Coupled resonator based wireless power transfer for bioelectronics

Implantable and wearable bioelectronics provide the ability to monitor and modulate physiological processes. They represent a promising set of technologies that can provide new treatment for patients or new tools for scientific discovery, such as in long-term studies involving small animals. As these technologies advance, two trends are clear, miniaturization and increased sophistication i.e. multiple channels, wireless bi-directional communication, and responsiveness (closed-loop devices). One primary challenge in realizing miniaturized and sophisticated bioelectronics is powering. Integration and development of wireless power transfer (WPT) technology, however, can overcome this challenge. In this dissertation, I propose the use of coupled resonator WPT for bioelectronics and present a new generalized analysis and optimization methodology, derived from complex microwave bandpass filter synthesis, for maximizing and controlling coupled resonator based WPT performance. This newly developed set of analysis and optimization methods enables system miniaturization while simultaneously achieving the necessary performance to safely power sophisticated bioelectronics. As an application example, a novel coil to coil based coupled resonator arrangement to wirelessly operate eight surface electromyography sensing devices wrapped circumferentially around an able-bodied arm is developed and demonstrated. In addition to standard coil to coil based systems, this dissertation also presents a new form of coupled resonator WPT system built of a large hollow metallic cavity resonator. By leveraging the analysis and optimization methods developed here, I present a new cavity resonator WPT system for long-term experiments involving small rodents for the first time. The cavity resonator based WPT arena exhibits a volume of 60.96 x 60.96 x 30.0 cm3. In comparison to prior state of the art, this cavity resonator system enables nearly continuous wireless operation of a miniature sophisticated device implanted in a freely behaving rodent within the largest space. Finally, I present preliminary work, providing the foundation for future studies, to demonstrate the feasibility of treating segments of the human body as a dielectric waveguide resonator. This creates another form of a coupled resonator system. Preliminary experiments demonstrated optimized coupled resonator wireless energy transfer into human tissue. The WPT performance achieved to an ultra-miniature sized receive coil (2 mm diameter) is presented. Indeed, optimized coupled resonator systems, broadened to include cavity resonator structures and human formed dielectric resonators, can enable the effective use of coupled resonator based WPT technology to power miniaturized and sophisticated bioelectronics

Characterization of low-noise quasi-optical SIS mixers for the submillimeter band

We report on the development of low-noise quasi-optical SIS mixers for the frequency range 400-850 GHz. The mixers utilize twin-slot antennas, two-junction tuning circuits, and Nb-trilayer junctions. Fourier-transform spectrometry has been used to verify that the frequency response of the devices is well predicted by computer simulations. The 400-850 GHz frequency band can be covered with four separate fixed-tuned mixers. We measure uncorrected double-sideband receiver noise temperatures around 5hν/kB to 700 GHz, and better than 540 K at 808 GHz. These results are among the best reported to date for broadband heterodyne receivers

Medical Applications of MRC

Consistent powering is a limiting reagent for many medical implants and sensors. Powering in-vivo devices in animal studies requires either transcutaneous wiring (limiting mobility and increasing the chance of infection) or an implanted battery (limited lifetime and limits size of device). Wireless power transfer (WPT) would be able to overcome these challenges and permit the use of more advanced implantable devices in a research setting. Magnetic resonance coupling (MRC), an advanced form of inductive charging, allows good transfer efficiencies over significant air gaps, but works best a specific location and frequency, limiting mobility in animal studies. Using band-pass filter theory, an MRC system was simulated and optimized, as well as a design for a continuous WPT animal cage system utilizing MRC with 896 cm2. Both the frequency response and the actual power transfer of the systems were tested; downstream rectification circuitry was also developed to demonstrate WPT. Results indicate using multiple coils in series in a circle orthogonal to the individual coils produced a homogenous magnetic field and frequency response, and using passive coils increased coupling and efficient power transfer. While MRC is traditionally not a robust system, our results show the application can be extended charging over a wide range of space, allowing animal mobility and current experiments to be aided with electronic implants

Simulation and Visualisation of Functional Landscapes: Effects of the Water Resource Competition between Plants

A-07-30International audienceVegetation ecosystem simulation and visualisation are challenging topics involving multidisciplinary aspects. In this paper, we present a new generic frame for the simulation of natural phenomena through manageable and interacting models. It focuses on the functional growth of large vegetal ecosystems, showing coherence for scales ranging from the individual plant to communities and with a particular attention to the effects of water resource competition between plants. The proposed approach is based on a model of plant growth in interaction with the environmental conditions. These are deduced from the climatic data (light, temperature, rainfall) and a model of soil hydrological budget. A set of layers is used to store the water resources and to build the interfaces between the environmental data and landscape components: temperature, rain, light, altitude, lakes, plant positions, biomass, cycles, etc. At the plant level, the simulation is performed for each individual by a structural-functional growth model, interacting with the plant's environment. Temperature is spatialised, changing according to altitude, and thus locally controls plant growth speed. The competition for water is based on a soil hydrological model taking into account rainfalls, water runoff, absorption, diffusion, percolation in soil. So far, the incoming light radiation is not studied in detail and is supposed constant. However, competition for light between plants is directly taken into account in the plant growth model. In our implementation, we propose a simple architecture for such a simulator and a simulation scheme to synchronise the water resource updating (on a temporal basis) and the plant growth cycles (determined by the sum of daily temperatures). The visualisation techniques are based on sets of layers, allowing both morphological and functional landscape views and providing interesting tools for ecosystem management. The implementation of the proposed frame leads to encouraging results that are presented and illustrate simple academic cases

Scheduling Architectures for DiffServ Networks with Input Queuing Switches

ue to its simplicity and scalability, the differentiated services (DiffServ) model is expected to be widely deployed across wired and wireless networks. Though supporting DiffServ scheduling algorithms for output-queuing (OQ) switches have been widely studied, there are few DiffServ scheduling algorithms for input-queuing (IQ) switches in the literaure. In this paper, we propose two algorithms for scheduling DiffServ DiffServ networks with IQ switches: the dynamic DiffServ scheduling (DDS) algorithm and the hierarchical DiffServ scheduling (HDS) algorithm. The basic idea of DDS and HDS is to schedule EF and AF traffic According to Their minimum service rates with the reserved bandwidth and schedule AF and BE traffic fairly with the excess bandwidth. Both DDS and HDS find a maximal weight matching but in different ways. DDS employs a Centralized scheduling scheme. HDS features a hierarchical scheduling scheme That Consists of two levels of schedulers: the central scheduler and port schedulers. Using such a hierarchical scheme, the Implementation complexity and the amount of information needs to be Transmitted between input ports and the central scheduler for HDS are dramatically reduced Compared with DDS. Through simulations, we show That both DDS and HDS popup Guarantees a minimum bandwidth for EF and AF traffic, as well as fair bandwidth allocation for BE traffic. The delay and jitter performance of the DDS is close to That of PQWRR, an existing DiffServ supporting scheduling algorithm for OQ switches. The tradeoff of the simpler Implementation scheme of HDS is its slightly worse delay performance Compared with DDS

The perceived importance of sport management competencies by academics and practitioners in the cultural/industrial context of Taiwan

The study of management competencies and their application in the field of sport management has an established tradition. It is only relatively recently however that concern to consider the culturally specific context of competency evaluation has developed in the mainstream management literature and little work has been developed in the sport management field to address cultural specificity in respect of competencies. In addition the distinction between those competencies valued by sport management educators and by sport management practitioners is a relatively neglected topic. This study evaluates the perceptions of the critical competencies required of sport managers in Taiwan developing and applying a locally based tool for evaluation of competencies in sport management, and in particular evaluates the differences between the perceptions of sport management academics and practitioners in Taiwan. The results of this study highlight cultural differences between the Taiwanese and other cultural contexts in terms of the perceived importance of particular competencies, and have implications for sport management professional development and training

Magnesium isotopic composition of the oceanic mantle and oceanic Mg cycling

© The Author(s), 2017. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in Geochimica et Cosmochimica Acta 206 (2017): 151-165, doi:10.1016/j.gca.2017.02.016.To constrain the Mg isotopic composition of the oceanic mantle, investigate Mg isotope fractionation of abyssal peridotites during seafloor alteration, and assess Mg budget in the oceans, a suite of 32 abyssal peridotite samples from the Gakkel Ridge and Southwest Indian Ridge (SWIR) was, for the first time, selected for high-precision Mg isotope analyses. Although most of these samples are extensively altered, largely by serpentinization and weathering, primary olivine, diopside and enstatite grains are preserved in some samples. Olivine grains from the least altered samples have δ26Mg varying from −0.30 to −0.12‰ (n = 7), whereas enstatite and diopside have δ26Mg varying from −0.27 to −0.16‰ (n = 7), and from −0.23 to −0.09‰ (n = 6), respectively. Whole-rock δ26Mg values range from −0.24 to 0.03‰ with an average of −0.12 ± 0.13‰ (2SD, n = 32). Strongly serpentinized peridotites have lower average δ26Mg values (δ26Mg = −0.19 ± 0.07‰, 2SD, n = 7) than weathering-dominated ones (δ26Mg = −0.10 ± 0.12‰, 2SD, n = 25). Calculated Mg isotopic compositions of fresh mantle peridotites vary from −0.29 to −0.13‰, beyond the previously reported range of the subcontinental lithospheric mantle (−0.25 ± 0.04‰) and the analytical uncertainty (±0.07‰, 2SD). Our study therefore indicates that the oceanic mantle may have similar but slightly heterogeneous Mg isotopic compositions to that of subcontinental lithospheric mantle. Secondary serpentinization does not fractionate Mg isotopes of abyssal peridotites, whereas low-T weathering and formation of clay can result in the enrichment of heavy Mg isotopes in abyssal peridotites. This study also demonstrates that fluid-rock interaction does not necessarily produce rocks with intermediate Mg isotopic compositions. Magnesium isotopes of the rocks thereafter are dependent on the secondary minerals formed. We also conclude that the release of light Mg isotopes into the ocean during alteration of abyssal peridotites can be an important influx of Mg for the seawater Mg budget. Abyssal peridotites with a heavy Mg isotopic signature can be recycled into the mantle in subduction zones and may thus result in heterogeneous Mg isotopic compositions of the oceanic mantle and heavy Mg isotopic compositions of arc magmas.This study was supported by grants from the National Science Foundation of China (grants 41473038 and 41503010), China Postdoctoral Science Foundation (2015M570145), National Science Foundation (EAR-1056713 and EAR-1340160) and project MOST104 -2745-M-002-001-ASP granted to SLC. Partial support for HJBD was provided by the US National Science Foundation (OCE-1434452)

Meeting Potential New U.S. Climate Goals

We explore the performance of a potential addition to U.S. climate policy using authority under Section 115 of the Clean Air Act, with special attention to distributional effects among the states. This portion of the Act concerns trans-boundary air pollution, and under its provisions a national greenhouse target could be allocated among the states, with the details of state implementation optionally guided by a model rule as under other provisions of the Act. With trading allowed among the states, such a measure could lead to a national price on the covered gases. While we adopt features of a possible Section 115 implementation, the illustrative analysis is applicable to similar cap-and-trade programs that might be adopted under other authorities. We investigate the implications of such a policy using MIT’s U.S. Regional Energy Policy (USREP) model, with its electric sector replaced by the Renewable Energy Development System (ReEDS) model developed by the U.S. National Renewable Energy Laboratory. Existing federal and state climate policies are assumed to remain in place, and a national constraint on CO2 emissions is applied to achieve 45% or 50% reductions below the 2005 level by 2030. We apply the policies in a Baseline and a Low-Cost Baseline, the latter with more aggressive assumptions of technology cost improvements. The U.S. is aggregated to 18 individual states and 12 multi-state regions, and the effects of the national emissions restriction are investigated under three alternative methods by which the EPA might allocate these targets among the states. We find the cost of achieving either target to be modest - allowing for nearly identical economic growth, even without taking account of air quality and climate benefits. The alternative allocation methods generate varying per capita revenue outcomes among states and regions and drive most of the welfare impact through a direct income effect. It is assumed that states distribute permit revenue to their residents in equal lump-sum payments, which leads to net benefits to lower income households. Under the Low-Cost Baseline, carbon prices in 2030 are about ⅓ those in the Baseline, and the overall pre-benefit welfare effects are negligible. Considering climate benefits evaluated using the social cost of carbon and particulate matter air pollution health benefits, less the mitigation costs, we find net benefits in all cases, with slightly larger net benefits with the 50% reduction below 2005 emissions

Pengaruh Model Pembelajaran Think Pair Share dalam Sistem Pembelajaran Blended terhadap Higher Order Thinking Skills

Abstrak: Higher order thinking skills (HOTS) pada pebelajar terbentuk melaluimodel dan sistem pembelajaran. Model pembelajaran menggunakan think pair share (TPS) yang dikombinasikan dengan sistem pembelajaran blended (SPB).Quasy axperiment dengan model posttest only control group diberlakukan kepada mahasiswa jurusan Teknologi Pendidikan Universitas Negeri Malang angkatan 2015. Sampel sebanyak 44 mahasiswa yang dipilih secara random. Uji analisis data menggunakan uji independent sample t-test. Diperoleh nilai Sig. sebesar 0,678, yang berarti > 0,05 dengan rata-rata nilai posttest kelompok eksperimen sebesar 74,59 dan kelompok kontrol sebesar 76,64. Sehinggatidak terdapat perbedaan yang signifikan HOTS mahasiswa yang menggunakan dengan model pembelajaran TPS dalam SPB dan SPB tanpa model pembelajaran TPS. Abstract: Higher-order thinking skills (HOTS) for students are formed through learning models and systems. The learning model uses think pair share (TPS) combined with the blended learning system (SPB). Quasi-experiment with the posttest only control group model is applied to students of the Education Technology Department of the State University of Malang in 2015. The sample is 44 students randomly selected. Test data analysis using the independent sample t-test. Obtained Sig. amounting to 0.678, which means> 0.05 with the average posttest value of the experimental group at 74.59 and the control group at 76.64. So there is no significant difference in HOTS students using TPS learning models in SPB and SPB without TPS learning models