Measurement and analysis of delivery van vibration levels to simulate package testing for parcel delivery in Hungary

In the past several decades, there continues to be an increase in both domestic and international online and catalogue shipments that requires an increase in shipments and handling of parcels by single parcel delivery companies. This study measured the vibration levels that occur in parcel delivery shipments from pickup to delivery, especially the sections involving delivery vans and small vehicles over ground road transportation in Hungary. Goods that were shipped in the regions studied almost always travel at least once by van on varying road conditions such as motorways, main, side or city roads to deliver parcels to the final destination. The aim of this paper was to provide an understanding of vibration levels that occur during van transportation that can be used to pre‐shipment test new packages to prevent damage. The measured acceleration‐time data were analyzed in terms of power spectral densities (PSDs) and presented with statistical data to provide an understanding of the variability of intensity. The separated and averaged vibration levels that were measured in this study were compared with the American Society of Testing and Materials and the International Safe Transit Association vibration profiles for pickup and delivery vehicle in the form of PSD spectrums. Based on the analyzed data of this study, PSD spectra were provided for various route conditions as well as composite spectra, which can be used to simulate the measured vibration conditions representing van shipments.     

Measurement and analysis of truck and rail vibration levels in Thailand

Worldwide increase in trade, foreign direct investment, capital flows, migration and the spread of technology has caused an increased focus to be put on designing packages that can protect goods shipped globally. This requires a wide‐ranging understanding of the distribution environments on a global basis. Several past studies have mapped the vibration levels for surface transportation along the most popular shipment routes in countries such as Brazil, Canada, China, India and the USA. This study was conducted to provide a comprehensive understanding of the vibration levels observed for truck and rail shipments for major transportation routes in Thailand, one of the leading economies in the Southeast Asia region. Data recorders were used to collect the vibration data which were then analysed in terms of power spectral densities. Vibration levels observed from various segments of transportation are presented in the form of power density spectrums. Composite spectrums that can be used to simulate the measured vibration conditions in Thailand are presented. Copyright © 2010 John Wiley & Sons, Ltd.     

Comparison between lateral,longitudinal, and vertical vibration levels in commercial truck shipments

The widespread use of tractor trailers for the shipment of packaged products has brought about the need to be able to quantify accurately the nature of the shipping environment as it pertains to damage. The purpose of this study was to compare the levels of lateral and longitudinal vibration to vertical levels measured in the same truck trailer travelling over the average USA highway. Four truck-trailer shipments, two with light loads and two with heavy loads, were instrumented with accelerometers and recording equipment. From the data acquired, power spectral density plots were developed. The results showed that below 20 Hz, lateral and longitudinal vibration levels were generally much lower than vertical levels, but at frequencies above 20 Hz, all three were similar. The more heavily loaded trucks showed higher lateral and longitudinal levels of vibration than the lightly loaded ones.     

Measurement of Truck Transport Vibration Levels in China as a Function of Road Conditions,Truck Speed and Load Level

Transport vibration levels in trucks were measured as a function of truck speed, road conditions and load level. The trucks consisted of one normally loaded truck and one overloaded truck with leaf‐spring suspensions. Truck speeds were divided into three groups: 0–30 km/h, 31–60 km/h and 61–90 km/h. Traffic roads consisted of highways, arterial roads (ARs), secondary roads (SRs) and tertiary roads (TRs). The results revealed that transport vibration levels increased with truck speed; TRs contributed to the highest transport vibration levels, followed by SRs, ARs and highways. The power spectral density peaks were at 3 or 3.5 Hz. Overloading probably suppressed transport vibration levels especially at low speeds. Copyright © 2015 John Wiley & Sons, Ltd.     

基于并联空气弹簧结构的卫星运输减振系统设计及振动特性分析

随着航天科技的发展以及日益增长的性能需求,对卫星的可靠性要求越来越高,对运输过程中的振动也提出了更严格的要求,导致目前的减振系统难以满足未来的运输需求.针对这种情况,设计了基于空气弹簧并联结构的卫星包装运输减振系统,并对其振动特性进行了分析.结合卫星运输箱的结构和减振需求提出了并联空气弹簧减振系统方案.基于实测参数建立...     

基于物流运输环境的打印机包装方案分析

目的 研究打印机物流包装方案在运输过程中对打印机的防护性能。方法 对打印机整体包装件进行模拟公路运输路况的随机振动试验,得到产品的响应加速度谱密度曲线;然后建立打印机物流包装的三维模型,通过运用有限元软件Ansys Workbench中的随机振动分析模块（Random Vibration）对整体进行随机振动仿真分析,得到打印机的响应加速度谱密度、总位移、各向应力、等效应力等。结果 由仿真得到的响应加速度谱密度与试验结果相对比,其变化趋势一致,验证了仿真的可靠性,同时验证了该打印机包装方案具有良好的保护性能。结论 该打印机整体包装方案满足公路物流运输的防护要求,同时提供了一种物流运输包装方案的可靠性验证方法。     

水平滑台随机振动性能探讨

随着科技和经济的发展进步,随机振动已经成为振动环境工程和结构动力学研究中最重要的课题。本文重点就水平滑台的随机性能中的梯度现象就某一实例做了重点剖析及讲解,并对日常试验及检定检测中应注意的问题进行了探讨。     

A probability guided evolutionary algorithm for multi-objective green express cabinet assignment in urban last-mile logistics

In the past decade, urban last-mile logistics (ULML) has attracted increasing attention with the growth of e-commerce. Under this background, express cabinet has been gradually advocated to improve the efficiency of ULML. This paper focuses on the multi-objective green express cabinet assignment problem (MGECAP) in ULML, where the objectives to be minimised are the total cost and the energy consumption. MGECAP is concerned with optimising the purchase and assignment decision of express cabinets, which is different from conventional assignment problems. To solve MGECAP, firstly, the integer programming model and the corresponding surrogate model are established. Secondly, problem-dependent heuristics, including the solution representation, genetic operators, and repair strategy of infeasible solutions, are proposed. Thirdly, a probability guided multi-objective evolutionary algorithm based on decomposition (PG-MOEA/D) is proposed, which can balance the limited computation resource among sub-problems during the iterative process. Meanwhile, a feedback strategy is put forward to alternatively generate new solutions when the probability condition is not satisfied. Finally, numerical results and a real-life case study demonstrate the effectiveness and the practical values of the PG-MOEA/D.     

Vibration and acceleration levels of multimodal container shipping physical environment

In global supply chains, multimodal transportation plays a dominant role in worldwide shipping. The rail, truck, and vessel combination is the most commonly used mode for non‐time sensitive shipments between continents. This study focused on measuring the transportation environment effects (vibration and acceleration levels) in 40‐foot ISO container shipments using multiple modes of transport, originating in Hungary and destined for Mexico, India, and China over several weeks. The study also measured multimodal shipping routes without vessel transportation to China over Trans‐Siberian and Trans‐Manchurian railway lines. The transshipments and handling events in container hubs and terminals were separately analyzed. The results show the comparison of vibration intensity (in PSD) of different route conditions between various continents, and the possibility of acceleration levels during transshipments and handling events. The measured data show that extreme acceleration levels in vertical direction (9.37 G) occur while containers are handled in a seaport, and in lateral (4.45 G) and longitudinal (5.55 G) directions while they are transshipped by truck to rail container terminals. The rail vibration levels in Russia and China showed a lower intensity in the frequency range of 1 to 15 Hz, and higher between 15 and 200 Hz than in Europe; the lowest vibration levels occurred when the containers traveled on the sea, and truck vibration levels were very similar to previous research and ISTA protocols.     

Measurement and Analysis of Vibration Levels in Rail Transport in Central Europe

In the last decade, with a continued change in world economic conditions and global trade, transportation of goods has continued to increase. The opening of new and existing markets requires that products and packages move through various regions of the world using available logistical equipment and networks at a faster pace. It also requires that damage be kept at a minimum while providing maximum safety to individuals. This can be achieved by properly designing packages to transportation levels that occur in the supply chain. The purpose of this research is to both measure and analyse the vibration physical forces that occur during rail transport. Rail shipments are widely used across the world, and they are an integral part of the intermodal transfer of ISO containers from ships and trucks to rail. The aim of this paper is to provide vibration levels measured for rail shipments on a major railway line in Central Europe that has not been previously published. The vibration levels that were measured in this study were compared with American Society of Testing and Materials, United States Military Standards and United Kingdom Defense Standard standards and International Safe Transit Association procedures in the form of power spectral density spectrums. A composite power spectral density spectrum is provided which can be used to simulate the measured rail vibration levels in Central Europe. Results are also compared with rail travel in other international shipments for North America and Asia. Copyright © 2016 John Wiley & Sons, Ltd.     

Measurement and analysis of truck transport environment in Brazil

Increasing trade in today's global economy requires packaging to be designed to contain, protect and deliver products without damage during transportation and handling. Vibration forces that occur during transportation are one of the most significant causes of damage during shipping. The objective of this study was to quantify and analyse the vibration that occurs during truck transport in Brazil. The study was done using two types of trucks: small local trucks for local metropolitan distribution areas and larger tractor‐trailers for cross‐country transportation. Ten metropolitan areas in different regions of Brazil were selected for 1‐day trips representing normal delivery. These trips encountered varying road surfaces (asphalt, concrete, stone and dirt). The long distance trips were done on highways that were more than 1200 km long. The vertical vibration levels were higher than the lateral and longitudinal levels as expected. A composite power density spectrum of all trips is provided in this paper to simulate truck transport in Brazil using random vibration test methods. Copyright © 2007 John Wiley & Sons, Ltd.     

The role of transportation in the design and implementation of reverse logistics systems

This paper explores the role of inbound and outbound transportation within the context of a reverse logistics (RL) system. The transportation system is analysed and evaluated in terms of specific subsystems (sub-factors) associated with it. The data was collected from two in-depth case studies from two different industries. The research methodology utilised in this study is exploratory case study approach. The analysis of these case studies resulted in propositions and insights regarding RL practices with respect to a transportation system. The transportation sub-factors, propositions, and a framework for effective design and implementation of RL operations with respect to the transportation system are then presented. In conclusion, the results, managerial implications, and future research results are provided.     

Effect of vehicle speed on shock and vibration levels in truck transport

An update on the nature of shock and vibration in truck transport was obtained by measuring and analysing the shock and vibration levels separately that occur during truck transportation in Japan. The effect of truck speed on the shock and vibration levels was mainly analysed. A significant difference was observed between the acceleration of vibration, and the acceleration including shock and vibration as a result of truck speed. The results indicated that the effect of truck speed on root mean square acceleration (Grms), including shock and vibration, was strong at a lower speed, but slight at a higher speed. The highest Grms, including shock and vibration, was found at 45–59.9 km/h on local roads, which was higher than that during highway driving. When the speed was below 45 km/h, the peak power spectral density (PSD) of acceleration including shock and vibration increased as truck speed increased; when the speed was above 45 km/h, no significant changes in peak PSD were found because of truck speed. At the same time, the effect of vehicle speed on the vibration acceleration was also studied. It was found that the higher the vehicle speed, the higher the Grms and peak PSD value of vibration in both the vertical and lateral directions. Copyright © 2010 John Wiley & Sons, Ltd.     

Measurement and analysis of truck transport vibration levels and damage to packaged tangerines during transit

The purpose of this study was to measure the vibration levels in commercial truck shipments in Thailand and observe the effects on packaged fruit. The study measured the vibration levels in two of the most commonly used truck types to ship packaged goods as a function of road condition and vehicle speed. The suspension type on the trailers studied was leaf‐spring. The results of damage to packaged tangerine fruit as a function of location in the payload are also presented. The data presented in this study will assist product and package designers to reduce damage in transit. The results showed that vibration levels increased with speed and as a result of road condition. Analysis of variance indicated that three controlling factors, road surface, truck speed and truck type, significantly affected (p ≤ 0.05) peak PSD, PSD* (root mean square) over the frequency range 2–5 Hz, and fruit damage. As expected, based on previous work, an increase in truck speed resulted in an increase in vibration levels and damage to packaged fruit. The laterite road condition produced the highest vibration level for a given truck and travelling speed followed by concrete highway and asphalt road conditions. Fruit damage was found to be greatest in the uppermost container for every combination of road, truck type and travelling speed, which also corresponded to the highest vibration levels recorded. The results showed that a significant amount of damage can occur on unpaved roads (laterite), while the packages are transported from farms and harvesting areas to regional truck terminals. Damage on asphalt road conditions was minimal. This paper provides an updated history of measured and quantified levels of vibration for these specific trucks and road conditions. Copyright © 2005 John Wiley & Sons, Ltd.     

B2 功率超声振动系统的电声效率测量

本用导纳圆图法和谐振导计算法，分别对用于超声清洗和塑料焊接的两个振动系统的电声效率进行了测量，结果表明在小信号和功率输出下，其电声效率基本相等，测量误差不超过±１５％。为通过电声效率和电功率测量，确定功率超声振动系统的输出声功率提供了可能途径。     

Measurement and Analysis of Vibration Levels in Two and Three Wheel Delivery Vehicles in Southeast Asia

Different types of small vehicles such as two‐wheel and three‐wheel motorcycles are commonly used for domestic delivery in many countries in Asia, particularly in Southeast (SE) Asia. These types of vehicles are mostly used for delivery of packages in the last leg of the supply chain. This study was initiated at the Technical Council meeting of International Safe Transit Association to understand the vibration levels that exist in delivering packages in SE Asia for the ‘last leg’. The study measured the vibration levels that are experienced by packages in Thailand and Indonesia. The delivery process in these countries uses two‐wheel and three‐wheel light vehicles to deliver printers and small packages. However, this portion of data and testing has often been overlooked by packaging test standards used in North America and Europe to design and test packages during the development process. The ‘last leg’ delivery method discussed has generally been considered the fast, convenient and flexible way of product delivery. Data recorders were mounted on the vehicle floor to measure acceleration levels during delivery in commonly used routes in the major cities in these two countries. Measured data in this research show that the vibration levels in these ‘last leg’ delivery routes are actually lower than those measured in truck and container shipment across road and rail transportation in North America that has been previously studied by the authors. Vibration levels in the two‐wheel vehicles with rear trunk containers were higher than those in the three‐wheel vehicles. Copyright © 2015 John Wiley & Sons, Ltd.     

Life estimation model of a cantilevered beam subjected to complex random vibration

An analytic methodology was developed to predict the fatigue life of a structure experiencing stationary, Gaussian random vibration excitation. This method allows the estimation of fatigue life using a frequency domain method, where only the input power spectral density and damping factor are required. The methodology uses linear elastic fracture mechanics for fatigue crack propagation and accounts for the frequency shifting that occurs due to fatigue crack evolution. Good results have been obtained comparing the analytic model to both finite element analysis (FEA) and experimental results, for mild‐steel cantilever beams.     

B2功率超声振动系统的电声效率测量

本文用导纳圆图法和谐振导纳计算法，分别对用于超声清洗和塑料焊接的两个振动系统的电声效率进行了测量。结果表明在小信号和功率输出下，其电声效率基本相等。测量误差不超过±１５％。为通过电声效率和电功率测量，确定功率超声振动系统的输出声功率提供了可能途径     

人体长骨振动的在体测试

振动分析技术用来诊断骨病和估计骨折愈合程度的可行性已得到证实。测试时常用的激振方式有电动、人工和超声等，拾振装置有传声器、力传感器和加速度计等。文章采用医用叩诊锤激振、双加速度计拾振，在不同情况下在体测试了人体长骨的振动。通过分析测试信号的功率谱及传递函数，发现骨组织中振动传播具有方向性，拾振器的质量、测点及激振点位置对测试结果有影响。实际应用中应选用质量较小的拾振器，且应尽量保持待测肢与对照肢的测试条件一致。