检索结果-南通市图书馆

Effects of heat treatment on microstructures and properties of a heterostructured alloy with dissimilar components fabricated by WAAM

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第9期43卷 4441-4461页

作者： Ming-Cai Pan Jun-Qiang Xu Yong Peng ning-ning Liang Si Lan Qi Zhou Ke-Hong Wang School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Key Laboratory of Controlled Arc Intelligent Additive Manufacturing Technology Nanjing 210094China

Heat treatment significantly influences homogeneous material microstructures and mechanical properties,which can be improved by an optimal heat treatment ***,heat treatment application to heterogeneous materials presents significant challenges due to compositional and microstructural ***,a laminated heterostructured alloy comprising alternating316L stainless steel(SS)and 18Ni300 maraging steel(MS)layers fabricated using wire and arc additive manufacturing was investigated.A solution treatment was applied at900℃for 0.5 ***,the solution-treated and asfabricated(AF)samples were aged at 500℃for 4 h;these samples were denoted SA and AT,*** AT phase compositions and orientations were similar to those of *** SA 316L SS layer resembled that of AF,but the SA 18Ni300 MS layers exhibited a reduced austenite phase fraction and refined grain size,attributable to solid-state *** the AT sample,aging induced the formation of nanoscale acicularωphase and ellipsoidal Ni_(3)Ti,Fe_(2)Mo,and X precipitates in the 18Ni300 MS ***,the SA precipitates contained acicular Fe Ni_(2)and ellipsoidalω,Ni_(3)Ti,and X precipitates,and their fractions were lower than those in AT ***18Ni300 MS layer microhardness in the heat-treated samples increased due to nanoprecipitation,but the 316L SS layer microhardness resembled that of *** AT and SA ultimate tensile strengths increased to(1360±50)and(1473±41)MPa,respectively,attributable to precipitation *** SA 316L SS layer exhibited a high stress-induced martensite fraction,enhancing the ductility of heated samples.

关键词： Laminated heterostructured alloy Heat treatment Wire and arc additive manufacturing Microstructure Mechanical property

Near-infrared Emissive 1,2-Dioxetane-based Chemiluminescent Probes

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2024年第5期40卷 806-823页

作者： CHEN Yingqi BUDIANTA Richard ning Yingying Spin-X Institute School of Chemistry and Chemical EngineeringSchool of Biomedical Sciences and EngineeringState Key Laboratory of Luminescent Materials and DevicesGuangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional MaterialsSouth China University of TechnologyGuangzhou510641P.R.China

Chemiluminescence,a phenomenon emitting light from chemical reactions rather than photon absorption,has gained significant interest for applications in bioimaging and biosensing due to its high sensitivity and low background *** there is a growing interest in near-infrared(NIR)chemiluminescent probes for improved tissue penetration and reduced *** review summarizes NIR emissive chemiluminescent probes based on 1,2-dioxetane and discusses their chemical structures and *** modification strategies for red-shifting wavelength and enhancing brightness include incorporating electron-withdrawing groups,designing chemiluminophore-fluorophore cassettes,and exploring alternative chemiluminescent *** review aims to inspire the exploration of NIR chemiluminescent probes in disease detection and treatment.

关键词： Chemiluminescence Near-infrared Dioxetane Bioimaging Biosensing

Spatiotemporal Prediction of Urban Traffics Based on Deep GNN

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第1期78卷 265-282页

作者： Ming Luo Huili Dou ning Zheng School of Computer Science Hangzhou Dianzi UniversityHangzhou310018China Zhejiang Institute of Communications Hangzhou310012China School of Cyberspace Security Hangzhou Dianzi UniversityHangzhou310018China

Traffic prediction already plays a significant role in applications like traffic planning and urban management,but it is still difficult to capture the highly non-linear and complicated spatiotemporal correlations of traffic *** well as to fulfil both long-termand short-termprediction objectives,a better representation of the temporal dependency and global spatial correlation of traffic data is *** order to do this,the Spatiotemporal Graph Neural Network(S-GNN)is proposed in this research as amethod for traffic *** S-GNN simultaneously accepts various traffic data as inputs and investigates the non-linear correlations between the *** terms of modelling,the road network is initially represented as a spatiotemporal directed graph,with the features of the samples at the time step being captured by a convolution *** order to assign varying attention weights to various adjacent area nodes of the target node,the adjacent areas information of nodes in the road network is then aggregated using a graph *** data is output using a fully connected layer at the *** findings show that S-GNN can improve short-and long-term traffic prediction accuracy to a greater extent;in comparison to the control model,the RMSE of S-GNN is reduced by about 0.571 to 9.288 and the MAE(Mean Absolute Error)by about 0.314 to *** experimental results on two real datasets,Pe MSD7(M)and PEMS-BAY,also support this claim.

关键词： Urban traffic traffic temporal correlation GNN prediction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

人性被扭曲了的母亲

韶关学院学报 2006年第1期27卷 1-4页

作者：惠转宁韶关学院中文系广东韶关512005

中国现代文学作品中出现了汪母、七巧、繁漪三位性格被扭曲的母亲形象。性格扭曲变态主要是长期以来伦理道德观念对人性的压抑而导致的后果。中国传统文化对人性尤其是性欲一直是极端的排斥。但性欲是人的天性,是任何力量也无法抑制的。

关键词：中国现代文学人物分析弗洛伊德

A Reliable Iteration Algorithm for One-Bit Compressive Sensing on the Unit Sphere

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年第3期40卷 801-822页

作者： Yan-cheng LU ning BI An-hua WAN School of Mathematics Sun Yat-sen UniversityGuangzhou 510275China

The one-bit compressed sensing problem is of fundamental importance in many areas,such as wireless communication,statistics,and so ***,the optimization of one-bit problem coustrained on the unit sphere lacks an algorithm with rigorous mathematical proof of convergence and *** this paper,an iteration algorithm is established based on difference-of-convex algorithm for the one-bit compressed sensing problem constrained on the unit sphere,with iterating formula■,where C is the convex cone generated by the one-bit measurements andη_(1)>η_(2)>1/*** new algorithm is proved to converge as long as the initial point is on the unit sphere and accords with the measurements,and the convergence to the global minimum point of the l_(1)norm is discussed.

关键词： one-bit compressed sensing difference of convex algorithm iteration algorithm ■1-minimization

Empirical model of concrete block fragment behavior under explosion loads

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第8期67卷 2515-2529页

作者： YANG Shuai ning JianGuo REN HuiLan XU XiangZhao State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of TechnologyBeijing 100081China

Concrete structures undergo integral fragmentation under explosion loads. The fragmentation degree and particle-size distribution of concrete blocks under explosion loads must be considered during mining to ensure safety. In this study, the impulse is calculated based on the relationship between overpressure and time, and the impact energy of the explosion wave is obtained based on blast theory. Subsequently, the Mohr-Coulomb shear strength fracture criterion is introduced to determine the ultimate shear stress of the concrete materials, and an empirical model that can effectively calculate the energy consumption of concrete blocks under explosion loads is established. Furthermore, concrete fragments with different particle sizes under explosion scenarios are quantitatively predicted with the principle of energy conservation. Finally, explosion tests with different top standoff distances are conducted, and the concrete fragments after the explosion tests are recovered, sieved, weighed, and counted to obtain experimental data. The effectiveness of the fragment empirical model is verified by comparing the model calculation results with the experimental data. The proposed model can be used as a reference for civil blasting, protective engineering design, and explosion-damage assessment.

关键词： concrete structures explosion loads fragment behavior empirical model

A novel cylindrical sandwich plate inspired by beetle elytra and its compressive properties

在线全文

学校读者我要写书评

暂无评论

Science China Technological Sciences 2024年第11期67卷 3465-3476页

作者： SONG YiHeng RUAN SiHan HAO ning OKABE YoJi School of Engineering The University of Tokyo School of Civil Engineering Southeast University School of Engineering RMIT University Institute of Industrial Science The University of Tokyo

The design and experimental analysis of a semi-cylindrical structure known as the cylindrical beetle elytron plate(CBEP) were presented. Radial compression tests and finite element simulation were performed on CBEPs under 30° and 45° inclined sliding support constraints, with a comparison made to cylindrical honeycomb plate(CHP). The study aims to investigate the superior compression performance and enhancement mechanisms of CBEPs. The results demonstrate that CBEPs exhibit a 14%–26% increase in specific load-bearing capacity and a 20% increase in specific energy absorption compared with CHPs with equal core wall thickness. Distinct “Z-shaped” tearing failures were observed, with honeycomb plates showing tearing at the center of the honeycomb walls, while beetle elytron plates exhibited tearing along the midline of the trabeculae. Three different stress patterns,including elastic-plastic development stage of arch, plastic hinge node stage, and rigid node stage, were identified and analyzed to explain the mechanical performance improvements and failure characteristics. Considering that structural damage to trabeculae mostly occurs at its junction with the skin, it is recommended to add chamfers to the junctions of CBEP. Therefore, this paper lays the groundwork for the engineering application of CBEP.

关键词： beetle elytron cylindrical beetle elytron plate compression performance failure characteristics enhancement mechanism

STDNet: A Spatio-Temporal Decomposition Neural Network for Multivariate Time Series Forecasting

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2024年第4期29卷 1232-1247页

作者： Zhuolun Jiang Zefei ning Hao Miao Li Wang College of Computer Science and Technology(College of Data Science) Taiyuan University of TechnologyJinzhong 030600China

Long-term multivariate time series forecasting is an important task in engineering applications. It helps grasp the future development trend of data in real-time, which is of great significance for a wide variety of fields. Due to the non-linear and unstable characteristics of multivariate time series, the existing methods encounter difficulties in analyzing complex high-dimensional data and capturing latent relationships between multivariates in time series, thus affecting the performance of long-term prediction. In this paper, we propose a novel time series forecasting model based on multilayer perceptron that combines spatio-temporal decomposition and doubly residual stacking, namely Spatio-Temporal Decomposition Neural Network (STDNet). We decompose the originally complex and unstable time series into two parts, temporal term and spatial term. We design temporal module based on auto-correlation mechanism to discover temporal dependencies at the sub-series level, and spatial module based on convolutional neural network and self-attention mechanism to integrate multivariate information from two dimensions, global and local, respectively. Then we integrate the results obtained from the different modules to get the final forecast. Extensive experiments on four real-world datasets show that STDNet significantly outperforms other state-of-the-art methods, which provides an effective solution for long-term time series forecasting.

关键词： time series forecasting multivariate time series spatio-temporal decomposition

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

张爱玲与传统文学中的“意象”

沈阳师范大学学报（社会科学版） 2005年第3期29卷 87-90页

作者：惠转宁韶关学院中文系广东韶关512005

张爱玲不幸的家庭生活及乱世战争的人生体验,使她笔下的人物皆处于孤独、隔膜的状态中。作品中镜子、月亮等传统意象的运用,更细微逼真地传达出人物虚无与绝望的生存困境及特定的心理状态,以此建构出她笔下的“苍凉”世界。

关键词：传统文学意象镜子月亮