首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
河南黄泛区农场建设对产业集聚发展的影响度研究   总被引:1,自引:1,他引:0  
通过利用区位熵指数、农业GDP份额和集中系数来描述河南省黄泛区农场产业集聚状况,以判断黄泛区是否存在产业集聚的现象;同时分析黄泛区农场产业集聚特征和并指出农场影响产业集聚发展所存在问题。  相似文献   

2.
GPS/INS integrated systems are applied in the self-positioning of the high dynamic targets. This paper forms state equations and observation equations by the integrated system and GPS observation respectively. An adaptive filtering algorithm is introduced which estimates observation noise covariance with observation data, and estimates dynamic noise covariance by use of Sage-Husa filtering algorithm which has faster convergent speed and better stability than the conventional Kalman filtering algorithm. At last, simulations are given to verify the effectiveness of the algorithm.  相似文献   

3.
A fast median filtering algorithm basing on the coherence of data in adjacent windows is presented.During median filtering,only the first median value is found by conventional squencing algorithm,the other median values are obtained by bisecting search method and quickinserting new element in sequenced window.For convenience of moving filter window along signal data,a data structure is desinged,which can make the new input element to cover output element and greatly reduce the quantity of computation.A 2-dimensional fast median filtering method by moving filter window along snack path is also introduced.  相似文献   

4.
It's always difficult in technology to eliminate power interference of 50 Hz in Brainwave Data Acquisition System .Though traditional ways to eliminate it can also gain some effects, they have drawbacks such as high cost and low currency at all time. The use of trap filter of 50 Hz may solve the question radically. Through the authors' repetitious experimentation, it is proved that trap filter of VCVS not only eliminate power interference of 50 Hz farthest but also have merits of simple circuit structure, convenient coupling and upper reliability. The authors offer collected brainwave in strong power interference environment. It may be seen that it is very clear and clean. Because power interference of (50 Hz) exists in almost all Data Acquisition System, this type of trap filter possesses better currency, it is expected to win extensive application in medical apparatus of measurement of other biological electricity signals and industrial observation and control system.  相似文献   

5.
The Kalman filter algorithm can be used to estimate the state of charge (SOC) of power batteries, however, it easily causes divergence due to uncertain of system noise and its estimation performance is affected by model. An adaptive Kalman filter algorithm is adopted to dynamically estimate SOC of lithium iron phosphate batteries for application in electric vehicles. At first, an equivalent circuit model, appropriate for SOC estimation is built after studying battery models. Then some charging and discharging experiments are carried out for parameter identification and the results are verified. At last, the adaptive Kalman filter algorithm is used on this model for on-line SOC estimation under unknown interfering noise. Simulation results show that adaptive Kalman filter method can correct SOC estimation error caused by tiny model error online, and the estimate accuracy is higher than Kalman filter method. Adaptive Kalman filter algorithm can also correct the initial error. Full-cycle test in electric vehicles proves that the algorithm is appropriate for SOC estimation of lithium iron phosphate battery.  相似文献   

6.
温室环境条件特别是温度对于作物生长和发育具有十分显著的影响。日光温室调控的主要环境因子之一是温度。然而,自然环境下的光照对温度产生作用,影响空气温度的监测精度。采用机器学习中的支持向量机算法(SVM),对日光温室内的温度智能监测算法进行了研究,根据光照情况对实时监测的温度数据进行校准。通过与实验测量的数据进行对比分析,结果表明:所提出的监测方法可以较为准确地实时监测空气温度,从而无需使用隔热材料或者遮阳处理,就可以基于监测的数据更精确地对相应的环境因素进行调节。基于该方法,可采用常用的工业设备实现温室大棚内实时温度数据的监测,既可以节约设备和人力成本,又可以为温室控制提供准确的数据。  相似文献   

7.
It is still a major problem for research on online monitor dielectric dissipation factor of high voltage equipment insulation. In the field, new methods are paid attention by researchers especially. At present, there are no methods achieving the satisfactory measurement results. Based on the voltage and current at their respective zero crossed points, this paper proposes the integral measurement method which can be used to measure the dielectric dissipation factor of high voltage capacitive apparatus. The formula for dielectric dissipation factor angle computation is deduced by theoretical analysis and the computation results are achieved by digital simulation. Meanwhile, this paper explains the effect to measurements by system frequency, content of harmonic and zero-drift and draws the relevant error curves. It also proposes the measures to reduce the integral measurement method presented in this paper,which can convert measurement of small signal into that of big signal and accurately measure dielectric loss of capacitive apparatus. It also possesses great anti jamming ability under strong electromagnetic interference environment. The online measurement system can detect the dielectric dissipation factor of high voltage equipment by the integral measurement method.  相似文献   

8.
Helmholtz coils produce uniform sinusoidal magnetic field in the center region, and the direction of magnetic field is approximate straight line, to help simplify the complexity of inverse problems. The simulation models of an 8-channel magnetic induction tomography measurement system are built, reconstructing conductivity distribution with filtered back projection algorithm. In the filtered back projection algorithm, the detected data is supplemented by the linear interpolation first, and then filtered by the Hamming filter, while adding a window filter to reduce the impact of around the coil from the divergence of the magnetic field. The different noise ratio of noise is added in the detected data to test noise suppression ability of the algorithm. The experiment results show that this filtered back projection algorithm can reconstruct the conductivity distribution under this model.  相似文献   

9.
A novel scheme is present to improve the conversion accuracy of ADC. The proposed approach uses adaptive sinusoidal filter. For the measurement of the signal with given frequency, the automatic adjustment of filter coefficients is based on least mean-square error rule, which is a mathematical tool can be employed to make filter output signal achieve the best approximation to the needed one. Then based on the result, it is able to get the amplitude and phase of the measured signal accurately. MATLAB software is used to verify the effectiveness of the algorithm. It proves that adaptive filter has improved the accuracy and signal-to-noise ratio of ADC, which is equal to increase the conversion digits.  相似文献   

10.
This paper contributes to the empirical literature on systematic methodologies for the identification of industrial clusters. It combines a measure of spatial concentration, qualitative input–output analysis, and a knowledge interaction matrix to identify the production and knowledge generation activities of industrial clusters in the Federal State of Saxony in Germany. It describes the spatial allocation of the industrial clusters, identifies potentials for value chain industry clusters, and relates the production activities to the activities of knowledge generation in Saxony. It finds only a small overlap in the production activities of industrial clusters and general knowledge generation activities in the region, mainly driven by the high‐tech industrial cluster in the semiconductor industry. Furthermore, the approach makes clear that a sole focus on production activities for industrial cluster analysis limits the identification of innovative actors.  相似文献   

11.
The frequency band of conventional partial discharge (PD) measurement systems is selected just within several ten kilohertz. With the development of computer and digital signal processing techniques, wide frequency band (WFB) measurement systems have been used to detect PD in electrical equipment for its higher sensitivity. Nevertheless, the WFB measurement systems are easy suffered from the interference of strong field electromagnetism noises. A set of PD online monitoring system with frequency band from 50 kHz to 1 megahertz used for transformer is developed, in which pre-processing device and cascaded 2nd order IIR lattice notch digital filter are mainly used to suppress periodic narrow-band interference. With analysis of field monitored signal at a 220 kV substation, it is shown that the monitoring system not only can detect and extract the discharge pulse signal effectively, but also has the powerful capability of suppressing interference.  相似文献   

12.
An algorithm of incremental model predictive control is proposed to solve a class of industrial production process real-time tracking problems. The basic idea is to establish a predictive model by adopting speed response on the basis of tracking error, and realize the optimization of the second time performance by using the soft constraint of the increment of control quantity and the online rolling optimization method. The theoretical analysis and Matlab simulation results show that the control algorithm can obtain good tracking performance, smooth dynamic response of the controlled object and strong robustness of the closed-loop system.  相似文献   

13.
A new image denoising algorithm based on the complex direction of filter bands and BlockShrink is proposed. The image is decomposed based on the complex direction of filter bands to obtain the coefficients. Then, according to the coefficient correlation, the block threshold method is used to select the best block size and the threshold. In this way, the unbiased risk estimation of each sub-band is minimized. The algorithm is entirely data-driven easy to implement and with good visual effects. Experiments show that the proposed algorithm increase the PSNR by 0.6 percent compared with the algorithm based on DWT-BlockShrink transform, and the edge and countour information are more clearly.  相似文献   

14.
按照标准条件在吸烟机上抽吸20支卷烟并用剑桥滤片收集粒相物,于150 mL具塞锥形瓶中用90 mL萃取剂(蒸馏水与异丙醇体积比为1∶1),振荡萃取30 min后,测定萃取溶液的pH值。该方法方法相对标准偏差为小于1%,用于测定卷烟主流烟气粒相物pH值,结果令人满意。  相似文献   

15.
宏观经济环境的变迁、经济危机的影响、新材料、新技术的替代与应用、林产品消费观念的转变在一定程度上影响了云南林业产业的发展。如何从宏观角度预测和把握林业产业发展走势,对于发展以“大资源、小产业”为特征的云南林业产业具有现实意义。笔者以2000-2008年云南林业产业产值数据为依据,通过检验GM(1,1)模型的通过性与精度,建立林业产业发展产值的白化方程与时间响应式,对2010-2014年云南林业产业产值的发展趋势进行了预测。通过预测结果,笔者展望了今后5年云南林业三次产业增长速率与发展规模,比较了三次产业发展的快慢程度,并对未来云南林业产业发展预测与评价的分析方法进行了探讨。  相似文献   

16.
A method of solving the problem of shoe leather lumen measurement in shoe CAD/CAM by industrial CT technology is introduced,X ray industrial CT technology is studied. The paper gives a rational scheme of system dispose. This scheme can be not only meet the need of shoe leather lumen measurement, but also achieve ordinary measurement. An uncomplicated and practicable movement control system are proposed also. This scheme achieves high precision of movement position without expensive direct current servo-control. A new simple method measurement is developed and accurate control of position in movement of detector data insert is achieved. The image resolving power can meet shoe leather lumen measurement.  相似文献   

17.
郭胜  凌霞  李文慧  杨莹 《保鲜与加工》2021,21(9):105-110
依据CNAS-TRL-010:2019《测量不确定度在符合性判定中的应用》中的合格概率计算公式计算冻猪肉样品的合格概率,再结合符合性判定结论得到冻猪肉中挥发性盐基氮符合性判定的误判概率,为实验室准确评估误判风险提供依据.结果表明,当容许上限为15 mg/100 g,测量值为14.9 mg/100 g,标准测量不确定度为0.23 mg/100 g,符合性判定结论为合格时,误判概率为33.4%.  相似文献   

18.
After completion of Three Gorges Reservoir at Yangtze River, protecting and improving the ecological environment of this area is becoming increasingly important factor in comprehensive progress of the economy and society of Chongqing City. The industrial solid wastes are one of the crucial factors influencing the environment quality of Three Gorges Area and they are also the hot and difficult problems influencing the development of economy and society of Chongqing City. At this point, firstly, the discharge, present situation, prospect and development of treatment and utilization of industrial wastes in Chongqing are summarized. Secondly, the experience at home and abroad are analyzed. Then, the way and foreground for recycling the wastes with new technology are also discussed. Finally, countermeasure for treatment and utilization of industrial solid wastes after completion of Three Gorges Reservoir at Yangtze River is brought up. The study on treatment and utilization technology of industrial solid wastes will be beneficial not only to the protection of ecological environment of Three Gorges Area, but to the development of new Chongqing City as well. In a word, it will have great environmental, social and economic benefits.  相似文献   

19.
滤泥作为制糖工艺的固体废弃物,对其主要研究方向是工业生产方面,而关于制糖滤泥还田的研究鲜见。为了揭示大田滤泥施用量对土壤中碱解氮、有效磷、速效钾、pH以及对不同品种甜菜(KWS 1197、KWS 7748、KWS 1479和Beta 2730)产糖量的影响,试验设置不施加滤泥(CK)、滤泥施用量为3750 kg/hm2 (A1)和7500 kg/hm2 (A2) 3个处理。结果表明:通过分析土壤氮磷钾以及pH对甜菜产量的影响,得出KWS 7748(高产型)品种最适宜的滤泥施用量是3750 kg/hm2,不仅能够增加甜菜的根产量,而且能够增加含糖量;KWS 1497(标准型)、KWS 1179(高糖型)和Beta 2730(标准型)品种最适宜施用7500 kg/hm2的滤泥,均能够达到增产的效果。施加不同量的滤泥对种植不同甜菜品种土壤中氮磷钾、pH及甜菜产量之间存在着很大差异。  相似文献   

20.
A new method for screening wheat for boron tolerance has been developed to overcome the problems of methods used in the past. Seedlings were grown for 10 days while suspended over B-rich solutions. Their root lengths were then measured as an index of tolerance. Five varieties of wheat were screened at seven concentrations of B. Results were obtained more quickly and easily than from the alternative methodologies and compared favourably. Screening of 128 doubled haploid lines from a cross between Halberd and (Wl*MMC) suggested that transgressive segregation had occurred. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号