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91.
Seepage well is an emerging Low Impact Development (LID) technology that can effectively control the storm runoff. However, its rainwater infiltration rate and storage capacity still require further enhancement. By setting a horizontal infiltration structure at the bottom of conventional rainwater seepage well (CSW), an enhanced seepage well (ESW) was proposed in this study, and its infiltration performances compared with the permeable pavement (PP) and the CSW were systemically investigated using static infiltration experiment and HYDRUS-2D simulation. The results showed that the infiltration efficiency of ESW was significantly higher than that of PP and CSW, and the process of water infiltrated through soil mainly controlled the macroscopic infiltration rate. The Nash-Sutcliff Efficient (NSE) index was used to evaluate the accuracy and reliability of the HYDRUS-2D model, and the results of NSE values greater than 0.75 (varied between 0.75 and 0.91) confirmed the applicability of HYDRUS-2D to describe correctly the hydraulic behavior of the ESW system. Simulation infiltration tests showed that the ESW performed a higher average infiltration rate and fewer total runoff volume than the CSW, indicating the effectively enhancement of the infiltration and water retention capacity of ESW, especially under heavy rainfall intensities. Additionally, the ESW system exhibited an excellent runoff-control and rainwater retention capacity in an actual rainfall scenario. 相似文献
92.
赵丽丽 《水资源开发与管理》2021,(3):34-37
本文在分析阎王鼻子水库建设前后下游水文情势变化的基础上,根据河道内生态不同需求和不同计算方法,确定水库下游河道基本生态流量和目标生态流量两种需求方案。在充分考虑大凌河流域河道外需水的前提下,研究分析了阎王鼻子水库最大程度满足河道内不同生态需水要求时的调度方案,对改善水库下游河道环境具有一定的指导意义。 相似文献
93.
姜文超 《水资源开发与管理》2021,(1)
本文以东汶河城区段生态修复工程为例,结合城市河道治理对该地区的湿地水生态修复工程进行了设计,采用雨污分流、河底清淤,软质河底、地形泡、滚水堰以及河心岛的构建方法,达到了控制水位、控制流速、促进微生物和植物生长的目的,改善了湿地水质较差的问题,完善了湿地生物系统,丰富了食物链层级,解决了湿地生态系统的良性循环问题。可为类似生态修复工程提供参考。 相似文献
94.
T. R. Guilinger M. J. Kelly J. R. Scully T. M. Christensen D. Ingersoll J. A. Knapp R. I. Ewing W. H. Casey S. S. Tsao 《Journal of Fusion Energy》1990,9(3):299-304
We describe several electrochemical methods used to investigate the possibility of cold fusion phenomena in palladium and titanium tritide cathodes. We performed long-term (up to 77 days) electrolysis experiments with electrochemical cells of the University of Utah type at current densities as high as 1 A/cm2, while monitoring neutron and tritium levels. With some cells, we pulsed the current to determine if neutron bursts would result. In another cell, we used titanium tritide as the cathode to determine if D-T reactions yielding neutrons would occur. In no instance were levels of neutrons or tritium significantly above background except in the titanium tritide cell where isotopic exchange, occcurring between the electrode and the electrolyte, resulted in significant tritium levels. We also combined x-ray photoelectron spectroscopy (XPS) and electrochemical hydrogen permeation experiments to determine the effectiveness of various Pd surface treatment procedures on the resultant electrochemical hydrogen absorption efficiency. Electroanalytical and thermal desorption/gas analysis techniques indicated the maximum loading of H in Pd was to a ratio of HPd=0.8. 相似文献
95.
One of the symptoms of plagues, epidemics or pandemics is often a fever, so during such unprecedented times, handheld infrared thermometers are vital devices for monitoring symptomatic individuals. It is therefore very important to enhance reading efficiency when these thermometers are used for lengthy periods of time in a low illuminance environment. The need for the efficient reading of infrared thermometers or a fast reaction time when reading the information is even more relevant now during the COVID-19 pandemic. In this study, a target search experiment of digital characters is carried out through a simulated interface and use scenarios of a handheld thermometer based on three variables: the inclination angle or slant of the seven segment display characters, screen brightness, and ambient illuminance. The experimental results show that the inclination angle or slant of the characters and ambient illuminance have a significant effect on the reaction speed. In general, the slowest reaction time is found when reading characters with a slant of 10° to the left and the reaction time is the fastest with a right slant of 20°. A continued reduction in ambient illuminance does not affect the visual recognition performance but instead further enhances reading efficiency. Increasing the screen brightness increases the reaction time more in relatively low ambient illuminance conditions as opposed to relatively high ambient illuminance, which implies that in higher ambient illuminance conditions, a brighter screen needs to be used to obtain the same reaction speed as that in lower ambient illuminance conditions. 相似文献
96.
An inductively coupled (ic) radio-frequency (rf) stabilized argon plasma was generated in a quartz tube using a 7 MHzrf generator. The electrical and thermal powers were measured and the efficiency of energy conversion was computed. The results
indicate that for a constant power input, there is an optimum argon flow rate for which maximum energy conversion efficiency
occurs. 相似文献
97.
98.
在车联网中,由于部分路侧单元(RSU)的位置比较偏远,无法得到网络管理员的及时维护,可能遭到攻击,变为不可信任的路侧单元,降低了车辆的通信质量和网络能效.为了有效地识别RSU的可靠性,提出了一种基于信任度的路侧单元识别及资源分配算法,将路侧单元识别、传输模式的选择和功率分配联合建模为网络能效的优化问题,并分成3个子优化问题,分别求解.首先,采用基于信任度的RSU识别算法,识别出可信任和不可信任的路侧单元;其次,优化车辆资源块配置和链路选择;最后,通过次梯度算法优化传输功率,最大化网络能效.理论分析和仿真结果表明,所提算法具备较低的复杂度,可以达到较高的路侧单元识别准确度,并有效地提升网络总能效. 相似文献
99.
针对应用于重整制氢微反应器的复杂多孔金属纤维载体(PFS)的流速场高效分析难题,建立载体中随机微通道的等效电阻网络分析模型. 基于复杂随机纤维结构的统计网络模型,将纤维载体中三维联通的随机微通道结构及与之相连的进出口腔简化为规则的网络通道结构.借鉴基尔霍夫定律,建立纤维载体的等效电阻网络模型,并确定求解方法. 纤维载体流速场实例分析的结果表明,基于等效电阻网络模型求解的纤维载体流速场与计算流体力学(CFD)方法的结果之间的皮尔森相关系数约为98%,且求解效率约为CFD方法的2.9×104倍. 研究成果为多孔纤维型重整制氢微反应器的设计制造提供了新的支撑方案. 相似文献
100.
为了提高振荡水翼的水动力性能和能量捕获效率,基于传统简谐运动模型提出改进运动模型,通过引入俯仰运动系数k,推导改进后俯仰运动规律的一般形式,利用Fluent软件建立水翼的二维模型,综合分析半主动振荡模型下不同俯仰运动系数、折算频率和俯仰振幅等运动参数对水翼能量捕获性能的影响。结果表明:与传统简谐运动模型相比,改进运动模型能够使水翼升力系数在较长时间段内维持较大数值,提高水翼的升力系数和捕能效率;在相同的折算频率和俯仰振幅下,减小俯仰运动系数会增大俯仰角转动的角速度,进而增大俯仰运动所消耗的能量;不同俯仰振幅下对应不同的最优折算频率,折算频率越低水翼的捕能性能越不稳定,俯仰振幅越大,转动俯仰角所消耗的能量越多。在给定参数条件下,水翼的能量转化效率可超过40%。 相似文献