This master’s thesis deals with design of a hydraulics bending machine. Bending machine will be used primarily for bending reinforcement bars in the shape of stapes. It consists of bending, sliding and chute system, which are located in the machine frame. Drive of each system is provided by a rotary and two linear hydraulic motors. Then there is described a hydraulic system and selection of its most important parts. Work is supplemented by visual documentation in the form of images of individual systems were processed in a CAD system Inventor 2010

The aim of this thesis is to analyze the possibility of mechanical design platform lifts. Proposal lifting platform with mechanical and hydraulic drive with a capacity of 3500 kg and lift 600 mm. The work is mainly focused on design and strength calculation mechanism and structure. Proposal hydraulic circuits and the development drawings for both types of drive.

This diploma´s thesis aims to model the hydraulic model of the Brno – Ivanovice water supply system. The software MIKE URBAN for model hydraulic model of water supply system was used. It was performed a simulation of the various states of loading. The water supply system was assessment of pressure ratios. The outcome of this work is calibrated hydraulic model of water supply system. The appendix consists also of drawings, which represented pressure ratios, which are situated on water supply system. On the fourth drawing is described transparent situation of Brno-Ivanovice water supply system.

Energy and the natural environment are central concerns among stakeholders across the globe. Decisions on this scale often require interaction among a myriad of institutions and individuals who navigate a complex variety of challenges. In Denton, Texas in 2014, voters were asked to make such a decision when tasked with a referendum to determine whether the city would continue to allow hydraulic fracturing activity within its borders. For social scientists, this situation requires further analysis in an effort to better understand how and why individuals make the decisions they do. One possible approach for exploring this process is a method of poststructuralist critical rhetorical analysis, which is concerned with how individuals’ identities change through interaction with institutions. This study reflects upon the texts themselves through a poststructuralist critical rhetorical analysis of images employed by those in favor of and those against Denton’s ban on hydraulic fracturing in an attempt to identify images that alter the grid of intelligibility for the audience. The paper includes deliberation about the relative merits, subsequent disadvantages, and possible questions for further study as they relate to the theoretical implications of critical rhetorical analysis as information science. Ultimately, the study identifies poststructuralist critical rhetorical analysis as a method for solving information science problems in a way that considers closely the way identity is shaped through engagement with institutions.

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Rhododendron is a monophyletic group that inhabits many different climates. One clearly defined diversification was from temperate ancestors into tropical habitats. The focus of this work was to explore leaf and stem anatomical traits in relation to habitat (temperate and tropical) and elevation of the native range. A closely-related group of Rhododendron was selected to reduce variation in genetic history and reveal environment–associated adaptive traits. Vessel anatomical traits of Rhododendron accessions were assayed for the trade of between safety (protection against catastrophic failure) and efficiency (high theoretical conductivity). Rhododendron wood and vessels were found to be relatively safe. The metrics of wood efficiency were higher for the tropical species. Thus, a trade-off between safety and efficiency was found although the wood of Rhododendron is characterized as highly safe. Leaf anatomical traits of Rhododendron were assayed for habitat and elevation. Leaves on tropical species were thicker and denser compared with temperate species. Idioblasts were always found in tropical leaves but not in temperate species. Leaves of tropical species were more xeromorphic (drought tolerant) than those of temperate species. Increasing elevation of the native range did not influence leaf anatomical traits. Idioblast abundance and leaf water relations traits were assayed for tropical Rhododendron species. Idioblast expression varied from 5% to 28% and stomatal pore index varied from 0.08 to 3.3. Idioblast expression was highly correlated with leaf succulence, and water deficit at the turgor loss point. Idioblast expression was positively associated with leaf capacitance for thin (< 0.5 mm) leaves. Thus, idioblasts can serve as a water buffer for relatively thin leaves. Synthesis–Wood traits of evergreen Rhododendron shrubs reflect adaptation for safety. Although tropical species have significantly higher efficiency, wood safety is still the dominant feature. The implication of high wood safety is constrained water flow and a potential for low water potential. Both leaf succulence and the presence of idioblasts in thin leaves enhances leaf capacitance and provides some buffering against short-term drought. These leaf adaptations in tropical Rhododendron shrubs likely reflect the abundance of epiphytes in this group. / Ph. D. / <i>Rhododendron</i> is a very diverse genus that is found in many different habitats from arctic to tropical. However, most of the species are evergreen with a slow growth rate. The goal of this study was to explore the variation in wood and leaf anatomical traits in order to explain how these plants can succeed in so many different habitats. The vessels in wood of temperate species were found to be very small. Although the size of the vessels increased for tropical species, they were still small relative to many other species. Surprisingly, leaf traits suggested greater drought tolerance for tropical species compared with temperate species. A unique anatomical trait called idioblasts was found only in leaves of tropical species. Idioblasts were very large cells, found just below the upper epidermis, which occupied up to 30% of the leaf volume. Idioblasts were found to help buffer water loss for thin tropical leaves. In summary, <i>Rhododendron</i> wood constrains water flow for plants in all habitats, which will induce water stress in warm or dry areas. Consequently, leaves have drought tolerance traits in tropical regions. Therefore, anatomical traits of wood and leaf help explain how <i>Rhododendron</i> species can occupy a wide diversity of habitats.

This Diploma thesis occupies with design of hydraulic puller. In work are mentioned possible types of construction. Choice construction of puller is disposed with parameters: maximum pushing force 50 kN, speed of piston rod 0,05 m/s. This work also contains FEM analysis by computer programme I-DEAS. The work also occupies with design of fluid drive.

<p>The electrification trend affecting off-road vehicles is paving the way toward dedicated electrified hydraulic actuation systems. Although traditional centralized fluid power architectures are still utilized in many applications for low cost, power density, and reliability, nowadays emission policy results in an increasing interest in developing electro-hydraulic actuator (EHA) solutions. EHAs enable non-throttling actuation and energy recuperation during overrunning loads, leading to higher transmission efficiency and lower fuel consumption. These features in energy efficiency make EHAs competitive in meeting emission regulations compared to conventional hydraulic solutions.</p> <p>The key challenge in developing the EHA solution comes from the high cost and space requirements, especially for the adoption of self-contained EHAs in mobile applications. In this study, two architectures for the EHA are proposed, a closed-circuit architecture and an open-circuit one, to determine the most practical and efficient configuration. The most effective open-circuit architecture with distributed concepts is further investigated for implementation, which requires less modification of the mechanical structures and performs more efficiently than the closed-circuit alternative. The proposed EHA is driven by an electro-hydraulic unit (EHU) consisting of a variable-speed electric motor and a fixed-displacement hydraulic pump, which is relatively cost-effective. A novel hydraulic configuration is proposed, which allows the EHA to cover full-speed operating ranges in four quadrants. </p> <p>To verify the EHA design, the behavior of the proposed system should be predicted prior to costly experiments and demonstrations. For this purpose, an integrated simulation model is developed based on the lumped parameter approach in the Amesim environment. The model includes the electric system, the hydraulic system, and the mechanism to be implemented, which are capable of flexible analysis of functionality, efficiency, and thermal performance.</p> <p>In this work, a dedicated test rig for EHA testing is developed. The test rig can help verify EHA performance, test the control algorithm, and diagnose errors before implementing the system on real applications. The experimental results from the test rig also validate the simulation model. An independent load drive of the test rig allows testing all possible  loading conditions of the proposed EHA, thus demonstrating the energy performance in four quadrants. Thermal behavior is investigated with long duty cycles to determine the need for additional cooling equipment. After the validation of the hydraulic configuration, a power electronics setup is added to the test rig, which allows to drive the EHA system with the novel designed EHUs. Validation on the test platform paves the way for implementation in a vehicle. </p> <p>As a final step, the proposed EHA system is implemented in a reference vehicle, a Case New Holland TV380 skid steer loader. A novel designed EHU is adopted to drive the system for technology demonstration. The energy savings capacity of the EHA is investigated in comparison to the baseline measurements of the traditional open-center hydraulic architecture. The impressive savings from the reduction of throttling losses and energy recovery guide the possible commercialization of such EHAs in mobile hydraulic applications. The controller design of the implemented EHA system is investigated with the aim of improving the dynamic performance, e.g., reducing damping oscillation. Basic power management strategies are also studied to integrate EHA with the power train of current hydraulic machines. Regarding future work, based on this research but not within the scope of this study, the proposed EHA system can be adopted with different types of prime movers, such as axial piston machines as the hydraulic part of an EHU. Furthermore, the design approach proposed in this study can help resize the EHA system for other applications with different loading conditions and power requirements, and the energy savings capability can be further investigated. With this, a comprehensive market analysis will be performed for the commercialization of EHA. </p>

Between 1961 and 1976 Häi Hung province -- present day Häi Duong and Hung Yên -- lost the equivalent of two entire districts of agricultural land. How could so much land be abandoned under a collectivised agriculture system? And what role did poor water control infrastructure play in creating such a situation?¶ I answer these questions by examining the historical patterns of hydraulic development in northern Vietnam from the beginning of the 19th century until the introduction of the Production Contract system in 1981. Underlying both the French colonial and communist visions of modernity and economic development was a belief that improving agricultural productivity, of which large-scale hydraulic infrastructure was an important component, could catalyse growth in the rural economy, which could then finance industrialisation. I argue throughout this thesis that developing large-scale hydraulic infrastructure in the Red River delta has relied upon the creation of a hydraulic bargain between the state and water users. This is in contrast to Wittfogel's theory of the hydraulic state, insofar as developing hydraulic infrastructure has depended upon the active political and economic participation and support of water users, and not the absolute power of the state. The political economic history of the hydraulic bargain highlights the relative power of peasants to influence the direction of large-scale hydraulic development and, as such, the shape of the Red River delta's wet-rice economy.