Results 11 to 20 of about 279 (112)
Shuitu Baochi Xuebao, 2023 为建立适用于我国不同区域生产建设项目工程堆积体土壤侵蚀预测模型,在通用土壤侵蚀模型(universal soil loss equation,USLE)框架下,室内概化模拟不同土壤质地、坡度坡长、砾石质量分数等工况下的工程堆积体,通过大量人工模拟降雨试验,修订模型各因子,构建工程堆积体土壤侵蚀量预测模型,并对其进行验证。研究明确工程堆积体标准小区及各因子定义及计算方法,提出采用土石质因子代替传统的土壤可蚀性因子以便更加符合工程堆积体实际,构建以幂函数计算的坡度、坡长因子 ...
王文龙 +4 more
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Growth characteristics of two morphologically similar varieties of Marsupenaeus japonicus under indoor cultivation environment [PDF]
, 2014 我国沿海日本囊对虾MArSuPEnAEuS JAPOnICuS群体资源可依据其头胸甲形态分为两种不同形态变异类型。文章对室内养殖环境中日本囊对虾2种形态变异类型f1群体不同性别对虾的体长和体质量进行了跟踪测量,研究其生长特性及其规律。结果表明:日本囊对虾体长和体质量呈幂函数关系,两群体雌、雄虾的体长、头胸甲长与体重的拟合参数b值皆近似为3,呈等速生长。拟合其VOn bErTAllAnffy生长方程如下,形态变异类型Ⅰ(♀):lT=15.932x[1–E–0.0067(T–26.5055)],WT=48 ...
毛勇 +4 more
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Relationship models between secant modulus and maximum and minimum principal stresses of nonlinear elastic rocks [PDF]
Stress-dependent elastic modulus (SDEM) of rocks is an important factor affecting the stress distribution of deep surrounding rocks. To quantitatively describe the rock SDEM, assuming rock as an isotropic nonlinear elastic body, its strain is decomposed ...
GAO Xiang1, 2 , ZHANG Qinghe2, 3 , YIN Zhiqiang1, LI Jingguo4
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Dianci bileiqi, 2022 为研究不同因素对电晕放电紫外成像检测的影响特性,以棒-板间隙模型为研究对象,利用CoroCAM504紫外成像仪采集了不同影响因素下交流放电的紫外视频信号。试验结果表明:放电光斑面积随观测距离的增加而减小,其变化曲线近似满足幂函数关系;在相同放电强度与观测距离下,光斑面积随增益的增加而增大,其变化趋势近似满足指数函数;放电光斑面积随观测角度的改变其大小无明显差异;光斑面积随温度的增加而增加,但具有明显的非线性;光斑面积随湿度的增加而减少,变化曲线近似满足幂函数关系;风速对电晕放电具有明显的削弱作用 ...
王胜辉 +4 more
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Prediction and uncertainty analysis of pollution flux of typical chlorinated hydrocarbon contaminated sites [PDF]
Accurate assessment of the pollution flux and its uncertainty in the plume boundary of NAPL dissolved phase pollution in organic contaminated sites is very important for site risk assessment and decision management.
Hongyu YAO +4 more
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野生动物学报, 2020 以上海动物园人工哺育的11只幼獐（雄性3，雌性8）为研究对象，收集1—15周龄的体重（Y）、体长（X2）、前后足长（X5，X4）、肩高（X1）、胸围（X3）、耳长（X6）和尾长（X7）8项体尺数据。利用SPSS 18.0计算各体尺的平均值，对所选8项体尺进行相关性分析，建立幼獐的体重增长模型，并对影响体重较大的几项体尺构建回归方程。采用经典动物增长非线性Logistic、Gompertz、von Bertalanffy函数模型和Gauss、幂函数、指数函数对人工哺育幼獐体重生长曲线进行拟合 ...
耿广耀, 刘群秀, 袁耀华
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Feasibility study on contact stiffness acquisition by hammering tests and numerical back-analysis for parallel structural plane of rock mass [PDF]
, 2016 针对相对均匀的平行结构面,基于结构面的线性接触假设,提出了一种利用锤击试验及数值反演获得结构面接触刚度的方法。该方法实施时,在结构面两侧分别布设若干支振动传感器,在远处利用激震锤进行激震,通过结构面两侧垂直于结构面方向和平行于结构面方向振动传感器的起跳时间,计算出纵波和横波通过结构面的耗时,而后利用数值计算进行反分析,通过不断调整结构面的法向和切向接触刚度,实现与现场实测相同的耗时,从而获得该结构面的法向和切向接触刚度特性。对该测试方法的可行性进行了理论、数值方面的论证 ...
乔继延 +4 more
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Simulated test of gas loss calculation during the freezing coring process inunderground coal seam [PDF]
The freezing coring technology can not only perform the fixed-point sampling in coal seams, but also effectively reduce gas leakage during the sampling process.
Jun LIU +5 more
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The System Simulation of China's Grain,Fresh Water and Energy Demand in the Next 30 Years [PDF]
, 2010 本文以系统动力学为主要方法,对未来我国的人口总量和经济水平进行了预测,在此基础上对未来粮食、淡水和能源的需求规模进行了仿真,提炼出人口、经济与粮食、淡水和能源需求的关联模式,并进行了灵敏度分析,探讨了为确保粮食、水、能源安全所能采取的有效措施。This paper forecasts chinese population by disintegrate research and economic level in the future;simulates the demand scale of ...
周伟, 米红
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