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International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper presents a history of telemetry at White Sands Missile Range, New Mexico. White Sands Missile Range is located in the Tularosa Basin between the San Andres and the Organ Mountains on the west and the Sacramento Mountains on the east. Designation of more than one million acres of New Mexico range land as a testing areas established White Sands Proving Ground on July 9, 1945 as the Birthplace of Americas Missile and Space activity. On July 16, 1945 the first Atomic Bomb was exploded at Trinity Site. Project Hermes began in November of 1944 with a contract to General Electric by the Ordnance Department to develop a long range guided missile for the Army. Missile testing began in September of 1945 with the firing of Tiny Tim missiles. The capture of German V2 rockets led to testing and firing V2s concurrently with the Hermes. The first two-stage rocket consisted of a WAC Corporal mounted on the nose of a V2. Bumper # 5 set flight records of 5,150 miles an hour and an altitude of 244 miles on February 24, 1949. The paper includes: *Chronological highlights of telemetering events. *Discussion of telemetry systems and events that occurred at WSPG/WSMR from 1944 through 1990. *Telemetry systems and events from 1990 to the present. *Planned future telemetry systems and probable future systems.

This dissertation consists of three essays on econometric analysis including both parametric and nonparametric econometrics. The first chapter outlines three topics involved and briefly discusses the motivations and methods, as well as some conclusions in each of the following chapters. Both chapter 2 and chapter 3 are in the field of kernel smoothed nonparametric econometrics. Chapter 2 conducts large volumes of simulations to explore the properties of various methods proposed in the literature to detect irrelevant variables in a fully nonparametric regression framework. We focus our attention to two broadly sets of methods, the least square cross-validated bandwidth selection procedure and the conventional nonparametric significance testing frameworks. In chapter 3, a bootstrap test statistic is proposed to test the validity of imposing some arbitrary restrictions on higher order derivatives of a regression function. We use data sharpening method to enforce the desired constraints on the shape of the conditional means and then measure the distance between the unrestricted and restricted models. The empirical distribution of the test statistic is generated by bootstrapping and the asymptotic distribution for the bootstrap test statistic is also provided. The last chapter examines the relationship between population health and income inequality in China. We use a multilevel dynamic panel model to test the absolute income hypothesis, various versions of relative income hypothesis, and health selection hypothesis empirically / Ph. D.

In the wake of the Russian invasion of Ukraine, a compelling question arises, could this event have brought Europeans closer? Armed conflicts often strengthen in-group identity as individuals seek safety from external threats. This study speculates that the perceived threat of the invasion might have intensified emotional attachments to Europe across the continent. Additionally, it explores how the response differed between Western Europe and Central and Eastern European countries. This study bases its conceptualization, hypotheses, and interpretations on social identity theory, alongside a comprehensive review of the literature on armed conflict and identity. Utilizing a quasi-experimental method to investigate the probable causal link and using 12 countries from the 10th round of the European Social Survey to generalize the findings across a diverse European population. The findings reveal that Europeans did not develop a stronger sense of European identity in response to the invasion, suggesting that Europeans do not perceive Europe as a meaningful identity to unite under or seek safety in when military conflicts intensify on the continent. This study contributes to the understanding that the European project, along with its socio-political efforts, has been relatively unsuccessful in establishing itself as a significant unifying point when conflicts intensify.

Processing of broadband signals induced on an antenna array using a tapped delay line filter and a set of steering delays has two problems. Firstly one needs to manipulate large matrices to estimate the filter coefficients. Secondly the use of steering delays is not only cumbersome but implementation errors cause loss of system performance. This thesis looks at both of these problems and presents elegant solutions by developing and studying a design method referred to as the DFT method, which does not require steering delays and is computationally less demanding compared to existing methods. Specifically the thesis studies and compares the performance of a time domain element space beamformer using the proposed method and that using an existing method, and develops the DFT method when the processor is implemented in partitioned form. The study presented in the thesis shows that the processors using the DFT method are robust to look direction errors and require less computation than that using the existing method for comparable performance. The thesis further introduces a broadband beamformer design which does not require any steering delays between the sensors and the tapped delay line section as is presently the case. It has the capability of steering the array in an arbitrary direction with a specified frequency response in the look direction while canceling unwanted uncorrelated interferences. The thesis presents and compares the performance of a number of techniques to synthesize an antenna pattern of a broadband array. These techniques are designed to produce isolated point nulls as well as broad sector nulls and to eliminate the need for the steering delays. Two of the pattern synthesis techniques presented in the thesis allow optimization against unwanted interferences in unknown directions. The techniques allow formulation of a beamforming problem such that the processor is not only able to place nulls in specified directions but also able to cancel directional interferences in unknown directions along with a specified frequency response in the look direction over a band of interest. The thesis also presents a set of directional constraints such that one does not need steering delays and an array can be constrained in an arbitrary direction with a specified frequency response. The constraints presented in the thesis are simple to implement. Based on these constraints a pattern synthesis technique for broadband antenna array is also presented.

The recent growth in the ambit of modern wireless communication and in particular WLAN (Wireless Local Area Network) systems has created a niche for novel designs that have the capacity to send and/or receive arbitrary orthogonal polarizations. The designs should also be able to support dual-band functionality, while maintaining a compact structure. The first aim of this dissertation was thus to develop a dual-band single radiating element that can cover the 2.4 GHz (2.4 – 2.484 GHz) band and the 5.2 GHz (5.15 – 5.85 GHz) band for the IEEE 802.11b and IEEE 802.11a WLAN standards respectively. Dual-frequency elements such as stacked-, notched- and dichroic patches have been considered, but due to the size and the high cross-polarization levels associated with these designs, the design process was propelled towards various dipole and monopole configurations. The attributes of various designs were compared, where the double Rhombus antenna pregnant with dual-band and dual-polarization potential was used as basis in the development of the DBDP (Dual-Band Dual-Polarized) antenna design. The single-element design exhibited wide bandwidths, good end-fire radiation patterns and relatively high gain over the 2.4/5.2 GHz bands. A two-element configuration was also designed and tested, to firstly increase the gain of the configuration and secondly to facilitate the transformation of the dipole design into a dual-polarized configuration. The second aim of this dissertation was to develop a dual-polarized array, while making use of only two ports, each pertaining to a specific polarization and to implement the design on a single-dielectric-layer substrate. Most dual-polarized structures such as circular, square and annular microstrip antenna designs only support one band, where multi-dielectric-layer structures are the norm. The disadvantages associated with multi-layered designs, such as fabrication difficulties, high costs, high back lobes and the size of the arrays, further supported the notion of developing an alternative configuration. The second contribution was thus the orthogonal interleaving of the two-element array configurations, to address the paucity of single-dielectric-layer dual-band dual-polarized designs that can be implemented with only two ports. This design was first developed and simulated with the aid of the commercial software package CST Microwave Studio® and the results were later corroborated with the measured data obtained from the Compact Antenna Range at the University of Pretoria. AFRIKAANS : Die onlangse groei in die area van moderne draadlose kommunikasie en met spesifieke verwysing na DLAN (Draadlose Lokale Area Netwerk) stelsels, het ‘n nis vir nuwe ontwerpe geskep. Daar word van hierdie nuwe ontwerpe die kapasiteit verlang om verskeie ortogonale polarisasies te stuur en/of te ontvang in samewerking met dubbel-band eienskappe, terwyl ‘n kompakte struktuur nogsteeds aandag moet geniet. Die eerste doel met hierdie verhandeling was dus die ontwikkeling van ‘n dubbel-band enkel stralingselement wat instaat is om die 2.4 GHz (2.4 – 2.484 GHz) band en die 5.2 GHz (5.15 – 5.85 GHz) band wat as die IEEE 802.11b en die IEEE 802.11a DLAN standaarde respektiewelik bekend staan, te bedek. Dubbel-frekwensie elemente soos onder andere die gepakte-, merkkepie- en dichromatiese strook antenne was as moontlike oplossings ondersoek, maar die grootte en hoë kruispolarisasie wat gewoonlik met hierdie ontwerpe gepaard gaan, het die ontwerpsproses in die rigting van verskeie dipool en monopool konfigurasies gestoot. Die aantreklike eienskappe van die verskeie ontwerpe was met mekaar vergelyk, waar die dubbel Rhombus antenna, verwagtend met dubbel-band dubbel-polarisasie potensiaal, as basis vir die ontwikkeling van die DBDP (Dubbel-Band Dubbel-Polarisasie) antenna ontwerp gebruik is. Die enkelelementontwerp het wye bandwydtes, goeie direktiewe stralingspatrone en relatiewe hoë wins oor die 2.4/5.2 GHz bande geopenbaar. Die twee-element konfigurasies was ook ontwerp en getoets om eerstens die wins van die konfigurasie te verhoog en tweedens om die transformasie na ‘n dubbel-gepolariseerde konfigurasie te fassiliteer. Die tweede doel van hierdie verhandeling was om ‘n dubbel-gepolariseerde elementopstelling met net twee poorte te ontwikkel, waar elkeen verantwoordelik is vir ‘n spesifieke polarisasie, en te implementeer op ‘n enkel-diëlektriese-laag substraat. Die meeste dubble-polarisasiestrukture, soos onder andere die sirkulêre-, vierkantige- en ringvormige antenne ontwerpe, kan net een frekwensieband onderhou en word gewoonlik met behulp van meervoudige-diëlektriese-laagstrukture geimplementeer. Die negatiewe eienskappe soos onder andere die vervaardigingsmoeilikhede, hoë kostes, hoë teruglobbe en die grootte van die meervoudige-elementopstellings wat aan hierdie meervoudige-diëlektriese-laagontwerpe behoort, het verder die denkbeeld van ‘n alternatiewe konfigurasie bekragtig. Die tweede hoofbydrae was dus die ortogonale insleuteling van die twee-element meervoudige-elementopstelling konfigurasies om die geringheid van enkel-diëlektriese-laag dubbel-band dubbel-polarisasie ontwerpe, wat net met twee poorte geïmplementeer kan word, te adresseer. Hierdie ontwerp was eers met behulp van die kommersiële sagtewarepakket CST Microwave Studio® ontwikkel en gesimuleer, waarna die resultate bevestig was deur meetings by die Kompakte Antenna Meetbaan van die Universiteit van Pretoria. / Dissertation (MEng)--University of Pretoria, 2011. / Electrical, Electronic and Computer Engineering / unrestricted