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Analýza přínosů projektů OHK Brno pro podnikatele v regionu / Analysis of project OHK Brno for business subject in regionMajer, Petr January 2008 (has links)
This thesis seeks to analyze the impact of a range of projects of Chamber of Commerce Brno on the entrepreneurs from the respective region. The thesis describes the structure and the overall operation of the Chamber of Commerce Brno as well as its several projects. In order to evaluate, there are three marketing researches that need to be taken into a consideration. Those marketing researches had been realised during the period of 2005 – 2007. Baring the results risen from the abovementioned marketing researchs in mind, the created situation has been assessed, and based on the personal experience the recommendations dedicated to the management have been created.
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Statická analýza spoje dřevěné konstrukce / Static analysis of one joint of timber structureSedlák, Petr January 2015 (has links)
This diploma thesis deals with the numerical modeling of the nail joint of the timber roof structure and it is based on the already realized physical experiment. Totally twelve various solutions, where the isotropic and ortotropic characteristics of the spruce timber and steel components change, have been created. The final values of the joint shift obtained by using of the numerical modeling are compared with results of physical experiment. Program system ANSYS is used.
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Analýza a optimalizace selektivních technologických procesů pro kontakty krystalických křemíkových solárních článků / The Analysis and Optimization of Selective Technological Processes for Contacts on Crystalline Silicon Solar CellsHladík, Jiří January 2013 (has links)
The submitted work deals with the methods for manufacturing and analysis of contacts on crystalline silicon solar cells. It is focused on selective processes for the production of solar cells metal contacts. The masking feature of silicon nitride is used for selective silicon etching, selective phosphorus diffusion and selective electro-less nickel deposition. Properties of metal contacts precursors are investigated using optical microscopy and their electrical properties using methods based on a four-point probe method. Results are used for the manufacturing of silicon, solar cell with an innovative type of the structure of the front side metallization: chemical nickel, conductive adhesive and copper wire. This approach allows to reduce shading of the front area of PV cells with the ability to avoid usage of busbars. The another advantage of this approach is in replacement of costly silver in at least 2/3 cross section of the front side metallization. Selective ablation of silicon nitride layer was conducted by means of IR laser beam.
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Bilance elektrodynamických sil působících na kontakt elektrického přístroje. / Electrodynamic forces acting on moving contact of electrical apparatusŠic, Pavel January 2016 (has links)
This master’s thesis is focused on calculation, simulation and experimental verification of electrodynamic forces acting upon movable contact piece of MCCB and experimental current carrying path. A short description of low voltage circuit breakers is briefly discussed in first chapter. Second chapter is focused upon contact system analysis of particular MCCB with thermomagnetic trigger. A hardness of contact materials is briefly described. A detailed analytical calculations were used to determine electrodynamic forces in MCCB. A FEM simulation in ANSYS Maxwell was carried out for comparison with analytical results. An experimental apparatus was designed and built for verification of constriction repulsion force, so called Holm’s force. A series of measurements is subsequently performed on proposed apparatus and results are compared with results from previous chapters.
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Chalcogen modification of GaAs(100) surfaces and metal/GaAs(100) contactsHohenecker, Stefan 03 May 2001 (has links)
Der Einfluss der Modifikation der technologisch relevanten GaAs(100) Oberfläche durch Chalkogene, i.e. Selen, Schwefel und Tellur, wird in dieser Arbeit untersucht. Es wird ein Modell vorgestellt, das die Eigenschaften der modifizierten Oberfläche beschreibt. In einem zweiten Schritt werden die so modifizierten Oberflächen mit Metallen unterschiedlicher Reaktivität und verschiedenen Elektronegativitäten bedampft. Die Bandbreite dieser Eigenschaften wird durch die Metalle Indium und Silber, das Alkalimetall Natrium, das Erdalkalimetall Magnesium und das Halbmetall Antimon abgebildet. Die Untersuchung des Einflusses der Chalkogene auf die chemischen Eigenschaften und die Barrierenhöhe der Metall/GaAs(100) Grenzfläche bilden einen weiteren Schwerpunkt. Die Änderung der Barrierenhöhe wird dabei mit Hilfe des Modells metallinduzierter Bandlückenzustände (metal induced gap states) erklärt. Als experimentelle Techniken werden Photoemissionsspektroskopie, Raman Spektroskopie und Strom-Spannungsmessungen verwendet. / The influence of a modification of the technological relevant GaAs(100) surface by chalcogens, i.e. selenium, sulphur and tellurium, is evaluated in this work. A model is proposed, which describes the properties of the modified surface. In a second step metals of different reactivity and electronegativity have been evaporated onto these modified surfaces. Among these materials were the metals indium and silver, the alkali metal sodium, the earth alkali metal magnesium and the half metal antimony. The investigation of the influence of chalcogens on the chemical properties and the barrier height of the metal/GaAs(100) interface is another point of interest. The change in barrier height is explained by the model of metal induced gap states (MIGS). Photoemission spectroscopy, Raman spectroscopy and current-voltage-measurement have been used as experimental techniques.
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Einfluss intermetallischer Phasen der Systeme Al-Cu und Al-Ag auf den Widerstand stromtragender Verbindungen im Temperaturbereich von 90 °C bis 200 °CPfeifer, Stephanie 26 October 2015 (has links)
Im Netz der Elektroenergieversorgung werden einzelne Netzkomponenten und Betriebsmittel durch Verbindungen elektrisch zusammengeschaltet. Dabei werden häufig Schraubenverbindungen mit Stromschienen eingesetzt. Diese müssen über mehrere Jahrzehnte zuverlässig hohe Ströme tragen können. Abhängig von der sich einstellenden Temperatur an den Verbindungen altern diese mit der Zeit. Die Alterung wird je nach Verbindungssystem von verschiedenen Mechanismen beeinflusst, die alle parallel ablaufen. Bei ruhenden, stationären elektrotechnischen Verbindungen, deren Kontaktpartner aus verschiedenen Materialien bestehen, können abhängig von der Paarung intermetallische Phasen (IMP) entstehen. Die sich bildenden IMP haben schlechtere elektrische und mechanische Eigenschaften als die reinen Metalle. Daraus resultiert ein höherer Verbindungswiderstand. Die erzeugte Verlustleistung sowie die Temperatur der Verbindung steigen an. Dies kann zum Ausfall der Verbindung führen. In der Elektroenergietechnik werden aufgrund ihrer guten elektrischen Leitfähigkeit häufig die Werkstoffe Aluminium und Kupfer sowie das Beschichtungsmetall Silber bei Temperaturen von üblicherweise 90 °C bis 200 °C eingesetzt. Speziell bei Aluminium-Kupfer-Verbindungen, die nicht langzeitstabil sind, wird als maßgebliche Ausfallursache das Bilden von IMP gesehen.
Die IMP des Systems Al-Cu wurden in der Vergangenheit bereits vielfach untersucht. Das Übertragen der Ergebnisse auf die Problematik stromtragender Verbindungen der Elektroenergietechnik ist jedoch nicht ohne Weiteres möglich. Der relevante niedrige Temperaturbereich zwischen 90 °C und 200 °C spielt bei vielen Untersuchungen nur eine untergeordnete Rolle. Zusätzlich können die Eigenschaften der IMP bei unterschiedlichen Herstellungsverfahren voneinander abweichen. Zum System Al-Ag ist in der Literatur nur wenig bekannt. Deshalb wurden für diese Arbeit phasenreine IMP der Systeme Al-Cu und Al-Ag mit unterschiedlichen Herstellungsverfahren bei möglichst identischen Randbedingungen hergestellt. Diese wurden mit einer speziell für diese Proben entwickelten Messeinrichtung elektrisch charakterisiert und der ermittelte spezifische elektrische Widerstand der IMP und ihr Temperaturbeiwert mit Werten aus der Literatur verglichen.
An verschiedenen Schraubenverbindungen mit Stromschienen aus Aluminium und Kupfer wurden Langzeitversuche von bis zu 3 Jahren durchgeführt. Der Verbindungswiderstand wurde abhängig von der Zeit ermittelt. An ausgewählten Verbindungen wurde zusätzlich in zwei identischen Versuchen der Einfluss der Belastung mit Dauer- und Wechsellast auf das Langzeitverhalten untersucht. Mithilfe der an den IMP ermittelten elektrischen Eigenschaf-ten wurde deren Einfluss auf den Verbindungswiderstand berechnet. Die Ergebnisse dieser Modellrechnung wurden mit den Ergebnissen aus den Langzeitversuchen verglichen. Ausgewählte Verbindungen wurden dazu mikroskopisch untersucht. Es wurde festgestellt, dass die IMP nicht ausschließlich das Langzeitverhalten stromtragender Verbindungen bestimmen. Es muss mindestens ein weiterer Alterungsmechanismus einen signifikanten Einfluss haben. Die Untersuchungen deuten darauf hin, dass dabei Sauerstoff eine zentrale Rolle spielen könnte. / In electrical power supply networks a huge number of electrical joints are used to connect transmission lines, conductors, switchgears and other components. During operation these joints are aging due to different aging mechanisms. Depending on the type of the joint several aging mechanisms can take place at the same time. For stationary joints with contact partners made of different materials, the formation of intermetallic compounds (IMC) may be an issue. These IMC have worse electrical and mechanical properties compared to the pure metals. Therefore, the presence of IMC in the contact area results in a higher joint re-sistance and the temperature and the thermal power losses increase. Typical temperatures for high current joints are between 90 °C and 200 °C.
Due to their good electrical conductivity aluminum and copper are often used as conductor materials and silver as a coating material. Especially bimetal joints made of aluminum and copper are not long term stable. The formation of Al-Cu IMC is held responsible as a cause of failure. The IMC of the System Al-Cu have already been studied by several authors. However, it is difficult to apply the results directly to electrical joints in power supply networks. In many studies the low temperature range between 90 °C and 200 °C is not regarded. In addition, the properties of the IMC may vary due to different preparation processes. There is only little information about the system Al-Ag in the literature.
For this work, phase pure IMC of the systems Al-Cu and Al-Ag were prepared by different preparation processes using similar process parameters. These IMC samples were electrically characterized with a specially developed measuring device. The specific electric resistivity and the temperature coefficient of resistance were determined and compared to values taken from the literature. Various combinations of bus bar joints made of aluminum and copper were investigated in long term tests for up to three years. The joint resistance was determined as a function of time.
In addition, for selected joints two identic setups were operated with continuous load and alternating load. The long term behavior was investigated with regard to the load ap-plied. Using the results of the electrical characterization of the IMC their influence on the joint resistance was calculated theoretically. The results of the calculation were compared to the results determined in the long term tests. Selected joints were examined microscopi-cally after termination of the long term tests. It was found, that the long term behavior of bimetal electrical joints with the combination Al-Cu and Al-Ag cannot be exclusively described by the growth of IMC. At least there is one further aging mechanism involved. The studies suggest, that oxygen may have a significant influence.
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Jazyková politika v českých zemích v 18. - 20. století: Škola jako národní politikum / Language Policy in Czech Lands in the 18th-20th century: School as a National Political IssueVelčovský, Václav January 2012 (has links)
No description available.
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Des délits et des hommes : portrait des auteurs d’actions indécentes du Québec et caractéristiques associées à la récidive et à la commission de crimes sexuels avec contactsPaquin-Lafleur, Stéphanie 10 1900 (has links)
Le crime d’action indécente a longtemps été défini par la communauté scientifique et administré par la justice davantage comme une nuisance qu’un crime sexuel. Cette situation peut s’expliquer du fait que ce type de délit n’implique pas de contacts sexuels physiques avec la victime et que les conséquences négatives associées à l’agression sur la victime sont souvent minimisées. Ainsi, cette étude s’inscrit dans le cadre d’un stage à la Division des crimes contre la personne de la Sûreté du Québec. Cette recherche a comme application concrète de soutenir le processus de ciblage des récidivistes potentiels en matière d’actions indécentes dans le cadre de dossiers d’enquêtes. Le but est donc de décrire un portrait rétrospectif de la carrière criminelle des 3 572 auteurs présumés ou avérés d’actions indécentes dénoncés au Québec entre 2011 et 2018
Des analyses univariées, bivariées et multivariées ainsi qu’une courbe ROC ont été effectuées sur la population à l’étude. Les résultats de l’étude suggèrent que près de 22% des infracteurs sont récidivistes en matière d’action indécente et que 18% de la population à l’étude ont commis un crime sexuel avec contacts sur une victime. Les deux groupes se sont également avérés être en grande majorité des hommes, plus jeunes en termes d’âge, plus prolifiques et plus diversifiés en termes de variété de catégories de crimes que ceux qui n’ont jamais récidivé ou commis de crime sexuel avec contact. Finalement, les meilleurs prédicteurs se sont avérés être le sexe des infracteurs, la présence d’antécédents de crimes sexuels, de crimes violents et de crimes de la catégorie « Autres infractions criminelles » pouvant être associés à des bris d’ordonnances ou des omissions de se conformer à des engagements de la Cour. Ces individus demeurent toutefois marginaux puisque la grande majorité de la population d’auteurs d’actions indécentes n’a pas commis de récidive ou encore de crime sexuel avec contact sur une victime. / The crime of indecent act has long been defined by the scientific community and administered by justice more as a nuisance than a sexual crime. This can be explained by the fact that this type of crime does not involve physical sexual contact with the victim and that the negative consequences associated with the assault on the victim are often minimized. Thus, this study is part of an internship at the Crimes Against the Person Division of the Sûreté du Québec. The concrete application of this research is to support the process of targeting potential recidivists for indecent acts in investigation files. The goal is therefore to describe a retrospective portrait of the criminal careers of the 3,572 alleged or proven perpetrators of indecent acts reported in Quebec between 2011 and 2018.
Univariate, bivariate and multivariate analyses and a ROC analysis were performed on the study population. The results of the study suggest that nearly 22% of the offenders are repeat offenders in indecent acts and that 18% of the study population have committed a sexual crime with contact with a victim. Both groups were also found to be overwhelmingly male, younger in terms of age, more prolific, and more diverse in terms of the variety of crime categories than those who had never re-offended or committed a contact sexual crime. Finally, the best predictors were found to be the gender of the offenders, the presence of a history of sexual crimes, violent crimes, and crimes in the "Other Criminal Offences" category that may be associated with breaches of orders or failures to comply with court undertakings. However, these individuals remain marginal since the vast majority of the indecent act offender population has not committed a recidivism or a sexual crime involving contact with a victim.
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Evaluation of dispensed carbon nanotube ink on flexible substrates for biocompatible applicationSchubert, Martin, Berg, Hendrik, Friedrich, Sabine, Bock, Karlheinz 11 February 2019 (has links)
For biomedical electronics the compatibility to the biological environment should be well-considered. Therefore this paper evaluates dispensed carbon nanotubes (CNT's) on polyimide (PI) foil for conductive tracks and electrodes for flexible, biomedical applications. A CNT based ink is investigated regarding biocompatibility, flexibility, conductivity and suitability for electrode materials with contact to artificial body fluids. The testing methods comprise bending tests with resistance monitoring, adhesion tests and the utilization of dynamic fluidic and electrical load on dispensed structures. The CNT ink showed good bending properties up to 2653 cycles with an average sheet resistance of 32.5 Ohm/sq. A demonstration of biocompatibility using the adherent cell line HFFF2 resulted negatively. No delamination or dissolving effects occurred during exposure to 0.9 % sodium chloride solution.
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Sociala skyddsnätets paradox : En kvantitativ studie av välfärdsregimernas inverkan på sociala kontakter och nätverksdiversitet / The Paradox of the Social Safety Net : A Quantitative Study of the Impact of Welfare Regimes on Social connections and Network DiversityKraus, Frida, Gullstrand, Jesper January 2023 (has links)
This study examines the impact welfare regimes might have on the individual’s social network – more specifically, the study investigates the individuals' number of social contacts and the diversity in their social networks. Are there differences in the individual's social network between the different welfare regimes? Does this correlate with the social safety nets provided by the different regimes? The study also aims to compare the strength of this correlation with other variables such as gender, age, educational level, partnership, and employment. This study is based on research theories of social capital, social contacts, and social welfare regimes. The study is quantitative in its nature and uses secondary data from the International Social Survey Program (ISSP) 2017. The method used are two different binary multiple logistic regression models. The first regression model examines the number of social contacts and the second one network diversity. The results indicate that there is a correlation between the number of social contacts, network diversity and welfare regimes. According to this study the stronger the social safety net is, the less diversified the individual’s social network is - and the lower the number of social contacts. This is particularly evident among older individuals in the population. Furthermore, this study suggests that partnership, education,and employment are influential variables for network diversity and the number of social contacts. The study contributes to an understanding on how the social security of welfare regimes tends to reduce individuals' need of creating and maintaining their own social networks. This area, separate from social capital, can contribute to better understanding on how, for example, social isolation can emerge from a macro perspective. However, we recommend further research in this area to provide deeper insight on the effects that may arise.
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