共查询到20条相似文献，搜索用时 31 毫秒
1.
In this paper, a new method of researching; the site dupleface dynamic balance of machine rigid rotator, namely duple test weightmethod is presented. Weight the new method against the existing method,namely single test weight method [1], both the efficiency increasing and theenergy-consumming dicreasing would be forty percent and over, with thebasic points of vibration theory, the formula of calculating weight andposition of the duple face dynamic unbalance of a rotator by means ofapplying the duple test weight is developed in detail. The method in handll-ing distinct bearing form is also discussed. Rightness of the new method isproved out by the living example of the simulant contrast testing carried outn the dynamic balance test machine and the site balance for a rotatorsystem of motor. 相似文献
2.
A lot of information needs processing in time in dynamic balance testing, but the current intelligent dynamic balance instruments and the controlling box of dynamic balance machines made up ofsinglemicrocontroller do not meet the request.A method isgioen that the DSP-Microcontroller will be useddiredtlyinthe system of the intelligent dynamic balance instrumentby using embedded design technique. A principal and subordinate control system compose of DSP and microcontroller. The Microcontroller the system as a principal controller and the DSP implements digital filtering and FFT in dynamic balanc by means of its fast operation. The system develoyed according tothe method can do more analysisin time areaand frequency area. 相似文献
3.
To control the oil contamination, the mathematical model is set up on the lubrication and hydraulic system and simulated the dynamic proceed in the real circumstance. The contamination degree is contamination level to be controlled and change the oil when system is dynamic balance. It is validated by the test and this result is useful to the act. 相似文献
4.
Fuzzy c-means (FCM) algorithm is dynamic cluster algorithm whose result often is local optimal decision. There often exists insignificant clustering in the result of Fuzzy c-means algorithm when traditional union, Intersection and inclusion work in fuzzy set. Our research indicates there are no insignificant clustering in the result of Fuzzy c-means algorithm over genetic algorithm and partial optimal solution can be avoided with this algorithm to a certain extent. The coding, select, corresponding crossover and mutation operators are designed. Finally we compared the performance of GFCM and FCM with testing data. Results show that the performance of GFCM is far better than FCM. 相似文献
5.
A distributed scheduling method in a networked manufacturing enviroment is given. A allocation algorithm for dynamic tasks in distributed systems based on LAN information in factories is introduced. The design goal is to obtain some better comprehensive targets, such as cost price, load balance, waiting time and efficient of systems. 相似文献
6.
A new quick thinning algorithm was presented in this paper,which assigneddifferent weights to different pixels near the skeleton pixels and rules out the im possible pixels in thethinning procedure. It needs neither iteration on pixel panel nor detection on every pixel such thatthe time consumed is greatly lessened. A filling algorithm is also offered for better results.Experiment on variety of binary patterns showed that it could get both a high speed and a goodskeleton shape compared with other algorithms,This new algorithm reaches perfect result. 相似文献
7.
An algorithm is proposed for dual-transistors forward converter (DTFC) by using the principle of charge balance control during a transient process to improve their dynamic performance. Combined with response curve,the theoretical analysis and some key equations are presented to improve the dynamic performance of the DTFC by minimizing the over/under shoot and the recovery time. In order to avoid the magnetic saturation of the transformer,an approximate method is introduced in the calculation of the optimal switching time,which can also be applied to other isolated converters when the maximum duty cycle is limited. Finally,the simulation results and the experimental results of the prototype show that,compared with the traditional voltage mode control,the proposed algorithm can significantly improve the dynamic performance of DTFCs. 相似文献
8.
Tongkou power station is an all-round hydro project,where the mixed exploitation mode is adopted with mainly for power generation.Integrated with the model test result,the duct discharge capacity and flow coefficient in various discharge hole are discussed,the influence of duct shape on inlet pressure,energy dissipation and tail water is analyzed,the improvement measures on conveyer way pressure and energy dissipation are put forward too.The achievements of this study have been adopted by the designers. 相似文献
9.
By improving the traditional digital concrete modeling method, the new defective concrete model was established. Three cases were simulated based on this model. The influence of initial defectiveness on the dynamic strength was investigated. The result shows that: 1) At initial stage, the influence of the initial defectiveness on the dynamic strength becomes more obviously with the increasing of the loading speed; 2) Regardless of the same loading speed, the influence becomes less obviously when the load reaches the strength point of the concrete; 3)The simulation result is compared with the test result, and it is deduced that the new model has higher computational accuracy and the result is more rational, and it can take the place of the traditional digital concrete model in practice. 相似文献
10.
ZHU Jia-fu~ 《保鲜与加工》2004,(7):50
Heart rate variability is an important index to express the tensility and balance of the parasympathetic-sympathetic nerve, and it is valuable to diagnose heart and blood disease in clinical diagnosis. It is approved that HRV signal possess non-linear characteristic, and we can analyse and present HRV signal with non-linear dynamic parameteres, such as fractal dimension. Based on phase-space reconstruction theory, an improved algorithm is introduced to calculate the correlation dimension of HRV signal, and some valuable conclusions are expressed according to the result which is concluded from the correlation dimension of nearly 30 samples. 相似文献
11.
Wind induced vibration is one of the main control factors in the Long span bridge structure design. The wind tunnel tests for measuring the static wind forces on the bridge girder and the section model wind tunnel dynamic testing for Caiyuanba Yangtze River Bridge in Chongqing are introduced in this paper. The wind tunnel testing for measuring static wind forces and vortex- induced vibration test on the arch are introduced taking account of the influence between two arches. The main contents and outcomes of testing are presented. It is indicated that the bridge girder has excellent wind stability and the arch mechanical characters are rather complicated. The drag force on the hind arch varied a lot because of the font arch interference on the wind flow. The drag force on the hind arch will be negative when two arches are close to each other. It increases with the space of two arches. The results of testing will give the data of buffeting and vortex - induced vibration and flutter analysis of the bridge. 相似文献
12.
Based on the modal assurance criterion, using simulated annealing algorithm, the dynamic characteristic data of cable-stayed bridge are extracted, optimal acceleration sensor layout scheme of main beam is obtained. According to this optimization scheme, we carry out a dynamic characteristics test on one cable-stayed bridge. The results between test data and finite element modal calculation are very closely. Theory technique research and field modal test demonstrated that the simulated annealing algorithm based on modal assurance criterion is effective and viable for optimal acceleration sensors placement of cable-stayed bridge. 相似文献
13.
14.
Load dynamic matching of supply and demand side based on the utilization of urban sewage heat energy
Flowing dynamic characteristics and its temperature dynamic characteristics of a three-level sewage pipe network in Chongqing were analyzed. A mall's building whole year load was simulated. In the adverse condition of wastewater flow, the market construction peak discharge heat was compared with the sewage heat load, the balance between the most adverse flow and the building demand was found. Explored supply and demand matching method between urban sewage and city building load in flow adverse condition to take full advantage of the urban sewage cold and hot resources. the composite system was adeptcd to make up the most unfavorable flow time of sewage average heat load and the construction load difference; it also puts forward principle of load sharing and control strategy aimed at compound system. 相似文献
15.
插电式混合动力汽车纯电动行进间启动发动机的平顺性控制 总被引：1，自引：0，他引：1
针对单电机插电式混合动力汽车在纯电动行进间电动机启动发动机时由于系统输出转矩变化进而引起整车冲击的问题,分析得到发动机点火时刻的不同及离合器接合状态的不同是造成转矩波动的原因。在此基础上,提出了基于离合器主、从动盘转速差和电机角加速度为输入量的离合器压力模糊控制的混合动力汽车模式切换动态协调控制策略,并对比了发动机目标转速点火和怠速转速点火的控制效果。最后通过台架试验以及实车道路试验对提出的控制策略进行了验证。结果表明,基于目标转速点火的协调控制策略能减小整车的冲击度。 相似文献
16.
The study on automatic balance of the rotor was made both from theory and ap-plication.In the light of the feature of automatic balancing,new analysis about the mechanical modelof vibratory system was done,and the result is that the accurate model of system can be gained bycompensation method and the traditional principle errors of balance machine both for soft and hardbearing can be overcome.The autornatic balance testing theory was proposed.The automatic balancesystem has been developed a nd the fu n ction a nd techn ical key are also discussed in detail. 相似文献
17.
研究河西东部枸杞品质评定指标,可为区域产业发展、品种优选以及品牌营销提供理论支撑。笔者以2016年试验数据为基础,将生长量指标与理化指标作为评价依据,采用熵权法和主成分分析对16个批次红枸杞进行各个评价指标的权重赋值,并借助动态赋值对两种评价权重进行综合赋值,然后利用评价模型有效实现了枸杞的品质评定,结果显示丰乐基地品质最为突出,评定结果与实际相符。本研究为河西东部红枸杞质量评定提供了基本方法。 相似文献
18.
冬前高温和播期密度对小麦苗期个体及群体生长的影响 总被引：1，自引：1，他引：1
在山西临汾采用连续递增密度试验小区设计法，开展了播期密度对小麦苗期个体和群体生长的影响研究。结果表明，在冬前气温偏高的年型条件下，播种密度在225~450万粒/hm2范围内，随着播种密度的增加株高增加，单株茎数、单株次生根数、单株绿叶数减少并存在显著性差异，而主茎叶龄则无显著性差异；播种期在9月24日~10月4日范围内，株高、主茎叶龄和单株次生根3个性状均随播种期的推迟株高降低、主茎叶龄和单株次生根减少，单株茎数和绿叶均为9月29日播种的居多；播种期和播种密度对株高、主茎叶龄、单株茎数、单株次生根数和单株绿叶性状的变异系数影响不同。9月24日和9月29日播种的4个播种量冬前群体均分别不足1200万/hm2和超过了1200万/hm2。本试验达到壮苗和合理群体指标的组合为播期10月4日、播种量225万/hm2 相似文献
19.
The differential equation which governs the behavior of the gear transmission system of 1.5 MW wind turbine is established. The external excitation caused by wind speed fluctuation is discussed and the internal excitation due to time varying mesh stiffness and comprehensive error is also analyzed. The calculating formulations of the harmonic balance method of nonlinear dynamic equations are presented. Then, the multi objective dynamic optimization model is developed to minimize the value of vibration acceleration and the overall volume. The optimization of a practical example using mixed discrete combined programming is performed. The result shows that the proposed method of modeling and optimization design can effectively reduce the wind turbines gearbox vibration levels and weight. 相似文献
20.
Methods for satisfying the power balance requirement and the voltage magnitude costraint are developed and incorporated into the genetic algorithm method to form a constrained genetic algorithm for solving the load flow problem.The robustness of the load flow algorithm is enhanced by the dynamic population.the technique for accelerating the convergence of the optimisation process and the network node sequencing procedure described in the paper.The efficiency and feasibility of the developed CGALF algorithm have been tested using KK 11 node system under light load and heavy load conditions. 相似文献