Fuzzy PID Speed Control of Two Phase Ultrasonic Motor

Because of ultrasonicmotor’s time-variable nonlinearity, a online adaptive correction of PID controlparameters based on fuzzy logic is presented. The special nature of ultrasonicmotor’s speed control are fully taken into account in designing fuzzy rules.The amplitude of driving voltage is used as the control parameter to realizethe control method. The experiments indicate that the control characteristicsare much better than that of PID controller

The Economic Influence of Energy Storage Construction in the Context of New Power Systems

The increase in the proportion of renewable energy in a new power system requires supporting the construction of energy storage to provide support for a safe and stable power supply. In this paper, the computable general equilibrium (CGE) quantitative assessment model is used coupled with a carbon emission module to comprehensively analyze the benefits and costs of energy storage construction from a macro perspective. Taking Zhejiang Province as an example, the investment in and construction of energy storage under the new power system of the 14th Five-Year Plan will slow down the economic growth of Zhejiang Province to a slight extent, but this investment and construction can improve the income level of residents and further redistribute the income structure. At the same time, energy storage investment and construction are conducive to building a clean, low-carbon, and efficient power system. The construction of energy storage can smooth out changes in electricity demand, while enhancing the electricity consumption of the residential sector, making the core sector’s electricity consumption more efficient. In addition, the construction of energy storage in the new power system has a positive effect on carbon emission reduction in Zhejiang Province, with the CO2 growth rate being significantly lower than the baseline scenario

Numerical Investigation on Coal Combustion in Ultralow CO2 Blast Furnace: Effect of Oxygen Temperature

The cooling effect of room-temperature oxygen in oxygen blast furnaces with top gas recycling (TGR-OBF) delays the coal combustion process. To further explore the oxygen–coal combustion mechanism and intensify coal combustion in TGR-OBF, the effect of oxygen temperature on coal combustion was investigated using computational fluid dynamics (CFD). A three-dimensional model was developed to simulate the lance–blowpipe–tuyere–raceway of TGR-OBF. The effect of oxygen temperature at the same oxygen velocity and mass flow on coal combustion was investigated. Results showed the cooling effect of room-temperature oxygen was weakened, and the coal burnout was greatly increased with the increase in oxygen temperature. In particular, the coal burnout increased from 21.64% to 81.98% at the same oxygen velocity when the oxygen temperature increased from 300 to 500 K. The results provide useful reference for the development of TGR-OBF and coal combustion technology

Combustion Enhancement of Pulverized Coal with Targeted Oxygen-Enrichment in an Ironmaking Blast Furnace

In this study, a targeted oxygen-enrichment technology was proposed to enhance coal combustion in an ironmaking blast furnace. The coal flow and combustion characteristics under targeted oxygen-enrichment were investigated using the computational fluid dynamics (CFD) method. The results showed that oxygen utilization and coal burnout were significantly increased under targeted oxygen-enrichment. The coal burnout at 24% O2 concentration was 86.29%, which was the maximum and indicated an increase of 13.13%. However, the cooling effect of room-temperature oxygen had some adverse effects on coal combustion. Given this, the effect of coal particle temperature on coal combustion was investigated based on targeted oxygen-enrichment. The coal combustion process was further enhanced. The coal burnout at a 600 K particle temperature and 25% oxygen concentration was 91.12% and had an increase of 17.96%, which was the maximum

Simulation and Analysis of Land-Use Change Based on the PLUS Model in the Fuxian Lake Basin (Yunnan–Guizhou Plateau, China)

It is essential to study the characteristics of land use change in the Fuxian Lake basin, a plateau lake in Yunnan Province, and to predict the basin’s future trend of land use change for sustaining the key carriers of current national major strategies such as ecological civilization, green development, and rural revitalization. This study used the Fuxian Lake basin as the subject and based on the seven periods of historical land use data, added six driving factors including human and natural factors, applied patches to generate the land-use simulation model (PLUS), and forecasted and analyzed the characteristics of land-use change in the basin in 2048 under the three scenarios of natural trend development, ecological protection, and production protection. The results showed that: (1) the overall simulation accuracy of the model was 79.14%, Kappa index was 0.73, FOM value was 0.29, and the model’s consistency was high. The model can be used to simulate future land-use changes in the Fuxian Lake basin. (2) In the natural development scenario, land-use development and the driving factors in the basin have the following relationship: rainfall and trunk road distance significantly impacted the types of land that emphasize ecological conservation and product development. Elevation and soil distribution characteristics had a significant impact on land types focused mainly on water zones and ecological protection. The land types mainly focused on urban construction were greatly affected by elevation, trunk road distance, GDP per capita, and other factors. (3) The main direction of land-use change in the watershed is the mutual conversion between farmland and forest land, with the continuous expansion of construction land. In the production protection scenario, the area of farmland increased by 44.79 hm2. In the ecological protection scenario, the area of arbor forest land increased by 37.85 hm2 and the area of shrub forest land decreased by 62.37 hm2. (4) From the perspective of spatial distribution patterns, the regional hotspot change blocks are mainly concentrated in the north of the basin, along the coast of the north of Fuxian Lake, and the southern land. In general, the PLUS model had good applicability in this study. The simulation results of the different scenarios were in line with the land development in the Fuxian Lake basin and can provide scientific reference for land-space planning, ecological and production land constraints, and coordination of development in the Fuxian Lake basin

Analysis of Landscape Pattern Evolution and Driving Forces Based on Land-Use Changes: A Case Study of Yilong Lake Watershed on Yunnan-Guizhou Plateau

In order to explore the landscape pattern evolution and driving forces of the Yilong Lake watershed, the combined method of supervised classification with manual visual interpretation based on the landsat5TM/8OLI remote sensing image data sources was used to establish a high-precision spatial distribution information database of the Yilong Lake watershed. Landscape index was used to analyze the distribution and spatial pattern change characteristics of various land-use types. Based on correlation and principal component analysis, we discuss the relationship between the change characteristics of land-use type, distribution and spatial pattern, and the interference of local socio-economic development and natural factors. The results show that: (1) In the past 30 years, the land-use types of the Yilong Lake watershed are mainly forest, garden plot and cultivated land. The forest area decreased significantly by 30.45 km2, of which the fastest reduction stage was from 2000 to 2005, with a total reduction of 20.56 km2. The garden plot conversion is relatively large, with a total of 181.69 km2 transferred out, of which 28.84 km2 has become unused land, respectively. (2) In the past 30 years, the maximum patch index decreased by 9.94% and the patch density index increased by 14.25%, indicating that the landscape fragmentation in the whole basin increased. The Shannon diversity index showed an increasing process; the aggregation index showed a decreasing process. (3) The change in landscape pattern in the watershedwas closely related to economic growth, population growth, social affluence and agricultural development. Natural factors, social factors and economic indicators are significantly positively correlated with patch density, edge density, landscape shape index and Shannon diversity index, and significantly negatively correlated with the largest patch index and the contagion index. On the whole, the wetlands in the basin are shrinking and the landscape diversity is changing. Reducing the excessive impact of human activities on the watershed ecosystem is a key factor for the local protection of wetland resources and the maintenance of wetland ecological functions

Comparison of pulmonary function during interscalene block vs. supraclavicular block: a single-center, double-blind, randomized trial

Abstract Backround The supraclavicular plexus block (SCB) and interscalene plexus block (ISB) have the potential to pulmonary function, the duration of the potential remains uncertain. So, we compared the effect of SCB and ISB on pulmonary function, especially the duration time. Methods Ninety-six patients were finally allocated to group I and group S. The ISB and the SCB procedures were performed with ultrasound guidance before anesthesia induction. An investigator recorded the diaphragm mobility and respiratory function test indicators before the block (T0) and at 30 min (T30 min), 4 h (T4), 8 h (T8), and 12 h (T12) after the block. The diaphragmatic paralysis rate was calculated for above timepoint. The VAS, the recovery time for the sensory and motor block, and adverse reactions within 24 h of administering the block were also recorded. Results The recovery times of diaphragm mobility in group I were longer than those in group S. Compared with group I, group S had a significantly lower diaphragmatic paralysis rate during eupnea breathing at T30 min and T8 after the block. Similarly, group S had a significantly lower diaphragmatic paralysis rate at deep breathing at T30 min, T8, and T12 after the block. The recovery times of FEV1 and FVC in group I were longer than those in group S. The other results were not statistically significant. Conclusions Ultrasound-guided ISB resulted in a longer periods with a suppressive effect on pulmonary function than SCB. Trials registration 17/12/2019, ChiCTR1900028286