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A temperature sensor based on the combination of a temperature variable oscillator and a linear controlled oscillator is proposed, which can realize temperature detection through the characteristic of frequency changing with temperature. The changing frequency is generated by the two oscillators, and by adjusting the frequency linear change, the linearity of the sensor is also increased. Through the frequency digitizer, the digital signal can be output. Compensation through a process compensator improves the accuracy of the sensor after a single point correction. After conducting tests on 15 experimental samples, the accuracy was achieved within ± 1.2 ∘ C across the temperature range of 0 to 125 ∘ C, demonstrating a highly favorable level of precision. [ABSTRACT FROM AUTHOR]

To improve the controllability of the electric power output and the economic performance of a large-scale wind farm, an auxiliary energy storage system is required. This paper deals with the rule of planning reasonable energy storage power and capacity based on the historical annual mean wind speed data, the probability density of the pulsating wind power output, and the warranted firm power provided by the wind farm. Specifically, the evaluation index of the fluctuation degree of the firm power is defined in order to optimize the planned energy storage capacity. After that, the firm power escalation affected by the energy storage power and the conversion rate of the storage device are quantitatively evaluated. All of these analyses contribute in a significant way towards determining the acceptable energy conversion rate with the condition of limited energy storage space of a wind-storage hybrid power system. The proposed evaluation method of the firm power escalation is verified by MatLab simulation results. [ABSTRACT FROM AUTHOR]

Using 19-year satellite altimetric data, variations in the eddy kinetic energy, energy exchanges and interaction between the eddy field and mean flow are discussed for the Kuroshio south of Japan. In the seasonal cycle, the eddy kinetic energy level is a minimum in December/January and a maximum in April/May. In addition to seasonal variations, the eddy kinetic energy undergoes interannual changes. The energy transfers mainly from the mean flow to the eddy field in the Kuroshio south of Japan, and dominant energy exchanges mainly occur along the Kuroshio path south of Japan in each year from 1993 to 2011. In addition, there is often barotropic instability south of Honshu. Regarding interactions between the eddy field and mean flow, cyclonic and anticyclonic accelerations are also found along the Kuroshio path and they flank each other. There is cyclonic acceleration always imposed on southeast of Kyushu, and anticyclonic acceleration dominates south of Honshu from 2001 to mid-2005. Reynolds stress is used to explain the dynamic process of energy exchange. Furthermore, lag-correlation and linear regression analysis show that variability of the energy conversion rate and Reynolds stress involve responses to eddy acceleration at two time scales. The enhanced eddy acceleration induces large Reynolds stress, and enhanced Reynolds stress or barotropic instability further enforces energy transfer from the mean flow to the eddy field. [ABSTRACT FROM AUTHOR]

Cold-water corals rely on currents to transport food towards them and when external conditions are favourable, they can form coral mounds. These structures, which can be over 300 m high, influence the hydrodynamics around the reefs that grow on the mounds, which feeds back to affect coral- and therefore mound-growth. We investigated these feedbacks at the Logachev coral mound province, by running simulations with a 3D hydrodynamic model (Roms-Agrif), using different seafloor bathymetries that represent consecutive stages of mound development. Simulations ranged from a fully smoothened bathymetry without mounds, to a coral mound (Haas mound) at 1.5 times its current size. The effect of mound height on coral growth was investigated by looking at the baroclinic (internal) tide, turbulent energy dissipation, vertical velocities, and horizontal bottom currents. The simulations suggest that with increasing mound height horizontal velocities increase, while turbulent energy dissipation and vertical velocities around the mound foot decrease. This supposedly limits coral growth at the mound foot and hence lateral mound extension in later stages of development. An increase in turbulent energy dissipation and vertical velocities on the mound top and upper flanks, indicates vertical mound growth at all subsequent stages. Our findings of continued vertical mound growth provide an explanation for recently published data on benthic cover from a transect over Haas mound, that show a dominance of live corals on the mound top. We find areas of increased energy conversion rates from the barotropic (surface) to the baroclinic tide on the bathymetry where we artificially eliminated the mounds from (i.e. smoothened bathymetry). Interestingly, these areas overlap with the region where coral mounds are located at present. So, the baroclinic tide is likely an important mechanism in the process of coral mound establishment. Given the relative ease with which the energy conversion rate from the barotropic to the baroclinic tide can be deduced from hydrodynamic model simulations, our results provide opportunities to investigate where coral mounds may be initiated worldwide. [Display omitted] • We simulated hydrodynamics around different stages of coral mound development. • Simulations were analysed for benthic food supply proxies, e.g. vertical mixing. • Trapped baroclinic (internal) tides seem to be related to coral mound initiation. • Mounds affect benthic-pelagic coupling already when they are tens of meters tall. • Vertical food supply increases with mound height, with no limiting feedbacks. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogen and ethanol are promising biofuels and have great potential to become alternatives to fossil fuels. The influence of organic loading rates (OLRs) on the production of fermentative hydrogen and ethanol were investigated in a continuous stirred tank reactor (CSTR) from fermentation using molasses as substrate. Four OLRs were examined, ranging from 8 to 32 kg/m3·d. The H2 and ethanol production rate in CSTR initially increased with increasing OLR (from 8 to 24 kg/m3 d). The highest H2 production rate (12.4 mmol/h l) and ethanol production rate (20.27 mmol/h l) were obtained in CSTR both operated at OLR = 24 kg/m3 d. However, the H2 and ethanol production rate tended to decrease with an increase of OLR to 32 kg/m3 d. The liquid fermentation products were dominated by ethanol, accounting for 31–59% of total soluble metabolities. Linear regression results show that ethanol production rate (y) and H2 production rate (x) were proportionately correlated which can be expressed as y = 0.5431x + 1.6816 (r 2 = 0.7617). The total energy conversion rate based on the heat values of H2 and ethanol was calculated to assess the overall efficiency of energy conversion rate. The best energy conversion rate was 31.23 kJ/h l, occurred at OLR = 24 kg/m3 d. [Copyright &y& Elsevier]

• Droplet jumping induced by merging of a moving drop and a static one is studied. • The effect of initial velocity of the moving droplet is discussed. • The initial velocity accelerates droplet merging and changes droplet departure. • The initial velocity affects the energy conversion rate during jumping greatly. To explore the effect of initial velocity on the droplet jumping induced by coalescence of a moving droplet and a static one, we performed simulations using the volume of fluid method with a dynamic contact angle model, and validated the simulation results against our experiments. The results show that the initial velocity of the moving droplet accelerates the droplet deformation during jumping, resulting in a unique departure feature. Droplet departs at different stages under different initial velocities, and the droplet departure velocity in the vertical direction is approximately constant at the first stage and then increases after Reynolds number reaches a critical value. The horizontal departure velocity is proportional to the initial velocity with a ratio of 0.4. The initial velocity also affects the energy conversion during the droplet jumping greatly. This work shall bring new insights into the droplet jumping behavior and promote its application in related fields. [ABSTRACT FROM AUTHOR]

• Typical voltage and current waveforms of electrical disintegration are studied. • Peak current, electrical breakdown delay and power in the process of discharge were investigated. • Effect of thickness and breakdown voltage on energy conversion were investigated. The high-voltage electrical pulse coal fracturing technology based on the principle of electrical disintegration (ED) has been put forward, but the voltage and current waveform are rarely reported. In this study, effects of coal thickness and breakdown voltage on voltage and current waveforms in during ED in air environment were investigated. Besides, the changes of peak current, electric breakdown delay and instantaneous power with the variations of coal thickness and breakdown voltage were analyzed, and the changes of deposited energy and energy conversion rate with the variations of thickness and breakdown voltage were discussed. The results show that coal thickness and breakdown voltage have notable effects on deposited energy. Under the same breakdown voltage, the deposited energy inside coal samples with different thicknesses differs. In contrast, with the same coal thickness, the deposited energy in coal sample increases with the increase of breakdown voltage. The energy conversion rate increases first and then decreases with the increase of coal thickness, while it decreases first and then increases with the increase of voltage. Therefore, with certain coal thickness, there is an optimum breakdown voltage which enables the energy conversion efficiency to reach the optimal. [ABSTRACT FROM AUTHOR]