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Unstructured Big Data Threat Intelligence Parallel Mining Algorithm

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Big Data Mining and Analytics 2024年第2期7卷 531-546页

作者： Zhihua Li Xinye yu tao wei Junhao Qian School of Artificial Intelligence and Computer Science Jiangnan UniversityWuxi 214122China School of IoT Engineering Jiangnan UniversityWuxi 214122China

To efficiently mine threat intelligence from the vast array of open-source cybersecurity analysis reports on the web,we have developed the Parallel Deep Forest-based Multi-Label Classification(PDFMLC)***,open-source cybersecurity analysis reports are collected and converted into a standardized text ***,five tactics category labels are annotated,creating a multi-label dataset for tactics *** the limitations of low execution efficiency and scalability in the sequential deep forest algorithm,our PDFMLC algorithm employs broadcast variables and the Lempel-Ziv-Welch(LZW)algorithm,significantly enhancing its acceleration ***,our proposed PDFMLC algorithm incorporates label mutual information from the established dataset as input *** captures latent label associations,significantly improving classification ***,we present the PDFMLC-based Threat Intelligence Mining(PDFMLC-TIM)*** results demonstrate that the PDFMLC algorithm exhibits exceptional node scalability and execution ***,the PDFMLC-TIM method proficiently conducts text classification on cybersecurity analysis reports,extracting tactics entities to construct comprehensive threat *** a result,successfully formatted STIX2.1 threat intelligence is established.

关键词： unstructured big data mining parallel deep forest multi-label classification algorithm threat intelligence

Synthesis and Characteristics of Fe_3C Nanoparticles Embedded in Amorphous Carbon Matrix

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Chemical Research in Chinese Universities 2010年第3期26卷 348-351页

作者： YANG Kai-yu XU wei zhanG yu ZHENG wei-tao WANG Xin Center of Test Science State Key Laboratory of lnorganic Synthesis and Preparative Chemistry College of Chemistry Key Laboratory of Automobile Materials Ministry of Education College of Materials Science and Engineering Jilin University Changchun 130012 P R. China

We proposed a new way to synthesize a nanocomposite consisted of cementite Fe3C nanoparticles and amorphous carbon by radio frequency plasma-enhanced chemical vapor deposition. Transmission electron microscope images show the existence of nanometric dark grains（Fe3C） embedded in a light matrix（amorphous carbon） in the samples. X-ray photoelectron spectroscopy experiment exhibit that the chemical bonding state in the films corresponded to sp3/sp2 amorphous carbon, sp^3 C-N（287.3 eV） and C15 in Fe3C（283.5 eV）. With increasing deposition time, the ratio of amorphous carbon increased. The magnetic measurements show that the value of in-lane coercivity increased with increasing carbon matrix concentration（from about 6.56× 10^3 A/m for film without carbon structures to approximately 2.77× 10^4 and 5.81 × 10^4 AJm for nanocomposite films at room temperature and 10 K, respectively）. The values of saturation magnetization for the synthesized nanocomposites were lower than that of the bulk Fe3C （ 140 Am^2/kg）.

关键词： Fe3C nanoparticle Amorphous carbon Plasma enhancement chemical vapor deposition(PECVD) Magnetic property

Utilization-Aware Data Variable Allocation on NVM- Based SPM in Real-Time Embedded Systems

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Journal of Electronic Science and Technology 2021年第2期19卷 163-172页

作者： Jin-yu zhan Yi-Xin Li wei Jiang Jun-Huan Yang School of Information and Software Engineering University of Electronic Science and Technology of ChinaChengdu 610054 State Key Lab of Mathematical Engineering and Advanced Computing Wuxi 214000

With the development of the nonvolatile memory(NVM),using NVM in the design of the cache and scratchpad memory(SPM)has been *** paper presents a data variable allocation(DVA)algorithm based on the genetic algorithm for NVM-based SPM to prolong the *** lifetime can be formulated indirectly as the write counts on each SPM *** the differences between global variables and stack variables,our optimization model has three *** constraints of the central processing unit(CPU)utilization and size are used for all variables,while no-overlay constraint is only used for stack *** satisfy the constraints of the optimization model,we use the greedy strategy to generate the initial population which can determine whether data variables are allocated to SPM and distribute them evenly on SPM ***,we use the Mälardalen worst case executive time(WCET)benchmark to evaluate our *** experimental results show that the DVA algorithm can not only obtain close-to-optimal solutions,but also prolong the lifetime by 9.17% on average compared with SRAM-based SPM.

关键词： Data variables allocation genetic algorithm nonvolatile momory(NVM) scratchpad memory(SPM)

El Ni?o/Southern Oscillation during the 4.2 ka event recorded by growth rates of corals from the North South China Sea

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Acta Oceanologica Sinica 2020年第1期39卷 110-117页

作者： Shaohua Dang Kefu yu Shichen tao tao Han Huiling zhang wei Jiang Guangxi Laboratory on the Study of Coral Reefs in the South China Sea Guangxi UniversityNanning 530004China Coral Reef Research Center of China Guangxi UniversityNanning 530004China School of Marine Sciences Guangxi UniversityNanning 530004China South China Sea Institute of Oceanology Chinese Academy of SciencesGuangzhou 510301China College of Ocean Engineering Guangdong Ocean UniversityZhanjiang 524088China

The 4.2 ka event that occurred during the period from 4 500–3 900 a BP was characterized by cold and dry climates and resulted in the collapse of civilizations around the world. The cause of this climatic event, however, has been under debate. We collected four corals(Porites lutea) from Yongxing Island, Xisha Islands, South China Sea, dated them with the U-series method, and measured the annual coral growth rates using X-ray technology. The dating results showed that the coral growth ages were from 4 500–3 900 a BP, which coincide well with the period of the4.2 ka event. We then reconstructed annual sea surface temperature anomaly(SSTA) variations based on the coral growth rates. The growth rate-based SSTA results showed that the interdecadal SSTA from 4 500–3 900 a BP was lower than that during modern times(1961–2008 AD). A spectral analysis showed that the SSTA variations from4 500–3 900 a BP were under the influence of El Nino-Southern Oscillation(ENSO) activities. From 4 500–4 100 a BP, the climate exhibited La Nina-like conditions with weak ENSO intensity and relatively stable and lower SSTA amplitudes. From 4 100–3 900 a BP, the climate underwent a complicated period of ENSO variability and showed alternating El Nino-or La Nina-like conditions at interdecadal time scales and large SSTA amplitudes. We speculate that during the early and middle stages of the 4.2 ka event, the cold climate caused by weak ENSO activities largely weakened social productivity. Then, during the end stages of the 4.2 ka event, the repeated fluctuations in the ENSO intensity caused frequent extreme weather events, resulting in the collapse of civilizations worldwide. Thus, the new evidence obtained from our coral records suggests that the 4.2 ka event as well as the related collapse of civilizations were very likely driven by ENSO variability.

关键词： 4.2 ka event ENSO variability SSTA coral growth rate Xisha Islands

Characterization of Bacterial Community,Ammonia-Oxidizing Bacteria,and Nitrospira During the Operation of a Commercial-Scale Recirculating Aquaculture System for Culturing Pufferfish Takifugu rubripes

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Journal of Ocean University of China 2020年第6期19卷 1399-1408页

作者： MA yuexin yu Zichao DU Xin zhanG tao WANG Ning tao wei Key Laboratory of Environment Controlled Aquaculture Ministry of EducationDalian 116023China Liaoning Key Laboratory of Marine Animal Immunology and Disease Control Dalian Ocean UniversityDalian 116023China Dalian Tianzheng Industry Company Limited Dalian 116011China College of Environmental Science and Engineering Dalian Maritime UniversityDalian 116026China

We investigated the changes in communities of bacteria,ammonia-oxidizing bacteria,and Nitrospira during the operation of a pufferfish Takifugu rubripes recirculating aquaculture system by using high-throughput DNA *** in bacterial communities were observed at days 1-32,47-62 and 78-93 of biofilm development by using 16S rRNA gene *** relative abundance of Proteobacteria(Gammaproteobacteria)increased,while that of Bacteroidetes(Flavobacteria)*** proportions of Nitrosomonas and Nitrospina ranged from 0.02%to 0.30%and from 0.02%to 0.83%,*** monooxygenase gene pyrosequencing revealed that the top three operational taxonomic units were related to Nitrosomonas aestuarii(17.5%-61.1%),uncultured beta proteobacterium clone B67S-54(1.9%-45.2%),and uncultured bacterium clone AZPa8(3.6%-24.7%).Nitrite oxidoreductase gene pyrosequencing revealed that the relative abundance of the dominant strain Nitrospira *** 2.1 increased,but that of the abundant species Nitrospira marina *** results demonstrated that the communities of bacteria,ammonia-oxidizing bacteria,and Nitrospira were changing during the operation of the pufferfish recirculating aquaculture system.

关键词： biofilter bacterial community ammonia-oxidizing bacteria Nitrospira recirculating aquaculture system

Modeling the pressure drop of wet gas in horizontal pipe

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Chinese Journal of Chemical Engineering 2017年第7期25卷 829-837页

作者： Peining yu Yi Li Jing wei Ying Xu tao zhang Graduate School at Shenzhen Tsinghua UniversityShenzhen 518055China CFHI Tianjin C-E Electrical Automation Co.Ltd Tianjin 300457China School of Electrical Engineering and Automation Tianjin UniversityTianjin 300072China

A model for gas–liquid annular and stratified flow through a horizontal pipe is investigated, using the two-phase hydrokinetics theory. Taking into consideration the flow factors including the void fraction, the friction between the two phases and the entrainment in the gas core, the one-dimensional momentum equation for gas has been solved. The differential pressure of the wet gas between the two tapings in the straight pipe has been modeled in the pressure range of 0.1–0.8 MPa. In addition a more objective iteration approach to determine the local void fraction is proposed. Compared with the experimental data, more than 83% deviation of the test data distributed evenly within the band of ± 10%. Since the model is less dependent on the specific empirical apparatus and data,it forms the foundation for further establishing a flow measurement model of wet gas which will produce fewer biases in results when it is extrapolated.

关键词： Gas-liquid flow Pressure drop Hydrodynamics Model

VabHLH137 promotes proanthocyanidin and anthocyanin biosynthesis and enhances resistance to Colletotrichum gloeosporioides in grapevine

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Horticulture Research 2023年第2期10卷 106-117页

作者： Dan yu wei wei Zhongqi Fan Jianye Chen Yilin You weidong Huang Jicheng zhan Beijing Key Laboratory of Viticulture and Enology College of Food Science and Nutritional EngineeringChina Agricultural UniversityBeijing 100085China State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables College of HorticultureSouth China Agricultural UniversityGuangzhou510642China

Proanthocyanidins(PAs)and anthocyanins are involved in the response of plants to various environmental ***,the mechanism behind defense-induced PA biosynthetic regulation is still not completely elucidated,also in *** study performed a transcriptome sequencing analysis of grape berries infected with Colletotrichum gloeosporioides to highlight the induction of the VabHLH137 factor from the basic helix-loop-helix(bHLH)XII subfamily by the fungus,which appeared to be significantly co-expressedwith PA-related *** functional analysis of VabHLH137 overexpression and knockdownin transgenic grape calli showed that it positively regulated PA and anthocyanin ***,VabHLH137 overexpression in the grape calli significantly increased resistance to ***.A yeast one-hybrid and electrophoretic mobility shift assay revealed that VabHLH137 directly bound to the VaLAR2 promoter,enhancing its activity and interacting with VaMYBPAR,a transcriptional activator of PA ***,transient experiments showed that although the VabHLH137+VaMYBPAR complex activated VaLAR2 expression,it failed to further enhance VaLAR2 expression compared to VaMYBPAR *** findings indicated that VabHLH137 enhanced PA biosynthesis by activating of VaLAR2 expression,providing new insight into the transcriptional regulation of defense-induced PA biosynthesis in grapevine.

关键词： resistance alone biosynthesis

Characteristics of metal flow in cold extrusion under electric-hydraulic chattering

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Journal of Iron and Steel Research International 2017年第2期24卷 138-146页

作者： Zhi-heng Wang wei-tao zhan Xiao-xiao Hong Guan-jun Bao Qing-hua Yang Key Laboratory of E&M Zhejiang University of Technology Hangzhou 310032 Zhejiang China

An experimental setup for cold extrusion process with electric-hydraulic chattering was developed and its working principle was introduced. The finite element （FE） model for a kind of cup part （material： 20Cr） was built by using the software Deform-3D. FE simulation experiments with and without electric-hydraulic chattering were carried out to analyze the velocity fields and the metal grid flow lines. The extrusion ex- periments of the cup part were also performed under different conditions. The difference of metal flow lines with and without electric-hydraulic chattering was discussed via a scanning electron microscope （SEM） and the Keyence super-depth three-dimensional microscopic system. The results showed that with the electric-hydraulic chattering, the velocity of material flow increases, whereas deformation resistance decreases. Electric hydraulic chattering results in easy metal flow, small bending degree of metal flow lines, slender and dense metal grains, and thereby an improved quality of the deformed parts.

关键词： Cold extrusion Electric-hydraulic chattering Finite element analysis Material flow

Statistical properties of fatigue damage of Gaussian random loadings

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航空动力学报 2014年第3期29卷 596-603页

作者： CHENG Hong-wei tao Jun-yong CHEN Xun JIANG yu Science and Technology on Integrated Logistics Support Laboratory College of Mechatronic Engineering and AutomationNational University of Defense Technology

Firstly,the fatigue damages associated with the random loadings were always deemed as highcycle or very-high-cycle fatigue problems,and based on Chebyshev theorem,the number of rainflow cycles in a given time interval could be recognized as a constant by neglecting its ***,the randomness of fatigue damage induced by the distribution of rainflow cycles was *** to central limit theorem,the fatigue damage could be assumed to follow Gaussian distribution,and the statistical parameters:mean and variance,were derived from Dirlik's ***,the proposed method was used to a simulate Gaussian random loading and the measured random loading from an *** with observed results were carried out *** the first example,the relative errors of the proposed method are 2.29%,3.52%and 1.16%for the mean,standard deviation and variation coefficient of fatigue damage,*** the second example,these relative errors are 11.70%,173.32%and 18.20%,and the larger errors are attributable to non-stationary state of the measured loading to some extent.

关键词： random loading fatigue damage rainflow counting probability density function rainflow cycle range