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关注免疫检查点抑制剂发生irAE后免疫治疗再挑战
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作者 张东 王鹏 《中华保健医学杂志》 2024年第2期129-132,共4页
免疫检查点抑制剂(immune-checkpoint inhibitors,ICIs)是近年来肿瘤学领域最重要的突破之一,为不同类型的实体瘤治疗提供了新的范式。ICIs通过阻断免疫内在下调因子,如细胞毒性T淋巴细胞抗原4(CTLA-4)和程序性细胞死亡1(PD-1)或其配体... 免疫检查点抑制剂(immune-checkpoint inhibitors,ICIs)是近年来肿瘤学领域最重要的突破之一,为不同类型的实体瘤治疗提供了新的范式。ICIs通过阻断免疫内在下调因子,如细胞毒性T淋巴细胞抗原4(CTLA-4)和程序性细胞死亡1(PD-1)或其配体程序性细胞死亡配体1(PD-L1),增加抗肿瘤免疫力[1]。然而,由于免疫应答增强和免疫系统失衡,患者可能会发生免疫相关不良事件(immune-related adverse events,irAE)。 展开更多
关键词 免疫检查点抑制剂(immune-checkpoint inhibitors ICIs) 免疫相关不良事件(immune-related adverse events iraE) 免疫治疗再挑战(immune-checkpoint inhibitors rechallenge)
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Study of Complex Nitrogen and Oxygen-bearing Molecules toward the High-mass Protostar IRAS 18089–1732
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作者 Arijit Manna Sabyasachi Pal +1 位作者 Tapas Baug Sougata Mondal 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期81-93,共13页
The observation of oxygen(O)-and nitrogen(N)-bearing molecules gives an idea about the complex prebiotic chemistry in the interstellar medium.Recent millimeter and submillimeter wavelength observations have shown the ... The observation of oxygen(O)-and nitrogen(N)-bearing molecules gives an idea about the complex prebiotic chemistry in the interstellar medium.Recent millimeter and submillimeter wavelength observations have shown the presence of complex O-and N-bearing molecules in the star formation regions.So,the investigation of those molecules is crucial to understanding the chemical complexity in the star-forming regions.In this article,we present the identification of the rotational emission lines of N-bearing molecules ethyl cyanide(C_(2)H_(5)CN)and cyanoacetylene(HC_(3)N),and O-bearing molecule methyl formate(CH_(3)OCHO)toward high-mass protostar IRAS18089–1732 using the Atacama Compact Array.We also detected the emission lines of both the N-and O-bearing molecule formamide(NH_(2)CHO)in the envelope of IRAS 18089–1732.We have detected the v=0 and 1 state rotational emission lines of CH_(3)OCHO.We also detected the two vibrationally excited states of HC_(3)N(v7=1 and v7=2).The estimated fractional abundances of C_(2)H_(5)CN,HC_(3)N(v7=1),HC_(3)N(v7=2),and NH_(2)CHO toward IRAS 18089–1732 are(1.40±0.5)×10^(-10),(7.5±0.7)×10^(-11),(3.1±0.4)×10^(-11),and(6.25±0.82)×10^(-11)respectively.Similarly,the estimated fractional abundances of CH_(3)OCHO(v=0)and CH_(3)OCHO(v=1)are(1.90±0.9)×10^(-9)and(8.90±0.8)×10^(-10),respectively.We also created the integrated emission maps of the detected molecules,and the observed molecules may have originated from the extended envelope of the protostar.We show that C_(2)H_(5)CNand HC_(3)N are most probably formed via the subsequential hydrogenation of the CH_(2)CHCNand the reaction between C_(2)H_(2)and CN on the grain surface of IRAS 18089–1732.We found that NH_(2)CHO is probably produced due to the reaction between NH_(2)and H_(2)CO in the gas phase.Similarly,CH_(3)OCHO is possibly created via the reaction between radical CH_(3)O and radical HCO on the grain surface of IRAS 18089–1732. 展开更多
关键词 ISM:individual objects(ira 18089-1732)(except) ISM:abundances ISM:kinematics and dynamics stars:formation ASTROCHEMISTRY
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A Simple and Effective Surface Defect Detection Method of Power Line Insulators for Difficult Small Objects
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作者 Xiao Lu Chengling Jiang +2 位作者 Zhoujun Ma Haitao Li Yuexin Liu 《Computers, Materials & Continua》 SCIE EI 2024年第4期373-390,共18页
Insulator defect detection plays a vital role in maintaining the secure operation of power systems.To address the issues of the difficulty of detecting small objects and missing objects due to the small scale,variable... Insulator defect detection plays a vital role in maintaining the secure operation of power systems.To address the issues of the difficulty of detecting small objects and missing objects due to the small scale,variable scale,and fuzzy edge morphology of insulator defects,we construct an insulator dataset with 1600 samples containing flashovers and breakages.Then a simple and effective surface defect detection method of power line insulators for difficult small objects is proposed.Firstly,a high-resolution featuremap is introduced and a small object prediction layer is added so that the model can detect tiny objects.Secondly,a simplified adaptive spatial feature fusion(SASFF)module is introduced to perform cross-scale spatial fusion to improve adaptability to variable multi-scale features.Finally,we propose an enhanced deformable attention mechanism(EDAM)module.By integrating a gating activation function,the model is further inspired to learn a small number of critical sampling points near reference points.And the module can improve the perception of object morphology.The experimental results indicate that concerning the dataset of flashover and breakage defects,this method improves the performance of YOLOv5,YOLOv7,and YOLOv8.In practical application,it can simply and effectively improve the precision of power line insulator defect detection and reduce missing detection for difficult small objects. 展开更多
关键词 Insulator defect detection small object power line deformable attention mechanism
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A Novel Tensor Decomposition-Based Efficient Detector for Low-Altitude Aerial Objects With Knowledge Distillation Scheme
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作者 Nianyin Zeng Xinyu Li +2 位作者 Peishu Wu Han Li Xin Luo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期487-501,共15页
Unmanned aerial vehicles(UAVs) have gained significant attention in practical applications, especially the low-altitude aerial(LAA) object detection imposes stringent requirements on recognition accuracy and computati... Unmanned aerial vehicles(UAVs) have gained significant attention in practical applications, especially the low-altitude aerial(LAA) object detection imposes stringent requirements on recognition accuracy and computational resources. In this paper, the LAA images-oriented tensor decomposition and knowledge distillation-based network(TDKD-Net) is proposed,where the TT-format TD(tensor decomposition) and equalweighted response-based KD(knowledge distillation) methods are designed to minimize redundant parameters while ensuring comparable performance. Moreover, some robust network structures are developed, including the small object detection head and the dual-domain attention mechanism, which enable the model to leverage the learned knowledge from small-scale targets and selectively focus on salient features. Considering the imbalance of bounding box regression samples and the inaccuracy of regression geometric factors, the focal and efficient IoU(intersection of union) loss with optimal transport assignment(F-EIoU-OTA)mechanism is proposed to improve the detection accuracy. The proposed TDKD-Net is comprehensively evaluated through extensive experiments, and the results have demonstrated the effectiveness and superiority of the developed methods in comparison to other advanced detection algorithms, which also present high generalization and strong robustness. As a resource-efficient precise network, the complex detection of small and occluded LAA objects is also well addressed by TDKD-Net, which provides useful insights on handling imbalanced issues and realizing domain adaptation. 展开更多
关键词 Attention mechanism knowledge distillation(KD) object detection tensor decomposition(TD) unmanned aerial vehicles(UAVs)
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Management of Penetrating Cranioencephalic Trauma Caused by Sharp Metal Objects—Therapeutic and Evolutionary Aspects: 12 Cases at the Renaissance University Hospital in N’Djamena
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作者 Goumantar Félicien Toudjingar Li-Iyane Olivier Ouambi +3 位作者 Yannick Canton Kessely Donal Djasdé Mahouli Fata Vounki Momar Codé Ba 《Open Journal of Modern Neurosurgery》 2024年第2期170-178,共9页
Introduction: Cranioencephalic trauma caused by bladed weapons is rare, and that caused by sharp objects is exceptional. The aim of our study was to describe the clinical, therapeutic and evolutionary aspects. Materia... Introduction: Cranioencephalic trauma caused by bladed weapons is rare, and that caused by sharp objects is exceptional. The aim of our study was to describe the clinical, therapeutic and evolutionary aspects. Materials and method: This was a descriptive and analytical study over a 48-month period at CHU la Renaissance from January 1, 2018 to December 31, 2021, concerning patients admitted for penetrating cranioencephalic trauma by pointed object. Results: Twelve cases, all male, of penetrating cranioencephalic sharp-force trauma were identified. The mean age was 34 ± 7 years, with extremes of 11 and 60 years. Farmers and herders accounted for 31% and 25% of cases respectively. The average admission time was 47 hours. Brawls were the circumstances of occurrence in 81.2% of cases. Knives (33%), arrows (25%) and iron bars (16.6%) were the objects used. Altered consciousness was present in 43.8% of cases, and focal deficit in 50%. Scannographic lesions were fracture and/or embarrhment (12 cases), intra-parenchymal haematomas (6 cases) and presence of object in place (4 cases). Surgery was performed in 11 patients. Postoperative outcome was favorable in 9 patients. After 12 months, 2 patients were declared unfit. Conclusion: Penetrating head injuries caused by sharp objects are common in Chad. Urgent surgery can prevent disabling after-effects. 展开更多
关键词 Penetrating Trauma SKULL Encephalon Sharp Object Surgery Patient Outcome
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Patterns of Interactions of the Complex City System:Emotional Urban Objects as Triggering Agents-A Secondary Publication
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作者 O.A.Gonzalez Liliana Beatriz Sosa Compeán 《Journal of World Architecture》 2024年第1期45-53,共9页
This article presents an analysis of the patterns of interactions resulting from the positive and negative emotional events that occur in cities,considering them as complex systems.It explores,from the imaginaries,how... This article presents an analysis of the patterns of interactions resulting from the positive and negative emotional events that occur in cities,considering them as complex systems.It explores,from the imaginaries,how certain urban objects can act as emotional agents and how these events affect the urban system as a whole.An adaptive complex systems perspective is used to analyze these patterns.The results show patterns in the processes and dynamics that occur in cities based on the objects that affect the emotions of the people who live there.These patterns depend on the characteristics of the emotional charge of urban objects,but they can be generalized in the following process:(1)immediate reaction by some individuals;(2)emotions are generated at the individual level which begins to generalize,permuting to a collective emotion;(3)a process of reflection is detonated in some individuals from the reading of collective emotions;(4)integration/significance in the community both at the individual and collective level,on the concepts,roles and/or functions that give rise to the process in the system.Therefore,it is clear that emotions play a significant role in the development of cities and these aspects should be considered in the design strategies of all kinds of projects for the city.Future extensions of this work could include a deeper analysis of specific emotional events in urban environments,as well as possible implications for urban policy and decision making. 展开更多
关键词 Emotional events Urban objects Complex adaptive systems Adaptive complex systems City
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第三支柱个人养老金制度的税收优惠模式分析——以美国IRA为例
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作者 马源 《辽宁大学学报(哲学社会科学版)》 2023年第2期83-93,共11页
税收优惠模式是第三支柱个人养老金制度政府激励措施中的重要内容。文章通过分析EET和TEE两种税收优惠模式,探讨两者的内在特征并进行比较,发现两者在总体账户积累和税收让利等方面没有明显区别,并以美国IRA制度为例,分析其制度特征和... 税收优惠模式是第三支柱个人养老金制度政府激励措施中的重要内容。文章通过分析EET和TEE两种税收优惠模式,探讨两者的内在特征并进行比较,发现两者在总体账户积累和税收让利等方面没有明显区别,并以美国IRA制度为例,分析其制度特征和实施效果。制度中的传统IRA和罗斯IRA分别体现了两种税收优惠模式,二者的不同主要体现在账户缴费和资金领取的方式、税率变动和个人的参保行为及心理预期等方面。文章分析发现税收优惠政策在个人的缴费、投资及领取阶段会产生不同的激励效应,并基于此就激励我国第三支柱个人养老金制度的有效参与提出了建议。 展开更多
关键词 税收优惠模式 传统ira 罗斯ira
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Numerical Investigations on Harbor Oscillations Induced by Falling Objects 被引量:1
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作者 GAO Jun-liang BI Wen-jing +1 位作者 ZHANG Jian ZANG Jun 《China Ocean Engineering》 SCIE EI CSCD 2023年第3期458-470,共13页
In this paper,the open-sourced computational fluid dynamics software,OpenFOAM~?,is used to study the fluctuation phenomenon of the water body inside a horizontally one-dimensional enclosed harbor basin with constant w... In this paper,the open-sourced computational fluid dynamics software,OpenFOAM~?,is used to study the fluctuation phenomenon of the water body inside a horizontally one-dimensional enclosed harbor basin with constant water depth triggered by falling wedges with various horizontal falling positions,initial falling velocities and masses.Based on both Fourier transfo rm analysis and wavelet spectrum analysis for the time series of the free surface elevations inside the harbor basin,it is found for the first time that the wedge falling inside the harbor can directly trigger harbor resonance.The influences of the three factors(including the horizontal falling position,the initial falling velocity,and the mass)on the response amplitudes of the lowest three resonant modes are also investigated.The results show that when the wedge falls on one of the nodal points of a resonant mode,the mode would be remarkably suppressed.Conversely,when the wedge falls on one of the anti-nodal points of a resonant mode,the mode would be evidently triggered.The initial falling velocity of the wedge mainly has a remarkable effect on the response amplitude of the most significant mode,and the latter shows a gradual increase trend with the increase of the former.While for the other two less significant modes,their response amplitudes fluctuate around certain constant values as the initial falling velocity rises.In general,the response amplitudes of all the lowest three modes are shown to gradually increase with the mass of the wedge. 展开更多
关键词 harbor oscillations SEICHES falling objects resonant mode response amplitude
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LVEF对STEMI合并non-IRA CTO患者PCI术预后的影响 被引量:1
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作者 李鹏鹏 吕哲 +1 位作者 冯怡 代传忠 《中南医学科学杂志》 CAS 2023年第3期433-436,共4页
目的 探讨非梗死相关动脉(non-IRA)慢性完全闭塞(CTO)合并ST段抬高心肌梗死(STEMI)患者行经皮冠状动脉介入治疗(PCI)术的预后与左心室射血分数(LVEF)之间的关系。方法 选取STEMI患者130例,根据LVEF水平分为LVEF降低组和LVEF保留组;根据... 目的 探讨非梗死相关动脉(non-IRA)慢性完全闭塞(CTO)合并ST段抬高心肌梗死(STEMI)患者行经皮冠状动脉介入治疗(PCI)术的预后与左心室射血分数(LVEF)之间的关系。方法 选取STEMI患者130例,根据LVEF水平分为LVEF降低组和LVEF保留组;根据是否合并CTO分为CTO亚组和无CTO亚组。随访1年,比较两组患者的全因死亡和主要心血管不良事件(MACE)。结果 与无CTO亚组比较,LVEF降低患者CTO亚组有更高全因死亡率和MACE发生率;而LVEF保留患者CTO亚组与无CTO亚组之间上述指标差异无显著性。在LVEF降低患者中,non-IRA CTO是全因死亡和MACE的独立预测因子。结论 non-IRA CTO是LVEF降低STEMI患者全因死亡和MACE的独立预测因子。 展开更多
关键词 STEMI non-ira CTO LVEF 急性心肌梗死
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基于FME Objects的空间数据格式转换方法研究
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作者 周飞 《经纬天地》 2023年第6期78-81,87,共5页
地理信息数据广泛应用于大测绘、自然资源、建设规划等行业领域的信息分析与存储。因其数据叠加分析与跨专业融合学习的需要,满足数据的定向需求与统一性。本文基于FME Objects的引用库,运用C#语言研究了如何精确、完整实现数据格式转... 地理信息数据广泛应用于大测绘、自然资源、建设规划等行业领域的信息分析与存储。因其数据叠加分析与跨专业融合学习的需要,满足数据的定向需求与统一性。本文基于FME Objects的引用库,运用C#语言研究了如何精确、完整实现数据格式转换的程序方法,探寻了含非图形属性文件的转换函数表达方式,解析了程序实现的基础结构。经过诸多数据的转换验证,此系统能够提高数据格式的转换效率且能保证图形要素与属性的完整性,并可生成全面的转换日志与简易的质检文本,为各行业地理信息数据的统一整理提供便利。 展开更多
关键词 FME objects C# 程序解析 带属性数据转换
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Optimizing Storage for Energy Conservation in Tracking Wireless Sensor Network Objects
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作者 Vineet Sharma Mohammad Zubair Khan +2 位作者 Shivani Batra Abdullah Alsaeedi Prakash Srivastava 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1211-1231,共21页
The amount of needed control messages in wireless sensor networks(WSN)is affected by the storage strategy of detected events.Because broadcasting superfluous control messages consumes excess energy,the network lifespa... The amount of needed control messages in wireless sensor networks(WSN)is affected by the storage strategy of detected events.Because broadcasting superfluous control messages consumes excess energy,the network lifespan can be extended if the quantity of control messages is decreased.In this study,an optimized storage technique having low control overhead for tracking the objects in WSN is introduced.The basic concept is to retain observed events in internal memory and preserve the relationship between sensed information and sensor nodes using a novel inexpensive data structure entitled Ordered Binary Linked List(OBLL).Whenever an object passes over the sensor area,the recognizing sensor can immediately produce an OBLL along the object’s route.To retrieve the entire information,the OBLL can be traversed with logarithmic complexity which is much less than the traversing complexity of existing linked list structures.Performance evaluation and simulations were carried out to ensure that the suggested technique minimizes the number of messages and thus saving energy and extending the network life. 展开更多
关键词 Energy conservation linked list object tracking wireless sensor networks
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Application of 3D Scanned Big Data of Large-scale Cultural Heritage Objects Based on Noise-robust Transparent Visualization
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作者 Tanaka Satoshi 《系统仿真学报》 CAS CSCD 北大核心 2023年第8期1635-1650,共16页
Three-dimensional(3D) scanning technology has undergone remarkable developments in recent years.Data acquired by 3D scanning have the form of 3D point clouds.The 3D scanned point clouds have data sizes that can be con... Three-dimensional(3D) scanning technology has undergone remarkable developments in recent years.Data acquired by 3D scanning have the form of 3D point clouds.The 3D scanned point clouds have data sizes that can be considered big data.They also contain measurement noise inherent in measurement data.These properties of 3D scanned point clouds make many traditional CG/visualization techniques difficult.This paper reviewed our recent achievements in developing varieties of high-quality visualizations suitable for the visual analysis of 3D scanned point clouds.We demonstrated the effectiveness of the method by applying the visualizations to various cultural heritage objects.The main visualization targets used in this paper are the floats in the Gion Festival in Kyoto(the float parade is on the UNESCO Intangible Cultural Heritage List) and Borobudur Temple in Indonesia(a UNESCO World Heritage Site). 展开更多
关键词 3D scanning point cloud transparent visualization noise transparentization cultural heritage object
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New Fragile Watermarking Technique to Identify Inserted Video Objects Using H.264 and Color Features
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作者 Raheem Ogla Eman Shakar Mahmood +1 位作者 Rasha I.Ahmed Abdul Monem S.Rahma 《Computers, Materials & Continua》 SCIE EI 2023年第9期3075-3096,共22页
The transmission of video content over a network raises various issues relating to copyright authenticity,ethics,legality,and privacy.The protection of copyrighted video content is a significant issue in the video ind... The transmission of video content over a network raises various issues relating to copyright authenticity,ethics,legality,and privacy.The protection of copyrighted video content is a significant issue in the video industry,and it is essential to find effective solutions to prevent tampering and modification of digital video content during its transmission through digital media.However,there are stillmany unresolved challenges.This paper aims to address those challenges by proposing a new technique for detectingmoving objects in digital videos,which can help prove the credibility of video content by detecting any fake objects inserted by hackers.The proposed technique involves using two methods,the H.264 and the extraction color features methods,to embed and extract watermarks in video frames.The study tested the performance of the system against various attacks and found it to be robust.The evaluation was done using different metrics such as Peak-Signal-to-Noise Ratio(PSNR),Mean Squared Error(MSE),Structural Similarity Index Measure(SSIM),Bit Correction Ratio(BCR),and Normalized Correlation.The accuracy of identifying moving objects was high,ranging from 96.3%to 98.7%.The system was also able to embed a fragile watermark with a success rate of over 93.65%and had an average capacity of hiding of 78.67.The reconstructed video frames had high quality with a PSNR of at least 65.45 dB and SSIMof over 0.97,making them imperceptible to the human eye.The system also had an acceptable average time difference(T=1.227/s)compared with other state-of-the-art methods. 展开更多
关键词 Video watermarking fragile digital watermark copyright protection moving objects color image features H.264
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图像引导和点云空间约束的公路洒落物检测定位方法 被引量:1
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作者 蔡怀宇 杨朝乾 +2 位作者 崔子扬 汪毅 陈晓冬 《光电工程》 CAS CSCD 北大核心 2024年第3期129-141,共13页
公路洒落物是影响交通安全的重要因素之一,为了解决中小尺度公路洒落物检测中的漏检、误检以及难以定位等问题,本文提出了一种图像引导和点云空间约束的公路洒落物检测定位方法。该方法使用改进的YOLOv7-OD网络处理图像数据获取二维目... 公路洒落物是影响交通安全的重要因素之一,为了解决中小尺度公路洒落物检测中的漏检、误检以及难以定位等问题,本文提出了一种图像引导和点云空间约束的公路洒落物检测定位方法。该方法使用改进的YOLOv7-OD网络处理图像数据获取二维目标预测框信息,将目标预测框投影到激光雷达坐标系下得到锥形感兴趣区域(region of interest,ROI)。在ROI区域内的点云空间约束下,联合点云聚类和点云生成算法获得不同尺度的洒落物在三维空间中的检测定位结果。实验表明:改进的YOLOv7-OD网络在中尺度目标上的召回率和平均精度分别为85.4%和82.0%,相比YOLOv7网络分别提升6.6和8.0个百分点;在小尺度目标上的召回率和平均精度分别为66.8%和57.3%,均提升5.3个百分点;洒落物定位方面,对于距离检测车辆30~40 m处的目标,深度定位误差为0.19 m,角度定位误差为0.082°,实现了多尺度公路洒落物的检测和定位。 展开更多
关键词 公路洒落物 图像 激光雷达点云 目标检测
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一株米醋源植物乳杆菌发酵液对伊拉商品兔生产性能及肉品质的影响
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作者 马勇 慕永利 李向果 《中国饲料》 北大核心 2024年第2期14-17,共4页
文章旨在研究饮水中添加植物乳杆菌发酵液MC090对伊拉商品兔生长性能、屠宰性能和肉品质的影响。试验选取同批次且健康度良好的32日龄兔216只,随机分为2组(对照组和试验组),每组3个重复,每个重复36只。试验组饮水中添加植物乳杆菌MC090... 文章旨在研究饮水中添加植物乳杆菌发酵液MC090对伊拉商品兔生长性能、屠宰性能和肉品质的影响。试验选取同批次且健康度良好的32日龄兔216只,随机分为2组(对照组和试验组),每组3个重复,每个重复36只。试验组饮水中添加植物乳杆菌MC090发酵液5mL/L,分早中晚3次添加;对照组饮用自来水;试验为期23d。结果表明,(1)与对照组相比,试验组平均日增重有所增加,料肉比、死淘率均有所下降,但差异不显著(P>0.05);(2)与对照组相比,试验组空肠绒毛高度和V/C显著提高(P<0.05);(3)与对照组相比,试验组盲肠食糜pH,食糜总菌数和大肠杆菌数差异均不显著(P>0.05),乳酸杆菌数差异显著(P<0.05);(4)与对照组相比,试验组全净膛重、全净膛率、半净膛重、半净膛率,肌肉pH_(45min)、pH_(24h)、滴水损失率、L^(*)值、a^(*)值均无显著差异(P>0.05),剪切力和b^(*)值差异均显著(P<0.05)。综上所述,植物乳杆菌MC090发酵液可提升伊拉兔小肠绒毛高度,改善肠道健康度,促进兔生长,降低死淘率,降低料重比,提升生产效益。 展开更多
关键词 植物乳杆菌 伊拉商品兔 生产性能 肉品质
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饲粮中葛藤不同添加量对肉兔养分表观消化率、胃肠道发育及消化酶活性的影响
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作者 高承芳 桑雷 +3 位作者 孙世坤 陈冬金 王锦祥 谢喜平 《草业学报》 CSCD 北大核心 2024年第4期199-209,共11页
为探讨葛藤在肉兔饲粮中的应用效果,开展葛藤的常规营养成分分析,选取35±2日龄体重(0.88±0.13 kg)相近的断奶伊拉兔肉兔200只,随机分成4组,每组5个重复,每个重复10只,分别饲喂添加0(对照组)、15%、25%、35%葛藤的试验饲粮。... 为探讨葛藤在肉兔饲粮中的应用效果,开展葛藤的常规营养成分分析,选取35±2日龄体重(0.88±0.13 kg)相近的断奶伊拉兔肉兔200只,随机分成4组,每组5个重复,每个重复10只,分别饲喂添加0(对照组)、15%、25%、35%葛藤的试验饲粮。预试期7 d,正试期42 d。于正试期第36天开始进行为期7 d的消化代谢试验,分析肉兔养分表观消化率,试验结束后测定分析肉兔盲肠消化酶活性及胃肠道的变化。结果显示,饲粮中添加不同量的葛藤:1)提高了各处理组肉兔对饲粮中干物质、粗蛋白、粗纤维、中性洗涤纤维、酸性洗涤纤维、酸性木质素、粗脂肪和半乳糖醛酸的表观消化率,35%葛藤组表观消化率最高,显著高于15%葛藤组与对照组(P<0.05)。2)提高了肉兔盲肠中纤维素酶、半纤维素酶与果胶酶活性,15%葛藤组酶活性最高,显著高于对照组(P<0.05)。3)对肉兔胃及小肠的相对长度无显著影响(P>0.05),但显著提高了盲肠相对长度和重量、胃相对重量与小肠相对重量,25%与35%葛藤组显著高于对照组(P<0.05)。4)提高了肉兔空肠、回肠与十二指肠的绒毛长度、绒毛长度/隐窝深度比值(V/C)和黏膜层厚度,降低了隐窝深度值,35%葛藤组肉兔回肠、十二指肠的绒毛长度显著高于对照组(P<0.05),空肠、回肠的隐窝深度低于对照组,空肠、回肠的V/C显著高于对照组(P<0.05)。因此,生长肉兔饲粮中最适宜的葛藤添加量为35%。 展开更多
关键词 伊拉兔 葛藤 养分表观消化率 胃肠道发育 消化酶活性
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基于改进YOLOX与多级数据关联的行人多目标跟踪算法研究 被引量:2
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作者 韩锟 彭晶莹 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第1期94-105,共12页
目标跟踪是计算机视觉领域的基本问题,行人多目标跟踪在智能监控、智慧交通等多个领域有着广泛的应用前景。然而实际跟踪场景中存在频繁遮挡、尺度变化等情况,给多目标跟踪算法带来了极大的挑战。为了进一步提升跟踪精度,在DeepSORT的... 目标跟踪是计算机视觉领域的基本问题,行人多目标跟踪在智能监控、智慧交通等多个领域有着广泛的应用前景。然而实际跟踪场景中存在频繁遮挡、尺度变化等情况,给多目标跟踪算法带来了极大的挑战。为了进一步提升跟踪精度,在DeepSORT的基础上,提出一种基于改进YOLOX与多级数据关联的行人多目标跟踪算法。对于检测器,为了增强网络的特征表达能力,提高检测精度,在YOLOX骨架网络与颈部网络分别引入ECA通道注意力模块与ASFF自适应特征融合模块。对于身份识别特征,为了减少数据关联步骤的错误匹配数量,提高跟踪效率,使用轻量的OSNet重识别网络与NSA卡尔曼滤波获取目标特征。对于数据关联,为了减少身份切换次数,避免目标丢失,将检测与跟踪都进行分类处理,使用不同的相似性计算方法,实现基于检测置信度与轨迹状态的多级数据关联。实验结果表明:与改进前YOLOX与DeepSORT简单结合的算法相比,在YOLOX中引入ECA模块与ASFF模块使误检数量大幅降低,使用YOLOX-s模型时降幅可达17%;结合OSNet模型与NSA卡尔曼滤波的特征提取方法能提高跟踪稳定性,IDF1指标提高0.77%,IDSW减少947;基于检测置信度与轨迹状态的多级数据关联算法可以明显改善跟踪性能,MOTA指标提升3.36%。算法最终在MOT17与MOT20测试集上的MOTA达80.4%与77.7%,IDF1达78.4%与76.7%。提出的行人多目标跟踪方法相较于其他先进算法在跟踪精度与跟踪速度上达到更好的平衡,可为工业上在线行人多目标跟踪应用提供参考。 展开更多
关键词 多目标跟踪 目标检测 注意力机制 数据关联 计算机视觉
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CNN-Transformer特征融合多目标跟踪算法 被引量:1
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作者 张英俊 白小辉 谢斌红 《计算机工程与应用》 CSCD 北大核心 2024年第2期180-190,共11页
在卷积神经网络(CNN)中,卷积运算能高效地提取目标的局部特征,却难以捕获全局表示;而在视觉Transformer中,注意力机制可以捕获长距离的特征依赖,但会忽略局部特征细节。针对以上问题,提出一种基于CNN-Transformer双分支主干网络进行特... 在卷积神经网络(CNN)中,卷积运算能高效地提取目标的局部特征,却难以捕获全局表示;而在视觉Transformer中,注意力机制可以捕获长距离的特征依赖,但会忽略局部特征细节。针对以上问题,提出一种基于CNN-Transformer双分支主干网络进行特征提取和融合的多目标跟踪算法CTMOT(CNN-transformer multi-object tracking)。使用基于CNN和Transformer双分支并行的主干网络分别提取图像的局部和全局特征。使用双向桥接模块(two-way braidge module,TBM)对两种特征进行充分融合。将融合后的特征输入两组并行的解码器进行处理。将解码器输出的检测框和跟踪框进行匹配,完成多目标跟踪任务。在多目标跟踪数据集MOT17、MOT20、KITTI以及UADETRAC上进行评估,CTMOT算法的MOTP和IDs指标在四个数据集上均达到了SOTA效果,MOTA指标分别达到了76.4%、66.3%、92.36%和88.57%,在MOT数据集上与SOTA方法效果相当,在KITTI数据集上达到SOTA效果。由于同时完成目标检测和关联,能够端到端进行目标跟踪,跟踪速度可达35 FPS,表明CTMOT算法在跟踪的实时性和准确性上达到了较好的平衡,具有较大潜力。 展开更多
关键词 多目标跟踪 TRANSFORMER 特征融合
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基于YOLO v8n-seg和改进Strongsort的多目标小鼠跟踪方法 被引量:2
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作者 梁秀英 贾学镇 +3 位作者 何磊 王翔宇 刘岩 杨万能 《农业机械学报》 EI CAS CSCD 北大核心 2024年第2期295-305,345,共12页
多目标小鼠跟踪是小鼠行为分析的基本任务,是研究社交行为的重要方法。针对传统小鼠跟踪方法存在只能跟踪单只小鼠以及对多目标小鼠跟踪需要对小鼠进行标记从而影响小鼠行为等问题,提出了一种基于实例分割网络YOLO v8n-seg和改进Strongs... 多目标小鼠跟踪是小鼠行为分析的基本任务,是研究社交行为的重要方法。针对传统小鼠跟踪方法存在只能跟踪单只小鼠以及对多目标小鼠跟踪需要对小鼠进行标记从而影响小鼠行为等问题,提出了一种基于实例分割网络YOLO v8n-seg和改进Strongsort相结合的多目标小鼠无标记跟踪方法。使用RGB摄像头采集多目标小鼠的日常行为视频,标注小鼠身体部位分割数据集,对数据集进行增强后训练YOLO v8n-seg实例分割网络,经过测试,模型精确率为97.7%,召回率为98.2%,mAP50为99.2%,单幅图像检测时间为3.5 ms,实现了对小鼠身体部位准确且快速地分割,可以满足Strongsort多目标跟踪算法的检测要求。针对Strongsort算法在多目标小鼠跟踪中存在的跟踪错误问题,对Strongsort做了两点改进:对匹配流程进行改进,将未匹配上目标的轨迹和未匹配上轨迹的目标按欧氏距离进行再次匹配;对卡尔曼滤波进行改进,将卡尔曼滤波中表示小鼠位置和运动状态的小鼠身体轮廓外接矩形框替换为以小鼠身体轮廓质心为中心、对角线为小鼠体宽的正方形框。经测试,改进后Strongsort算法的ID跳变数为14,MOTA为97.698%,IDF1为85.435%,MOTP为75.858%,与原Strongsort相比,ID跳变数减少88%,MOTA提升3.266个百分点,IDF1提升27.778个百分点,与Deepsort、ByteTrack和Ocsort相比,在MOTA和IDF1上均有显著提升,且ID跳变数大幅降低,结果表明改进Strongsort算法可以提高多目标无标记小鼠跟踪的稳定性和准确性,为小鼠社交行为分析提供了一种新的技术途径。 展开更多
关键词 小鼠行为 多目标跟踪 YOLO v8n-seg Strongsort
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层级引导的增强型多目标萤火虫算法 被引量:1
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作者 赵嘉 赖智臻 +2 位作者 吴润秀 崔志华 王晖 《系统仿真学报》 CAS CSCD 北大核心 2024年第5期1152-1164,共13页
针对多目标萤火虫算法在求解过程中易产生振荡和聚集现象,导致开发能力较弱、求解精度不佳的问题,提出一种层级引导的增强型多目标萤火虫算法(hierarchical guided enhanced multi-objective firefly algorithm,HGEMOFA)。构建层级引导... 针对多目标萤火虫算法在求解过程中易产生振荡和聚集现象,导致开发能力较弱、求解精度不佳的问题,提出一种层级引导的增强型多目标萤火虫算法(hierarchical guided enhanced multi-objective firefly algorithm,HGEMOFA)。构建层级引导模型,利用非支配排序获得不同层级个体,用优势层个体引导劣势层个体进化,明确引导方向,解决了进化过程中出现的振荡,减少了聚集现象的出现,增强了算法收敛性;引入莱维飞行扰动最优层个体,增强算法的全局搜索能力;每代进化完成后,对当前种群采用变异机制,增强算法的局部开发能力;把变异后的种群和前一代种群合并进行环境选择,筛选出和前一代种群规模相同的子代,避免优势解丢失。实验结果表明:HGEMOFA能有效增强解的收敛性和多样性。 展开更多
关键词 多目标优化 萤火虫算法 层级引导 莱维飞行 变异
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