An architect's relation to structure: Analysis of Pinki cultural sports center by Ivan Antić

Architecture represents the synthesis of form, function and construction. In the works of the architect Ivan Antić this can be read at the first view of the building. A master in designing movement through an object, Antić constantly developed the relationship between function and form, as well as between function and construction. A detailed analysis of his work, projects and drawings, gives insight to these relations, making them clear. The observer can see the architect's logic and simplicity in designing even the most complex buildings. The relationship between the design concept and the way the structure manifests itself in his projects will be presented in this paper. The logic behind the design of Pinki Cultural Sports Center, with emphasis on structure, as well as the relationship between the architect and the engineer can be seen throughout this paper

Time dependent system state probabilities of single server queuing system with infinite queue

Analitički izraz za verovatnoće stanja u zavisnosti od vremena, jednokanalnog sistema masovnog opsluživanja sa neograničenim redom M/M/1, je izveden. Izraz je izveden nalaženjem granične vrednosti izraza za verovatnoće stanja u zavisnosti od vremena jednokanalnog sistema masovnog opsluživanja sa ograničenim redom M/M/1/K, kada broj mesta u redu teži beskonačnosti, u slučaju kada je sistem na početku rada prazan. Pri izvođenju korišćene su samo elementarne matematičke operacije.Analytical expression for time dependent system state probabilities of single server queuing system with infinite queue capacity M/M/1 is derived. Expression is derived by finding the limit value of expression for time dependent system state probabilities of single server queuing system with finite queue capacity M/M/1/K, when number of places in the queue tens to infinity, in the case that system is empty at the beginning. Only elementary mathematical operations are used

Time dependent system state probabilities of single server queuing system with infinite queue

Analitički izraz za verovatnoće stanja u zavisnosti od vremena, jednokanalnog sistema masovnog opsluživanja sa neograničenim redom M/M/1, je izveden. Izraz je izveden nalaženjem granične vrednosti izraza za verovatnoće stanja u zavisnosti od vremena jednokanalnog sistema masovnog opsluživanja sa ograničenim redom M/M/1/K, kada broj mesta u redu teži beskonačnosti, u slučaju kada je sistem na početku rada prazan. Pri izvođenju korišćene su samo elementarne matematičke operacije.Analytical expression for time dependent system state probabilities of single server queuing system with infinite queue capacity M/M/1 is derived. Expression is derived by finding the limit value of expression for time dependent system state probabilities of single server queuing system with finite queue capacity M/M/1/K, when number of places in the queue tens to infinity, in the case that system is empty at the beginning. Only elementary mathematical operations are used

Analysis of risk factors for the development of atherosclerosis in patients with chronic kidney disease

Dosadašnja ispitivanja su pokazala da je ateroskleroza česta, asimptomatska komplikacija hronične bolesti bubrega, prisutna u njenom ranom stadijumu i prediktor je teških kardiovaskularnih komplikacija. Cilj naše studije je bio da se istovremenim određivanjem koncentracije biomarkera endotelne disfunkcije (IL-1, IL-6, TNF-α, homocistein, malonildialdehid) u serumu, merenjem debljine intima-medija kompleksa u zidu karotidnih arterija, procenom sistolne i dijastolne funkcije leve komore srca, utvrdi značaj kao i senzitivnost i specifičnost ovih biomarkera za otkrivanje ateroskleroze u ranom stadijumu hronične bolesti bubrega. Gore navedena ispitivanja stvorila bi uslove za otkrivanje stadijuma hronične bolesti bubrega u kome bolesnici imaju najveći rizik od razvoja ateroskleroze. Materijal i metode istraživanja: Istraživanje je sprovedeno po tipu prospektivne studije preseka na 100 bolesnika koji su pregledani u Kabinetu za nefrologiju Vojnomedicinske akademije-Beograd, kod kojih je dijagnostikovana hronična bolest bubrega. U zavisnosti od stepena jačine glomerulske filtracije bolesnici su podeljeni u pet grupa, a kontrolnu grupu su činili bolesnici sa klirensom kreatinina ≥ 90 ml/min/1,73m2. Kod svih bolesnika je ispitivan uticaj stepena bubrežne funkcije na koncentraciju biomarkera endotelne disfunkcije u serumu proinflamatorni citokini (IL-1, IL-6,TNF-α), homocistein, malonildialdehid, uticaj koncentracije biomarkera endotelne disfunkcije na debljinu intima-medija kompleksa u zidu karotidnih arterija, uticaj stepena bubrežne funkcije na debljinu intima-medija kompleksa u zidu karotidnih arterija, stepen povezanosti ehokardiografskih parametara sistolne i dijastolne funkcije leve komore srca i koncentracije biomarkera endotelne disfunkcije. Rezultati istraživanja: Generalno, rezultati ispitivanja ukazuju na međusobnu povezanost koncentracije biomarkera endotelne disfunkcije u serumu (IL-1, IL-6, TNF-α, homocistein, malonildialdehid), debljine intima-medija kompleksa u zidu karotidnih arterija, sistolne i dijastolne funkcije leve komore srca sa stepenom funkcije bubrega. Sa opadanjem funkcije bubrega povećava se koncentracija malonildialdehida i homocisteina u serumu. Utvrđena je statistički značajna korelacija između koncentracija IL-1 i stepena bubrežne funkcije (sa opadanjem funkcije bubrega povećava se koncentracija IL-1 u serumu). Sa opadanjem funkcije bubrega povećava se i debljina intima-medija kompleksa u zidu karotidnih arterija. Bolesnici sa uznapredovalom hroničnom bolesti bubrega imaju veći stepen zadebljanja intima-medija kompleksa u zidu karotidnih arterija, u odnosu na kontrolnu grupu bolesnika i grupu bolesnika sa blažim oblicima hronične bolesti bubrega. Stepen funkcije bubrega utiče na funkciju leve komore srca. Sa opadanjem funkcije bubrega povećava se i broj bolesnika sa dijastolnom disfunkcijom leve komore. Zbog velike učestalosti patoloških vrednosti biomarkera endotelne disfunkcije i kod bolesnika bez aterosklerotičnih promena, njihova pozitivna prediktivna vrednost (potvrda oboljenja) je u korektnom opsegu (80-92,6%), ali je mogućnost otkrivanja bolesnika bez aterosklerotičnih promena bitno umanjena (negativna prediktivna vrednost se kreće u opsegu od 0 do 33,3%). Stoga se čini da su neophodni dodatni napori u oblasti pretkliničkih i kliničkih ispitivanja kako bi se pronašli senzitivniji i specifičniji biomarkeri za otkrivanje ateroskleroze u ranom stadijumu hronične bolesti bubrega. Zaključak: Rano otkrivanje ateroskleroze sprečilo bi i usporilo nastanak teških kardiovaskularnih komplikacija kod ovih bolesnika čime bi se poboljšao kvalitet, dužina životnog veka i smanjili troškovi lečenja kasnih komplikacija.Background/Aim: Recent studies have shown that atherosclerosis is common and often asymptomatic complication of chronic kidney disease, present in its early stages and is a predictor of serious cardiovascular complications. The aim of our study was determination of the concentration of biomarkers of endothelial dysfunction (IL-1, IL-6, TNF-α, homocysteine, malondialdehyde) in serum, measuring the intima-media thickness of the carotid artery wall and assessment of systolic and diastolic left ventricular function, and determination of the importance, sensitivity and specificity of these biomarkers for the detection of atherosclerosis in the early stages of chronic kidney disease. The above tests also would create conditions for the detection the stages of chronic kidney disease in which patients are at greatest risk of developing atherosclerosis. Materials and methods of research: The study was conducted as a prospective crosssectional study in 100 patients with chronic kidney disease, examined in the ambulatory department of Nephrology Military Medical Academy of Belgrade. Depending on the level of GFR, patients were divided into five groups. Control group consisted of patients with a creatinine clearance > 90 ml/min/1.73m2. In all patients, the influence of renal function on the degree of concentration of biomarkers of endothelial dysfunction [proinflamatory serum cytokines (IL-1, IL-6, TNF-α)], homocysteine, malonildialdehid, the impact of the concentration of biomarkers of endothelial dysfunction in the intima-media thickness of the carotid wall artery, the influence of the degree of renal function on the intima-media thickness of the carotid artery wall, and the corelation of echocardiographic parameters of systolic and diastolic left ventricular function and concentrations of biomarkers of endothelial dysfunction were investigated. Research results: Overall, the our results indicate the connection between concentrations of biomarkers of endothelial dysfunction in serum (IL-1, IL-6, TNF-α, homocysteine, malondialdehyde), intima-media thickness of the carotid artery wall, systolic and diastolic left ventricular function with the degree of kidney function. With the decline of renal function, there is increases in concentration of malondialdehyde and serum homocysteine. Also, there is a statistically significant correlation between the concentrations of IL-1 and a renal function (with declining kidney function increases the concentration of IL-1 in serum). With declining kidney function, there is also a increase of the thickness of the intima-media complex in carotid arteries. Patients with advanced chronic kidney disease have a higher degree of thickening of the intima-media wall in the carotid arteries, compared with the control group and the group of patients with milder forms of chronic kidney disease. The degree of renal dysfunction affects the function of the left ventricle of the heart. Decrease of renal function increases the number of patients with diastolic dysfunction of the left ventricle. Due to the high incidence of pathological levels of biomarkers of endothelial dysfunction in patients without atherosclerotic lesions, their positive predictive value (confirmation diseases) is in the correct range (80 to 92.6%), but the ability to detect patients without atherosclerotic lesions is reduced significantly (negative predictive value is in the range of 0 to 33.3%). Therefore, it appears that additional efforts are needed in the field of preclinical and clinical studies in order to find a more sensitive and specific biomarkers for the detection of atherosclerosis in early stages of chronic kidney disease. Conclusion: Early detection of atherosclerosis would prevent and reduce the occurrence of serious cardiovascular complications and improve the quality, length of life and reduce the cost of treatment of late complications in these patients

Design of intelligent manufacturing systems by using artificial intelligence

Intenzivan razvoj krajem osamdesetih, tokom devedesetih godina 20. veka i posebno posle 2000. godina, a koji je definitivno uspostavio i novu oblast istraživanja u proizvodnom inženjerstvu pod nazivom inteligentni tehnološki sistemi, ukazuje na pozitivan trend u pravcu ostvarivanja novih proizvodnih tehnologija u 21. veku. U vremenu kada je automatizacija proizvodnje gotovo dostigla svoj trenutni maksimum, tehnološka migracija od fleksibilnih ka inteligentnim tehnološkim sistemima i zadovoljavanje sve većih potreba globalnog tržišta ostvaruje se novim, multidisciplinarnim pristupom, baziranim na primeni naprednih biološki inspirisanih paradigmi 21. veka. Projektovanje tehnoloških procesa, terminiranje tehnoloških procesa, kao i terminiranje transportnih sredstava su među tri najvažnije funkcije inteligentnih tehnoloških sistema. Varijantnost u pogledu tehnoloških operacija obrade dela, kao i u pogledu alternativnih proizvodnih resursa (mašina alatki, alata, orijentacija alata), utiče na to da najveći broj delova u savremenim tehnološkim sistemima može imati više alternativnih tehnoloških procesa obrade. Iz tog razloga, određivanje optimalnih tehnoloških procesa obrade delova predstavlja jedan od najvažnijih ciljeva u ovoj naučnoj oblasti istraživanja. Kao i projektovanje tehnoloških procesa, terminiranje fleksibilnih tehnoloških procesa sa terminiranjem transportnih sredstava pripada klasi nedeterminističkih polinomnih problema, pa je stoga fokus istraživanja u okviru predmetne doktorske disertacije usmeren na razvoj biološki inspirisanih tehnika veštačke inteligencije u optimizaciji funkcija inteligentnih tehnoloških sistema, a u cilju povećanja njihove proizvodnosti, efikasnosti i ekonomičnosti...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..

TOWARDS FLEXIBLE HOUSING: BASIC DESIGN PRINCIPLES

In times of radical social transformations, the demand for flexibility of space can be identified as one of the strategic priorities of maintaining the urban environment. In the context of social, economic and environmental sustainability, housing must imply an integrated ability to respond to programme changes, which can be achieved through the concept of flexibility. By identifying and applying certain design principles, it is possible to prevent the problem of functional obsolescence and unsuitability of the living environment that modern cities are facing. The apartment as an immediate living environment is the most direct indicator of the degree of adaptability of the physical surrounding to modern human needs. The analysis of basic design principles, using an example of flexible apartment, examines the spatial correlations and laws of the relationship between elements of the plan, which provides the basis for the authors to draw the conclusions about the reality of applying this concept in practice

Job crafting in Serbia: Serbian mixed-method validation of the Job Crafting Scale

Cilj ovog istraživanja je bila validacija srpske adaptacije Skale preoblikovanja posla (eng. the Job Crafting Scale - JCS), primenom kombinacije kvalitativnog i kvanitativnog pristupa u okviru tri studije na ukupnom uzorku od 832 osobe zaposlene u različitim sektorima privrede. Preoblikovanje posla (eng. job crafting) predstavlja ponašanje na poslu koje je usmereno na preoblikovanje radnih zadataka tako da se pojača i održi motivacija za rad. U prvoj studiji smo proveravali razumevanje stavki kao i prilagođenost sadržaja stavki našoj kulturi. U drugoj studiji smo proverili faktorsku sturukturu JCS skale, kao i pouzdanost i validnost faktora. U trećoj studiji smo testirali invarijantnost predloženih modela između uzorka druge i treće studije, kao i kriterijumsku validnost analiziranjem korelacija JCS skale i posvećenosti poslu (eng. work engagement). Kvalitativna analiza je pokazala da većina ajtema uspešno prenosi željeno značenje. Posebnu pažnju treba obratiti na interpretaciju skorova dimenzije smanjivanje ometajućih zahteva na poslu pošto ovi ajtemi mogu ukazivati na ponašanja koja se ne opažaju kao poželjna. Imajući u vidu ukupnu pouzdanost, invarijantnost četvorofaktorskog modela drugog reda i kriterijumsku valjanost, verzija skale sastavljana od 21 ajtema se može smatrati validnom merom preoblikovanja posla u Srbiji. Takođe, ova studija je ukazala da kratka forma srpske verzije JCS skale od 12 ajtema ima zadovoljavajuća psihometrijska svojstva i da može biti validna lokalna mera preoblikovanja posla.The aim of the current study was to validate the Serbian adaptation of the Job Crafting Scale (JCS), applying both qualitative and quantitative approaches, within three studies totalling 832 employees from different industries. Job crafting is work behaviour aimed at modifying job tasks in order to enhance and maintain work motivation. In Study 1, we have tested the understanding of all items and their possible cultural embeddedness. In Study 2, we have tested the JCS factor structure, factors' reliability and validity. In Study 3, we have tested the invariance of the proposed models (Study 2 and Study 3 models) and criterion validity by analysing the correlation between the JCS and work engagement. Qualitative analysis has revealed that the majority of items transferred the intended meaning. Special care should be taken in interpreting the decreasing hindering job demands dimension scores, since these items might point toward behaviours that were not perceived as positive. With its overall reliability, second-order four-factor model invariance and criterion validity, originally composed 21-item JCS could be considered to be a valid instrument for assessing job crafting in Serbia. The present study has also shown that the 12-item JCS-Serbian short version has satisfactory psychometric properties and that it could be considered as a valid local job crafting scale

Integration of process planning, scheduling, and mobile robot navigation based on triz and multi-agent methodology

U radu je predstavljena metodologija za razvoj softverske aplikacije za integraciju projektovanja tehnološkog procesa, terminiranja proizvodnje i navigacije mobilnog robota u tehnološkom okruženju. Predložena metodologija je bazirana na primeni teorije inventivnog rešavanja problema i multiagentske metodologije. Matrica kontradikcije i inventivni principi su se pokazali kao efektivan alat za otklanjanje kontradiktornosti u koncepcijskoj fazi razvoja softvera. Predložena multiagentska arhitektura sadrži šest agenata: agent za delove, agent za mašine, agent za optimizaciju, agent za planiranje putanje, agent za mašinsko učenje i agent mobilni robot. Svi agenti zajedno učestvuju u optimizaciji tehnološkog procesa, optimizaciji planova terminiranja, generisanju optimalnih putanja koje mobilni robot prati i klasifikaciji objekata u tehnološkom okruženju. Eksperimentalni rezultati pokazuju da se razvijeni softver može koristiti za predloženu integraciju, a sve u cilju poboljšanja performansi inteligentnih tehnoloških sistema.This paper presents methodology for development of software application for integration of process planning, scheduling, and the mobile robot navigation in manufacturing environment. Proposed methodology is based on the Russian Theory of Inventive Problem Solving (TRIZ) and multiagent system (MAS). Contradiction matrix and inventive principles are proved as effective TRIZ tool to solve contradictions during conceptual phase of software development. The proposed MAS architecture consists of six intelligent agents: job agent, machine agent, optimization agent, path planning agent, machine learning agent and mobile robot agent. All agents work together to perform process plans optimization, schedule plans optimization, optimal path that mobile robot follows and classification of objects in a manufacturing environment. Experimental results show that developed software can be used for proposed integration in order to improve performance of intelligent manufacturing systems

Workplace bullying in Serbia: The relation of self-labeling and behavioral experience with job-related behaviors

Workplace bullying has been identified as a widespread problem in contemporary organizational research. The aim of the paper was to acquire theoretically based and comparable findings about workplace bullying in Serbia: to explore the behavioral experience and self-labeling approaches (applying the Negative Acts Questionnaire - Revised, NAQ-R) and their relationship with job-related behaviors. The sample comprised 1,998 employees. Prevalence rates of workplace bullying based on self-labeling and behavior experience approaches overlap significantly (70% of employees operationally identified as bullied had also labeled themselves as bullied). Both the self-labeling and behavioral experience approach showed significant correlations with job-related behaviors (perceived threat to a total job, absenteeism, intention to leave, and perceived productivity). Previously bullied, presently bullied and non-bullied employees differed significantly on all four job-related behaviors, with large effect size for the intention to leave and medium effect size for the perceived threat to a total job. The findings support combining self-labeling and behavioral experience approaches in workplace bullying research. [Projekat Ministarstva nauke Republike Srbije, br. 179018

Komparativno ispitivanje efikasnosti bazične, lasero i fitoterapije kod pacijenata sa hroničnom parodontopatijom

The aim of the investigation that was conducted as clinical prospective study was to establish efficacy of the basic, low level laser therapy (LLLT) and phytotherapy in patients with chronic periodontitis. Different approaches in the treatment of chronic periodontitis were compared. Beside basic (causal) therapy, that represents the ‟‟gold standard” for the treatment of chronic periodontitis, LLLT and phytotherapy were performed. The study included 111 subjects divided into 4 groups. The first, the second and the third group was constituted as follows: 30 patients with chronic periodontitis, who received basic periodontal treatment (I group), combined basic and phytotherapy (II group) and combined LLLT and basic therapy (III group), for five consecutive days. Clinical parameters were measured before intervention, after the fifth treatment and after a month. All subjects received oral hygiene instructions and full-mouth periodontal treatment (professional removal of dental plaque and calculus, followed by curettage of periodontal pockets). Afterwards, in group II, phytotherapy was applied (Tinctura paradentoica ® Institut “Dr Josif Panĉić”, Beograd), while in group III, Kavo LLLT (980 nm, 0.2 W, 6 J/cm2) was applied. Subgingival samples were collected at baseline and after the fifth treatment to identify following bacterial species: Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythensis and Treponema denticola. Gingival swabs were taken, and direct smears were prepared on slides for cytomorphometric analysis. The fourth group included 21 periodontally healthy subjects in good general health. The results were compared by clinical examination (oral hygiene indices, gingival and periodontal indices), polymerase chain reaction (PCR) method for detection of periodontopathogenic bacteria and cytomorphometric analysis. The evaluation using clinical parameters showed better results in group III, there LLLT was applied. Comparing the values of nuclear area after therapy, it was established that their values were statistically significantly higher in the basic therapy group, compared to the combined therapy groups (II and III), independently (p < 0,001). After treatment, the following bacterial species were found less frequently (Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythensis and Treponema denticola) in all studied groups, compared to before treatment, except bacteria Tannerella forsythensis, that was found more frequently in the basic therapy group. In the combined therapy groups (II and III), a statistically significant decrease in the prevalence of bacteria was observed for Tannerella forsythensis and Treponema denticola (p < 0,001). However, in the LLLT group, statistically significant decrease in the prevalence of the remaining bacteria was observed for the following: Aggregatibacter actinomycetemcomitans and Prevotella intermedia (p < 0,05), as well as Porphyromonas gingivalis (p < 0,01). Based on previous findings, it could be concluded that combined LLLT and basic therapy had better short - term outcomes compared to the basic and phytotherapy as well as basic therapy itself