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Journal of harbin Institute of Technology(New Series) 2014年第3期21卷 24-29页

作者： Ke yang Xu-yang Wang Tong Ge Chao Wu School of Naval Architecture Ocean and Civil EngineeringShanghai Jiaotong University

It will still in lack of a simulation platform used to learn the walking of underwater quadruped walking robot. In order to alleviate this shortage,a simulation platform for the underwater quadruped walking robot based on Kane dynamic model and CPG-based controller is constructed. The Kane dynamic model of the underwater quadruped walking robot is processed with a commercial package MotionGenesis Kane 5. 3. The forces between the feet and ground are represented as a spring and damper. The relation between coefficients of spring and damper and stability of underwater quadruped walking robot in the stationary state is studied. The CPG-based controller consisted of Central Pattern Generator( CPG) and Pd controller is presented,which can be used to control walking of the underwater quadruped walking robot. The relation between CPG parameters and walking speed of underwater quadruped walking robot is investigated. The relation between coefficients of spring and damper and walking speed of underwater quadruped walking robot is studied. The results show that the simulation platform can imitate the stable walking of the underwater quadruped walking robot.

关键词： underwater quadruped walking robot MotionGenesis Kane 5.3 CPG

Research and application of flood detention modeling for ponds and small reservoirs based on remote sensing data

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Science China(Technological Sciences) 2011年第8期54卷 2138-2144页

作者： CAO MingLiang ZhOU huiCheng ZhANG Chi ZhANG AiJing LI huiYun yang yang School of hydraulic Engineering Dalian University of Technology Dalian 116024 China Sichuan Provincial Investigation Design & Research Institute of Water Conservancy & Hydropower Chengdu 610072 China

This paper proposes a method of small reservoir flood detention modeling that utilizes data from the American land resources satellite Landsat TM/ETM+. Precipitation and potential evapotranspiration are taken as the control conditions in this method on the basis of basin terrain classification. The objective of this method is to solve the question of a small-scale water conservancy project’s influence on flood forecasting precision, which can be used in the basin with multitudinous small reservoirs in the upstream region and can help estimate non-runoff data for small reservoir runoff. Taking the 20060826 flood as an example, the flood detention quantity of 19 small reservoirs is modeled. The results show that the absolute error of the total flood detention quantity is 0.2×10 4 m 3 , and the relative error is 0.12%. The flood detention quantity of small reservoirs in the entire basin is then modeled using this method, and the primary flood forecasting model is adjusted. After adjustment, the precision is significantly improved, with the relative error decreasing from 31.8% to 10.1%.

关键词： remote sensing data small reservoir flood detention modeling

Progress in synthesis and application of zwitterionic Gemini surfactants

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Frontiers of Materials Science 2019年第3期13卷 242-257页

作者： Yuqiao ChENG yang yang Chunrong NIU Zhe FENG Wenhui ZhAO Shuang LU School of Chemistry and Chemical Engineering Tianjin Polytechnic UniversityTianjin 300387China Library Tianjin Polytechnic UniversityTianjin 300387China

Zwitterionic Gemini surfactants have the Gemini molecular structure in which there are both multiple lipophilic groups and multiple hydrophilic ***,their hydrophilic groups have different *** to the special molecular structure,this kind of surfactants possesses excellent properties,including high surface activities,isoelectric point(IP),low critical micelle concentration(CMC),less toxicity,low irritating,biodegradability,bioactive,interface modification,and so *** this review,synthetic strategies of three kinds of zwitterionic Gemini surfactants,i.e.,an ioniccationic,cationic-nonionic and anionic-nonionic Gemini surfactants,are discussed,and their potential applications in life sciences,chemical industry and enhanced oil recovery(EOR)are *** future development is also prospected.

关键词： zwitterionic Gemini surfactant high performance synthesis application chemical industry

Evaluation of Latest TMPA and CMORPh Precipitation Products with Independent Rain Gauge Observation Networks over high-latitude and Low-latitude Basins in China

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Chinese Geographical Science 2016年第4期26卷 439-455页

作者： JIANG Shanhu REN Liliang YONG Bin hONG yang yang Xiaoli YUAN Fei State Key Laboratory of hydrology-Water Resources and hydraulic Engineering Hohai University School of Civil Engineering and Environmental Sciences School of Meteorology University of Oklahoma

The Tropical Rainfall Measuring Mission （TRMM） Multi-satellite Precipitation Analysis （TMPA） and National Oceanic and Atmospheric Administration （NOAA） Climate Prediction Center （CPC） morphing technique （CMORPh） are two important multi-satellite precipitation products in TRMM-era and perform important functions in GPM-era. Both TMPA and CMORPh systems simultaneously upgraded their retrieval algorithms and released their latest version of precipitation data in 2013. In this study, the latest TMPA and CMORPh products （i.e., Version-7 real-time TMPA （T-rt） and gauge-adjusted TMPA （T-adj）, and Version- 1.0 real-time CMORPh （C-rt） and Version-l.0 gauge-adjusted CMORPh （C-adj）） are evaluated and intercompared by using independent rain gauge observations for a 12-year （2000--2011） period over two typical basins in China with different geographical and climate conditions. Results indicate that all TMPA and CMORPh products tend to overestimate precipitation for the high-latitude semiarid Laoha River Basin and underestimate it for the low-latitude humid Mishui Basin. Overall, the satellite precipitation products exhibit superior performance over Mishui Basin than that over Laoha River Basin. The C-adj presents the best performance over the high-latitude Laoha River Basin, whereas T-adj showed the best performance over the low-latitude Mishui Basin. The two gauge-adjusted products demonstrate potential in water resource management. however, the accuracy of two real-time satellite precipitation products demonstrates large variability in the two validation basins. The C-rt reaches a similar accuracy level with the gauge-adjusted satellite precipitation products in the high-latitude Laoha River Basin, and T-rt performs well in the low-latitude Mishui Basin. The study also reveals that all satellite precipitation products obviously overestimate light rain amounts and events over Laoha River Basin, whereas they underestimate the amount and events over Mishui Basin. The findings of

关键词： satellite precipitation Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) Cli-mate Prediction Center morphing technique (CMORPh) precision evaluation

Effects of graded fiber level and caecectomy on metabolizable energy value and amino acid digestibility in geese

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Journal of Integrative Agriculture 2016年第3期15卷 629-635页

作者： yang Jing ZhAI Shuang-shuang WANG Yong-chang WANG Shen-shen yang Zhi-peng yang Lin WANG Wen-ce College of Animal Science South China Agricultural University

This study was carried out to evaluate the effects of graded levels of fiber from rice hull and the caecectomy on metabolizable energy（ME） and amino acid digestibility（AAd） in 42 Wuzong geese（21 intact and 21 caecectomized）. The experiment was a 3×2 factorial randomized design with 3 fiber levels and 2 treatments of geese（caecectomized and intact）. Each of the 3 diets was tube-fed（60 g） to 7 caecectomized and 7 intact adult Wuzong geese that had been fasted for 24 h. Excreta were collected for the next 48 h. The same geese were also fasted for estimation of endogenous losses of amino acids（AA） and energy after short period recovery. AA content and metabolizable energy value were determined in the excreta. In general, significant effects were found for fiber levels on apparent digestibility of Thr, Leu, Pro, Glu,Val, Ala and total AA（P〈0.05）. Apparent metabolizable energy（AME） and true metabolizable energy（TME） were both significantly influenced by increased fiber levels（P〈0.01）. Compared with caecectomized geese, markedly increases of AME and TME were found in intact geese（P〈0.01 for AME and P 〈0.05 for TME）, but no difference in the AAd were found between intact and caecectomized geese（P〉0.05）, except for Lys and Try（P〈0.05）. These observations suggested that dietary fiber level played an important role in digestibility of AAd and ME. Intact geese should be chosen for the nutrient evaluation of feedstuffs in practice, resulting from the significant difference between caecectomized and intact geese.

关键词： fiber level amino acid digestibility metabolizable energy geese caecectomy

PRNU Extraction from Stabilized Video:A Patch Maybe Better than a Bunch

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Computer Systems Science & Engineering 2021年第1期36卷 189-200页

作者： Bin Ma Yuanyuan hu Jian Li Chunpeng Wang Meihong yang yang Zheng Qilu University of Technology(Shandong Academy of Sciences) Shandong Provincial Key Laboratory of Computer NetworksJinan250353China Shandong Computer Science Center Shandong Provincial Key Laboratory of Computer NetworksJinan250014China University of Connecticut MansfieldCT06269USA

This paper presents an algorithm to solve the problem of Photo-Response Non-Uniformity(PRNU)noise facing stabilized *** stabilized video undergoes in-camera processing like rolling shutter ***,misalignment exists between the PRNU noises in the adjacent frames owing to the global and local frame registration performed by the in-camera *** misalignment makes the reference PRNU noise and the test PRNU noise unable to extract and match *** design a computing method of maximum likelihood estimation algorithm for extracting the PRNU noise from stabilized video ***,unlike most prior arts tending to match the PRNU noise in whole frame,we propose a new patch-based matching strategy,aiming at reducing the influence from misalignment of frame the PRNU *** extracting the reference PRNU noise and the test PRNU noise,this paper adopts the reference and the test PRNU overlapping patch-based *** is different from the traditional matching *** paper conducts different experiments on 224 stabilized videos taken by 13 smartphones in the VISION *** area under curve of the algorithm proposed in this paper is 0.841,which is significantly higher than 0.805 of the whole frame matching in the traditional *** results show good performance and effectiveness the proposed strategy by comparing with the prior arts.

关键词： Photo-response non-uniformity(PRNU) stabilized video frames maximum likelihood estimation patch

high-strength composite yarns derived from oxygen plasma modified super-aligned carbon nanotube arrays

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Nano Research 2013年第3期6卷 208-215页

作者： haoming Wei yang Wei yang Wu Liang Liu Shoushan Fan Kaili Jiang department of Physics & Tsinghua-Eoxconn Nanotechnology Research Center Tsinghua University Beijing 100084 China department of Materials Science and Engineering Tsinghua University Beijing 100084 China

Spinning carbon nanotube （CNT） yarns from super-aligned carbon nanotube （SACNT） arrays is a promising approach to fabricate high-strength fibers. however the reported tensile strengths of the as-prepared fibers are far below that of an individual CNT. It is therefore still a challenge to improve their mechanical strengths. here we report that the tensile strengths and Young＇s moduli can be further improved to 2.2 GPa and 200 GPa respectively, if we first treat the SACNT array with oxygen plasma by using a reactive ion etching （RIE） facility, then dry spin yarns from it and make composite fibers with polyvinyl alcohol. According to the experimental results obtained using scanning electron microscopy （SEM）, Raman spectroscopy and X-ray photoelectron spectroscopy （XPS）, the improvement is attributed to the oxygen RIE process, as it can create functional groups on the outer walls of CNTs and thus improve the interaction between the CNTs and the polymer molecules.

关键词： carbon nanotube yarns super-aligned carbonnanotube array 02 plasma mechanical properties

Near-Threshold Wide-Voltage design Review

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Tsinghua Science and Technology 2023年第4期28卷 696-718页

作者： Yan Zhao Jun yang Chao Chen Weiwei Shan Peng Cao Yongliang Zhou Ziyu Li Tai yang National Application Specific Integrated Circuit(ASIC)Center Southeast UniversityNanjing 210096China

This paper presents a comprehensive review of near-threshold wide-voltage designs on memory,resilient logic designs,low voltage Radio Frequency(RF)circuits,and timing *** the prosperous development of wearable applications,low power consumption has become one of the primary challenges for IC *** improve the power efficiency,the prefer scheme is to operate at an ultra low voltage of Near Threshold Voltage(NTV).For the performance variation and degradation,a self-adaptive margin assignment technique is proposed in the low *** proposed technique tracks the circuit states in real time and dynamically allocates voltage margins,reducing the minimum supply voltage and achieving higher energy *** self-adaptive margin assignment technique can be used in Static Random Access Memory(SRAM),digital circuits,and analog/RF *** on the self-adaptive margin assignment technique,the minimum voltage in the 40 nm CMOS process is reduced to 0.6 V or even lower,and the energy efficiency is increased by 3–4 times.

关键词： Near Threshold Voltage(NTV) wide-voltage memory resilient logic design low voltage Radio Frequency(RF) timing analysis

Soil aggregation and aggregate associated organic carbon and total nitrogen under long-term contrasting soil management regimes in loess soil

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Journal of Integrative Agriculture 2015年第12期14卷 2405-2416页

作者： XIE Jun-yu XU Ming-gang Qiangjiu Ciren yang yang ZhANG Shu-lan SUN Ben-hua yang Xue-yun College of Resources and Environment Northwest A&F University Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of Agriculture Northwest A&F University National Engineering Laboratory for Improving Quality of Arable Land Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences Agriculture and Animal husbandry in Cona County department of Agronomy Hetao College

This study investigated the effects of three contrasting soil management regimes and different nutrient treatments on the distribution of water-stable aggregates（〉2, 1–2, 0.5–1, 0.25–0.5, and 〈0.25 mm） and associated soil organic carbon（SOC） and total nitrogen（TN） content in loess soil. A 21-yr long-term experiment was performed, in which soil management regimes include cropland abandonment（Abandonment）, bare fallow（Fallow） and wheat-fallow cropping（Cropping）. Under Cropping, the following nutrient treatments were employed： control（CK, no nutrient input）, nitrogen only（N）, nitrogen and potassium（NK）, phosphorus and potassium（PK）, NP, NPK, and manure（M） plus NPK（MNPK）. Results demonstrated that Abandonment significantly increased the content of soil macro-aggregates（〉0.25 mm） and mean weight diameter（MWd） at 0–10 and 10–20 cm soil horizons compared with Cropping, whereas Fallow yielded lower values of above two parameters. Abandonment increased SOC and TN contents in all aggregate sizes by 17–62% and 6–60%, respectively, at 0–10 cm soil layer compared with Cropping. Conversely, Fallow decreased SOC and TN contents in all aggregates by 7–27% and 7–25%, respectively. Nevertheless, the three soil management regimes presented similar SOC contents in all aggregates at 10–20 cm soil horizon. Only Cropping showed higher TN content in 〉0.5 mm aggregates than the two other regimes. Consequently, Abandonment enhanced the partitioning proportions of SOC and TN in 〉1 mm macro-aggregates, and Fallow promoted these proportions in micro-aggregates compared with Cropping. Under Cropping, long-term fertilization did not affect the distribution of aggregates and MWd values compared with those under CK, except for NPK treatment. Fertilizer treatments enhanced SOC and TN contents in aggregates at all tested soil depths. however, fertilization did not affect the partitioning proportions of SOC and TN contents in all aggregates compared with CK. Comprehensive results showed that different

关键词： cropland abandonment bare fallow wheat-fallow water-stable aggregate aggregate stability

Approximation for Ruin Probability in the Sparre Andersen Model with Interest

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Acta Mathematicae Applicatae Sinica 2006年第2期22卷 333-344页

作者： Ji-yang Tan Xiang-qun yang department of Mathematics Hunan Normal University Changsha 410081 China

We consider the Sparre Andersen model modified by the inclusion of interest on the surplus. Approximation for the ultimate ruin probability is derived by rounding. And upper bound and lower bound are also derived by rounding-down and rounding-up respectively. According to the upper bound and lower bound, we can easily obtain the error estimation of the approximation. Applications of the results to the compound Poisson model are given.

关键词： Sparre Andersen model compound Poisson model force of interest ruin probability