4,813 research outputs found
Measuring the Benefits Gained by Industry from Road Network Improvements
Over the last twenty years, physical distribution has gone through a revolution (McKinnon 1989). Changes in industrial structure, the power structure within the supply chain, service quality standards, marketing and production methods, heavy goods vehicle productivity and capacity, and road network quality have all played a part. External factors such as high real interest rates have made firms acutely sensitive to the costs of holding inventory and to the scope for inventory rationalisation. The purpose of this study is to examine the contribution of road network improvement to the restructuring of physical distribution. There is a particular policy context to this. At a political level, the Government attaches prime importance to the effects of road investment on economic growth (DTp 1989). But at the level of economic appraisal, it is questionable whether the Department of Transport's (DoT) procedures give adequate weight to the benefits to industry of road network improvements. The D.o.T. currently take account of the direct savings which accrue from road improvement schemes (Dawson and Vass 1974)(DTp 1981). This allows for changes in mileage related and time related operating costs, including depreciation, based on the simple assumption that time savings are translated fully into proportionate increases in utilisation of vehicles and crews (Nash 1974). Although at first sight, the existence of scheduling indivisibilities and delivery time constraints might be thought to make this assumption unrealistic, such evidence as there is suggests that it is not an unreasonable rule of thumb (Mackie and Simon 1986). Economic theory suggests that in addition to the direct transport cost savings from road improvements, some indirect "reorganisation" or "restructuring" benefits should also be expected (Mohring and Williamson 1969)(Dodgson 1973). As real transport costs fall, firms should respond by substituting within the production and distribution process so as to arrive at a more transport-intensive, but lower cost solution. The restructuring of the brewery industry into an operation with a few large plants is often attributed, at least in part, to improvements in the road network. A number of restructuring responses to strategic road investment may be listed:-
- Centralisation of manufacturing or production
- Concentration of distribution into fewer depots
- Changes to inter-depot boundaries
- Increases in market areas served by regional firms
- Improvements in service quality (24 hour delivery, etc.)
- Changes in distribution methods (e.g. satellite distribution)
This list suggests that the indirect benefits are likely to be some mixture of economies of scale in production or warehousing, inventory savings, and added value to products. A number of studies have been undertaken in the past into the benefits from road network improvements. It is claim they played a part in the decline of road haulage rates between 1974 and 1984 of 27% (Turner 1987). Their effect on transit times and reliability has been demonstrated (Cooper and Tweddle 1988), as well as on the cost of quality of service enhancement (Walker 1988). Benefits gained in terms of larger trading areas have been revealed by studies of the major estuary crossings, such as the Severn and Humber Bridges (Cleary and Thomas 1973) (Mackie and Simon 1986).
Quarmby's studies of a major retail grocery operation are of particular interest in this context (Quarmby 1989). He examines the effect of reducing the number of depots in a distribution system following improvements to the strategic road network so that each depot now serves a larger area. He finds that the total systems benefits from restructuring the distribution and depot network could exceed the direct transport benefits by 30-50%. He does not demonstrate that either his initial or final depot configuration is optimally balanced with the road network conditions. However, his study provided the stimulus for the research proposal to ESRC and to partner industrial sponsors
Transport in the Trans-Pennine Corridor: Present Conditions and Future Options. Interregional Study Working Paper 3.
This paper reports on a desk study carried out by the Institute for Transport Studies as part of a wider study of opportunities for inter-regional working in the trans-Pennine corridor, considering economic, environmental and transport issues. It draws together available information on transport and movement flows in the trans-Pennine corridor. These patterns of movement are examined from a broad perspective which considers intra-regional, inter- regional and international movements within and across the study area. The report proposes a regional package approach to transport, based on demand management and modal transfer
Sellafield-derived anthropogenic C-14 in the marine intertidal environment of the NE Irish Sea
The intertidal biota from Parton beach, close to the Sellafield nuclear fuel reprocessing plant, were all found to be enriched in radiocarbon relative to ambient background. The degree of enrichment appears to reflect the positions of the biota in the food chain once the dilution in seaweed from atmospheric uptake is taken into account. Close to the low-water mark, the order was mussels gt limpets gt anemones congruent to winkles gt seaweed. The same order was observed close to the high-water mark, except that anemones were absent from this area. The activities in the biogeochemical fractions of the water column reflect the fact that discharges are primarily in the form of dissolved inorganic carbon (DIC), which is subsequently transferred to the particulate organic carbon (POC) and, to a lesser extent, the dissolved organic carbon (DOC), and finally, the particulate inorganic carbon (PIC). Analysis of intertidal sediment suggests that there is likely to be a gradual increase in the specific activity of C-14 in the inorganic component of this material as Sellafield contaminated organisms die and their shells are ground down by natural processes
Book Review: A Ministry Renewed: A Ministry Renewed. By HarrisGordon E.. S.C.M. Press, London, 1968. 9s. 6d
Fully anharmonic infrared cascade spectra of polycyclic aromatic hydrocarbons
The infrared (IR) emission of polycyclic aromatic hydrocarbons (PAHs)
permeates our universe; astronomers have detected the IR signatures of PAHs
around many interstellar objects. The IR emission of interstellar PAHs differs
from their emission as seen under conditions on Earth, as they emit through a
collisionless cascade down through their excited vibrational states from high
internal energies. The difficulty in reproducing interstellar conditions in the
laboratory results in a reliance on theoretical techniques. However, the size
and complexity of PAHs requires careful consideration when producing the
theoretical spectra. In this work we outline the theoretical methods necessary
to lead to a fully theoretical IR cascade spectra of PAHs including: an
anharmonic second order vibrational perturbation theory (VPT2) treatment; the
inclusion of Fermi resonances through polyads; and the calculation of
anharmonic temperature band shifts and broadenings (including resonances)
through a Wang--Landau approach. We also suggest a simplified scheme to
calculate vibrational emission spectra that retains the essential
characteristics of the full IR cascade treatment and can directly transform low
temperature absorption spectra in IR cascade spectra. Additionally we show that
past astronomical models were in error in assuming a 15 cm correction
was needed to account for anharmonic emission effects
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Developing Security for E-Commerce Applications: A Teaching Case
The number of severe computer security breaches in e-commerce applications has been on the increase over the last few years. This has become one of the biggest security problems in recent years. Although there are tools to build e-commerce application firewalls to alert and prevent intruder attacks, these tools are not trivial to install (they are not plug-and-play). Internet intruders can create havoc and produce catastrophe results by exploiting weaknesses in e- commerce applications. Therefore, developers of e-commerce web sites have to incorporate ways to systematically identify and eliminate vulnerabilities in the EC applications to enhance their security. This paper describes how Microsoft ASP.Net can be used to assist students in exploring ways to increase the security of EC applications
Enabling Customization through Web Development: An Iterative Study of the Dell Computer Corporation Website
Throughout the last decade, companies have increased their investment in electronic commerce (EC) by developing and implementing Web-based applications on the Internet. This paper describes a class project to develop a customized computer website which is similar to Dell Computer Corporation’s (Dell) website. The objective of this project is to ensure that students receive real-world experiences in the classroom. Students went through three rounds of iterative study and improvements to finalize the project design. This paper presents this customization process using the Microsoft Visual Studio 2005 platform. The paper concludes with a discussion of “lessons learned” and suggestions for effectively teaching project development in an EC design course
Teaching Security Techniques in an E-Commerce Course
Over the past few years, more and more companies have been investing in electronic commerce (EC) by developing and implementing web-based applications on the Internet. While EC can help improve business services and increase customer satisfaction, it also brings increased security risks to those companies implementing it. Developers of EC web sites have to incorporate ways to systematically identify and eliminate security vulnerabilities within their EC applications. This paper describes how Microsoft ASP.Net can be used to assist students in exploring ways to increase the security of EC applications. The hands-on component covers useful techniques for improving application robustness in the pre-sales, online-sales and after-sales phases of an EC application. The paper concludes with a discussion of lessons learned and suggestions for effectively teaching security in an EC design course
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