Short Hauls Research Articles

Telematics and machine learning system for estimating the load condition of a heavy-duty vehicle

This study employs machine learning techniques to determine whether trucks are loaded or empty based solely on data from the vehicle's communication network, especially from the engine module. We achieved an accuracy of over 85% for short hauls (0.5 to 5 km) and nearly 95% for long hauls (5 to 500 km). This approach not only streamlines fleet management, reducing the need for communication between managers and drivers but also plays a crucial role in research related to fuel consumption reduction and intelligent fault diagnostics. Minimizing dependence on imprecise and time-delayed human responses opens new avenues for effective studies and innovative solutions in the transportation industry.

Electric Two-Wheelers: The Future of Short Hauls

Electric Two-Wheelers: The Future of Short Hauls

Design Evolution and Wind Tunnel Tests of a Three-Lifting Surface Regional Transport Aircraft

This paper deals with the experimental assessment of the aerodynamic characteristics of an innovative large turboprop aircraft. The configuration is a three-lifting surfaces airplane with rear engine installation at tail tips, conceived to carry up to 130 passengers and targeting a minimum economic and environmental impact, which is competitive with regional jets on short and medium hauls. The three-lifting surfaces layout is the output of previous research made by the authors, and it has been selected to fully comply with the market and design constraints. An experimental test campaign was required to validate the aerodynamics, stability, and control of this innovative configuration. From the results of the first campaign, it appeared that the aircraft had insufficient longitudinal and directional stability. Thus, the authors worked to improve these characteristics, updating the design and executing a second wind tunnel test campaign. The evolution of the design is described in the first part of the paper. In the second part, the authors discuss the aerodynamic interference effects among aircraft components, detailing how the combined downwash coming from both the canard and wing, as well as their wakes, affects the empennage aerodynamics. Experimental tests have revealed a significant reduction of the longitudinal stability due to canard additional downwash, especially at low attitudes. Furthermore, it was found that the canard generates a non-linearity on the aircraft directional stability derivative at moderate sideslip angles because of its tip vortex impinging on the vertical tail. Despite the detrimental interference due to the canard, the updated aircraft proved to be statically stable with sufficient margin at the most rearward center of gravity. Lessons learned in this research may be useful to aerodynamicists and aircraft designers facing similar issues.

Next Generation of High-Speed Optical Communications Networks Using OFDM Technology

The usage of data transmission through Optical Fiber is highly preferred in every area where transferring of data is needed from one end to another. Moreover, nowadays the infrastructure of telecommunications is in good shape and size to handle data transmission through its optical fibers which have low attenuation and higher bandwidth. The seeking of data rate higher than 100Gbit/second and above has been increased to build it in urban and rural areas, and for long and short hauls. Consequently, the current goal is to propel this transmission system into the next appropriated level to avoid any decline of the optical infrastructure than its current capacity. To fulfill increased demand for bandwidth in Broadband services one of the most trusted technology is the Orthogonal Frequency Division Multiplexing (OFDM). The Orthogonal Frequency Division Multiplexing has been placed on-demand in optical communication, it is used in Long haul transmission Format in Direct and Coherent detection. OFDM has many features and abilities can boost the optical fiber performance by eliminating several limits of conventional Optical Fiber communication. OFDMA has polarization mode dispersion (PMD) and chromatic dispersion (CD) which are considered a big addition to the current systems. In addition to that, the easy correlation of the coherent optical OFDM with Wavelength Division Multiplexing (WDM) systems can further advantages in the transmission system such as super bandwidth, high spectral efficiency, and extra data rates. Furthermore, the WDM systems can improve data rate and capacity by using multiple wavelengths over a single fiber. This work aims to bring implementation and to perform a deep-dive study of higher data rates using Direct and Coherent Optical OFDM for long path transmissions. This research starts with a unique user and then extends to the add the OFDM - WDM system to get a data rate of 100 Gbps. Regarding the software portion, the Optisystem simulation tool was used for the design and implementation of the system. Moreover, the modulation type used is QAM for the OFDM signal, and I/Q modulation is deployed, while Coherent and Direct detection is used at the receiving portion. Q Factor, the bit error rate and eye diagram were discussed to study the System’s Performance and Quality. This work found CD-OOFDM is the best system for next generation of optical. The work compared WDM CD-OOFDM with SMF-DCF to DD and CD-OOFDM. In addition to that, it compared WDM CD-OOFDM with SMF-DCF to CD-OODFM with SMF. Therefore, the results showed that WDM CD-OOFDM with SMF-DCF achieved 25 Gbps for four channels of the WDM system at 120km channel, where the carrier frequencies were from 193.05THz to 193.2THz.

Willingness to pay for airlines’ premium economy class: The perspective of passengers

This study investigates how much extra air travellers are willing to pay to upgrade to premium economy class by using a suitable econometric model. Since a large portion of travellers' willingness to pay for premium economy class is zero, the spike model is applied to overcome the issues that may occur when traditional statistical models are used. Three flight distances, short, medium, and long hauls were separately estimated to investigate the effects of flight distance on willingness to pay. Travellers’ willingness to pay to upgrade from economy class to premium economy class round-trip was US$138 ,1 US$309, and US$545 for short-, medium-, and long-haul, respectively. The research results should be a helpful reference for the civil aviation industry in strategic pricing planning.

Energy is Key to Shape of Commercial Flights in the Future

Compared to military flight, speed, maneuverability, and stealth are not of foremost importance in consideration for commercial flights planned for the future. Increased laminar flow over the wings, a power source that is renewable and affordable, together with greater passenger safety, seems to be the top design considerations. Manned solar flight, which has already been demonstrated for short hauls, has already succeeded. The success and future of solar-powered flight for the flying public depends on research and development in this area. The inspiration from flight record breakers like Steve Fossett and solar-powered flight pioneers like Piccard and Borschberg should not be underestimated. They have put mechanical and aerospace engineers again at the forefront of the aircraft industry.

En Route Speed Reduction Concept for Absorbing Air Traffic Flow Management Delays

This paper proposes an en route speed reduction to complement current ground delay practices in air traffic flow management. Given a nominal cruise speed, there exists a bounded range of speeds that allows aircraft to fly slower with the same or lower fuel consumption than the nominal flight. Therefore, flight times are increased and delay can be partially performed in the air, at no extra fuel cost for the operator. This concept has been analyzed in an initial feasibility study, computing the maximum amount of delay that can be performed in the air in some representative flights. The impact on fuel consumption has been analyzed, and two scenarios are proposed: the flight fuel remains the same as in the nominal flight, and some extra fuel allowance is permitted in order to face uncertainties. Results show significant values of airborne delay that may be useful in many situations, with the exception of short hauls where airborne delay may be too short. If cruise altitude is changed, the amount of airborne delay increases, since changes in cruise speed modify the optimal flight altitudes. From the analyzed flights, a linear dependency is found relating the airborne delay with the amount of extra fuel allowance.

A comparative study of truck cycle time prediction methods in open‐pit mining

PurposeThe purpose of this paper is to compare the predictive capability of three methods of truck cycle time estimation in open‐pit mining: computer simulation, artificial neural networks (NNs), and multiple regressions (MRs). The aim is to determine the best method. The most common method currently used is computer simulation.Design/methodology/approachTruck cycle times at a large open pit mine are estimated using computer simulation, artificial NNs, and MRs. The estimated cycle times by each method are in turn compared to the actual cycle times recorded by a computerized mine monitoring system at the same mine. The errors associated with each method relative to the actual cycle times are documented and form the basis for comparing the three methods.FindingsThe paper clearly indicates that computer simulation methods used in predicting truck cycle times in open‐pit mining underestimate and overestimate the results for short and long hauls, respectively. It appears that both NN and regression models are superior in their predictive abilities compared to computer simulations.Research limitations/implicationsThe cycle time prediction models developed apply to a specific mine site and one has to be careful not to directly apply these models to other operations.Practical implicationsThe paper describes the implementation of regression and NN modelling. An opportunity exists for mines to utilise the large volumes of data generated to predict truck haulage cycle times more accurately and hence, improve the quality of mine planning.Originality/valueThe paper addresses an area of need in the mining industry. Accurate prediction of cycle times is critical to mine planners as it impacts on production targets and hence, the budgets.

The Use of Dog Sledges during the British Search for the Missing Franklin Expedition in the North American Arctic Islands, 1848–59

While the bulk of the searching parties sent out from the British ships deployed on the search for the missing Franklin expedition in the North American Arctic Islands over the period 1848–59 employed man-hauled sledges, dog sledges were also used quite extensively. The dog sledges were especially (but not exclusively) used as “couriers,” that is, for communication between the various wintering ships, where speed was the primary requirement. The total distance covered by dog sledges (excluding short hauls in the vicinity of the wintering ships) was, at a minimum, 11 576 km; this distance compares with the minimum 41 555 km covered by man-hauled sledges.

Logistics Network of Export-Import Textile Products in the Daegu-Kyungbuk Area

In the production of textiles, there exist various inter-firm manufacturing processes. By the reason, it is inevitable to restructure logistics process to enhance the competitiveness of the textile industry in Daegu-Kyungbuk area. The Yeong-Nam inland clearance depot(ICD), which will be open in the year of 2010, can be utilized as an alternative to increase the efficiency of logistics process for textile industry. Logistics network can be simplified and reduce inter-firm short hauls by concentrating logistics activities on the Yeoun-Nam ICD. Furthermore, the establishment of distribution warehouse for the textile industry in the Yeong-Nam ICD should be considered to enhance logistics efficiency.

Temperature Sequence of Eggs from Oviposition Through Distribution: Transportation—Part 3

The Egg Safety Action Plan released in 1999 raised many questions concerning egg temperature used in the risk assessment model. Therefore, a national study by researchers in California, Connecticut, Georgia, Iowa, Illinois, North Carolina, Pennsylvania, and Texas was initiated to determine the internal and external temperature sequence of eggs from oviposition through distribution. Researchers gathered data from commercial egg production, processing, and distribution facilities. The experimental design was a mixed model with random effects for season and a fixed effect for duration of the transport period (long or short haul). It was determined that processors used refrigerated transport trucks (REFER) as short-term storage (STS) in both the winter and summer. Therefore, this summary of data obtained from REFER also examines the impact of their use as STS. Egg temperature data were recorded for specific loads of eggs during transport to point of resale or distribution to retailers. To standardize data comparisons between loads, they were segregated between long and short hauls. The summer egg temperatures were higher in the STS and during delivery. Egg temperature was not significantly reduced during the STS phase. Egg temperature decreases were less (P < 0.0001) during short delivery hauls 0.6°C than during long hauls 7.8°C. There was a significant season × delivery interaction (P < 0.05) for the change in the temperature differences between the egg and ambient temperature indicated as the cooling potential. This indicated that the ambient temperature during long winter deliveries had the potential to increase egg temperature. The REFER used as STS did not appreciably reduce internal egg temperature. These data suggest that the season of year affects the temperature of eggs during transport. Eggs are appreciably cooled on the truck, during the delivery phase, which was contrary to the original supposition that egg temperatures would remain static during refrigerated transport. These data indicate that refrigerated transport should be a component in future assessments of egg safety.

Overview of coupling noise prediction for turbofans with engine and aircraft performance

In this work, a comparison of the noise levels of different aero-engines is presented. The coupling is based on integrating a gas turbine design and performance model with an aircraft model for long and short hauls and a noise model made of established empirical methods available in the open literature for turbofan noise prediction at design and off-design points. After joining together the performance models with the noise methods, the authors have studied three ultra high bypass ratio engine configurations vis-à-vis their baseline counterpart of equivalent thrust rating. Also, the effect of application of passive noise attenuators (liners) to reduce the noise is explored. The results obtained showed that though there are derivable benefits from the ultra high bypass ratio turbofans, such as reduction in fuel consumption, in jet noise and reduction of broadband noise for the fan, the new engines generate higher noise at lower frequencies in the fan.

EU network carriers, low cost carriers and consumer behaviour: A Delphi study of future trends

Abstract This paper uses a Delphi panel of 26 air transport experts to forecast the structure of air transport in the EU in 2015 in respect of network carriers, low cost airlines and passenger behaviour. Secondary research was used to construct a number of scenarios about the future structure and strategy of EU network and low cost airlines and also traveller behaviour. Consensus of opinions was sought amongst the panel in a two-round process. The consensus opinion of the Delphi experts was that; network carrier consolidation will reduce EU players to less than five, there will be only two or three large low cost carriers, Business Class products will disappear on short hauls, and leisure travellers will take an increasing number of multiple short-duration holidays.

A comparison of methods for estimating relative abundances in bottom longline fishery surveys

Longlines lose fishing power with soaking time due to bait losses and hooked fishes. Because logbook records and dockside interviews usually do not include detailed data on fishing power loss, relative densities in commercial fishing are estimated as the number or weight of fishes caught per hook and unit of time. To investigate the influence of the fishing power loss of bottom longlines on relative density estimates, data of 188 standardized hauls of 1000 hooks, baited with squid and soaked for 3 h in average were analyzed. The estimates given by the number of fish caught per 1000-hook-hour (CPUE) were compared to those from the partial removal instantaneous rates ( λ) caused by each species, an index that requires detailed information that takes into account the progressive decrease in the number of baited hooks available to fish. It was found that, for relatively short hauls observed in commercial fishing operations in Southern Brazil, the patterns of bathymetric and latitudinal distribution of the three most numerous species in the catch did not differ significantly when calculated in either units. Nevertheless, high initial catch rates resulted in lower correlation between both measures. It was concluded that the analysis of CPUE from bottom longline commercial fishing catches can result in reliable information on the distribution and relative abundance of the target species in the fishery.

The role of the generally unrecognised microprey source as food for larval fish in the Irish Sea

Few studies have studied the food supply to larval fish in the Irish Sea; thus, we have assessed the full prey-field available to larval fish, ranging from protozoa to copepods. Specifically we assessed if fish larvae feed on protozoa, as suggested by others, and if densities of the protozoa and the appropriate size of metazoan prey were previously underestimated. By examining the gutcontents of fish larvae, the prey available to them, and the potential accessibility of prey to fish, we develop a simple food web, presented as a box-model. By doing so, we indicate that the lack of focus on small metazoa and protozoa has underestimated the food available to fish larvae; without these, we might have concluded that prey levels were too low to support the growth of the larval fish assemblage. Our methods were as follows. Sampling was at two sites, off the Isle of Man, with distinct physical and biological structures, soon after fish spawning: the southwest coast, where many species occur in spring-summer (23 April; 6, 19 May; 1, 22 June; 12 July) and the east coast, where only herring larvae occur in September–November (12, 28 October). Microplankton (15–200 μm), mesozooplankton, and larval fish were collected at 1, 15, and 25 m: microplankton with 1.5 L bottles and a 64 μm-mesh net; mesozooplankton and larval fish with a Gulf VII high-speed sampler (280 μm mesh). The 64 μm mesh net, mounted on the Gulf VII, provided simultaneous hauls. Fixed samples were evaluated to determine species composition, abundance, and biomass. Larval fish diet was determined from fish collected by short net hauls: fixed guts were examined and prey, including protozoa, analysed. Using physical data as a guide, plankton data were integrated through the water column to determine standing stocks. Size-based food availability to larval fish was estimated from the gut contents. The role of protozoa was examined, assuming that they are digested at the same rate as metazoan and if they are digested 2.5–10 times faster; increased digestion rates indicated that they contributed substantially to the larval fish diet.

Developing Reservation Economies: Native American Teamsters, 1857–1921

The Act of March 1, 1877 (19 U. S. Stats. 291), accorded American Indian entrepreneurs the right to transport almost all freight shipped by the Indian Department to Indian agencies, reservations, agency schools and Indian Department hospitals. American Indian teamsters, stevedores and seamen who had worked in these capacities for decades, adopted the Act as their own. Native Americans moved millions of pounds of freight from ships, docks, overland, and over long and short hauls for government contractors, federal Indian agencies, Indian traders, and the military and for private individuals. The entrepreneurs were essential to logging, fishing and whaling, home building, lumber industries, haying and farming, milling, and building and maintaining Indian agency infrastructures, schools, local communities and military posts. American Indians managed ponies, horses, oxen and mules, captained sailing schooners and contracted seagoing canoes, and traversed climatic and topographical challenges as they carved their places in the history of Indian Country.

SOME METHODS OF IMPROVING FREIGHT TRANSPORTATION IN SHORT HAULS

The results obtained in the investigation aimed to improve the transportation of commercial freight for short hauls in the city are presented. The performed tasks included the statistical analysis of freight flows; the forecast of the freight flows; a synthesis of a topological stmcture of the urban system of freight transportation and the description of the optimal structure of the truck stock. The conclusions have also been drawn and some recommendations provided.

Contractual Form and Market Thickness in Trucking

A central proposition of the transaction costs literature is that firms will substitute more complicated contractual arrangements for simple spot arrangements when transactions involve relationship-specific investments. I investigate this proposition by testing whether simple spot arrangements are less common when local trucking markets are thin. I find that doubling the thickness of the market increases the likelihood that simple spot arrangements govern transactions by about 30% for long hauls. I find weaker evidence of relationships between local market thickness and contractual form for short hauls—hauls for which quasi-rents are particularly small. Contracts protect quasi-rents over a surprisingly large range, but they play a less important role as quasi-rents decrease.

Contractibility and Asset Ownership: On-Board Computers and Governance in U. S. Trucking

We investigate how contractual incompleteness affects asset ownership in trucking by examining cross-sectional patterns in truck ownership and how truck ownership has changed with the diffusion of on-board computers (OBCs). We find that driver ownership of trucks is greater for long than short hauls, and when hauls require equipment for which demands are unidirectional rather than bidirectional. We then find that driver ownership decreases with OBC adoption, particularly for longer hauls. These results are consistent with the hypothesis that truck ownership reflects trade-offs between driving incentives and bargaining costs, and indicate that improvements in the contracting environment have led to less independent contracting and larger firms.

How Wide Is the Scope of Hold-Up-Based Theories of Governance? Shipper-Carrier Relationships in Trucking

Previous researchers have established that hold-up-based theories of governance (Klein, Crawford, and Alchian (1978), Williamson (1979, 1985)) can have predictive power. The scope of their predictive power is an outstanding empirical issue. I investigate this in the context of trucking. The nature and degree of relationship-specific investments differs for short and long hauls. I find that long-term contracts are used more relative to spot arrangements when local markets are thin for long hauls, but not short hauls. For long hauls, the relationship between governance and local market conditions is strongest in states in which inbound markets are thin. The predictive scope of the theories extends beyond circumstances where investments are large and sunk over long horizons, but not to those where quasi-rents are small and appear only in the very short run.