1,721,253 research outputs found
Reducing Greenhouse Gas Emissions of the Transport Sector in Urban Areas: Assessing Possible Actions Through Specific Performance Indicators
No full textThe transport sector is responsible for more than a quarter of the total Greenhouse Gas (GHG) emissions. Several actions can be implemented to reduce them, especially in the urban areas. For this reason, to facilitate the selection of the actions to be implemented, a literature review was carried out to provide a list of actions that the different stakeholders can adopt. Moreover, to facilitate their assessment, a set of Performance Indicators (PIs) was formalized, exploring their impacts on four sectors, including environmental, energy, social, and economic. Finally, considering the pivotal role of local public transport in reducing GHG emissions in urban areas, an example of the actions implemented by Gruppo Trasporti Torinese, which is the local public transport company of Turin is presented
Compaction performance analysis of alum sludge waste modified soil
No full textSustainable construction is one of the ultimate requirements of the engineering field. Addition of waste materials not only contribute to the improvement of the density of soils but also help in the enhancement of its strength properties. In the field, compaction is achieved by compactors and rollers, which consumes a lot of energy for this purpose. In this study, two methods related to compaction energy have been applied to study the relation of compaction energy with the strength of soil before and after addition of alum sludge as a soil stabilizer. An advanced Artificial Neural Networks (ANN5) technique has been applied with reference to the addition of alum sludge percentage, plasticity index, specific gravity, optimum moisture content, maximum dry density, AASHTO classification, USCS classification, and group index. It was found that soil strength can be improved even at a low compaction energy level of 600KN-m/m(3) by the addition of optimum percentage of 8% alum sludge as a soil stabilizer. So, roller compaction effort can also be reduced by addition of this soil stabilizer to save compaction cost i.e. saving of roller fuel consumption and rental cost as well. This study will not only help in environment-friendly construction but will also manage finance by utilization of optimum compaction energy in the mega projects.Shah, SAR (reprint author), Pakistan Inst Engn & Technol, Dept Civil Engn, Khanewal Rd, Multan 60000, Pakistan.
[email protected]
Figure 2 in An assessment of food habits and altitudinal distribution of the Asiatic black bear (Ursus thibetanus) in the Western Himalayas, Pakistan
No full textFigure 2. (1) Maize crop raided by a black bear in Malkandi reserve forest area, Kaghan Valley, Pakistan, 2013–2014. (2, 3) Photographs of scats found near the same forest area where bears raided maize crops.Published as part of Ali, Ashfaq, Zhou, Zhixiang, Waseem, Muhammad, Khan, Muhammad Fiaz, Ali, Ishtiaq, Asad, Muhammad & Qashqaei, Ali Turk, 2017, An assessment of food habits and altitudinal distribution of the Asiatic black bear (Ursus thibetanus) in the Western Himalayas, Pakistan, pp. 689-701 in Journal of Natural History 51 (11-12) on page 697, DOI: 10.1080/00222933.2017.1303097, http://zenodo.org/record/518025
Flexibility assessment indicator for aggregate residential demand
No full textIn the modern power system, characterization of customer's demand plays a vital role for Demand Side Management. Demand flexibility information, extracted from the aggregate demand behaviour of customers, presents more comprehensive picture for the aggregator or system operator. There is an existence of diverse flexible time slots during a day in different time periods. Due to the diverse energy consumption behaviour of the residential customers, extraction of flexibility and its associated potential time durations is a challenging task. To extract flexibility information from aggregate residential customers, a flexibility indicator is formulated in this paper. Information presented gives an indication about flexible time slots in terms of numerical value that is useful for a system operator or an aggregator for demand side flexibility assessment and this will lead to design and initiate DSM programs
An assessment of food habits and altitudinal distribution of the Asiatic black bear (<i>Ursus thibetanus</i>) in the Western Himalayas, Pakistan
No full textAli, Ashfaq, Zhou, Zhixiang, Waseem, Muhammad, Khan, Muhammad Fiaz, Ali, Ishtiaq, Asad, Muhammad, Qashqaei, Ali Turk (2017): An assessment of food habits and altitudinal distribution of the Asiatic black bear (Ursus thibetanus) in the Western Himalayas, Pakistan. Journal of Natural History 51 (11-12): 689-701, DOI: 10.1080/00222933.2017.1303097, URL: http://dx.doi.org/10.1080/00222933.2017.130309
Digital Twin Implementation for Urban Tram Systems: A Data-Driven Model for Estimating Traction Current
No full textThe urgent need to decarbonize our cities places the transport sector, responsible for a significant share of greenhouse gas emissions, at the center of global sustainability efforts. Achieving this goal requires not only the electrification of public transport systems but also ensuring their efficiency and effectiveness to encourage widespread adoption over private vehicles. A promising strategy to modernize such systems is the implementation of a Digital Twin (DT), a virtual counterpart of the infrastructure that integrates real-time field data from strategically deployed sensors. This work focuses on trambased urban transport systems, where one of the most critical parameters for DT applications is the traction current absorbed by each vehicle. However, the deployment of dedicated onboard current sensors is often constrained by economic and timerelated limitations. To address this, we propose a transitional solution: a data-driven model capable of estimating tram current consumption using only GPS-based vehicle position data. Specifically, this paper presents a hybrid neural network architecture combining Long Short-Term Memory (LSTM) and Gated Recurrent Unit (GRU) models. The network processes speed and acceleration profiles derived from open-access GPS data, eliminating the need for onboard instrumentation. The model was trained and validated with data from a targeted field measurement campaign, achieving a Mean Absolute Error (MAE) of 61.3 A and a Root Mean Square Error (RMSE) of 95.6 A. Given that the maximum absorbed current exceeds 900 A, these error values indicate that the model's predictive performance is within an acceptable range. This methodology provides a robust, low-cost solution for enabling early-stage DT development in Urban Traction Electrification Systems (UTES), supporting simulation and planning in the ongoing digital transformation of public transport
Optimal Operation of a Smart Electrified Traction System: A Review
No full textSmart Electrified Traction Systems (SETS) ma: play a pivotal role towards the decarbonization of the transpor sector and the integration of renewable energy sources. For thi reason, the paper proposes an up-to-date state of the art revier of the main configurations, operational schemes and flexibl assets forming these networks. Also, the intrinsic flexibility 0 these tractions systems calls for the optimal management of th assets in order to minimize the operational costs. This pape also reviews the main formulations of customized optimal powe flow problems, which incorporate the intrinsic features of thes networks. The critical analysis focuses on the reformulation techniques or algorithms adopted to overcome non-linear an non-convex constraints, typical of optimal power flow problems
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
- …
