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71.
通过对财务稽核的意义、作用以及电力企业内部控制的基本要求,阐述财务稽核对强化企业内部控制的重要性,同时列举电力企业管理中容易出现的财务管理方面的漏洞,并依次作为问题进行讨论寻找解决的途径。 相似文献
72.
给水管线造价公式的精确性对工程经济分析与给水管网优化的科学性和经济性有重大影响。通过五个地区的铸铁管综合单价数据,采用最小二乘法对各组数据进行多项式一至十次的拟合,确定了给水管线造价公式的最佳拟合次数为三次;进一步采用模拟退火算法对拟合的多项式参数进行优化计算,求解给水管线造价公式。结果表明:凭借模拟退火算法随机全局搜索模式以及不受函数性质影响的优势,能够克服传统算法难以求解多阶导数的困难,提高公式拟合精度。 相似文献
73.
基于标记的极半径极值红枣形状识别方法 总被引:2,自引:0,他引:2
形状是分级的最重要参数之一,本文采用标记法对红枣形状进行了识别。通过图像预处理获取红枣二值图像,通过边界追踪获取目标边界笛卡尔坐标,并将其转化为极坐标,对目标图像进行缩放旋转使均值圆成为基线,切割的4部分边界曲线能完整表达。对边界曲线进行多项式拟合,获取极值点坐标,将其映射回被拟合曲线上,获取对应极值点坐标。若两极小极半径差值大于阈值,则红枣畸形;若两极大极半径附近区域极半径过渡平缓,判红枣为规整,否则为较规整。取53粒红枣进行检测,其中16粒畸形,17粒较规整,20粒规整。检测结果表明:畸形枣识别准确率达100%,较规整枣的识别准确率94%,规整枣识别准确率95%,可基本满足红枣分级系统精度的要求。 相似文献
74.
基于当前嵌入式的流行,设计了一套嵌入式网络服务器,对其设计方案及主要芯片端口和功能进行介绍,将其应用到农业电网远程监测系统中的网络通信,给出了系统的功能框图,所涉及到的技术有数据采集技术、实时网络通讯技术等等。 相似文献
75.
76.
Xie Ming Guo Xiaoyu Wang Yanchun 《保鲜与加工》1993,(6):134-137
A minimum ring-band mathematical definition :In the done ring-band, there are at least two inner points and two outer points which scatter staggeringly on the circumference. With this definition as the rule of searching calculation' s ending,a fast numerical algorithm of gaining the minimum ring-band of a closed curve was suggested:Make a ring-band with the four points scattered staggeringly,then replace the old points with new ones continuously until all the points are located within the ring-band. The method was used in an application example to measure the spindle rotating precision of machine tools. 相似文献
77.
《Journal of Cereal Science》2014,59(3):451-456
Brans of 23 traditional and 12 improved (both red and white) rice varieties in Sri Lanka were screened for anti-amylase and anti-glycation activities in vitro. Varieties which showed the highest inhibitory activities at screening were further investigated for anti-glucosidase and glycation reversing as anti-diabetic properties. The same varieties were studied for selected antioxidant properties. Significantly high anti-amylase and anti-glycation activities were observed for bran extracts of red varieties compared to white varieties at screening. Traditional red rice varieties, Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti, exhibited significant and dose dependent anti-amylase, anti-glycation and glycation reversing activities. These varieties also showed marked antioxidant properties. It is concluded that brans of Sri Lankan traditional red rice varieties Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti may be potential food supplements for diabetes. 相似文献
78.
Wang Jianping Mi Linshu Chen Gang 《保鲜与加工》1993,(6):32-37
The angular frequency and decaying constant of each copmonect for the
transient waveform in power systems were obtained by using the discrete Fourier transform; the amplitude and phase angle were calculated in the linear curve fitting method. And all of the parameters obtained above were treated in an unified optimization by using the curve fitting optimization of the least square method of general nonlinear funcrion so as to get the results of waveform analysis. Two examples are included. 相似文献
79.
A method of measuring eyeglass lens power is proposed. A position detector and 3 beams of ray are used to measure the prismatic, spherical and astigmatic powers. Based on the method, an automatic focimeter with simple structure can be developed. The measure errors of prismatic and spherical powers are analyzed, from which it is concluded that the precision of the position detector is the key to the method. 相似文献
80.
With interconnecting and developing of power system, the problem of power flow computation on dispersed data resource need to be solved. A new distributed computation method of power flow based on Ward equivalent is presented. According to master-slaver splitting principle, multi-area interconnected power system is divided into master-slaver areas. Boundary buses in different areas are defined as different bus-types. Neighborhood areas are equivalent by Ward equivalent principle, and the equivalent injection power and equivalent impedance are worked out. Power flows from master area to slaver areas are solved by Newton method, and the equivalent injection power and equivalent impedance on the boundary are modified by their solutions. The process above repeats until to convergence. The proposed distributed power flow method takes full advantage of the information of power, voltage, network configuration in neighborhood areas, so it is better on convergence and quality of solution. The proposed algorithm is testified by IEEE 14-bus system and a practical 181-bus system. 相似文献