The Open-Loop Discounted Linear Quadratic Differential Game for Regular Higher Order Index Descriptor Systems

In this paper we consider the discounted linear quadratic differential game for descriptor systems that have an index larger than one. We derive both necessary and sufficient conditions for existence of an open-loop Nash (OLN) equilibrium. In a small macro-economic stabilization game we illustrate that the corresponding optimal response is generically cyclic.linear quadratic differential games;open-loop information structure;descriptor systems

A modular and extensible RNA-based gene-regulatory platform for engineering cellular function

Engineered biological systems hold promise in addressing pressing human needs in chemical processing, energy production, materials construction, and maintenance and enhancement of human health and the environment. However, significant advancements in our ability to engineer biological systems have been limited by the foundational tools available for reporting on, responding to, and controlling intracellular components in living systems. Portable and scalable platforms are needed for the reliable construction of such communication and control systems across diverse organisms. We report an extensible RNA-based framework for engineering ligand-controlled gene-regulatory systems, called ribozyme switches, that exhibits tunable regulation, design modularity, and target specificity. These switch platforms contain a sensor domain, comprised of an aptamer sequence, and an actuator domain, comprised of a hammerhead ribozyme sequence. We examined two modes of standardized information transmission between these domains and demonstrate a mechanism that allows for the reliable and modular assembly of functioning synthetic RNA switches and regulation of ribozyme activity in response to various effectors. In addition to demonstrating examples of small molecule-responsive, in vivo functional, allosteric hammerhead ribozymes, this work describes a general approach for the construction of portable and scalable gene-regulatory systems. We demonstrate the versatility of the platform in implementing application-specific control systems for small molecule-mediated regulation of cell growth and noninvasive in vivo sensing of metabolite production

Legislative History of the Fair Labor Standards Act

With recent advances in power electronic technology, High-Voltage Direct Current (HVDC) transmission system has become an alternative for transmitting power especially over long distances. Multi-Terminal HVDC (MTDC) systems are proposed as HVDC systems with more than two terminals. These systems can be geographically wide. While in AC grids, frequency is a global variable, in MTDC systems, DC voltage can be considered as its dual. However, unlike frequency, DC voltage can not be equal across the MTDC system. Control of DC voltage in MTDC systems is one of the important challenges in MTDC systems. Since the dynamic of MTDC system is very fast, DC voltage control methods cannot rely only on remote information. Therefore, they can work based on either local information or a combination of local and remote information. In this thesis, first, the MTDC system is modeled. One of the models presented in this thesis considers only the DC grid, and effects of the AC grids are modeled with DC current sources, while in the other one, the connections of the DC grid to the AC grids are also considered. Next, the proposed methods in the literature for controlling the DC voltage are described and in addition to these methods, some control methods are proposed to control the DC voltage in MTDC system. These control methods include two groups. The first group (such as Multi-Agent Control methods) uses remote and local information, while the second group (such as Sliding Mode Control and H¥ control) uses local information.The proposed multi-agent control uses local information for immediate response, while uses remote information for a better fast response. Application of Multi-Agent Control systems leads to equal deviation of DC voltages from their reference values. Using remote information leads to better results comparing to the case only local information is used. Moreover, the proposed methods can also work in the absence of remote information. When AC grid is considered in the modeling, the MTDC system has anon-linear dynamic. Sliding Mode Control, a non-linear control method with high disturbance rejection capability, which is non-sensitive to the parameter variations, is applied to the MTDC system. It controls the DC voltage very fast and with small or without overshoot. Afterward, a static state feedback H¥ control is applied to the system which minimizes the voltage deviation after a disturbance and keeps the injected power of the terminals within the limits. Finally, some case studies are presented and the effectiveness of the proposed methods are shown. All simulations have been done in MATLAB and SIMULINK.QC 20140911</p

Thermodynamic costs of information processing in sensory adaption

Biological sensory systems react to changes in their surroundings. They are characterized by fast response and slow adaptation to varying environmental cues. Insofar as sensory adaptive systems map environmental changes to changes of their internal degrees of freedom, they can be regarded as computational devices manipulating information. Landauer established that information is ultimately physical, and its manipulation subject to the entropic and energetic bounds of thermodynamics. Thus the fundamental costs of biological sensory adaptation can be elucidated by tracking how the information the system has about its environment is altered. These bounds are particularly relevant for small organisms, which unlike everyday computers operate at very low energies. In this paper, we establish a general framework for the thermodynamics of information processing in sensing. With it, we quantify how during sensory adaptation information about the past is erased, while information about the present is gathered. This process produces entropy larger than the amount of old information erased and has an energetic cost bounded by the amount of new information written to memory. We apply these principles to the E. coli's chemotaxis pathway during binary ligand concentration changes. In this regime, we quantify the amount of information stored by each methyl group and show that receptors consume energy in the range of the information-theoretic minimum. Our work provides a basis for further inquiries into more complex phenomena, such as gradient sensing and frequency response.Comment: 17 pages, 6 figure

Wideband and UWB antennas for wireless applications. A comprehensive review

A comprehensive review concerning the geometry, the manufacturing technologies, the materials, and the numerical techniques, adopted for the analysis and design of wideband and ultrawideband (UWB) antennas for wireless applications, is presented. Planar, printed, dielectric, and wearable antennas, achievable on laminate (rigid and flexible), and textile dielectric substrates are taken into account. The performances of small, low-profile, and dielectric resonator antennas are illustrated paying particular attention to the application areas concerning portable devices (mobile phones, tablets, glasses, laptops, wearable computers, etc.) and radio base stations. This information provides a guidance to the selection of the different antenna geometries in terms of bandwidth, gain, field polarization, time-domain response, dimensions, and materials useful for their realization and integration in modern communication systems