Kalman Filtering With Relays Over Wireless Fading Channels

This note studies the use of relays to improve the performance of Kalman filtering over packet dropping links. Packet reception probabilities are governed by time-varying fading channel gains, and the sensor and relay transmit powers. We consider situations with multiple sensors and relays, where each relay can either forward one of the sensors' measurements to the gateway/fusion center, or perform a simple linear network coding operation on some of the sensor measurements. Using an expected error covariance performance measure, we consider optimal and suboptimal methods for finding the best relay configuration, and power control problems for optimizing the Kalman filter performance. Our methods show that significant performance gains can be obtained through the use of relays, network coding and power control, with at least 30-40$\%$ less power consumption for a given expected error covariance specification.Comment: 7 page

Optical properties of an atomic ensemble coupled to a band edge of a photonic crystal waveguide

We study the optical properties of an ensemble of two-level atoms coupled to a 1D photonic crystal waveguide (PCW), which mediates long-range coherent dipole-dipole interactions between the atoms. We show that the long-range interactions can dramatically alter the linear and nonlinear optical behavior, as compared to a typical atomic ensemble. In particular, in the linear regime, we find that the transmission spectrum reveals multiple transmission dips, whose properties we show how to characterize. In the many-photon regime the system response can be highly non-linear, and under certain circumstances the ensemble can behave like a single two-level system, which is only capable of absorbing and emitting a single excitation at a time. Our results are of direct relevance to atom-PCW experiments that should soon be realizable

Learning Medicine by the Book: Reading and Writing Surgical Manuals in Early Modern London

Centred on Thomas Brugis's popular Vade mecum, or A Companion for a Chyrurgion fitted for times of Peace or War (1651), this essay considers the role of the instructional book in early modern surgical knowledge and practice. By tracing the fortuna of the Vade mecum from production to use, it shows that, far from being static texts, instructional books were dynamic objects responding and adapting to the changing needs of knowledge communities. I begin by situating the Vade mecum within surgical practice more broadly in early modern England, which shows the key role that the practices of translation and compilation played in the production of surgical manuals. Most producers of surgical manuals were practitioners-turned-authors, and their works typically drew on a mix of lived experience both at the bedside and in the library. Brugis, who was exemplary in this respect, was particularly interested in providing instructions for hands-on practices involved in surgical operations and medicine production. In the last section, which focuses on readers and users, I analyse annotations and additional writings in surviving copies of the Vade mecum to recover the agency of reader–practitioners and trace collective ownership of the book across time and space

Game-Theoretic Pricing and Selection with Fading Channels

We consider pricing and selection with fading channels in a Stackelberg game framework. A channel server decides the channel prices and a client chooses which channel to use based on the remote estimation quality. We prove the existence of an optimal deterministic and Markovian policy for the client, and show that the optimal policies of both the server and the client have threshold structures when the time horizon is finite. Value iteration algorithm is applied to obtain the optimal solutions for both the server and client, and numerical simulations and examples are given to demonstrate the developed result.Comment: 6 pages, 4 figures, accepted by the 2017 Asian Control Conferenc

An Optimal Transmission Strategy for Kalman Filtering over Packet Dropping Links with Imperfect Acknowledgements

This paper presents a novel design methodology for optimal transmission policies at a smart sensor to remotely estimate the state of a stable linear stochastic dynamical system. The sensor makes measurements of the process and forms estimates of the state using a local Kalman filter. The sensor transmits quantized information over a packet dropping link to the remote receiver. The receiver sends packet receipt acknowledgments back to the sensor via an erroneous feedback communication channel which is itself packet dropping. The key novelty of this formulation is that the smart sensor decides, at each discrete time instant, whether to transmit a quantized version of either its local state estimate or its local innovation. The objective is to design optimal transmission policies in order to minimize a long term average cost function as a convex combination of the receiver's expected estimation error covariance and the energy needed to transmit the packets. The optimal transmission policy is obtained by the use of dynamic programming techniques. Using the concept of submodularity, the optimality of a threshold policy in the case of scalar systems with perfect packet receipt acknowledgments is proved. Suboptimal solutions and their structural results are also discussed. Numerical results are presented illustrating the performance of the optimal and suboptimal transmission policies.Comment: Conditionally accepted in IEEE Transactions on Control of Network System

Assessing the Cross-Cultural Reliability and Validity of a Measure of Parent Satisfaction Among Head Start Caregivers

Accurately assessing caregiver satisfaction in their child’s education creates an opportunity for two-sided conversations between caregivers and schools that fosters active family involvement in education. In response to the need for accurate assessment of caregiver satisfaction, Fantuzzo, Perry and Childs (2006) created the Parent Satisfaction in Educational Experiences Scale (PSEE) specifically for low-income caregivers of preschool aged children attending Head Start preschool programs as well as caregivers of kindergarten students. Although the PSEE presents an opportunity to engage caregivers, the measure has not yet been validated on a sufficient sample of men or a sample of caregivers born outside of the US. This pilot study examines cross-gender and cross-birthplace reliability and validity of the PSEE, as well as an analysis of the three submeasures embedded within the PSEE. The study draws from a small sample of N=141 diverse, urban Head Start caregivers. 22.7% of caregivers identified as male and the remaining 77.3% identified as female. 52.1% of caregivers were born outside of the US, hailing from 15 different countries. To account for language barriers in caregivers born outside the US, the PSEE was administered in the five most predominant languages: English, Spanish, Cape Verdean Creole, Haitian Creole and Vietnamese. Analysis indicates the PSEE maintains strong reliability in caregivers born outside of the US but lower reliability scores in male caregivers. Cronbach’s alpha levels for submeasures within the PSEE drop to low levels in the small sample of men born inside the US. Factor analysis show the proposed three-factor solution of the PSEE does not maintain good fit among this highly diverse sample. This study highlights the strengths of the PSEE in assessing caregiver satisfaction among immigrant families while drawing attention to the need for further research into validating the PSEE among male caregivers

Peran Komunikasi Orang Tua Dalam Melestarikan Bahasa Tonsawang Di Desa Tombatu II Tengah Kecamatan Tombatu Utara Kabupaten Minahasa Tenggara

The role of parental communication in preserving language Tonsawang. Introduction: communication plays an important role in human life. Most of the communication activities that we do takes place in a situation of interpersonal communication. The importance of the role of parental communication, more specifically in preserving language Tonsawang especially to the youth as the next generation. The role of parents is very influential to the younger generation to teach, provide an understanding of the language Tonsawang so willing to learn and preserve the language Tonsawang. Theory and Methods: This Study uses symbolic interaction theory and methods of qualitative research. Results: the role of parent communication is very dominant in the use of language to communicate Tonsawang daily compared to the younger generation, this is quite reasonable because the parents in the village of Central II Tombatu more proficient Tonsawang. Suggestion: the role of parental communication in preserving the language Tonsawang need to be increased again, by increasing the intensity of use Tonsawang language when communicating with childrens, young people, so that they are more aware of the language

Robust-fidelity atom-photon entangling gates in the weak-coupling regime

We describe a simple entangling principle based on the scattering of photons off single emitters in one-dimensional waveguides (or extremely-lossy cavities). The scheme can be applied to photonic qubits encoded in polarization or time-bin, and features a filtering mechanism that works effectively as a built-in error-correction directive. This automatically maps imperfections from weak couplings, atomic decay into undesired modes, frequency mismatches, or finite bandwidths of the incident photonic pulses, into heralded losses instead of infidelities. The scheme is thus adequate for high-fidelity maximally entangling gates even in the weak-coupling regime. These, in turn, can be directly applied to store and retrieve photonic-qubit states, thereby completing an atom-photon interface toolbox, or to sequential measurement-based quantum computations with atomic memories.Comment: 5 pages, 2 figure