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A simple relationship is proposed to construct constant-damage energy factor (γDI) spectra of single-degree-of-freedom (SDOF) oscillators with different levels of damage, expressed by the Park-Ang damage index. γDI is computed for SDOF oscillators with four hysteretic models when subjected to 80 pulse-like ground motions. The statistical dependence of γDI on initial period, damage index, postyield stiffness ratio, and ultimate ductility factor is investigated. In comparison with the non-pulse-type ground motions, the near-fault pulse-type ground motions can significantly increase the γDI of structures, and the magnitude of the increase can reach about 200%. Conservative estimates of mean γDI of SDOF oscillators are proposed taking into account the combined effect of period, damage level, and ultimate ductility factor. [ABSTRACT FROM AUTHOR]

The important indications for assessing CCHP (combined cooling, heating and power) systems are their supply-demand matching characteristics between the user demand side and the energy supply side. These characteristics are primarily influenced by different building types and operating strategies. In view of the energy redundancy of the following electric load (FEL) and following thermal load (FTL) operation strategies and the energy deficiency of the following hybrid electric-heating load (FHL) operation strategy, this paper proposes an improved following balanced heat-electrical load (IFBL) operation strategy based on the following balanced heat-electrical load (FBL) operation strategy. Based on the energy utilization rate as the objective function, this paper optimizes the installed capacity of CCHP systems in different buildings and proposes an energy factor for evaluating the supply-demand matching characteristics of the system. The results show that the energy utilization rate and energy factor of the system under IFBL are optimal relative to the other operation strategies. Secondly, the hotel building has the highest energy utilization rate and the lowest energy factor; on the contrary, the office building has the lowest energy utilization rate and the highest energy factor. Finally, the analysis of supply-demand matching for different building types under multiple operating strategies shows that the hospital and hotel systems exhibit optimal supply-demand matching performance under the IFBL strategy, with values of 0.945 and 0.938, respectively; on the contrary, the office system has an optimal supply-demand matching of 0.935 under the FEL strategy. Under the FTL strategy, the systems of all three buildings exhibit poor matching performance. [ABSTRACT FROM AUTHOR]

The rational allocation of industrial factors in resource-based cities is a necessary condition for promoting high-quality economic development. To systematically measure the mismatch of industrial factors, this study integrates the production function model and accounting framework of Aoki (2012). The capital, labor, and energy factors are integrated into the overall measurement framework, and the factor mismatch calculation model is innovatively constructed at the city level. To effectively reflect the factor mismatch of different cities, the relative distortion coefficient of factor price is introduced to establish the relationship between the distortion of factor-use cost and effectiveness of resource allocation. The degree and direction of factor mismatch are effectively measured. This study takes China's resource-based cities as the research object. To avoid the impact of the COVID-19 pandemic, data on 114 resource-based cities in China from 2003 to 2018 are selected, and 164 non-resource-based cities are used as the control group to evaluate the factors affecting the transformation of such cities. Regarding the diversity of resource-based cities in China, this study compares the characteristics of factor misallocation in these cities for different growth stages, geographical regions, and dominant resources. Finally, this study finds that on average, the cities' degree of energy misallocation is the most serious, and the degree of labor misallocation ranks second. The degree of capital misallocation ranks the lowest, but the misallocation of various factors is very different in different situations. Therefore, different types of cities should make detailed policy adjustments in various transformation directions according to the calculation results.

The influences of applied pressure on the structure, mechanics, dislocation, and electronics properties of an FeTi hydrogen storage alloy are theoretically investigated via first-principles calculations. The lattice parameter ratio, elastic constant, Young's modulus, bulk modulus, shear modulus, ductile/brittle, Poisson's ratio, anisotropy, Cauchy pressure, yield strength, Vickers hardness and energy factor are discussed versus applied pressure. The results show that the FeTi alloy exhibits good mechanical stability under applied pressure between 0 and 50 GPa, and the mechanical properties are significantly improved under applied pressure, like the resistances to elastic, bulk, and shear deformations, the material ductility and metallicity, as well as Vickers hardness and yield strength. Moreover, the electronic structures reveal that the FeTi alloy has metallic properties and the structural stability of the FeTi hydrogen storage alloy is enhanced at high pressure. This work provides significant value for high-pressure applications of FeTi alloys in hydrogen storage and supply fields. [ABSTRACT FROM AUTHOR]

Effects of Al and La elements on mechanical properties of CoNiFe0.6Cr0.6 high-entropy alloys (HEAs) with face-centered cubic (FCC) structure were investigated by first-principles calculations. The variation curves of relevant physical parameters, including lattice constants, formation enthalpy, elastic constants, elastic modulus, Poisson's ratio, Pugh's ratio, Cauchy pressure, anisotropy factors, Vickers hardness, yield strength, and energy factor, as a function of Al and La concentration were discussed in detail. Results show that the resistances to bulk, elastic, and shear deformation decrease with the increase of Al and La concentration. The addition of Al and La can improve the plasticity and ductility of HEAs. Meanwhile, with the increase of Al and La concentration, the metallic characteristic of atomic bonding strengthens and the anisotropy of materials increases. Moreover, the energy factor indicates that the addition of Al and La could promote dislocation nucleation. This study provides a guideline for further research on non-equiatomic CrFeCoNi series HEAs with designed mechanical properties.

Important for promoting the integrated protection and systematic management of mountains, rivers, forests, farmlands, lakes, grasslands, and sandy areas, ecological networks form the backbone of the regional ecological security pattern. An improved morphological spatial pattern analysis coupled with a minimum cumulative resistance model (MSPA–MCR) based on multi-source data was used to study, on a provincial scale, the ecological security pattern of Ningxia, an ecologically fragile region in the upper reaches of the Yellow River in China. The results show the following: (1) A reasonable classification of ecological sources and ecological corridors is key to constructing hierarchical ecological networks. Classifying ecological sources by replacing patch areas with energy factors and identifying the importance of ecological corridors by modifying the gravity model with the energy factors proposed in this paper could improve the rationality of the hierarchical structure division of ecological networks. (2) Grassland as the substrate vegetation type is an important ecological source type in arid and semi-arid ecologically fragile areas, and forests and lake wetlands are the main ecological source types in mountainous areas and oasis areas, respectively. The study area was located in the arid–semi-arid transitional area, with a variety of ecological types, such as mountain, oasis, and desert. Therefore, the complex ecological source types of forest–grassland–wetland appear in some areas. (3) There are 45 ecological patch groups that can be classified as ecological sources in Ningxia, including 10 primary source groups. The number of primary source groups is small, and their spatial distribution is unbalanced. There are two categories of ecological corridors, the river corridor and the mountain corridor, and the network connectivity is poor. (4) The ecological network structure of Ningxia is presented as an ecological security structure consisting of one belt, three screens, three corridors, and five clusters, forming a hierarchical nested ecological network security structure system. [ABSTRACT FROM AUTHOR]

This paper describes a dynamic and quantitative method of diagnosing and estimating rail corrugation in railway tracks using acceleration data obtained from high-speed comprehensive inspection train. Although the amplitude of rail corrugation is small, it will arouse violent vibration between the wheel and rail under high-speed conditions, and accelerate the structural damage of track-vehicle system components. Combined with high-frequency Axle Box Acceleration (ABA), a time-frequency analysis-based Rail Corrugation Index and Energy Factor method are proposed to diagnose the rail corrugation of high-speed railway. The corrugation amplitude is estimated by the quadratic integral of filtered ABA. The new evaluation method uses the windowed energy index signal of the ABA to replace the original signal, and demodulates the high-frequency discrete response signal into a stable low-frequency energy signal without losing the vibration characteristics. Inverse SSTFT is applied to estimate the amplitude of rail corrugation. High-speed railway application results show that the proposed index can effectively diagnose the rail corrugation dynamically and quantitatively and estimate the degree of it. [ABSTRACT FROM AUTHOR]

This paper focused on the performance monitoring and modeling of a 6.0 kW, 2000 L hybrid direct expansion solar assisted heat pump (DX-SAHP) water heater used for the production of hot water in a university students' accommodation with 123 females. The data of total electrical energy consumed, volume of hot water consumed, ambient temperature, relative humidity, and solar irradiance were obtained from the data acquisition systems and analyzed in conjunction with the energy factor (EF) of the system. A multiple linear regression model was developed to predict the EF. The EF of the hybrid DX-SAHP water heater was determined from the summation of the coefficient of performance (COP) of the heat pump unit and the solar fraction (SF) of the solar collectors. The operations of the hybrid energy system were analyzed based on three phases (first phase from 00:00–08:00, second phase from 08:30–18:30, and third phase from 19:00–23:30) over 24 h for the entire monitoring period. The average EF of the hybrid energy system per day during the second phase of operation was 4.38, while the SF and COP were 0.697 and 3.683, respectively. The developed multiple linear regression model for the hybrid DX-SAHP water heater accurately predicted the determined EF. [ABSTRACT FROM AUTHOR]

Weak magnetic detection technology is an effective method to identify stress-induced damage to ferromagnetic materials, and it especially possesses great application potential in long-distance oil and gas pipeline weld crack detection. In the process of pipeline operation, due to internal pressure and external loads, local stress concentration may be generated, and partial stress concentration may lead to local cracks and expansion of the pipe. In order to improve the accuracy of magnetic signal analysis for ferromagnetic materials under internal pressure, the causes of magnetic signal generation at pipeline welds were analyzed from a microscopic perspective. The distributions of magnetic signals at pipeline welds, weld cracks, and base metal cracks under different internal pressures were numerically analyzed. The variation trends of magnetic signal characteristics, such as peak values of axial and radial components, gradient K, maximum gradient Kmax, and gradient energy factor S(K), were analyzed. In addition, experiments were carried out to verify the numerical data. It was revealed that with the elevation of internal pressure, the peak values of the axial and radial components, gradient K, maximum gradient Kmax, and gradient energy factor S(K) linearly increased. However, the magnitude and average change of S(K) were larger, which can more directly indicate variations of magnetic signals. The radial growth rate νy of S(K) was 3.24% higher than the axial growth rate νx, demonstrating that the radial component of the magnetic signal was more sensitive to variations of stress. This study provided a theoretical and experimental basis for detection of stress-induced damage to long-distance oil and gas pipelines. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The influences of applied pressure on the structure, mechanics, dislocation, and electronics properties of an FeTi hydrogen storage alloy are theoretically investigated via first-principles calculations. The lattice parameter ratio, elastic constant, Young’s modulus, bulk modulus, shear modulus, ductile/brittle, Poisson’s ratio, anisotropy, Cauchy pressure, yield strength, Vickers hardness and energy factor are discussed versus applied pressure. The results show that the FeTi alloy exhibits good mechanical stability under applied pressure between 0 and 50 GPa, and the mechanical properties are significantly improved under applied pressure, like the resistances to elastic, bulk, and shear deformations, the material ductility and metallicity, as well as Vickers hardness and yield strength. Moreover, the electronic structures reveal that the FeTi alloy has metallic properties and the structural stability of the FeTi hydrogen storage alloy is enhanced at high pressure. This work provides significant value for high-pressure applications of FeTi alloys in hydrogen storage and supply fields.

Important for promoting the integrated protection and systematic management of mountains, rivers, forests, farmlands, lakes, grasslands, and sandy areas, ecological networks form the backbone of the regional ecological security pattern. An improved morphological spatial pattern analysis coupled with a minimum cumulative resistance model (MSPA–MCR) based on multi-source data was used to study, on a provincial scale, the ecological security pattern of Ningxia, an ecologically fragile region in the upper reaches of the Yellow River in China. The results show the following: (1) A reasonable classification of ecological sources and ecological corridors is key to constructing hierarchical ecological networks. Classifying ecological sources by replacing patch areas with energy factors and identifying the importance of ecological corridors by modifying the gravity model with the energy factors proposed in this paper could improve the rationality of the hierarchical structure division of ecological networks. (2) Grassland as the substrate vegetation type is an important ecological source type in arid and semi-arid ecologically fragile areas, and forests and lake wetlands are the main ecological source types in mountainous areas and oasis areas, respectively. The study area was located in the arid–semi-arid transitional area, with a variety of ecological types, such as mountain, oasis, and desert. Therefore, the complex ecological source types of forest–grassland–wetland appear in some areas. (3) There are 45 ecological patch groups that can be classified as ecological sources in Ningxia, including 10 primary source groups. The number of primary source groups is small, and their spatial distribution is unbalanced. There are two categories of ecological corridors, the river corridor and the mountain corridor, and the network connectivity is poor. (4) The ecological network structure of Ningxia is presented as an ecological security structure consisting of one belt, three screens, three corridors, and five clusters, forming a hierarchical nested ecological network security structure system.

This paper considers the 3D printing process as a discontinuous control system and gives a simple and coherent bond stress-slip model for a new and intelligent building 3-D printed concrete. The previous models focused on either the maximal stress or the maximal slip, however, the novel model uses an energy approach by the dimension analysis, so that the main factors affecting the bond stress-slip relationship can be clearly revealed, mainly including the concrete's properties (its porous structure and its strength), the steel bar's properties (its printing direction, its strength, its surface roughness and its geometrical property) and the printing process. It is confirmed that the proposed model, similar to the constitutive relationship in elasticity, plays a key role in concrete mechanics, and it can conveniently explain the observed phenomena from the experiment. [ABSTRACT FROM AUTHOR]

The manufacturing process of cement emits one metric ton of carbon dioxide greenhouse gas. Considering the situation reducing the gas emission without affecting cement production, industrial wastes like metakaolin (MK) can be partially replaced with cement due to high pozzolanic reactivity to arrive the high-strength concrete. This present examination attentions on the obtaining optimum percentage of metakaolin to be substituted for cement proportion and aims to determine the concrete sample’s mechanical characteristics, equivalent CO _2 emissions, and energy factor for environmental advantages through comparison with metakaolin varied from 0% to 20% at 5% incremental rate was determined and compared with the conventional control mix. Concrete samples are tested at the periodical interval of 7, 14, and 28 days in addition results, 5% of metakaolin is the optimum percentage to be replaced for cement in concrete. The negative sign implies that replacing binder with MK gradually decreases energy requirements (−2.16% to −7.74%) as well as carbon dioxide emissions (−4.17% to −15.41%). The use of mineral admixture like high reactive metakaolin additional cementitious elements has a considerable effect and may have an impact on the creation of environmentally friendly, sustainable concrete. In conclusion, effective utilization of high reactive metakaolin in high-strength concrete leads to substantial cost, and reducing global gas emissions eventually reduces energy consumption and a notable decrease in environmental pollution.

This paper focused on the performance monitoring and modeling of a 6.0 kW, 2000 L hybrid direct expansion solar assisted heat pump (DX-SAHP) water heater used for the production of hot water in a university students’ accommodation with 123 females. The data of total electrical energy consumed, volume of hot water consumed, ambient temperature, relative humidity, and solar irradiance were obtained from the data acquisition systems and analyzed in conjunction with the energy factor (EF) of the system. A multiple linear regression model was developed to predict the EF. The EF of the hybrid DX-SAHP water heater was determined from the summation of the coefficient of performance (COP) of the heat pump unit and the solar fraction (SF) of the solar collectors. The operations of the hybrid energy system were analyzed based on three phases (first phase from 00:00–08:00, second phase from 08:30–18:30, and third phase from 19:00–23:30) over 24 h for the entire monitoring period. The average EF of the hybrid energy system per day during the second phase of operation was 4.38, while the SF and COP were 0.697 and 3.683, respectively. The developed multiple linear regression model for the hybrid DX-SAHP water heater accurately predicted the determined EF.

Weak magnetic detection technology is an effective method to identify stress-induced damage to ferromagnetic materials, and it especially possesses great application potential in long-distance oil and gas pipeline weld crack detection. In the process of pipeline operation, due to internal pressure and external loads, local stress concentration may be generated, and partial stress concentration may lead to local cracks and expansion of the pipe. In order to improve the accuracy of magnetic signal analysis for ferromagnetic materials under internal pressure, the causes of magnetic signal generation at pipeline welds were analyzed from a microscopic perspective. The distributions of magnetic signals at pipeline welds, weld cracks, and base metal cracks under different internal pressures were numerically analyzed. The variation trends of magnetic signal characteristics, such as peak values of axial and radial components, gradient K, maximum gradient Kmax, and gradient energy factor S(K), were analyzed. In addition, experiments were carried out to verify the numerical data. It was revealed that with the elevation of internal pressure, the peak values of the axial and radial components, gradient K, maximum gradient Kmax, and gradient energy factor S(K) linearly increased. However, the magnitude and average change of S(K) were larger, which can more directly indicate variations of magnetic signals. The radial growth rate νy of S(K) was 3.24% higher than the axial growth rate νx, demonstrating that the radial component of the magnetic signal was more sensitive to variations of stress. This study provided a theoretical and experimental basis for detection of stress-induced damage to long-distance oil and gas pipelines.

The rational allocation of industrial factors in resource-based cities is a necessary condition for promoting high-quality economic development. To systematically measure the mismatch of industrial factors, this study integrates the production function model and accounting framework of Aoki (2012). The capital, labor, and energy factors are integrated into the overall measurement framework, and the factor mismatch calculation model is innovatively constructed at the city level. To effectively reflect the factor mismatch of different cities, the relative distortion coefficient of factor price is introduced to establish the relationship between the distortion of factor-use cost and effectiveness of resource allocation. The degree and direction of factor mismatch are effectively measured. This study takes China's resource-based cities as the research object. To avoid the impact of the COVID-19 pandemic, data on 114 resource-based cities in China from 2003 to 2018 are selected, and 164 non-resource-based cities are used as the control group to evaluate the factors affecting the transformation of such cities. Regarding the diversity of resource-based cities in China, this study compares the characteristics of factor misallocation in these cities for different growth stages, geographical regions, and dominant resources. Finally, this study finds that on average, the cities' degree of energy misallocation is the most serious, and the degree of labor misallocation ranks second. The degree of capital misallocation ranks the lowest, but the misallocation of various factors is very different in different situations. Therefore, different types of cities should make detailed policy adjustments in various transformation directions according to the calculation results., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Runqun Yu reports financial support was provided by Liaoning Social Science Planning Fund Office., (© 2024 The Authors.)

Video processing software is often used to remove specific moving foreground from a video. Existing forgery algorithms for detecting this type of tampering generally suffer from inefficiency and are not effective for the forged videos under complex background. To address these problems, we propose a novel forgery detection algorithm for detecting video foreground removal. The algorithm first calculates the energy factor (EF) of each frame to identify forged frames. An adaptive parameter-based visual background extractor (AVIBE) algorithm is then designed to detect suspected regions from the forged frames determined in the first stage. After eliminating false detection by calculating the difference of EF between suspected regions in the forged frames and the corresponding regions in the authentic frames, the algorithm finally locates the tampering traces. The experimental results show that our proposed algorithm has higher computational efficiency and accuracy as well as better robustness than those of previous algorithms.

The utilization of a hybrid energy system (combined solar water heater (SWH) and an air source heat pump (ASHP) water heater) can result in over 80% reduction in the electrical energy consumed as the system is capable to operate with an energy factor of above 4.0. A major challenge is to develop credible methodology or mathematical model to predict energy savings. The research focused on the design and installation of a hybrid energy system and a data acquisition system to monitor its performance. The average weekday volume of hot water consumed, thermal energy gained by water in the tank of the air source heat pump (ASHP) water heater, electrical energy consumed, and the COP were 225.03 L, 5.25 kWh, 1.52 kWh, and 3.50. The average weekday global solar radiation, ambient temperature, solar fraction of the solar water heater (SWH) and the energy factor of the hybrid energy system were 579.67 W/m2, 23.58°C, 0.52, and 4.02, respectively. A multiple linear regression model was developed to predict the energy factor of the hybrid energy system. Both the modelled and validated results showed very good determination coefficients of 0.952 and 0.935, with the trained and validated dataset. Hence, by employing both multiple linear regression model and a multiple 2D contour plot simulation, the energy factor and the variation of the input parameters can be accurately determined. The developed model can help homeowners, energy service companies, and policy makers to appreciate and confidently support the rollout of the technology for sanitary water heating.

The utilization of a hybrid energy system (combined solar water heater (SWH) and an air source heat pump (ASHP) water heater) can result in over 80% reduction in the electrical energy consumed as the system is capable to operate with an energy factor of above 4.0. A major challenge is to develop credible methodology or mathematical model to predict energy savings. The research focused on the design and installation of a hybrid energy system and a data acquisition system to monitor its performance. The average weekday volume of hot water consumed, thermal energy gained by water in the tank of the air source heat pump (ASHP) water heater, electrical energy consumed, and the COP were 225.03 L, 5.25 kWh, 1.52 kWh, and 3.50. The average weekday global solar radiation, ambient temperature, solar fraction of the solar water heater (SWH) and the energy factor of the hybrid energy system were 579.67 W/m2, 23.58°C, 0.52, and 4.02, respectively. A multiple linear regression model was developed to predict the energy factor of the hybrid energy system. Both the modelled and validated results showed very good determination coefficients of 0.952 and 0.935, with the trained and validated dataset. Hence, by employing both multiple linear regression model and a multiple 2D contour plot simulation, the energy factor and the variation of the input parameters can be accurately determined. The developed model can help homeowners, energy service companies, and policy makers to appreciate and confidently support the rollout of the technology for sanitary water heating. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Data Acquisition & Processing / Shu Ju Cai Ji Yu Chu Li is the property of Editorial Department of Journal of Nanjing University of Aeronautics & Astronautics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Energy required for water heating accounts for approximately 40percent of national residential natural gas consumption in California. With water heating contributing such a substantial portion of natural gas consumption, it is important to pay attention to water heater efficiencies. This paper reports on an investigation of a patented, buoyancy-operated flue damper. It is an add-on design to a standard atmospherically vented natural-draft gas-fired storage water heater. The flue damper was expected to reduce off-cycle standby losses, which would lead to improvements in the efficiency of the water heater. The test results showed that the Energy Factor of the baseline water heater was 0.576. The recovery efficiency was 0.768. The standby heat loss coefficient was 10.619 (BTU/hr-oF). After the damper was installed, the test results show an Energy Factor for the baseline water heater of 0.605. The recovery efficiency was 0.786. The standby heat loss coefficient was 9.135 (BTU/hr-oF). The recovery efficiency increased 2.3percent and the standby heat loss coefficient decreased 14percent. When the burner was on, the baseline water heater caused 28.0 CFM of air to flow from the room. During standby, the flow was 12.4 CFM. The addition of the damper reduced the flow when the burner was on to 23.5 CFM. During standby, flow with the damper was reduced to 11.1 CFM. The flue damper reduced off-cycle standby losses, and improved the efficiency of the water heater. The flue damper also improved the recovery efficiency of the water heater by restricting on-cycle air flows through the flue. With or without the flue damper, off-cycle air flow up the stack is nearly half the air flow rate as when the burner is firing.

This study quantifies the potential of a 4.0 kW air source heat pump (ASHP) unit retrofitted to a 12.0 kW, 1000 L electric boiler coupled to a 1000 L storage tank. A data acquisition system was built to monitor the performance of the electric boiler and the ASHP water heater. The annual electrical energy saving and the load factor reduction from the electric boiler because of the ASHP unit retrofit was 34,805.94 kWh and 0.124. The net present value payback period of the ASHP system was 1.60 years. A Wilcoxon rank sum test was employed to compare both the volumes of hot water and electrical energy consumed by the two systems. Linear regression models of the daily volumes of hot water and electrical energy consumed by both systems were established. The results should be of great value to the management of universities that are considering energy-efficient interventions with a significant return on investment.

The increase in the number of space debris is a serious threat to the safe operation of in-orbit spacecraft. The propagation law of the impact signal in the stiffened panel of the spacecraft's sealed bulkhead is very complicated, and there is less research on the impact source location in the high-stiffened panel. In this paper, an adaptive energy compensation threshold filtering (AECTF) method based on acoustic emission is proposed, which can realize large-scale, fast and accurate locating of the impact source on the stiffened panel with less resource consumption. The influence law of the stiffeners on the lamb wave is analyzed by finite element simulation, and the Lamb wave energy factor curve is obtained. The correctness of the simulation is verified by the locating experiment on the impact point. The results show that the proposed AECTF method has better adaptability and can correctly locate the impact points in complicated locations. By selecting the appropriate frequency band to filter the signal, the locating accuracy and stability can be improved. When the frequency band is 100–200 kHz, the locating result is optimal, the average absolute error is 7.0 mm, the average relative error is 0.86%, and the error standard deviation is 3.5 mm. This study will generate fresh insight into the impact location technology of high-stiffened panel and provide a reference for the in-orbit spacecraft health monitoring system. [ABSTRACT FROM AUTHOR]

Comprehensively evaluating the accuracy of the digital elevation model (DEM) upscaling methods is significant for us to choose the DEM upscaling method reasonably, master the DEM up-scaling law, and construct a new DEM upscaling model. However, the current researches on DEM accuracy evaluation are still not sufficient to meet the requirements of practical applications. In this paper. an accuracy assessment method for DEM based on energy factor is proposed and then is applied to the accuracy assessment of different DEM upscaling methods. A comprehensive evaluation strategy combining qualitative and quantitative accuracy assessment and quality evaluation methods is constructed to verify the rationality and effectiveness of the assessment strategy based on energy factor. The experimental results show that the accuracy assessment method based on energy factor is simple in theory and is easy to operate in practice. It can reflect the retention characteristics of the terrain masking relationship of the upscaling methods, whereas the traditional precision evaluation strategy cannot reflect them directly. This accuracy assessment framework also provides a new and valuable standard for choosing the DEM upscaling methods, and puts forward new design requirements for the DEM upscaling methods. It also has great influence on remote sensing modeling and inversion. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Energy factors were obtained for gasoline and ethanol fueled engines and vehicles. • Use of 3D engine BFSC maps produced consistent results for flexible fuel engines. • Energy conversion factor for E22 was 0.43 L/kW h, from laboratory and road tests. • Energy conversion factor for E100 was 0.62 L/kW h, from laboratory and road tests. Abstract This work investigates the energy factors for fuel conversion from the analysis of brake specific fuel consumption (BSFC) maps of a sample of 15 engines, representative of 75% of current models available in the Brazilian market. The method also employs the engine driving patterns of power output versus crankshaft speed obtained from bench dynamometer tests. The energy factors obtained from the engine analysis was validated against experiments carried out with two production vehicles in laboratory tests following the 1975 US Federal Test Procedure (FTP-75) procedure and road tests following 16 different urban and highway routes. The fuels used in the tests were hydrous ethanol (E100, 6 v/v % water) and a blend of 22 v/v % anhydrous ethanol and 78 v/v % gasoline (E22). The energy factors found from the 3D engine BSFC map analysis were higher than those obtained from the Willans line, currently adopted as a standard, by 52% for E22 and 57% for E100. The results from the 3D engine BFSC maps and the first vehicle following the FTP-75 cycle and 15 road routes were similar, also close to the results from the second vehicle, qualifying them to be representative of modern flexible fuel spark ignition engines and vehicles. [ABSTRACT FROM AUTHOR]

Abstract This study focuses on the energy factor demand of oscillators with the modified Clough hysteretic model subjected to pulse-like near-fault ground motions. First, the definition of the energy factor demand of modified-Clough oscillators was clarified. Then, oscillators covering a reasonable range of nonlinear parameters and dynamic properties were analysed with a constant-ductility-based method, and a ground motion database characterising pulse-like near-fault ground earthquake motions was used as seismic excitations. The influence of the hysteretic quantities on the energy factor demand of the modified-Clough oscillators was discussed based on the statistical results. Comparison between the energy factor demand from the analysis database and the counterparts computed based on the widely used Newmark-Hall model was made. Recognising the limitations of the current design model, an alternative design equation for estimating the mean energy factor demand of oscillators with the modified Clough hysteretic model was proposed using nonlinear regression analyses. The improved accuracy of the developed model was demonstrated. The research findings of this work provide a basis for energy-balance-based seismic design of structures whose hysteretic force-displacement response can be idealised with the modified-Clough model. Highlights • The energy factor of oscillators with the modified Clough hysteretic model is quantified. • The influence of hysteretic parameters is investigated. • The applicability of the current design method is evaluated. • An alternative design equation is proposed. [ABSTRACT FROM AUTHOR]

Referenced article is the overview of the important scientific problem – determination of the power industry influence on the US-China international relations within the Persian Gulf region. Persian Gulf region plays a really important role within the system of the global energy security. Hence, high importance is allocated to the power industry as Chinese factor of influence in the Middle East and its role in the US-China international relations. Within the post-bipolarperiod, political influence of China in the Persian Gulf region is substantially growing. US attempts to unilaterally control security in the Gulf is opposed by Chinese establishment of relations with those countries of the region, who are falling within its geopolitical and geoeconomical sphere of interst. It is defined a set of peculiarities of China’s interaction with the other external actors in context of regional rivalry for influence in the region. It is proved that as China, unlike the United States, does not determine a general direction of geopolitical processes in Persian Gulf, US policy in the Region is the main external determinant for Chinese foreign policy strategy formation and implementation, and energy security of China will mostly depend on the level of cooperation and understanding between China and the United States. It is proven that an essential tool for ensuring economic interests of China in Persian Gulf is to prevent strengthening of geopolitical influence of other external actors by creating alternatives based on potential of Chinese economy

The meaning of the energy factor in the system of security US vital interests was investigated. The role of the region’s Gulf states in the energy policy of the United States was defined and the special importance of post-war Iraq in order U.S. energy security was studied. The sense of the energy factor was considered as a foreign policy tool that belong to the elements of «hard power». It was studied the instruments of political and economic cooperation between the USA and Persian Gulf countries. The energy strategy of the United States was detailed analyses, in the framework of which it was comprehensively studied the mechanisms for combating the energy dependence as well as the use of preventive mechanisms of the crisis management in the energy policy. It was defined the policy tools of oil security supply by the states of the Persian Gulf. The role of the US law «No Oil Producing and Exporting Cartels Act of 2007/ HO Congress 2007-2008» as a political tool to ensure oil security of the U.S. was established. It is proved that in conditions of high dependence of the economic system from energy prices in the world market, the oil factor played the dominant factor in the anti-Iraqi company in 2003. It was noted the importance meaning for political stability of Iraq the Bill of Oil, which aimed to facilitate reconciling different religious communities in the country (Sunnis, Shiites and Kurds), through the distribution of state oil income among them.

In the existing key node decision methods for wireless sensor network,the judgment index was so single that the result judged was deficient.In order to solve this problem,a new key node decision algorithm(KNDA)based on local information and energy factor was proposed.Firstly,the local information model based on the degree and neighbor information of node was established.Secondly,according to the residual energy of node and the change of network energy consumption after the node failed,the models of energy factors were established.Finally,an aggregative key node decision model was formed.Extensive simulation experiments were carried out in the MATLAB simulation platform,by comparing with other algorithms,the results verify that the key nodes obtained by this algorithm are more sufficient.Meanwhile when the key nodes judged by KNDA are protected,the network can show strong invulnerability.