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The development of electricity generation from renewable sources, particularly photovoltaic energy (PV), as well as the significant growth of electric mobility with electric vehicles (EVs), leads us to contemplate the potential impacts of these components may have on an existing distribution electrical network. An electrical distribution network is designed to supply electrical loads in one specific direction while maintaining the quality of its technical parameters, such as current, voltage, and frequency. In this article, through a literature review, we will explore how the integration of each component, photovoltaic energy, and electric vehicles, individually and in combination, can impact the electrical distribution network. In addition, we will examine based on a literature review, the methods proposed by various authors to enhance the impacts occurring on the network due to this integration. [ABSTRACT FROM AUTHOR]

The flow slab design is an important factor in the Proton Exchange Membrane Fuel Cells (PEMFCs) because of its significant impact on the system performance along with the manufacturing cost, as crucial for commercial applications. Therefore, the flow slab with a low-pressure drop, high uniformity, and excellent power performance is a topic of concern. In this study, a new biometric flow slab with an elbow and baffle is designed and compared with the conventional flow slabs under a series of studied cases. The results show that the power performance of the biometric flow slab is better than the conventional types of flow slabs. Here, the power density of 6182.43 W/m2 is obtained by the new biometric type of BFS2 and up to 37.36% of ratio to the type of parallel flow slab. That is to say, the new type of biometric flow slab has effectively avoided the sharp drops issue of the power density appearing in the type of parallel flow slab. Similarly, a lower pressure drop in the biometric type has been observed when compared to the serpentine flow slab. The results have also indicated a positive correlation between the oxygen diffusion flux and the current density distribution. It has also been observed that the more uniform oxygen diffusion flux distribution was supported, the more uniform current density distribution was obtained. The net power performance of the biometric flow slab at a working V cell = 0.4 V has been increased up to 36.98% when compared to the parallel flow slab. Finally, the new type of biometric flow slab BFS2 seemed to be the better choice for its significant overall performance because of the reduced power loss and certified flow visualization. These findings could be useful for the improvement of the flow field design in PEMFC when applied in commercialization in the future. • Biometric flow slab is better than the conventional flow slabs. • 6182.43 W/m2 and 37.36% of ratios to parallel type are obtained by biometric SFS2. • Biometric SFS2 shows its significant overall performance. [ABSTRACT FROM AUTHOR]

The present study is aimed at putting forward a novel temperature controller (including software and hardware) for a fan-and-damper refrigerator considering the electric current drawn by the single-speed compressor as the process variable. The control algorithm consists in a dynamic reference modification of a PI controller, together with a set of empirical conjectures. In addition, a purpose-built electronic board was designed and prototyped. All experiments were performed in-house with the refrigerator placed in a climate chamber. The refrigerator was tested at two different surrounding air temperatures (16 and 25 °C) under pulldown, defrost recovery, and variable ambient temperature regimes. It was noted that the proposed controller was able to maintain the refrigerator temperature within ±1 °C tolerance bounds – figures like those obtained for the baseline thermistor-based temperature controller – albeit being less costly. [ABSTRACT FROM AUTHOR]

The current study investigated the simultaneous impacts of dust as well as other environmental parameters on cell temperature and the electrical outputs of photovoltaic systems. Based on the experimental and analytical analysis, several linear and polynomial semi-empirical correlation forms were proposed. It was shown that cell temperature depends directly on irradiation and ambient temperature, as well as inversely on humidity, wind speed, and the amount of accumulated dust on the surface. During the four-year outdoor experiments and further indoor measurements, the surface dust density varied from 0 to 10.1174 g.m−2, which resulted in up to a 28 % current loss. Although, it was shown that dust affects the output voltage less, and the most recorded variation was <0.5 % reduction. The electrical behavior of the photovoltaic system was also simulated with a modified single-diode model. Comparing the simulation results, correlation predictions, and experimental measurements confirmed consistency. Moreover, it was shown that considering the prediction precision, simplicity, and computational cost, the proposed correlation forms should be preferred when just the output current, voltage, and power are of concern. The proposed modified semi-empirical correlation forms can be easily coupled with other models to improve their precision and accuracy. • Experimental investigation of parameters affecting a photovoltaic cell temperature. • Provide a semi-empirical correlation form to predict cell temperature. • Provide semi-empirical correlation forms to predict output current and voltage. • Provide semi-empirical correlation forms to predict output power. • Increase precision and reduce computational costs for predicting output behavior. [ABSTRACT FROM AUTHOR]

Metallic materials are widely used in many applications of mechanical and aerospace engineering. Due to severe environmental and loading conditions, components and structures can experience cracking phenomena. In this regard, different non-destructive techniques were developed in the last years to detect and monitor cracks that can propagate during the actual loading conditions. This work deals with the application of the conduction thermography as a non-destructive technique for the offline control and inspection of different notched metallic specimens characterized by short fatigue cracks. The potentials of the technique have been demonstrated considering a low-cost set-up consisting of a power supply of low current and limited voltage, and a microbolometer sensor. Moreover, to further simplify the inspection, the specimens were not black coated. Quantitative results, in terms of crack lengths, have been obtained using a new procedure of data analysis and then compared to those provided by thermoelastic stress analysis, a well-established technique adopted for the detection and monitoring of cracks. [ABSTRACT FROM AUTHOR]

The electrical wire fire often occurs in the confined space, making the flame spread behavior complex and the risk increase. In this paper, experimental and theoretical study on the flame spread over three types of polyethylene (PE) electrical wires under different side-confined distances (0∼40 mm) and currents (0∼60 A) was carried out.The ratios of copper diameter to entire wire diameter were 6mm/10 mm, 8mm/12 mm, and 6mm/12 mm for type I, type II and type III, respectively. The results show that, with the increase of s, the flame width and height, and flame spread rate will firstly increase to the maximum peaks at the position of s = 5 mm with attachment wall effect, and then gradually decrease to the values of the unconfined conditions. And with the increase of current, these parameters will gradually increase to the largest at I = 40 A and then decrease for I = 60 A, as the current effect changes from preheating to dripping acceleration.The firm correlation between preheating length δ p h and pressure difference Δ P is built, which demonstrates the smallest preheating length is at s = 5 mm with the maximum promotion of heat transfer by gypsum board. On the other hand, the generated Joule heat by the current will enhance the length of preheating, making it proportional to current. Meanwhile, it is found that, the dripping frequency influenced by the dripping mass rate, will increase with the current. The heat transfer components including of the solid conduction heat flux ( q ˙ j o u l e ″ and q ˙ c ″), flame heat flux ( q ˙ ν f ″ and q ˙ r f ″) and gypsum board heat flux ( q ˙ r g ″ and q ˙ ν g ″) are quantitatively analyzed. Correspondingly, a heat transfer model over flame spread is established, which can well predict the flame spread rate.As the diameter of the wire is relatively small, the controlling heat transfer is the flame convective heat flux q ˙ ν f ″ in this research. In addition, it is illustrated that, the heat flux of gypsum board q ˙ ν g ″ + q ˙ r g ″ will decrease with the increase of copper core diameter from type I of 6 mm to type II of 8 mm.While the solid conduction heat flux of copper q ˙ c ″ + q ˙ j o u l e ″ will decrease with the increase of thickness of PE from type I of 2 mm to type III of 3 mm. These findings can well give the understanding of heat transfer of flame spread over electrical wires with the effects of sidewall and current. [ABSTRACT FROM AUTHOR]

The Bohai Sea is the receiving basin of the Yellow River (Huanghe), one of the largest contributors of global terrestrial materials to the sea. An area of fine-grained sediment deposition extends northeast of the Yellow River and its formation mechanism is still unclear. A calibrated, high-resolution coupled model of the Bohai and Yellow Seas was used to investigate sediment transport pathways in the region under the influence of strong and varying winds in winter. Numerical results highlight the importance of storm events in modifying the regional sediment resuspension and transport. During winter, the prevailing winds are typically from the northeast and northwest, interspersed by relaxation periods with weak winds. Winds influenced the currents and sediment movement in the Bohai Sea through several processes: local wind waves and resuspension, coastal-trapped waves in the Bohai Sea, and remotely forced coastal-trapped waves in the Yellow Sea. During northwesterly winds, sediment off the Yellow River Delta was mainly transported eastward along the south coast of Bohai Sea and escaped the Bohai Sea through the southern Bohai Strait. When northeasterly winds prevailed, sediment transport split into three branches: westward into the Bohai Bay, northeastward to the central Bohai Sea, and eastward along the south coast of Bohai Sea. Modeling results driven by synoptic winds indicate a more complex sediment transport pattern than previously understood with monthly average wind forcing. These findings challenge the traditional view of predominantly eastward sediment transport during winter and help to explain the observed grain size distribution in the Bohai Sea, in particular the accumulation of fine-grained sediments northeast of the Yellow River. • Storms are important in modifying the regional sediment resuspension and transport. • Sediment movement in BS depends on local winds, its related CTWs and CTWs in YS. • The formation of muddy areas northeast of the YRD is related to the varied winds. [ABSTRACT FROM AUTHOR]

Aluminum 5454 alloys are considered a subject in this research, widely used in the industry, to develop die tools, molds, engine blocks, aircraft structural components, and many other commercial products. In this research, the WEDM process parameters effects on the Aluminum 5454 alloy tapered workpiece have been investigated. Tapered workpieces with angles of 30°, 45° and 60° are prepared, in which slots are generated using the WEDM process. The taper angle, peak discharge current and pulse-off time are selected as the controllable parameters in this research. Whereas other parameters are kept constant. Impact of the parameters over; kerf width, surface finish, MRR and wire have been investigated. ANOVA is applied to statistically analyze the influence of the factors over the four variables. Regression models for the four variables are determined and the Genetic Algorithm is applied to determine the feasible WEDM process parameters for the desirable magnitudes of the four variables. The regression models and optimized parameter values for different taper angles workpieces of Aluminum 5454 alloy can be used in the industry to increase the productivity and enhanced results. [ABSTRACT FROM AUTHOR]

Protections are suggested on the basis of a current relay with two capacitors and a reed switch, which is mounted at a safe distance from a busbar inside the busduct enclosure. The relay does not need in current transformers thus saving copper, steel, and insulating materials. It differs from reed switch based analogs in the noise immunity due to signaling after two actuations of the reed switch; non-operation in the case of sealing (due to the control of duration of breaker contact); the presence of a reed switch fastening structure, and built-in test diagnostics by mean of current supply into the reed switch winding. A technique for selecting protection parameters and assessing their sensitivity is presented. The inductions of magnetic fields which affect the reed switch are calculated with the use of the simplest formulas for the shielding coefficient and of the Bio–Savart–Laplace law, where experimentally derived correcting coefficients are introduced. Examples of the calculation of the induction of protection operation and of reed switch selection are presented along with an oscillogram which confirms the cutoff operability and speed. [ABSTRACT FROM AUTHOR]

This study examined the effects of constant current electrical stimulation (CCES) compared to constant voltage electrical stimulation (CVES), when applied within the same beef carcass (n = 79), on longissimus thoracis et lumborum (LTL) quality and palatability. There was a stimulation method × time interaction for pH, with CCES reducing the 3 h post-mortem pH, but increasing the 72 h post-mortem pH compared to CVES (P < 0.001). The CCES decreased the meat subjective Japanese Meat Grading Agency (JMGA) colour scores (P < 0.05) and increased the objective L ⁎ (P < 0.01), a ⁎ (P < 0.05) and b ⁎ (P < 0.05) colour values at 3 d post-mortem and L ⁎ and b ⁎ values (P < 0.05) during retail display compared to CVES, although the objective values from both stimulation methods were above established consumer acceptability thresholds. Additionally, CCES reduced the purge (P < 0.05) and drip (P < 0.01) losses, and tended to reduce shear force values (P = 0.089) compared to CVES, although these did not translate into differences in juiciness or tenderness evaluated by trained panelists (P > 0.1). Regarding flavour, the CCES meat had greater bloody/serumy flavour (P < 0.05) and corn aroma (P < 0.05), less unidentified aroma (P < 0.05), and tended to have greater corn flavour (P = 0.077) and less barnyard aroma (P = 0.079) than CVES meat. There were also increased concentrations of flavour-related volatile compounds including 2-methyl-butanal, 3-methyl-butanal and 2–5-dimethyl pyrazine levels (P < 0.05) with CCES. Overall, the CCES system slightly improved meat quality and flavour compared to CVES when applied to the same beef carcasses. Further consumer studies would be warranted to determine whether these differences translate into more acceptable meat. • Constant current vs constant voltage electrical stimulation (CC/CVES) were compared. • CCES hastened carcass side pH decline compared to CVES applied to the other side. • CCES meat had improved colour and less drip and purge losses than CVES meat. • CCES improved the meat flavour profile compared to CVES. • The CCES system was more effective for improving meat quality and flavour than CVES. [ABSTRACT FROM AUTHOR]

The impact of radiation on Si-based detectors garnered interest due to the observed degradation in their stability in high-radiation environments. In this study, we examined the effects of 3 MeV proton irradiation on both undoped and Al-doped n -Si diodes using I–V technique. The results revealed a decline in current trends for both types of diodes post-irradiation. This decrease was attributed to defects created by proton irradiation, which acted as recombination or trapping centres. However, the Al-doped n -Si diodes experienced a lesser decline in measured current, hinting at the radiation suppression effect of Al doping in Si. Additionally, Al-doped n -Si diodes displayed minimal changes in their diode parameters after irradiation, and their conduction mechanism remained unchanged. These results suggested that Al-doped n -Si diodes had superior stability compared to their undoped counterparts, implying that the presence of Al enhanced the diodes' resistance to radiation. The radiation suppression effect of Al seemed to stem from its ability to produce defects that improve Si's radiation-hardness, thereby mitigating the introduction of additional instability-causing defects during proton irradiation. Thus, incorporating Al was recommended for research aiming to improve the radiation resistance of Si. • Study explores 3 MeV proton impact on undoped and Al-doped n -Si diodes using I–V techniques. • Al-doped n -Si diodes show radiation suppression, with less current decline and minimal parameter changes after irradiation. • Al-doped n -Si diodes enhance Si-based detector radiation resistance by introducing stable defects through Al doping. [ABSTRACT FROM AUTHOR]

• "White Structure Flaking" (WSF) is an early subsurface type of spalling. • Conducting fatigue life tests for hydrogen-charged bearings. • The critical threshold for inducing WSF is 1 ppm. "White Structure Flaking" (WSF) is an early subsurface type of spalling that often occurs in bearings of automotive components. The investigation into WSF in automotive generator bearings involves analyzing returned failure bearings as well as conducting fatigue life tests for hydrogen-charged bearings. Through various analytical methods, it has been ascertained that the degradation of the surface lubrication state caused by electric current and frequent acceleration or deceleration is the primary factor leading to the generation of hydrogen from the grease, consequentially resulting in the formation of WSF. The study examined the occurrence time of WSF in hydrogen-charged bearings through fatigue testing, and the hydrogen critical threshold for inducing WSF is 1 ppm. Generally, as the hydrogen content rises, WSF is more likely to occur earlier. However, if the hydrogen content exceeds 1.5 ppm, the occurrence time does not increase rapidly with an increase in hydrogen content. [ABSTRACT FROM AUTHOR]

The ocean dynamics of the marginal seas in the Java-Makassar-Flores (JMF) Triangle seas facilitates the seasonal exchange of water masses between Java, Makassar, and Flores, which influences the occurrence of small pelagic fish. This research investigates seasonal fluctuations in sea currents, seawater temperature, salinity, and phytoplankton primary production (PPN and PPD) based on validated model output datasets from NEMO and PISCES from the INDESO simulation (2008–2015). The model demonstrated seasonal exchanges of the top 50 m of water masses in the area, where the eastward monsoon current transported freshwater (salinity<31 psμ) from the Java Sea to southern Makassar and Flores. This northwest monsoon produced a much fresher water in the southern region of Makassar and western region of Flores. During the southeast monsoon, the surface component of the Makassar throughflow, which transports saline water (salinity >34 PSU) into the Java Sea, pushes fresh Java waters westward. Seasonal salinity changes and PPN/PPD in the shelf region of southern Kalimantan correlated with substantial small pelagic fishing. • Ocean circulation and water mass exchange in the JMF seas were investigated using physical and biogeochemical ocean model. • Exchange of fresh Java and salty ITF waters are driven by monsoon current and ITF Makassar, creating strong salinity front. • The seasonal shifting of salinity front is a proxy for potential fishing grounds of small pelagic fishes in the JMF seas. [ABSTRACT FROM AUTHOR]

Recently, there has been a notable rise in social and scientific interest regarding microplastic pollution in coasts where waves significantly influence flow patterns and material transport. This study explores typical short-term movement of buoyant microplastics driven by surf zone processes including wave transformation, breaking, and orbital motion. To track microplastics, Lagrangian Particle Tracking Model (PTM) coupled with Eulerian wave-current interaction model appropriate for coastal hydrodynamics was used. From the simulations, several important findings were observed. (i) In alongshore uniform beaches, lighter and larger buoyant microplastics tended to reach beach more readily. (ii) Accurate predictions of microplastic transport in the surf zone required the consideration of wave breaking. (iii) In alongshore non-uniform coastal bathymetry, rip-currents can send buoyant microplastics offshore, beyond the surf zone. • In uniform beach, lighter and larger buoyant microplastics tend to reach beach. • Wave breaking delays onshore movement of buoyant microplastic particles. • Rip-currents send buoyant microplastics offshore, beyond surf zone. • A buoyant microplastic transport model tailored for coastal area is presented. [ABSTRACT FROM AUTHOR]

The current study tries a new approach to simulating interactions between waves and seagrass through Smoothed Particle Hydrodynamics (SPH). In this model, the plants are defined as a solid that respects Hooke's law, and are assumed to have direct interaction with the fluid. Given the characteristics of the SPH method, especially in terms of computational time, the dimensions of the simulations were limited. The first goal of the current study was to optimize the approach to avoid reaching certain limits such as the rupture of the simulated plant. Plant movements under waves and/or currents have been studied by several authors in various in-situ , physical, and numerical experiments concerning various vegetation species, thus proving that plant movements can be successfully reproduced by SPH 2D/3D. Manning's roughness coefficient, n , was calculated to confirm that the results were in accordance with what had been measured in flume studies. Even though there is still room for improvement, it is shown that this method can be used to estimate Manning's coefficient for coastal vegetation (seagrass and saltmarsh vegetation) and to greatly improve the modeling and forecasting of coastal erosion and storm surge risks by including the effects of vegetation in integrated models. • A fluid-structure interaction (FSI) in an SPH 2D/3D code was build. • This FSI code was tested and calibrated for a classical test. • This approach was tested on sea grass movement under currents or waves. • The simulations were compared with experimental and field measurements. [ABSTRACT FROM AUTHOR]

Sediment incipient motion is a fundamental issue in sediment transport theory and engineering practice. Whilst Shields curve often is used to determine the threshold of sediment movement under unidirectional current conditions, it is unclear whether it can be directly applied for the wave or combined wave-current conditions. The study developed adaptive criterion curves describing incipient motion of sediment under wave and current conditions based on the flow pattern around the sediment particles. Firstly, the flow pattern law for fixed particles was recognized based on the friction law under various dynamic conditions (wave, current, and their combinations), and the flow pattern demarcations for incipient sediment motion were obtained with the threshold conditions for sediment movement under various dynamic conditions combined. Secondly, the exact shape of the Shields curve in each flow regime was derived under the current condition. By combining the flow pattern demarcations for incipient sediment motion under the wave condition, the criterion curve under the wave condition was derived. By combining the flow pattern demarcations for incipient sediment motion under the combined current-wave condition, the criterion curve for sediment incipient motion under the combined current-wave condition was derived. The results indicated that the flow pattern around incipient particles includes laminar, laminar-rough turbulent transition, and rough turbulent regimes. The criterion curves for sediment incipient motion under various dynamic conditions stayed the same in the laminar and rough turbulent regimes, but different in the transition regime. Depending on the relative strengths of the currents and waves, the shape of the criterion curve under the combined current-wave condition transitions adaptively between the criterion curve under the current condition and the criterion curve under the wave conditions. [ABSTRACT FROM AUTHOR]

Distribution uniformity is critical to achieve high performance for proton exchange membrane fuel cell (PEMFC) stacks. In this work, air flow distribution of a 30 kW "U-type" stack of 100 unit cells is investigated by computational fluid dynamics (CFD) simulation, Burgers vortex model is introduced to describe the mechanism of flow maldistribution. Three cases are presented to evaluate the effects of vortexes on the distribution uniformity under various average current densities, and obtain optimized design for better uniformity. The results show that the vortexes usually generate in the feed header, the flow vortex structures are governed by the feed header's configuration. The distribution uniformity reduces dramatically with the increase of current density and the generation of vortexes. The cells that locate in the positions of vortexes get less flow allocation than other cells, distribution uniformity can improve by optimizing the feed header's configuration to change the vortex structure of flow field. [Display omitted] [ABSTRACT FROM AUTHOR]

Degradation performance of photovoltaic (PV) modules by real weather conditions has become increasingly problematic. In the desert climate, dust accumulation is one of the main concerns that may cause a significant deterioration of PV efficiency. In the present work, experimental investigations were carried out to understand the effect of dust on the electrical performance of PV modules under Toujounine, Nouakchott, Mauritania weather conditions. The measurements were performed with an I-V tracer ftv200. The measured parameters were I-V and P-V curves, open-circuit voltage (Voc), short-circuit current (Isc), current and voltage at maximum power (Imp and Vmp) and maximum power (Pmax); as well as the measurement of temperature of panels and Irradiation. The study was carried out according to the following cleaning scenarios: panels cleaned before each measurement (Clean panels 01), panels undergoing systematic cleaning with the central unit (Clean panels 02) and chains undergoing no cleaning (Dusty panels 03). Then, the modeling of reliability as a function of maximum power by Weibull's law, for clean and dusty panels is evaluated. According to the experimental results, disturbances in I-V and P-V curves for dusty panels were noticed. Also, a decrease in the Isc and the Imp for dusty panels compared to clean panels was found. These results are explained by the effect of dust accumulation on the module's surface, which blocks the solar radiation and thus reduces the conversion efficiency of PV modules. Again, dust reduces the output power of photovoltaic modules by 21.57% for dusty panels per clean panels. Finally, a low reliability for dusty panels compared to clean panels was found, due to the loss in the output power under the dust effect. These results clearly show the importance of properly maintaining and servicing the photovoltaic modules to avoid their degradation by dust deposits. • Effect of dust on PV performance is experimentally studied in a Sahelian environment. • Dust accumulation reduces the power output by 21.57%. • Reliability modeling by Weibull's law as a function of maximum power is evaluated. • Reliability of clean panels is higher than the reliability of dusty panels. [ABSTRACT FROM AUTHOR]

Modulation of electric currents through single-molecule junctions is usually achieved by synthesis of molecules with desired functionalities, in conjunction with suitable molecule–electrode contacts through specific anchoring groups. An alternative to this approach, barely explored so far, is to use structured electrodes, where conductivity could eventually be controlled by changing the specific anchoring site within the very same electrode. Here, we theoretically investigate how to exploit the pronounced anisotropy of corrugated graphene deposited on Ru(0001) (Gr/Ru) to tailor single-molecule conductivity in 4-aminophenyl and 4-aminobenzonitrile. We show that currents induced in the upper and lower anchoring positions in the Gr/Ru moiré are substantially different, irrespective of the chosen molecule. The magnitude of these currents can differ by as much as an order of magnitude at specific bias voltages. We also show that both molecules display rectifying properties, which can differ by up to a factor of five in different anchoring sites. Interestingly, the observed modulations strongly depend on the chemical binding nature between the molecule and the electrode, (strong) covalent bond for 4-aminophenyl and (weak) physisorption for 4-aminobenzonitrile. All this suggests that Gr/Ru can be an ideal electrode to modulate single-molecule electric conductivity under experimental conditions that are available in many laboratories. [Display omitted] • Gr/Ru electrodes can be used to tailor single-molecule conductivity. • Molecule–electrode interaction strongly affects the current. • The asymmetry of the junction influences the rectification ratio. • Transport properties are not affected by the quantum dot located at the hill-site. [ABSTRACT FROM AUTHOR]

A fiber optic current sensor (FOCS) demodulation algorithm based on differential-self-multiplication (DSM) is proposed, which is insensitive to the variation in phase modulation depth. It is theoretically analyzed and experimentally verified, compared with two traditional demodulation algorithms in this paper. DSM algorithm reduces demodulation errors caused by phase modulation depth variation that will cause harmonic amplitudes to approach zero. And the variation in phase modulation depth can be simulated by changing modulation voltage. In experiments, where the modulation frequency is 350 kHz and the modulation voltage ranges from 0.5 to 9 V, demodulation currents with DSM algorithms are not only more accurate but also more stable than traditional demodulation algorithms. In addition, the robustness of the DSM algorithm is demonstrated by repeating the experiment at different modulation frequency ranges from 100 to 600 kHz. This work provides a stable demodulation algorithm for FOCS, which can be extended to the applications in demodulation for other phase interferometers. • An algorithm that is insensitive to variation in phase modulation depth is proposed. • The proposed algorithm is compared with two traditional demodulation algorithms. • Repeated experiments at different modulation frequencies to demonstrate robustness. [ABSTRACT FROM AUTHOR]

The Pelletron at the University of Melbourne is a DC particle accelerator that has been used for materials analysis and ion implantation since its installation in the 1970s. Today, it is primarily used to produce proton and helium beams up to 3.5 MeV and 1.5 MeV respectively, for three beamlines with a range of different experiments. The beam stability and fundamental beam parameters such as the transverse phase space distribution and emittance have not been previously investigated in detail. We have performed systematic measurements to determine the beam current variation, finding persistent fluctuations: our study determined that internal wire scanners used for monitoring the beam profile contribute to a periodic current drop. We also found that large terminal voltage oscillations reduce the average current. In addition, the phase space has been measured using a custom-built slit-grid apparatus. We found that the Courant–Snyder (Twiss) parameters are a function of the operational characteristics of the Pelletron, with the emittance more than doubling between measurements. To parametrise the beam despite the fluctuations, we introduce a 'minimum bounding ellipse' described by a set of Courant–Snyder parameters that is representative of the beam characteristics for all the measurements: for our data, this has β = 8.2(5) m, α = -5.2(3), and an emittance of 0.34(3) mm mrad. These parameters will enable future beamline design in Melbourne, and give an indication for the requirements at other Pelletron facilities. Our characterisation techniques can provide a low-cost method to probe beam parameters for improvements in the operation and efficiency of similar DC accelerators, allowing for more accurate measurements and reduced data acquisition times. [ABSTRACT FROM AUTHOR]

The growth kinetic behaviors of the Cu/Al system under current were investigated. The current was shown to significantly promote the growth of the intermetallic (IMC) layer. The growth rate constant of the Al 4 Cu 9 layer under current was approximately 3.26 times higher than that processed without current. Moreover, the current direction leads to a significant difference in the growth rate of the IMC layer, which was attributed to the electromigration effect. Based on the traditional thermal-activated theory and electromigration theory, an electromigration and thermal dual-activated growth kinetic model incorporating the contributions of Joule heat and the nonthermal effect was constructed. The growth kinetic behaviors of the Al 4 Cu 9 layer were investigated by applying this model. The calculated growth activation energies under different current densities were almost constant and close to 130 kJ/mol. The experimental data were applied to verify the model, and the results showed that the model was in good agreement with the experimental results. • 1. The current was shown to significantly promote the growth of the IMC layer. • 2. The current direction leads to a significant difference in the growth rate of the IMC layer. • 3.An IMC growth kinetic model incorporating the contributions of Joule heat and electromigration was constructed. [ABSTRACT FROM AUTHOR]

We prove moderate deviation principles for the tagged particle position and current in one dimensional symmetric simple exclusion processes. There is at most one particle per site. A particle jumps to one of its two neighbors at rate 1 / 2 , and the jump is suppressed if there is already one at the target site. We distinguish one particular particle which is called the tagged particle. We first establish a variational formula for the moderate deviation rate functions of the tagged particle positions based on moderate deviation principles from hydrodynamic limits proved by Gao and Quastel (2003). Then we construct a minimizer of the variational formula and obtain explicit expressions for the moderate deviation rate functions. [ABSTRACT FROM AUTHOR]

An analytical model of an array of moored floating flexible net cage systems is developed to study the dynamics and wave loads on the net cages under the linear water wave theory and small-amplitude wave response assumption. The Fourier–Bessel series expansion of the velocity potential is derived for the regions enclosed under the open-water and cage systems and their proximity. The theoretical solution is obtained by employing the least squares approximation method along with matching the velocity and pressure at the fluid-structure interfaces. The present result of horizontal displacement and horizontal wave load are compared with a published finite element analysis and with experimental data sets, respectively. Further, the results of cage displacements, cage accelerations, and wave loads on the different arrangements for mooring stiffness, cage radius, cage heights, and current speeds are compared and analysed. Moreover, the present analysis will be helpful to understand designing further a multiple floating fish cage system with flexible floaters application to offshore aquaculture. • A semi-analytical model for wave interaction with an array of moored flexible cylindrical net cage is developed. • The analytical solution is obtained using Fourier Bessel series solution and least squares approximation method. • The obtained results of the cage displacement compared well with the numerical FEA simulation in the literature. • The cage displacements and wave loads for different design parameters and cage arrangements are analysed in detail. [ABSTRACT FROM AUTHOR]

Plastic waste has become the most significant component of marine debris, while research on traces of marine plastic waste related to the condition of Indonesian waters is still limited. Therefore, this study examines the movement patterns of plastic marine debris in Indonesian waters. Simulations were carried out for one year (2013) using the HAM burg S helf O cean M odel (hydrodynamic model) and Lagrange trajectory. The approach treated the simulated particles as conservative particles floating at sea. Even though the percentage is small (±16 %), Indonesia contributes to transboundary marine debris in the Pacific Ocean, Indian Ocean, and the South China Sea due to the influence of the south equatorial currents moving from north and south of Indonesia. Most of the plastic marine debris remains in Indonesian waters (±80–84 %) and moves back and forth due to the influence of the monsoon currents. Therefore, the Java Sea becomes a crossing point and accumulates plastic marine debris. • Research on plastic marine debris covering all Indonesian waters is minimal, even though plastic waste has become the most significant component of marine debris. • Indonesian waters are the crossroads of world plastic marine debris. • Through a presidential decree and national plan of action, Indonesia has committed to reducing marine debris in its waters by 70 % by 2025. [ABSTRACT FROM AUTHOR]

High-temperature proton exchange membrane (HT-PEM) fuel cells were more useable than traditional low-temperature proton exchange membrane fuel cells. To investigate the current density distribution in a single HT-PEM fuel cell with a poly (2, 5-benzimidazole) membrane, a modified current distribution measuring device was developed. This device included not only a current distribution measuring gasket to collect local current but also a segmented gas diffusion layer (GDL) to hinder electron transfer in the GDL along the gas flow direction. The effects of this device installation configuration and operating conditions on the current density distribution were analyzed. One of the important findings was that proton transfer along an in-plane direction in the membrane and electron transfer along an in-plane direction in the GDL really occur in HT-PEM fuel cells. These results were very helpful for the optimization of the flow field and operating parameters of the HT-PEM fuel cells. • A modified current distribution measuring device was developed. • Proton transfer along in-plane direction in the membrane occurs in HT-PEM fuel cells. • The current density decreases along the reactant gas flow direction. • Optimal hydrogen flow rate improves the performance of the HT-PEM fuel cell. [ABSTRACT FROM AUTHOR]

Large turbine farms in strong tidal flows could contribute significantly to the global demand for renewable energy. Key to developing large scale power generation is determining how many turbines are required to deliver a given amount of power from proposed sites. Answering this question is computationally difficult, as large-scale power extraction changes the strength of the currents driving the turbines. As a consequence, the large hydrodynamic models used to assess the tidal current resource must be run many times to optimize power output for every potential site and farm size. This paper outlines an approach that can rapidly assess farm power output using an existing hydrodynamic model. This approach is aimed at rapidly determining the most promising farm sites, sizes and shapes within a region, enabling work with more detailed, realistic and slower models to focus on a smaller number of farms. The approach is used to assess how much of Cook Strait, New Zealand's 15,000 MW potential could be realized with current generation turbines. A basic economic analysis suggests that a 90 MW farm with 95 20 m-diameter turbines might be viable in Cook Strait, if turbine manufacturing costs fall, or energy prices increase, by around 25%. • Rapid assessment of large-scale tidal turbine arrays with an existing dynamic model. • Enabling initial assessment of many sites and farm sizes to identify a few for in depth assessment. • A 90 MW farm with 95 turbines might be viable in Cook Strait in the near future. [ABSTRACT FROM AUTHOR]

Effect on microbial fuel cells (MFCs) for decolorization of Congo red by Poly (aniline-1,8-diaminonaphthalene) (PANDAN) modification, current and electroactive biofilms (EABs) is investigated. With the synergism of the three factors: PANDAN modification, current and EABs (A2 reactor), the COD removal and decolorization rate significantly increase to 88% and 97%, as well as the Congo red is thoroughly degraded. The decolorization performance comparison and Redundancy analysis (RDA) results indicate that the EABs take more responsibility (contribute ~ 50%) for the decolorization, rather than the modification and current. Therefore, the effects and mechanism of PANDAN modification and current on EABs are further revealed by the Confocal Scanning Laser Microscopy (CSLM) and high-throughput sequencing analysis. The effects of current (anodic dynamical microenvironment), material adsorption, and electron transfer mediating act comprehensively on the thickness, viability, EPS and microbial community of the EABs, among which the relationship is discussed in depth by hierarchically comparison, with "independent and additional effects". It is demonstrated that the modification, current and EABs present the synergistic effect and promote each other in the performance of the decolorization MFC. Image 1 • Synergism of modification, current and EABs improved MFC's decolorization. • EABs played the most important role, with ~50% contribution to the decolorization. • Modification, current and EABs presented synergistic effect and promoted each other. • Factors as independent or additional led different performance and mechanisms. [ABSTRACT FROM AUTHOR]

Cholecystokinin (CCK) is a peptide that has been implicated in pain modulation. Acid sensitive ion channels (ASICs) also play an important role in pain associated with tissue acidification. However, it is still unclear whether there is an interaction between CCK signaling and ASICs during pain process. Herein, we report that a functional link between them in rat dorsal root ganglion (DRG) neurons. Pretreatment with CCK-8 concentration-dependently increased acid-evoked ASIC currents. CCK-8 increased the maximum response of ASICs to acid, but did not changed their acid sensitivity. Enhancement of ASIC currents by CCK-8 was mediated by the stimulation of CCK2 receptor (CCK2R), rather than CCK1R. The enhancement of ASIC currents by CCK-8 was prevented by application of either G-protein inhibitor GDP-β-S or protein kinase C (PKC) inhibitor GF109203×, but not by protein kinase A (PKA) inhibitor H-89 or JNK inhibitor SP600125. Moreover, CCK-8 increased the number of action potentials triggered by acid stimuli by activating CCK2R. Finally, CCK-8 dose-dependently exacerbated acid-induced nociceptive behavior in rats through local CCK2R. Together, these results indicated that CCK-8/CCK2R activation enhanced ASIC-mediated electrophysiological activity in DRG neurons and nociception in rats. The enhancement effect depended on G-proteins and intracellular PKC signaling rather than PKA and JNK signaling pathway. These findings provided that CCK-8/CCK2R is an important therapeutic target for ASIC-mediated pain. • There is a functional link between CCK signaling and ASICs during pain process. • CCK-8 enhances the electrophysiological activity of ASICs in rat DRG neurons. • CCK-8 sensitizes ASICs through CCK2R and a PKC signaling pathway. • Peripheral CCK-8/CCK2R also exacerbates acid-induced nociceptive responses in rats. [ABSTRACT FROM AUTHOR]

• The proposed method is the operation of DNN and GBDT together called as DNN-GBDT. • A shadow prior map is constructed by using DNN-GBDT and statistical characteristics. • The performance of the proposed method is implemented in MATLAB. • The key aim is to improve energy production performance of photovoltaic array. • The PV system is dynamically tracking the shadow with the proposed method. This manuscript proposes an effective hybrid approach for shadow detection to increase the energy production of solar photovoltaic (PV) arrays. The proposed method is the joint operation of a deep neural network (DNN), and a gradient boosting decision tree (GBDT), together called as DNN-GBDT. The key aim is to improve the energy production performance of photovoltaic arrays. The proposed method dynamically reconfigures the PV system by tracking the shadow. The proposed method contains the following: (1) a camera system constantly monitors the photovoltaic array for moving the shadow track, (2) the image processing unit identifies the shading parts as full or partial, (3) the control decision unit finds the optimum panel layout. Then, by merging the original image and the shadow prior map, the deep neural network (DNN) efficiently trains the shadow samples. The output received is given to the GDBT classification and is processed by the identified and the background image to detect the foreground region. By this process, the normal region and the shadow region are detected. The performance of the proposed method is implemented in MATLAB platform and is compared with various existing methods. The maximum power of PV is 490 W, which is higher than the existing methods. [ABSTRACT FROM AUTHOR]

The wave-powered boat is a kind of mobile marine platform that can convert wave energy into thrust through the rotation of the hydrofoils. The rotation control method of the hydrofoil has a significant impact on the propulsion performance of wave powered-boats when considering ocean currents. In this paper, by establishing an equivalent instantaneous optimization model for the motion of the hydrofoil, the rotation angle that can obtain the maximum thrust is analyzed, and the relationship between the rotation angle, hydrofoil motion velocity as well as the current velocity is obtained. Subsequently, the propulsion performance of the hydrofoil under the active control method is compared with that under the passive control method through the fluid-multibody coupled analysis, and the motion parameters of the hydrofoil are explored, thus the feasibility of active control when considering the ocean currents is verified. It can be seen that the active control method based on the optimal rotation angle equation can significantly improve the propulsion performance of the wave-powered boat in the presence of currents. Under the passive control method, either increasing the stiffness or increasing the co-current velocity will make the rotation process of the hydrofoil fluctuate and disorderly. In contrast, the active control method can stabilize the rotation process of the hydrofoil, and the hydrofoil is always in a position where the maximum thrust can be obtained during rotation, thus making the propulsion performance better. The relevant research in this paper can provide a reference for similar research of the wave-powered boat. • An instantaneous optimization analysis model of the hydrofoil motion is established. • The relationship between the optimal rotation angle, hydrofoil motion velocity as well as the current velocity is obtained. • The propulsion performance of the hydrofoil under different control methods is compared. [ABSTRACT FROM AUTHOR]

Dynamically installed anchor is an innovative and cost-effective technology in marine foundation engineering. However, most of the existing researches on the hydrodynamic characteristics of dynamically installed anchors are limited to their free-fall installation performance in water without considering the action of marine environmental loads such as current. Therefore, this study aims to investigate the hydrodynamic performance of dynamically installed anchors subjected to current in a systematical manner. A complete three-dimensional CFD model is firstly established using "dynamic model analysis" method. Then, the effects of anchor geometric characteristics on the installation efficiency (i.e., penetration velocity and drag coefficient) and installation positioning accuracy (i.e., lateral velocity and displacement, and inclination angle) of the anchors subjected to current are systematically studied using the established CFD model. The influences of current velocity, current direction and geometric characteristics including anchor shaft geometry and anchor fin geometry on the hydrodynamic characteristics of anchor are discussed. Based on the obtained findings, some practical design recommendations are given, and a simple semi-empirical method for estimating the falling velocity and inclination angle of dynamically installed anchor subjected to current considering anchor geometric effects is finally proposed, which may benefit the engineering design of dynamically installed anchors. • Effects of anchor geometry characteristics on hydrodynamic performance of DIAs under current action were investigated. • Practical significance of geometric design and recommended configuration of DIAs under current action were provided. • A semi-empirical method for estimating the falling velocity and inclination angle of DIAs under current action was proposed. [ABSTRACT FROM AUTHOR]

• 80% of energy usage during electrodialytic extraction of phosphorus can be avoided. • 80–98% of the energy is used to stir the waste suspension during extraction. • A dual-stage approach allows reducing experimental time from 9 d to 7 d. • Reducing stirring to 25% of the time does not affect phosphorus extraction yields. • The use of pulse current decreases phosphorus extraction and is not recommended. This work assesses the possibility of energy optimisation during the electrodialytic extraction of phosphorus from the municipal solid waste digestate. Strategies tested for energy optimisation consisted in (i) using a dual-stage extraction approach; (ii) replacement of continuous stirring by pulse stirring and; (iii) utilisation of pulse electric current as an alternative to a constant current. Experiments were carried out using different stirring profiles (continuous stirring, pulsed stirring, manual stirring and no stirring) and different profiles for generating the electric field (continuous current and pulsed current). Dual-stage approach decreased the energy consumption by 30%. Energy was mainly used in the stirring operation (80%). Applying this strategy caused a faster acidification of the waste suspension and reduced the time required for the extraction. As for the second strategy, use of pulse stirring, it is possible to save energy by operating the stirrer 25% of the time, without compromising the phosphorus extraction values, which are close to 90%. Corresponding energy savings reached 70%. The third strategy tested, use of pulse current, had as side-effect a significant decrease of the phosphorus extracted, so the implementation of pulse current is not recommended. Overall, the energy efficiency of the electrodialytic extraction of phosphorus can be improved by 80% through the use of the dual-stage approach and the use of stirring for 25% of the time. There is also a potential in further reducing the energy use by further improving the stirring system. [ABSTRACT FROM AUTHOR]

Laboratory experiments and field application of high-voltage electrical pulse (HVEP) technology, a good method for coalbed methane (CBM) enhancement, have achieved great progress. However, previous studies mainly concentrated on the crushing effect of a single pulse on coal, ignoring the influence of multiple cyclic electrical pulses on the pore structure. Besides, the current in electrical breakdown was rarely studied. In this study, the effect of cyclic number on pore variation was investigated, and the mechanism of electrical breakdown was discussed by measuring the current waveform. Moreover, the micro fissure and pore variations of coal before and after electrical breakdown were measured by adopting scanning electron microscopy (SEM) and low temperature liquid nitrogen adsorption (LT-N 2 A). Under the action of cyclic HVEP, both Linhua (LH) anthracite coal and Hongliu (HL) bituminous coal can be crushed into small pieces. SEM results indicate that the number of cracks increase with the number of cycle. LT-N 2 A analyses show that the cumulative pore volumes and surface areas of LH and HL coals both increase after electrical breakdown, so does the pore structure fractal dimension, which provides a smoother channel for CBM desorption. Additionally, the great energy instantly injected into the coal could produce huge expansion stress and immediately break the coal from inside. Current waveforms during the breakdown demonstrate that the peak current increase with the number of cycle, whereas the breakdown time decrease with it. This indicates the alteration of electrical properties of coal during the breakdown, which affects the next discharge. • Fracture produced by cyclic high-voltage electrical pulse was investigated. • The crushing effect increases with the cyclic number grows. • The electrical breakdown time and peak current were affected by the cyclic number. [ABSTRACT FROM AUTHOR]

Electrical neuromodulation via implanted electrodes is used in treating numerous neurological disorders, yet our knowledge of how different brain regions respond to varying stimulation parameters is sparse. We hypothesized that the neural response to electrical stimulation is both region-specific and non-linearly related to amplitude and frequency. We examined evoked neural responses following 400 ms trains of 10–400 Hz electrical stimulation ranging from 0.1 to 10 mA. We stimulated electrodes implanted in cingulate cortex (dorsal anterior cingulate and rostral anterior cingulate) and subcortical regions (nucleus accumbens, amygdala) of non-human primates (NHP, N = 4) and patients with intractable epilepsy (N = 15) being monitored via intracranial electrodes. Recordings were performed in prefrontal, subcortical, and temporal lobe locations. In subcortical regions as well as dorsal and rostral anterior cingulate cortex, response waveforms depended non-linearly on frequency (Pearson's linear correlation r < 0.39), but linearly on current (r > 0.58). These relationships between location, and input-output characteristics were similar in homologous brain regions with average Pearson's linear correlation values r > 0.75 between species and linear correlation values between participants r > 0.75 across frequency and current values per brain region. Evoked waveforms could be described by three main principal components (PCs) which allowed us to successfully predict response waveforms across individuals and across frequencies using PC strengths as functions of current and frequency using brain region specific regression models. These results provide a framework for creation of an atlas of input-output relationships which could be used in the principled selection of stimulation parameters per brain region. • Stimulation response varies nonlinearly with stimulation frequency. • Response properties are region specific, conserved across individuals and species. • An 'atlas' of response characteristics can aid design of neuromodulation systems. [ABSTRACT FROM AUTHOR]

The paper deals with the study of the influence of hydrodynamic factors (current, water level fluctuations, and wind driven wave) on the structure of epiphyton occurring on macrophytes of various ecological groups in the Kanev Reservoir (the Dnieper River, Ukraine). The reservoir is subdivided into the river and lake sections, including the transit and non-transit zones. It has been found that the main factors inhibiting the development of epiphyton in the main riverbed of the river section include high current velocities conditioned by discharge currents and water level fluctuations, in the bays of the river section – water level fluctuations, whereas in the transit zone of the lake section – wind driven wave. The performed investigations have shown that the increase in water movement conditioned by high current velocities, water level fluctuations, and wind driven wave results in the decrease in epiphyton species richness, in changes in its species composition, taxonomic structure, dominant complex, dimensional structure, and its numbers and biomass structure, and also in the decrease in the quantitative indices of its development. It has been found that the average number of species in a sample and epiphyton numbers and biomass depended inversely on current velocity, water level fluctuations, and wind driven wave. As a consequence, the increase in water movement can result in the lower oxygen release and organic matter production by this community, and the decrease of nutrient uptake and pollutants accumulation, thus limiting the role of epiphyton in water bodies self-purification. At the same time, it has been shown that water movement variously influenced algal communities occurring on the substrates of different types, including epiphyton found on macrophytes and periphyton registered on solid artificial inorganic substrates.The obtained data can be used in predicting the ecological state of the designed water bodies. [ABSTRACT FROM AUTHOR]

Abstract Volatile fatty acids (VFAs) especially acetate concentration have been proved to be a sensitive and reliable indicator for many anaerobic processes such as anaerobic digestion (AD). Microbial fuel cells (MFC) have been demonstrated as a promising VFAs sensor due to simple reactor design and operating conditions among microbial electrochemical biosensors. However, the conventional MFC biosensors may fail to distinguish between VFAs and other organics as real digestates containing complex organics and microbes are fed into anode directly. In the present study, an MFC based biosensor was developed and operated in a smart way for selective acetate detection. In the biosensor, acetate ions contained in the AD sample was first fed into the cathode, and then acetic ion transferred through the membrane from the cathode to anode chamber where it was further used as the sole substrate by pre-enriched electroactive biofilm for the current generation. A linear correlation between the current density and acetate concentrations (0.5–20 mM) at varied reaction time (1–5 h) was established. Then, the interference from propionate, butyrate, isobutyrate, and glucose on the performance of the biosensor was evaluated. Furthermore, the influence of sample temperatures (37 and 55 °C) was also studied. Finally, the VFAs content in real AD effluent with this biosensor was measured. The results corresponded well with gas chromatographic measurements. This simple, and reliable biosensor could serve as a promising alternative method for acetate detection in the AD process or any other acetate-rich fluids. Graphical abstract Unlabelled Image Highlights • MFC based biosensor for acetate monitoring in AD process with high accuracy • Linear detection range of 0.5–20 mM established within 5 hour response • High selectivity to acetate and less interference from other VFAs • Digestate with temperature of 37 °C had no significant influence on biosensor [ABSTRACT FROM AUTHOR]

Highlights • The two breakdown types of coal by HVEP in air environment were found. • Liquid nitrogen adsorption, SEM and 3D-XRM results suggest that HVEP is a potential method for CBM extraction. • A new method for fracturing and permeability enhancing is proposed combining with the hydraulic fracturing and HVEP. Abstract In order to enhance the gas extraction rate of low-permeability coal seams, a study was made on variation characteristics of pore structure of the coal saturated by NaCl solution under the effect of high-voltage electrical pulses (HVEP) by adopting a self-designed experimental system of fracturing and permeability enhancing of the coal with HVEP. In addition, current waveforms in the process of electrical breakdown were also investigated. The results revealed the two types of electrical breakdown of the coal in air environment, namely, surface breakdown and internal breakdown with three forms of breakage, namely, complete comminution, breakage from one side and cracks on the surface. Furthermore, the coal was broken due to internal tension under the influence of HVEP. Based on energy dispersive spectroscopy (EDS) analysis, the coal underwent both physical and chemical changes where the current flowed. Results of scanning electron microscope (SEM) demonstrated that the higher the breakdown voltage, the more the fissures in coal, and the better the breakage effect. Fissures in the coal were observed via the 3D-XRM to extend radially from the center to boundary areas with the breakage effect weakening gradually from anode to cathode when needle electrode discharged. Besides, these fissures were interconnected with each other. The result of liquid nitrogen adsorption suggested that electrical breakdown could effectively boost gas desorption by improving fissures as well as pores and micropores in the coal. Characteristics of the current waveform showed that great thermal expansion stress was caused by huge energy injected into the coal in an instant. During the electrical breakdown of coal with the same voltage, the peak current was different which increased with the growing of breakdown voltage. [ABSTRACT FROM AUTHOR]

Abstract The luminosity of lightning channel is closely related to the lightning current. In the present paper, a lightning channel luminosity detection system (LCLDS), comprising of an avalanche photodiode module, a neutral density filter, an extension tube and an adjustable horizontal slit, is assembled. By using the impulse current generator, lightning impulse currents with different amplitudes and also different waveforms were produced in a 15-mm open-air gap between two graphite-rod electrodes. The luminosity and the current of discharge channel were measured synchronously. The experiments looking into the influencing factors of luminosity measurement, including the alignment of the silt and the slit width, were carried out. Obtained results show that the slit opening center of LCLDS should be aligned to the center of the discharge gap. Otherwise, in the case of improper alignment, the measured luminosity waveforms associated with the same injected current might be quite different in the amplitudes as well as in the waveforms. Moreover, the peak luminosity increases linearly with increasing slit width, whereas the luminosity waveforms are practically unaffected, implying that, in the practical application, the slit width can be adjusted to alter the luminosity signal output according to the actual need. Obtained results here can establish the foundation to develop the correlation between the current and the corresponding luminosity in the future. Highlights • The slit opening center of lightning channel luminosity detection system should be aligned to the center of the discharge gap. • The humps of luminosity waveforms found in the lightning flashes is due to improper alignment. • Peak luminosity increases linearly with increasing slit width. [ABSTRACT FROM AUTHOR]

Highlights • An ANN model for predicting short-term VIV fatigue damage of TTR was developed and trained successfully using generated 21,532 datasets. • The proposed ANN technique was verified by test cases of current. • It can serve as an alternative approach for VIV fatigue damage assessment at early design stage of TTR. Abstract Marine riser is the critical component transporting hydrocarbon and fluid from well to the platform and vice versa. Riser experiences vortex-induced vibration (VIV) caused by current, leading to fatigue damage. Estimation of VIV fatigue damage is essential in designing feasible and operable riser. A simplified approach for predicting fatigue damage is required to reduce the computation time to analyse the fatigue damage. This study aims to propose a simplified approach to predict VIV fatigue damage of top tensioned riser (TTR) using artificial neural network (ANN). A total of 21,532 riser model was generated with different combination of six main input parameters: riser outer diameter, wall thickness, top tension, water depth, surface and bottom current velocity. The modal analysis was performed using OrcaFlex and VIV fatigue damage of the riser was computed using SHEAR7. The six input parameters and corresponding fatigue damage results made up the database for training a 2-layer neural network. Weight and bias values acquired from the training of ANN were used to develop the VIV fatigue damage prediction model of the riser. The hyperparameters of the ANN model were tuned to optimize performance of the model. The results showed the final ANN model predict fatigue damage well with shorter time compared to conventional semi-empirical method. Hence, the proposed approach is suitable to be used for prediction of VIV fatigue damage of TTR at early design stage of TTR. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

Highlights • Thermal and electrical performances were measured using indoor test cell for crystalline silicon based PV-vacuum glazing. • Maximum PV cell temperature was achieved 97 °C under 1 sun exposure (1000 W/m2) • Overall heat transfer coefficient was 0.8 W/m2 K for this glazing. • Solar factor was calculated for this PV-vacuum glazing. Abstract Combined semi-transparent PV-vacuum glazing provides low overall heat transfer coefficient, reduces solar heat gain, generates clean electricity and admits comfortable daylight. In this work, thermal and electrical performances of a multicrystalline silicon based PV-vacuum glazing were characterised using indoor test cell. For this particular combined system, PV covered 32% of the glazing area. Two different combinations of PV-vacuum glazing systems were manufactured where for the first case vacuum glazing faced test cell external environment (VPS) and for the second case vacuum glazing faced test cell internal environment (SPV). SPV type was found to have superior performance as PV cell achieved lower temperature than VPS type after 125 min exposure under 1000 W/m2 constant intensity from a simulator. For this type PV-vacuum glazing, overall heat transfer coefficient (U -value) was 0.8 W/m2 K and the solar factor was 0.42. U -value of this PV-vacuum glazing was 66% lower and the solar factor was 46% lower than PV double-glazing. Close power drop from PV due to elevated temperature was observed for both PV-double and PV-vacuum glazing. [ABSTRACT FROM AUTHOR]

Sponges play a vital role in the world’s most complex and vulnerable marine ecosystems. Various in situ studies have suggested that sponge morphologies (developed from exposure to a range of biophysical factors) can be considered as ecological indicators to current detrimental environmental changes such as climate change, overfishing, pollution and dredging for coastal development. Regional and long-term taxonomic data on sponges within each geographic range is not always available, especially from the Great Barrier Reef (GBR), due to dearth of sponge research. In this study, to understand large-scale variation and advance sponge research and knowledge, morphological characteristics were adopted as a rapid practical way to identify sponges from photo-transect images of a long-term dataset from the GBR. Biennial surveys were carried out in 2008–2014 from 28 pairs of take and no-take zones of the GBR. To evaluate the temporal changes in sponge morphology and correlation between abiotic factors, remote-sensed data such as chlorophyll a , current, wave height and sea surface temperature (SST) during the survey period were analyzed. Results showed sponges were ubiquitous in all six surveyed locations and their distribution was spatially heterogeneous. Encrusting forms were dominant followed by upright, massive, cups and tabular growth forms. Sponges were more prevalent in Innisfail, Pompey and Townsville compared to Cairns, Swain and Capricorn Bunker. Biennial observations showed greater sponge coverage in 2010 and 2014, especially in the central GBR, which may be related to the geomorphology and habitat of reefs along with its influence by wind and wave action. Also, the aftermath of Cyclone Hamish (2009) and Yasi (2011) would have triggered suspended particulate matter that are beneficial to sponge growth. Geostrophic current showed a weak relationship on encrusting, upright and massive forms, whereas, chl- a , wave height and SST appeared to have no effect on sponge morphology, suggesting sponges may be resilient to adverse conditions in the GBR. Whilst selected sponge morphologies can act as environmental proxies to monitor adverse conditions, further in situ research on other environmental parameters such as turbidity, sedimentation, cyclone, tides are required to bring substantial conclusions on sponge morphologies as ecological indicators. [ABSTRACT FROM AUTHOR]

During the launch operation of subsea equipment in the offshore industry, several factors are important for a safe and economical installation within an operating window. One of these factors is the hydrodynamic coefficients of the equipment to be installed. The coefficients can be obtained, experimentally or numerically, by applying an oscillatory motion that represents the effects of sea conditions and vessel motion, but these applications simplify conditions during a real operation and disregard important effects such as ocean currents. This paper investigates numerically the effect of current together with forced oscillation on the hydrodynamic coefficients of disks by analyzing two influence parameters, the Keulegan-Carpenter number (K C) and the reduced current velocity (V r). A numerical model validation process was carried out in stages to overcome the lack of references on the subject. The model was compared with Direct Numerical Simulation (DNS) results for low Reynolds number (R e), up to 600, in qualitative and quantitative analysis, and then applied to broader conditions found in real operations, with K C up to 3 , V r up to 0.3 , and for high R e , up to 240,000. On the model scale, higher V r generates an increase in the drag coefficient (C d) and a decrease in the additional mass coefficient (C a). Under real scale conditions, the results are similar, with variations of C d up to 300% and of C a up to 36% for low K C. Analysis of the flow topology indicates that K C and V r influenced vortex shedding and convection. Correlations for the hydrodynamic coefficients as functions of K C and V r are proposed, with a R 2 higher than 93%. • Selected RANS turbulent models presented results similar to DNS simulations for cases of forced oscillation with current for low R e. • The analysis was carried out at a higher R e , similar to a real scale, indicating an increase in drag coefficient and reduction in added mass for high currents. • The flow topology due to oscillatory movement and current shows an influence on vortex shedding. • For the first time, the influence of higher K C and current on the hydrodynamic coefficients was established. • Correlations are proposed for the hydrodynamic coefficients as functions of K C and V r , with a R 2 > 93 %. [ABSTRACT FROM AUTHOR]

The role of wave blocking on flexural gravity wave motion with oblique incidence and current is discussed. The oblique wave incidence due to a finite floating elastic plate is investigated using the eigenfunction expansion method. The role of different wave propagating modes on reflection coefficient is discussed. The reflection and transmission coefficients, the surface elevation, and plate deflection in the presence of current are derived. The effects of flexural rigidity and the uniform current speed on reflection and transmission coefficients are analyzed. The resonating nature of reflection coefficient for some fixed values of plate length is observed. Significant effects of different combinations of wave propagating modes of plate covered regions and open water regions on the reflection and transmission coefficients are observed. The wave energy propagation from reflection coefficient decreases whenever the Froude number increases. It has been found that the amplitude of the plate deflection increases as the value of the Froude number increases. The amplitude and wavelength of the reflection coefficient are higher for the combination of the first propagating mode of the plate covered region and the second propagating mode of the open water region. Moreover, it is found that zero reflection and full transmission occurs periodically. Co-propagating waves are found to transmit more energy while counter-propagating waves reflect more energy. Higher values of flexural rigidity result in reduced wave energy transmission. • The effect of current on wave scattering problem is analyzed • The reflection and transmission coefficients are derived in the presence of current. • The role of blocking dynamics on reflection coefficients is discussed • Nature of different combinations of wave propagating modes is discussed • The impact of current on surface elevation and plate deflection is analyzed. [ABSTRACT FROM AUTHOR]

Wave nonlinearity can drive the near-bed sediment transport and nutrient delivery on coral reefs. Previous studies have primarily concentrated on the wave nonlinearity evolution for a specific cross-shore profile and have scarcely taken the effects of currents into consideration. To better understand the nonlinear wave transformation on reef coasts, the wave height distribution and wave nonlinearity evolution are analyzed based on 3D reef-lagoon-channel experiments in a wave basin. By taking the current velocity into consideration, the Glukhovskiy distribution function is improved in calculating the probability of large wave height in the sequence. Wave skewness and asymmetry on the reef and in the channel are parameterized with the Ursell number considering the Doppler effect induced by opposing or following currents. The accuracies for estimating wave skewness and asymmetry are improved by 39% and 66%, respectively. The influence of Doppler effect on wave shapes on the reef flat and in the channel varies significantly with the incident wave heights and reef submergences. Furthermore, it is also noticed that the reduction of local water depth caused by the propagation of infragravity wave troughs increases short-wave skewness at individual wave scale on the middle of reef flat, while its effect on short-wave asymmetry is not significant. • Nonlinear waves are analyzed on a 3D reef-lagoon-channel system. • By taking currents into consideration, the Glukhovskiy distribution function is improved. • Wave nonlinearities are parameterized with the Ursell number considering the Doppler effect. [ABSTRACT FROM AUTHOR]

• We calculated I-V curves, real space charge distribution, transmission spectrum, photocurrent, and thermal current. • Our results show that the zigzag device has excellent photocurrent characteristics. • The direction of photocurrent can be adjusted by changing the wavelength of incident light and adding gate voltage. • The armchair device has excellent IV curve characteristics and good linear characteristics at low voltage. • The armchair device also has good thermoelectric current properties. • The position distribution of covalent bonds in this heterostructure is revealed by the real space charge distribution. In this paper, we calculated current–voltage characteristic curves (IV curves), Conductivity, real space charge distribution, transmission spectrum, photocurrent, and thermal current of the borophene-black phosphorus heterostructure. Our results show that the zigzag device has excellent photocurrent characteristics. The direction of photocurrent can be adjusted by changing the wavelength of incident light and adding gate voltage. The armchair device has excellent IV curve characteristics and good linear characteristics at low voltage. The armchair device also has good thermoelectric current properties. The position distribution of covalent bonds formed between atoms in this heterostructure is revealed by the real space charge distribution. Our results are significant for applying borophene-black phosphorus heterostructure in electric transport devices. [ABSTRACT FROM AUTHOR]

The upper fluid mud layer in muddy environments absorbs wave energy and, in turn, moves due to the wave action. In addition to these two major phenomena of wave-mud interaction, introduction of current in the wave field also changes the wave characteristics as well as the rates of mud mass transport. The present study offers an experimental investigation of wave-current-mud interaction to address the wave transformation and mud mass transport on a horizontal bed. A number of laboratory tests were conducted to measure the mud particle velocities as well as wave attenuation rates under following, opposing, and no current conditions. Both the wave energy dissipation and mud mass transport increase with the presence of opposing currents and decrease when following currents are introduced. A semi-analytical model was also presented and the numerical results are compared with the laboratory experiments, showing acceptable agreements. [ABSTRACT FROM AUTHOR]

A key challenge for ammonia monitoring during nitrogen removal process is the extra cost and toxic reagent consuming. Herein the feasibility of current generated by an integrated microbial electrolysis cell (MEC) - nitrification reactor as an indicator of initial ammonia levels (NH 3 /NH 4 + ) in wastewater was explored. In this loop system, ammonia was first oxidized to nitrate in the nitrification reactor, and then the effluent was introduced into the cathode of MEC where nitrate was reduced as electron acceptor. The correlation between current and ammonia concentration was first investigated with synthetic ammonia-rich wastewater. A good linear relationship (R 2  = 0.9419) was observed between current (0.5130–3.906 mA) and ammonia levels (0–62.1 mg NH 4 + -N/L). Such linear relationship was always obtained regardless of the tested external power supply or wastewater pH. The external electrochemical cell was proved to be an effective pre-conditioning method to remove the disturbance from other possible electron acceptors. Finally, the integrated system was further tested with real waste streams and the results showed no significant difference (p > 0.05) with measurements by conventional methods. This study, for the first time, demonstrated the potential application of the integrated MEC - nitrification system for ammonia monitoring in addition to water treatment. [ABSTRACT FROM AUTHOR]

During the past few decades, there have been many instances of significant damage to coastal infrastructure, especially bridges, due to ocean waves generated by hurricanes and tsunamis. Since ocean waves and currents co-exist and twist with each other in natural marine environments and their interaction may result in more severe damaging waves, taking both of them and their interaction into account is important in better understanding of damage processes of coastal bridges. This paper conducts a numerical investigation on hydrodynamic load on a bridge deck due to joint action of solitary waves and currents. Effects of prominent factors including current velocity, submersion depth, wave height, and water depth have been studied. Efficiency of air vents in reducing the hydrodynamic load has also been discussed. The numerical investigation indicates that, in a linearly pattern, a current in the wave direction leads to a higher maximum of the hydrodynamic force in the horizontal direction, and a current in the opposite direction results in a lower maximum. However, the behaviors of other characteristics of the force, including the maximum of its vertical component and the minimums of its horizontal and vertical components, become complicated and highly nonlinear because of water overtopping on the deck. In addition, a current can play a pronounced role, either positive or negative, in efficiency of air vents in reducing the hydrodynamic load. It is anticipated that the findings in this paper will enhance our understanding on mechanism of bridge damage by waves and may also be useful in design of future coastal bridges. [ABSTRACT FROM AUTHOR]