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Diagnostic sensitivity of imaging modalities for hepatocellular carcinoma smaller than 2 cm 被引量:7
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作者 Keiji Mita Soo Ryang Kim +7 位作者 Masatoshi Kudo Susumu Imoto Taisuke Nakajima Kenji Ando Katsumi Fukuda Toshiyuki Matsuoka Yoko Maekawa Yoshitake Hayashi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第33期4187-4192,共6页
AIM:To compare the imaging results with histology and to evaluate the diagnostic sensitivity of imaging modalities for hepatocellular carcinoma(HCC)smaller than 2 cm.METHODS:Nodules smaller than 2 cm(n=34)revealed by ... AIM:To compare the imaging results with histology and to evaluate the diagnostic sensitivity of imaging modalities for hepatocellular carcinoma(HCC)smaller than 2 cm.METHODS:Nodules smaller than 2 cm(n=34)revealed by ultrasonography(US)in 29 patients with liver cirrhosis were analyzed.Histological diagnosis of HCC was performed by ultrasonographic guidance:moderately-differentiated HCC(n=24);well-differentiated HCC(n=10).The patterns disclosed by the four imaging modalities defined the conclusive diagnosis of HCC:(1)contrast-enhanced computed tomography(CECT),hypervascularity in the arterial phase and washout in the equilibrium phase;(2)Sonazoid contrast-enhanced US(CEUS),hypervascularity in the early vascular phase and defect in the Kupffer phase;(3)gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid(Gd-EOBDTPA)-enhanced magnetic resonance imaging(MRI),hypervascularity in the arterial phase and/or defect in the hepatobiliary phase;and(4)CT arterioportal angiography:hypervascularity by CT during arteriography and/ or perfusion defect by CT during arterial portography.RESULTS:Overall,the sensitivity of diagnosing HCC smaller than 2 cm was 52.9%(18/34)(95%CI:35.170.2)by CECT;67.6%(23/34)(95%CI:49.5-82.6)by Sonazoid CEUS;76.5%(26/34)(95%CI:58.8-89.3) by Gd-EOB-DTPA MRI;and 88.2%(30/34)(95%CI: 72.5-96.7)by CT arterioportal angiography.The diagnostic sensitivity of detecting moderately-differentiated HCC by CECT,Sonazoid CEUS,Gd-EOB-DTPA MRI and CT arterioportal angiography was 62.5%(15/24)(95%CI: 40.6-81.2),79.2%(19/24)(95%CI:57.8-92.9),75.0% (18/24)(95%CI:53.3-90.2)and 95.8%(23/24)(95% CI:78.9-99.9),respectively.A significant difference(P< 0.05)was observed between CECT and CT arterioportal angiography in all nodules.There was no difference between Sonazoid CEUS,Gd-EOB-DTPA MRI,and CT arterioportal angiography.The combined sensitivity of Sonazoid CEUS and Gd-EOB-DTPA MRI was 94.1%(32/34).CONCLUSION:Changing the main diagnostic modality for HCC smaller than 2 cm from CT arterioportal angiography to Sonazoid C 展开更多
关键词 Computed tomography arterioportal angi- ography Contrast-enhanced computed tomography Diagnostic sensitivity Gd-EOB-DTPA-enhanced magnetic resonance imaging Hepatocellular carcinoma smaller than 2 cm:Sonazoid contrast-enhanced ultrasonography
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高密度组装电气互联新技术原理与研究方法 被引量:7
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作者 谢庆 吴兆华 《电子工艺技术》 2003年第2期47-49,58,共4页
网络通信技术的高速发展围绕着小、轻、高速和高密度几个方向给IT市场提出了多样化的需求。介绍了高密度组装发展的现状和未来的发展趋势。CSP的研制使组装密度和性能得到提高 ,达到二维组装密度的极限 ;三维多芯片组装使组装密度达到... 网络通信技术的高速发展围绕着小、轻、高速和高密度几个方向给IT市场提出了多样化的需求。介绍了高密度组装发展的现状和未来的发展趋势。CSP的研制使组装密度和性能得到提高 ,达到二维组装密度的极限 ;三维多芯片组装使组装密度达到一个新的高度 ,高速性能大大提高 ,同时力求降低制造成本。 2 1世纪互联技术将继续沿着高密度和高速性方向发展。 展开更多
关键词 芯片尺寸封装 高密度组装 芯片叠层MCP CSP 发展趋势
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Smaller & Smarter: Score-Driven Network Chaining of Smaller Language Models
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作者 Gunika Dhingra Siddansh Chawla +1 位作者 Vijay K. Madisetti Arshdeep Bahga 《Journal of Software Engineering and Applications》 2024年第1期23-42,共20页
With the continuous evolution and expanding applications of Large Language Models (LLMs), there has been a noticeable surge in the size of the emerging models. It is not solely the growth in model size, primarily meas... With the continuous evolution and expanding applications of Large Language Models (LLMs), there has been a noticeable surge in the size of the emerging models. It is not solely the growth in model size, primarily measured by the number of parameters, but also the subsequent escalation in computational demands, hardware and software prerequisites for training, all culminating in a substantial financial investment as well. In this paper, we present novel techniques like supervision, parallelization, and scoring functions to get better results out of chains of smaller language models, rather than relying solely on scaling up model size. Firstly, we propose an approach to quantify the performance of a Smaller Language Models (SLM) by introducing a corresponding supervisor model that incrementally corrects the encountered errors. Secondly, we propose an approach to utilize two smaller language models (in a network) performing the same task and retrieving the best relevant output from the two, ensuring peak performance for a specific task. Experimental evaluations establish the quantitative accuracy improvements on financial reasoning and arithmetic calculation tasks from utilizing techniques like supervisor models (in a network of model scenario), threshold scoring and parallel processing over a baseline study. 展开更多
关键词 Large Language Models (LLMs) smaller Language Models (SLMs) FINANCE NETWORKING Supervisor Model Scoring Function
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Significant“smaller is softer”in amorphous silicon via irradiation-me diate d surface modification 被引量:1
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作者 Yuecun Wang Lin Tian +1 位作者 Meng Li Zhiwei Shan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第35期106-112,共7页
“Smaller is softer”is a reverse size dependence of strength,defying the“smaller is stronger”tenet.It usually results from surface-mediated displacive or diffusive deformation and is mainly found in some ultra-smal... “Smaller is softer”is a reverse size dependence of strength,defying the“smaller is stronger”tenet.It usually results from surface-mediated displacive or diffusive deformation and is mainly found in some ultra-small-scale(below tens of nanometers)metallic materials.Here,making use of the surface modifi-cation via ion beam irradiation,we bring the“smaller is softer”into being in a covalently-bonded,hard,and brittle material-amorphous Si(a-Si)at a much larger size regime(<∼500 nm).It is manifested as the transition from the quasi-brittle failure to the homogeneous plastic deformation as well as the de-creasing yield stress with sample volume reduction at the submicron-scale regime.An analytical model of hard core/superplastic shell has been proposed to explain the artificially-controllable size-dependent softening.This surface engineering pathway via ion irradiation is not only of particular interest to tai-lor the strength and deformation behaviors in small-sized a-Si or other covalently-bonded amorphous solids but also of practical relevance to the utility of a-Si in microelectronics and microelectromechanical systems. 展开更多
关键词 Amorphous silicon Micropillars smaller is softer” Ion irradiation
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Brain Tumor Segmentation through Level Based Learning Model
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作者 K.Dinesh Babu C.Senthil Singh 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期709-720,共12页
Brain tumors are potentially fatal presence of cancer cells over a human brain,and they need to be segmented for accurate and reliable planning of diag-nosis.Segmentation process must be carried out in different regio... Brain tumors are potentially fatal presence of cancer cells over a human brain,and they need to be segmented for accurate and reliable planning of diag-nosis.Segmentation process must be carried out in different regions based on which the stages of cancer can be accurately derived.Glioma patients exhibit a different level of challenge in terms of cancer or tumors detection as the Magnetic Resonance Imaging(MRI)images possess varying sizes,shapes,positions,and modalities.The scanner used for sensing the location of tumors cells will be sub-jected to additional protocols and measures for accuracy,in turn,increasing the time and affecting the performance of the entire model.In this view,Convolutional Neural Networks deliver suitable models for efficient segmentation and thus delivered promising results.The previous strategies and models failed to adhere to diversity of sizes and shapes,proving to be a well-established solution for detecting tumors of bigger size.Tumors tend to be smaller in size and shape during their premature stages and they can easily evade the algorithms of Convolutional Neural Network(CNN).This proposal intends to furnish a detailed model for sensing early stages of cancer and hence perform segmentation irrespective of the current size and shape of tumors.The size of networks and layers will lead to a significant weightage when multiple kernel sizes are involved,especially in multi-resolution environments.On the other hand,the proposed model is designed with a novel approach including a dilated convolution and level-based learning strat-egy.When the convolution process is dilated,the process of feature extraction deals with multiscale objective and level-based learning eliminates the shortcoming of previous models,thereby enhancing the quality of smaller tumors cells and shapes.The level-based learning approach also encapsulates the feature recon-struction processes which highlights the sensing of small-scale tumors growth.Inclusively,segmenting the images is performed with better accuracy and 展开更多
关键词 Glioma detection SEGMENTATION smaller tumour GROWTH machine learning feature analysis
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Cure for HIV/AIDS with Medicinal Synthetic Aluminum-Magnesium Silicate {Al<sub>4</sub>(SiO<sub>4</sub>)<sub>3</sub>+ 3Mg<sub>2</sub>SiO<sub>4</sub>→ 2Al<sub>2</sub>Mg<sub>3</sub>(SiO<sub>4</sub>)<sub>3</sub>}—A Case Report 被引量:1
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作者 M.C.O.Ezeibe N.K.Aneke +11 位作者 T.N.Obarezi F.Onyeachonam M.E.Sanda I.J.Ogbonna E.Kalu U.N.Njoku M.Udobi O.E.Ekundayo O.I.O.Ifenkwe M.C.Igwe T.O.Ogbodo U.C.Agu 《World Journal of AIDS》 2019年第3期161-166,共6页
HIV/AIDS is an immune deficiency disease, caused by an RNA virus (positively charged pathogen). It is still being regarded as mysteriously incurable but in Nigeria many patients have been cured (they became HIV-antibo... HIV/AIDS is an immune deficiency disease, caused by an RNA virus (positively charged pathogen). It is still being regarded as mysteriously incurable but in Nigeria many patients have been cured (they became HIV-antibody and antigen negative) by exploiting electrostatic attraction between pathogens and opposite electrical charges that are on Nanoparticles of Medicinal synthetic Aluminum-magnesium silicate (MSAMS) and by using antioxidants to relieve oxidative stress. To confirm the cure, as permanent, a patient (adult male) whose CD4 count increased (P < 0.05) from 685 to 820 while his viral load became undetectable (<20) and he became HIV-negative (antibody and antigen) following the treatment, was tested, every month, post treatment, for HIV-antibody. He has remained HIV-negative for 10 months without being on any antiretroviral medicine (ARV). Longest window period (period HIV-infected person may test antibody-negative) is only 6 months. These results confirm that treatment with the MSAMS and antioxidants normalizes immunity and terminates HIV-infections. 展开更多
关键词 MSAMS Antiviral/Anticancer Features/Mechanisms Size (smaller than Viruses/Cancer-Cells) Electrostatic-Bonding Immune-Stimulation Efficacy-Enhancing
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一种新型线性调频信号产生方式的研究 被引量:2
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作者 任飞飞 袁关东 +1 位作者 马志扬 赵岩 《微波学报》 CSCD 北大核心 2014年第S1期58-60,共3页
线性调频信号(LFM)是一种常用的雷达信号,因其具有良好的脉冲压缩特性及分辨能力,LFM信号在高分辨、相控阵、合成孔径等方面具有广泛应用。针对当前雷达导引头日益复杂的应用背景,本文介绍了一种小型化、低成本线性调频信号产生方式。... 线性调频信号(LFM)是一种常用的雷达信号,因其具有良好的脉冲压缩特性及分辨能力,LFM信号在高分辨、相控阵、合成孔径等方面具有广泛应用。针对当前雷达导引头日益复杂的应用背景,本文介绍了一种小型化、低成本线性调频信号产生方式。基于本文的研究,将该技术应用在雷达导引头上,得到了很好的应用。作为一种宽带的线性调频信号产生方式,该技术还能广泛应用于其他频段的捷变频雷达、电子对抗等领域。 展开更多
关键词 线性调频信号 小型化 低成本
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A STUDY ON MESOSCALE VORTICITY PROPAGATION IN A TYPHOON-LIKE VORTEX
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作者 罗哲贤 《Acta meteorologica Sinica》 SCIE 2004年第2期179-194,共16页
By using an f-plane barotropic quasi geostrophic model in the rectangular coordinates with a grid spacing of 5 km,ten experiments whose integration time is 36 hours are performed in order to study the interaction betw... By using an f-plane barotropic quasi geostrophic model in the rectangular coordinates with a grid spacing of 5 km,ten experiments whose integration time is 36 hours are performed in order to study the interaction between a typhoon vortex and a mesoscale vortex whose initial center position is located at 2 rnorthwest to the typhoon center,where ris the radius of maximum wind of the typhoon vortex. Results show that the interaction can create a pair of smaller scale vortices or lumps,which extend from the outside region of the typhoon to near its center,resulting in the inward propagation of mesoscale vorticity.In this process,the vorticity concentration of the mesoscale vortex may appear.The coexistence of the propagation and the concentration makes the increase of vorticity in the inside region i.e.a more intensive typhoon.Meanwhile,the intensity of the lump with positive vorticity oscillates with time,with the oscillation period being several hours,the distance from the typhoon center to the lump center also has a similar oscillation period,which reduces the oscillation of typhoon intensity.In the case of stronger circular basic flow,the interaction can make the intensification of typhoon more obviously. In addition,in some parametric conditions,the interaction may break down the continuous vorticity zone,exhibiting a cluster of smaller vorticity lumps. 展开更多
关键词 mesoscale vortex TYPHOON pair of smaller scale vortices intensity change
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Exploration and determination of the principles of rotary-percussive underground slimhole drilling 被引量:1
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作者 Shadrina Anastasija Saruev Lev 《International Journal of Mining Science and Technology》 SCIE EI 2014年第2期245-249,共5页
A possibility of the efficient use of rotary percussive drilling to provide drilling smaller diameter holes(40–70 mm) both in mining and prospecting is disclosed herein. A new construction designed for the nipple thr... A possibility of the efficient use of rotary percussive drilling to provide drilling smaller diameter holes(40–70 mm) both in mining and prospecting is disclosed herein. A new construction designed for the nipple thread connection is described. The relative amplitude variation, change of power pulse time and energy in their propagation throughout the drilling tool are determined. A possibility of the efficient power pulse transfer along the drill string to the rock destruction tools with new nipple connections which allow automating the make-up and breakout system of drill pipe was supported by experiments. 展开更多
关键词 Rotary-percussive drilling smaller diameter holes Drill string Nipple thread connection Power pulse Percussive energy
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Valence electronic structure of tantalum carbide and nitride 被引量:1
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作者 FAN ChangZeng SUN LiLing +4 位作者 WEI ZunJie MA MingZhen LIU RiPing ZENG SongYan WANG WenKui 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期737-741,共5页
The valence electronic structures of tantalum carbide (TaC) and tantalum nitride (TaN) are studied by using the empirical electronic theory (EET). The results reveal that the bonds of these compounds have covalent,met... The valence electronic structures of tantalum carbide (TaC) and tantalum nitride (TaN) are studied by using the empirical electronic theory (EET). The results reveal that the bonds of these compounds have covalent,metallic and ionic characters. For a quantitative analysis of the relative strength of these components,their ionicities have been calculated by implanting the results of EET to the PVL model. It has been found that the ionicity of tantalum carbide is smaller than that of tantalum nitride. The EET results also reveal that the covalent electronic number of the strongest bond in the former is larger than that of the latter. All these suggest that the covalent bond of TaC is stronger than that of TaN,which coincides to that de-duced from the first-principles method. 展开更多
关键词 TAC TAN valence electronic structure IONICITY
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浅谈划小核算单位后产品成本核算的方法 被引量:1
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作者 程相斌 《洛阳工学院学报》 1991年第2期85-89,共5页
本文探讨了大中型企业为完善经济责任制、提高经济效益,在划小核算单位后,根据企业的生产工艺特点、组织管理要求及各种成本核算方法的优缺点,提出了一种简化产品成本核算程序、比较准确地计算各种产品实际成本的成本核算方法——“定... 本文探讨了大中型企业为完善经济责任制、提高经济效益,在划小核算单位后,根据企业的生产工艺特点、组织管理要求及各种成本核算方法的优缺点,提出了一种简化产品成本核算程序、比较准确地计算各种产品实际成本的成本核算方法——“定额成本逐步结转、成本差异平行结转”法。 展开更多
关键词 核算单位 产品 成本核算 企业活力
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Multisatellite observations of smaller mesoscale eddy generation in the Kuroshio Extension
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作者 Fangjie Yu Meiyu Wang +1 位作者 Sijia Qian Ge Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第9期137-148,共12页
Smaller mesoscale eddies(SMEs)have an important effect on the transmission of ocean temperatures,salinity,energy,and marine biochemical processes.However,traditional altimeters,the dominant sensors used to identify an... Smaller mesoscale eddies(SMEs)have an important effect on the transmission of ocean temperatures,salinity,energy,and marine biochemical processes.However,traditional altimeters,the dominant sensors used to identify and track eddies,have made it challenging to observe SMEs accurately due to resolution limitations.Eddies drive local upwelling or downwelling,leaving signatures on sea surface temperatures(SSTs)and chlorophyll concentrations(Chls).SST can be observed by spaceborne infrared sensors,and Chl can be measured by ocean color remote sensing.Therefore,multisatellite observations provide an opportunity to obtain information to characterize SMEs.In this paper,an eddy detection algorithm based on SST and Chl images is proposed,which identifies eddies by characterizing the spatial and temporal distribution of SST and Chl data.The algorithm is applied to characterize and analyze SMEs in the Kuroshio Extension.Statistical results on their distribution and seasonal variability are shown,and the formation processes are preliminarily discussed.SMEs generation may be contributed by horizontal strain instability,the interaction of topographic obstacles and currents,and wind stress curl. 展开更多
关键词 Kuroshio Extension smaller mesoscale eddy eddy detection algorithm multisatellite remote sensing
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口腔科精小器械灭菌现状分析与对策
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作者 钟慕华 莫福有 《医学信息(下旬刊)》 2011年第6期419-420,共2页
目的:探讨口腔科精小器械理想的消毒灭菌方法。方法,通过分析目前口腔科精小器械的灭菌状况,严格按照正确操作程序,对口腔科精小器械进行清洗、消毒、包装、压中蒸汽灭菌及监测。结果:口腔科精小器械灭菌后,各项生物监测均为阴性... 目的:探讨口腔科精小器械理想的消毒灭菌方法。方法,通过分析目前口腔科精小器械的灭菌状况,严格按照正确操作程序,对口腔科精小器械进行清洗、消毒、包装、压中蒸汽灭菌及监测。结果:口腔科精小器械灭菌后,各项生物监测均为阴性,灭菌率达100%,且无不良事件的发生。蛄论:严格按正确操作程序对口腔科精小器械处理、灭菌率高、效果可靠、同时也确保了医疗器械的使用安全。 展开更多
关键词 精小 器械 灭菌
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New glowing dyes in vivo imaging with wavelengths beyond 1500 nm
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作者 Jing Yang Xuechuan Hong 《Science China Chemistry》 SCIE EI CAS CSCD 2019年第1期7-8,共2页
Near-infrared (NIR)fluorescence imaging in the second near-infrared region (NIR-H,1000-1700 nm)is an important and attractive imaging method for biomedical research and clinical applications,and can achieve high spati... Near-infrared (NIR)fluorescence imaging in the second near-infrared region (NIR-H,1000-1700 nm)is an important and attractive imaging method for biomedical research and clinical applications,and can achieve high spatial resolution, high signal-to-background ratio (SBR)and deeper tissue imaging owing to nearly zero auto-fluorescence background and tissue scattering .Smaller optical sub-window such as NIR-IIb (1500-1700 nm)has provided significant improvements in in vivo fluorescence imaging clarity and penetration depth. 展开更多
关键词 NEAR-INFRARED (NIR)fluorescence smaller optical FLUORESCENCE
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Faults and Claims about Thermal Environments in Relation to Energy Saving Measures in Smaller Office Buildings
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作者 Noriko Umemiya Taiji Obuchi Ryota Matsui 《Journal of Civil Engineering and Architecture》 2014年第4期413-424,共12页
Building equipment, energy-saving systems, and claims of inappropriate indoor thermal environments were analyzed in relation to the floor area using responses to a questionnaire survey of service managers of 157 build... Building equipment, energy-saving systems, and claims of inappropriate indoor thermal environments were analyzed in relation to the floor area using responses to a questionnaire survey of service managers of 157 buildings built in Osaka, Kyoto and Hyogo prefectures in Kinki area of Japan. Results show the following: (1) In smaller buildings (〈 5,000 m2), setting temperatures are higher in summer and lower in winter, effects of "uncomfortable radiation from windows" are greater, energy-saving systems decrease indoor thermal comfort, but claims of "hot" and "cold" are fewer; (2) Claims of "hot" and "cold" are unrelated to the setting temperature and whether the air-conditioning control system is central or local; (3) The adoption rates of mitigation of dress codes ("COOL-BIZ" and "WARM-BIZ") are higher than those of temperature mitigation of air conditioning. 展开更多
关键词 smaller office buildings energy management energy saving measures COOL-BIZ user claims of hot and cold.
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Particle and Nuclear Physics
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《Bulletin of the Chinese Academy of Sciences》 2019年第4期201-204,共4页
Our understanding of the microscopic universe has gone far beyond the atomic level—now we know even the neutron or proton, once thought to be "elementary particles", can be divided into smaller building blo... Our understanding of the microscopic universe has gone far beyond the atomic level—now we know even the neutron or proton, once thought to be "elementary particles", can be divided into smaller building blocks, for example quacks. Also known as highenergy physics, particle physics is dedicated to studying the subatomic structure and properties of matter, and understanding how such subnuclear particles interact with each other in high-energy conditions. 展开更多
关键词 PHYSICS smaller PARTICLES
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EH4在危机矿山隐伏金矿体定位预测中的应用研究 被引量:68
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作者 沈远超 申萍 +2 位作者 刘铁兵 李光明 曾庆栋 《地球物理学进展》 CSCD 北大核心 2008年第2期559-567,共9页
EH4连续电导率成像仪是快速高效的第四代数字化大地电磁探测仪器,基本配置(10Hz~100kHz)能测量地表向下1000m深度范围内地质体的连续视电导率值,我们对25个不同类型金属矿床进行了隐伏矿定位预测,取得了显著的效果.2D模式图能清晰地反... EH4连续电导率成像仪是快速高效的第四代数字化大地电磁探测仪器,基本配置(10Hz~100kHz)能测量地表向下1000m深度范围内地质体的连续视电导率值,我们对25个不同类型金属矿床进行了隐伏矿定位预测,取得了显著的效果.2D模式图能清晰地反映不同电性体的精细电阻率结构,经钻孔验证后显示:(1)火山晚期热液型金矿床,很好地反映了火山机构控矿的漏斗状形态,体现了矿体的垂向延深大于水平延长的成矿规律,矿化异常的电阻率较低(1~150Ω·m);(2)剪切带型金矿床,明显区分了矿化蚀变构造带和围岩,确认矿化异常在围岩中呈脉状分布,电阻率小于260Ω·m;(3)隐爆角砾岩型金矿床,清晰地反映了隐爆角砾岩体控矿所形成的对称矿(化)体,区分了隐爆角砾岩体和矿化蚀变带,矿化异常的电阻率较高(1000~2000Ω·m). 展开更多
关键词 EH4连续电导率成像仪 低电阻率 矿化异常 隐伏金矿体
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矫直机压弯量计算法的探讨 被引量:23
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作者 崔甫 施东成 《冶金设备》 1999年第1期1-6,共6页
随着计算机设定矫直机压弯量(俗称压下量)的精确化需要,初步提出一种解析方法和数值方法。并在大挠度压弯时把弹复挠度与残留挠度分开计算,在计算残留挠度时,将其作为假想外力作用所产生的等效挠度,再将此等效挠度分为弹性挠度与... 随着计算机设定矫直机压弯量(俗称压下量)的精确化需要,初步提出一种解析方法和数值方法。并在大挠度压弯时把弹复挠度与残留挠度分开计算,在计算残留挠度时,将其作为假想外力作用所产生的等效挠度,再将此等效挠度分为弹性挠度与弹塑性挠度使用数值积分法计算,可获得相当精确的结果。与现场经验值对比验证。 展开更多
关键词 矫直 压弯量 挠度 小变形压弯 矫直机 计算
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最小二乘方法用于多站测向定位的算法 被引量:22
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作者 徐济仁 薛磊 《电波科学学报》 EI CSCD 2001年第2期227-230,共4页
文中讨论了测向定位中的若干问题 ,包括双站交会定位及其定位误差分析、三站交会定位、多站交会定位 ,最后首次尝试将最小二乘方法和递推最小二乘方法用于多站测向定位的算法 ,对于提高测向定位的精度和简化运算量有很大的作用 ,有相当... 文中讨论了测向定位中的若干问题 ,包括双站交会定位及其定位误差分析、三站交会定位、多站交会定位 ,最后首次尝试将最小二乘方法和递推最小二乘方法用于多站测向定位的算法 ,对于提高测向定位的精度和简化运算量有很大的作用 ,有相当的实用性。 展开更多
关键词 最小二乘方法 多站测向定位算法 无线测向 通信对抗
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边缘区域扰动演变对台风结构的影响 被引量:12
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作者 罗哲贤 《大气科学》 CSCD 北大核心 1994年第5期513-519,共7页
在台风环流边缘区域给出不稳定模态的扰动四波分布作为初始场,用准地转正压模式实施四组数值积分,研究了边缘区域扰动演变及其对台风非对称结构及外区流型的影响。结果表明:线性平流对于外缘区域扰动的发展起主要作用。尸项导致一个... 在台风环流边缘区域给出不稳定模态的扰动四波分布作为初始场,用准地转正压模式实施四组数值积分,研究了边缘区域扰动演变及其对台风非对称结构及外区流型的影响。结果表明:线性平流对于外缘区域扰动的发展起主要作用。尸项导致一个气旋一反气旋涡旋对和非对称结构的形成。非线性平流则使外缘区域较小尺度的涡旋破碎,形成更小尺度的涡旋。在线性平流、β项和非线性平流的共同作用下,台风结构与外区形成象螺旋云系的分布。外缘区域扰动引起的结构变化,进而能影响到台风的移动路径。 展开更多
关键词 涡旋 台风 抗动演变 边缘区域
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