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The heating potential of microwave-heated bituminous mixtures depends on the heating characteristics of aggregates. This study focused on understanding the effect of mineral, chemical, and dielectric properties of aggregates on the rate of heating of aggregates, with special emphasis on the effect of the power level of microwave energy. Properties of the aggregates collected from 18 different sources were evaluated using X-ray diffraction, X-ray fluorescence spectroscopy, and a microwave vector network analyzer. Heating studies were conducted on the aggregates using a microwave oven at four different power levels (330, 525, 630, and 700 W). Thermal images, captured using a forward-looking infrared (FLIR) thermal camera, were used to obtain the heating characteristics, such as heating time, rate and nonuniformity of heating. The rate of heating of aggregates (0.212°C/s−1.007°C/s), nonuniformity of heating (0.059°C–0.218°C), and time of heating to 100°C (40–520 s) varied widely with the source of aggregate. In general, the heating rate and the degree of nonuniformity of the aggregates increased with increase in microwave power. Bulk mineralogy and chemical composition of aggregates significantly influenced the dielectric response of aggregates (adjusted R-squared values of 0.75 and 0.70, respectively) and the sensitivity of heating parameters to microwave power (adjusted R-squared values of 0.83 and 0.92, respectively). Two different predictive models were developed for estimation of heating rate of aggregates with (1) power, density, and dielectric loss factor, and (2) power, density, and aggregate chemical indices as independent variables. The adjusted R-squared values of these two predictive models were 0.84 and 0.92, respectively. [ABSTRACT FROM AUTHOR]

The paper considers the problem of energy security as one of the main factors of sustainable development of European countries. Research results indicate that supply security is an important aspect to be considered when identifying threats to Europe's energy security and ways of countering them. It is necessary to develop a method for determining the sustainable power level of the gas transport system, which would reflect the relationship between accidents on main gas pipelines and their economic, environmental and social consequences. The paper presents such a method based on the systematic-functional approach, the decomposition method and the concepts of set theory; its core principles and design are revealed. The informative nature of the power level of the gas transport system development in Ukraine is proved with regards to making regulatory decisions that take into account the economic, environmental and social consequences of their influence. [ABSTRACT FROM AUTHOR]

The fast reactor is gradually being paid attention to in nuclear power due to a better breeding effect, and its economy is also directly followed. Due to the restriction of the core power density, the core power level is directly related to the volume of the core active area. When the power level and the volume of the core gradually increase, the mass of uranium and 235U in the core at the beginning of life will gradually increase on the basis of a critical uranium inventory. At the same time, due to the gradual increase in the breeding effect, the utilization rate of uranium resources at the end of life will gradually increase. Due to the characteristics of the large critical uranium mass and high breeding effect, the mass of uranium and 235U in the low power level core at the beginning of life cannot be further reduced because of the critical uranium inventory. The lifetime of the high power level core should be extended to use the wealthy reactivity of the core because of the improvement in the breeding effect. However, due to the requirements of the nuclear power refuel time and the limitation to fuel consumption, the breeding effect brought by the improvement in the core power level and the size of the active zone may be less effective. In this article, the power level and economy of lead-based modular nuclear power are analyzed, and the economy of different power level fast reactors with 2,000 EFPD lifetime such as 100 MWt, 300 MWt, 500 MWt, 700 MWt, and 1000 MWt thermal power is designed and analyzed. By analyzing the invention of uranium and 235U and the fuel utilization of different core schemes, the best economic analysis of the single reactor power of the current lead-based modular reactor is proposed and the foundation of the lead-based modular nuclear power is provided.

The purpose of this study was to investigate muscle synergies (MS) during upper limb cycling motion across power levels (20, 40, 60, 80, 100, and 120 watts). The MS hypothesis is important to the understanding of modular control for human movements. In this study, we explore its importance in execution of phasic movements at various power levels. Electromyographic (EMG) signals were recorded from 7 upper limb muscles during cycling for 30s on a hand-cycle ergometer. A Non-Negative Matrix factorization (NNMF) algorithm was used to extract MS. Cosine similarity was used to compare the MS and cross-correlation was used to compare activation coefficients. We found that the number and structure of synergies were consistent across power levels while admitting modulation in their activation coefficients. A total of three shared MS explaining ≥95% of the variance accounted for (VAF) represented push and pull mechanism during cyclic motion. [ABSTRACT FROM AUTHOR]

Since the 1990s, mobile telecommunication networks have gradually become denser around the world. Nowadays, large parts of their backhaul network consist of commercial microwave links (CMLs). Since CML signals are attenuated by rainfall, the exploitation of records of this attenuation is an innovative and an inexpensive solution for precipitation monitoring purposes. Performance data from mobile operators’ networks are crucial for the implementation of this technology. Therefore, a real-time system for collecting and storing CML power levels from the mobile phone operator “Telecel Faso” in Burkina Faso has been implemented. This new acquisition system, which uses the Simple Network Management Protocol (SNMP), can simultaneously record the transmitted and received power levels from all the CMLs to which it has access, with a time resolution of one minute. Installed at “Laboratoire des Matériaux et Environnement de l’Université Joseph KI-ZERBO (Burkina Faso)”, this acquisition system is dynamic and has gradually grown from eight, in 2019, to more than 1000 radio links of Telecel Faso’s network in 2021. The system covers the capital Ouagadougou and the main cities of Burkina Faso (Bobo Dioulasso, Ouahigouya, Koudougou, and Kaya) as well as the axes connecting Ouagadougou to these cities.

This research was undertaken to examine the result of microwave pre-treatment on chickpea dehulling. The experiments were conducted at three microwave power levels (PL), 50, 70, and 90, at different five exposers from 1 to 3 minutes at the time interval of 30 seconds to evaluate chickpea dehulling with the pre-milling treatment of microwave exposure for achieving maximum dehulling yield, dhal yield, good dehulled grains in terms of quality with minimum dehulling loss. It was noted that dehulling yield improved with microwave power and exposure period. The highest dehulling yield, 71.02%, was achieved 90 PL with 2.5 minutes exposure and found maximum dhal yields, i.e., 66.40%, and minimum dehulling loss, 10.25%. So, this requirement was correct and better to get a higher dhal yield. These findings are also valuable for the pulse processing industry and fabricators for designing a continuous type pulse pre-milling treater unit. Hence, it could be highlighted that the microwave pre-milling treatment is more suitable for pulse processing like chickpea. This also presents an improvised method for pre-milling treatments for commercial adoption. [ABSTRACT FROM AUTHOR]

In this study, drying kinetics and quality of purple-fleshed sweet potato (PFSP) subjected to microwave-vacuum drying were investigated. The effects of hot water and steam blanching pretreatment on physicochemical characteristics of the dried products were also considered. The samples were dehydrated in a custom-made microwave-vacuum system at different power levels including 450, 600 and 850 W. Hot air drying at 70 °C was also conducted for comparison. The results showed that drying time of PFSP under microwave-vacuum conditions ranged from 6 to 12 min, significantly reduced as compared to that of hot air drying (600 min). The improvement of drying rate was also evidenced by increased effective moisture diffusivity (2.22 × 10−7–4.05 × 10−7 m2/s) of the samples. Drying kinetics of PFSP was best fitted by Page and logarithmic model with R2 ranging from 0.991 to 0.998, and RMSE from 0.016 to 0.030. PFSP dried under microwave-vacuum condition had lower water absorption index and swelling capacity than hot air drying. Color, antioxidant activity and total phenolic content of dried PFSP were also improved under microwave-vacuum drying. The effects of blanching pretreatment on quality of dried PFSP were more dominant in hot air than microwave-vacuum dried samples. [ABSTRACT FROM AUTHOR]

The effects of microwave heating at different processing time and power levels (360 W, 600 W and 900 W) on Salmonella Typhimurium , Escherichia coli O157:H7, Listeria monocytogenes and Staphylococcus aureus in Turkish type meatballs were evaluated. Besides, the changes in the textural and sensorial properties of meatballs were determined to reveal the cooking time and temperatures that would make the product safety without affecting the consumer preferences. In this direction, the experimentally contaminated meatballs were subjected to microwave heating at low, medium and high power levels for different processing times and analysed for the survival of the relevant pathogenic bacteria. The total aerobic bacteria count in meatballs could be reduced approximately 3–4 log CFU/g by medium and high microwave powers, whereas 5–7 log CFU/g inhibition was obtained in meatballs inoculated with pathogens. The increase in power level together with the increasing process time resulted in a decrease in the counts of bacteria and an undesirable effect on the textural and sensorial qualities of meatballs. Microwave heating at medium and high power levels as from 3 min, caused excessive drying and blackening of the product, making it difficult to consume due to crust formation. Consequently, to achieve optimal acceptability of the product by consumers, meatballs should be heated with a microwave power of 600 W and 900 W for 3 min. • Microwave heating of meatballs with a power of 600 W and 900 W may be an alternative pasteurization intervention. • Microwave heating ensures the microbial safety of meatballs. • Microwave treatment at 600 W and 900 W for 3 min maintains the overall food quality. [ABSTRACT FROM AUTHOR]

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control 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.)

In this paper, permutation test of comparing two-independent samples is investigated in the context of extreme ranked set sampling (ERSS). Three test statistics are proposed. The statistical power of these new test statistics are evaluated numerically. The results are compared with the statistical power of the classical independent two-sample t-test, Mann- Whitney U test, and the usual two-sample permutation test under simple random sampling (SRS). In addition, the method of computing a confidence interval for the two-sample permutation problem under ERSS is explained. The performance of this method is compared with the intervals obtained by SRS and Mann-Whitney procedures in terms of empirical coverage probability and expected length. The comparison shows that the proposed statistics outperform their counterparts. Finally, the application of the proposed statistics is illustrated using a real life example. [ABSTRACT FROM AUTHOR]

One of the critical design issues in real‐time systems is energy consumption, especially in battery‐operated systems. Generally higher processor voltage generates higher throughput of the system while decreasing voltage can perform energy minimisation. Instead of lowering processor voltage, this paper presents an optimum energy efficient real‐time scheduling to adjust voltage dynamically to achieve optimum throughput. Earlier research works have considered random new tasks, which have been divided into jobs using pfair scheduling to fit into idle times of different cores of the system. In this paper we consider each job has different power levels and execution time at each power level can be found using normalised execution time. Based on the power levels and their corresponding execution time, we find different combinations of energy signature of the system and derive the optimum state of the system using a weighted average of the energy of the system and corresponding throughput. We verify the proposed model using generated task sets and the results show that the model performs excellently in all the cases and significantly reduced the total energy consumption of the system with respect to some popular and relatively new scheduling schemes. [ABSTRACT FROM AUTHOR]

[Display omitted] • This study investigated the effects of the power level of 915 MHz microwave heating at the same holding time on the bacterial inactivation efficacy. • A holding time of 15 s after 100℃ resulted in a > 5 log reduction with 3–5 kW microwave heating. • Microwave heating led to a significant change in transmembrane potential by increasing power level and caused damage to>86% of the DNA at power levels of 2–5 kW. • Severe cell membrane damage in Listeria monocytogenes due to non-thermal effects was observed at 5 kW through transmission electron microscope images. • An increase of the power level influenced the moisture content, cooking loss and texture properties. The main purpose of this research was to investigate the effect of power level of 915 MHz microwave heating on the inactivation of foodborne pathogens in ground pork and its bactericidal mechanism. It was demonstrated that the heating rate was proportional to the power level. For instance, the heating rates observed at microwave heating powers of 2, 3, 4, and 5 kW were 1.70, 2.77, 3.35, and 4.03℃/s, respectively. The bactericidal effect of microwave heating also significantly (P < 0.05) increased with increasing power level. In particular, when ground pork was subjected to microwave heating at 5 kW, the reduction level of pathogens was>2 log units higher than at 2 kW. To determine the bactericidal mechanism of microwave heating depending on power level, changes in transmembrane potential and DNA damage were determined using fluorescence. The extent of depolarization in membrane potential of pathogens significantly (P < 0.05) increased as power level increased. There was no significant difference in degree of DNA damage at different power levels. However, the percentage of DNA damage was>86% at all power levels. The transmembrane potential assay indicates that the bacteria exhibited dramatic pore formation on the membrane at 5 kW. Through transmission electron microscopy, the electroporation effect was enhanced as power level increased. Moreover, the quality of ground pork subjected to microwave heating at 2–5 kW was determined by measuring the moisture content, cooking loss, and texture profile. [ABSTRACT FROM AUTHOR]

The passive intermodulation (PIM) has gradually become a serious electromagnetic interference in the high-power and high-sensitivity RF/microwave communication system with the existence of the nonlinear metal-to-metal (MM) contacts. This paper proposes a finite difference time domain (FDTD) method for PIM analysis of nonlinear MM contacts. There are two kinds of models, the power series model and the equivalent circuit model, to describe the nonlinear MM contacts. Then the FDTD method is applied to analyze the nonlinear models so that the nonlinear current through the MM contact can be determined. For the microwave transmission devices, the PIM power level can be obtained by fast Fourier transform of the nonlinear current. For the microwave radiation devices such as antennas, the nonlinear currents are taken as a new electromagnetic transmitting source, the far-field scattering and PIM power level can be obtained by the FDTD method. Finally, a comparison between the simulation and experimental results is illustrated to verify the validity of the proposed method. [ABSTRACT FROM AUTHOR]

Modular multilevel converters (MMCs) provide advantages to reach medium‐voltage operation increasing the power level in industrial applications. In this study, a tundish induction heating power supply based MMC (MMC‐TIHPS) is investigated for heating molten steel. The equivalent model of MMC‐TIHPS is established and the energy in horizontal and vertical directions are analysed. The heating control for molten steel consists of temperature increasing and constant temperature processes (alternatively called transient‐state and steady‐state operation). The main contribution of this study is to propose a direct power feedforward control based load current feedforward strategy for TIHPS. With this strategy, TIHPS can be controlled operating with full power to heat molten steel in transient state and guarantee the insulation effectiveness in steady state. Proper parameters of controllers are designed. Experimental results are conducted to validate the feasibility of MMC‐TIHPS and the effectiveness of the proposed control method. [ABSTRACT FROM AUTHOR]

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control 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 effects of multi-frequency ultrasound-assisted immersion freezing (MUIF) at different ultrasound power levels (160, 175, and 190 W, respectively) on the quality of large yellow croaker (Larimichthys crocea) during frozen storage were studied. The study found that water loss and texture deterioration of MUIF were lower and MUIF was fresher than immersed freezing (IF) by affecting the morphology of ice crystals. Although the total volatile basic nitrogen (TVB-N) and K values of each treatment increased continuously during frozen storage, MUIF was consistently lower than IF. Among them, MUIF at 175 W (MUIF-175) maintained good quality in frozen storage because of the fine and uniform ice crystals, indicating that MUIF at a specific power level can reduce the quality degradation of the samples during frozen storage. [Display omitted] • MUIF slowed down water loss and texture deterioration during frozen storage. • MUIF improved the freshness of large yellow croaker during frozen storage. • MUIF at 175 W formed fine ice crystals and caused little damage during 300 days. • MUIF at 175 W still had grade I freshness on the 300th day of frozen storage. • MUIF at 175 W had lower water loss and higher sensory scores during 300 days. [ABSTRACT FROM AUTHOR]