Reference Nodes Selection for Anchor-Free Localization in Wireless Sensor Networks

Dizertační práce se zabývá návrhem nového bezkotevního lokalizačního algoritmu sloužícího pro výpočet pozice uzlů v bezdrátových senzorových sítích. Provedené studie ukázaly, že dosavadní bezkotevní lokalizační algoritmy, pracující v paralelním režimu, dosahují malých lokalizačních chyb. Jejich nevýhodou ovšem je, že při sestavení množiny referenčních uzlu spotřebovávají daleko větší množství energie než algoritmy pracující v inkrementálním režimu. Paralelní lokalizační algoritmy využívají pro určení pozice referenční uzly nacházející se na protilehlých hranách bezdrátové sítě. Nový lokalizační algoritmus označený jako BRL (Boundary Recognition aided Localization) je založen na myšlence decentralizovaně detekovat uzly ležící na hranici síti a pouze z této množiny vybrat potřebný počet referenčních uzlu. Pomocí navrženého přístupu lze znažně snížit množství energie spotřebované v průběhu procesu výběru referenčních uzlů v senzorovém poli. Dalším přínosem ke snížení energetických nároku a zároveň zachování nízké lokalizační chyby je využití procesu multilaterace se třemi, eventuálně čtyřmi referenčními body. V rámci práce byly provedeny simulace několika dílčích algoritmu a jejich funkčnost byla ověřena experimentálně v reálné senzorové síti. Navržený algoritmus BRL byl porovnán z hlediska lokalizační chyby a počtu zpracovaných paketů s několika známými lokalizačními algoritmy. Výsledky simulací dokázaly, že navržený algoritmus představuje efektivní řešení pro přesnou a zároveň nízkoenergetickou lokalizaci uzlů v bezdrátových senzorových sítích.The doctoral thesis is focused on a design of a novel anchor free localization algorithm for wireless sensor networks. As introduction, the incremental and concurrent anchor free localization algorithms are presented and their performance is compared. It was found that contemporary anchor free localization algorithms working in the concurrent manner achieve a low localization error, but dissipate signicant energy reserves. A new Boundary Recognition Aided Localization algorithm presented in this thesis is based on an idea to recognize the nodes placed on the boundary of network and thus reduce the number of transmission realized during the reference nodes selection phase of the algorithm. For the position estimation, the algorithm employs the multilateration technique that work eectively with the low number of the reference nodes. Proposed algorithms are tested through the simulations and validated by the real experiment with the wireless sensor network. The novel Boundary Recognition Aided Localization algorithm is compared with the known algorithms in terms of localization error and the communication cost. The results show that the novel algorithm presents powerful solution for the anchor free localization.

Soft skills of Czech graduates

Finding a job is easier for people who are better equipped with soft skills, as they are more productive. Therefore, this article deals with the evaluation of soft skills of graduates from Czech public universities. The results show that the same soft skills are required from university graduates as from the population as a whole (only problem solving is more pronounced with them), but the required level of these skills is 42% higher in the case of graduates. Unfortunately, employers perceive the level of graduates' soft skills insufficient as their level is by 16.46 to 31.15% lower than required. A more detailed analysis showed that, in terms of the development of soft skills, Czech universities provide a very homogenous service. Graduates of universities have nearly the same level of soft skills, while they can also identify similar strengths and weaknesses. These findings suggest that Czech universities should pay more attention to the systematic development of soft skills.Web of Science181604

Određivanje pomaka opterećenoga drvenog stolca primjenom korelacije digitalne slike

The subject of the research is a ready to assemble (RTA) chair constructed of plywood by a CNC machine. The standard test of seat and back of the chair according to the Czech Standard CSN EU 1728 was supplemented with an optical method of digital image correlation (DIC). The aim of the research was to discover mechanical principles of the construction and to develop a methodology of standardized furniture testing. Results of experimental measurement show the response of the chair construction in a form of displacement fields, strain fields, charts and vectors depicting displacement of the observed points. The results can be used to improve mechanical properties of the construction, as well as to develop a shape of the product or specific parts of the product. Besides furniture testing laboratories and research institutes, engineers from development departments of furniture making companies or industrial designers can easily use the presented method.Predmet istraživanja bio je stolac spreman na sklapanje (RTA), izrađen od uslojenog drva na CNC stroju. Standardni test sjedala i naslona stolca prema češkom standardu CSN EU 1728 dopunjen je optičkom metodom korelacije digitalne slike (DIC). Cilj istraživanja bio je otkriti mehanička načela konstrukcije te obogatiti metodologiju standardiziranog ispitivanja namještaja. Rezultati eksperimentalnih mjerenja prikazuju reakciju konstrukcije stolca u obliku polja pomaka, polja naprezanja te grafikona i vektora koji predočuju pomake promatranih točaka. Rezultati se mogu iskoristiti za poboljšanje mehaničkih svojstava konstrukcije, kao i za razvoj oblika proizvoda ili ispitivanih dijelova. Osim u laboratoriju za ispitivanje namještaja ili u istraživačkim institutima, prikazanom se metodom lako mogu koristiti inženjeri razvojnih odjela u tvrtkama za proizvodnju namještaja li industrijski dizajneri

Regional migration in the Czech Republic: Economic factors are the key

This article aims to determine and evaluate factors influencing migration behaviour and decision to migrate in 14 regions of the Czech Republic in the periods 1995–2018 and 2004–2018 (after the accession to the EU). The panel data analysis conducted mostly confirms our hypotheses on the impact of the analysed factors, confirming the impact of GDP growth, number of job listings at Labour Offices, number of job applicants, employment in industry and number of finished dwellings. The exceptions are the variables for the crime rate and number of college students in the region, where we found a positive but barely statistically significant coefficient. One group of factors (GDP growth, jobs at Labour Office, finished dwellings) prove to be pull factors, i.e., they are statistically significant and have a positive impact on migration flows. There are also two push factors, both of which represent the labour market situation and, to some extent, the structure of the economy in the region (number of job applicants and employment in industry). Their relationship with migration flows is negative and statistically significant, while several robustness tests are employed.Web of Science71329026

Prve dvije faze dizajniranja vanjskog namještaja primjenom metode dizajna usmjerene prema korisniku

The article describes a part of the designing process of exterior furniture that utilizes HPL (high pressure laminate) with the reduced use of construction metal elements, using user-centered design methods. The process is divided into several phases. This article primarily uses human-centered design and describes the process of researching user attitudes and market research, as important methods in the overall design process. The observed results are crucial especially when introducing new products based on products already existing on the market. The contemporary market is filled up with a surplus of products that are not so customer-oriented, and customers are often lost in their choice. Currently, there is a tendency on the market to personalize each product to the customer, so this becomes one of the main designer’s methods in designing a product. The designer can personalize a product based on the user and market research. New products can be different in the approach to customer’s needs and attitudes in cases that the designing process follows the current needs. Also, it is important to present it properly to the public. It is necessary to create a representative customer, who can represent the potential group. This young woman has specific characteristics that can be used in the rest of the designing process – her relationship with nature and sitting outdoors, her relationship with furniture and her ability to purchase a new product.U članku se opisuje dio postupka projektiranja vanjskog namještaja za koji se iskorištava HPL (visokotlačni laminat), uz smanjenu upotrebu metalnih građevnih elemenata i uz primjenu metode dizajna usmjerene prema korisniku. Proces je podijeljen na nekoliko faza. U ovom je radu težište na dizajnu podređenom čovjeku, pri čemu se opisuje i postupak istraživanja stajališta korisnika i istraživanje tržišta kao važne metode u cjelokupnom procesu dizajniranja. Uočeni su rezultati presudni za uvođenje novih proizvoda utemeljenih na već postojećim proizvodima na tržištu. Suvremeno je tržište preplavljeno proizvodima koji nisu osobito orijentirani prema kupcu, a kupci se pri izboru često gube u tom mnoštvu ponude. Trenutačno je na tržištu zamjetna težnja da se svaki proizvod prilagodi kupcu, pa to postaje jedno od glavnih dizajnerskih polazišta pri dizajniranju proizvoda. Zahvaljujući istraživanju tržišta i zahtjeva korisnika, dizajner može prilagoditi proizvod svakom pojedinom kupcu. Također, sve je više dokaza da se konkurentnost nekih tvrtki temelji na inovativnoj upotrebi dizajna usmjerenoga prema korisniku. Ako postupak dizajniranja prati trenutačne potrebe i ako se pravilno prezentira u javnosti, novi se proizvodi mogu razlikovati po pristupu potrebama i stajalištima svakog kupca