Aiming at more and more occasions where the sine wave output inverter is used for power supply of a non-linear load, the sine wave output waveform distortion of the inverter caused by the non-linear ...load is serious. The feedback control strategy of sine wave inverter based on instantaneous reactive power is proposed. Through the fundamental wave instantaneous tracking feedback control based on the instantaneous reactive power theory and the detection and feedback control of the output harmonic signal, this paper realizes the ability of the inverter to maintain the output waveform with high sine degree and low distortion under various load conditions, it guarantees the error-free control of the fundamental wave and has a good dynamic response performance. This solution has the advantages of easy controller stability design and good implementability. The simulation circuit is built by Matlab / Smiulink, and the correctness of the theory is verified by the simulation results.
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•A novel optimization model for the technology portfolios of shale gas development.•Hydraulic fracturing, CO2 fracturing, CO2 injection, and CO2 sequestration are considered.•Case ...studies on non-water sensitive and water sensitive formations are examined.•CO2 injection technique can produce more profit and sequestrate more CO2.•Impacts of incremental gas recovery of CO2 fracturing and carbon price are explored.
Hydraulic fracturing is widely used in shale gas development, while it could cause decline in production in water-sensitive formations. Using CO2 for reservoir fracturing, injection to enhance gas recovery, and sequestration in depleted shale reservoirs can solve this problem, increase shale gas production, and store CO2 underground. Given the high expense of these CO2 techniques, the trade-off between the rising cost of deploying CO2 techniques and the benefit of increased shale gas production influences the technology portfolios for shale gas development. Financial incentives for carbon credits can provide compensation for the cost of CO2 techniques, further influencing the technology portfolios. Currently, questions remain regarding the optimal technology portfolios for achieving cost-effective shale gas development under different reservoir conditions and the impacts of the carbon price incentive. Here, we propose a novel optimization model that simultaneously integrates the hydraulic fracturing, CO2 fracturing, CO2 injection, and CO2 sequestration techniques to investigate the optimal technology mix for cost-effective shale gas development. We select the non-water sensitive formations and water sensitive formations as two representative scenarios. The results show that to cost-effectively develop shale gas, hydraulic fracturing is preferred in the non-water sensitive scenario whereas CO2 fracturing and CO2 injection are preferred in the water sensitive scenario. The synergistic deployment of CO2 fracturing and CO2 injection techniques can not only improve economic performance but also sequestrate more CO2. Our findings provide policy makers with critical insights into achieving cost-effective shale gas development while curbing carbon emissions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Design a micromodel to simulate reservoir fracture to study the mechanism and law of salt precipitation in fracture during CO2 geological storage.•Under hydrophilic conditions, reducing the CO2 ...injection rate and increasing the solution concentration will increase the amount of salt precipitation in the fracture and impair reservoir injectivity.•Increasing the contact angle of the rock will greatly reduce the amount of salt precipitation in the fracture, which is less effect on reservoir injectivity.•Similar conclusions can also be applied to caprock fractures, and the occurrence of salt precipitation in caprock fractures will have the effect of self-healing of the fractures.
Injectivity is an important indicator when it comes to evaluating the geological storage of CO2. It is commonly accepted that salt precipitation damages the injectivity during the CO2 injection process. Numerous studies have been conducted on the salt precipitation mechanism in homogeneous reservoirs. However, the mechanism of salt precipitation in fractures during CO2 injection and its influence on the injectivity need to be studied in depth. Therefore, in this study, a micromodel that simulates a reservoir fracture was designed and pore-scale experiments were conducted to study the effects of the CO2 injection rate, the concentration of the solution, and the rock's wettability on the salt precipitation in the fracture. It was found that under hydrophilic conditions, reducing the CO2 injection rate and increasing the concentration of the solution increased the amount of salt precipitation in the fracture and impaired the micromodel's injectivity. In contrast, increasing the CO2 injection rate and the contact angle of the rock greatly reduced the amount of salt precipitation in the fracture, which had a less adverse effect on the micromodel's injectivity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
As a herbal medicine, the extract from the fruits of Gardenia florida has been widely used for its antioxidative, hypoglycemic, and anti-inflammatory properties. However, whether G. florida fruit ...extract (GFFE) regulates hair growth has been rarely studied. This study was the first application of GFFE on hair growth both in vitro (human dermal papilla cells, hDPCs) and in vivo (C57BL/6 mice). The effects of GFFE on cell proliferation and hair growth-associated gene expression in hDPCs were examined. Moreover, GFFE was applied topically on the hair-shaved skin of male C57BL/6 mice, the hair length was measured, and the skin histological profile was investigated. GFFE promoted the proliferation of hDPCs and significantly stimulated hair growth-promoting genes, including vascular endothelial growth factor (VEGF) and Wnt/β-catenin signals, but suppressed the expression of the hair loss-related gene transforming growth factor-β1 (TGF-β). Furthermore, GFFE treatment resulted in a significant increase in the number, size, and depth of cultured hair follicles and stimulated the growth of hair with local effects in mice. In summary, the results provided the preclinical data to support the much potential use of the natural product GFFE as a promising agent for hair growth.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK, VSZLJ
Background
In traditional Asian medicine, Gynostemma pentaphyllum Makino leaf extract (Gp) is used to treat aging, metabolic syndrome, diabetes, and neurodegenerative diseases. Hair loss and ...hair‐graying are common phenomena that haunt everyone. However, whether Gp activities on inhibition of hair loss and getting gray have been rarely studied.
Aim
Study the Gp activity and mechanism by in vivo and in vitro experiments to explore its application on hair health.
Methods
In the present study, we determined the effects of Gp on the expression of hair growth‐related genes and proliferation of human dermal papilla cells (hDPCs). Furthermore, Gp was topically applied to the hair‐shaved skin of male C57BL/6 mice, and the histological profile of the skin was studied. Because emotional stress may lead to melanocyte disappearance, norepinephrine‐exposed mice B16 melanocytes were treated with Gp to elucidate the anti‐hair graying capacity of Gp in response to this stress type.
Results
Gp stimulated the proliferation of hDPCs and the Wnt signaling pathways associated with hair growth; furthermore, the expression of the hair loss‐related gene transforming growth factor‐β1 was suppressed. Gp treatment significantly increased the size of hair follicles in the treated mice and stimulated them. Moreover, Gp not only increased melanin synthesis but also tyrosinase activity in B16 cells. Quantitative real‐time polymerase chain reaction revealed that Gp increased melanin synthesis by increasing the expression of tyrosine‐related protein‐1, tyrosine‐related protein‐2, tyrosinase, and microphthalmia‐associated transcription factor.
Conclusion
Our study provides preclinical evidence regarding the potential of Gp as a promising hair growth and anti‐graying agent.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
As the increasing usage scenarios of tablet computers led to more non-neutral postures, optimizing the touchscreen gesture input became imminent to improve system performance and users' well-being. ...Therefore, we conducted a study to investigate the influence of four tablet configurations and seven touchscreen gestures on electromyography, performance, and subjective assessment. Our results indicated that muscular loads of shoulder decreased under the Stand-Hand configuration while it increased under the Sit-Table during gesture interaction. We also found that Drag-Up and Drag-Left tended to possess higher muscular loads of shoulder while Drag-Down caused greater muscular loads of index finger. Besides, two-touch gestures spent longer duration when performing long-distance movements. Dragging in the inner direction was supposed to be more efficient than that in the outer direction. Our findings could provide a scientific basis for guiding the appropriate selection and the use of touchscreen interaction in the future HCI field.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
This study presents a novel heat integration model for a gas turbine power plant that enables sustainability through efficient utility generation and production of fresh water. Significant advantage ...of proposed system lies in its utilization of a novel thermal matching method between integrated combined processes, leading to development of an environmentally sustainable multi-generation structure. Consequently, the integrated system includes a Kalina cycle, high- and low-temperature organic Rankine cycles, an absorption chiller, a heating provision unit, and a water desalination subsystem. The simulated procedure utilizes the Aspen HYSYS software and follows with a comprehensive analysis to assess its energy, exergy, economic, and environmental characteristics. The study's findings exhibited net power output, cooling load, heating load, and desalination energy output of 23,924.06 kW, 3486 kW, 6671 kW, and 230.9 kW, respectively. The system's energy efficiency improves from 47.81 % to 68.58 % when operating in single-generation and multi-generation modes. Likewise, the exergy efficiency improves from 45.55 % to 52.42 %. The study also illustrates the carbon dioxide emission intensity associated with both mentioned modes at 0.4187 kg/kWh and 0.2641 kg/kWh, respectively. Besides, the economic evaluation reveals total annual cost, cost of energy, and total cost of products of 147.65 M$/year, 0.5783 $/kWh, and 10.71 $/GJ, respectively.
•Simulation/analysis of a new heat recovery process combined with a gas turbine cycle•The process considers an eco-friendly design for a CCHP-desalination application.•The simulation is conducted by Aspen HYSYS software and is analyzed from 4E aspect.•Total energy and exergy efficiencies are computed at 68.58 % and 52.42 %.•CO2 emission intensity and cost of energy equal 0.2641 kg/kWh and 0.5783 $/kWh.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Research on gesture input modalities, including touchscreen and mid-air interactions, is getting more widespread. A few studies have compared these two input modalities according to subjective ...methods. However, there is no empirical research on their differences in physiological measures. The purpose of this study was to quantify the differences between touchscreen and mid-air interactions when performing swipe gestures in four orthogonal directions on a tablet combining the indices of electromyography (EMG), electrogoniometry, user performance, and subjective assessment. Our results indicated that mid-air interaction obtained significantly lower muscular loads in the upper limb, smaller wrist joint excursions, shorter task completion time, and better subjective ratings than touchscreen interaction when users with elbow support performed swipe gestures on a tablet. We also found that performing swipe gestures in the vertical direction tended to possess higher muscular loads than in the horizontal direction during touchscreen interaction. Besides, we revealed that swipe right had the largest radial/ulnar deviation, and swipe down had the largest flexion/extension excursion. Furthermore, swipe up brought the worst subjective ratings among the four gesture types. These findings could provide a scientific basis for guiding the appropriate selection and use of the two input modalities in the future HCI field.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Considering the importance of efficient thermal integration for a gas turbine cycle using its energetic flue gas, the current paper proposes an eco-friendly and efficient process integrated into a ...gas turbine cycle. The newly designed polygeneration structure produces power, hot water, and methanol. The components of this system include a heat provider unit, a direct carbon dioxide hydrogenation unit for the production of methanol, an ammonia Rankine cycle, a proton exchange membrane electrolyzer, a supercritical carbon dioxide power cycle, and two organic Rankine cycles. The feasibility of the proposed model is evaluated using a comprehensive multi-variable assessment from energy, exergy, economic, and environmental approaches. This system exhibits a power production capacity of 17197.23 kW and a methanol generation rate of 0.7573 kg/s. Also, the total irreversibility is equal to 68161.18 kW. Besides, the total energy and exergy efficiencies are found as 68.73% and 32.03%, respectively. This model's carbon dioxide emission is 18667.36 kgCO2/h, and its carbon footprint equals 0.2196 kgCO2/kWh. Furthermore, the economic analysis reveals that the project has an annual total cost of 194,602,338 and a net present value of 686,221,616. Besides, the computed total unit costs for products and energy are 0.3385 $/kWh and 89.81 $/GJ, respectively.
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•New heat integration combined with a gas turbine, producing power, heat, and methanol.•Comprehensive multi-variable approach for evaluating the feasibility of the model.•Aspen HYSYS software is used for simulation as well as sensitivity study.•Exergy efficiency and CO2 footprint are 32.03% and 0.2196 kgCO2/kWh.•Total unit cost of products and net present value are 89.81 $/GJ and $686,221,616
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This paper aims to improve car body stability performance by optimising locomotive parameters when coupler jack-knifing occurs during braking. In order to prevent car body instability behaviour ...caused by coupler jack-knifing, a multi-locomotive simulation model and a series of field braking tests are developed to analyse the influence of the secondary suspension and the secondary lateral stopper on the car body stability performance during braking. According to simulation and test results, increasing secondary lateral stiffness contributes to limit car body yaw angle during braking. However, it seriously affects the dynamic performance of the locomotive. For the secondary lateral stopper, its lateral stiffness and free clearance have a significant influence on improving the car body stability capacity, and have less effect on the dynamic performance of the locomotive. An optimised measure was proposed and adopted on the test locomotive. For the optimised locomotive, the lateral stiffness of secondary lateral stopper is increased to 7875 kN/m, while its free clearance is decreased to 10 mm. The optimised locomotive has excellent dynamic and safety performance. Comparing with the original locomotive, the maximum car body yaw angle and coupler rotation angle of the optimised locomotive were reduced by 59.25% and 53.19%, respectively, according to the practical application. The maximum derailment coefficient was 0.32, and the maximum wheelset lateral force was 39.5 kN. Hence, reasonable parameters of secondary lateral stopper can improve the car body stability capacity and the running safety of the heavy haul locomotive.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
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