Limited Energy Consumption Research Articles

Design of the Central Solenoid of the HV Electron Cooling System for the NICA Collider

The HV electron cooling system designed at the Budker Institute of Nuclear Physics for the NICA collider is the world’s only setup developed for a collider and makes it possible to simultaneously cool two ion beams with an energy up to 4.5 GeV/u using the magnetized electron flow [1]. Due to the fact that the cooling system should be installed at the NICA collider, the distance between the beam axes of cooling channels corresponds to the distance between collider beams and amounts to 320 mm. This became the first factor affecting the entire structure of the electron-cooling system and limits the maximum possible outer radius of longitudinal field coils. The energy-consumption limitation of 500–700 kW [2] can be considered the other factor, and it directly affects the density of filling the solenoid with the conductor. The design of the central solenoid (cooling solenoid) of the electron-cooling system is described, and it has been developed taking into account the imposed limitations.

Energy recovery system in small reverse osmosis desalination plant: Experimental and theoretical investigations

The shortage of potable water, especially in developing countries has attracted researchers to try and overcome this problem. Desalination is one of the most effective methods used to solve this problem. Among desalination techniques, Reverse Osmosis (RO) has higher priority than thermal desalination methods, on account of its comparatively limited energy consumption. Different methods were introduced to enhance the performance of RO desalination plants. This study focused on employing an Energy Recovery System (ERS) to enhance the performance of the small RO plant for remote areas. The unit capacity was 2.4 m3/day, occupied with two double-acting cylinders with their control elements working as an ERS. An experimental setup is used to verify the effectiveness of the proposed ERS. A simulation model is designed and implemented to enable changing system parameters of the plant. The different system pressure experimental and model results were exposed and compared. The obtained results showed good agreement between experimental and simulation model values. The effect of recovery ratio on the power saving is highlighted. The ERS saved power consumption by 80%. The cost analysis of the small RO desalination plant with and without ERS was evaluated and showed a significant reduction in total cost.

Performance analysis of iterative linear regression‐based clustering in wireless sensor networks

Clustering, an energy efficient approach is preferred in wireless sensor network due to the limited energy consumption of sensor nodes. Clustering saves energy as the communication is restricted to a few nodes, thereby increasing the network lifetime. Recently, an iterative linear regression-based clustering is proposed to improve the cluster quality in a wireless sensor network. The quality of clusters so obtained is evaluated through Matlab using the cluster validity analysis platform. However, the performance of the clusters so obtained using iterative linear regression in terms of energy efficiency is not dealt. Hence, an attempt is made to investigate the performance of the network through real time experiments. The network performances are studied in terms of intra-cluster and inter-cluster energy consumption, first node death, half node death and last node death. To prove the effectiveness of the proposed technique, it is compared with the standard k-means clustering algorithm. The results reveal that the clusters obtained using iterative linear regression is efficient in enhancing the lifetime of the wireless sensor network.

Impact of drone route geometry on information collection in wireless sensor networks

The recent technological evolution of drones along with the constantly growing maturity of its commercialization, has led to the emergence of novel drone-based applications within the field of wireless sensor networks for information collection purposes. In such settings, especially when deployed in outdoor environments with limited external control, energy consumption and robustness are challenging problems for the system’s operation. In the present paper, a drone-assisted wireless sensor network is studied, the aim being to coordinate the routing of information (among the ground nodes and its propagation to the drone), investigating several drone trajectories or route shapes and examining their impact on information collection (the aim being to minimize transmissions and consequently, energy consumption). The main contribution lies on the proposed algorithms that coordinate the communication between (terrestrial) sensor nodes and the drone that may follow different route shapes. It is shown through simulations using soft random geometric graphs that the number of transmitted messages for each drone route shape depends on the rotational symmetry around the center of each shape. An interesting result is that the higher the order of symmetry, the lower the number of transmitted messages for data collection. Contrary, for those cases that the order of symmetry is the same, even for different route shapes, similar number of messages is transmitted. In addition to the simulation results, an experimental demonstration, using spatial data from grit bin locations, further validates the proposed solution under real-world conditions, demonstrating the applicability of the proposed approach.

A new class of LT-based UEP rateless codes for satellite image data transmission

Satellite communication systems with the long transmission distance, dynamic channel states and limited energy consumption properties. To improve the image data transmission efficiency in the satellite communication systems, a class of rateless codes which can provide unequal error protection (UEP) property and equal water-fall region performance is proposed in this paper. As existing Luby Transform (LT)-based UEP codes with a property termed unequal recovery time (URT), which means that the data with different reliability requirements would be recovered with different overheads, which property would leading to a lower transmission efficiencies when all the portions of data have to be recovered. To overcome this drawback of existing UEP codes, the proposed UEP codes are carefully designed to provide equal water-fall region performances of all the portions of data. By using the well-known asymptotically analysis tool named as And-Or Tree, the asymptotic error performances of the proposed codes are given, and compared with the conventional LT-based UEP codes. All the theoretical analysis results and numerical results all prove that compared with conventional LT-based UEP codes, the proposed codes can provide higher transmission efficiency in the image data transmission in satellite communication systems.

Fault-Tolerant Routing Mechanism in 3D Optical Network-on-Chip Based on Node Reuse

The three-dimensional Network-on-Chips (3D NoCs) has become a mature multi-core interconnection architecture in recent years. However, the traditional electrical lines have very limited bandwidth and high energy consumption, making the photonic interconnection promising for future 3D Optical NoCs (ONoCs). Since existing solutions cannot well guarantee the fault-tolerant ability of 3D ONoCs, in this paper, we propose a reliable optical router (OR) structure which sacrifices less redundancy to obtain more restore paths. Moreover, by using our fault-tolerant routing algorithm, the restore path can be found inside the disabled OR under the deadlock-free condition, i.e., fault-node reuse. Experimental results show that the proposed approach outperforms the previous related works by maximum 81.1 percent and 33.0 percent on average for throughput performance under different synthetic and real traffic patterns. It can improve the system average optical signal to noise ratio (OSNR) performance by maximum 26.92 percent and 12.57 percent on average, and it can improve the average energy consumption performance by 0.3 percent to 15.2 percent under different topology types/sizes, failure rates, OR structures, and payload packet sizes.

Unleashing the hidden powers of low-cost IoT boards: GPU-based edutainment case study

The Ubiquitous interconnected smart devices enabled by the recent evolution of low-cost, generic, small-size, powerful computing platforms devised the term Internet of Things (IoT), which cross-cuts many areas of our modern day living. IoT applications go way beyond simple sensing and actuation to sophisticated localized processing and decision-making. The recent advances in embedded systems produced a long list of IoT boards equipped with powerful central processing units (CPUs), and graphics processing units (GPUs). Unfortunately, even with the limited energy consumption and high processing power of such GPUs, CPUs are usually the only computational element utilized by the hosted applications, thus hindering the capabilities of the entire board. This is mainly due to the complicated nature of GPU-based programming. In this paper, we are presenting a case study showing the effect of offloading the computationally intensive part of a latency-sensitive educational game to a low-cost Raspberry Pi’s GPU, thus enabling the board to seamlessly host the entire game operations. Relying mainly on the boards CPU shows very long interaction latency i.e., 4.82 s. By efficiently leveraging the powerful coprocessor, VideoCore GPU, we are able to significantly improve the interaction latency to a fraction of a second, making the game conveniently playable.

Experimental and numerical thermal performance assessment of a multi-layer building envelope component made of biocomposite materials

Building envelope systems are rapidly evolving, driven by increasingly stringent requirements for limiting energy consumption. Current trends favour lightweight, prefabricated wall assemblies with high levels of insulation, which have been shown to be particularly sensitive to thermal bridging through anchoring and framing elements. This paper presents a self-supporting multi-layer wall component made from bio-based materials, where novel biocomposite profiles are used instead of conventional metallic frames. The thermal performance of the proposed solution is calculated from numerical modelling and characterised through in-situ measurement of a full-scale prototype. For the plane areas of the wall with continuous insulation, theoretical calculations are broadly in line with results from experimental monitoring (7–15% deviation). Additionally, an area along a framing profile was specifically monitored, and it was found that the numerical model overestimated thermal resistance with a deviation of 121%. The presence of air gaps between the rigid insulation and framing elements, linked to the fabrication process of the prototype, was identified as a plausible cause. A subsequent explanatory numerical assessment, considering the effect of such cavities in the numerical model, provided results that are consistent with measurements from the experiment and previous literature. The study aims at demonstrating the insulation levels achievable with the use of novel bio-based materials of low thermal conductivity, and more generally, contributing to a better understanding of the thermal performance of framed lightweight insulated assemblies in service conditions, by monitoring and modelling the impact of thermal bridges and workmanship at framing elements.

Performance Analysis of MANET Proactive and Reactive Routing Protocols Using Network Simulator 2

The development of Mobile ad hoc networks (MANET) has the nature and character of a fast, costeffective. The development of Mobile ad hoc networks (MANET) has the nature and character of a fast, cost-effective deployment and able to manage the topology independently. This has caused in recent years, MANET to be an interesting and popular thing to study. MANET can be applied even in difficult areas, forest fire detection, military operations and even health monitoring. Changes in the topology dynamically on MANET, limited energy consumption, and built without existing infrastructure are a problem in MANET. Problems especially dynamic topology changes make routing very important in MANET design. This article aims to analyze AODV, DSDV and DSR routing protocols based on quality of service (QoS). The test scenario is based on the number of nodes, packet size, area of simulation, simulation time, simulation speed, mobility model, and propagation model. The simulation that has been done produces 4 graphs, each of which explains the packet delivery ratio, throughput, network routing load, and delay. Simulation results are obtained using NS2 network simulators through *. Tcl files and generate *. Tr (trace) and *.nam (animator) files. Simulation results show that the DSR routing protocol has better performance than AODV and DSDV in terms of pdr, throughput, network routing load, and delay. The average value of the DSR routing protocol is 657,498 on throughput and 0.244 milliseconds on delay.

Design and Implementation of Bitrate Adaptation Schemes for Power Capping in Wi-Fi Video Streaming

In dynamically adaptive streaming over HTTP (DASH), which is the de facto standard for streaming, each video is divided into segments, and each segment is further transcoded into multiple bitrate versions. This allows a client device to select the most appropriate bitrate version that matches the network bandwidth to avoid jitters or stalls. However, Wi-Fi download of a high-bitrate version may consume significant energy, especially when network conditions are good. To address this, we propose a new streaming method that limits the energy consumed by mobile devices but maintains an acceptable video quality. First, we derive a power model to analyze how bitrate selection affects power consumption in smartphones. Based on this, we propose two algorithms that determine the bitrate of each segment with the aim of maximizing overall video quality while limiting energy consumption. We use dynamic programming and heuristics to address the tradeoff between algorithm complexity and video quality. The proposed scheme was implemented on an Android-based DASH streaming platform, and various issues were resolved to cope with varying network conditions. Experimental results demonstrated that our scheme effectively optimized the video quality while limiting the energy consumption. For example: 1) our scheme uses 4% and 10% less power than DASH while maintaining an excellent video quality, and 2) the average difference between estimated and actual power consumption is 0.8%, thus keeping a precise energy bound.

Fuzzy simplified swarm optimization for multisite computational offloading in mobile cloud computing

Mobile Cloud Computing (MCC)’s rapid technological advancements facilitate various computational-intensive applications on smart mobile devices. However, such applications are constrained by limited processing power, energy consumption, and storage capacity of smart mobile devices. To mitigate these issues, computational offloading is found to be the one of the promising techniques as it offloads the execution of computation-intensive applications to cloud resources. In addition, various kinds of cloud services and resourceful servers are available to offload computationally intensive tasks. However, their processing speeds, access delays, computation capability, residual memory and service charges are different which retards their usage, as it becomes time-consuming and ambiguous for making decisions. To address the aforementioned issues, this paper presents a Fuzzy Simplified Swarm Optimization based cloud Computational Offloading (FSSOCO) algorithm to achieve optimum multisite offloading. Fuzzy logic and simplified swarm optimization are employed for the identification of high powerful nodes and task decomposition respectively. The overall performance of FSSOCO is validated using the Specjvm benchmark suite and compared with the state-of-the-art offloading techniques in terms of the weighted total cost, energy consumption, and processing time.

Simulating the drying behavior of rammed earth columns

Rammed earth construction provides an efficient alternative construction material to limit energy consumption and CO2 emission. It possesses various characteristics of a sustainable material, but its mechanical capacity is sensitive to humidity variations. It is, therefore, important to better understand water transport within rammed earth when subjected to varying ambient conditions. In this context, the present work aims to analyze the hydraulic behavior of a reduced piece of rammed earth wall consisting of a column of size 14cm x 14cm x 30cm subjected to drying from the initial compaction water content in an indoor environment. The columns had transient non-uniform relative humidity, which was measured in-situ. Thermo-hydraulic coupled numerical modeling was developed using realistic atmospheric boundary conditions. The material and hydric parameters were chosen from an experimental study previously performed at the material scale. A parametric study was performed in order to evaluate the sensitivity of the modeling to both material parameters and boundary conditions. The results of the numerical simulations were highly sensitive to parameter values used for the water retention curve and the surface mass transfer coefficient, with a satisfactory matching of experimental results only achieved after adjusting initial estimates of relevant parameter values.

Differential proteomic analyses of green microalga Ettlia sp. at various dehydration levels

Water deprivation could be a lethal stress for aquatic and aero-terrestrial organisms. Ettlia sp. is a unicellular photosynthetic freshwater microalga. In the present study, proteomic alterations and physiological characteristics of Ettlia sp. were analyzed to comprehend the molecular changes in dehydrated conditions. Varying levels of dehydration were achieved by incubating drained Ettlia sp. in different relative humidity environments for 24 hours. Using a comparative proteomic analysis, 52 differentially expressed protein spots were identified that could be divided into eight functional groups. The PCA analysis of normalized protein expression values demonstrated a clear segregation of protein expression profiles among different dehydration levels. Identified proteins could be grouped into four clusters based on their expression profiles. Proteins relating to photosynthesis comprised the largest group with 25% of the identified proteins that were decreased in dehydrated samples and belonged to cluster I. The photosynthetic activities were measured with rehydrated Ettlia sp. These results revealed that photosynthesis remained inhibited over extended time in response to dehydration. The expressions of reactive oxygen species (ROS) scavenger proteins increased in strong dehydration and were assigned to cluster III. Carbon metabolism proteins were suppressed, which might limit energy consumption, whereas glycolysis was activated at mild dehydration. The accumulation of desiccation-associated late embryogenesis proteins might inhibit the aggregation of housekeeping proteins. DNA protective proteins were expressed higher in the dehydrated state, which might reduce DNA damage, and membrane-stabilizing proteins increased in abundance in desiccation. These findings provide an understanding of Ettlia's adaptation and survival capabilities in a dehydrated state.

Energy Efficient Cognitive Radio Sensor Networks with Team-Based Hybrid Sensing

The massive growth in modern wireless technologies and devices has resulted in increase in spectrum demands and energy consumption of wireless sensor network (WSN). To overcome the spectral scarcity and to meet the energy requirements, a cognitive radio enabled WSN with an energy efficient medium access control protocol is required. However, existing approaches utilize either reactive sense and avoid approach or proactive spectrum access to reconfigure spectrum usage based on observations. In this paper, a team-based hybrid sensing method is proposed for cognitive radio sensor networks (CRSNs), which combines both reactive sensing and proactive sensing in a team based approach. Here, the sensor nodes are grouped into teams based on the detection probability of each primary user (PU) channels and each team senses a PU channel. To avoid sensing overheads and to limit energy consumption, a node with best detection probability $$(P_d)$$ called sensing representative node (SRN) is involved in reactive sensing. Dynamic channel allocation to the secondary users (SUs) with significantly increased throughput and reduced energy consumption are achieved by using proactive sensing. Proactive sensing predicts the primary user (PU) occupancy using SRNs and allows the SU transmission without any hindrance. Both simulation and software defined radio based hardware results show that, the proposed Hybrid Sensing improves the energy efficiency of CRSNs by $$11\%$$ over the existing sensing methods without degrading its sensing accuracy.

An Energy-efficient Distributed TDMA Scheduling Algorithm for ZigBee-like Cluster-tree WSNs

The design of Medium Access Control (MAC) protocol for Wireless Sensor Networks (WSNs) with both limited energy consumption and data delivery time is crucial for industrial and control applications. Since Time Division Multiple Access (TDMA) MAC eliminates the collision occurrence and seeks the minimization of the number of time-slots assigned to each node, the energy consumption of the nodes is reduced. Furthermore, with the proper allocation of the time-slots to the nodes, the transmission delay can be significantly reduced. In this article, we propose TDMA scheduling algorithm for Cluster-tree topology WSNs that meets the timeliness and the energy demands. The algorithm adopts an elegant approach that expresses the timing constraints of the data transmissions as an integer multiple of the length of the schedule period. Moreover, since the distributed algorithm is well-suited to the scarce resources of the WSNs, we focus on the distributed methods that allow each cluster to come up with its allocated time-slots. The algorithm is based on graph theory, such as distributed shortest path, distributed topological ordering, and distributed graph coloring algorithms. The efficiency of the algorithm, regarding the elapsed time to construct the schedule and the energy consumption, is evaluated over benchmark instances up to several thousands of nodes.

DECOMPOSITION OF ENERGY CONSUMPTION AND DECOUPLING ANALYSIS IN THE INDONESIAN INDUSTRY: AN ANALYSIS OF GREEN INDUSTRY

This study aims to identify ways that efficiently reduce the energy consumption of the industrial sector. We use the Logarithmic Mean Divisia index (LMDI) method to measure the impact of the various driving forces of energy consumption during the period 2010-2014. We then apply the index decoupling to analyze the correlation between energy consumption and industrial growth. The findings indicate that industrial growth is a major driver of energy consumption, while reductions in energy intensity and industrial structure play an important role in limiting energy consumption. In addition, energy consumption and energy intensity follow different patterns in each sub-sector; we therefore conclude that the application of different sub-sector policies is preferred over global policies. Globally, decoupling has not been identified during the period 2010-2014, however, decoupling occurs for more detailed year periods.Keywords: Energy consumption; LMDI; Decoupling.JEL Classifications: L52, L60, O25, Q43.DOI: https://doi.org/10.32479/ijeep.8027

Primary air treatment vs energy saving: comparison between different design solutions

In civil application the most diffuse type of HVAC is the mixed one made by fancoils and primary air system. Usually the primary air has not only the aim of replace the exhaust air in the rooms. During the cooling season air plants have the task of dehumidification of the indoor air which is humidified by the indoor humidity sources, like the human skin transpiration and breathing of the people. On the other hand, during the heating period the fresh air must be humidified to compensate the low humidity ratio of the external air. With the aim of energy saving related to the ventilation in buildings, from the beginning 2018 the new European Regulation EU 1253/2014 has been introduced some limits in terms of energy efficiencies. The present work investigates different layouts of plants for the primary air treatment in HVAC systems. Several types of heat recovery units have been considered in the study in order to find which is the best solution for the optimization of the air treatment. Several case studies have been considered in the energy analysis and the results obtained through numerical simulations have highlighted the critical nature of the interventions aimed at limiting energy consumption in primary air treatment systems.

The TRAPP complex mediates secretion arrest induced by stress granule assembly.

The TRAnsport Protein Particle (TRAPP) complex controls multiple membrane trafficking steps and is strategically positioned to mediate cell adaptation to diverse environmental conditions, including acute stress. We have identified the TRAPP complex as a component of a branch of the integrated stress response that impinges on the early secretory pathway. The TRAPP complex associates with and drives the recruitment of the COPII coat to stress granules (SGs) leading to vesiculation of the Golgi complex and arrest of ER export. The relocation of the TRAPP complex and COPII to SGs only occurs in cycling cells and is CDK1/2-dependent, being driven by the interaction of TRAPP with hnRNPK, a CDK substrate that associates with SGs when phosphorylated. In addition, CDK1/2 inhibition impairs TRAPP complex/COPII relocation to SGs while stabilizing them at ER exit sites. Importantly, the TRAPP complex controls the maturation of SGs. SGs that assemble in TRAPP-depleted cells are smaller and are no longer able to recruit RACK1 and Raptor, two TRAPP-interactive signaling proteins, sensitizing cells to stress-induced apoptosis.

GIS-based approach to identify climatic zoning: A hierarchical clustering on principal component analysis

In tropical environments, the design of bioclimatic houses adapted to their environment represents a crucial issue when considering thermal comfort and limiting energy consumption. A preliminary aspect of such design endeavors is the acquisition of accurate knowledge regarding the climatic conditions in each region of the studied territory. The objective of this paper is to propose a climatic zoning for Madagascar from a database of 47 meteorological stations by performing hierarchical clustering on principal components (HCPC). The results are then combined with spatial interpolation using geographic information system (GIS) tools, enabling us to define three climate zones corresponding to dry, humid and highland areas. These results make it possible to define standard meteorological files to evaluate the thermal performance of traditional Malagasy houses. Regardless of the type of house and the areas considered, the percentage of thermal comfort according to the Givoni bioclimatic chart varies from average values of 20% without ventilation to 70% with an air velocity of 1 m/s. In summary, Madagascar's traditional habitat typologies have adapted over time to the constraints of their environment.

Performance optimization of LoRa nodes for the future smart city/industry

The application of long-range communication technologies such as LoRa to certain environments like smart cities/industries is a natural step forward towards the future IoT. However, the strict limitations imposed in some countries on the duty cycle of ISM bands can jeopardize this technological progress. To overcome this and, at the same time, improve IoT nodes’ transmission and power efficiency, a novel mathematical model has been derived. Its numerical analysis leads to a closed-form formula that characterizes node performance in terms of its transmission policy. The maximization of this formula—required to increase node performance—is then posed as an optimization problem whose solution yields smart transmission policies that maximize throughput while limiting energy consumption. The results achieved under this approach are compared to those obtained using the ADR algorithm (the most extended mechanism for choosing transmission parameters in LoRaWAN networks) and to random/conservative policies to further highlight the benefits of the proposal. Results reveal that the proposed method outperforms ADR by 33.20%, the conservative policy by 91.81%, and the random policy by 238.8%.