新时代下我国数字农业发展的机遇、不足及对策

近年来,在政策推动及市场环境的变化下,我国数字农业发展取得了一定成效,但也依然面临着人才短缺、技术薄弱、主动投资不足等挑战。对当下我国数字农业发展的现状、机遇和挑战进行分析研究,并给出相关对策建议。     

干耦合超声波测试技术及其岩石动静参量测试应用

岩体非线性特征随深度增加不断凸显,其力学参量现场实时精确测量及长期监测,为地应力解除过程中岩体变化特征及应力监测提供了必要的基础。然而目前岩石力学参量测定多基于室内力学试验,时效性及拟合方法都会对测试结果带来误差。传统耦合超声波发射、接收探头对接触面平整性要求高,无法实现布置于现场钻孔内的长效监测。基于干耦合点接触声波探头测速技术,通过对声波发射、接收探头设计,电路板稳定性及去噪算法研究,研发出具有瞬时采集、无线传输功能的数字化波速采集系统。通过对同一区域取自现场加工的?50 mm×100 mm花岗岩岩样及地应力解除岩芯,分别进行室内力学试验及波速测定,以计算获取相应静态、动态弹性模量。结果表明:首先,自研发基于干耦合点接触声波测速采集系统,对不同工作接触面适应性较好,数据误差在规范允许范围内。其次,对于同一区域相同岩性不同尺度、形态的岩样,其动态、静态弹性模量关系彼此间具有适用性。这就为现场基于干耦合点接触声波测速计算获得的岩体动态弹性模量,推算其静态弹性模量提供了依据。进一步的,基于干耦合点接触声波测速数字化采集系统,岩体动、静态力学参数在现场地应力岩芯解除过程及岩体长期监测过程中的实时采集及分析研究,具有一定的可行性。     

Chemistry Education Fostering Creativity in the Digital Era

Renewing undergraduate education in the chemical sciences to foster creativity using research, visualization and connectivity resources has substantial benefits, but requires changes in the curriculum and teaching methodology as well as in academic teaching and human resource conventional policies.     

Morphology,adipocyte size,and fatty acid analysis of dairy cattle digital cushions,and the effect of body condition score and age

The digital cushion is an essential part of maintaining a healthy foot, working to dissipate foot strike and body weight forces and lameness from claw horn disruption lesions. Despite the importance of the digital cushion, little is known about the basic anatomy, adipocyte morphology, and fatty acid composition in relation to age, limb position, and body condition score. In total, 60 claws (from 17 cows) were selected and collected from a herd, ensuring that body condition score data and computed micro-tomography were known for each animal. Digital cushion tissue underwent histological staining combined with stereology, systematic random sampling, and cell morphology analysis, in addition to lipid extraction followed by fatty acid analysis. The results describe digital cushion architecture and adipocyte sizes. Adipocyte size was similar across all 4 claws (distal left lateral and medial and distal right lateral and medial) and across the ages (aged 2–7 yr); however, animals with body condition score of 3.00 or more at slaughter had a significantly increased cell size in comparison to those with a score of less than 2.50. Of 37 fatty acid methyl esters identified, 5 differed between either the body condition score or different age groups. C10:0 capric acid, C14:0 myristic acid, C15:0 pentadecanoic acid, and C20:0 arachidic acid percentages were all lesser in lower body condition score cows, whereas C22:1n-9 erucic acid measurements were lesser in younger cows. Saturated fatty acid, monounsaturated fatty acid, and polyunsaturated fatty acid percentages were not altered in the different claws, ages, or body condition score groups. Triglyceride quantities did not differ for claw position or age but had decreased quantities in lower body condition score animals. Digital cushion anatomy, cellular morphology, and fatty acid composition have been described in general and also in animals with differing ages, body condition scores, and in the differing claws. Understanding fat deposition, mobilization, and composition are essential in not only understanding the roles that the digital cushion plays but also in preventing disorders and maintaining cattle health and welfare.     

数字技术环境下景观规划设计教学改革与实践

设计创新能力培养已成为21世纪风景园林学规划设计教学核心，在此背景下，由知识传输导向的教学模式正逐步转变为由设计与科研并肩引领知识增长的教学模式，数字化景观规划设计教学体系与方法成为当代风景园林教育亟待充实并应用的重要内容。立足风景园林教学前沿，基于对当代风景园林规划设计教育的系统把握，以东南大学风景园林专业教学实践为例，提出整合数字景观技术平台，构建“浸入式”数字技术教学环境，实现数字平台与教学体系的协同创新；继而针对传统教学方法局限，利用数字化教学平台进行“耦合教学法”创新实践，加强实证性知识体系集成融合，实现风景园林规划设计课程教学模式的系统探索与实践。     

数字经济时代网络市场监管创新的思考

数字经济时代,新技术、新产业、新业态、新模式加速孕育,网络市场竞争态势愈加复杂、多变,监管创新成为重要课题。网络市场监管工作应当确立稳定、可预期的监管原则,并落实好包容审慎、事中事后监管、协同监管等原则;对关系到国家安全、社会稳定和公众生命健康等底线性问题,监管不能缺位,而应继续严格审查监管。从创新监管原则的宏观研究,以及大数据监管、提升电子取证能力等监管手段的具体研究等维度,对监管创新进行了深度思考。     

To shop or not: Understanding Chinese consumers’ live-stream shopping intentions from the perspectives of uses and gratifications,perceived network size,perceptions of digital celebrities,and shopping orientations

Live-stream shopping is experiencing unprecedented growth. However, research in live-stream commerce is in its infancy. The current study integrates uses and gratifications, perceived network size, perceptions of digital celebrities, and experience-focused shopping orientation to clarify motivations for live-stream shopping. Accordingly, the current study used a questionnaire to collect data from 339 Chinese consumers and structural equation modeling to analyze data in AMOS 24. In this study, individuals were motivated by gratifications that were (1) hedonic (perceived enjoyment), (2) utilitarian (self-presentation), and (3) social (social presence and interaction). Moreover, perceived network size significantly predicted perceived enjoyment, social interaction, social presence, and utility. In addition, experience-focused shopping orientation mediated the relationships among perceived enjoyment, self-presentation, social interaction, and live-stream shopping intentions. Finally, the mediating roles of the perceptions of digital celebrities in the relationships of perceived network size with perceived utility, perceived engagement, social interaction, social presence, and self-presentation were confirmed.     

Three-dimensional complex construct fabrication of illite by digital light processing-based additive manufacturing technology

Illite is a group of clay minerals that are expected to be widely used in catalyst fabrication, radioactive element adsorption, and so forth, due to its excellent adsorption properties. However, the shape control limitation of the illite product should be overcome to maximize its utilization and properties. We herein propose additive manufacturing (AM) as one of the best solutions to solve this structural drawback. Digital light processing (DLP) technology with the film-type of the material supplying system was adapted instead of the general vat-type DLP system to increase illite printability. The photo-curability and printability of illite-contained photocurable suspension were optimized. The color effect due to different ferric oxide content in yellow- and white-illite which influence the photopolymerization process also adjusted thoroughly. White illite showed better photo-curability and could be increased solid loading than yellow illite. The defect-free illite products with three-dimensional complex structures, which cannot be produced by typical ceramic processes, were obtained by DLP technology for both yellow- and white-illite after sintering at 1100°C. The overcoming of shape control limitation of illites by ceramic AM proved in this study has excellent potential for expanding illite utilities in various applications.