Theoretical and Experimental Studies of an Elastic Plate as a Means of Identification of the Energy-efficient Fracturing of the Ore

2018 ◽  
Vol 4 (3) ◽  
pp. 12-26
Author(s):  
V. A. Kondratets ◽  
◽  
A. N. Matsui ◽  
Keyword(s):  
Elastic Plate ◽  
Energy Efficient ◽  
Experimental Studies

scholarly journals Opportunistic Large Array Propagation Models: A Comprehensive Survey

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 4206
Author(s):  
Farhan Nawaz ◽  
Hemant Kumar ◽  
Syed Ali Hassan ◽  
Haejoon Jung
Keyword(s):  
Energy Efficient ◽  
Large Scale ◽  
Performance Metrics ◽  
Experimental Studies ◽  
Cooperative Transmission ◽  
Analytical Models ◽  
Future Research ◽  
Large Array ◽  
Propagation Models ◽  
Comprehensive Survey

Enabled by the fifth-generation (5G) and beyond 5G communications, large-scale deployments of Internet-of-Things (IoT) networks are expected in various application fields to handle massive machine-type communication (mMTC) services. Device-to-device (D2D) communications can be an effective solution in massive IoT networks to overcome the inherent hardware limitations of small devices. In such D2D scenarios, given that a receiver can benefit from the signal-to-noise-ratio (SNR) advantage through diversity and array gains, cooperative transmission (CT) can be employed, so that multiple IoT nodes can create a virtual antenna array. In particular, Opportunistic Large Array (OLA), which is one type of CT technique, is known to provide fast, energy-efficient, and reliable broadcasting and unicasting without prior coordination, which can be exploited in future mMTC applications. However, OLA-based protocol design and operation are subject to network models to characterize the propagation behavior and evaluate the performance. Further, it has been shown through some experimental studies that the most widely-used model in prior studies on OLA is not accurate for networks with networks with low node density. Therefore, stochastic models using quasi-stationary Markov chain are introduced, which are more complex but more exact to estimate the key performance metrics of the OLA transmissions in practice. Considering the fact that such propagation models should be selected carefully depending on system parameters such as network topology and channel environments, we provide a comprehensive survey on the analytical models and framework of the OLA propagation in the literature, which is not available in the existing survey papers on OLA protocols. In addition, we introduce energy-efficient OLA techniques, which are of paramount importance in energy-limited IoT networks. Furthermore, we discuss future research directions to combine OLA with emerging technologies.

scholarly journals Investigation of the proposed solar-driven moisture phenomenon in asphalt shingle roofs

2016 ◽  
Vol 40 (4) ◽  
pp. 311-323
Author(s):  
Philip Boudreaux ◽  
Simon Pallin ◽  
Roderick Jackson
Keyword(s):  
Energy Efficient ◽  
National Laboratory ◽  
Experimental Studies ◽  
Absolute Humidity ◽  
Thermal Control ◽  
Oak Ridge ◽  
Significant Difference ◽  
Oak Ridge National Laboratory ◽  
Before And After ◽  
Roof Sheathing

Unvented attics are an energy-efficiency measure to reduce the thermal load of the conditioned space and decrease the space conditioning energy consumption by about 10%. This retrofit is usually done by spraying polyurethane foam underneath the roof sheathing, and on the gables and soffits of an attic to provide an air barrier and a thermal control layer. Unvented attics perform well from this perspective, but from a moisture perspective sometimes homes with unvented attics have high interior humidity or moisture damage to the roof. As homes become more air tight and energy efficient, a better understanding of the hygrothermal dynamics of homes with energy-efficient envelopes becomes more important. One proposed reason for high unvented attic humidity has been that moisture can come through the asphalt shingle roof system and increase the moisture content of the roof sheathing and attic air. This has been called “solar-driven moisture.” Oak Ridge National Laboratory investigated this proposed phenomenon by examining the physical properties of a roof and the physics required for the phenomenon. Results showed that there are not favorable conditions for solar-driven moisture to occur. Oak Ridge National Laboratory also conducted an experimental study in a home with an unvented attic and compared the humidity below the roof sheathing before and after a vapor impermeable underlayment was installed. There was no statistically significant difference in absolute humidity before and after the impermeable underlayment was installed. The outcomes of the theoretical and experimental studies suggest that solar-driven moisture does not occur in any significant amount.

scholarly journals Light concrete based on foam polyamidbe-tonic composition

2019 ◽  
Vol 7 (1) ◽  
pp. 70-75
Author(s):  
Левон Маилян ◽  
Levon Mailyan ◽  
Татьяна Голова ◽  
Tat'yana Golova
Keyword(s):  
Reinforced Concrete ◽  
Energy Efficient ◽  
Concrete Strength ◽  
Experimental Studies ◽  
Fiber Reinforced Concrete ◽  
Strength Characteristics ◽  
Building Structures ◽  
Optimal Composition ◽  
Foam Concrete ◽  
Layer Structures

One of the most important tasks of construction is the use of energy-efficient sin-gle-layer structures based on foam concrete and an increase in their bearing ca-pacity due to the use of fiber reinforcement, which will significantly improve the performance properties of fiber-reinforced concrete. Strength characteristics of fibro-foam concrete reinforced with polyamide granules with various types of filler and recommendations for its use in building structures were obtained. These experimental studies allow us to recommend the optimal composition of polyam-ide concrete compositions.

Sensorless and energy-efficient PMSM drive for fan application

2013 ◽  
Vol 62 (2) ◽  
pp. 217-225 ◽  
Author(s):  
Stefan Brock ◽  
Tomasz Pajchrowski
Keyword(s):  
Energy Efficient ◽  
Laboratory Tests ◽  
Permanent Magnets ◽  
Frequency Control ◽  
Experimental Studies ◽  
The Other ◽  
Stator Current ◽  
Current Vector ◽  
New Criterion ◽  
One Machine

Abstract The paper presents the problem of sensorless control of a permanent magnets synchronous motor (PMSM) without a damping cage for fan applications. Frequency control was used according to the principle of v/f = const. In order to reduce the power consumption of the drive system, the optimal voltage to the motor frequency characteristics was tested in the laboratory. The experimental studies was performed on a laboratory set of a drive consisting of two coupled PMSM machines, where one machine was supplied by a transistor inverter and the other was a passive load. A new criterion based on minimizing the module of stator current vector was proposed and an optimization algorithm in steady states was tested. The results of laboratory tests confirmed the validity of the applied solution for the fan drive.

Some Aspects of Improving the Efficiency of Air Treatment in the Contact Units of HVAC Systems

2017 ◽  
Author(s):  
Alexander Gvozdkov ◽  
Olga Suslova
Keyword(s):  
Energy Efficient ◽  
Experimental Studies ◽  
Water System ◽  
Hvac Systems ◽  
Moisture Exchange ◽  
Air Treatment ◽  
Working Space ◽  
Transition Area ◽  
Criterial Equations ◽  
Heat And Moisture

One of the main issues of improving the efficiency of air treatment in ventilation and air conditioning systems (HVAC systems) is development of methodology for the realization of energy-efficient air treatment processes in the contacting units. This paper investigates the thermodynamic models of “air-water” system, considering some features of the transition area at the interface, including surface phases and boundary layers of air and water. It has a great impact on the efficiency of processes of heat and moisture exchange in the contact units HVAC systems. The paper presents the results of experimental studies to determine the air-water interfaces temperature when achieving a state of thermodynamic balance condition in contacting media (air and water) in the working space of contact units. It was found that the surface temperature is determined by state of the surface phase and depends on the direction process of heat and moisture exchange (condensation or evaporation). The temperature factor k = Tdry/Ts as a criterion for determining the effect of the state transition area on the processes of heat and moisture exchange, was used. Processing of results from experimental researches in the processes of heat and mass transfer is presented in the form of criterial equations for Nu, Nu. Results of the performed research are the basis for the formulation of theoretical ideas about the energy efficient processes and the development of a new method for calculation of the contact units HVAC systems.

Municipal Heat Energy of Ukraine - Adaptation to Global Warming

2021 ◽  
Vol 23 ◽  
pp. 552-568
Author(s):  
Borys Basok
Keyword(s):  
Climate Change ◽  
Energy Efficient ◽  
Energy Supply ◽  
Renewable Energy Sources ◽  
Experimental Studies ◽  
Cost Effective ◽  
Theory And Practice ◽  
Engineering Systems ◽  
Adaptation To Climate Change ◽  
Basic And Applied Research

Rising global temperatures have exacerbated the problems of adaptation to climate change in various sectors of the economy, including municipal energy. Therefore, the task is to develop measures and mechanisms, the implementation of which will guarantee cost-effective comfortable and reliable heat and cold supply of buildings and structures in climate change. Experimental studies of heat transfer and monitoring of thermal regimes in enclosing structures and building elements were conducted with the development of innovative engineering systems for energy supply of a passive house of the "zero-energy" type. Experimental developments of innovative energy-efficient greenhouse gas-reducing technologies and equipment for energy supply systems of buildings have been performed and their architectural and construction solutions for adaptation to climate change have been optimized. In order to expand and deepen the theory and practice of improving the energy efficiency of buildings in the near future, the scientific priority and subject of basic and applied research have been identified. Developed adaptive to climate change innovative, energy efficient technologies and equipment of engineering systems of energy supply of buildings with the use of renewable energy sources can be used in the practice of energy supply of housing and communal services.

Assessment of efficiency of energy optimal driving mode for system of «pilot-free» movement of electric multiple units on the Moscow Central Ring

2020 ◽  
pp. 89-93
Author(s):  
Vasiliy Titovich Cheremisin ◽  
◽  
Mikhail Mikhaylovich Nikiforov ◽  
Alexander Sergeevich Vilgelm ◽  
Sergey Yuryevich Ushakov ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Power Consumption ◽  
Energy Efficient ◽  
Experimental Studies ◽  
Central Ring ◽  
Driving Mode ◽  
Optimal Driving ◽  
The Given ◽  
Smooth Acceleration ◽  
Multiple Units

According to results of experimental studies within the framework of the Moscow Central Ring the authors revealed the best trips of drivers in terms of energy efficiency of train traction. The analysis of these trips allowed determining riding techniques that provide energy saving: smooth acceleration and braking at unconditional performance of the given train schedule. On the basis of the developed simulation model of the Moscow Central Ring it is established that the use of energy efficient techniques of riding with the on time train performance can reduce the power consumption on train traction by 13.3 %.

scholarly journals Piezoelectric response of aligned carbon nanotubes depending on sublayer material

2021 ◽  
Vol 2086 (1) ◽  
pp. 012056
Author(s):  
M V Il’ina ◽  
O I Il’in ◽  
O I Osotova ◽  
N N Rudyk ◽  
O A Ageev
Keyword(s):  
Carbon Nanotubes ◽  
Energy Efficient ◽  
Experimental Studies ◽  
Geometric Parameters ◽  
Piezoelectric Response ◽  
Pressing Force ◽  
Mechanical Deformations ◽  
Aligned Carbon Nanotubes ◽  
Cnt Arrays

Abstract The results of experimental studies of the effect of the sublayer material on the piezoelectric response and sensitivity to mechanical deformations of aligned carbon nanotubes (CNTs) are presented. It is shown that the highest piezoelectric response (136 nA at a pressing force of 4 μN) and best sensitivity are demonstrated by CNTs grown on a Mo sublayer. This dependence is probably due to the geometric parameters of CNTs and the structure of the CNT array as a whole. The results obtained can be used to develop energy-efficient nanogenerators based on CNT arrays.

scholarly journals Fast File Transfers from IoT Devices by Using Multiple Interfaces

Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 36
Author(s):  
Leonardo Mostarda ◽  
Alfredo Navarra ◽  
Francesco Nobili
Keyword(s):  
Energy Efficient ◽  
Data Transfer ◽  
Experimental Studies ◽  
Efficient Solutions ◽  
The Internet ◽  
Basic Operation ◽  
File Transfer ◽  
Sensors And Actuators ◽  
File Transfers ◽  
5 Ghz

The Internet-of-Things (IoT) is a modern technological revolution that enables communication amongst a plethora of different devices. To date, about 30 billion devices have been connected to the internet and more than 75 billion devices are probably to be connected worldwide by 2025. These can range from small sensors and actuators to larger devices such as smartphones, drones or even buildings and interconnected cars. Devices are often mobile and battery powered thus their communication requires fast and energy efficient solutions. To this end, this paper studies the use of multi-interface communication for fast and energy efficient communication. In particular, we consider the basic operation of data transfer between smartphones in the form of files. This task can be performed for backup purposes, and hence it represents a useful and frequent operation that users perform. Our aim is to provide a new and easy means that optimises file transfers with respect to time and energy consumption. In particular, as smartphones are endowed with various connecting interfaces like Bluetooth, WiFi and 4G, we conduct experimental studies by varying different parameters in order to understand the best setting, including which interface is more appropriate to accomplish file transfer. To this respect, we also implemented an innovative and light app that allows the use of two or more interfaces concurrently. The experimental results show how the coupling of some interfaces might be effective in terms of time, while consuming a negligible amount of energy. Actually, such results become more and more interesting as the size of the file to be transferred grows. The best combination experienced is by making use of WiFi at 5 GHz concurrently with 4G, whereas WiFi at 2.4 GHz caused interference complications.

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