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The development of smart technologies in the building sector provides better insight into occupant behavior and brings new opportunities for energy and performance management. Smart technological solutions are being applied in various segments of building performance. Within heating and cooling systems, new trends are directed toward developing novel operation and regulation strategies based on the input from sensory devices. Proposed studies through the literature are trying to provide more comfortable environmental conditions for the occupants in the buildings, putting users as the crucial factors for system design while considering also rational energy usage. Because smart buildings are increasing as the area of research, this paper aims to systematize the methods for the smart optimization of the heating/cooling systems in the buildings and provide an overview of the proposed solutions available in the literature (i.e., Scopus database) and highlight novel trends in smart management of the heating/cooling systems. The overview was performed with respect to the type of heating/cooling system, controlling mechanism/principle, data collection devices, and corresponding interface, as well as the location of the building in each study. Finally, the energy-saving potential of the proposed systems was tackled in the overview as well.

Following the user-centric trends in the smart building paradigm, a perspective for future research and development is found to be in the personalized thermal comfort modelling. The technological solutions used in the thermal comfort evaluation methodology have a direct impact on the acquired data provided to the model. Therefore, they affect the model’s overall accuracy and are a crucial factor in thermal comfort modelling. Implementing smart technologies and developing personalized thermal comfort models in the smart buildings brings a possibility to achieve energy savings on the one hand, and the satisfaction of the users could be improved on the other hand. In order to investigate the application of the personal thermal comfort models in the smart building context, this work provides overview of the smart technologies used for monitoring of thermal comfort parameters in buildings to provide current state-of-the-art in this segment of smart buildings.

High-performance buildings are sensitive to the occupant’s impact with respect to the energy consumption of the various building systems or individual technologies used in buildings. Thermal comfort has got an important role in the occupant’s satisfaction level, and it is directly linked with building energy performance. Development of the smart and Internet of Things (IoT) based technologies allowed the possibility for further advancements in the field of personal thermal comfort, leading towards potential energy savings in the buildings via smart and advanced control of building energy systems. In this work, the conceptual approach, as well as the results of the short-term field investigation, were presented for the case of office buildings. The wearable sensors (smart bracelets) were attached to the occupants, enabling continuous monitoring of various influential parameters on the personal thermal comfort, such as skin wrist temperature and heart rate. The environmental thermal comfort parameters were also simultaneously measured (air temperature, relative air humidity and CO2 concentration), together with conducted field survey (subjective response from occupants) to find a correlation between subjective response and experimental readings. The proposed approach allowed a more complex and precise evaluation of the personal thermal comfort where gained field data could be useful for modelling of the personal thermal comfort, as an important basis for smart regulation of the building energy systems.

Thermal comfort (TC) is an important issue in buildings, since it has impact on the occupant’s health, ability to work or function effectively, satisfaction with the environment etc. Development of the smart technologies in the building sector brings new opportunities for the energy management approach. User-centric technological solutions are being applied in various segments of the building performance. Within heating and cooling systems, new trends are directed towards development of the personal thermal comfort models. Developed models are trying to provide individualized environmental conditions for the occupants in the buildings, putting user’s internal parameters i.e. physiology and preferences as the crucial information for system design. This work provides major findings related to the current state-of-the-art in personal thermal comfort detection as well as description of the methodology of the field investigation of personal thermal comfort in office building with wearable sensors. Collected information could be useful for modelling the personal thermal comfort as important basis for smart regulation of the building energy systems.

Thermal comfort (TC) is an important issue in buildings, as it has impact on the occupant’s health, ability to work or function effectively, satisfaction with the environment etc. Globally acknowledged standards for thermal comfort - ASHRAE 55 and ISO 7730, use the metabolic rate as one of the basic personal inputs in the TC calculations together with the clothing insulation and air temperature, relative air humidity, mean radiant temperature and air velocity as environmental parameters. It is rather simple to measure the values of environmental variables using the appropriate sensors, while accurate measuring of personal variables such as metabolic rate and clothing insulation requires more complex approach. This paper provides an overview of existing technologies and methods related to the different approaches of measurement of the metabolic rate in the context of TC in buildings.

Suvremena informatička tehnologija omogućuje prilagodbe u prenošenju nastavnih sadržaja individualnim potrebama studenata, unaprjeđuje se kvaliteta i dostupnost nastavnih sadržaja te se potiče studente na samostalan rad, samoregulirano učenje i usvajanje gradiva na višim razinama kognitivne obrade sadržaja. Po principima mješovitog učenja i poučavanja – engl. blended learning ; studenti prve godine studija fizioterapije dio svojih nastavnih obveza predmeta Fizioterapijska procjena izvršavaju u virtualnom okruženju, na poslužitelju Moodle Zdravstvenog veleučilišta. Studentima je predstavljen izvedbeni plan predavanja i pristup prezentacijama na temu predavanja. Sve prezentacije prate odgovarajuća poglavlja u udžbeniku Fizioterapijska procjena koji je studentima dostupan u e-izdanju na platformi e-student. Studenti imaju obvezu riješiti tematski test, čime se potvrđuje usvojenost sadržaja pojedine tematske jedinice. Svi tematski testovi tvore bazu od 300 ispitnih pitanja. U okviru tradicionalne – engl. place based nastave vježbi u praktikumu studentima se dodjeljuje timski tematski praktični zadatak čije izvršavanje svaka skupina studenata objavljuje na poslužitelju Moodle. U videoprezentaciji studenti opisuju i demonstriraju postupke opservacije i palpacije anatomskih struktura segmenta, testiranje selektivne tenzije tkiva, procjenu anatomskog integriteta i opsega pokreta u zglobu, antropometriju i procjenu mišićne funkcije. Tijekom primjene modela blended learning ostvarena je dostupnost nastavnih materijala putem interneta, pružene su smjernice za učenje te mogućnost samoprovjere usvojenosti nastavnog sadržaja. Videoprezentacijom tematskog zadatka studenti demonstriraju primjenu odgovarajućih postupaka mjerenja i procjene te razinu usvojenosti praktične vještine. Uz stručne, usvajaju se opće kompetencije poput samostalnog iniciranja, planiranja i provedbe zadatka te primijene informacijsko-komunikacijske tehnologije.

The genus Lepidium (Brassicaceae) includes about 175 different plant species strikingly characterized by glucosinolates (GLs) as molecular tags [1]. The cultivated Lepidium latifolium L. (perennial pepperweed) was investigated to decipher its GL profile using 1) an indirect method with GC-MS analysis of the GL degradation volatile products (mostly isothiocyanates and nitriles) obtained by hydrodistillation and organic solvent extraction, and 2) a direct method with LC-MS analysis of intact GLs. GC-MS analysis showed that the most abundant GLs were sinigrin and glucotropaeolin, and a minor one was glucocochlearin. LC-MS analysis confirmed the presence of the above-mentioned GLs but also detected 4-methoxyglucobrassicin. In recent years, studies have been directed towards isothiocyanates due to the broad range of their biological effects [1-3]. Taking that into account, L. latifolium leaf extract and hydrodistillate containing GL degradation products were evaluated for their anticarcinogenic activity against two human tumor cell lines - glioblastoma cell line LN-229 and bladder cancer cell line UM-UC-3. Their antimicrobial activity against pathogenic and food spoilage bacteria and fungi was also assessed. The extract and distillate exhibited very similar anticarcinogenic and antibacterial activities, but with a somewhat better effect for the extract. On the other hand, both extract and distillate were found to exert very strong antifungal activity against Candida albicans (MIC50 8 and 16 µg/mL).

U ovom radu obrađena je tema „Tehno-ekonomska analiza isplativosti fotonaponskih elektrana na području RH“. U početku je kratko opisan princip rada fotonaponskih tehnologija i njihov razvoj kroz povijest. Zatim je dat pregled komercijalno dostupnih fotonaponskih tehnologija kao i njihove primjene. Nakon toga slijedi kratak osvrt na okolnosti i poticanje FN tehnologija u RH kroz pregled njenih geografskih obilježja, mogućnosti pristupa fotonaponskoj tehnologiji, kao i zakonskih okvira. U središnjem dijelu rada se na primjeru 5 gradova iz karakterističnih regija u RH analizirala isplativost ulaganja u 5 kW i 10 kW on-grid fotonaponske sustave u vidu vremena potrebnog za povrat investicije u odnosu na alternativu - kupnju električne energije od opskrbljivača. Analiza se izvršila pomoću softwarea PVGIS-a na temelju godišnjih podataka o prosječnom zračenju Sunca i proizvodnji električne energije iz zadanih sustava. Uz to je proračunat i jedinični trošak proizvedene električne energije iz fotonaponskih sustava za odabrane lokacije. Iz svega proizlazi da se za trenutne uvjete u RH, pri kojima je kupovna cijena električne energije viša od prodajne, najviše se isplati ulagati u sustave koji proizvodnjom pokrivaju vlastitu potrošnju električne energije objekta.

Cilj ovog istraživanja bio je ispitati postoji li kod djece razlika u procjeni preferencije druženja s određenim djetetom ovisno o tjelesnoj težini procjenjivanog djeteta. Također, ispitano je hoće li grupa djece od strane ispitanika biti preferirana za druženje onoliko koliko će biti preferiran njen najmanje poželjan član, a ne kao suma iskazanih preferencija prema svakom članu grupe posebno.U istraživanju je sudjelovao prigodni uzorak od 59 dječaka i 43 djevojčice od prvog do četvrtog razreda dviju riječkih osnovnih škola. Zadatak ispitanika bio je procijeniti na skali od 1 do 4 koliko bi se voljeli družiti individualno s djetetom te s grupom djece prikazanima na crtežu. Svako prikazano dijete normalne težine je imalo i svog para blizanca koji je bio pretio, no po svemu ostalome je bio identičan svom paru. Sveukupno je bilo 20 individualnih crteža djece koji su kombinirani u 30 grupa koje su se sastojale od četvero djece različite tjelesne težine i spola. Rezultati su pokazali da ispitanici u značajno većoj mjeri biraju za druženje djecu normalne tjelesne težine u odnosu na pretilu djecu. U grupi koja se sastoji od troje djece normalne težine i jednim pretilim djetetom je veću procjenu poželjnosti druženja imala grupa u situaciji kada su procjene poželjnosti druženja zasnovane na procjeni grupe kao cjeline od grupe u situaciji kada su procjene poželjnosti druženja zasnovane na sumi individualnih preferencija za druženje sa svakim članom grupe. Prema hipotezi je očekivano da će veću procjenu poželjnosti druženja imati grupa čije su procjene zasnovane na sumi individualnih preferencija za druženje sa svakim članom grupe jer će u grupi koja je procijenjena kao cjelina pretilo dijete zbog salijentnosti i efekta neposredne blizine utjecati na smanjenje procjene poželjnosti druženja s tom grupom, što ovim istraživanjem nije dobiveno.Navedeni rezultati pružaju osnovu za provedbu daljnjih istraživanja kojima bi se dodatno ispitao efekt neposredne blizine u kontekstu poželjnosti druženja s grupama djece u kojima se zajedno nalaze djeca normalne tjelesne težine i pretila djeca. Također, rezultati ovog istraživanja ukazuju na važnost kontakta kao efikasnog načina smanjenja predrasuda prema pretiloj djeci., The aim of this paper was to explore if there is a difference in children's estimates of socializing preference with children of different body weight. Also, we tested if the group of children selected for socializing would be as preferred as its least preferred member or if the groups preference would be a sum of the individual member preferences.The study was conducted on a sample of 59 boys and 43 girls from first to fourth grade who attend two elementary schools in Rijeka. Participants had to rate on a scale from 1 to 4 their willingness to socialize with a child or a group of children presented on the picture. Every presented average-weight child also had its obese twin pair who was in every way identical to its twin, except in weight. A total of 20 individual pictures of children were combined in 30 qualitatively different groups of four children. The results showed that participants significantly preferred socializing with average-weight children than with obese children. The group which consisted of three average weight children and one obese child had a higher socializing preference when the preference ratings were given to group as a whole rather than when the ratings were calculated as the sum of each individual group member socializing preference. According to our hypothesis, we expected that the group whose preference ratings were calculated as the sum of each individual group member preference for socializing would have higher preference ratings than the group which was rated as a whole, since the obese child in the latter group would lower the socializing preference of the entire group due to the mere proximity effect. However, the results did not confirm our hypothesis.These findings provide a basis for future researches that would focus on exploring the mere proximity effect in context of socializing preference with groups of children who differ in their body weight. Also, the results emphasize the importance of contact as an effective way of reducing prejudice against obese children.

Analizirani su vremenski nizovi pomoću Takensovog teorema.

This paper investigates the performance and emissions of two stroke low speed marine diesel engines running on alternative fuels such as LNG, methanol, hydrogen, ammonia, and their combinations. The numerical simulation of two stroke low speed ma rine diesel engine performance is based on AVL Boost multi zone combustion model. Calibration and validation of the engine numerical model was performed according to the test results of the actual engine running on marine diesel oil. Simulations were conducted to determine whether the use of alternative fuels can meet the requirements of IMO Tier III regulations for the NOx concentration in exhaust gases. The obtained results show that the use of certain alternative fuels in the operation of two stroke low speed marine engines can reduce NOx and carbon dioxide emissions. All mentioned alternative fuels were optimized to reach the required 3.4 g/kWh of NOx emissions with some gains in power (Methane +7 kW, hydrogen +5 kW) and some loses in power (Diesel + methanol 15 kW, and ammonia + hydrogen 7 kW)