987 resultados para Poles and zeros


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AMS Subject Classification 2010: 11M26, 33C45, 42A38.

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2000 Mathematics Subject Classification: Primary 34C07, secondary 34C08.

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2002 Mathematics Subject Classification: Primary 35В05; Secondary 35L15

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2000 Mathematics Subject Classification: Primary 30C10, 30C15, 31B35.

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MSC 2010: 30C10

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2000 Mathematics Subject Classification: 12D10.

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The Hungarian media shows very contradictory pictures of women today: Successful career women enjoying material well-being is one picture, while the careful mother not working outside the home, keeping together the family is another one. Between these two contradictory poles there are almost no other female actors in the media. Life produces something different. In spite of the fact that there was a big loss of jobs in 1990s, and women’s activity rate decreased while the unemployment rate increased compared to before the 1990s, woman with duel roles are still accepted and common. The first female task is looking after the family and the second one is working outside the home and earning money. In many cases there is a third role: studying in distant or evening courses. In the next chapters we go deeper into this topic. We analyse the different aspects of female labour market positions, and show some relevant characteristics of governmental parental benefits and childcare support, and examine how the new pension system effects women. We also have a quick look at trade unions and show their lack of activity around gender issues. In the labour market analysis of the position of women we use labour force surveys, institution-based labour statistics, and unemployment registers. The Appendix 1 contains short descriptions of these data sources.

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Renewable or sustainable energy (SE) sources have attracted the attention of many countries because the power generated is environmentally friendly, and the sources are not subject to the instability of price and availability. This dissertation presents new trends in the DC-AC converters (inverters) used in renewable energy sources, particularly for photovoltaic (PV) energy systems. A review of the existing technologies is performed for both single-phase and three-phase systems, and the pros and cons of the best candidates are investigated. In many modern energy conversion systems, a DC voltage, which is provided from a SE source or energy storage device, must be boosted and converted to an AC voltage with a fixed amplitude and frequency. A novel switching pattern based on the concept of the conventional space-vector pulse-width-modulated (SVPWM) technique is developed for single-stage, boost-inverters using the topology of current source inverters (CSI). The six main switching states, and two zeros, with three switches conducting at any given instant in conventional SVPWM techniques are modified herein into three charging states and six discharging states with only two switches conducting at any given instant. The charging states are necessary in order to boost the DC input voltage. It is demonstrated that the CSI topology in conjunction with the developed switching pattern is capable of providing the required residential AC voltage from a low DC voltage of one PV panel at its rated power for both linear and nonlinear loads. In a micro-grid, the active and reactive power control and consequently voltage regulation is one of the main requirements. Therefore, the capability of the single-stage boost-inverter in controlling the active power and providing the reactive power is investigated. It is demonstrated that the injected active and reactive power can be independently controlled through two modulation indices introduced in the proposed switching algorithm. The system is capable of injecting a desirable level of reactive power, while the maximum power point tracking (MPPT) dictates the desirable active power. The developed switching pattern is experimentally verified through a laboratory scaled three-phase 200W boost-inverter for both grid-connected and stand-alone cases and the results are presented.

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Sociosexual orientation is a construct describing the propensity to engage in casual sex and sexual activity in uncommitted relationships, varying from restricted to unrestricted orientation. The personality profile of people exhibiting unrestricted sociosexuality matches a personality profile related to eveningness. Previous research on sociosexuality and morningness–eveningness is scarce, however, and conducted only with male participants. The present study aimed at testing whether eveningness is related to unrestricted sociosexuality in both genders. Participants were 352 (62.8% female) Poles aged between 17 and 57. They completed the reduced morningness–eveningness Questionnaire and the revised Sociosexual Orientation Inventory, consisting of three facets: behavior, attitude, and desire. The results revealed that females were more restricted than males in all facets of sociosexuality. Moreover, in both genders older age was related to less restricted behavior and attitude. Analyses showed that morningness– eveningness was unrelated to sociosexuality in males, but in females eveningness was linked to less restricted global sociosexuality .Eveningness in females could be regarded as a contributory factor to the instability of romantic relationships and high-risk sexual behaviors.

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We analyze a real data set pertaining to reindeer fecal pellet-group counts obtained from a survey conducted in a forest area in northern Sweden. In the data set, over 70% of counts are zeros, and there is high spatial correlation. We use conditionally autoregressive random effects for modeling of spatial correlation in a Poisson generalized linear mixed model (GLMM), quasi-Poisson hierarchical generalized linear model (HGLM), zero-inflated Poisson (ZIP), and hurdle models. The quasi-Poisson HGLM allows for both under- and overdispersion with excessive zeros, while the ZIP and hurdle models allow only for overdispersion. In analyzing the real data set, we see that the quasi-Poisson HGLMs can perform better than the other commonly used models, for example, ordinary Poisson HGLMs, spatial ZIP, and spatial hurdle models, and that the underdispersed Poisson HGLMs with spatial correlation fit the reindeer data best. We develop R codes for fitting these models using a unified algorithm for the HGLMs. Spatial count response with an extremely high proportion of zeros, and underdispersion can be successfully modeled using the quasi-Poisson HGLM with spatial random effects.

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We present new methodologies to generate rational function approximations of broadband electromagnetic responses of linear and passive networks of high-speed interconnects, and to construct SPICE-compatible, equivalent circuit representations of the generated rational functions. These new methodologies are driven by the desire to improve the computational efficiency of the rational function fitting process, and to ensure enhanced accuracy of the generated rational function interpolation and its equivalent circuit representation. Toward this goal, we propose two new methodologies for rational function approximation of high-speed interconnect network responses. The first one relies on the use of both time-domain and frequency-domain data, obtained either through measurement or numerical simulation, to generate a rational function representation that extrapolates the input, early-time transient response data to late-time response while at the same time providing a means to both interpolate and extrapolate the used frequency-domain data. The aforementioned hybrid methodology can be considered as a generalization of the frequency-domain rational function fitting utilizing frequency-domain response data only, and the time-domain rational function fitting utilizing transient response data only. In this context, a guideline is proposed for estimating the order of the rational function approximation from transient data. The availability of such an estimate expedites the time-domain rational function fitting process. The second approach relies on the extraction of the delay associated with causal electromagnetic responses of interconnect systems to provide for a more stable rational function process utilizing a lower-order rational function interpolation. A distinctive feature of the proposed methodology is its utilization of scattering parameters. For both methodologies, the approach of fitting the electromagnetic network matrix one element at a time is applied. It is shown that, with regard to the computational cost of the rational function fitting process, such an element-by-element rational function fitting is more advantageous than full matrix fitting for systems with a large number of ports. Despite the disadvantage that different sets of poles are used in the rational function of different elements in the network matrix, such an approach provides for improved accuracy in the fitting of network matrices of systems characterized by both strongly coupled and weakly coupled ports. Finally, in order to provide a means for enforcing passivity in the adopted element-by-element rational function fitting approach, the methodology for passivity enforcement via quadratic programming is modified appropriately for this purpose and demonstrated in the context of element-by-element rational function fitting of the admittance matrix of an electromagnetic multiport.

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The text analyses the intelligence activity against Poland in the period 1944-1989. The paper also contains a case study, i.e. an analysis of the American intelligence service activity held against Poland. While examining the research thesis, the author used the documents and analyses prepared by the Ministry of Internal Affairs. In order to best illustrate the point, the author presented a number of cases of persons who spied for the USA, which was possible thanks to the analysis of the training materials of the Ministry of Internal Affairs directed to the officers of the Security Service and the Citizens’ Militia. The text tackles the following issues: (1) to what extent did the character of the socio-political system influence the number of persons convicted for espionage against Poland in the period under examination?, (2) what was the level of interest of the foreign intelligence services in Poland before the year 1990?, (3) is it possible to indicate the specificity of the U.S. intelligence activity against Poland? 1) The analysis of data indicates that the period 1946-1956 witnessed a great number of convictions for espionage, which is often associated with the peculiar political situation in Poland of that time. Up to 1953, the countries of the Eastern bloc had reproduced the Stalin’s system, which only ceased due to the death of Stalin himself. Since then, the communist systems gradually transformed into the system of nomenklatura. Irrespective of these changes, Poland still witnessed a wave of repressions, which resulted from the threats continuously looming over the communist authorities – combating the anti-communist underground movement, fighting with the Ukrainian Insurgent Army, the Polish government-in-exile, possible revisionism of borders, social discontent related to the socio-political reforms. Hence, a great number of convictions for espionage at that time could be ascribed to purely political sentences. Moreover, equally significant was the fact that the then judicial practice was preoccupied assessing negatively any contacts and relations with foreigners. This excessive number of convictions could ensue from other criminal-law provisions, which applied with respect to the crimes against the State, including espionage. What is also important is the fact that in the Stalin’s period the judiciary personnel acquired their skills and qualifications through intensive courses in law with the predominant spirit of the theory of evidence and law by Andrey Vyshinsky. Additionally, by the decree of 1944 the Penal Code of the Polish Armed Forces was introduced; the code envisaged the increase in the number of offences classified as penalised with death penalty, whereas the high treason was subject to the military jurisdiction (the civilians were prosecuted in military courts till 1955; the espionage, however, still stood under the military jurisdiction). In 1946, there was introduced the Decree on particularly dangerous crimes in the period of the State’s recovery, which was later called a Small Penal Code. 2) The interest that foreign intelligence services expressed in relation to Poland was similar to the one they had in all countries of Eastern and Central Europe. In the case of Poland, it should be noted that foreign intelligence services recruited Polish citizens who had previously stayed abroad and after WWII returned to their home country. The services also gathered information from Poles staying in immigrant camps (e.g. in FRG). The activity of the American intelligence service on the territory of FRG and West Berlin played a key role. The documents of the Ministry of Internal Affairs pointed to the global range of this activity, e.g. through the recruitment of Polish sailors in the ports of the Netherlands, Japan, etc. In line with the development in the 1970s, espionage, which had so far concentrated on the defence and strategic sectors, became focused on science and technology of the People’s Republic of Poland. The acquisition of collaborators in academic circles was much easier, as PRL opened to academic exchange. Due to the system of visas, the process of candidate selection for intelligence services (e.g. the American) began in embassies. In the 1980s, the activity of the foreign intelligence services concentrated on the specific political situation in Poland, i.e. the growing significance of the “Solidarity” social movement. 3) The specificity of the American intelligence activity against Poland was related to the composition of the residency staff, which was the largest in comparison to other Western countries. The wide range of these activities can be proved by the quantitative data of convictions for espionage in the years 1944-1984 (however, one has to bear in mind the factors mentioned earlier in the text, which led to the misinterpretation of these data). Analysing the data and the documents prepared by the Ministry of Internal Affairs, one should treat them with caution, as, frequently, the Polish counter-intelligence service used to classify the ordinary diplomatic practice and any contacts with foreigners as espionage threats. It is clearly visible in the language of the training materials concerned with “secret service methods of the intelligence activity” as well as in the documents on operational activities of the Security Service in relation to foreigners. The level of interest the USA had in Poland was mirrored in the classification of diplomatic posts, according to which Warsaw occupied the second place (the so-called Group “B”) on the three-point scale. The CIA experienced spectacular defeats during their activity in Poland: supporting the Polish underground anti-communist organisation Freedom and Independence and the so-called Munich-Berg episode (both cases took place in the 1950s). The text focuses only on selected issues related to the espionage activities against Poland. Similarly, the analysis of the problem has been based on selected sources, which has limited the research scope - however, it was not the aim of the author to present the espionage activity against Poland in a comprehensive way. In order to assess the real threat posed by the espionage activity, one should analyse the case of persons convicted for espionage in the period 1944-1989, as the available quantitative data, mentioned in the text, cannot constitute an explicit benchmark for the scale of espionage activity. The inaccuracies in the interpretation of data and variables, which can affect the evaluation of this phenomenon, have been pointed out in the text.

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Renewable or sustainable energy (SE) sources have attracted the attention of many countries because the power generated is environmentally friendly, and the sources are not subject to the instability of price and availability. This dissertation presents new trends in the DC-AC converters (inverters) used in renewable energy sources, particularly for photovoltaic (PV) energy systems. A review of the existing technologies is performed for both single-phase and three-phase systems, and the pros and cons of the best candidates are investigated. In many modern energy conversion systems, a DC voltage, which is provided from a SE source or energy storage device, must be boosted and converted to an AC voltage with a fixed amplitude and frequency. A novel switching pattern based on the concept of the conventional space-vector pulse-width-modulated (SVPWM) technique is developed for single-stage, boost-inverters using the topology of current source inverters (CSI). The six main switching states, and two zeros, with three switches conducting at any given instant in conventional SVPWM techniques are modified herein into three charging states and six discharging states with only two switches conducting at any given instant. The charging states are necessary in order to boost the DC input voltage. It is demonstrated that the CSI topology in conjunction with the developed switching pattern is capable of providing the required residential AC voltage from a low DC voltage of one PV panel at its rated power for both linear and nonlinear loads. In a micro-grid, the active and reactive power control and consequently voltage regulation is one of the main requirements. Therefore, the capability of the single-stage boost-inverter in controlling the active power and providing the reactive power is investigated. It is demonstrated that the injected active and reactive power can be independently controlled through two modulation indices introduced in the proposed switching algorithm. The system is capable of injecting a desirable level of reactive power, while the maximum power point tracking (MPPT) dictates the desirable active power. The developed switching pattern is experimentally verified through a laboratory scaled three-phase 200W boost-inverter for both grid-connected and stand-alone cases and the results are presented.

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As the word population continues to grow and global resources are limited, the WHO definition of health is difficult to achieve for a large part of the population. Humanity is facing the need to improve both environmental and human wellbeing. This can be done through careful planning and management of natural resources, ensuring food safety and reducing and converting wastes. This work aims to contribute to the improvement of population and environmental health exploring different research fields: urban park ecosystem services, food chemical risk assessment and agri-food by-product valorization. To highlight the importance of urban parks and their ecosystem services, an ethnobotanical study was carried out in the Ausa urban park in Rimini, using a citizen science approach. The results showed that Ausa Park is an important focal point for plant gatherers in Rimini, as it allows for plant foraging and contributes to preserve the knowledge of the use of plants. Two food safety studies were carried out, looking at the exposure of Poles to bisphenol A through the consumption of soft drinks and to cadmium through the consumption of chocolate bars. The results, compared with EFSA’s scientific opinion, show that the exposure of the Polish population to BPA is of health concern, while cadmium is not. In the agri-food by-product valorization, a green extraction method was optimized to recover valuable phenolic compounds from red-fleshed apple pomace; moreover, the possibility of recovering pectin from the residue was evaluated. Furthermore, valuable compounds in four different types of wheat milling by-products, considered as an alternative source of bioactive compounds with potential human health benefits, were investigated. In conclusion, this work produced usable data in urban green area management and planning, in food chemical risk assessment and in business production decisions, thus contributing to improving environmental and people wellbeing.

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Characterized for the first time in erythrocytes, phosphatidylinositol phosphate kinases (PIP kinases) belong to a family of enzymes that generate various lipid messengers and participate in several cellular processes, including gene expression regulation. Recently, the PIPKIIα gene was found to be differentially expressed in reticulocytes from two siblings with hemoglobin H disease, suggesting a possible relationship between PIPKIIα and the production of globins. Here, we investigated PIPKIIα gene and protein expression and protein localization in hematopoietic-derived cells during their differentiation, and the effects of PIPKIIα silencing on K562 cells. PIPKIIα silencing resulted in an increase in α and γ globins and a decrease in the proliferation of K562 cells without affecting cell cycle progression and apoptosis. In conclusion, using a cell line model, we showed that PIPKIIα is widely expressed in hematopoietic-derived cells, is localized in their cytoplasm and nucleus, and is upregulated during erythroid differentiation. We also showed that PIPKIIα silencing can induce α and γ globin expression and decrease cell proliferation in K562 cells.