Intensity: n强度 sequence：n一连串，顺序
A common practice is to determine the percentage of time the recorded field data indicated（指示） vibration（振动） events were within the low and high acceleration ranges and run the simulation（模拟） at those levels for the same percentage of time. For example , if the field data analysis indicated the recorded events were at or above the high intensity point for 12% of the actual field trip and the laboratory performance simulation is set for three hours, the resulting laboratory test would utilize（使用） the high profile for 21.6minutes(12% of 180 test minutes)and the remaining 158.4 minutes of the total test time would be used to simulate the low intensity input profile .If more than one mode of transport is used ,it is recommended that separate（分隔） profiles be developed for each mode .Each mode may also have high/low spectra（光谱） components for the simulation .Figure 3.17 shows a testing sequence that is designed to simulate air ride （又叫lifted air suspension，中文是空气悬挂，是一种减震系统） truck（一种特殊车辆，中文名叫“气垫车”，主要用途是运输对震动比较敏感的货物，例如一些电子设备，还有飞机的零部件等）,rail（铁路） and leaf spring truck（板簧卡车，钢板弹簧是汽车非独立悬挂装置中的一种常用的弹性元件，广泛应用于货车、大客车、微型面包车后悬架上） from Rochester ,New York to Los Angeles, California . The duration（持续时间） of each component（组成部分） of the test cycle may vary .Some packaging professionals may run the simulation in the same time frame as the actual shipment .Others may accelerate the test to shorten the time .The decision must be carefully considered and validated（验证的） by comparing laboratory damage results with those seen in the field.
一个常见的做法是确定记录的实地数据表明振动事件在低和高加速度范围内的时间百分比，并在相同的时间百分比内在相同条件下进行模拟。例如，如果实地数据分析表明，所记录的事件在实际实地考察的12%达到或超过高强度点，实验室性能模拟定为3小时，由此产生的实验室测试将利用高姿态的21.6分钟(180分钟的12%)，其余158.4分钟的总测试时间将用于模拟低强度输入剖面。如果使用一种以上的传输方式，建议为每种方式分别开发配置文件。每个模式也可能有高/低光谱成分的模拟。图3.17显示了一个测试序列，它被设计用来模拟从纽约罗切斯特到加州洛杉矶的气垫车、铁路和板簧卡车。测试周期的每个组成部分的持续时间可能不同。有些包装专业人员可以在实际装运的同时进行模拟。有些人可能会加速测试以缩短时间。必须通过将实验室的损害结果与实地观察到的结果进行比较，认真考虑和验证这一决定。
It is also suggested that the test packages be evaluated（对hellip;作评价） in all relevant（相关的） axes（坐标轴） .Non-unitized shipping containers would be evaluated in all three orthogonal（垂直的） axes based on measured field orientations（取向） or as recommended by appropriate test standards and procedures from ASTM(2009)and ISTA(2009).
还建议在所有相关轴上对测试包进行评估。将根据所测量的朝向或根据ASTM(美国材料与试验协会American society for testing material)（2009年）和ISTA（国际安全运输协会international safe transit association）（2009年）的适当试验标准和程序的建议，在所有三个正交轴中对非单一化的海运集装箱进行评估。
Unpublished studies have suggested the testing protocol（草案） for defining the intensity of the simulation can be refined by determining the probability that the energy level of the transport input will reach given power density levels .By analyzing the number of times that the recorded field data reach specified PSD（Adobe公司的图形设计软件Photoshop的专用格式。PSD文件可以存储成RGB或CMYK模式，还能够自定义颜色数并加以存储，还可以保存Photoshop的图层，通道，路径等信息，是目前唯一能够支持全部图像色彩模式的格式） levels ,test intensity levels can then be set for percentage values at or below the specified spectra .The packaging professional could then determine the degree of confidence required in any given test profile based on the severity of the rmsg.（均方根值）
未发表的研究表明，确定模拟强度的测试文件可以通过确定传输输入的能级达到给定功率密度水平的概率来完善。通过分析记录的数据达到规定的PSD水平的次数，然后可以将测试强度水平设置为在规定的光谱或低于该光谱的百分比值。然后，包装专业人士可以根据测试结果的均方根值确定任何测试文件需求的信任程度。
Figure 3.18 takes a similar approach and displays a composite profile based on actual field data with the zero-to-peak acceleration probabilities given as percentages.
图3.18采用了类似的方法，并显示了一个基于实际数据的综合剖面图，以百分比表示的从零到峰值加速度概率。
Packaging professionals can investigate these and other modifications（修改） to random vibration simulation protocols, to determine which provide the best level of validation with actual field damage experience.
包装专业人士可以调查这些和其他对随机振动模拟草案的修改，以确定哪一个为实际损坏实验数据提供了最好的验证水平。
3.6.2 Kurtosis
曲线的峰态；峭度
Another feature of measured field vibration data that is of concern with regard to the manner in which the data are typically analyzed and put into simulation profiles, is the presence of kurtosis. Kurtosis addresses the non-Gaussian nature of vibration data which can be caused by the occurrence of significant variation in the instantaneous（即时，瞬时） peak acceleration values recorded.
测量到的振动数据的另一个特点是峰度的存在，这与数据通常被分析和放入模拟剖面的方式有关。峰度处理振动数据的非高斯性质，这可能是由记录的瞬时峰值加速度值发生显著变化所造成的。
Kurtosis is an indicator of the amount of measured variation present .Low values of kurtosis correspond to low levels of variation in peak acceleration values ,and high kurtosis values indicate more high level peaks and more low level peaks .It can be shown mathematically that a kurtosis level of three would be found in Gaussian vibration data(Kipp,2008).
峰度是衡量存在的变化量的一个指标。峰度的低值对应于峰值加速度值的低变化水平，而高峰度值则表示更高的峰值和更低的峰值。可以用数学方法证明，高斯振动数据中的峰度水平为3（kipp，2008年）。
Acceleration-time histories of two recorded vibration inputs ,from Vibration Research Corporation ,can be seen in Figure 3.19 (Van Baren,2005;Kipp,2008).The top plot has a kurtosis value of three and the bottom kurtosis level is seven .The top plot appears to be fairly uniform with regard to the overall shape and level of peak values .The bottom plot has higher peaks ,indicating more time was spent at higher acceleration levels during the period of the recording .However ,each plot has the same Grms intensity .This example demonstrates（表明） visually the potential problem of relying only on the averaged PSD profile as the simulation input.
振动研究公司有两个振动输入的加速时间历史，见图3.19（Van Baren，2005；Kipp，2008）。上图的峰度值为3，下图的峰度值为7。就整个形状和峰值水平而言，顶部似乎相当一致。底图有较高的峰值，表明在记录期间有更多的时间花在较高的加速度水平上。然而，每个图都有相同的加速度的均方根强度。这个例子从视觉上说明了仅仅依靠PSD数据的平均值作为仿真输入的前提。
Methods of kurtosis control that will increase the amplitudes（振幅） of the simulated acceleration peaks while maintaining the same Grms and the same spectrum（光谱） have been proposed（提议的） (Van Baren,2005).Currently this method is in limited use because the standard software used in laboratory
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