Aligning the purchase of green logistics practices between shippers and logistics service providers

This paper explores shippers’ (i.e. logistics buyers) and logistics service providers’ (LSPs) perceptions of green concerns under diverse contractual settings during the key phases of the logistics purchasing process: request for proposal, negotiations, contracting and execution. Accordingly, it derives recommendations that could increase the actors’ inter- and- intra-organisational alignment on green targets throughout these phases. Empirical data are obtained from eight individual cases of three shippers and five LSPs, representing the buyer/seller roles within logistics arrangements. Contrary to previous literature holding the view that setting more green demands by shippers would guarantee green outcomes, the findings show that shippers’ green demands may hinder green logistics applications due to impediments to LSPs’ asset-sharing strategies. Also, a deadlock situation is revealed in the negotiations phase, where both actors await each other to introduce additional demands/offers—calling for further regulatory intervention to release this deadlock. Moreover, this paper shows how a mismatch of interests in contractual periods between shippers and LSPs can obstruct green investments—signalling that the green criterion is not the decisive factor in shaping shippers’ outsourcing strategies. The findings also stress a lack of follow-up efforts by shippers on green measures that were specified pre-contract, attributing this to contrasting intra-organisational objectives within shippers’ firms. This paper contributes to the green logistics purchasing literature by revealing how different contractual settings play an important role in shaping shippers’/LSPs’ perceptions of green concerns during the logistics purchasing process. Further, it is one of the first studies to provide phase-specific recommendations to increase the actors’ alignment on green targets.     

Exploring public transport sustainability with neutrosophic logic

Sustainable transportation is a significant component of overall sustainable development. Increasingly, evaluation and decision-making with respect to major complex projects (for example, transportation and land use projects), a multiple attribute perspective is taken. This paper illustrates a multiple attribute decision-making approach for selecting sustainable public transportation systems under uncertainty, that is, with partial or incomplete information represented by single-valued neutrosophic sets (SVNSs). A SVNS is a generalization of a classical set, a fuzzy set, and an intuitionistic fuzzy set. Here, SVNSs and SVNS connectives are illustrated in the context of a ‘Public Transit Sustainable Mobility Analysis Tool’ (PTSMAT) which involves a composite (multiple attribute) sustainability index. A case study of PTSMAT is provided for the UBC Corridor study in Vancouver, Canada. As expected, similar results are obtained to the original study, though the neutrosophic formalism opens a wide range of possibilities for recognition of uncertainty in sustainability assessment.     

Designing optimal autonomous vehicle sharing and reservation systems: A linear programming approach

Autonomous vehicle (AV) technology holds great promise for improving the efficiency of traditional vehicle sharing systems. In this paper, we investigate a new vehicle sharing system using AVs, referred to as autonomous vehicle sharing and reservation (AVSR). In such a system, travelers can request AV trips ahead of time and the AVSR system operator will optimally arrange AV pickup and delivery schedules and AV trip chains based on these requests. A linear programming model is proposed to efficiently solve for optimal solutions for AV trip chains and required fleet size through constructed AVSR networks. Case studies show that AVSR can significantly increase vehicle use rate (VUR) and consequentially reduce vehicle ownership significantly. In the meantime, it is found that the actual vehicle miles traveled (VMT) in AVSR systems is not significantly more than that of conventional taxis, despite inevitable empty hauls for vehicle relocation in AVSR systems. The results imply huge potential benefits from AVSR systems on improving mobility and sustainability of our current transportation systems.     

Exploring low carbon transition pathways for the UK road transport sector

This paper uses an analytical framework of multi-level and multi-phase perspectives to explore low carbon transition pathways for the UK road transport system. The work draws on the impact made by the national (UK) and regional (EU) low carbon policy instruments on the UK road sector. The results show that the transformation pathway, which is at the take-off phase on a large scale, is the only fully active pathway. The transformation is mainly characterized by the adoption of biofuel blends and hybrid electric vehicles, as well as niche technologies. For the emergence of an ideal low carbon road system in the UK, it is shown that the transformation pathway is insufficient and the likely pathway sequence to full decarbonization will be transformation-substitution-de-alignment/re-alignment. However, the dynamics that can favour a smooth process of this sequence will demand a range of active niche technologies and strong government intervention.     

Exploring transportation equity: Development and application of a transportation justice framework

Recent efforts to emphasize social equity in transportation are emerging as local, regional and national governments have set initiatives to identify, existing and potential, disproportionate impacts to low-income and minority populations, also referred to as transportation justice (TJ). Currently, there are suggested methods for identifying transportation justice areas; however, there is no streamlined method instituted across transportation agencies. Each jurisdiction identifies transportation justice (or environmental justice) areas based on their own methodology, typically based on either average regional thresholds, graduated thresholds, or a more unique in-house index methodology. This research explores and evaluates existing methods and develops a rigorous and comprehensive method called the Transportation Justice Threshold Index Framework (TJTIF) using Geographic Information Systems (GIS), as well as factors based on demographics, socio-economics, and transportation/land use. The framework is applied to a case study region in Pennsylvania reflective of the Marcellus Shale impact area, highlighting Sullivan County, PA. The methodology and the case study application serve as an example for how transportation agencies throughout the country can promote social sustainability and enhance transportation equity.     

基于模糊ISM的可持续城市物流发展因素分析

城市物流在现代城市经济发展中占有重要地位。可持续城市物流发展因素已成为了城市物流可持续发展研究首要问题之一。综合可持续城市物流发展的15个因素,运用模糊ISM方法将可持续城市物流发展因素体系构成1个多级递阶模型,并以南昌市可持续城市物流发展为案例进行研究。研究表明：南昌市可持续城市物流发展因素之间关系符合实际情况,所建立的因素结构分析模式可为具有南昌特色的城市物流可持续发展提供指导和借鉴。     

TOD真的需要公共交通吗?——轨道交通可达性以外的重要因素探讨

以公共交通为导向的发展模式(TOD)通常包括在轨道交通车站周边新建住房。引导城市按照这样的模式发展,其目的部分在于减少气候变化、污染以及机动车导致的拥堵。但是,新建住房可能会更容易吸引那些开车较多的富裕家庭,相比房屋所有权和大小、停车供给、街区和分区建筑环境,轨道交通可达性对汽车拥有和使用的影响可能也较弱。通过调查居住在新泽西州北部10个轨道交通车站2英里半径范围内的家庭,收集有关房龄和类型、路外停车位可达性、工作和非工作的出行方式、人口特征以及选择所住街区原因的数据。对调查数据进行地理编码,并与实地调查的路内停车数据、街区和分区建筑环境指标等数据相融合。分析这些因素如何与调查中所记录的汽车拥有和使用情况相关联。住在轨道交通车站附近新房子内的家庭,在汽车拥有、利用汽车通勤以及购物出行频率上明显低于那些住在远离轨道交通的新房子内的家庭。但是,轨道交通可达性在这一差别中起到的作用很小。房屋类型和所有权、局部和分区密度、公共汽车服务、特别是路外及路内停车供给对差异的产生发挥了更重要的作用。     

农业可持续发展探讨

在梳理国内外现有研究成果的基础上，遵照可持续发展理论的要求，探讨了农业可持续发展和农业可持续性的定义，归纳了农业可持续发展的基本特征，并提出了自己的一些认识。     

Global carbon dioxide emissions scenarios for aviation derived from IPCC storylines: A meta-analysis

This research summarises the aviation CO₂ emissions studies that use the Intergovernmental Panel on Climate Change IS92 and Special Report on Emissions Scenarios storylines as GDP growth assumptions to estimate future global carbon dioxide emissions from the aviation sector. The inter-quartile mean and the first and third quartiles are calculated to enable researches studying climate change policies for aviation to use an average global baseline scenario with lower and upper boundaries. We also perform a simple meta-analysis to analyse the assumptions used to derive the baseline scenario and conclude, as expected, that change in revenue-tonne-kilometres and fuel-efficiency are the main drivers behind the baseline scenarios.     

Coming Soon to a Fjord Near You: Future Jellyfish Scenarios in a Changing Climate

Over the last decades, a dense population of the deep-sea/oceanic scyphozoan jellyfish Periphylla periphylla has established itself as top predator in the Trondheimsfjord in Norway, which has caused the traditional fisheries in this fjord to suffer. This was, however, not the first fjord this jellyfish invaded, and data suggest that it will not be the last one, either. With warmer temperatures, the jellyfish is moving northward in Norway, but not all fjords are created equal, and it is not thriving or taking up residence just anywhere. The current article explores three fjords in which Periphylla periphylla has become the top predator and outcompeted former ones. The main question of interest is why the jellyfish becomes dominant in one fjord and not another. The next question is which other Norwegian fjords further north exist with similar characteristics where we therefore would expect Periphylla periphylla to proliferate in the future. The latter is important from a policy and adaptation perspective for the local community of people, since the proliferation of the species unmistakably leads to fewer fish for commercial harvest and potentially less attractive waters for tourism purposes. Results show that three northern fjords, the Skjerstadfjorden the Holandsfjorden, and Stordjupna in the Vestfjord appear to be particularly vulnerable to a future Periphylla periphylla invasion.