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Journal articles on the topic 'Smart radiator valves'
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1
Seri, Federico, Marco Arnesano, Marcus Martin Keane, and Gian Marco Revel. "Temperature Sensing Optimization for Home Thermostat Retrofit." Sensors 21, no. 11 (May 26, 2021): 3685. http://dx.doi.org/10.3390/s21113685.
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Most existing residential buildings adopt one single-zone thermostat to control the heating of rooms with different thermal conditions. This solution often provides poor thermal comfort and inefficient use of energy. The current market proposes smart thermostats and thermostatic radiator valves (TRVs) as cheap and relatively easy-to-install retrofit solutions. These systems provide increased freedom of installation, due to the use of wireless communication; however, the uncertainty of the measured air temperature, considering the thermostat placement, could impact the final heating performance. This paper presents a sensing optimization approach for a home thermostat, in order to determine the optimal retrofit configuration to reduce the sensing uncertainty, thus achieving the required comfort level and minimizing the retrofit’s payback period. The methodology was applied to a real case study—a dwelling located in Italy. The measured data and a simulation model were used to create different retrofit scenarios. Among these, the optimal scenario was achieved through thermostat repositioning and a setpoint of 21 °C, without the use of TRVs. Such optimization provided an improvement of control performance due to sensor location, with consequent energy savings of 7% (compared to the baseline). The resulting payback period ranged from two and a half years to less than a year, depending on impact of the embedded smart thermostat algorithms.
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Kull, Tuule Mall, Karl-Rihard Penu, Martin Thalfeldt, and Jarek Kurnitski. "Energy saving potential with smart thermostats in low-energy homes in cold climate." E3S Web of Conferences 172 (2020): 09009. http://dx.doi.org/10.1051/e3sconf/202017209009.
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Smart home systems with smart thermostats have been used for years. Although initially mostly installed for improving comfort, their energy saving potential has become a renowned topic. The main potential lies in temperature reduction during the times people are not home, which can be detected by positioning their phones. Even if the locating is precise, the maximum time people are away from home is short in comparison to the buildings’ time constants. The gaps are shortened by the smart thermostats, which start to heat up hours before occupancy to ensure comfort temperatures at arrival, and low losses through high insulation and heat-recovery ventilation in new buildings, which slow down the cool-down process additional to the thermal mass. Therefore, it is not clear how high the actual savings can be for smart thermostats in new buildings. In this work, a smart radiator valve was installed for a radiator in a test building. Temperature setback measurements were used to calibrate a simulation model in IDA ICE. A simulation analysis was carried out for estimating the energy saving potential in a cold climate for different usage profiles.
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Senthilkumar, K. S., K. Pirapaharan, P. R. P. Hoole, and R. R. H. Hoole. "Single Perceptron Model for Smart Beam forming in Array Antennas." International Journal of Electrical and Computer Engineering (IJECE) 6, no. 5 (October 1, 2016): 2300. http://dx.doi.org/10.11591/ijece.v6i5.10719.
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<p>In this paper, a single neuron neural network beamformer is proposed. A perceptron model is designed to optimize the complex weights of a dipole array antenna to steer the beam to desired directions. The objective is to reduce the complexity by using a single neuron neural network and utilize it for adaptive beamforming in array antennas. The selection of nonlinear activation function plays the pivotal role in optimization depends on whether the weights are real or complex. We have appropriately proposed two types of activation functions for respective real and complex weight values. The optimized radiation patterns obtained from the single neuron neural network are compared with the respective optimized radiation patterns from the traditional Least Mean Square (LMS) method. Matlab is used to optimize the weights in neural network and LMS method as well as display the radiation patterns.</p>
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Senthilkumar, K. S., K. Pirapaharan, P. R. P. Hoole, and R. R. H. Hoole. "Single Perceptron Model for Smart Beam forming in Array Antennas." International Journal of Electrical and Computer Engineering (IJECE) 6, no. 5 (October 1, 2016): 2300. http://dx.doi.org/10.11591/ijece.v6i5.pp2300-2309.
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<p>In this paper, a single neuron neural network beamformer is proposed. A perceptron model is designed to optimize the complex weights of a dipole array antenna to steer the beam to desired directions. The objective is to reduce the complexity by using a single neuron neural network and utilize it for adaptive beamforming in array antennas. The selection of nonlinear activation function plays the pivotal role in optimization depends on whether the weights are real or complex. We have appropriately proposed two types of activation functions for respective real and complex weight values. The optimized radiation patterns obtained from the single neuron neural network are compared with the respective optimized radiation patterns from the traditional Least Mean Square (LMS) method. Matlab is used to optimize the weights in neural network and LMS method as well as display the radiation patterns.</p>
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Krisna, Trismono C., Manfred Wendisch, André Ehrlich, Evelyn Jäkel, Frank Werner, Ralf Weigel, Stephan Borrmann, et al. "Comparing airborne and satellite retrievals of cloud optical thickness and particle effective radius using a spectral radiance ratio technique: two case studies for cirrus and deep convective clouds." Atmospheric Chemistry and Physics 18, no. 7 (April 3, 2018): 4439–62. http://dx.doi.org/10.5194/acp-18-4439-2018.
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Abstract. Solar radiation reflected by cirrus and deep convective clouds (DCCs) was measured by the Spectral Modular Airborne Radiation Measurement System (SMART) installed on the German High Altitude and Long Range Research Aircraft (HALO) during the Mid-Latitude Cirrus (ML-CIRRUS) and the Aerosol, Cloud, Precipitation, and Radiation Interaction and Dynamic of Convective Clouds System – Cloud Processes of the Main Precipitation Systems in Brazil: A Contribution to Cloud Resolving Modelling and to the Global Precipitation Measurement (ACRIDICON-CHUVA) campaigns. On particular flights, HALO performed measurements closely collocated with overpasses of the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Aqua satellite. A cirrus cloud located above liquid water clouds and a DCC topped by an anvil cirrus are analyzed in this paper. Based on the nadir spectral upward radiance measured above the two clouds, the optical thickness τ and particle effective radius reff of the cirrus and DCC are retrieved using a radiance ratio technique, which considers the cloud thermodynamic phase, the vertical profile of cloud microphysical properties, the presence of multilayer clouds, and the heterogeneity of the surface albedo. For the cirrus case, the comparison of τ and reff retrieved on the basis of SMART and MODIS measurements yields a normalized mean absolute deviation of up to 1.2 % for τ and 2.1 % for reff. For the DCC case, deviations of up to 3.6 % for τ and 6.2 % for reff are obtained. The larger deviations in the DCC case are mainly attributed to the fast cloud evolution and three-dimensional (3-D) radiative effects. Measurements of spectral upward radiance at near-infrared wavelengths are employed to investigate the vertical profile of reff in the cirrus. The retrieved values of reff are compared with corresponding in situ measurements using a vertical weighting method. Compared to the MODIS observations, measurements of SMART provide more information on the vertical distribution of particle sizes, which allow reconstructing the profile of reff close to the cloud top. The comparison between retrieved and in situ reff yields a normalized mean absolute deviation, which ranges between 1.5 and 10.3 %, and a robust correlation coefficient of 0.82.
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Khurshid, Adnan, Jian Dong, and Ronghua Shi. "A Metamaterial-Based Compact Planar Monopole Antenna for Wi-Fi and UWB Applications." Sensors 19, no. 24 (December 9, 2019): 5426. http://dx.doi.org/10.3390/s19245426.
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Ultrawideband (UWB) antennas are widely used as core devices in high-speed wireless communication. A novel compact UWB monopole antenna with an additional narrow band for Wi-Fi applications comprising a metamaterial (MTM) is proposed in this paper. The antenna has a compact size of 27 × 33 mm2 and consists of a V-shaped slot with two rectangular slots in the radiation patch. The inductance and capacitance develop due to the V-shaped slot in the radiation patch. The proposed antenna has −10 dB bandwidths of 3.2 GHz to 14 GHz for UWB and 2.38 GHz to 2.57 GHz for narrowband, corresponding to 144% and 7.66% fractional bandwidths, respectively. The measured gain and efficiency meet the desired values for UWB and Wi-Fi applications. To verify the performance of the antenna, the proposed antenna is fabricated and tested. The simulated and measured results agree well at UWB frequencies and Wi-Fi frequencies, and the antenna can be used as a smart device for portable IoT applications.
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Gotovkina, Elena, Vladimir Tyutikov, Nikolay Smirnov, Vladimir Lebedev, and Evgeniy Bushuev. "Influence of insolation and ambient temperature on operation of digital voltage transformers in Russia." MATEC Web of Conferences 178 (2018): 09005. http://dx.doi.org/10.1051/matecconf/201817809005.
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The present study is devoted to questions connected with influence of solar radiation and high values of ambient air temperatures on work of digital voltage transformers. The developed designs of digital voltage transformers are included in smart grid system of technical and commercial metering of electric energy consumption. The analysis of the unfavorable conditions for work of digital voltage transformers for the conditions of Russia in summer is carried out. The results of mathematical simulation for thermal state of transformers, obtained with the help of COMSOL Multiphysics program based on the finite element method, are presented. Experimental research regarding the thermal field of resistive voltage divider transformer was conducted on a verified mathematical model in order to determine the position of resistive elements where their self-heating is minimal.
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Di Salvo, Santina. "Kinetic Solutions for Responsive and Communicative Building Skin." Advanced Materials Research 1149 (August 2018): 86–97. http://dx.doi.org/10.4028/www.scientific.net/amr.1149.86.
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Theskinof buildings represents the first level of communication between construction, man and environment. In this relationship, the concept of communication acquires different values, because it can be applied both to the architectural field in relation to the shape, and to the perceptive and communicative sphere, aimed to transmission of messages or even to the interaction of the architectural envelope with the user and the environment. This brings us back to the energy and sustainability aspects, since the primary role as a separation and filter layer of the building façades is that of shielding. The solution with a kinetic façade constitutes not only a possibility of climatic mediation between outside and inside, guaranteeing ventilation and protection from solar radiation, but allows to redesign the aesthetic, communicative and perceptive appearance of a building. The contribution focuses on the communicative and perceptive potential of the façades and the ongoing experimentations of the new smart materials applied to these.
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Petropoulos, Ioannis, Konstantinos Voudouris, Raed A. Abd-Alhameed, Steve M. R. Jones, and Nikos Athanasopoulos. "A Novel Design of Microstrip Arrays for Relay-Based Wireless Network." International Journal of Antennas and Propagation 2011 (2011): 1–10. http://dx.doi.org/10.1155/2011/870183.
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A relay station (RS) is a smart transceiver used under a 4G wireless network in order to extend network's coverage and capacity. It uses an antenna system that includes an antenna for connecting the relay with the end users (access link) and the RS with the base station (backhaul link). In this paper, a 7.9 dBi access and 11.4 dBi backhaul antennas are presented for the frequency range of 3.3 to 3.8 GHz. The antennas are simulated and fabricated, and relevant measured results in terms of return loss and radiation pattern are presented and analyzed. Considering that the planes of those two antennas are positioned in an angle (omega), two antenna configuration geometries are tested in terms of coupling. The experimental results of for several values of the angle show that the interaction between the radiating elements is dependent on their relative position. Simulated and experimental results are in good agreement, showing coupling typically less than −40 dB. A comparison in terms of coupling between the proposed antennas and commercial ones proves that the suggested antennas provide 10 dB lower coupling.
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Roy, Nayan. "Population ecology and ETs based time series for climate smart pest management of Spilosoma obliqua Walker." ENTOMON 45, no. 1 (March 31, 2020): 15–30. http://dx.doi.org/10.33307/entomon.v45i1.500.
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The two-sex pooled life table of S. obliqua Walker (Lepidoptera: Arctiidae) was constructed along with their population density and yield loss estimation to determine their economic thresholds (ETs) based time series on two different crops such as sesame (S. indicum; cv. Rama) and green gram (V. radiata; cv. KB-54) in 2019. The population ecology and ETs of S. obliqua were significantly (P<0.05) affected by the host phytoconstituents in terms of host suitability or susceptibility (sesame>green gram). Average EIL and ET for S obliqua was 26.388±1.627 and 24.230±2.412 pests/30 plants, respectively for sesame that were insignificantly (F1,4=2.794-3.335; P≥0.142) differed from the green gram. For a single pest per m2 (30±2 plants/m2) the possible time that can be taken to reach EIL (Ti) and ET (Tt) were 38.246±1.157 and 37.246±1.157 days, respectively on sesame which were significantly (F1,4=24.111; P=0.008) lower than green gram. Even, ETs based time series was also calculated to find the specific time (Tt days) to reach ET for any number of pest(s) on the selected crops for time based management. The benefit cost ratio (BCR/ha) of sesame and green gram was 0.478 and 0.390, respectively with significant (P<0.05) deviation. The carbon sequestration efficiency (CSE) of sesame (301.860 kg/ha) was significantly (P<0.05) higher than green gram (172.260 kg/ha) due to more biomass production. These findings will obviously help farmers to choose sesame as a suitable trap crop for green gram on the basis of pest attraction or susceptibility, ETs based time series, BCR values (sesame>green gram) as well as CSE for climate smart pest management (CSPM) by applying appropriate control measures judiciously if required within the time limit to reach the ETs as in time series for sustainable climate smart agriculture (CSA) of such crops in near future.
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Fedosov, S. V., A. A. Lazarev, M. V. Toropova, and V. G. Malichenko. "EQUATIONS FOR THE OPERATING TEMPERATURE OF THERMOSENSITIVE ELEMENTS OF FIRE DETECTORS EMBEDDED IN A CONCRETE BLOCK." Russian Journal of Building Construction and Architecture, no. 4(48) (January 6, 2021): 31–38. http://dx.doi.org/10.36622/vstu.2020.48.4.004.
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Statement of the problem. Solving the problem of giving the properties of a building structure to detect fires outside buildings is one of the ways to prevent the transition of fire from one building to another. Embedding of fire automation equipment in construction products should be carried out after making the appropriate calculations. The absence of an expression for determining the temperature of the heat-sensitive element of a fire detector inside a concrete block requires detailed calculations. At the same time, it is necessary to study the influence of the distance to the object of a possible fire, the size of the heat-sensitive element, and the heat flow on the time of fire detection by a construction product included in the smart home system.Results. As part of the temperature measurement of heat-sensitive elements of fire detectors inside the concrete block, empirical data were obtained. This information allows us to describe the radiant heat exchange at an early stage of a fire. This is typical of open burning outdoors. Conclusions. Approximate equations are obtained for determining the temperature and response time of a fire detector inside a concrete block at the initial stage of a fire, depending on the distance to the fire object (radiation source), heat flow, and the size of the thermosensitive element. These values can be determined with sufficient accuracy.
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Fedosov, S. V., A. A. Lazarev, M. V. Toropova, and V. G. Malichenko. "EQUATIONS FOR THE OPERATING TEMPERATURE OF THERMOSENSITIVE ELEMENTS OF FIRE DETECTORS EMBEDDED IN A CONCRETE BLOCK." Russian Journal of Building Construction and Architecture, no. 4(48) (January 6, 2021): 31–38. http://dx.doi.org/10.36622/vstu.2020.48.4.004.
Full textAbstract:
Statement of the problem. Solving the problem of giving the properties of a building structure to detect fires outside buildings is one of the ways to prevent the transition of fire from one building to another. Embedding of fire automation equipment in construction products should be carried out after making the appropriate calculations. The absence of an expression for determining the temperature of the heat-sensitive element of a fire detector inside a concrete block requires detailed calculations. At the same time, it is necessary to study the influence of the distance to the object of a possible fire, the size of the heat-sensitive element, and the heat flow on the time of fire detection by a construction product included in the smart home system.Results. As part of the temperature measurement of heat-sensitive elements of fire detectors inside the concrete block, empirical data were obtained. This information allows us to describe the radiant heat exchange at an early stage of a fire. This is typical of open burning outdoors. Conclusions. Approximate equations are obtained for determining the temperature and response time of a fire detector inside a concrete block at the initial stage of a fire, depending on the distance to the fire object (radiation source), heat flow, and the size of the thermosensitive element. These values can be determined with sufficient accuracy.
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Buckus, Raimondas, Birute Strukcinskiene, Juozas Raistenskis, and Rimantas Stukas. "Modelling and assessment of the electric field strength caused by mobile phone to the human head." Vojnosanitetski pregled 73, no. 6 (2016): 538–43. http://dx.doi.org/10.2298/vsp141221044b.
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Background/Aim. Electromagnetic field exposure is the one of the most important physical agents that actively affects live organisms and environment. Active use of mobile phones influences the increase of electromagnetic field radiation. The aim of the study was to measure and assess the electric field strength caused by mobile phones to the human head. Methods. In this paper the software ?COMSOL Multiphysics? was used to establish the electric field strength created by mobile phones around the head. Results. The second generation (2G) Global System for Mobile (GSM) phones that operate in the frequency band of 900 MHz and reach the power of 2 W have a stronger electric field than (2G) GSM mobile phones that operate in the higher frequency band of 1,800 MHz and reach the power up to 1 W during conversation. The third generation of (3G) UMTS smart phones that effectively use high (2,100 MHz) radio frequency band emit the smallest electric field strength values during conversation. The highest electric field strength created by mobile phones is around the ear, i.e. the mobile phone location. The strength of mobile phone electric field on the phantom head decreases exponentially while moving sidewards from the center of the effect zone (the ear), and constitutes 1-12% of the artificial head?s surface. Conclusion. The highest electric field strength values of mobile phones are associated with their higher power, bigger specific energy absorption rate (SAR) and lower frequency of mobile phone. The stronger electric field emitted by the more powerful mobile phones takes a higher percentage of the head surface. The highest electric field strength created by mobile phones is distributed over the user ear.
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Erenoğlu, Çiçek, Arıkan, Erdinç, and Catalão. "A New Approach for Grid-Connected Hybrid Renewable Energy System Sizing Considering Harmonic Contents of Smart Home Appliances." Applied Sciences 9, no. 18 (September 19, 2019): 3941. http://dx.doi.org/10.3390/app9183941.
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Even renewable energy sources provide several advantages, especially from an environmental point of view, where the world has faced great challenges in the last few decades; several negative issues also exist regarding the integration of renewable resources-based power production units in electric power systems. One of the main problems related to pivotal renewable energy resources such as solar, wind, etc., is their stochastic and uncontrollable nature in terms of power production. Therefore, this stochasticity in the supply side of the power system may pose many challenges for system operators. This issue is also problematic for smaller applications where the stochastic production by a main resource, such as a roof-top photovoltaic system, and load demand may not match perfectly at each time instant and therefore should be compensated by additional resources such as battery-based energy storage systems. Herein, the economic considerations to ensure minimum costs for such a hybrid system design are vital so as to increase the penetration of such systems. Therefore, the optimal sizing and planning of hybrid systems have recently gained increasing importance to enhance power system operation in the context of the smart grid paradigm. From a different perspective, harmonics are one of the most important power quality problems in system operations caused by widespread integration of power electronic loads with non-linear characteristics that should be considered. Thus, a new approach for grid-connected hybrid renewable energy system sizing is provided. In order to determine optimal capacities for photovoltaic (PV) and energy storage system (ESS) units for covering residential consumer demand, a mixed integer linear programming (MILP)-based formulation is presented. The main objective is minimizing total costs of the system consisting of investment, capital and maintenance cost functions. A daily power curve is created accurately with real measurements of non-linear loads considering harmonic contents of smart home appliances in Yildiz Technical University, Istanbul, Turkey. In addition, real radiation and temperature values are used in PV production as well as dynamic pricing schemes for realistic evaluations. Moreover, optimal sizing results are compared for both the harmonic-based power curve and rated power curve in terms of satisfying objective function.
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Martins, Rui M. S., Norbert Schell, H. Reuther, Luís Pereira, Rui Jorge C. Silva, Karimbi Koosappa Mahesh, and Francisco Manuel Braz Fernandes. "Characterization of Ni-Ti (Shape Memory Alloy) Thin Film by In Situ XRD and Complementary Ex Situ Techniques." Materials Science Forum 587-588 (June 2008): 672–76. http://dx.doi.org/10.4028/www.scientific.net/msf.587-588.672.
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Ni-Ti SMA are smart materials undergoing first order martensitic transformations driven by temperature and/or stress. In the form of film they are very attractive candidates for microelectro- mechanical system (MEMS) applications. Future directions include the production of functionally graded films by changing deliberately the ratio Ti/Ni across their thickness. However, for the successful development of this type of films, it is important to characterize, model and control the variations in composition, crystalline structure and transformation temperatures. Our approach is in-situ XRD study of the actual growth of the films of varying composition along the thickness carried out using a deposition chamber installed at a synchrotron radiation beamline. These studies were complemented with ex-situ analysis techniques. The results achieved on a Ni-Ti film co-sputtered from Ni-Ti and Ti targets on a TiN buffer layer are presented in this paper. The deposition started by using optimised parameters for a near equiatomic composition. After 1 h (≈330 nm thick film), the Ti power was increased from 20 to 25 W, leading to the precipitation of Ti2Ni. The evolution of the lattice parameter values of the B2 phase, calculated from the corresponding XRD data, is clearly linked with the increase of the Ti power. The depth profile of the atomic concentrations determined by Auger Electron Spectroscopy (AES) is in agreement with the in situ XRD results. The temperature dependence of the electrical resistivity was used to monitor phase transformations, Scanning Electron Microscopy (SEM) has shown the presence of twinned martensite on the film’s surface at room temperature.
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Kaplani, Eleni, and Socrates Kaplanis. "Dynamic Electro-Thermal PV Temperature and Power Output Prediction Model for Any PV Geometries in Free-Standing and BIPV Systems Operating under Any Environmental Conditions." Energies 13, no. 18 (September 11, 2020): 4743. http://dx.doi.org/10.3390/en13184743.
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PV temperature significantly affects the module’s power output and final system yield, and its accurate prediction can serve the forecasting of PV power output, smart grid operations, online PV diagnostics and dynamic predictive management of Building Integrated Photovoltaic (BIPV) systems. This paper presents a dynamic PV temperature prediction model based on transient Energy Balance Equations, incorporating theoretical expressions for all heat transfer processes, natural convection, forced convection, conduction and radiation exchanges between both module sides and the environment. The algorithmic approach predicts PV temperature at the centre of the cell, the back and the front glass cover with fast convergence and serves the PV power output prediction. The simulation model is robust, predicting PV temperature with high accuracy at any environmental conditions, PV inclination, orientation, wind speed and direction, and mounting configurations, free-standing and BIPV. These, alongside its theoretical basis, ensure the model’s wide applicability and clear advantage over existing PV temperature prediction models. The model is validated for a wide range of environmental conditions, PV geometries and mounting configurations with experimental data from a sun-tracking, a fixed angle PV and a BIPV system. The deviation between predicted and measured power output for the fixed-angle and the sun-tracking PV systems was estimated at −1.4% and 1.9%, respectively. The median of the temperature difference between predicted and measured values was as low as 0.5 °C for the sun-tracking system, and for all cases, the predicted temperature profiles were closely matching the measured profiles. The PV temperature and power output predicted by this model are compared to the results produced by other well-known PV temperature models, illustrating its high predictive capacity, accuracy and robustness.
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Ehrlich, André, Eike Bierwirth, Larysa Istomina, and Manfred Wendisch. "Combined retrieval of Arctic liquid water cloud and surface snow properties using airborne spectral solar remote sensing." Atmospheric Measurement Techniques 10, no. 9 (September 4, 2017): 3215–30. http://dx.doi.org/10.5194/amt-10-3215-2017.
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Abstract. The passive solar remote sensing of cloud properties over highly reflecting ground is challenging, mostly due to the low contrast between the cloud reflectivity and that of the underlying surfaces (sea ice and snow). Uncertainties in the retrieved cloud optical thickness τ and cloud droplet effective radius reff, C may arise from uncertainties in the assumed spectral surface albedo, which is mainly determined by the generally unknown effective snow grain size reff, S. Therefore, in a first step the effects of the assumed snow grain size are systematically quantified for the conventional bispectral retrieval technique of τ and reff, C for liquid water clouds. In general, the impact of uncertainties of reff, S is largest for small snow grain sizes. While the uncertainties of retrieved τ are independent of the cloud optical thickness and solar zenith angle, the bias of retrieved reff, C increases for optically thin clouds and high Sun. The largest deviations between the retrieved and true original values are found with 83 % for τ and 62 % for reff, C. In the second part of the paper a retrieval method is presented that simultaneously derives all three parameters (τ, reff, C, reff, S) and therefore accounts for changes in the snow grain size. Ratios of spectral cloud reflectivity measurements at the three wavelengths λ1 = 1040 nm (sensitive to reff, S), λ2 = 1650 nm (sensitive to τ), and λ3 = 2100 nm (sensitive to reff, C) are combined in a trispectral retrieval algorithm. In a feasibility study, spectral cloud reflectivity measurements collected by the Spectral Modular Airborne Radiation measurement sysTem (SMART) during the research campaign Vertical Distribution of Ice in Arctic Mixed-Phase Clouds (VERDI, April/May 2012) were used to test the retrieval procedure. Two cases of observations above the Canadian Beaufort Sea, one with dense snow-covered sea ice and another with a distinct snow-covered sea ice edge are analysed. The retrieved values of τ, reff, C, and reff, S show a continuous transition of cloud properties across snow-covered sea ice and open water and are consistent with estimates based on satellite data. It is shown that the uncertainties of the trispectral retrieval increase for high values of τ, and low reff, S but nevertheless allow the effective snow grain size in cloud-covered areas to be estimated.
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Федосов, С. В., А. А. Лазарев, М. В. Торопова, and В. Г. Маличенко. "EQUATIONS FOR THE OPERATING TEMPERATURE OF THERMOSENSITIVE ELEMENTS OF FIRE DETECTORS EMBEDDED IN A CONCRETE BLOCK." НАУЧНЫЙ ЖУРНАЛ СТРОИТЕЛЬСТВА И АРХИТЕКТУРЫ, no. 4(60) (December 29, 2020): 35–42. http://dx.doi.org/10.36622/vstu.2020.60.4.003.
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Постановка задачи. Решение проблемы придания строительной конструкции свойств, позволяющих обнаруживать пожары вне зданий, является одним из направлений предупреждения перехода огня с одного здания на другое. Встраивание средств пожарной автоматики в строительные изделия должно осуществляться после проведения соответствующих расчетов. Отсутствие выражения, позволяющего определить температуру термочувствительного элемента пожарного извещателя, встроенного в бетонный блок, вынуждает проводить детальные расчеты. Вместе с тем, необходимо исследовать влияние расстояния до объекта возможного пожара, размера термочувствительного элемента, теплового потока на время обнаружения пожара строительным изделием, входящим в систему «умный дом». Результаты. В процессе измерения температуры термочувствительных элементов пожарных извещателей, встроенных в бетонные блоки, получены эмпирические данные, позволяющие описать на ранней стадии пожара лучистый теплообмен, характерный для открытого горения вне помещений. Выводы. Получены приближенные уравнения, которые позволяют с достаточной точностью определить температуру и время срабатывания пожарного извещателя, встроенного в бетонный блок, на начальной стадии пожара в зависимости от расстояния до объекта пожара (источника излучения), теплового потока, размера термочувствительного элемента. Statement of the problem. Solving the problem of giving the properties of a building structure to detect fires outside buildings is one of the ways to prevent the transition of fire from one building to another. Embedding of fire automation equipment in construction products should be carried out after making the appropriate calculations. The absence of an expression for determining the temperature of the heat-sensitive element of a fire detector inside a concrete block requires detailed calculations. At the same time, it is necessary to study the influence of the distance to the object of a possible fire, the size of the heat-sensitive element, and the heat flow on the time of fire detection by a construction product included in the smart home system. Results. As part of the temperature measurement of heat-sensitive elements of fire detectors inside the concrete block, empirical data were obtained. This information allows us to describe the radiant heat exchange at an early stage of a fire. This is typical of open burning outdoors. Conclusions. Approximate equations are obtained for determining the temperature and response time of a fire detector inside a concrete block at the initial stage of a fire, depending on the distance to the fire object (radiation source), heat flow, and the size of the thermosensitive element. These values can be determined with sufficient accuracy.
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Cámara, F., E. Sokolova, F. C. Hawthorne, and Y. Abdu. "From structure topology to chemical composition. IX. Titanium silicates: revision of the crystal chemistry of lomonosovite and murmanite, Group-IV minerals." Mineralogical Magazine 72, no. 6 (December 2008): 1207–28. http://dx.doi.org/10.1180/minmag.2008.072.6.1207.
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AbstractThe crystal structures of lomonosovite, ideally Na10Ti4(Si2O7)2(PO4)2 O4, a = 5.4170(7) Å, b = 7.1190(9) Å, c = 14.487(2) Å, a = 99.957(3)°, β = 96.711(3)°, γ = 90.360(3)°, V= 546.28(4) Å3, Dcalc. = 3.175 g cm“3, and murmanite, ideally Na4Ti4(Si2O7)2O4(H2O)4, a = 5.3875(6) Å, b = 7.0579(7) Å, c = 12.176(1) Å, a = 93.511(2)°, 0 = 107.943(4)°, y = 90.093(2)°, V = 439.55(2) Å3, Dcalc. = 2.956 g.cm∼3, from the Lovozero alkaline massif, Kola Peninsula, Russia, have been refined in the space group P1̄ (Z = 1) to R values of 2.64 and 4.47%, respectively, using 4572 and 2222 observed |F°≥ 4σF| reflections collected with a single-crystal Bruker AXS SMART APEX diffractometer with a CCD detector and Mo-Kα. radiation. Electron microprobe analysis gave empirical formulae for lomonosovite (Na9.50Mn0.16Ca0.11)Σ9.77(Ti4+2.83Nb0.51Mn0.272+Zr0.11Mg0.11Fe2+0.10Fe3+0.06Ta0.01)Σ4.00(Si2.02O7)2(P0.98O4)2(O3.50F0.50)Σ4, Z = 1, calculated on the basis of 22(O+F) a.p.f.u., with H2O determined from structure refinement and Fe3+/(Fe2++Fe3+) ratios obtained by Mössbauer spectroscopy. The crystal structures of lomonosovite and murmanite are a combination of a titanium silicate (TS) block and an intermediate (I) block. The TS block consists of HOH sheets (H-heteropolyhedral, O-octahedral), and is characterized by a planar cell based on translation vectors, t1 and t2, with t1\ ∼5.5 and t2 ∼7 Å and ttA t2 close to 90°. The TS block exhibits linkage and stereochemistry typical for Group IV (Ti = 4 a.p.f.u.) of the Ti disilicate minerals: two H sheets connect to the O sheet such that two (Si2O7) groups link to Ti polyhedra of the O sheet adjacent along tx. In murmanite and lomonosovite, the invariant part of the TS block is of composition Na4Ti4(Si2O7)2O4. There is no evidence of vacancy-dominant cation sites or (OH) groups in the O sheet of lomonosovite or murmanite. In lomonosovite, the I block is a framework of Na polyhedra and P tetrahedra which gives 2[Na3 (PO)4] p.f.u. In murmanite, there are four (H2O) groups in the intermediate space between TS blocks. In lomonosovite, TS and I blocks alternate along c. In murmanite, TS blocks are connected via hydrogen bonding. The H atoms were located and details of the hydrogen bonding are discussed.
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Bakhsh, Ahmed A. "Gamma-Ray Modified Polymer/Clay Composites: Synthesis, Characterization, and Formulation Optimization Using Multivariate Calculus and Graph Theory." Energies 14, no. 9 (May 10, 2021): 2724. http://dx.doi.org/10.3390/en14092724.
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To enhance the oxidation strength and crosslinking yield of ultrahigh molecular weight polyethylene (UHMWPE), its composites were prepared by mixing 1%, 2%, and 3% (by wt.) of magnesium silicate hydrous (sepiolite) during this study. These composites were irradiated with 25 kGy and 50 kGy of irradiation doses in the open air. Subsequent to irradiation, the composites were characterized for updates in structure, oxidation strength, and degree of crosslinking while estimating the values of oxidation index (OI), crosslink density (Gx), and percent crystallinity (Xc), respectively. The reaction of modified sepiolite (SP) on irradiating UHMWPE/SP composites was evident from the origination of peaks at Si-O, O-Si-O, Si-O-Si, and Mg-OH and stretching vibration at 974 cm−1, 1014 cm−1, and 1080 cm−1, respectively. In addition, the moderate negative correlation of OI (−0.46) and strong positive correlation of Gx (0.87) with the absorbed dose, made obvious from correlation analysis, confirmed the effectiveness of SP in enhancing the oxidation strength and crosslink density of UHMWPE. Furthermore, cluster analysis (CA) grouped the composites as low, moderate, and best based on dissimilarities, i.e., oxidation strength and crosslink density, which was further confirmed by principal component analysis (PCA). PCA also revealed that the OI, Gx, and absorbed dose were the active variables for this best group. After confirming the effectiveness of SP (as an active filler for enhancing the oxidation strength and crosslink density of UHMWPE) and recognizing the OI, Gx, and absorbed dose as active variables, the next step was to determine the necessary minimum amount of SP concentration and radiation dose required for the composite that outperforms all others. For this, a parametric graph theory and matrix approach was employed to rank the composites of the best group, revealing that the UHMWPE/SP composite with 1% (by wt.) of Si12O30Mg8(OH)4(H2O)4·8H2O and irradiated with 50 kGy of irradiation dose was the most suitable choice of all existing alternatives tested in this study. Although this is the first attempt, to the best of our knowledge, where a smart approach using multivariate calculus and decision-making tools was utilized for figuring the best UHMWPE composite formulation along with appropriate treatment dose, the results and methodology could be extended for any polymer of industrial scale, such as those used in medical implants, defense armor, bulletproof jackets, etc.
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Kusznier, Jacek. "Influence of spectral properties of light sources on perceived and recorded images." Photonics Letters of Poland 13, no. 2 (June 30, 2021): 40. http://dx.doi.org/10.4302/plp.v13i2.1105.
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The text presents differences between the mechanism of seeing and recording images and potential sources of errors in color reproduction in recorded images. The measurements show that despite the relatively high values of indices (Ra, Rf i Rg) not all tested lamps are suitable for use on a photo set, as indicated by the value of TLCI index. The lighting requirements on a film set prioritize the quality of color reproduction, even at the expense of reducing the Luminous efficacy of a source (LES ) value. Full Text: PDF ReferencesL.T. Sharpe, A. Jagla, W. Jägle, "A luminous efficiency function, V*(λ), for daylight adaptation", J. Vision 5(11), 948 (2012) DirectLink K. Mangold, J.A. Shaw, M. Vollmer, The physics of near-infrared photography, Eur. J. Phys. 34 (2013), pp. 51-71 CrossRef Simunovic M. P., On Seeing Yellow The Case for, and Against, Short-Wavelength Light-Absorbing Intraocular Lenses, Archives of Ophthalmology, vol. 130, no. 7, pp. 919-926, 2012 CrossRef M. Gilewski, The ecological hazard of artificial lighting in greenhouses, Phot. Lett. Pol., vol. 11 Issue: 3, pp. 87-89, 2019. CrossRef M. Gilewski, The role of light in the plants world, Phot. Lett. Pol., vol. 11, no. 4, pp. 115-117, 2019 CrossRef I. Fryc and E. Czech Spectral correction of the measurement CCD array, Optical Engineering 41(10), pp.2402-2406 (2002). CrossRef L. Bellia, U. Blaszczak, F. Fragliasso, L. Gryko, Matching CIE illuminants to measured spectral power distributions: A method to evaluate non-visual potential of daylight in two European cities, Solar Energy, Volume 208, 2020, Pages 830-858 CrossRef J. Kusznier and W. Wojtkowski, Impact of climatic conditions on PV panels operation in a photovoltaic power plant, IEEE, 2019 15th Selected Issues of Electrical Engineering and Electronics (WZEE), Zakopane, Poland, pp. 1-6, 2019 CrossRef J. Kusznier and W. Wojtkowski, Impact of climatic conditions and solar exposure on the aging of PV panels, IEEE, 2019 15th Selected Issues of Electrical Engineering and Electronics (WZEE), Zakopane, Poland, pp. 1-6, 2019 CrossRef J. Fan, Y. Li, I. Fryc, C. Qian, X. Fan and G. Zhang, Machine-Learning Assisted Prediction of Spectral Power Distribution for Full-Spectrum White Light-Emitting Diode, in IEEE Photonics Journal, vol. 12, no. 1, pp. 1-18, Feb. 2020, Art no. 8200218, CrossRef M. Gilewski, L. Gryko, A. Zajac, Digital controlling system to the set of high power LEDs, Proc. of SPIE, 8902, 89021D, 2013 CrossRef J. Kusznier, W. Wojtkowski, Spectral properties of smart LED lamps, Phot. Lett. Pol., vol. 12, no. 1, pp. 16-18, 2020. CrossRef J. Kusznier, Changes in the Spectral Power Distribution of Light Sources for Smart Lighting, IEEE, 14th WZEE, pp. 1-5, 2018 CrossRef H. F. Ivey, Color and Efficiency of Luminescent Light Sources, J. Opt. Soc. Am. 53, 1185-1198 (1963) CrossRef F. Zhang, H. Xu, Z. Wang, Optimizing spectral compositions of multichannel LED light sources by IES color fidelity index and luminous efficacy of radiation, Appl. Opt. 56, 1962-1971 (2017) CrossRef T. W. Murphy Jr., Maximum spectral luminous efficacy of white light, Journal of Applied Physics 111, 104909 (2012) CrossRef Po-Chieh Hung and Jeffrey Y. Tsao, Maximum White Luminous Efficacy of Radiation Versus Color Rendering Index and Color Temperature: Exact Results and a Useful Analytic Expression, J. Display Technol. 9, 405-412 (2013) CrossRef V. M. Lisitsyn, V. S. Lukash, S. A. Stepanov, and Ju Yangyang , White LEDs with limit luminous efficacy, AIP Conference Proc 1698, 060008 (2016) CrossRef J. Kowalska, I. Fryc, Colour rendition quality of typical fluorescent lamps determined by CIE Colour Fidelity Index and Colour Rendering Index, Przeglad Elektrotechniczny R. 95(7), pp. 94-97, 2019 CrossRef I. Fryc, J. Fryc, A. Wasowski, "Rozważania o jakości oddawania barw źródeł światła, wyrażanej wskaźnikiem Ra (CRI), uwzględniające fizjologię widzenia oraz zagadnienia techniczno-prawne", Przeglad Elektrotechniczny R. 92(2), 218 (2016) CrossRef TECH 3353, Development of a "standard" television camera model implemented in the TLCI-2012, Source: FTV-LED, EBU, Geneva November 2012 DirectLink TECH 3354, Comparison of CIE colour metrics for use in the television lighting consistency index (TLCI-2012), Source: FTV-LED, EBU, Geneva November 2012 DirectLink TECH 3355, Method for the assessment of the colorimetric properties of luminaires the television lighting consistency index (TLCI-2012) and the television luminaire matching factor (TLMF-2013), Source: FTV-LED Geneva March 2017 DirectLink J. Kusznier, Mixing colours inside the optical fibre elements, Przeglad Elektrotechniczny, R 84(8), pp 182-185, 2008 DirectLink
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Mitchell, T., M. Salah, J. Wagner, and D. Dawson. "Automotive Thermostat Valve Configurations: Enhanced Warm-Up Performance." Journal of Dynamic Systems, Measurement, and Control 131, no. 4 (April 29, 2009). http://dx.doi.org/10.1115/1.3117183.
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The automotive cooling system has unrealized potential to improve internal combustion engine performance through enhanced coolant temperature control and reduced parasitic losses. Advanced automotive thermal management systems use controllable actuators (e.g., smart thermostat valve, variable speed water pump, and electric radiator fan) that must work in harmony to control engine temperature. One important area of cooling system operation is warm-up, during which fluid flow is regulated between the bypass and radiator loops. A fundamental question arises regarding the usefulness of the common thermostat valve. In this paper, four different thermostat configurations were analyzed, with accompanying linear and nonlinear control algorithms, to investigate warm-up behaviors and thermostat valve operations. The configurations considered include factory, two-way valve, three-way valve, and no valve. Representative experimental testing was conducted on a steam-based thermal bench to examine the effectiveness of each valve configuration in the engine cooling system. The results clearly demonstrate that the three-way valve has the best performance as noted by the excellent warm-up time, temperature tracking, and cooling system power consumption.
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"Coaxial Probe Fed Modified Sierpinski Fractal Antenna for Wireless Applications." International Journal of Engineering and Advanced Technology 9, no. 2 (December 30, 2019): 2754–57. http://dx.doi.org/10.35940/ijeat.a9773.129219.
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A modified Sierpinski fractal antenna has been designed for wireless applications. The designed antenna exhibits multiple resonance behavior due to the basic attributes of the fractal shapes. The proposed antenna has planar, compact in size and is suitable for various wireless applications. It is designed on the Flame Retardant epoxy board substrate (FR4), which is very easily available, light in weight and has less cost. IFS (Iterated Function System) methodology is accustomed to generate the complex fractal layout using the scripting methodology (.vbs) in the HFSS simulator. Scripting method provides a straight forward solution to generate complicated fractal structures by generating code in MATLAB. The proposed antenna resonates at five different frequencies 1.859 GHz, 3.623 GHz, 5.929 GHz, 9.095 GHz and 9.547 GHz with smart values of return loss up to - 26 dB. It additionally demonstrates good radiation properties and has VSWR values less than two for all resonating frequencies. Radiation characteristics are displayed by 2D and 3D radiation patterns. It also has an low profile value of Gain of 3 dB.
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Vashi, Ronak, Trushit Upadhyaya, and Arpan Desai. "Graphene-based wide band semi-flexible array antenna with parasitic patch for smart wireless devices." International Journal of Microwave and Wireless Technologies, March 12, 2021, 1–9. http://dx.doi.org/10.1017/s1759078721000179.
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Abstract In this paper, a semi-flexible 2 × 1 array antenna is proposed with epoxy glass fiber and graphene as patch and ground, respectively. Microstrip patch antenna with a center parasitic patch of half-wavelength and slot in the radiating patch have been incorporated for the bandwidth enhancement in order of 79.56% (2.21–5.13 GHz). The antenna has an overall size of 0.30λ × 0.24λ at a lower frequency of operation (2.45 GHz). The incorporation of slotted Graphene in radiating element leads to a wideband regime with satisfactory gain values of 2.73 and 3.744 dBi at 2.40 and 4.0 GHz, respectively. Antenna radiation efficiency in the range of 78% with linear polarization makes the antenna appropriate for WLAN band and smart wireless devices application.
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"Evaluation of a Double Pipe Heat Exchanger by using Double Elliptical Leaf Strips with Opposite Orientation and Same Direction and Executing with a Smart Prediction Tool of GRNN." International Journal of Recent Technology and Engineering 8, no. 3 (September 30, 2019): 1790–96. http://dx.doi.org/10.35940/ijrte.c4607.098319.
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The world is full of applications with heat exchangers. From the moment a person wakes up to the end of the day everyone is surrounded by heat exchangers. The refrigerators, Air conditioners, automobile radiators, geysers, Sea breeze etc., are the common applications of heat exchangers .Since we are followed by various devices of heat exchangers so change in the output of heat exchangers would gear up the entire applications and change the society into a new phase. This paper aims at one such augmentation method of insertion of elliptical leaf strip in a heat exchanger equipment for the enhancement of thermal performance of the heat exchanger. From the obtained results of experiment a statistical tool of GRNN is used to compare them. Based on both the available values plotting is done to find the percentage of errors between the calculated values.
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Pedreira, O., C. Papadacci, S. Chatelin, M. Correia, M. Tanter, G. Goudot, E. Messas, and M. Pernot. "Smart ultrasound device for real-time myocardial stiffness quantification of the human heart." European Heart Journal - Cardiovascular Imaging 22, Supplement_1 (January 1, 2021). http://dx.doi.org/10.1093/ehjci/jeaa356.008.
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Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): ERC Introduction Myocardial stiffness (MS) is crucial to understand cardiac biomechanics and evaluate cardiac function. We recently demonstrated that shear wave imaging using acoustic radiation force can provide quantitative end-diastolic MS in human patients [1] . However, the dependence of shear wave velocity with myofiber orientation remained a limitation and required to perform Shear Wave Velocity (SWV) estimations from different probe orientations which is challenging in clinical practice. We propose a new approach to provide real-time quantitative assessment of MS without dependence of the probe orientation based on a dedicated smart ultrasound (US) device. Methods A new US probe was designed and manufactured to generate acoustic radiation force along the central axis and track the SWV simultaneously along three different orientations to obtain an elliptic profile of SWS. The probe was connected to dedicated electronics and software to provide real-time end-diastolic MS with ECG gating. Validation was performed on 4 in-vitro calibrated phantoms (0.92 – 1.49 – 2.58 – 3.49 m/s) and on ex vivo porcine hearts. MS along and across the fibers were compared to the values measured by conventional shear wave imaging with a linear probe mounted on a rotation motor (angular step of 10°) (Aixplorer, Supersonic imaging). Finally, the in vivo feasibility and reproducibility of measuring MS of the antero-septal wall and of the right ventricular (RV) wall was assessed transthoracically on four human volunteer . Results In vitro results on phantoms showed a good agreement with calibrated value (r2 = 0.98, std = 4.8%). Elliptic profiles on ex-vivo porcine heart showed good agreement with Aixplorer measurements acquired at different angles, with a relative difference along the long axis (LA) of: Δ=7.0%, Δ=7.1%, Δ=9% respectively for left ventricle (LV), right ventricle (RV) and septum. Finally, myocardial SWV assessment in human volunteers was obtained successfully on the RV and on the septum in late diastole. The mean MS was 1.79+/- 0.15 m/s along the fiber direction, the fractional anisotropy (FA) was 0.25 +/- 0.06 on septal wall in good agreement with previous results [1] and 1.06 +/- 0.11 m/s along fibers orientation and a FA of 0.27 +/- 0.08 on RV. Finally the beat to beat reproducibility of MS measurement was estimated to be 8.22%. Conclusion The new smart US device allowed non-invasive quantification of anisotropic myocardial tissues in real time. Results showed the accuracy of the methods. This approach could offer a new clinical tool for the evaluation of the myocardium in cardiomyopathies and in heart failure patients. Abstract Figure. SWV on myocardium human volonteer
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Lavarenne, Jean H. J., Evaldas Bubelis, Una Davies, Simone Gianfelici, Solène Gicquel, Jiri Krepel, Marc Lainet, et al. "Burn-Up Dependent Modelling of Fuel-To-Clad Gap Conductance and Temperature Predictions for Mixed-Oxide Fuel in the ESFR-SMART Core." Journal of Nuclear Engineering and Radiation Science, March 12, 2021. http://dx.doi.org/10.1115/1.4050479.
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Abstract Accurate coupled neutronic-thermal-hydraulic analysis of SFRs requires an accurate calculation of the fuel-to-clad gap conductance. In this paper, the gap conductance of the ESFR-SMART MOX pins is investigated through modelling in seven independent fuel performance codes, to provide confidence in results and understand the uncertainties associated with the predictions. This paper presents a comparison of the conductance and predicted fuel temperature distribution between codes. The values produced from the codes are then combined to produce a best-estimate prediction of the gap conductance expressed as a function of nodal fuel rating and burn-up for all seven codes. A fit was applied to the data thus obtained. The spread between results is such that, to 95% confidence, conductance predictions may vary from the correlation by up to a factor of ~4. The gap conductance results show a general increase of conductance with fuel rating and burn-up, from 0.22 at 0 burn-up and 10 kW.m^(-1) to 0.45 at 0 burn-up and 50 kW.m^(-1) and to 1.00 W.?cm?^(-2).K^(-1) at 150 GWd.t^(-1) and 50 kW.m^(-1). Some spread between codes has been noted and appears to be consistent with the spread previously published. There is good agreement between codes at low burn-up for fuel temperature predictions. The spread between codes increases with burn-up due to multiple phenomena including JOG formation and clad swelling.
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Shuravin, Alexander Petrovich, and Sergey Valentinovich Vologdin. "STUDIES OF JOINT WORK OF GENETIC ALGORITHM AND COORDINATE SEARCH ALGORITHM TO OPTIMIZE TEMPERATURE OF HEATED INDOOR AREAS." Vestnik of Astrakhan State Technical University. Series: Management, computer science and informatics, October 25, 2019, 59–69. http://dx.doi.org/10.24143/2072-9502-2019-4-59-69.
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The article is focused on studying optimization algorithms that are relevant both for solving applied problems and for studying the artificial intelligence in general. Optimization methods are used to solve environmental problems including the issues of energy saving. It is important to solve problems of optimizing the thermo-hydraulic modes of buildings (as a part of the “Smart City” project), in particular, problems of eliminating temperature imbalance in terms of saving thermal energy and improving the microclimate in apartments. There is shown a mathematical formulation of the problem of optimizing the temperature modes of the indoor areas using adjustable devices. A hybrid algorithm applied to solve the problem has been described. The considered algorithm combines two optimization methods: a coordinate search method and a genetic algorithm. Thus, the stochastic component (element of the genetic algorithm) and the gradient component (element of the coordinate search method) are used in the hybrid algorithm. A description of the above algorithms is given including the mathematical apparatus used and the design formulas. The results of the numerical experiment for the suggested algorithm are presented. These results are compared with the results of applying the genetic algorithm and the method of coordinates search separately. There has been confirmed the hypothesis that in order to increase the efficiency of solving the considered class of problems, it is necessary to combine the genetic algorithm and gradient methods. At the same time, it has been inferred that in cases of low thermal power of radiators, optimization of the hydraulic resistance of valves is not sufficient, thermal insulation measures and replacement of radiators are also required. The practical value of the work lies in the possibility of solving the problem of saving thermal energy in the housing and communal services system.