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931.
常见的网络定位技术主要有GNSS定位、基站定位、WiFi定位三种,每种定位技术都有其应用的场景和优缺点。现有的定位性能评估方法因涉及较专业的实验室设备,存在设备采购和维护成本高、场景覆盖较少等问题。本文提出了一种基于多用户协同的网络定位性能评估方法,该方法通过多用户手机协同机制采集大量高精度的GNSS基准位置评估基站或WiFi等粗精度网络定位性能,文章分析了该方法的实现流程,并通过试验场景和数据分析对比,最终给出了评价。  相似文献   
932.
该文介绍了国内管路清理现状,分析目前国内管路清理方法的优缺点,推出一种新型管路清理方法——管路清理器。该方法采用特制的清理器,具有易操作、无污染等特点,在煤矿排水系统应用中取得良好的效果。  相似文献   
933.
Imaging with high definition video camera is an important technique to visualize the drilling conditions and to study the physics of complex multiphase flow associated with the hole cleaning process. The main advantage of visualizing multiphase flow in a drilling annulus is that the viewer can easily distinguish fluid phases, flow patterns and thicknesses of cutting beds. In this paper the hole cleaning process which involves the transportation of cuttings through a horizontal annulus was studied. The two-phase (solid-liquid) and the three-phase (solid-liquid-gas) flow conditions involved in this kind of annular transportation were experimentally simulated and images were taken using a high definition camera. Analyzing the captured images, a number of important parameters like velocities of different phases, heights of solid beds and sizes of gas bubbles were determined. Two different techniques based on an image analysis software and MATLAB coding were used for the determinations. The results were compared to validate the image analyzing methodology. The visualization technique developed in this paper has a direct application in investigating the critical conditions required for efficient hole cleaning as well as in optimizing the mud program during both planning and operational phases of drilling. Particularly, it would be useful in predicting the cuttings transport performance, estimating solid bed height, gas bubble size, and mean velocities of bubbles/particles.  相似文献   
934.
The article discusses future trends and their implications on separation technologies starting from the main drivers of technological developments. Especially the consequences of the expected energy and raw material change and the increasing international economic competition on process technologies are addressed. Special attention is given to the opportunities of increasing computational power and the availability of high-performance networks for scientific modeling and their use in process industries.  相似文献   
935.
田瑞生 《四川建材》2020,(4):142-143
本文结合笔者工程经验,提出了采用工厂化清洗高速公路防眩设施(防眩板)的机制,以求采用标准化的形式对防眩板进行清洗和养护工作,并综合分析了采用工厂化清洗高速公路防眩设施(防眩板)的优点,为行业发展献言献策。  相似文献   
936.
5G移动通信技术的发展,为无人驾驶汽车的高速反应、安全驾驶提供了更多的技术可能,无人驾驶汽车的关键技术包括导航定位、环境感知、路径规划、稳定牵引控制、防抱死制动和自动泊车技术,以上关键技术的实现,还需传感器、GPS和北斗卫星导航系统、RFID无线射频技术等信息技术的支持.无人驾驶汽车的高速发展使得其可以更快地投入现实使用,解决人们的日常生产、生活问题,保障人们的生命财产安全.  相似文献   
937.
The handling of single cells is of great importance in applications such as cell line development or single-cell analysis, e.g., for cancer research or for emerging diagnostic methods. This review provides an overview of technologies that are currently used or in development to isolate single cells for subsequent single-cell analysis. Data from a dedicated online market survey conducted to identify the most relevant technologies, presented here for the first time, shows that FACS (fluorescence activated cell sorting) respectively Flow cytometry (33% usage), laser microdissection (17%), manual cell picking (17%), random seeding/dilution (15%), and microfluidics/lab-on-a-chip devices (12%) are currently the most frequently used technologies. These most prominent technologies are described in detail and key performance factors are discussed. The survey data indicates a further increasing interest in single-cell isolation tools for the coming years. Additionally, a worldwide patent search was performed to screen for emerging technologies that might become relevant in the future. In total 179 patents were found, out of which 25 were evaluated by screening the title and abstract to be relevant to the field.  相似文献   
938.
The aim of this contribution is to analyze the challenges for technology diffusion policies to achieve expected socio-economic goals and to deduce conclusions for an adequate policy design. Based on hypotheses from theoretical contributions, we review two rather distinct technology fields. One is biobased products, the other health technologies with bioethanol and magnetic resonance imaging respectively as case studies in order to derive rather general insights regarding those policies. The case studies highlight the difficulties in achieving the aimed societal goals by promoting technology diffusion. The dominant innovation design (e.g. techniques or resources used) which diffuses or its application fields (e.g. indication, patient characteristics) differ from those assumed in impact assessments and side-effects which occur in other markets. The direct linkage of policy measures to societal criteria may avoid some of those undesired developments but may have side effects of their own, such as trade distortions or shifting the environmental burden to other activities. However, there is considerable scope for improvement in policy design compared to the status-quo. Overall, a more balanced policy mix regarding various socio-economic goals is vital and unintended side effects have to be considered more in decision making.  相似文献   
939.
Improvement of the microbial fuel cell performance is highly required in energy production associated with domestic sewage treatment. For this objective, metal electrodes coated with specific materials for anode and cathode were manufactured. Materials such as reduced graphene oxide (rGO) as an anode, with high electrical conductivity, and structured nickel oxide (sNiO), which act as air cathode, could be the key to obtaining substantial improvements in the production of energy and treatment of domestic sewage. In this work, simple methods were developed to coat the stainless steel meshes with rGO and sNiO, used in MFC prototypes. The results show that the methodologies developed for the coating of the electrodes aid to improve the performance of the MFC in the delivery of potential, current density and power density up to 220%, 140% and 700% respectively, compared to the blank stainless steel electrodes; while the COD levels in the water purified by the MFC with covered electrodes reached a decrease of 36% compared to the same system without covered electrodes. Additionally, the built MFCs prototypes were tested as a power supply for a digital clock and an LED light.  相似文献   
940.
解冻是肉类加工或烹饪前的重要步骤,不恰当的解冻工艺会导致肉类品质的劣变,因此,开发高效益的解冻工艺是十分必要的。解冻工艺的发展在经历了传统工艺、新型工艺后,近年又涌现了一些独特且具有创新性的解冻工艺。本文除简要概括肉品解冻过程及常见解冻工艺之外,综述这些独特的解冻工艺,介绍其开发思路、解冻原理和相关研究内容,并对未来解冻工艺的发展提出建议,旨在为肉及肉制品解冻工艺的选择和优化提供参考。  相似文献   
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