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71.
With the development of 5G, big data, cloud computing, IOT, mobile Internet and other information technologies of new
generation, the design of forestry information system establishes a new mode of forestry development integrating three-dimensional
perception, collaborative management and internal and external services by means of perception, IOT and intelligence. Intelligent
forestry system is a comprehensive information management system integrating forest management, intelligent forestry business
management, green maintenance management and emergency command and dispatching management. Based on the specific project
practice, this paper puts forward the overall framework design scheme and management platform design scheme of intelligent forest-
ry. 相似文献
72.
The integration of computer theory and practice in higher vocational colleges is the necessary condition to realize the train-
ing of professional talents and improve the comprehensive quality of skilled talents. It is also the problem that needs to be solved
first in the teaching of computer major in higher vocational colleges. This paper firstly introduces the definition and connotation of
the integration of computer theory and practice, discusses on its construction objectives and basic concepts, then analyzes the con-
struction value of the integration of computer theory and practice, including the contents of employment, professional teaching, cur-
riculum supporting and qualification examination, finally discusses on the construction scheme of the training room of the integra-
tion of computer theory and practice, and gives the objective evaluation of the construction results, hoping to effectively improve the
level of the integration of computer theory and practice, and achieve the sustainable development of teaching. 相似文献
73.
伴随着互联网+的风生水起,信息量暴增的大数据时代应运而来,"网络原住民"大学生不可避免、理所当然地处于大数据洪流之中,但也为其个人隐私保护带来了极大挑战。文章针对大数据带来的安全隐私问题,指出大学生个人隐私泄露的可能原因,提出可以采取的个人隐私保护措施,给出大数据时代隐私保护几种技术,期望能给相关人士提供有效参考。 相似文献
74.
This article is concerned with the polynomial filtering problem for a class of nonlinear stochastic systems governed by the Itô differential equation. The system under investigation involves polynomial nonlinearities, unknown‐but‐bounded disturbances, and state‐ and disturbance‐dependent noises ((x,d)‐dependent noises for short). By expanding the polynomial nonlinear functions in Taylor series around the state estimate, a new polynomial filter design method is developed with hope to reduce the conservatism of the existing results. In virtue of stochastic analysis and inequality technique, sufficient conditions in terms of parameter‐dependent linear matrix inequalities (PDLMIs) are derived to guarantee that the estimation error system is input‐to‐state stable in probability. Moreover, the desired polynomial matrix can be obtained by solving the PDLMIs via the sum‐of‐squares approach. The effectiveness and applicability of the proposed method are illustrated by two numerical examples with one concerning the permanent magnet synchronous motor. 相似文献
75.
76.
ASME标准钢板对于短时高温抗拉数据无规定,但设备设计人员在校核时又要用到此数据,于是有些设计文件在技术要求中将ASME II卷表U的数据作为材料验收的标准。针对此种做法引发的争议及涉及的主要问题进行试验验证和分析探讨。研究结果表明,ASME II卷D篇表U中的数据是基于室温抗拉强度保证值,并根据拟合曲线将室温保证值提高了10%得到的,实测数据与ASME规范数据不一致,部分材料在250~350℃存在动态应变时效现象,但仍不满足设计要求。材料经模拟焊后热处理后性能下降,难以到达交货态的要求。给出了短时高温抗拉强度的选用建议。 相似文献
77.
目前国内外地层压力测井解释方法较多,但大多数方法基于欠压实沉积理论并局限于单一的地层岩性,尤其是针对盆地边缘山前深层构造,单一测井参数确定地层压力误差较大,且无法解释沉积压实机制以外的异常高压。为此,将多种异常高压机制相关的测井参数进行综合解释,建立适合山前复杂构造的地层压力测井多参数计算模型,评价准噶尔盆地南缘高泉背斜高探1井的地层压力剖面,其计算结果与钻井实测数据吻合,相对误差小于3.00%.同时,基于原始沉积加载—卸载过程力学原理,利用地层压力测井多参数分析判别出高泉背斜深层各层系异常高压的形成机制。 相似文献
78.
79.
《等离子体科学和技术》2020,22(1):15402
Laminar plasma jet(LPJ) generated by laminar plasma torch(LPT) has a favorable temperature and velocity distribution. Thus, it is superior to the turbulent plasma jet in material processing.However, most of the reported LPTs usually operate at a relatively low output power with a relatively low arc voltage and thermal efficiency, which limits its capabilities. In this context, this paper attempts to design a new type of high-power LPT with a relatively low arc current and a high thermal efficiency. In the first section, the design principle of the main components is studied and discussed in detail, and a new high-power LPT is proposed. Then, the experimental characteristics of the proposed high-power LPT are examined. Experimental results reveal the following characteristics of the proposed LPT.(1) The max jet length of the proposed LPT reaches at 540 mm.(2) Its mean arc voltage is higher than 290 V when the LPT works with arc currents lower than 200 A, leading to an output power greater than 50 kW.(3) The mean thermal efficiency is higher than 50%. Lastly, the proposed LPT has been applied to spheroidize the aluminum oxide powers. The experiment results for the production of spherical powders show that the proposed LPT has a good characteristic for material processing. 相似文献
80.
《工程(英文)》2020,6(7):812-826
Renewable energy sources (RESs) are considered to be reliable and green electric power generation sources. Photovoltaics (PVs) and wind turbines (WTs) are used to provide electricity in remote areas. Optimal sizing of hybrid RESs is a vital challenge in a stand-alone environment. The meta-heuristic algorithms proposed in the past are dependent on algorithm-specific parameters for achieving an optimal solution. This paper proposes a hybrid algorithm of Jaya and a teaching–learning-based optimization (TLBO) named the JLBO algorithm for the optimal unit sizing of a PV–WT–battery hybrid system to satisfy the consumer’s load at minimal total annual cost (TAC). The reliability of the system is considered by a maximum allowable loss of power supply probability (LPSPmax) concept. The results obtained from the JLBO algorithm are compared with the original Jaya, TLBO, and genetic algorithms. The JLBO results show superior performance in terms of TAC, and the PV–WT–battery hybrid system is found to be the most economical scenario. This system provides a cost-effective solution for all proposed LPSPmax values as compared with PV–battery and WT–battery systems. 相似文献