Connections Between Adaptive Control and Optimization in Machine Learning

This paper demonstrates many immediate connections between adaptive control and optimization methods commonly employed in machine learning. Starting from common output error formulations, similarities in update law modifications are examined. Concepts in stability, performance, and learning, common to both fields are then discussed. Building on the similarities in update laws and common concepts, new intersections and opportunities for improved algorithm analysis are provided. In particular, a specific problem related to higher order learning is solved through insights obtained from these intersections.Comment: 18 page

Lattice Kinetics of Diffusion-Limited Coalescence and Annihilation with Sources

We study the 1D kinetics of diffusion-limited coalescence and annihilation with back reactions and different kinds of particle input. By considering the changes in occupation and parity of a given interval, we derive sets of hierarchical equations from which exact expressions for the lattice coverage and the particle concentration can be obtained. We compare the mean-field approximation and the continuum approximation to the exact solutions and we discuss their regime of validity.Comment: 24 pages and 3 eps figures, Revtex, accepted for publication in J. Phys.

Posterior Approach To Kidney Dissection: An Old Surgical Approach For Integrated Medical Curricula

Integrated medical curricular changes are altering the historical regional anatomy approach to abdominal dissection. The renal system is linked physiologically and biochemically to the cardiovascular and respiratory systems, yet anatomist often approach the urinary system as part of the abdomen and pelvic regions. As part of an integrated curriculum, the renal system must be covered relatively quickly after the thorax in the cadaver lab, often without the opportunity to fully appreciate the rest of the abdominal contents. This paper provides dissection instructions that follow the one of the historical surgical approaches for nephrectomy, including preservation of the posterior abdominal wall neurovasclature. Dissection procedures were developed for first year medical students, intending this posterior approach to the kidneys to be their first introduction to the renal system. It has been successfully implemented with first year medical students at the University of New England, College of Osteopathic Medicine. Utilizing this posterior approach to the kidney enabled the study of the anatomy of the kidneys, suprarenal glands and renal vessels, as well as the muscles of the lumbar spine, while maintaining the integrity of the anterior abdominal wall and peritoneal cavity for future gastrointestinal and reproductive system-based dissections

Adaptive Control of a Generic Hypersonic Vehicle

This paper presents an adaptive augmented, gain-scheduled baseline LQR-PI controller applied to the Road Runner six-degree-of-freedom generic hypersonic vehicle model. Uncertainty in control effectiveness, longitudinal center of gravity location, and aerodynamic coefficients are introduced in the model, as well as sensor bias and noise, and input time delays. The performance of the baseline controller is compared to the same design augmented with one of two different model-reference adaptive controllers: a classical open- loop reference model design, and modified closed-loop reference model design. Both adaptive controllers show improved command tracking and stability over the baseline controller when subject to these uncertainties. The closed-loop reference model controller offers the best performance, tolerating a reduced control effectiveness of 50%, rearward center of gravity shift of up to -1.6 feet (11% of vehicle length), aerodynamic coefficient uncertainty scaled 4× the nominal value, and sensor bias of up to +3.2 degrees on sideslip angle measurement. The closed-loop reference model adaptive controller maintains at least 70% of the delay margin provided by the robust baseline design when subject to varying levels of uncertainty, tolerating input time delays of between 15-41 ms during 3 degree angle of attack doublet, and 80 degree roll step commands.Approved for Public Release; Distribution Unlimited. Case Number 88ABW-2013-3392

Adaptive Output Feedback Based on Closed-Loop Reference Models for Hypersonic Vehicles

This paper presents a new method of synthesizing an output feedback adaptive controller for a class of uncertain, non-square, multi-input multi-output systems that often occur in hypersonic vehicle models. The main challenge that needs to be addressed is the determination of a corresponding square and strictly positive real transfer function. This paper proposes a new procedure to synthesize two gain matrices that allows the realization of such a transfer function, thereby allowing a globally stable adaptive output feedback law to be generated. The unique features of this output feedback adaptive controller are a baseline controller that uses a Luenberger observer, a closed-loop reference model, manipulations of a bilinear matrix inequality, and the Kalman-Yakubovich Lemma. Using these features, a simple design procedure is proposed for the adaptive controller, and the corresponding stability property is established. The proposed adaptive controller is compared to the classical multi-input multi-output adaptive controller. A numerical example based on a scramjet powered, blended wing-body generic hypersonic vehicle model is presented. The 6 degree-of-freedom nonlinear vehicle model is linearized, giving the design model for which the controller is synthesized. The adaptive output feedback controller is then applied to an evaluation model, which is nonlinear, coupled, and includes actuator dynamics, and is shown to result in stable tracking in the presence of uncertainties that destabilize the baseline linear output feedback controller.This research is funded by the Air Force Research Laboratory/Aerospace Systems Directorate grant FA 8650-07-2-3744 for the Michigan/MIT/AFRL Collaborative Center in Control Sciences and the Boeing Strategic University Initiative. Approved for Public Release; Distribution Unlimited. Case Number 88ABW- 2014-2551

Preliminary Report: Evaluating the Potential of Archaeogeophysical Surveying on Viking Age and Medieval Sites in Greenland, 2 – 16 August, 2010

The primary goal of this research is to begin to overcome biases in the Greenlandic Norse archaeological record. Assessing the establishment dates and organization of Norse sites in Greenland is difficult because substantial cultural deposits can be hidden under deep windblown sand deposits as well as later occupations. Shallow geophysical methods were used to help recover information on the nature, extent and depth of subsurface cultural deposits. Assessing these site characteristics is a first step in overcoming the bias towards the later, the larger, and the more visible sites in the archaeological record. Norse Greenland presents a relatively visible medieval landscape with many ruins preserved on the surface. Survey archaeologists have taken advantage of these conditions to do comprehensive surveys of Norse settlements producing inventories of farm buildings and settlements (Guldager, et al. 2002; Keller 1990). Coring surveys and excavation at known sites have demonstrated that some sites are buried under significant aeolian deposits and that areas within many other sites can be deep and contain ruins that are not visible on the surface. In many cases Viking Age deposits cannot be accessed by archaeological excavation, as this would damage later occupational phases. In these cases, application of archeogeophysics may be the only way to assess this unique cultural history. The identification, characterization, and dating of these subsurface architectural remains are critical to systematic survey programs and to the production of regional settlement patterns and chronologies that can help explain the ecological and political dynamics of Norse colonization, land use, and the eventual demise of Norse Greenland. Over the past 10 years the Skagafjörður Archaeological Settlement Survey (SASS) has developed an intensive subsurface survey protocol to systematically recover, date, and characterize Viking Age landscapes in Iceland. While we believe the SASS subsurface protocol can be effective in Greenland there are many questions that must be resolved before any wide-scale application of the methods can be developed. The project set out to address two basic questions: (1) what is the actual subsurface record at Norse sites, and (2) which methods work best and how are they most effectively employed? In this initial investigation, we tested and adapted this protocol to conditions in Greenland. We hope that the preliminary test of these methods will significantly expand the range of sites and periods accessible to researchers working in Greenland and allow for new questions regarding the long-term political and environmental histories of the region. The successful integration of archaeogeophysics with archaeological survey and excavation will result in a more holistic approach to the preservation of Norse archaeological sites in Greenland. These sites suffer from increased modern impacts resulting from mineral exploitation, sheep farming, and tourism. Additionally, there is now total summer sub-surface thaw and conditions that were once ideal for preserving organic remains are now deteriorating, especially in well-drained areas. In the coming years the Greenland National Museum will begin a program of scheduling and protecting some of these sites. We believe that the application of archaeogeophysics could be a great asset in determining which sites are in danger and worthy of preservation

Pengembangan Instrumen Pendeteksi Kesulitan Belajar Kimia Kelas X Menggunakan Model Testlet

Penelitian ini bertujuan untuk: (1) menghasilkan instrumen model testlet sebagai instrumen pendeteksi kesulitan belajar kimia peserta didik kelas X SMA sesuai tahapan penelitian pengembangan; (2) menentukan karakteristik butir soal instrumen pendeteksi kesulitan belajar kimia kelas X menggunakan model testlet; (3) mendapatkan profil belajar individu peserta didik. Penelitian ini merupakan penelitian pengembangan model Akker dengan tahapan: preliminary investigation; theoretical embedding; empirical testing; dan documentation, analysis, and reflection on process and outcome. Subjek uji coba yaitu guru kimia SMA di Surakarta; dosen Pendidikan Kimia FKIP UNS Surakarta; peserta didik SMA Negeri 2, SMA Negeri 5, dan SMA Batik 2 Surakarta. Berdasarkan hasil penelitian dapat disimpulkan bahwa: (1) penelitian ini menghasilkan instrumen pendeteksi kesulitan belajar kimia kelas X menggunakan model testlet pada bab Struktur Atom dan Sistem Periodik Unsur yang terdiri dari butir soal dan program analisis datanya; (2) karakteristik butir soal memiliki validitas isi Aiken dengan rentang 0,76-1 yang berarti validitas isi baik; reliabilitas sebesar 0,83 yang berarti reliabilitas tinggi; persentase daya beda soal baik sekali 47,91%, baik 12,5%, cukup 18,75%, jelek 20,83%; persentase tingkat kesukaran soal sukar 4,17%, sedang 50%, mudah 45,83%; dan kunci jawaban 70,83% efektif; (3) profil belajar individu peserta didik dapat memberi laporan yang informatif mengenai kemampuan dan kesulitan belajar kimia peserta didik