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Longitudinal ordinary rebars are discontinuous at the joints of precast concrete segmental bridges (PCSBs), which can open under tensile stresses induced by bending moments. This will lead to durability issues with the joints. To improve the bending properties of PCSBs, a novel joint type featuring continuous rebars was proposed in the present study. Three specimens were subjected to testing to examine the bending behavior of PCSBs using this new joint design compared to traditional joints. The crack propagation, structural deformation, joint opening width, strain in rebars, failure mode, stiffness, and flexural capacity were comprehensively investigated. The test results reveal that the continuous rebars effectively transferred bending normal stress between joints, ensuring full development of cracks in each beam segment. Effective control of joint opening width was also observed. Compared to traditional joints, the new joints exhibited a 29% to 33% increase in cracking load and a 32% increase in ultimate load. Failure in the continuous rebar joints was characterized by partial anchorage failure of the rebars along with localized concrete crushing in the top compression zone. Based on the test results, a computational method was proposed for calculating the cracking strength and flexural capacity of the new joints.

Nitrogen (N) application rates and planting density are key factors affecting grain yield and quality. In this experiment, four varieties, Huijing 753 (HJ 753), Huijing 855 (HJ 855), Huijing 866 (HJ 866), and Dangjing 8 (DJ 8), were used to investigate their effects on the yield and quality of japonica rice in Anhui, which has a lower soil N supply capacity. The current study set four levels of N application N1, N2, N3, and N4 (120, 180, 240, and 300) kg ha−1 and three planting densities D1, D2, and D3 (high-density: 45 × 104; medium-density: 37.5 × 104; low-density: 32.2 × 104) hills ha−1 for a total of 12 treatments. The effects of N application and planting density on rice yield, composition, processing quality, appearance quality, and cooking quality were analyzed. The results showed that with the increase in N application rates and planting density, the effective panicle number per plant and grain number per panicle of each rice variety increased, while HJ 753, HJ 855, and HJ 866 reached the highest yield under the N3D1 treatment and then gradually declined, and DJ 8 had the highest yield in the N4D1 treatment. In addition, the processing quality of various varieties can be improved by increasing the N application rate and planting density, but the appearance quality will deteriorate, the amylose content will also decrease, and gel consistency will also be lower. Therefore, under medium-planting density conditions, N at a rate of 240 kg ha−1 was the best for HJ 753, HJ 855, and HJ 866, and using 300 kg ha−1 for DJ 8 resulted in high grain yields and superior rice grain quality. In the next step, physiological, biochemical, and genotypic analyses of these three japonica rice varieties were carried out to provide a scientific basis and technical support for accelerating the breeding of high-yield japonica rice varieties.

The distribution of damage zones around a fault has long been regarded as a frontier and hot spot in the field of geoscience but is still not fully understood. In this study, we conducted field investigations and tests around the Xianshuihe fault zone (XSHF), a left-lateral strike-slip fault with a length of about 400 km located in the eastern margin of the Tibetan Plateau. The results reveal that the fracture frequency and rock strength parameters present a spatially asymmetric distribution along the fault and have a negative power-law correlation with the distance from the fault. The widths of the damage zones are approximately 20.8 km and 17.1 km in the southwest and northeast directions, respectively. Combined with the previous studies, we presented a negative power-law function to depict the correlation between slip displacement and the width of the damage zone and found that the growth rate of damage zone in faults with low displacement is greater than that in those with large displacement. The study demonstrates that the asymmetric distribution of the damage zone surrounding the XSHF is mainly due to the stress redistribution in different damage zones stemming from the left echelon and different activity rates of the blocks on both sides of the XSHF.

With the advancement of sensor technology, distributed processing technology, and wireless communication, Visual Sensor Networks (VSNs) are widely used. However, VSNs also have flaws such as poor data synchronization, limited node resources, and complicated node management. Thus, this paper proposes a sensor placement optimization method to save network resources and facilitate management. First, some necessary models are established, including the sensor model, the space model, the coverage model, and the reconstruction error model, and a dimensionality reduction search method is proposed. Next, following the creation of a multi-objective optimization function to balance reconstruction error and coverage, a clever optimization algorithm that combines the benefits of Genetic Algorithms (GA) and Particle Swarm Optimization (PSO) is applied. Finally, comparison studies validate the methodology presented in this paper, and the combined algorithm can enhance optimization effect while relatively reducing running time. In addition, a sensor coverage method for large-range target space with obstacles is discussed.

The mechanical strength of rice culm, an essential factor for lodging resistance and yield maintenance, is influenced by the composition and structure of the cell wall. In this study, we characterized a rice brittle culm mutant 22 (bc22), derived from LR005 through ethyl methanesulfonate (EMS) mutagenesis. The bc22 culm exhibited increased fragility and reduced mechanical strength compared to LR005. The mutant displayed pleiotropic effects, including a shorter plant height and panicle length, a smaller grain size, and the absence of the glume hairs. Scanning electron microscopy revealed a decrease in cell density and a looser structure in the bc22 culms. Biochemical analysis demonstrated a significant increase in hemicellulose content and a marked reduction in lignin content in the culm of bc22. Genetic analysis indicated that the brittle culm trait was governed by a single recessive gene. After employing bulked segregant analysis (BSA), whole-genome resequencing, and MutMap methods, LOC_Os02g25230 was identified as the candidate gene responsible for bc22. In bc22, a point mutation from proline (Pro) to leucine (Leu) in its coding region led to the pleiotropic phenotype. A complementation test further confirmed that the missense mutation causing the proline to leucine amino acid substitution in LOC_Os02g25230 was causative of the observed bc22 phenotype. Additionally, gene expression analysis showed that BC22 had higher expression levels in the culms, leaves, and spikelets compared to the roots. Taken together, our findings indicate that BC22 is a pleiotropic gene, and the influence of BC22 on brittleness may be associated with cell wall biosynthesis in rice culm.

The recycling and utilization of waste alkaline zinc manganese batteries (S-AZMB) has always been a focus of attention in the fields of environment and energy. However, current research mostly focuses on the recycling of purified materials, while neglecting the direct reuse of waste batteries. Here, we propose a new concept of preparing thermal catalysts by combining unpurified S-AZMB with CeO2 by means of ball milling. A series of characterizations and experiments have confirmed that the combination with S-AZMB not only enhances the thermal catalytic activity of CeO2 but also significantly enhances the concentration of surface oxygen vacancies. In the toluene removal experiment, the temperature (T90) at 90% toluene conversions of CeO2@S-AZMB was 180 °C, lower than the 220 °C for CeO2. More noteworthy is that this S-AZMB-based thermal catalyst can maintain a good structure and thermal catalytic stability in cyclic catalysis.

Thousand-grain weight is the main parameter for accurately estimating rice yields, and it is an important indicator for variety breeding and cultivation management. The accurate detection and counting of rice grains is an important prerequisite for thousand-grain weight measurements. However, because rice grains are small targets with high overall similarity and different degrees of adhesion, there are still considerable challenges preventing the accurate detection and counting of rice grains during thousand-grain weight measurements. A deep learning model based on a transformer encoder and coordinate attention module was, therefore, designed for detecting and counting rice grains, and named TCLE-YOLO in which YOLOv5 was used as the backbone network. Specifically, to improve the feature representation of the model for small target regions, a coordinate attention (CA) module was introduced into the backbone module of YOLOv5. In addition, another detection head for small targets was designed based on a low-level, high-resolution feature map, and the transformer encoder was applied to the neck module to expand the receptive field of the network and enhance the extraction of key feature of detected targets. This enabled our additional detection head to be more sensitive to rice grains, especially heavily adhesive grains. Finally, EIoU loss was used to further improve accuracy. The experimental results show that, when applied to the self-built rice grain dataset, the precision, recall, and mAP@0.5 of the TCLE–YOLO model were 99.20%, 99.10%, and 99.20%, respectively. Compared with several state-of-the-art models, the proposed TCLE–YOLO model achieves better detection performance. In summary, the rice grain detection method built in this study is suitable for rice grain recognition and counting, and it can provide guidance for accurate thousand-grain weight measurements and the effective evaluation of rice breeding.

In response to the challenges of long crossing distances and difficult site selection for linear engineering projects in mountainous areas, this article proposes a multi-scale engineering geological zoning (EGZ) method. This method is based on the linear engineering construction stage and transitions from regional EGZ to EGZ of key sections (areas with poor or worst engineering geological conditions). This method not only ensures the effect of EGZ but also reduces the workload. When carrying out the EGZ of key sections, the assessment ideas of geological disaster hazards were taken into consideration. An improved method for calculating the time probability and magnitude probability of disaster occurrence is proposed. Taking the National Highway 318 Chengdu-Shigatse section as an example, EGZ was carried out. Its results revealed that the Nyingchi section was the key section with poor and worst engineering geological conditions. EGZ of the key section showed that the areas with poor and worst engineering geological conditions were mainly distributed in the curved sections on the northern side of the linear project. The proposed method in this article provides guidance for EGZ for linear engineering projects in mountainous areas.

It is well-established that the honeycomb sandwich composite structures are easily prone to damage under low-energy impact. Consequently, it would lead to a dramatic decrease in structural load-bearing capacity and a threat to overall safety. Both experimental and numerical simulations are carried out to investigate the impact damage behavior of honeycomb sandwich composite specimens. The damage mode, damage parameters, and contact force-time curves of three types of panel materials with T300, T700, and T800 are obtained under different impact energies of 10 J, 20 J, and 40 J by the drop-weight impact experiment. Moreover, digital image correlation (DIC) tests are used to measure the deformation and strain of the lower panel. The experimental results reveal that the degree of damage increases with increasing impact energy. Particularly, the T300 panel specimen exhibits visible fiber fracture when subjected to an impact energy of 40 J. The impact process involves matrix cracking, fiber fracture, and delamination of the upper panel occurring first, followed by immediate crush damage to the honeycomb core and, finally, slight fiber damage to the lower panel. Due to its higher strength, the T800 panel specimen exhibits the highest damage resistance compared to the T700 and T300 panel specimens. To consider the microscopic failure criteria and various types of contact during the impact process, a finite element model of honeycomb sandwich composites is established, and numerical simulation analysis of low-energy impact is performed to determine the damage mode, damage size, and contact-force curves. Comparative analysis demonstrates good agreement between the simulation and experimental results. The findings of this study provide valuable technical support for the widespread application of honeycomb sandwich composites in the aviation field.

Potential rockfall source areas are widely distributed in the high mountain areas of the Tibetan Plateau, posing significant hazards to human lives, infrastructures, and lifeline facilities. In a combination of field investigation, high-precision aerial photogrammetry, and numerical simulation, we took the Maoyaba basin as an example to explore a rapid identification method for high-altitude rockfall sources. An automatic potential rockfall source identification (PRSI) procedure was introduced to simplify the process of rockfall source identification. The study revealed that rockfall sources are concentrated in areas with intense frost weathering. Our identification results were validated using rockfall inventory data detection from remote sensing images and field investigation. Of the rockfall source areas identified by the PRSI procedure, 80.85% overlapped with the remote sensing images result. The accuracy assessment using precision, recall, and F1 score was 0.91, 0.81, and 0.85, respectively, which validates the reliability and effectiveness of the PRSI procedure. Meanwhile, we compared the rockfall source distribution of five DEMs with different resolutions and four neighborhood areas. We discovered that, in addition to high-resolution DEMs (i.e., 1 m and 2 m), medium-resolution DEMs (i.e., 5 m, 12.5 m) also perform well in identifying rockfall sources. Finally, we conducted a hazard assessment based on Culmann’s two-dimensional slope stability model and rockfall hazard vector method. Appropriate protective measures should be taken at high-hazard sections to safeguard pedestrians, vehicles, and related infrastructure from rockfalls.

An important development in geometric algebra in recent years is the new system known as point geometry, which treats points as direct objects of operations and considerably simplifies the process of geometric reasoning. In this paper, we provide a complete formal description of the point geometry theory architecture and give a rigorous and reliable formal verification of the point geometry theory based on the theorem prover Coq. Simultaneously, a series of tactics are also designed to assist in the proof of geometric propositions. Based on the theoretical architecture and proof tactics, a universal and scalable interactive point geometry machine proof system, PointGeo, is built. In this system, any arbitrary point-geometry-solvable geometric statement may be proven, along with readable information about the solution’s procedure. Additionally, users may augment the rule base by adding trustworthy rules as needed for certain issues. The implementation of the system expands the library of Coq resources on geometric algebra, which will become a significant research foundation for the fields of geometric algebra, computer science, mathematics education, and other related fields.

The buckling failure of the afterburner cylinder is a serious safety concern for aero-engines. To tackle this issue, the buckling simulation analysis of the afterburner cylinder was carried out by using finite element method (FEM) software to obtain the buckling mode and critical buckling loads. It was found that the afterburner cylinder was susceptible to buckling when subjected to differential pressure or the compressive force of the rear flange. Buckling would occur when the differential pressure reached 0.4 times the atmospheric pressure or when the axial compressive force on the rear flange reached 222.8 kN. Buckling was also found at the front of the cylinder under the auxiliary mount load. Additionally, under various loads on the rear flange, buckling occurred in the rear section, with the buckling mode being closely related to the load characteristics. Based on the simulation results and structural design requirements, two structural improvements were proposed, including the wall-thickening scheme and the grid reinforcement scheme. FEM simulation analysis results showed that both schemes would improve the rigidity and stability of the afterburner cylinder. For the 0.3 mm increase in the wall thickness scheme, the critical buckling load increased by 17.86% to 66.4%; for the grid reinforcement scheme, the critical buckling load increased by 169% to 619%. Therefore, the grid reinforcement scheme had a stronger anti-buckling ability and was deemed the optimal solution. The findings of this paper could provide technical support for the structural design of large-sized and thin-walled components of aero-engines.

A highly regioselective reaction of 2-indolylmethanols with enamides has been developed at room temperature by using AlCl3 as a catalyst. A wide range of hybrids (40 examples) of indoles and enamides were obtained in moderate to good yields (up to 98% yield). This transformation represents the efficient way to introduce biologically important indoles and enamides skeleton into structurally complex hybrids.

Antiplatelet aggregation agents have demonstrated clinical benefits in the treatment of ischemic stroke. In our study, a series of novel nitric oxide (NO)-donating ligustrazine derivatives were designed and synthesized as antiplatelet aggregation agents. They were evaluated for the inhibitory effect on 5′-diphosphate (ADP)-induced and arachidonic acid (AA)-induced platelet aggregation in vitro. The results showed that compound 15d displayed the best activity in both ADP-induced and AA-induced assays, and compound 14a also showed quite better activity than ligustrazine. The preliminary structure-activity relationships of these novel NO-donating ligustrazine derivatives were discussed. Moreover, these compounds were docked with the thromboxane A2 receptor to study the structure-activity relationships. These results suggested that the novel NO-donating ligustrazine derivatives 14a and 15d deserve further study as potent antiplatelet aggregation agents.

Thermal spray deposition techniques have been well-established, owing to their flexibility in addressing degradation due to wear and corrosion issues faced due to extreme environmental conditions. With the adoption of these techniques, a broad spectrum of industries is experiencing continuous improvement in resolving these issues. To increase industrial-level implementation, state-of-the-art advanced materials are required. High-entropy alloys (HEAs) have recently gained considerable attention within the scientific community as advanced materials, mainly due to their exceptional properties and desirable microstructural features. Unlike traditional material systems, high-entropy alloys are composed of multi-component elements (at least five elements) with equimolar or nearly equimolar concentrations. This allows for a stable microstructure that is associated with high configurational entropy. This review article provides a critical assessment of different strengthening mechanisms observed in various high-entropy alloys developed by means of deposition techniques. The wear, corrosion, and oxidation responses of these alloys are reviewed in detail and correlated to microstructural and mechanical properties and behavior. In addition, the review focused on material design principles for developing next-generation HEAs that can significantly benefit the aerospace, marine, oil and gas, nuclear sector, etc. Despite having shown exceptional mechanical properties, the article describes the need to further evaluate the tribological behavior of these HEAs in order to show proof-of-concept perspectives for several industrial applications in extreme environments.

In this study, the static response of the preliminary pilot tunnels excavation to the ground, and the dynamic response of the group cavern system under seismic excitation under the use of the construction of a metro station based on the Pile-Beam-Arch approach are investigated through numerical calculation. The results suggest that the excavation sequences of “top first and then bottom” and “middle first and then both sides” can generate the minimum ground settlement. When the pilot tunnels were excavated, the horizontal PGA (peak ground acceleration) amplification coefficient tends to increase with significant nonlinear characteristics under the excitation of EI Centro wave with a horizontal acceleration of 0.15 g, and the horizontal PGA amplification coefficient reaches the maximum at the ground surface. The effect of horizontal acceleration around the upper pilot tunnels increases. Under the static load, the maximum principal stress of the lining structure after the completion of the pilot tunnels is largely concentrated at the foot of the arch of the pilot tunnel, and the maximum principal stress value is 1.124 MPa. The maximum principal stress is primarily concentrated at the foot of the arch and the foot of the upper and lower guide tunnel under seismic excitation, and the maximum principal stress value is 1.424 MPa. This study reveals that a reasonable excavation sequence can be employed when the pilot tunnels are being excavated to control the settlement. Furthermore, the support of the arch and footing of the pilot tunnels should be enhanced during the seismic design.

Due to soil disturbance during the construction of metro stations, the initial stress of the stratum is modified, leading to ground settlement within a particular range, fracturing the surrounding buildings and even causing significant ground deformation and building collapse. This paper employed the Pile-Beam-Arch method to assemble the Daguanying Station of Beijing Metro Line 7 as the engineering background. The numerical calculation method was used to study the regulations of ground settlement and structural deformation throughout the construction stage. Meanwhile, the effect of surface loading was taken into account and surface settlement control strategies were suggested. Finally, the Stochastic medium theory was used to predict surface settlement. It was evident from the study’s findings that the pilot tunnels excavation and the arches installation accounted for 67% and 23.1% of the total surface settlement, respectively, and produced the most surface settlement. Surface settlement can be significantly reduced by utilizing grouting reinforcement technology and the pilot tunnels excavation approach of “upper first, then lower and side first, then middle”. The structure was much less stressed during the pre-construction stage, with the maximum principal stress ranging from 1 to 5 MPa; after construction was finalized, the maximum principal stress reached 14.203 MPa, concentrating mostly in the middle column part, which was the consequence of the combined action of the upper load and the lower soil uplift. Additionally, there was a linear relationship between the surface load and ground settlement. The bottom slab and the middle column were situated where the structure’s most unfavorable components were concentrated. The conclusions of the surface settlement prediction demonstrated that there were discrepancies between the theoretical calculation and the simulated; thus, the prediction results were more conservative. The study results can serve as a reference for construction sites.

The largest Precambrian gasfield in China has been found from the Ediacaran (Sinian) carbonates in the central Sichuan Basin. The deep ancient reservoirs were generally attributed to the high-energy mound-shoal body in the carbonate platform. However, there is still little understanding on the distribution of the mound-shoal bodies that hampers further gas exploitation from the deep subsurface. Based on the seismic data, a large strike-slip fault system was identified by new 3D seismic data in the central Sichuan Basin. Further, it was found that the strike-slip fault had some effects on the mound-shoal bodies of the Ediacaran Dengying Formation. First, the platform margin was divided by strike-slip faults into three distinct segments to show two weak-rimmed margins and one interbedded rimmed margin. Second, the platform margin could be offset or migrated with the strike-slip faults. Third, there is varied margin thickness across the strike-slip fault zone. In the inner platform, more carbonate mound-shoal bodies developed behind the weak-rimmed margin that was divided by the strike-slip fault zones. In addition, the mound-shoal bodies may be separated by faulted sag. Further, the mound-shoal bodies may have developed along the faulted higher position in one side of the strike-slip fault zone. These patterns of the mound-shoal bodies suggest that the strike-slip fault had an important role in the sedimentary microfacies’ diversity in the intracratonic carbonates. The low displacement of the strike-slip fault is chiefly responsible for a weaker controlling effect on the microfacies change in the intracratonic basin rather than other tectonic settings.

To study stress field distributions during the construction of a group of tunnels using the pile–beam–arch method, the excavation for an underground station of Beijing subway line 7 was taken as an engineering problem, and a numerical structural model of a tunnel group was built with the aid of software. In this model, four stress-monitoring planes were set up to extract the data obtained from monitoring stress. The construction of the pilot tunnels was simulated according to six established construction schemes, and images were generated for the stress field distribution on each monitoring plane using different schemes. Finally, a verification of physical model tests was carried out. The results show that the effect of excavation on vertical stress in pilot tunnels has a range that is essentially equal to twice the width of the station. After the excavation of pilot tunnels, peaks appeared both at the tops of the pilot tunnels and between the bottoms of the tunnels; moreover, valleys appeared both at the bottoms of the pilot tunnels and between the tops of the tunnels. Pilot tunnels located at the top of the group were less affected during excavation than the tunnels located at the bottom of the group both in stress concentration factor and in the point of extreme stress. Finally, the model verified the numerical simulation results of the stress variation law.

Returning corn cobs to the field during corn kernel harvesting is an effective way to improve soil properties and increase crop yield. However, seasonally frozen soil seriously hinders the field decomposition process of corn cobs. To explore the decomposition characteristics and promote field decomposition, in this study, the nylon mesh bag method was used to perform field decomposition tests for 150 days. Fiber composition analysis and microstructure observation were carried out. The results showed that the field decomposition of corn cob was influenced by temperature, precipitation, and frozen soil environment. The 150-day cumulative decomposition rates of the pith, woody ring, and glume were 40.0%, 24.2%, and 36.3%, respectively. Caused by the difference in fiber compositions, the decomposition speeds of pith and glume were much higher than that of the woody ring. The complex microstructures of the pith, woody ring, and glume led to differences in the accessibility of cellulose, which indirectly influenced the field decomposition characteristics. The homogeneous sponge-like structure of the pith and glume increased the accessibility of cellulose and ultimately accelerated the field decomposition, while the compact lignocellulosic structure of the woody ring hindered the decomposition process. Compared with corn stalk, corn cob had similar or even better field decomposition characteristics and excellent application prospects.

A re-entry path planning method in omitting areas for service robots is suggested based on dynamic Inver-Over evolutionary algorithms after the robot automatically avoids obstacles. The complete coverage path planning is researched for cleaning service robots. Combined with features of dynamic travelling salesmen problem (DTSP), a local operator is employed for the path planning to enhance real-time dynamic properties of the Inver-Over algorithm. The method addresses the path planning problem that a number of cells undergo dynamic changes over time under work environment of cleaning robots. With simulations and experiments performed, it is discovered that the average relative error is 2.2% between the re-entry path planning and the best path, which validates the effectiveness and feasibility of the method.

In order to effectively evaluate shale gas reservoirs with low porosity, extra-low permeability, and no natural productivity, dipole array acoustic logging, which can provide various types of information including P-wave slowness (DTC) and S-wave slowness (DTS), is widely used. As the dipole array acoustic logging tool has a larger investigation depth and is suitable for complex borehole environments, such as those with a high wellbore temperature, high drilling fluid column pressure, or irregular borehole wall, it has been mainly applied to the evaluation of lithology, gas potential, fractures, and stimulation potential in shale gas reservoirs. The findings from a case study of the Sichuan Basin in China reveal that the acoustic slowness, S-P wave slowness ratio (RMSC), and S-wave anisotropy of the dipole array acoustic logging can be used to qualitatively identify reservoir lithology, gas potential, and fractures. Using the relationship between DTC and the total porosity of shale gas reservoirs, and combined with the compensated neutron (CNL) and shale content (Vsh) of the reservoir, a mathematical model for accurately calculating the total porosity of the shale gas reservoir can be established. By using the relationship between the RMSC and gas saturation in shale gas reservoirs and tied with density log (DEN), a mathematical model of gas saturation can be established, and the determination of gas saturation by the non-resistivity method can be achieved, delivering a solution to the issue that the electric model is not applicable under low resistivity conditions. The DTS, DTC, and DEN of shale can be used to calculate rock mechanic parameters such as the Poisson’s ratio (POIS) and Young’s modulus (YMOD), which can be used to evaluate the shale stimulation potential.

An interesting and challenging problem in mathematics is how to construct fair dice pairs. In this paper, by means of decomposing polynomials in a residue class ring and applying the Discrete Fourier Transformation, we present all the 2000 fair dice pairs and their 8 equivalence classes in a four-person game, identifying what we call the mandarin duck property of fair dice pairs.

In this study, a new permanent magnet rotary-linear (RotLin) motor is proposed for foldable photovoltaic units. Firstly, the mechanical structure, operation principles and magnetic circuits of the motor are introduced, and a design procedure elaborated the parameters calculation in the linear part and the rotary part. Finite element method (FEM) is used to analyze the magnetic field of the motor, and linear force outputs and torque outputs are obtained. Secondly, a control scheme is designed for the prototype of the motor including the position control and the speed control. The deformation on the mover and the magnetic coupling effect between the linear part and the rotational part are discussed. Finally, experimental results show that this motor can simultaneously realize a linear movement with continuous rotation. The linear poisoning accuracy can achieve 0.4 µm and the angular speed can be controlled with steady errors less than 3 rpm, proving the effectiveness of the proposed RotLin motor.

Isoprene has a potentially large effect on ozone (O3) formation in the subtropical, highly polluted city of Guangzhou. Online measurements of isoprene in Guangzhou city are scarce; thus, isoprene levels were monitored for one year at the Guangzhou Panyu Atmospheric Composition Station (GPACS), a suburban site in Guangzhou, using an online gas chromatography-flame ionization detector (GC–FID) system to investigate the characterization and reactivity of isoprene and its effect on the O3 peak profile in different seasons. The results showed that the daily average mixing ratios of isoprene at GPACS were 0.40, 2.20, 1.40, and 0.13 mixing ratio by volume (ppbv) in spring, summer, autumn, and winter, respectively. These values were considerably higher than the mixing ratios of isoprene in the numerous other subtropical and temperate cities around the world. Furthermore, isoprene ranked first with regard to O3 formation potential (OFP) and propylene-equivalent mixing ratio among 56 measured non–methane hydrocarbons (NMHCs). The ratios of isoprene to cis-2-butene, an exhaust tracer, were determined to estimate the fractions of biogenic and anthropogenic emissions. The results revealed a much greater contribution from biogenic than anthropogenic factors during the daytime in all four seasons. In addition, night-time isoprene emissions were mostly associated with vehicles in winter, and the residual isoprene that remained after photochemical loss during the daytime also persisted into the night. The high levels of isoprene in summer and autumn may cause the strong and broad peaks of the O3 profile because of its association with the most favorable meteorological conditions (e.g., high temperature and intense solar radiation) and the highest OH mixing ratio, which could affect human health by exposing people to a high O3 mixing ratio for prolonged periods. The lower mixing ratios of isoprene resulted in a weak and sharp peak in the O3 profile in both spring and winter. The high level of isoprene in the subtropical zone could accentuate its large impact on atmospheric oxidant capacity and air quality in Guangzhou city.

Reconciling competing desires to build urban models that can be simple and complicated is something of a grand challenge for urban simulation. It also prompts difficulties in many urban policy situations, such as urban sprawl, where simple, actionable ideas may need to be considered in the context of the messily complex and complicated urban processes and phenomena that work within cities. In this paper, we present a novel architecture for achieving both simple and complicated realizations of urban sprawl in simulation. Fine-scale simulations of sprawl geography are run using geographic automata to represent the geographical drivers of sprawl in intricate detail and over fine resolutions of space and time. We use Equation-Free computing to deploy population as a coarse observable of sprawl, which can be leveraged to run automata-based models as short-burst experiments within a meta-simulation framework.

In this paper, an effective low-speed oscillating wave power generator and its energy storage system have been proposed. A vertical flux-switching permanent magnet (PM) machine is designed as the generator while supercapacitors and batteries are used to store the energy. First, the overall power generation system is established and principles of the machine are introduced. Second, three modes are proposed for the energy storage system and sliding mode control (SMC) is employed to regulate the voltage of the direct current (DC) bus, observe the mechanical input, and feedback the status of the storage system. Finally, experiments with load and sinusoidal mechanical inputs are carried out to validate the effectiveness and stability of power generation for wave energy. The results show that the proposed power generation system can be employed in low-speed environment around 1 m/s to absorb random wave power, achieving over 60% power efficiency. The power generation approach can be used to capture wave energy in the future.

Time-of-Flight (ToF) cameras, a technology which has developed rapidly in recent years, are 3D imaging sensors providing a depth image as well as an amplitude image with a high frame rate. As a ToF camera is limited by the imaging conditions and external environment, its captured data are always subject to certain errors. This paper analyzes the influence of typical external distractions including material, color, distance, lighting, etc. on the depth error of ToF cameras. Our experiments indicated that factors such as lighting, color, material, and distance could cause different influences on the depth error of ToF cameras. However, since the forms of errors are uncertain, it’s difficult to summarize them in a unified law. To further improve the measurement accuracy, this paper proposes an error correction method based on Particle Filter-Support Vector Machine (PF-SVM). Moreover, the experiment results showed that this method can effectively reduce the depth error of ToF cameras to 4.6 mm within its full measurement range (0.5–5 m).