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The subject of study in this article is the voltage ranges, methods, and tools for prototyping independent sources of power supply and artificial lighting for home appliances with reuse of only widespread components. The goal is to improve the efficiency of the creation and use of independent power supply sources for home appliances. Task: to analyze the history of the development of voltage standards for households; analyze existing autonomous power sources and types of batteries; analyze different loads; find rational voltage ranges based on fundamental values; analyze charge control and balancing circuits for lithium-based batteries; propose the technique of prototyping independent sources of power supply based on reused lithium-ion (Li-ion) accumulators; provide an example of the practical application of the results of research. According to the tasks, the following results were obtained. The evolution of voltage standards of electrical supply networks is analyzed. Types of autonomous power supplies, including pure sine versions, are discussed. The analysis of batteries for autonomous power sources of different chemical compositions is performed. It is proposed to use the water analogy of current and area as an analogy of battery capacity for visual representation of electrical processes. Models of constant current consumption and constant power consumption are considered. It is proposed to reduce the internal resistance of the battery assembly by parallel connection of the reused lithium-ion accumulators. Correspondence of voltage ranges of sequential connection of lithium-ion cells to ensure compatibility with existing devices is investigated. Rational parameters of voltage ranges to ensure compatibility of lithiumion and acid accumulators with the ability to charge directly from solar panels without a charge controller are found. Charge controllers, battery management systems (BMS), and battery balancing circuits are analyzed. A set of steps for reuse of lithium-ion accumulators for the creation of autonomous power sources is proposed. Conclusions. The main contribution of this research is the proposed method of creation of power supply and interior lighting based on the reuse of accumulators without additional components. The discovered and proposed magic numbers of 3, 5, 7, 9, 11 and 13 for series connection of lithium-ion cells allows to obtain the equivalent of standard voltage ranges of 12 V, 19 V, 27 V, 36 V, 42 V and 48 V. The proposed technique of adjusting the voltage of the passive balancer allows adding 4.5 % to the capacity of the battery assembly. The described solutions allow to build the completely scalable autonomous low-voltage electrical supply network with the ability to charge directly from solar panels without expensive charge controllers. [ABSTRACT FROM AUTHOR]

The multiply-accumulator (MAC) unit is the basic integral computational block in every digital image and digital signal processor. As the demand grows, it is essential to design these units in an efficient manner to build a successful processor. By considering this into account, a power-efficient, high-speed MAC unit is presented in this paper. The proposed MAC unit is a combination of a two-phase clocked modified sequential multiplier and a carry-save adder (CSA) followed by an accumulator register. A novel two-phase clocked modified sequential multiplier is introduced in the multiplication stage to reduce the power and computation time. For image blurring, these multiplier and adder blocks are subsequently incorporated into the MAC unit. The experimental results demonstrated that the proposed design reduced the power consumption by 52% and improved the computation time by 4% than the conventional architectures. The developed MAC unit is implemented using 180nm standard CMOS technology using CADENCE RTL compiler, synthesized using XILINX ISE and the image blurring effect is analyzed using MATLAB. [ABSTRACT FROM AUTHOR]

Oscillating hydraulic pressure intensifiers, of the minibooster type, are supplied at the inlet, in the primary, by low-pressure pumps and provide, at the outlet, in the secondary, high pressure to the hydraulic consumers (linear or rotary hydraulic motors under load). The pressure increase in the secondary, proportional to the amplification factor of the intensifier occurs at a much lower flow rate than the supply flow rate, and thus the two hydraulic parameters (pressure and flow rate) at the outlet of the intensifier are affected by oscillations. Because of this, the miniboosters are designed for static applications, which require low displacements of hydraulic motors. The authors aimed to expand the field of use of miniboosters by reducing the flow rate and pressure pulses with the help of hydro-pneumatic accumulators mounted on the primary and secondary of the intensifiers. If these pulsations can be mitigated, then low-pressure pump units of small dimensions, equipped with miniboosters, can be used in dynamic mining-specific applications, in complete safety, such as, for example, those involving relatively uniform displacement, under load, of some hydraulic jacks. A numerical simulation model developed in Simcenter Amesim highlights the effect of using hydro-pneumatic accumulators on the mitigation of flow rate and pressure pulsations of the oscillating hydraulic intensifiers. Numerical simulations performed with and without hydro-pneumatic accumulators mounted on the primary and secondary of the intensifier highlight the following aspects: • hydro-pneumatic accumulators can be used successfully for the partial damping of flow rate and pressure pulses, but they must be dimensioned for each specific application and work optimally for a relatively narrow pressure range; • using hydro-pneumatic accumulators can sufficiently improve the uniformity of displacement and the velocity of displacement of a hydraulic cylinder, so that it can be used in less demanding dynamic applications, as well. [ABSTRACT FROM AUTHOR]

An open center system (OC-System), which is one of the major hydraulic architectures for excavators, has been improved in the world to reduce fuel consumption for global environment conservation and lower operating costs. However, the total system efficiency, including the internal combustion engine (ICE), has not been thoroughly considered. In contrast, a constant pressure system (CP-System) enabling the engine to be driven optimally is developed, but is not accepted in the industry owing to the complexity of the required components. Thus, in this research, a hybrid system combining an OC-System with a CP-System is proposed to improve the total system efficiency. An accumulator, which is used to provide flow rate to actuators, is essential for the new hybrid system, and it is vital to consider the nominal gas volume and pressure level for the accumulator in terms of energy savings and initial cost. Therefore, the influences of accumulator volume and pressure level are discussed in this paper. [ABSTRACT FROM AUTHOR]

Reasoning about commutativity between data-structure operations is an important problem with many applications. In the sequential setting, commutativity can be used to reason about the correctness of refactoring, compiler transformations, and identify instances of non-determinism. In parallel contexts, commutativity dates back to the database (Weihl in IEEE Trans Comput 37(12):1488–1505, 1988) and compilers (Rinard and Diniz in ACM Trans Program Lang Syst 19(6):942–991, 1997) communities and, more recently, appears in optimistic parallelization (Herlihy and Koskinen in Proceedings of the 13th ACM SIGPLAN symposium on principles and practice of parallel programming, 2008), dynamic concurrency (Tripp et al. in Proceedings of the 33rd ACM SIGPLAN conference on programming language design and implementation, PLDI '12, New York, NY, USA, ACM, pp 145–156, 2012; Dimitrov et al. in Proceedings of the 35th ACM SIGPLAN conference on programming language design and implementation, 2014), scalable systems (Clements et al. in ACM Trans Comput Syst 32(4):10, 2015) and even smart contracts (Dickerson et al. in Proceedings of the ACM symposium on principles of distributed computing, PODC '17, New York, NY, USA, ACM, pp 303–312, 2017). There have been research results on automatic generation of commutativity conditions, yet we are unaware of any fully automated technique to generate conditions that are both sound and effective. We have designed such a technique, driven by an algorithm that iteratively refines a conservative approximation of the commutativity (and non-commutativity) condition for a pair of methods into an increasingly precise version. The algorithm terminates if/when the entire state space has been considered, and can be aborted at any time to obtain a partial yet sound commutativity condition. We have generalized our work to left-/right-movers (Lipton in Commun ACM 8(12):717–721, 1975) and proved relative completeness. We describe aspects of our technique that lead to useful commutativity conditions, including how predicates are selected during refinement and heuristics that impact the output shape of the condition. We have implemented our technique in a prototype open-source tool Servois. Our algorithm produces quantifier-free queries that are dispatched to a back-end SMT solver. We evaluate Servois first by synthesizing commutativity conditions for a range of data structures including Set, HashTable, Accumulator, Counter, and Stack. We then show several applications of our work including reasoning about memories and locks, finding vulnerabilities in Ethereum smart contracts, improving transactional memory performance, distributed applications, code refactoring, verification, and synthesis. [ABSTRACT FROM AUTHOR]

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This paper presents the design and simulation of a buck charge controller for lead-acid accumulators used in photovoltaic applications, based on fuzzy control techniques. The proposed design fully implements the three-stage algorithm: bulk, absorption, and flotation, which allows the battery to be accurately charged, ensuring its integrity and durability. The control system consists of two independent fuzzy controllers, the first regulates the current accurately in the bulk stage, while the second regulates the voltage in the absorption, and flotation stages; additionally, it has switching logic, which allows transitioning between the different stages of the algorithm. The system was designed and simulated in MATLAB; and the results show the correct functionality of the design by simulating the charge of 12 V accumulators with capacities from 60 to 120 Ah. Even though in the literature, there are similar works, very few use an algorithm with multiple stages completely, and that can be implemented directly in economic systems such as microcontrollers. This work can be taken as a reference in the design of charge controllers even different from those based on fuzzy logic, which represents an important didactic contribution. [ABSTRACT FROM AUTHOR]

Abstract In this study, TiFe 0.90 Mn 0.10 and TiFe 0.95-x Mnx (x = 0.05, 0.15) with excess in titanium powder samples were synthesized through mechanical alloying (MA) at room temperature under argon atmosphere. The micro-structural and morphological properties of these powder alloys were investigated by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and transmission electron microscopy (TEM). The effects of the substitution of Fe by Mn and the excess of Ti on the electrochemical properties were studied through the galvanostatic, potentiostatic and potentiodynamic polarization methods. The XRD and SEM analysis confirm the presence of the amorphous phase for all the samples. The sample with the lowest Mn content (x = 0) and excess in titanium has the highest maximum discharge capacity and reversibility (224 mAh g−1 and 368 mV). A correlation between the evolution of different electrochemical parameters, cycling, kinetic and redox was observed during the cycling. Graphical abstract Image 1 Highlights • The micro-structural and morphological properties of the Ti-Fe-Mn powder alloys were investigated. • The effect of Fe substitution by Mn and the excess in Ti on the electrochemical properties were studied. • All the electrodes reached their maximum capacities at the first cycle. • A good correlation between the polarization and cycling stability was observed. • The alloy milled with excess in Ti shows the higher value of maximum discharge capacity and Nernst potential. [ABSTRACT FROM AUTHOR]

Studies on the heavy metal concentrations on spider webs in relation to the pathways of pollution penetration (external and internal) have yet to be performed. This work assesses the concentration levels of two heavy metals: essential copper (Cu) and toxic lead (Pb) in spider webs and spiders (females, males and juveniles). Spiders divided into three treatment groups were exposed to the heavy metals in their diet as prey (fruit flies and mealworms larvae) were artificially contaminated with Cu and Pb. In general, we found higher rates of Cu compared to Pb concentrations in spiders and their webs. A positive correlation between levels of Cu and Pb in webs and spiders was found. Males had higher concentrations of both metals Cu and Pb in their bodies and webs compared to females. In an additional experiment, washed webs had significantly less metals than unwashed suggesting the dominance of external pollution in the contamination pathway. [ABSTRACT FROM AUTHOR]

Abstract Seawater piston pump is a key power component for underwater equipment. Low pressure pulsation and vibration have become the key requirements of high quality seawater piston pump in the interest of improving the stability, reliability and stealth of underwater equipment. A new type crankshaft seawater piston pump was studied in this paper. The kinematics of the pistons was analyzed and a simulation model was established. The simulation results indicated that its pressure pulsation rate was as high as 17%. Fortunately, after integrating accumulators and optimizing the precharge pressures, the pressure pulsation rate can be reduced below 5% in the working range. The pump possessed better performance when the accumulators were precharged with optimized multiple pressures than with a single pressure. In addition, experimental analysis was conducted through measuring the pressure pulsation and vibration acceleration under different conditions. The experiment results of the pressure pulsation well agreed with the simulation results. Besides, the vibration acceleration of the seawater piston pump was obviously reduced in wide working range when the accumulators were precharged with the optimized combination multiple parameters. In conclusion, integrating accumulators into pump and optimizing the precharge parameters can reduce the pressure pulsation and vibration acceleration in the working range. Highlights • The kinematic of the pistons was theoretically analyzed and discussed. • The simulation of the seawater piston pump was completed by using AMESim software. • A group of accumulators were integrated into the seawater piston pump. • The precharge parameters were optimally combined. • Experiment was conducted to verify the property of the pulsation and vibration reduction. [ABSTRACT FROM AUTHOR]

Abstract Within the framework of Low Thrust Cryogenic Propulsion (LTCP) systems, a low-temperature accumulator acting as thermal energy storage tank is an interesting option for cyclical processes under intermittent firings avoiding the use of turbopumps in the cryogenic stages. Thus, liquid propellant (oxygen, hydrogen or methane) can be gasified under a fast transient evaporation process cooling the accumulator. On the other hand, the same accumulator can be heated by solar collectors, electrical heaters or by means of evaporated propellants recovering heat losses from fuel cells. To obtain a very high thermal energy storage density, the thermal energy stored in the accumulator is performed using a Phase Change Material (PCM) rounding the different fluid flow tubes which heat or cool the storage tank during periodical cycles. The energy management due to the mismatch between intermittent firings, together with optimum design based on minimum weight with maximum heat transfer capacity has led to developing a numerical simulation model. Thermal and fluid dynamic behavior of multi-physics phenomena in the accumulator is based on coupling the two-phase flow inside tubes working under cryogenic conditions with sensible and latent heat transfer through the tank. The numerical model is divided into: 1) a one-dimensional and transient resolution of the governing equations (conservation of mass, momentum, and energy) for the fluid flow inside ducts; 2) a multi-dimensional and transient resolution of the governing equations in the region occupied by the PCM, incorporating a turbulence model to solve the convection phenomena involved; and 3) a multidimensional and transient treatment of the thermal conduction equation for the solid tubes. The numerical results are validated by means of an experimental cylindrical accumulator test facility, instrumented with 25 thermocouples around the vertical tube which goes through the tank and four multilevel thermocouples columns at different distances radially far from the vertical tube located at the center. The comparative analysis shows a good agreement between both numerical results and experimental data for a wide range of different working conditions showing detailed phenomena analysis, together with the possibilities of this model for design optimization purposes. [ABSTRACT FROM AUTHOR]

This paper presents the main design tradeoffs that should be handled when developing oil-hydraulic Power Take-Off devices aiming at the maximization of energy extraction from waves with a point absorber wave energy converter. These tradeoffs were identified in a case study of a new Power Take-Off concept. The simulation results have shown that improvement of Power Take-Off harvested power is followed by a substantial increase on the power peaks that can be 10 to 30 times above the average power. This demands extreme operational conditions on the Power Take-Off components and an undesirable decrease of overall efficiency. The size of the system, in particular, of the main hydraulic pump, is also substantially increased. Thus, the addition of accumulators, to control the pump size, is recommendable, in particular for storage and release of reactive energy to the Power Take-Off oil-hydraulic cylinders. [ABSTRACT FROM AUTHOR]

Abstract Radial flow pumping rings receive the flow radially which is perpendicular on the shaft while axial flow pumping rings receive the flow in a direction parallel to the shaft (axially). An experimental investigation is carried out to evaluate the single axial pumping ring performance with a non API design radial clearance. The experimental setup is constructed according to API plan 53B with an accumulator-based seal support system in the barrier circuit loop. Furthermore, a numerical investigation is conducted to provide a reliable numerical model represented by ANSYS Fluent by creating an acceptable meshing and turbulence modeling using the experimental results as a validation method. As for the numerical investigation, it is indicated that K-epsilon realizable turbulence model is the best numerical model in terms of the least error deviation between the numerical model's performance curve and the experimental performance curve. [ABSTRACT FROM AUTHOR]

Previous studies have shown the effect of a lead vehicle’s speed, deceleration rate and headway distance on drivers’ brake response times. However, how drivers perceive this information and use it to determine when to apply braking is still not quite clear. To better understand the underlying mechanisms, a driving simulator experiment was performed where each participant experienced nine deceleration scenarios. Previously reported effects of the lead vehicle’s speed, deceleration rate and headway distance on brake response time were firstly verified in this paper, using a multilevel model. Then, as an alternative to measures of speed, deceleration rate and distance, two visual looming-based metrics (angular expansion rate θ ˙ of the lead vehicle on the driver’s retina, and inverse tau τ - 1 , the ratio between θ ˙ and the optical size θ ), considered to be more in line with typical human psycho-perceptual responses, were adopted to quantify situation urgency. These metrics were used in two previously proposed mechanistic models predicting brake onset: either when looming surpasses a threshold, or when the accumulated evidence (looming and other cues) reaches a threshold. Results showed that the looming threshold model did not capture the distribution of brake response time. However, regardless of looming metric, the accumulator models fitted the distribution of brake response times better than the pure threshold models. Accumulator models, including brake lights, provided a better model fit than looming-only versions. For all versions of the mechanistic models, models using τ - 1 as the measure of looming fitted better than those using θ ˙ , indicating that the visual cues drivers used during rear-end collision avoidance may be more close to τ - 1 . [ABSTRACT FROM AUTHOR]

Steel circular hollow section tubes are widely used as tubular structural members, and impact accidents usually occur while these tubes are in their working states. This paper presents experimental studies on axially preloaded circular steel tubes subjected to transverse low-velocity mass impact. A total of 32 impact tests, representing four types of scenarios, are conducted to investigate the influences of preloading and the boundary condition on the structural responses of tubes. An axial force loading system is designed, and a bladder accumulator is adopted in the system to compensate for the axial compressive loading. The test processes of the tubes under transverse impact are described in detail, and four failure modes are identified. All specimens of the four scenario types deformed according to the three-hinge mechanism. Based on the test results, the influence and mechanism of axial force are proposed. The effects of axial tension, axial compression and the boundary condition on the structural behaviour of tubes are discussed. The results show that the axial tension can enhance the bending resistance and lateral collapse capacity of tubes, while the axial compression reduces the collapse capacity significantly. By comparing the responses of tubes under different boundary conditions, the lateral resistance of tubes and the structural response are shown to have a strong correlation with the axial constraint. [ABSTRACT FROM AUTHOR]

This study presents the results of a collective study performed at CETIM for industrials of the hydraulic transmissions profession. The purpose is to develop an accumulator made of composite material, carbon fiber and thermosetting resin, and to characterize the behavior of this accumulator by both static and cyclic pressure tests. Knowledge of the damage mechanisms evolution occurring during these tests is studied by Acoustic Emission monitoring combined by strain gage measurements. The AE monitoring results are compared to the failure criteria used in the design model in order to correlate the different damage mechanisms occurring in each layer with the detected AE signals. Further mechanical tests were carried out on samples taken from accumulators tested at different pressure levels. Visual observations by video camera combined with AE data recording during these tests validated the identification and the progression of the different damage mechanisms in different layers. [ABSTRACT FROM AUTHOR]

An experiment was conducted for the OECD/NEA ROSA-2 Project using the large scale test facility (LSTF), which simulated a cold leg intermediate-break loss-of-coolant accident with 17% break in a pressurized water reactor. Assumptions were made such as single-failure of high-pressure and low-pressure injection systems of emergency core cooling system. In the LSTF test, core dryout took place because of a rapid drop in the core collapsed liquid level before loop seal clearing (LSC). Liquid was accumulated in upper plenum, U-tube upflow-side and inlet plena of steam generators before the LSC because of counter-current flow limiting (CCFL) by high steam velocity, which caused further decrease in the core collapsed liquid level. The post-test analysis by RELAP5/MOD3.3 code revealed that peak cladding temperature (PCT) was overpredicted because of the underprediction of the core collapsed liquid level due to inadequate prediction of accumulator flow rate. We created the phenomena identification and ranking table for each component from the viewpoint of the importance of phenomena in determining the PCT. We found the combination of multiple uncertain parameters including slope m and intercept C of the Wallis CCFL correlation at the upper core plate, core decay power, and steam convective heat transfer coefficient in the core within the defined uncertain ranges largely affected the PCT. [ABSTRACT FROM AUTHOR]

This paper aims to evaluate the effects of coolant injection into a three-loop Westinghouse plant reactor vessel by the accumulators during small break loss of coolant accident, under severe accident condition. Using RELAP5/SCDAP mod3.4 computer code, a best estimate simulation from initiating SBLOCA event of 2, 3, and 4-in. without active part of the emergency core cooling system, in conditions with and without accumulators, is conducted until the rector pressure vessel failure. The results show that, the actuation of the accumulators lead to postponing the reactor vessel failure. Therefore, although the accumulators are designed for a large break LOCA, their actuation is very effective on the delay of a vessel failure. In this paper, the melt core concrete interaction is analyzed using CONTAIN2.0 code for the 4-in. break size without ACCs case as the most serious cases for the time of lower plenum failure. The result for 52.8 h is reported. The in-vessel molten material retention strategy for this case is studied using RELAP5/SCDAP code. The results show that lower plenum integrity is preserved during the severe accident that causes reactor core melt. [ABSTRACT FROM AUTHOR]

The Westinghouse AP1000® reactor is an advanced design whose safety systems are mainly passive safety systems. Due to the passive nature of the safety related systems and its dependency on small changes on certain variables (e.g. pressure, friction coefficients) together with the use of a simplified code like MAAP in Probabilistic Risk Assessment (PRA) analyses, it makes necessary to confirm that when core cooling is achieved, thermal-hydraulic (T/H) uncertainties are bounded. The T/H uncertainty evaluation process performed by Westinghouse Electric Company (WEC) identified the low-margin sequences (core uncovery) by expanding PRA Event Trees (ETs). The expanded ETs allowed finding the low-margin risk-important sequences and then a set of low-margin bounding sequences was selected. Then detailed safety analysis methodologies were applied in order to evaluate the bounding sequences demonstrating that the T/H uncertainties were bounded. The Universidad Politécnica de Madrid group has verified the low-margin bounding sequences obtained by WEC with the best-estimate TRACE code in order to verify the previous results and also to study the phenomenology of such sequences through a best-estimate code. This paper presents the results obtained for short-term low-margin bounding sequences. In general, TRACE results do not present important discrepancies with respect to NOTRUMP and WCOBRA/TRAC results although TRACE presents lower values for Peak Cladding Temperature. This analysis has allowed to verify the AP1000 thermal-hydraulic bounding evaluation process performed by WEC for the low-margin risk-important sequences with TRACE code. [ABSTRACT FROM AUTHOR]

As the development of the nuclear industry, passive technology turns out to be a remarkable characteristic of advanced nuclear power plants. Since the 20th century, much effort has been given to the passive technology, and a number of evolutionary passive systems have developed. Thoughts have been given to upgrade the existing reactors with passive systems to meet stricter safety demands. In this paper, the CPR1000 plant, which is one kind of mature pressurized water reactor plants in China, is improved with some passive systems to enhance safety. The passive systems selected are as follows: (1) the reactor makeup tank (RMT); (2) the advanced accumulator (A-ACC); (3) the in-containment refueling water storage tank (IRWST); (4) the passive emergency feed water system (PEFS), which is installed on the secondary side of SGs; (5) the passive depressurization system (PDS). Although these passive components is based on the passive technology of some advanced reactors, their structural and trip designs are adjusted specifically so that it could be able to mitigate accidents of the CPR1000. Utilizing the RELAP5/MOD3.3 code, accident analyses (small break loss of coolant accident, large break loss of coolant accident, main feed water line break accident) of this improved CPR1000 plant were presented to demonstrate three different accident mitigation methods of the safety system and to test whether the passive safety system preformed its function well. In the SBLOCA, all components of the passive safety system were put into work sequentially, which prevented the core uncover. The LBLOCA analysis illustrates the contribution of the A-ACCs whose small-flow-rate injection can control the maximum cladding temperature effectively. In the MFLB, due to the proper design of the PEFSs, the PRZ was not overfilled by water so that no liquid leakage to the containment happened. Massive radiation release was prevented. Generally speaking, the passive safety system functions as expected, and the three accident mitigation method were proved to be useful for mitigating corresponding accidents. [ABSTRACT FROM AUTHOR]

A fully coupled hydro-mechanical model based on the discrete element method has been built up to characterize the properties of fluid driven fractures. The rock mass is represented by a set of discrete elements interacting through elastic-brittle bonds that can break to form cracks which can coalesce to form fractures. The fluid flow between the elements is computed as a function of the dual pore space deformation in the intact medium and of the cracks' aperture in the fractures through a finite volume scheme. A series of hydraulic fracturing simulations were performed on intact specimens subjected to different loading conditions. The respective contributions of the matrix permeability, fluid compressibility, injection flow rate and state of stress are investigated while the effect of the distance between the perforation clusters, the wellbore-deviation from the minimum principal stress direction and the orientation of the injection slots for multiple injection treatments along a wellbore segment. For the analysis the evolutions of the P 33 (fracture volume) and P 32 (fracture intensity) indices are followed. The results show how, for a single injection treatment, P 33 and P 32 values can be affected by the state of stress inside the medium. Also, they show that aligning the perforation slots with the maximum horizontal stress direction might be a straightforward solution to optimize the opening of the induced fractures. [ABSTRACT FROM AUTHOR]

Mulching with the straws of Trifolium repens, Conyza canadensis and Stellaria media increased the root, stem, leaf, shoot and whole-plant biomasses of Cyphomandra betacea seedlings under cadmium (Cd) stress compared with the control, increased the chlorophyll a, chlorophyll b, total chlorophyll and carotinoid contents, and improved superoxide dismutase, peroxidase, and catalase activities. However, the straw of Eclipta prostrata decreased the biomass, photosynthetic pigment content and antioxidant enzyme activity of Cyphomandra betacea seedlings under Cd stress compared with the control. Mulching with the straws of Trifolium repens, Eclipta prostrate, and Stellaria media increased the Cd contents in roots, stems, leaves, and shoots of Cyphomandra betacea seedlings compared with control, while the straw of Conyza canadensis decreased the Cd content. Therefore, mulching with Conyza canadensis can promote the growth of Cyphomandra betacea seedlings, and decrease their Cd accumulation, which benefits the safe production of Cyphomandra betacea. © 2016 American Institute of Chemical Engineers Environ Prog, 36: 366-371, 2017 [ABSTRACT FROM AUTHOR]

The paper deals with the improvement of central traversing system on rotor spinning machines, where rectilinear motion with variable stroke is used. A new system of traversing rod with implemented set of magnetic-mechanical energy accumulators is described. Mathematical model of this system is analysed in the MSC. Software Adams/View and verified by an experimental measurement on a real-length testing rig. Analysis results prove the enhancement of devised traversing system, where the overall dynamic force is reduced considerably. At the same time, the precision of the traversing movement over the machine length is increased. This enables to increase machine operating speed while satisfying both the maximal tensile strength of the traversing rod and also output bobbin size standards. The usage of the developed mathematical model for determination of the optimal number and distribution of accumulators over the traversing rod of optional parameters is proved. The potential of the devised system for high-performance rotor spinning machines with longer traversing rod is also discussed. [ABSTRACT FROM AUTHOR]

Pneumatic artificial muscles have been known since 1930s. Their advantage is in a simple design and good specific power [Madden 2004, Kocis 2016b]. However, the critical disadvantage is the requirement of an air compressor or a compressed air accumulator. This disadvantage disables the use of pneumatic artificial muscles in mobile robotics. In constrast to pneumatic artificial muscles dielectric elastomer actuators as basic units of artificial muscles are convenient for mobile robots propulsion [O'Brien 2012, Moghadam 2015]. We investigate a new design of pneumatic artificial muscles that can be powered by the energy of electrostatic field. This paper describes the design of a new artificial muscle technology and solves a behavior under small strains. [ABSTRACT FROM AUTHOR]

The Mani peninsula is regarded as a key area of Greece for Palaeolithic studies due to the large number of known excavated sites containing deposits with artifacts and skeletal remains from the Middle and Upper Palaeolithic, revealing the abundance of human occupation in the wider area during the Middle-Late Pleistocene. Melitzia Cave is one of several karstic cavities found on the western coast of Mani peninsula, used as a shelter by Late Pleistocene humans. The Upper Palaeolithic avifauna assemblage recovered from Melitzia Cave has been studied both taxonomically and taphonomically to identify the agent of accumulation, as each predator hunts and consumes its prey in a particular way. The results point to extensive human hunting of rock partridges. A broadening of the dietary sources for humans, known as the Broad-Spectrum Revolution hypothesis, occurred in the Mediterranean after the Last Glacial Maximum and is marked by the hunting of small game such as rabbits and birds. Surface modifications, such as cut marks, peeling and percussion marks, as well as fragmentation patterns indicating the disarticulation of bones, point to human occupants being involved in the modification and disposal of the remains, as they captured the Aves for consumption. Only a few of the bones, bearing digestion or tooth marks, were brought into the cave by non-human predators, indicating that carnivores played a small role in creating and modifying the assemblage as well. This phenomenon enchanted the fact that intensive human occupation and carcass processing lead to a deficiency of carnivores. This study provides further evidence of the exploitation of avian resources by humans during the Upper Palaeolithic in the Eastern Mediterranean. [ABSTRACT FROM AUTHOR]

In the curing process of fiber-reinforced plastic accumulators, a thermal spike appears due to the exothermic reaction of the resin. It is necessary to accurately evaluate this thermal spike to guarantee quality and avoid using a trial and error approach to control the temperature. Thus, we developed a curing process simulator that is able to accurately evaluate the thermal spike of the thermosetting resin. A simplified mesoscale finite element model with the definite separation of fiber and resin is used in the simulation. In this study, the newly developed simulation system was examined by comparing its results with the experimental results from the curing process of fiber-reinforced plastic accumulators. [ABSTRACT FROM AUTHOR]

The passive safety systems of AP1000 are designed to operate automatically at desired set-points. However, the unavailability or failure to operate of any of the passive safety systems will change the accident sequence and may affect reactor safety. The analysis in this study is based on some hypothetical scenarios, in which the passive safety system failure is considered during the loss of coolant accidents. Four different cases are assumed, that is, with all passive systems, without actuation of one of the accumulators, without actuation of ADS stages 1–3, and without actuation of ADS stage 4. The actuation of all safety systems at their actuation set-points provides adequate core cooling by injecting sufficient water inventory into reactor core. The LOCA with actuation of one of the accumulators cause early actuation of ADS and IRWST. In case of LOCA without ADS stages 1–3, the primary system depressurization is relatively slow and mixture level above core active region drops much earlier than IRWST actuation. The accident without ADS stage 4 actuation results in slow depressurization and mixture level above core active region drops earlier than IRWST injection. Moreover, the comparison of cladding surface temperature is performed in all cases considered in this work. [ABSTRACT FROM AUTHOR]

In this paper, a floating-buoy wave energy converter using hydrostatic transmission system is studied. The entire work progress of wave energy power generation device is introduced, and the hydraulic transmission principles are emphasized through the simulation to verify the feasibility of design principle of hydraulic transmission system. The mathematical model of the accumulator is established and applied in the AMEsim simulation. The simulation results show that the accumulator plays an important role in the wave power hydraulic transmission system and that the correct configuration of accumulator parameters can improve the rapidity and stability of the system work. Experimental results are compared with the simulation results to validate the correctness of the simulation results. This would provide a valuable reference to the optimal design of wave power generation. [ABSTRACT FROM AUTHOR]

This work presents the study of the characteristic retention times on Carbosieve SIII adsorbent for several permanent gases CO, CO, CH, N with respect to the temperature of cooling of adsorption accumulators. To perform this work, a laboratory model of a gas chromatograph that included all key components of a standard instrument has been designed. [ABSTRACT FROM AUTHOR]

In this study, the thermo-hydraulic performance of rectangular duct roughened with a new configuration of periodic rib, broken arc rib combined with staggered rib piece on one broad wall is determined for flow Reynolds number range of 2000 to 16000. The roughened wall is uniformly heated while the remaining three walls are insulated. These boundary conditions correspond closely to those found in solar air heaters. The channel aspect ratio was 12. Four broken arc rib combined with staggered rib roughened plates having relative staggered rib position of 0.2, 0.4, 0.6 and 0.8 have been tested. The other roughness parameters such as the relative gap width, arc angle, relative gap position, relative staggered rib size, relative roughness pitch and relative roughness height were fixed as 1.0, 30°, 0.65, 5.0, 10 and 0.043 respectively. The Nusselt number and friction factor is found to be more at relative staggered rib position of 0.6 than at other relative staggered rib positions. The thermo-hydraulic performance is found to be more for relative staggered rib position of 0.6. The highest value of thermo-hydraulic performance is 2.25 corresponding to Reynolds number of 12000, as compared to 1.98 for broken arc rib roughened duct. [ABSTRACT FROM AUTHOR]

This article presents selected results of preliminary tests that were carried out on a four-stroke engine with spark ignition (SI), as well as a mechanical oscillator with pneumatic support - the so-called pneumatic energy accumulator (PAE). This solution is expected to provide a significant improvement in the efficiency of SI engines in a range of partial loads. Due to the self-regulatory properties of the combustion chamber, the engine equipped with this type of oscillator is called an Active Combustion Chambers engine or, in short, an ACC engine. The aim of this study was preliminary to evaluate the possibility of controlling the thermodynamic processes that occur at the end of a compression stroke and at the beginning of an expansion stroke. It also aimed to carry out a preliminary assessment of a simulation model of a PAE (US 872039-B2). This article includes a diagram of an ACC engine with a brief description of the physical model of the oscillator. It also includes the mathematical description that was used for the simulation. As part of the analysis that was carried out, the article presents graphs of the simulation studies and empirical research. [ABSTRACT FROM AUTHOR]

Low overhead error-resiliency techniques such as algorithmic noise-tolerance (ANT) have been shown to be particularly effective for signal processing and machine learning kernels. However, the overhead of conventional ANT can be as large as 30% due to the use of explicit estimator block. To overcome this overhead, embedded ANT (E-ANT) is proposed [S. Zhang and N. Shanbhag, “Embedded error compensation for energy efficient DSP systems,” in Proc. GlobalSIP, Dec. 2014, pp. 30–34], where the estimator is embedded in the main computation block via data path decomposition (DPD). E-ANT reduces the logic overhead to be below 8% as compared with the 20%–30% associated with conventional reduced precision replica (RPR) ANT system while maintaining the same error compensation functionality. DPD was first proposed in our original paper [Zhang and Shanbhag, 2014] where its benefits were studied in the case of a simple multiply-accumulator (MAC) kernel. This paper builds upon [Zhang and Shanbhag, 2014] by 1) providing conditions for the existence of DPD, 2) demonstrating DPD for a variety of commonly employed kernels in signal processing and machine learning applications, and 3) evaluating the robustness improvement and energy savings of DPD at the system level for an SVM-based EEG seizure classification application. Simulation results in a commercial 45 nm CMOS process show that E-ANT can compensate for error rates up to 0.38 for errors in FE only, and 0.17 for errors in FE and CE, while maintain a true positive rate ptp > 0.9 and a false positive rate pfp\leq 0.01. This represents a greater than 3-orders-of-magnitude improvement in error tolerance over the conventional system. This error tolerance is employed to reduce energy via the use of voltage overscaling (VOS). E-ANT is able to achieve 51% energy savings when errors are in FE only, and up to 43% savings when errors are in both FE and CE. [ABSTRACT FROM AUTHOR]

High-quality lead iodide (PbI $$_{2}$$ ) nanoparticles were synthesized from both anode and cathode of a discarded sealed lead-acid accumulator as starting materials. The structure, morphology, chemical composition and optical properties of washed PbI $$_{2}$$ were investigated using X-ray diffraction, field emission scanning electron microscope, photoluminescence and energy-dispersive X-ray spectrometer. The XRD measurements indicated the presence of pure hexagonal PbI $$_{2}$$ nanoparticles. Application of the Scherrer equation indicates crystal sizes between 13.703 and 14.320 nm. SEM indicated the presence of spherical particle agglomerations between 1.5 and 3.5 $$\upmu$$ m in diameter. The measured band gap using two methods was consistent at 2.75 eV. EDS results suggest the absence of impurities in the synthesized nanoparticles. The overall results suggest that discarded sealed lead-acid accumulators can source pure hexagonal-phase lead iodide nanoparticles with potential applications in perovskite solar cells. The novelty aspect is that this approach has not been previously reported. [ABSTRACT FROM AUTHOR]

This research focuses on a sensitivity analysis of accumulators configuration in a Large Break Loss of Coolant Accident (LB-LOCA) in Bushehr Nuclear Power Plant (BNPP). In this way, primary and secondary side components are modeled using RELAP5/MOD3.3 code. Having modeled the BNPP in a steady state hot full power operation, the thermal hydraulic consequences of a LB-LOCA in the reactor inlet is considered and sensitivity analysis for four major different configurations of accumulators are studied in detail. It is shown that any arrangement of accumulators in the Reactor Pressure Chamber (RPC) or Reactor Collection Chambers (RCC) leads to variation of fuel and clad temperatures during the accident and it is important to study the worst condition. Meeting the needs of the safety criteria necessitates tracing of fuel and clad temperatures in short time following the accident in the worst case, emphasizing on the importance of this study. Performance of accumulators when connected to the RCC is also compared to the case of their connection to the RPC and it is shown that the former has a superior efficiency over the latter. Finally, it is proved that in all accumulator arrangements, fuel and clad temperatures do not cross the safety red line despite some variations in the core cooling process following the accident. [ABSTRACT FROM AUTHOR]

How people perceive temporally overlapping intervals can inform us about the architecture and constraints of the human timing system. In the present study, we examined the time perception of two overlapping intervals in a nested context. In this context, one short interval (1 s) was temporally nested within another long interval (3 s). The data showed that although participants' perception of the short interval was unaffected by its temporal position within the long interval, estimates of the long interval decreased, the later the short interval appeared. These data indicate that participants perceive two overlapping intervals as three segments that must be summed in order to estimate the long interval. Importantly, the temporal relationships between overlapping intervals affect the estimates, because a recency weighting is applied to each segment during the summing process. Within pacemaker-accumulator models, these results could be seen as supporting a timing system composed of a single pacemaker and a single accumulator, but they could also constrain any account of human interval timing. [ABSTRACT FROM AUTHOR]

This paper presents an improved input-buffer architecture for the X part of a very large FX correlator that optimizes memory use to both increase performance and reduce the overall power consumption. The architecture uses an array of two-accumulator CMACs that are reused for different pairs of correlated signals. Using two accumulators in every CMAC allows the processing array to alternately correlate two sets of signal pairs selected in such a way so that they share some or all of the processed data samples. This leads to increased processing bandwidth and a significant reduction of the memory read rate due to not having to update some or all of the processing buffers in every second processing cycle. The overall memory access rate is at most 75 % of that of the single-accumulator CMAC array. This architecture is intended for correlators of very large multi-element radio telescopes such as the Square Kilometre Array (SKA), and is suitable for an ASIC implementation. [ABSTRACT FROM AUTHOR]

This paper presents a highly-efficient algorithm for the detection of lines, circles, and ellipses. The algorithm uses a novel method for the determination of candidate curves, and no accumulator is needed to save the information of the related parameters. We first define a curve parameter by random sampling and then calculate the amount of points on the curve after selecting several test points in the test area. If the amount of points on this curve is larger than a certain threshold, the curve is then considered as a candidate curve. Afterwards, the evidence-collecting process will be used to further affirm whether this candidate curve is true or not. A large number of experiments have shown that this new method has the advantage of a faster speed of about one to two orders of magnitude compared with the randomized Hough transform algorithm. Besides, it also has a higher detection accuracy and strong robustness. [ABSTRACT FROM AUTHOR]

The micro-morphology and local mechanical mechanic property parameters of the clad steel plates (304L+533B) used in the accumulator tank of nuclear plant at different temperatures are obtained from the microscopic and macroscopic test. And the monotonic tensile behavior of the clad steel plates and the forming process of the accumulator tank petals are simulated by using the finite element code ABAQUS. Based on the simulations, the validation of the obtained mechanical parameters and the forming safety of the clad steel plates are checked and evaluated. It is shown that the mechanical parameters obtained in this paper are reasonable, and the cold forming process of the rolling clad steel plates (304L+533B) used in the accumulator tank of nuclear plant is safe. [ABSTRACT FROM AUTHOR]