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Body-force modeling considering induced upstream effects for a transonic compressor with total temperature distortion

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Chinese Journal of Aeronautics 2024年第6期37卷 7-19页

作者： Jiahui QIU Chen YANG Wenqiang ZHANG Min ZHANG juan du Digital Twin Research Center Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China School of Engineering and Science University of Chinese Academy of SciencesBeijing 100190China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Chinese Academy of SciencesBeijing 100190China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

To numerically study the impact of total temperature distortion on a transonic compressor with reduced computational costs,a Body-Force Model(BFM)is ***,the interactions between the distorted flow and the compressor are analyzed using full-annulus Unsteady Reynolds-Averaged Navier-Stokes(URANS)results and the orbit *** is found that the induced swirl distortion and the mass flux nonuniformity are intensified in the compressor upstream flow field.A correction factor is thus added to the BFM to account for the effect of the induced swirl,which is crucial for the accurate representation of distortion transfer in the ***,steady simulations with large-amplitude 180circumferential total temperature distortion are performed using the developed *** is shown that the distorted compressor map simulated with the BFM matches well with URANS *** circumferential phase shift of total temperature and the generation of the additional total pressure distortion across the rotor are in line with the time-averaged URANS flow *** compressor upstream effects on the distorted inflow can also be exactly *** above-mentioned results demonstrate the BFM developed in this paper can effectively capture the distorted flow features inside the compressor,and significantly reduce the computational costs by five orders of magnitude compared with URANS.

关键词： Upstream effect Orbit method Induced swirl distortion Body force model Correction factor Time-averaged URANS

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Development of the electric automatic steering system for agricultural vehicles

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 209-214页

作者： Guangshun An Chong Yu juan du Xiang Yin Youliang Ni Chengqian Jin School of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255000ShandongChina Nanjing Research Institute for Agricultural Mechanization of Ministry of Agriculture and Rural Affairs Nanjing 210014China

Automatic guidance of agricultural vehicles requires automatic execution of operation commands received from the navigation controller by using electronically controlled mechanisms for wheel steering,speed changing and work *** steering contributes as a prerequisite technique in automatic and semi-automatic agricultural *** research aimed to develop an electric automatic steering system that was compact in its structure and integrated into original steering mechanism in a simply and convenient way for aftermarket modification.A brushless motor and reducer assembly was utilized to provide an adequate steering torque instead of manual maneuver.A rapid assembling approach was proposed by passing the steering shaft through the hollow output shaft.A digital proportional-integral-differential(PID)algorithm was implemented to calculate the rotation speeds and directions by comparing the desired angle and the actual angle,which was implemented in a printed circuit board with a microcontroller unit(MCU)and interface *** unmanned wheeled tractor was applied as test platform to integrate the newly developed electric automatic steering *** were conducted to evaluate its performance in terms of stability and *** autonomous navigation system guided the tractor along target paths in the field by sending steering commands to the electric automatic steering *** results show that the steering angle error was less than 0.81°when desired steering angle was less than 10°.The lateral error difference was no more than 4.76 cm when repeating following the same target path,which indicated that the electric automatic steering system responded accurately and robustly to steering commands.

关键词： automatic steering automatic navigation agricultural vehicles

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Modeling Near-Field Impulsive Waves Generated by Deformable Landslide Using the HBP Model Based on the SPH Method

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Journal of Ocean University of China 2024年第2期23卷 328-344页

作者： WANG Wei WEI Weicheng CHAI Bo XIA Hao WANG Yang du juan LIU Jizhixian School of Environmental Studies China University of GeosciencesWuhan 430078China Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science Wuhan 430078China Faculty of Engineering China University of GeosciencesWuhan 430074China Research Center for Geohazards Monitoring and Warning in Three Gorges Reservoir Wanzhou 404000China

Landslide-generated impulsive waves(LGWs)in reservoir areas can seriously threaten waterway safety as well as hu-man life and properties around the two side *** risk reduction and mitigation of such a hazard require the accurate prediction of near-field wave characteristics,such as wave amplitude and ***,near-field LGW involves complicated fluid-solid ***,the wave characteristics are closely related to various aspects,including the geometry and physical features of the slide,river,and body of ***,the empirical or analytical methods used for rough estimation cannot derive accurate results,especially for deformable landslides,due to their significant geometry changes during the sliding *** this study,the near-field waves generated by deformable landslides were simulated by smoothed particle hydrodynamics(SPH)based on multi-phase *** deformable landslides were generalized as a kind of viscous flow by adopting the Herschel-Bulkley-Papanastasiou(HBP)-based nonNewtonian rheology *** HBP model is capable of producing deformable landslide dynamics even though the high-speed sliding process is *** this study,an idealized experiment case originating from Lituya LGW and a practical case of Gongjiafang LGW were reproduced for verification and *** simulation results of both cases show satisfactory consistency with the experiment/investigation data in terms of landslide movement and near-field impulsive wave characteristics,thus indicating the applicability and accuracy of the proposed ***,the effects of the HBP model’s rheological parameters on the landslide dynamics and near-field wave characteristics are discussed,providing a parameter calibration method along with sug-gestions for further applications.

关键词： deformable landslide impulsive waves near-field SPH nonNewtonian fluids

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Research on the Spatio-Temporal Evolution and Driving Forces of Green Spaces in the Central Urban Area of Zunyi City

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Journal of Architectural Research and Development 2024年第4期8卷 8-16页

作者： juan du International College of Yunnan Agricultural University Kunming 650500Yunnan ProvinceChina

Green space,as a medium for carrying out urban functions and guiding urban development,is becoming a scarce resource along with the urbanization process and the intensification of environmental *** the face of the spatial mismatch between high demand and low supply,it is of great significance to clarify the evolution mechanism of green space to undertake national spatial planning,protect the natural strategic resources in the urban fringe area,and promote the sustainable development of the“three living spaces.”The study focuses on the Zunyi City Center,selecting the 20 years of rapid development following its establishment as a city as the study *** explores the dynamic evolution of green space and the main driving forces during different periods using remote-sensing image *** study shows that from 2003 to 2023,the total scale of green space has an obvious decreasing trend along with the expansion of the urban built-up area.A large amount of arable land is being converted to construction land,resulting in a sudden decrease in arable land *** the past 10 years,the comprehensive land use dynamics have ***,the spatial difference has gradually narrowed,indicating that the overall development intensity of Zunyi City’s central urban area has *** is a gradual spread of the trend to the hilly *** limiting effect of the mountainous natural environment on the city’s development has gradually diminished under the superposition of external factors,such as economic development,industrial technological upgrading,and policy orientation so the importance of the effective protection and rational utilization of urban green space has become more prominent.

关键词： Green space Spatio-temporal evolution Driving force Zunyi city center

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Comparison of the pathological characteristics of uninjured skin tissues of diabetic rodents and diabetic patients

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中华内分泌外科杂志（中英文） 2024年第3期18卷 339-345页

作者： du juan Liu Ying Zhu Anfeng Song Dongming Qu Shiguang Yuan Zhixin Emergency Critical and Translational Medicine LaboratoryJilin Province People’s HospitalChangchun 130021China Emergency Medicine Department of General Hospital of Northern Theater Command Laboratory of Rescue Center of Severe Wound and Trauma PLAShenyang 110016China Department of Pathology the Centre Hospital of ChangchunChangchun 130021China Department of Emergency Surgery Jilin Province People’s HospitalChangchun 130021China

Objective To study uninjured diabetic skin structure and compare the pathological characteristics of skin tissue from mouse and rat models of diabetes mellitus(DM)and humans with *** Establishing the DM C57BL/6J mice skin tissue models and db/db mice skin tissue models,as well as DM rat skin tissue *** tissues were collected from the animal models and DM *** biopsy specimens were stained with hematoxylin and eosin(HE)staining,Masson trichrome staining and periodic acid-Schiff(PAS)***(1)Skin from mice with streptozotocin(STZ)-induced DM was thinner and had less hair than skin from control *** epidermis had abnormal keratinization and dermal collagen and elastin fibers were dense and significantly atrophied.(2)Compared with the control group,skin tissue from db/db mice was thinner and had less *** was no aberrant keratinization in the epidermis,and dermal collagen and elastin fibres were loose.(3)Skin tissue from rats with STZ-induced DM was significantly thinner than control *** epidermis had mildly abnormal keratinization,and the dermis layer was atrophied and partly *** focal lipofuscin was deposited.(4)Whole skin tissue from patients with diabetes was significantly thinner than skin from subjects without *** epidermis had mild hyper keratinization,and the dermal elastin fibers were atrophied,loose,irregular,and showed focal mucoid *** Uninjured DM skin tissues were thinner and more irregular than normal *** changes in rat DM skin were most like those seen in the skin of patients with DM.

关键词： Diabetes mellitus Skin Human Mouse Rat

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Effects of Al_(2)O_(3)-SiO_(2) Raw Material Types on Properties of Anorthite Based Insulation Refractories

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China's Refractories 2024年第1期33卷 23-27页

作者： du juan GUO Huishi YANG Jialin LI Wenfeng GUI Yanghai ZHAO Zhiqiang LIU Yingfan School of Materials Science and Engineering Henan University of TechnologyZhengzhou 450001China School of Materials and Chemical Engineering Zhengzhou University of Light IndustryZhengzhou 450051China

To optimize their Al_(2)O_(3)-SiO_(2) raw materials,anorthite based insulation refractories were prepared by the in-situ sintering process combined with the foaming method after sintering at 1350℃for 3 h,using green and pollution-free kaolin,kyanite,andalusite and sillimanite as Al_(2)O_(3)-SiO_(2) raw materials,respectively,and industrial CaCO_(3) as the CaO *** of Al_(2)O_(3)-SiO_(2) raw material types on the physical properties,phase composition and microstructure were *** results are as *** samples prepared by different Al_(2)O_(3)-SiO_(2) raw materials have hexagonal flake anorthite and a small amount of mullite and *** bulk density and thermal conductivity decrease in the order of using kaolin,andalusite,kyanite and sillimanite as the Al_(2)O_(3)-SiO_(2) raw material,but their apparent porosity ***,in the sample with kaolin,the bonding between anorthite crystals on the pore walls is closer than that of the other samples,which is conducive to increasing the cold crushing *** bonding between anorthite crystals on pore walls gradually decreases in the order of using kyanite,andalusite and sillimanite as the Al_(2)O_(3)-SiO_(2) raw material,thus their cold crushing strength decreases *** comprehensive consideration,the properties of the sample from kyanite are the *** apparent porosity,thermal conductivity and cold crushing strength are 84.6%,0.141 W·m^(-1)·K^(-1) and 1.89 MPa,respectively.

关键词： anorthite based insulation refractories Al_(2)O_(3)-SiO_(2)raw materials crushing strength thermal conductivity microstructure

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Left bundle branch area pacing combined with implantable cardioverter-defibrillator treatment for heart failure after myocardial infarction

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Journal of Geriatric Cardiology 2024年第5期21卷 577-582页

作者： Bing-Chen GUO Jian XU Yan-Zong LIU Guo-Qing du Bo YU Shu-Feng LI Wen-juan du Department of Cardiology the 2nd Affiliated Hospital of Harbin Medical UniversityHarbinChina The Key Laboratory of Myocardial Ischemia Chinese Ministry of EducationHarbinChina Department of Ultrasonography Guangdong Provincial People's HospitalGuangzhouGuangdongChina

Left bundle branch area pacing(LBBAP)has emerged as a new physiological pacing *** studies have confirmed the feasibility and efficacy of LBBAP for cardiac resynchronization therapy(CRT)in heart failure(HF)patients with left bundle branch block(LBBB)and a narrower QRS duration(QRSd)to have a higher percentage of super responders,and lower pacing thresholds than biventricular pacing(BiVP).

关键词： pacing branch bundle

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巴西排日运动与1934年《百分之二限额法案》的颁布

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史学集刊 2024年第2期 96-106页

作者：杜娟中国社会科学院世界历史研究所北京100101

1931年日本悍然发动了“九一八”事变,其帝国主义侵略行径遭到巴西的抵制,同时也引发了巴西国内针对日侨群体的猜疑和排斥。在巴西民族主义的语境下,“黄祸论”“不易被同化论”等种族主义论调频繁出现,针对日本移民的扩张阴谋论流行开... 详细信息

1931年日本悍然发动了“九一八”事变,其帝国主义侵略行径遭到巴西的抵制,同时也引发了巴西国内针对日侨群体的猜疑和排斥。在巴西民族主义的语境下,“黄祸论”“不易被同化论”等种族主义论调频繁出现,针对日本移民的扩张阴谋论流行开来。1933年年底,限制外来移民的宪法修正案提案引发了巴西国内排日派和挺日派的激烈争论。1934年5月24日,巴西国会通过了《百分之二限额法案》,并将其列入《1934年宪法》,这是近代以来巴西第一次对所有外来移民采取限制措施,也是首次将限制移民入境写进宪法,确立了国籍来源的移民配额制度。作为20世纪30年代初增长最为迅猛的外来移民群体,日本移民受该法案的冲击最大。对此,日本政府积极打经贸亲善牌,开启了“棉花换移民”外交,以缓和改善日巴关系;而日本媒体和巴西日侨对该法案的颁布表示强烈不满,他们用实际行动反击排日言论。该法案对日本在巴西的投资置地和移民活动都产生了消极影响。

关键词：巴西日本移民排日《百分之二限额法案》民族主义

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生成式人工智能的扩展风险与社会规制——基于ChatGPT社会效应的探讨

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东北师大学报（哲学社会科学版） 2024年第2期 127-133页

作者：杜娟华东政法大学法律学院上海200042 黑龙江省社会科学信息中心黑龙江哈尔滨150001

生成式人工智能作为人工智能领域的新技术范式,高频迭代进化并拓展出功能强大的大语言模型ChatGPT,这无疑突显了人工智能技术的卓越性,但由此也引发了关于人工智能经济奇点、政治奇点、社会奇点等社会治理风险的深度思考。因此,如何在... 详细信息

生成式人工智能作为人工智能领域的新技术范式,高频迭代进化并拓展出功能强大的大语言模型ChatGPT,这无疑突显了人工智能技术的卓越性,但由此也引发了关于人工智能经济奇点、政治奇点、社会奇点等社会治理风险的深度思考。因此,如何在人工智能技术逻辑中深入理解人工智能时代风险的成因、特质和趋势,并为应对这些风险提供坚实的理论基础、治理思维和实践策略,已成为当今社会迫切需要解决的问题。在我们看来,面对如ChatGPT等生成式人工智能扩展的风险,我们只有深化数据安全的意识,形成认知风险边界的能力,才能真正从社会发展角度规制技术产生的社会风险。

关键词：生成式人工智能风险扩展技术逻辑数据安全奇点风险

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Switching On/Off of Guide RNA by Photoinduced Strand Displacement for Functional Control of CRISPR/Cas9

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CCS Chemistry 2024年第5期6卷 1338-1351页

作者： Yang Wang Chao-Qun Wu Qiu-Long Zhang Ming Shao Yan Liu Liang-Liang Wang Zun-Yun Wang juan du Liang Xu Central Laboratory Department of the Second Affiliated Hospital School of MedicineThe Chinese University of Hong KongShenzhen&Longgang District People’s Hospital of ShenzhenShenzhen 518172 Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging National-Regional Key Technology Engineering Laboratory for Medical UltrasoundSchool of Biomedical EngineeringShenzhen University Medical SchoolShenzhen 518060 MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistrySun Yat-sen UniversityGuangzhou 510275 School of Pharmacy and Medical Technology Putian UniversityPutian 351100

Functional control of CRISPR/Cas9 is essential for precise gene *** engineering of guide RNA(gRNA)provides diverse approaches for conditional control of CRISPR/Cas9 function with a variety of chemical reactive ***,previous investigations into chemically engineering gRNA only unidirectionally regulated the CRISPR/Cas9 function via stimuli-induced caging/decaging ***,we propose a combinatory strategy to engineer the dynamics of gRNA in which photocontrolled strand-displacement reactions coupled with sequence designs of gRNA can achieve lightinduced switching-on/off control of CRISPR/Cas9 *** analysis and cellular gene regulation indicate this approach is capable of both activating and deactivating CRISPR/Cas9 activities using light ***,photocontrolled multiplex modulations of gene expression for opposite regulatory effects have also been achieved simultaneously under the same cellular *** work establishes an essential principle for construction of stimuli-induced switching-on/off modulations of gRNA that can greatly enrich the versatility of conditional control for a variety of CRISPR/Cas9-based applications.

关键词： modified oligonucleotides gene manipulation optical control CRISPR/Cas9 strand displacement

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