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Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Synthesis between the printed spiral coil and the planar interdigital capacitor for near-field wireless energy transfer (WET) is proposed. The proposed amalgamated design is intentionally positioned under several displacements, namely, planar offsets at the z-axis as well as lateral offsets at both the xand y-axes to investigate tolerance capability. This is particularly crucial in practical circumstances, whereby a perfect alignment between primary and secondary resonators is not usually achieved unless with the integration of magnet plates to aid seamless position latching, otherwise complex adaptive matching circuits are needed to compensate for displacements. At a fixed axial transfer distance of 25 mm, the corresponding maximum simulated and measured transfer efficiency is 73.01% and 71.84%, respectively, under perfect alignment. Sustainable power transfer efficiency (PTE) is demonstrated during a 360° planar clockwise rotation with the step size of 45° and the measured variation ratio is 0.02 while the feasibility of preserving PTE until 0.6 quotients of lateral displacement and axial distance is validated when up to 15-mm lateral offsets occur either from x or y reference planes. It can thus be concluded that the printed spiral resonator proposed appears to be a good candidate to rectify planar and lateral displacements featuring simplicity and space-saving robust structure that necessitates only a minimized footprint, thus paving the way for adaptation in WET applications, such as consumer electronics and implanted medical devices.

A printed spiral resonator without external lumped elements is proposed. Instead of employing surface-mount device capacitors, the series-parallel capacitive plates are designed and etched on the same substrate to achieve simultaneous conjugate matching between a pair of symmetrical near-field coupled resonators. Simulations are conducted with the aid of CST Microwave Studio. The proposed design displayed satisfactory tolerance toward planar displacement at z-axis plane, lateral displacement at x and y-axis planes, as well as concurrent planar and lateral displacement. Positioned at perfect alignment with a transfer distance of 15 mm, the simulated and measured maximum power transfer efficiency achieved are 79.54% and 74.96%, respectively. The variation ratio for planar displacement acquired is 0.29% when receiving resonator is rotated from -180° till 180° with a step size of 15°. Under rotational angle from 0° till 180°, the measured average variation ratio for lateral displacement at xand y-axis up to 15 mm is 20.14%. The feasibility of sustaining power transfer efficiency under various offsets depicts the possibility of integrating the proposed simple design for low power wireless energy transfer applications, such as wireless charging for handheld devices in consumer electronics and implanted biomedical devices.

A method to control the power distribution among receivers by the load values in a single-input, multiple-output (SIMO) wireless power transfer (WPT) system is investigated. We first derive the value of loads to maximize total efficiency. Next, a simple, but effective analytical formula of the load condition for the desired power distribution ratio is presented. The derived load solutions are simply given by system figure of merits and desired power ratios. The formula is validated with many numerical examples via electromagnetic simulations. We demonstrate that with the choice of loads from this simple formula, the power can be conveniently and accurately distributed among receivers for most practical requirements in SIMO WPT systems.

A mass-balanced Ecopath model presents a quantitative description of the trophic structure, flow of energy and trophic interaction among ecological groups of an ecosystem. The Ecopath with Ecosim (EwE) modeling program (Version 6.5) was used to develop a preliminary trophic model for a tropical freshwater reservoir. The total fish biomass was 6.245 t/km2 and the highest trophic level of the reservoir was 3.362 (for snakehead). The ecosystem is phytoplankton based because primary producers originated 68% and detritus originated 32% of the total flow from lower trophic level. The gross efficiency of the fishery was 0.004, suggesting the inefficiency of the system. The positive effect of phytoplankton and detritus on most of the other groups were evident from mixed trophic analysis while moderately higher ecotrophic efficiency (EE) of phytoplankton shows the ecosystem's potential bottom-up control. The competition for the same resources among different groups was also obvious. The ratio of primary production/respiration (1.969) suggests that the ecosystem is at the developing stage and utmost contemplation should be given to concerned human activities. The low value of relative ascendancy (30.13) and overhead (69.87) reveals the stability of the ecosystem and some degrees of maturity. It also predicts the presence of significant strength in reserve of the system to withstand or overcome any perturbation. However, ecologically sustainable resource management plans should be implemented to ensure the sustainability of this reservoir resources. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin University of Science & Technology is the property of Journal of Harbin University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bacterial transmission from contaminated surfaces via hand contact plays a critical role in disease spread. However, the fomite‐to‐finger transfer efficiency of microorganisms during multiple sequential surface contacts with and without gloves has not been formerly investigated. We measured the quantity of Escherichia coli on fingertips of participants after 1‐8 sequential contacts with inoculated plastic coupons with and without nitrile gloves. A Bayesian approach was used to develop a mechanistic model of pathogen accretion to examine finger loading as a function of the difference between E coli on surfaces and fingers. We used the model to determine the coefficient of transfer efficiency (λ), and influence of swabbing efficiency and finger area. Results showed that λ for bare skin was higher (49%, 95% CI = 32%‐72%) than for gloved hands (30%, CI = 17%‐49%). Microbial load tended toward a dynamic equilibrium after four and six contacts for gloved hands and bare skin, respectively. Individual differences between volunteers' hands had a negligible effect compared with use of gloves (P <.01). Gloves reduced loading by 4.7% (CI = −12%‐21%) over bare skin contacts, while 20% of participants accrued more microorganisms on gloved hands. This was due to poor fitting, which created a larger finger surface area than bare hands. [ABSTRACT FROM AUTHOR]

Copyright of Tobacco Science & Technology is the property of Tobacco Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Powder coating is an important process in the food industry, especially for snack foods such as potato chips, to create variety in food products. Electrostatic coating has been adopted in order to provide better transfer efficiency and lower the dust produced during coating. Studying the effect of electrode voltage on coating efficiency and evenness of baked potato chips using the developed electrostatic powder coating system was the main purpose of this research. Different types of NaCl (refined and table salts) were coated on baked potato chips at 0, 30, 40, 50, 60, and 70 kV. After coating with either refined or table salt, transfer efficiency, adhesion after coating, coating evenness and texture of samples were determined. Higher transfer efficiency, adhesion and coating evenness were observed when electrostatic coating was conducted at 30-50 kV. Most samples with higher transfer efficiency, adhesion and evenness were obtained after electrostatic coating. However, it did not significantly affect hardness of baked potato chips. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Enhancing farm income level is one of the main purpose of the Common Agricultural Policy (CAP). The ability to reach such a goal can be measured in terms of transfer efficiency, that is affected by the presence of distributive leakages through the agro-food system. The present work aims to shed light on the income distributional effects of the main forms of CAP subsidies in Italy over the period 2008–2014: single payment scheme, coupled payment and second pillar aids. To this aim, an Arellano–Bond linear dynamic panel-data estimation (based on a database provided by the Italian FADN) is performed. Results show that all the main types of CAP support have a significant income effect, even though some relevant differences occur between decoupled and coupled components of direct payments received by Italian farmers as a consequence of distributional leakages.

The electro-hydraulic servo pump control system (EHSPCS) is a volume control system that uses a permanent magnet synchronous motor (PMSM) with a fixed displacement pump to directly drive and control the hydraulic cylinder. The energy transmission law of the system is very complicated due to the transformation of electrical, mechanical and hydraulic energy as well as other energy fields, and qualitative analysis of the energy transfer efficiency is difficult. Energy transfer analysis of the EHSPCS under different working conditions and loads is proposed in this paper. First, the energy flow transfer mechanism was analyzed, and the mathematical and energy transfer models of the key components of the system were established to explore the energy characteristic state transition rule. Second, a power bond diagram model was built, its state equation and state matrix were deduced, and a system simulation model was built. Finally, combined with the EHSPCS experimental platform, simulation experiments were carried out on the dynamic position following and steady-state position holding conditions of the system, and the variation rules of the power of each energy characteristic state and the system energy transfer efficiency under different loads were obtained. The research results provide a foundation for the study of power matching and energy-saving mechanism of the EHSPCS.

Transfer efficiency is one of the most significant indexes of magnetic coupling wireless power transfer (MC-WPT) systems, which is severely affected by frequency splitting. In this paper, a novel method is proposed for MC-WPT systems to achieve the maximum transfer efficiency by introducing and controlling the circuit detuning factors while maintaining the operating frequency at constant. Firstly, the circuit model of tri-coil MC-WPT systems is established along with the derivation of some key concepts, including the transfer efficiency and circuit detuning factors. Then the analytical expressions of the optimal circuit detuning factors, maximum transfer efficiency and a comprehensive discriminant which could quickly and accurately determine the critical value for every system parameters are derived. Further, the physical interpretation of the maximum transfer efficiency is firstly elucidated from the perspective of energy flow: (1) when the system is in non-splitting region, the energy flow path of the maximum transfer efficiency is transmitter–relay–receiver; (2) when system is in splitting region, the energy flow path of the maximum transfer efficiency is directly from the transmitter to the receiver. Finally, simulation models and practical prototypes are designed to verify the theoretical results. The simulation and experimental results show that the proposed system can maintain an almost constant maximum transfer efficiency over a wide range of transfer distance. The derived discriminant is very useful for guiding the system design in the future, and the energy flow analysis method will be beneficial for maximizing the efficiency for multi-coil MC-WPT systems. [ABSTRACT FROM AUTHOR]

Gelatinous zooplankton (Cnidaria, Ctenophora, and Urochordata, namely, Thaliacea) are ubiquitous members of plankton communities linking primary production to higher trophic levels and the deep ocean by serving as food and transferring "jelly‐carbon" Key Points: Gelatinous zooplankton link primary production to higher trophic levels and the deep ocean by serving as food and transferring jelly‐CFrom global jelly‐C production (0.038 Pg C year−1) 59–72% reaches 500 m, 46–54% to 1,000 m, 43–48% to 2,000 m, 32–40% to 3,000 m, 25–33% to 4,500 mThe jelly‐C flux reaching the ocean interior is larger than anticipated for an important component of the global biological soft‐tissue pump [ABSTRACT FROM AUTHOR]

• Gloves are a major route of Acinetobacter transmission in clinical settings. • Acinetobacter can be transmitted from nitrile gloves to polypropylene plastic. • Only A baumannii transferred from gloves to fomites 3 minutes after inoculation. • Transfer efficiency of A baumannii was 0.1%-33%, 3 minutes after inoculation. Several observational studies suggest that gloves of health care workers are major routes of multidrug-resistant Acinetobacter baumannii transmission. However, limited experimental data are available assessing Acinetobacter transmission from gloves to environmental surfaces. This study determined whether A baumannii was easily transferred from nitrile gloves to polypropylene plastic compared with other gram-negative bacteria that cause health care–associated infections in laboratory-controlled experiments. Gloved fingerpad-to-fomite transfer efficiency was determined for drug-resistant and -sensitive strains of A baumannii, Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, and Pseudomonas aeruginosa. Only A baumannii transferred from gloves to fomites 3 minutes after the bacterial transfer event. Transfer efficiency of A baumannii was 0.1%-33% at that time point. Bacterial transfer from contaminated gloves to the hospital environment may be related to the type of contaminating bacteria, inoculated bacterial level, fomites, and glove materials. Therefore, it is important to need a comprehensive assessment of the transfer efficiency. A baumannii can transfer easily from nitrile gloves to fomite compared with other gram-negative bacteria that cause health care–associated infections. These findings support data from previous observational studies that gloves of health care workers can be major routes of A baumannii transmission in clinical settings. [ABSTRACT FROM AUTHOR]

This figure showed the improvement of the energy transfer efficiency of USM by designing new types of polyimide composite and surface texture. • The new polyimide composite as frictional materials of USM was designed. • USM with PI composites had higher energy transfer efficiency that that with PTFE composites. • Fabricating micro-dimples on the surface of PI composites can further improve the efficiency of USM. • Processing the same surface texture on the stator made a reverse effect on the transfer efficiency of USM. In order to improve the transfer efficiency of the travelling wave ultrasonic motor (TRUM), the advanced polyimide-based (PI) frictional materials with high friction coefficient and elastic modulus were designed and prepared by hot press sintering. The friction coefficient of PI composite sliding against phosphor bronze was investigated by a flat-on-flat pattern tribo-meter simulated the running conditions of the TRUM. Besides, the micro-dimples with diameter of 300 μm and area density of 7.06% were fabricated on the surface of PI composites by laser ablation. The friction coefficient of the textured PI interface further increased compared to the smooth PI or polytetrafluoroethylene (PTFE) interface. Therefore, the mechanical output torque, rotational speed and transfer efficiency of the TURM with new frictional materials and surface texture were correspondingly improved. The enhancement mechanisms were discussed by analyzing the changes in friction coefficient and contact sate of the tribo-pairs. [ABSTRACT FROM AUTHOR]

This paper is a thorough theoretical analysis of a two-coil wireless power transfer system (WPTS) configured in series with a focus on power optimization rather than maximizing transmission (link) efficiency. Different definitions of the system efficiency in the pertaining literature are distinguished and clarified. The frequency splitting phenomenon is precisely explained, and furthermore, the analytical solutions are derived based on analysis of the input impedance. The effects of this behavior on the power transfer to a load resistance are discussed. Various aspects of the power optimization problem are explored. In particular, for the case when the system is driven at the resonance frequency, (i) the explicit expression of the optimal coupling factor between the two coils for a given load, and (ii) the optimum power with respect to the load are provided. The impedance matching methods using different circuit topologies are analytically or numerically investigated, revealing that the drive frequency can be arbitrarily chosen and not necessarily equal to the resonance frequency. This provides more options for exciting the system apart from the resonance condition, without compromising the delivered power. A comparison between optimization techniques is given in terms of the coupling factor k , showing that the bi-conjugate matching with Π - networks results in the maximum generated power and the transducer power gain (i.e., defined by the ratio between the received power and the power available from the source), which reaches 80 % at k = 84.4 × 10 - 3 , for example. [ABSTRACT FROM AUTHOR]

Abstract Eutrophication is a leading cause of impairment of lentic water bodies throughout the world. To inhibit algal blooms and remove excess nutrients, a 10,000 m2 restoration project consisting of vegetation establishment and fish manipulation was conducted in the eutrophic bay of the Yantian Reservoir, southern China. Three Ecopath models were constructed to assess the recovery effects at an ecosystem level, and time series data were simulated to propose a fishery policy. During the restoration, 1) the redundant primary production flowing back to detritus decreased due to the increased predation of four stocked fish with different feeding habits; 2) the transfer efficiencies (TEs) through trophic levels increased due to the reinforced energy flows along the planktivorous, herbivorous, and molluscivorous food chains; 3) the groups that had the highest keystoneness shifted from carnivorous fish to invertivorous fish and omnivorous shrimp, indicating the shift of mixed trophic impacts from top-down to wasp-waist control; and 4) the changing indices of path length, flow fluxes, matter cycling, and network information showed that the restored system was more mature, developed, and organized than before. To sustain the long-term energy balance and functioning of the ecosystem, the maximum fishing yields (0.37–8.53 g/m2/year) were determined to maintain the relative biomass (close to 1) of stocked fish and wild tilapia by harvesting their annual production. Graphical abstract Unlabelled Image Highlights • Hydrophytic establishment limited the production/biomass of the plankton community. • Biomanipulation enhanced the energy flows along herbivorous/molluscivorous food chains. • The varying keystone groups indicated a shift in trophic control from top-down to wasp-waist. • The restored system was more mature, cycled, organized, and web-like than before. • A fishery policy was proposed to harvest the stocked fish at 0.27–6.53 g/m2/year. [ABSTRACT FROM AUTHOR]

This paper presents the conceptual design and characteristic analysis of a sliding-type superconducting wireless power transfer (SWPT) system prior to practical device development. Structural designs of sliding transformer, copper secondary, and high temperature superconducting primary are presented. A single-pancake racetrack coil assembly wound by ReBCO tapes is used as the primary winding. 12-mm-width ReBCO tapes with 700 A class critical current are introduced to wind the ReBCO primary operated at 50 Hz. The relations among the transfer power, transfer efficiency, air-gap distance, primary current, secondary load and primary turn number are investigated to clarify the SWPT behaviors under different operating conditions. Benefited from high critical current and nearly zero loss of ReBCO primary and elimination of high-frequency power conversion devices, the sliding-type SWPT scheme could be well expected to combine the advantages of high power, high efficiency, and compact device structure. [ABSTRACT FROM AUTHOR]

This study applies a multilayer coil technology that can compensate for a decrease in transfer efficiency due to a lateral misalignment in a practical 100 kHz-band wireless power transfer system and validates its effect on the efficiency of compensation. The effectiveness is investigated using coils fabricated with Litz wires. Three-turn rectangular assistant coils 22.4 × 45.3 mm2 in size were stacked on a five-turn circular primary coil with a diameter of 45.3 mm in a 2 × 1 array. Transfer efficiency between two such coils was measured by producing lateral misalignment, while maintaining the vertical distance between the Tx and Rx coils at 7 mm. The experimental results showed that the transfer efficiency was compensated by approximately 46.1%P maximum in a misalignment state of 30 mm, which corresponded to 67% of the maximum size of the coil, compared to the transfer efficiency of the structure, in which the multilayer coil was not applied. Furthermore, transfer efficiency was compensated by 37.6%P, even in an asymmetric system in which the multilayer structure was applied only to the Tx coil, thereby confirming an excellent multilayer coil technology effect on compensation for lateral misalignment in practical cases.

The sinking velocity (SV) of organic particles is a critical driver of carbon transport to the deep sea. Accurate determination of marine particle SV and their influencing factors is therefore a key to better understanding of biological carbon storage in the ocean. We used two different approaches to estimate average SVs of particles during a Southern Ocean spring bloom (North of South Georgia): optical backscatter sensors on gliders ("large", >50 μm diameter), and radioactive pairs (234Th–238U and 210Po-210Pb). Our results were complemented with time-of flight estimations of bulk SVs from deep sediment traps deployed at 1950 m. Bulk SVs increased consistently with depth from 15 ± 1 m d−1 at 10 m to 50 ± 10 m d−1 at the depth of export (Z p = 95 m) and from 96 ± 35 m d−1 at 150 m to 119 ± m d−1 at 450 m. Only the fastest particles, mainly comprised by faecal pellets (FPs) and diatom aggregates, survived remineralization and dominated carbon fluxes at deep depth. The SV variability at the base of the Euphotic Zone was studied in relation to the stage of the bloom by analysing three different moments of the spring diatom bloom in the region during the years 2012, 2013 and 2017. The export efficiency (ExpEff) , defined as the ratio POC flux exported below the Euphotic Zone to the satellite derived surface NPP, was also evaluated. It was found from the temporal series that ExpEff and SV vary throughout the diatom bloom as the community structure progresses. A good correlation between both variables was observed (ExpEff = (0.023 ± 0.006) SV , r = 0.82, p = 0.04). Showing that the variability in how efficiently the carbon flux is exported out of the Euphotic Zone can be explained by the SV at which the particles sink. Further investigations are required to analyse if this is a specific model of the functioning of the BCP during the diatom bloom in North South Georgia or if it can be extrapolated to other scenarios. • Bulk SV has been evaluated at North South Georgia, during COMICS I using three different methods with consistent results. • The average sinking velocity (SV) increased consistently with depth. • SV correlates with the export efficiency (r = 0.82, p = 0.04). • During the diatom bloom, SV act as a driver of how efficiently the carbon flux is exported into the Twilight Zone. [ABSTRACT FROM AUTHOR]

Here we used data from six BGC-floats deployed in the southeast Pacific and southwest Atlantic Oceans, within the Southern Ocean's Subtropical Zone, to assess the seasonality of particulate organic carbon production from phytoplankton (POC phyto) and estimate POC transfer efficiencies at 100 m below the euphotic zone (T_100). While small particles <100 μM dominated the mixed layer, large particles >100 μM comprised a significant fraction of POC phyto below the mixed layer in both areas, possibly due to a "shade flora" composed by large diatoms. POC phyto was highly seasonal with highest biomass accumulation in the Atlantic side for both small and large particles. In the Pacific, the seasonal change in small particle production ΔPOC phyto was ∼66 mg m−2 versus ∼54 mg m−2 from large particles. In the Atlantic, ΔPOC phyto was ∼852 mg m−2 for small particles versus ΔPOC phyto ∼ 262 mg m−2 for large particles. Monthly T_100s in the Pacific ranged from 76% to 92% with maximum efficiencies during the deepening of the mixed layer depth. In the Atlantic, T_100s ranged from 43% to 76% with two periods of high T_100s: the first coinciding with the decline of large particles from the "shade flora", and the second coinciding with the deepening of the mixed layer during elevated small particle production. • Large phytoplankton particles accumulated below the mixed layer at mid-latitudes • The Atlantic Subtropical Zone produced more particulate organic carbon than the Pacific • Particle transfer efficiency in the Pacific was 85%, with a monthly amplitude of 76–92% • Particle transfer efficiency in the Atlantic was 60%, with a monthly amplitude of 43–76% [ABSTRACT FROM AUTHOR]

Vertical particle fluxes of particulate organic carbon (POC), chlorophyll a (Chl a) and biogenic silica (bSi) were measured on the productive shelf of southern Africa, the Agulhas Bank (AB), in March 2019. Sinking particulate material in the form of aggregates is hypothesized to form the benthic nepheloid layer (BNL) which is a turbid layer found near the seabed. This layer is known to affect the spawning success of squid as it is linked to high turbidity which reduces visibility during mating. To determine the distribution of fluxes and particle composition in the AB, we collected water samples below the surface mixed layer ('export') and near the seabed ('bottom') using a Marine Snow Catcher. POC export fluxes were significantly higher inshore than offshore (mean ± SD: 944.6 ± 302.0 & 461.1 ± 162.1 mg POC m−2 d−1, respectively). There was no significant difference in the cross-shelf distribution of Chl a and bSi export fluxes, however the inshore fluxes of Chl a and bSi were higher than offshore, suggesting a link between export fluxes and sinking organic matter derived from the more productive inshore surface waters. All bottom fluxes were significantly higher inshore, suggesting the contribution of sinking organic particles and resuspended bottom sediments to inshore fluxes. POC export efficiency (ratio of exported POC flux relative to net primary production (NPP)) was higher on the AB (range: 0.58–9.56) compared to the global shelf seas ratio of 0.18 and not related to NPP, suggesting an export of standing stock of carbon biomass, likely produced before the cruise. Transfer efficiency (i.e., the amount of exported flux that reaches the bottom) was also high (max: 0.99, 1.0 and 33.04 for POC, Chl a and bSi, respectively) but did not show a clear spatial pattern. We observed a significant positive correlation between bottom turbidity (a proxy for BNL presence) and export POC flux, suggesting the possibility that sinking organic matter is contributing to BNL formation on the AB. [ABSTRACT FROM AUTHOR]

Most wearable intelligent biomedical sensors are battery-powered. The batteries are large and relatively heavy, adding to the volume of wearable sensors, especially when implanted. In addition, the batteries have limited capacity, requiring periodic charging, as well as a limited life, requiring potentially invasive replacement. This paper aims to design and implement a prototype energy harvesting technique based on wireless power transfer/magnetic resonator coupling (WPT/MRC) to overcome the battery power problem by supplying adequate power for a heart rate sensor. We optimized transfer power and efficiency at different distances between transmitter and receiver coils. The proposed MRC consists of three units: power, measurement, and monitoring. The power unit included transmitter and receiver coils. The measurement unit consisted of an Arduino Nano microcontroller, a heart rate sensor, and used the nRF24L01 wireless protocol. The experimental monitoring unit was supported by a laptop to monitor the heart rate measurement in real-time. Three coil topologies: spiral–spiral, spider–spider, and spiral–spider were implemented for testing. These topologies were examined to explore which would be the best for the application by providing the highest transfer power and efficiency. The spiral–spider topology achieved the highest transfer power and efficiency with 10 W at 87%, respectively over a 5 cm air gap between transmitter and receiver coils when a 200 Ω resistive load was considered. Whereas, the spider–spider topology accomplished 7 W and 93% transfer power and efficiency at the same airgap and resistive load. The proposed topologies were superior to previous studies in terms of transfer power, efficiency and distance.

Highlights • We proposed an adaptive frequency measurement method in the WPT system. • We employ direct pulse counting to record the pulse width of frequency signal. • The LC circuit is adaptively excited by a pulse exciter to generate damped oscillation. • We model four kinds of coils applied to pulse trains measurement. • The frequency measurement method is proved that it can improve transfer efficiency of WPT. Abstract Resonance frequency is a key factor for improving transfer efficiency in a Wireless Power Transfer (WPT) system which has a wide application because the wired media is eliminated. In this paper, an adaptive frequency measurement method is presented and the influence on the transfer efficiency in the WPT system is explored. The LC circuit is adaptively excited by a pulse exciter to generate damped oscillation. The frequency signal of LC circuit is shaped to a rectangle pulse before measurement. In the proposed digital frequency measurement, a direct pulse counting technique is employed in which the pulse width is computed with the counter pulse. The pulse counting is implemented by a constant time window for reducing measurement error in the resonance frequency signal. The frequency measuring method is demonstrated by an experimental study based on coupled magnetic resonances. The experimental results show that the WPT efficiency and the peak power when driven at real resonant frequency are about 2.1% and 2.3%, respectively, higher than that of theoretical values, which indicated a better performance of resonance frequency measurement. [ABSTRACT FROM AUTHOR]

The biological carbon pump exports carbon fixed by photosynthesis out of the surface ocean and transfers it to the deep, mostly in the form of sinking particles. Despite the importance of the pump in regulating the air‐sea CO2 balance, the magnitude of global carbon export remains unclear, as do its controlling mechanisms. A possible sinking flux of carbon to the mesopelagic zone may be via the mixed‐layer pump: a seasonal net detrainment of particulate organic carbon (POC)‐rich surface waters, caused by sequential deepening and shoaling of the mixed layer. In this study, we present a full year of daily small‐particle POC concentrations derived from glider optical backscatter data, to study export variability at the Porcupine Abyssal Plain (PAP) sustained observatory in the Northeast Atlantic. We observe a strong seasonality in small‐particle transfer efficiency, with a maximum in winter and early spring. By calculating daily POC export driven by mixed‐layer variations, we find that the mixed‐layer pump supplies an annual flux of at least 3.0 ± 0.9 g POC·m−2·year−1 to the mesopelagic zone, contributing between 5% and 25% of the total annual export flux and likely contributing to closing a gap in the mesopelagic carbon budget found by other studies. These are, to our best knowledge, the first high‐frequency observations of export variability over the course of a full year. Our results support the deployment of bio‐optical sensors on gliders to improve our understanding of the ocean carbon cycle on temporal scales from daily to annual. Key Points: Gliders captured a full annual cycle of high‐frequency POC variability over the upper mesopelagic zoneSmall‐particle transfer efficiency displayed a strong seasonality, peaking in winter and early springThe data indicate a significant annual carbon supply to the mesopelagic zone by small particles through the mixed‐layer pump [ABSTRACT FROM AUTHOR]

Enclosed seas are suitable for bivalve farming due to high primary production, which provides food sources. The impact of oyster farming on the biological productivity of lower trophic levels was evaluated in Hiroshima Bay. The area-weighted mean primary production in the estuary (northeastern bay; NB) was 1.1 to 2.1 times higher than that of the offshore area (southwestern bay; SB) in all four seasons. In contrast, the area-weighted mean secondary production by net zooplankton in the NB was lower than that of the SB, except in August. The area-weighted mean secondary production by oysters in the NB was 2.2 to 2.8 times higher than that of the SB in all four seasons, and exhibited a similar spatial pattern to that of the primary production. The primary production was more efficiently utilized and transferred to secondary producers in the SB (16.7% on average) than in the NB (9.4% on average). This study provides guidance for oyster farming in Japan. [ABSTRACT FROM AUTHOR]

Abstract As the largest freshwater estuary in the Laurentian Great Lakes, Green Bay, Lake Michigan (USA) is an important ecosystem presenting both challenges and opportunities for investigating changes in the face of multiple anthropogenic stressors. We collected new data from 2000 to 2007 to assess changes in lower food web interactions after establishment of invasive species (Bythotrephes longimanus and Morone americana in 1988 and Dreissena polymorpha in 1993) and nutrient reductions (1990s). Phytoplankton and zooplankton biomass and composition, as well as primary productivity and zooplankton community grazing rates, were determined along the previously well-studied trophic gradient from the shallow Lower bay to the stratified, open-water Middle bay. A clear trophic gradient still occurred during 2000–2007, with higher nutrients, phytoplankton and zooplankton in Lower bay compared to Middle bay. Phytoplankton abundance and cyanobacteria dominance increased significantly compared to earlier studies. However, integrated primary productivity did not change significantly at either Lower or Middle bay. Zooplankton standing stock decreased in Lower bay, driven primarily by reductions of bosminids, chydorids, and cyclopoid copepods, but did not change in Middle bay. Zooplankton community grazing rates did not change significantly, but shifts in magnitude and seasonality of net phytoplankton growth rates are consistent with increased phytoplankton standing stocks. Changes in zooplankton composition indicate increased predation by invertebrates and decreased fish predation. Shifts in both bottom-up and top-down factors have occurred, with Lower and Middle bay regions more eutrophic and similar to each other as a result of changes in this highly productive Great Lakes embayment. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Including forage legumes in dairy systems can help address increasing environmental/economic concerns about perennial ryegrass monoculture pastures. This work investigated the effect of substituting fresh‐cut grass with increasing quantities of fresh‐cut white clover (WC) on milk fatty acid (FA) profile and transfer efficiency of dietary linoleic (LA) and α‐linolenic (ALNA) acids to milk fat. Three groups of three crossbred dairy cows were used in a 3 × 3 crossover design. Dietary treatments were 0 g kg−1 WC + 600 g kg−1 grass, 200 g kg−1 WC + 400 g kg−1 grass, and 400 g kg−1 WC + 200 g kg−1 grass. All treatments were supplemented with 400 g kg−1 concentrates on a dry matter basis. Cows had a 19‐day adaptation period to the experimental diet before a 6‐day measurement period in individual tie stalls. RESULTS: Increasing dietary WC did not affect dry matter intake, milk yield or milk concentrations of fat, protein or lactose. Milk polyunsaturated FA concentrations (total n‐3, total n‐6, LA and ALNA) and transfer efficiency of LA and ALNA were increased with increasing dietary WC supply. CONCLUSION: Inclusion of WC in pastures may increase concentrations of nutritionally beneficial FA, without influencing milk yield and basic composition, but any implications on human health cannot be drawn. © 2018 The Authors. Journal of the Science of Food and Agriculture published by JohnWiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background Healthcare-associated infections (HAIs) affect millions of patients every year. Pathogen transmission via fomites and healthcare workers (HCWs) contribute to the persistence of HAIs in hospitals. A critical parameter needed to assess risk of environmental transmission is the pathogen transfer efficiency between fomites and fingers. Recent studies have shown that pathogen transfer is not symmetric. In this study,we evaluated how the commonly used assumption of symmetry in transfer efficiency changes the dynamics of pathogen movement between patients and rooms and the exposures to uncolonized patients. Methods We developed and analyzed a deterministic compartmental model of Acinetobacter baumannii describing the contact-mediated process among HCWs, patients, and the environment. We compared a system using measured asymmetrical transfer efficiency to 2 symmetrical transfer efficiency systems. Results Symmetric models consistently overestimated contamination levels on fomites and underestimated contamination on patients and HCWs compared to the asymmetrical model. The magnitudes of these miscalculations can exceed 100%. Regardless of the model, relative percent reductions in contamination declined after hand hygiene compliance reached approximately 60% in the large fomite scenario and 70% in the small fomite scenario. Conclusions This study demonstrates how healthcare facility-specific data can be used for decision-making processes. We show that the incorrect use of transfer efficiency data leads to biased effectiveness estimates for intervention strategies. More accurate exposure models are needed for more informed infection prevention strategies. [ABSTRACT FROM AUTHOR]

Time-series sediment traps were deployed in the subtropical oligotrophic northwestern Pacific (SONP) at three depths from August to September 2015 to better understand vertical flux of sinking particles. Sinking particles were collected at 5-day intervals over the sediment trap deployment period. The average total mass flux at water depths of 400 m, 690 m, and 1,710 m was 9.1, 4.4, and 4.1 mg m-2day-1, respectively. CaCO3 materials constituted 50 to 70% of sinking particles while in comparison particulate organic carbon (POC) constituted up to 20%. A synchronous variation of total mass flux was observed at the three depths, indicating that calcite-dominated particles sank from 400 to 1,710 m within a 5-day period. POC flux at these water depths was 2.4, 0.38, and 0.31 mg m-2day-1, respectively. Our results indicate low transfer efficiencies of 16% from 400 to 690 m and 13% for the 400 to 1,710 m depth range. The estimated transfer efficiencies were significantly lower than those observed at the K2 station in the northwest Pacific subarctic gyre, presumably because of a prevalence of pico-cyanobacteria in the SONP. Because cyanobacteria have a semi-permeable proteinaceous shell, they are more readily remineralized by bacteria than are siliceous phytoplankton in the northwest Pacific subarctic gyre. Continued surface water warming and expansion of the SONP will likely have a profound impact on ocean acidification in the northwest Pacific, possibly affecting the transfer efficiency of sinking POC to the deep-sea. [ABSTRACT FROM AUTHOR]

Ozone dissolution system design is important for meeting transfer efficiency (TE) goals. Large sidestream pump flow (L) and high venturi inlet pressure improves TE but increases operating cost. Ozone TE was examined at a 25 gpm (97-Lpm) pilot-scale sidestream system with (SSw-dg) and without (SSwo-dg) degas separation. Under constant ozone dose conditions, process operating parameters were varied including sidestream gas/liquid (G/L) ratio, venturi-inlet water pressure, venturi-outlet water pressure, feed gas pressure, and ozone gas concentration. Performance results included determination of TE, ozone exposure (CTHDT), and hydraulic detention time (THDT). Several design aspects of sidestream ozone systems were examined to improve mass transfer by using remixing devices, protecting ozone gas piping from corrosion, calculating sidestream ozone residual, and driving force for mass transfer. Moisture contamination of ozone supply lines may cause corrosion and/or decomposition of ozone gas that releases heat and destroys ozone. Ozone gas piping design is critical to prevent trapping water that might enter gas pipe during power outage or when units are offline. During plant operation below design flow, multiple constant speed pumps or variable speed pumps were evaluated to reduce overall operating costs. [ABSTRACT FROM AUTHOR]

For a traditional 2-coil system outputting constant voltage (CV), the transfer efficiency decreases drastically as transfer distance increases. To solve this problem, this essay proposes a 3-coil system which could achieve CV output and Zero Phase Angle (ZPA) conditions with specific parameter values. This 3-coil system could partly relief transfer efficiency fall at a long transfer distance, without any complicated controls. In order to achieve CV and ZPA condition, this essay devises the parameter values based on the decoupling 3-coil model, and a prototype is designed accordingly to verify these characteristics. With 10 cm transfer distance, output voltage deviation is 5.5% as the load varies from 12 Ω to 200 Ω, proving that the output voltage almost keeps constant with load change. Furthermore, with software simulation, a comparison experiment between the proposed 3-coil system and a Series-Inductor-Capacitor-Inductor (S-LCL) compensated 2-coil system is built to verify the efficiency improvement. The transfer distance change leads to the differentiation of voltage gain for both 2-coil and 3-coil systems. So, the input voltage for both systems and the compensated capacitor in receiver loop of the 3-coil system are manipulated for keeping 60 V output voltage on the 12 Ω load. With distance increasing from 10 cm to 20 cm, transfer efficiency varies from 92.61 to 48.9% for the 2-coil system, and from 92.89 to 84.26% for the 3-coil system, effectively proving the efficiency improvement. The experiment and simulation results prove the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Ultrasonic power transfer (UPT) is a promising method for wireless power transfer technology for low-power medical applications. Most portable or wearable medical devices are battery-powered. Batteries cannot be used for a long time and require periodic charging or replacement. UPT is a candidate technology for solving this problem. In this work, a 40-KHz ultrasound transducer was used to design a new prototype for supplying power to a wearable heart rate sensor for medical application. The implemented system consists of a power unit and heart rate measurement unit. The power unit includes an ultrasonic transmitter and receiver, rectifier, boost converter and super-capacitors. The heart rate measurement unit comprises measurement and monitoring circuits. UPT-based transfer power and efficiency were achieved using 1-, 4- and 8-Farad (F) super-capacitors. At 4 F, the system achieved 69.4% transfer efficiency and 0.318 mW power at 4 cm. In addition, 97% heart rate measurement accuracy was achieved relative to the benchmark device. The heart rate measurements were validated with statistical analysis. Our results show that this work outperforms previous works in terms of transfer power and efficiency with a 4-cm gap between the ultrasound transmitter and receiver.