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31.
32.
介绍了用废旧纯铝料,在特殊的固体燃料反射炉中连续熔化,水平连铸成(3.0~9.5)mm铝线坯的工艺流程及设备。经过试验,确定是一种生产炼钢脱氧用铝线的经济、有效的工艺方法。 相似文献
33.
Tao LiuAuthor Vitae Boxiong WangAuthor Vitae 《Sensors and actuators. A, Physical》2011,171(2):186-190
Intersection technology plays a key role in long-distance horizontal directional drilling (HDD). Magnetic ranging technology is an effective way to realize the intersection. A three-dimensional magnetic field model suitable for the cylindrical magnet connected with drilling bit was established. New formulae of magnetic induction intensity were deduced from the fundamental formulae to suit to the new magnetic ranging method. Based on the new formulae, a curve fitting model was established to complete the ranging. The whole process is simple and effective. The result of the experiment proved the feasibility of the new method and the accuracy is high enough for HDD. 相似文献
34.
Internet of Things (IoT), one of the key research topics in recent years, together with concepts from Fog Computing, brings rapid advancements in Smart City, Monitoring Systems, industrial control, transportation and other fields. These applications require a reconfigurable sensor architecture that can span multiple scenarios, devices and use cases that allow storage, networking and computational resources to be efficiently used on the edge of the network. There are a number of platforms and gateway architectures that have been proposed to manage these components and enable application deployment. These approaches lack horizontal integration between multiple providers as well as higher order functionalities like load balancing and clustering. This is partly due to the strongly coupled nature of the deployed applications, a lack of abstraction of device communication layers as well as a lock-in for communication protocols. This limitation is a major obstacle for the development of a protocol agnostic application environment that allows for single application to be migrated and to work with multiple peripheral devices with varying protocols from different local gateways. This research looks at existing platforms and their shortcomings as well as proposes a messaging based modular gateway platform that enables clustering of gateways and the abstraction of peripheral communication protocol details. These novelties allow applications to send and receive messages regardless of their deployment location and destination device protocol, creating a more uniform development environment. Furthermore, it results in a more streamlined application development and testing while providing more efficient use of the gateway’s resources. Our evaluation of a prototype for the system shows the need for the migration of resources and the QoS advantages of such a system. The examined use case scenarios show that clustering proves to be an advantage in certain use cases as well as presenting the deployment of a larger testing and control environment through the platform. 相似文献
35.
人脸特征的定位是计算机人脸识别中必需的一步。该文提出了一种在彩色图象中进行人脸部特征定位的新方法。该方法只取彩色图象中的红色成分作为研究对象,以简化处理及提高信噪比;首先利用对原图的垂直灰度投影曲线确定脸的左右边界,并分离出此区域的高低灰度图,以便分图定位脸部特征;接着利用对经边缘检测的高灰度图的水平灰度投影确定下颌,嘴,鼻,眼的垂直位置,然后在相应位置附近,对鼻,眼、嘴依此进行准确定位,算法最后 相似文献
36.
水平井开采地下水方案优选的实例研究 总被引:1,自引:0,他引:1
为了合理有效地开采地下水,科学地设计地下水开采方案非常关键。在陕西省北部神木县境内的合河水源地选择了廊道、辐射井和渗流井3种水平井开采地下水方式,每种方式设计了多种开采方案,其中廊道有20种方案,辐射井有2种,渗流井有2种。利用Visual MODFLOW软件,以"等效渗透系数"及"渗流-管流耦合模型"为理论基础,对不同方案进行地下水流数值模拟,并分别计算其平水期和枯水期的取水量。考虑枯水期的衰减程度、施工难度、造价及管理的难易程度等多种因素,最终确定"4眼渗流井开采"为最佳方案,其平水期总开采量为35 400m3/d,枯水期总开采量为27 500m3/d。 相似文献
37.
《Ergonomics》2012,55(9):1859-1866
The objective of the present laboratory study was to analyse physiological responses of horizontal lifting tasks when they were performed in sitting and standing positions. Heart rate and blood pressure were used as indices of circulatory strain. Lifting tasks were performed under four lifting positions: sitting-forward lift, sitting-twist lift, standing-forward lift, and standing-twist lift. The weights of the loads were 3, 5 and 7 kg and the frequencies of handling were 1, 4 and 6 lifts/min. This study supports the idea that heart rate is a sensitive measure for evaluating the effects of seated horizontal lifting tasks. The lifting positions and workload (frequency × load × distance) are important parameters in the design of these types of tasks. It appears that within the experimental values examined in this study, a seated position could be recommended while performing horizontal lifting tasks at workloads ≤4·6 kg.m.min ?1;. The results are supported by smaller physiological responses. 相似文献
38.
在页岩气的开发中,为了获得更高产能,超长水平井的应用成为必然。超长水平井的垂深计算受地层倾角影响较大,计算垂深时必须考虑地层倾角的影响。当井斜大于90°时,常规垂深计算方法会出现数据丢失现象,对地层对比造成困扰。通过建立校正模型,根据地层倾角分别对井斜及大于90°的井斜进行校正,再根据校正后的数据计算垂深,可较好的消除地层倾角的影响及当井斜大于90°时的数据丢失现象,保证了水平井眼轨迹计算分析的正确性,也为后期压裂改造提供支持。 相似文献
39.
水平井是老油田开发后期挖潜剩余油的重要技术手段,但部分水平井经过一段时间的生产后,产能大幅下降且措施调整难度大,效果不明显。针对常规措施无效的水平井,二次射孔作业往往能收到较好的增产效果。 相似文献
40.
片内多核已成为延长摩尔定律的方式,并行算法设计、编程模型、编译器和运行时系统都需要利用计算模型进行分析。现有多核模型对线程间共享缓存等资源的竞争已有较精确的模型,但是对于线程间数据共享考虑较少。提出线程间共享缓存的横向局部性和任务共享率概念,基于此扩展串行存储层次模型RAM(h),提出考虑任务共享率的多核并行计算模型MRAM(h)。 相似文献