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Dimensional Results for Cartesian Products of Homogeneous Moran Sets

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Acta Mathematicae Applicatae Sinica 2012年第4期28卷 673-680页

作者： Li CAO xing-gang he School of Mathematics and Statistics Wuhan University College of Mathematics and Statistics Central China Normal University

M（J, {ms ＊ ns}, {Cs}） be the collection of Cartesian products of two homogenous Moran sets with the same ratios {cs} Where J = [0, 1] × [0, 1]. Then the maximal and minimal values of the Hausdorff dimensions for t... 详细信息

关键词： Homogeneous Moran sets Cartesian product Hausdorff dimension

Research on the influences of motion characteristics of jetting projectile charge under water

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Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： xing Chen Yong-gang Lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater *** paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in *** findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying *** the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the *** optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in *** density plays a crucial role in the velocity decay pattern of the JPC during *** with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are ***,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge ***,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

Bunch-length measurement at a bunch-by-bunch rate based on time–frequency-domain joint analysis techniques and its application

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Nuclear Science and Techniques 2024年第4期35卷 165-175页

作者： Hong-Shuang Wang xing Yang Yong-Bin Leng Yi-Mei Zhou Ji-gang Wang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

This paper presents a new technique for measuring the bunch length of a high-energy electron beam at a bunch-by-bunch rate in storage *** technique uses the time–frequency-domain joint analysis of the bunch signal to obtain bunch-by-bunch and turn-by-turn longitudinal parameters,such as bunch length and synchronous *** bunch signal is obtained using a button electrode with a bandwidth of several *** data acquisition device was a high-speed digital oscilloscope with a sampling rate of more than 10 GS/s,and the single-shot sampling data buffer covered thousands of *** bunch-length and synchronous phase information were extracted via offline calculations using Python *** calibration coefficient of the system was determined using a commercial streak ***,this technique was tested on two different storage rings and successfully captured various longitudinal transient processes during the harmonic cavity debugging process at the Shanghai Synchrotron Radiation Facility(SSRF),and longitudinal instabilities were observed during the single-bunch accumulation process at hefei Light Source(HLS).For Gaussian-distribution bunches,the uncertainty of the bunch phase obtained using this technique was better than 0.2 ps,and the bunch-length uncertainty was better than 1 *** dynamic range exceeded 10 *** technology is a powerful and versatile beam diagnostic tool that can be conveniently deployed in high-energy electron storage rings.

关键词： Bunch-by-bunch diagnostic Bunch-length measurement Synchronous phase measurement Joint time–frequency-domain analysis Longitudinal instability

Improving flangeability of multiphase steel by increasing microstructural homogeneity

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1736-1745页

作者： Xiao-yu Yang Yong-gang Yang xing Fang Han-long Zhang Zhen-li Mi Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Engineering TechnologyUniversity of Science and Technology BeijingBeijing 100083China Shanghai Baosteel Group Corp.Technology Center Shanghai 201900China

Multiphase microstructure significantly increases the strength,usually at the expense of flangeability because of lacking microstructure *** further improve the strength-flangeability of multiphase steel,the microstructural homogeneity was advanced by adjusting the hard martensite/austenite(M/A)*** strength-flangeability was measured via uniaxial tensile tests and hole expansion *** microstructures were characterized using a scanning electron microscope equipped with an electron backscatter diffraction detector and a transmission electron *** tests were supplementally used to quantitatively reveal the microstructural homogeneity of the *** show that the adjusted multiphase steel achieves an excellent ultimate tensile strength(~800 MPa)and flangeability(~135%hole expansion ratio).A promising homogeneous multiphase microstructure was obtained by controlling undercooled austenite transformed at about 600℃.This microstructure consists of soft polygonal ferrite,blocky bainitic ferrite,and hard M/A *** volume fraction of M/A islands is around 5%,and the average size is less than l *** nanoindentation analysis indicated that the participation of M/A islands impressively influenced the microstructural *** strain partition and better mechanical compatibility were present in the adjusted multiphase steel since the plasticity initiation started late,which resulted in a positive ***,avoiding M/A islands distributed in the chain along the rolling direction on the matrix hindered the possibility of voids coalescing into cracks and stabilized the flanging performance.

关键词： Multiphase steel Flangeability Martensite/austenite island-Microstructural homogeneity-Microstructure Compact strip production process

Intelligent geochemical interpretation of mass chromatograms:Based on convolution neural network

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Petroleum Science 2024年第2期21卷 752-764页

作者： Kai-Ming Su Jun-gang Lu Jian Yu Zi-xing Lu Shi-Jia Chen Hubei Key Laboratory of Petroleum Geochemistry and Environment Wuhan430100HubeiChina College of Resources and Environment Yangtze UniversityWuhan430100HubeiChina School of Geoscience and Technology Southwest Petroleum UniversityChengdu610500SichuanChina Changqing Oilfield Company PetroChinaXi'an710021ShaanxiChina

Gas chromatography-mass spectrometry(GC-MS)is an extremely important analytical technique that is widely used in organic *** is the only approach to capture biomarker features of organic matter and provides the key evidence for oil-source correlation and thermal maturity ***,the conventional way of processing and interpreting the mass chromatogram is both timeconsuming and labor-intensive,which increases the research cost and restrains extensive applications of this *** overcome this limitation,a correlation model is developed based on the convolution neural network(CNN)to link the mass chromatogram and biomarker features of samples from the Triassic Yanchang Formation,Ordos Basin,*** this way,the mass chromatogram can be automatically *** research first performs dimensionality reduction for 15 biomarker parameters via the factor analysis and then quantifies the biomarker features using two indexes(*** and PMI)that represent the organic matter thermal maturity and parent material type,***,training,interpretation,and validation are performed multiple times using different CNN models to optimize the model structure and hyper-parameter setting,with the mass chromatogram used as the input and the obtained MI and PMI values for supervision(label).The optimized model presents high accuracy in automatically interpreting the mass chromatogram,with R2values typically above 0.85 and0.80 for the thermal maturity and parent material interpretation results,*** significance of this research is twofold:(i)developing an efficient technique for geochemical research;(ii)more importantly,demonstrating the potential of artificial intelligence in organic geochemistry and providing vital references for future related studies.

关键词： Organic geochemistry Biomarker Mass chromatographic analysis Automated interpretation Convolution neural network Machine learning

Novel fluorene-carzazole-based conjugated copolymers containing pyrazoline and benzothiazole segments for blue light-emitting materials

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Chinese Chemical Letters 2007年第12期18卷 1496-1500页

作者： Hao Chen xing Xu he gang Yan Xian Rong Cai Ying Li Qing Jiang Ming Gui Xie College of Chemistry Sichuan University Chengdu 610064 China

A series of novel fluorene-carbazole-based copolymers with pyrazoline and benzothiazole units were synthesized successfully through Suzuki coupling reactions. The molecular structures and thermal properties of these polymers were characterized by FTrIR, 1H NMR, DSC and TGA. GPC results indicated that the weight-average molecular weight （Mw） and polydispersity of these polymers were in range （12,0（0）-14,000） and （1.8-2.0）, respectively. The two resulting polymers have high photoluminescence quantum efficiency implying that they may be promising candidates for polymer light-emitting diodes （PLEDs）.

关键词： Fluorene-carbazole copolymers Pyrazoline Bezothiazole

Impact of open hepatectomy on postoperative bile leakage in patients with biliary tract cancer

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 67-75页

作者： gang Wu Wen-Ying Li Yu-xing Gong Feng Lin Chen Sun General Surgery Department The Second Affiliated Hospital of Harbin Medical UniversityHarbin 150000Heilongjiang ProvinceChina

BACKGROUND Bile leakage is a common and serious complication of open hepatectomy for the treatment of biliary tract *** To evaluate the incidence,risk factors,and management of bile leakage after open hepatectomy in patients with biliary tract *** We retrospectively analyzed 120 patients who underwent open hepatectomy for biliary tract cancer from February 2018 to February *** leak was defined as bile drainage from the surgical site or drain or the presence of a biloma on *** incidence,severity,timing,location,and treatment of the bile leaks were *** risk factors for bile leakage were analyzed using univariate and multivariate logistic regression *** The incidence of bile leak was 16.7%(20/120),and most cases were grade A(75%,15/20)according to the International Study Group of Liver Surgery *** median time of onset was 5 d(range,1-14 d),and the median duration was 7 d(range,2-28 d).The most common location of bile leakage was the cut surface of the liver(70%,14/20),followed by the anastomosis site(25%,5/20)and the cystic duct stump(5%,1/20).Most bile leaks were treated conservatively with drainage,antibiotics,and nutritional support(85%,17/20),whereas some required endoscopic retrograde cholangiopancreatography with stenting(10%,2/20)or percutaneous transhepatic cholangiography with drainage(5%,1/20).Risk factors for bile leakage include male sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood *** Bile leakage is a frequent complication of open hepatectomy for biliary tract ***,most cases are mild and can be conservatively *** sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood transfusion were associated with an increased risk of bile leak.

关键词： Open hepatectomy Bile leak Biliary tract cancer Risk factors Management Complication

Wavelength-interval switchable Brillouin–Raman random fiber laser through Brillouin pump manipulation

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Chinese Physics B 2024年第7期33卷 374-379页

作者：李阳徐恩明陈睿佳 Yu-gang Shee 张祖兴 Advanced Photonic Technology Laboratory College of Electronic and Optical Engineering&College of MicroelectronicsNanjing University of Posts and TelecommunicationsNanjing 210023China Department of Electrical and Electronic Engineering Lee Kong Chian Faculty of Engineering&Science(LKC FES)Universiti Tunku Abdul Rahman(UTAR)Sungai Long CampusMalaysia

A wavelength-interval switchable Brillouin–Raman random fiber laser(BRRFL) based on Brillouin pump(BP) manipulation is proposed in this paper. The proposed wavelength-interval switchable BRRFL has a full-open cavity configuration, featuring multiwavelength output with wavelength interval of double Brillouin frequency shifts. Through simultaneously injecting the BP light and its first-order stimulated Brillouin-scattered light into the cavity, the laser output exhibits a wavelength interval of single Brillouin frequency shift. The wavelength-interval switching effect can be manipulated by controlling the power of the first-order stimulated Brillouin scattering light. The experimental results show the multiwavelength output can be switched between double Brillouin frequency shift multiwavelength emission with a broad bandwidth of approximately 60 nm and single Brillouin frequency shift multiwavelength emission of 44 nm. The flexible optically controlled random fiber laser with switchable wavelength interval makes it useful for a wide range of applications and holds significant potential in the field of wavelength-division multiplexing optical communication.

关键词： wavelength-interval switchable fiber laser Brillouin fiber laser stimulated Brillouin-scattered random fiber laser

Ascertaining the influences of auxiliary qubits on the Einstein–Podolsky–Rosen steering and its directions

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Chinese Physics B 2024年第5期33卷 213-221页

作者：邢玲玲杨欢张刚孔敏 School of Electrical and Photoelectronic Engineering West Anhui UniversityLu'an 237012China

Einstein–Podolsky–Rosen(EPR) steering is an example of nontrivial quantum nonlocality and characteristic in the non-classical *** directivity(or asymmetry) is a fascinating trait of EPR steering,and it is different from other quantum ***,we consider the strategy in which two atoms compose a two-qubit X state,and the two atoms are owned by Alice and Bob,*** atom of Alice suffers from a reservoir,and the atom of Bob couples with a bit flip *** influences of auxiliary qubits on EPR steering and its directions are revealed by means of the entropy uncertainty *** results indicate that EPR steering declines with growing time t when adding fewer auxiliary *** EPR steering behaves as damped oscillation when introducing more auxiliary qubits in the strong coupling *** the weak coupling regime,the EPR steering monotonously decreases as t increases when coupling auxiliary *** increases in auxiliary qubits are responsible for the fact that the steerability from Alice to Bob(or from Bob to Alice) can be more effectively ***,the introductions of more auxiliary qubits can change the situation that steerability from Alice to Bob is certain to a situation in which steerability from Bob to Alice is certain.

关键词： auxiliary qubits EPR steering directions influence