检索结果-南通市图书馆

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

级联混合模型引导的实时柑橘采摘点定位方法

中国图象图形学报 2024年第10期29卷 3130-3143页

作者：梁云刘云帆林毅申姜伟鹏黄梓帆华南农业大学数学与信息学院广州510642

目的柑橘是我国最常见的水果之一,目前多以人工采摘为主,成本高、效率低等问题严重制约规模化生产,因此柑橘自动采摘成为近年的研究热点。但是,柑橘生长环境复杂、枝条形态各异、枝叶和果实互遮挡严重,如何精准实时地定位采摘点成为自... 详细信息

目的柑橘是我国最常见的水果之一,目前多以人工采摘为主,成本高、效率低等问题严重制约规模化生产,因此柑橘自动采摘成为近年的研究热点。但是,柑橘生长环境复杂、枝条形态各异、枝叶和果实互遮挡严重,如何精准实时地定位采摘点成为自动采摘的关键。通过构建级联混合网络模型,提出了一种通用且高效的柑橘采摘点自动精准定位方法。方法构建团簇框生成模型和枝条稀疏实例分割模型,对两者进行级联混合实现实时柑橘采摘点定位。首先,构建柑橘果实检测网络,提出团簇框生成模型,该模型通过特征提取、果实检测框生成和DBSCAN(density-based spatial clustering of applications with noise)果实密度聚类,实时地生成图像内果实数目最多的团簇框坐标;然后,提出融合亮度先验的枝条稀疏分割模型,该模型以团簇框内的图像作为输入,有效降低背景枝条的干扰,通过融合亮度先验的稀疏实例激活图,实时地分割出与果实相连接枝条实例;最后基于分割结果搜索果实采摘点定位坐标。结果经过长时间户外采集制作了柑橘果实检测数据集CFDD(citrus fruit detection dataset)和柑橘枝条分割数据集CBSD(citrus branch segmentation dataset)。这两个数据集由成熟果实、未成熟果实组成,包含晴天、阴天、顺光和逆光等挑战,总共37000幅图像。在该数据集上本文方法的采摘点定位精准度达到了95.77%,帧率(frames per second,FPS)达到了28.21帧/s。结论本文方法在果实采摘点定位方面取得较好进展,能够快速且准确地获取柑橘采摘点,并且提供配套的机械臂采摘设备可供该采摘点定位算法的落地使用,为柑橘产业发展提供有力支持。

关键词：采摘机器人采摘点定位方法团簇框生成器亮度先验枝条稀疏分割模型

An epidermal electrode based triboelectric walking energy harvester for wearable wireless sensing applications

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第3期67卷 949-957页

作者： CHANG ShiYuan LIU FuHai CHEN JinKai XIA LianBin ZHOU Hao jiang JingYang DONG Kang ZHANG ChenHao WU Yun CHEN Jin XUAN weipeng SUN LingLing JIN Hao DONG ShuRong LUO JiKui Ministry of Education Key Laboratory of RF Circuits and Systems Hangzhou Dianzi UniversityHangzhou 310018China Special Equipment College Hangzhou Vocational&Technical CollegeHangzhou 310018China College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 330027China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311200China

Harvesting bio-kinetic energy using a triboelectric nanogenerator(TENG) is one of the promising routes to solve the sustainable energy supply problem for wearable electronics. However, additional materials, complex fabricating processes or specific mechanical structures are needed for existing TENGs to harvest bio-kinetic energy. Besides, they need to be tightly attached to the human body, which may result in detachment and malfunction under tense human motion. Herein, an intrinsic epidermal electrode-based TENG(E-TENG) is proposed to harvest human walking energy. The wearing shoes and ground are used as tribo-materials, and the human epidermis is used as the back electrode of the E-TENG. Compared with the traditional TENGs,the E-TENG does not need any additional tribo-materials and complex mechanical structures. Under optimal conditions, the voltage output of E-TENG can reach 914 V. E-TENG has been used as a self-powered warning sensor and pedometer sensor for demonstration. Furthermore, E-TENG based self-powered wireless sensor system has been developed using a newly designed micro energy electronic switch(MEES). Ambient ultraviolet intensity, temperature and humidity information can be monitored and then transmitted to mobile phone every 3.5 min, demonstrating great potential for widespread wearable applications.

关键词： triboelectric nanogenerator wearable wireless sensing self-powered

Synthesis and Charaterization of 4-Bromo-2-nitro-biphenyl by Suzuki Coupling Reaction

在线全文

学校读者我要写书评

暂无评论

Synthesis and Charaterization of 4-Bromo-2-nitro-biphenyl by...

Association between hyperglycemia at ICU admission and postoperative acute kidney injury in patients undergoing cardiac surgery:Analysis of the MIMIC-IV database

河南省化学会2016年学术年会

作者： Yuru Liu Xianying Duan weipeng jiang Haitao Chen Wenxin Wang Ji Li Institution of Chemistry Henan Academy of Sciences

The Suzuki coupling reaction of organic boron involved has attracted great attention. For this reaction,it has the features that the mild reaction conditions, substrate obtained easily, and functional group with good tolerance(such as amino, carboxyl and aldehyde, nitro group, cyano group, and halogen),moreover, products easily separated, seldom affected by the steric hindrance group, high efficiency,high regioselectivity and enantioselectivity. These advantages help it win the 2010 Nobel Prize in chemistry. Biphenyl compound is a kind of very important chemical intermediate, which is widely used in the fields of medicine, fuel, organic conductor, semiconductor and liquid crystal materials. In organic synthesis, the synthesis of these compounds is often based on the organic metal coupling *** this paper, 4-Bromo-2-nitro-biphenyl has been synthesized by Suzuki coupling. The effects of several factors on the reaction filed, such as temperature, time and base used in the reaction, are investigated. This obtained target product is characterized and analyzed by Chromatography, IR,NMR and GC-MS et al.

关键词： Suzuki coupling reaction 4-Bromo-2-nitro-biphenyl synthesis

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Intensive Medicine 2024年第4期4卷 526-536页

作者： Juan Ruan weipeng Huang Jun jiang Chang Hu Yiming Li Zhiyong Peng Shuhan Cai Department of Critical Care Medicine Zhongnan Hospital of Wuhan UniversityWuhanHubeiChina Clinical Research Center of Hubei Critical Care Medicine WuhanHubeiChina Department of Critical Care Medicine Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhouZhejiangChina

Background:This study aimed to explore the correlation between hyperglycemia at intensive care unit(ICU)admission and the incidence of acute kidney injury(AKI)in patients after cardiac ***:We conducted a retrospective cohort study,in which clinical data were extracted from the Medical Information Mart for Intensive Care(MIMIC)-IV ***(≥18 years)in the database who were admitted to the cardiovascular intensive care unit after cardiac surgery were *** primary outcome was the incidence of AKI within 7 days following ICU *** outcomes included ICU mortality,hospital mortality,ICU length of stay,and the 28-day and 90-day *** Cox regression analysis was used to assess the association between ICU-admission hyperglycemia and AKI incidence within 7 days of ICU *** adjustment strategies were used to adjust for potential *** were divided into three groups according to their highest blood glucose levels recorded within 24 h of ICU admission:no hyperglycemia(<140 mg/dL),mild hyperglycemia(140-200 mg/dL),and severe hyperglycemia(≥200 mg/dL).Results:Of the 6905 included patients,2201(31.9%)were female,and the median(IQR)age was 68.2(60.1-75.9)*** all,1836(26.6%)patients had severe *** incidence of AKI within 7 days of ICU admission,ICU mortality,and hospital mortality was significantly higher in patients with severe admission hyperglycemia than those with mild hyperglycemia or no hyperglycemia(80.3%vs.73.6% and 61.2%,respec-tively;2.8%vs.0.9% and 1.9%,respectively;and 3.4%vs.1.2% and 2.5%,respectively;all P<0.001).Severe hyperglycemia was a risk factor for 7-day AKI(Model 1:hazard ratio[HR]=1.4809,95%confidence interval[CI]:1.3126 to 1.6707;Model 2:HR=1.1639,95%CI:1.0176 to 1.3313;Model 3:HR=1.2014,95%CI:1.0490 to 1.3760;all P<0.050).Patients with normal glucose levels(glucose levels<140 mg/dL)had a higher 28-day mortality rate than those with severe hyperglycemia

关键词： Hyperglycemia Cardiac surgery Acute kidney injury Mortality MIMIC database

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于张量分解的知识超图链接预测模型

计算机研究与发展 2021年第8期58卷 1599-1611页

作者：王培妍段磊郭正山蒋为鹏张译丹四川大学计算机学院成都610065

知识超图包含了现实世界中的事实,并给出这些事实的结构化表示.但知识超图无法包括所有事实,所以其是高度不完整的.链接预测方法致力于根据现有实体间链接推理缺失链接,因此广泛应用于知识库补全.目前大多数研究集中于二元关系知识图谱... 详细信息

知识超图包含了现实世界中的事实,并给出这些事实的结构化表示.但知识超图无法包括所有事实,所以其是高度不完整的.链接预测方法致力于根据现有实体间链接推理缺失链接,因此广泛应用于知识库补全.目前大多数研究集中于二元关系知识图谱的补全.然而,现实世界中实体间的关系通常是非二元的,即关系中涉及的实体通常多于2个.相较于知识图谱,知识超图能够以一种灵活且自然的方式来表示这些复杂的多元关系.对此,设计一个基于张量分解的知识超图链接预测模型Typer,显式地为不同关系以及不同位置上实体的角色建模,并对关系进行细化分解以提升模型性能.同时,考虑到促进实体与关系间的信息流动有助于学习实体和关系的嵌入表示,提出窗口的概念,以增加实体与关系的交互.此外,证明了Typer模型具有完全表达性,并给出了使模型具有完全表达性的嵌入表示维度边界.在多个公开真实知识超图数据集上进行了详实的实验,实验表明Typer模型能有效解决知识超图链接预测问题,并在所有数据集上取得了较其他方法更好的结果.

关键词：知识超图链接预测知识库补全多元关系张量分解嵌入学习

Heat Transfer and Friction Characteristics of Printed Circuit Heat Exchangers with Different Channel Structures for S-CO_(2) Power System

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第3期33卷 1132-1147页

作者： jiang Tao LI Mingjia Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an710049China School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

Printed circuit heat exchanger(PCHE)has been widely used in supercritical carbon dioxide(S-CO_(2))power systems because of its high heat transfer efficiency and good ***,due to the large variety of PCHE configurations,channel selection in practical applications lacks a ***,this paper discussed the heat transfer and friction characteristics and the synergy of three fields in the channel under the guidance of the field synergy principle for four typical PCHE ***,the comprehensive performance of four channels was ***,the heat transfer and friction factor correlations for S-CO_(2)in four channels were *** findings demonstrate that the synergy of velocity and pressure fields of the straight channel PCHE is better(β≈180°),so its resistance loss is relatively *** zigzag and sinusoidal wavy channels and the airfoil fins can reduce the angle a between the temperature gradient and velocity,thus enhancing the heat *** sinusoidal wavy channel can reduce flow resistance compared to the zigzag channel due to the rounded *** streamlined airfoil structure can guide the flow and reduce backflow,thus reducing resistance *** the range of Re studied in this paper,the maximum error of the proposed heat transfer and friction factor correlations of PCHE is 7.0%,which shows good fitting *** research in this paper can provide a reference for the selection and design of PCHE with different channel configurations.

关键词： printed circuit heat exchanger supercritical carbon dioxide typical channel structure field synergy analysis

An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： Yang jiang Ming Cheng School of Electrical Engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous ***,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic *** order to solve these problems,a new signal demodulation method is proposed in this *** proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter *** addition,a new magnetic polarity detection method is proposed,which is robust to current measurement ***,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination

Co/CoO heterojunction rich in oxygen vacancies introduced by O2 plasma embedded in mesoporous walls of carbon nanoboxes covered with carbon nanotubes for rechargeable zinc-air battery

在线全文

学校读者我要写书评

暂无评论

Carbon Energy 2024年第7期6卷 14-25页

作者： Leijun Ye Weiheng Chen Zhong-Jie jiang Zhongqing jiang Key Laboratory of Optical Field Manipulation of Zhejiang Province Department of PhysicsZhejiang Sci-Tech UniversityHangzhouChina Department of Mechanical Engineering Ningbo University of TechnologyNingboChina Guangzhou Key Laboratory for Surface Chemistry of Energy Materials Guangdong Engineering and Technology Research Center for Surface Chemistry of Energy MaterialsCollege of Environment and EnergySouth China University of TechnologyGuangzhouChina

Herein,Co/CoO heterojunction nanoparticles(NPs)rich in oxygen vacancies embedded in mesoporous walls of nitrogen-doped hollow carbon nanoboxes coupled with nitrogen-doped carbon nanotubes(P-Co/CoOV@NHCNB@NCNT)are well designed through zeolite-imidazole framework(ZIF-67)carbonization,chemical vapor deposition,and O_(2) plasma *** a result,the threedimensional NHCNBs coupled with NCNTs and unique heterojunction with rich oxygen vacancies reduce the charge transport resistance and accelerate the catalytic reaction rate of the P-Co/CoOV@NHCNB@NCNT,and they display exceedingly good electrocatalytic performance for oxygen reduction reaction(ORR,halfwave potential[EORR,1/2=0.855 V *** hydrogen electrode])and oxygen evolution reaction(OER,overpotential(η_(OER,10)=377mV@10mA cm^(−2)),which exceeds that of the commercial Pt/C+RuO_(2) and most of the formerly reported ***,both the aqueous and flexible foldable all-solid-state rechargeable zinc-air batteries(ZABs)assembled with the P-Co/CoOV@NHCNB@NCNT catalyst reveal a large maximum power density and outstanding long-term cycling ***-principles density functional theory calculations show that the formation of heterojunctions and oxygen vacancies enhances conductivity,reduces reaction energy barriers,and accelerates reaction kinetics *** work opens up a new avenue for the facile construction of highly active,structurally stable,and cost-effective bifunctional catalysts for ZABs.

关键词： heterojunction oxygen evolution/reduction reaction oxygen vacancies rechargeable zinc–air battery three‐dimensional nitrogen‐doped hollow carbon nanoboxes

Hybrid rogue waves and breather solutions on the double-periodic background for the Kundu-DNLS equation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第5期76卷 33-48页

作者： DongZhu jiang Zhaqilao College of Mathematics Science Inner Mongolia Normal UniversityHohhot 01022China Center for Applied Mathematical Science Inner MongoliaHohhot 010022China

In this paper,by using the Darboux transformation(DT)method and the Taylor expansion method,a new nth-order determinant of the hybrid rogue waves and breathers solution on the double-periodic background of the Kundu-DNLS equation is constructed when n is *** and rogue waves can be obtained from this determinant,*** to this,the hybrid rogue waves and breathers solutions on the different periodic backgrounds are given explicitly,including the single-periodic background,the double-periodic background and the plane wave background by selecting different *** addition,the form of the obtained solutions is summarized.

关键词： double-periodic background hybrid rogue waves and breather darboux transformation Kundu-DNLS equation