In the present design the anode has a larger bore di- ameter of 70 mm, and a large range of magnetic field val- ues around the anode is available. Two operation modes studied here are diﬀerent in terms of electrical contact be- tween the discharge electrodes in magnetic field. In the first mode later called direct discharge, the magnetic field geometry allows the field lines from the outer region of the cathode to intersect the anode surface. The second dis- tinct operation mode called cross-field discharge, is char- acterized by a finite cathode-to-anode gap across the mag- netic field. In the majority of the experiments this gap was made equal to 1 cm which provided greater degree of magnetic insulation than in the previous experiments . Two operation modes are characterized by diﬀerent dis- charge voltages and plasma density radial distributions. In the cross-field mode the discharge voltage is significantly higher than in the direct discharge mode, and this voltage increases with the magnetic field value. The radial dis- tributions of the plasma density are also diﬀerent in these two modes. The direct discharge mode produces relatively broad and flat-top plasma stream with moderate plasma density, whereas in the cross-field mode the plasma den- sity profiles are almost Gaussian and the peak density at the axis is ≈ 10 13 cm −3 . Thus, by switching the external
A thermodynamic approach to the calculation of ventilation systems operating time in storage facilities of juicy vegetable raw materials basing on the humidity potential theory is suggested. Results of theoretical and experimental studies of the dynamics of heat and mass transfer processes in a layer of stored products are shown. Improving of agricultural products preservation is achieved by optimization of ventilation systems operation modes.
current stresses, conduction losses and ripple performances are uncompetitive compared to other operation modes. Mode B is able to reduce the losses significantly due to its lower current stresses for switches and the decreased total switching actions. Mode C offers maximum control flexibility with both two legs being modulated independently (higher switching losses than mode B). By certain arrangement for the modulating signals, this mode is able to manipulate the converter average model to be a linear form with enhanced global stability and robustness. The UNI-AC also has a common ground shared by the input and output ports. Experimental work has been carried out to verify the feasibility and effectiveness of the UNI-AC.
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The paper is structured as follows. In section 2, we provide an overview of the basic properties of stream ciphers and introduce the terminology used subsequently. In particular, we describe the typical components of stream ciphers employed in practice and distinguish between two different operation modes. In section 3, we then go into details about the inner workings of some prominent stream ciphers, with a focus on their respective state initialization algorithms and how they are operated. Following this, in section 4, we introduce a way of modeling the state initialization and keystream generation of stream ciphers and exemplify this model using the ciphers described in section 3. The resulting insights will finally allow us in section 5 to compare the security (w.r.t. generic collision attacks) of existing approaches for operating stream ciphers to the security of our new design paradigm.
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There are different options for integrating energy storage into a utility-scale solar PV system. Specifically, energy storage can be integrated into the either ac or dc side of the solar PV power conversion systems which may consist of multiple conversion stages –. This paper uses a novel single-stage solar converter called Reconfigurable Solar Converter (RSC). Fig. 1. shows the overall block of the proposed system. The basic concept of the RSC is to use a single power conversion system to perform different operation modes such as PV to Induction Motor drive (dc to ac), PV to battery (dc to dc), battery to Induction Motor drive (dc to ac), and battery and PV to Induction Motor drive (dc to ac) for solar PV systems with energy storage. Section II introduces the proposed RSC circuit and different modes of operation. In Section III, control of the RSC is introduced and necessary design considerations to the conventional three-phase PV converter. Section IV verifies the RSC with simulation using MATLAB / Simulink that demonstrate the attractive performance characteristics. Section V summarizes and concludes the paper.
Jing He et al.  took patents on the system that utilized multiple motors in 2012. The system employed a basic planetary gear train (PGT) as the transmission. The motor is connected to the ring gear, the flywheel is connected to the sun gear, and the output shaft to the carrier. The system comes up with a dual motor for increasing the power and operation modes. The system shows the combination of many motors to regulate energy for controlling series operation modes.
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However, the stated theoretic calculations must be applied to conditions of factual operation of vehicles with combustion engines. To deduce appropriate conclusions and to describe long-term trends of monitored indices developments, it is necessary to determine their trend, that is, to replace the progression of empirical values with a progression of values without a random fluctuation and, thus, to equalize interval time series using a suitable method. For equalizing time series, an analytic equalizing is frequently used in technical routines. This equalizing consists of describing the course of given time series by a simple theoretic and analytic function of the type y = f(t,b) where t is a time variable and b represents a vector of unknown parameters. In principle, this is a simple regression where the time series index features a dependent variable and time (time variable) an independent variable. To determine the “best” values of parameters, the minimum of sum of deviations (residua) squares of the measured and calculated magnitudes of a dependent variable is used as a regress criterion in technical routines most often.
For a complete switching cycle of the proposed converter, there are three modes of operation in the positive half cycle of the supply voltage. In first mode of operation, the switch Sw1 conducts to charge the inductor Li1 and this increases the inductor current iLi1 as shown in Fig. 2(a). Diode Dp completes the input side circuitry, and the dc link capacitor Cd is discharged by the VSI-fed BLDC motor. In second mode of operation, switch Sw1 is turned off, and the transfer of stored energy in inductor Li1 takes place to dc link capacitor Cd until the inductor is completely discharged. The current in inductor Li1 decreases till it reaches zero. In third mode, no energy is left in the inductor Li1 and hence, it enters discontinuous conduction, i.e. current of Li1 becomes zero for the rest of the switching period. At this time, as shown in Fig. 2(c), both switch and diode are not conducting, and energy is supplied to the load via dc link capacitor Cd; hence, voltage Vdc across dc link capacitor Cd starts to decrease. The operation is repeated when switch Sw1 is turned on again after a complete switching cycle. Similarly, during the negative half cycle of the supply voltage, switch Sw2, inductor Li2, and diodes Dn and D2 operate for voltage control and PFC operation.
While in the batch mode this ratio is easily controlled, in the continuous operation it is much more difficult to set the proper material flows. Of particular importance is to set acceptable limits for the ratio, as the dosage pumps have their own tolerable deviations. It is necessary for the bitumen to PR ratio to be within the set interval of deviation. Process conditions
Scaling as one of the most important challenges from the technology viewpoint. The channel length of Field Effect Transistors (FETs) has passed from micrometers to tens of nano meters. However, drawbacks of scaling have the increase of short channel, parasitic, reliability and variability effects. To overcome the problems related to scaling, new transistor architectures have to be investigated. FinFET is the most promising double-gate transistor architecture to extend scaling over planar device. Multiple gates have better control over the SCEs. Particularly the FinFET technology provides superior scalability of the DG-MOSFETs compared to the planar MOSFET. Fin-FETs are predicted as one of the best possible candidates to replace the bulk MOSFETs. The FinFET technology power consumption compare with the CMOS technology. The two gates of a FinFET can either be shorted for higher performance or independently controlled for lower leakage or reduced transistor count. Analyzed different type of operation mode like Shorted Gate, Independent gate, and Low power mode.
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distributed energy storage elements, electrical distribution gear and controllable loads. DPG modules are critical components within the micro grid systems and need to have flexible features in order to respond for a wide range of applications. DPG are designed to operate in islanded mode, utility grid-connected or genset-connected (diesel, liquid propane generators). DPG converter modules may have the following modes of operation: voltage-controlled source, current controlled source, active rectifier and active power filter mode. The converted energy produced can be delivered to the local loads within the micro grid structure or exported to the utility grid. In active rectifier mode, with ac to dc energy conversion the DG has a multi loop embedded control with power factor correction and dc voltage and current are controlled typically for battery charging . In active power filter mode selective ac current harmonics are generated to cancel out the load current harmonics from the funda mental line frequency . PV inverters are typically DPG operating in current controlled mode, with dc to ac energy conversion where ac current is controlled in magnitude and phase , . Transformerless PV inverters represent an attractive solution due to higher efficiency, smaller size and weight, reduced cost , .
The flexibility of the controller allows the energy harvesting circuit to be used on any vibrating structure, regardless of excitation frequency, provided a piezoelectric element can be attached. Also, external parameters such as device placement, level of mechanical vibrations or type of piezoelectric devices will not affect controller operation. The control algorithm can also be applied to other dc–dc converter topologies. This would allow the development of optimized system designs based upon the expected excitation or the electronic load that was to be powered and because the system was designed to be self-powering, no external power supply was needed, making the system suitable for remote operation. Future work will focus on the design of an optimized system design using standalone control circuitry.
Fig.2- shows the PFC Cuk converter based VSI fed BLDC motor drive using a current multiplier and a voltage follower approach respectively. A high frequency metal oxide semiconductor field effect transistor (MOSFET) is used in Cuk converter for PFC and voltage control, whereas insulated gate bipolar transistor’s (IGBT) are used in the VSI for its low frequency operation. BLDC motor is commutated electronically to operate the IGBT’s of VSI in fundamental frequency switching mode to reduce its switching losses. The PFC Cuk converter operating in CCM using a current multiplier approach is shown in Fig4.1; i.e. the current flowing in the input and output inductors (Li and Lo), and the voltage across the intermediate capacitor (C1) remain continuous in a switching period. The current flowing in either of the input or output inductor (Li and Lo) or the voltage across the intermediate capacitor (C1) become discontinuous in a switching period for a PFC Cuk converter operating in DCM. A Cuk converter is designed to operate in all three discontinuous conduction modes and a continuous conduction mode of operation and its performance is evaluated for a wide voltage control with unity power factor at AC mains.
In this paper, the different modes of operation of a power conditioner system to improve the power quality of the distribution grid are presented. With the energy storage integration, the DVR portion of the power conditioner will be able to independently compensate voltage sags and swells and the APF portion of the power conditioner will be able to provide active and reactive power support, renewable intermittency smoothing and harmonic compensation to the distribution grid. UCAP is integrated through a bi-directional dc-dc converter at the dc-link of the power conditioner. The control strategy of the series inverter (DVR) is based on the in-phase compensation and the control strategy of the shunt inverter (APF) is based on the i d -i q method. Average current mode control is used to regulate the output voltage
Abstract: Cryptography is the science of secret codes. Previously we used DES algorithms in order to secure but cannot encrypt completely. Thus, we referred AES Algorithms to create a ciphertext in encryption and is given as an input in decryption. In present scenario, everyone sharing their data in online using internet alsoonline transactions like e-banking for money transfers, in shopping malls, restaurants, and many more. While transferring a huge amount or any confidential data there are many chances to hack the data.There are different modes of operations used in AES in accordance with the efficiency to blur the data. The design has been done in VHDL (Very High-Speed Integrated Circuit Hardware Description Language) and simulated and synthesized using Xilinx.
Based on the above meta-theorem, we implemented a model checker designed to evaluate candidate modes of operation. Our model checker takes as input a mode specified as a graph, and determines both whether the mode is correct (i.e., whether there exists a corresponding decryption algorithm that recovers the message from the ciphertext) and whether it is secure. We then use our model checker to synthesize secure modes of operation in the natural way. That is, we implement a program synthesizer that automatically generates candidate modes of operation for analysis, and then filters out those modes that are not identified as being secure by our model checker. Doing this in a na¨ıve manner would be prohibitively slow due to the combinatorial explosion in the number of candidate modes. To deal with this, we use several pruning strategies that allow us to eliminate more than 99.99% of potential candidates from consideration before invoking our model checker. Using our approach we are able to synthesize hundreds of secure modes of operation. Our implementation could easily be integrated with a simple tool assigning scores to different modes (e.g., expressing a preference for minimizing calls to the block cipher or for avoiding integer addition) to synthesize secure modes with desired properties.
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The design of countermeasures towards SCA attacks is a widespread research area. Contributions in this regard fall into 3 classes: Hiding, masking and Leakage Resiliency. Our attention on this project is to layout a countermeasure for hardware cryptographic modules at a small implementation price (place and overall performance). Hiding relies upon on breaking the hyperlink between intermediate variables and the observable leakage by means of minimizing the sign-to-noise ratio inside the hint. This could be executed the usage of balanced circuits and/or noise turbines. Lamentably, cryptographic modules with hiding require greater than double the region (see ). Overlaying relies upon on breaking Eve’s potential to calculate hypothetical intermediate variables, by means of splitting the useful facts into n shares based on random variable(s). The random variables are generated on-the-fly and discarded afterwards. Every share is processed independently. Despite the fact that leakage resilient primitives may be implemented using unprotected cores, the normal overall performance is at least halved (see ). Maximum contributions in leakage resiliency focused on designing new cryptographic primitives – but, the proposed answers have been computationally extensive and do not clear up the hassle of the present day cryptographic schemes. Different contributions focused on assisting a modern-day primitive with an SCA-at ease key-updating scheme (as reviewed in Sec. IV). The contribution on this project follows the latter method. We propose a heuristically SCA-at ease key-updating scheme for the hardware implementation of AES jogging in any mode of operation. We recognition on accomplishing a valid safety on the smallest implementation price
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The scheme of the travelling wave window can be explained by Fig.4. Two windows (shown by violet cuffs) and one or two mirrors form a ring resonator with a travelling wave. The system has zero reflections at the resonant frequency. At non-resonant frequencies some reflection from the cavity occurs, but the reflected wave does not propagate in backward direction and does not disturb the gyrotron operation. Additionally the window unit is transparent for the frequencies where the discs are transparent. The ring cavity
For a consistent power transfer between the system associated operation and islanded mode, different operational changes are included, for example, exchanging between the current and voltage control mode, vigor against the islanding detection and reconnection delays. Obviously, these further increment the control intricacy of the μG systems. To stretch out the operational adaptability and to enhance the power quality in system associated μG systems, over again position and incorporation technique of UPQC have been proposed, which is named as UPQCμG. In the UPQCμG coordinated appropriated system, μG system (with capacity) and shunt some portion of the UPQC are set at the Point of Common Coupling (PCC).
the number of customers at the moment t + 0 then the mode of the system in force at t + 0 is same as that was in t 0. The switchover time between modes is assumed to be negligible. The model under study is described diagrammatically in the following figure below.