冷板冷藏车振动分析及隔振措施

建立了冷板冷藏车的动力学模型，运用模态分析方法建立相应的数学模型，分析了冷板冷藏车的振动特性，提出了在刚性冲击前提下的隔振方法。计算分析表明，在刚性冲击前提下所采用的隔振方法可以达到隔振的目的。     

公路服务商业化经营与企业经营行为

综合经济学和交通工程学理论,以公路服务的经营特性、市场需求和市场细分为基础,研究了公路企业的经营目标、收费价格确定方法、收费定价策略与调价方法,进而分析和得到了公路企业的经营方法。实践证明,经营方法使得公路企业的收费经营行为更为科学,增加了收费收入;公共管制方法在合理考虑企业利益的同时,能够约束公路企业的追利行为,减少社会福利损失。这对公路企业经营收费公路和政府对公路企业经营行为的管制,具有指导意义。     

ALTERATION IN CONTRACTILE RESPONSE TO NORADRENALINE,5-HYDROXYTRYPTAMINE, SARAFOTOXIN 6c, AND ANGIOTENSINⅡ IN RAT MESENTERIC ARTERY DURING ORGAN CULTURE

Theresistanceinindividualvascularbedsdeter minesthelocaldistributionofbloodflowtoandwithindifferentorgans.Thecontractilestateofanarteryiscontrolledbymediatorsreleasedlocallyfromnerveterminalsandendothelialcells ,andbycirculatinghormones .Thesemediatorsgiverisetoeffectsthroughtheirreceptors .Mediatorscanaffectvascularsmoothmuscleei therdirectly ,byactingonthesmoothmusclecellsthemselves ,orindirectly ,byactingonendothelialcellsoronnerveterminals ,especiallythoseofthesympatheticnervoussystem .Som…     

THE EDDY LOSSES OF A MAGNETIC THRUST BEARING

Accurate calculations of losses associated with the operation of magnetic bearings are particularly important for high speed applications where the rotor losses are expected to be large and for some particular applications where even low power losses will be critical. Power losses in the magnetic thrust bearing is often neglected, but if there is misaligned in the rotor and bearing, the magnetic field in the thrust bearing is no longer axisymmetric one, or the dynamic control current in the winding is time dependent one, eddy currents are caused to flow inside the conducting material, then the power losses are very important for magnetic bearing design. This paper presents an analytical model of a thrust magnetic bearing, and the magnetic fields, forces and losses of thrust magnetic bearing are calculated. In the calculations the frequency of dynamic control current is up to 1 000 Hz, rotating speed is from 60 rpm to 1 200 rpm, and the non-linearity of material is also taken into consideration. The results shows that if the magnetic field is not saturation, the eddy losses is proportional to dynamic control current frequency and a square function of dynamic control current, and also 5/2 power function of shafts speed.     

Local Search Algorithm with Hybrid Neighborhood and Its Application to Job Shop Scheduling Problem

A new local search method with hybrid neighborhood for Job shop scheduling problem is developed. The proposed hybrid neighborhood is not only efficient in local search, but also can help overcome entrapments while search procedure get trapped at local optima and carry the search to areas of the feasible set with better prospect. New strategies used for breaking out of entrapments are presented and they are helpful for the procedure to improve local optima. A performance comparison of the proposed method with some best-performing algorithms on all 10-job, 10-machine benchmark problems and the other two problems generated by Fisher and Thompson ( ie. , FT6 and FT20) is made. The experiment results show the better optimal performance of the proposed algorithm.     

Network Decomposition and Maximum Independent Set Part Ⅱ：Application Research

According to the researches on theoretic basis in part I of the paper，the spanning tree algorithms solving the maximum independent set both in even network and in odd network have been developed in this part，part Ⅱ of the paper．The algorithms trans form first the general network into the pair sets network，and then decompose the pair sets network into a series of pair subsets by use of the characteristic of maximum flow passing through the pair sets network．As for the even network，the algorithm requires only one time of trans formation and decomposition，the maximum independent set can be gained without any iteration processes，and the time complexity of the algorithm is within the bound of O(｜V｜^3)．However，as for the odd network，the algorithm consists of two stages．In the first stage，the general odd network is transformed and decomposed into the pseudo-negative envelope graphs and generalized reverse pseudo-negative envelope graphs alternately distributed at first；then the algorithm turns to the second stage，searching for the negative envelope graphs within the pseudo-negative envelope graphs only．Each time as a negative envelope graphhas been found．renew the pair sets network by iteration at once．and then tum back to the first stage．So both stages form a circulation process up to the optimum．Two available methods，the adjusting search and the picking-off search are specially developed to deal with the problems resulted from the odd network．Both of them link up with each other harmoniously and are embedded together in the algorithm．Analysis and study indicate that the time complexity of this algorithm is within the bound of O(｜V｜^5)．     

EFFECTS OF TOTAL SAPONINS OF PANAX NOTOGINSENG AND LIGUSTRAZINE ON THE PROLIFERATION OF CEREBRAL MICROVASCULAR ENDOTHELIAL CELLS OF RATS

Ｅｎｄｏｔｈｅｌｉａｌｃｅｌｌｓ (ＥＣｓ)ｆｕｎｃｔｉｏｎａｓｔｈｅｂａｒｒｉｅｒｏｆｔｈｅｂｒａｉｎａｎｄｒｅｌａｔｅｔｏｔｈｅｓｅｃｒｅｔｉｏｎｏｆｓｏｍｅｅｎｄｏ ｃｒｉｎｅｓ.Ｔｈｅｉｒｄｙｓｆｕｎｃｔｉｏｎｉｓｃｌｏｓｅｌｙｒｅｌａｔｅｄｔｏｔｈｅｏｃｃｕｒｒｅｎｃｅａｎｄｄｅｖｅｌｏｐｍｅｎｔｏｆｃｅｒｅｂｒａｌｖａｓｃｕｌａｒｄｉｓｅａｓｅｓ[1] .ＤａｍａｇｅｔｏＥＣｓｉｓｔｈｅｆｉｒｓｔｓｉｇｎａｎｄａｂａ ｓｉｃｆａｃｔｏｒｏｆｃｅｒｅｂｒａｌｉｓｃｈｅｍｉａ .Ｔｈｅｒｅｆｏｒｅ ,…     

国外主要大城市轨道交通客运服务特色的启示

标准化是城市轨道交通实现一体化、网络化的基础和前提。介绍了城市轨道交通客运服务的内容，从列车运营、票制设定、车辆设施、站厅环境、信息服务以及主管部门等方面总结了纽约、伦敦、巴黎和东京等主要大城市的地铁客运服务方面的成果和经验。指出服务标准化是保证和提高轨道交通客运服务水平的必要手段，提出制定我国地铁客运服务标准化的建议。     

骨质疏松性骨折愈合过程中骨痂局部生物力学改变的实验研究

目的　探讨骨质疏松骨折动物模型愈合过程中骨痂局部生物力学性能的变化。方法　利用大鼠骨质疏松胫骨骨折模型 ,测量了骨痂局部弹性模量和极限强度的变化。结果　骨质疏松骨折愈合过程中 ,弹性模量和极限强度均随着骨折愈合过程的进行而增加 ,在骨折后 3 5d编织骨完全形成后 ,极限强度与非骨折组相比无明显差别 ,而弹性模量尚有明显差别 ;在同一时间点与正常骨折组相比均无明显差别。结论　骨质疏松骨折骨痂局部的弹性模量及极限强度的变化模式与正常骨折骨痂相比无明显差别。     

基于SVM分类器的道路湿滑图像分类方法研究

在恶劣天气下路面湿滑状况将发生显著变化,导致驾驶条件恶化,极易引发恶劣的交通事故.为了帮助交通管理部门实时获取路面湿滑状况信息,了解路面附着性能,并以此制定合理的车速控制和交通诱导策略,通过采集道路湿滑图像,利用设计的具体SVM分类器结合3种训练算法对道路湿滑图像进行分类学习训练,并通过训练后的SVM分类器对大量道路湿滑图像进行分类实验,对道路湿滑状态进行分类研究.实验结果表明:(1)寻找合适的核函数,选择合适的参数是使用SVM进行高效分类的一个重要因素;(2)在训练过程中,均方误差(MSE)能反映出分类器实现的正确率,SVM的训练本身的误差决定了分类的正确率,而且训练个数的增多带来了特征空间维数的增加,从而导致计算量的增大.