Energy savings for residential heating in two pairs of buildings achieved by implementation of actually consumed energy measuring

The paper presents results of heating energy consumption measurements in two pairs of buildings in community New Belgrade for two heating seasons. Influence of these measurements on energy savings is also presented. The measurements were carried out during heating seasons 2002/03 and 2003/04 in buildings in Block 34 and 63, connected to the district heating system "Beogradske elektrane". The buildings in each pair have similar architectural and thermal characteristics. One of the buildings in a pair was "test" building and the other "control" one. In the "test" building the energy consumption for heating of each apartment was measured, as well as total energy consumption for the whole building in the substation. Occupants were able to regulate the heating system. In the "control" building the energy consumption was measured only for the whole building, and occupants had almost no impact on heating energy consumption. The comparison of energy consumption for heating in the "test" and "control" buildings is given in the paper, as well as analysis of the influence of energy consumption measurements on the achieved energy savings

A simulation model of assistants’ and technicians’ engagement in processing generated requests at a university

This paper presents a simulation model for the optimization of assistants’ and technicians’ engagement in a university teaching process. This model enables us to obtain the values of important parameters for the analysis of the process; even in the case of complex processes at large university departments, which cannot be easily analyzed using analytical methods. In the case when the number of technicians available is not sufficient to process all generated requests of professors and assistants, the assistants take over the processing of the requests, which cannot be processed immediately by the technicians. The characteristics of the system are compared for three different situations: when all technicians are processing the requests of all assistants and all professors; when technicians and assistants are separated in smaller groups; and when the technicians are processing only the requests of the professors and the assistants from their group

IMPROVEMENT OF QUALITY IN PRODUCTION PROCESS BY APPLYING KAIKAKU METHOD

In this paper, Kaikaku method is presented. The essence of this method is introduction, principles and ways of implementation in the real systems. The main point how Kaikaku method influences on quality. It is presented on the practical example (furniture industry), one way how to implement Kaikaku method and how influence on quality improvement of production process

Estimating the soil erosion and deposition rate using 137Cs tracer method in the catchment of Drenova reservoir (B&H)

There are many limitations associated with traditional approaches to estimation of soil erosion and deposition rates. Recently attention has been focused on 137Cs and successful usage of this isotope in soil erosion studies. This paper presents the results of measurements of 137Cs in soil profiles which were sampled within catchments of Drenova reservoir. The proportional model and a simplified version of the mass balance model were used to estimate the mean soil loss or deposition redistributions rates. The aim of this study is to estimate the soil erosion and deposition rates using 137Cs tracer model, as a support for the results obtained by empirical methodology.Postoje mnoga ograničenja povezana sa tradicionalnim pristupima procene erozije i iznosa akumulacije. U novije vreme pažnja je usmerena na 137Cs i uspešno korišćenje ovog izotopa u studijama o eroziji zemljišta i akumulaciji materijala. U ovom radu su prikazani rezultati merenja 137Cs u zemljištu profila koji su uzorkovani u slivu akumulacije Drenova. Proporcionalni model i pojednostavljena verzija modela bilansa mase korišćeni su za procenu gubitka zemljišta i iznosa akumulacije. Cilj ovog istraživanja je procena erozije zemljišta i iznosa akumulacije koristeći 137Cs kao traser, i to kao proveru i podršku rezultatima koji su dobijeni korišćenjem empirijskih metoda

IoT in a New Age of Unified and Zero-Trust Networks and Increased Privacy Protection

This chapter outlines a first attempt to provide a solution to security and privacy challenges of the Internet of Things. It presents a brief overview of the IoT with particular attention paid to security and data privacy. The chapter highlights security and privacy challenges in order to clarify this issue and lay the foundation for the solution. It draws the outline of the current state of the art in the field of IoT security. The chapter aims to define the use of Unified Secure Communications, Services and Web-Applications as a foundation for home/small/medium network hubs based on existing, tested and verified solutions (e.g. Pi Platform). It presents a zero-trust approach for security and privacy protection. In combination with the specific use case, the chapter demonstrates the applicability of this zero-trust approach in the form of a secure and private interactive intelligent conversational system and paves the way to the final sections on discussion and conclusions

Novel workpiece clamping method for increased machining performance

Naprave kod kojih se sile i momenti nastali u procesu rezanja uravnotežuju silama trenja, nastalim na kontaktima elemenata za baziranje i stezanje s izratkom, su vrlo zastupljene u industriji. Spomenute kontakte, pored ostalog, karakterizira određena popustljivost veza koja je složena funkcija makro i mikrogeometrije kontaktnih parova u sustavu izradak-naprava, sila stezanja i sila rezanja. Pogreške obrade uvelike su posljedica upravo popustljivosti spomenutih veza. U radu se razmatra popustljivost veza između elemenata za stezanje i izratka u slučajevima stezanja uređajem za stezanje s ravnim čelom i specijalno dizajniranog elementa za stezanje. Nakon teorijskih razmatranja izloženi su rezultati eksperimentalnih istraživanja. Rezultati ukazuju na značajne prednosti specijalno dizajniranog elementa za stezanje u odnosu na standardni oblik elementa za stezanje s ravnim čelom. Dobiveni rezultati otvaraju prostor za istraživanja u smislu optimizacije elemenata naprava za stezanje i mogućnosti njihove industrijske primjene.Fixtures which balance cutting forces and torques by the friction forces generated on contact surfaces of locating, clamping elements and workpiece surfaces are widespread in industrial practice. Among other things, these friction contacts are characterized by a certain amount of interface compliance which is a complex function of macro- and microgeometry of contact pairs in the workpiece-fixture system, as well as the clamping and cutting forces. Workpiece machining errors are mostly the consequence of that interface compliance. This paper investigates workpiece-fixture interface compliance in cases where clamping is performed using a standard, and specially designed clamping element. Theoretical considerations are presented, followed by results of experimental investigation. Considerable advantages of the specially designed clamping element compared to its standard counterpart are demonstrated by experiments. The results are a good starting point for a research into optimization of special fixture clamping elements and their wider industrial application

Acute pretreatment with chloroquine attenuates renal I/R injury in rats.

BACKGROUND: Acute kidney injury (AKI) still remains an unresolved problem in pharmacotherapy and renal inflammation is a major factor in its development. Chloroquine, a well-known antimalarial drug, posses pleitropic effects as well: antiinflammatory, anticoagulant and vascular actions. The effects of chloroquine on renal function may involve significant increase in urine flow rate, glomerular filtration rate and sodium excretion, as well as stimulation of nitric oxide synthase. However, its role in experimental models of renal I/R injury is unknown. We aimed to analyze the acute effects of a single-dose intravenous chloroquine administered at three different times in the experimental model of I/R injury in rat. METHODS: Rats were subjected to bilateral renal ischemia (45 min) followed by reperfusion with saline lasting 4 hours. Chloroquine was administered in doses of 0.3 mg/kg i.v. and 3 mg/kg i.v. 30 min before ischemia, 30 min before reperfusion and 5 min before reperfusion. Selected a hemodynamic, biochemical and morphological parameters were followed in the Sham-operated animals and rats subjected to I/R injury and pretreated with saline or chloroquine. RESULTS: Chloroquine (0.3 and 3 mg/kg, i.v.) protected the I/R injured kidney in an U-shaped manner. Both doses were protective regarding biochemical and histological markers of the I/R injury (serum urea, creatinine and fractional excretion of sodium, as well as total histological score, tubular necrosis score and KIM-1 staining score) (P<0.05 vs. corresponding controls, i.e. rats subjected to I/R injury and treated with saline only). The protective effects of the lower dose of chloroquine were more profound. Time-related differences between pretreatments were not observed (P>0.05, all). CONCLUSION: Our study shows for the first time that a single dose of chloroquine (0.3 mg/kg i.v.) could afford significant protection of the injured rat kidney

Continuous controllable balloon dilation: a novel approach for cervix dilation

Abstract Background Cervical dilation using mechanical dilators is associated with various complications, such as uterine perforation, cervical laceration, infections and intraperitoneal hemorrhage. To achieve safe and painless cervical dilation, we constructed a new medical device to achieve confident mechanical cervical dilation: a continuous controllable balloon dilator (CCBD). Methods Controlled pumping of incompressible fluid into the CCBD increases the pressure and outer diameter of the CCBD, continuously dilating the cervical canal. The reliability of the CCBD was confirmed in vitro (testing for consistency and endurance, with no detected risk for breakage) and in vivo. A multi-center clinical study was conducted,with 120 pregnant women randomly assigned to one of three groups: Group I,control group, no dilation;Group II,mechanical dilation, Hegar dilator (HeD); and Group III,CCBD. The tissue material for histological evaluation was obtained from the endocervical mucosa before and after dilation using the HeD or CCBD. Results The CCBD dilations were successful and had no complications in all 40 patients of Group III. The cervical tissue was markedly less damaged after CCBD dilation compared with HeD dilation (epithelium damage: 95% (HeD) vs. 45% (CCBD), P P P Conclusions The CCBD should be used as a replacement for mechanical dilators to prevent uterine and cervical injury during cervical dilation. Trial registration ISRCTN54007498</p