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Nutrient distribution within and release from the contaminated sediment of Haihe River

Journal of Environmental Sciences 2011年第7期23卷 1086-1094页

作者： Min Wu Suiliang Huang Wei Wen Xueming Sun Xianqiang Tang Miklas Scholz Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of Education Nankai University Tianjin 300457 China Numerical Simulation Group for Water Environment Tianjin Key Laboratory of Environmental Remediation and Pollution Control College of Environmental Science and Engineering Nankai University Tianjin 300071 China Civil Engineering Research Centre School of Computing Science and Engineering The University of Salford Newton Building Salford M5 4WT England United Kingdom

We assessed nutrient characteristics, distributions and fractions within the disturbed and undisturbed sediments at four sampling sites within the mainstream of Haihe River. The river sediments contained mostly sand （ 60%）. The fraction of clay was 3%. Total nitrogen （TN） and total phosphorus （TP） concentrations ranged from 729 to 1922 mg/kg and from 692 to 1388 mg/kg, respectively. Nutrient concentrations within the sediments usually decreased with increasing depth. The TN and TP concentrations within the fine sand were higher than for that within silt. Sediment phosphorus fractions were between 2.99% and 3.37% Ex-P （exchangeable phosphorus）, 7.89% and 13.71% Fe/Al-P （Fe, Al oxides bound phosphorus）, 61.32% and 70.14% Ca-P （calcium-bound phosphorus）, and 17.03% and 22.04% Org-P （organic phosphorus）. Nitrogen and phosphorus release from sediment could lead to the presence of 21.02 mg N/L and 3.10 mg P/L within the water column. A river restoration project should address the sediment nutrient stock.

关键词： total nitrogen and phosphorus calcium-bound phosphorus organic phosphorus undisturbed aquatic sediment disturbed aquatic sediment river restoration

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Modeling and evaluation of cyber-physical systems in civil engineering

Modeling and evaluation of cyber-physical systems in civil e...

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88th Annual Meeting on the International Association of Applied Mathematics and Mechanics, GAMM 2017

作者： Legatiuk, Dmitrii Dragos, Kosmas Smarsly, Kay Applied Mathematics Bauhaus University Weimar Germany DFG Research Training Group 1462 Bauhaus University Weimar Germany Computing in Civil Engineering Bauhaus University Weimar Germany

A cyber-physical system (CPS) is a coupled system integrating computing, networking, and physical processes. Through actuation, cyber-physical systems control the physical processes, usually with feedback loops, where the physical processes affect computing and networking processes, and vice versa. In civil engineering, the most common fields of CPS applications are structural health monitoring (SHM) and structural control. A typical CPS task is the assessment of a structure based on (i) collected measurement data and (ii) a corresponding model. However, for an accurate and precise assessment of a structure, the CPS itself must be modeled and evaluated. In this paper, a conceptual modeling and evaluation approach is proposed, in which each part of a CPS is evaluated individually. In this study, the conceptual approach is presented for modeling and evaluation of CPS in civil engineering. The evaluation is based on an abstract approach allowing a discussion of a principle (i.e. general) model structure of a CPS, identifying critical issues to be studied in more detail in future research. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

关键词： Cyber Physical System

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Iodide-mediated electroreduction of carbon dioxide for efficient and selective electrosynthesis of multicarbon products over copper iodide microcrystals

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Journal of Colloid and Interface Science 2025年 696卷 137847页

作者： Fitri Nur Indah Sari Tzu-Hsuan Wang Ming-Chieh Hsieh Tzu-Hao Kuan Miller Alonso Camargo-Valero Chia-Yu Lin Department of Chemical Engineering National Cheng Kung University (NCKU) Tainan City 70101 Taiwan BioResource Systems Research Group School of Civil Engineering University of Leeds Leeds LS2 9JT United Kingdom Hierarchical Green-Energy Materials (Hi-GEM) Research Center National Cheng Kung University (NCKU) Tainan 70101 Taiwan Program on Key Materials & Program on Smart and Sustainable Manufacturing Academy of Innovative Semiconductor and Sustainable Manufacturing National Cheng Kung University (NCKU) Tainan 70101 Taiwan

Electrochemical CO 2 reduction ( e -CO 2 RR) to multicarbon (C 2+ ) products serves as a sustainable route for renewable energy storage, chemical synthesis, and mitigating CO 2 emission. In this study, we report on the CuI microcrystals modified gas-diffusion electrode ( micro CuI), prepared with the successive ion layer adsorption and reaction method, with high-performance towards the generation of C 2+ products from e -CO 2 RR. The micro CuI electrode exhibited remarkably high current efficiency towards the generation of C 2+ products ( i.e. , ethylene, ethanol, and 1-propanol), but suffered instability due to the formation of inactive copper (II) carbonate hydroxide within 2-h electrolysis. As compared to other halide ions, the inclusion of a suitable amount of I − ions during the electrolysis minimized the corrosion and effectively regulated the oxidation state of surface copper species (OS Cu ) and transformed micro CuI into aggregates of Cu 0 /Cu 2 O nanoparticles, with Cu 0 embedded in a Cu 2 O matrix. The suitable OS Cu (∼0.7) combined with synergistic catalytic effects from Cu 0 and Cu 2 O enabled high stability and realized high current efficiency (73.6 ± 2.2 %) and high energy efficiency (48.8 ± 1.8 %) for the generation of C 2+ products in the prolonged electrolysis at −100 mA cm −2 . Finally, the I − ion-mediated e -CO 2 RR scheme was also demonstrated to effectively boost the current efficiency and energy efficiency of the micro CuI electrode towards the generation of C 2+ products from the electrocatalytic reduction of low-concentration CO 2 in the simulated biogas atmosphere.

关键词： Cu oxidation state Electrochemical upcycling of CO(2) Multicarbon product SILAR deposition Synergistic catalysis

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The Coupled Effect of Temperature Changes and Damage Depth on Natural Frequencies in Beam-Like Structures

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Structural Durability & Health Monitoring 2022年第1期16卷 15-35页

作者： Tareq Al-hababi Nizar Faisal Alkayem Li Cui Shixiang Zhang Cong Liu Maosen Cao Anhui Provincial International Joint Research Center of Data Diagnosis and Smart Maintenance on Bridge Structures Chuzhou UniversityChuzhou239000China Department of Engineering Mechanics Hohai UniversityNanjing210098China College of Civil and Transportation Engineering Hohai University Nanjing210098China College of Civil and Architecture Engineering Chuzhou UniversityChuzhou239000China China Design Group Co. Ltd.Nanjing210014China Jiangsu Zhongqiao Technology Research Co. Ltd.Nantong226000China

A significant amount of research is concerned with dynamic modal parameters for damage detection of structural conditions due to their simplicity in use and ***,their use for damage detection should be performed with special attention,particularly in operational and environmental conditions subjected to temperature *** in construction industries experience different loading types,such as temperature changes leading to crack initiation and *** physical and dynamic properties such as natural frequencies and mode shapes indicate that damage has occurred within the *** this study,vibration analysis of cantilever and cantilever simply supported beams has been carried out on intact and damaged beams to investigate the coupled effect of temperature changes and damage depth on natural frequencies.A numerical analysis of beams is completed using ANSYS *** results of numerical simulation are validated using two other studies from *** results revealed that in order to perform a successful damage assessment using the frequency shift,the vibration modes should be selected *** addition,an increase in temperature results in a decrease in structural *** assessment of the effect of damage depth on natural frequencies also confirms that when damage depth is increased,there is a significant decrease in natural frequency responses.

关键词： Temperature effect damage depth natural frequency beam damage detection modal analysis

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The behavior of functionally graded concrete and the prospect of material optimization

The behavior of functionally graded concrete and the prospec...

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Central Europe Towards Sustainable Building 2016: Innovations for Sustainable Future, CESB 2016

作者： Han, Aylie Gan, Buntara Sthenly Kristiawan, S.A. Trtnh, Thanh Huong Structural and Material Laboratory Diponegoro University Semarang Indonesia Department of Architecture College of Engineering Nihon University Koriyama Japan SMART Crete Research Group Civil Engineering Department Sebelas Maret University Surakarta Indonesia Graduate School of Engineering Nihon University Koriyama Japan

ISBN: (纸本)9788027102488

Functionally Graded Concrete (FGC) finds its origin in the metal and ceramic industry where materials are produced with a gradation in mechanical properties throughout the depth of abeam section. A study on the methodology for producing FGC was conducted, and the resulting material analyzed, to evaluate the behavior of the graded concrete. The study was performed both numerically and experimentally. It was found that the compressive strength of an FGC is predominately influenced by the strength of the lower grade concrete, while the stiffness of the material closely approaches that of the higher strength concrete. Additionally, it was shown that the resulting FGC does not follow the stress-strain response as stated in the fib-CEB code. An FGC element has the potentials of cement-use reduction, by optimizing the required strengths in accordance to the behavior of a section in bending. Since the tensile capacity in reinforced concrete elements in bending is not accounted for, an FGC element could considerably reduce the cement content in these areas, contributing positively to the conservation of natural resources and reducing carbon emission during cement production.

关键词： Cements

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A security scheme for intelligent substation communications considering real-time performance

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 948-961页

作者： Jie ZHANG Jun’e LI Xiong CHEN Ming NI Ting WANG Jianbo LUO Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of EducationSchool of Cyber Science and EngineeringWuhan UniversityWuhan 430072China NARI Group Corporation(State Grid Electric Power Research Institute) Nanjing 211106China NARI Technology Co.Ltd. Nanjing 211106China State Key Laboratory of Smart Grid Protection and Control Nanjing 211106China

Tampering,forgery and theft of the measurement and control messages in a smart grid could cause one breakdown in the power ***,no security measures are employed for communications in intelligent *** services in an intelligent substation have high demands for real-time performance,which must be considered when deploying security *** paper studies the security requirements of communication services in intelligent substations,analyzes the security capabilities and shortages of IEC 62351,and proposes a novel security scheme for intelligent substation *** security scheme covers internal and telecontrol communications,in which the real-time performance of each security measure is *** this scheme,certificateless public key cryptography(CLPKC)is used to avoid the latency of certificate exchange in certificate-based cryptosystem and the problem of key escrow in identity-based cryptosystem;the security measures of generic object-oriented substation event,sampled measure value and manufacturing message specification in IEC 62351 are improved to meet the real-time requirements of the messages as well as to provide new security features to resist repudiation and replay attacks;and the security at transport layer is modified to fit CLPKC,which implements mutual authentication by exchanging ***,a deployment of CLPKC in an intelligent substation is *** also evaluate the security properties of the scheme and analyze the end-to-end delays of secured services by combining theoretical calculation and simulation in this *** results indicate that the proposed scheme meets the requirements of security and real-time performance of communications in intelligent substations.

关键词： Intelligent substation Security measures Certificateless public key cryptography(CLPKC) Real-time communication IEC 62351

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Evaluation of traditional and machine learning approaches for modeling volatile fatty acid concentrations in anaerobic digestion of sludge: potential and challenges

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Environmental Science and Pollution research 2024年 1-14页

作者： Abubakar, Umar Alfa Lemar, Gul Sanga Bello, Al-Amin Danladi Ishaq, Aliyu Dandajeh, Aliyu Adamu Jagun, Zainab Toyin Houmsi, Mohamad Rajab Department of Water Resources and Environmental Engineering Ahmadu Bello University Kaduna Zaria1045 Nigeria Department of Botany Faculty of Biology Kabul University Kart-E-Char Kabul Afghanistan School of Built Environment Engineering and Computing Leeds Beckett University City Campus Leeds United Kingdom New Era and Development in Civil Engineering Research Group Scientific Research Center Al-Ayen University Thi-Qar Nasiriyah64001 Iraq

This study evaluates models for predicting volatile fatty acid (VFA) concentrations in sludge processing, ranging from classical statistical methods (Gaussian and Surge) to diverse machine learning algorithms (MLAs) such as Decision Tree, XGBoost, CatBoost, LightGBM, Multiple linear regression (MLR), Support vector regression (SVR), AdaBoost, and GradientBoosting. Anaerobic bio-methane potential tests were carried out using domestic wastewater treatment primary and secondary sludge. The tests were monitored over 40 days for variations in pH and VFA concentrations under different experimental conditions. The data observed was compared to predictions from the Gaussian and Surge models, and the MLAs. Based on correlation analysis using basic statistics and regression, the Gaussian model appears to be a consistent performer, with high R2 values and low RMSE, favoring precision in forecasting VFA concentrations. The Surge model, on the other hand, albeit having a high R2, has high prediction errors, especially in dynamic VFA concentration settings. Among the MLAs, Decision Tree and XGBoost excel at predicting complicated patterns, albeit with overfitting issues. This study provides insights underlining the need for context-specific considerations when selecting models for accurate VFA forecasts. Real-time data monitoring and collaborative data sharing are required to improve the reliability of VFA prediction models in AD processes, opening the way for breakthroughs in environmental sustainability and bioprocessing applications. © The Author(s) 2024.

关键词： Anaerobic digestion

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Mobile Payment Adoption: A Systematic Review of the UTAUT Model

Mobile Payment Adoption: A Systematic Review of the UTAUT Mo...

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2019 International Conference on Fourth Industrial Revolution, ICFIR 2019

作者： Al-Saedi, Karrar Al-Emran, Mostafa Abusham, Eimad El-Rahman, Sahar A. Faculty of Computing and Information Technology Sohar University Sohar Oman Applied Computational Civil and Structural Engineering Research Group Faculty of Civil Engineering Ton Duc Thang University Ho Chi Minh City Viet Nam Princess Nourah Bint Abdulrahman University Saudi Arabia Faculty of Engineering at Shoubra Benha University Egypt

ISBN: (纸本)9781728114781

Recently, Mobile payment (M-payment) is fast becoming an essential research field in the information technology domain. Although numerous sectors have adopted the M-payment in different contexts, the factors that affect its adoption is still not apparent. Different information systems (IS) theories/models were developed in order to study the adoption of a specific new technology. One of the most commonly used and validated models in empirical studies is the Unified Theory of Acceptance and Use of Technology (UTAUT) model. Based on the literature, research neglects to review the M-payment adoption studies. The main objective of this study is to systematically review the M-payment adoption studies that involve the UTAUT as the theoretical model. In that, a total of 25 research articles were synthesized and analyzed. The major findings include that 48% of the analyzed studies were conducted in the industrial sectors. Additionally, 80% of the analyzed studies were mainly relied on questionnaire surveys for data collection. Besides, our results revealed that perceived risk and perceived trust are regarded as the most frequent factors that were used to extend the UTAUT to study the M-payment adoption. These findings provide a comprehensive reference for researchers who intend to conduct further research in M-payment. © 2019 IEEE.

关键词： Surveys

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research on integrated management platform of shield construction based on digital twin and application in subway engineering

Research on integrated management platform of shield constru...

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ITA-AITES World Tunnel Congress, WTC 2024

作者： Wang, Xuejian Wang, Jiayuan Zhang, Yuyu Jiang, Sili College of Civil and Transportation Engineering Shenzhen University Shenzhen China Sino-Australia Joint Research Center in BIM and Smart Construction Shenzhen China China Railway South Investment Group Co. Ltd. Shenzhen China

ISBN: (纸本)9781032800424

To effectively address issues in process of shield tunneling for subway construction, including insufficient real-time monitoring, delayed risk response, and limited visualization. This study proposed an integrated management platform of shield construction based on digital twin, analysed remote communication based on cloud service, real-time risk early warning mechanism in TBM operation, as well as integration approach for multi-source information using BIM and GIS technologies. Finally, taking a subway project as an example in case study, the functionalities of platform is demonstrated, such as virtual tunnel and construction simulation, real-time visualization of operating parameters of shield machine, integrated monitoring of shield machine group, visual display of surrounding stratum information, and risk monitoring and early warning in shield construction. The implementation of this platform can improve efficiency, quality and safety of subway shield construction, and also provide valuable insights for the process control of other shield construction projects. © 2024 The Author(s).

关键词： Geographic information systems

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Using immersive video to evaluate future traveller information systems

Using immersive video to evaluate future traveller informati...

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14th World Congress on Intelligent Transport Systems, ITS 2007

作者： Guo, Amy Weihong Blythe, Phil Olivier, Patrick Singh, Pushpendra Ha, Hai Nam Transport Operations Research Group School of Civil Engineering and Geosciences United Kingdom Culture Lab-School of Computing Science Newcastle University Newcastle upon Tyne NE1 7RU United Kingdom

ISBN: (纸本)9781617387777

We present an immersive video system that has been developed for the purpose of evaluating future traveller information system (FTIS), in particular, FTIS scenarios that rely on a pervasive computing infrastructure. Immersive video uses multiple video streams captured from a first person perspective at key locations in a scenario. By dynamically reconstructing a user's visual and aural experiences, the immersive video system creates a lab-based framework that captures a number of the contextual factors of real-world mobile information system use. Graphical user interfaces, displayed on a PDA and a wearable display, are used inthe evaluation. We present both the technical basis of the immersive video system and its application to the study of user perceptions and reactions to pervasive information services.

关键词： Information services

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