检索结果-南通市图书馆

Particle Distribution Informed by Chain Rigidity in Diblock Copolymer Melts: The Effect of Entropy

Chinese Journal of Polymer Science 2024年第3期42卷 388-399,I0009页

作者： Yuguo Chen Shuanhu Qi Ying jiang School of Chemistry Beihang UniversityBeijing 100191China

We study the effect of chain rigidity on tailoring the nanoparticle locations for neutral and selective particles embedded in the lamellar morphology formed by semiflexible diblock copolymer chains using self-consistent field calculations. The nanoparticles are modeled through a cavity function, and the semiflexible chains are represented by the continuous Kratsky-Porod chain model. In general situation, the nanoparticles prefer to stay at the interface in order to reduce the interface areas and thus the system free energy. However, the particle distribution at the domain center is subtle, and the underlying physics is intrinsically different depending on the polymer flexibility. In the case of flexible chains, the entropy just contributes a constant shift to the free energy when the nanoparticles move around the domain center indicating that the local metastable state if appears at the domain center is wholly attributed to the local minimum in the enthalpy. If the polymers are rigid, the variation of the particle distribution at the domain center has a close relation with the polymer rigidity and nanoparticle size. In the case of strongly rigid polymers with small nanoparticles, a nearly uniform particle distribution at the domain center is observed, while in other cases, a local enhancement of particle distribution there is found. In contrast to the case of flexible chains, further analysis reveals the crucial role of entropy in controlling the shape of particle distributions at the phase domain. Specifically, the local metastable state appears in the domain center is determined by the large entropy there which arises from the weak coupling of bond orientations that allows the polymer chains to be relatively relaxed. When the particle becomes selective, its distribution in the phase domain exhibits a shift almost uniformly rather than changes its profile, and the underlying physics still holds. In all, our study establishes a strong coupling between the chain rigi

关键词： Semiflexible diblock copolymer Nanoparticle distribution Self-consistent field theory Entropic effect

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

残余应力对W-Cu复合材料导热性能的影响

引用

稀有金属材料与工程 2005年第12期34卷 1982-1984页

作者：陈德欣王志法姜国圣张瑾瑾唐仁正中南大学湖南长沙410083

用熔渗法制备的W-cu复合材料在小批量生产时,发现熔渗结束后样品的热导率数据分散不稳定,受熔渗时摆放位置的影响很大。将熔渗结束后的样品退火,采取不同的方式冷却。用X射线衍射法测量其残余应力,用热脉冲法测量其热导率,研究了残余应... 详细信息

用熔渗法制备的W-cu复合材料在小批量生产时,发现熔渗结束后样品的热导率数据分散不稳定,受熔渗时摆放位置的影响很大。将熔渗结束后的样品退火,采取不同的方式冷却。用X射线衍射法测量其残余应力,用热脉冲法测量其热导率,研究了残余应力对材料导热性能的影响。结果表明：随冷却速度的加快,残余应力值增大,热导率降低。钨和铜的热膨胀系数相差较大,从高温冷到室温时两相收缩程度不一样,冷却速度过快时,在界面处产生残余应力,使材料的热导率降低。分析了残余应力对材料导热性能的影响及机制。

关键词： W-Cu复合材料残余应力热导率

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Response of ocean acidification to atmospheric carbon dioxide removal

引用

Journal of Environmental Sciences 2024年第6期140卷 79-90页

作者： Jiu jiang Long Cao Xiaoyu Jin Zechen Yu Han Zhang Jianjie Fu Guibin jiang School of Environment Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Key Laboratory of Geoscience Big Data and Deep Resources of Zhejiang Province School of Earth SciencesZhejiang UniversityHangzhou 310058China Zhejiang Climate Center Hangzhou 310052China

Artificial CO_(2)removal from the atmosphere(also referred to as negative CO_(2)emissions)has been proposed as a potential means to counteract anthropogenic climate *** we use an Earth system model to examine the response of ocean acidification to idealized atmospheric CO_(2)removal *** our simulations,atmospheric CO_(2)is assumed to increase at a rate of 1%per year to four times its pre-industrial value and then decreases to the pre-industrial level at a rate of 0.5%,1%,2%per year,*** results show that the annual mean state of surface ocean carbonate chemistry fields including hydrogen ion concentration([H^(+)]),pH and aragonite saturation state respond quickly to removal of atmospheric CO_(2).However,the change of seasonal cycle in carbonate chemistry lags behind the decline in atmospheric CO_(2).When CO_(2)returns to the pre-industrial level,over some parts of the ocean,relative to the pre-industrial state,the seasonal amplitude of carbonate chemistry fields is substantially *** results also show that changes in deep ocean carbonate chemistry substantially lag behind atmospheric CO_(2)*** CO_(2)returns to its pre-industrial value,the whole-ocean acidity measured by[H^(+)]is 15%-18%larger than the pre-industrial level,depending on the rate of CO_(2)*** study demonstrates that even if atmospheric CO_(2)can be lowered in the future as a result of net negative CO_(2)emissions,the recovery of some aspects of ocean acidification would take decades to centuries,which would have important implications for the resilience of marine ecosystems.

关键词： Carbon dioxide removal Net negative CO_(2)emission Ocean acidification Climate change Earth system modeling

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Rhyscotus subrisus Li&jiang,***.,representing a new record family Rhyscotidae from China(Isopoda:Oniscidea)

引用

Zoological Systematics 2024年第2期49卷 181-183页

作者： Chonghui Yao Chao jiang Weichun Li College of Agronomy Jiangxi Agricultural UniversityNanchang 330045China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs National Resource Center for Chinese MateriaMedicaChina Academy of Chinese Medical SciencesBeijing 100700China

The family Rhyscotidae Budde-Lund,1904 contains two genera:Rhyscotoides Schmalfuss&Ferrara,1978 and Rhyscotus Budde-Lund,*** date,twenty-one species within the family are known,occurring in the subtropic and tropic regions(Schmalfuss,2003;Schmidt,2003;Boyko et al.,2022).The members of the family can be recognized by the cephalon with a strongly inflated frons,the antennae with two-jointed flagellum,the maxillae are almost semicircular,the maxillipeds have short palpus and endite,and pleopod exopodites without pseudotracheae(Schmalfuss&Ferrara,1978).Before this study,the members of Rhyscotidae were unknown in *** present research describes a new species of the genus Rhyscotus from Hainan Island,representing a new record of the family Rhyscotidae from China.

关键词： record family

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Recent Advances on Deep Learning for Sign Language Recognition

引用

Computer Modeling in Engineering & Sciences 2024年第6期139卷 2399-2450页

作者： Yanqiong Zhang Xianwei jiang School of Mathematics and Information Science Nanjing Normal University of Special EducationNanjing210038China

Sign language,a visual-gestural language used by the deaf and hard-of-hearing community,plays a crucial role in facilitating communication and promoting *** language recognition(SLR),the process of automatically recognizing and interpreting sign language gestures,has gained significant attention in recent years due to its potential to bridge the communication gap between the hearing impaired and the hearing *** emergence and continuous development of deep learning techniques have provided inspiration and momentum for advancing *** paper presents a comprehensive and up-to-date analysis of the advancements,challenges,and opportunities in deep learning-based sign language recognition,focusing on the past five years of *** explore various aspects of SLR,including sign data acquisition technologies,sign language datasets,evaluation methods,and different types of neural *** Neural Networks(CNN)and Recurrent Neural Networks(RNN)have shown promising results in fingerspelling and isolated sign ***,the continuous nature of sign language poses challenges,leading to the exploration of advanced neural network models such as the Transformer model for continuous sign language recognition(CSLR).Despite significant advancements,several challenges remain in the field of *** challenges include expanding sign language datasets,achieving user independence in recognition systems,exploring different input modalities,effectively fusing features,modeling co-articulation,and improving semantic and syntactic ***,developing lightweight network architectures for mobile applications is crucial for practical *** addressing these challenges,we can further advance the field of deep learning for sign language recognition and improve communication for the hearing-impaired community.

关键词： Sign language recognition deep learning artificial intelligence computer vision gesture recognition

来源：

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

Growth of Ag/g-C_(3)N_(4) nanocomposites on nickel foam to enhance photocatalytic degradation of formaldehyde under visible light

引用

Journal of Environmental Sciences 2024年第3期137卷 432-442页

作者： Ze Wang Zhi Huang jiang Yu Xiao Shao Weidong Peng Jie Yu Yinying jiang Department of Environmental Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Institute of New Energy and Low Carbon Technology Sichuan UniversityChengdu 610065China School of Agriculture and Environment University of Western AustraliaPerth 6907Western AustraliaAustralia Yibin Institute of Industrial Technology Sichuan UniversityYibin 644000China

Formaldehyde is a pollutant that significantly affects the indoor air ***,conventional remediation approaches can be challenging to deal with low-concentration formaldehyde in an indoor *** this study,Photocatalysts of Ag/graphitic carbon nitride(g-C_(3)N_(4))/Ni with 3D reticulated coral structure were prepared by thermal polymerization and liquid phase photo-deposition,using nickel foam(NF)as the *** demonstrated that when the Ag concentration was 3%,and the relative humidity was 60%,the Ni/Ag/g-C_(3)N_(4)showed the maximum degradation rate of formaldehyde at 90.19%under visible light irradiation,and the formaldehyde concentration after degradation was lower than the Hygienic standard stated by the Chinese *** porous structure of Ni/Ag/g-C_(3)N_(4)and the formation of Schottky junctions promoted the Adsorption efficiency and degradation of formaldehyde,while the nickel foam carrier effectively promoted the desorption of degradation ***,the degradation rate was only reduced by3.4%after 16 recycles,the three-dimensional porous structure extended the lifetime of the *** study provides a new strategy for the degradation of indoor formaldehyde at low concentrations.

关键词： Graphitic carbon nitride(g-C_(3)N_(4)) Nickel foam(NF) Ag Formaldehyde Photocatalysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Review of Collocation Methods and Applications in Solving Science and Engineering Problems

引用

Computer Modeling in Engineering & Sciences 2024年第7期140卷 41-76页

作者： Weiwu jiang Xiaowei Gao School of Aeronautics and Astronautics Dalian University of TechnologyDalian116024China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian116024China

The collocation method is a widely used numerical method for science and engineering problems governed by partial differential *** paper provides a comprehensive review of collocation methods and their applications,focused on elasticity,heat conduction,electromagnetic field analysis,and fluid *** merits of the collocation method can be attributed to the need for element mesh,simple implementation,high computational efficiency,and ease in handling irregular domain problems since the collocation method is a type of node-based numerical *** with the fundamental principles of the collocation method,the discretization process in the continuous domain is elucidated,and how the collocation method approximation solutions for solving differential equations are *** into the historical development of the collocation methods,their earliest applications and key milestones are traced,thereby demonstrating their evolution within the realm of numerical *** mathematical foundations of collocation methods,encompassing the selection of interpolation functions,definition of weighting functions,and derivation of integration rules,are examined in detail,emphasizing their significance in comprehending the method’s effectiveness and *** last,the practical application of the collocation methods in engineering contexts is emphasized,including heat conduction simulations,electromagnetic coupled field analysis,and fluid dynamics *** specific case studies can underscore collocation method’s broad applicability and effectiveness in addressing complex engineering *** conclusion,this paper puts forward the future development trend of the collocation method through rigorous analysis and discussion,thereby facilitating further advancements in research and practical applications within these fields.

关键词： Collocation method meshless method discrete schemes for functions numerical calculation

来源：

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

A Real-Time Small Target Vehicle Detection Algorithm with an Improved YOLOv5m Network Model

引用

Computers, Materials & Continua 2024年第1期78卷 303-327页

作者： Yaoyao Du Xiangkui jiang School of Automation Xi’an University of Posts and TelecommunicationsXi’an710121China

To address the challenges of high complexity,poor real-time performance,and low detection rates for small target vehicles in existing vehicle object detection algorithms,this paper proposes a real-time lightweight architecture based on You Only Look Once(YOLO)***,a lightweight upsampling operator called Content-Aware Reassembly of Features(CARAFE)is introduced in the feature fusion layer of the network to maximize the extraction of deep-level features for small target vehicles,reducing the missed detection rate and false detection ***,a new prediction layer for tiny targets is added,and the feature fusion network is redesigned to enhance the detection capability for small ***,this paper applies L1 regularization to train the improved network,followed by pruning and fine-tuning operations to remove redundant channels,reducing computational and parameter complexity and enhancing the detection efficiency of the *** is conducted on the VisDrone2019-DET *** experimental results show that the proposed algorithmreduces parameters and computation by 63.8% and 65.8%,*** average detection accuracy improves by 5.15%,and the detection speed reaches 47 images per second,satisfying real-time *** with existing approaches,including YOLOv5m and classical vehicle detection algorithms,our method achieves higher accuracy and faster speed for real-time detection of small target vehicles in edge computing.

关键词： Vehicle detection YOLOv5m small target channel pruning CARAFE

来源：

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

Feedback processing in the primate brain and in AI systems

引用

Science China(Technological Sciences) 2024年第8期67卷 2297-2309页

作者： jiang Yong HE Sheng Institute of Biophysics Chinese Academy of SciencesBeijing 100101China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China University of Chinese Academy of Sciences Beijing 100049China

The primate brain and artificial intelligence(AI) can both be conceptualized as information processing systems, each with its own distinct biological and computational architectures. While there are parallels between them, their respective structural and functional connections show significant differences. In this paper, we examine the central role of feedback processing in both the primate brain and AI systems, which has been shown to be crucial in shaping neural processing. By reviewing the key features of feedback processes in the primate brain, which allows the brain to incorporate prior knowledge, contextual information, and taskdemands into early-stage processing, we highlight the divergence in goals and functions between biological and AI *** these differences is crucial for elucidating the cognitive capabilities of the primate brain and for addressing computational challenges in AI. In advocating “Cognition-Inspired-Computation”, we suggest that integrating insights from feedback processing in the primate brain into AI research will offer potentially significant improvements for the advancement of AI systems.

关键词： cognitive neuroscience artificial intelligence feedback processing attention learning

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A New Solution to Intrusion Detection Systems Based on Improved Federated-Learning Chain

引用

Computers, Materials & Continua 2024年第6期79卷 4491-4512页

作者： Chunhui Li Hua jiang School of Computer and Electronic Information Guangxi UniversityNanning530000China Cyber Security and Information Center Guangxi UniversityNanning530000China

In the context of enterprise systems,intrusion detection(ID)emerges as a critical element driving the digital transformation of *** systems spanning various sectors of enterprises geographically dispersed,the necessity for seamless information exchange has surged *** existing cross-domain solutions are challenged by such issues as insufficient security,high communication overhead,and a lack of effective update mechanisms,rendering them less feasible for prolonged application on resource-limited *** study proposes a new cross-domain collaboration scheme based on federated chains to streamline the server-side *** this framework,individual nodes solely engage in training local data and subsequently amalgamate the final model employing a federated learning algorithm to uphold enterprise systems with efficiency and *** curtail the resource utilization of blockchains and deter malicious nodes,a node administration module predicated on the workload paradigm is introduced,enabling the release of surplus resources in response to variations in a node’s contribution *** encountering an intrusion,the system triggers an alert and logs the characteristics of the breach,facilitating a comprehensive global update across all nodes for collective *** results across multiple scenarios have verified the security and effectiveness of the proposed solution,with no loss of its recognition accuracy.

关键词： Cross-domain collaboration blockchain federated learning contribution value node management release slack resources

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：