A multi-objective genetic algorithm approach to design optimal zoning systems for freight transportation planning

This paper contributes to the existing research on freight transportation, spatial and land use planning by investigating an improved spatial aggregation technique to delineate desirable freight traffic analysis zones. Zoning is a process of spatially aggregating several predefined basic spatial units (BSUs) into multiple zones. It plays a vital role in the transportation planning and decision-making process and is well-documented as the modifiable areal unit problem (MAUP). MAUP involves aggregating BSUs to obtain optimal zones satisfying specific criteria and constraints. This paper proposes an improved spatial aggregation methodology to develop a freight traffic analysis zone system by applying the multiobjective optimization concept using a genetic algorithm. The decision variables, namely, (i) Freight trip density; (ii) Number of establishments; (iii) Employment density; and (iv) Compactness, are chosen to represent the elements of freight, passenger traffic, and land use. The problem is formulated as a multiobjective network partitioning problem. The four objectives aim to create zones with better homogeneity and compactness. It is solved using a genetic algorithm with a weighted distance metric approach to prioritize the four objectives. Results show that zones resulting from the improved methodology are superior to the existing zones in terms of homogeneity of decision variables and compactness. The findings are expected to help the decision-making process of urban, transportation, and land-use planners in selecting appropriate freight traffic zone delineation strategies for a given region.     

Urban freight demand forecasting: A mixed quantity/delivery/vehicle-based model

The research germinates from the statement that the cities have to solve the impacts due to freight transport in order to improve their sustainability implementing sets of city logistics measures. But city logistics measures involve several actors and choice dimensions. It is therefore important to have methods and models able to assess the effectiveness of the measures to be implemented. The current models were mainly developed to simulate some aspects of urban freight transport, and are not able to forecast many impacts of implementing traffic and transportation measures at an urban scale.This paper presents a modelling approach that tries to point out the relations existing among city logistics measures, actors and choice dimensions. It comprises three model sub-systems to estimate the quantity O–D matrices by transport service type (e.g. retailer on own account or wholesaler on own account or by carrier), the delivery O–D matrices by delivery time period, and the vehicle O–D matrices according to delivery tour departure time and vehicle type.This modelling system is a multi-stage model and considers a discrete choice approach for each decisional level. It was first tested using some data collected in the inner area of Rome, including traffic counts and interviews with retailers and truck-drivers. The model estimations were also compared with the experimental ones, and quite satisfactory results were obtained.     

Are freight pipelines a pipe dream? A critical review of the UK and European perspective

Freight pipelines represent a novel way for the movement of freight transport and offer an alternative to conventional transport modes. The aim of this paper is to examine the potential for this transport mode within the UK and Europe. Firstly, the latest technological developments are identified, building on the last major review by Howgego and Roe (1998). There is then an analysis of the policy landscape towards freight pipelines, as successful implementation will require the support of policy makers. Finally, some of the major benefits and issues with freight pipelines are highlighted. We conclude that there are still opportunities for the use of freight pipelines, but that further research is yet required to fully understand the supply chain, logistics and other related activities that the introduction of this technology may influence. This is because systems which are presently in commercial operation have exhibited excellent characteristics, although they have not been more widely adopted.     

Localisation of freight consolidation centres serving small road hauliers in a wider urban area: barriers for more efficient freight deliveries in Gothenburg

This paper discusses the negative impacts of freight transport growth, especially in and around urban areas. Over time, a growing number of road freight vehicles have delivered less freight over longer distances, while average load factors have been reduced. This development is unsatisfactory, as transport capacity that could have been used more efficiently is lost. To mitigate negative impact, it has been suggested that freight consolidation and better planned localisation of freight consolidation centres (FCCs) would improve city logistics. Based on primary data, this paper investigates the potential to establish urban FCCs intended for small road hauliers (SRHs) delivering goods to the retail sector in a wider geographical area, the Gothenburg region in Sweden. While the findings show that a large majority of SRHs could reach potential FCC locations in a short time, congestion affects deliveries and several factors, many of which were observed already in the 1970s, restrict FCC establishments. Under present conditions, there is little scope for SRHs to successfully deliver goods to retailers in the Gothenburg region from FCCs; therefore, a more efficient urban transport system from a business or societal perspective is unlikely. Policy makers need to take into consideration the different segments, requirements, and characteristics of different cities before venturing into costly FCC projects.     

Global city regions and the location of logistics activity

The aim of this paper is to extend and develop research surrounding the links between transport and urban regions. An understanding of transport activity has long involved the use of spatial frameworks, seen in the idea of a gateway city (with its surrounding hinterland) and in the identification of hubs or nodes. The particular framework used here is the global city region, a build-out from the much researched global city, and acknowledged as the most prominent feature of spatial development in the global economy. As these areas can accommodate important sea and airport infrastructure, the global city region can be expected to play a significant role in global logistics. Whether that significance extends just from the physical realm, as reflected in the infrastructure, or whether it is embedded in the scale and complexity of the advanced business services sector within the global city, is the issue that lies at the heart of the research. The research has set out to answer the question: “How important are these regions in logistics activity?”. The question has relevance in the context of transport geography as it provides an urban structure perspective on what is commonly seen as separate port or airport activity. Its relevance is enhanced as its answer relies upon a simultaneous analysis of both sea and air freight activity. Results show these regions counted for a substantial and growing share of sea and air freight between 1996 and 2006. In accounting for that outcome the research explores the particular effect of infrastructure (showing that global city regions with multiple seaport and airports play a special role) and also isolates the links with global city functions. The paper concludes with some insight on the special challenge these places create for strategic urban planning policy.     

Zonal method for urban travel surveys: sustainability and sample distance from the CBD

This paper details a method of surveying the travel behaviour and values of households within inner, middle and outer urban zones. This survey of 400 households in two North Queensland (Australia) cities provides details of 3500 urban trips, travel modes and choices linked to household location. Stratified sampling based on distance from the Central Business District shows pronounced methodological advantages. This simple and effective method shows that outer urban dwellers used about three times the amount of fuel as their more central counterparts, placing them at the vanguard of unsustainable urban travel, a great challenge for policy, developers and city planners.     

Urban spatial structure,employment subcenters,and freight travel

Metropolitan areas in the U.S. have become increasingly polycentric. Large employment subcenters have emerged outside of central cities, competing against the traditional city center for labor and businesses. The existing literature on land use and transportation focuses on passenger travel, providing little insight into the impact of polycentric metropolitan development patterns on freight activity. In this study, we use the Los Angeles region as a case study to examine the relationship between urban spatial development patterns and freight travel. Using the National Employment Time Series (NETS) data, we identify employment subcenters in metropolitan Los Angeles. We characterize freight activities associated with the subcenters using data from the Southern California Association of Governments (SCAG). We develop a regression model that estimates freight activity as a function of geographic characteristics, such as whether a location is in an employment subcenter, measures of nearby employment, access to the highway network, and proximity to intermodal freight facilities. The results indicate that employment is an important driver of freight activity; however, employment subcenters have an independent effect on freight activity. The results of this study suggest that further research on urban spatial structure and freight activity should assess the effects of employment subcenters and how their particular employment composition and characteristics are associated with freight activities at the metropolitan level. Such an approach would lead to more precise policy recommendations for urban goods movement.     

Urban growth and freight transport: From sprawl to distension

This paper aims at discussing the effects of the urban growth on freight mobility through the analysis of urban activities localisation. Thanks to the results of this work, we lay the basics of an original concept that synthetizes logistics sprawl and other localisation dynamics taking into principal consideration the mobility of freight in general: the logistics distension.Through the spatial analysis of activities and population localisation between 1982 and 2012 in Lyon's urban area, we show the evolution of the socio-economic morphology and evolution of the freight landscape. Through freight movements modelling, we show the evolution of freight mobility in the conurbation of Lyon with regard to the modifications of the urban fabric.     

An ex ante evaluation of mobile depots in cities: A sustainability perspective

Today, a large share of cost, congestion, and emission in cities is attributed to light goods vehicles like carrier vans distributing to the last mile. The aim of many policy agendas is to reach cleaner cities with less disturbance from the distribution vehicles. Several suggestions have been put forward and tested in research and practice, such as access restrictions, multimodal transport, and use of cleaner vehicles. In this paper, we develop a case for a more sustainable freight distribution within cities using an ex ante case study. The idea of the mobile depot is built on the iteration between historical transitions within cities and contemporary developments in urban freight distribution, and then analyzed ex ante both quantitatively in calculations and qualitatively in two stakeholder workshops. The idea is integrated and multimodal, based on a mobile depot (e.g., a bus, truck, barge, or tram) that circles the city and connects to low emission last mile delivery options such as LEVs (Light Electrical Vehicles) or cargo bikes. We found that such a system can be environmentally and socially better for the city context, while maintaining economic viability above a certain utilization rate of the mobile depot for the transport operators.     

Improving the design of urban loading zone systems

Despite the ubiquity of loading zones in most commercially dense streets of medium and large cities, there exists no generally acknowledged procedure to establish their number, location and management system. We propose a methodology divided in two steps, where the first one estimates the required number of loading zones on a given street and the second one locates them taking into account the delivery characteristics of the retail establishments they will be serving. The application of the methodology is tested in four streets in the Spanish city of Seville, following a retailer survey to collect all the relevant data. The results provided by the application in terms of number and location of loading zones are simulated together with other scenarios with different numbers of loading zones, and the outcomes are compared with the existing situation. The new methodology results in an improvement in the level of service provided with a similar – or smaller – number of loading zones, but most importantly causes a significant reduction in the distances between loading zone parking spaces and final destinations.     

Estimation of traffic density from drone-based delivery in very low level urban airspace

Driven by rising consumer demand, interest is growing in the application of autonomous unmanned aerial vehicles (drones) for the last-mile delivery of small express packages and fast-food meals in cities. To be realised, this would require the Very Low Level (VLL) urban airspace to be able to cope with high traffic densities of commercial delivery drones. The potential benefits of such novel drone-based applications are a reduction of traffic congestion in cities, lower greenhouse gas emissions and more efficient transportation operations. To help realise this concept, programs such as U-Space, the unmanned traffic management system for Europe, are developing important services such as deconfliction management and dynamic capacity management. However, for several of these services, design choices will depend on how, and how extensive they will be used. It therefore becomes important to estimate how many delivery drones would operate in a typical city. This paper aims to provide an estimate by establishing a framework to determine the traffic demand for express drone-based package delivery of five European countries. In addition, a detailed case-study is presented for determining traffic density of express package drone delivery for Paris metropolitan area in order to assess the feasibility from a user's perspective. The paper also discusses the potential of fast-food meal delivery drones compared to traditional delivery modes for Paris. Results suggest that hourly traffic densities culminating from express package and fast-food meal delivery drones will exceed today's global commercial aircraft traffic of 10,000 per day by more than six-fold for just one potential metropolitan city.     

Assessment of the socio-spatial effects of urban transport investment using Google Maps API

We analyze the spatially distributed impacts of transport investment in urban highways and public transport with a novel methodology based on the capabilities of online technology to replicate the (unobserved) condition without highways. This is based upon the intensive use of Google Maps API (GMA) to obtain travel times between each origin-destination pair at a highly detailed level to reveal the effects of new infrastructure on different zones and groups within a city. Santiago is used as a case study, as the city introduced 150 km of urban highways, a reorganization of surface transit, and new subway lines in a relatively short period. We show that the high-income segment of the population has been the most favored, simultaneously increasing the difference between transit and car travel times in those areas where car ownership is low, stimulating the acquisition of a car.     

Regional disparity analysis of Chinese freight transport CO2 emissions from 1990 to 2007: Driving forces and policy challenges

Freight transportation and logistics act as the artery of the national economy. With a booming economy, China's freight transport sector has experienced dramatic growth in recent decades and has become a key driving force of China's CO₂ emissions. Therefore, effective and efficient mitigation policies in the freight transport sector are critical for China to promote CO₂ emission mitigation strategies. In contrast to other countries, China's challenge stems not only from technical issues but also from regional socioeconomic disparities, which in turn require the implementation of locally oriented policies. For this reason, an analysis based on regional disparity is of vital importance for future policy making. However, to date, there have been few pertinent studies on the freight transportation sector. To fill this gap, this paper aims to conduct an in-depth comparative study of CO₂ emission characteristics and the driving forces in the freight transport sector in China's three regions (covering 31 provinces) from 1990 to 2007. The log mean Divisia index method (LMDI) is employed to analyse the driving forces, and the Gini coefficient is used to investigate regional inequity. Additionally, regional disparity is explored in-depth based on the analytical results and practical concerns. The results highlight that economic structure is a key driving force for emissions change and reveal significant regional disparity and inequity in freight transport emissions. The results are critical for future policy-making to address regional concerns.     

An urban consolidation center in the city of Copenhagen: A simulation study

Urban consolidation centers (UCCs) have a key role in many initiatives in urban logistics, yet few of them are successful in the long run. The high costs often prevent attracting a sufficient number of UCC users. In this paper, we study sustainable business models and the supporting role of administrative policies. We perform an agent-based simulation applied to the city of Copenhagen and collect data from a variety of sources to model the agents. Both the data and case setup are validated by means of expert interviews. We test 1,458 schemes that combine several administrative measures and cost settings. Most schemes yield significant environmental benefits; many of them reduce the truck kilometers driven by about 65% and emissions by about 70%. The key challenge is to identify schemes that are also financially sustainable. We show the importance of committing carriers to the UCC as soon as possible, as carriers potentially generate the bulk of the revenue. Subsequent revenues may be generated by offering value-adding services to receivers. Based on the numerical experiments, we pose various propositions that aid in providing favorable conditions for a UCC, improving its chances of long-term success.     

城市交通发展对铁路货运站布局影响的研究

城市区域结构和产业布局的调整、城市规划理念的变化,使铁路货运站的位置需重新确定。城市轨道交通形成网络后,市内运输能力大大提高,铁路枢纽所有为城市服务的设备和设施均可移出市区,城市内的货物运输可由城市轨道交通系统利用凌晨时段完成。为此,提出了铁路枢纽内货运站设置的数量、位置,以及城市内货运集散点位置的确定方法。     

Evaluation of the spatial pattern of logistics facilities using urban logistics land-use and traffic simulator

Despite the growing research interests on the spatial restructuring of logistics facilities that occurred in many cities around the world, the relationship between the spatial pattern of logistics land use and the level of externalities is far from being elucidated. We use the Urban Logistics Land-use and Traffic Simulator (ULLTRA-SIM), developed for the Tokyo Metropolitan Area, to evaluate the level of externalities that accompany different spatial distribution patterns of logistics facilities. The ULLTRA-SIM takes a novel approach to analyze the urban freight impacts through the simulations of logistics facility locations, urban logistics chains, and truck flow. The results indicate that, while the moderate concentration and deconcentration of logistics facilities do not significantly affect the level of externalities, scarcity of logistics facilities in or near the high demand locations exacerbates negative externalities. Also, the results of the simulations underscore the need for rigorous analysis in order to reduce negative externalities through logistics land use policies.     

How do the effects of local built environment on household vehicle kilometers traveled vary across urban structural zones?

Many studies have examined the effects of the local built environment (LBE) on household car usage. However, it remains unclear how these effects vary across urban structural zones. This study examines the case of Shenzhen and employs a multigroup structural equation model to reveal the varying LBE effects among car-owning households in inner-city, inner-suburban, and outer-suburban zones. The empirical modeling results indicate that the distance from the residence to the city center and the work-home distance have the greatest influence on household vehicle kilometers traveled (VKT). Average household VKT decreases with the distance from the residence to the city center after it peaks at the threshold radius distance of 8–10 km to the city center. In general, dense, mixed, small-block land use patterns reduce household VKT. However, the magnitude and significance of the LBE effects on household VKT vary across urban structural zones. These findings suggest that land-use policies can be developed specifically for different urban structural zones to effectively decrease household VKT.     

Freight village evaluation under uncertainty with public and private financing

The paper presents a method and models for assessing the financial viability of a new Freight village financed by private and public investments. The financial evaluation model constitutes an integrated part of a wider planning methodology, with four distinct phases, namely (a) site selection and traffic forecasts, (b) definition of services offered and corresponding dimensions, (c) estimation of investment and operation costs and (d) evaluation of investments. The paper presents the overall methodology, and presents analytically the evaluation method with the corresponding model. The model is developed specifically for the financial evaluation of investments for a Freight village incorporating uncertainty considerations in the values of the variables considered. The financial evaluation method identifies the various transport and other variables, which determine the cash flow of inputs (revenues) and outputs (investments, expenses) related to the construction and operation of a Freight village. Furthermore, the model produces financing scenarios, based on combinations of public and private funds as well as bank loans. In addition using Monte Carlo simulation the expected values of some key variables (investment costs, forecasted volumes and revenues) are estimated. Finally using linear programming an optimization related to the amount of private funds invested for a specific Freight village can be determined related to a mix of public and private funds (under certain constraints). An application of developed methodology and models is done for the case of a Freight village in Northern Greece, demonstrating its potential to application for similar cases.     

Logistics land use patterns in metropolitan Canada

This paper focuses on the spatial patterns of freight and logistics activities in Metropolitan Canada. The literature acknowledges that these activities, while fundamentally important to economic and social wellbeing in cities, also contribute negatively to aspects of urban life through their associated vehicular traffic for example. The at times sprawling nature of their pattern (Dablanc, Ogilvie, & Goodchild, 2014; Dablanc & Ross, 2012), driven by industry desires for larger footprints, can further exacerbate these negatives. However, the existence of sprawl is not common in all major centres, with local variations in influencing factors interacting with systematic developments in the logistics industry (e.g. larger facilities). The objectives of this paper are to analyse the pattern of logistics developments in Canadian cities and to explore the factors influencing the observed patterns. The methodology employs a case study approach (building on the authors previous work on the Greater Toronto Area - (Woudsma, Jakubicek, & Dablanc, 2015), obtaining fine-grained spatial data on logistics businesses and their employment levels across selected Canadian cities including Vancouver, Calgary, Montreal, Winnipeg and Halifax. The data used to assess these patterns were business listings from DMTI spatial, a Canadian provider of geospatial data. The data set used in this paper contains listings of business names, addresses, SIC codes in 2002, and NAICS and SIC codes in 2012. For analysis of this data, our approach uses basic spatial indicators, like mean centre of establishments and average distance to mean centre, along with statistical analysis of facility types and intra-regional changes. The exploration of influencing factors is conducted through in-depth review of industry publications, regional news sources, and conversations with experts in the commercial development industry in each case study city. Preliminary results indicate that in smaller metropolitan areas (Winnipeg, Halifax), the land supply pressures, and scope of logistics developments result in no evidence of sprawl. In the remaining cities, there is moderate evidence of sprawl, with noted influences including supply and local development controls. These results are discussed in the context of the current literature on urban logistics sprawl with directions for future work provided.     

Supply chain micro-communities in urban areas

An increase in urban freight transport is inevitable as growing urban populations require more goods, more conveniently. A deeper understanding of the geography and trends of urban freight transport must recognise that it is the aggregate result of a complex web of supply chain interactions. To understand the trends, the behaviour of the underlying supply chains must be understood. Using Global Positioning System (GPS) traces of commercial vehicles and network theory concepts, this paper examines the characteristics of supply chain micro-communities in three urban areas in South Africa. The similarity in the structure of these micro-communities across the three, very diverse, areas suggests that the dynamics that drive supply chain interaction are not dependent on local geography. Four prominent archetypes were identified that account for more than half of the micro-communities in each area. Directionality, geographic dispersion and the balance of importance in the micro-communities are studied in the context of these archetypes. This paper presents a first puzzle piece in deducing urban freight transport patterns from supply chain interaction. Furthermore the results are an empirical benchmark that can validate theoretic models of urban supply chain interaction.