Advanced direct metal 3D printed passive components for wireless communications and satellite applications

This thesis presents the design of advanced microwave passive filters, antennas, and antenna arrays using direct metal 3D printing technology. These work all incorporate the printing technology into the RF component design process, demonstrating the potential possibilities of direct metal 3D printing in the investigation and fabrication of passive microwave components with irregular shapes but attractive features. This thesis's works involved an extensive frequency range that starts with investigating S-band filters and then extends to C-band and Ku-band filters and antennas design. It is well known that in S- and C- band radio frequency (RF) applications that miniaturization is a critical factor for RF devices besides high performances. For this reason, the first project in this thesis proposed a novel compact waveguide loaded air slots resonator for designing inline bandpass filters. As a result, the designed filters not only have a smaller size than coaxial ones but also have controllable transmission zeros with inline structures. Since the air slots resonator is loaded inside the cavity, it is difficult to fabricate by conventional methods, but accessible by 3D printing technique with appropriate self-support structures. The fabrication quality was reflected by the mechanical and RF property measurements, which first demonstrated the advantage of using 3D printing technique to fabricate components with complex structures. The second project presents a compact high-Q fan-shaped folded waveguide resonator, which is applied to successfully design one C-band filter and filtering antenna. High performance RF properties and easy-to-print structures are always considered together. Accordingly, this work proposed and validated novel slots cross negative coupling topology of the filter and novel filtering antenna theory. Also, each of the designed components has better self-supported structures that can be printed with only two pieces, which highly reduced assembly processes and errors. Furthermore, the RF properties from measurement results further demonstrated that the reliability of the metal 3D printing technology for C-band RF applications. The concepts of the third project are extended from the second project but replaces the folded waveguide resonator with a metal strong coupling resonator (MSCR). The MSCR allows for even further compact dimensions while maintaining a high Q value of over 1000. It also allows producing mixed electrical-magnetic coupling by the curving coupling metal pairs intentionally. Except for the desired RF properties, the designed filter based on the MSCR can be printed as a whole even with complex inner circuits structures. Furthermore, the MSCR was integrated with the helical antenna using the proposed theory presented in the second project. Although the helical antenna belongs to the electrical-small antenna, the designed filtering antenna still has a high transmission efficiency of more than 95% and a 6 dBi realized gain concerning its less than quarter-wavelength. In addition, the filtering antenna has five helical radiation elements and one filter prototype but was printed with only three pieces, which showed the advantages of the direct metal 3D printing technology again. The fourth and the last project introduces a Ku-band slots antenna array application based on the sine corrugated waveguide resonator. Similar to previous projects, advanced RF performances were pursued in this project, in addition to demonstrating the use of 3D printing technology to fabricate compact and specific structures. The designed antenna array achieved a higher gain, wider band, and more simple feeding networks. The mode analysis method based on the EM software CST was applied to guide the design since no related formulas were available. The designed model was printed with two pieces and was measured thoroughly. The measured surface roughness, in-band responses, and radiation patterns showed promising results for the sine corrugated waveguide and 3D printing technology in satellite applications. In general, this thesis researched and proved the reliability and advantages of direct metal 3D printing technology in designing and fabricating advanced microwave passive components below the Ku-band. It should be mentioned that the designed passive components in this thesis can be easily re-designed/re-configured and applied on the 5G wireless base station and satellite communication systems

Postawy szlachty polskiej z terenów II zaboru pruskiego wobec władz pruskich z 1793 r.

Wczesną wiosną 1793 r. praktycznie bez walki Prusy przejęły większość ziem przypadłych im w wyniku II rozbioru1. Konfederacja targowicka nie zdobyła się na ostrzejsze wystąpienie w ich obronie1 2. Dywizja Arnolda Byszewskiego, stacjonująca w Wielkopolsce, mimo iż miała realne szanse przeciwstawić się armii pruskiej, nie otrzymała takiego rozkazu od konfederacji generalnej3[…

Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019

Background: In an era of shifting global agendas and expanded emphasis on non-communicable diseases and injuries along with communicable diseases, sound evidence on trends by cause at the national level is essential. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) provides a systematic scientific assessment of published, publicly available, and contributed data on incidence, prevalence, and mortality for a mutually exclusive and collectively exhaustive list of diseases and injuries. Methods: GBD estimates incidence, prevalence, mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) due to 369 diseases and injuries, for two sexes, and for 204 countries and territories. Input data were extracted from censuses, household surveys, civil registration and vital statistics, disease registries, health service use, air pollution monitors, satellite imaging, disease notifications, and other sources. Cause-specific death rates and cause fractions were calculated using the Cause of Death Ensemble model and spatiotemporal Gaussian process regression. Cause-specific deaths were adjusted to match the total all-cause deaths calculated as part of the GBD population, fertility, and mortality estimates. Deaths were multiplied by standard life expectancy at each age to calculate YLLs. A Bayesian meta-regression modelling tool, DisMod-MR 2.1, was used to ensure consistency between incidence, prevalence, remission, excess mortality, and cause-specific mortality for most causes. Prevalence estimates were multiplied by disability weights for mutually exclusive sequelae of diseases and injuries to calculate YLDs. We considered results in the context of the Socio-demographic Index (SDI), a composite indicator of income per capita, years of schooling, and fertility rate in females younger than 25 years. Uncertainty intervals (UIs) were generated for every metric using the 25th and 975th ordered 1000 draw values of the posterior distribution. Findings: Global health has steadily improved over the past 30 years as measured by age-standardised DALY rates. After taking into account population growth and ageing, the absolute number of DALYs has remained stable. Since 2010, the pace of decline in global age-standardised DALY rates has accelerated in age groups younger than 50 years compared with the 1990–2010 time period, with the greatest annualised rate of decline occurring in the 0–9-year age group. Six infectious diseases were among the top ten causes of DALYs in children younger than 10 years in 2019: lower respiratory infections (ranked second), diarrhoeal diseases (third), malaria (fifth), meningitis (sixth), whooping cough (ninth), and sexually transmitted infections (which, in this age group, is fully accounted for by congenital syphilis; ranked tenth). In adolescents aged 10–24 years, three injury causes were among the top causes of DALYs: road injuries (ranked first), self-harm (third), and interpersonal violence (fifth). Five of the causes that were in the top ten for ages 10–24 years were also in the top ten in the 25–49-year age group: road injuries (ranked first), HIV/AIDS (second), low back pain (fourth), headache disorders (fifth), and depressive disorders (sixth). In 2019, ischaemic heart disease and stroke were the top-ranked causes of DALYs in both the 50–74-year and 75-years-and-older age groups. Since 1990, there has been a marked shift towards a greater proportion of burden due to YLDs from non-communicable diseases and injuries. In 2019, there were 11 countries where non-communicable disease and injury YLDs constituted more than half of all disease burden. Decreases in age-standardised DALY rates have accelerated over the past decade in countries at the lower end of the SDI range, while improvements have started to stagnate or even reverse in countries with higher SDI. Interpretation: As disability becomes an increasingly large component of disease burden and a larger component of health expenditure, greater research and developm nt investment is needed to identify new, more effective intervention strategies. With a rapidly ageing global population, the demands on health services to deal with disabling outcomes, which increase with age, will require policy makers to anticipate these changes. The mix of universal and more geographically specific influences on health reinforces the need for regular reporting on population health in detail and by underlying cause to help decision makers to identify success stories of disease control to emulate, as well as opportunities to improve. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens