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Parametric Geometric Model and Hydrodynamic Shape Optimization of A Flying-Wing Structure Underwater Glider

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China Ocean Engineering 2017年第6期31卷 709-715页

作者： wang Zhen-yu YU Jian-cheng ZHANG Ai-qun wang ya-xing ZHAO Wen-tao State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

Combining high precision numerical analysis methods with optimization algorithms to make a systematic exploration of a design space has become an important topic in the modern design methods. During the design process of an underwater glider＇s flying-wing structure, a surrogate model is introduced to decrease the computation time for a high precision analysis. By these means, the contradiction between precision and efficiency is solved effectively. Based on the parametric geometry modeling, mesh generation and computational fluid dynamics analysis, a surrogate model is constructed by adopting the design of experiment （DOE） theory to solve the multi-objects design optimization problem of the underwater glider. The procedure of a surrogate model construction is presented, and the Gaussian kernel function is specifically discussed. The Particle Swarm Optimization （PSO） algorithm is applied to hydrodynamic design optimization. The hydrodynamic performance of the optimized flying-wing structure underwater glider increases by 9.1%.

关键词： surrogate model underwater glider design optimization blended-wing-body

Temperate northern hemisphere dominates the global soil CH_(4) sink

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Journal of Mountain Science 2022年第11期19卷 3051-3062页

作者： XU Xin WEI Da QI ya-hui wang Xiao-dan Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China

Methane(CH_(4)) is the second largest longlived greenhouse gas after the CO_(2), which contributes 20% of global warming forcing. Global aerated soils remove CH_(4) from the troposphere, but the quantification of its magnitude and spatial variability is still of a large uncertainty. This study collected 1240records of the CH_(4) uptake by soils across the *** estimates update the global soil CH_(4) sink to 31.9+/-0.16 Tg CH_(4) a^(-1), 42% higher than the previous inventory-based estimation, with 56% from temperate regions. Also, our dataset revealed that the global drylands dominated the soil CH_(4) sink, which is different from traditional forest-dominated *** the past four decades, the soil porosity affected by soil moisture controls the variation in the uptake in the tropics, while warming temperatures benefit methanotrophs in temperate and boreal soils,especially the drylands, where the soil porosity is not limiting. Our simulations indicate that the CH_(4) uptake will increase by 11%–31% by the end of the 21st century, much lower than the previous *** study substantially constrains the global soil CH_(4) sink estimates and reveals the warming temperate northern hemisphere is a dominant CH_(4) uptake region in the past and future, while the uptake decreases in tropical soils under increasing precipitation.

关键词： Climate change Methane uptake Northern hemisphere Observations Simulations

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针对混合输入的源代码分类技术

通信技术 2024年第7期57卷 725-730页

作者：刘赟张位郑周荣王梦国防科技工业网络安全创新中心四川成都610041 中电科网络空间安全重点实验室四川成都610041 中国电子科技集团公司第三十研究所四川成都610041

源代码分类是源代码共享、数据泄露防护和数据安全治理等领域实现代码类资产安全保护的关键基础之一。统计分析、机器学习和深度学习等方法被广泛应用于源代码分类技术,提高了源代码识别分类的准确性。但是,这些技术通常要求输入完整的... 详细信息

源代码分类是源代码共享、数据泄露防护和数据安全治理等领域实现代码类资产安全保护的关键基础之一。统计分析、机器学习和深度学习等方法被广泛应用于源代码分类技术,提高了源代码识别分类的准确性。但是,这些技术通常要求输入完整的源代码文件或纯代码片段,当输入数据中混入json、xml、字符乱码或中英文语句等非代码文件时,源代码识别分类的准确率明显下降。为此,提出了一种基于自然语言处理的代码特征提取方法,同时改进了模型输出,在输出结果中加入各类代码和非代码占比信息。该方法通过对逻辑回归模型调优,在代码、非代码或二者混合输入的情况下,对20类编程语言和非代码语言分类的准确率达到98.8%,解决了混合输入情况下代码分类准确率低的问题。

关键词：源代码分类自然语言处理特征提取逻辑回归

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环γ-聚谷氨酸的制备及美白活性研究

食品与药品 2024年第1期26卷 49-56页

作者：王梦灿朱希强林剑山东丰金生物医药有限公司山东烟台264100 烟台大学生命科学学院山东烟台264005

目的制备环γ-聚谷氨酸,研究其美白活性。方法以谷氨酸(Fmoc-Glu-OTBU)为原料,制备四元、八元和十元的环γ-聚谷氨酸(cyclo-γ-PGA),通过体外和细胞内实验,研究3种不同相对分子质量(M_(r))的cyclo-γ-PGA的酪氨酸酶抑制活性。结果测... 详细信息

目的制备环γ-聚谷氨酸,研究其美白活性。方法以谷氨酸(Fmoc-Glu-OTBU)为原料,制备四元、八元和十元的环γ-聚谷氨酸(cyclo-γ-PGA),通过体外和细胞内实验,研究3种不同相对分子质量(M_(r))的cyclo-γ-PGA的酪氨酸酶抑制活性。结果测得3种产物四元cyclo-γ-PGA、八元cyclo-γ-PGA和十元cyclo-γ-PGA纯度分别为98.31%,95.29%,95.67%,M_(r)分别为516.39,1032.83,1291.28。以γ-PGA为对照品,3种不同M_(r)的cyclo-γ-PGA均具有不同程度的酪氨酸酶抑制活性,其中十元cyclo-γ-PGA酪氨酸酶活性在体外和细胞内均最强。结论 cyclo-γ-PGA具有美白活性,美白活性随着M_(r)的增大而增加,且在细胞内的特性表现更优异;cyclo-γ-PGA的美白活性要高于γ-PGA,为后续cyclo-γ-PGA用于皮肤美白和化妆品领域中提供理论基础。

关键词：环γ-聚谷氨酸美白活性酪氨酸酶抑制小鼠黑色素瘤细胞

Ketogenic diet:new avenues to overcome colorectal cancer

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Signal Transduction and Targeted Therapy 2022年第9期7卷 3145-3146页

作者： Yuancai Xiang meng wang Hongming Miao Department of Biochemisty and Molecular Biology Third Military Medical University(Army Medical University)Chongqing 4008 China Department of Biochemistry and Molecular Biology Southwest Medical UniversityLuzhou 646000China

In a recent article published in Nature,Dmitrieva-Posocco et al.1showed that ketogenic diets(KD)exert strong abilities to prevent and treat colorectal cancer(CRC)via the ketone bodyβ-hydroxybutyrate(BHB)-mediated hyd... 详细信息

关键词： colorectal al. cancer

New insights on linear cryptanalysis

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Science China(Information Sciences) 2020年第1期63卷 104-114页

作者： Zhiqiang LIU Shuai HAN Qingju wang Wei LI ya LIU Dawu GU Department of Computer Science and Engineering Shanghai Jiao Tong University State Key Laboratory of Cryptology School of Computer Science and Technology Donghua University Department of Computer Science and Engineering University of Shanghai for Science and Technology

Linear cryptanalysis is one of the most important cryptanalytic tools against block ciphers,thus modern block ciphers are always deliberately devised to avoid good long linear characteristics so as to resist linear cryptanalysis and its extensions. Differential-linear cryptanalysis, a powerful extension of linear cryptanalysis, has drawn much attention due to its applicability even in certain case that there is no good long linear characteristic of block ciphers. To further refine differential-linear cryptanalysis, we investigate the correlation distribution of differential-linear hull over random permutation and derive a concrete and concise correlation distribution accordingly. Theoretically, this could make differential-linear cryptanalysis more reasonable and precise. Moreover, the newly-proposed correlation distribution could lead to an interesting potential for improving the effectiveness of differential-linear cryptanalysis.

关键词： block cipher linear cryptanalysis differential-linear cryptanalysis correlation distribution key-dependent differential-linear hull

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CD38基因敲除的淋巴瘤细胞株构建

现代生物医学进展 2024年第10期24卷 1807-1812页

作者：刘秀盈于梦圆冯娅茹宋志茹刘静静王建勋北京中医药大学生命科学学院北京102488 深圳细胞谷生物医药有限公司广东深圳518118 深圳北京中医药大学研究院广东深圳518118

目的:构建Luc^(+)CD38^(-)的Raji细胞株,并进行功能的初步验证,为后期探索淋巴瘤细胞CD38位点免疫逃逸现象奠定基础。方法:通过CRISPR-cas9技术和Piggy Bac(PB)转座子系统,对Luc^(+)Raji细胞的CD38基因位点进行敲除,构建Luc^(+)CD38^(-)... 详细信息

目的:构建Luc^(+)CD38^(-)的Raji细胞株,并进行功能的初步验证,为后期探索淋巴瘤细胞CD38位点免疫逃逸现象奠定基础。方法:通过CRISPR-cas9技术和Piggy Bac(PB)转座子系统,对Luc^(+)Raji细胞的CD38基因位点进行敲除,构建Luc^(+)CD38^(-)Raji细胞株,使用流式细胞术检测与Luc^(+)CD38^(-)Raji细胞株以1:1的比例共孵育CD19 CAR-T和CD38 CAR-T以及未转导的原始T细胞表面活化因子CD69的表达水平,荧光素酶检测法检测上述几组效应细胞对Luc^(+)CD38^(-)Raji细胞株的杀伤效率。结果:成功构建Luc^(+)CD38^(-)Raji细胞,激活实验结果显示,CD19 CAR-T与CD38 CAR-T均可以被Luc^(+)Raji细胞激活。而Luc^(+)CD38^(-)Raji19号单克隆细胞由于缺失CD38的表达,仅能够激活CD19 CAR-T。杀伤实验结果显示,两种CAR-T细胞均能够对Luc^(+)Raji细胞进行杀伤,而CD38 CAR-T对Luc^(+)CD38^(-)Raji19号单克隆细胞的杀伤效率与原始的T细胞相似。结论:成功构建了Luc^(+)CD38^(-)Raji细胞株,为后期探索淋巴瘤CD38位点免疫逃逸现象奠定基础。

关键词：淋巴瘤 CD38 Raji CAR-T CRISPR-cas9 PB转座子

Anisotropy of two-dimensional ReS_(2)and advances in its device application

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Rare Metals 2021年第12期40卷 3357-3374页

作者： ya-Di Cao Ying-Hui Sun Su-Fei Shi Rong-Ming wang Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface ScienceSchool of Mathematics and PhysicsUniversity of Science and Technology BeijingBeijing100083China Department of Chemical and Biological Engineering Rensselaer Polytechnic InstituteTroyNY 12180USA Department of Electrical Computer and Systems EngineeringRensselaer Polytechnic InstituteTroyNY 12180USA

Two-dimensional(2D)transition metal dichalcogenides(TMDCs)have attracted growing interest regarding their potential applications in next-generation electronic and optoelectronic *** to their atomic thickness and tunable bandgap,they exhibit unique mechanical,electrical,and optical *** a specific member of the TMDC family,rhenium disulfide(ReS_(2))has stimulated intensive interest due to its anisotropic crystal structure,weak inter-layer coupling,and anisotropic electrical and optical *** this review,we summarize the distinct crystal structure and intrinsic anisotropic properties of ReS_(2),followed by an introduction to its synthesis *** current applications of ReS_(2)and its heterojunctions are presented based on its anisotropic *** review not only provides a timely summary of the current applications of ReS_(2)and its heterojunctions,but also inspires new approaches to develop other innovative devices based on 2D materials with a low lattice symmetry.

关键词： Transition metal dichalcogenides(TMDCs) Rhenium disulfide Anisotropic property Heterojunction Functional device

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工程监理风险事件关联性分析研究

工程与建设 2024年第2期38卷 450-452,475页

作者：尹春丽秦濛王茜赵猛张欣高磊江苏兴力工程管理有限公司江苏南京211102 河海大学土木与交通学院江苏南京210024

在我国工程监理事业不断发展的背景下,由于工程的复杂性和监理的专业化,使得工程监理人员所面临的风险呈现出多样性的特点,工程监理风险事件时有发生。本文以某电力工程监理企业为研究对象,通过对该企业员工在工程中所面临的监理风险进... 详细信息

在我国工程监理事业不断发展的背景下,由于工程的复杂性和监理的专业化,使得工程监理人员所面临的风险呈现出多样性的特点,工程监理风险事件时有发生。本文以某电力工程监理企业为研究对象,通过对该企业员工在工程中所面临的监理风险进行关联性分析,从工程监理各个关键环节入手,以人为主要因素构建工程监理风险预判体系,推进“事后监督”向“事前预防”和“过程监督”转变,为电力工程建设提供保障。

关键词：工程监理风险评估关联性分析事前预防