Effects of circadian rhythm phase alteration on physiological and psychological variables: Implications to pilot performance (including a partially annotated bibliography)

The effects of environmental synchronizers upon circadian rhythmic stability in man and the deleterious alterations in performance and which result from changes in this stability are points of interest in a review of selected literature published between 1972 and 1980. A total of 2,084 references relevant to pilot performance and circadian phase alteration are cited and arranged in the following categories: (1) human performance, with focus on the effects of sleep loss or disturbance and fatigue; (2) phase shift in which ground based light/dark alteration and transmeridian flight studies are discussed; (3) shiftwork; (4)internal desynchronization which includes the effect of evironmental factors on rhythmic stability, and of rhythm disturbances on sleep and psychopathology; (5) chronotherapy, the application of methods to ameliorate desynchronization symptomatology; and (6) biorythm theory, in which the birthdate based biorythm method for predicting aircraft accident susceptability is critically analyzed. Annotations are provided for most citations

Safe and Scalable Learning-Based Control: Theory and Application in Sustainable Energy Systems

From intelligent transportation systems to the smart grid, the next generation of cyber-physical systems (CPS) will substantially transform our society. It is vital that these systems are scalable and robust to uncertainties, with contextual awareness and fast adaptation. This dissertation presents progress towards addressing key challenges arising in the control of large-scale CPS, with a special focus on applications in sustainable energy systems. Large-scale CPS such as the smart grid often consist of numerous interconnected and heterogeneous subsystems that must coordinate to achieve global objectives by exchanging information over a communication network. Therefore, the first part of this thesis focuses on developing control algorithms that handle crucial design requirements emerging from scalability and communication constraints, such as disturbance localization, communication delay conformation, and distributed implementation. Sustainable energy systems are crucial for reducing greenhouse gas emissions and mitigating climate change. However, the inherent unpredictability and large uncertainties associated with renewable generation pose significant challenges for maintaining system stability and safety. Traditional control approaches, while robust and effective for known system models, often fall short when faced with the dynamic and uncertain nature of modern power systems. In the second part of the thesis, we address this challenge by integrating machine learning techniques with model-based control methods using uncertainty sets constructed from real-time data. In particular, we will introduce and provide convergence guarantees for a classic uncertainty set estimation method. Building on these uncertainty sets, we combine learning and control techniques to tackle core CPS control problems, such as adversarial stability certification for linear time-varying systems as well as networked systems under communication constraints where the system models are unknown. The final part of this thesis applies the developed methodologies to address the voltage control problem in power distribution networks with unknown grid topologies. We will combine online learning techniques and a robust predictive controller to achieve provably finite-time convergence to safe voltage limits, despite uncertainties in network topology and load variations. Our case study on a Southern California Edison 56-bus distribution system demonstrates the effectiveness of this approach in nonlinear, partial observation, and partial control settings.</p

Combustion instabilities in liquid-fuelled propulsion systems

Combustion of reactants in a confined volume favors excitation of unsteady motions over a broad range of frequencies. A relatively small conversion of the energy released will produce both random fluctuations or noise, and, under many circumstances, organized oscillations generically called combustion instabilities. Owing to the high energy densities and low losses in combustion chambers designed for propulsion systems, the likelihood of combustion instabilities is high. The accompanying heat transfer to exposed surfaces, and structural vibrations are often unacceptable, causing failure in extreme cases. This paper is a brief review of combustion instabilities in liquid-fueled propulsion systems-rockets, ramjets, and thrust augmentors-with emphasis on work accomplished during the past decade. To provide a common framework for discussing the wide range of works, a theory of two-phase flow is reviewed as the basis for an approximate analysis of combustion instabilities. The analysis is directed primarily to treatment of linear stability; it is sufficiently general to accommodate all processes occurring in actual systems. A new result has been obtained for an extended form of Rayleigh's criterion and its relation to the growth constant for unstable waves. The chief mechanisms for combustion instabilities in liquid-fueled systems are reviewed, followed by a summary of the common methods of analysis and applications to the three classes of propulsion systems. Control of instabilities by passive and active means is examined briefly

Technology for large space systems: A bibliography with indexes (supplement 20)

This bibliography lists 694 reports, articles, and other documents introduced into the NASA Scientific and Technical Information System between July, 1988 and December, 1988. Its purpose is to provide helpful information to the researcher or manager engaged in the development of technologies related to large space systems. Subject areas include mission and program definition, design techniques, structural and thermal analysis, structural dynamics and control systems, electronics, advanced materials, assembly concepts, and propulsion

Voyager spacecraft system. Preliminary design, volume B /book 3 of 3/ - Alternate designs considered - G and C, Pwr, C and S, prop, plans

Alternate designs for guidance and control, power, controller and sequencer systems for Voyager spacecraft - effect of alternate designs on schedule and implementatio

Aeronautical engineering: A continuing bibliography with indexes (supplement 267)

This bibliography lists 661 reports, articles, and other documents introduced into the NASA scientific and technical information system in June, 1991. Subject coverage includes design, construction and testing of aircraft and aircraft engines; aircraft components, equipment and systems; ground support systems; theoretical and applied aspects of aerodynamics and general fluid dynamics; electrical engineering; aircraft control; remote sensing; computer sciences; nuclear physics; and social sciences