检索结果-南通市图书馆

Journal of Thermal Science 2024年第5期33卷 1946-1960页

作者： yu Chunkan YANG Bin Institute of Technical Thermodynamics Karlsruhe Institute of TechnologyKarlsruhe 76131Germany Center for Combustion Energy Tsinghua UniversityBeijing 100084China

In this study,we conduct a thorough evaluation of the STGSA-generated skeletal mechanism for C_(2)H_4/*** STGSA-reduced mechanisms are taken into account,incorporating basic combustion models such as the homogeneous reactor model,one-dimensional flat premixed flame,and non-premixed counterflow ***,these models are applied to more complex combustion systems,considering factors like flame-flow interaction and flame-wall *** considerations take into account additional physical parameters and processes such as mixing frequency and *** results indicate that the skeletal mechanism adeptly captures the behavior of these complex combustion ***,it is suggested to incorporate strain rate considerations in generating the skeletal mechanism,especially when the combustion system operates under high turbulent intensity.

关键词： Species-Targeted Global Sensitivity Analysis(STGSA) mechanism reduction Partially Stirred Reactor(PaSR) spark ignition Head-on Quenching(HoQ)

Dynamic Setting Method of Assessment Indicators for Power Curves of Renewable Energy Sources Considering Scarcity of Reserve Resources

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 101-114页

作者： Minghao Cao Jilai yu the Department of Electrical Engineering Harbin Institute of TechnologyHarbinChina

With the increasing proportion of renewable energy sources(RESs)in power grid,the reserve resource(RR)scarcity for correcting power deviation of RESs has become a potential ***,the power curve of RES needs to be more rigorously *** RR scarcity varies during different time periods,so the values of assessment indicators should be dynamically *** assessment indicators in this paper include two aspects,i.e.,deviation exemption ratio and penalty ***,this paper proposes a method for dynamically calculating the supply capacity and RR cost,primarily taking into account the operating status of thermal units,forecast information of RES,and load ***,after clarifying the logical relationship between the degree of RR scarcity and the values of assessment indicators,this paper establishes a mapping function between *** on this mapping function,a dynamic setting method for assessment indicators is *** the future,RES will generally be equipped with battery energy storage systems(BESSs).Reasonably utilizing BESSs to reduce the power deviation of RESs can increase the expected income of ***,this paper proposes a power curve optimization strategy for RESs considering self-owned *** case study demonstrates that the dynamic setting method of assessment indicators can increase the revenue of RESs while ensuring that the penalty fees paid by RESs to the grid are sufficient to cover the RR ***,the power curve optimization strategy can help RESs further increase income and fully utilize BESSs to reduce power deviation.

关键词： Renewable energy battery energy storage system(BESS) power curve assessment reserve service parameter setting

Biotreatment of incinerated bottom ash and biocementation of sand blocks using soybean urease

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第1期25卷 36-46页

作者： Xiaoniu yu Yidong XU Jiangsu Key Laboratory of Construction Materials Southeast UniversityNanjing211189China School of Civil Engineering and Architecture NingboTech UniversityNingbo315100China

Because of the high cost of cultivating urease-producing bacteria(UPB),this paper proposes soybean-urease-induced carbonate precipitation(SUICP)as a novel biocement for treatment of nickel contaminants and cementation of sandy *** found the optimal soaking time and soybean-powder content to be 30 min and 130 g/L,respectively,based on a standard of 5 U of urease *** most efficient removal of nickel ions is obtained with an ideal mass ratio of urea to nickel ions to soybean-powder filtrate(SPF)of 1:2.4:*** removal efficiency of nickel ions can reach 89.42%when treating 1 L of nickel-ion solution(1200 mg/L with the optimal mass ratio).In incinerated bottom ash(IBA),the removal efficiency of nickel ions is 99.33%with the optimal mass *** biocemented sandy soil,the average unconfined compressive strength(UCS)of sand blocks cemented with soybean urease-based biocement can reach 118.89 kPa when the cementation level is ***,the average content of CaCO_(3)in sand blocks is 2.52%.As a result,the SUICP process can be applied to remove heavy metal ions in wastewater or solid waste and improve the mechanical properties of soft soil foundations.

关键词： Biocement Soybean-powder filtrate(SPF) Removal efficiency Sandy soil Unconfined compressive strength(UCS)

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

中国区域平流层气温垂直变化统计特征

中国科技论文 2018年第3期13卷 279-285页

作者：于雪涛芮小平张栋赵苗琦石家庄铁道大学交通运输学院石家庄050043 中国科学院大学资源与环境学院北京100049 包头市气象局内蒙古包头014030 河北省第三测绘院石家庄050031

为了准确获取气温的垂直变化特征,选用2008—2012年的TLogP探空数据,采用回归分析等方法,研究了中国地理区域内气温直减率和逆温层的时空分布特征。结果表明:华中、华南和华东区域的气温直减率年均值较高,其他区域较低;西南、西北、东... 详细信息

为了准确获取气温的垂直变化特征,选用2008—2012年的TLogP探空数据,采用回归分析等方法,研究了中国地理区域内气温直减率和逆温层的时空分布特征。结果表明:华中、华南和华东区域的气温直减率年均值较高,其他区域较低;西南、西北、东北和华北区域的气温直减率在夏季和冬季较高,而华中、华南和华东区域只在冬季较高;中国境内的逆温层一般出现在春季和冬季,且早上比晚上多;逆温层在华南和华东区域出现次数较多,而在西南区域较少;在西南和西北区域,近地表2km以下大气中一般具有2个逆温层,而其他区域一般具有3层。

关键词：气温直减率逆温层时空分布中国地理区域

Annihilator Ideals of Indecomposable Modules of Finite-Dimensional Pointed Hopf Algebras of Rank One

在线全文

学校读者我要写书评

暂无评论

Algebra Colloquium 2024年第1期31卷 149-164页

作者： yu Wang School of Mathematics and Physics Jiangsu University of Technology ChangzhouJiangsu 213001China

Let H be a finite-dimensional pointed Hopf algebra of rank one over an algebraically closed feld of characteristic *** describe all annihilator ideals of indecomposable H-modules by *** particular,we give the classification of all ideals of the finite-dimensional pointed rank one Hopf algebra of nilpotent type over the Klein 4-group.

关键词： indecomposable module annihilator ideal primitive central orthogonal idem-potent element

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MapGIS的地质图制作方法探究

金属矿山 2010年第9期39卷 87-90页

作者：牛坤徐雷奚砚涛于雪涛于书媛中国矿业大学江苏省有色金属华东地质勘查局

MapGIS是集图形、图像、地质、地理、遥感、人工智能、计算机科学为一体的智能软件系统。运用MapGIS软件,能够方便地绘制各种地质图、地形图,提高制图效率,缩短制图时间。以徐州市基岩地质图为例,对在MapGIS中制作地质图的过程和方法进... 详细信息

MapGIS是集图形、图像、地质、地理、遥感、人工智能、计算机科学为一体的智能软件系统。运用MapGIS软件,能够方便地绘制各种地质图、地形图,提高制图效率,缩短制图时间。以徐州市基岩地质图为例,对在MapGIS中制作地质图的过程和方法进行了探讨和分析,提出了一些方法及原则。

关键词： MapGIS 矢量化地质图

Characteristics of a pre-combustion plasma jet igniter

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第7期37卷 178-189页

作者： Jinlu yu Baowen ZHANG Yang yu Bingbing ZHAO Lei ZHANG Aviation Engineering School Air Force Engineering UniversityXi’an 710038China Equipment Management and Unmanned Aerial Vehicle Engineering School Air Force Engineering UniversityXi’an 710038China

Plasma ignition technology has delivered good performance in the aerospace industry. In this study, a pre-combustion plasma jet igniter was designed, and its characteristics were examined from three aspects: the morphology, temperature, and discharge characteristics and process of ignition. Images of the OH distribution were obtained by using an OH Planar Laser-Induced Fluorescence(OH-PLIF) experimental system. Results have shown that the proposed plasma jet had a higher OH concentration, longer length, and larger area than those of a traditional igniter. The stability of discharge of the igniter was improved as the equivalence ratio φ was increased, and reducing gas flow reduced the pulsation of the plasma jet. When the input current was increased from 15A to 35 A, the highest average temperature increased from 5127 K to 7987 K. An increase in the equivalence ratio reduced the region of arc ionization, but expanded the regions of the core combustion reaction and the outer flame. Herein, this study has obtained a deep understanding of the jet and ignition law and developed a new idea for the application of plasma in the ignition field.A pre-combustion plasma jet igniter can significantly improve the efficiency of ignition and shorten the ignition process compared with a traditional igniter.

关键词： Pre-combustion plasma igniter Plasma Jet temperature field Ignition process Arc Flame

A probabilistic generative model for tracking multi-knowledge concept mastery probability

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2024年第3期18卷 155-170页

作者： Hengyu LIU Tiancheng ZHANG Fan LI Minghe yu Ge yu School of Computer Science and Engineering Northeastern UniversityShenyang 110169China Software College Northeastern UniversityShenyang 110169China

Knowledge tracing aims to track students’knowledge status over time to predict students’future performance *** a real environment,teachers expect knowledge tracing models to provide the interpretable result of knowledge *** chain-based knowledge tracing(MCKT)models,such as Bayesian Knowledge Tracing,can track knowledge concept mastery probability over ***,as the number of tracked knowledge concepts increases,the time complexity of MCKT predicting student performance increases exponentially(also called explaining away problem).When the number of tracked knowledge concepts is large,we cannot utilize MCKT to track knowledge concept mastery probability over *** addition,the existing MCKT models only consider the relationship between students’knowledge status and problems when modeling students’responses but ignore the relationship between knowledge concepts in the same *** address these challenges,we propose an inTerpretable pRobAbilistiC gEnerative moDel(TRACED),which can track students’numerous knowledge concepts mastery probabilities over *** solve explain away problem,we design long and short-term memory(LSTM)-based networks to approximate the posterior distribution,predict students’future performance,and propose a heuristic algorithm to train LSTMs and probabilistic graphical model *** better model students’exercise responses,we proposed a logarithmic linear model with three interactive strategies,which models students’exercise responses by considering the relationship among students’knowledge status,knowledge concept,and *** conduct experiments with four real-world datasets in three knowledge-driven *** experimental results show that TRACED outperforms existing knowledge tracing methods in predicting students’future performance and can learn the relationship among students,knowledge concepts,and problems from students’exercise *** also conduct several case *** case studies show that

关键词： probabilistic graphical model deep learning knowledge tracing learner modeling

Macroporous Directed and Interconnected Carbon Architectures Endow Amorphous Silicon Nanodots as Low‑Strain and Fast‑Charging Anode for Lithium‑Ion Batteries

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

Nano-Micro Letters 2024年第5期16卷 333-351页

作者： Zhenwei Li Meisheng Han Peilun yu Junsheng Lin Jie yu Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems Shenzhen Engineering Lab for Supercapacitor MaterialsSchool of Material Science and EngineeringHarbin Institute of TechnologyShenzhenUniversity TownShenzhen 518055People’s Republic of China Songshan Lake Materials Laboratory Dongguan Dongguan 523808GuangdongPeople’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

Fabricating low-strain and fast-charging silicon-carbon composite anodes is highly desired but remains a huge challenge for lithium-ion ***,we report a unique silicon-carbon composite fabricated by uniformly dis-persing amorphous Si nanodots(SiNDs)in carbon nanospheres(SiNDs/C)that are welded on the wall of the macroporous carbon framework(MPCF)by vertical graphene(VG),labeled as MPCF@VG@SiNDs/*** high dispersity and amor-phous features of ultrasmall SiNDs(~0.7 nm),the flexible and directed electron/Li+transport channels of VG,and the MPCF impart the MPCF@VG@SiNDs/C more lithium storage sites,rapid Li+transport path,and unique low-strain property during Li+***,the MPCF@VG@SiNDs/C exhibits high cycle stability(1301.4 mAh g^(-1) at 1 A g^(-1) after 1000 cycles without apparent decay)and high rate capacity(910.3 mAh g^(-1),20 A g^(-1))in half cells based on industrial electrode *** assembled pouch full cell delivers a high energy density(1694.0 Wh L^(-1);602.8 Wh kg^(-1))and an excellent fast-charging capability(498.5 Wh kg^(-1),charging for 16.8 min at 3 C).This study opens new possibilities for preparing advanced silicon-carbon com-posite anodes for practical applications.

关键词： Amorphous Si nanodots Low-strain Fast-charging Lithium-ion batteries

Hybrid pedestrian positioning system using wearable inertial sensors and ultrasonic ranging

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 327-338页

作者： Lin Qi yu Liu Chuanshun Gao Tao Feng yue yu School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong Kong 999077China

Pedestrian positioning system(PPS)using wearable inertial sensors has wide applications towards various emerging fields such as smart healthcare,emergency rescue,soldier positioning,*** performance of traditional PPS is limited by the cumulative error of inertial sensors,complex motion modes of pedestrians,and the low robustness of the multi-sensor collaboration *** paper presents a hybrid pedestrian positioning system using the combination of wearable inertial sensors and ultrasonic ranging(H-PPS).A robust two nodes integration structure is developed to adaptively combine the motion data acquired from the single waist-mounted and foot-mounted node,and enhanced by a novel ellipsoid constraint *** addition,a deep-learning-based walking speed estimator is proposed by considering all the motion features provided by different nodes,which effectively reduces the cumulative error originating from inertial ***,a comprehensive data and model dual-driven model is presented to effectively combine the motion data provided by different sensor nodes and walking speed estimator,and multi-level constraints are extracted to further improve the performance of the overall *** results indicate that the proposed H-PPS significantly improves the performance of the single PPS and outperforms existing algorithms in accuracy index under complex indoor scenarios.

关键词： Pedestrian positioning system Wearable inertial sensors Ultrasonic ranging Deep-learning Data and model dual-driven