期刊文献+
共找到6,393篇文章
< 1 2 250 >
每页显示 20 50 100
Low-Cost Federated Broad Learning for Privacy-Preserved Knowledge Sharing in the RIS-Aided Internet of Vehicles 被引量:1
1
作者 Xiaoming Yuan Jiahui Chen +4 位作者 Ning Zhang Qiang(John)Ye Changle Li Chunsheng Zhu Xuemin Sherman Shen 《Engineering》 SCIE EI CAS CSCD 2024年第2期178-189,共12页
High-efficiency and low-cost knowledge sharing can improve the decision-making ability of autonomous vehicles by mining knowledge from the Internet of Vehicles(IoVs).However,it is challenging to ensure high efficiency... High-efficiency and low-cost knowledge sharing can improve the decision-making ability of autonomous vehicles by mining knowledge from the Internet of Vehicles(IoVs).However,it is challenging to ensure high efficiency of local data learning models while preventing privacy leakage in a high mobility environment.In order to protect data privacy and improve data learning efficiency in knowledge sharing,we propose an asynchronous federated broad learning(FBL)framework that integrates broad learning(BL)into federated learning(FL).In FBL,we design a broad fully connected model(BFCM)as a local model for training client data.To enhance the wireless channel quality for knowledge sharing and reduce the communication and computation cost of participating clients,we construct a joint resource allocation and reconfigurable intelligent surface(RIS)configuration optimization framework for FBL.The problem is decoupled into two convex subproblems.Aiming to improve the resource scheduling efficiency in FBL,a double Davidon–Fletcher–Powell(DDFP)algorithm is presented to solve the time slot allocation and RIS configuration problem.Based on the results of resource scheduling,we design a reward-allocation algorithm based on federated incentive learning(FIL)in FBL to compensate clients for their costs.The simulation results show that the proposed FBL framework achieves better performance than the comparison models in terms of efficiency,accuracy,and cost for knowledge sharing in the IoV. 展开更多
关键词 Knowledge sharing Internet of Vehicles Federated learning broad learning Reconfigurable intelligent surfaces Resource allocation
下载PDF
Spontaneous Paravesical and Broad Ligament Hematoma after Vaginal Delivery Had Uterine Artery Embolization after Evacuating the Hematoma
2
作者 Aayat Jaaffar Naseeb Abrar Majdi Al Nasheet 《Open Journal of Obstetrics and Gynecology》 2024年第3期480-486,共7页
Broad ligament hematoma is typically seen during cesarean section due to rupture of branches of uterine and vaginal vessels and it’s rare to be seen post-normal vaginal delivery. Addressing puerperal hematomas postpa... Broad ligament hematoma is typically seen during cesarean section due to rupture of branches of uterine and vaginal vessels and it’s rare to be seen post-normal vaginal delivery. Addressing puerperal hematomas postpartum presents considerable challenges for obstetric care providers. While hematomas such as those affecting the vulva, vulvovaginal region, or paravaginal area are frequently encountered, retroperitoneal hematomas are rare and notably pose a greater risk to the life of the patient. The medical literature contains scant case reports on retroperitoneal hematomas, with no consensus on a definitive treatment approach. Pelvic arterial embolization has emerged as both a sensible and increasingly preferred method for treating these hematomas recently, but its application is contingent upon the patient maintaining hemodynamic stability and the availability of a specialized interventional embolization unit. In our case, we are presenting a very rare case of a 31-year-old primigravida female with a history of in vitro fertilization pregnancy. She delivered a normal vaginal delivery at 31 weeks gestation. Unfortunately, she experienced multiple complications intrapartum, including preeclampsia and placental abruption. These complications increased her risk of developing a broad ligament hematoma. 展开更多
关键词 broad Ligament Paravesical Hematoma Spontaneous Hematoma Uterine Artery Embolization Retroperitoneal Hematoma Vaginal Delivery
下载PDF
High efficient broad-spectrum Bradyrhizobium elkanii Y63-1 被引量:1
3
作者 Piao Leng Fuxiao Jin +13 位作者 Song Li Yi Huang Chanjuan Zhang Zhihui Shan Zhonglu Yang Limiao Chen Dong Cao Qingnan Hao Wei Guo Hongli Yang Shuilian Chen Xinan Zhou Songli Yuan Haifeng Chen 《Oil Crop Science》 CSCD 2023年第4期228-235,共8页
Soybean(Glycine max),the primary source of high-quality plant protein,plays a crucial role as a grain and oil crop in China.Harnessing the full potential of symbiotic nitrogen fixation in soybean production holds imme... Soybean(Glycine max),the primary source of high-quality plant protein,plays a crucial role as a grain and oil crop in China.Harnessing the full potential of symbiotic nitrogen fixation in soybean production holds immense significance for agriculture and ecology alike.Zhongdou 63,a newly developed early-maturing summer soybean cultivar in 2021,exhibits remarkable traits such as high yield,superior quality,multi-resistance,and wide adaptability.In this study,eight distinct rhizobia strains from diverse regions were meticulously screened to identify highly effective strains specifically suited for Zhongdou 63.The aboveground biomass,plant height,chlorophyll content,root length,nodule number,and nodule dry weight of Zhongdou 63 were measured and the data were subjected to statistical analysis.The results demonstrated that Y63-1 is a predominant strain of Zhongdou 63.Subsequently,we conducted further investigations on the broad-spectrum nodulation characteristics of Y63-1.Ten representative soybean cultivars were individually inoculated with Y63-1 and subsequently analyzed for nodule numbers and nodule dry weight in their symbiotic systems with rhizobia.The findings revealed that Y63-1 effectively formed nodules with all ten soybean varieties tested.In summary,our current study identified highly efficient broad-spectrum Bradyrhizobium elkanii strain Y63-1 as the predominant strain in Zhongdou 63 and provided a theoretical foundation for enhancing yield potential not only in Zhongdou 63 but also in other varieties through inoculation with highly efficient rhizobia in production. 展开更多
关键词 Soybean RHIZOBIUM Nodule symbiosis NODULATION broad spectrum
下载PDF
Mulching broad ridges with a woven polypropylene fabric increases the growth and yield of young pear trees ‘Yuluxiang' in the North China Plain 被引量:1
4
作者 Yang Wu Mingde Sun Songzhong Liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第3期414-424,共11页
Unlike traditional ridging, mulching broad ridges with a woven polypropylene fabric (WPF) can reduce soil evaporation during the drought season and avoid long saturation time in the root zone of pear trees during the ... Unlike traditional ridging, mulching broad ridges with a woven polypropylene fabric (WPF) can reduce soil evaporation during the drought season and avoid long saturation time in the root zone of pear trees during the rainy season. In this study, field experiments were conducted from 2017 to 2020 in a pear orchard in the North China Plain to investigate the effects of mulching broad ridges (0.3 m in height and 2 m in width) with WPF on soil temperature and moisture, nitrogen leaching, vegetative and reproductive growth of young pear trees(Pyrus bretschneideri Rehd.‘Yuluxiang’). The experiments involved two treatments, namely, control (traditional no-ridge planting without mulching) and mulching broad ridges with WPF (RM treatment). The results showed that the RM treatment increased soil moisture and temperature and decreased nitrogen leaching, resulting in vigorous growth of the young pear trees. Moreover, the RM treatment increased the tree trunk cross-sectional area and height of the young pear trees by 37%and 8%in 2020, respectively. The nitrate nitrogen content at the soil layer depth of 0-30 cm was significantly higher in the RM than that in control. Furthermore, the RM treatment significantly increased the fruit yield due to larger tree size. In addition, compared with control, significantly higher fruit soluble solid content of RM treatment was detected in 2020. High precipitation (423 mm) occurred during fruit enlargement stage in 2020, RM treatment decreased the rainfall infiltration in the ridge and the soil moisture in root region, resulting in the improvement of fruit quality, compared with control.Therefore, mulching broad ridges with WPF can be implemented to increase soil moisture during drought season, soil temperature, and nitrate nitrogen content, thereby improving the growth and fruit yield of young pear trees. Additionally, it can reduce soil moisture in the root zone during the rainy season and improve the fruit quality of the trees. Finally, it can reduce nitrate nitrogen leaching, thereby reducing environmental pollution. 展开更多
关键词 Pyrus bretschneideri Rehd Mulching broad ridges Trunk cross-sectional area Yield efficiency Soil water content Soil temperature
下载PDF
Target tracking method of Siamese networks based on the broad learning system
5
作者 Dan Zhang C.L.Philip Chen +2 位作者 Tieshan Li Yi Zuo Nguyen Quang Duy 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第3期1043-1057,共15页
Target tracking has a wide range of applications in intelligent transportation,real‐time monitoring,human‐computer interaction and other aspects.However,in the tracking process,the target is prone to deformation,occ... Target tracking has a wide range of applications in intelligent transportation,real‐time monitoring,human‐computer interaction and other aspects.However,in the tracking process,the target is prone to deformation,occlusion,loss,scale variation,background clutter,illumination variation,etc.,which bring great challenges to realize accurate and real‐time tracking.Tracking based on Siamese networks promotes the application of deep learning in the field of target tracking,ensuring both accuracy and real‐time performance.However,due to its offline training,it is difficult to deal with the fast motion,serious occlusion,loss and deformation of the target during tracking.Therefore,it is very helpful to improve the performance of the Siamese networks by learning new features of the target quickly and updating the target position in time online.The broad learning system(BLS)has a simple network structure,high learning efficiency,and strong feature learning ability.Aiming at the problems of Siamese networks and the characteristics of BLS,a target tracking method based on BLS is proposed.The method combines offline training with fast online learning of new features,which not only adopts the powerful feature representation ability of deep learning,but also skillfully uses the BLS for re‐learning and re‐detection.The broad re‐learning information is used for re‐detection when the target tracking appears serious occlusion and so on,so as to change the selection of the Siamese networks search area,solve the problem that the search range cannot meet the fast motion of the target,and improve the adaptability.Experimental results show that the proposed method achieves good results on three challenging datasets and improves the performance of the basic algorithm in difficult scenarios. 展开更多
关键词 broad learning system siamese network target tracking
下载PDF
Closed loop ileus caused by a defect in the broad ligament:A case report
6
作者 Isabel Zucal Christian A Nebiker 《World Journal of Clinical Cases》 SCIE 2023年第5期1182-1187,共6页
BACKGROUND Closed loop ileus caused by entrapment of bowel in a defect of the broad ligament is a rarity.Only a few cases have been reported in the literature.CASE SUMMARY We present the case of a 44-year-old,healthy ... BACKGROUND Closed loop ileus caused by entrapment of bowel in a defect of the broad ligament is a rarity.Only a few cases have been reported in the literature.CASE SUMMARY We present the case of a 44-year-old,healthy patient with no prior history of abdominal surgery who developed a closed loop ileus due to an internal hernia secondary to a defect in the right broad ligament.She first presented to the emergency department with diarrhea and vomiting.As she had had no previous abdominal surgery,she was diagnosed with probable gastroenteritis and discharged.The patient subsequently returned to the emergency department due to a lack of improvement in her symptoms.Blood tests showed an elevated white blood cell count and a closed loop ileus was diagnosed on an abdominal computer tomography scan.Diagnostic laparoscopy revealed an internal hernia entrapped in a 2 cm large defect in the right broad ligament.The hernia was reduced and the ligament defect was closed using a running,barbed suture.CONCLUSION Bowel incarceration through an internal hernia may present with misleading symptoms and laparoscopy may reveal unexpected findings. 展开更多
关键词 broad ligament ILEUS Internal hernia LAPAROSCOPY Case report
下载PDF
A broad learning-based comprehensive defence against SSDP reflection attacks in IoTs
7
作者 Xin Liu Liang Zheng +3 位作者 Sumi Helal Weishan Zhang Chunfu Jia Jiehan Zhou 《Digital Communications and Networks》 SCIE CSCD 2023年第5期1180-1189,共10页
The proliferation of Internet of Things(IoT)rapidly increases the possiblities of Simple Service Discovery Protocol(SSDP)reflection attacks.Most DDoS attack defence strategies deploy only to a certain type of devices ... The proliferation of Internet of Things(IoT)rapidly increases the possiblities of Simple Service Discovery Protocol(SSDP)reflection attacks.Most DDoS attack defence strategies deploy only to a certain type of devices in the attack chain,and need to detect attacks in advance,and the detection of DDoS attacks often uses heavy algorithms consuming lots of computing resources.This paper proposes a comprehensive DDoS attack defence approach which combines broad learning and a set of defence strategies against SSDP attacks,called Broad Learning based Comprehensive Defence(BLCD).The defence strategies work along the attack chain,starting from attack sources to victims.It defends against attacks without detecting attacks or identifying the roles of IoT devices in SSDP reflection attacks.BLCD also detects suspicious traffic at bots,service providers and victims by using broad learning,and the detection results are used as the basis for automatically deploying defence strategies which can significantly reduce DDoS packets.For evaluations,we thoroughly analyze attack traffic when deploying BLCD to different defence locations.Experiments show that BLCD can reduce the number of packets received at the victim to 39 without affecting the standard SSDP service,and detect malicious packets with an accuracy of 99.99%. 展开更多
关键词 Denial-of-service DRDoS SSDP reflection Attack broad learning Traffic detection
下载PDF
Flexible broadband WS_(2)/Si optical position-sensitive detector with high sensitivity and fast speed
8
作者 Yunjie Liu Yupeng Wu +5 位作者 Fuhai Guo Yingming Liu Shirong Zhao Siqi Li Weizhuo Yu Lanzhong Hao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第6期1217-1224,共8页
Si-based optical position-sensitive detectors(PSDs)have stimulated the interest of researchers due to their wide range of practical applications.However,due to the rigidity and fragility of Si crystals,the application... Si-based optical position-sensitive detectors(PSDs)have stimulated the interest of researchers due to their wide range of practical applications.However,due to the rigidity and fragility of Si crystals,the applications of flexible PSDs have been limited.Therefore,we presented a flexible broadband PSD based on a WS_(2)/Si heterostructure for the first time.A scalable sputtering method was used to deposit WS_(2)thin films onto the etched ultrathin crystalline Si surface.The fabricated flexible PSD device has a broad spectral response in the wavelength range of 450-1350 nm,with a high position sensitivity of~539.8 mV·mm^(−1)and a fast response of 2.3μs,thanks to the strong light absorption,the built-in electrical field at the WS_(2)/Si interface,and facilitated transport.Furthermore,mechanical-bending tests revealed that after 200 mechanical-bending cycles,the WS_(2)/Si PSDs have excellent mechanical flexibility,stability,and durability,demonstrating the great potential in wearable PSDs with competitive performance. 展开更多
关键词 FLEXIBLE position-sensitive detectors WS^(2)heterostructure broad spectral response high sensitivity
下载PDF
Music Emotion Recognition Based on Feature Fusion Broad Learning Method
9
作者 郁进明 张晨光 海涵 《Journal of Donghua University(English Edition)》 CAS 2023年第3期343-350,共8页
With the rapid development in the field of artificial intelligence and natural language processing(NLP),research on music retrieval has gained importance.Music messages express emotional signals.The emotional classifi... With the rapid development in the field of artificial intelligence and natural language processing(NLP),research on music retrieval has gained importance.Music messages express emotional signals.The emotional classification of music can help in conveniently organizing and retrieving music.It is also the premise of using music for psychological intervention and physiological adjustment.A new chord-to-vector method was proposed,which converted the chord information of music into a chord vector of music and combined the weight of the Mel-frequency cepstral coefficient(MFCC) and residual phase(RP) with the feature fusion of a cochleogram.The music emotion recognition and classification training was carried out using the fusion of a convolution neural network and bidirectional long short-term memory(BiLSTM).In addition,based on the self-collected dataset,a comparison of the proposed model with other model structures was performed.The results show that the proposed method achieved a higher recognition accuracy compared with other models. 展开更多
关键词 music emotion recognition broad learning residual phase(RP) deep learning
下载PDF
Broadband and continuous wave pumped second-harmonic generation from microfiber coated with layered GaSe crystal
10
作者 Zhen Hao Biqiang Jiang +3 位作者 Yuxin Ma Ruixuan Yi Xuetao Gan Jianlin Zhao 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第9期59-68,共10页
The conversion-efficiency for second-harmonic(SH)in optical fibers is significantly limited by extremely weak second-order nonlinearity of fused silica,and pulse pump lasers with high peak power are widely employed.He... The conversion-efficiency for second-harmonic(SH)in optical fibers is significantly limited by extremely weak second-order nonlinearity of fused silica,and pulse pump lasers with high peak power are widely employed.Here,we propose a simple strategy to efficiently realize the broadband and continuous wave(CW)pumped SH,by transferring a crystalline GaSe coating onto a microfiber with phase-matching diameter.In the experiment,high efficiency up to 0.08%W-1mm-1 is reached for a C-band pump laser.The high enough efficiency not only guarantees SH at a single frequency pumped by a CW laser,but also multi-frequencies mixing supported by three CW light sources.Moreover,broadband SH spectrum is also achieved under the pump of a superluminescent light-emitting diode source with a 79.3 nm bandwidth.The proposed scheme provides a beneficial method to the enhancement of various nonlinear parameter processes,development of quasi-monochromatic or broadband CW light sources at new wavelength regions. 展开更多
关键词 nonlinear optics second-harmonic generation continuous wave pump high efficiency multi-frequencies mixing broad spectra MICROFIBERS gallium selenide
下载PDF
传统发酵乳品中产广谱细菌素乳酸菌选育 被引量:1
11
作者 刘彩云 麻和平 +3 位作者 张文齐 王洁 彭章普 邵建宁 《中国酿造》 CAS 北大核心 2024年第1期131-135,共5页
为选育产广谱细菌素乳酸菌,采用琼脂扩散法对甘肃牧区传统发酵乳品中分离纯化的96株乳酸菌进行了筛选,并确定产细菌素菌株,具有最佳抑菌效果的菌株经重离子束12C6+辐照诱变,再采用培养皿分区法进行6种指示菌广谱抑菌性能比较。结果表明... 为选育产广谱细菌素乳酸菌,采用琼脂扩散法对甘肃牧区传统发酵乳品中分离纯化的96株乳酸菌进行了筛选,并确定产细菌素菌株,具有最佳抑菌效果的菌株经重离子束12C6+辐照诱变,再采用培养皿分区法进行6种指示菌广谱抑菌性能比较。结果表明,琼脂扩散法筛选出抑菌效果最佳的产细菌素菌株Lp1,经辐照诱变得到98株突变菌,选育出对大肠埃希氏菌(Escherichia coli)、金黄色葡萄球菌(Staphylococcus aureus)、单核细胞增生李斯特氏菌(Listeria monocytogenes)、沙门氏菌(Salmonella)、志贺氏菌(Shigella)和克罗诺杆菌(Cronobacter)抑菌性能均明显优于出发菌株Lp1的5株突变株L088、L087、L063、L049、L010进行广谱抑菌试验,其中菌株L088和L063为广谱抑菌性能较好菌株,突变株L088对上述6种指示菌的抑菌扇环半径比出发菌株Lp1抑菌扇环半径分别提高47.81%、33.28%、22.97%、45.25%、21.39%、40.21%,突变株L063对上述6种指示菌的抑菌扇环半径比出发菌株Lp1抑菌扇环半径分别提高54.27%、29.18%、25.37%、58.03%、17.85%、42.13%。采用培养皿分区法可同时在1个培养皿中完成检测6种指示菌的抑菌试验,可高效筛选产广谱细菌素乳酸菌。 展开更多
关键词 乳酸菌 细菌素 广谱抑菌 抑菌试验
下载PDF
基于GA-BLS方法的手势识别研究 被引量:2
12
作者 杜义浩 曹添福 +1 位作者 范强 王孝冉 《计量学报》 CSCD 北大核心 2024年第1期121-127,共7页
为进一步提升人机交互领域中手势识别的精度和速度,探究肌肉疲劳对手势识别的影响规律,提出了改进的GA-BLS方法,利用遗传算法(genetic algorithms,GA)优化宽度学习(broad learning system,BLS)模型参数,并使用弹性网络回归改进传统的BL... 为进一步提升人机交互领域中手势识别的精度和速度,探究肌肉疲劳对手势识别的影响规律,提出了改进的GA-BLS方法,利用遗传算法(genetic algorithms,GA)优化宽度学习(broad learning system,BLS)模型参数,并使用弹性网络回归改进传统的BLS模型。利用所提模型对8种手势下的A型超声信号和肌电信号进行手势识别分析,并与SVM、KNN、RF、LDA等方法进行对比,以验证所研究方法的有效性;将长时间段下的A型超声信号和肌电信号切分成4个数据段,发现随着肌肉疲劳程度的增加,手势识别的准确率均呈现出明显下降的趋势,而且A型超声信号相较于肌电信号具有更好的抗疲劳特性。 展开更多
关键词 手势识别 生理信号 遗传算法 宽度学习 肌肉疲劳 弹性网络回归
下载PDF
温升作用下CRTSⅡ型板宽窄接缝受力及损伤分析
13
作者 刘笑凯 刘学毅 +1 位作者 肖杰灵 董佳佳 《西南交通大学学报》 EI CSCD 北大核心 2024年第2期273-280,共8页
为研究宽窄接缝在温升作用下的受力和损伤,根据混凝土塑性损伤理论和内聚力理论,建立考虑新旧混凝土界面的宽窄接缝细部的有限元模型;计算不同温升条件下的宽窄接缝应力和损伤因子,并分析宽窄接缝强度和窄接缝宽度的影响.研究结果表明:... 为研究宽窄接缝在温升作用下的受力和损伤,根据混凝土塑性损伤理论和内聚力理论,建立考虑新旧混凝土界面的宽窄接缝细部的有限元模型;计算不同温升条件下的宽窄接缝应力和损伤因子,并分析宽窄接缝强度和窄接缝宽度的影响.研究结果表明:窄接缝挤碎是一种渐变受压损伤,宽、窄接缝交界处断裂是一种脆性受拉损伤;与宽、窄接缝交界处断裂相比,窄接缝挤碎对结构受力影响更大;宽窄接缝尺寸不均匀导致宽、窄接缝交界处垂向受拉,这是宽窄接缝产生损伤的主要原因;提高宽窄接缝的混凝土强度可有效降低垂向拉应力和受拉损伤,但对纵向应力和受压损伤影响较小;为改善受力并降低损伤,建议宽窄接缝混凝土与轨道板等强,并且宽窄接缝上下等宽. 展开更多
关键词 无砟轨道 CRTSⅡ型板式轨道 宽窄接缝
下载PDF
基于门控宽度模型的结构监测数据预测
14
作者 王立新 王亚飞 +3 位作者 杨佳宇 李储军 汪珂 罗向龙 《科学技术与工程》 北大核心 2024年第18期7719-7725,共7页
随着信息技术的不断发展,机器学习在结构自动化监测中的应用逐渐增长。数据分析与预测作为结构自动化监测的重要一环,是保障结构安全的关键。针对目前结构监测数据预测方法未充分挖掘数据特征和运算时间冗长的问题,提出了一种基于门控... 随着信息技术的不断发展,机器学习在结构自动化监测中的应用逐渐增长。数据分析与预测作为结构自动化监测的重要一环,是保障结构安全的关键。针对目前结构监测数据预测方法未充分挖掘数据特征和运算时间冗长的问题,提出了一种基于门控宽度模型(gated broad learning system,G-BLS)监测数据预测模型。G-BLS在BLS特征节点增加遗忘门和循环反馈门机制,能够控制特征节点提取相关性高的信息。与深度模型相比,G-BLS模型网络结构简单,在保证预测精度的同时大大减少了模型训练时间。实测的地铁基坑沉降数据测试结果表明,G-BLS可有效实现预测监测数据的可靠性与实时性,是一种精准快速的结构监测数据预测方法。 展开更多
关键词 结构变形 数据预测 宽度学习 深度学习
下载PDF
数智技术赋能统战工作发展透视 被引量:1
15
作者 王飞 《西华大学学报(哲学社会科学版)》 2024年第2期23-33,共11页
数智技术与统战工作在价值理念和政治定位等层面具有高度契合性,前者可以满足后者信息化、智能化、精准化、动态化等发展需求,为后者高质量发展提供持续动能。数智技术能有效支撑和服务于统战工作、开拓统战工作数据应用新空间、激发统... 数智技术与统战工作在价值理念和政治定位等层面具有高度契合性,前者可以满足后者信息化、智能化、精准化、动态化等发展需求,为后者高质量发展提供持续动能。数智技术能有效支撑和服务于统战工作、开拓统战工作数据应用新空间、激发统战工作新活力。当前我国数智统战工作取得了一些进展,但也面临数字化平台和工具应用不足、数据共享和协同体系不完善以及数智化人才短缺和统战干部理念更新不足等问题。因此,未来数智统战应综合运用数智技术,通过构建面向统战对象的大数据智能分析平台、开发数智化统战工作工具、丰富宣传内容和形式,推动统战工作凝聚人心、汇聚力量;通过制定统一的数智统战顶层设计和规划、构建统一开放的统战云平台、完善数智安全保障体系,赋能大统战工作格局的构建;通过推进协商数智化体系构建、建立政协系统数智人才培训与考核机制、加大新技术在协商业务流程中的应用,深化协商民主。 展开更多
关键词 统战工作 大统战工作格局 协商民主 数智技术 数据共享 数据安全
下载PDF
不同叶面肥对稻茬蚕豆产量和品质的影响
16
作者 赵娜 薛冬 +5 位作者 姚梦楠 周瑶 周恩强 王永强 缪亚梅 王学军 《上海农业学报》 2024年第1期29-33,共5页
为探讨蚕豆高效栽培技术,研究了6种不同叶面肥对稻茬蚕豆产量和品质的影响。结果表明:与对照(CK)相比,赤·吲乙·芸苔(T1)、生根粉(T2)、含氨基酸水溶肥(T4)、含腐殖酸水溶肥(T5)、糖醇螯合硅肥(T6)处理的蚕豆株高均显著增加;T... 为探讨蚕豆高效栽培技术,研究了6种不同叶面肥对稻茬蚕豆产量和品质的影响。结果表明:与对照(CK)相比,赤·吲乙·芸苔(T1)、生根粉(T2)、含氨基酸水溶肥(T4)、含腐殖酸水溶肥(T5)、糖醇螯合硅肥(T6)处理的蚕豆株高均显著增加;T1、复硝酚钠(T3)、T4、T5处理的蚕豆始荚高显著增加;T1处理的蚕豆大分枝节数显著增加;T2、T4、T5处理的蚕豆籽粒显著增大,T5处理的蚕豆籽粒百粒重显著提高13.39%。从产量上看,T5处理的稻茬蚕豆荚和籽粒产量分别较CK显著增加63.96%和58.97%。从品质指标来看,T4处理的蚕豆籽粒蛋白质含量较CK显著增加8.33%;T2处理的籽粒脂肪含量较CK显著增加15.73%。合理喷施适宜的叶面肥有助于提高稻茬蚕豆产量和部分品质指标,可在稻茬蚕豆栽培技术中应用。 展开更多
关键词 叶面肥 稻茬蚕豆 产量 品质
下载PDF
蚕豆物性参数测定与离散元仿真参数标定
17
作者 文昌俊 徐云飞 +2 位作者 游达章 邵明颖 陈哲 《农机化研究》 北大核心 2024年第8期159-166,173,共9页
采用离散元法对蚕豆与收获机具间的相互作用进行数值仿真研究,实现对蚕豆收获机具关键部件相关参数的设计与优化,以提高研究效率、减少研究成本。为此,通过物理试验对蚕豆基本物性参数、接触力学参数和休止角进行测定,参考物理试验测定... 采用离散元法对蚕豆与收获机具间的相互作用进行数值仿真研究,实现对蚕豆收获机具关键部件相关参数的设计与优化,以提高研究效率、减少研究成本。为此,通过物理试验对蚕豆基本物性参数、接触力学参数和休止角进行测定,参考物理试验测定结果选取仿真试验参数取值范围。以仿真试验休止角为响应值,由Plackette-Burman(PB)试验得到显著影响休止角的试验参数(蚕豆-蚕豆静摩擦因数、蚕豆-钢板静摩擦因数、蚕豆-钢板滚动摩擦因数),并利用最陡爬坡试验在PB试验基础上得到显著参数的取值范围。采用Box-Behnken(BB)试验在休止角与显著参数之间建立二阶回归模型,以休止角物理试验测定值为目标值,对显著参数进行寻优,获得最优参数组合,即蚕豆-蚕豆静摩擦因数0.25、蚕豆-钢板静摩擦因数0.47、蚕豆-钢板滚动摩擦因数0.35。最后,通过T检验得到P>0.05,表明采用最优参数组合得到的休止角仿真值与实测值相差无几,验证了最优参数组合的可靠性。 展开更多
关键词 蚕豆 离散元 参数标定 优化
下载PDF
郑州市常绿灌木滞留颗粒物能力及季节差异
18
作者 贺丹 王翼飞 +5 位作者 原江琴 李朝梅 王晨旭 雷雅凯 刘艺平 李永华 《西北林学院学报》 CSCD 北大核心 2024年第3期257-265,共9页
选取郑州市12种常见常绿阔叶灌木为研究材料,运用3级滤膜法测定叶片对各粒径颗粒物(TSP、PM_(>10)、PM_(10)、PM_(2.5))的滞留量,并通过超景深显微镜和扫描电镜观察比较12种灌木的叶表面微形态结构,分析灌木叶片的滞尘能力、滞尘粒... 选取郑州市12种常见常绿阔叶灌木为研究材料,运用3级滤膜法测定叶片对各粒径颗粒物(TSP、PM_(>10)、PM_(10)、PM_(2.5))的滞留量,并通过超景深显微镜和扫描电镜观察比较12种灌木的叶表面微形态结构,分析灌木叶片的滞尘能力、滞尘粒度特征及季节差异。结果表明:1)不同植物的滞尘能力差异显著(P<0.05),火棘和夹竹桃滞留各粒径颗粒物的能力最强,洒金桃叶珊瑚和南天竹最弱。叶片滞留的颗粒物以PM_(>10)为主,其次为PM_(2.5),PM_(2.5~10)的占比最小,在2.52%~15.36%。2)各植物在滞尘粒度特征和滞尘量方面存在季节差异。植物对不同粒径颗粒物的滞留量总体呈现冬季大于春、夏、秋三季的规律,但对PM_(>10)、PM_(2.5)和PM_(2.5~10)的质量占比分别在冬春季、夏季和春季最高。3)叶表面微结构观察表明,叶尖和叶尾是滞留颗粒物的重要部位,而微结构如沟槽、凸起、绒毛、簇状结构等微形态结构则增强了植物的滞尘能力。电镜观察发现,有些植物叶表面具有菌丝,相关分析发现蜡质含量越多则菌丝越多,滞尘能力越强。滞尘树种的筛选应该综合考虑滞尘量、滞尘粒度及季节更替等因素,火棘和夹竹桃对各粒径颗粒物的滞留能力均较强,可以作为郑州市园林绿化中的首选树种。 展开更多
关键词 常绿阔叶灌木 滞留能力 粒度 季节差异 叶表微形态
下载PDF
离子改性对宽分子量分布聚丙烯黏弹性能影响
19
作者 徐耀辉 唐伊文 +1 位作者 郭鹏 吕明福 《中国塑料》 CAS CSCD 北大核心 2024年第1期7-13,共7页
宽分子量分布聚丙烯(BMWDPP)PP1经离子改性剂处理后得到PP4。通过凝胶渗透色谱(GPC)与平板旋转流变、拉伸流变和熔体强度测试研究了PP1和PP4的分子结构与流变性能的变化。离子改性过程中的自由基诱发PP降解会降低BMWDPP的分子量大小及... 宽分子量分布聚丙烯(BMWDPP)PP1经离子改性剂处理后得到PP4。通过凝胶渗透色谱(GPC)与平板旋转流变、拉伸流变和熔体强度测试研究了PP1和PP4的分子结构与流变性能的变化。离子改性过程中的自由基诱发PP降解会降低BMWDPP的分子量大小及多分散性;虽未形成真正的长支链结构,但由于接枝在PP分子链上的金属盐之间靠离子相互作用造成“类长支链”效果,PP4可产生拉伸应变硬化现象;PP4因大分子量组分的降解削弱缠结及小分子量组分的降解增强塑化,导致黏弹性低于PP1。拉伸应变硬化对熔体强度增高的影响强于分子量降低对熔体强度削弱的影响,故PP4的熔体强度在不同的温度下皆高于PP1;在低温下呈现线形大分子量分子链PP特点,而在高温下呈现长支链PP特点。 展开更多
关键词 宽分子量分布聚丙烯 离子改性 黏弹性 拉伸应变硬化 熔体强度
下载PDF
勺轮式蚕豆排种器设计与排种性能研究
20
作者 冯锐 雷雪梅 +3 位作者 李林鑫 赖永江 粟超 陶丹 《中国农机化学报》 北大核心 2024年第7期15-21,共7页
为提升蚕豆机械化播种率,提出一种结构简单的勺轮式蚕豆排种器,分析不同排种转速与种子类型对排种性能的影响。首先,介绍勺轮式排种器结构与工作原理,统计分析蚕豆种子外形尺寸并划分为三类(小粒、中粒、大粒),设计蚕豆种子排种勺结构,... 为提升蚕豆机械化播种率,提出一种结构简单的勺轮式蚕豆排种器,分析不同排种转速与种子类型对排种性能的影响。首先,介绍勺轮式排种器结构与工作原理,统计分析蚕豆种子外形尺寸并划分为三类(小粒、中粒、大粒),设计蚕豆种子排种勺结构,理论分析排种器取种过程、清种过程与传种过程;然后,利用EDEM软件仿真排种器工作性能,建立排种器与三类蚕豆种子的仿真模型;最后,以合格指数、重播指数、漏播指数为排种性能评价标准,开展台架试验,验证勺轮式蚕豆排种器的可行性。结果表明:仿真环境下,排种器内蚕豆种子实际充种线的水平倾角与排种转速呈正相关。排种器适宜排种转速为10 r/min,中粒种子排种性能指标最优,其播种合格指数为90.3%,重播指数为6.9%,漏播指数为2.8%。当排种转速为10 r/min时,仿真试验的综合排种性能为:合格指数89.5%,重播指数6.25%,漏播指数4.25%;台架试验的综合排种性能为:合格指数89.2%、重播指数7.1%、漏播指数3.7%,与仿真试验结果基本一致,满足蚕豆播种要求,验证勺轮式蚕豆排种器的可行性。 展开更多
关键词 蚕豆 勺轮式排种器 EDEM仿真 排种性能
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部