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数字经济背景下农产品供应链模式问题及对策研究

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物流科技 2025年第1期48卷 140-144页

作者：冯帅韩坤洪燕阜阳师范大学商学院安徽阜阳236037

市场经济和科学技术的迅猛发展加速了数字信息技术向各行业领域的渗透,作为供应链的重要分支,农产品供应链亟需响应这一转变以适用数字经济新业态。通过对数字经济背景下不同技术和新兴产业所共同塑造的现有农产品供应链模式进行分析,... 详细信息

市场经济和科学技术的迅猛发展加速了数字信息技术向各行业领域的渗透,作为供应链的重要分支,农产品供应链亟需响应这一转变以适用数字经济新业态。通过对数字经济背景下不同技术和新兴产业所共同塑造的现有农产品供应链模式进行分析,尤其是当前阶段极具代表性的农产品供应链模式及其所存在的共性问题,进而针对各项问题具体提出相应的农产品供应链模式改进对策,以期对数字经济背景下农产品供应链模式的创新性发展提供帮助。

关键词：数字经济农产品供应链模式问题与对策

Microwave promoted one-pot synthesis of 3-(2′-amino-3′-cyano-4′-arylpyrid-6′-yl)coumarins

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Chinese Chemical Letters 2009年第1期20卷 37-39页

作者： Jian feng Zhou Gui Xia Gong feng Xia Zhu san Jun Zhi Department of Chemistry Huaiyin Teachers College Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials Huaian 223300 China School of Chemistry and Chemical Engineering Key Laboratory of Organic Synthesis of Jiangsu Province Suzhou University Suzhou 215123 China

A facile procedure for the synthesis of 3-（2′-amino-3′-cyano-4′-arylpyrid-6′-yl） coumarins are being reported starting from 3- acetylcoumarin, aromatic aldehydes and malononitrile. The reactions were carried out on microwave irradiation in good yield with short time and easy work-up. The structures of all the compounds have been confirmed on the basis of their analytical, IR, ^1H NMR, and mass spectral data.

关键词： 3-(2′-Amino-3′-cyano-4′arylpyrid-6′-yl) coumarin Aromatic aldehyde 3-Acetylcoumarin Microwave irradiation

Hypoxia inducible factor-1α mediates protective effects of ischemic preconditioning on ECV-304 endothelial cells

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World Journal of Gastroenterology 2007年第16期13卷 2369-2373页

作者： Liu-Bin Shi Jian-Hua Huang Bao-san han Department of Organ Transplantation Huashan Hospital Fudan University Shanghai 200040 China Institute of Integrative Medicine Huashan Hospital Fudan University Shanghai 200040 China Department of General Surgery Ruijin Hospital School of Medicine Shanghai Jiaotong University Shanghai 200025 China

AIM: To investigate whether hypoxia inducible factor-1α (HIF-1α) is linked to the protective effects of ischemic preconditioning (IP) on sinusoidal endothelial cells against ischemia/reperfusion injury. METHODS: Sinusoidal endothelial cell lines ECV-304 were cultured and divided into four groups: control group, cells were cultured in complete DMEM medium; cold anoxia/warm reoxygenation (A/R) group, cells were preserved in a 4℃ UW solution in a mixture of 95% N2 and 5% CO2 for 24 h; anoxia-preconditioning (APC) group, cells were treated with 4 cycles of short anoxia and reoxygenation before prolonged anoxia- preconditioning treatment; and anoxia-preconditioning and hypoxia inducible factor-1α (HIF-1α) inhibitor (I-HIF-1) group, cells were pretreated with 5 μm of HIF-1α inhibitor NS398 in DMEM medium before subjected to the same treatment as group APC. After the anoxia treatment, each group was reoxygenated in a mixture of 95% air and 5% CO2 incubator for 6 h. Cytoprotections were evaluated by cell viabilities from Trypan blue, lactate dehydrogenase (LDH) release rates, and intracellular cell adhesion molecule-1 (ICAM-1) expressions. Expressions of HIF-1α mRNA and HIF-1α protein from each group were determined by the RT-PCR method and Western blotting, respectively. RESULTS: Ischemia preconditioning increased cell viability, and reduced LDH release and ICAM-1 expressions. Ischemia preconditioning also upregulated the HIF-1α mRNA level and HIF-1α protein expression. However, all of these changes were reversed by HIF-1α inhibitor ***: Ischemia preconditioning effectively inhibited cold hypoxia/warm reoxygenation injury to endothelial cells, and the authors showed for the first time HIF-1α is causally linked to the protective effects of ischemic preconditioning on endothelial cells.

关键词： Preconditioning Anoxia/reoxygenation injury Reperfusion injury Endothelial cells Hypoxia inducible factor-1α

Theory of Nonequilibrium Coherent Transport Through an Interacting Mesoscopic Region Weakly Coupled to Electrodes

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Communications in Theoretical Physics 2003年第3X期40卷 369-374页

作者： ZHUYu LINTsung-han SUNQing-feng StateKeyLaboratoryforMesoscopicPhysicsandDepartmentofPhysics PekingUniversityBeijing100871China CenterforthePhysicsofMaterialsandDepartmentofPhysics McGillUniversityMontrealPQCanadaH3A2T8

We develop a theory for the nonequilibrium coherent transport through a mesoscopic region, based on the nonequilibrium Green function technique. The theory requires the weak coupling between the central mesoscopic region and the multiple electrodes, but allows arbitrary hopping and interaction in the central region. An equation determining the nonequilibrium distribution in the central interacting region is derived and plays an important role in the *** theory is applied to two special cases for demonstrations, revealing the novel effects associated with the combination of phase coherence, Coulomb interaction, and nonequilibrium distribution.

关键词：非平衡态一致性输运中观系统格林函数电子崩溃

Interactive design computation-a case study on quantum design paradigm

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Frontiers of Architectural Research 2013年第2期2卷 252-262页

作者： han feng HyperBODY Faculty of Architecture Delft University of Technology Delft 2628 BL The Netherlands

The ever-increasing comptexity of design processes fosters novet design computation modets to be employed in architecturat research and design in order to facilitate accurate data processing and refined decision making. These computation modets have enabled designers to work with comptex geometry and numeric design constraints to explore a whole new design field that is impossibte to explore without computation techniques. However, most current design computation modets foUow an automation-oriented paradigm that only dear with strictty defined problem solving and optimization, but fail in estabtishing an intuitive and interactive communication with designers. This lack of interaction reads to an unconscious rejection of non-parameterizabte design factors, which, reduces design computation models to specific design probtem sotving toots instead of operating as active design partners. This paper presents a non-deterministic design computation modeling approach derived from a discussion on quantum design paradigm, which emptoys rear-time user interaction as the co-driver to evotve user＋computation driven informed design outputs. model; *** Tootset, developed and applied in A case study of such a design computation a QuantumPointCloud workshop, will be illustrated in this paper. Expanded discussions on fabrication optimization and construction techniques from the QPC workshop will be addressed to conclude a comprehensive report.

关键词： Interactive designcomputation modeking Quantum Paradigm Hotwire cutting Point cloud Design constraint

Trot Gait Design and CPG Method for a Quadruped Robot

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Journal of Bionic Engineering 2014年第1期11卷 18-25页

作者： Jiaqi Zhang feng Gao Xiaolei han Xianbao Chen Xueying han School of Mechanical Engineering Shanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 P. R. China State Key Laboratory of Mechanical System and Vibration 800 Dongchuan Road Shanghai 200240 P. R. China Ecology Evolution and Marine Biology University of California at Santa Barbara CA 93106 USA

Developing efficient walking gaits for quadruped robots has intrigued investigators for years. Trot gait, as a fast locomotion gait, has been widely used in robot control. This paper follows the idea of the six determinants of gait and designs a trot gait for a parallel-leg quadruped robot, Baby Elephant. The walking period and step length are set as constants to maintain a relatively fast speed while changing different foot trajectories to test walking quality. Experiments show that kicking leg back improves body stability. Then, a steady and smooth trot gait is designed. Furthermore, inspired by Central Pattern Generators （CPG）, a series CPG model is proposed to achieve robust and dynamic trot gait. It is generally believed that CPG is capable of producing rhythmic movements, such as swimming, walking, and flying, even when isolated from brain and sensory inputs. The proposed CPG model, inspired by the series concept, can automatically learn the previous well-designed trot gait and reproduce it, and has the ability to change its walking frequency online as well. Experiments are done in real world to verify this method.

关键词： quadruped robot trot gait series CPG model foot trajectory

Singularity analysis for single gimbal control moment gyroscope system using space expansion method

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Chinese Journal of Aeronautics 2018年第4期31卷 782-794页

作者： Yunhua WU feng han Bing HUA Zhiming CHEN feng YU School of Astronautics Nanjing University of Aeronautics and Astronautics School of Astronautics Harbin Institute of Technology

Control Moment Gyroscope（CMG） is an effective candidate for agile satellites and large spacecraft attitude control because of its powerful torque amplification capability. The most serious situation, however, in using CMG is the inherent geometric singularity problem, where there＇s no torque output along a particular direction. Space expansion method has been proposed in this work for the singularity analysis. Based on inverse mapping transformation, an expanded Jacobian matrix which is a full rank square matrix is obtained. The singular angle sets of the 3-parallel cluster and pyramid cluster are distinguished using space expansion method. An effective hybrid steering strategy, able to deal with the elliptic singularity, is further proposed. Simulation results demonstrate the excellent performance of the proposed steering logic compared to the generalized singular robust logic and pseudo inverse logic in terms of energy consumption and torque error.

关键词： Agile spacecraft Control moment gyro Singularity analysis Space expansion method Steering strategy

Unstructured Road Extraction in UAV Images based on Lightweight Model

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 372-384页

作者： Di Zhang Qichao An Xiaoxue feng Ronghua Liu Jun han feng Pan School of Automation Beijing Institute of TechnologyBeijing 100081China Tianjin Institute of Maritime Navigation Instruments Tianjin 300130China The 716th Research Institute of China Shipbuilding Group Co. LtdJiangsu 222061China

There is no unified planning standard for unstructured roads,and the morphological structures of these roads are complex and *** is important to maintain a balance between accuracy and speed for unstructured road extraction *** road extraction algorithms based on deep learning have problems such as high model complexity,high computational cost,and the inability to adapt to current edge computing ***,it is best to use lightweight network *** the need for lightweight models and the characteristics of unstructured roads with different pattern shapes,such as blocks and strips,a TMB(Triple Multi-Block)feature extraction module is proposed,and the overall structure of the TMBNet network is *** TMB module was compared with SS-nbt,Non-bottleneck-1D,and other modules via *** feasibility and effectiveness of the TMB module design were proven through experiments and *** comparison experiment,using multiple convolution kernel categories,proved that the TMB module can improve the segmentation accuracy of the *** comparison with different semantic segmentation networks demonstrates that the TMBNet network has advantages in terms of unstructured road extraction.

关键词： Unstructured road Lightweight model Triple Multi-Block(TMB) Semantic segmentation net

Does poverty-alleviation-based industry development improve farmers'livelihood capital?

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Journal of Integrative Agriculture 2021年第4期20卷 915-926页

作者： LIU Ming-yue feng Xiao-long WANG san-gui ZHONG Yu Institute of Agricultural Economics and Development Chinese Academy of Agricultural SciencesBeijing 100081P.R.China College of Economics and Management China Agricultural UniversityBeijing 100083P.R.China School of Agricultural Economics and Rural Development Renmin University of ChinaBeijing 100872P.R.China

Targeted poverty alleviation is a unique approach adopted in China to help achieve the vision of a moderately prosperous society in all aspects and the"Chinese Dream".Industrial development as a means of poverty alleviation is an integral part of the"Five-pronged Poverty Alleviation Measures"Project of targeted poverty alleviation,and a critical foundation for other poverty alleviation *** this study,a comprehensive evaluation method was used to measure farmers'livelihood based on the framework of sustainable ***,the effects of industrial development on farmers'livelihood capital were estimated by employing the propensity score matching combined with the difference-in-differences(PSM-DID)*** suggest that industrial development had a significantly positive effect on the livelihood capital of *** development can significantly enhance farmers'human,social and financial capital,while it cannot significantly affect the natural and physical *** development had heterogeneous effects on farmers'livelihood capital,more efficiently impacting on the non-poor than the *** effects on farmers'livelihood capital varied across regions,with Guizhou experiencing a larger effect than ***,the effect was insignificant for farmers in *** improve farmers'livelihood capital,it is necessary to take measures to strengthen their human capital,promote the innovation of financial products,and make good use of their social capital;it is also essential to strengthen the support of industrial development to the poor.

关键词： targeted poverty alleviation poverty alleviation by industrial development the poor livelihood capital PSM-DID approach