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The relative position of antenna elements will change because of the mechanical vibration of ship deck, which will dead to the difference of the wave path and result in the variation of scanning beam pointing direction.
All of that will affect the guiding performance and accuracy, and more seriously, shipborne MLS could not work.
Considering that, each element of the linear array is basically the same, the synthetic field intensity of elements can be approximated to (2) Considering, we can remove the constant factor of (2), and then (3) Figure 1 The position of element k Figure 2 The geometry of the element’s position error Visible, the array antenna pattern is the product of element antenna pattern and the array factor associated with the geometry of the array.
(7) According to the properties of sinc function, the direction of beam can be changed by controlling the phase, and the direction of beam can be expressed as (8) And that is to say, a scanning beam can be obtained by controlling the phase of each phase shifter. 2.2 The model of Antenna array’s vibration error The position of antenna elements shifts because of antenna array’s vibration, as shown in Figure 2.
Figure 3 Vibration modes of antenna element 3 Analysis of antenna’s vibration effects on the guiding performance of Shipborne MLS 3.1 Analysis of the influence of vibration component in the X-axis on guiding performance According to the vibration mode, the vibration amplitude in the X-axis can directly affect the scanning beam, and the received signal wave in azimuths of -60°，0°，60°is shown in figure 4.

Analysis on Critical Speeds of the Rail Vehicle Based on SIMPACK Lihua Wang a, Anning Huangb and Guangwei Liuc Faculty of Mechanical and Electrical Engineering, Kunming University of Science and Technology, Kunming, Yunnan Province 650093, P.R.
In order to figure out the dynamic characteristics of the rail vehicle, the coupling factors between the vehicle and track were considered [1].
Critical speeds are affected by the vertical and cross-level irregularities mainly.
The vertical irregularity Sv(ω) and alignment irregularity Sa(ω) are (1) (2) Where, Sv(ω) and Sa(ω) are vertical and alignment irregularity power spectral densities, cm2×m /rad, ω and ωc are frequency and cut-off frequency seperately, Aa and Av are parameters which taken irregularity amplitude, v is the speed of vehicle, k is factor, and generally it is 0.25.
Otherwise, if the real parts of eigenvalues are negative, the he vibration of the system will declined and take on convergence properties.

With the rapid development of China's industrial technology, Researching and developing the spring with independent intellectual property is imperative.
This disadvantage will affect the service life.In perpendicular direction of the shear direction, Exerting pressure F，Then do the shear stiffness test，In the shear direction，Exerting pressure and measuring deformation.
References [1] Hesheng Zuo .Mechanical impedance method and application[M]Beijing：Mechanical industry press .1987
The resonant vibration of mechanical theory and application .
Mechanical vibration study[M] Shanghai Jiaotong University Press. 1985.3

Manufacture of large and homogenous bulk pieces and wires for electro-mechanics, has posed a great challenge, due to the opposition between the poor mechanical properties of ceramics and the requirements of shape and working.
This thermal gradient produces thermal expansion unstabilities which affect to the distance between the sample and the Hall probe.
In the pictures we consider only a thin sheet of material so introducing a high shape factor that produces some convexity in the magnetic flux density distribution.
º2 the factor is just 1.95.
The current distribution is also affected by the field existing on the environment, produced by other conductors as in cables.

Introduction The non-destructive testing has been revealed to be an important tool for obtaining information about concrete properties of a structural element.
In the same way, the evolution and uniformity of certain fundamental properties of the material, such as strength and elasticity modulus, can be inspected in the structural element during construction or throughout a study period.
The first includes tests that estimate the strength and the elastic properties of the material.
It was fixed a 0.5 water-cement factor and a weight ratio of one cement to one fine aggregate to two coarse aggregate.
Properties of concrete.

In the process of grain refinement through phase transformation, driving force and the parent phase grain size are two key factors.
One of the features of this method is that the nanocrystallized structures can be controlled through austenite decomposition transformation, so that the properties of nanocrystallized steels can be improved.
During the heating process, the austenite grain size was mainly affected by soaking temperature and soaking time.
The number of quenching cycles also affected the austenite grain size.
A New and Simple Process to Obtain Nano-structured Bulk Low Carbon Steel with Superior Mechanical Property, Scripta Materialia, Vol. 46(2002),p. 305-310

Specifically, with decreasing size of the structures and increasing aspect ratio, the surface to volume ratio increases and therefore surface effects may become a dominant factor affecting the mechanical stability.
Such superhydrophobic property prevents aqueous solutions to penetrate in between the structures and can thus severely reduce the effectiveness of wet processing steps.
For silicon nanopillars of the same dimensions (AR 10: height 380 nm, average diameter 37 nm), replacing deionized water (DIW) (figure 2-a) by IPA (figure 2-b) reduces the cluster size formed after drying, but there is only a limited improvement because capillary forces can be reduced only by a factor of 3 (γH2O = 72 mNm-1, γIPA = 21 mNm-1 at 298K).
The most commonly used approach to estimate wetting properties is contact angle measurement.

The bearing dynamic load is affected not only by the torque on the gear shaft, but also by stress condition of the gear under different conditions.
According to the stress acting on the bearing in use and property characteristic of the bearing, the appropriate type of bearing is firstly determined, after combining with integral structural design requirement of the transmission, the specific model of bearing is selected, and then obtain the basic parameters of the bearing.
Meanwhile, if the calculated life of the bearing is too greater, after overall consideration of other influencing factor, we can replace with lesser bearing in order to diminish the whole dimension of the transmission.
MASTA modeling of transmission system Establishment of gear shaft: According to the design drawings, 20CrMnTi was selected as the material of gear shaft of automobile transmission because it possesses better mechanical properties.
Because the transmission bearing is directly installed on the housing of the automobile transmission, the deformation of the bearing will affect the deformation of the housing and then give rise to more large vibration and noise.

The investigations have resulted in recognition that with control of some parameters, result in certain morphologies of ferrite, the mechanical properties of steel with these ferrite structures are improved.
The austenite to ferrite transformation and growth of different ferrite morphologies are important because by controlling growth of different ferrite morphologies, the mechanical properties of steel are improved [1,2].
Observation of the mechanical properties of materials with different ferrite microstructure has shown that Widmanstatten ferrite, upper bainite or grain boundary ferrite are detrimental to toughness, whereas intragranular ferrite improves it.
It is believed that propagation cleavage cracks are frequently deflected as they cross an acicular ferrite microstructure with its different orientation and this increases mechanical properties, especially toughness.
[5] Compendium of Weld Metal Microstructures and Properties. (1985), Cambridge: The Welding Institute

Improvement of Drill Life for Nickel Super Alloy by Ultrasonic Vibration Machining with Minimum Quantity Lubrication Hiromi Isobe1, a and Keisuke Hara2,b 1Nagaoka University of Technology, Department of Mechanical Engineering, Kamitomioka 1603-1, Nagaoka, Niigata 9402188, JAPAN 2Ichinoseki National College of Technology, Department of Mechanical Engineering, Takanashi, Hagisho, Ichinoseki-shi 0218511, JAPAN aisobe163@mech.nagaokaut.ac.jp, bhara@ichinoseki.ac.jp Keywords: Ultrasonic vibration, Ultrasonic Machining, Cutting Fluid, MQL, Heat-resisting alloy.
The production cost by using laser, electrical discharge and electron beam machining is expensive and the heat-affected layer greatly influences the property of productions.
For drilling of small and deep hole, application method of cutting fluid are important factor which is affect on tool life.
On the other hand, deviation of drilled hole position is affected by biting of chisel edge.
Chip load, which is a function of feed rate and spindle speed, strongly affects the productivity.