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In order to solve the problem of fluid accumulation in horizontal gas wells and improve the fluid-carrying capacity and recovery efficiency of gas wells, this paper simulates three internal vortex tools using the commercial software ANSYS FLUENT, and analyzes the drainage recovery efficiency of the three vortex structures and the vortex characteristics of the downstream section vortex field. The results show that the axial velocity of the three-bladed spiral tube in the cyclonic field rotates quasi-periodically with the flow field compared with the internal vortex tube and the rifled tube, and the axial velocity, tangential velocity and vortex intensity of the three-bladed vortex tube guided flow field are the highest; meanwhile, the axial velocity, tangential velocity and vortex intensity of the three-bladed spiral tube guided flow field decay the fastest, and the line rifled tube decays the slowest. The liquid phase in the cyclonic field exhibits obvious spiral motion and maintains a long-distance cyclonic flow state under the action of cyclonic flow. The enhancement of the vortex intensity easily leads to the increase of liquid volume fraction and liquid film thickness at the tube wall. Through the analysis of the energy efficiency of the three structures, it is found that the three-leaf spiral tube is more suitable for the initial phase of drainage transport, while the internal vortex tube is more favorable for the stable phase of transport. The study of the gas-liquid swirl flow of the three swirl tools demonstrated the feasibility of the internal swirl tool for application in horizontal wells. It can provide theoretical guidance and practical basis for effective liquid filling with internal vortex tools in the future.

The quality of wine grapes in dry climates greatly depends on utilizing optimal amounts of irrigation water during the growing season. Robust and accurate techniques are essential for assessing crop water status in grapevines so that both over-irrigation and excessive water deficits can be avoided. This study proposes a robust strategy to assess crop water status in grapevines. Experiments were performed on Riesling grapevines (Vitis vinfera L.) planted in rows oriented north–south and subjected to three irrigation regimes in a vineyard maintained at an experimental farm in southeastern Washington, USA. Thermal and red–green–blue (RGB) images were acquired during the growing season, using a thermal imaging sensor and digital camera installed on a ground-based platform such that both cameras were oriented orthogonally to the crop canopy. A custom-developed algorithm was created to automatically derive canopy temperature (Tc) and calculate crop water stress index (CWSI) from the acquired thermal-RGB images. The relationship between leaf water potential (Ψleaf) and CWSI was investigated. The results revealed that the proposed algorithm combining thermal and RGB images to determine CWSI can be used for assessing crop water status of grapevines. There was a correlation between CWSI and Ψleaf with an R-squared value of 0.67 for the measurements in the growing season. It was also found that CWSI from the shaded (east) side of the canopy achieved a better correlation with Ψleaf compared to that from the sunlit (west) side around solar noon. The created algorithm allowed real-time assessment of crop water status in commercial vineyards and may be used in decision support systems for grapevine irrigation management.

Tomato (Solanum lycopersicum) is a vital crop in China, yet its growth and quality are compromised by environmental stresses. This study investigated the role of myelocytomatosis (MYC) transcription factors (SlMYCs) in tomato stress tolerance. We identified 23 potential SlMYC genes and analyzed their physicochemical properties, evolutionary relationships, gene structures, conserved domains, expression profiles, interaction networks, promoter sequences, and 3D models using bioinformatics. Phylogenetic analysis classified the SlMYCs into three groups with similar structural characteristics. Protein interaction networks revealed significant connections between SlMYCs and proteins involved in drought, chilling, and salt tolerance, particularly emphasizing the jasmonic acid signaling pathway. Experimental treatments with methyl jasmonate (MeJA) and simulated stress conditions showed that several SlMYC genes were responsive to these stimuli, with SlMYC1 and SlMYC2 demonstrating consistent expression patterns across various tissues. Further network analyses and molecular docking studies indicated potential binding interactions for these two genes. The findings confirmed that SlMYC1 and SlMYC2 contributed to tomato’s abiotic stress tolerance, highlighting their potential for breeding programs aimed at improving stress resilience in tomato varieties. This research laid the groundwork for enhancing tomato varieties under environmental stressors.

Due to the complex shape of the tea tree canopy and the large undulation of a tea garden terrain, the quality of fresh tea leaves harvested by existing tea harvesting machines is poor. This study proposed a tea canopy surface profiling method based on 2D LiDAR perception and investigated the extraction and fitting methods of canopy point clouds. Meanwhile, a tea profiling harvester prototype was developed and field tests were conducted. The tea profiling harvesting device adopted a scheme of sectional arrangement of multiple groups of profiling tea harvesting units, and each unit sensed the height information of its own bottom canopy area through 2D LiDAR. A cross-platform communication network was established, enabling point cloud fitting of tea plant surfaces and accurate estimation of cutter profiling height through the RANSAC algorithm. Additionally, a sensing control system with multiple execution units was developed using rapid control prototype technology. The results of field tests showed that the bud leaf integrity rate was 84.64%, the impurity rate was 5.94%, the missing collection rate was 0.30%, and the missing harvesting rate was 0.68%. Furthermore, 89.57% of the harvested tea could be processed into commercial tea, with 88.34% consisting of young tea shoots with one bud and three leaves or fewer. All of these results demonstrated that the proposed device effectively meets the technical standards for machine-harvested tea and the requirements of standard tea processing techniques. Moreover, compared to other commercial tea harvesters, the proposed tea profiling harvesting device demonstrated improved performance in harvesting fresh tea leaves.

Automated technologies in precision agriculture enable unmanned systems to precisely target areas with chemicals through controlled nozzle movements. Quantitative assessment of these sprayers can enhance spraying strategies, catering to different canopy sizes, row spacing and coverage objectives. This research assessed an unmanned sprayer equipped with pan-tilt nozzles for targeted area control and spray coverage adjustment. The spray cloud path on the canopy, as the nozzles moved vertically and the sprayer advanced, was simulated mathematically. A model was developed to determine the swing angle based on orchard/vineyard geometrical parameters. This model was then applied in field tests in a vineyard and an apple orchard. Various nozzle-heading angles, driving speeds, and flow rates were experimented with, using average coverage and droplet density as the evaluation criterion. The findings showed that the developed model offered an effective method for determining the swing angles. Lowering driving speeds and increasing flow rates were found to notably enhance coverage. A 45º nozzle-heading angle proved more effective in vineyards, whereas a 90º angle yielded better results in apple orchards, reflecting the variations in canopy size and row spacing. The unmanned sprayer demonstrated great potential for autonomous spraying in vineyards and orchards.

Structure optimization is widely used in engineering today, it is very important to carry out the optimization after the preliminary design to reduce the weight of the structure. This paper is based on the basic theory of the finite element method. Firstly, the static analysis of flap track is carried out, the stress distribution and stiffness results are obtained. After that, a topology optimization is carried out based on the Hypermesh software. Lastly, a size optimization is carried out to get an easy processing structure. In conclusion: This paper studies the flap track, the optimization is carried out for flap track, the overall weight of the flap track is reduced by 15% under the satisfaction of safety and stiffness.

Transportation accessibility has been treated as an important means of reducing the urban-rural income disparity. However, only a few studies have examined the effects of different types of transportation accessibility on urban-rural income disparity and their spatial heterogeneity. Based on data from 285 prefecture-level (and above) Chinese cities in 2000, 2005, 2010, 2015, and 2020, this study uses spatial econometric models to examine how highway accessibility and railway accessibility influence the urban-rural income disparity and to identify their spatial heterogeneity. The result reveals that highway accessibility and railway accessibility have ‘coreperiphery’ ring-like circle structures. The urban-rural income disparity exhibits strong spatial clustering effects. Both highway accessibility and railway accessibility are negatively associated with urban-rural income disparity, and the former having a greater effect size. Moreover, there is a substitution effect between highway accessibility and railway accessibility in the whole sample. Furthermore, these associations differ in geographic regions. In the central region, highway accessibility is more important in reducing the urban-rural income disparity, but its effect is weakened with the increase of railway accessibility. In the western region, railway accessibility has a larger effect on narrowing the urban-rural income disparity, and this effect is strengthened by the increase of highway accessibility. We conclude that improving transportation accessibility is conducive to reducing the urban-rural income disparity but its effect is spatial heterogenetic. Highways and railways should be developed in a coordinated manner to promote an integrated transport network system.

A timely and appropriate level of water deficit is desirable in wine grape production to optimize fruit quality for winemaking. Regulated deficit irrigation (RDI) is an irrigation management strategy which applies less water than the full water requirement in some growing phases (e.g., from fruit set to veraison) to achieve a mild to moderate water stress. The implementation of RDI in wine grape production requires a combination of technical knowledge, accurate assessment and monitoring, and effective decision-making to achieve the desired balance between water stress and adequate water availability to the plants. This research aimed to develop and validate a comprehensive decision-support system for precision RDI management in vineyards. The proposed system was aimed to accurately assess the soil and plant water status through hyperspectral imaging (HSI). By doing so, the system sought to provide appropriate irrigation plans to achieve the desired soil water content threshold optimally.This research comprised three studies aimed at developing and validating several data-driven models as decision-support tools for precision deficit irrigation management in wine grapes. The first two studies focused on developing ground-based approaches to detect grapevine water status using HSI. The first study aimed to develop ground-based approaches for detecting soil and grapevine water status using HSI obtained in diffused lighting conditions. It was found that using spectral data obtained under diffused light resulted in improved model performance compared to using spectral data obtained under direct sunlight. This allowed for high-resolution sensing of grapevine water status by estimating leaf water potential and stomatal conductance. The second study fused HSI with 3D point clouds to address the effect of varied leaf orientations and enabled a Multiblock Partial Least Squares-based model to estimate leaf water potential with high accuracy. The third study aimed to develop a decision-support system for managing precision RDI in vineyards. The system consists of a soil moisture prediction model and an RDI scheduling model developed based on artificial neural networks. Validation tests showed that the soil moisture prediction model could predict the soil moisture in the following week with an R2 of 0.93 and RMSE of 0.86 %, and the RDI scheduling model could estimate the weekly irrigation water amount for maintaining a target soil moisture with an R2 of 0.94 and RMSE of 8.85 L per drip irrigation emitter. These studies contribute to developing efficient data-driven approaches to assess grapevine water status and optimize deficit irrigation plans for dynamic soil water threshold. The outcomes of this research could aid in achieving a balance between yield and fruit quality in wine grape production.

Transportation accessibility has been treated as an important means of reducing the urban-rural income disparity.However,only a few studies have examined the effects of different types of transportation accessibility on urban-rural income disparity and their spatial heterogeneity.Based on data from 285 prefecture-level(and above)Chinese cities in 2000,2005,2010,2015,and 2020,this study uses spatial econometric models to examine how highway accessibility and railway accessibility influence the urban-rural income disparity and to identify their spatial heterogeneity.The result reveals that highway accessibility and railway accessibility have'core-periphery'ring-like circle structures.The urban-rural income disparity exhibits strong spatial clustering effects.Both highway accessib-ility and railway accessibility are negatively associated with urban-rural income disparity,and the former having a greater effect size.Moreover,there is a substitution effect between highway accessibility and railway accessibility in the whole sample.Furthermore,these associations differ in geographic regions.In the central region,highway accessibility is more important in reducing the urban-rural in-come disparity,but its effect is weakened with the increase of railway accessibility.In the western region,railway accessibility has a lar-ger effect on narrowing the urban-rural income disparity,and this effect is strengthened by the increase of highway accessibility.We conclude that improving transportation accessibility is conducive to reducing the urban-rural income disparity but its effect is spatial het-erogenetic.Highways and railways should be developed in a coordinated manner to promote an integrated transport network system.

As Aarati Kanekar states in Architecture's Pretexts: Spaces of Translation, a book addressing the issues of construction, translation and transformation of meaning across media, “there is always an element of metamorphosis when meaning is translated between one symbolic form and another so that the body of the work undoubtedly becomes modified when perceived from different vantage points.”1 Literature and space can be not only two mediums complementing each other in forming a complete narrative, but also distinctive “reincarnations of the original” under new interpretations. With its root in the Latin verb “narrare,” a narrative is an organized sequence of real or fictional events recounted by the narrator. Spatial narrative, creating interpretations with the formal language of interior design, is a common tactic of the practice. By investigating the components of a textual narrative, one can translate the language of text into spatial language, and reveal new aspects or information that were unseen in the other medium. Spatial narrative takes the practice of interior design beyond satisfying the practical needs of its occupants, to engage and impact one’s psychological and physical behavior within the space. The experience of the space might not be collective but would create a connected series of moments that can be remembered and shared. The significance of the phenomenological space therefore exits within its poetic meaning in addition to its functionality. The study examines the relationship and translating process between textual and spatial narratives. Context, time, place, happenings, and character in a text can be opportunities for translation into instances interpreted through formal design elements, such as light, material, geometry, and programmatic requirements; these instances will become part of the totality of the architectural experience to create sequence and understanding. The resulted space could form a new vocabulary of reading spatial narratives, while also challenging the singular trajectory of a text. The project approaches this thesis question programmatically with a cemetery, where a narrative exists within the ritual of commemorating death (but no specific story has been provided). Dante’s Divine Comedy has been selected as the text to augment the narrative in which the discourse of life and death takes the form of an epic poem. While Dante’s poem has a heavy presence of Christianity, serving as a teaching of morality and piety, the space aims to serve beyond the framework of faiths and religions. Giuseppe Terragani’s Danteum, a conceptual project of poetic allegory taking the Comedy as its architectural program, provides an exemplar to test against. The selected site Glenwood Power Plant is an abandoned building near water and nature, its forgotten history and topographic location provide a crucial device in the project’s physicality and symbolic meaning. The design aims to create a journey for its occupants (alive and deceased), a space that resides between the boundaries of life and death, self and others, body and spirit, time and existence.