How to Develop the Rice Industry in Wuchang City?

The rice industry in Wuchang City has the advantages of improved varieties,well-known brands,technology management practices,and also the disadvantages of low coverage of farmer associations,single product variety,low level of deep processing and inefficient quality control.In this article,we analyze the current situation of the rice industry in Wuchang City,and point out some problems in the circulation system of Wuchang rice.Finally,we put forth the following recommendations:supporting the building of farmer associations and strengthening the farmers'bargaining power and status in the market;supporting the leading enterprises to develop many rice product varieties and improve the deep processing capacity;further improving the support service system.

Analysis on the Building of Chengdu's City Brand as“Three Cities and Three Capitals”-Taking Jiezi Ancient Town as an Example

"Three Cities and Three Capitals"is a city brand that Chengdu has been vigorously building.Based on the analysis of the brand construction background,the brand building of Jiezi Ancient Town,and the problems existing in the current brand building of Jiezi Ancient Town,this paper puts forward suggestions,including reconstruction of cultural resources,building an industrial framework,and giving full play to the role of market entities,so as to provide guidance for the cultivation of the brand characteristics in the ancient town and better shape the city brand of"Three Cities and Three Capitals"in Chengdu.

Modelling and applications of dissolution of rocks in geoengineering

The subsoil contains many evaporites such as limestone,gypsum,and salt.Such rocks are very sensitive to water.The deposit of evaporites raises questions because of their dissolution with time and the mechanical-geotechnical impact on the neighboring zone.Depending on the configuration of the site and the location of the rocks,the dissolution can lead to surface subsidence and,for instance,the formation of sinkholes and landslides.In this study,we present an approach that describes the dissolution process and its coupling with geotechnical engineering.In the first part we set the physico-mathematical framework,the hypothesis,and the limitations in which the dissolution process is stated.The physical interface between the fluid and the rock(porous)is represented by a diffuse interface of finite thickness.We briefly describe,in the framework of porous media,the steps needed to upscale the microscopic-scale(pore-scale)model to the macroscopic scale(Darcy scale).Although the constructed method has a large range of application,we will restrict it to saline and gypsum rocks.The second part is mainly devoted to the geotechnical consequences of the dissolution of gypsum material.We then analyze the effect of dissolution in the vicinity of a soil dam or slope and the partial dissolution of a gypsum pillar by a thin layer of water.These theoretical examples show the relevance and the potential of the approach in the general framework of geoengineering problems.

On 2D approximations for dissolution problems in Hele-Shaw cells

In this paper, we study the dissolution problems occurring in laterally large 3D systems with very small dimensions along the third coordinate, such as fractures or Hele-Shaw cells. On the basis of the scale separation assumption, we apply upscaling to the 3D pore-scale model using the volume averaging method to develop 2D averaged equations. The influence of the choice of momentum equations on the accuracy of the 2D Hele-Shaw model is discussed, and we show that the results obtained using Darcy-Brinkman equations are better than those obtained using Darcy’s law, because of the consideration of the viscous boundary layer. The validity and accuracy of the resulting 2D model are assessed based on comparisons with full 3D solutions for problems corresponding to the existence of geometrical 3D features to which a simple averaging procedure along a line(i.e., the height of the gap) perpendicular to the 2D plane cannot be applied, such as the dissolution of pillars. The results show that when Péclet and Reynolds numbers exceed certain limits, 3D effects must be considered. Moreover, natural convection effects are important when the Rayleigh number is large.

Joint specular highlight detection and removal in single images via Unet-Transformer

Specular highlight detection and removal is a fundamental problem in computer vision and image processing.In this paper,we present an efficient endto-end deep learning model for automatically detecting and removing specular highlights in a single image.In particular,an encoder–decoder network is utilized to detect specular highlights,and then a novel Unet-Transformer network performs highlight removal;we append transformer modules instead of feature maps in the Unet architecture.We also introduce a highlight detection module as a mask to guide the removal task.Thus,these two networks can be jointly trained in an effective manner.Thanks to the hierarchical and global properties of the transformer mechanism,our framework is able to establish relationships between continuous self-attention layers,making it possible to directly model the mapping between the diffuse area and the specular highlight area,and reduce indeterminacy within areas containing strong specular highlight reflection.Experiments on public benchmark and real-world images demonstrate that our approach outperforms state-of-the-art methods for both highlight detection and removal tasks.

Perspectives on point cloud-based 3D scene modeling and XR presentation within the cloud-edge-client architecture

With the support of edge computing,the synergy and collaboration among central cloud,edge cloud,and terminal devices form an integrated computing ecosystem known as the cloud-edge-client architecture.This integration unlocks the value of data and computational power,presenting significant opportunities for large-scale 3D scene modeling and XR presentation.In this paper,we explore the perspectives and highlight new challenges in 3D scene modeling and XR presentation based on point cloud within the cloud-edge-client integrated architecture.We also propose a novel cloud-edge-client integrated technology framework and a demonstration of municipal governance application to address these challenges.

金刚烷基微孔有机聚合物的合成与性能

微孔有机聚合物由于具有优异的热稳定性、化学稳定性、低密度、高比表面积、分子尺度的孔径分布等优点,在气体储存、气体吸附与分离、有机蒸气吸附、异相催化剂载体、水处理、功能材料等方面引起研究者们极大的兴趣。通常,分子构筑单元特别是在平面或空间中呈对称性的单元,是合成微孔有机聚合物的核心单位。在众多的构筑单元或单体中,多取代金刚烷化合物具有高空间对称性和刚性结构特点,已被成功地用作分子“结”与其他多种类型的连接单元(分子“杆”)来构建三维微孔有机聚合物,而且此类微孔有机聚合物在合成产率、结构稳定性、孔径分布、吸附分离等方面表现出许多特殊或优异的性质。本文介绍了目前由金刚烷结构单元构建的以下几种微孔有机聚合物在合成和性能方面的研究进展:苯环连接型、席夫碱连接型、酰亚胺连接型、富氮型(苯并咪唑和三嗪),详细分析和比较了这些聚合物在合成方法、结构特点、稳定性与吸附性能等方面的异同点。此外,介绍了几种其他新型的金刚烷基聚合物。最后提出基于金刚烷的微孔有机聚合物未来的研究方向与思路。

Synergetic effect of secondary nucleation and growth on the lithium carbonate particle size in the gas-liquid reactive crystallization of LiCl-NH3·H2O-CO2

In this study,the gas-liquid reactive crystallization of LiCl-NH3·H2O-CO2 was adopted to produce Li2CO3.The weakly alkaline nature of NH3·H2O in the absence of any recarbonation process resulted in a unimodal and easily controllable particle size distribution(PSD)of the obtained Li2CO3.The reaction temperature significantly influenced both the Li2CO3 particle size and PSD.By increasing the temperature from 25 to 60℃,the volume weighted mean particle size increased from 50.5 to 100.5μm,respectively.The Li2CO3 secondary nucleation rate and growth rate were obtained by focused beam reflectance measurements and a laser particle size analyzer,respectively.The secondary nucleation rate of Li2CO3 reduced as a function of temperature,whereas the growth rate increased.In addition to improving the surface energy of the crystals to enhance the growth process,higher temperatures also reduced the supersolubility of Li2CO3,which also plays a role to decrease the secondary nucleation rate.At a constant temperature,supersaturation affects the Li2CO3 particle size through the synergistic effect of secondary nucleation and growth.Hence,with improved supersaturation,the mean particle size of Li2CO3 decreased.The results provide a meaningful way to evaluate the crystallization process and to regulate the particle size.

Flow field design and experimental investigation of electrochemical machining on blisk

Flow field is a crucial factor to influence the stability and surface quality in the electrochemical machining(ECM)of blisks.A four-way flow mode was proposed to eliminate mixing regions of electrolyte at the leading and tailing edges.Two flow field models were described separately in this report:a W-shaped flow mode and a four-way flow mode.The flow field was analyzed through a finite element method.The results showed that,in comparison with the W-shaped flow mode,the distribution of electrolyte flow was more uniformed and the mixed region in the flow channel was improved.The pressure of the leading and tailing edges inlets was optimized,and optimal pressure of 0.6 MPa was determined.In addition,verification experiments were performed,and the results showed that the stability,efficiency,and quality of the profiles of the blisk blade manufactured by ECM were enhanced in the new flow mode.

Learning local shape descriptors for computing non-rigid dense correspondence

A discriminative local shape descriptor plays an important role in various applications.In this paper,we present a novel deep learning framework that derives discriminative local descriptors for deformable 3D shapes.We use local"geometry images"to encode the multi-scale local features of a point,via an intrinsic parameterization method based on geodesic polar coordinates.This new parameterization provides robust geometry images even for badly-shaped triangular meshes.Then a triplet network with shared architecture and parameters is used to perform deep metric learning;its aim is to distinguish between similar and dissimilar pairs of points.Additionally,a newly designed triplet loss function is minimized for improved,accurate training of the triplet network.To solve the dense correspondence problem,an efficient sampling approach is utilized to achieve a good compromise between training performance and descriptor quality.During testing,given a geometry image of a point of interest,our network outputs a discriminative local descriptor for it.Extensive testing of non-rigid dense shape matching on a variety of benchmarks demonstrates the superiority of the proposed descriptors over the state-of-the-art alternatives.

Analyzing surface sampling patterns using the localized pair correlation function

Point distributions with different characteristics have a crucial influence on graphics applications. Various analysis tools have been developed in recent years, mainly for blue noise sampling in Euclidean domains. In this paper, we present a new method to analyze the properties of general sampling patterns that are distributed on mesh surfaces. The core idea is to generalize to surfaces the pair correlation function(PCF) which has successfully been employed in sampling pattern analysis and synthesis in 2D and 3D. Experimental results demonstrate that the proposed approach can reveal correlations of point sets generated by a wide range of sampling algorithms. An acceleration technique is also suggested to improve the performance of the PCF.