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1.
郝建奇  孙强 《河南科学》2014,(3):421-424
结合坡体的地形地貌、水文地质条件、地层岩性特征,进行了不同水位情况下的斜坡稳定性计算.分析了不同蓄水水位对坡体稳定性的影响及其控制因素.  相似文献   
2.
改革开放之后,中国设计业得到了快速发展,设计教育也快速成长起来。通过解读工业设计行业、教育和社会发展的变化,探究设计教育的真谛,科学地进行分类,合理地规划设计教学。根据工业设计学科的特点,实验性地提出一些措施,试图在教学形式上做出改变,以适应新时期设计行业和社会发展的需要。  相似文献   
3.
There is overwhelming evidence that anthropogenic activity has exerted a great influence on climate extremes, especially on heat events at continental to global...  相似文献   
4.
To study the effect of cooperative advertising on the supply chain of deteriorating items, this paper establishes a Stackelberg game model for a two-echelon deteriorating items supply chain composed of one manufacturer and one retailer under a given support program with an exogenous participation rate. The manufacturer as the leader determines the wholesale price and production rate, and the retailer as the follower determines the retail price and advertising strategies. The strategies of the players under the decentralized scenario and the centralized scenario are respectively characterized. Numerical simulations and sensitivity analysis are conducted to gain some managerial insights. It is shown that the pricing, advertising and production strategies are negatively correlated to deteriorating coefficient, and both the profit and the channel efficiency decrease with deteriorating coefficient; The interaction between price, advertising investment and production rate results in a higher retail price of the centralized channel compared to that of the decentralized channel; Implementing the cooperative advertising program does improve the performance of the supply chain in some cases and the participation rate roughly at 0.5 is most preferable, but it is also possible to distort incentive and damage the channel performance when the participation rate reaches a relatively high level.  相似文献   
5.
随着变频技术的不断发展和日趋成熟,其在供热领域的应用也逐渐推广,该技术的应用能够有效地降低电能消耗,对供热企业实际生产运行有着重要的意义。文章介绍了水泵变频节能技术的工作原理、系统特点、实际应用现状及使用效果,同时也提出了实际应用中注意的问题。  相似文献   
6.
针对纤维自动铺放设备中纤维张力控制要求和传统张力控制系统存在的问题,设计了重锤式张力控制系统。该系统将重锤作为张力控制缓冲环节,通过控制重锤位置间接控制张力。系统以运动控制器为控制核心,交流伺服电机为执行元件,激光位移传感器为检测元件。采用模糊PID作为重锤位置控制算法,以充分考虑重锤加速度对纤维张力的影响,避免张力波动。样机实验结果表明:该张力控制系统在有效避免铺放过程中的断线、松弛等问题的同时,其纤维张力的静差率和波动率均能满足工程实际要求。  相似文献   
7.
Inoperable liver tumors are often treated by thermal ablation that destroys the tumor in situ and spares the adjacent hepatic tissue.Thermal–physical treatment has many advantages,but treatment by freezing or heating alone has some limitations.By taking the advantages and disadvantages of cryosurgery and thermotherapy into consideration,a new thermal technique that combines cryosurgery and radio frequency ablation has been proposed,thereby overcoming the disadvantages of each treatment strategy and improving therapeutic outcomes.This new approach remains to be systematically studied in the liver;therefore,this study was performed to estimate survival after alternated cooling and heating ablation therapy in a VX2 rabbit liver tumor model.Sixteen days after VX2 carcinoma implantation into the rabbit liver,tumors were treated with alternated cooling and heating ablation therapy.Rabbits were monitored for 6 months after treatment and assessed with ultrasound(US)and computed tomography at 1,7,14,and 30 days posttreatment.Untreated tumor-bearing animals served as the control group.Our results show that alternate freezing and heating ablation therapy resulted in a good recovery of VX2 rabbits.Compared with the control group,treated rabbits lived significantly longer(P\0.05),with 70%of treated animals surviving to 196 days posttreatment without metastasis or recurrence,while none of the controls did so.There was no local recurrence in the treatment group.All rabbits in the control group developed metastasis,while metastasis was only observed in 30% of treated rabbits.These results suggest that alternate cooling and heating ablation therapy can prolong the survival time of rabbits with VX2 liver tumors and is an effective method for tumor therapy.Furthermore,we also showed in this model that contrast enhanced US is a valid follow-up approach to assess treatment effectiveness.  相似文献   
8.
基于改进方向波变换的泡沫图像增强新方法   总被引:1,自引:0,他引:1  
针对矿物浮选过程中浮选槽内气泡与矿浆背景灰度反差小、光照影响严重且存在大量噪声干扰等问题,提出一种基于改进方向波变换的泡沫图像增强新方法.采用改进方向波变换对浮选泡沫图像进行分解,保证信号产生平移不变性,避免图像边缘模糊;针对分解后低频子带系数值相差甚小,受工业光照影响严重的问题,引入多尺度Retinex算法实现增强效果,改善其亮度均匀性;并对高频部分构造一种双结构元素多尺度形态滤波方法,有效地消除噪声并保持边缘信息.采用工业现场大量泡沫图像进行试验.研究结果表明:所提出的方法可增强泡沫边缘细节,抑制噪声,明显改善泡沫图像的视觉效果,解决泡沫边缘不明显和噪声所带来的图像欠分割问题,有助于泡沫形态特征提取和工况分析.  相似文献   
9.
郝建奇 《科技资讯》2013,(27):97-100
地震资料的去噪,在处理中是非常重要的内容.随着勘探技术的进步,地球物理可以用于去噪的方法越来越多.目前去噪效果相对较好的是小波变换法.小波变化以其独特的时频特性被广泛的使用于地震资料的去噪中.与以前的频率滤波相比,其优越性是可见的.本文简要介绍了小波函数以及用于地震去噪的小波变换的一些方法,并且结合实际来对小波去噪进行了介绍.  相似文献   
10.
Radiation techniques (electron-beam, γ-ray, etc.) are usually used for improving the compatibility between polymer and ingredients in composite materials. Electron-beam pre-irradiation has been used for the first time to enhance the flame retardance of EVA copolymer. Efforts are being made to decline the flammability for EPDM copolymer by EB technique and remarkable reduction has been attained through a series of treatments: pre-irradiation, grafting and saponification.  相似文献   
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