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Assessing the impact of photovoltaic power plants on carbon sequestration by regional vegetation is crucial for the scientific planning of clean energy initiatives. However, due to the extensive distribution and complex environments surrounding photovoltaic power stations, it is significant challenges that quantifying their impact in Guizhou Province using local field monitoring data, This study focuses on Guizhou Province and its photovoltaic power stations, examining changes in carbon sequestration from 2010 to 2022. By integrating remote sensing interpretation data related to photovoltaic installations, this research quantifies the emission reduction benefits associated with these power plants and determines the proportion of carbon sequestration attributable to vegetation affected by photovoltaic construction within overall emissions reductions. The findings reveal that: (1) The net primary productivity (NPP) across Guizhou Province exhibited an upward trend, with a notable increase observed in the western region while a localized decrease occurred in the eastern part; (2) The influence radius of photovoltaic power stations on vegetation carbon sequestration extends approximately 1500 m; however, over time this range has diminished to around 1000 m; (3) During 2010 to 2022, vegetation carbon sequestration impacted by photovoltaic development accounted for 8.39% per annum of total carbon emission reductions from solar energy generation, with a similar proportion noted for carbon dioxide emissions. By 2022, this percentage had decreased significantly to just 1.42%. This study provide a reference into accurately evaluating the emission reduction benefits conferred by photovoltaic power plants.

The traditional method of hydrology and water conservancy calculation is based on the assumption of natural runoff, while the applicability of method has weakened in the urbanization-affected river basins. The paper carried out research on hydrological calculation model of flood control in the middle and lower reaches of the Chuhe River under the background of urbanization. On the basis of the analysis of flood characteristics in river basins, the hydrological calculation model framework of flood control in the middle and lower reaches of the Chuhe River is constructed, which includes five modules: design rainstorm calculation, runoff calculation, regional flow concentration calculation, river-network confluence calculation and lake-reservoir regulation calculation. The parameters of runoff generation, overland flow concentration, hilly area flow concentration and river-network confluence are determined. Process simulation of the flood water levels and discharges in the middle and lower reaches of the Chuhe River in 1991 and 2008, which are the years with heavy rains, is conducted. The flood simulation of June 1991 shows that the error of water level is -1cm ~ + 8cm, and the error of discharge is +26 m3/s. The flood simulation of August 2008 shows that the error of water level is -8cm ~ + 2cm, and the error of discharge is -9 m3/s. The overall simulation results are relatively stable with all the calculation errors within the allowable range, and the results fit the facts well.

To improve the anti-disturbance ability of LCL grid-connected inverter system, a novel immersion and invariance based on active disturbance rejection control(I&I-ADRC) scheme is proposed in this paper. First, the target system with stronger anti-disturbance ability is immersed into the ADRC standard model by using the target system mapping method of immersion and invariance control. Then, the disturbance estimated by extended state observer (ESO) is compensated, and the immersion and invariance(I&I) control law is adopted to design the state error feedback（SEF）control law, thus I&I-ADRC is built, which has improved anti-disturbance ability and dynamic response performance. The stability of grid-connected inverter system is proved by Lyapunov theory. Simulation results show that the proposed strategy can effectively suppress the disturbance and has better tracking performance.

According to the non-linear and non-stationary characteristics of the vibration signal in the roller grinding manufacturing process, the background signals, namely the vibration signal when the grinder is idling and the vibration signal during contact grinding, are collected separately, and the signal is decomposed into multiple by the method of CEEMDAN modal decomposition. Then several components are removed by correlation analysis. Finally, the signal is denoised and analyzed by wavelet threshold denoising, which lays the foundation for the digital and intelligent grinding of diamond rollers by curve grinders. The results show that most of the grinding noise is in the low frequency, which is mainly caused by the internal friction of the machine tool; the frequency of the grinding vibration signal is mainly distributed around the two frequencies of 250hz and 350hz.

In micro electrical discharge machining (micro-EDM), polarity effect is attributed to the difference in energy distribution into the anode and cathode. Understanding the effect of machining polarity on energy distribution bears significance in predicting and controlling machining performances. Single discharge experiments were conducted in this study, to explore single discharge characteristics. The plasma radius and energy distribution were calculated by combining the crater size and the electro-thermal model. The results show that the influence of discharge current on crater depth-to-diameter ratio (H/D) is not significant with positive polarity. The plasma radius, fraction of energy transferred to workpiece, and crater size are greater for micro-EDM with negative polarity than positive polarity.

This paper conducts an in-depth study on the catering recommendation space based on different situations. By consulting the literature, visiting relevant experts, condensing the theoretical knowledge of TCM (Traditional Chinese Medicine) constitutional dietotherapy theory, it has extracted some key factors that can be effectively utilized in catering theory. The variable framework of the situational catering recommendation system is preliminarily constructed. Also, it has designed a mixed catering recommendation space that combines TCM Constitutional Theory and user situation, which not only meets individual preferences but also improves the users’ sub-health status. Finally, through the questionnaire survey, the importance of each attribute in the eyes of consumers has been recognized; then this essay provides a guidance for the recommendation ranking method in the design of the catering recommendation system after making the cross-analysis.

It analyses the composition and principle of high-sensitive wide-band magnetic-feedback inductive magnetic sensor to fulfil the demand of high-sensitive wide-band magnetic sensor in geological exploration. It studies main factors to the performance of wide-band magnetic sensor, such as turns of coils, core material features, and amplifier noise, specifies section-wise coil winding, the type and dimension of core material, and designs low-noise high-impedance LF chopping amplifier channel and composite amplifier with HF amplifier channel. The noise of magnetic sensor at 1 Hz is better than 10-4nT/Hz1/2, at 100Hz-1kHz band the noise floor is close to SQUID which can reach 10-6nT/Hz1/2. The magnetic sensor works at wide frequency band (0.0001Hz-10kHz) and ultra-low noise, which can meet the requirements of both AMT and CSAMT.

The red elemental selenoprotein was biosynthesized by active dry yeast in this study. Through a single factor experiment and L9(34)-orthogonal test fermentation condition optimization, the selenium content was 15.72 mg/g under optimal condition. The optimum culture condition was as follows: the sodium selenite concentration (0.8 mg/mL), culture time (36 h), the yeast dosage (5 g), pH (5.5), culture temperature (30°C), and the medium Baume degree (8 °Bé). The analysis of amino acid species, content and morphology of the product showed that the red elemental selenoprotein was successfully synthesized.

A series of La1-xCexNiO3 photocatalysts with different content of cerium element have been synthesized by sol-gel method. The as-prepared products were characterized by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The photocatalytic activities of these La1-xCexNiO3 composites under visible-light irradiation were evaluated by the degradation of methyl orange (MO). The effect of important operational parameters such as catalyst amount, reaction temperature, irradiation time, and comparison of photocatalytic activity with different dyes including methyl orange, alizarin red, alizarin yellow, xylenol orange were also studied. The results revealed that the La0.8Ce0.2NiO3 (LCNO) composites exhibited much higher photocatalytic activities than pure LaNiO3 (LNO).

The effect of board bending degree on hydrodynamic performances of a single-layer cambered otter-board was investigated using engineering models in a wind tunnel. Three different bending degree boards were evaluated at a wind speed of 28 m/s. Parameters measured included: drag coefficient Cx, lift coefficient Cy, pitch moment coefficient Cm, center of pressure coefficient Cp , over a range of angle of attack (0° to 70°). These coefficients were used in analyzing the differences in the performance among the three otter-board models. Results showed that the bending of the board(No. 2, No. 3) increased the water resistance of the otter-board, and improved the lift coefficient of the otter-board in the small angle of attack (0°

Ultra-high molecular weight polyethylene (UHMWPE) and graphene (GR) was melt compounded by reactive extrusion. Nanocomposite monofilaments were prepared by melt spinning through a co-rotating screw extruder and drawing at hot water. GR/UHMWPE nanocomposite ropes were twisted using nanocomposite monofilaments. A structure and mechanical properties of the GR/UHMWPE nanocomposite monofilaments and its ropes had been characterized by scanning electron microscopy (SEM), and mechanical test. Results showed that the monofilaments surface of monofilaments became rougher with introducing of GR nanosheets, which could be related to stacking of GR. The breaking load of GR/UHMWPE nanocomposite ropes was remarkably improved upon nanofiller addition, with the decrease of the elongation at break.

The water washing device for aerosol condensation is added in the pre-cleaning tower of ammonia desulfurization device, and the basic function of the water washing device for aerosol condensation system is through the use of air/mist dual fluid spray system, atomizing the water to produce a large number of droplets, and greatly increasing the contact probability with the fine aerosol in the flue gas, and thus improving the efficiency of desulfurization and dust removal. The industrial application verifies this water washing device for aerosol condensation can effectively control the aerosol pollution from exhausts of ammonia desulphurization, and realize the ultra-low flue gas emission.

As a driving aid system, automotive radar plays a more and more important role in reducing traffic accidents. In this paper, a simple and efficient automotive radar system based on MFSK (Multiple frequency shift keying) is designed, the system structure and implementation algorithm is presented. This system uses FPGA as the signal processing unit to ensure the response speed. In addition, the designed MFSK waveform algorithm achieved high precision and unambiguous measurement. The effectiveness of the system is verified by experiments and field measurements.

In this paper, a new type of 4PRR-P hybrid machining mechanism is presented. Based on the screw theory, the degree of freedom of the mechanism is verified. We solve the inverse position model of the the mechanism. The workspace of the mechanism is solved by the boundary search algorithm. The reasonable ranges of key scale parameters are obtained by investigating the influence of the parameters of the mechansm on its workspace. The above kinematic analyses and solving results can provide corresponding references for subsequent mechanism dynamics analysis and structural design.

Because planning management of the leisure and tourism-oriented suburban villages lags behind, a series of problems occur: sustainable development of rural tourism is limited, and the content of planning management is unclear, and implement does not reach the designed position. In order to solve these problems, through research and analysis, we master the status quo of planning management of leisure and tourism-oriented suburban villages in China, and determine the content of planning management. The author analyze the interactive relationship between system theory and leisure and tourism-oriented suburban rural planning management and construct a planning management system based on the perspective of systems theory. The informatization design of system was achieved by information technology. The results show that the informatization system based on the perspective of system theory not only provides a solution for the planning management of the leisure and tourism-oriented suburban villages, but also lays a foundation for software development and website function design.

The effect of panel shape on hydrodynamic performances of a vertical v-shaped double-slotted cambered otter-board was investigated using engineering models in a wind tunnel. Three different shape panels (rhomboid, left trapezoid and isosceles trapezoid) were evaluated at a wind speed of 28 m/s. Parameters measured included: drag coefficient Cx, lift coefficient Cy, pitch moment coefficient Cm, center of pressure coefficient Cp , over a range of angle of attack (0° to 70°). These coefficients were used in analyzing the differences in the performance among the three otter-board models. Results showed that the maximum lift coefficient Cy of the otter-board model with the isosceles trapezoid shape panels was highest (2.103 at α=45°). The maximum Cy/Cx of the otter-board with the rhomboid shape panels was highest (3.976 at α=15°). A comparative analysis of Cm and Cp showed that the stability of otter-board model with the isosceles trapezoid shape panels is better in pitch, and the stability of otter-board model with the left trapezoid shape panels is better in roll. The findings of this study can offer useful reference data for the structural optimization of otter-boards for trawling.

In this work, Numerical simulations based on finite element method have been carried out to study the effect of important process parameters on formability of AA5182 alloy sheets. The blank holder force between 0.5KN and 3KN and friction coefficient(μ) between 0.05 and 0.20, which resulted in successful drawing, was evaluated. Maximum percentage thinning has always been obtained at the conjunction of corner and bottom. The maximum thinning rate was nearly 20% for a maximum holder force of 3KN. Friction coefficient simulations are shown that as friction coefficient increasing, the thinning rate becomes larger and low friction coefficient is beneficial to the sheet forming.

With the intensified requirements on ambient air quality, controlling NOx emission from sintering flue gas has become the most important priority in steel industry. Ozone oxidation denitration process has become the most closely watched sintering flue gas denitration technology. In order to investigate the influence of different operating conditions on NO oxidation in practical engineering application of ozone oxidation denitration process, an ozone oxidation system was built, and sintering flue gas was extracted from the pipeline between the induced draft fan and the desulfurization tower. The influence of discharge power and O2 flow rate of ozone generator on O3 concentration, O3 yield and NO oxidation efficiency were investigated. The results indicated that NO oxidation efficiency increased with the discharge power. And the increase of O3 dosage imposed a significant influence on NO oxidation efficiency. However, little effect of O2 flow rate on NO oxidation efficiency was observed.

An accurate and timely forecast of medium and long-term runoff forecast is of great significance to reservoir safety and water resources scheduling. In order to improve the long-term runoff forecast accuracy of the reservoir, a long-term runoff forecasting model was constructed based on the principle of Mahalanobis distance discrimination analysis. The data sequence from 1952 to 2008 of Danjiangkou reservoir was selected, the correlation coefficient method and AIC criterion were used to sift out the highly correlated and independent factors, a long-term runoff forecasting model was constructed based on the principle of Mahalanobis distance discrimination analysis. The result showed that under the permutation error of 10%，the pass rate during the simulation period was 93.9%, and the pass rate during the inspection period was 87.5%. The research results serve as a reference for the operation of Danjiangkou reservoir.

Based on the present situation of water ecological civilization construction in Shenzhen, the paper summarizes the path of water ecological civilization construction with Shenzhen characteristics. That is to say, the construction is around the development vision of “river and sea are calm and peaceful, green mountains and clear water, modern livable, beautiful Pengcheng”, to create the eight major systems of water safety, water environment, water ecology, water conservation, water management, water landscape, water economy and water culture according to local conditions on the basis of the spatial layout of “nine basins and four sections, three bays and two belts, five-point and dual-core”. This construction mode provides an important reference for promoting the governance of Shenzhen water problems under the guidance of the concept of ecological civilization and provides a model reference for the construction of water ecological civilization in coastal cities[1,2,6].

Ozone oxidation denitration process has become the most closely watched sintering flue gas denitration technology currently. In order to investigate the influence of different operating conditions on NO oxidation in practical engineering application of this technology, an ozone oxidation system was built, and sintering flue gas was extracted from the pipeline between the induced draft fan and the desulfurization tower. The influence of flue gas flow and inlet NO concentration on NO oxidation was investigated by orthogonal experiments. The results indicated that NO oxidation efficiency increased with the O3 yield of ozone generator and O3 dosage under any flue gas conditions. Under the same inlet NO concentration, NO oxidation efficiency decreased with the increase of flue gas flow. Under the same flue gas flow and O3 dosage, with the increase of inlet NO concentration, the O3 utilization rate increased while the average oxidation energy consumption of each NO molecule decreased, which was beneficial to promote the NO oxidation efficiency. In practical engineering application, the setting of O3 dosage should take into account both engineering design indicators and economy. Ozone oxidation denitration process could achieve NO oxidation efficiency higher than 90% through reasonable design, indicating a good industrial application prospect in the treatment of sintering flue gas.

This paper presents some numerical simulation results of tensile properties of reinforcing bars spliced by grout-filled coupling sleeves under fire conditions to identify the effect of load ratio on fire resistance time of spliced reinforcing bars, which provide a useful base for predicting structural behaviors of pre-cast reinforced concrete buildings in fires. A spliced rebar system investigated in this paper consists of two equal-diameter steel reinforcing bars with 25mm diameter and a straight coupling sleeve with 50mm outer and 45mm inner diameters. As a result, the thickness of grout between steel bars and sleeves are 20mm. Firstly, the temperature distributions in steel bars connected by grout- filled coupling sleeves exposed to ISO 834 standard fire were calculated utilizing finite element analysis software ANSYS. Secondly, the stress changes in heated steel bars connected by grout-filled coupling sleeves under different constant tensile loads were calculated step by step until the rebar system failed due to fire. Thus, the fire resistant time of rebar spliced by grout-filled coupling sleeves under different axial tensile loads can be determined, further, the relationship between fire resistance time and axial tensile loads ratio can could be obtained. Finally, the fire resistant times versus axial tensile load ratios curve of grout-filled splice sleeve rebars exposed to ISO 834 standard fire is presented.

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The effect of deflector angle on hydrodynamic performances of a double-slotted cambered otter-board is investigated using engineering models in a wind tunnel. Three different angle combinations (35°-30°, 30°-25°and 25°-20°) are evaluated at a wind speed of 28 m/s. Parameters measured included: drag coefficient Cx, lift coefficient Cy, pitch moment coefficient Cm, center of pressure coefficient Cp, over a range of angle of attack (0° to 70°). These coefficients are used in analyzing the differences in the performance among the three otter-board models. Results shows that the maximum lift coefficient Cy of the otter-board model with the angle combination (35°-30°) of two deflectors is the highest (2.160 at a=55°). The maximum Cy/Cx of the otter-board with the angle combination (25°-20°) is the highest (3.842 at a=2.5°). A comparative analysis of Cm and Cp shows that the stability of otter-board model with the angle combination (25°-20°) is better in pitch, and the stability of otter-board model with the angle combination (30°-25°) is better in roll. The findings of this study can offer useful reference data for the structural optimization of otter-boards for trawling.

The effect of bevel angle of three-layer parallel plate of otter-board on hydrodynamic performances is investigated by model wind tunnel test. Four otter-board models are designed with four different bevel angles (8°, 10°, 12° and 14°) , and tested under the wind speed 28 m / s in wind tunnel. Model experiment is conducted to obtain the drag coefficients Cx, the lift coefficient Cy, the pitch moment coefficient Cm, the center of pressure coefficient Cp and calculated the lift-drag ratio Cy/Cx. The result shows that the maximum lift coefficient and the maximum lift-drag ratio of the otter-board model with a bevel angle 12 degree is higher, there is 2.598(a=65°) and 2.607(a=37.5°); For comparison in stability of otter-board, the stability of the otter-board model with the bevel angle 8 degree is better by the comparative analysis of Cm and Cp, the absolute value of Cm is 0.174 and the minimum variation coefficient of Cp is 4.37%. The results can offer reference for the structural optimization design of trawl otter-board.

Low-speed crawling phenomenon may occur when space manipulators run at a low speed, which may bring big problem for manipulation work. A kind of low-speed optimization algorithm based on gradient projection method is pro-posed in this paper. The designing of continuous balanced proportional factor can effectively reduce the quantitative differences between the homogeneous solution and the special solution, avoiding the joint velocities oscillations. The low-speed crawling problem can be effectively improved by appropriate increase of joint velocities. And the effectiveness and correctness of the optimization algorithm are confirmed by the simulation.