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On the steady Prandtl boundary layer expansions

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Science China Mathematics 2023年第9期66卷 1993-2020页

作者： chen gao Liqun Zhang Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Hua Loo-Keng Key Laboratory of Mathematics Chinese Academy of SciencesBeijing 100190China

In this paper,we consider the zero-viscosity limit of the 2D steady Navier-Stokes equations in(0,L)×R+with no-slip boundary *** estimating the stream-function of the remainder,we justify the validity of the Prandtl boundary layer ***,we show the global stability under the concavity condition of the Prandtl profile for an arbitrarily large constant L when the Euler flow is shear.

关键词： Navier-Stokes equations Prandtl boundary layer zero-viscosity limit stream-function estimates of theremainder

The role of botanical gardens in scientific research, conservation, and citizen science

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Plant Diversity 2018年第4期40卷 181-188页

作者： gao chen Weibang Sun Kunming Botanical Garden Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 Yunnan China Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations Kunming 650204 China Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 Yunnan China

Plant diversity is currently being lost at an unprecedented rate, resulting in an associated decrease in ecosystem services. About a third of the world＇s vascular plant species face the threat of extinction due to a variety of devastating activities, including, over-harvesting and over exploitation, destructive agricul- tural and forestry practices, urbanization, environmental pollution, land-use changes, exotic invasive species, global climate change, and more. We therefore need to increase our efforts to develop integrative conservation approaches for plant species conservation. Botanical gardens devote their resources to the study and conservation of plants, as well as making the world＇s plant species diversity known to the public. These gardens also play a central role in meeting human needs and providing well-being. In this minireview, a framework for the integrated missions of botanical gardens, including scientific research, inJex situ conservation, plant resource utilization, and citizen science are cataloged. By reviewing the history of the development of Kunming Botanical Garden, we illustrate successful species conservation approaches （among others, projects involving Camellia, Rhododendron, Magnolia, Begonia, Alliurn, Ne- penthes, medicinal plants, ornamental plants, and Plant Species with Extreme Small Populations）, as well as citizen science, and scientific research at Kunming Botanical Garden over the past 80 years. We emphasize that Kunming Botanical Garden focuses largely on the ex situ conservation of plants from Southwest China, especially those endangered, endemic, and economically important plant species native to the Yunnan Plateau and the southern Hengduan Mountains. We also discuss the future chal- lenges and responsibilities of botanical gardens in a changing world, including： the negative effects of outbreeding and/or inbreeding depression; promoting awareness, study, and conservation of plant species diversity; accelerating global access t

关键词： Botanical gardens Citizen science Conservation biology Endangered plants Germplasm Horticulture

On the Largest Prime Factor of Shifted Primes

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Acta Mathematica Sinica,English Series 2017年第3期33卷 377-382页

作者： Feng Juan chen Yong gao chen School of Mathematical Sciences Soochow University School of Mathematical Sciences and Institute of Mathematics Nanjing Normal University

For any integer n ≥ 2, let P（n） be the largest prime factor of n. In this paper, we prove 1 This that the number of primes p 〈 x with P（p- 1） ≥ pC is more than （1 -c＋o（1））π（x） for 0 〈 c 〈 1/2 extends... 详细信息

关键词： Prime factor shifted prime

CONVERGENCE RATE OF A GENERALIZED ADDITIVE SCHWARZ ALGORITHM

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Journal of Computational Mathematics 2006年第5期24卷 635-646页

作者： Jin-ping Zeng gao-jie chen College of Mathematics and Econometrics Hunan University Changsha 410082 China

The convergence rate of a generalized additive Schwarz algorithm for solving boundary value problems of elliptic partial differential equations is studied. A quantitative analysis of the convergence rate is given for the model Dirichlet problem. It will be shown that a greater acceleration of the algorithm can be obtained by choosing the parameter suitably. Some numerical tests are also presented in this paper.

关键词： Schwarz additive algorithm Convergence rate Dirichlet problem.

Unscented Kalman filter for SINS alignment

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Journal of Systems Engineering and Electronics 2007年第2期18卷 327-333页

作者： Zhou Zhanxin gao Yanan chen Jiabin Dept. of Automatic Controls Beijing Inst. of Technology Beijing 100081 P. R. China

In order to improve the filter accuracy for the nonlinear error model of strapdown inertial navigation system （SINS） alignment, Unscented Kalman Filter （UKF） is presented for simulation with stationary base and moving base of SINS alignment. Simulation results show the superior performance of this approach when compared with classical suboptimal techniques such as extended Kalman filter in cases of large initial misalignment. The UKF has good performance in case of small initial misalignment.

关键词： Unscented Kalman filter Strapdown inertial navigation Alignment Extended Kalman filter.

Hyperthermia on skin immune system and its application in the treatment of human papillomavirus-infected skin diseases

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Frontiers of Medicine 2014年第1期8卷 1-5页

作者： Xinghua gao Hongduo chen Department of Dermatology the First Hospital of China Medical University Shenyang 110001 China

Hyperthermia is a condition characterized by increased body temperature as a consequence of failed thermoregulation. Hyperthermia occurs when a body produces or absorbs more heat than it dissipates. Hyperthermia also elicits various effects on the physiology of living cells. For instance, fever-range temperature （39 ℃ to 40 ℃） can modulate the activities of immune cells, including antigen-presenting cells, T cells, and natural killer cells. Heat shock temperature （41 ℃ to 43 ℃） can increase the immunogenicity of tumor cells. Cytotoxic temperature （〉 43℃ ℃） can create an antigen source to induce an anti-tumor immune response. The immunomodulatory effect of hyperthermia has promoted an interest in hyperthermia-aided immunotherapy, particularly against tumors. Hyperthermia has also been used to treat deep fungal, bacterial, and viral skin infections. We conducted a series of open or controlled trials to treat skin human papillomavirus infection by inducing local hyperthermia. More than half of the patients were significantly cured compared with those in the control trial. A series of challenging clinical cases, such as large lesions in pregnant patients or patients with diabetes mellitus, were also successfully and safely managed using the proposed method. However, further studies should be conducted to clarify the underlying mechanisms and promote the clinical applications of hyperthermia.

关键词： hyperthermia HPV immune response virus tumor

Five Consecutive Positive Odd Numbers None of Which Can Be Expressed as a Sum of Two Prime Powers Ⅱ

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Acta Mathematica Sinica,English Series 2008年第11期24卷 1883-1890页

作者： Yong gao chen Min TANG Department of Mathematics Nanjing Normal University Nanjing 210097 P. R. China Department of Mathematics Anhui Normal University Wuhu 241000 P. R. China

In this paper, we find two integers k0, m of 159 decimal digits such that if k ≡ k0 （mod m）, then none of five consecutive odd numbers k, k - 2, k - 4, k - 6 and k - 8 can be expressed in the form 2^n ± p^α, wher... 详细信息

关键词： Erdos problems covering systems odd numbers sums of prime powers

Data and knowledge-driven named entity recognition for cyber security

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Cybersecurity 2021年第1期4卷 123-135页

作者： chen gao Xuan Zhang Hui Liu School of Software Yunnan University650091 YunnanChina Key Laboratory of Software Engineering of Yunnan Province 650091 YunnanChina Engineering research center of cyberspace 650091 YunnanChina

Named Entity Recognition(NER)for cyber security aims to identify and classify cyber security terms from a large number of heterogeneous multisource cyber security *** the field of machine learning,deep neural networks automatically learn text features from a large number of datasets,but this data-driven method usually lacks the ability to deal with rare *** et *** a deep learning method for named entity recognition in the field of cyber security,and achieved good results,reaching an F1 value of 82.8%.But it is difficult to accurately identify rare entities and complex words in the *** cope with this challenge,this paper proposes a new model that combines data-driven deep learning methods with knowledge-driven dictionary methods to build dictionary features to assist in rare entity *** addition,based on the data-driven deep learning model,an attentionmechanism is adopted to enrich the local features of the text,better models the context,and improves the recognition effect of complex *** results show that our method is better than the baseline *** model is more effective in identifying cyber security *** Precision,Recall and F1 value reached 90.19%,86.60%and 88.36%respectively.

关键词： Cyber security Named entity recognition Attention mechanism Dictionary Deep learning

Global impact of RNA splicing on transcriptome remodeling in the heart

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第8期13卷 603-608页

作者： chen gao Yibin WANG Molecular Biology Institute University of California Los Angeles California 90095 USA

In the eukaryotic transcriptome, both the numbers of genes and different RNA species produced by each gene contribute to the overall complexity. These RNA species are generated by the utilization of different transcriptional initiation or termination sites, or more commonly, from different messenger RNA (mRNA) splicing events. Among the 30 000+ genes in human genome, it is estimated that more than 95% of them can generate more than one gene product via alternative RNA splicing. The protein products generated from different RNA splicing variants can have different intracellular localization, activity, or tissue-distribution. Therefore, alternative RNA splicing is an important molecular process that contributes to the overall complexity of the genome and the functional specificity and diversity among different cell types. In this review, we will discuss current efforts to unravel the full complexity of the cardiac transcriptome using a deep-sequencing approach, and highlight the potential of this technology to uncover the global impact of RNA splicing on the transcriptome during development and diseases of the heart.

关键词： Alternative RNA splicing Transcriptome,Gene regulation Heart RNA-seq