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61.
采用低温反应射频溅射法在微晶玻璃上沉积了一层具有择优取向的氮化铝薄膜,再在其上沉积80Ni-20Cr电阻网络。对电阻网络进行了功率老化、高温存贮、热冲击等可靠性试验,结果表明具有AlN薄膜的电阻网络性能得到很大提高  相似文献   
62.
The analytical design of differential amplifiers, the building blocks of an op-amp, requires an elegant, handy and computationally simple experimental method of measuring the d.c.super-gain of these blocks. This paper presents such an oscillation based test (OBT) by putting the Op.Amp. under test in the close loop of state variable filter. The oscillation frequency of the linearized system directly yields the d.c. open loop gain, the dominant pole and the second order non-dominant pole of test Op.Amp. The d.c. open loop gain of DUT is further authenticated by a novel method of frequency domain analysis using a super attenuator. The authentication is positive with 95 percent confidence level (ɛ, 0 percent, 9.64 percent) thereby establishing the validity of OBT method.  相似文献   
63.
The massive growth of cloud computing has led to huge amounts of energy consumption and carbon emissions by a large number of servers. One of the major aspects of cloud computing is its scheduling of many task requests submitted by users. Minimizing energy consumption while ensuring the user's QoS preferences is very important to achieving profit maximization for the cloud service providers and ensuring the user's service level agreement (SLA). Therefore, in addition to implementing user's tasks, cloud data centers should meet the different criteria in applying the cloud resources by considering the multiple requirements of different users. Mapping of user requests to cloud resources for processing in a distributed environment is a well‐known NP‐hard problem. To resolve this problem, this paper proposes an energy‐efficient task‐scheduling algorithm based on best‐worst (BWM) and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) methodology. The main objective of this paper is to determine which cloud scheduling solution is more important to select. First, a decision‐making group identify the evaluation criteria. After that, a BWM process is applied to assign the importance weights for each criterion, because the selected criteria have varied importance. Then, TOPSIS uses these weighted criteria as inputs to evaluate and measure the performance of each alternative. The performance of the proposed and existing algorithms is evaluated using several benchmarks in the CloudSim toolkit and statistical testing through ANOVA, where the evaluation metrics include the makespan, energy consumption, and resource utilization.  相似文献   
64.
提出了一种聪明的TD-LTE MIMO操作模式,它结合了波束成形技术和闭环反馈MIMO的优点。当eNB获得UE上行SRS参考信号的信道信息,L1进行基于码本的信道估计量化和标签化。L1将标签上传到L2,L2基于标签进行多用户调度,这样较好地解决了基于迫零的UE配对和L1/L2间跨层资源分配这两个问题。 L1无需更多计算便可生成波束成形的预编码矩阵。同时,提出了在可接受的次优性能下一种易实现的一般性框架。为了达到目标,给出了新的码本设计标准和快速预编码矩阵的生成算法。  相似文献   
65.
骆光烈 《现代雷达》2000,22(2):57-60
应用信号流图结合S参数分析了标网测量微波网络驻波和衰减的误差.推导出了N端口网络测量驻波和衰减时产生的最大测量误差公式.可供测试微波网络时作误差分析,也可供设计微波系统的人员在分配每个元件驻波和衰减参数时作参考.  相似文献   
66.
This study presents a new database of land use categories in Brazil at a spatial resolution of 30 arc-second (about 1 km2). The spatial representation of current major land uses formally combines agricultural statistics from Brazil's latest census of the year 2006 at micro-region level and the Food and Agriculture Organization 2010 forest statistics with spatial land cover data sets. Spatial allocation (“downscaling”) algorithms were applied to obtain a spatial distribution of seven major land use categories. Remaining shares in each grid-cell were termed residual land, and were categorized according to legal protection status, biodiversity value, and whether they belong to the territory of the Amazon biome. We found a total of 84 Mha residual land of which 37 Mha occurred outside the territory of the Amazon biome and was neither legally protected nor categorized as highly biodiverse land. The 37 Mha “available residual land” equates to 4.4% of Brazil's geographical area and to 50% of its current cultivated land area. We assessed land quality using the Agro-ecological Zones modelling framework provides land suitability and productivity estimates of the available residual land. Nearly one-third of land emerged of prime quality and is therefore promising for biofuel feedstock production. Analysis of potential food-fuel competition suggests that until 2030 productivity improvements on current pastures could accommodate land demand for Brazil's increasing cattle herd and expanding croplands. If these productivity increases could be achieved on current agricultural land, residual land could provide areas for the sustainable expansion of biofuel feedstock production.  相似文献   
67.
开发黄河防洪决策支持系统必须首先明确防洪调度决策的目标和流程,防兴调度决策的一般流分情报预报,预报分析,方案制作了方案运作4个阶段,决策的目标主要有:各份蓄洪工程的实时计度方案,防洪工的防过抢护方案,灾情估算,滩区,库区,分滞洪区的迁移安装置方案以及决策指令的下达等。本根据黄河下游不同级别洪水(中常洪水,大洪水,超标准洪水等)的处理原则和方案,指出了相应的高度决策目标。  相似文献   
68.
本文从电力系统和水电站群的角度出发,考虑电站的必然联系和水电群的整体运行,建立了规划水电站装机容量优化选择数学模型。该模型由水电群优化补偿调节计算子模型,水电群总工作容量优选子模型和规划水电站工作容量优化分配子模型三个子模型构成,通过三个子模型的逐步求解和多轮迭代,最后即可得到收敛的优化装机解。本文针对规划水电站工作容量优化分配子模型给出了增量判别求解方法。最后是将本模型方法应用于云南大朝山水电站  相似文献   
69.
Representative passive adaptive algorithms have been developed with a wide variety of applications. However, to the best of our knowledge, the attempt to unify or to compare them has not been clearly established in literature. In this article, we provide a passive adaptive framework which encompasses all those algorithms including the recently developed proportional‐integral (PI) adaptive scheme. A comparative analysis among performances of the passive algorithms is carried out by means of simulations considering the problem of passivity‐based adaptive tracking control of a simple pendulum. In addition, passivity property for PI algorithm is rigorously shown in case of linear parametrization. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
70.
In the real decision making, q-rung orthopair fuzzy sets (q-ROFSs) as a novel effective tool can depict and handle uncertain information in a broader perspective. Considering the interrelationships among the criteria, this paper extends Choquet integral to the q-rung orthopair fuzzy environment and further investigates its application in multicriteria two-sided matching decision making. To determine the fuzzy measures used in Choquet integral, we first define a pair of q-rung orthopair fuzzy entropy and cross-entropy. Then, by utilizing λ-fuzzy measure theory, we propose an entropy-based method to calculate the fuzzy measures upon criteria. Furthermore, we discuss q-rung orthopair fuzzy Choquet integral operator and its properties. Thus, with the aid of q-rung orthopair fuzzy Choquet integral, we consider the preference heterogeneity of the matching subjects and further explore the corresponding generalized model and approach for the two-sided matching. Finally, a simulated example of loan market matching is given to illustrate the validity and applicability of our proposed approach.  相似文献   
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