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液态物料定量灌装机的测量结果不确定度评定
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作者 朱以坤 《计量与测试技术》 2007年第4期50-50,53,共2页
本文介绍了检定液态物料定量灌装机常用方法“衡量法”及其测量不确定度的评定。
关键词 衡最法 液态物料定量灌装机 测量不确定度 检定
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The Maximum Ice Age Glaciation between the Karakorum Main Ridge (K_2) and the Tarim Basin and its Influence on Global Energy Balance 被引量:1
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作者 Matthias Kuhle 《Journal of Mountain Science》 SCIE CSCD 2005年第1期5-22,共18页
A modern research approach and working techniques in hitherto unexamined areas, produced the following results: 1). The tongues of deca- kilometre long Karakorum glaciers belong to temperate ice-streams with an an... A modern research approach and working techniques in hitherto unexamined areas, produced the following results: 1). The tongues of deca- kilometre long Karakorum glaciers belong to temperate ice-streams with an annual meltwater output. The short Aghil glaciers on the contrary are continental, arid and cold. 2). The present-day oscillations of the Karakorum glaciers are related to their own mass, and are contrary to and independent of the actual climate. Only the short glaciers, with steep tongue fronts, show a present-day positive balance. 3). C- dated Late Glacial moraines indicate14 a 400~800 m thick valley glacier at the former confluence point of the K2-, Sarpo Laggo- and Skamri glaciers. 4). From the evidence of transfluence passes with roches moutonnées, striae and the limits of glacial polishing, as well as moraines and erratics, a High Glacial at least 1200 m thick ice-stream network between the Karakorums and the Kuen Lun north slopes was reconstructed. The Shaksgam and Yarkand valleys were occupied by glaciers coming from west Tibet. The lowest-lying moraines are to be found in the foreland down to 2000 m, indicating a depression of the High Glacial (LGM) snowline (ELA) by 1300 m. 5). The approximately 10,000 measurements of the radiation balance at up to heights of 5500 m on K2 indicate that with incoming energy near the solar constant the reflection from snow- covered ice is up to 70% greater than from rock and rock waste surfaces. 6).These results confirm for the very dry western margins of Tibet an almost complete ice sheet cover in an area with subtropical energy balance, conforming with the Ice Age hypothesis of the author which is based upon the presence of a 2.4 million km2 Tibetan inland ice sheet. This inland ice developed for the first time when Tibet was uplifted over the snowline during the early Pleistocene. As the measured subtropical radiation balance shows, it was able to trigger the Quaternary Ice Ages. 展开更多
关键词 KARAKORUM Tibet ice age glaciation PALEOCLIMATE ice age theory high mountain geomorphology
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Soft Direct-Adaptation Based Bidirectional Turbo Equalization for MIMO Underwater Acoustic Communications 被引量:5
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作者 Junyi Xi Shefeng Yan +1 位作者 Lijun Xu Jing Tian 《China Communications》 SCIE CSCD 2017年第7期172-183,共12页
This paper proposes a soft direct-adaptation based bidirectional turbo equalizer for multiple-input multiple-output underwater acoustic communication systems. Soft, rather than hard, direct-adaptation based equalizer ... This paper proposes a soft direct-adaptation based bidirectional turbo equalizer for multiple-input multiple-output underwater acoustic communication systems. Soft, rather than hard, direct-adaptation based equalizer combined with the fast self-optimized least mean square algorithm is employed to achieve a faster convergence rate, and the second-order phase-locked loop is embedded into the equalizer to track the time-varying channel. Meanwhile, by utilizing a weighted linear combining scheme, the conventional soft direct-adaptation based equalizer is combined with the time-reversed soft direct-adaptation based equalizer to exploit bidirectional diversity and mitigate error propagation. Both the simulation and experimental results demonstrate that the soft direct-adaptation based bidirectional turbo equalizer outperforms the single-direction soft direct-adaptation based turbo equalizer, and achieves a faster convergence rate than the hard direct-adaptation based bidirectional turbo equalizer. 展开更多
关键词 soft direct-adaptation based turbo equalizer bidirectional turbo equalizer multipie-input multiple-output underwater acoustic communications
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Least-mean-square routing with load-balancing for wireless ad hoc networks
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作者 陈西豪 陈惠民 周伟 《Journal of Shanghai University(English Edition)》 CAS 2008年第2期131-135,共5页
Routing algorithm is a challenge for a mobile ad hoc network (MANET), but current routing protocols for MANETs consider the path with minimum number of hops as the optimal path to a given destination. This strategy ... Routing algorithm is a challenge for a mobile ad hoc network (MANET), but current routing protocols for MANETs consider the path with minimum number of hops as the optimal path to a given destination. This strategy does not balance the traffic load over a MANET, and may result in some disadvantages such as creating congested area, depleting power faster and enlarging time delay in the nodes with heavy duties. In this paper, we propose a routing scheme that balances the load over the network by selecting a path based on its mean load-square, the proposed routing metric can reflect not only the load of the path, but also the load distribution along the path. Simulation results show effectiveness of this routing scheme on balancing the load over all nodes in the network. 展开更多
关键词 ad hoc network ROUTING least-mean-square routing (LMSR) route REQuest (RREQ).
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Measurement and Correlation of Solubility for Propylene in 2-Propanol-Water Solutions
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作者 刘国柱 任永利 +1 位作者 米镇涛 吴玉龙 《Transactions of Tianjin University》 EI CAS 2003年第3期180-183,共4页
In order to obtain the solubility data of propylene in 2-propanol-water solutions, gas-liquid equilibrium (GLE) experiments were carried out at 303.15-333.15 K, 0.27-0.98 MPa in a static equilibrium still. The origina... In order to obtain the solubility data of propylene in 2-propanol-water solutions, gas-liquid equilibrium (GLE) experiments were carried out at 303.15-333.15 K, 0.27-0.98 MPa in a static equilibrium still. The original mass ratio of 2-propanol to water was 9∶1,8∶2,7∶3,1∶0, respectively. The equilibrium data were correlated with an empirical model and the regression of model parameters was completed by Gauss-Newton nonlinear least square (NLS). The average relative deviation (ARD) between the experimental and calculated value is 1.570 0, and the maximum relative deviation (MRD) is 4.820 0. In addition, a simple approach that correlated the model parameters with the system composition was also provided. 展开更多
关键词 SOLUBILITY PROPYLENE 2-propanol-water gas-liquid equilibrium(GLE)
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Clinical efficacy observation of thalamic pain treated with acupuncture under the guidance of evidence-based medicine 被引量:2
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作者 樊小农 张雪 +1 位作者 武连仲 王海荣 《World Journal of Acupuncture-Moxibustion》 2012年第3期1-5,17,共6页
Objective To study the feasibility of the crossover trial design and the minimal imbalance index random distribution method in the clinical small-sample-size randomized controlled trial(RCT) research of thalamic pai... Objective To study the feasibility of the crossover trial design and the minimal imbalance index random distribution method in the clinical small-sample-size randomized controlled trial(RCT) research of thalamic pain treated with acupuncture under the guidance of evidence-based medicine(EBM).Methods The crossover trial design was adopted.Eleven cases with the definite diagnosis were randomized into a program-I group(6 cases,treated with acupuncture before western medicine) and a program-II group(5 cases,treated with western medicine before acupuncture) according to the minimal imbalance index method.In the statistical analysis,the groups were named as an acupuncture group and a western medicine group separately,11 cases in each one.Acupuncture was applied to Xìmén(郄门 PC 4),Yīnxì(阴郄 HT 6),Xuèhǎi(血海 SP 10),etc.In the control treatment,Carbamazepine was prescribed for oral administration.Either the duration of treatment or the wash-out period was 10 days.The visual analogue scale(VAS) was adopted for the efficacy assessment.Results The total effective was 100.0%(11/11) after treatment in either group.The remarkably effective rates were 63.6%(7/11) and 36.4%(4/11) in the acupuncture group and the western medicine group separately,without statistically significant difference in comparison.Conclusion The crossover trial design and the minimal imbalance index distribution method can accomplish RCT of the clinical acupuncture and moxibustion research with the small sample size involved.They can provide the high-quality evidences for clinical acupuncture research.Acupuncture therapy can achieve the same therapeutic effect as Carbamazepine,the common western medicine,and the efficacy of it is potentially superior to that of western medicine. 展开更多
关键词 thalamic pain acupuncture therapy evidence-based medicine(EBM) crossover trial design random minimal imbalance index distribution method
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