Journal articles: 'Hydraulic architecture'

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Sperry, John. "Hydraulic architecture of palms." Giornale botanico italiano 129, no. 1 (January 1995): 482–90. http://dx.doi.org/10.1080/11263509509436166.

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Vanderborght, Jan, Valentin Couvreur, Felicien Meunier, Andrea Schnepf, Harry Vereecken, Martin Bouda, and Mathieu Javaux. "From hydraulic root architecture models to macroscopic representations of root hydraulics in soil water flow and land surface models." Hydrology and Earth System Sciences 25, no. 9 (September 6, 2021): 4835–60. http://dx.doi.org/10.5194/hess-25-4835-2021.

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Abstract. Root water uptake is an important process in the terrestrial water cycle. How this process depends on soil water content, root distributions, and root properties is a soil–root hydraulic problem. We compare different approaches to implement root hydraulics in macroscopic soil water flow and land surface models. By upscaling a three-dimensional hydraulic root architecture model, we derived an exact macroscopic root hydraulic model. The macroscopic model uses the following three characteristics: the root system conductance, Krs, the standard uptake fraction, SUF, which represents the uptake from a soil profile with a uniform hydraulic head, and a compensatory matrix that describes the redistribution of water uptake in a non-uniform hydraulic head profile. The two characteristics, Krs and SUF, are sufficient to describe the total uptake as a function of the collar and soil water potential, and water uptake redistribution does not depend on the total uptake or collar water potential. We compared the exact model with two hydraulic root models that make a priori simplifications of the hydraulic root architecture, i.e., the parallel and big root model. The parallel root model uses only two characteristics, Krs and SUF, which can be calculated directly following a bottom-up approach from the 3D hydraulic root architecture. The big root model uses more parameters than the parallel root model, but these parameters cannot be obtained straightforwardly with a bottom-up approach. The big root model was parameterized using a top-down approach, i.e., directly from root segment hydraulic properties, assuming a priori a single big root architecture. This simplification of the hydraulic root architecture led to less accurate descriptions of root water uptake than by the parallel root model. To compute root water uptake in macroscopic soil water flow and land surface models, we recommend the use of the parallel root model with Krs and SUF computed in a bottom-up approach from a known 3D root hydraulic architecture.

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Leifeld, Roland, Milos Vukovic, and Hubertus Murrenhoff. "Hydraulic Hybrid Architecture for Excavators." ATZoffhighway worldwide 9, no. 3 (May 25, 2016): 44–49. http://dx.doi.org/10.1007/s41321-016-0523-9.

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Tiboni, Monica. "Power Drive Architectures for Industrial Hydraulic Axes: Energy-Efficiency-Based Comparative Analysis." Applied Sciences 13, no. 18 (September 6, 2023): 10066. http://dx.doi.org/10.3390/app131810066.

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In hydraulic systems, energy dissipation can be significant. The pressure losses that can occur in the hydraulic circuit, which are influenced by the adopted drive architecture, result in power consumption that is often significantly higher than that required by the mechanical system. This paper presents a comparative study of the energy efficiency of five common drive architectures in industrial hydraulic axes. The analysis is applied to a variable speed and force hydraulic blanking press, a fairly common industrial system, e.g., in the manufacture of semi-finished brass products. Standard, regenerative, high–low, variable-displacement pumps and variable speed drive configurations for a fixed-displacement pump were analyzed and compared. In each case, an appropriate and optimized sizing of the different components of the system was performed, and then the energy consumption was estimated for a load cycle common to all the considered cases. The results show that the choice of the power generation architecture of the hydraulic system has a very significant impact on the energy efficiency and consequently on the operating costs and the carbon footprint. The performed quantification of the potential energy efficiency of the considered drive architectures can be very useful in helping to make energy-conscious decisions.

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Carvalho, Mónica R., Robert Turgeon, Thomas Owens, and Karl J. Niklas. "The hydraulic architecture of Ginkgo leaves." American Journal of Botany 104, no. 9 (September 2017): 1285–98. http://dx.doi.org/10.3732/ajb.1700277.

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Hacke, Uwe G. "Irradiance-induced changes in hydraulic architecture." Botany 92, no. 6 (June 2014): 437–42. http://dx.doi.org/10.1139/cjb-2013-0200.

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The ability to acclimate to a range of light regimes is important, given that shady understory habitats can receive only a fraction of the light available at the top of the canopy. Sun and shade leaves are known to differ in their set of biochemical and morphological characteristics. In recent years, much has also been learned about the effect of shade on xylem structure and function. Several studies found that shaded plants had narrower xylem conduits than plants growing in full sun. Among the most notable responses induced by shade is a shift of xylem vulnerability to cavitation. Shaded plants are typically more vulnerable to cavitation than plants exposed to full light. This appears to coincide with the construction of weaker intervessel and intertracheid pit membranes in shade. Before entering and after exiting the xylem, water moves through living cells in roots and leaves, respectively. This nonvascular pathway can be modified by aquaporins. Rapid changes in root and leaf hydraulic conductance in response to changes in light and transpirational demand have been described. The role of aquaporins in these responses is discussed.

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Chen, Cai, Xu Wang, and Changming Zhou. "Architecture design for civil aircraft hydraulic system." Journal of Physics: Conference Series 2457, no. 1 (March 1, 2023): 012009. http://dx.doi.org/10.1088/1742-6596/2457/1/012009.

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Abstract The hydraulic system is a highly complex system for civil aircraft. System Engineering is a method to solve complex and comprehensive problems. To reduce the development risk, this paper establishes a hydraulic system architecture design model based on system engineering using system ideas and analysis methods. With this model, several aspects of hydraulic system architecture design are discussed, including input, requirements analysis, functional analysis, system synthesis, and system balance.

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Gaiola, Andrea, Barbara Zardin, Paolo Casoli, Massimo Borghi, Francesca Mazzali, Francesco Pintore, and Stefano Fiorati. "The Hydraulic Power Generation and Transmission on Agricultural Tractors: feasible architectures to reduce dissipation and fuel consumption – Part I." E3S Web of Conferences 197 (2020): 07009. http://dx.doi.org/10.1051/e3sconf/202019707009.

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This paper is aimed at investigating the benefits in terms of energy efficiency of new electro-hydraulic architectures for power distribution systems of a medium-size agricultural tractor, with a focus on the hydraulic high-pressure circuit. The work is part of a wider industrial research project called TASC (Smart and Clean Agricultural Tractors [1]). Traditional and alternative architectures have been modelled and energetically compared through simulation, using a lumped parameter approach. Experimental data previously acquired have been used to validate the models and to replicate real working conditions of the machine in the simulation environment. A typical on-field manoeuvre has been used as duty cycle, to perform an effective energetic analysis. The standard hydraulic circuit is a multi-users load sensing system that uses a single variable displacement pump to feed steering, trailer brake and auxiliary utilities in that order. The key idea of the proposed solutions is the separation of steering from the other implements, to optimize the entire energy management. In particular, the paper investigates new and flexible solutions for the auxiliary utilities, including an electro-hydraulic load sensing architecture with variable pump margin, an electronic flow matching and flow sharing architecture, and an electronic strategy for automatic pressure compensation. The simulation results show that good energy saving can be achieved with the alternative architectures, so that physical prototyping of the most promising solutions will be realized as next step of the project.

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Christoffersen, Bradley O., Manuel Gloor, Sophie Fauset, Nikolaos M. Fyllas, David R. Galbraith, Timothy R. Baker, Bart Kruijt, et al. "Linking hydraulic traits to tropical forest function in a size-structured and trait-driven model (TFS v.1-Hydro)." Geoscientific Model Development 9, no. 11 (November 24, 2016): 4227–55. http://dx.doi.org/10.5194/gmd-9-4227-2016.

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Abstract. Forest ecosystem models based on heuristic water stress functions poorly predict tropical forest response to drought partly because they do not capture the diversity of hydraulic traits (including variation in tree size) observed in tropical forests. We developed a continuous porous media approach to modeling plant hydraulics in which all parameters of the constitutive equations are biologically interpretable and measurable plant hydraulic traits (e.g., turgor loss point πtlp, bulk elastic modulus ε, hydraulic capacitance Cft, xylem hydraulic conductivity ks,max, water potential at 50 % loss of conductivity for both xylem (P50,x) and stomata (P50,gs), and the leaf : sapwood area ratio Al : As). We embedded this plant hydraulics model within a trait forest simulator (TFS) that models light environments of individual trees and their upper boundary conditions (transpiration), as well as providing a means for parameterizing variation in hydraulic traits among individuals. We synthesized literature and existing databases to parameterize all hydraulic traits as a function of stem and leaf traits, including wood density (WD), leaf mass per area (LMA), and photosynthetic capacity (Amax), and evaluated the coupled model (called TFS v.1-Hydro) predictions, against observed diurnal and seasonal variability in stem and leaf water potential as well as stand-scaled sap flux. Our hydraulic trait synthesis revealed coordination among leaf and xylem hydraulic traits and statistically significant relationships of most hydraulic traits with more easily measured plant traits. Using the most informative empirical trait–trait relationships derived from this synthesis, TFS v.1-Hydro successfully captured individual variation in leaf and stem water potential due to increasing tree size and light environment, with model representation of hydraulic architecture and plant traits exerting primary and secondary controls, respectively, on the fidelity of model predictions. The plant hydraulics model made substantial improvements to simulations of total ecosystem transpiration. Remaining uncertainties and limitations of the trait paradigm for plant hydraulics modeling are highlighted.

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Ishii, Hiroaki, Wakana Azuma, Ayumi Shiraki, and Keiko Kuroda. "Hydraulic Architecture and Function of Tall Trees." Journal of the Japanese Forest Society 99, no. 2 (2017): 74–83. http://dx.doi.org/10.4005/jjfs.99.74.

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Darlington, Alan B., and Michael A. Dixon. "The hydraulic architecture of roses (Rosa hybrida)." Canadian Journal of Botany 69, no. 4 (April 1, 1991): 702–10. http://dx.doi.org/10.1139/b91-095.

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The presence of an abscission zone in the stem of greenhouse roses (Rosa hybrida) between the vegetative and reproductive components was verified. This led to a description of the hydraulic architecture of the rose stem. The structural aspects of the xylem conducting system in stem, abscission zone and peduncle were examined to define their relative roles in the delivery of water via the stem to the transpiring plant surfaces and the extent to which their functional capacity may be influenced by environmental variables such as humidity. The stem exhibited a highly developed xylem with many large-diameter tracheary elements. Contrary to this the distal segment of the peduncle was poorly vascularized. The remainder of the peduncle, which included the abscission zone, was a transition between these two extremes. The abscission zone was a site of reduced hydraulic conductance that was not due to a reduction in the number or size of xylem conduits but to changes in the alignment of the elements. The variable conductances across the abscission zone and peduncle regions may play an important role in floral development and the response of the plant to water stress. Rose plants grown at constantly high humidity (77% RH) did not exhibit significantly different internal anatomical features of the xylem conducting system relative to roses grown in ambient, uncontrolled humidity (30 to 60% RH). Key words: abscission zone, hydraulic conductance, humidity.

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Martínez-Vilalta, Jordi, Anna Sala, and Josep Piñol. "The hydraulic architecture of Pinaceae – a review." Plant Ecology (formerly Vegetatio) 171, no. 1/2 (2004): 3–13. http://dx.doi.org/10.1023/b:vege.0000029378.87169.b1.

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Zolfaghar, Sepideh, Randol Villalobos-Vega, Melanie Zeppel, and Derek Eamus. "The hydraulic architecture of Eucalyptus trees growing across a gradient of depth-to-groundwater." Functional Plant Biology 42, no. 9 (2015): 888. http://dx.doi.org/10.1071/fp14324.

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Heterogeneity in water availability acts as an important driver of variation in plant structure and function. Changes in hydraulic architecture represent a key mechanism by which adaptation to changes in water availability can be expressed in plants. The aim of this study was to investigate whether differences in depth-to-groundwater influence the hydraulic architecture of Eucalyptus trees in remnant woodlands within mesic environments. Hydraulic architecture of trees was examined in winter and summer by measuring the following traits: Huber value (HV: the ratio between sapwood area and leaf area), branch hydraulic conductivity (leaf and sapwood area specific), sapwood density, xylem vulnerability (P50 and Pe) and hydraulic safety margins across four sites where depth-to-groundwater ranged from 2.4 to 37.5 m. Huber value increased significantly as depth-to-groundwater increased. Neither sapwood density nor branch hydraulic conductivity (sapwood and leaf area specific) varied significantly across sites. Xylem vulnerability to embolism (represented by P50 and Pe) in both seasons was significantly and negatively correlated with depth-to-groundwater. Hydraulic safety margins increased with increasing depth-to-groundwater and therefore trees growing at sites with deeper water tables were less sensitive to drought induced embolism. These results showed plasticity in some, but not all, hydraulic traits (as reflected in HV, P50, Pe and hydraulic safety margin) in response to increase in depth-to-groundwater in a mesic environment.

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Hochberg, Uri, Asfaw Degu, Tanya Gendler, Aaron Fait, and Shimon Rachmilevitch. "The variability in the xylem architecture of grapevine petiole and its contribution to hydraulic differences." Functional Plant Biology 42, no. 4 (2015): 357. http://dx.doi.org/10.1071/fp14167.

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Grapevine cultivars possess large variability in their response to water availability, and are therefore considered as a good model to study plant hydraulic adjustments. The current research compared the petiole anatomy of two grapevine (Vitis vinifera L.) cultivars, Shiraz and Cabernet Sauvignon, in respect to hydraulic properties. Hydraulic differences between the cultivar petioles were tested over 3 years (2011–2013). Anatomical differences, hydraulic conductivity and embolism were tested under terminal drought conditions. Additionally, xylem differentiation under well watered (WW) and water deficit (WD) conditions was compared. Shiraz was shown to possess larger xylem vessels that resulted in a significantly higher theoretical specific hydraulic conductivity (Kts), leaf hydraulic conductivity (Kleaf) and maximal petiole hydraulic conductivity (Kpetiole). Under WD, smaller vessels were developed, more noticeably in Shiraz. Results confirmed a link between petiole hydraulic architecture and hydraulic behaviour, providing a simple mechanistic explanation for the higher transpiration rates commonly measured in Shiraz. Smaller xylem vessels in Cabernet Sauvignon could imply on its adaptation to WD, and explains its better performances under such conditions.

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McCulloh, K. A., and D. R. Woodruff. "Linking stomatal sensitivity and whole-tree hydraulic architecture." Tree Physiology 32, no. 4 (April 1, 2012): 369–72. http://dx.doi.org/10.1093/treephys/tps036.

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Zotz, G. "Water relations and hydraulic architecture of woody hemiepiphytes." Journal of Experimental Botany 48, no. 315 (October 1, 1997): 1825–33. http://dx.doi.org/10.1093/jexbot/48.315.1825.

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Zotz, Gerhard, Sandra Patiño, and Melvin T. Tyree. "Water relations and hydraulic architecture of woody hemiepiphytes." Journal of Experimental Botany 48, no. 10 (1997): 1825–33. http://dx.doi.org/10.1093/jxb/48.10.1825.

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Cruiziat, Pierre, Herv� Cochard, and Thierry Am�glio. "Hydraulic architecture of trees: main concepts and results." Annals of Forest Science 59, no. 7 (November 2002): 723–52. http://dx.doi.org/10.1051/forest:2002060.

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Dindorf, Ryszard Filip. "Functional Safety of the Hydraulic Drive Control System of a Tracked Undercarriage." Archives of Automotive Engineering – Archiwum Motoryzacji 103, no. 1 (March 28, 2024): 21–37. http://dx.doi.org/10.14669/am/178310.

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In the study, the functional safety of the hydraulic drive control system of a tracked undercarriage used as a mobile platform for a robotic bricklaying system (RBS) was evaluated. Hazards and risks caused by the hydraulic drive control system of the rubber track undercarriage were identified. The schematic diagram and main components of the conventional hydraulic drive control system of a tracked undercarriage are presented. The functions and parameters of the components of the hydraulic power and control system are discussed. In a conventional hydraulic drive, the safety function is fulfilled by failsafe brakes built into the hydraulic motors. In order for RBS to work safely on the construction site, it was necessary to introduce an advanced safe control system for the hydraulic drive of the tracked undercarriage. An advanced safe control system for the hydraulic drive of the tracked undercarriage includes hydraulic control valves with safety functions, a two-channel category 3 safe control architecture, and a safety microcontroller. SISTEMA software tools were utilized to determine safety functions and calculate their specifications. Based on the specifications of the safety function associated with the category of the safety control architecture, the achievable performance level of the hydraulic drive control system for the tracked chassis was determined.

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Wang, Long Hui, and Yong Wang. "Design of Direct Drive Electro-Hydraulic Actuator Based on Internet of Things Technology." Advanced Materials Research 945-949 (June 2014): 1601–5. http://dx.doi.org/10.4028/www.scientific.net/amr.945-949.1601.

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Direct drive electro-hydraulic actuator is a new type of hydraulic transmission with easy maintenance and high efficiency, which has been widely used in municipal engineering (such as water pipe network, gas pipe network), nuclear power plants, and other occasions. For these applications, we designed the electro-hydraulic valve actuator based on Internet of things technology (IOT for short). This paper introduces the mechanical structure and the working principle of the direct-drive electro-hydraulic valve actuator, analyzes IOT architecture. Detailed design was carried on according to the IOT architecture and related experiments have been done. The actuator can automatically, accurately control valve opening, be monitored by PC remotely, display device real-time information through LCD and be operated by touch screen.

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Li, Wei Min, Tie Jun Li, and Shu Fen Liu. "Key Technology and System Implementation of Distributed Collaborative Design in Hydraulic System." Applied Mechanics and Materials 16-19 (October 2009): 1377–81. http://dx.doi.org/10.4028/www.scientific.net/amm.16-19.1377.

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The state-of-art of collaborative hydraulic system design and the necessity to carry on collaborative hydraulic system design are summarized. The architecture and implementation methodology of Web-based collaborative product design system are presented, with some key techniques of implementing collaborative hydraulic system design being discussed in detail.

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Nie, Chunhui, Yimin Shao, Chris K. Mechefske, Dingqiang Peng, and Xiaodong Yang. "Pipe architecture optimization of the parallel Hydraulic-pneumatic hybrid system using a hydraulic transformer." Energy Conversion and Management 266 (August 2022): 115858. http://dx.doi.org/10.1016/j.enconman.2022.115858.

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He, Xunan, YuanLi Kang, and Yannian Hui. "Modeling and Analysis of Different Architecture for Civil Aircraft Hydraulic System." Journal of Physics: Conference Series 2068, no. 1 (October 1, 2021): 012028. http://dx.doi.org/10.1088/1742-6596/2068/1/012028.

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Abstract For the evaluation of civil aircraft hydraulic system, Fuel Consumption is a very important index. However, there is no effective method to perform analysis for different architecture. This paper proposes that taking fuel weight penalty as a major mathmatical modeling method to analysis traditional architecture and more electric architecture. The result shows that the fuel consumption of more electric architecture is less than traditional architecture.

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Mallak, Ahlam, and Madjid Fathi. "Sensor and Component Fault Detection and Diagnosis for Hydraulic Machinery Integrating LSTM Autoencoder Detector and Diagnostic Classifiers." Sensors 21, no. 2 (January 9, 2021): 433. http://dx.doi.org/10.3390/s21020433.

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Anomaly occurrences in hydraulic machinery might lead to massive system shut down, jeopardizing the safety of the machinery and its surrounding human operator(s) and environment, and the severe economic implications following the faults and their associated damage. Hydraulics are mostly placed in ruthless environments, where they are consistently vulnerable to many faults. Hence, not only are the machines and their components prone to anomalies, but also the sensors attached to them, which monitor and report their health and behavioral changes. In this work, a comprehensive applicational analysis of anomalies in hydraulic systems extracted from a hydraulic test rig was thoroughly achieved. First, we provided a combination of a new architecture of LSTM autoencoders and supervised machine and deep learning methodologies, to perform two separate stages of fault detection and diagnosis. The two phases were condensed by—the detection phase using the LSTM autoencoder. Followed by the fault diagnosis phase represented by the classification schema. The previously mentioned framework was applied to both component and sensor faults in hydraulic systems, deployed in the form of two in-depth applicational experiments. Moreover, a thorough literature review of related work from the past decade, for autoencoders related fault detection and diagnosis in hydraulic systems, was successfully conducted in this study.

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Mallak, Ahlam, and Madjid Fathi. "Sensor and Component Fault Detection and Diagnosis for Hydraulic Machinery Integrating LSTM Autoencoder Detector and Diagnostic Classifiers." Sensors 21, no. 2 (January 9, 2021): 433. http://dx.doi.org/10.3390/s21020433.

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Anomaly occurrences in hydraulic machinery might lead to massive system shut down, jeopardizing the safety of the machinery and its surrounding human operator(s) and environment, and the severe economic implications following the faults and their associated damage. Hydraulics are mostly placed in ruthless environments, where they are consistently vulnerable to many faults. Hence, not only are the machines and their components prone to anomalies, but also the sensors attached to them, which monitor and report their health and behavioral changes. In this work, a comprehensive applicational analysis of anomalies in hydraulic systems extracted from a hydraulic test rig was thoroughly achieved. First, we provided a combination of a new architecture of LSTM autoencoders and supervised machine and deep learning methodologies, to perform two separate stages of fault detection and diagnosis. The two phases were condensed by—the detection phase using the LSTM autoencoder. Followed by the fault diagnosis phase represented by the classification schema. The previously mentioned framework was applied to both component and sensor faults in hydraulic systems, deployed in the form of two in-depth applicational experiments. Moreover, a thorough literature review of related work from the past decade, for autoencoders related fault detection and diagnosis in hydraulic systems, was successfully conducted in this study.

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Decombeix, Anne-Laure, Anaïs Boura, and Alexandru M. F. Tomescu. "Plant hydraulic architecture through time: lessons and questions on the evolution of vascular systems." IAWA Journal 40, no. 3 (July 2019): 387–420. http://dx.doi.org/10.1163/22941932-40190254.

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ABSTRACTStudies of anatomically preserved fossils provide a wealth of information on the evolution of plant vascular systems through time, from the oldest evidence of vascular plants more than 400 million years ago to the rise of the modern angiosperm-dominated flora. In reviewing the key contributions of the fossil record, we discuss knowledge gaps and major outstanding questions about the processes attending the evolution of vascular systems. The appearance and diversification of early vascular plants in the late Silurian-Devonian was accompanied by the evolution of different types of tracheids, which initially improved the hydraulics of conduction but had less of an effect on mechanical support. This was followed in the Devonian and Carboniferous by an increase in complexity of the organization of primary vascular tissues, with different types of steles evolving in response to mechanical, hydraulic, and developmental regulatory constraints. Concurrently, secondary vascular tissues, such as wood, produced by unifacial or bifacial cambia are documented in a wide array of plant groups, including some that do not undergo secondary growth today. While wood production has traditionally been thought to have evolved independently in different lineages, accumulating evidence suggests that this taxonomic breadth reflects mosaic deployment of basic developmental mechanisms, some of which are derived by common ancestry. For most of vascular plant history, wood contained a single type of conducting element: tracheids (homoxyly). However, quantitative (e.g. diameter and length) and qualitative (e.g. pitting type) diversity of these tracheids allowed various taxa to cover a broad range of hydraulic properties. A second type of conducting elements, vessels, is first documented in an extinct late Permian (c. 260 Ma) group. While the putative hydraulic advantages of vessels are still debated, wood characterized by presence of vessels (heteroxyly) would become the dominant type, following the diversification of angiosperms during the Cretaceous.

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Cao, Xun, Yan Li, Xin-Jun Zheng, Jiang-Bo Xie, and Zhong-Yuan Wang. "An Inherent Coordination between the Leaf Size and the Hydraulic Architecture of Angiosperm Trees." Forests 13, no. 8 (August 14, 2022): 1287. http://dx.doi.org/10.3390/f13081287.

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Leaf veins are the continuation of twigs, and the hydraulic system of a leaf is part of, and the continuation of, the hydraulic architecture of a tree. Previous studies have demonstrated that the vessel diameter of the widest part at the tree base is tightly related to the total stem length of a tree. Here, we demonstrate that: the vessel diameter of the narrowest part at the distal end of the tree (the terminal twigs) is closely correlated to the leaf size for an angiosperm tree. Consequently, the basic feature of the hydraulic system of an angiosperm tree may be predicted by two simple parameters: the stem length (or tree height) and the leaf size, with the tree height predicting the size of the widest vessel at the tree base and the leaf size predicting the size of the narrowest vessel at the terminal trig. Namely, there is an inherent coordination between the leaf size and the hydraulic architecture of the angiosperm tree. As leaves are replacing themselves every year, their responses to climate are direct and immediate, while the woody part of a tree is there for years and more, and thus can only respond passively to climate change. This may cause a mismatch between the woody part and leaf part of the hydraulic system, and thus endanger the hydraulic coordination between leaves and the woody part.

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Cisneros-de la Cruz, Diana J., Laura Yáñez-Espinosa, Casandra Reyes-García, Roberth Us-Santamaría, and José Luis Andrade. "Hydraulic architecture of seedlings and adults of Rhizophora mangle L. in fringe and scrub mangrove." Botanical Sciences 100, no. 2 (December 14, 2021): 370–82. http://dx.doi.org/10.17129/botsci.2906.

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Background: Mangrove plant species have distinctive anatomical and physiological responses to cope with a wide range of salinities and inundations. These strategies pertain a safe and efficient water use and transport, essential for survival. Questions: How are the anatomical and physiological attributes of the hydraulic architecture of seedlings and adults of Rhizophora mangle? what are the changes in hydraulic architecture of seedlings and adults of R. mangle in contrasting microenvironments? Studied species: Rhizophora mangle L. (Rhizophoraceae). Study site and dates: Scrub and fringe mangroves in Ria Celestún Biosphere Reserve, during the rainy season of 2013 (July to October). Methods: Hydraulic conductivity and leaf water potential, as well as xylem vessel density, length, transversal and radial diameter, and area were measured for seedlings and adults from both sites. The prevailing environmental conditions (soil water potential, salinity, photon flux density, air temperature and relative humidity) were also characterized. Results: A safer hydraulic conduction system, with narrow and more grouped vessels, was observed in seedlings than in adults of R. mangle in both sites. Adult individuals from the scrub mangrove, in the hyper saline microenvironment, had a safer hydraulic conduction system than adults in the fringe mangrove. Conclusions: The seedling stage of R. mangle showed a safer hydraulic system than adults in both types of mangroves. However, over time this hydraulic conduction system could become more efficient or remain safe depending on the microenvironment in which individuals are growing.

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Rockwell, Fulton E., and N. Michele Holbrook. "Leaf Hydraulic Architecture and Stomatal Conductance: A Functional Perspective." Plant Physiology 174, no. 4 (June 14, 2017): 1996–2007. http://dx.doi.org/10.1104/pp.17.00303.

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Jyske, Tuula, and Teemu Hölttä. "Comparison of phloem and xylem hydraulic architecture inPicea abiesstems." New Phytologist 205, no. 1 (August 15, 2014): 102–15. http://dx.doi.org/10.1111/nph.12973.

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Carvalho, Mónica R., Robert Turgeon, Thomas Owens, and Karl J. Niklas. "The scaling of the hydraulic architecture in poplar leaves." New Phytologist 214, no. 1 (January 5, 2017): 145–57. http://dx.doi.org/10.1111/nph.14385.

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Peña, Oscar R., and Michael J. Leamy. "An efficient architecture for energy recovery in hydraulic elevators." International Journal of Fluid Power 16, no. 2 (May 4, 2015): 83–98. http://dx.doi.org/10.1080/14399776.2015.1055991.

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TYREE, MELVIN T., and FRANK W. EWERS. "The hydraulic architecture of trees and other woody plants." New Phytologist 119, no. 3 (November 1991): 345–60. http://dx.doi.org/10.1111/j.1469-8137.1991.tb00035.x.

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Zwieniecki, M. A., P. J. Melcher, C. K. Boyce, L. Sack, and N. M. Holbrook. "Hydraulic architecture of leaf venation in Laurus nobilis L." Plant, Cell & Environment 25, no. 11 (October 29, 2002): 1445–50. http://dx.doi.org/10.1046/j.1365-3040.2002.00922.x.

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Poyatos, R., J. Martínez-Vilalta, J. Čermák, R. Ceulemans, A. Granier, J. Irvine, B. Köstner, et al. "Plasticity in hydraulic architecture of Scots pine across Eurasia." Oecologia 153, no. 2 (April 24, 2007): 245–59. http://dx.doi.org/10.1007/s00442-007-0740-0.

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NARDINI, ANDREA, and FRANCO PITT. "Drought resistance ofQuercus pubescensas a function of root hydraulic conductance, xylem embolism and hydraulic architecture." New Phytologist 143, no. 3 (September 1999): 485–93. http://dx.doi.org/10.1046/j.1469-8137.1999.00476.x.

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Jaumann, Stefan, and Kurt Roth. "Soil hydraulic material properties and layered architecture from time-lapse GPR." Hydrology and Earth System Sciences 22, no. 4 (April 25, 2018): 2551–73. http://dx.doi.org/10.5194/hess-22-2551-2018.

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Abstract. Quantitative knowledge of the subsurface material distribution and its effective soil hydraulic material properties is essential to predict soil water movement. Ground-penetrating radar (GPR) is a noninvasive and nondestructive geophysical measurement method that is suitable to monitor hydraulic processes. Previous studies showed that the GPR signal from a fluctuating groundwater table is sensitive to the soil water characteristic and the hydraulic conductivity function. In this work, we show that the GPR signal originating from both the subsurface architecture and the fluctuating groundwater table is suitable to estimate the position of layers within the subsurface architecture together with the associated effective soil hydraulic material properties with inversion methods. To that end, we parameterize the subsurface architecture, solve the Richards equation, convert the resulting water content to relative permittivity with the complex refractive index model (CRIM), and solve Maxwell's equations numerically. In order to analyze the GPR signal, we implemented a new heuristic algorithm that detects relevant signals in the radargram (events) and extracts the corresponding signal travel time and amplitude. This algorithm is applied to simulated as well as measured radargrams and the detected events are associated automatically. Using events instead of the full wave regularizes the inversion focussing on the relevant measurement signal. For optimization, we use a global–local approach with preconditioning. Starting from an ensemble of initial parameter sets drawn with a Latin hypercube algorithm, we sequentially couple a simulated annealing algorithm with a Levenberg–Marquardt algorithm. The method is applied to synthetic as well as measured data from the ASSESS test site. We show that the method yields reasonable estimates for the position of the layers as well as for the soil hydraulic material properties by comparing the results to references derived from ground truth data as well as from time domain reflectometry (TDR).

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Borodychev, V. V., M. N. Lytov, and A. S. Razin. "Algorithm for computer modeling of combined irrigation systems hydraulic parameters." IOP Conference Series: Earth and Environmental Science 843, no. 1 (November 1, 2021): 012052. http://dx.doi.org/10.1088/1755-1315/843/1/012052.

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Abstract A feature of combined irrigation systems is the integration of various technologies and methods of irrigation with the implementation of such a possibility on the basis of a single technical system. The hydraulic calculation of such systems is more complicated, since it is assumed that it is possible to implement various modes of operation, which differ by the combination of hydraulic parameters. The operating modes are determined by the combination of the involved irrigation technologies carried out simultaneously. The research has proposed an algorithm for the computer simulation of combined irrigation systems hydraulic parameters. The algorithm implements the principle of step-by-step calculation and formation of statistical screenshots of the hydraulic parameters of the system based on the basic calculated dependencies of classical hydraulics. Static screens can be performed at any time interval, which allows to assess the dynamics of the process under changing external conditions, as well as study the system under different operating modes. The algorithm has built an ingenious system of objects identification, making it possible not only to verify the uniquely defined knots of stems section, but also to organize serial search nodal points in accordance with the architecture of the construction of hydro-reclamation systems.

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David, Teresa S., Jorge S. David, Clara A. Pinto, Jan Cermak, Valery Nadezhdin, and Nadezhda Nadezhdina. "Hydraulic connectivity from roots to branches depicted through sap flow: analysis on a Quercus suber tree." Functional Plant Biology 39, no. 2 (2012): 103. http://dx.doi.org/10.1071/fp11185.

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The topology of the xylem network is likely to affect the transport of water, propagation of embolism and plant survival and growth. Few studies have been conducted on the hydraulics of the entire water pathway in trees. We evaluated the hydraulic connections from roots to branches in a mature Quercus suber L. tree, through sap flow responses upon branch severing. Sap flow was recorded in branches, stem and roots by the heat field deformation (HFD) method. Results showed that roots, except for the taproot, were hydraulically connected to all branches, but the rest of the tree (stem, branches and taproot) was highly sectored. In the large roots that showed an integrated response to branch severing, the outer xylem was preferentially connected to the same side branch and the inner xylem to the opposite branch. The hydraulic sectoriality in branches, stem and taproot may be regarded as an adaptive trait to water stress. The integrated hydraulic structure of roots is advantageous under patchy soil conditions, but may allow the spread of root diseases. The HFD sap flow method proved extremely useful to calculate xylem flux connectivity between different organs of a large tree, providing a comprehensive picture of its hydraulic architecture.

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Zilka, Vladimir, Pavol Bisták, and Peter Kurcik. "Hydraulic Plant Remote Laboratory." International Journal of Online and Biomedical Engineering (iJOE) 4 (July 15, 2008): 69–73. http://dx.doi.org/10.3991/ijoe.v4i0.587.

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In this paper we present a three tank hydraulic system and possibilities how it can be used for the purpose of remote laboratories. The concept of our remote laboratory is based on client â?? server architecture. We compare two different approaches of remote control. First one uses a Java Server application implemented together with a control algorithm on the server side. In this case the control algorithm is realized in the Matlab/Simulink environment. There is necessary to exchange data between the Matlab and the Java Server application what is done through the COM technology. The second approach uses PC-independent network card which runs its own TCP server and the control algorithm is implemented on client side.

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Ghandour, Maysoon, Subhi Jleilaty, Naima Ait Oufroukh, Serban Olaru, and Samer Alfayad. "Real-Time EtherCAT-Based Control Architecture for Electro-Hydraulic Humanoid." Mathematics 12, no. 9 (May 3, 2024): 1405. http://dx.doi.org/10.3390/math12091405.

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Electro-hydraulic actuators have witnessed significant development over recent years due to their remarkable abilities to perform complex and dynamic movements. Integrating such an actuator in humanoids is highly beneficial, leading to a humanoid capable of performing complex tasks requiring high force. This highlights the importance of safety, especially since high power output and safe interaction seem to be contradictory; the greater the robot’s ability to generate high dynamic movements, the more difficult it is to achieve safety, as this requires managing a large amount of motor energy before, during, and after the collision. No matter what technology or algorithm is used to achieve safety, none can be implemented without a stable control system. Hence, one of the main parameters remains the quality and reliability of the robot’s control architecture through handling a huge amount of data without system failure. This paper addresses the development of a stable control architecture that ensures, in later stages, that the safety algorithm is implemented correctly. The optimum control architecture to utilize and ensure the maximum benefit of electro-hydraulic actuators in humanoid robots is one of the important subjects in this field. For a stable and safe functioning of the humanoid, the development of the control architecture and the communication between the different components should adhere to some requirements such as stability, robustness, speed, and reduced complexity, ensuring the easy addition of numerous components. This paper presents the developed control architecture for an underdeveloped electro-hydraulic actuated humanoid. The proposed solution has the advantage of being a distributed, real-time, open-source, modular, and adaptable control architecture, enabling simple integration of numerous sensors and actuators to emulate human actions and safely interact with them. The contribution of this paper is an enhancement of the updated rate compared to other humanoids by 20% and by 40 % in the latency of the master. The results demonstrate the potential of using EtherCAT fieldbus and open-source software to develop a stable robot control architecture capable of integrating safety and security algorithms in later stages.

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Harayama, Hisanori, Mitsutoshi Kitao, Evgenios Agathokleous, and Atsushi Ishida. "Effects of major vein blockage and aquaporin inhibition on leaf hydraulics and stomatal conductance." Proceedings of the Royal Society B: Biological Sciences 286, no. 1904 (June 5, 2019): 20190799. http://dx.doi.org/10.1098/rspb.2019.0799.

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The density and architecture of leaf veins determine the network and efficiency of water transport within laminae and resultant leaf gas exchange and vary widely among plant species. Leaf hydraulic conductance ( K leaf ) can be regulated by vein architecture in conjunction with the water channel protein aquaporin. However, our understanding of how leaf veins and aquaporins affect leaf hydraulics and stomatal conductance ( g s ) remains poor. By inducing blockage of the major veins and inhibition of aquaporin activity using HgCl 2 , we examined the effects of major veins and aquaporins on K leaf and g s in species with different venation types. A vine species, with thick first-order veins and low vein density, displayed a rapidly declined g s with high leaf water potential in response to vein blockage and a greatly reduced K leaf and g s in response to aquaporin inhibition, suggesting that leaf aquaporins are involved in isohydric/anisohydric stomatal behaviour. Across species, the decline in K leaf and g s due to aquaporin inhibition increased linearly with decreasing major vein density, possibly indicating that a trade-off function between vein architecture (apoplastic pathway) and aquaporin activity (cell-to-cell pathway) affects leaf hydraulics.

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Lo Gullo, Maria A., Fabio Raimondo, Alessandro Crisafulli, Sebastiano Salleo, and Andrea Nardini. "Leaf hydraulic architecture and water relations of three ferns from contrasting light habitats." Functional Plant Biology 37, no. 6 (2010): 566. http://dx.doi.org/10.1071/fp09303.

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Leaf hydraulic architecture and water relations of three fern species were measured. The species selected were adapted either to deeply shaded (Woodwardia radicans), moderately shaded (Dryopteris affinis) or moderately sunny (Polystichum setiferum) habitats, as confirmed by microclimatic measurements performed in the field. Leaf water potential (Ψleaf) was lower and leaf conductance to water vapour (gL) was higher in P. setiferum than in the shade-adapted ferns. Leaf osmotic potential and water potential at the turgor loss point were lower in the sun-adapted species than in the other ferns. Leaf hydraulic resistance (Rleaf) was lowest in P. setiferum and Rleaf was correlated with gL across species. Low Rleaf was coordinated with low rachis hydraulic resistance (Rrachis). Low values of Rrachis in P. setiferum were not due to the presence of wide xylem conduits as checked on the basis of anatomical measurements, but to increased radial permeability of vascular bundles. This was a consequence of the absence of endodermis surrounding the vascular bundles in P. setiferum, which was observed in the rachis of shade-adapted species. We conclude that hydraulic adjustment of fern fronds is a key component of adaptation of pteridophytes to contrasting light habitats.

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ANTONOV, A. S., O. D. RUBIN, and E. M. KOBOCHKINA. "IMPROVEMENT OF THE INFORMATION AND DIAGNOSTIC SYSTEM OF THE SOFTWARE AND HARDWARE COMPLEX TO ENSURE THE SECURITY OF GTS." Prirodoobustrojstvo, no. 1 (2021): 73–78. http://dx.doi.org/10.26897/1997-6011-2021-1-73-78.

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The need to create a single unified information and diagnostic system to ensure the safe operation of hydraulic structures is caused by the requirements of the Federal Law ”On the safety of hydraulic structures“ (No. 117-FZ). At the current moment, the systems used are heterogeneous and are being developed according to the requirements of operation and expert organizations, while the uniformity of terminology and approach to assessing the state of objects is not ensured. The purpose of this work is to define approaches and to develop architecture for a unified information and diagnostic system. At the same time, it is necessary to ensure the performance of the minimum set of functions necessary for a comprehensive analysis of the state of hydraulic structures. There is given a description of the architecture and basic set of functions of the information system which make it possible to monitor the state of hydraulic structures. The systematization of the functionality of the existing information systems has been carried out, on the basis of the analysis the optimal composition of the minimum number of functions which provide control over the safe operation of hydraulic structures has been developed.

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Gupta, Chetali, Madeline J. Sverdlove, and Newell R. Washburn. "Molecular architecture requirements for polymer-grafted lignin superplasticizers." Soft Matter 11, no. 13 (2015): 2691–99. http://dx.doi.org/10.1039/c4sm02675f.

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Superplasticizers are a class of anionic polymer dispersants used to inhibit aggregation in hydraulic cement. We demonstrate that polymer-grafted lignin can be a highly effective superplasticizer when the molecular architecture is based on a lignin core with a hydrophilic polymer corona.

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Sangsing, Krissada, Hervé Cochard, Poonpipope Kasemsap, Sornprach Thanisawanyangkura, Kumut Sangkhasila, Eric Gohet, and Philippe Thaler. "Is growth performance in rubber (Hevea brasiliensis) clones related to xylem hydraulic efficiency?" Canadian Journal of Botany 82, no. 7 (July 1, 2004): 886–91. http://dx.doi.org/10.1139/b04-083.

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Hydraulic efficiency, xylem pressure, and stomatal conductance were measured in two Hevea clones having contrasting growth performances in their immature phase. Hydraulic efficiency was estimated by the xylem resistance on a leaf area basis on stem, petiole segments, and whole branches. The fast-growing clone exhibited significantly higher xylem efficiency, higher stomatal conductance, and higher xylem pressure. The difference in xylem pressure between the two clones was quantitatively consistent with the differences in hydraulic resistance and leaf transpiration rates. Our results suggest that variations in xylem efficiency may explain variations in stomatal conductance and xylem pressure, and hypothetically, growth performance between Hevea clones.Key words: xylem, hydraulic conductance, hydraulic architecture, water relations, rubber tree, Hevea.

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McClenahan, Kate, Catriona Macinnis-Ng, and Derek Eamus. "Hydraulic architecture and water relations of several species at diverse sites around Sydney." Australian Journal of Botany 52, no. 4 (2004): 509. http://dx.doi.org/10.1071/bt03123.

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Seasonal comparisons of leaf water potential, root biomass, hydraulic architecture, xylem embolism and xylem dimensions were made for eight woody species in four diverse habitats (mangroves, coastal heathland, ridge-top woodland and river-flat woodland). In most comparisons, pre-dawn and minimum leaf water potentials were lower in winter than in summer, a result attributed to lower rainfall and a smaller root biomass in winter than in summer. Branch hydraulic conductivities (per unit transverse area, sapwood area or leaf area) were generally larger in summer than in winter across all species in all habitats. An inverse relationship between Huber value and conductivity was observed across all four habitats. Increased solar radiation and evaporative demand in the summer was associated with an increased percentage loss of xylem conductance arising from embolism, compared with winter. These results are discussed in the context of patterns and relationships among water relations, microclimate and hydraulic architecture.

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Stump, Patrick, Nathan Keller, and Andrea Vacca. "Energy Management of Low-Pressure Systems Utilizing Pump-Unloading Valve and Accumulator." Energies 12, no. 23 (November 21, 2019): 4423. http://dx.doi.org/10.3390/en12234423.

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In the context of improving energy efficiency and fuel consumption of mobile hydraulic equipment, it is important to analyze all the sources of power loss occurring within the hydraulic systems. While plenty of analyses have been performed on the working implements and the main transmission systems, very little attention has been paid to low-pressure (LP) systems until recently. LP systems are required on closed-circuit hydraulic systems to replenish losses, provide cooling flow, and maintain a pilot pressure necessary to operate hydraulic control valves and variable displacement units. It is shown that these circuits, which are often thought to have minimal impact on power consumption, actually cause significant, continuous power loss. A new method of power savings in these circuits is investigated through management of charge pump flow by application of an accumulator-sense pump-unloading (ASPU) valve. This work further proposes the combination of a split LP architecture with an ASPU valve. Three systems are simulated using Simcenter Amesim® and MATLAB/Simulink®. Using realistic duty cycles and unit loss models on a circuit for mobile off-road hydraulic equipment, it is shown that a standard LP system can consume about 5 kW of power. Power savings of up to 65% over a standard LP system are demonstrated by the proposed architecture.

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Khatibi, Rahman, Dave Jackson, John Curtin, Chris Whitlow, Adri Verwey, and Paul Samuels. "Vision statement on open architecture for hydraulic modelling software tools." Journal of Hydroinformatics 6, no. 1 (January 1, 2004): 57–74. http://dx.doi.org/10.2166/hydro.2004.0005.

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This paper identifies the philosophy of open architecture as a feasible vision capable of transforming modelling software packages into living products. This vision, invoked within the specific context of software production in the field of flood forecasting within the Environment Agency, promotes the emerging requirements and consensus of users, academics and software producers. In the past, the philosophy of closed architecture dominated the use, development resources and investment in modelling systems by producers and users. As closed architecture encourages the development of monolithic software products with limited scope for innovation by third parties, investments often do not return the value of their full potential. A consensus is emerging that this is no longer tenable. The time is right: for the producers of hydraulic and hydrologic software tools to move from the culture of ‘doing things better’ to ‘doing things better and doing better things’; for users to design their own systems through assembling off-the-shelf software products; and for academics to have a less restrictive environment in which to innovate. The consensus view is rendered viable in a partnering culture undoing many barriers and restructuring many concepts. The paper postulates that software development is a paradigm and shifts through the forming, proliferating, norming and performing stages. This postulate is substantiated by citing evidence for the following associations:The forming stage is associated with the development of early computer programs.The proliferating stage is associated with closed architecture.The norming stage is associated with open architecture to create interoperability.The performing stage is associated with open source to freely share and improve source codes.

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McCulloh, K. A., and J. S. Sperry. "Patterns in hydraulic architecture and their implications for transport efficiency." Tree Physiology 25, no. 3 (March 1, 2005): 257–67. http://dx.doi.org/10.1093/treephys/25.3.257.

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Journal articles on the topic 'Hydraulic architecture'

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