Wireless power transfer is demonstrated mathematically and experimentally for M primary coils coupled to N secondary coils. Using multiple in parallel has advantages over a single coil. First, the reduced inductance of transmitting makes amplifier less sensitive component variations. Second, with receiving coils, delivery an individual receiver changes loads attached other By using 16 cm by 18 6 8 coil, going from 1:2 coupling 2:2 coupling, we show increase received 1.8 9.5 W, only small...

A 20 cm by transmitting coil is designed for an inductively-coupled power transfer system. The design a spiral, whose geometry optimized to ensure even magnetic field distribution. This guarantees uniform delivery regardless of recieving position. tested using Litz wire, switchmode amplifier, and 6 8 connected rectifier variable load. system achieves maximum efficiency 80.9% 11.8 W. At fixed load, the has coefficient variation 2.2% as coil's position varied on transmitter. In general, high...

In wireless power systems for charging battery-operated devices, the selection of component values guaranteeing certain desired performance characteristics can be a tedious trial-and-error process, either sweeping in circuit simulations or changing components by hand. This difficulty is compounded variable nature load resistance presented device under charge. brief considers specific system architecture, which an open-loop class-e inverter using series-parallel arrangement impedance...

The advancement of vital sign radar technology has proven to be a useful tool in assessing various physiological dynamics, including heartbeat and respiration. There remains several signal processing challenges this field, which include overcoming the nonlinearities harmonics that populate power spectrum. Respiration distort overwhelm measurement due large amplitude. A supervised machine learning algorithm, gamma filter, offers an efficient, calibration-free solution model time series given...

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> A method to determine various operating modes of a high-efficiency inductive wireless power transfer system which is capable supporting more than one receiver proposed. The three are <emphasis emphasistype="boldital">no-load</emphasis>, emphasistype="boldital">safe</emphasis>, and emphasistype="boldital">fault</emphasis> modes. detection scheme probes the transmitter circuitry periodically mode....

Wheat (Triticum aestivum L.) crops in the inland Pacific Northwest demand nitrogen (N) fertilizers at high levels to achieve yield and grain protein objectives. Inefficiencies N use can accelerate soil acidification, contribute N2O emissions, result unnecessary input costs. Reducing losses is a complicated problem, as producers have consider targets, co-limitations of water other nutrients, longer term health goals, variability crop performance across fields. However, past work region has...

A wireless power system via magnetic induction that can deliver 32 W to a laptop is designed and fabricated. 60% peak end-to-end regulated efficiency achieved. load detection scheme also implemented, which detects when device placed on the transmitter shut down if faults are detected. The eliminates need plug into AC running or charging.

A new type of dual-function structure is presented, a 3-D fractal heatsink antenna. This design simulated at different iterations in Ansoft HFSS and ePhysics to assess its electromagnetic thermal performance, relative patch antenna finned It compares favorably antenna, improving radiation efficiency (up 0.98) directivity 8.21 dB). As heatsink, it decreases resistance comparison typical by an order magnitude.

Wireless power transfer systems using near-field magnetic coupling are attractive as they allow with high efficiency and do not require an unobstructed path between transmitter receiver. In this work a two coil wireless transmission system is analyzed, including the driving amplifier, demonstration built characterized. The achieves 76% for distance of 1 meter 40 W transferred power. effects changes to geometry (pitch angle coils, separation distance) also examined, effect on amplifier...

Bulk electrical conductivity (σ a ) can dominate the low frequency dielectric loss spectrum in soils, causing changes permittivity and errors estimated water content. We examined dependence of measured apparent ( K on σ contrasting soils using time‐domain reflectometry (TDR), digital transmission (TDT) sensor, capacitance sensor (5TE) during near saturated solute displacement experiments. Sensors were installed columns packed with fine sand or clay loam soil. Displacement experiments...

Knowledge of crop abiotic and biotic stress is important for optimal irrigation management. While spectral reflectance infrared thermometry provide a means to quantify remotely, these measurements can be cumbersome. Computer vision offers an inexpensive way remotely detect independent vegetation cover. This paper presents technique using computer disease in wheat. Digital images differentially stressed wheat were segmented into soil pixels expectation maximization (EM). In the first season,...

A Soil Vegetation Atmosphere Transfer (SVAT) model, viz. Land Surface Process (LSP) is coupled with a widely used crop‐growth DSSAT, to estimate energy and moisture fluxes at the land surface in vadose zone for growing vegetation. In this study, we present detailed observations of soil crop characteristics, various components water balance during season‐long field experiment sweet corn. The data set calibrate LSP Latin Hypercube Sampling Pareto ranking. We compare model estimates growth...

Time domain reflectometry (TDR) is an established method for the determination of apparent dielectric permittivity and water content in soils. Using current waveform interpretation procedures, signal attenuation variation media properties along transmission line can significantly increase sampling error estimating time, t 2 , at which pulse arrives end probe. Additionally, manual adjustment analysis parameters frequently required software to accommodate changes when processing large time...

Dryland agriculture in the Inland Pacific Northwest is challenged part by rising input costs for seed, fertilizer, and agrichemicals; threats to water quality soil health, including erosion, organic matter decline, acidification, compaction, nutrient imbalances; lack of cropping system diversity; herbicide resistance; air concerns from atmospheric emissions particulate greenhouse gases. Technological advances such as rapid data acquisition, artificial intelligence, cloud computing, robotics...

Current production of sweet corn ( Zea mays L.) in the United States is 4.0 million Mg with a value $807 million. The fresh market component amounts to three-fourths this California, Florida, and Georgia harvesting half U.S. production. Existing maize simulation models have limited potential assist as result distinctive nature marketed end product (i.e., ears versus dry mature kernels). purpose study was develop model. Cropping System Model-Crop-Environment Resource Synthesis CSM-CERES-Maize...

A high-efficiency wireless power transfer system which is capable of supporting more than one receiver using class E operation for transmitter via inductive coupling has been designed and fabricated. The design approach the also presented in this paper. requires no complex external control but relies on its natural impedance response to achieve desired delivery profile across a wide range load resistances while maintaining high efficiency prevent any heating issues. switch circuit used...

Soil water measurement is important in management for irrigation and hydrologic sciences. The purpose of this paper to develop test the design a cylindrical access-tube mounted waveguide use time-domain reflectometry (TDR) situ soil content sensing. Several prototypes with varying geometrical parameters were constructed. sensors compared by evaluating characteristics reflected waveforms from (200-ps) step pulse different media, including air, triethylene glycol, deionized water, over range...

Highlights Long-term site-specific multiple-crop yield data is used in two modeling approaches. Different sources of data, including soil properties, topography, weather, and multispectral are tested. Linear Bayesian hierarchical (BHM) evaluated by examining predictions relative yield. BHM with spatio-temporal effects provides the best estimates, handles missing uncertainty estimates time space. Abstract. Growers inland Pacific Northwest face numerous challenges managing cropping systems....

Abstract Soil wet aggregate stability is widely measured for soil health ratings, and two mobile applications have been recently developed that provide simple fast measurements of on three pea‐sized aggregates. However, techniques are needed to scale the test make it practical studies with large sample numbers. Here, we describe an approach measure 10‐min slaking index 20–36 aggregates simultaneously using a multi‐well plate automated image analysis. We used this 160 samples (2120...

Highlights Continuous no-tillage with fertilizer deep-banded below the seed can result in stratified soil acidity that cannot be rapidly addressed surface-applied lime. We modified a tractor-driven sweep implement to inject fluid lime targets sub-surface minimal disturbance maintains surface crop residues, and tested it prior seeding winter peas at 4 liming rates. Soil chemistry, microbiology, growth were monitored over season. Abstract. Deep-banding ammonia urea-based nitrogen fertilizers...

Soil water measurement is important in management for irrigation and hydrologic sciences. The purpose of this paper to describe the design a cylindrical access-tube mounted waveguide use time-domain reflectometry (TDR) in-situ soil content sensing. In order optimize with respect sampling volume losses, we derived electromagnetic fields produced by TDR sensor geometry. Using analytical derivation, effects on area, waveform shape, losses while varying were examined. It was found that when tube...

Stored water, i.e., soil moisture in the root zone, is most important factor governing energy and fluxesat land surface. Crop models are typically used to estimate these fluxes simulate crop growth development.Remotely sensed microwave observations can be improve estimates of fluxes, biomass, yield. This researchaims calibrate a model, CERES-Maize, for growing season corn north-central Florida. TheCERES-Maize model was extended weather conditions region calibrated using data from our...