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Evaluating Performance of a Proactive Optimal Variable Speed Limit Control Using Different Objective Functions

Procedia - Social and Behavioral Sciences 2013年 96卷 2895-2906页

作者： Md. Hadiuzzaman Jie Fang Ying Luo Tony Z. Qiu Graduate Research Assistant Department of Civil and Environmental Engineering University of Alberta Edmonton T6G 2W2 Canada Post Doctoral Fellow Department of Civil and Environmental Engineering University of Alberta Edmonton T6G 2W2 Canada Assistant Professor Department of Civil and Environmental Engineering University of Alberta Edmonton T6G 2W2 Canada

Proactive optimal Variable Speed Limit (VSL) control is a promising solution to improve both the freeway capacity and the travel time. Despite this well-recognized fact, most of the previous studies found that the VSL control strategy was capable of improving only the freeway travel time. This finding hinders the overall mobility benefits from the computationally intensive proactive optimal VSL control and its credibility compared to the other control strategies those do not involve real-time traffic state prediction and optimization. To resolve this issue, in this paper, the authors adopt a previously developed novel VSL control strategy that explicitly considers traffic characteristics at active bottleneck, and its upstream-downstream links. Then, the performance of the control strategy has been evaluated within a predictive control framework, considering several objective functions (including stand-alone objective and combination of multiple objectives). Moreover, within the control framework, DynaTAM-VSL has been used as a prediction model. To find the optimal values of control variable at each control horizon, the authors adopt the multi-start Sequential Quadratic programming, which starts a local solver from multiple start points. A sensitivity analysis is performed to see how the weight parameters of the partial objectives influence the VSL performance, which resolves existing paradoxical results of VSL mobility benefits. In addition, the model is simulated for a range of demand inputs, and analysis is carried out to see how efficient the VSL control is to improve the freeway mobility.

关键词： Model predictive control variable speed limit capacity drop METANET DynaTAM-VSL

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Handbook of Sustainability Science in the Future 1

Handbook of Sustainability Science in the Future

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1000年

作者： Walter Leal Filho Anabela Marisa Azul Federica Doni Amanda Lange Salvia

ISBN: (数字)9783031045608

ISBN: (纸本)9783031045592

Humanity will have to cope with many problems in the coming decades: for instance, the world population is likely grow to to 8,8 billion people by 2035. Also, changing climate conditions are negatively affecting the livelihoods of millions of people. In particular, environmental disasters are causing substantial damages to properties. From a social perspective, the inequalities between rich and poor nations are becoming even deeper, and in many countries, conflicts between national and international interest groups are *** above state of affairs suggest that a broader understanding of the trends which may lead to a more sustainable world is needed, especially those which may pave the way for future developments. In other words, we need to pave the way for sustainable futures. Consistent with this reality, the proposed Encyclopedia of Sustainability Futures aims to identify, document and disseminate ideas, experiences and visions from scientists, member of nongovernmental organisations, decision-makers industry representatives and citizens, on themes and issues which will be important in pursuing sustainable future scenarios. In particular, the publication will focus on scientific aspects, as well as on social and economic ones, also considering matters related to financing and infra-structures, which are important in pursuing a sustainable future. The Encyclopedia of Sustainability Futures will involve the contributing authors in line with the principle of co-generation, from across a wide range of disciplines, e.g. education and social sciences, natural sciences, engineering, the arts, languages etc, with papers adopting a long-term sustainability perspective, with a time horizon until 2050. The focus will be on themes which are felt as important in the future, and the chapters are expected to interest and motivate a world audience. This book is part of the "100 papers to accelerate the implementation of the UN Sustainable Development Goals initiative"

关键词： Sustainable Development environmental and Sustainability Education Geography, general

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Assessing the Performance of Machine Learning Algorithms for Water Level Prediction in the Chao Phraya River and its Tributaries: A Focus on Low and High Water Levels

SSRN

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SSRN 2024年

作者： Priyasiri, Wilmat D.S.M. Rittima, Areeya Kraisangka, Jidapa Sawangphol, Wudhichart Phankamolsil, Yutthana Talaluxmana, Yutthana Graduate Program in Environmental and Water Resources Engineering Department of Civil and Environmental Engineering Faculty of Engineering Mahidol University Thailand Faculty of Information and Communication Technology Mahidol University Thailand Environmental Engineering and Disaster Management Program Mahidol University Kanchanaburi Campus Thailand Department of Water Resources Engineering Faculty of Engineering Kasetsart University Thailand

High precision of hydrological prediction is crucial for real–time operation of flood and drought risk mitigation and strategic planning. This study assessed the predictive performances of three Machine Learning (ML) algorithms;XGBoost, Random Forest (RF), and Multi–Layer Neural Networks (MLNNs) for water level prediction with a focus on low and high water levels. The one–day and one–week water level prediction models for six key gauged stations along the Chao Phraya River and its major tributaries were accordingly developed. Selecting the combination of input features was carried out and structured in the prediction model at all gauged stations based on the physical river–reservoir system using past water level, rainfall, controlled reservoir outflow, and upstream discharges with different travel times. The statistical evaluation indicated that both XGBoost and RF, the tree–based ML models, with rainfall input robustly outperformed than MLNNs, as it strongly achieved higher R2 from 0.957 to 0.999 for model training and from 0.743 to 0.995 for model testing and lower MAE, MSE, and RMSE values for all prediction scenarios. Among these three ML algorithms applied for daily prediction, RF demonstrated the superior performance for low water level prediction exhibiting the smallest percentage error of overestimating lying between +0.0088% and +0.9380%. XGBoost, RF, and MLNNs, demonstrated acceptable performance level for high water level prediction as it shows small percentage error of both overestimating and underestimating lying between –2.2696% and +1.1587%. Additionally, it can capture the entire testing dataset with high precision than weekly model. © 2024, The Authors. All rights reserved.

关键词： Rain

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Blank slate engineering at Florida Gulf Coast University - Innovative and multidisciplinary from the ground up

Blank slate engineering at Florida Gulf Coast University - I...

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113th Annual ASEE Conference and Exposition, 2006

作者： Blanchard, Susan Egiebor, Nosa Sweeney, James Zidek, Lisa Sechrist, Chalmers Hulbert, Sam Osborn, James O'Neill, Robert Florida Gulf Coast University United States FGCU School of Engineering Institute of Electrical and Electronics Engineers Biomedical Engineering Society American Institute for Medical and Biological Engineering United Kingdom Department of Environmental and Civil Engineering Arizona State University United States Department of Bioengineering Department of Bioengineering Arizona State University United States Flinn Foundation Funded Multi- and Interdisciplinary Graduate Training Program in Bioengineering Milwaukee School of Engineering United States Graduate Programs Industrial Engineering Program Department of Electrical and Computer Engineering Department of Engineering University of Illinois Urbana-Champaign United States Institute of Electrical and Electronics Engineers Rose-Hulman Institute for Technology School of Engineering FGCU School of Engineering's Advisory Board Roger Williams University United States Department of Civil Engineering Department of Engineering Roger Williams University United States

No abstract available

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Simulation of multilayer shallow water fluid flow using lattice boltzmann modeling and high performance computing

Simulation of multilayer shallow water fluid flow using latt...

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World environmental and Water Resources Congress 2009: Great Rivers

作者： Tubbs, K.R. Tsai, F.T.-C. Donald W. Clayton Graduate Program in Engineering Science Louisiana State University 351 Johnston Hall Baton Rouge LA 70803 United States Department of Civil and Environmental Engineering Louisiana State University 3418G Patrick F. Taylor Hall Baton Rouge LA 70803-6405 United States

ISBN: (纸本)9780784410363

A lattice Boltzmann method (LBM) on high performance computing (HPC) environments for three-dimensional shallow water flow fields is developed. Recently, the LBM has become an attractive numerical method to solve various fluid dynamics phenomena. However, LBM has not been extensively applied to shallow water equations. The shallow water equations have wide applications in ocean and hydraulic engineering which can benefit from the advantages of the LBM. The standard LBM for two dimensional shallow water flows is extended to three dimensional flows by solving the multilayer shallow water equations. LBM is an attractive method for solving the multilayered shallow water equations because the extension to a multilayer formulation is straight forward and all simplicities and advantages of the LBM are retained. The performance of the LBM for the multilayer shallow water equations is investigated and optimized in HPC environments. We numerically demonstrate the applicability of the LBM in three dimensional shallow water flows and the LBM performance using OpenMP. © 2009 ASCE.

关键词： Multilayers

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A weekend STEM enrichment program for tribal high school teachers and students

A weekend STEM enrichment program for tribal high school tea...

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113th Annual ASEE Conference and Exposition, 2006

作者： Padmanabhan, G. Lin, Wei Pieri, Robert Patterson, Floyd Khan, Eakalak North Dakota State University United States Department of Civil Engineering North Dakota State University United States North Dakota Water Resources Research Institute United States ASEE American Society of Civil Engineers United States Department of Environmental Engineering North Dakota State University United States Interdisciplinary Environmental and Conservation Sciences Graduate Program United States NDSU United States Department of Mechanical Engineering North Dakota State University United States Department of Electrical Engineering North Dakota State University United States

Attracting high school students to college engineering programs has been recognized as a challenge by several engineering organizations. One of the reasons for the low percentage enrolment of high school graduates into engineering programs is that many math/science teachers and counselors lack understanding of engineering applications within the subjects they teach and prospects associated with engineering careers. The instruction at the school level is often criticized for not adequately emphasizing science and mathematics, especially connections with engineering applications. Many students have difficulty connecting math and science courses to common phenomena seen all around and to future careers. This problem is further aggravated on Indian reservations in North Dakota because of their isolated locations and distance from industries. The authors developed a weekend academic program, "Sunday Academy", carried out on four North Dakota Indian reservations, to stimulate Native American students' interest in science, technology, engineering, and mathematics (STEM), to attract to engineering programs, and to engage high school teachers and tribal college instructors in the process of developing engineering and applied science lesson plans. The academy consisted of a series of one-day academic sessions presented monthly to junior and senior high school students. The lesson plans for the sessions were developed collaboratively by a group of university and community college faculty and high school teachers. This project provided unique opportunities for engineering professors to work with high school students directly, to familiarize high school teachers and tribal college instructors with engineering concepts and approaches, and to be knowledgeable about and sensitive to Indian culture. To make it a successful program, the authors had to overcome various challenges, including selection of lesson topics and hands-on activities that are interesting and suitable for the st

关键词： engineering education

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Assessing the performance of eggshell ash as a sustainable bitumen modifier

Transportation Engineering

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Transportation engineering 2023年 13卷

作者： Syammaun, Tamalkhani Husaini Abdullah Isya, Muhammad Rachman, Firmansyah Doctoral Program School of Engineering Post Graduate Program Universitas Syiah Kuala Banda Aceh23111 Indonesia Department of Civil Engineering Universitas Muhammadiyah Aceh Banda Aceh23123 Indonesia Department of Mechanical Engineering Universitas Syiah Kuala Banda Aceh23111 Indonesia Department of Civil Engineering Universitas Syiah Kuala Banda Aceh23111 Indonesia

The disposal of eggshells in landfills presents an ongoing global environmental issue that demands immediate attention. However, a promising solution lies in utilizing eggshells as modifiers in bitumen binders, offering a sustainable approach to alleviating this burden. This study focuses on crushing eggshells to produce eggshell ash, which is then explored as a potential modifier in bitumen binders. The objective is to evaluate the properties of modified bitumen binders incorporating eggshell waste sourced from the food industry and examine their application in bitumen engineering. The optimal weight percentage of eggshell ash in the bitumen is determined, considering four levels (5, 7, 10 and 12%) and two heating temperatures (100 and 200 °C). Several tests are conducted to comprehensively evaluate the eggshell ash, including SEM-EDS and FTIR analyses, providing valuable technical insights into its properties. Additionally, DSR measurements are employed to analyze the characteristics of the bitumen incorporating eggshell ash. The primary oxide group present in the eggshell ash is CaCO3. Notably, higher concentrations of eggshell ash enhance the resistance of bitumen binders to high temperatures, as indicated by the penetration index results. Furthermore, DSR testing reveals that adding eggshell ash increases the rigidity of the bitumen binders, resulting in improved resistance to deformation. © 2023 The Author(s)

关键词： Binders

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Kinetic Behaviors and Nitrite Accumulation of Thiosulfate Autotrophic Denitrification Process

SSRN

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SSRN 2024年

作者： Chang, Jenting Septiariva, Iva Yenis Yang, Youren Chuang, Shun-Hsing Graduate Institute of Environmental Engineering National Central University Taoyuan City32001 Taiwan Civil Engineering Study Program Sebelas Maret University Surakarta57126 Indonesia

Exploration of the effects of different S/N ratios on the accumulation of NO2-N in the autotrophic denitrification process is crucial due to no need for an external organic carbon supply. Herein, thiosulfate-driven autotrophic denitrification (SADN) was established in a sequencing batch reactor treating nitrate-containing wastewater. The long-term and batch tests observed that when sufficient thiosulfate was present, the branched thiosulfate oxidation (BTO) reaction occured. Therefore, the sulfur-to-nitrogen (S/N) molar ratio had to be maintained over 2.19 to provide enough electron donors for complete denitrification with SNaRR of 13.13 mg NO3-N/g ***. If the S/N molar ratio declined to 1.75, some nitrite accumulation would utilize the stored elemental sulfur. SNiRR increased from 0.4 – 20.1 mg NO2-N/g *** when the S/N ratio rose from 1.46 to 4.38. Under a sufficient S/N ratio, the change in nitrogen concentration followed a zero order reaction. The microbial analysis identified Desulfobacterota as key microbes, with autotrophic denitrifying bacteria accounting for more than 70%. © 2024, The Authors. All rights reserved.

关键词： Denitrification

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Budget-constrained rail network electrification problem

arXiv

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arXiv 2021年

作者： Patil, Priyadarshan N. Walthall, Rydell Boyles, Stephen D. Graduate Program in Operations Research and Industrial Engineering The University of Texas Austin United States Department of Civil Architectural and Environmental Engineering The University of Texas Austin United States

We consider a budget constrained rail network electrification problem with associated changes in costs of energy usage (via path gradient and curvature), operations, and long-term maintenance. In particular, we consider that freight flows on such a network form a user equilibrium. Interactions between electric and diesel trains on the same corridor are represented with nonseparable link performance functions, which nevertheless have a symmetric Jacobian. This bi-level formulation is solved for the North American railroad network using a genetic algorithm (GA), incorporating domain-specific insights to reduce the number of solutions which must be considered. We analyze solution characteristics and decision-making implications. Results show that broad connectivity would be beneficial for most impact. Increasing demand shifts electrified corridors towards the more populous east and gulf coasts, while increased operational costs results in electrification of routes through mountainous terrains. © 2021, CC BY.

关键词： Electric utilities

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Acid-catalyzed hydrothermal treatment of sewage sludge: effects of reaction temperature and acid concentration on the production of hydrolysis by-products

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Biomass Conversion and Biorefinery 2023年第9期13卷 7533-7546页

作者： Pham, Van Toi Guan, Chung-Yu Han, Po-Chun Matsagar, Babasaheb M. Wu, Kevin C. W. Ahamad, Tansir Chang, Ching-Yuan Yu, Chang-Ping Graduate Institute of Environmental Engineering National Taiwan University Taipei106 Taiwan Faculty of Environmental Engineering National University of Civil Engineering 55 Giai Phong Hai Ba Trung Hanoi100000 Viet Nam Department of Environmental Engineering National Ilan University Yilan260 Taiwan Ph.D. Program of Green Materials and Precision Devices National Taiwan University Taipei10617 Taiwan Department of Chemical Engineering National Taiwan University No. 1 Sec. 4 Roosevelt Road Taipei10617 Taiwan Department of Chemistry College of Science King Saud University P.O. Box 2455 Riyadh11451 Saudi Arabia Water Innovation Low Carbon and Environmental Sustainability Research Center National Taiwan University Taipei106 Taiwan

Sewage sludge (SS) is an organic biomass from wastewater treatment plants, but the use of SS to produce bio-based chemicals under acid-catalyzed hydrolysis (ACH) processes is not well investigated. In this study, ACH processes were performed at 120, 150, and 180 °C using sulfuric acid (H2SO4) with concentrations of 0–0.5 M within a reaction time of 90–180 min to produce bio-based chemicals from SS. The results showed that the reaction temperature, reaction time, and concentrations of H2SO4 affected the yields of sugars, levulinic acid (LA), and 5-hydroxymethylfurfural (HMF). The highest xylose and glucose yields were 7.69 mol% and 5.22 mol% at 120 °C with 0.5 M H2SO4 during the 180 min of reaction time, respectively. Besides, under the ACH process at 180 °C and 180 min, the yield of LA reached a maximum value of 0.48 mol% at 0.5 M H2SO4, and the highest yield of HMF was 1.66 mol% at 0.1 M H2SO4. The data obtained also indicated that the ACH process led to an increase in soluble chemical oxygen demand, dissolved organic carbon, and total dissolved nitrogen. Fluorescence excitation-emission matrix of dissolved organic matter and thermogravimetric analysis of the treated SS further supported the enhanced solubilization of SS after ACH process, especially under higher reaction temperature and concentrations of H2SO4. Although the lower yields of bio-based chemicals might restrict the downstream recovery of the target products, the largely improved SS solubilization by ACH suggests that acid-catalyzed hydrothermal hydrolysis process has potential as an alternative pretreatment method of SS. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.

关键词： Sewage sludge

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