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Journal of Environmental Sciences 2024年第2期136卷 35-44页

作者： Yunhua zhang diming Lou Piqiang Tan Zhiyuan Hu Liang Fang School of Automotive Studies Tongji UniversityShanghai 201804China

In this study,the effect of new and used catalyzed diesel particulate filter(CDPF)with different catalyst loadings on the particulate emissions including the particle mass(PM),particle number(PN),particle size distribution(PSD)and geometric mean diameter(GMD)from a diesel vehicle were investigated based on a heavy chassis *** showed that more than 97.9%of the PN and 95.4%of the PM were reduced by the CDPF,and the reduction efficiency was enhanced by the catalyst *** using the CDPF,the PSD transformed from bimodal to trimodal with the peak shifting towards smaller particle size,more nucleation mode particles were reduced compared with accumulation mode ones,but the reduction effect on the accumulation mode particles was more significantly influenced by the catalyst ***,the CDPF increased the accumulation mode particles proportion,producing a larger *** the used CDPF,its reduction effect on the particulate emissions enhanced,especially for the PM in accumulation *** PSD returned to bimodal,but the peak at accumulation mode began to be higher than that at nucleation mode,illustrating that more nucleation mode particles was *** aging of the CDPF resulted in greater effect on the PN-based PSD than that of PM-based PSD,but the effect of catalyst loading on the PN and PM emission factors was *** used CDPF further increased the GMD,and the effect of catalyst loading on the GMD was strengthened,a higher catalyst loading led to a reduction in the GMD.

关键词： Catalyzed diesel particulate filter (CDPF) Catalyst loading Aging Particle Particle size distribution Geometric mean diameter

动脉自旋标记联合扩散张量成像对腮腺肿瘤的鉴别诊断价值

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磁共振成像 2024年第3期15卷 50-55页

作者：周金亮崔运福张迪鸣任瑞狄宁宁沈善昌姜兴岳王山山滨州医学院附属医院放射科滨州256600 滨州医学院附属医院门诊部滨州256600

目的探讨应用动脉自旋标记(arterial spin labeling,ASL)和扩散张量成像(diffusion tensor imaging,DTI)评价多参数MRI在鉴别腮腺肿瘤中的临床价值。材料与方法回顾性分析滨州医学院附属医院2019年6月至2023年11月66名经手术病理证实的... 详细信息

目的探讨应用动脉自旋标记(arterial spin labeling,ASL)和扩散张量成像(diffusion tensor imaging,DTI)评价多参数MRI在鉴别腮腺肿瘤中的临床价值。材料与方法回顾性分析滨州医学院附属医院2019年6月至2023年11月66名经手术病理证实的腮腺肿瘤患者,术前均行3D ASL和DTI,并测量肿瘤最大血流量(maximum tumor blood flow,TBFmax)和最小表观扩散系数(minimum apparent diffusion coefficient,ADCmin)、各向异性分数(fraction anisotropy,FA)。使用Mann-Whitney U检验或Kruskal-Wallis检验比较良性肿瘤(benign tumors,BT)和恶性肿瘤(malignant tumors,MT)的各参数值。使用受试者工作特征(receiver operating characteristic,ROC)曲线分析评估各参数和联合有差异的参数对腮腺肿瘤的诊断效能。结果66例腮腺肿瘤患者中,BT 55例[其中Warthin瘤(Warthin tumors,WT)15例,多形性腺瘤(pleomorphic adenomas,PA)23例,其他17例],MT11例。BT的FA值低于MT(0.13±0.06 vs.0.18±0.04,P=0.003)。PA的TBFmax值[(43.72±37.64)mL/(100 g·min^(-1))]低于MT[(92.56±58.26)mL/(100 g·min^(-1))](P<0.001)和WT[(145.26±64.54)mL/(100 g·min^(-1))](P=0.016)。PA的ADCmin值[(1.55±0.51)×10^(-3)mm^(2)/s]高于MT[(1.11±0.28)×10^(-3)mm^(2)/s](P=0.016)和WT[(1.03±0.53)×10^(-3)mm^(2)/s](P<0.001)。MT的FA值(0.18±0.05)高于PA(0.11±0.04)(P<0.001)和WT(0.12±0.02)(P=0.015)。FA鉴别腮腺BT与MT的曲线下面积(area under the curve,AUC)为0.78,敏感度、特异度分别为81.82%、70.18%。FA区分WT、PA与MT的AUC分别为0.85、0.87,敏感度分别为72.73%、100.00%,特异度分别为94.12%、65.22%。TBFmax、ADCmin鉴别WT与PA的AUC分别为0.90、0.85,敏感度分别为94.12%、95.65%,特异度分别为91.30%、82.35%。三者联合鉴别PA与MT的AUC可提高至0.98,敏感度为100.00%,特异度为86.96%。结论ASL联合DTI有助于鉴别诊断腮腺良恶性肿瘤,综合运用多参数各优势有助于区分WT、PA和MT。联合有差异的参数可显著提高区分PA与MT的诊断效能。

关键词：腮腺肿瘤 Warthin瘤多形性腺瘤恶性肿瘤动脉自旋标记成像扩散张量成像磁共振成像

SeBROP:blind ROP attacks without returns

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Frontiers of Computer Science 2022年第4期16卷 185-202页

作者： Tianning zhang Miao Cai diming zhang Hao Huang Department of Computer Science and Technology Nanjing UniversityNanjing210023China School of Computer and Information Hohai UniversityNanjing211106China College of Computer Engineering Jiangsu University of Science and TechnologyZhenjiang212008China

Currently,security-critical server programs are well protected by various defense techniques,such as Address Space Layout Randomization(ASLR),eXecute Only Memory(XOM),and Data Execution Prevention(DEP),against modern code-reuse attacks like Return-oriented Programming(ROP)***,in these victim programs,most syscall instructions lack the following ret instructions,which prevents attacks to stitch multiple system calls to implement advanced behaviors like launching a remote *** this kind of gadget greatly constrains the capability of code-reuse *** paper proposes a novel code-reuse attack method called Signal Enhanced Blind Return Oriented Programming(SeBROP)to address these *** SeBROP can initiate a successful exploit to server-side programs using only a stack overflow *** leveraging a side-channel that exists in the victim program,we show how to find a variety of gadgets blindly without any pre-knowledges or reading/disassembling the code ***,we propose a technique that exploits the current vulnerable signal checking mechanism to realize the execution flow control even when ret instructions are *** technique can stitch a number of system calls without returns,which is more superior to conventional ROP ***,the SeBROP attack precisely identifies many useful gadgets to constitute a Turing-complete *** attack can defeat almost all state-of-the-art defense *** SeBROP attack is compatible with both modern 64-bit and 32-bit *** validate its effectiveness,We craft three exploits of the SeBROP attack for three real-world applications,i.e.,32-bit Apache 1.3.49,32-bit ProFTPD 1.3.0,and 64-bit Nginx *** results demonstrate that the SeBROP attack can successfully spawn a remote shell on Nginx,ProFTPD,and Apache with less than 8500/4300/2100 requests,respectively.

关键词： code-reuse atack ROP signal

PENALTY　UPWIND　FINITE　ELEMENT　METHOD　FOR　DIFFUSIVE　CONVECTION　PROBLEM　IN　DOUBLE－DIFFUSIVE　SYSTEM

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Journal of Hydrodynamics 1995年第4期7卷 63-71页

作者： zhang, diming Chen, Hong Li, Lin Zhongshan Univ Guangzhou China

A penalty function upwind finite element method is describe in this paper for diffusive convection problem in temperature and salinity double-diffusive system. With good stability and two-order accuracy, the method was directly employed to the original equations,and tested in a square cavity with constant lateral heating. The steady-state results are approximate to the tendency of the time-dependent results by pressure-velocity (PV) coupling method. Nunerical simulation in a square cavity with adiabatic baffle and constant lateral heating was achieved with distribution of stream function, temperature and concentration isocontours under Thermal Raleigh Number Re= 106 and the thermal buoyancy ratio covering the ramp of N = 1, 3, 5, 7. Meanwhile, the effects of N and the adiabatic baffle to the fluid field were ho discussed.

关键词： temperature-Salinity double-diffusive system penalty upwind finite element method diffusive convection

Influence of Mixture Gas Conditions on the Laminar Combustion Characteristics of Natural Gas

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Journal of Thermal Science 2024年第3期33卷 1231-1241页

作者： LOU diming ZHU Kan zhang Yunhua REN Yedi TAN Piqiang FANG Liang FAN Lanlan School of Automotive Studies Tongji UniversityShanghai201804China Ji’nan Power Co.Ltd Sinotruk GroupJi’nan250200China

Natural gas is a promising alternative fuel for the internal combustion engine,and natural gas engine has become an efficient and feasible measure to deal with the energy shortage and climate *** the laminar flame characteristics are the foundation of the turbulent flame,the laminar flame characteristics of natural gas have a significant impact on the combustion status and efficiency of the engine.A visual constant volume bomb was used to study the influence of the gas components,different excess air coefficient(λ),and initial conditions on the laminar combustion characteristics of natural *** experimental results showed that when the initial pressure and temperature were 0.1 MPa and 300 K respectively,compared to propane,ethane had a remarkable influence on the equivalent-combustion laminar-combustion-speed,with an average increase of approximately 5.1%for every 2.5%increase in the ethane *** laminar combustion velocity of the natural gas under different excess air coefficients had a maximum value at aboutλ=1.0,and the Markstein length of the flame decreased with the increase of theλ.The increase in the initial pressure of the mixture resulted in a decrease in the equivalent-combustion laminar-combustion-speed of the flame,a significant decrease in the Markstein *** increase of the initial temperature of the mixture led to a rapid increase of the equivalent-combustion laminar-combustion-speed,but the effect on the flame Markstein length was not dominant.

关键词： constant volume bomb natural gas engine combustion characteristics laminar combustion velocity Markstein length

VBMq： pursuit baremetal performance by embracing block I/O parallelism in virtualization

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Frontiers of Computer Science 2018年第5期12卷 873-886页

作者： diming zhang Fei XUE Hao HUANG Shaodi YOU Faculty of Computer Science and Technology Nanjing University Nanjing 210023 China College of Computer Science and Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China College of Engineering and Computer Science Australian National University Canberra 2600 Australia Data61-CSIRO Australian National University Canberra 2600 Australia

Barely acceptable block I/O performance prevents virtualization from being widely used in the HighPerformance Computing field. Although the virtio paravirtual framework brings great I/O performance improvement, there is a sharp performance degradation when accessing high-performance NAND-flash-based devices in the virtual machine due to their data parallel design. The primary cause of this fact is the deficiency of block I/O parallelism in hypervisor, such as KVM and Xen. In this paper, we propose a novel design of block I/O layer for virtualization, named VBMq. VBMq is based on virtio paravirtual I/O model, aiming to solve the block I/O parallelism issue in virtualization. It uses multiple dedicated I/O threads to handle I/O requests in parallel. In the meanwhile, we use polling mechanism to alleviate overheads caused by the frequent context switches of the VM＇s notification to and from its hypervisor. Each dedicated I/O thread is assigned to a non-ovedapping core to improve performance by avoiding unnecessary scheduling. In addition, we configure CPU affinity to optimize I/O completion for each request. The CPU affinity setting is very helpful to reduce CPU cache miss rate and increase CPU efficiency. The prototype system is based on Linux 4.1 kernel and QEMU 2.3.1. Our measurements show that the proposed method scales graciously in the multi-core environment, and provides performance which is 39.6x better than the baseline at most, and approaches bare-metal performance.

关键词： high-performance parallelism paravirtual I/O

Peptide Functionalized Nanoplasmonic Sensor for Explosive Detection

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Nano-Micro Letters 2016年第1期8卷 36-43页

作者： diming zhang Qian zhang Yanli Lu Yao Yao Shuang Li Jing Jiang Gang Logan Liu Qingjun Liu Biosensor National Special Laboratory Key Laboratory for Biomedical Engineering of Education Ministry Department of Biomedical Engineering Zhejiang University Micro and Nanotechnology Lab University of Illinois at Urbana-Champaign

In this study, a nanobiosensor for detecting explosives was developed, in which the peptide was synthesized with trinitrotoluene(TNT)-specific sequence and immobilized on nanodevice by Au–S covalent linkage, and the nanocup arrays were fabricated by nanoimprint and deposited with Au nanoparticles to generate localized surface plasmon resonance(LSPR). The device was used to monitor slight change from specific binding of 2,4,6-TNT to the peptide. With high refractive index sensing of ~10~4nm/RIU, the nanocup device can detect the binding of TNT at concentration as low as3.12×10^(-7)mg mL^(-1) by optical transmission spectrum modulated by LSPR. The nanosensor is also able to distinguish TNT from analogs of 2,4-dinitrotoluene and 3-nitrotoluene in the mixture with great selectivity. The peptide-based nanosensor provides novel approaches to design versatile biosensor assays by LSPR for chemical molecules.

关键词： Nanocup arrays Peptide 2,4,6-trinitrotoluene(TNT) Localized surface plasmon resonance(LSPR) Nanosensor

A biosensing system using a multiparameter nonlinear dynamic analysis of cardiomyocyte beating for drug-induced arrhythmia recognition

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Microsystems & Nanoengineering 2022年第3期8卷 277-290页

作者： Hao Wang Yue Wu Quchao Zou Wenjian Yang Zhongyuan Xu Hao Dong Zhjing Zhu Depeng Wang Tanxing Wang Ning Hu diming zhang State Key Laboratory of Optoelectronic Materials and Technologies Guangdong Province Key Laboratory of Display Material and TechnologySchool of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou 510006China Research Center for Itelligent Sensing Systems Zhejiang LabHangzhou 311121China ZJU-Hangzhou Global Scientific and Technological Innovation Center Department of ChemistryThe Second Affiliated Hospital Zhejiang University School of MedicineDepartment of Clinical Medical EngineeringZhejiang UniversityHangzhou 310058China Key Laboratory of Novel Target and Drug Study for Neural Repair of Zhejang Province School of MedicineSchool of Computer&Computing ScienceZhejiang University City CollegeHangzhou 310015China School of Brain Science and Brain Medicine Zhejiang UniversityHangzhou 310058China College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China E-LinkCare Meditech Co LtdHangzhou 310011China State Key Laboratory of Transducer Technology Chinese Academy of SciencesShanghai 200050China

Cardiovascular disease is the number one cause of death in ***,cardiotoxicity is one of the most important adverse effects assessed by arrhythmia recognition in drug ***,cell-based techniques developed for arhythmia recognition primarily employ linear methods such as time-domain analysis that detect and compare individual waveforms and thus fall short in some applications that require automated and efficient arrhythmia recognition from large *** carried out the frst report to develop a biosensing system that integrated impedance measurement and multiparameter nonlinear dynamic algorithm(MNDA)analysis for druginduced arrhythmia recognition and *** biosensing system cultured cardiomyocytes as physiologically relevant models,used interdigitated electrodes to detect the mechanical beating of the cardiomyocytes,and employed MNDA analysis to recognize drug-induced arrhythmia from the cardiomyocyte beating *** best performing MNDA parameter,approximate entropy,enabled the system to recognize the appearance of sertindoleand norepinephrine-induced arrhythmia in the *** MNDA reconstruction in phase space enabled the system to classify the different arrhythmias and quantify the severity of *** new biosensing system utilizing MNDA provides a promising and alternative method for drug-induced arrhythmia recognition and classification in cardiological and pharmaceutical applications.

关键词： arrhythmia cardio analysis

A biosensing system employing nanowell microelectrode arrays to record the intracellular potential of a single cardiomyocyte

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Microsystems & Nanoengineering 2022年第3期8卷 185-198页

作者： Yuting Xiang Haitao Liu Wenjian Yang Zhongyuan xu Yue Wu Zhajian Tang Zhjing Zhu Zhiyong Zeng Depeng Wang Tianxing Wang Ning Hu diming zhang Department of Obstetrics and Gynecology Affiliated Dongguan People's HospitalSouthern Medical UniversityDongguan 523058China Research Center for Inelligent Sensing Systems Zhejiang LaboratoryHangzhou 311100China Research Center for Humanoid Sensing Zhejiang LaboratoryHangzhou 311100China Key Laboratory of Novel Target and Drug Study for Neural Repair of Zhejiang Province School of MedicineSchool of Computer&Computing ScienceZhejiang University City CollegeHangzhou 310015China School of Brain Science and Brain Medicine Zhejiang UniversityHangzhou 310058China School of Automation Nanjing University of Science and TechnologyNanjing 210094China College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China E-Link Care Meditech Co. LtdHangzhou 310011China ZJU-Hangzhou Global Scientific and Technological Innovation Center Department of ChemitryZhejiang UniversityHangzhou 310058China

Electrophysiological recording is a widely used method to investigate cardiovascular pathology,pharmacology and developmental *** arrays record the electrical potential of cells in a minimally invasive and highthroughput ***,commonly used microelectrode arays primarily employ planar microelectrodes and cannot work in applications that require a recording of the intracellular action potential of a single *** this study,we proposed a novel measuring method that is able to record the intracellular action potential of a single cardiomyocyte by using a nanowell patterned microelectrode array(NWMEA).The NWMEA consists of five nanoscale wells at the center of each circular planar *** pulse electroporation was applied to the NWMEA to penetrate the cardiomyocyte membrane,and the intracellular action potential was continuously *** intracellular potential recording of cardiomyocytes by the NWMEA measured a potential signal with a higher quality(213.76±25.85%),reduced noise root-mean-square(~33%),and higher signal-to-noise ratio(254.36±12.61%)when compared to those of the extracellular *** to previously reported nanopillar microelectrodes,the NWMEA could ensure single cell electroporation and acquire high-quality action potential of cardiomyocytes with reduced fabrication *** NWMEA-based biosensing system is a promising tool to record the intracellular action potential of a single cell to broaden the usage of microelectrode arrays in electrophysiological investigation.

关键词： arrays potential record

PROBLEMS ON COMPUTING SHALLOW WATER CIRCULATION AND SIMULATING THE FLOW PAST ISLANDS IN NEARSHORE WATER

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Journal of Hydrodynamics 1989年第1期1卷 8-14页

作者： zhang diming CHENG LIANGGUI, Department of Mechanics, Zhongshan University, Guangzhou,P.R. China

This paper continues discussing the problems of numerically solving the shallow water circulation on the basis of ref. 1, For the numerical method proposed in ref. 1, we applied a storage method with dense matrices, which abandoned usual bandwidth concept and attained the intention of saving interior storage, computing time and amount of preparing work before computing. The circulation considered the effect of small islands was successfully simulated by specially dealing with the bottom friction terms and the boundary conditions. In addition, we discussed the action of bottom friction on the dissipation of tidal energy and its effect on stability of period motion.

关键词： PROBLEMS ON COMPUTING SHALLOW WATER CIRCULATION AND SIMULATING THE FLOW PAST ISLANDS IN NEARSHORE WATER