Artículos de revistas: "Health aspects of Hydraulic engineering"

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Rui, Zhang, Tian Yahui y Li Helin. "Application of improved radar chart in the health evaluation model of hydraulic gate". Mechanics & Industry 23 (2022): 24. http://dx.doi.org/10.1051/meca/2022014.

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In view of the multi-factor influence of stress, deflection, vibration, corrosion and other factors involved in the state assessment of hydraulic steel gates, established a gate health assessment system including the target layer, criterion layer and indicator layer. A hydraulic health assessment model combining fuzzy analytic hierarchy process and improved radar chart method is proposed. In this method, the fuzzy analytic hierarchy process is used to determine the weight of each index, and then the improved radar chart method is used to evaluate the criterion layer and the target layer respectively, and the gate evaluation level is standardized and drawn into the radar chart. An example of comprehensive evaluation of a radial gate is given, which visually expresses the various factors that affect the gate. While giving the health evaluation result of the gate state, it fully reflects the actual state of all aspects of the gate.

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2

Yang, Yanfang, Lei Ding, Jinhua Xiao, Guinan Fang y Jia Li. "Current Status and Applications for Hydraulic Pump Fault Diagnosis: A Review". Sensors 22, n.º 24 (11 de diciembre de 2022): 9714. http://dx.doi.org/10.3390/s22249714.

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To implement Prognostics Health Management (PHM) for hydraulic pumps, it is very important to study the faults of hydraulic pumps to ensure the stability and reliability of the whole life cycle. The research on fault diagnosis has been very active, but there is a lack of systematic analysis and summary of the developed methods. To make up for this gap, this paper systematically summarizes the relevant methods from the two aspects of fault diagnosis and health management. In addition, in order to further facilitate researchers and practitioners, statistical and comparative analysis of the reviewed methods is carried out, and a future development direction is prospected.

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Cappon, Femke, Tingting Wu, Theodore Papaioannou, Xinli Du, Po-Lin Hsu y Ashraf W. Khir. "Mock circulatory loops used for testing cardiac assist devices: A review of computational and experimental models". International Journal of Artificial Organs 44, n.º 11 (28 de septiembre de 2021): 793–806. http://dx.doi.org/10.1177/03913988211045405.

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Heart failure is a major health risk, and with limited availability of donor organs, there is an increasing need for developing cardiac assist devices (CADs). Mock circulatory loops (MCL) are an important in-vitro test platform for CAD’s performance assessment and optimisation. The MCL is a lumped parameter model constructed out of hydraulic and mechanical components aiming to simulate the native cardiovascular system (CVS) as closely as possible. Further development merged MCLs and numerical circulatory models to improve flexibility and accuracy of the system; commonly known as hybrid MCLs. A total of 128 MCLs were identified in a literature research until 25 September 2020. It was found that the complexity of the MCLs rose over the years, recent MCLs are not only capable of mimicking the healthy and pathological conditions, but also implemented cerebral, renal and coronary circulations and autoregulatory responses. Moreover, the development of anatomical models made flow visualisation studies possible. Mechanical MCLs showed excellent controllability and repeatability, however, often the CVS was overly simplified or lacked autoregulatory responses. In numerical MCLs the CVS is represented with a higher order of lumped parameters compared to mechanical test rigs, however, complex physiological aspects are often simplified. In hybrid MCLs complex physiological aspects are implemented in the hydraulic part of the system, whilst the numerical model represents parts of the CVS that are too difficult to represent by mechanical components per se. This review aims to describe the advances, limitations and future directions of the three types of MCLs.

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Doa’ei, Yaser y Amir Muhammad Jahan. "Application of Artificial Intelligence and Meta-heuristic Algorithms in Civil Health Monitoring Systems". Civil Engineering Journal 4, n.º 7 (1 de agosto de 2018): 1653. http://dx.doi.org/10.28991/cej-03091102.

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After the discovery and manufacturing of every accomplishment, the mankind tends to make it sustainable in terms of different aspects that one of them can be its durability. Nowadays, a science titled “health monitoring” has provided such a consideration in different fields. For example, civil engineering sciences, in various branches, aim to construct various civil engineering accomplishments, followed by the higher goals of making them durable and healthy. The present study tries to give an account about the various study fields like structural engineering, bridge construction, dam construction, hydraulic and on-beach constructions, road engineering and building, water resources management and so on along with the mentioning of the various methods extant for the implementation of such study fields. But, in between, there is an appropriate method that provides such objectives as cost-effectiveness, access to the entire required details, awareness of the civil infrastructures in order to estimate the remained lifetime of the structure in line with the continuation and/or change of the uses. Also, it has high precision and minimally influenced by the environment, so, it can be said that it has very little error in its collection of information. For instance, this method can be used to evaluate the ruination of the structures based on modal properties, which can have static or dynamic foundations such that the current state of the structure is compared to its ideal state to monitor the degree of the structure’s ruination or its soundness. In present study, it was tried to investigate the artificial intelligence science as one of the richest methods possessing all the prerequisites as well as having more traits in common with the various sub-disciplines of civil engineering so that it can be utilized more comprehensively and in a more centralized manner.

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5

Lin, Youli, Farshid Maghool, Arul Arulrajah y Suksun Horpibulsuk. "Engineering Characteristics and Environmental Risks of Utilizing Recycled Aluminum Salt Slag and Recycled Concrete as a Sustainable Geomaterial". Sustainability 13, n.º 19 (24 de septiembre de 2021): 10633. http://dx.doi.org/10.3390/su131910633.

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Recycled aluminum salt slag (RASS) is an industrial by-product generated from the melting of white dross and aluminum scraps during the secondary smelter process. Insufficient knowledge in the aspects of engineering characteristics, and the environmental risks associated with RASS, is the primary barrier to the utilization of RASS as a substitute material for natural quarry materials in the field of geotechnical construction. In this research, comprehensive geotechnical and environmental engineering tests were conducted to evaluate the feasibility of utilizing RASS as a sustainable geomaterial. This was undertaken by comparing the laboratory testing results for RASS with a well-known recycled material, namely recycled concrete aggregate (RCA), and the relevant specifications set forth by the local road authority. The geotechnical engineering assessment included particle size distribution, flakiness index, organic content, pH, particle density, water absorption, modified Proctor compaction, aggregate impact value, Los Angeles (LA) abrasion, hydraulic conductivity, and California bearing ratio (CBR). The CBR results of the RASS samples satisfied the minimum CBR value (>80%) for usage as pavement subbase material in road construction. In addition, the repeated load triaxial (RLT) tests were carried out on the RASS samples to assess the response of the RASS under cyclic loading conditions. Furthermore, a range of chemical tests, consisting of leaching and polycyclic aromatic hydrocarbon tests, were also performed on the RASS to address the environmental concerns. Comparing the chemical test results with the environmental protection authorities’ guidelines provided satisfactory evidence that RASS will not pose any environmental and health issues throughout its service life as a geotechnical construction material.

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6

Shirzad, Akbar y Massoud Tabesh. "New indices for reliability assessment of water distribution networks". Journal of Water Supply: Research and Technology-Aqua 65, n.º 5 (16 de junio de 2016): 384–95. http://dx.doi.org/10.2166/aqua.2016.091.

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This paper presents new indices to evaluate the reliability of water distribution networks (WDNs) usable in the design, planning and management of these networks. Since the pressure-driven analysis (PDA) of WDNs produces more accurate results than the demand-driven analysis, the new indices are proposed based on the PDA. In the proposed measures, nodal pressures, nodal available discharges and the energy loss per unit length of pipes are considered as the main factors influencing the reliability of WDNs. The introduced network reliability index is a combination of two indices named total nodal reliability and total pipe reliability. These indices are equal to the weighted average of all of the nodal and pipe reliabilities, respectively. A sample network is used to evaluate the new proposed index and some of the available indices and to compare their efficiencies in assessing the reliability of WDNs. The results show that the new proposed index is more efficient and outperforms the others. The introduced index is normalized and is independent of the WDN size. This index considers the qualitative aspects of WDNs besides the hydraulic aspects in evaluating reliability.

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7

Rylance, Martin. "Guest Editorial: Unconventional Development Approaches Health Check, and Where We Have To Go". Journal of Petroleum Technology 73, n.º 11 (1 de noviembre de 2021): 10–11. http://dx.doi.org/10.2118/1121-0010-jpt.

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The direction of unconventional developments has been a roller-coaster ride, not only in the realms of financing and profitability, but very much in the technical execution of the well construction and the completion phases, too. This is particularly the case for those aspects relating to the completion and hydraulic fracturing operations. There are few parties, I believe, that would disagree that the drilling com-munity rapidly delivered an extremely coherent and efficient learning curve, something that the completion/fracturing discipline has unfortunately been much slower to achieve. This is not in the least surprising. Effectively extending conventional technologies and focusing on key requirements (i.e., getting from point A to point B) worked well for drilling teams. In a commendable and efficient manner, they were able to readily deploy and incrementally learn in an almost linear fashion. This achieved remarkable delivery records across all unconventional plays. Completions however, namely hydraulic fracturing, has been a very different journey and involves solving a very different problem, one with many more variables, inherent complexities, and multiple degrees of freedom. With each unconventional play potentially being distinct (just as with drilling), these differences can, however, extend to impactful areal trends and features within the plays, as well as subtle variations along individual lateral wellbores. For example, unlike drilling, the form (and even sequence) of an offset wellbore completion can easily affect the completion operations in the current wellbore. It is quite likely that much of the initial misdirection of energy and effort resulted from an overenthusiastic application of conventional planar fracturing technology and knowledge to the unconventional environment. Perhaps the initial lack of effective diagnostic tools and approaches played a role, something that appears to have been understandably addressed in recent years. However, there was also a likely inherent engineering bias in the industry’s fracturing staff engineers. The bulk of the industry engineers had entered unconventionals off at least 2 decades of well understood, well defined, and highly effective physics-based analysis of conventional planar fracturing operations. Indeed, in some areas this fallacy continues. For example, proppant selection is ostensibly performed based on long-established criterion set in place in the 1970s and 1980s, and wholly appropriate to planar fracturing. Whereas the reality is that proppant plays multiple very different roles in unconventionals, bridging, plugging, wedging, diverting, etc. This has led to a “tearing up of the rule book” situation within the sector (that is ongoing) as poorer-quality sands and micro-/nanoproppants find applicability, as well as quality ceramics for a strategic place in the fracture. Yet, you may ask any frac engineer to select proppant for unconventionals and they will almost immediately request data on performance at 2 lb/ft2, as though we are flowing through proppant packs across the entire created geometry. This significantly enhanced level of complexity has led to a general failure of the linear model in terms of effectiveness in progressing optimum completion solutions. As a result, the early years of unconventional completion learning were largely “lost” in this linear way.

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8

Lübken, M., M. Wichern, F. Bischof, S. Prechtl y H. Horn. "Development of an empirical mathematical model for describing and optimizing the hygiene potential of a thermophilic anaerobic bioreactor treating faeces". Water Science and Technology 55, n.º 7 (1 de abril de 2007): 95–102. http://dx.doi.org/10.2166/wst.2007.132.

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Poor sanitation and insufficient disposal of sewage and faeces are primarily responsible for water associated health problems in developing countries. Domestic sewage and faeces are prevalently discharged into surface waters which are used by the inhabitants as a source for drinking water. This paper presents a decentralized anaerobic process technique for handling of such domestic organic waste. Such an efficient and compact system for treating faeces and food waste may be of great benefit for developing countries. Besides a stable biogas production for energy generation, the reduction of bacterial pathogens is of particular importance. In our research we investigated the removal capacity of the reactor concerning pathogens, which has been operated under thermophilic conditions. Faecal coliforms and intestinal enterococci have been detected as indicator organisms for bacterial pathogens. By the multiple regression analysis technique an empirical mathematical model has been developed. The model shows a high correlation between removal efficiency and both, hydraulic retention time (HRT) and temperature. By this model an optimized HRT for defined bacterial pathogens effluent standards can be easily calculated. Thus, hygiene potential can be evaluated along with economic aspects. In this paper not only results for describing the hygiene potential of a thermophilic anaerobic bioreactor are presented, but also an exemplary method to draw the right conclusions out of biological tests with the aid of mathematical tools.

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9

Zheleznyakov, G. V. "Hydraulic and hydrologic aspects of engineering ecology". Hydrotechnical Construction 31, n.º 3 (marzo de 1997): 139–42. http://dx.doi.org/10.1007/bf02767191.

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10

Dey, Ayanangshu. "Hydraulic design and engineering aspects of combined sewers". Proceedings of the Institution of Civil Engineers - Municipal Engineer 166, n.º 4 (diciembre de 2013): 216–29. http://dx.doi.org/10.1680/muen.12.00055.

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11

Kassem, S. A. y H. A. Arafa. "Design aspects of four-nozzle hydraulic servovalves". International Journal of Machine Tools and Manufacture 27, n.º 4 (enero de 1987): 457–68. http://dx.doi.org/10.1016/s0890-6955(87)80018-4.

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12

Walker, James R., Andrea Bertolotti, Reinhard E. Flick y C. Robert Feldmeth. "HYDRAULIC ASPECTS OF WETLAND DESIGN". Coastal Engineering Proceedings 1, n.º 21 (29 de enero de 1988): 198. http://dx.doi.org/10.9753/icce.v21.198.

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Tidal wetland preservation, restoration and creation have become requisites for coastal development projects in the United States. A basic approach to design of tidal wetlands is presented, stressing cooperation between regulatory agencies, biologists, engineers, and developers. Basic principles of wetland functions are explained and presented as criteria for engineering design. A description of wetlands is given to identify biological features relevant to design. Also, some key features of tides are summarized as they affect wetland design. A numerical model was used to demonstrate how tidal wetlands may be designed to conform with criteria developed by the agencies and biologists. This approach has been used on wetland designs in California, but the approach may be applicable to other areas of the world.

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13

Panov, S. I. y N. F. Krivonogova. "Scientific aspects of hydraulic engineering in the Extreme North". Power Technology and Engineering 45, n.º 6 (marzo de 2012): 417–21. http://dx.doi.org/10.1007/s10749-012-0287-z.

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14

Shiralkar, B. S., Md Alamgir y J. G. M. Andersen. "Thermal hydraulic aspects of the SBWR design". Nuclear Engineering and Design 144, n.º 2 (octubre de 1993): 213–22. http://dx.doi.org/10.1016/0029-5493(93)90138-y.

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15

Kovar, P. "Some aspects of hydraulic education in agricultural engineering in Czechoslovakia". La Houille Blanche, n.º 3-4 (junio de 1991): 269–72. http://dx.doi.org/10.1051/lhb/1991026.

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16

Topal, A. Yu, V. V. Firsov, T. S. Usmanov, A. M. Zorin, A. M. Haidar y A. N. Gorin. "Regional aspects of hydraulic fracturing in Udmurtneft OJSC". Neftyanoe khozyaystvo - Oil Industry 4 (2020): 44–48. http://dx.doi.org/10.24887/0028-2448-2020-4-44-48.

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17

Stefanishin, D. V. "Certain theoretical aspects of evaluating aging of hydraulic structures". Hydrotechnical Construction 30, n.º 9 (septiembre de 1996): 534–38. http://dx.doi.org/10.1007/bf02447455.

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18

Csaki, Imre y Ferenc Kalmar. "HYDRAULIC ASPECTS OF SCALING IN GEOTHERMAL ENERGY SYSTEMS". Environmental Engineering and Management Journal 10, n.º 8 (2011): 1155–60. http://dx.doi.org/10.30638/eemj.2011.166.

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19

Fiorillo, Francesco y Peter Malik. "Hydraulic Behavior of Karst Aquifers". Water 11, n.º 8 (29 de julio de 2019): 1563. http://dx.doi.org/10.3390/w11081563.

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The objective of this Special Issue, “Hydraulic Behavior of Karst Aquifers”, is to focus on recent advances in karst hydrogeology in different areas of the world, focusing on topics dealing with the peculiar characteristics of karst aquifers. In particular, thirteen peer-reviewed articles were collected, focusing on hydraulic aspects and their relationship with geological features, geochemical and bacteriological aspects, tunneling and engineering mining inrush, and forecasting water resources and drought occurrences. Overall, these contributions describe several aspects of karst aquifers and are of great value for water resource management and protection.

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20

Guo, Yanbao, Min Zhang, Hui Yang, Deguo Wang, Melvin A. Ramos, Travis Shihao Hu y Quan Xu. "Friction Challenge in Hydraulic Fracturing". Lubricants 10, n.º 2 (18 de enero de 2022): 14. http://dx.doi.org/10.3390/lubricants10020014.

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Hydraulic fracturing has become one of the most popular techniques for exploring sustainable energy sources. However, friction is associated with the entire fracturing process, presenting significant challenges for development. Facing the huge friction challenges, this review is elaborated in the following three aspects: (1) the fundamentals of hydraulic fracturing, including three aspects of rock fracture mechanism, fracturing fluid, and proppant; (2) the friction challenges in hydraulic fracturing, which mainly exist in friction along the path and friction near wellbore; (3) hydraulic fracturing drag reduction technologies, which are considered proppant segment plug, fracturing fluid viscosity enhancement, and proppant surface modification technologies. Therefore, we should not only understand the challenges in hydraulic fracturing but also know how to mitigate them. Additionally, we call for a strong focus on environmentally friendly, green friction-reducing technologies for oil and gas fields in the future development of the fracturing industry.

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Deaconescu, Tudor y Andrea Deaconescu. "Key Aspects in Addressing Friction in Coaxial Hydraulic Sealing Systems". Advanced Materials Research 690-693 (mayo de 2013): 1988–91. http://dx.doi.org/10.4028/www.scientific.net/amr.690-693.1988.

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Ensuring energy-efficient operation of a hydraulic cylinder is determined also by minimizing the friction forces caused by mobile sealing systems. The nature of friction in a sealing system on one hand, and the systems sealing ability, on the other, are determined by the thickness of the fluid film built up at the contact between seal and sealed surface. The paper presents an evaluation of the hydrodynamic pressures that causes the occurrence of a fluid-filled gap between the elements of a coaxial sealing system, as well as the influence of various parameters on its size.

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22

Alzoubi, Mahmoud A., Minghan Xu, Ferri P. Hassani, Sébastien Poncet y Agus P. Sasmito. "Artificial ground freezing: A review of thermal and hydraulic aspects". Tunnelling and Underground Space Technology 104 (octubre de 2020): 103534. http://dx.doi.org/10.1016/j.tust.2020.103534.

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23

Guiny, Eliane, D. Alan Ervine y John D. Armstrong. "Hydraulic and Biological Aspects of Fish Passes for Atlantic Salmon". Journal of Hydraulic Engineering 131, n.º 7 (julio de 2005): 542–53. http://dx.doi.org/10.1061/(asce)0733-9429(2005)131:7(542).

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Vaikasas, Saulius y Mindaugas Stankevičius. "SOME ASPECTS OF MODELING BED PROCESSES IN TRAINED RIVERS". JOURNAL OF ENVIRONMENTAL ENGINEERING AND LANDSCAPE MANAGEMENT 12, n.º 1 (31 de marzo de 2004): 30–37. http://dx.doi.org/10.3846/16486897.2004.9636812.

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Physical modeling of sediment transport and morphology in rivers as well as wastewater dilution processes are closely related to the modeling of macro turbulent fluctuations. The physical modeling of hydraulic macro turbulent fluctuations is complicated and underestimated. The study of turbulent flow structure and verification as well as model calibration is required in this case. Some methods of model verification by means of kinematics and turbulent coefficients scaling αKa, α x and αkare presented in the paper. Experience in hydraulic modeling of bed processes in the Neris and Nemunas rivers contributed to the viable results. As laboratory tests showed, after the scales of the Nemunas bed had been distorted 12 times, the turbulence of modeled flow increased causing 3 times more intensive wastewater dilution processes in a physical model of the Nemunas bed. When modeling the bed processes of the Neris in Vilnius in a hydraulic model with the scale distorted 6,7 times, it was determined that a more intensive turbulence caused a 25 % thinner bed soil layer and nearly 3 times higher velocity of vertical turbulent flow. This was considered when calculating the results obtained in a model into natural ones and when choosing proper means for designing riverbed hydraulic structures.

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25

Lee, Wei y Chun Guang Wang. "Study Control System Based on Creep Test in High Density Baler". Advanced Materials Research 139-141 (octubre de 2010): 1624–27. http://dx.doi.org/10.4028/www.scientific.net/amr.139-141.1624.

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Hydraulic transmission system controls hydraulic cylinder forward and backward movement freely, in order to achieve high density hydraulic baler work circulation. Creep test required hydraulic system to output constant stress, and study creep tests can not be completed when used succeeding the electrical contact style in the past time. The system used programmable logic controller (PLC) to instead of succeeding the electrical contact style and realized freely forward and backward movement of hydraulic cylinder, electro-hydraulic proportional relief valve can adjust hydraulic system and make it stepless pressure regulation and then degree of automation and reliability in hydraulic control system to be improved. This paper introduces aspects: including the selection, hardware configuration and program of PLC, meanwhile, giving specific realization method. Through the control system to study creep test in hydraulic baler, adopting the National Instrument (NI) company's multi-channel data acquisition card, which type is USB-6251,applying Labview8.2 to write data acquisition program on my own, the versatility and flexibility of system was verified, which was able to complete creep test successfully.

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Coleman, Nichola J., Kunle Awosanya y John W. Nicholson. "Aspects of thein vitrobioactivity of hydraulic calcium (alumino)silicate cement". Journal of Biomedical Materials Research Part A 90A, n.º 1 (junio de 2009): 166–74. http://dx.doi.org/10.1002/jbm.a.32070.

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GREEN, STANLEY J. "Thermal, Hydraulic, and Corrosion Aspects of PWR Steam Generator Problems". Heat Transfer Engineering 9, n.º 1 (enero de 1988): 19–68. http://dx.doi.org/10.1080/01457638808939660.

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28

Selvadurai, A. P. S. y Y. Ichikawa. "Some aspects of air-entrainment on decay rates in hydraulic pulse tests". Engineering Geology 165 (octubre de 2013): 38–45. http://dx.doi.org/10.1016/j.enggeo.2013.05.023.

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SIWULSKI, TOMASZ, URSZULA WARZYNSKA, KATARZYNA PANOWSKA y MATEUSZ WOLTER. "IMPROVING THE EFFICIENCY OF A ROCK BREAKER HYDRAULIC WORKING SYSTEM BY CHANGING THE STRUCTURE OF THE HYDRAULIC SYSTEM". MM Science Journal 2022, n.º 3 (27 de septiembre de 2022): 5738–47. http://dx.doi.org/10.17973/mmsj.2022_10_2022067.

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The amount of energy losses in hydraulic systems, determined directly by the efficiency parameter, becomes one of the basic aspects related to the design of these systems. Recently, reducing the energy consumption of hydraulic drives has become one of the most important factors in, and sometimes even the main reason for, development works focused on hydrostatic drive systems in newly designed and already deployed types of machines. The article presents an approach to improve the efficiency of such a hydraulic system based on the analytical model and also includes a case study of redesigning a hydrostatic drive system in a stationary rock breaking machine. The analysis of the calculation results showed benefits resulting from two different concepts of modifying hydraulic systems with an aim at reducing their energy consumption.

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Kouhikamali, R., Z. FallahRamezani y M. Asgari. "Investigation of thermo-hydraulic design aspects in optimization of MED plants". Desalination and Water Treatment 51, n.º 28-30 (agosto de 2013): 5501–8. http://dx.doi.org/10.1080/19443994.2013.769657.

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Bilen, Branislav, Branka Bilen-Katic y Marko Zerjal. "Some Naval Architectural Problems in Underwater Coal Mining". Marine Technology and SNAME News 31, n.º 02 (1 de abril de 1994): 116–22. http://dx.doi.org/10.5957/mt1.1994.31.2.116.

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This paper presents a solution for a propulsion system that provides perfect speed control and maneuverability for a survey launch used in the process of underwater coal mining. First, mining aspects of coal exploitation are explained. There is also a brief technical description of a cutting wheel suction dredger, including specifications for dredging equipment. The important role of the survey launch in underwater mining procedures is outlined and technical specifications of an installed indirect diesel-hydraulic drive are given. A qualitative comparison between the diesel-hydraulic and the other conventional propulsion systems is made. Finally, some operating parameters of the diesel-hydraulic propulsion system are given through a number of diagrams recorded during trials.

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Jin, Xi, Ying He Jiang y Jian Hua Jin. "Interception Ratio Optimal Selection Aided by Micro-Scope Hydraulic and Quality Simulation". Advanced Materials Research 113-116 (junio de 2010): 119–25. http://dx.doi.org/10.4028/www.scientific.net/amr.113-116.119.

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Optimal selection of interception ratio of combined sewer systems is a problem of comparison in technical and economical aspects. Using the simulation result of SWMM, the relationship between pollutant removal efficiency and interception ratio can be quantified, so the technical index of interception ratio selection can be obtained. Regarding of pollutant removal efficiency and construction cost as functions of interception ratio, two objective functions of optimization model can be obtained. By solving this optimization model, the balance between technical and economical aspects can be realized at the result interception ratio. Tested by the case sewer system, an optimal result can be obtained by this optimization model and it’s solving methodology.

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ShengQing, Yang, Ji Hong, Li SenLin, Sun Fei y Wang SuYan. "Prediction and verification for the models of temperature rising by medium bubbles in hydraulic system". Advances in Mechanical Engineering 14, n.º 3 (marzo de 2022): 168781322210854. http://dx.doi.org/10.1177/16878132221085431.

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In order to obtain the influence of the medium bubble contents on temperature rising characteristics of a hydraulic system, the working hydraulic system of a wheel loader was taken as the research object. By carrying out the comparison experiments of the hydraulic system with and without de-aeration devices on a 5-ton wheel loader, the air bubble contents and concerning temperatures were obtained. To identify the factors which have impact on temperature rising of the hydraulic system, the head chamber of boom cylinder is taken to analyze, and the temperature rising expression in a volume were deduced. By the utilization of the thermal hydraulic library, combining with mechanism and control libraries on AMESim simulation platform, the integrated simulation model of the whole system was established and verified, meanwhile, the simulation was carried out from aspects in different air contents and initial chamber temperatures. From the simulation, the prediction models of the air contents to temperature rising, and the pressures to temperature rising were predicted. Finally, the correctness of the prediction models are verified by experiment data and showing good results, which can be used to enrich and improve the calculation and evaluation methods of heat generation to any other hydraulic systems.

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Skworcow, P., D. Paluszczyszyn y B. Ulanicki. "Pump schedules optimisation with pressure aspects in complex large-scale water distribution systems". Drinking Water Engineering and Science 7, n.º 1 (16 de junio de 2014): 53–62. http://dx.doi.org/10.5194/dwes-7-53-2014.

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Abstract. This paper considers optimisation of pump and valve schedules in complex large-scale water distribution networks (WDN), taking into account pressure aspects such as minimum service pressure and pressure-dependent leakage. An optimisation model is automatically generated in the GAMS language from a hydraulic model in the EPANET format and from additional files describing operational constraints, electricity tariffs and pump station configurations. The paper describes in details how each hydraulic component is modelled. To reduce the size of the optimisation problem the full hydraulic model is simplified using module reduction algorithm, while retaining the nonlinear characteristics of the model. Subsequently, a nonlinear programming solver CONOPT is used to solve the optimisation model, which is in the form of Nonlinear Programming with Discontinuous Derivatives (DNLP). The results produced by CONOPT are processed further by heuristic algorithms to generate integer solution. The proposed approached was tested on a large-scale WDN model provided in the EPANET format. The considered WDN included complex structures and interactions between pump stations. Solving of several scenarios considering different horizons, time steps, operational constraints, demand levels and topological changes demonstrated ability of the approach to automatically generate and solve optimisation problems for a variety of requirements.

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35

Albarhoum, M. "Thermal-hydraulic and safety aspects of UO2 fuel for low-power reactors". Progress in Nuclear Energy 53, n.º 4 (mayo de 2011): 354–60. http://dx.doi.org/10.1016/j.pnucene.2011.01.004.

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36

Dassanayake, Darshana Tharindra y Hocine Oumeraci. "HYDRAULIC STABILITY OF COASTAL STRUCTURES MADE OF GEOTEXTILE SAND CONTAINERS (GSCS): EFFECT OF ENGINEERING PROPERTIES OF GSCS". Coastal Engineering Proceedings 1, n.º 33 (14 de diciembre de 2012): 55. http://dx.doi.org/10.9753/icce.v33.structures.55.

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Due to their numerous advantages, Geotextile Sand Containers (GSCs /or Geobags) are getting increasingly popular as an alternative to conventional hard (rock / concrete) structures. This study attempts to evaluate the significance of the most important engineering properties and their influence on the hydraulic stability of GSC-structures. The most important engineering properties of GSCs are the mechanical properties of the geotextile material, the sand fill ratio, type of the fill material, the interface friction, etc. In fact most of these properties will affect the deformation of GSCs and the movement of sand inside the container. More importantly, these properties are interrelated. The importance of these aspects has been highlighted in many studies and projects worldwide. However, the knowledge about the influence of the sand fill ratio, the properties of fill material and the interface friction of GSCs on the hydraulic stability of GSC-structure is still very poor. Therefore, a series of experimental investigations were conducted, in order to better understand their effect on the hydraulic stability and to develop a computational tool and simple formulae for the hydraulic stability of different types of GSC-structures subject to different wave conditions. This paper contains some selected findings from these experimental investigations, which were performed at Leichtweiss-Institute for Hydraulic Engineering and Water Resources (LWI). Furthermore, the sensitivity of each GSC property on the hydraulic stability and new hydraulic stability nomograms are presented, including the implications for the engineering practice.

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37

Wolfe, Raymond W., Sami F. Masri y John Caffrey. "Some structural health monitoring approaches for nonlinear hydraulic dampers". Journal of Structural Control 9, n.º 1 (2002): 5–18. http://dx.doi.org/10.1002/stc.6.

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38

Li, Ke y Zongxuan Sun. "Hydraulic Free Piston Engine Enabled by Active Motion Control". Mechanical Engineering 135, n.º 06 (1 de junio de 2013): S7—S9. http://dx.doi.org/10.1115/1.2013-jun-6.

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This article explores various functional aspects of hydraulic free piston engine (FPE) enabled by action motion control. Given the potential for high efficiency and flexibility, the FPE is well suited for mobile applications such as on-road vehicles and off-road heavy machinery. The advantage of the active motion controller lies in its ability to precisely track and shape the piston trajectory. FPE has a great potential for energy saving and emission control, but its reliable operation is limited by the complex dynamic coupling among the engine subsystems and the lack of the crankshaft. This inherent technical barrier for FPE could be overcome by active control with today’s sensing, actuation and computing technologies. A prototype hydraulic FPE is used to demonstrate the capabilities of active piston motion control. Experimental results demonstrate the feasibility and promise of the technology. Engine power control will be combined with piston motion control in the future to achieve a wider range of engine operation and higher engine efficiency.

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39

Shi, Hu, Kun Tan, Boyang Zhang y Wenqiao Liu. "Review on Research Progress of Hydraulic Powered Soft Actuators". Energies 15, n.º 23 (29 de noviembre de 2022): 9048. http://dx.doi.org/10.3390/en15239048.

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Soft actuators have received extensive attention in robotics and smart device applications due to their distinctive dexterity and compliance. Among them, hydraulic soft actuators play an important role in the area because they have much higher specific power and power density than other types such as pneumatic soft actuators. Nevertheless, the deformation of flexible materials in soft actuators brings about inherent hysteresis and nonlinearity, which severely hinders them from producing the desired movement in the presence of advanced control strategies. In this paper, previous research efforts made to enhance the driving capability and actuation efficiency of hydraulic soft actuators are illustrated and analyzed from the three aspects of architecture, materials, and control strategy. Meanwhile, the issues and challenges that have emerged when developing hydraulic soft actuators are discussed. Finally, the potential future development of hydraulic powered soft actuators is discussed.

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40

Chapuis, Robert P. "Controlling the quality of groundwater parameters: some examples". Canadian Geotechnical Journal 32, n.º 1 (1 de febrero de 1995): 172–77. http://dx.doi.org/10.1139/t95-014.

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Hydraulic head, gradient, hydraulic conductivity, transmissivity, and storativity are input data that should be collected according to applicable codes and standards. These must be defined without ambiguity, and they must be mutually compatible. Feasibility studies and the design of facilities are based on these data. A firm providing professional services in hydrogeology can improve quality in this area only by examining the reasons for poor quality: the reasons are not found in standards or codes. This paper provides examples to illustrate variou aspects of the work to be done to control the quality of groundwater seepage parameters. The paper has a narrow focus within the context of total quality management. Key words : groundwater, parameters, quality control.

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41

Shabalinskaya, L. A. "Tribological aspects of the use of water-based liquids in the hydraulic systems of vehicles". Russian Engineering Research 27, n.º 10 (octubre de 2007): 682–85. http://dx.doi.org/10.3103/s1068798x07100061.

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42

Zhabin, Dmitryi V., Viktor N. Sokov y Dmitryi Y. Zemlyanushnov. "Foam Concrete through Electric Technology". Advanced Materials Research 860-863 (diciembre de 2013): 1189–92. http://dx.doi.org/10.4028/www.scientific.net/amr.860-863.1189.

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The article considers possible production of foam concrete through an intensive method of processing the foam mass providing for the completion of physical, chemical and structural formation processes. The physical aspects of temperature gradients arising in the foam mass under the effect of combined hydraulic-and-heating field of forces are shown.

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43

Riazantsev, O. y V. Shylin. "Hydrotechnical construction, water engineering and water technologies: some modern issues and training of professionals". New Collegium 1, n.º 103 (30 de marzo de 2021): 29–34. http://dx.doi.org/10.30837/nc.2021.1.29.

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The article considers modern problems and problems that currently exist in hydraulic engineering and hydropower, problems of land and water resources. And also problems of training of experts. able to solve these problems Recently, the problems caused by existing large hydraulic structures are increasingly mentioned. The main problem is that the nodes of hydraulic structures often form artificial reservoirs of a large plane. It often happens that the depths of reservoirs are insignificant. This situation is very unsatisfactory because the land is used irrationally. which is a valuable resource and has a high cost and can be used effectively for agriculture. Creation of hydraulic structures, complexes of hydraulic structures significantly change the hydrological, biological. salt and thermal regimes of the river on which they are built, the regime of groundwater movement, cause climate change in the surrounding areas. Cascades of hydraulic structures have a special influence. As an example, we can cite the Dnieper cascade of hydroelectric power plants and compare the area of its reservoirs and the amount of electricity generated by its power plants with the world's largest hydroelectric power plants. In addition, shallow water bodies cause a significant deterioration in water quality. And since reservoirs are often a source of water supply for settlements and industrial enterprises, this situation is controversial. Intensive construction of hydraulic structures and their complexes took place during the twentieth century, many of them exhausted their resources and needed either reconstruction or decommissioning. The reasons for this state of affairs are the development of technology, the emergence and development of other alternative energy sources for thermal and nuclear power plants, other than hydraulic. Also, since the construction of many buildings, approaches to determining their profitability and efficiency have changed. Aspects of training specialists in hydraulic engineering and water engineering, able to solve these problems of the industry today, and those that will face them in the near future are considered. The ability of a competent professional to anticipate the consequences of any action must be an integral part of it. Attention is drawn to the need to apply conceptually new approaches to solving problems of construction of new hydraulic and hydropower facilities, operation and reconstruction of existing facilities.

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44

Crawford, Mark. "Fracturing Rocks to Unlock New Oil". Mechanical Engineering 135, n.º 12 (1 de diciembre de 2013): 24–29. http://dx.doi.org/10.1115/1.2013-dec-1.

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This article discusses various uses and benefits of hydraulic fracturing technology in the field of oil industry. Engineers continue to increase hydraulic fracturing efficiency by developing better multistage stimulation systems. These systems enable treatment of many intervals along a horizontal wellbore with a minimum number of pull-outs, or even in a single continuous operation. Many key advances in drilling and hydrofracturing have resulted from sophisticated modeling programs. Mechanical engineers play key roles in many aspects of hydrofracturing, especially the design of better down-hole tools, new materials, and improved numerical models. With the advances in modeling and real-time measurement, operators can deliver just the right type of fracking pressure, exactly where they want it, and repeat the process as needed, either in the same well, one that parallels it, or one that radiates out from the same central drill pad. The experts feel that if the world wishes to fully use its oil-and-gas resources, it will go hand-in-hand with hydraulic fracturing.

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45

Popov, A. N., R. A. Ismakov, F. N. Yangirov, A. R. Yakhin y I. D. Abusal Yusef. "Theoretical preconditions for modeling wellbore stability and predicting hydraulic fracturing". SOCAR Proceedings, SI1 (30 de junio de 2021): 41–49. http://dx.doi.org/10.5510/ogp2021si100508.

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One of the complex technological tasks in the process of drilling is to ensure the stability of the wellbore walls, as well as their modeling for further forecasting the state of the wellbore and the likelihood of hydraulic fracturing. This is due to the fact that most of the complications and factors affecting the equilibrium state of the wall are associated with external influences. The article discusses the mechanical and partially hydraulic aspects of solving the described problems associated with modeling the stability of the wellbore walls and predicting hydraulic fracturing. As a result of calculations, the necessary data are obtained for making a decision on the density of the drilling fluid for drilling the considered interval of rocks. The assumed model of the porous rock and the given calculation formulas make it possible to fully evaluate the influence of the formation fluid pressure on the mechanical processes in the rocks when they are opened by a well. Keywords: hydraulic fracturing; blade bit; steel ball-shaped toothed bit; polycrystalline diamond bit; laser drilling; impact rope drilling; rotary drilling.

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46

Massoudi, Mehrdad. "Mathematical Modeling of Fluid Flow and Heat Transfer in Petroleum Industries and Geothermal Applications 2020". Energies 14, n.º 16 (19 de agosto de 2021): 5104. http://dx.doi.org/10.3390/en14165104.

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In this Special Issue, all aspects of fluid flow and heat transfer in geothermal applications, including the ground heat exchanger, conduction, and convection in porous media, are considered. The emphasis here is on mathematical and computational aspects of fluid flow in conventional and unconventional reservoirs, geothermal engineering, fluid flow and heat transfer in drilling engineering, and enhanced oil recovery (hydraulic fracturing, steam-assisted gravity drainage (SAGD), CO2 injection, etc.) applications.

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47

Pacheco, Admilson Da Penha, Renato Filipe Faria Henriques y Paulo Marcelo Vieira Ribeiro. "Technical and scientific aspects of dams in Brazil: a theoretical approach". Ambiente e Agua - An Interdisciplinary Journal of Applied Science 15, n.º 5 (3 de septiembre de 2020): 1. http://dx.doi.org/10.4136/ambi-agua.2552.

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The safety of a dam is the result of a series of factors, including structural, geotechnical, hydraulic, operational and environmental aspects. In Brazil, Law No. 12.334 of September 2010 establishes the National Dam Safety Policy, which requires safety reports and monitoring inspections for existing dams. The inspection comprises a set of devices installed on the dam, which are used to assess the structural behavior based on performance parameters of the structure, such as displacements, flows, stresses, slopes and others. Dam auscultation procedures, historically, have been performed since the 1950s. Since then, there have been significant advances in instrumentation and dam auscultation methods. This work presents a theoretical approach on technical and scientific aspects of dams in Brazil, based on a state-of-the-art literature review, involving auscultation of dams in the context of design codes, concepts, instrumentation, safety, procedures and monitoring methods.

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48

Holmes, P. G. "Operational Aspects of Doha South Sewage Treatment Works". Water Science and Technology 21, n.º 10-11 (1 de octubre de 1989): 1477–88. http://dx.doi.org/10.2166/wst.1989.0344.

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Extensions to Doha South Sewage Treatment Works provided preliminary, primary, secondary and tertiary treatment for a design population of 100,000 persons, producing disinfected effluent for use in restricted municipal irrigation with digested sludge being conditioned and dewatered by plate pressing. Secondary treatment was designed to be non-nitrifying surface aeration activated sludge, and experience was gained in preventing partial nitrification by strict control of dissolved oxygen residuals. The works operated successfully to ensure a high quality of final effluent despite hydraulic overloading of 1.85 times design DWF and disruptions caused by contracts to further extend the plant. Treatment costs reflected the emphasis placed upon the purchase of imported chemicals and spare parts to ensure continued operation. Operating experience confirmed the suitability of the chosen processes to achieve intended effluent and sludge qualities.

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49

Reventós, F., L. Batet, C. Llopis, C. Pretel y I. Sol. "Thermal-Hydraulic Analysis Tasks for ANAV NPPs in Support of Plant Operation and Control". Science and Technology of Nuclear Installations 2008 (2008): 1–13. http://dx.doi.org/10.1155/2008/153858.

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Thermal-hydraulic analysis tasks aimed at supporting plant operation and control of nuclear power plants are an important issue for the Asociación Nuclear Ascó-Vandellòs (ANAV). ANAV is the consortium that runs the Ascó power plants (2 units) and the Vandellòs-II power plant. The reactors are Westinghouse-design, 3-loop PWRs with an approximate electrical power of 1000 MW. The Technical University of Catalonia (UPC) thermal-hydraulic analysis team has jointly worked together with ANAV engineers at different levels in the analysis and improvement of these reactors. This article is an illustration of the usefulness of computational analysis for operational support. The contents presented were operational between 1985 and 2001 and subsequently changed slightly following various organizational adjustments. The paper has two different parts. In the first part, it describes the specific aspects of thermal-hydraulic analysis tasks related to operation and control and, in the second part, it briefly presents the results of three examples of analyses that were performed. All the presented examples are related to actual situations in which the scenarios were studied by analysts using thermal-hydraulic codes and prepared nodalizations. The paper also includes a qualitative evaluation of the benefits obtained by ANAV through thermal-hydraulic analyses aimed at supporting operation and plant control.

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50

Milbradt, P. y T. Schonert. "A holistic approach and object-oriented framework for eco-hydraulic simulation in coastal engineering". Journal of Hydroinformatics 10, n.º 3 (1 de mayo de 2008): 201–14. http://dx.doi.org/10.2166/hydro.2008.029.

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The consideration of biological processes in hydro- and morphodynamic models is an important challenge for numerical simulation in coastal engineering. Eco-hydraulic aspects will play a major role in engineering tools and planning processes for the design of coastal works. Vegetation greatly affects the hydro- and morphodynamic models in coastal zones. Most hydrodynamic numerical models do not consider influences by ecological factors. This paper focuses on the presentation of an object-oriented holistic framework for eco-hydraulic simulation. The numerical approximation is performed by a stabilized finite element method for hydro- and morphodynamic processes, to solve the related partial differential equations, and by a cell-oriented model for the simulation of ecological processes, which is based on a fuzzy rule system. The fundamental differences between these model paradigms require special transfer and coupling methods. Case studies on seagrass prediction in the North Sea around the island of Sylt show the main effects and influences on changed hydro- and morphodynamic processes and demonstrate the applicability of the coupled finite element fuzzy cell-based approach in eco-hydraulic modeling.

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