资源类型

期刊论文 16

年份

2022 2

2021 1

2018 1

2017 1

2014 3

2012 2

2011 3

2010 2

2006 1

展开 ︾

关键词

GPS浮标 1

HY-2 1

两硬煤层 1

井帮位移 1

低角估计；甚高频雷达；复杂场景；多径效应；高度估计 1

冻结壁厚度 1

卫星高度计 1

反演算法 1

大采高综放 1

定标 1

平均温度 1

弦切面 1

掘砌段高 1

接触角 1

数值模拟 1

时差干扰降震 1

有效波高 1

段起爆药量 1

毛竹 1

展开 ︾

检索范围：

排序： 展示方式：

Yield-height correlation and QTL localization for plant height in two lowland switchgrass populations

Shiva O. MAKAJU, Yanqi WU, Michael P. ANDERSON, Vijaya G. KAKANI, Michael W. SMITH, Linglong LIU, Hongxu DONG, Dan CHANG

《农业科学与工程前沿（英文）》 2018年 第5卷 第1期   页码 118-128 doi: 10.15302/J-FASE-2018201

摘要： Switchgrass ( L.), as a model herbaceous crop species for bioenergy production, is targeted to improve biomass yield and feedstock quality. Plant height is a major component contributing to biomass yield. Accordingly, the objectives of this research were to analyze phenotypic variation for biomass and plant height and the association between them and to localize associated plant height QTLs. Two lowland switchgrass mapping populations, one selfed and another hybrid population established in the field at Perkins and Stillwater, Oklahoma, were deployed in the experiment for two years post establishment. Large genetic variation existed for plant biomass and height within the two populations. Plant height was positively correlated with biomass yield in the selfed population ( = 0.39, <0.0001) and the hybrid population ( = 0.41, <0.0001). In the selfed population, a joint analysis across all environments revealed 10 QTLs and separate analysis for each environment, collectively revealed 39 QTLs related to plant height. In the hybrid population, the joint analysis across overall environments revealed 35 QTLs and the separate analysis for each environment revealed 38 QTLs. The findings of this research contribute new information about the genetic control for plant height and will be useful for future plant breeding and genetic improvement programs in lowland switchgrass.

关键词： yield-height     QTL localization     lowland switchgrass    

HTML PDF 收藏

Influence of nozzle height to width ratio on ignition and NO

Liutao SUN, Yonghong YAN, Rui SUN, Zhengkang PENG, Chunli XING, Jiangquan WU

《能源前沿（英文）》 2021年 第15卷 第2期   页码 431-448 doi: 10.1007/s11708-021-0726-3

摘要： To improve the ignition behavior and to reduce the high NO emissions of blended pulverized fuels (PF) of semicoke (SC), large-scale experiments were conducted in a 300 kW fired furnace at various nozzle settings, i.e., ratios (denoted by / ) of the height of the rectangular burner nozzle to its width of 1.65, 2.32, and 3.22. The combustion tests indicate that the flame stability, ignition performance, and fuel burnout ratio were significantly improved at a nozzle setting of / = 2.32. The smaller / delayed ignition and caused the flame to concentrate excessively on the axis of the furnace, while the larger / easily caused the deflection of the pulverized coal flame, and a high-temperature flame zone emerged close to the furnace wall. NO emissions at the outlet of the primary zone decreased from 447 to 354 mg/m (O = 6%), and the ignition distance decreased from 420 to 246 mm when the / varied from 1.65 to 3.22. Furthermore, the ratio (denoted by / ) of the strong reduction zone area to the combustion reaction zone area was defined experimentally by the CO concentration to evaluate the reduction zone. The / rose monotonously, but its restraining effects on NO formation decreased as / increased. The results suggested that in a test furnace, regulating the nozzle / conditions sharply reduces NO emissions and improves the combustion efficiency of SC blends possessing an appropriate jet rigidity.

关键词： rectangular jet burner     nozzle height to width ratio     ignition characteristics     pyrolyzed semicoke (SC) and bituminous blend     NOx formation    

HTML PDF 收藏

Numerical analysis of nonlinear dynamic behavior of earth dams

Babak EBRAHIMIAN

《结构与土木工程前沿（英文）》 2011年 第5卷 第1期   页码 24-40 doi: 10.1007/s11709-010-0082-6

摘要： A numerical study is conducted to investigate the dynamic behavior of earth dams. The numerical investigation employs a fully nonlinear dynamic finite difference analysis incorporating a simple elastic perfectly plastic constitutive model to describe the stress-strain response of the soil and the Rayleigh damping to increase the level of hysteretic damping. The extended Masing rules are implemented into the constitutive model to explain more accurately the soil response under general cyclic loading. The soil stiffness and hysteretic damping change with loading history. The procedures for calibrating the constructed numerical model with centrifuge test data and also a real case history are explained. For the latter, the Long Valley (LV) earth dam subjected to the 1980 Mammoth Lake earthquake as a real case-history is analyzed and the obtained numerical results are compared with the real measurements at the site in both the time and frequency domains. Relatively good agreement is observed between computed and measured quantities. It seems that the Masing rules combined with a simple elasto-plastic model gives reasonable numerical predictions. Afterwards, a comprehensive parametric study is carried out to identify the effects of dam height, input motion characteristics, soil behavior, strength of the shell materials and dam reservoir condition on the dynamic response of earth dams. Three real earthquake records with different levels and peak acceleration values (PGAs) are used as input motions. The results show that the crest acceleration decreases when the dam height increases and no amplification is observed. Further, more inelastic behavior and more earthquake energy absorption are observed in higher dams.

关键词： earth dam     numerical     nonlinear response     dynamic analysis     earthquake     dam height    

HTML PDF 收藏

甚高频雷达复杂场景中目标高度和多径衰减联合估计 Research Articles

陈胜,赵永波,胡毅立,曹成虎,庞晓娇

《信息与电子工程前沿（英文）》 2022年 第23卷 第6期   页码 937-949 doi: 10.1631/FITEE.2100003

摘要：

由于多径效应的影响，甚高频雷达低角估计是雷达领域难题之一，尤其是在反射条件未知的复杂情况下，低角估计更难解决。针对这一问题，提出一种目标高度和多径衰减联合估计算法。该算法首先利用数据本身的特性估算反射系数幅度，当该幅度估计值很小时，认为没有反射信号，然后将反射系数的相位和直达信号与反射信号之间的相位差当作同一部分，即多径相位衰减，并对其进行搜索。推导了该算法的克拉美罗界。最后，计算机仿真和实测数据处理结果表明，该算法在复杂场景下具有良好估计性能，并且在仅有单次快拍的条件下仍能较好地工作。

关键词： 低角估计；甚高频雷达；复杂场景；多径效应；高度估计    

HTML PDF 收藏

基于HY-2高度计波形数据的高分辨率有效波高反演算法研究

王桂忠,张杰,苗洪利,李国强,王鑫

《中国工程科学》 2014年 第16卷 第6期   页码 60-64

摘要：

有效波高是描述海况的重要参量之一，利用高度计遥感获取有效波高已在海洋研究中获得广泛应用。本文基于海洋二号（HY-2）卫星高度计波形数据，发展了一种高分辨率有效波高反演算法，采用中误差对反演得到的20 Hz有效波高进行筛选，有效提高了测量精度。通过该方法对1 个轨的波形数据进行有效波高反演，统计结果表明：与针对1 s 回波反演的有效波高比较，利用该方法可将有效波高观测分辨率提高约15 倍，精度约为0.44 m；利用HY-2 高度计20 Hz 波形数据反演的有效波高精度可靠，可用其进行高分辨率的相关海洋研究。

关键词： HY-2     有效波高     反演算法     高分辨率    

HTML PDF 收藏

Numerical simulation of liquid falling film on horizontal circular tubes

Fengdan SUN, Songlin XU, Yongchuan GAO

《化学科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 322-328 doi: 10.1007/s11705-012-1296-z

摘要： The objective of this study is to investigate numerically the flow characteristics of falling film on horizontal circular tubes. Numerical simulations are performed using FLUENT for 2D configurations with one and two cylinders. The volume of fluid method is used to track the motion of liquid falling film and the gas-liquid interface. The effect of flow characteristics on heat and transfer coefficient may be remarkable, although it has been neglected in previous studies. The velocity distribution and the film thickness characteristics on the top tube, some special flow characteristics on the bottom tube, intertube flow modes and effect of liquid feeder height on flow characteristics have been studied. Our simulations indicate that 1) the velocity distributions of the upper and lower parts of the tube are not strictly symmetric and non-uniform, 2) the film thickness depends on flow rate and angular distributions, 3) the flow characteristics of the top tube are different from those of the bottom tube, 4) three principal and two intermediate transition modes are distinguished, and 5) the liquid feed height plays an important role on the formation of falling film. The numerical results are in a good agreement with the theoretical values by the Nusselt model and the reported results.

关键词： falling film     horizontal tube     flow characteristics     film thickness     liquid feeder height    

HTML PDF 收藏

深表土冻结壁变形规律

郭永富

《中国工程科学》 2011年 第13卷 第11期   页码 81-88

摘要：

利用ANSYS软件建立数学模型，分析不同地压、不同冻结壁厚度、不同冻结壁平均温度、不同开挖段高与冻结壁变形之间的关系。通过研究发现,井帮位移随冻结壁平均温度的降低、冻结壁厚度的增大而减小，随施工段高增大、地层地压值的增大而增大，且地压值的变化对冻结壁的变形影响最为显著。据此提出了深表土冻结壁应按变形条件进行设计，且施工段高是影响冻结壁稳定性的极为重要的参数，在施工中应严格控制。研究提出当冻结壁厚度为10 m左右，平均温度达到－20 ℃时，采取降低冻结壁平均温度的方式比增加冻结壁厚度能更加有效地提高冻结壁的

关键词： 井帮位移     冻结壁厚度     平均温度     掘砌段高    

HTML PDF 收藏

Genomic regions under selection for important traits in domestic horse breeds

Xuexue LIU, Yuehui MA, Lin JIANG

《农业科学与工程前沿（英文）》 2017年 第4卷 第3期   页码 289-294 doi: 10.15302/J-FASE-2017155

摘要： Horses were domesticated 5500 years ago, thousands of years later than other domestic animals; however, in this relatively short period, domestic horses have had a great impact on human history by accelerating civilization, revolutionizing warfare and advancing agricultural production. Modern breeding using marker-assisted selection has greatly accelerated breeding progress. Therefore, identification of genetic markers underlying the traits of interest in domestic horses is the basis for the modern breeding system. In this review, we present an overview of genetic mapping studies and genome wide analyses to identify the genomic regions targeted by positive selection for four important aspects of horses, coat color, racing performance, gait and height at withers. The locus, for example, has been shown to be the main gene responsible for chestnut color, and the locus has been shown to control the muscle fiber growth in racing breeds. The missense mutation in is the causal mutation for the alternate gaits in horses. Height at withers, a quantitative trait, was mapped to four major loci (3:105547002, 6:81481064, 9:75550059 and 11:232597 32) that can explain 83% of the height variations in domestic horses.

关键词： horse     coat color     racing performance     gait     height    

HTML PDF 收藏

Investigation on available wind energy at Tungku beach

M. G. YAZDANI, M. A. SALAM

《能源前沿（英文）》 2012年 第6卷 第3期   页码 275-279 doi: 10.1007/s11708-012-0194-x

摘要： In this paper, wind velocities and directions (sea and land) are recorded in different days and times. The data collected were compared with the weather data from the Brunei Darussalam Meteorological Service (BDMS) and the findings of other researchers and were found to be in good agreement. The potential of wind energy is predicted from the available data collected. The average generated power (forenoon and afternoon) is found to be 25 (mean) and 18 W (median), 101 (mean) and 73 W (median), 912 (mean) and 660 W (median), 10137 (mean) and 7331 W (median) for a rotor with a diameter of 2.5, 5, 15 and 50 m, respectively. The power density for wind farming is found to be 0.26 (mean) and 0.19 (median), 0.31 (mean) and 0.22 (median) for the rotor whose diameter is 2.5 and 50 m, respectively, while the average values are found to be 0.28 (mean) and 0.2 (median) for the rotor whose diameter is 5 and 15 m.

关键词： wind velocity     temperature     tower height     power density     Raleigh distribution     electrical power    

HTML PDF 收藏

Dynamic analysis of free-surface thin film flows driven by gravity over undulated substrate

Zhaomiao LIU, Xin LIU, Guobin WANG, Hong LIAO,

《机械工程前沿（英文）》 2010年 第5卷 第2期   页码 219-225 doi: 10.1007/s11465-010-0010-4

摘要： This paper studies thin film flows with free surfaces driven by gravity through two types of undulated planes: periodically sinusoidal plane and triangle. The substrate plane is fixed and inclined to a certain angle and the flow with a free surface. Through finite element method (FEM), commenced from Navier-Stokes equations and continuity equation, the exact numerical results of free-surface film flows are obtained through discretization solution to finite equations in flowing areas. Based on the numerical calculations, the streamlines and wall shearing stress during the flowing process are visualized via post-proceeding, and the streamlines separation, the onset and evolution of vortex near the substrate boundary during the flow are also analyzed. The influences from the waviness of the substrate planes profile, height of the triangle plane, and change of the film height on film flow dynamics properties are shown.

关键词： waviness     triangle height     film thickness     streamlines separation     vortex    

HTML PDF 收藏

Ribbed strip rolling by three-dimensional finite element method combining extremely thin array of elements

Zhengyi JIANG,

《机械工程前沿（英文）》 2010年 第5卷 第1期   页码 52-60 doi: 10.1007/s11465-009-0087-9

摘要： In this paper, a three-dimensional finite element modelling of the ribbed strip rolling is carried out, coupling the use of an extremely thin array of elements that is equivalent to the calculation of the additional shear deformation work rate occurred by the velocity discontinuity in the roll bite. The formulation of the finite element modelling by adding a rib inclined contact surface boundary condition is derived, and the performance of the proposed method is conducted. The simulated rib height, forward slip, and the pulling down of rib height have been compared with the measured values and are in good agreement. The equivalent strain rate of the rib was obtained in the simulation. The effect of the rib inclined angle on pulling down of rib height has also been discussed, which is helpful in optimizing the design of the rib inclined angle.

关键词： rib inclined contact boundary condition     ribbed strip     extremely thin elements     pulling down of rib height     finite element modelling    

HTML PDF 收藏

某露天采场爆破震动特性及减震技术研究

林大能,陈寿如,刘优平

《中国工程科学》 2006年 第8卷 第6期   页码 73-77

摘要：

为解决某露天采场高陡边坡受生产爆破震动的影响，根据该采场的岩石性质和爆破规模，对采场进行了爆破振动测试，得出了该区域爆破地震波的传播特性，揭示了该矿区的爆破振动速度与药量和测点位置的关系，爆破振动速度随相对高程的增大而存在放大效应，放大系数的变化率随高程的增加而减小；通过控制段起爆最大药量，采用时差干扰降震技术较好地解决了生产规模与震动安全控制问题；现场试验表明，该矿的最佳段差时间为15ms，平均降震率达到23.6%。

关键词： 露天采场     爆破震动     高程效应     段起爆药量     时差干扰降震    

HTML PDF 收藏

不同立杆高度毛竹材弦切面的润湿性能研究

张巧玲,周洪伟,梁廷斌,仝雪艳,曾钦志

《中国工程科学》 2014年 第16卷 第4期   页码 56-59

摘要：

本文研究了H2O、酚醛树脂胶黏剂（PF）、脲醛树脂胶黏剂（UF）和改性大豆蛋白胶（MSA）在毛竹材不同立杆高度弦切面的润湿性能，通过测定这些润湿液体在竹材弦切面上的接触角，建立润湿液体在毛竹材弦切面的动态润湿模型，分析毛竹材的不同高度对润湿液体动态润湿性能的影响，并对比分析各种润湿液体在毛竹材弦切面的润湿性能差异。

关键词： 毛竹     立杆高度     弦切面     接触角     润湿性    

HTML PDF 收藏

A method of determining flame radiation fraction induced by interaction burning of tri-symmetric propane fires in open space based on weighted multi-point source model

Jie JI, Junrui DUAN, Huaxian WAN

《能源前沿（英文）》 2022年 第16卷 第6期   页码 1017-1026 doi: 10.1007/s11708-020-0716-x

摘要： The interaction of multiple fires may lead to a higher flame height and more intense radiation flux than a single fire, which increases the possibility of flame spread and risks to the surroundings. Experiments were conducted using three burners with identical heat release rates (HRRs) and propane as the fuel at various spacings. The results show that flames change from non-merging to merging as the spacing decreases, which result in a complex evolution of flame height and merging point height. To facilitate the analysis, a novel merging criterion based on the dimensionless spacing / was proposed. For non-merging flames ( / >0.368), the flame height is almost identical to a single fire; for merging flames ( / ≤0.368), based on the relationship between thermal buoyancy and thrust (the pressure difference between the inside and outside of the flame), a quantitative analysis of the flame height, merging point height, and air entrainment was formed, and the calculated merging flame heights show a good agreement with the measured experimental values. Moreover, the multi-point source model was further improved, and radiation fraction of propane was calculated. The data obtained in this study would play an important role in calculating the external radiation of propane fire.

关键词： flame interaction     air entrainment     flame height     multi-point source model     thermal radiation    

HTML PDF 收藏

基于GPS的高度计海面高度定标浮标设计

陈春涛,闫龙浩,张晓旭,张倩,翟万林,朱建华

《中国工程科学》 2014年 第16卷 第6期   页码 109-112

摘要：

全球定位系统（GPS）浮标是高度计海面高度定标的重要仪器。本文介绍了GPS浮标的组成和工作原理，分别对GPS浮标的外型设计、舱体设计、密封性设计、供电设计做了详细介绍，最后利用数值模拟的方式，对设计的GPS浮标在3 级海况下的摇摆和升沉响应进行模拟试验。结果表明自主设计的GPS浮标能够满足海上高度计海面高度定标的需求。

关键词： 卫星高度计     定标     GPS浮标     数值模拟    

HTML PDF 收藏

标题 作者 时间 类型 操作

Yield-height correlation and QTL localization for plant height in two lowland switchgrass populations

Shiva O. MAKAJU, Yanqi WU, Michael P. ANDERSON, Vijaya G. KAKANI, Michael W. SMITH, Linglong LIU, Hongxu DONG, Dan CHANG

期刊论文

Influence of nozzle height to width ratio on ignition and NO

Liutao SUN, Yonghong YAN, Rui SUN, Zhengkang PENG, Chunli XING, Jiangquan WU

期刊论文

Numerical analysis of nonlinear dynamic behavior of earth dams

Babak EBRAHIMIAN

期刊论文

甚高频雷达复杂场景中目标高度和多径衰减联合估计

陈胜,赵永波,胡毅立,曹成虎,庞晓娇

期刊论文

基于HY-2高度计波形数据的高分辨率有效波高反演算法研究

王桂忠,张杰,苗洪利,李国强,王鑫

期刊论文

Numerical simulation of liquid falling film on horizontal circular tubes

Fengdan SUN, Songlin XU, Yongchuan GAO

期刊论文

深表土冻结壁变形规律

郭永富

期刊论文

Genomic regions under selection for important traits in domestic horse breeds

Xuexue LIU, Yuehui MA, Lin JIANG

期刊论文

Investigation on available wind energy at Tungku beach

M. G. YAZDANI, M. A. SALAM

期刊论文

Dynamic analysis of free-surface thin film flows driven by gravity over undulated substrate

Zhaomiao LIU, Xin LIU, Guobin WANG, Hong LIAO,

期刊论文

Ribbed strip rolling by three-dimensional finite element method combining extremely thin array of elements

Zhengyi JIANG,

期刊论文

某露天采场爆破震动特性及减震技术研究

林大能,陈寿如,刘优平

期刊论文

不同立杆高度毛竹材弦切面的润湿性能研究

张巧玲,周洪伟,梁廷斌,仝雪艳,曾钦志

期刊论文

A method of determining flame radiation fraction induced by interaction burning of tri-symmetric propane fires in open space based on weighted multi-point source model

Jie JI, Junrui DUAN, Huaxian WAN

期刊论文

基于GPS的高度计海面高度定标浮标设计

陈春涛,闫龙浩,张晓旭,张倩,翟万林,朱建华

期刊论文