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The handmade bicycle industry has grown exponentially over the past decade. Although existing for decades in much smaller numbers, the popularity and credibility of framebuilder entrepreneurship–custom, handmade bike frames–has increased significantly in the past 10 years. The companies that specialize in custom-producing bicycle frames vary in size, scope, reputation, profitability, and even building materials.

To support the standardized evaluation of bicyclist automatic emergency braking (AEB) systems, test scenarios, test procedures and test system hardware and software tools have been investigated and developed by the Transportation Active Safety Institute (TASI) at Indiana University-Purdue University Indianapolis. This paper aims to focus on the development of test scenarios and bicyclist surrogate for evaluating vehicle–bicyclist AEB systems.

The harmonized general estimates system (GES)/FARS 2010-2011 crash data and TASI 110-car naturalistic driving data (NDD) are used to determine the crash geometries and environmental factors of crash scenarios including lighting conditions, vehicle speeds, bicyclist speeds, etc. A surrogate bicyclist including a bicycle rider and a bicycle surrogate is designed to match the visual and radar characteristics of bicyclists in the USA. A bicycle target is designed with both leg pedaling and wheel rotation to produce proper micro-Doppler features and generate realistic motion for camera-based AEB systems.

Based on the analysis of the harmonized GES/FARS crash data, five crash scenarios are recommended for performance testing of bicyclist AEB systems. Combined with TASI 110-car naturalistic driving data, the crash environmental factors including lighting conditions, obscuring objects, vehicle speed and bicyclist speed are determined. The surrogate bicyclist was designed to represent the visual and radar characteristics of the real bicyclists in the USA. The height of the bicycle rider mannequin is 173 cm, representing the weighted height of 50th percentile US male and female adults. The size and shape of the surrogate bicycle were determined as 26-inch wheel and mountain/road bicycle frame, respectively. Both leg pedaling motion and wheel rotation are suggested to produce proper micro-Doppler features and support the camera-based AEB systems.

The results have demonstrated that the developed scenarios, test procedures and bicyclist surrogate will provide effective objective methods and necessary hardware and software tools for the evaluation and validation of bicyclist AEB systems. This is crucial for the development of advanced driver assistance systems.

This paper aims to analyze the effect of a recent disruption of Mexico's gasoline supply chain on the usage of public bike-sharing systems in Mexico City and Guadalajara.

The authors use a detailed data set to understand the usage patterns of Ecobici and Mibici. The authors assess both systems with a differences-in-differences econometric model using the least popular stations as a control group.

The authors find that the number of rides increased significantly shortly after the event because less popular stations became more utilized.

The authors show that when the effects of gasoline shortages were noticeable, usage rates increased in Guadalajara and Mexico City, but the rise primarily came from the users selecting more bikes from the less popular stations. Therefore, the authors show that citizens in both cities regarded bike-sharing as an adequate means of transportation, maximizing system usage during a disruptive time. This finding suggests that cities should invest in improving public bike-sharing systems to reduce carbon emissions and increase their population's well-being.

The authors use a publicly available data set to understand how citizens answered to a major disruption. Furthermore, this is one of the first papers that align supply chain risk management with sustainable transportation and analyzes its effects on citizen behavior in a Latin American setting.

El propósito de este artículo es analizar el efecto de una interrupción en la cadena de suministro de la gasolina en México sobre el uso del sistema de bicicletas públicas en Ciudad de México y Guadalajara.

Usamos una base de datos detallada para entender los patrones de uso de Ecobici y Mibici. Analizamos ambos sistemas a través de un modelo econométrico de diferencias en diferencias utilizando las estaciones menos afectadas como grupo de control.

Encontramos que la utilización del sistema aumentó en número de viajes de manera significativa luego del evento. Esto es debido a que las estaciones menos populares se empezaron a utilizar de manera más intensiva.

Demostramos que los habitantes de las dos ciudades decidieron buscar alternativas de transporte cuando los efectos de la escasez de gasolina se sintieron con fuerza. Esto significa que los ciudadanos consideran que las bicicletas públicas son un medio de transporte adecuado y que durante episodios inoportunos decidieron buscar opciones en las estaciones menos populares maximizando el uso del sistema. Por lo que las ciudades deberían invertir en la mejora de dichos sistemas para que sean más utilizados y así se reduzcan las emisiones de carbono y para que aumente el bienestar en la población.

Utilizamos una base de datos abierta para entender cómo los ciudadanos respondieron a una interrupción importante. Adicionalmente, este es uno de los primeros trabajos que alinea la gestión de riesgos en la cadena de suministros con transporte sostenible y analiza su efecto sobre el comportamiento de los usuarios en un contexto latinoamericano.

The implementation of project-based learning (PBL) activities in the curricula of engineering students has become a consolidated method to improve their skills. The purpose of this paper is to share the experience acquired by the authors from a decennial case-study on a student team PBL activity focused on design and development of human-powered vehicles (HPVs). A review of the project evolution, boundary constraints and management choices could provide inspiration and suggestions to faculty staff that would like to set-up similar experiences for engineering students in their universities.

A student team was funded by the authors in 2008 to gather engineering students interested in design and construction of HPVs. In the past decade, the team has grown from 10 up to 60 students enrolled per year and stimulated to develop a range of HPV designs for sports and mobility. The project management evolved as a consequence to com ply with the growing ambitions of the group and complexity of the goals.

A thorough analysis of factors contributing to the success of the project led to identification of the key factors to increase student participation: persistence of the faculty staff is essential, attending competitions and challenges increases students’ recruitment and formal recognition of the activity through credits and the implementation of intermediate assessment steps increase the active participation rate. Bigger teams reduce the negative impact of recruits eventually abandoning the project in an early stage. Ambitious goals keep students motivated for longer periods and enable a virtuous circle by transferring enthusiasm and knowledge to new members.

The activity is analyzed starting from a subjective experience perspective and some of the findings/conclusions may be not applicable in a different context. However, such review can suggest strategies on the long-term period to create similar conditions elsewhere.

In the last part of the paper, it is pointed out how PBL projects can provide a fertile ground for innovation and lead to patents and development of new products aiming at the market.

This study contributes to provide an insight view of how a student team PBL activity can grow over a decade if guided by faculty staff.

This paper aims to clarify the complex path of negative externalities in the sharing economy and proposes corresponding policy recommendations.

This paper aims to establish an analytical framework for the negative externalities of the sharing economy and to extract the main factors that produce negative externalities, and then, through qualitative comparative analysis method find out how these factors interact to form a negative externality.

Negative externalities in the sharing economy come from the joint effect of the sharing degree of the product or service and constraint mechanism, and the current main modes of the shared economy increase the possibility of negative externalities.

The paper proposes a complex path resulting from negative externalities in the shared economy.

The purpose of this paper is to profile the development of a bicycle parking hub at the University of Tasmania to illustrate how the Academic Operations Sustainability Integration Program promotes real change through the engagement of stakeholders from across an institution to deliver campus sustainability. This case study outlines one example of how place-based learning initiatives focused on campus sustainability challenges have delivered authentic education for sustainability in the Australasian higher education setting.

This case study outlines the process through which a cross-disciplinary place-based learning initiative was designed, implemented and evaluated over a three-year period. The evaluation of the project was designed to assess the impact of this education for sustainability approach on both operational and student learning outcomes, and to make recommendations on the continuation of place-based learning initiatives through the Academic Operations Sustainability Integration Program.

This case study illustrates how learning can be focused around finding solutions to real world problems through the active participation of staff and students as members of a learning community. This experience helped the authors to better understand how place-based learning initiatives can help deliver authentic education for sustainability and the success factors required for engaging staff and students in such efforts.

The case study highlights an example of an education for sustainability initiative that was mutually driven by the operational and learning objectives of an institution, and specifically the ways in which the engagement of staff and students from across an institution can lead to the successful integration of these two often disparate institutional goals.

This paper discusses a case of truck sharing as an application of the sharing economy. This case study examines a real mixed feed company with multiple factories. In this company’s operation, bulk trucks located in a factory had not previously been shared for delivery with other factories to their pre-assigned customers of stock farms. Therefore, this paper suggests a new delivery system that facilitates truck-sharing and analyzes its effects on the transport cost and trucks’ CO₂ emissions. To this end, this paper develops vehicle routing models to represent the current delivery practice and the new truck-shared delivery (TSD). In addition, models are developed for a carbon control policy of an emission trading scheme (ETS) and the effects of the ETS on truck-sharing are investigated. Numerical analysis is conducted to identify the effects of the TSD and the carbon control policy and draw practical implications.