magnesium Ion Batteries

Vanadium-oxide-based materials exist with various vanadium oxidation states having rich chemistry and ability to form layered structures. These properties make them suitable for different applications, including energy conversion and storage. Magnesium vanadium oxide materials obtained using simple preparation route were studied as potential cathodes for rechargeable aqueous magnesium ion batteries. Structural characterization of the synthesized materials was performed using XRD and vibrational spectroscopy techniques (FTIR and Raman spectroscopy). Electrochemical behavior of the materials, observed by cyclic voltammetry, was further explained by BVS calculations. Sluggish Mg2+ ion kinetics in MgV2O6 was shown as a result of poor electronic and ionic wiring. Complex redox behavior of the studied materials is dependent on phase composition and metal ion inserted/deinserted into/from the material. Among the studied magnesium vanadium oxides, the multiphase oxide systems exhibited better Mg2+ insertion/deinsertion performances than the single-phase ones. Carbon addition was found to be an effective dual strategy for enhancing the charge storage behavior of MgV2O6. © 2022 by the authors

Levels of insulin, insulin-like growth factor-I and thyroid hormones in relation to the body condition score changes in periparturient dairy cows

The objective of this study was to determine the levels of insulin, insulin like growth factor I (IGF-I) and thyroid hormones in relation to the body condition score (BCS) of periparturient dairy cows. The study was carried out on twenty Holstein-Friesian dairy cows with average milk production of 7000 L/305 days in the previous lactation, parity ranging from 2-4. All cows were BCS scored during the early dry period, 7±3 days before and after parturition. Based on the BCS at the early dry period, cows were divided in two groups: cows with high BCS (3.75- 4.25, HBCS, n=10), and cows with moderate BCS (2.75-3.75, MBCS, n=10). Blood samples were taken at the time of BCS evaluation. Concentrations of insulin, IGF-I, triiodothyroinine (T3) and thyroxine (T4) were determined by radioimmunoassay (RIA, INEP-Zemun, Serbia). Statistical differences between mean values were determined using Student t-test (p<0.01). Mean BCS values at early dry period were significantly different compared to two other periods (p<0.01) within both groups, but BCS was similar in both groups at 7±3 days after calving (2.69±0.67:2.62± 0.27, p>0.05). IGF-I level in HBCS cows at days 7±3 before calving was significantly higher (16.28±3.07:11.76±2.28, p<0.01), with a reverse relationship after calving (3.77±1.64:8.46±2.37, p<0.01). Insulin level was significantly lower at 7±3 days before calving in HBCS cows (16.26±4.60:20.18±4.96mIU/L, p<0.05). Thyroid hormones levels were significantly lower in HBCS group et all examined periods. [Projekat Ministarstva nauke Republike Srbije, br. III 46002 i br. 31003

Spectral parameters for finger tapping quantification

A miniature inertial sensor placed on fingertip of index finger while performing finger tapping test can be used for an objective quantification of finger tapping motion. Temporal and spatial parameters such as cadence, tapping duration, and tapping angle can be extracted for detailed analysis. However, the mentioned parameters, although intuitive and simple to interpret, do not always provide all the necessary information regarding the subject's motor performance. Analysis of frequency content of the finger tapping movement can provide crucial information about the patient's condition. In this paper, we present parameters extracted from spectral analysis that we found to be significant for finger tapping assessment. With these parameters, tapping's intra-variability, movement smoothness and anomalies that may occur within the tapping performance can be detected and described, providing significant information for further diagnostics and monitoring progress of the disease or response to therapy

A quality of life assessment and the correlation between generic and disease-specific questionnaires scores in outpatients with chronic liver disease-pilot study

Introduction. Chronic liver diseases (CLD) are an important cause of morbidity and mortality in general population. The aim of this study was to analyze potential differences between patients with CLD and healthy control group, and to estimate the severity of CLD by using simple questionnaires: general health questionnaire (GHQ-12) and chronic liver disease questionnaire (CLDQ). Methods. A cross-sectional pilot study was performed in Zemun Clinical Hospital during years 2014 and 2015. Sixty participants were divided into 4 groups (15 per group): chronic alcoholic hepatitis, other chronic hepatitis, liver cirrhosis, and healthy control group. Entire study population chose one of four offered answers of structured questionnaires GHQ-12 and CLDQ, based on which mean model of end-stage liver disease (MELD) and Child-Turcotte-Pugh (CTP) scores were calculated. Results. Mean GHQ12 and CLDQ scores were 10.5 and 5.21 +/- 1.11 respectively. Regarding certain CLDQ domain scores, a significant difference between alcoholic and non-alcoholic hepatitis groups in the worry domain was observed. Mean MELD score was 7.42 +/- 2.89 and did not differ between chronic hepatitis groups, while mean CTP score was 5.73 +/- 0.88. A statistically significant correlation was observed between GHQ12 and CLDQ scores (rho = -0.404, p LT 0.01), but not between subjective and objective scores. Conclusions. Mean GHQ12 and CLDQ scores pointed out to general psychological no-distress condition of the studied participants, as well as scarcely expressed CLD-specific complaints. Mean MELD and CTP scores indicated stable chronic liver diseases, with low three-month mortality rates in the cases of chronic hepatitis, as well as determination to Child A group in the case of liver cirrhosis

Design of Protective Structures for Active Archeological Sites

This paper presents a structural design methodology in order to find the best possible solution of protective structures for active archeological sites. Besides the typical demands for construction on these sites which arise from the typology and the level of protection of cultural heritage, active archeological sites require a structural solution with regard to time and direction of further excavation. The hypothesis is that modular spatial structures which are easily assembled or disassembled, and have the ability to be extended in one or more directions, are the most functional solution for these sites. This paper shows the analysis of several types of spatial structures based on the requirements of active archeological sites. It explores the possibilities of structural systems derived from multiplication of one primary element of structure, their material and joints between elements. The most adequate assembly of the entire structure is supposed to be found in the interdependency of the load and the dimension of the element’s cross- section, in a suitable geometric configuration. The focus of the analysis is on structures made of short-bearing elements which have the advantage of the efficiency of transport and assembling. One of the design criteria for this methodology is that the structural system itself looks simple and elegant in order to complement the archeological site. This is shown in the paper through the analysis of patterns in which these structures are assembled. The aim is to correlate the position of the elements in the structural system, the dimensions of cross-section, and the lengths of the straight beams which form the spatial structure in order to find a simple, functional and economical solution for protective structures at active archeological sites. The conclusion shows the advantages and disadvantages of the design methodology presented in the paper, as well as the discussion about the analyzed spatial structures. This type of methodology that systematizes various design criteria from different fields of research engages the problem of design of protective structures for archeological sites and opens up new questions for further research

Uticaj vrste klona prokupca i postupka vinifikacije na sadržaj rezveratrola u vinu

The focus of this study was to investigate the effects of clones (subvarieties) of autochthonous Serbian grape variety Prokupac, along with the influence of vinification method on the content of transand cis-resveratrol as well as on total phenolic content (TPC) in wines. Wines were made from four clones of Prokupac variety (PR1, 40/1, PR6 and PR7) by application of different periods of maceration duration (1, 5 and 10 days). The effects of different species of selected wine yeasts and glucosidase enzymes on the quantity of resveratrol and TPC in wine made from PR6 variety were also investigated. The content of trans-resveratrol varied from 0.27 mg/L to 1.46 mg/L. The highest content of resveratrol was determined in Prokupac clone PR6, and the lowest in PR7 clone. An increase in resveratrol and TPC content was observed in all clones when the duration of maceration was prolonged. Wine produced by application of b enzyme preparation and 299 yeast had the highest concentration of total resveratrol (4.23 mg/L). The TPC was the highest in the wine made by combined application of yeast 299 and OE enzyme. The obtained results showed that by adequate selection of varieties, prolonged duration of maceration, application of appropriate species of yeast and enzyme preparations, it is possible to increase the content of resveratrol and other phenolic compounds in wine.Cilj ovog istraživanja bio je da se ispita uticaj različitih klonova autohtone srpske sorte Prokupac kao i postupak vinifikacije na sadržaj transi cisrezveratrola i sadržaj ukupnih polifenola (SUP) u vinima. Vina su proizvedena od četiri klona sorte Prokupac (PR1, 40/1, PR6 i PR7) primenom različitih dužina trajanja maceracije (1, 5 i 10 dana) za svaki klon. Takođe je ispitivan uticaj različitih izabranih kvasaca i enzimskih preparata glikozidaza na sadržaj rezveratrola i SUP u vinima proizvedenim od klona PR6. Sadržaj transi cisrezveratrola je određen HPLC metodom sa UV detektorom uz prethodnu tečno čvrstu ekstrakciju (SPE). Određivanje SUP je urađeno metodom po FolinČokalteu. Sadržaj transrezveratrola je bio od 0,27 mg/L do 1,46 mg/L. Najviši sadržaj rezveratrola je bio u klonu PR6 dok je najniži PR7. Povećanje sadržaja rezveratrola i SUP je primećeno kod svih klonova kada je maceracija duže trajala. Vino proizvedeno primenom enzimskog preparata glikozidaza b i kvasca 299 je imalo najviši sadržaj ukupnog rezvertrola (4,23 mg/L). Najviši SUP je bio u vinima proizvedenim primenom enzimskog preparata glikozidaza OE i kvasca 299. Dobijeni rezultati ukazuju da je izborom odgovarajućeg klona, dužine maceracije, primene odgovarajućeg kvasca i enzimskog preparata moguće povećati sadržaj rezveratrola i drugih fenolnih jedinjenja u vinu

Profili masnih kiselina i antioksidativna svojstva sirovih i sušenih oraha

Background: Walnuts consumption produces beneficial effects on human health. Health-promoting benefits are dedicated to its desirable fatty acid profile and high content of antioxidants. Heat treatment of walnuts may alter their fatty acid composition and antioxidant capacity. Aim: In general the aim of this work was to compare fatty acids profiles and antioxidative properties of raw and dried walnuts at 60 °C for 12 hours. Methodology and results: FA profiles were analyzed using gas chromatography. Antioxidative capacities of walnut samples were determined by DPPH and ABTS tests. There were no significant differences in fatty acid profiles comparing dried and raw walnuts. The most abundant fatty acid was linoleic with mean content of 61.38 ± 1.11% in raw and 62.40 ± 0.99% in dried walnuts. Walnuts oil contained 10.64 ± 0.46% and 10.49 ± 0.81% of a-linolenic acid (ALA) in raw and dried walnuts, respectively. Antioxidative capacity of methanolic extracts showed no difference comparing raw and dried walnut by DPPH and ABTS test. Heat treatment at 60 °C for 12h induced no change in fatty acid profiles of walnuts and led to minor decrease in antioxidative capacity measured only by ABTS test. Conclusion: We suggest that drying process in our experiment did not decreased nutritional capacity which is mostly mediated by conservation of fatty acids content in walnuts.Dijetarni unos oraha povezuje se sa brojnim pozitivnim efektima na zdravlje. Svoj efekat na zdravlje orasi ostvaruju zahvaljujući povoljnom masnokiselinskom sastavu i visokom sadržaju antioksidanasa. Zagrevanje oraha moglo bi dovesti do promena u masnokiselinskom sastavu i uticati na antioksidativni kapacitet. Cilj ovog rada bio je da se uporede masnokiselinski profili i antioksidativni status svežih i oraha sušenih na 60 °C u trajanju od 12 sati. Masnokiselinski sastav analiziran je gasnom hromatografijom. Antioksidativni kapaciteti uzoraka oraha odreðivani su DPPH i ABTS testovima. Utvrðeno je da nije bilo promena u masnokiselinskim profilima posle sušenja oraha na 60 °C u trajanju od 12 sati. Najzastupljenija masna kiselina bila je linolna sa sadržajem od 61.38 ± 1.11% u sirovim i 62.40 ± 0.99% kod sušenih oraha. Ulje oraha sadržalo je 10.64 ± 0.46% i 10.49 ± 0.81% a-linolenske kiseline (ALA) u svežim i sušenim orasima, respektivno. DPPH testom nije utvrđeno da postoje razlike u antioksidativnom potencijalu metanolnih ekstrakata oraha sušenih u odnosu na sveže kao ni sa ABTS testom. Naš eksperimet je pokazao da proces sušenja oraha nije smanjio njihov nutritivni kapacitet što je verovatno posredovano očuvanjem sadržaja masnih kiselina