Naoto Itani (p), Kazunari Tanaka

Alessia Tagliabue

1. Introduction
In recent years, Japan faces the problem of declining birthrate and aging population. This problem is very serious in the construction industry. About a quarter of the total workforce is over 60 years old. The number of engineers needed to maintain the infrastructure of Japan is insufficient.
Additionally, the number of aging infrastructures in Japan is expected to increase rapidly. In particular, the aging of bridges presents a major challenge in Japan. A significant portion of social infrastructure was intensively constructed during the period of rapid economic growth. The percentage of bridges over 50 years old is projected to rise from approximately 37% in March 2023 to 54% in March 2030 and 75% in March 2040. Therefore, it is important to prioritize bridge maintenance. The goal of this study is to develop a method for assessing bridge deterioration more efficiently.

2. Purpose and method
The purpose of this study is to estimate bridge deterioration by some natural environment. In this study, we analyzed using the Random Forest algorithm. In this analysis, we researched bridges in Fukushima Prefecture. The dataset included 13,563 bridges and was formatted as a CSV file. For creating the dataset, we integrated the information of natural environment and bridges using GIS. From the results of the analysis, we computed the SHAP values for analyzing the most influential factors affecting bridge deterioration.

3. Result of analysis
This study revealed some natural environments have the positive and negative impact for estimating bridge deterioration. Natural environment, particularly, distance from the coastline and wind speed, are importance to estimate bridge deterioration. Additionally, structural attributes such as bridge lengths and year of construction are important.

4. In conclusion
In this study, we attempted to estimate bridge deterioration by using the Random Forest algorithm. This study clarifies the importance of variables such as distance from the coastline, precipitation, and wind speed for estimating the degree of deterioration. This study has the potential to predict the environmental impacts in the early design stages of infrastructure projects.
Future research will focus on improving the accuracy of this model by using population data, aerial photography and other environmental factors.

Alessia Tagliabue (p), Matteo Scacchi, Ila Maltese, Elena Maggi

Vania Licio

The textile industry is among the largest contributors to global environmental degradation due to its reliance on linear production models and resource-intensive processes. Reverse Logistics, or Circular Logistics (CL), has the potential to support Circular Economy (CE) initiatives. However, its heavy reliance on road transport can significantly undermine the expected environmental benefits. This study, developed within the NODES (Nord Ovest Digitale e Sostenibile) project funded by Next Generation EU, explores how textile companies can redesign logistics processes to optimize CL operations. The research aims to identify key success factors for CL implementation in the textile sector while assessing the economic and environmental benefits of integrating CL and CE strategies.
Adopting a case study approach, this research builds on a systematic review of international best practices in CE and CL. The literature review encompasses not only the identification of successful models from the textile industry and other sectors, but also an examination of the main barriers to efficiently implement CL processes, including logistics complexity, high costs and regulatory challenges. The empirical study focuses on a sample of textile companies in Northern Italy, and collects data through interviews, direct observations and company reports to assess how CE principles are applied in CL operations. The findings are then used to test and validate innovative and sustainable solutions for optimising the logistics process managing circular economy flows.
This study is distinguished by its integration of theoretical insights and real-world application, thereby providing practical suggestions for textile companies transitioning towards circular business models, able to enhance their reverse logistics efficiency and reduce their environmental impact. By outlining strategies to improve both economic viability and environmental sustainability, it contributes to the ongoing debate on circular supply chain management. Moreover, the analysis of participating companies offers concrete recommendations for fostering industrial symbiosis and resource-sharing networks.

Vania Licio (p)

Pedro Amaral

This paper analyzes the effect played by the transport infrastructure in the development of the Democratic Republic of the Congo (DRC). Historically, water was the main mean of transport for the movement of goods and people. However, thanks to advances in technology, during the last two hundred years, railways, first, and highways, then, became the main means of transport in modern economies. In the developing and underdeveloped world, rivers hold their key historical role. States that benefit from the existence of navigable inland waterways (like rivers or canals) take advantage of their transport function. In these countries, the often poor, ruined, and fragmented rail and road networks represent the main obstacles that prevent the positive effect that transport infrastructure could have on economic growth, and the dependence on natural means of transport is higher compared to the developed world. The Congo River, which constitutes an intricate transport system of waterways of more than 15,000 km, represents the backbone of the transport infrastructure in the DRC, where the trimodal river-railway-road network is headed by the river. Rivers, if navigable, have a twofold `nature': they are a pure geographical condition (first-nature geography) and act as a transport infrastructure (second-nature geography). This `dual role' is still neglected and has not explicitly been considered in the literature. On the other hand, together with the man-made infrastructure, navigable rivers constitute an integrated system of complementary `goods': areas, where rivers are navigable, do not have railways or main roads. By using 10x10 km grid cells and geocoded data, this paper investigates, on the one hand, how beneficial is the Congo River for the economic development (mining activity, crop production, nightlight luminosity) of the DRC; on the other, it focuses on the relationship between natural and man-made transport infrastructure. Empirical results show that if both railways and roads, although in a dilapidated condition, positively affect contemporary economic development, the Congo River and the whole network of tributaries and small rivers fall short of the role they could have in the economic growth of the country. The inter-modal river-rail-road transport system is still far from being a real opportunity for the country: the waterway transport benefits from the existence of the man-made one, but the reverse does not apply.

Victor Medeiros, Rafael Ribeiro, Pedro Amaral (p)

Naoto Itani

This study evaluates the regional impacts of highway infrastructure development on greenhouse gas (GHG) emissions. To this end, we use detailed local-level data from Brazilian municipalities during the Growth Acceleration Program (PAC) period (2007-2018) and apply an instrumental variable identification approach to circumvent endogeneity concerns related to the non-random placement of roads. We find that a 1% increase in road investments raises CO2 emissions by 0.025%. Those damaging highway effects are sustained for the road, energy, and land use change sectors. In addition, findings point out heterogeneous road impacts on CO2 emissions depending on agglomeration, population scale, deforestation, and technology. From the econometric estimates, we calculate an average CO2 emissions return rate to highway investments (ERR) of 3.0%, implying a discount on the economic benefits of road investments proved in past studies. Finally, we measure a sustainable return rate to highway investments (SRR) of around 17%, indicating a widespread need to develop the Brazilian transportation sector. From a regional perspective, it is important to note the deep heterogeneities in Brazil, wherein the results shed light on negative SRRs for some regions and the large regional variability. This research offers valuable insights for policymakers, technicians, financial institutions, and civil society in shaping effective and environmentally conscious road policies.