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A modified printed bow-tie antenna is designed to simultaneously cover the operations in the C and X-bands from 5.5 to 12.5 GHz. The presented antenna has an end fire radiation pattern that makes it suitable for integration in single and dual polarized phased array systems. The antenna exhibits small size and wide bandwidth of 91%. The radiation characteristics are presented for a single element and a linear array of this antenna. Index Terms--Bow-tie, dual polarization, phased arrays, radar, wideband.

A dual tapered meander slot antenna (TMSA) is designed for use as an element in a phased array antenna system for RF and microwave sensors and radar applications. The novel design of dual TMSA element, excited by a coplanar waveguide (CPW) feed, provides a wide band and high efficiency characteristics with 50 [OMEGA] input impedance at 10 GHz operating frequency. Index Terms--Broadband antennas, meander antenna, slot antenna.

Analysis of geometrically complicated waveguide-based slotted arrays and filters is performed using a simple equivalent-circuit model. First, the circuit parameters (inductance and capacitance) of a simple waveguide slot-coupler problem are obtained through moment-method (MoM) analysis. The values of the lumped LC elements are virtually constant over the frequency range of interest (the X-band) for specific waveguide and slot dimensions. Based on the equivalent-circuit model of a single slot of two coupled waveguides, more complicated structures are then analyzed, such as slot coupler arrays and slot-based waveguide filters. The scattering parameters of these structures are obtained through circuit analysis, and are verified using the MoM and finite-difference time-domain method. Excellent agreement is observed over a wide band of frequencies and is confirmed by experimental results. Index Terms--Equivalent circuits, moment methods (MoMs), rectangular waveguides, slot arrays, waveguide filters.

The V transmission line was analyzed using a Yee-cell based finite-difference time-domain method to determine its characteristics for higher frequency ranges. Results showed that the V line is less dispersive than conventional microstrip lines, thus allowing faster propagation of signals. The most significant feature of the V line is the low coupling between adjacent lines, which makes it highly applicable to high density packaging.

Little of the considerable research devoted to the connections between the Supreme Court and the mass public has addressed popular attitudes toward nominees to the High Bench. Here we hope to stimulate interest in this important and understudied area by examining the wellsprings of opinionation and sentiment toward the confirmation of Justice Clarence Thomas. Relying on data from CBS News/New York Times polls and using statistical models of opinion-holding and support for Thomas' confirmation, we examine whether citizen attitudes were grounded in policy preferences, political orientations of long-standing such as partisanship, ideological convictions, group ties, and presidential approval. We also develop and directly link a model of the formation of opinion toward the nomination a model of activation, in which citizens assimilate information and form an opinion - with a model of sentiment, in which citizens develop a positive or negative feeling toward the nominee. We report dramatic and systematic shifts in the sources of opinion mobilization which accord well with the intuitive expectations that flow from the temporal order of events and controversies associated with this battle. We find, among the mobilized, substantial and enduring associations between sentiment toward Thomas and summary political orientations, attitudes toward the president, and policy preferences. We also see shifts in the demography of Thomas' support; and, again, these findings accord well with expectations derived from the dynamics of the conflict over the nomination.

The SPICE circuit analysis program has limited math capability and, in general, cannot be used for RF and microwave simulation because complex arithmetic is required to compute S-parameters from node voltages. This paper presents two models of a directional coupler that can be used to obtain node voltages proportional to incident, reflected, and transmitted signals. These models are based on a previously developed multiple coupled transmission line (MTL) SPICE model. From SPICE computed node voltages, S-parameters are computed using the math capability of the PSPICE post processor, PROBE, as an example for a low-pass filter consisting of transmission line sections. The results of this example are compared with another high-frequency circuit analysis program, TOUCHSTONE. The difference between the results of these two programs in magnitude was less than 0.005 and in phase was a few tenths of a degree. By using these couplers to simulate a network analyzer, RF and microwave analysis can be made with SPICE, which can be a cost-effective and readily available computational tool for educators and practicing engineers.

Great improvements in quality management, technical innovation and profitability can be achieved when managers manage to change people's views on the limits of what is possible in the future. This process of organisational leadership using strategic intent can be designated the 'Merlin Factor', encouraging old habits to abandoned and ensuring that others become committed to the introduction of a new collective purpose. The strategy is based on the assumption that what is chosen for the future is more important than knowledge of past or current capabilities.

A numerical analysis of two-conductor transmission line with a rectangular notch in the dielectric between the strips is presented. Three media integral equations are derived and solved for the charge distributions. The decoupling between such two-conductor coupled microstrip transmission line is investigated for asymmetric conductors. It is found that the coupling between two conducting lines can be reduced significantly by removing dielectric material between the lines which has a rectangular shape. For best decoupling, the width should be as wide as possible between the conducting lines but the depth should have an optima somewhere in the base dielectric substrate.

The three coefficients of restitution used in the analysis of post-collision motion in a mechanical system are evaluated. Thekinetic energy of the system is expressed in terms of the partial velocities ofcolliding rigid bodies and the resulting equation is then used to test the accuracy of the different coefficients of restitutions. The amount of friction,the direction of the approach velocity and the inertial behavior of the system are found to have significant effects on the reliability of the coefficients ofrestitution.

The primary source of divided government in the United States is voters who split their ballots between the parties. Yet there has been little comprehensive examination of either patterns or sources of ticket splitting in recent years. Instead, divergent lines of research have emerged, emphasizing such things as voter partisanship, incumbency, and a 'new' (young, well-educated, even partisan) kind of ticket splitter; and their focus has been too often restricted to the atypical president - Congress pair. We seek to unify these research traditions in a comprehensive model of split-ticket voting and to test this model across the partisan ballot in a typical election setting - here, the contests for five Ohio state-wide offices in 1990. The model incorporates partisan strength, candidate visibility, and the individual characteristics that distinguish the 'new ticket splitters'. The results support our partisan strength and candidate visibility explanations but provide little support for the emergence of a new type of ticket splitter.

Utilizing frequent measurements taken during a period of considerable economic volatility, our research explores how short-term fluctuations in partisanship have operated and continue to operate within a limited range before permanent realignment occurs. Specifically, we examine monthly fluctuations in the aggregate distribution of partisan identifiers between 1981 and 1986. We show that there were systematic changes in the partisan balance during the period, and confirm the MacKuen, Erikson, and Stimson (1989) finding that changes in presidential popularity account for some of the movement. Further, we detail economic influences in macropartisanship using objective indicators. The results show that both inflation and unemployment bear directly on the partisan balance, and that each exerts an indirect influence through presidential popularity.

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1467-8616.2007.00490.x Byline: Charles E. Smith (1) Abstract: Should executive coaches think of themselves as filling the same role Merlin did with King Arthur?Charles E. Smith would insist on it. Author Affiliation: (1)(merlininstitute@gmail.com) is the author of The Merlin Factor: Keys to the Corporate Kingdom (Gower, 1997). He is a strategic partner of the McLane Group in Manchester, UK, and director of the Merlin Institute in Windermere, Florida.

This paper presents a design for a male or female BNC-to-Microstrip transition for use in high frequency and microwave undergraduate laboratories. Measured data is provided to verify electrical characteristics.

Vector network analyzers have evolved as the measurement system of choice for microwave industry use. However, network analyzers are not usually covered in undergraduate laboratories, primarily because of cost and reluctance of instructors to move away from slotted line techniques, and the associated visual representation of standing waves. To bridge the gap between these technologies, a computer program has been developed for controlling a network analyzer to display standing waves as visualized on slotted lines for impedance measurements. The program, NASWAVE, provides this visualization of standing waves for instructional purposes so that students actually see the waveforms similar to the response obtained with slotted line measurements. The equations used for computation and display of the standing waves are presented. The software operation and use is discussed and examples are also presented. Index Terms--BASIC language, impedance, network analyzers, slotted lines, Smith chart, standing waves, transmission lines, voltage standing wave ratio.

This paper presents a set of simplified equations based on a four-port scattering model, which accurately characterizes four-pair twisted pair (eight-port) cabling systems for high-speed digital telecommunication local area networks. These equations are derived and simplified from two-stage cascaded four-port S-parameter matrices and verified experimentally. Excellent agreement is obtained between the measurements and computational results when the S-parameters of the cabling system components are known. These equations not only reduce the computation burdens in comparison with traditional methods for transmission matrix computations, but also provide intuition of the contributions of the S-parameters at each stage in the net crosstalk, return loss, and insertion loss. Furthermore, these equations can be used to compute the component specifications when the system performance is specified, and to obtain the deembedded system characteristics by subtracting the known characteristics of adapters. Index Terms--Four-port scattering parameters, twisted-pair cabling system.

Protease-activated receptors (PARs) represent a unique family of seven-transmembrane G protein-coupled receptors, which are enzymatically cleaved to expose a truncated extracellular N terminus that acts as a tethered activating ligand. PAR-1 is cleaved and activated by the serine protease [Alpha]-thrombin, is expressed in various tissues (e.g., platelets and vascular cells), and is involved in cellular responses associated with hemostasis, proliferation, and tissue injury. We have discovered a series of potent peptide-mimetic antagonists of PAR-1, exemplified by RWJ-56110. Spatial relationships between important functional groups of the PAR-1 agonist peptide epitope SFLLRN were employed to design and synthesize candidate ligands with appropriate groups attached to a rigid molecular scaffold. Prototype RWJ-53052 was identified and optimized via solid-phase parallel synthesis of chemical libraries. RWJ-56110 emerged as a potent, selective PAR-1 antagonist, devoid of PAR-1 agonist and thrombin inhibitory activity. It binds to PAR-1, interferes with PAR-1 calcium mobilization and cellular function (platelet aggregation; cell proliferation), and has no effect on PAR-2, PAR-3, or PAR-4. By flow cytometry, RWJ-56110 was confirmed as a direct inhibitor of PAR-1 activation and internalization, without affecting N-terminal cleavage. At high concentrations of [Alpha]-thrombin, RWJ-56110 fully blocked activation responses in human vascular cells, albeit not in human platelets; whereas, at high concentrations of SFLLRN-[NH.sub.2], RWJ-56110 blocked activation responses in both cell types. Thus, thrombin activates human platelets independently of PAR-1, i.e., through PAR-4, which we confirmed by PCR analysis. Selective PAR-1 antagonists, such as RWJ-56110, should serve as useful tools to study PARs and may have therapeutic potential for treating thrombosis and restenosis.

We extend Fiorina's balancing theory by developing and testing inferences from a simple and general spatial model of partisan preference in two institutional dimensions. This model contains a number of theoretical and methodological insights that have not yet been articulated in the growing literature on the origins of divided government. We focus here on the model's most basic implications, emphasizing first that the act of party balancing requires that voters have nonseparable partisan preferences across the electoral arenas of U.S. government. We show how it follows that the institution-specific partisan preferences of balancers are not defined on the metric that contains the partisan preferences of nonbalancers. We examine the empirical relevance of this result by estimating a variety of statistical models of congressional voting preference. Analysis proceeds in two directions, first with illustrations of a changepoint (and a resultant heteroskedastic error variance) problem in simple models of voter choice and then with results from more elaborate model specifications. The evidence weighs heavily in favor of the empirical relevance of party balancing in the 1996 congressional election. We conclude by pointing to a number of theoretical and methodological issues that merit further attention in future research on balancing.

The use of digital oscilloscopes having print/plot capability is discussed in reference to data acquisition in the undergraduate laboratory. These instruments can increase productivity in the laboratory while keeping the data acquisition system almost transparent to the user.

The design for a cost effective ammeter protection circuit uses an operational amplifier/zener diode circuit to limit voltage across the meter. This is more effective than the standard parallel connections used for ammeters in electric circuits instructional laboratories. The design and derivations for a meter protection circuit for 50 and 100 milliamp meter movements are shown.

We live today in the midst of major educational reform in this country. In many states, legislation designed to improve education has been enacted. On the surface at least all [...]

In systems of governance such as the one in the United States, where there is a separation of powers and where separate elections determine who will control the distinct institutions, [...]