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31.
高山煤矿主采煤层均属高灰、高硫煤,而且矸石易泥化,严重制约煤炭销售。为增强企业产品的市场竞争力,该矿结合矿井实际,采用风选工艺对产品进行加工,有效降低了原煤灰分、硫分,提高煤炭发热量,实现了进一步提高煤质、优化产品结构的目的。 相似文献
32.
随着能源互联网的建设,为了应对配电主站所面临的数据接入和计算压力,文章提出了二级配电网边缘架构,以分布式边缘智能架构缓解主站压力。主要从边缘定义、划分方法、边缘功能描述与交互描述4个方面对所提边缘架构进行介绍。提出电网稳定连接区域概念及其生成方法,并结合南京地区电网实例,说明了以电网稳定连接区域作为边缘划分的合理性。最后,对所提边缘架构在配电网中的实际应用场景进行了设计和展望。 相似文献
33.
Rahul Sasidharan Pillai Matteo Frasnelli Vincenzo M. Sglavo 《Ceramics International》2018,44(2):1328-1333
The present work focuses on the fabrication of βTCP (β-tricalcium phosphate) and HA/βTCP (hydroxyapatite/β-tricalcium phosphate) composite coatings by plasma spraying. The starting powders were produced via solid-state method using 2 wt% MgO to stabilize βTCP phase. The synthesized powders were preliminarily granulated to be used by the plasma spray process. Coatings obtained on titanium substrates are uniform and well adherent but due to the high temperature and cooling rate typical for plasma spraying process, βTCP phase is almost totally transformed into the α allotrope. Thermal treatment at 800 °C allows the reconversion of the phase αTCP→ βTCP. It is therefore possible to produce coatings with tuneable dissolution properties by selecting the proper initial powder mixture and the specific thermal treatment. 相似文献
34.
Biomass combined heat and power (CHP) plants connected to district heating networks are a very good opportunity to increase the share of renewable sources into energy systems. Frequently, important consumers are connected to ensure a stable base heat demand throughout the year but they often have higher requirements in terms of temperature (i.e. steam), which involves a high level of temperature in the district heating network during the whole year and high levels of heat losses in the network. This contribution presents the possibility to decrease the level of temperature at which the district heating network operates and to use high-temperature heat pumps connected locally at the consumption point to produce steam when it is required. An investigation of the global design and integration through thermodynamic simulation models is realised for the University of Liège district heating network. This study is intended to determine the heat pump coefficient of performance and, therefore, to assess the balance between the savings in terms of heat losses and the additional heat pump electricity consumption. 相似文献
35.
景观设计与地域文化元素之间既互相影响又相互作用,在进行设计的时候要将这个地区的文化作为设计的基础,然后在设计的时候两者进行相互融合,这样设计出来的作品才会有更高的文化认同感,而且地域文化也能作为景观设计作者进行创作的源头。 相似文献
36.
Anton Polotai Julie Voak Jim Henry David Thoss Yi Yang Sanjay Chitale 《International Journal of Applied Ceramic Technology》2020,17(2):728-733
The need for electronics to operate at temperatures of 200°C and above continues to grow. These applications include avionics, aerospace, automotive, downhole drilling, mining, and many others. To satisfy this demand, a significant amount of research and development has been conducted. Despite the efforts, the number of new electronic components designed specifically for high-temperature operation is still relatively limited. In Low Temperature Co-fired Ceramic (LTCC) packages, LTCC materials are generally used as the host media for a number of pre-fabricated semiconductor components. As a result, reliability of the entire LTCC package largely depends on the performance of the least robust component. Ferro A6M-E and Ferro L8 are the two well-established and recognized LTCC dielectrics widely used for mid and high frequency LTCC applications, including several high reliability aerospace and defense applications that require demanding Mil-Spec qualifications. This study is our first attempt to characterize and understand basic high-temperature dielectric properties of these two commercial LTCC materials. The secondary objective is to initiate a dialogue in attempt to establish reliability requirements for LTCC packages dedicated for high-temperature operation. 相似文献
37.
针对煤矿发生事故后传统救援监控系统无法实时对井下人员进行动态定位,导致矿井救援盲目性大、救援效率差、救援难度大等技术难题,为了进一步提高煤矿救援效率,通过技术研究,设计了一套以通信基站为核心的智能化救援监控系统,分析了该系统结构组成、工作原理,通过在担水沟煤矿井下实际应用效果来看,智能化救援监控系统对人员定位精准度达95%,实现人员动态位置三维成像,救援效率提高至80%以上,有效缩短了煤矿事故救援时间,取得了显著应用成效。 相似文献
38.
岳城煤矿2135厚煤层工作面在开采实践过程中,片帮大块煤会造成带式输送机的堵塞,引发运输故障,需要停机检修。基于该问题设计了一种对大块煤进行有效破碎的装置,应用中设备操作简便,有效地解决了带式输送机机头卸载点和转载机入口的堵塞问题,为企业创造了较好的经济效益。 相似文献
39.
40.
The past few years have witnessed a dramatic growth in the number and variety of graphics intensive mobile applications, which allow users to interact and navigate through large scenes such as historical sites, museums and virtual cities. These applications support many clients and impose a heavy requirement on network resources and computational resources. One key issue in the design of cost efficient mobile walkthrough applications is the data transmission between servers and mobile client devices. In this paper, we propose an effective progressive mesh transmission framework that stores and divide scene objects into different resolutions. In this approach, each mobile device progressively receives and processes only the object’s details matching its display resolution which improves the overall system’s response time and the user’s perception. A fine grained cache mechanism is used to keep the most frequently requested objects’ details in the device memory and consequently reduce the network traffic. Experiments, in simulated and real world environment, are used to illustrate the effectiveness of the proposed framework under various settings of the virtual scene and mobile device configuration. Experimental results show that the proposed framework can improve the walkthrough system performance in mobile devices, with a relatively small overhead. 相似文献