Transport costs, distance, and time : evidence from the Japanese Census of Logistics

Geographic distance is a standard proxy for transport costs under the simple assumption that freight fees increase monotonically over space. Using the Japanese Census of Logistics, this paper examines the extent to which transport distance and time affect freight costs across shipping modes, commodity groups, and prefecture pairs. The results show substantial heterogeneity in transport costs and time across shipping modes. Consistent with an iceberg formulation of transport costs, distance has a significantly positive effect on freight costs by air transportation. However, I find the puzzling results that business enterprises are likely to pay more for short-distance shipments by truck, ship, and railroad transportation. As a plausible explanation, I discuss aggregation bias arising from freight-specific premiums for timely, frequent, and small-batch shipments.

Alexandri de Alexandro Dies geniales ...

Pie de imp. tomado del colofón en 2[rum]6v

Characterization of a Right Angle Transfer Point in a Fruit Packing Line

Characteristics of the impacts su!ered by the fruit on a transfer point of an experimental fruit packing line were analysed. The transfer is made up by two transporting belts at di!erent heights forming an angle of 903. These transfer points are very common in fruit packing lines, in which fruits receive two impacts: the "rst onto the belt base and the second into the lateral plate. Diferent tests were carried out to study the e!ect of transfer height, velocity, belt structure and padding on the acceleration values recorded by an instrumental sphere (IS 100). Results showed that transfer height and belt structure a!ect mainly impact values on the belt base, and padding a!ects mainly impact values registered for lateral contact. The elect of belt velocity in both impacts is less important when compared to the rest of the variables. Additionally, two powered transfer decelerators were tested at the same point with the aim of decreasing impacts su!ered by the fruit. Comparing impacts registered using these decelerators to those analysed in the first part of the study without decelerators, a high reduction of the impact values was observed.

Una prospectiva de las tecnologías de las estructuras espaciales. Los puentes

El objetivo de este artículo es intentar predecir las tendencias en esta clase tan importante de estructuras espaciales. Trata en primer lugar acerca de los mecanismos para el desarrollo de los puentes. A continuación se describe la evolución de los diferentes componentes de la tecnología de los puentes y su repercusión sobre los proyectos. Posteriormente se muestran algunos ejemplos representativos de proyectos actuales de puentes.