Power Consumption Efficiency Research Articles

New class of composite anion exchange membranes based on Quaternized poly (phenylene oxide) and functionalized boron nitride

Anion exchange membranes (AEM) are very important for water desalination and sustainable energy conversion devices. For the synthesis of AEM, carcinogenic chemicals were used, which are banned in India. So based on the requirement quaternized poly (phenylene oxide) (QPPO) based composite membranes has been synthesized in combination with functionalized boron nitride (f-BN). Membrane properties are tuned by varying f-BN content in QPPO. Composite membranes are characterized by means of their water content, ion exchange capacity and ionic conductivity. Additionally, thermal and mechanical properties are also evaluated. BPO-5 membrane displays 1.92 meq/g ion exchange capacity and 6.29 × 10–3 S/cm ionic conductivity. The power consumption and current efficiency during salt removal for BPO-5 membrane is found to be 1.96 kWh/kg and 96.26%, respectively. Among all membranes, BPO-5 exhibits excellent thermal and mechanical stability. BPO-5 membrane show lower power consumption, with high current efficiency during salt removal and better electrochemical selectivity.

Modification of Citric Acid Technology Using Electrodialysis

Modification of conventional citric acid technology has been proposed. Calcium citrate was converted into sodium citrate, which then went through electrodialysis with a bipolar membrane. The electrodialysis was carried out using the following membranes produced by Tokuyama Corporation (Japan): bipolar Neosepta BP, anion-exchange Neosepta ACM, cation-exchange Neosepta CMX; as well as the membranes produced by FumaTech GmbH (Germany): bipolar FBM, anion-exchange FAB and cation-exchange FKB. It was found that there are important relations between current efficiency, current density and energy consumption. The comparison of commercially available membranes shows that the FumaTech GmbH membranes are better - they have a higher efficiency and lower electric power consumption. Moreover, in case of the Tokuyama Corporation membranes, a considerable increase in solution temperature occurred when current density was high. After electrodialysis the acid solution went through crystallisation, which resulted in a product of chemical purity and granulometric composition meeting the criteria of food industry.

Low cost UV sensor using ZnO nanorods on ITO electrodes

Ultraviolet (UV) sensors have gained a lot of importance in the field of environmental sciences, due to their pollution monitoring applications. The current limitations of the UV sensors are their higher temperature operability resulting in high power consumption, degradation and low efficiency. Hence an attempt was made to fabricate room temperature (RT) operable, UV index sensors, using ZnO nanorods on Indium Tin Oxide (ITO) electrodes. The nano rods were grown using hydrothermal method with an optimized concentration and growth duration of 5 mM and 3 h respectively. The vertical rods with a hexagonal face, showed an aspect ratio of six, with weak quantum confinement and a strain of the order of ∼0.002. Nanorods were polycrystalline with an average crystallite size of 50 nm. The broad emission spectra were mostly seen in blue region, with transitions due to singly and doubly ionized zinc interstitials, whose concentration increased with increase in growth duration. The UV response in direct sunlight gave a sensitivity of 118, with rise time and fall time of 35 s and 65 s respectively. The experiments not only yielded reproducible results but the UV index profile for the sensor in response to sunlight, over a full day was in accordance with the profile of the standard WHO sensor. This is of great significance especially from the point of view of ozone depletion, health concerns like skin cancer and environment pollution.

Design and optimization of nitrogen expansion liquefaction processes integrated with ethane separation for high ethane-content natural gas

Compared to ordinary natural gas, ethane has higher market value. Thus, recovery of ethane can increase the economic value of high ethane-content natural gas. This paper proposes a new liquefaction method for high ethane-content natural gas. Natural gas liquefaction and cryogenic distillation are combined to separate high-purity liquid ethane (no less than 99.95%) in the process of producing liquefied natural gas (LNG), which maximizes the economic benefits. And self-supply of the required heat of the distillation column is achieved by heat integration. For this new method, three nitrogen expansion processes are designed, and each process is simulated and optimized by HYSYS and genetic algorithm. Based on the optimization results, the specific power consumption and exergy efficiency of the three processes are analyzed. The results show that the specific power consumption of the three processes decrease with the increase of the ethane content. When the ethane content is 10% ~ 40%, the specific power consumption of the three processes is 0.5969 ~ 0.6060 kWh/Nm3 (NG), 0.5371 ~ 0.5592 kWh/Nm3 (NG), 0.5015 ~ 0.5403 kWh/Nm3 (NG), respectively, and the exergy efficiency of the proposed three processes is 33.3 ~ 35.4%, 37.1 ~ 38.3%, 39.7 ~ 39.9%, respectively.

Energy efficiency and latency analysis of fog networks

The industry of cellular networks is evaluating the new architectures to ensure an enhanced performance. Fog communication is the new paradigm that presented to unleash edge computing. In this paper, we introduced a mathematical framework to evaluate the trade-offs of Fog proposal. Specifically, testing the power consumption, delay and energy efficiency in comparison with traditional cloud radio access networks. Although the literature has showed that fog radio access networks provides an enhanced delay performance, this paper shows that an enlarged amount of power is consumed, which degrades the energy efficiency in comparison with traditional cloud counterpart. However, the level of such devolution depends on the number of deployed fog devices that directly influences the power consumption. This paper also shows that enhancing the delay by using fog architecture is not a straight forward process, but requires a particular caring in terms of choosing the appropriate mode while placing/installing fog functions within fog devices.

Power-saving airlift bioreactor with helical sieve plates: Developmental and performance studies

This study investigated the influence of the geometry of the draft tube on the mass transfer and energy efficiency in the airlift reactor with helical sieve plate (ALR-HSP). The power consumption efficiency was 46%–53% higher than the control condition by optimizing the draft tube. A set of empirical equations was used to describe the gas holdup and volumetric mass transfer coefficients corresponding to the geometry of draft tubes in the ALR-HSP for the water–air system. The comparative cultivation of Pichia pastoris was carried out using the ALR-HSP and the conventional airlift reactor (CALR). The biomass increased by 20%, the maximal specific growth rate during the logarithmic growth phase nearly doubled, and volumetric oxygen transfer coefficient increased by 21%–47% under the same culture conditions. Results preliminarily demonstrated the superior performance and practicability of the ALR-HSP in enhancing oxygen transfer efficiency and aerobic biological reaction efficiency.

Steam generation system operation optimization in parabolic trough concentrating solar power plants under cloudy conditions

Parabolic trough concentrating solar power with indirect thermal energy storage, as a promising application of solar energy, has been widely used in concentrating solar power plants. The exergy efficiency of thermal energy storage system and plant parasitic power consumption could change under cloudy conditions when the thermal oil distribution was adjusted to the live steam branch and reheat steam branch. However, the operating condition optimization of steam generation system has received insufficient attention. This study designed a detailed fixed-power-supply model of parabolic trough concentrating solar power plants to optimize the operation strategies under various conditions. The parametric constraints, which worked on the optimization, were investigated under various direct normal irradiation values. Simulation results indicated that the low reheat steam temperature, thermal oil mass flow rate of the live steam branch, and live steam pressure reduced the molten salt temperature at the discharging exchangers and plant parasitic power consumption. The distribution mode of preferentially satisfactory distribution of reheat steam branch demand had low molten salt consumption and high exergy efficiency of thermal energy storage. The molten salt consumptions under optimal conditions were 0.98%–13.68% lower than the consumption under original conditions with the decreasing direct normal irradiation from 300 W/m2 to 210 W/m2.

Optimization Design of CRC Circuit in UHF RFID Tag Baseband

Aiming at the requirements of EPC Class1 Generation2 (EPC C1G2) and the GB/T 29768 Information Technology Radio Frequency Identification 800/900MHz Air Interface Standard, the paper presented an optimization design of CRC Circuit in UHF RFID Tag baseband. First, the principle of CRC and RFID tag baseband structure are described; To optimize the power consumption and work efficiency of the cyclic redundancy check (CRC), the CRC unit is designed by parallel calculation and circuit multiplexing, then RTL-level coding and function simulation are carried out for the CRC unit; At last, using the SMIC 0.18μm process library to synthesize the logic circuit. The experimental results show that the optimized design is superior to the traditional serial circuit. The hardware area is reduced by about 29%, the timing is reduced by about 22.3% and the total dynamic power consumption is reduced by a small amount.

A comprehensive review on emerging artificial neuromorphic devices

The rapid development of information technology has led to urgent requirements for high efficiency and ultralow power consumption. In the past few decades, neuromorphic computing has drawn extensive attention due to its promising capability in processing massive data with extremely low power consumption. Here, we offer a comprehensive review on emerging artificial neuromorphic devices and their applications. In light of the inner physical processes, we classify the devices into nine major categories and discuss their respective strengths and weaknesses. We will show that anion/cation migration-based memristive devices, phase change, and spintronic synapses have been quite mature and possess excellent stability as a memory device, yet they still suffer from challenges in weight updating linearity and symmetry. Meanwhile, the recently developed electrolyte-gated synaptic transistors have demonstrated outstanding energy efficiency, linearity, and symmetry, but their stability and scalability still need to be optimized. Other emerging synaptic structures, such as ferroelectric, metal–insulator transition based, photonic, and purely electronic devices also have limitations in some aspects, therefore leading to the need for further developing high-performance synaptic devices. Additional efforts are also demanded to enhance the functionality of artificial neurons while maintaining a relatively low cost in area and power, and it will be of significance to explore the intrinsic neuronal stochasticity in computing and optimize their driving capability, etc. Finally, by looking into the correlations between the operation mechanisms, material systems, device structures, and performance, we provide clues to future material selections, device designs, and integrations for artificial synapses and neurons.

Optical GFDM: an improved alternative candidate for indoor visible light communication

This paper proposes generalized frequency division multiplexing (GFDM) for indoor visible light communication (VLC). GFDM is a flexible multi-carrier scheme that allows engineering in both time and frequency domain, therefore, making GFDM suitable for various 5G applications. In the literature, different types of optical orthogonal frequency division multiplexing (O-OFDM) have been proposed for VLC including direct current offset optical OFDM (DCO-OFDM), asymmetrically clipped optical OFDM (ACO-OFDM), Flip-OFDM, etc. O-OFDM can provide high data rate, but it suffers from the problem of the high peak-to-average power ratio (PAPR) which causes clipping distortion, reduces the illumination-to-communication conversion efficiency and affects the lifetime of the LED. The proposed optical GFDM (O-GFDM) scheme for VLC is analyzed for various performance metrics against the O-OFDM counterpart. The analytical expression for symbol error rate (SER) of O-GFDM is derived and simulation results based on PAPR, SER and subcarrier frequency shift tolerance validate the improved performance of the proposed O-GFDM scheme. It is found that one of the variants of the proposed scheme has better spectral efficiency and lower power consumption compared with O-OFDM counterpart. As GFDM is being considered for 5G wireless systems, it is expected that the GFDM-based VLC system will very well gel with next-generation wireless systems to offer seamless services and will provide greater flexibility using software-defined networking.

Electric Power Consumption and Current Efficiency of Electrochemical and Electrobiological Rotating Disk Contactors Removing Nutrients from Wastewater Generated in Soil-Less Plant Cultivation Systems

The study was conducted in a one-stage rotating electrobiological disk contactor (REBDC) and a rotating electrochemical disk contactor (RECDC). Synthetic wastewater with characteristics similar to the wastewater from soil-less cultivation of tomatoes was used in the experiment. Current efficiency (CE) values, that express the denitrification performance of bio- and electrochemical reactors, were higher in the electrobiological contactor than in the electrochemical one. Combining biological processes with electrochemical processes in the electrobiological contactor resulted in almost 20% higher current efficiency in the contactor operated at a density of 0.63 A/m2 and hydraulic retention time (HRT) = 4 h. The study showed that, in both the electrochemical and the electrobiological contactor, current density increase and hydraulic retention time extension increased electric power consumption (E) during phosphorus compounds removal and simultaneously lowered current efficiency.

ВЛИЯНИЕ ВЫСОТЫ СЛОЯ ШЛАКА НА КПД ДУГ И РАСХОД ЭЛЕКТРОЭНЕРГИИ В ДУГОВЫХ СТАЛЕПЛАВИЛЬНЫХ ПЕЧАХ

Investigated the influence of the height of the slag layer in the nomenclature row EAFs, with a capacity from 0.5 to 120 tons, on the efficiency of arcs and specific power consumption in the furnaces. It was found that with an increase in the height of the slag layer, the efficiency of arcs in low-tonnage and heavy-duty furnaces increases and reaches 78…80 % when the arcs are completely immersed in the slag, and the specific power consumption decreases. With an increase in the height of the slag layer and an increase in the efficiency of arcs by 1%, the specific power consumption in the furnaces decreases by 0.75…1.0 %.

An Optimal Energy Efficiency of a Two-tier Network in Control-Data Separation Architecture

In this paper, we propose to maximize the Energy Efficiency (EE) of a two-tier network by jointly optimizing the number of active small cell base stations (SBSs) and the user-cell association. We apply the concept of signaling and data separation where a macro cell base station (MBS) provides full coverage while the SBSs provide high data transmission. First, we model the spatial distributions of the SBSs and mobile users following two independent Poisson Point Processes (PPP) and derive the expressions for the Signal-to-Interference Ratio (SIR), user cell associations, power consumption and energy efficiency of the Heterogeneous Network (HetNet). Then, we formulate the EE maximization problem and solve it by proposing the Switching off Decision and User Association (SODUA) algorithm. The algorithm associates a mobile user to an SBS that offers the highest SIR and calculates the load of each SBS. The algorithm, then, decides to switch off the SBSs that have fewer mobile users than a threshold value, where the mobile users will be offloaded to a nearby SBS that offers the highest SIR. Finally, we calculate the EE of the HetNet. We compare the EE achieved by the proposed algorithm (i.e. after offloading) and that "without offloading". The results show that the proposed algorithm improves the EE of the HetNet and that the EE cannot be further improved by switching off more SBSs than a certain number.

A Comparison between Si and SiC MOSFETs

The Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) has developed quickly and become one of the most important devices for a wide range of applications. There is an increasing need for power MOSFET devices with low power consumption and high energy efficiency. Silicon (Si) and Silicon Carbide (SiC) are two kinds of materials used in power MOSFET devices, which have their own advantages of performance for each use. This paper makes a comparison of the on-resistance and high-temperature performance between Si and SiC MOSFETs. The analysis of the differences between the two will mainly come out from the perspective of material properties, and the conclusion of what is the ideal material for power MOSFET devices will be finally drawn.

Optimum Functional Splits for Optimizing Energy Consumption in V-RAN

A virtualized radio access network (V-RAN) is considered one of the key research points in the development of 5G and the interception of machine learning algorithms in the Telecom industry. Recent technological advancements in Network Function Virtualization (NFV) and Software Defined Radio (SDR) are the main blocks towards V-RAN that have enabled the virtualization of dual-site processing instead of all BBU processing as in the traditional RAN. As a result, several types of research discussed the trade-off between power and bandwidth consumption in V-RAN. Processing at remote locations instead of BBU reduces mid-haul bandwidth at the expense of power consumption and vice versa. As a result, the integration of NFV and SDR in V-RAN facilitates dynamic power consumption and processing whenever relaxation is needed. This paper studies several functional splits proposed by ETSI in the NFV of the dual-site network. In addition, network performance is analyzed in terms of data rate, power consumption, and energy efficiency (EE) optimization. Furthermore, the combined optimization of power consumption and mid-haul bandwidth are investigated, and optimal operating parameters are recommended for similar network operators. Thus, regulators/operators can adjust their networks with these parameters to achieve the best performance. Additionally, the UEs switching scheme is introduced to sleep some RRHs in low-density traffic to lessen power consumption.

Analysis and Modeling of Power Consumption Modes of Tunnelling Complexes in Coal Mines

The technological processes of mining enterprises are largely energy-intensive; therefore, studying the modes of power consumption in different sites of a mining enterprise is a relevant task, as it makes it possible to reduce current costs. The article presents the results of an experimental study of the dynamics of changes in the specific power consumption depending on per-shift indicators of extracted rock volume and the rate of mine workings penetration. The analysis of geological, technological and organizational factors affecting the efficiency of mining operations in coal mines is performed. Energy technological profiles and recommendations for assessing sustainable levels of power consumption by mechanized tunnelling complexes are given. Dynamic and predictive models of power consumption have been developed taking into account the main time trends and additive components within the limits that ensure a steady level of power consumption. Special recommendations on improving the efficiency of power consumption during mining operations are given.

Data Acquisition and Alert System for Recirculation Aquaculture System (RAS) using Fog Computing

This research presents an improved and more effective approach for data acquisition of recirculation aquaculture system (RAS). The previous research, the system uses manual methods to take the important data from RAS and it wastes the time and also gets late response from the fish farmer if the data is not in the good condition. As a result, fog computing technology is applied to overcome all these problems and acts as advance data acquisition system to keep data safely by sharing the processed data in fog computing for every tanks and analyze the data to make an accurate control/decision in the real time. Besides, open source technology plus embedded system based will be integrated for this research because its benefits such as small size, low cost, light weight, portable, high efficiency and low power consumption. This research has achieved the objectives which are design a data collecting system for RAS, design a data processing system using fog computing and integrate, test and validate automatic data collection and processing strategy for recirculation aquaculture system (RAS). The data collecting system for RAS, RaspDAQ is developed by connecting Raspberry Pi 3 to temperature sensor (LM35DT) using analogue digital converter (ADC) MCP3002, water level sensor (HC-SR04), Rpi camera module, LEDs and buzzer. Software and program are built using Python and Apache server to run every functions of RaspDAQ. While third Raspberry Pi 3 is setup as data processing system, RaspFog using PHP, Apache and MySQL server. Both RaspDAQ and RaspFog are based on Raspbian operating system. After that, RaspDAQ1 and RaspDAQ2 are connected to RaspFog using WiFi technology to send sensors data in real time. The received data are stored and plotted using Highcharts.com graph. The data collecting system, RaspDAQ and data server and processor, RaspFog has been tested and validated. At the same time, users can see the graph output in the real time for temperature, water level sensor and real condition using Rpi camera module of RaspDAQ1 and RaspDAQ2 by browsing RaspFog website. From the observation, data has been transferred from RaspDAQ to RaspFog in a short duration which is less than 15 seconds. Consequently, the efficiency of data acquisition process has been improved from manual system to fog computing technology successfully.

Efficient training and design of photonic neural network through neuroevolution.

Recently, optical neural networks (ONNs) integrated into photonic chips have received extensive attention because they are expected to implement the same pattern recognition tasks in electronic platforms with high efficiency and low power consumption. However, there are no efficient learning algorithms for the training of ONNs on an on-chip integration system. In this article, we propose a novel learning strategy based on neuroevolution to design and train ONNs. Two typical neuroevolution algorithms are used to determine the hyper-parameters of ONNs and to optimize the weights (phase shifters) in the connections. To demonstrate the effectiveness of the training algorithms, the trained ONNs are applied in classification tasks for an iris plants dataset, a wine recognition dataset and modulation formats recognition. The calculated results demonstrate that the accuracy and stability of the training algorithms based on neuroevolution are competitive with other traditional learning algorithms. In comparison to previous works, we introduce an efficient training method for ONNs and demonstrate their broad application prospects in pattern recognition, reinforcement learning and so on.

FPGA-based led intensity controller for power consumption efficiency in motorcycle

Improper beam patterns on vehicle lights have major implications for the level of driving safety. This beam pattern control technique has been developed to improve driving safety. Most of them use additional components that increase power costs. In LED-based light sources, the design of LED arrays can increase the level of lighting and expand the transmission area. A large transmitting area is needed, but in a turn of the road, conditions are only needed based on the direction of the vehicle. Therefore, in this study, a system was designed to regulate LED beam patterns based on the direction of the vehicle. The main objective is to reduce power consumption so that it is more environmentally friendly and supports green technology programs. The control process was done by adding control components that work based on the direction of the vehicle that is read by the direction sensor. The digital control algorithm was implemented on the Altera DE-0 Nano FPGA with controls using fuzzy logic. The memory resources needed for implementing this system are 145 logic in the form of the loop up tables and 102 registers with a total power of 2 mW. This control module is able to provide a better focus of lighting and power efficiency up to 53% compared to a system without control.

Characterization of Biodiesel Obtained from Vegetable Oil; Conventional and Residual

This work shows the description of biodiesel production, characterization and tests of performance on a diesel engine, using conventional vegetable oil and residual vegetable oil to generate it. The process to obtain the biodiesel by transesterification is described and three characteristics of both types of biodiesel were determined: pH, density, viscosity and electrolytic conductivity. Then, biodiesel is characterized electromechanically, through the performance of the biodiesel in a diesel engine, whose characteristics are acquired from a test bench where its efficiency in power, torque and energy consumption is determined. Finally, the comparison of the two types of biodiesel is made in order to define the biodiesel with the best characteristics.