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Stellar spectra association rule mining method based on the weighted frequent pattern tree

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Research in Astronomy and Astrophysics 2013年第3期13卷 334-342页

作者： jiang-hui cai Xu-Jun Zhao Shi-Wei Sun Ji-Fu Zhang Hai-Feng Yang School of Computer Science and Technology Taiyuan University of Science and Technology National Astronomical Observatories Chinese Academy of Sciences

Effective extraction of data association rules can provide a reliable basis for classification of stellar spectra. The concept of stellar spectrum weighted itemsets and stellar spectrum weighted association rules are introduced, and the weight of a single property in the stellar spectrum is determined by information entropy. On that basis, a method is presented to mine the association rules of a stellar spectrum based on the weighted frequent pattern tree. Important properties of the spectral line are highlighted using this method. At the same time, the waveform of the whole spectrum is taken into account. The experimental results show that the data association rules of a stellar spectrum mined with this method are consistent with the main features of stellar spectral types.

关键词： methods: data analysis -- stars: fundamental parameters -- techniques:spectroscopic -- astronomical data bases: miscellaneous

A comprehensive fluid-solid coupling dynamic simulation for spatiotemporal distribution of regression rate in hybrid rocket motors

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Chinese Journal of Aeronautics 2024年第9期37卷 100-112页

作者： Tianfang WEI Guobiao cai hui TIAN Xiangyu MENG Xianzhu jiang Xiaoming GU School of Astronautics Beihang UniversityBeijing 100191China Key Laboratory of Spacecraft Design Optimization&Dynamic Simulation Technologies Ministry of Education Beijing 100191China

The spatiotemporal distribution characteristics of the regression rate are crucial aspects of the research on Hybrid Rocket Motor(HRM).This study presents a pioneering effort in achiev-ing a comprehensive numerical simulation of fluid dynamics and heat transfer in both the fluid and solid regions throughout the entire operation of an *** accomplish this,a dynamic grid tech-nique that incorporates fluid-solid coupling is *** validate the precision of the numerical simulations,a firing test is conducted,with embedded thermocouple probes being used to measure the inner temperature of the fuel *** temperature variations in the solid fuel obtained from both experiment and simulations show good *** maximum combustion temperature and average thrust obtained from the simulations are found to deviate from the experimental results by only 3.3%and 2.4%,***,it can be demonstrated that transient numerical simu-lations accurately capture the fluid-solid coupling characteristics and transient regression *** dynamic simulation results of inner flow field and solid region throughout the entire working stage reveal that the presence of vortices enhances the blending of combustion gases and improves the regression rate at both the front and rear ends of the fuel *** addition,oscillations of the regression rate obtained in the simulation can also be well corresponded with the corrugated surface observed in the ***,the zero-dimension regression rate formula and the for-mula describing the axial location dependence of the regression rate are fitted from the simulation results,with the corresponding coefficients of determination(R°)of 0.9765 and 0.9298,*** research serves as a reference for predicting the performance of HRM with gas oxygen and polyethylene,and presents a credible way for investigating the spatiotemporal distribution of the regression rate.

关键词： Hybrid Rocket Motor(HRM) Transient numerical simulation Fluid-solid couplingheat transfer Spatiotemporal distribution of regression rate Dynamic grid

Development of sympathetic ophthalmia following globe injury

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Chinese Medical Journal 2009年第24期122卷 2961-2966页

作者： ZHANG Ying ZHANG Mao-nian jiang cai-hui YAO Yi Department of Ophthalmology Chinese PLA General HospitalBeijing 100853 China

Background Sympathetic ophthalmia （SO）, a rare, bilateral, diffuse granulomatous uveitis, usually occurs after open globe injury or intraocular surgery. We sought to identify the risk factors for the development of SO after open globe injury and describe their demographic and clinical features and outcomes of treatments. Methods A retrospective study of inpatients with globe injury in 15 tertiary referral hospitals of China from January 2001 to December 2005 was conducted. The information of demography, nature and mechanism of injury, time and ways of treatments and outcomes was reviewed. Diagnosis of SO was made based on a history of ocular trauma or surgery and subsequent development of bilateral or contralateral uveitis consistent with SO. Any association between related parameters and development of SO was analyzed. Results Among 9103 patients （9776 eyes） of globe injury, SO occurred after open globe injury in 18 cases with an occurrence rate of 0.37%, vitrectomy of closed globe injury in 2 （0.37%） and perforation of burned eyes in another 2. For open globe injury, the median age （（36.72±13.59） years, P=0.01） was higher in patients with SO; there were no significant effects of sexes, injury type, uvea proplaps, once or multi-intraocular surgery, once or multi-vitrectomy and endophthalmitis on incidence of SO; 0.70% endophthalmitis concurred with SO; 83.33% of SO occurred within 1 year after injury or last ocular surgery. SO developed in a fellow eye one week after evisceration of the perforating burned eye. Good final visual acuity was obtained in sympathizing eyes with prompt treatment. Conclusions For open globe injuries, SO sufferers were relatively older and any injury type could induce SO with equal possibility. The initial open globe injury was more likely to be the trigger of SO than subsequent intraocular surgeries including vitrectomy. Prophylactic enucleation after injury is not recommended.

关键词： sympathetic ophthalmia eye injury intraocular sugery risk factors

Automatic Requirement Dependency Extraction Based on Integrated Active Learning Strategies

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Machine Intelligence Research 2024年第5期21卷 993-1010页

作者： hui Guan Guorong cai Hang Xu Department of Computer Science and Technology Shenyang University of Chemical TechnologyShenyang110142China Key Laboratory of Industrial Intelligence Technology on Chemical Process Shenyang110142China

Since requirement dependency extraction is a cognitively challenging and error-prone task,this paper proposes an automatic requirement dependency extraction method based on integrated active learning *** this paper,the coefficient of variation method was used to determine the corresponding weight of the impact factors from three different angles:uncertainty probability,text similarity difference degree and active learning variant prediction divergence *** combining the three factors with the proposed calculation formula to measure the information value of dependency pairs,the top K dependency pairs with the highest comprehensive evaluation value are selected as the optimal *** the optimal samples are continuously added into the initial training set,the performance of the active learning model using different dependency features for requirement dependency extraction is rapidly ***,compared with other active learning strategies,a higher evaluation measure of requirement dependency extraction can be achieved by using the same number of ***,the proposed method using the PV-DM dependency feature improves the weight-F1 by 2.71%,the weight-recall by 2.45%,and the weight-precision by 2.64%in comparison with other strategies,saving approximately 46%of the labelled data compared with the machine learning approach.

关键词： Requirement dependency dependency extraction dependency features integrated active learning strategies coefficient of variation

Combined effects of ultrasonic vibration and FeCoNiCrCu coating on interfacial microstructure and mechanical properties of Al/Mg bimetal by compound casting

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China Foundry 2024年第5期21卷 588-598页

作者： Yuan-cai Xu Wen-ming jiang Qing-qing Li Ling-hui Yu Xiao-peng Yu Zi-tian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

In this work,a new treatment method combining ultrasonic vibration with FeCoNiCrCu high entropy alloy(HEA)coating was used to prepared Al/Mg bimetal through the lost foam compound *** effects of composite treatment involving ultrasonic vibration and HEA coating on interfacial microstructure and mechanical properties of Al/Mg bimetal were *** demonstrate that the interface thickness of the Al/Mg bimetal with composite treatment significantly decreases to only 26.99%of the thickness observed in the untreated Al/Mg *** HEA coating hinders the diffusion between Al and Mg,resulting the significant reduction in Al/Mg intermetallic compounds in the *** Al/Mg bimetal interface with composite treatment is composed of Al_(3)Mg_(2)and Mg_(2)Si/AlxFeCoNiCrCu+FeCoNiCrCu/δ-Mg+Al_(12)Mg_(17)eutectic *** interface resulting from the composite treatment has a lower hardness than that without *** acoustic cavitation and acoustic streaming effects generated by ultrasonic vibration promote the diffusion of Al elements within the HEA coating,resulting in a significant improvement in the metallurgical bonding quality on the Mg *** fracture position shifts from the Mg side of the Al/Mg bimetal only with HEA coating to the Al side with composite *** shear strength of the Al/Mg bimetal increases from 32.16 MPa without treatment to 63.44 MPa with ultrasonic vibration and HEA coating,increasing by 97.26%.

关键词： ultrasonic vibration FeCoNiCrCu HEA coating Al/Mg bimetal interfacial microstructure shear strength compound casting

N-Heterocyclic carbene-catalyzed enantioselective(dynamic) kinetic resolutions and desymmetrizations

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Science China Chemistry 2024年第2期67卷 482-511页

作者： Yi Zhang hui cai Xiuhai Gan Zhichao Jin National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityHuaxi DistrictGuiyang550025China

N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically *** content is organized according to the activation modes involved i... 详细信息

关键词： N-heterocyclic carbene kinetic resolution dynamic kinetic resolution desymmetrization organocatalysis

Disentangling distinct Cu surface sites for electrocatalytic CO_(2)-to-CO and CO-to-C_(2+)conversion

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Science China Chemistry 2024年第4期67卷 1047-1048页

作者： Kun jiang Wen-Bin cai Interdisciplinary Science Research Centre School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Collaborative Innovation Center of Chemistry for Energy MaterialsDepartment of ChemistryFudan UniversityShanghai 200438China

Electrochemical CO_(2)reduction reaction(CO_(2)RR)is a promising strategy to curb anthropogenic carbon emissions,for which intermittent renewable electricity could be stored as chemical energy within carbon-based fuel... 详细信息

关键词： carbon Electrochemical surface

Heterometallic Mg-Ni-Mg Complex Promoted Hydrosilylation of Alkenes: Catalytic Performance and Intermediates Characterization

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Chinese Journal of Chemistry 2024年第18期42卷 2133-2139页

作者： Yanping cai Shengjie jiang Xin Xu Key Laboratory of Organic Synthesis of jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochowUniversitySuzhouJiangsu215123China

Background and Originality Content The catalytic hydrosilylation of unsaturated hydrocarbons,facilitated by transition metal(TM),is widely recognized as a proficient technique for the synthesis of high-value organosilicon compounds'ti-4l over the past few decades,the most dominant *** in hydrosilylation processes have been constituted by pre-Ccious metar complexesroceinerecent vears omore sustainabile earth-abundant metal catalysts have received increased attentionj2-14l The classcal mechanism of transition metal-catalyzed hydrosilylation is generally accomplished through a series of fundamental processes(Scheme 1a),including(i)coordination and oxidative addition of Si-H bond to a low-valent metal center to form e.g.,o-complex or silyl metal hydride;(ii)insertion of.C-C multipe bonds intometal-hdridelsior metal-silicon bond;jiol and(ii)reductive elimination that forwards the hydrosilylated product with Markovnikov or anti-Markovnikov selectivity.

关键词： Heterometallic complex Cooperative effect Hydrosilylation Magnesium Nickel hydride

Adversarial attacks against dynamic graph neural networks via node injection

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High-Confidence Computing 2024年第1期4卷 43-51页

作者： Yanan jiang hui Xia School of Computer Science and Technology Ocean University of ChinaQingdao 266100China

Dynamic graph neural networks(DGNNs)have demonstrated their extraordinary value in many practical ***,the vulnerability of DNNs is a serious hidden danger as a small disturbance added to the model can markedly reduce its *** the same time,current adversarial attack schemes are implemented on static graphs,and the variability of attack models prevents these schemes from transferring to dynamic *** this paper,we use the diffused attack of node injection to attack the DGNNs,and first propose the node injection attack based on structural fragility against DGNNs,named Structural Fragility-based Dynamic Graph Node Injection Attack(SFIA).SFIA firstly determines the target time based on the period ***,it introduces a structural fragile edge selection strategy to establish the target nodes set and link them with the malicious node using serial ***,an optimization function is designed to generate adversarial features for malicious *** on datasets from four different fields show that SFIA is significantly superior to many comparative *** the graph is injected with 1%of the original total number of nodes through SFIA,the link prediction Recall and MRR of the target DGNN link decrease by 17.4%and 14.3%respectively,and the accuracy of node classification decreases by 8.7%.

关键词： Dynamic graph neural network Adversarial attack Malicious node Vulnerability