NON-INTRUSIVE LOAD MONITORING USING CURRENT HARMONIC VECTORS AND ADAPTIVE FEATURE SELECTION

The non-intrusive load monitoring method presented in this paper uses changes in current harmonic vectors to identify the operational state of appliances. The algorithm based on this feature has low complexity, but it may suffer from an information loss caused by a random fluctuation of the current harmonic vectors. In order to deal with this problem, we propose the algorithm which includes a stage which identifies and select a subset of relevant features in the set of available appliance features. The proposed load disaggregation algorithm is demonstrated through experiments on a representative set of household appliances

Nacionalna moć u uslovima globalizacije

After the fall of the Berlin Wall, the social thought is branded by discussions on globalization. However, there are few papers on the analysis of relations between global processes and state institutions. The goal of authors is to point the changed role of state institutions in the conditions of globalization. The analysis of available sources from this subject area provides the authors with the conclusion that the power of state to influence the chain of events is diminishing. One of the main causes of power deficit is the globalization of financial flows. The loss of control regarding financial operations leaves the state without a significant portion of its revenues. The need to compensate the lost revenues burdens the local population and revenues, which in turn raises internal tensions and system instability. Organic link between state institutions and the interest of citizens is being lost. This situation is particularly favorable for an influx of predatory transnational corporations, which use the existing circumstances to realize their own interests. In this context, small and undeveloped countries, which should resolve the issue of deficit of power by closing mutual arrangements and insisting on the development of global institutional mechanisms are in particular jeopardy.Rasprave o globalizaciji su obeležile društvenu misao nakon pada Berlinskog zida. Međutim, malo je radova posvećenih analizi odnosa na relaciji globalni procesi - državne institucije. Cilj autora je da ukažu na promenjenu ulogu državnih institucija u uslovima globalizacije. Analizom dostupnih izvora iz predmetne oblasti autori su došli do zaključka da je moć uticaja na tok događaja kojom raspolažu države sve manja. Jedan od glavnih uzroka deficita moći je globalizacija finansijskih tokova. Sa gubljenjem kontrole nad finansijskim operacijama države ostaju bez značajnog dela svojih prihoda. Potreba da se nadoknade izgubljeni prihodi opterećuje lokalno stanovništvo i prihode što dovodi do unutrašnjih napetosti i nestabilnosti sistema. Gubi se organska veza između državnih institucija i interesa građana. Situacija posebno pogoduje prodoru predatorskih transnacionalnih korporacija koje koriste postojeće okolnosti za realizaciju svojih interesa. U pomenutom kontekstu posebno su ugrožene male i nerazvijene zemlje koje bi deficit moći trebale da rešavaju putem sklapanja međusobnih aranžmana i insistiranjem na izgradnji globalnih institucionalnih mehanizama

IN PULMONARY EMBOLISM AN INTERPRETATION OF SYSTOLIC BLOOD PRESSURE, TROPONIN (AND OTHER IMPORTANT PARAMETERS) DEPENDS ON THEIR PREVIOUS VALUES AND COMORBIDITIES

We reviewed several important parameters in pulmonary thromboembolism (PTE) and showed how not only absolute values but also relative are relevant in clinical practice. The vast majority of parameters depend both on previous values and co-morbidities; failure to realize this can result in misclassification of a patient and inappropriate treatment. For example, the absolute value of systolic blood pressure (BP) less than 90 mmHg is crucial for urgent treatment (e.g. thrombolysis); obviously, the same admission systolic BP (sBP) of 87 mmHg may not have the same significance if previous usual sBP was also 87 mmHg or it was 220 mmHg. Moreover, cardiac troponin is also very important for the risk stratification; the same troponin concentration ought not to be interpreted equally if it is due to acute pulmonary thromboembolism or if it is chronic and due to e.g. renal failure. The interpretation of important dichotomous parameters (normal or pathologic values) in PTE does depend on previous values (if available) and co-morbidities. This principle should be recognized and used in clinical practice, while risk-stratifying patients

On Possible Cryptographic Optimization of Mobile Healthcare Application

The paper deals with a possible SOA based m-healthcare online system with secure mobile communication between patients and medical professionals with medical and insurance organizations. An example of an Android-based secure mobile client application is presented which can be used in the described secure m-healthcare model and it is experimentally evaluated. In the paper, we focus on possible optimization of cryptographic algorithms implemented in the secure Android mobile client application. The presented experimental results justify that security operations related to X.509v3 digital certificate generation and XML/WSS digital signature creation/verification are feasible on some current smart phones and justify the use of the proposed optimization techniques for implemented cryptographic algorithms

The Plight of Sociology at the University

U tekstu se izveštava o rezultatima socio-empirijskog istraživanja tzv. marksističkog obrazovanja na Univerzitetu u Nišu. Iz obimnog materijala proučavanja ovde se interpretiraju neki podaci vezani za sociologiju, a zanemaruju oni o marksističkoj filozofiji, političkoj ekonomiji i političkom sistemu SFRJ. Sociološka zajednica poseduje institucije za edukaciju svojih pripadnika, ali kao ni jedna druga zajednica dozvoljava prevelik profesionalni nered u svom sektoru. Pravo da se krsti sociologom podjednako ima onaj čija se edukacija odvijala na matičnim fakultetima kao i onaj ko se našao u sociologiji igrom slučaja. Istraživanje je potvrdilo da se na Univerzitetu u Nišu upravo tako nešto zbiva. Ako se za jugoslavensku sociologiju postavlja pitanje koliko je zrela kao nauka nalazi istraživanja pokazuju da je u njoj mnogo opštih mesta, sterilnog pozivanja na autoritete, teorijske poze, kompilacije, ali veoma malo materijala o bazičnim problemima s kojima se sociolozi suočavaju svakodnevno. Sociologija se na Univerzitetu u Nišu predaje i u kombinovanim predmetima sa naslovima »Marksizam i sociologija«, »Marksistička filozofija i sociologija«, »Sociologija i teorija i praksa samoupravljanja«, »Sociologija i filozofija prirodnih nauka«. Pitanje je: ko to treba i da li iko može uspešno da predaje kombinovane predmete? Može li se nastava na kombinovanim predmetima zasnivati na rezultatima naučnoistraživačkog rada? Nisu li zapravo sociolozi kao nastavnici ovih kombinovanih predmeta primorani da kao »univerzalni neznalice« predaju ono za što su nestručni, bitno doprineli udesu sociologije na Univerzitetu u Nišu. Ideološki, eksterni razlog nepovoljnog položaja sociologije je u tezi o neprimerenosti socioloških disciplina koncepciji tzv. integralnog marksističkog obrazovanja. Tako je i sociologija na Univerzitetu u Nišu ustuknula od opšteobrazovnog predmeta koji je bio zastupljen na svim fakultetima i bio tretiran kao matematika na tehničkim fakultetima, do situacije da se bori za svoj dignitet u bezličnom marksističkom obrazovanju i svakojakim veštačkim kombinacijama.The article reports on the results of a socio-empirical research project concerning so-called Marxist education at the University of Niš. From an abundance of data, those referring to sociology are interpreted in this article, and those referring to Marxist philosophy, political economy and the political system of the SFR Yugoslavia are put aside. The sociological community has institutions for educating its members, but as any other community, it does not allow to big a professional disorder within its sector. The right to be christened a sociologist is equally given to both those whose education took place on »parent« faculties, and those who found themselves »in« sociology by chance. This research project confirms that precisely such a process in under way at the University of Niš. If asking ourselves how mature a science Yugoslav sociology is, the results of our research point out that it embodies too many generalities, a sterile reference to authority, theoretical pose, compilation, but very little material concerning fundamental issues sociologists are confronted with daily. At the University of Niš, sociology is also lectured as part of the following composite subjects titled: »Marxism and Sociology«, »Marxist Philosophy and Sociology«, »Sociology and the Theory and Practice of Self-Management«, »Sociology and the Philosophy of Natural Sciences«. The question is: who should and can any one successfully lecture on composite subjects? Can such lecturing be based on research? Haven\u27t sociologists, in fact, as lecturers of these composite subjects, having been compelled, as »universal ignoramuses«, to teach what they have no qualification for, sufficiently contributed to the plight of sociology at the University of Niš? Ideologically, the external reason for such an unpropitious position of sociology can be found in the thesis of the unsuitability of sociological disciplines when the concept of the so-called integral Marxist education is concerned. Thus, at the University of Niš, sociology has also yielded to the »general-education« subject represented at all the faculties, and treated as mathematics at the faculties of technical sciences, and has reached a stage in which it is fighting for dignity surrounded by a nondescript Marxist education and all sorts of artificial combinations

Sliding model of flat die test under the variable contact conditions in the thin sheets deep drawing process

ABSTRACT: The deep drawing technology has a significant place in the contemporary industry. Intensive development of the automotive industry contributes a lot to that fact. With development of the new materials of the poorer machinability and with increase of the technological requirements to the higher level, the necessity for complete control of the forming process is increasing as well. There are significant difficulties in realizing any action during the process duration. In present conditions, only two possibilities are at hand: the blank holding force of the variable intensity and drawing beads of the variable height. Both actions require complex control systems. Contemporary technological problems in deep drawing of parts of the complex geometry can be successfully studied experimentally by means of the physical modeling. The physical model of the contact between the flat surfaces has the dominant space at the flange during the deep drawing process of thin sheets. The emphasis is on realizing the nonlinear dependencies of the contact pressure during the process, as one of the possibilities for the process control. The forming process is usually realized in such a way that all the process parameters and conditions (the blank holding force, deformation rate, etc.) are being set prior to the sliding path of the machine. The concrete investigation shows what effects are realized due to the variable intensities of the blank holding force during the deep drawing process. In addition, it is important to define the functional dependencies of the blank holding force. The basic idea is setting the variable pressure in the contact during the sliding process and monitoring the drawing force (the friction force), the friction coefficient, surface roughness of the thin sheet and the tool. Three different materials were applied, two types of lubricants and four versions of the tool's contact elements. The conducted investigations were of the theoretically-experimental character with focus on the experimental part. In the first part of investigations, the theoretical analysis and critical considerations of existing results were conducted. Then followed forming of the nonlinear and linear functional dependencies of the simultaneous variation of the blank holding force (contact pressure) during the process, depending on the thin sheet sample's path. The specific feature of the test is realization of the nonlinear and linear functions of the contact pressure variation during the process. In the second part of the dissertation is presented the concept and realization of the complex measuring-controlling device. The original experimental tribological test was designed and realized, based on a physical model of the thin sheets strips sliding between the working surfaces, with the objective to enable realization of predefined functions of the contact pressure (the blank holding force). Based on that, the precise quantification of effects of the concrete influences (type of thin sheets, tool parameters and contact conditions) on the drawing force, friction coefficient and variation of the surface roughness of the thin sheet and the tool, was realized. Knowing the nature of the mentioned effects enables improvement of knowledge about different influences of the deep drawing process and provides the possibility for controlling that process. Systematization of these results, besides the scientific has a significant practical value, especially in the area of the new technologies of the metal plastic forming, particularly in the deep drawing of thin metal sheets.REZIME: Tehnologija dubokog izvlačenja zauzima značajno mesto u savremenoj industriji. Intenzivan razvoj automobilske industrije tome veoma doprinosi. Razvojem novih materijala lošije obradivosti i povećanjem tehnoloških zahteva na viši nivo, raste potreba za potpunim upravljanjem procesom oblikovanja. Postoje znatne teškoće u ostvarivanju bilo kakvih dejstava dok proces traje. U sadašnjim uslovima to su samo dve mogućnosti: sila držanja promenljivog intenziteta i zatezna rebra promenljive visine. Oba dejstva zahtevaju složene upravljačke sisteme. Savremena tehnološka problematika dubokog izvlačenja delova složene geometrije može se uspešno eksperimentalno izučavati putem fizičkog modeliranja. Fizički model kontakta između ravnih površina zauzima dominantan prostor na obodu komada pri dubokom izvlačenju tankih limova. Jedna od mogućnosti upravljanja procesom je zadavanje nelinearnih zavisnosti kontaktnog pritiska za vreme njegovog trajanja. Proces oblikovanja se najčešće realizuje tako što se svi parametri i uslovi procesa (sila držanja, brzina deformisanja, i dr.) podešavaju pre početka radnog hoda mašine. Konkretno istraživanje pokazuje kakve efekte ostvaruju promenljivi intenziteti sile držanja za vreme procesa dubokog izvlačenja. Takođe, od bitnog značaja je i definisanje funkcionalnih zavisnosti sile držanja. Osnovna ideja je zadavanje promenljivog pritiska u kontaktu za vreme procesa klizanja i praćenje promene vučne sile (sile trenja), koeficijenta trenja, površinske hrapavosti lima i alata. Primenjena su tri različita materijala, dve vrste maziva i četiri varijante kontaktnih elemenata alata. Sprovedena istraživanja su teorijsko-eksperimentalnog karaktera s težištem na eksperimentu. U prvom delu istraživanja izvodi se teorijska analiza i kritičko sagledavanje dosadašnjih rezultata. Zatim sledi formiranje nelinearnih i linearnih funkcionalnih zavisnosti simultane promene sile držanja (kontaktnog pritiska) tokom procesa, zavisno od hoda uzorka lima. Osobenost testa je ostvarivanje linearnih i nelinearnih funkcija promene kontaktnog pritiska za vreme trajanja procesa. U drugom delu rada, izlaže se koncepcija i realizacija složenog merno-upravljačkog uređaja. Projektovan je i realizovan originalni eksperimentalni tribološki test zasnovan na fizičkom modelu klizanja traka lima između ravnih površina, čiji je cilj da omogući ostvarivanje prethodno definisanih funkcija kontaktnog pritiska (sile držanja). Na osnovu toga izvršeno je precizno kvantifikovanje efekata konkretnih uticaja (vrste lima, parametara alata i kontaktnih uslova) na vučnu silu, koeficijent trenja i promene hrapavosti površina lima i alata. Poznavanje prirode navedenih efekata omogućava unapređenje znanja o uticajima na tok procesa dubokog izvlačenja, i daje mogućnosti za upravljanje tim procesom. Sistematizacija ovih rezultata, pored naučne, ima i značajnu praktičnu vrednost u oblasti novih tehnologija plastičnog oblikovanja metala, posebno u oblasti dubokog izvlačenja tankih limova

The effect of genetic parameters on inheritance of the first pod hight in snap bean - Phaseolus vulgaris L.

In order to research the inheritance, gene effect, combination abilities and genetic variance components, we investigated six divergent snap bean genotypes (Supernor, Darija, Grinkrop, Palanačka rana, Šumadinka and Zora) and their F1 progeny created by diallel crossing without reciprocals. For the trait of height of forming the first pod, variance of average value of parents and hybrids was highly significant. The value of dominant components (H1 and H2) was higher than additive component (D), meaning that dominant genes control the inheritance of number of pods per plant. The average level of domination √Hl/D is higher than 1, pointing to superdomination. Heritability in broader sence amounts 90% pointing to high contribution in inheriting the number of pods per plant

Ishrana i kvalitet mesa

There are numerous factors which influence the quality of pork meat (genetic basis, rearing conditions, preslaughter procedures, carcass treatment, cooling). It is understandable that nutrition is one of the major factors which influence the quantity and quality of meat. Main objective of proper nutrition is the best utilization of the genetic potential of pigs, and obtaining of meat which will satisfy the consumer or be used as raw material in manufacturing of meat products. Quality of pig meat is most often associated with pH value, colour succulence, tenderness, content of intramuscular fat (marbling), sustainability and, in general, acceptability by consumers. In this paper, the effect of certain modifications in pig nutrition on post mortal changes, selected technological properties of meat (pH value, water binding capacity, and colour), content of intramuscular fat, quality of fat and acceptability of meat is presented.Brojni su činioci koji utiču na kvalitet mesa svinja (genetska osnova, uslovi gajenja, postupci pre klanja, klanje, obrada trupa, hlađenje). Razume se da je ishrana jedan od veoma značajnih činilaca koji utiče i na količinu i na kvalitet mesa. Osnovni cilj pravilne ishrane je što je moguće više iskorišćavanje genetskog potencijala svinja, i dobijanje mesa koje će zadovoljiti potrošača ili naći svoju namenu u izradi proizvoda od mesa. Kvalitet svinjskog mesa se najčešće vezuje za pH vrednost, boju, sočnost, mekoću, sadržaj intramuskularne masti (mramoriranost), održivost i, uopšte, za prihvatljivost od strane potrošača. U ovom radu prikazan je uticaj određenih modifikacija u ishrani svinja na postmortalne promene, odabrane tehnološke osobine mesa (pH vrednost, sposobnost vezivanja vode, boja), sadržaj intramuskularne masti, kvalitet masti i prihvatljivost mesa

Eksperimentalno i numeričko istraživanje termo-strujnih procesa u spiralnom naboranom toplotnom apsorberu koncentrisanog zračenja

The utilization of modern paraboloidal concentrators for conversion of solar radiation into heat energy requires the development and implementation of compact and efficient heat absorbers. This research is directed toward innovative design solution that involves the development of heat absorber made of spirally coiled tubes with transverse circular corrugations. The main advantage of the considered design solution is a coupling effect of the two passive methods for heat transfer enhancement - coiling of the flow channel and changes in surface roughness. Investigation of the influence of hydraulic, physical and thermal conditions, as well as the geometry of the spirally coiled corrugated heat absorber, on the local intensity of heat transfer and pressure drop was conducted using modern experimental and numerical methods. Laboratory model of heat absorber was instrumented and mounted in the radiation field. Test section instrumentation included inlet fluid flow rate, pressure drop, inlet and exit fluid temperature and 35 type K thermocouples welded to the surface of the coil. The thermal analysis of experimentally obtained data included consideration of the externally applied radiation field, convective and radiative heat losses, conduction through the tube wall and convection to the internal fluid. The experimental results showed significant enhancement of the heat transfer compared to spirally coilled smooth tubes, up to 240% in the turbulent flow regime. The influence of radiant field intensity and geometrical parameters of corrugations outside the experimental range were investigated using computational fluid dynamics techniques in terms of heat transfer and pressure drop. Finally, the reliable correlations for determining the intensity of convective heat transfer coefficient and pressure drop were obtained for different flow regimes, which are applicable in engineering practice