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The chemical industry is struggling to improve its supply chain performance, and improved asset utilization may help get the industry headed in the right direction. Since most chemical firms own or lease their rail fleets, rail utilization can have a substantial impact on overall asset utilization. The paper aims to focus on current managerial processes and situational factors that impact railcar asset performance.

Rail car cycle data are analyzed, focusing on major sources of variation in transit inventory as railcars move from plant to customer and back.

Findings include the importance of establishing and adhering to policies regarding supply chain practices; substantial differences exist between hopper and tank car performance; distance is not a major predictor of total cycle time variance; and vendor‐managed inventory relationships can operate with less customer inventory.

This paper addresses only one component of supply chain performance: railcar cycle time. Further analysis is needed to investigate differences between hopper car and tank car transit times. Additional research should also involve the railroad companies as participants in chemical firms' supply chains.

The paper provides several practical recommendations for chemical company supply chain managers relating to process controls, focusing on large customer accounts, managing transit time and variation of rail cars between plant and factory. The findings and recommendations can be applied across many industries.

This paper focuses on supply chain practices in the chemical industry, which has been slow to adopt supply chain practices. In particular, this paper investigates railcar coordination as one means of enhancing supply chain performance, reducing both inventory and transportation assets.

The purpose of this study is to numerically simulate the Lamb wave propagation through a clamp-on ultrasonic gas flowmeter (UGF) in contact mode, using a new semi three-dimensional approach. Moreover, experimental and analytical modeling results for transit time difference method have been used to confirm the simulation results at different gas flow velocities from 0.3 to 2.4 m/s.

The new semi three-dimensional approach involves the simulation of the flow field of the gas in a three-dimensional model and subsequently the simulation of wave generation, propagation and reception in a two-dimensional (2D) model. Moreover, the analytical model assumes that the wave transitions occur in a 2D mode.

The new approach is a semi three-dimensional approach used in this work, has better accuracy than a complete 2D simulation while maintaining the computing time and costs approximately constant. It is faster and less expensive than a complete 3D simulation and more accurate than a complete 2D simulation. It was concluded that the new approach could be extended to simulate all types of ultrasonic gas and non-gas flowmeters, even under harsh conditions.

In this work, a new approach for the numerical simulation of all types of ultrasonic flowmeters is introduced. It was used for simulation of a Lamb wave ultrasonic flow meter in contact mode.

The purpose of this paper is to propose that transportation modal mix in global supply chains is a result of the strategic alignment between industry characteristics and supply chain strategies.

Using annual US trade statistics and manufacturing industry data for the years 2002-2009 between the USA and its top 12 Asian trading partners, this study applies various regression methods to examine key factors associated with the transport modal decision.

The results show that industry characteristics have an impact on the transportation modal mix in global supply chains. Manufacturing industries use more air freight and less ocean freight when facing positive sales surprises, high-monthly demand variation, a high-contribution margin ratio, a high cost of capital, and increased competition.

The findings provide important insights for logistics managers and freight forwarders. While transportation cost remains an important concern, a logistics manager must also consider non-cost factors such as competition, working capital, and demand uncertainties in their modal decisions. Freight forwarders should be supply chain solution providers who consider all of these industry factors and suggest a proper mix of transportation modes for their customers.

This study is among the first efforts to examine the impact of industry characteristics on the transportation modal mix in global supply chains. This study first develops a theoretical framework for the modal choice decision for international transportation movements and then, using an extensive and innovative data set, provides new findings regarding current air freight practices in global supply chains.

Invasive transit-time ultrasonic flow measurement involves the use of ultrasonic transducers, which sense the flowing fluid and are the most important parts of an ultrasonic flowmeter. In this study, two ultrasonic transducers were designed, numerically simulated and fabricated to be used in an ultrasonic gas flowmeter.

PZT-5H piezoceramic elements with specific dimensions were designed and used as beating heart inside the transducers. Different methods, including impedance-frequency analysis, optical emission spectroscopy and performance tests in pressurized chambers were used to evaluate the piezoelectric elements, ultrasonic transducer housings and the fabricated transducers, respectively. In addition, finite element method results showed its ability for design stages of ultrasonic transducer.

Experimental results for transit time difference (TTD) and the normalized received voltage were compared with simulation results at the same conditions. There was a quite good agreement between the two method results. Extensive simulation results showed that under the considered range of environmental conditions, the change of acoustic path length has the most impact on TTD, with respect to temperature and pressure. A change of 1 mm in acoustic path length leads to 0.74 per cent change in TTD, approximately. In addition, for normalized received voltage, 1 bar change in pressure has the most impact and its value is as high as 3.76 per cent.

This method is possibly used in ultrasonic gas flowmeter fabrication.

In this work, design, fabrication, experimental tests and numerical simulation of ultrasonic transducers are presented.

This paper explores the various alternative routes and methods available to garment exporters in Lao PDR, a land‐locked country in South East Asia, when exporting to the European Union. Lao exporters are dependent on the transport systems in place in neighbouring countries (i.e. Vietnam, Thailand, Malaysia and Singapore) for transit purposes. A multimodal transport cost‐model is used to illustrate and clarify multimodal transport routeing alternatives. A confidence index is also introduced for each route, transport modes and nodal links. Five routeing alternatives are presented in this paper and it is shown that the most frequently utilised route via Bangkok (Thailand) is not necessarily the most competitive in terms of time and cost, while the route via Port Klang (Malaysia) potentially offers a better alternative for Lao garment exporters.

This study aims to examine ship loading strategies during large-scale military deployments. Ships are usually loaded to a stowage goal of about 65% of the ship's capacity. The authors identify how much cargo to load onto ships for each sailing and propose lower stowage goals that could improve the delivery of forces during the deployment.

The authors construct several mixed integer programs to identify optimal ship loading strategies that minimize delivery timelines for notional, but realistic, problem variables. The authors study the relative importance of these variables using experimental designs, regressions, correlations and chi-square tests of the empirical results.

The research specifies the conditions during which ships should be light loaded, i.e. loaded to less than 65% of total capacity. Empirical results show cargo delivered up to 16% faster with a light-loaded strategy compared to fully loaded ships.

This work assumes deterministic sailing times and ship loading times. Also, all timing aspects of the problem are estimated to the nearest natural number of days.

This research provides important new insights about optimal ship loading strategies, which were not previously quantified. More importantly, logistics planners could use these insights to reduce sealift delivery timelines during military deployments.

Most ship routing and scheduling problems minimize costs as the primary goal. This research identifies the situations in which ships transporting military forces should be light loaded, thereby trading efficiency for effectiveness, to enable faster overall delivery of unit equipment to theater seaports.

A physical distribution network can best be analysed and studied as a set of distribution nodes connected chiefly by two kinds of flows: a transportation flow and an informational flow. Co‐ordinating the activities of these two major components is a pre‐requisite for the successful operation of any business enterprise. For unless the company employs its own private carriage, the shipper controls over customer service stops short only at his own dockyard. To be sure, the performance of a transport carrier influences to a large extent the effectiveness of the entire logistics function. For this reason alone, it is not surprising that the selection of an appropriate transport mode and the selection of a given carrier within each mode is indeed an important business decision. Yet, the carrier selection decision has traditionally been characterised by a lack of definitive analysis. In general terms, carrier choices have been based on a combination of rational and emotional motives with emphasis on the latter.

Slow steaming has been implemented by the main liner shipping companies since 2008. The reduction in vessel speed affects fuel consumption and should be reflected within the fuel surcharges paid by shippers. The purpose of this paper is to assess if this was the case for the main outbound European container trades from the port of Antwerp.

Through an extensive analysis of liner service characteristics, fuel costs and fuel surcharges this paper provides an answer to three research questions: how significant are slow steaming practices in container liner shipping?; what is the impact of slow steaming on fuel consumption and liner service characteristics?; and to what extent has slow steaming changed the relation between fuel costs and fuel surcharges imposed on shippers by shipping lines?

It is found that slow steaming practices are not implemented on all trade routes, but depend on operational aspects such as distances covered and the characteristics of the ships deployed. While it could be expected that the reduction in vessel speed should be reflected within the fuel surcharges paid by shippers, the empirical results show that on most trade routes slow steaming did not fundamentally change the relation between fuel costs and fuel surcharges imposed on shippers by shipping lines.

The paper has practical relevance to actors active in global ocean freight logistics, particularly since its results can be used as input for ongoing debates between shipping lines and shippers on pricing and surcharges in container shipping.

This paper is the first extensive study that makes an explicit link between slow steaming practices and fuel surcharge policies of shipping lines. A method was developed to estimate fuel consumption levels of ships at various speeds and to link the associated fuel costs to real‐life bunker surcharges imposed on shippers by shipping lines.

Looks at the development of a new ultrasonic meter for the gas supply industry and explaining the transit time measurement principle on which it works and the performance characteristics of the new meter. Concludes that the ultrasound gas meter could also have medical applications including anaesthetics and hospital ward monitoring. There have been limited production runs of the new gas meter and extensive trials are taking place in several countries.

In a coaxial ultrasonic flow sensor (UFS), wall thickness is a vital parameter of the measurement tube, especially those with small inner diameters. The paper aims to investigate the influence of wall thickness on the transient signal characteristics in an UFS.

First, the problem was researched experimentally using a series of measurement tubes with different wall thicknesses. Second, a finite element method–based model in the time domain was established to validate the experimental results and further discussion. Finally, the plane wave assumption and oblique incident theory were used to analyze the wave propagation in the tube, and an idea of wave packet superposition was proposed to reveal the mechanism of the influence of wall thickness.

Both experimental and simulated results showed that the signal amplitude decreased periodically as the wall thickness increased, and the corresponding waveform varied dramatically. Based on the analysis of wave propagation in the measurement tube, a formula concerning the phase difference between wave packets was derived to characterize the signal variation.

This paper provides a new and explicit explanation of the influence of wall thickness on the transient signal in a co-axial UFS. Both experimental and simulated results were presented, and the mechanism was clearly described.