時變梯度 的英文怎麼說
中文拼音 [shíbiàntīdù]
時變梯度
英文
time varying gradient-
There is a period of soil contents range from ten to twenty five days over the humid discussed area in summer, and the period is not obvious at the discussed zone of close oasis desert area in summer and winter. ( 2 ) soil temperature exits several periodic variations of different depths ranging from six to twenty four days in heihe region, and nine to thirty days in gaize and shiquanhe region. it also shows that gradient of soil temperature affects on the soil content movement more greatly in summer. ( 3 ) the land surface temperature of yangtze river lower region is retrieved from noaa - ahvrr data
( 2 )根據土壤溫濕資料,採用功率譜分析、 pca分析等方法,分析了兩種典型下墊面土壤溫度的時空分佈特徵及其對土壤水分運動的影響,發現研究區土壤溫度除日和年變化周期外還存在6 30天的不同周期;下墊面的非均勻性及其季節變化及溫度梯度變化對土壤水分運動有很大影響,冬季溫度梯度變化對土壤含水量影響大於夏季溫度梯度對上壤含水量變化的影響,且溫度梯度與水分運動方向相反。For this reason, to analyze the spatial and temporal dynamic of ground water table and water quality beneath the typical phytocommunity in particular areas, will be helpful to probe into the dynamic formation of soil moisture and salinity, and to understand the spatial variation of vegetation
因此,分析區域內典型植物群落的地下水水位、水質在時空上的動態變化,有助於探討土壤水鹽動態變化的形成條件,揭示植被在空間上梯度變化的原因。In order to fully refect the geo - tech basic mechanics behaviors and to rationally explain the strain localization, this paper establishes the theory framework of gradient - dependent plastic model based on the theory framework of gradient - dependent plastic mechanics and in considering the plastic strain ' s gradient - dependence in double yield function, offers a kind of possible concrete pattern of the generalized plastic gradient model and analyzes each parameter of the model, particularly with the physical sense of " localized parameters " and the elements producing possible effect upon the model
為了較全面地反映巖土的基本力學性質,同時合理解釋應變局部化現象,本文基於廣義塑性力學的理論框架,在雙重屈服函數中考慮了塑性應變的梯度依賴,建立了廣義塑性梯度模型的理論框架,並給出了廣義塑性梯度模型的一種可能的具體形式,分析了該模型的各個模型參數,尤其是其中的「局部化參數」的物理意義和可能對其產生影響的因素。Identification of forgetting drifting time - varying systems
基於梯度的擾動時變系統辨識演算法及其收斂性When the rf pulse is combined with magnetic field gradients, a spatially encoded signal is produced that can be detected and translated into images
當射頻脈沖與磁場梯度聯合起來時,我們可以探測到一個空間編碼信號的產生並且將它轉變成圖像。Compared with the classical bp algorithm, robust adaptive bp algorithm possesses some advantages as following : ( 1 ) increasing the accuracy of the network training by means of using both the relative and absolute residual to adjust the weight values ; ( 2 ) improve the robustness and the network convergence rate through combining with the robust statistic technique by way of judging the values of the samples " relative residual to establish the energy function so that can suppress the effect on network training because of the samples with high noise disturbances ; ( 3 ) prevent entrapping into the local minima area and obtain the global optimal result owing to setting the learning rate to be the function of the errors and the error gradients when network is trained. the learning rate of the weights update change with the error values of the network adaptively so that can easily get rid of the disadvantage of the classical bp algorithm that is liable to entrap into the local minima areas
與基本bp演算法相比,本文提出的魯棒自適應bp演算法具有以下優點: ( 1 )與魯棒統計技術相結合,通過訓練樣本相對偏差的大小,確定不同訓練樣本對能量函數的貢獻,來抑制含高噪聲干擾樣本對網路訓練的不良影響,從而增強訓練的魯棒性,提高網路訓練的收斂速度; ( 2 )採用相對偏差和絕對偏差兩種偏差形式對權值進行調整,提高了網路的訓練精度; ( 3 )在採用梯度下降演算法對權值進行調整的基礎上,通過將學習速率設為訓練誤差及誤差梯度的特殊函數,使學習速率依賴于網路訓練時誤差瞬時的變化而自適應的改變,從而可以克服基本bp演算法容易陷入局部極小區域的弊端,使訓練過程能夠很快的「跳出」局部極小區域而達到全局最優。In the summer stratified water column, the deeper the maximum depth of food distribution is, the stronger the dvm is performed ; the increase of the gradient of temperature in the thermocline layer can decrease the magnitude of the dvm and form the thermal barricade to the copepod ; the effects of the predation pressure on dvm is complex. on the one hand, the variations in the distribution depth of the predation pressure vs. the thermocline layer or the depth of the maximum food can modify the dvm patterns of the copepod. on the other hand, different predation pressure induces different dvm patterns
在夏季分層水體中,食物的最大分佈深度越大,動物向下遷移的幅度也越大;溫躍層的溫度梯度增大可以減小動物遷移的幅度,成為橈足類垂直遷移的溫度屏障;捕食壓力對垂直遷移的影響較復雜,一方面,捕食壓力的分佈深度與溫躍層或食物峰值的相對位置的變化能夠改變橈足類垂直遷移的模式,另一方面,捕食壓力強度不同,橈足類垂直遷移的幅度也不同,捕食壓力越大,遷移的幅度越大,當捕食壓力增加到一定程度,橈足類停止向上的遷移,大部分時間呆在水體深層,可能進入捕食壓力引起的「滯育」狀態。In this thesis, some key issues of the vr technique are systematically investigated. firstly, for the image filters and image interpolation between slices, a integrated interpolation algorithm is presented based on the contour shape and correspondence matching, which keeps the shapes and grays information the objects of interest. secondly, the fidelity of effect of the vr for medical images is studied, and a continuous - gradient - based method for transparent volume rendering is proposed, which vivifies the results of volume rendering
首先,研究了醫學斷層圖像數據的濾波及層間插值技術,提出了一種基於輪廓形變和對應點匹配相結合的混合插值演算法,在實現圖像層間插值的同時保持了目標的輪廓形狀與灰度信息;其次,對醫學影像容積重建效果的逼真度進行了研究,提出了一種基於連續梯度轉換函數的互動式透明體繪制方法,使重建效果更加生動、真實。Through the thermodynamic analysis for the sandstorm weather according to the simulated potential temperature, potential vorticity field, it is found that this sandstorm weather occurred in the condition of the atmospheric stratification stability, the area of the high potential temperature value and the potential temperature gradient have a good corresponding relationship with the surface cold air and cold front, so are the strength of potential vorticity and the different developing stage of sandstorm
利用輸出的位溫、位勢渦度場,對沙塵暴天氣進行熱動力條件分析,發現本次沙塵暴天氣發生在大氣層結穩定狀態下,位溫大值區及位溫梯度與地面暖低壓的強弱和移動有著很好的對應關系,位渦的水平分佈特徵和強弱變化對沙塵暴的出現時間和落區有一定的指示意義。Optimal periodic control with the lowest operational cost by limiting total substrate discharge mass was studied. through adding new state variable and using supplement functions, the problem with restriction conditions was converted into nonrestriction problem. in addition, the dynamic searching method of optimal step coefficient was developed to modify the conventional gradient method, consequently the calculation problem of the multivariable optimal periodic control was able to be resolved better. it was found that the operational costs of optimal control under various initial states are distinctly different. a new concept of optimal control under optimal initial state was presented. it is pointed out emphatically that to the treatment system without optimal control condition, the suboptimal control with extensive practical value can be realized according to the results of optima control
著重研究了在限制有機物排放總量時,使其運行費用最低的最優周期控制問題.通過增加新的狀態變量和用補償函數法,將本課題的有約束條件問題化為無約束條件問題,並提出了最優步長參數的動態搜索法來修改傳統的梯度法,從而較完善地解決了多變量最優周期控制的計算問題.研究中還發現了不同初始條件下最優控制所需要的運行費用也大不相同,進而提出了最優初始狀態下最優周期控制的新概念,這對保證出水質量的同時進一步降低污水處理成本來說具有更重要的意義.本文還強調指出:對于尚不具備實現最優控制條件的處理系統,可根據最優控制的研究結果實現具有廣泛實用價值的準最優控制We analyzed the alternative in functional phenotypic plasticity responding to variational entironments, consequently, we interpreted the difference between endangerment and wide - distribution of these closely related species, and the results showed : 1 all of the daily changes of photosynthetic rate responding to different water status show " double apices " except m. d, the daily changes of photosynthetic rate in m. d shows " simple apices " responding to arid soil water content, while " double apices " responding to the other soil water content. emerging time of daily maxim of pn is difference between species and between treatments. daily course of transpiration and stomatal conductance of these for species all show " double apices ", but the emerging time of daily maxim of transpiration rate and stomatal conductance rate are all different between species
結果表明: 1 、除小魚仙草外,四物種的光合速率日變化在不同水分梯度下均表現出「雙峰型」 ,小魚仙草的光合速率日變化在於旱時表現出「單峰型」 ,其餘水分梯度下表現出「雙峰型」 ,種間和梯度間日最大光合速率出現時間有一定的差異;四物種蒸騰速率和氣孔傳導力日進程也表現出「雙峰型」 ,但種間日最大氣孔傳導力和蒸騰速率出現的時間也存在一定的差異。The improvement on conditioning and aeration of double fluids system by atomizing and controlling the air humidity was fully introduced in this paper, as well as solved the shortcomings of high moisture grades between the mirage soaked wind - pipeline and the surface of the grain, and between the superstratum and substrate after conditioning by a serios of managing measures, such as changing the way of ventilation, adjusting the aeration time by controlling the air - humidity of ventilation
摘要詳細論述了雙流體調質通風系統在水汽霧化、空氣濕度控制方面的改進,包括改變送風方式、調整干濕空氣通風時間等管理措施,較好地解決了調質過程中的水霧浸濕風道與糧面、糧堆上下層水分梯度大等的儲糧問題。Based on this, the upper controlling index of soil water content is 80. 4 % and the days of waterlogged and salinization tolerance is 3. 2 days. the moisture and salinization movement mathematical model in the field under subdrainage condition is based on the assumption of neglecting the effects of horizontal hydraulic gradient, it can analogy the changes of soil water content and salinization which are changed with times and depth
論文在忽略水平方向水力梯度影響的假定下建立了排水條件下麥田水鹽運移模型,模擬土壤水鹽含量隨時間、空間的變化情況。經與實測資料對比發現,計算值與實測值較為接近,故該模型及參數的確定是合理的,可用於預測麥田水鹽的動態變化。The paper studied three aspects of extracelluar enzymes in sediments of the tidal flat wetland, namely 1 ) the distibution of five sorts of extracellular enzymes in sediments in the east end of chongming island along the elevation gradient or community succession series, the relationships between the activities of enzymes and the ecological factors, and functions of extracellular enzymes in the process of community succession ; 2 ) the effects of the heavy metal ions and edta on the activity of alkaline phosphatase in sediments of the east end of chongming island by adding and removing of heavy metal ions, discussing whether the activities of extracellular enzymes could be taken as the indicators for the environmental status ; 3 ) the variations of the activities of extracellular enzymes in sediments in the east end of hengsha island after the discarding clay
本文以長江口典型濕地?崇明東灘為例,首次研究了沿高程梯度或沿植被演替系列沉積物中堿性磷酸酶等五種胞外酶活性的空間分佈規律,分析了胞外酶活性與環境因子的相互關系及其產生機制,討論了胞外酶活性在濕地植被演替中的作用。同時以崇明東灘沉積物為對象,運用重金屬離子的添加和去除等方法,研究了重金屬離子對沉積物中堿性磷酸酶活性的影響,利用胞外酶活性的變化探討了崇明東灘重金屬污染的狀況。此外,本文還研究了橫沙東灘吹泥試驗工程對沉積物環境因子和胞外酶活性的影響並進行了對比分析。We discussed the main characteristic parameters of seismic kinesiology and dynamics of mine engineering fracture zone, including relative amplitude, phase time of wave crest, similarity factor, principal frequency band energy, 3 - d space time gradient and coherent coefficient et al., and puts forward the processing method of 3 - d seismic characteristic parameters about denoise - smoothing, generalization, correlation analysis, characteristic transformation ; and presents the method of pattern recognition of mine engineering fracture zone
摘要本文從時間域、頻率域、三維空間域介紹了礦山工程裂隙破碎帶主要的地震運動學、動力學屬性參數,包括相對振幅、波峰相位時間、相似系數、主頻帶能量、二維空間時間梯度和相干系數等,提出了礦山工程裂隙破碎帶三維地震屬性的去噪平滑、歸一化、相關分析、特徵變換的處理方法以及裂隙破碎帶的模式識別原理與方法,並用實例說明了該方法的應用效果。In this application, the lorentz force generated by the interaction between the current in the wire and the geomagnetic field produces an electro - dynamic drag leading to a fast orbital decay. in this paper, we make an intensive study of the process of de - orbiting using electro - dynamic tether system. the concrete work includes : firstly, i have studied the basic principle of how to generate the electro - dynamic drag, modeled via accuracy geomagnetism, made a concrete analysis of the de - orbiting duration, the magnitude and direction of electro - dynamic drag under the action of the dipole and accurate geomagnetic models, set up a counterbalance between electro - dynamic torque and gravity gradient torque, emulate the de - orbiting process of spacecraft, and compared the change of six orbital factors and the de - orbiting duration under the action of the dipole and accurate geomagnetic models
本文對基於電動力纜繩的航天器離軌過程進行了深入研究,具體工作如下:首先,本文研究了電動力纜繩產生電動力拉力的基本原理,建立了精確地磁場模型;分別在偶極子模型和精確地磁場模型作用下,對電動力拉力的大小、方向、離軌時間及電動力纜繩傾角的大小進行了計算分析;建立了電動力力矩與纜繩系統重力梯度力矩的平衡關系;分析了電動力力矩為系統提供能量的原理;最後分別在偶極子地磁場模型和精確地磁場模型作用下,對受電動力纜繩作用的航天器的離軌過程進行模擬,分析了在不同精度地磁場模型下,航天器離軌過程中各軌道參數的變化情況,並比較了不同模型對離軌時間的影響。( 2 ) on the basis of continuity equation, momentum conservation equation, energy conservation equation, and substantial equation, coupled thm governing equations are derivated with giving up the assumption of local thermal equilibrium, adopting thermal elasto - plastic constitutive relation, taking the effect of temperature gradient on groundwater seepage ( analogous to soret diffusion ) and the effect of viscous dissipation of groundwater on temperature field of rock mass into account
( 2 )根據連續性方程、線動量平衡方程和能量守恆方程以及相應的物性方程推導了飽和巖體溫度場-滲流場-變形場三場耦合作用控制方程組。在推導控制方程組時舍棄了「局部熱平衡」假設,採用了熱彈塑性本構關系,考慮了溫度梯度對地下水滲流的影響(類soret效應)以及地下水的粘性耗散對巖體溫度場的影響。Adaptive grid techniques through a variational approach are applied to two shock problems with exact solutions. more grid points are redistributed in the shock regions in response to numerical solution and thus the shock can be captured successfully. the results show the techniques have excellent qualities in improving accuracy of numerical solution and reducing cpu time
利用變分原理的自適應網格技術被應用到兩個有解析解的激波問題上,它能根據問題的求解,在解的大梯度區自動加密網格,從而非常成功地算出了激波。通過分析發現自適應網格技術在提高精度減少運行時間方面顯示了優良的性能。Convergence of forgetting gradient estimation algorithm for time - varying parameters
時變參數遺忘梯度估計演算法的收斂性When flier - plate with graded wave impedance impacted targets with different thickness at different velocities, the variation of the impact - induced wave profiles accorded with the numerical simulation results
梯度飛片以不同速度撞擊不同厚度的靶板時,所得到的準等熵壓縮波波形的變化規律符合數值模擬計算的結果。分享友人