检索结果-南通市图书馆

Spatial and Temporal Stress Variations before and after the 2008 Wenchuan M_(w)7.9 Earthquake and its Implications:A Study based on Borehole Stress Data

在线全文

学校读者我要写书评

暂无评论

Acta geologica Sinica(English Edition) 2023年第1期97卷 226-242页

作者： MENg Wen LIN weiren CHEN Qunce LI Yonghua Institute of geophysics China Earthquake AdministrationBeijing 100081China Key Laboratory of Earthquake Source Physics China Earthquake AdministrationBeijing 100081China Key Laboratory of Active Tectonics and geological Safety Ministry of Natural ResourcesInstitute of GeomechanicsChinese Academy of Geological SciencesBeijing 100081China graduate School of Engineering Kyoto UniversityKyotoJapan

In situ stress measurement data was analyzed to estimate the temporal and spatial stress variations at shallow depths in the Longmenshan fault zone(LMSF),prior to and following the 2008 Wenchuan earthquake(WCEQ).Analysis of the stress field related to fault strength and behavior is useful for understanding geodynamic processes and conducting hazard *** shallow stress changes after the WCEQ show clear along-strike *** of stress orientation rotations have a negative correlation with the horizontal principal stress ratios and the WCEQ apparently reduced the magnitude difference between horizontal principal *** stress magnitudes and orientation distribution relative to the fault strike into account,we propose an intermediate-strength of LMSF,with a friction coefficient generally constrained between 0.35 and *** addition,high-pressure fluids in the fault zone reduce the effective normal stress and to a certain degree weaken the fault *** accumulated stress over a certain period following release of the WCEQ indicates the start of another earthquake *** changing crustal stress field makes the LMSF stable or slipping optimally during geodynamic *** segmentation feature of the shallow crustal stress field in the LMSF may imply a different tectonic loading and seismic release processes along the *** southwestern section to the epicenter of the WCEQ favors the occurrence of future earthquakes,as highμm in a state of critical failure was present in this area,which indicates that the Wenchuan and Lushan earthquakes did not release the accumulated stress to a sufficient extent there.

关键词： stress variation in situ stress measurement fault strength hazard assessment Longmenshan fault zone

Immunotherapy of hepatocellular carcinoma: strategies for combinatorial intervention

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2019年第9期62卷 1138-1143页

作者： Mengxin Tian Yinghong Shi weiren Liu Jia Fan Department of Liver Surgery & Transplantation Center Liver Cancer InstituteZhongshan HospitalFudan University/Key Laboratory of Carcinogenesis and Cancer Invasion of Ministry of EducationShanghai 200032China Institute of Biomedical Sciences Fudan UniversityShanghai 200032China

Hepatocellular carcinoma(HCC) is the most frequent primary liver cancer,leading to 74.6 thousand deaths *** prognosis of HCC over the last few decades has remained unsatisfactory,and over half of patients with early-stage HCC develop recurrence by the time of *** intervention has emerged as a novel,effective treatment to delay the progression of aggressive tumors and suppress tumor recurrence and ***,few clinical immunotherapy trials have been conducted in HCC patients,and there is an unmet need for novel therapeutic *** combination of conventional treatments with specific immunotherapeutic approaches may dramatically improve the efficacy of HCC treatment and the clinical outcome of HCC *** this review,we briefly summarize immunotherapy strategies and discuss new advances in combined immunotherapeutic approaches for the treatment of patients with liver cancer.

关键词： hepatocellular carcinoma immunotherapy immune checkpoint inhibitor strategy combination therapy

Angular velocity estimation using characteristics of star trails obtained by star sensor for spacecraft

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2021年第1期64卷 201-214页

作者： Xiaolin NINg Pingping CHEN Yueqing HUANg weiren WU Jiancheng FANg School of Instrumentation Science & Opto-electronics Engineering Beihang University Lunar Exploration and Space Program Center China National Space Administration

Many studies have been conducted about angular velocity estimation using star sensors, and fairly good performance is achieved when the spacecraft is working at low-dynamic environments. However,when the spacecraft rotates at a large angular velocity, the star image will become blurred, which makes it difficult to identify and recognize star centroids, which, in turn, reduces the accuracy of angular velocity estimation. Therefore, to solve the problem with angular velocity estimation in highly dynamic situations,this research studies a method of angular velocity estimation using blurred star images. The length and ending point coordinates of star trails obtained from these blurred star images are used for a series of processes, which includes the pre-processing of blurred star images, determination of starting and ending points, thinning and selection of star trails, and calculation of trail lengths. Simulations show that the effectiveness of the proposed method in highly dynamic situations and the angular velocity estimation errors in constant and sinusoidal variation are reduced by at least 66% and 62%, respectively, compared with those of the traditional method.

关键词： angular velocity estimation star sensor blurred star images star trail characteristics unscented Kalman filter

Investigation on the development of deep space exploration

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2012年第4期55卷 1086-1091页

作者： WU weiren LIU WangWang QIAO Dong JIE Degang School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Center of Lunar Exploration and Aerospace Engineering Beijing 100037China

Deep space exploration is the term used for the exploration of the Moon and the celestial bodies or space beyond the Moon, which is an important part of human space activities. Firstly, the development of deep space exploration (not including the Moon) during the last few decades is summarized. Secondly, the development trend of different space countries and regions is analyzed. Then the experience and enlightenment of deep space exploration are briefly discussed. Some suggestions for China's future deep space exploration are given in the end.

关键词： deep space exploration space program trend of development enlightenment

在线全文

学校读者我要写书评

暂无评论

煤气化细渣疏水-亲水双液炭/灰分离实验

矿产综合利用 2024年第3期45卷 63-69页

作者：薛中华董连平樊民强杨崇义王建成鲍卫仁太原理工大学矿业工程学院山西太原030024 太原理工大学煤科学与技术教育部与山西省重点实验室山西太原030024

这是一篇矿业工程领域的论文。煤气化细渣是煤气化过程中产生的一种固体废物,其中残炭严重制约了其资源化利用,从煤气化细渣中提取残炭是一个紧迫的问题。本研究应用疏水-亲水双液分离技术来提取煤气化细渣中残碳,其主要的影响因素有搅... 详细信息

这是一篇矿业工程领域的论文。煤气化细渣是煤气化过程中产生的一种固体废物,其中残炭严重制约了其资源化利用,从煤气化细渣中提取残炭是一个紧迫的问题。本研究应用疏水-亲水双液分离技术来提取煤气化细渣中残碳,其主要的影响因素有搅拌速度、搅拌时间、疏水液体用量、矿浆浓度、矿浆温度和疏水液体种类。疏水-亲水双液分离技术对煤气化细渣有优异的提碳降灰效果,其碳产品的灰分可达30%以下,灰质产品的灰分可达95%以上。通过表征分析揭示了分离机理,结果表明残炭对煤油的吸附强度远超灰质,使得煤油处理过的残炭疏水性大幅度增加,容易被油相捕获。本研究可为煤气化细渣的高效提碳降灰提供重要指导,有助于实现煤气化固废的综合利用。

关键词：矿业工程煤气化细渣疏水液体团聚疏水-亲水双液分选

Synthesis and luminescence properties of Mn4+-dopant Ca14Zn6ga10-xAlxO35solid solution

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2018年第3期28卷 301-307页

作者： Yiyang Zhou weiren Zhao Chongrui Lu Zifeng Liao School of Physics and Optoelectronic Engineering Guangdong University of Technology

Mn4+-activated oxide phosphors,owing to their desirable spectral features,eco-friendly and low cost,are emerging as a new class of non-rare-earth red phosphors for warm white ***,these phosphors possess low photoluminescence quantum efficiency excited by blue chip *** we report an isostructural solid solution of Ca14Zn6ga10-xAlxO35:0.15Mn4+（0≤x≤10）synthesized by a traditional solidstate reaction *** microstructure and luminescent performance of this red-emitting phosphor are investigated in detail with the aids of X-ray diffraction,diffuse reflection spectra,photoluminescence spectra/decay/QE,and temperature-dependent PL/QE *** shift of energy peaks of4A2→4T1and4A2→4T2transition is illustrated by the Tanabe–Sugano diagram and the configurational coordinate *** crystal field strength（Dq）and the Racah parameters（B and C）are carefully calculated to estimate the nephelauxetic effectβ*** we achieve external and internal quantum efficiencies as high as26.1%and 40.3%for Ca14Zn6ga6Al4O35:0.15Mn4+excited by 466 nm,the highest one ever reported in Mn4+activated oxide phosphors under the similar condition.

关键词： Crystal phase Quantum efficiency Red emission Blue shift

Overview of deep space laser communication

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2018年第4期61卷 7-18页

作者： weiren WU Ming CHEN Zhe ZHANg Xiangnan LIU Yuhui DONg School of Aerospace Engineering Beijing Institute of Technology Beijing Research Institute of Telemetry

The deep space probe is a vital technology for observing and exploring the universe. It is thus intensifying as an aerospace research focus on an international scale. Despite improving the frequency band,the conventional microwave communication technique has difficulty satisfying the increased demand for the enormous volume of scientific data returning to the Earth. With a carrier frequency that is several orders of magnitude higher than the microwave, free-space optical communication is a robust and promising method for achieving both high bit rates and long distances in deep space communication. In this article, the history of this technology is summarized and the objective laws are formulated, while key techniques and development trends are analyzed. Finally, useful concepts and suggestions are proposed for the development of deep space laser communication in China.

关键词： deep space communication deep space observation development process free space communication laser communication

Comparison of potentials between genotype-based selection and genotypic value-based selection of quantitative traits

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2002年第24期47卷 2080-2083页

作者： weiren Wu Yuanchang Zhou Weiming Li Fujian Agr & Forestry Univ Coll Crop Sci Fuzhou 350002 Peoples R China

According to the difference of selection criteria, methods of marker-assisted selection (MAS) of quantitative traits can be divided into genotype-based selection (gS) and genotypic value-based selection (gVS). By means of computer simulation, potentials of the two methods were compared. Results showed that the two methods had similar basic laws and their efficiencies were not significantly different except that gS behaved better in the case where the number of QTLs was large and QTL effects were equal. From the application point of view, combination of gS and gVS should be the development direction of MAS research in the future.

关键词： quantitative trait marker-assisted selection genotypebased selection genotypic value-based selection potential.

Assessment and sequencing of air target threat based on intuitionistic fuzzy entropy and dynamic VIKOR

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2018年第2期29卷 305-310页

作者： ZHANg Kun KONg weiren LIU Peipei SHI Jiao LEI Yu ZOU Jie School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China Science and Technology on Electro-Optic Control Laboratory Luoyang 471009China

In view of the fact that traditional air target threat assessment methods are difficult to reflect the combat characteristics of uncertain, dynamic and hybrid formation, an algorithm is proposed to solve the multi-target threat assessment problems. The target attribute weight is calculated by the intuitionistic fuzzy entropy(IFE) algorithm and the time series weight is gained by the Poisson distribution method based on multi-times data. Finally,assessment and sequencing of the air multi-target threat model based on IFE and dynamic Vlse Kriterijumska Optimizacija I Kompromisno Resenje(VIKOR) is established with an example which indicates that the method is reasonable and effective.

关键词： threat assessment intuitionistic fuzzy entropy(IFE) dynamic Vlse Kriterijumska Optimizacija I Kompromisno Resenje(VIKOR) poisson distribution time series weight