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1. Efficient nanoscale imaging of solid-state phase transitions by transmission electron microscopy demonstrated on vanadium dioxide nanoparticles

Author

Horák, Michal, Kepič, Peter, Kabát, Jiří, Hájek, Martin, Ligmajer, Filip, Konečná, Andrea, Šikola, Tomáš, and Křápek, Vlastimil

Subjects
Condensed Matter - Materials Science
Abstract

We present annular dark field scanning transmission electron microscopy (ADF-STEM) as an efficient, fast, and non-destructive nanoscale tool for monitoring solid-state phase transition. Using metal-insulator transition in vanadium dioxide nanoparticles as an example, we characterize lattice and electronic signatures of the phase transition using analytical transmission electron microscopy including diffraction and electron energy-loss spectroscopy. We demonstrate that ADF-STEM shows a clear contrast across the transition, interpreted with the help of convergent electron beam diffraction as stemming from the crystal-lattice modification accompanying the transition. In addition, ADF-STEM utilizes 3--6 orders of magnitude lower electron dose when compared to electron microscopy techniques able to reveal the phase transition with the same spatial resolution and universality. The benefits of ADF-STEM are emphasized by recording a full hysteresis loop for the metal-insulator transition of a single vanadium dioxide nanoparticle. Our study opens the prospect for fast, non-destructive, large-area and nanoscale characterization of solid-state phase transitions.

Published
2024

22. Comparison of ASIM Traffic Profile Detectors and Floating Car Data During Traffic Incidents

Author

Rapant, Lukáš, Slaninová, Kateřina, Martinovič, Jan, Ščerba, Marek, Hájek, Martin, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Weikum, Gerhard, Series editor, Saeed, Khalid, editor, and Homenda, Wladyslaw, editor

Published
2015
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23. Strength and Structure: Unravelling Lumbar Musculature and Lower Limb Injury Risk in Elite Team Sports

Author

Hajek, Martin and Hajek, Martin

Abstract

Background: Australian Football League (AFL) and National Rugby League (NRL) are elite Australian competitions for rugby league and Australian rules football. Non-contact injuries, like muscle strains and ligament sprains, are very common but the cause of these injuries difficult to identify. There is preliminary evidence in AFL athletes, that reduced cross-sectional area of the lumbar multifidus at the fifth vertebrae and increased cross-sectional area of the quadratus lumborum measured via ultrasound imaging, is a risk factor for sustaining any non-contact lower limb injuries. The lumbar multifidus and quadratus lumborum are both involved in trunk extension, rotation, and proprioception and believed to influence hip and trunk kinematics during exercise. However, there is limited evidence showing a mechanistic link between lumbar muscle cross-sectional area and pooled noncontact lower limb injuries. Assessing the force generating capacity of lumbar spine muscles may provide a better understanding to why the lumbar multifidus at the fifth lumbar vertebral level and quadratus lumborum are potential risk factors for lower limb injuries. Previous studies have only assessed lumbar muscle morphology in single sport cohorts (Australian rules football) that mainly consisted of small sample sizes. With most the literature reporting the same sport, there are uncertainties about the applicability in other sports. This thesis aims to (1) develop a novel trunk and hip extensor strength test and assess its reliability, (2) replicate a previously established model to assess non-contact lower limb injury risk in elite team sports based on lumbar muscle morphology, (3) develop a predictive model for hamstring strain and knee ligament injury risk based on lumbar muscle morphology and strength, and (4) systematically review and meta analyse the literature on lumbar muscle characteristics as a risk factor for non-contact lower limb injuries. [...], Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Health Sci & Soc Wrk, Griffith Health, Full Text

Published
2023

24. viaRODOS: Monitoring and Visualisation of Current Traffic Situation on Highways

Author

Fedorčák, Dušan, Kocyan, Tomáš, Hájek, Martin, Szturcová, Daniela, Martinovič, Jan, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Kobsa, Alfred, Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Weikum, Gerhard, Series editor, Saeed, Khalid, editor, and Snášel, Václav, editor

Published
2014
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30. Predicting Noncontact Lower Limb Injury Using Lumbar Morphology in Professional Australian Football and Rugby League Players

Author

Hajek, Martin, Williams, Morgan D., Bourne, Matthew N., Roberts, Llion A., Morris, Norman R., Shield, Anthony J., Mingin, Cassandra V., Headrick, Jonathon, Duhig, Steven J., Hajek, Martin, Williams, Morgan D., Bourne, Matthew N., Roberts, Llion A., Morris, Norman R., Shield, Anthony J., Mingin, Cassandra V., Headrick, Jonathon, and Duhig, Steven J.

Abstract

Introduction: Noncontact lower limb injuries are common within the Australian Football League (AFL) and National Rugby League (NRL). Smaller (<8.5 cm2) lumbar multifidus at the fifth vertebra (LM L5) and larger (>8.2 cm2) quadratus lumborum (QL) cross-sectional area (CSA) have been associated with increased noncontact lower limb injury risk in AFL players. These associations have not been explored in an NRL cohort. This study will attempt to replicate previous research findings by confirming that muscle morphology is associated with noncontact lower limb injury. Methods: AFL (n = 87) and NRL (n = 151) players underwent LM L2–L5 and QL CSA ultrasound measures during preseason. Each club’s medical staff reported all noncontact lower limb injuries sustained in the subsequent regular season. LM and QL CSA, age, body mass index, and noncontact lower limb injuries were analyzed using multivariable logistic regression. Results: Seventy-two players sustained a noncontact lower limb injury in the 2020 regular season (AFL = 21, NRL = 51). The multivariable logistic regression (odds ratio (OR) = 1.36; 95% confidence interval (CI), 1.02–1.85; P = 0.038) identified AFL players with larger QL CSA at increased risk of sustaining a noncontact lower limb injury during the regular season, but no relationship was found for LM CSA and noncontact lower limb injuries in the AFL (OR = 1.01; 95% CI, 0.36–2.78; P = 0.591) or NRL (OR = 0.63; 95% CI, 0.29–1.33; P = 0.149). Conclusions: AFL players who sustained regular season noncontact lower limb injuries had larger QL CSA in preseason tests. No significant associations between either LM L5 CSA or LM L5 to QL ratio and regular season noncontact lower limb injuries were found.

Published
2022

38. Out of Arabia--the settlement of Island Soqotra as revealed by mitochondrial and Y chromosome genetic diversity

Author

Cerny, Viktor, Pereira, Luisa, Kujanova, Martina, Vasikova, Alzbeta, Hajek, Martin, Morris, Miranda, and Mulligan, Connie J.

Subjects
Biological diversity -- Analysis, Mitochondrial DNA -- Analysis, Anthropology/archeology/folklore
Abstract

The Soqotra archipelago is one of the most isolated landmasses in the world, situated at the mouth of the Gulf of Aden between the Horn of Africa and southern Arabia. The main island of Soqotra lies not far from the proposed southern migration route of anatomically modern humans out of Africa ~60,000 years ago (kya), suggesting the island may harbor traces of that first dispersal. Nothing is known about the timing and origin of the first Soqotri settlers. The oldest historical visitors to the island in the 15th century reported only the presence of an ancient population. We collected samples throughout the island and analyzed mitochondrial DNA and Y-chromosomal variation. We found little African influence among the indigenous people of the island. Although the island population likely experienced founder effects, links to the Arabian Peninsula or southwestern Asia can still be found. In comparison with datasets from neighboring regions, the Soqotri population shows evidence of long-term isolation and autochthonous evolution of several mitochondrial haplogroups. Specifically, we identified two high-frequency founder lineages that have not been detected in any other populations and classified them as a new R0a1a1 subclade. Recent expansion of the novel lineages is consistent with a Holocene settlement of the island ~6 kya. KEY WORDS mtDNA and NRY diversity; regional sampling; phylogeography; migrations; Southern Arabia

Published
2009

39. Regional differences in the distribution of the sub-Saharan, west Eurasian, and South Asian mtDNA lineages in Yemen

Author

Cerny, Viktor, Mulligan, Connie J., Ridl, Jakub, Zaloudkova, Martina, Edens, Christopher M., Hajek, Martin, and Pereira, Luisa

Subjects
Mitochondrial DNA -- Properties, Phylogeny -- Research, Geography -- Research, Yemenites -- Genetic aspects, Population biology -- Genetic aspects, Anthropology/archeology/folklore
Abstract

Despite its key location for population movements out of and back into Africa, Yemen has not yet been sampled on a regional level for an investigation of sub-Saharan, West Eurasian, and South Asian genetic contributions. In this study, we present mitochondrial DNA (mtDNA) data for regionally distinct Yemeni populations that reveal different distributions of mtDNA lineages. An extensive database of mtDNA sequences from North and East African, Middle Eastern and Indian populations was analyzed to provide a context for the regional Yemeni mtDNA datasets. The groups of western Yemen appear to be most closely related to Middle Eastern and North African populations, while the eastern Yemeni population from Hadramawt is most closely related to East Africa. Furthermore, haplotype matches with Africa are almost exclusively confined to West Eurasian ROa haplogroup in southwestern Yemen, although more sub-Saharan L-type matches appear in more northern Yemeni populations. In fact, Yemeni populations have the highest frequency of ROa haplotypes detected to date, thus Yemen or southern Arabia may be the site of the initial expansion of this haplogroup. Whereas two variants of the sub-Saharan haplogroup M1 were detected only in southwestern Yemen close to the Bab elMandeb Strait, different non-African M haplotypes were detected at low frequencies (~2%) in western parts of the country and at a higher frequency (7.5%) in the Hadramawt. We conclude that the Yemeni gene pool is highly stratified both regionally and temporally and that it has received West Eurasian, Northeast African, and South Asian gene flow. KEY WORDS mtDNA diversity; regional sampling; population distances; phylogeography

Published
2008

40. Die Auswirkungen von IoT auf den Versicherungsvertrieb anhand des Risikofeldes: 'Personalisierte Polizze'

Author

Hajek, Martin

Subjects
Digitalisierung, internet of things (IoT), Versicherungswirtschaft, digitization, Produkt, Internet der Dinge, impact on insurance sales, Einfluss Vertrieb von Versicherungsprodukten
Abstract

Die vorliegende Masterarbeit untersucht das Internet of Things(IoT) im Versicherungsbereich und dessen Einfluss auf den Vertrieb von Versicherungsprodukten. Im Rahmen dieser Arbeit wird die Frage gestellt, welcher Bedarf bei KonsumentInnen in Bezug auf die Personalisierung von Versicherungspolizzen in den Sparten Schaden-, Vermögen-und Personenversicherung unter besonderer Berücksichtigung soziodemographischer Variablen festgestellt werden kann und inwiefern Implikationen für den Versicherungsvertrieb ableitbar sind. Untersucht wurde die Fragestellung an n=125 ProbandInnen mittels quantitativer Fragebogenstudie. Der Fragebogen umfasste sowohl die Abfrage soziodemographischer Merkmale sowie die Eruierung des KundInnenbedarfs an diversen Versicherungsprodukten generell. Darüber hinaus wurden Items zum IoT und dessen Anwendung im täglichen Leben erstellt und abgefragt, ob gewisse IoT basierte Versicherungsprodukte von den ProbandInnen abgeschlossen werden würden. Die Ergebnisse zeigen, dass sich das IoT im Versicherungswesen aktuell nur vereinzelt einer hohen KundInnenakzeptanz gegenübersieht. Die wesentlichen Probleme basieren einerseits auf dem fehlenden Vertrauen und andererseits auf dem hohen Informationsbedarf der KundInnen. Zudem konnten im Rahmen einer Clusteranalyse 3 Kundengruppen definiert werden, die sich im Wesentlichen durch ihre Einstellung gegenüber dem IoT differenzieren (Cluster1=Ablehnung, Cluster 2=indifferent, Cluster3=Zustimmung).Es zeigt sich, dass das KundInnenvertrauen ein zentrales Element ist, damit IoT erfolgreich im Versicherungsbereich implementiert werden kann.Um diese Herausforderung zu bewältigen, bietet es sich grundsätzlich an, den/die VersicherungsvermittlerIn künftig als vertrauensstiftende Einheit hervorzuheben und das IoT bzw. die Digitalisierung mithilfe des Vertriebs anzukurbeln. This thesis examines the role of “Internet of Things” (IOT) in the insurance sector and its impact on insurance sales. In this context, the central research question addresses what consumer requirements for the personalization of insurance policies in the categories of property and personal insurance, can be determined with special consideration of soci-odemographic variables and to what extent implications for insurance sales can be measured. The question was examined on n=125 subjects by means of a quantitative questionnaire study. The questionnaire comprised of questions regarding sociodemographic characteristics and the determination of customer needs for various insurance products in general. Additionally, items were created on the IoT and their application in daily routine and whether certain IoT-based insurance products would be chosen by the participants, was evaluated. The results show that the IoT in the insurance sector is currently facing a high level of customer acceptance in isolated cases. The main issues are on the one hand on the lack of trust, and on the other hand on the high demand for information from customers. In addition, as part of a cluster analysis, it was possible to define 3 customer groups, which essentially differ in their attitude towards the IoT (cluster 1 = rejection, cluster 2 = indif-ferent, cluster 3 = approval).Results show that, customer trust is a central element so that IoT can be successfully implemented in the insurance sector. In order to mitigate this challenge, it is generally advisable to integrate the insurance broker as a trust-building party in the future and to stimulate the IoT and digitization with his or her help. eingereicht von: Martin Hajek Masterarbeit FH JOANNEUM 2020

Published
2020

42. Olomoučtí Němci 1918–1938

Author

Hájek Martin and Hájek Martin

Subjects
Germans--History--20th century.--Czech Repub, Germans--Social conditions.--Czech Republic --, Germans--Political activity--Czech Republic --
Abstract

The book deals with selected aspects of the German minority in Olomouc between 1918 and 1938. It also deals with the demographic situation in the city with a special focus on national relations. The main part of the book is devoted to the Germans and Czech-German relations in municipal politics. In this part, the chronological development of municipal politics is monitored. The biographies of the various actors of German politics are briefly described. The club life is presented on the example of several German clubs. The book also presents German-language public press. Furthermore, it describes conflicts in education, development of German education system, school administration and system of German schools in the city. The activities of the German Public Library are briefly introduced.

Published
2020

43. Analysis of potential applications and business models for battery energy storage systems on a low and medium voltage distribution systems in Brazil

Author

Hajek, Martin, Impinnisi, Patrício Rodolfo, Schweiger, Hans-Georg, Universidade Federal do Paraná. Setor de Tecnologia. Programa de Pós-Graduação em Engenharia Elétrica, and Aoki, Alexandre Rasi

Subjects
Baterias elétricas, Energia eletrica - Conservação, Reguladores de voltagem, Teses, Engenharia elétrica
Abstract

Orientador : Prof. Dr. Alexandre Rasi Aoki Coorientadores : Prof. Dr. Patricio Rodolfo Impinnisi ; Prof. Dr. Hans-Georg Schweiger Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia Elétrica. Defesa: Curitiba, 22/05/2017 Inclui referências : p. 221-227 Resumo: A escassez de recursos, o aquecimento global e os desastres naturais aumentaram a conscientização ambiental e desencadearam notáveis esforços de transformação em todo o mundo, afastando da geração baseada em fontes fósseis para a geração de recursos energéticos renováveis na última década. A tendência global de Sistemas de Armazenamento de Energia Elétrica, especialmente as baterias, é uma promissora solução para a qualidade e segurança dos futuros sistemas de redes elétricas inteligentes com uma elevada quota de produção de energia renovável. A aplicabilidade e o desempenho técnico e econômico dos sistemas de baterias distribuídas dependem fortemente de múltiplas questões, que incluem a localização do projeto, o ambiente, as regulamentações do mercado da eletricidade, a aplicação, a tecnologia, a propriedade e o regime de remuneração. Desta forma, o conhecimento e as melhores práticas para a utilização da bateria distribuída, desenvolvidos em diferentes ambientes, não podem ser aplicados diretamente no cenário nacional, mas as circunstâncias e necessidades locais precisam ser estudadas e soluções adequadas e customizadas identificadas. Alinhada com os esforços mundiais em P&D para melhorar o desempenho técnico-econômico das tecnologias de baterias, a última solicitação pública de projetos estratégicos de P&D da Agência Nacional de Energia Elétrica (ANEEL) tem como objetivo identificar aplicações razoáveis e modelos de negócios para sistemas distribuídos de armazenamento de energia no Brasil. O objetivo deste trabalho é desenvolver um método para identificar como os sistemas distribuídos de baterias podem ser usados para melhorar a qualidade das redes de eletricidade renovável a nível nacional. Para isso, foi realizada uma pesquisa bibliográfica sobre os fundamentos das tecnologias e aplicações de baterias, seguida de uma coleta de dados sobre o estado da arte em P&D para sistemas de baterias distribuídas. O mercado brasileiro de eletricidade é estudado em termos de estrutura geral, partindo da participação e regulamentação relevante para geração distribuída e aplicação de armazenamento. Apresenta-se uma visão geral de todos os dados relevantes e do processo desenvolvido e detalhado, para identificar modelos de negócios apropriados para aplicação de bateria distribuída. Com base no resultado do último convite à apresentação de propostas do projeto estratégico de pesquisa e desenvolvimento, denominado Chamada 21, é criado um modelo para sistemas de armazenamento distribuído no Brasil para os próximos quatro anos, incluindo uma classificação das seis principais classificações de tipos e aplicações de baterias. A funcionalidade do método desenvolvido é comprovada pela identificação de um projeto exemplo de utilização distribuída do sistema de bateria para cada uma das classificações identificadas a partir do modelo brasileiro. Sob condições atuais de mercado e meio ambiente, esses projetos são simulados em termos de desempenho técnico-econômico com o programa de simulação de redes elétricas inteligentes no Homer Energy. Os resultados de custo e desempenho são comparados com soluções convencionais, para identificar a adequação de sistemas de baterias distribuídas e potenciais nichos de mercado. Em termos de eletrificações isoladas de fora da rede, em pequena escala, já foram identificados custos de operação global vantajosos. O método e o programa de simulação utilizado revelaram-se ferramentas razoáveis para identificar modelos de negócios para aplicações de bateria distribuída no Brasil e calcular as estruturas de cálculo de custos esperadas. Palavras-chave: Bateria, Modelo de Negócio, Baixa Tensão, Media Tensão, Brasil, Armazenamento de Energia Elétrica Abstract: Resource scarcity, global warming and environmental disasters increased environmental awareness and unleashed remarkable worldwide transformation efforts away from fossil to renewable energy resources based generation during the last decade. There is a global trend for Electrical Energy Storage Systems (ESS) and especially batteries are one of the promising solutions for quality and safety in future, smart electricity networks with high shares of fluctuating renewable energy generation. Applicability and technical economic performance of distributed battery systems are strongly dependent on multiple issues, which include the project location, environment, electricity market regulations, application, technology, ownership and remuneration scheme. This way, knowledge and best practice for distributed battery utilization, developed in different environments, cannot be transferred directly to the national case, but local circumstances and needs have to be studied and appropriate, customized solutions identified. Aligned with the worldwide efforts on R&D to improve techno-economic performance of battery technologies, the latest public call for strategic R&D projects from the Brazilian Electricity Regulatory Agency - ANEEL, aims to identify reasonable applications and business models for distributed energy storage systems in Brazil. Objective of this work is to develop a method to identify how distributed battery systems can be used to improve the quality of renewable electricity networks on a nationalized level. To reach this, a literature research on the fundaments of battery technologies and applications, followed by a data collection on the state of the art in R&D for distributed battery systems are executed. The Brazilian electricity market is studied in terms of general structure, participation parties and relevant regulatory for distributed generation and storage application. An overview of all relevant data and the developed, detailed process, to identify appropriate business models for distributed battery application are presented. Based on the outcome of the last Public call for proposals from the strategic R&D project, known as Chamada 21, a roadmap for distributed storage systems in Brazil for the next four years is created, including a classification in six main classifications of battery types and applications. The functionality of the developed method is proved by identification of one exemplary project of distributed battery system utilization for each of the identified classifications from the Brazilian road map. Under current market and environment conditions, these projects are further simulated in terms of techno economic performance with the smart grid simulation program Homer Energy. The results of cost and performance are compared with conventional solutions, to identify the suitability of distributed battery systems and potential market niches. In terms of small scale, isolated off-grid electrifications there have been already advantageous overall operation cost identified. The method as well as the utilized simulation program turned out to be reasonable tools to identify business models for distributed battery applications in Brazil and calculate the expected costing structures. Keywords: Battery Energy Storage. Business Case. Low Voltage. Medium Voltage. Brazil. Electricity Storage.

Published
2017

46. Mitochondrial DNA and craniofacial covariability of Chad Basin females indicate past population events

Author

Hajek, Martin, Cerny, Viktor, and Bruzek, Jaroslav

Subjects
Chad -- Health aspects, Craniofacial abnormalities -- Analysis, Mitochondrial DNA -- Research, Population genetics -- Analysis, Biological sciences
Abstract

Several analyses are conducted to explain the relationships between the physical features and mitochondrial DNA and craniofacial covariability of Chad Basin females. The co-variance is shown to indicate past population events that made facial differentiation possible.

Published
2008

47. Application of a Cumulative Method for Car Borders Specification in Image

Author

Dobrovolny, Martin, Bezousek, Pavel, and Hajek, Martin

Subjects
edge detection, Image processing, car detection, lcsh:Electrical engineering. Electronics. Nuclear engineering, Intelligent Driver Systems (IDS), cumulative method, lcsh:TK1-9971
Abstract

The paper deals with low-level car detection methods in images. The car detection is an integral part of all intelligent car cruise systems. This article describes the method for suppression of the edges produced by classical edge\'s operators, based on application of the cumulative method. The designed method uses the non-stationary property of the picture background in time-realizations of the image signal.

Published
2008

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