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Refinement or improvement of a dynamic system to meet a frequency response specification can benefit from the option to use passive or active compensation, or a combination of both. The process becomes more effective when supplemented with methods derived from classical network theory to synthesize candidate designs for actuators and their control systems. The synthesis procedure presented here provides an explicit way to formulate system topologies that employ passive and active elements to achieve a desired targeted performance specification, i.e., frequency response. Active elements are used to represent elements that are not physically realizable, such as negative impedances and elements that have ill-defined connectivity. A working premise is that these elements indicate the need for actuation technology. Coupled with a topological description of the system, the synthesis procedure provides a systematic approach that offers design solutions not previously conceived of through insight or experience. These 'first draft' designs can be improved upon by later utilizing complementary approaches, such as optimization methods, as dictated by detailed system requirements and operating regimes. The flexibility of this synthesis approach allows the consideration of design restrictions unrelated to frequency response, but critical nonetheless in assessing the viability of candidate designs. Further, the procedure does not require assumption of a particular control/compensation architecture at the outset; this renders novel architectures that depart from traditional architectures such as proportional integral, propotional-integral-derivative, etc. The procedure is couched within a simulation basis, so that extension to state-space simulation and thus growth of the system and inclusion of more complex and nonlinear representations become possible. The concept of a virtual state space is introduced, which is integral to the development of controller architectures and associated parameters. It is found that customized passive/active compensation systems can be derived using a bond graph approach, making this approach more easily applicable to multi-energetic systems. Examples are used to demonstrate the approach, including a case study of an electromechanical vehicle suspension, from which an experimental model is derived to illustrate the synthesis procedure. Comparison of results between these examples illustrate the practical utility of the synthesis procedure. In particular, simulations reveal that increasing the number of realized passive elements for a particular system does not necessarily minimize actuator energy consumption. Detailed analysis of synthesis results show that certain design candidates feature active devices that work against either passive elements or other active devices within the system. [DOI: 10.1115/1.3089558]

Early in his career, O’Neill aspired to be a popular playwright. This contrasts with the conventional assessment of O’Neill’s ambitions. These earliest plays drawing on popular melodrama and relying on explicitly commercial theatrical inspiration do not fit the established model of the O’Neill who insisted he wanted “to be an artist” or nothing. The plays also draw on the influence of Dumas’ La dame aux camélias, O’Neill was been influenced by Ibsen and Strindberg in his later works, but these plays reveal these influences from the start. Finally, they demonstrate that O’Neill had family relationships that had nothing to do with the autobiography in Long Day’s Journey into Night. O’Neill intended “Recklessness” as a possible vehicle for his father. O’Neill is better placed in the context of late 19th and early 20th century theatre; continuing to regard him as sui generis, hobbles our understanding of American theatre and O’Neill’s genius. [ABSTRACT FROM AUTHOR]

Review of Daniel Albright. Putting Modernism Together. Literature, Music, and Painting, 1872-1927. Baltimore: The Johns Hopkins UP, 2015., Daniel Albright. Putting Modernism Together. Literature, Music, and Painting, 1872-1927. Baltimore: The Johns Hopkins UP, 2015. 328 pp. 'Putting Modernism Together' was the title of a popular undergraduate course in [...]

We established HEK-293 cell lines that stably express functional canine ether-a-go-go-related gene (cERG) [K.sup.+] channels and examined their biophysical and pharmacological properties with whole cell patch clamp and [sup.35]S-labeled MK-499 ([[sup.35]S]MK-499) binding displacement. Functionally, cERG current had the hallmarks of cardiac delayed rectifier [K.sup.+] current ([I.sup.Kr]). Channel opening was time- and voltage dependent with threshold near -40 mV. The half-maximum activation voltage was -7.8 [+ or -] 2.4 mV at 23[degrees]C, shifting to -31.9 [+ or -] 1.2 mV at 36[degrees]C. Channels activated with a time constant of 13 [+ or -] 1 ms at +20 mV, showed prominent inward rectification at depolarized potentials, were highly [K.sup.+] selective ([Na.sup.+]-to-[K.sup.+] permeability ratio = 0.007), and were potently inhibited by [I.sup.Kr] blockers. Astemizole, terfenadine, cisapride, and MK-499 inhibited cERG and human ERG (hERG) currents with I[C.sub.50] values of 1.3, 13, 19, and 15 nM and 1.2, 9, 14, and 21 nM, respectively, and competitively displaced [[sup.35]S]MK-499 binding from cERG and hERG with I[C.sub.50] values of 0.4, 12, 35, and 0.6 nM and 0.8, 5, 47, and 0.7 nM, respectively, cERG channels had biophysical properties appropriate for canine action potential repolarization and were pharmacologically sensitive to agents known to prolong QT. A novel MK-499 binding assay provides a new tool to detect agents affecting ERG channels. ion channels; acquired long QT syndrome, potassium ion channel; ventricular arrhythmia; canine ether-a-go-go-related gene

The control structure for automated vehicles in an Automated Highway System is based on the idea of multiple-surface sliding control. The 'upper' surface determines a desired net torque while the 'lower' surface determines the required throttle angle or brake pressure needed to achieve the desired torque. This paper presents an upper surface control law for performing longitudinal transition maneuvers. The maneuvers use desired velocity trajectories which are based on maintaining safety and comfort throughout the maneuver. The control law chosen is a sliding controller due to the nonlinearities in the dynamics and the uncertainties in the parameters. Adaptive techniques were also implemented to help improve the velocity tracking. The controller was implemented on experimental vehicles and tested at highway speeds.

TOOLSTONE GEOGRAPHY OF THE PACIFIC NORTHWEST edited by Terry L. Ozbun and Ron L. Adams Archaeology Press, Simon Fraser University, Burnaby, British Columbia, 2015. Illustrations, photographs, maps, tables, notes. $55.00, [...]

The purpose of this study (cf. Connolly 1986) is to organize the archaeological data from the region into an explicit, and broadly applicable, culture-historical model.