Evaluating CO2 emissions, cost, and service quality trade-offs in an urban delivery system case study

Growing pressure to limit greenhouse gas emissions is changing the way businesses operate. This paper presents the trade-offs between cost, service quality (represented by time window guarantees), and emissions of an urban pickup and delivery system under these changing pressures. A model, developed by the authors in ArcGIS, is used to evaluate these trade-offs for a specific case study involving a real fleet with specific operational characteristics. The problem is modeled as an emissions minimization vehicle routing problem with time windows. Analyses of different external policies and internal operational changes provide insight into the impact of these changes on cost, service quality, and emissions. Specific consideration of the influence of time windows, customer density, and vehicle choice are included.The results show a stable relationship between monetary cost and kilograms of CO₂, with each kilogram of CO₂ associated with a $3.50 increase in cost, illustrating the influence of fuel use on both cost and emissions. In addition, customer density and time window length are strongly correlated with monetary cost and kilograms of CO₂ per order. The addition of 80 customers or extending the time window 100 minutes would save approximately $3.50 and 1 kilogram of CO₂ per order. Lastly, the evaluation of four different fleets illustrates significant environmental and monetary gains can be achieved through the use of hybrid vehicles.The results demonstrate there is not a trade-off between CO₂ emissions and cost, but that these two metrics trend together. This suggests the most effective way to encourage fleet operators to limit emissions is to increase the cost of fuel or CO₂ production, as this is consistent with current incentives that exist to reduce cost, and therefore emissions.     

Trust and safety onboard

Shipping is a high-risk industry. The aims of this conceptual paper are to build a framework showing in what way safety onboard is influenced by trust, and to identify the main obstacles to trust-building within the shipping industry. To meet these aims, a literature review and a pilot study are conducted. The study shows that interpersonal trust from employees to managers, and among seafarers, seems to be a prerequisite and an indirect factor, or mediating variable, that influence safety-related organizational outcomes positively and seems to reduce human errors. Interpersonal trust seems to be most valuable in weak situations, which means situations that are not critical and when no exact guidance or incentives to behave in a particular way are needed. An optimal level of trust exists onboard, and because of the high-risk environment, this optimal level of trust is expected to be relatively high. The main obstacles to trust within the shipping industry seem to be the dual employment practice, the physical distance between onboard, crewing agency and onshore, the reduced competence requirements, the frequent reorganization of the crew and multiculturalism. The paper contributes to the trust and to the safety literature by a new framework and to the development of 11 hypotheses on trust and safety. Finally, the paper is indicating that trust may be the missing piece in the safety puzzle.     

Fatigue in transport: a review of exposure,risks, checks and controls*

Human fatigue continues to threaten safe transport. There are claims that employers of operators should do more to mitigate the risks, and several regulators are promoting fatigue-risk management in the context of safety management systems (SMS). The current paper reviews fatigue-related risk and exposure factors and control measures for operators of land- and sea-based transport forms. Our review identifies 13 types of measures for the monitoring or control of fatigue risks: optimal staffing; optimal schedule design; optimisation of breaks/naps; monitoring of actual hours worked; optimisation of work content; monitoring and feedback of actual sleep; health screening and treatment; promotion of recovery from work; fitness-for-duty testing; monitoring of fatigue symptoms while operating; control of fatigue while operating; performance monitoring and assistance; and fatigue-proofing. We also identify two systemic measures needed to anchor risk mitigation in SMS: organisational learning and training/other. By structuring monitoring and control measures along Dawson and McCulloch’s [Managing fatigue: It’s about sleep. Sleep Medicine Reviews, 9(5), 365–380] fatigue-risk trajectory, a framework is obtained that acts as a guide for fatigue-risk management by transport employers. To inform transport managers further, evaluations are needed of the effectiveness of individual control measures as well as whole fatigue-risk management interventions.     

Hailing a change: comparing taxi and ridehail service quality in Los Angeles

Transportation - For decades, taxis have provided for-hire vehicle service without significant competition from other modes. But in 2012, ride-hail services such as Uber and Lyft upended the taxi...     

Demand management of congested public transport systems: a conceptual framework and application using smart card data

Transportation - Transportation demand management, long used to reduce car traffic, is receiving attention among public transport operators as a means to reduce congestion in crowded public...     

Analyzing voter support for California’s local option sales taxes for transportation

Local and regional governments in the U.S. rely increasingly on voter-approved local option sales taxes (LOSTs) to fund transportation capital investments, maintenance, and operations. LOSTs typically present voters with lists of local transportation projects and programs to be funded by a ¼ to 1 percent sales tax increase. Most research on LOSTs are case studies, which make generalizations about LOSTs difficult. We conducted a comprehensive, multi-jurisdictional analysis of LOST measures in California, the U.S. state with the greatest number of LOST measures. We examined 76 LOST measures put to voters between 1976 and 2016 to assess factors associated with voter support. LOSTs in California are enacted by counties, which we examined in addition to smaller intra-county geographies using both regression models and case studies. We tested several explanatory variables for association with voter support including macroeconomic and political context, planned measure expenditures, voter characteristics, and spatial distribution of proposed projects. We found that funding dedicated to public transit and returned to local jurisdictions predicts support at the county level, and that LOSTs that create new taxes—as opposed to extending or renewing existing taxes—are less popular with voters, all else equal. Our analyses of sub-county geographies revealed that political party affiliation is the strongest predictor of local voter support for LOSTs and that voters living adjacent to funded projects tended to be more supportive of LOSTs.

     

Incident reporting in Finnish shipping companies

The purpose of the International Safety Management Code (the ISM Code) is to promote safety culture in the maritime industry. Learning the lessons from incidents should help to improve safety performance since incidents and accidents can share the same root causes. The aim of this paper is to take a closer look at incident reporting in the Finnish shipping industry, to study the reasons for poor incident reporting and to suggest improvements to increase reporting. The paper consists of a literature study, which focuses on previous studies concerning incident reporting, and an interview study, which focuses on Finnish shipping companies and their personnel. The interview study confirmed that incident reporting does not function properly within the Finnish maritime industry. The maritime personnel have an occupational culture which is incompatible with the rule-based safety management approach provided by the ISM Code. The willingness to report incidents could be increased if all seafarers were involved in the reporting process and the preparation of corrective actions. In addition, the reporting procedures should be streamlined and developed to a more user-friendly direction.     

Identification and assessment of aquatic resources for power plant sites on Maryland's Eastern shore

Abstract

A power plant siting procedure which accounts for the protection and preservation of aquatic resources, defined as sensitive life forms and life stages of economically valuable species of finfish and shellfish, is presented as it was executed on Maryland's Eastern Shore. Negative effects of power plant development and operation are generated principally by the cooling water intake and discharge system. The site‐selection procedure is thus presented as a two‐faceted process, termed regional screening, requiring the separate but simultaneous identification of land‐based sites and cooling systems. Criteria included in regional screening for cooling systems reflected life‐sustaining processes essential to the maintenance of aquatic resources. Major sources of effects of power plants on aquatic resources and siting principles as they affect aquatic resources are defined. Information‐gathering techniques included extensive interviews with key research scientists, state personnel, and numerous Chesapeake Bay watermen.     

Employment suburbanisation, reverse commuting and travel behaviour by residents of the central city in the Paris metropolitan area

This paper analyses the relationship between employment suburbanisation in the Paris metropolitan area, the growth of reverse commuting and changes in the weekday travel behaviour of working residents of the central city over a 20-year period. The results show that the number of reverse commuters has significantly increased because the municipality of Paris has lost many jobs but few working residents whilst employment has developed in the suburbs. Reverse commuters are mainly and increasingly high-income professionals whose workplace is located close to the central city in employment sub-centres that are well served by public transport. Consequently reverse commuters have lower than average car use although differences exist and are related to their professional status. The policy implications of these findings are discussed in the conclusion.