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基于同步数字系列(SDH)的数字网络中的抖动和漂动控制
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作者 王铁 《有线传输技术译文》 1993年第1期23-27,共5页
关键词 SDH 数字网络 抖动 漂动 控制
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浮漂动了动──贺《中国钓鱼》百期
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作者 王建国 《中国钓鱼》 1998年第10期36-37,共2页
关键词 漂动 读书人 合订本 浙江东南 小白条 分工合作 童年生活 庆典活动 竞答 1992年
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漂动的海藻
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作者 王兆福 《少年月刊(小学低年级)》 2011年第3期16-16,共1页
像鹿角,头上嵌,身上还有梅花斑。人们叫它鹿角鱼,尾巴竖起像蒲扇。
关键词 小学 课外阅读 阅读材料 漂动的海藻》
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漂动浅深诗意浓
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作者 黄显著 《中国钓鱼》 2010年第6期50-50,共1页
江河作伴钓江风,此癖人嫌我独钟。他慕深居当隐士,我欣垂钓脑轻松。竿抛远近文章大,漂动浅深诗意浓。喜看红花衬绿叶,风光无限醉其中。
关键词 诗歌 文学作品 现代文学 漂动浅深诗意浓》
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New digital drive phase control for improving bias stability of silicon MEMS gyroscope 被引量:3
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作者 夏国明 杨波 王寿荣 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期47-51,共5页
In order to improve the bias stability of the micro-electro mechanical system(MEMS) gyroscope and reduce the impact on the bias from environmental temperature,a digital signal processing method is described for impr... In order to improve the bias stability of the micro-electro mechanical system(MEMS) gyroscope and reduce the impact on the bias from environmental temperature,a digital signal processing method is described for improving the accuracy of the drive phase in the gyroscope drive mode.Through the principle of bias signal generation,it can be concluded that the deviation of the drive phase is the main factor affecting the bias stability.To fulfill the purpose of precise drive phase control,a digital signal processing circuit based on the field-programmable gate array(FPGA) with the phase-lock closed-loop control method is described and a demodulation method for phase error suppression is given.Compared with the analog circuit,the bias drift is largely reduced in the new digital circuit and the bias stability is improved from 60 to 19 °/h.The new digital control method can greatly increase the drive phase accuracy,and thus improve the bias stability. 展开更多
关键词 silicon micro-electro mechanical system(MEMS) gyroscope bias drift drive phase control field-programmable gate array(FPGA)
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从PDH的局间时钟同步过渡到SDH的局间时钟同步
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作者 蒋厚云 《电信网技术》 2002年第5期31-33,44,共4页
分析了PDH局间同步与SDH局间同步的差异,讨论了在SDH局间同步时需要关注的问题,并给出了相关建议。
关键词 PDH 局间时钟同步 SDH 漂动 漂移转移 时钟监测 同步数字系列
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香格里拉
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作者 金鸿为 陈勇 丁煜伦 《民族音乐》 2003年第6期25-25,共1页
关键词 雪山 雪域高原 中速 透明 阳光 百灵鸟 拉索 湖水 漂动 草滩
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香格里拉
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作者 金鸿为 钱康宁 《民族音乐》 1999年第2期13-13,共1页
关键词 方方 梅里雪山 地方 高原 草原 漂动 心灵 草滩 金子 透明
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SPICE model of trench-gate MOSFET device
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作者 刘超 张春伟 +1 位作者 刘斯扬 孙伟锋 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期408-414,共7页
A novel simulation program with an integrated circuit emphasis(SPICE) model developed for trench-gate metal-oxide-semiconductor field-effect transistor(M OSFET)devices is proposed. The drift region resistance was ... A novel simulation program with an integrated circuit emphasis(SPICE) model developed for trench-gate metal-oxide-semiconductor field-effect transistor(M OSFET)devices is proposed. The drift region resistance was modeled according to the physical characteristics and the specific structure of the trench-gate MOSFET device. For the accurate simulation of dynamic characteristics, three important capacitances, gate-to-drain capacitance Cgd, gate-to-source capacitance Cgsand drain-to-source capacitance Cds, were modeled, respectively, in the proposed model. Furthermore,the self-heating effect, temperature effect and breakdown characteristic were taken into account; the self-heating model and breakdown model were built in the proposed model; and the temperature parameters of the model were revised. The proposed model is verified by experimental results, and the errors between measured data and simulation results of the novel model are less than 5%. Therefore, the model can give an accurate description for both the static and dynamic characteristics of the trench-gate MOSFET device. 展开更多
关键词 trench-gate metal-oxide-semiconductor field-effect transistor(MOSFET) simulation program with integrated circuit emphasis(SPICE) model drift region resistance model dynamic model
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池溏
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作者 爱德华.索马斯 刘忠良 《语文世界(上旬刊)》 2000年第5期13-13,共1页
关键词 山东莱阳 爱德华 芦苇 海湾 漂动 太阳 月落 云朵 微风
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邮海帆影点点情
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作者 谭世光 《上海集邮》 1995年第3期33-33,共1页
每当我望着繁星满天的夜空,就会情不自禁地想到海上漂动的点点白帆…… 帆船自古以来,除了作为交通运输工具之外,还列入了体育比赛项目。帆船运动就是利用风帆力量推动船只,在规定距离内比赛航速的运动。1900年第二届奥运会已把它列入... 每当我望着繁星满天的夜空,就会情不自禁地想到海上漂动的点点白帆…… 帆船自古以来,除了作为交通运输工具之外,还列入了体育比赛项目。帆船运动就是利用风帆力量推动船只,在规定距离内比赛航速的运动。1900年第二届奥运会已把它列入正式比赛项目了。 展开更多
关键词 帆船运动 奥运会 体育比赛 比赛项目 交通运输工具 漂动 纪念邮票 影点 航速 英国
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Pharmacokinetics of two modified release system of dipyridamole in beagle dogs
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作者 张志宏 王昶光 +3 位作者 孙光美 李宁 彭博 潘卫三 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第4期297-302,共6页
A novel floating osmotic pump controlled release system (FOP) and traditional matrix sustained release tablets (MT) of dipyridamole (DIP) were characterized in terms of pharmacokinetics, drug release, and in vit... A novel floating osmotic pump controlled release system (FOP) and traditional matrix sustained release tablets (MT) of dipyridamole (DIP) were characterized in terms of pharmacokinetics, drug release, and in vitro-in vivo correlation. In vivo study was performed by a three-crossover study in six beagle dogs relative to the conventional tablet (CT). A HPLC method for the determination of DIP in the plasma was developed. Cumulative percent of absorption fraction was compared to that of in vitro cumulative release. Both FOP and MT displayed obvious extended release characteristic in vivo while FOP showed a better extended release behavior. The bioavailability of FOP was higher than that of MT and a zero-order release linear correlation of DIP between fraction absorbed in vivo and fraction dissolved in vitro was established for FOP while not for MT. The results indicated the existence of an absorption window in upper part of the GI track of DIP, which meant that floating system could be excellent for the drug delivery. In addition, the in vitro model was a good choice for depicting in vivo absorption and for optimization of the formulation of FOP if it is needed to be bio-equivalent to MT. 展开更多
关键词 DIPYRIDAMOLE FLOATING Osmotic pump Matrix tablets PHARMACOKINETICS In vitro-in vivo correlation
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The Joint Distribution of the Maximum Excursion and the Minimum Excursion for Brownian Motion with Drift
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作者 LUe Yu-hua XU Run 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期57-62,共6页
In this paper, we discuss the problem of extreme value for Brownian motion with positive drift. We obtain the joint distribution of the maximum excursion and the minimum excursion.
关键词 Brownian motion ruin time the first hitting time the last exit time maximum excursion minimum excursion
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Hole Mobility in Poly (N-vinylcarbazole) Thin Film Based on Silicium
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作者 CHENBaijun WANGXiaowei 《Semiconductor Photonics and Technology》 CAS 1997年第4期296-300,共5页
The mobilities of holes in thin,spin-casting films of poly( N -vinylcarbazole)(PVK) based on silicium are measured using a time-of-flight (TOF) technique.The drift of hole mobility is strongly dependent on the elect... The mobilities of holes in thin,spin-casting films of poly( N -vinylcarbazole)(PVK) based on silicium are measured using a time-of-flight (TOF) technique.The drift of hole mobility is strongly dependent on the electric field and temperature.At room temperature and an electric field of 2×10 5 V·cm -1 ,the effective mobility of hole is 7.14×10 -6 cm 2·V -1 ·s -1 ,in a 200 nm thick sample. 展开更多
关键词 MOBILITY Organic Semiconductor Time of Flight
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A data-driven method to predict future bottlenecks in a remanufacturing system with multi-variant uncertainties 被引量:2
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作者 XUE Zheng LI Tao +2 位作者 PENG Shi-tong ZHANG Chao-yong ZHANG Hong-chao 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第1期129-145,共17页
The remanufacturing system is remolding the manufacturing industry by bringing scrapped products back to such a condition that reintegrated performance is just as good as new.The remanufacturing environment is feature... The remanufacturing system is remolding the manufacturing industry by bringing scrapped products back to such a condition that reintegrated performance is just as good as new.The remanufacturing environment is featured by a far deeper level of uncertainty than new manufacturing,such as probabilistic routing files,and highly variable processing time.The stochastic disturbances result in the production bottlenecks,which constrain the productivity of the job shop.The uncertainties in the remanufacturing process cause the bottlenecks to shift when the workshop is processing.Considering this outstanding problem,many researchers try to optimize the production process to mitigate dynamic bottlenecks toward a balanced state.This paper proposes a data-driven method to predict bottlenecks in the remanufacturing system with multi-variant uncertainties.Firstly,discrete event simulation technology is applied to establish a simulation model of the remanufacturing production line and calculate the bottleneck index to identify bottlenecks.Secondly,a data-driven method,auto-regressive moving average(ARMA)model is employed to predict the bottlenecks in the system based on real-time data captured by the Arena software.Finally,the proposed prediction method is verified on real data from the automobile engine remanufacturing production line. 展开更多
关键词 bottleneck identification dynamic bottleneck remanufacturing system auto-regressive moving average model
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Moving Target Tracking Based on LogGabor Wavelet and Mean-shift Algorithm
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作者 DU Xian-yan HAN Xiao-jun LU Wei-wei 《Semiconductor Photonics and Technology》 CAS 2009年第2期81-85,96,共6页
Tracking moving target from image or video sequence is a hot research topic in computer vision. An algorithm based on LogGabor wavelet and Mean-shift has been proposed for moving target tracking under fixed camera set... Tracking moving target from image or video sequence is a hot research topic in computer vision. An algorithm based on LogGabor wavelet and Mean-shift has been proposed for moving target tracking under fixed camera setting and complicated environment. Phase coherency of LogGabor wavelet facilitates to extract the edge of moving target and check noise. According to the edge detection,the starting location of Mean-shift can be estimated using the target center coordinate. Eventually,a real-time moving target can be extracted by doing iterative matching pursuit,and experimental results proved the effectiveness of the method proposed. 展开更多
关键词 Mean-shift algorithm phase congruency LogGabor wavelet transformation target tracking
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Thiopurine use associated with reduced B and natural killer cells in inflammatory bowel disease 被引量:1
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作者 James D Lord Donna M Shows 《World Journal of Gastroenterology》 SCIE CAS 2017年第18期3240-3251,共12页
To identify which blood and mucosal lymphocyte populations are specifically depleted by thiopurine use in vivo.METHODSThe thiopurines azathioprine and 6-mercaptopurine have been a mainstay of inflammatory bowel diseas... To identify which blood and mucosal lymphocyte populations are specifically depleted by thiopurine use in vivo.METHODSThe thiopurines azathioprine and 6-mercaptopurine have been a mainstay of inflammatory bowel disease (IBD) therapy for decades, but their mechanism of action in vivo remains obscure. Although thiopurines are lymphotoxic at high doses, and have been reported to cause T cell apoptosis in vitro, their ability to control IBD at lower doses suggests that they may selectively deplete particular lymphocyte populations. Blood cells from 19 IBD patients on a thiopurine, 19 IBD patients not on a thiopurine, and 38 matched healthy control subjects were analyzed by multiple multi-color flow cytometry panels to quantify the immune cell subsets contained therein, both as a percent of cells, and as an absolute cell count. Similar analyses were performed on colon biopsies from 17 IBD patients on a thiopurine, 17 IBD patients not on a thiopurine, and 49 healthy screening colonoscopy recipients.RESULTSComplete blood counts revealed lower lymphocyte, but not monocyte or granulocyte, counts in IBD patients who were taking thiopurines at the time of sampling. This reduction was restricted to CD3-negative lymphocytes, wherein both natural killer (NK) and B cells were significantly reduced among thiopurine recipients. Among CD19+ B cells, the transitional B cells were particularly depleted, being nearly absent in both blood and colon biopsies of thiopurine recipients. No differences were associated with thiopurine use in CD8+ T cells, mucosa-associated invariant T (MAIT) cells, invariant natural killer T (iNKT) cells, gamma/delta T cells, Th1, Th17, regulatory T cells (Tregs) or naïve CD4+ T cells. However, patients with IBD had significantly more circulating FOXP3+, Helios+ Tregs and fewer iNKT and MAIT cells than healthy controls.CONCLUSIONThiopurine use is associated with reduced B and NK cell, but not T cell, subpopulations in the blood of IBD patients. 展开更多
关键词 THIOPURINE AZATHIOPRINE MERCAPTOPURINE LYMPHOCYTE Natural killer cell Transitional B cell Inflammatory bowel disease
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Thermo-Magneto-Electric Currents with Dynamical Magnetization Inhomogeneities
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作者 Santosh Kumar Kudtarkar 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第9期504-512,共9页
We study the effect of potential and thermal gradient induced non-equilibrium magnetization in quasi1-d itinerant magnets.A semi-phenomenological theory is employed in conjunction with the drift-diffusion model forthi... We study the effect of potential and thermal gradient induced non-equilibrium magnetization in quasi1-d itinerant magnets.A semi-phenomenological theory is employed in conjunction with the drift-diffusion model forthis study.Using the methods of non-equilibrium thermodynamics,we derive the transport currents correspondingto charge,heat,and magnetization flows in the presence of non-equilibrium magnetization textures.It is shown howtime-dependent magnetic textures give rise to charge and thermal currents even in the absence of external potential andthermal gradients through spin pumping.The presence of dynamical textures also affect the thermodynamic parametersof the system.As an application,we consider the case of a helimagnet. 展开更多
关键词 current and temperature driven spin pumping THERMOELECTRIC thermomagnetic
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Coherent Point Drift Registration Combined with Image Feature and its Application
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作者 ZHANG Jiu-lou LI Chun-li +2 位作者 FENG Qian-jin CHEN Wu-fan YANG Wei 《Chinese Journal of Biomedical Engineering(English Edition)》 2013年第4期148-153,共6页
A key step of constructing active appearance model is requiring a set of appropriate training shapes with well-defined correspondences.In this paper,we introduce a novel point correspondence method(FB-CPD),which can i... A key step of constructing active appearance model is requiring a set of appropriate training shapes with well-defined correspondences.In this paper,we introduce a novel point correspondence method(FB-CPD),which can improve the accuracy of coherent point drift(CPD) by using the information of image feature.The objective function of the proposed method is defined by both of geometric spatial information and image feature information,and the origin Gaussian mixture model in CPD is modified according to the image feature of points.FB-CPD is tested on the 3D prostate and liver point sets through the simulation experiments.The registration error can be reduced efficiently by FB-CPD.Moreover,the active appearance model constructed by FB-CPD can obtain fine segmentation in 3D CT prostate image.Compared with the original CPD,the overlap ratio of voxels was improved from 88.7% to 90.2% by FB-CPD. 展开更多
关键词 active appearance model point set registration gaussian mixturemodel feature information
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INTERFERENCE CANCELLATION FOR MOBILE DISPERSIVE CHANNELS
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作者 Kazi Takpaya 《Journal of Electronics(China)》 2003年第5期371-377,共7页
A robust interference canceller for Multi-Carrier Code Division Multiple Access(MC-CDMA) using Orthogonal Frequency Division Multiplexing (OFDM) in Rayleigh fading isproposed. This interference canceller is robust in ... A robust interference canceller for Multi-Carrier Code Division Multiple Access(MC-CDMA) using Orthogonal Frequency Division Multiplexing (OFDM) in Rayleigh fading isproposed. This interference canceller is robust in the sense that it cancels Inter-Carriers Inter-ference (ICI) and is suitable for use in dispersive channels. To come up the effects of the signaldispersion, Doppler shifts and delay spreads on the performance of MC-CDMA systems over mo-bile fading channels, this interference canceller exploits the merit of the orthogonal signaling andpilot signals to evaluate the channel parameters. This interface canceller is well suited to work initerative turbo interference cancellation. 展开更多
关键词 OFDM MC-CDMA Robust interference canceller Doppler shift Delay spread Pilot signal ID iterative turbo ICI cancellation
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