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Using Image Processing Technology and General Fluid Mechanics Principles to Model Smoke Diffusion in Forest Fires

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Fluid Dynamics & Materials Processing 2021年第6期17卷 1213-1222页

作者： liying Zhu ang Wang Fang Jin Institute of Civil Engineering Huanghe S&T UniversityZhengzhou450063China

In the present study,the laws of smoke diffusion during forest fires are determined using the general principles of fluid mechanics and dedicated data obtained experimentally using an“ad hoc”imaging *** images mimicking smoke in a real scenario are used to extract some“statistics”.These in turn are used to obtain the“divergence”of the flow(this fluid-dynamic parameter describing the amount of air that converges to a certain place from the surroundings or vice versa).The results show that the divergence of the smoke depends on the outside airflow and finally tends to zero as time *** remarkably,compared with clouds and fog,smoke has a unique dynamic time-evolution *** present study demonstrates that as long as image processing technology and intelligent monitoring technology are used to monitor the gas flow in a forest,the occurrence of forest fires can be quickly diagnosed.

关键词： Fluid mechanics image processing smoke diffusion forest fire

Fast frequency-domain equalization for single-carrier V-BlAST systems over multipath channel

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Science in China(Series F) 2009年第1期52卷 115-125页

作者： FENG ang YIN QinYe FAN JianCun School of Electronics and Information Engineering Xi'an Jiaotong University Xi'an 710049 China

A low complex minimum mean-square error frequency-domain decision feedback （MMSE-FDDF） equalization algorithm is proposed in this paper for the single-carrier V-BlAST systems. Exploiting the factor that the discrete Fourier transform （DFT） is unitary, the proposed receiver can equalize the signals by the MMSE detecting to the spectrums in the frequency domain instead of the waveforms in the time domain. In order to obtain the right decisions, the detector must be able to equalize the overall spectrum with regard to each layer. This work can be performed very efficiently since the system matrix has been designed as a special block-circulant-block matrix. Similar to other V-BlAST-like systems, the detecting order has strong impact on the performance of MMSE-FDDF. Therefore, we further give a fast optimally sorting scheme for the MMSE-FDDF architecture. By using the newly constructed matrix, the coefficients computation and the sorting can be combined into one process, and then we employ the modified Gram-Schmidt （MGS） to simplify the process. The simulation results and the computational complexity analysis show that the proposed MMSE-FDDF has better tradeoff between the performance and the complexity than the existing algorithms. In addition, MMSE-FDDF can avoid the performance floor caused by the overlap-and-save technique in the severe dispersive channel.

关键词： single-carrier orthogonal frequency division multiplexing frequency domain equalization V-BlAST ordering Cholesky decomposition

Strange star candidates revised within a quark model with chiral mass scaling

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Research in Astronomy and Astrophysics 2011年第4期11卷 482-490页

作者： ang li Guang-Xiong Peng Ju-Fu lu Department of Physics and Institute of Theoretical Physics and Astrophysics Xiamen University Xiamen 361005 China Department of Physics Graduate University Chinese Academy of Sciences Beijing 100049 China

We calculate the properties of static strange stars using a quark model with chiral mass scaling. The results are characterized by a large maximum mass （-1.6 M⊙） and radius （-10km）. Together with a broad collection of modern neutron star models, we discuss some recent astrophysical observational data that could shed new light on the possible presence of strange quark matter in compact stars. We conclude that none of the present astrophysical observations can prove or confute the existence of strange stars.

关键词： dense matter -- elementary particles -- equation of state -- stars: inte-riors

A Recommendation Method for highly Sparse Dataset Based on Teaching Recommendation Factorization Machines

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Computers, Materials & Continua 2020年第9期64卷 1959-1975页

作者： Dunhong Yao Shijun li ang li Yu Chen School of Computer Science and Engineering Huaihua UniversityHuaihua418000China Key laboratory of Wuling-Mountain health Big Data Intelligent Processing and Application in hunan Province Universities Huaihua418000China Key laboratory of Intelligent Control Technology for Wuling-Mountain Ecological Agriculture in hunan Province Huaihua418000China School of Computer Wuhan UniversityWuhan430072China Department of Electrical and Computer Engineering Duke UniversityDurhamNC 27708USA School of Computer Science and Engineering Yulin Normal UniversityYulin537000China

There is no reasonable scientific basis for selecting the excellent teachers of the school’s *** solve the practical problem,we firstly give a series of normalization models for defining the key attributes of teachers’professional foundation,course difficulty coefficient,and comprehensive evaluation of ***,we define a partial weight function to calculate the key attributes,and obtain the partial recommendation ***,we construct a highly sparse Teaching Recommendation Factorization Machines(TRFMs)model,which takes the 5-tuples relation including teacher,course,teachers’professional foundation,course difficulty,teaching evaluation as the feature vector,and take partial recommendation value as the recommendation ***,we design a novel Top-N excellent teacher recommendation algorithm based on TRFMs by course classification on the highly sparse *** results show that the proposed TRFMs and recommendation algorithm can accurately realize the recommendation of excellent teachers on a highly sparse historical teaching *** recommendation accuracy is superior to that of the three-dimensional tensor decomposition model algorithm which also solves sparse *** proposed method can be used as a new recommendation method applied to the teaching arrangements in all kinds of schools,which can effectively improve the teaching quality.

关键词： highly sparse dataset normalized models teaching recommendation factorization machines excellent teacher recommendation

Vision navigation for aircrafts based on 3D reconstruction from real-time image sequences

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Science China(Technological Sciences) 2015年第7期58卷 1196-1208页

作者： ZhU ZunShang SU ang lIU haiBo Shang Yang YU QiFeng College of Aerospace Science and Engineering National University of Defense Technology hunan Key laboratory of Videometrics and Vision Navigation

In this paper,we propose a novel vision navigation method based on three-dimensional(3D)reconstruction from real-time image *** adapts 3D reconstruction and terrain matching to establish the correspondence between image points and3D space points and the terrain reference(by using a digital elevation map(DEM)).An adaptive weighted orthogonal iterative pose estimation method is employed to calculate the position and attitude angle of the *** and real experiments show that the proposed method is capable of providing accurate navigation parameters for a long-endurance flight without using a global positioning system or an inertial navigation system(INS).Moreover,it can be combined with an INS to achieve an improved navigation result.

关键词： vision navigation 3D reconstruction terrain matching pose estimation

Estimates for the ruin probability of a time-dependent renewal risk model with dependent by-claims

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Applied Mathematics(A Journal of Chinese Universities) 2015年第3期30卷 347-360页

作者： FU Ke-ang QIU Yu-yang Wang An-ding School of Statistics and Mathematics Zhejiang Gongshang University

Consider a continuous-time renewal risk model, in which every main claim induces a delayed by-claim. Assume that the main claim sizes and the inter-arrival times form a sequence of identically distributed random pairs, with each pair obeying a dependence structure, and so do the by-claim sizes and the delay times. Supposing that the main claim sizes with by-claim sizes form a sequence of dependent random variables with dominatedly varying tails, asymptotic estimates for the ruin probability of the surplus process are investigated, by establishing a weakly asymptotic formula, as the initial surplus tends to infinity.

关键词： by-claim dominatedly varying tail extended upper negative dependence quasi-asymptotic independence ruin probability time-depende

Recent advances on the total synthesis of alkaloids in China's mainland

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National Science Review 2017年第3期4卷 397-425页

作者： Yong li Jian li hanfeng Ding ang li State Key laboratory of Bioorganic and Natural Products Chemistry Collaborative Innovation Center of Chemistry for Life SciencesShanghai Institute of Organic ChemistryChinese Academy of Sciences Zhejiang Key laboratory of Alternative Technologies for Fine Chemicals Process Shaoxing University Department of Chemistry Zhejiang University

Alkaloids are a large family of natural products that mostly contain basic nitrogen atoms. Because of their intriguing structures and important functions, they have long been popular targets for synthetic organic chemists. China’s chemists have made significant progress in the area of alkaloid synthesis over past decades. In this article, selected total syntheses of alkaloids from research groups in China’s mainland during the period 2011–16 are highlighted.

关键词： total synthesis natural products alkaloids

higher Body Temperatures and Earlier Parturition in Response to hypoxia Experienced by Pregnant lizards

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Asian herpetological Research 2021年第2期12卷 228-233页

作者： Zhongwen JIang liang Ma Shi'ang Tao Xingzhi han Key laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Princeton School of Public arui International Affairs Princeton UniversityPrincetonNew Jersey 08544USA College of Chemistry and life Sciences Zhejiang Normal UniversityJinhua 321004ZhejiangChina College of Wildlife and Protected Area Northeast Forestry UniversityHarbin 150040HeilongjiangChina

Many species are shifting towards higher altitudes in response to global wa rming, but how these upslope-shifting species will respond to hypoxic environments at high altitudes remains unclear. hypoxia can be especially challenging for viviparous reproduction because of the limitation of oxygen supply to the female and her developing embryos. To investigate the effect of hypoxia on viviparous females and their offspring we acclimated pregnant females of a high-altitude dwelling vivipa rous liza rd(Phr ynocephalus vlangalii) to local oxygen and hypoxia conditions, respectively. We then recorded maternal body temperatures, postpartum body condition, as well as offspring morphology and locomotor performance. We found that pregnant females had higher body temperatures and advanced their parturition under hypoxic acclimation. however, maternal body condition, offspring morphology and locomotor performance were unaffected by the hypoxic conditions during gestation. Our study suggests that upslope-shifting viviparous lizards respond to hypoxic environments by plastically adjusting their body tempera tures to reduce parturition time, without short-term costs to offspring traits.

关键词： climate change hypoxia offspring pregnant female reproduction viviparous lizard

A scoping review on traditional medicine for bruxism

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Journal of Traditional Chinese Medical Sciences 2023年第2期10卷 141-149页

作者： lin ang Eunhye Song Myeong Soo lee Yee ang KM Science Research Division Korea Institute of Oriental MedicineDaejeon34054Republic of Korea Global Cooperation Center Korea Institute of Oriental MedicineDaejeon34054Republic of Korea Conservative Department Faculty of DentistryMAHSA UniversitySelangor42610Malaysia

Objective:To investigate the current evidence on traditional medicine in managing bruxism and its clinical ***:A search was conducted in nine databases to identify potential eligible articles published from the date of inception until August 3,*** clinical studies that used traditional medicine of any type in treating bruxism were eligible for *** authors performed data extraction and quality as-sessments *** data were tabulated and discussed ***:A total of 16 clinical studies were included in this scoping *** the 16 studies,three studies were randomized controlled trials,one was a caseecontrol study,10 were case series,and two were case *** review identified studies of interventions based on herbal medicine and acupuncture-related *** studies reported positive results,but the overall quality of the included studies was typically fair to ***:This study is the first scoping review on traditional medicine for bruxism despite the limited *** research on traditional medicine in bruxism management should be conducted for better clarification and application in daily practice.

关键词： Acupuncture-related therapies Alternative therapy herbal medicine Parafunctional habit Teeth grinding