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Auswahl der wissenschaftlichen Literatur zum Thema „KHM cable model“
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Zeitschriftenartikel zum Thema "KHM cable model"
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He, Guo Jing, Zhong Quan Zou, Yi Qing Ni und Jin Ming Ko. „Seismic Response Analysis of Multi-Span Cable-Stayed Bridge“. Key Engineering Materials 400-402 (Oktober 2008): 737–42. http://dx.doi.org/10.4028/www.scientific.net/kem.400-402.737.
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Based on the dynamic characteristics analysis results of a precise three-dimensional finite element model, the earthquake responses of the bridge are analyzed in this paper. The influences of cable local modes and stabilizing cables on the seismic response are investigated by using different mode combinations and different models. It is found that the influence of cable local modes is negligible on the side towers while significant and not negligible on the main tower; the influence of the stabilizing cables is significant and not negligible on side towers, while minor and negligible on the main tower. As for the deck displacements, the influence of cable local modes is minor and negligible, while that of longitudinal stabilizing cables is significant and not negligible.
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Pérez-Aracil, J., A. M. Hernandez-Díaz, J. F. Jiménez-Alonso und F. J. Puerta-Lopez. „Fatigue Assessment of a Slender Footbridge Based on an Updated Finite Element Model“. Key Engineering Materials 774 (August 2018): 589–94. http://dx.doi.org/10.4028/www.scientific.net/kem.774.589.
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Finite element model updating is a well-known technique to better characterize the real behaviour of civil engineering structures. The updated numerical model can be used to perform a more accurate structural assessment. Herein, its effectiveness is validated through the fatigue assessment of a lively footbridge considering two different numerical models: (i) a preliminary finite element (FE) model and (ii) an updated version of the preliminary model based on the modal parameters of the footbridge identified experimentally. For this purpose, the Malecon footbridge (Murcia, Spain) has been considered. This footbridge, a cable-stayed structure, is prone to vibrate in vertical direction under continuous walking pedestrian flows so fatigue damage might be expected on its supporting cables. A detailed FE model of the footbridge has been performed and subsequently updated based on the experimental modal parameters of the structure. The behaviour of the pedestrian flows was characterized by field observations. Finally, a comparison is performed between the fatigue damage of some cables of the footbridge considering the two mentioned FE models. The safe life method was used to assess such damage. As result, a maximum relative difference around 52 % was obtained between the two numerical models.
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Li, Yan, Da Gang Lv und Hong Fei Sheng. „Fatigue Reliability Analysis of the Stay Cables of Cable-Stayed Bridge under Combined Loads of Stochastic Traffic and Wind“. Key Engineering Materials 456 (Dezember 2010): 23–35. http://dx.doi.org/10.4028/www.scientific.net/kem.456.23.
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The existent studies on cable stays fatigue for the serviced cable-stayed bridge generally only considered traffic or wind load action respectively. The long span cable-stayed bridges are very sensitive to wind load, so the fatigue estimation of cable stays considering traffic and wind load simultaneously is very important for the bridge safety. In the present research, taking an actual bridge as an example, based on linear cumulative damage theory, fatigue reliability of cable stays is analyzed under combined load of vehicles and wind. Firstly, based on the long-term traffic survey and wind speed data, traffic and wind load probability distribution models for the bridge are built respectively. Secondly, an intensive computational work is performed to obtain stress time history of the stay cables in the typical time block by running self-compiled Bridge-Vehicle-Wind interaction dynamic response analysis program. Thirdly, the stress result is updated in accordance with traffic growth and extreme wind speed changing in service period. The stress amplitude and frequency are attained by rain-flow cycle counting method. Finally, the fatigue damage limit state function of cable stays is proposed based on linear cumulative damage theory, and solved by Monte-Carlo method. The analysis result shows that the effect of buffeting wind load on the fatigue reliability of cable stays is significant, the influence degree increases generally in accordance with the order from short cable to long cable. The fatigue life of cable under designed safety probability reduces by the range from 2% to 63%, average 50% compared to only considering traffic load. So fatigue assessment of stay cables should take traffic and wind loads together into account. The proposed analysis framework offers a referenced fatigue assessment approach for conventional long span bridges.
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Votsis, R. A., M. M. Abdel Wahab und M. K. Chryssanthopoulos. „Simulation of Damage Scenarios in an FRP Composite Suspension Footbridge“. Key Engineering Materials 293-294 (September 2005): 599–606. http://dx.doi.org/10.4028/www.scientific.net/kem.293-294.599.
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Simulations of damage scenarios were carried out using a finite element model of a newly constructed FRP composite footbridge, the Wilcott footbridge. This footbridge represents a new generation of suspension footbridges that have lightweight decks made of pultruded glass fibre reinforced polymer (GFRP) composite elements. It offers several advantages over conventional steel or concrete footbridges, e.g. speed of installation, high resistance to corrosion and saving in weight and foundations. On the other hand, its lightness and slenderness make it more sensitive to dynamic effects, both at serviceability and ultimate limit states. A finite element model using 3-D beam elements was constructed and damage scenarios were simulated and introduced in the model. The natural frequencies, mode shapes as well as time responses due to pedestrian loading were predicted. Different size of delamination in the composite deck was simulated at various locations along the bridge. The sensitivity of natural frequencies and mode shapes due to delamination were assessed by comparing the results of the damaged deck to those of the reference intact deck. The effect of changes in the cables’ initial strains on the modal parameters was also examined, and the sensitivity of modal parameters to cable degradation was assessed.
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Bi, Hong Tao, und Yan Li. „The Length Optimization of Non-Stayed Cable Segment to Low-Pylon Cable-Stayed Bridge“. Key Engineering Materials 540 (Januar 2013): 131–39. http://dx.doi.org/10.4028/www.scientific.net/kem.540.131.
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An optimization model was proposed in order to investigate the effect of the non-stayed cable segment length on the performance of a low-pylon cable-stayed bridge. Based on the structural analysis of the cable-stayed bridges, the proposed model aims to adjust the structural internal force by changing the non-stayed cable segment length. The most reasonable length of non-stayed cable segment was obtained by the optimization analysis.
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Sun, Yong Ming, und Hang Sun. „Impact Analysis of the Flexural Rigidity on the Frequency and Tension of the Stay Cable“. Key Engineering Materials 540 (Januar 2013): 153–63. http://dx.doi.org/10.4028/www.scientific.net/kem.540.153.
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Research and practice show that frequency method is still the most practical and accurate method among all kinds of cable force measurements. Based on the classical string vibration theory, the finite element model of stay cable was created, and a method of iteratively computing stay cable balance curve considering with flexural rigidity was proposed. How dose the flexural rigidity affects the balance curve of stay cable was discussed, and the changing curves of the distance-to-sagging ratio following the pull-to-bend ratio were plotted, which indicated the bigger flexural rigidity, the smaller sagging. 25 pairs cable modality of Xichang cable stayed bridge were accurately analyzed, mode crossover was testified by finite element method, changing curves of frequency and mode shape following the cable force were separately plotted, and changing rule was induced, practical cable force computing method was given. Frequency difference is suitable to judge the rank of actual measurement frequency, and the second frequency is recommended to compute cable force. Engineering instance analysis testified, the method of practical cable force measurement could rule out errors by mode crossover, and be applied to cable with any lengths and any force.
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Zhou, Jia Fu, und Jie Sheng Wu. „The Simulation and Fatigue Life Prediction of a Cable Harness in an Industrial Robot“. Key Engineering Materials 464 (Januar 2011): 293–98. http://dx.doi.org/10.4028/www.scientific.net/kem.464.293.
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This paper presents a method to simulate the behavior of the cable harness using the absolute nodal coordinat formulation (ANCF) and to predict the fatigue life while computing the strain time history of the point of interest. Rigid body dynamics is applied for the robot system, while ANCF is used for the cable harness. The simulation is performed by using the dynamic analysis process. The material property of the cable is obtained by a test. A simplified model is prepared. With these data, the behavior of the cable is simulated and the fatigue life is predicted.
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Hui, Liu. „Dynamic Characteristics of a Long-Span Cable-Stayed Bridge“. Key Engineering Materials 480-481 (Juni 2011): 1496–501. http://dx.doi.org/10.4028/www.scientific.net/kem.480-481.1496.
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In order to study the dynamic characteristics of a super-long-span cable-stayed bridge which is semi-floating system, the spatial finite element model of this cable-stayed bridge was established in ANSYS based on the finite element theory.Modal solution was conducted using subspace iteration method, and natural frequencies and vibration modes were obtained.The dynamic characteristics of this super-long-span cable-stayed bridge were then analyzed.Results showed that the super-long-span cable-stayed bridge of semi-floating system has long basic cycle, low natural frequencies, dense modes and intercoupling vibration modes.
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Rudolf, Robert T., Florian Roscheck, Yuuta Aono und Torsten Faber. „Mass-Optimized Design of Guyed Wind Turbine Tower Using Struts“. Key Engineering Materials 577-578 (September 2013): 277–80. http://dx.doi.org/10.4028/www.scientific.net/kem.577-578.277.
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Continuing upscaling trends in turbine height, rotor diameter, and rated power have resulted in massive, expensive tower structures. A modified guyed tower concept with struts (GTS) is proposed for saving material, and the basic design is made for a 2.5MW turbine. The tower and cable dimensions are optimized for lowest system cost given yield constraints. DACE (design and analysis of computer experiments) methods of sampling and surrogate model optimization are used for efficient parameter study and optimization of the ABAQUS finite element model using DAKOTA software. The resulting design is highly effective in transferring turbine loads from the tower to the cables. A mass savings of 41% is calculated vs. conventional structures, and further investigation of the GTS is recommended for both onshore and offshore applications. Additionally, the concept of retowering older turbines is introduced and proposed as an economic alternative to the common practice of repowering old wind farms with larger, new machines. The GTS is specifically suited to this application. Lastly, the design methodology developed for this study is shown to be effective and efficient; it can be applied for the massoptimization of similar cablesupported truss structures.
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Zheng, G., Yi Qing Ni, J. M. Ko und X. Xu. „Tension-Dependent Internal Damping of a Cable Model“. Key Engineering Materials 243-244 (Juli 2003): 415–20. http://dx.doi.org/10.4028/www.scientific.net/kem.243-244.415.
Der volle Inhalt der QuelleDissertationen zum Thema "KHM cable model"
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Rada, Dominik. „Přenosová technologie G.mgfast“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442370.
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The master thesis deals with G.fast and G.mgfast transmission technologies, including their parameters. The work deals with the principle of vector DMT modulation and the possibility of time duplex TDD and full-duplex FDX in two-way communication used in these technologies. The following is a description of the line using the KHM model, which is suitable for simulations in the transmission band using G.fast and G.mgfast technologies. Subsequently, the disturbing effects of crosstalk at the near end of NEXT and the far end of FEXT and their elimination with these technologies are discussing. Part of the work explains supporting calculations to determine the SNR and bit allocation to calculate the baud rate. The work describes the methods of compensation of crosstalk FEXT and NEXT, which affect the resulting baud rate. The work also includes an application for simulation of transmission speed as a function of distance for G.fast and G.mgfast technologies, allowing changing input parameters and adjusting the transmission bandwidth based on G.9700 and G.9701 standards. Also, in work, an application is created to display the compensation of the influence of the transmitted signal crosstalk FEXT and NEXT, which allow the import of measured crosstalk between individual participants. The issue of influencing crosstalk for accurate measurements in the laboratory is also discussing. An application in the MATLAB environment is creating to display the measured characteristics.
Konferenzberichte zum Thema "KHM cable model"
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Acatauassu, Diogo, Stefan Host, Chenguang Lu, Miguel Berg, Joao Costa, Aldebaro Klautau, Per Odling und Per Ola Borjersson. „KHM cable model parameters for ITU-T G.fast reference loops“. In 2015 IEEE Conference on Standards for Communications and Networking (CSCN). IEEE, 2015. http://dx.doi.org/10.1109/cscn.2015.7390439.
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Ravet, Fabien, Atle Børnes, Carlos Borda, Even Tjåland, Halfdan Hilde und Marc Niklès. „DEH Cable System Preventive Protection With Distributed Temperature and Strain Sensors“. In 2012 9th International Pipeline Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/ipc2012-90274.
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Hydrate and wax formation in subsea flowlines is a major cause of production impairment. Among various approaches used to minimize the risk, Direct Electrical Heating (DEH) is being applied. DEH is based on passing a current through the pipe wall to mitigate heat losses from the fluid to the surroundings during events which require flow assurance measures. The Piggyback Cable, a high voltage cable attached to the DEH pipeline, is during operation exposed to thermal and mechanical loads which may be critical for the integrity of the DEH system. The overall safety requirement is that any potential Piggyback Cable fault is detected and disconnected from the power source before damage is caused to the pipeline. Conventional cable fault detection methods based on current measurements give adequate protection for the main part of the pipeline. However, for the far end of the Piggyback Cable complementary fault detection is required. A method based on fiber break monitoring has been qualified for this purpose. The new method is implemented in the North Sea on two DEH pipelines operated by Statoil, 43 and 21 km long respectively. The protection is facilitated by standard single-mode fibers integrated into the DEH cables. Although not basis for the design the integrated fibers open up possibilities for temperature and strain sensing using stimulated Brillouin scattering. Sensing has been performed on a 43 km DEH pipeline using the DITEST AIM (Distributed Temperature and Strain Asset Integrity Monitoring). Analysis of the sensing results reveal that distributed fiber optic sensing is capable of pin-pointing thermal events and strain induced loads for an object of this length.
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Litman, R. B., H. A. Scarton, K. R. Wilt und G. J. Saulnier. „‘Acoustic Fiber’ Aluminum-Clad Copper Cable for Communication and Power Transmission“. In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-52819.
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An ‘acoustic fiber’, analogous to optical fiber, is presented as a means of long-distance data and energy transfer. Low-loss axial guided waves are produced along a cable-like waveguide, which is composed of a solid core and a cladding layer, where the cladding’s acoustic speeds of sound, both longitudinal and transverse, exceed those of the core. A similar condition exists in glass fiber optic cables consisting of a core surrounded by a cladding of lower index of refraction. This results in total internal reflection of light at the core-cladding interface and effective confinement of light to the core. A specific acoustic waveguide construction is analyzed, composed of an aluminum cladding with longitudinal wave speed of 6.198 km/s and shear wave of 3.122 km/s and copper core with longitudinal speed of 4.505 km/s, and shear speed of 2.164 km/s. Finite element simulations show that a guided wave mode that is confined largely to the core exists and is capable of propagating long distances with very little loss to the surroundings. A 6 mm diameter aluminum-cladded copper core (2 mm diameter) fiber was found to have a propagation loss of 0.023 dB/m when operating at 2 MHz predict (neglecting material attenuation). When including material attenuation, the same waveguide produced a propagation loss of 0.24 dB/m. Similarly, a 12 mm cladding with 4.8 mm core at 1 MHz had losses of 0.10 dB/m, and a 22 mm diameter cladding with 9 mm core at 500 kHz had losses of 0.062 dB/m. Relationships were found between frequency, total diameter and core diameter yielding the highest efficiencies. The minimum total dimension of an aluminum-clad-copper acoustic fiber was found to have an inverse relationship with frequency. The optimum ratio of core to total diameter was about 0.45 but between values of 0.35 and 0.5, attenuation was relatively constant (insensitive to frequency). Outside of that range, attenuation climbed rapidly. Due to this property, attenuation in properly designed fibers should always be dominated by, and roughly equivalent to, the material attenuation rather than attenuation due to leakage.
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Grindheim, Jan Vidar, Ken E. Welker und Inge Revhaug. „Application for Improved Awareness of Cable Geometry During Seismic Survey Operation“. In ASME 2019 38th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/omae2019-95038.
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Abstract Seismic surveys for petroleum exploration employ a number of towed cable streamers of lengths in the order of 3∼12 km. Accurate positioning is important both for navigation and control of the streamer spread and for seismic data processing. In the present study, a numerical streamer model based on a Finite Element Method is implemented both as an Extended Kalman filter and an Ensemble Kalman filter. The streamer model includes features such as tailbuoy, locally estimated sea current introduced at each node, control bird inputs, cable stretch and tension. The filter implementations are intended to blend the streamer model with observations such as acoustic range measurements and satellite navigation positioning. The implementations have been compared and validated employing full scale data for two line changes. The purpose is to investigate the filters’ performance during periods with poor or missing observations.
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Grosenbaugh, Mark A., Louis L. Whitcomb, Brian Bingham, Jason I. Gobat und Chris Young. „Numerical Simulation of the Deployment of a Hybrid ROV Optical Fiber Tether“. In ASME 2007 26th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2007. http://dx.doi.org/10.1115/omae2007-29442.
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This paper describes a numerical code for simulating the dynamics of an unmanned, underwater vehicle system that is self-propelled and tethered to a surface ship through an optical fiber tether. The vehicle, called a hybrid ROV, uses a buffered, single-mode optical fiber with a maximum working load of 1.7 N for communication and data transmission. The vehicle is designed to go to the deepest parts of the ocean and for exploring beneath the Arctic ice cap. The optical fiber tether is stored in a pair of canisters, one mounted on the vehicle and one mounted on a garage that is lowered from the ship. The canisters each hold 20 km of fiber, which is pulled out during operations when the tension at the canister reaches a threshold value, which is set to the maximum working load of the fiber. The numerical simulation is based on the two-dimensional version of WHOI Cable, a finite-difference solver of the cable equations that includes bending stiffness to model low-tension effects. A velocity/tension based payout algorithm was incorporated into the code to model the behavior of the canisters. In the payout model, the payout velocity is set equal to zero below the threshold tension and varies linearly with tension above the threshold value up to a maximum pay out velocity. Hydrodynamic drag models for axial and normal fluid loading, whose values are a function of Reynolds number, are used to calculate local drag coefficients of the optical fiber. Examples of the vehicle being lowered to the sea bottom in uniform and shear currents are used to demonstrate the capabilities of the code and the performance of the tether and payout system.
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Maandal, Gerard Lorenz D., Mili-Ann M. Tamayao und Louis Angelo M. Danao. „An Analysis of the Technical Feasibility of Off-Shore Wind Energy in the Philippines“. In ASME 2019 13th International Conference on Energy Sustainability collocated with the ASME 2019 Heat Transfer Summer Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/es2019-3835.
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Abstract The technical feasibility of off-shore wind energy in the Philippines is assessed. Geographic information system is utilized to integrate the different technical data into a single model. Off-shore wind speed data for five years at elevations 10m, 20m, 80m, and 100m from a local database was used as reference for the wind resource study. Two wind turbines were considered for the energy conversion component, Siemens SWT-3.6-120 and Senvion 6.2 M126. The wind speed data was interpolated to 90m and 95m using standard power law to match the hub heights of the turbines studied. The wind power density, wind power, and annual energy production were calculated from the interpolated wind speeds. Areas in the Philippines with capacity factor greater than 30% and performance greater than 10% were considered technically viable. Exclusion criteria were applied to narrow down the potential siting for offshore wind farms, namely, active submerged cables, local ferry routes, marine protected areas, reefs, oil and gas extraction areas, bathymetry, distance to grid, typhoons, and earthquakes. Several sites were determined to be viable with north of Cagayan having the highest capacity factor. The highest wind capacity factor for the offshore wind farms are located in north of Ilocos Norte (SWT-3.6-120: 54.48%–62.60%; 6.2M126: 54.04%–64.79%), north of Occidental Mindoro (SWT-3.6-120: 46.81%–60.92%; 6.2M126: 45.30%–62.60%) and southeast of Oriental Mindoro (SWT-3.6-120: 45.60%–59.52%; 6.2M126: 45.30%–62.60%). However, these sites are not acceptable due to technical, social, and political constraints. The constraints considered in the study are active submerged cables with a buffer of 5 km, local ferry routes with a buffer of 3km, marine protected areas with a buffer 3 km, reefs with a buffer of 3 km, oil and gas extraction areas with a buffer of 5 km, bathymetry less than 50m, distance to grid of within 120 km, historical typhoon tracks with greater than 250 kph and 50 km buffer, and historical earthquakes with greater than 6.5 magnitude with a buffer of 15 km. Upon application of these exclusion criteria, the potential sites for offshore wind farms are north of Cagayan, west of Rizal, north of Camarines Sur, north of Samar, southwest of Masbate, Dinagat Island, Guimaras, and northeast of Palawan.
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Shaffer, Phillip L. „Distributed Control System for Turbine Engines“. In ASME 1998 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/98-gt-016.
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A Distributed Control System (DCS) for a turbine engine has been demonstrated and tested, consisting of prototype Electronic Interface Units (EIUs) connected to data and power busses. In the DCS, a central control computer communicated with smart sensors and smart actuators via a 2.5 megabit/sec digital data bus, using the Fieldbus protocol. Power was distributed to the smart devices as 100-kHz 100V peak AC, allowing light, simple power converters at each smart device. All smart sensors, smart actuators and cables were dual-redundant. The smart actuators received position demand from the central control computer, exchanged data between channels to provide local redundancy management, closed the position loop locally, and reported actuator position to the central controller. Smart sensors converted sensed signals to digital values in engineering units, and performed local built-in tests. Testing of the DCS was done in a closed-loop simulation with an engine model. Frequency response of the DCS was almost identical with the conventional system.
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Hamilton, J. A., J. C. C. Henriques, F. Cazenave, P. McGill, W. Radochonski, A. F. O. Falcão, L. M. C. Gato und R. P. F. Gomes. „Results From Numerical Simulation and Field Tests of an Oceanographic Buoy Powered by Sea Waves“. In ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-24132.
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The paper presents a performance analysis of a wave-energy converter designed for oceanographic applications to generate 300–500 W of electrical power on average. The prototype consists of a small draft cylindrical buoy connected to a submerged anti-heave plate by a hydraulic power takeoff system and cable. Engineering details and design of the system are based on the results of a detailed time-domain hydrodynamic analysis of the system, discussed here. The performance of the prototype is assessed with respect to the submerged plate size/added-mass and the effectiveness of latching schemes. Additionally, results for the power extraction are statistically compared with measurements performed during field tests in Monterey Bay, California. During these tests performance measurements were logged by the buoy, and wave data was recorded by a measurement buoy positioned 1 km from the deployment site. This allows the comparison of actual performance to model predictions run for the sea state present during testing. In general, the results of the numerical model match fairly well with the data acquired in field testing. The proposed causal latching control schemes have been shown to be ineffective for this type of wave-energy converter.
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Williamsen, Joel, Michael Squire und Steven Evans. „Predicting orbital debris-induced failure risk of wire harnesses using SPH hydrocode modeling“. In 2019 15th Hypervelocity Impact Symposium. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/hvis2019-029.
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Abstract This paper describes a method derived to assess the probability of two types of complex cable failures (partial and full wire breaks), considering their location with respect to the debris spray from penetration of multi-layer insulation (MLI) suspended over them, and the likelihood of impacting particle sizes and velocities as predicted by NASA’s model for predicting orbital debris impact size and velocity distributions for satellites in low earth orbit, ORDEM. The smooth particle hydrodynamics (SPH) code was used to determine the onset of these two failure types following hypervelocity impact for different orbital debris velocities, sizes and orientations relative to four different wire locations for a prototypical satellite in a 98-degree polar orbit at an altitude of approximately 750 km (i.e., a typical weather satellite). Interpolations between hydrocode results, combined with ORDEM predictions of orbital debris likelihoods, were used to predict overall risk of each failure type. Adding a few layers of beta cloth over the wires cut the risk of each failure type in half.
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„Novel Outside-Facility Renovation Technology to Improve Cost-Effectiveness by Long-Term Safe Use“. In Structural Health Monitoring. Materials Research Forum LLC, 2021. http://dx.doi.org/10.21741/9781644901311-40.
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Abstract. In order to provide telecommunication and FTTH services, we, NTT, have installed a large number of facilities such as utility poles and optical cables. The number of poles is about 11.9 million and the total length of all installed cables is now about 2.3 million km. These facilities are inspected and maintained by visual inspection by workers every 5 to 10 years, which imposes great costs on the operator. Therefore, we are researching a novel outside-facility renovation technology that can improve cost-effectiveness by long-term safe use. This technology consists of two techniques: a visualization technique of unbalanced tension and a quantitative analysis technique to determine the relationship between unbalanced tension and structural deterioration. In this paper, we describe the concept of the proposed technology. When a utility pole is newly installed, its design assumes that the maximum load consists of wind pressure on the cables. However, when it is impossible to construct a guy wire for bearing the load applied to the utility pole, an unbalanced load occurs because the load cannot be balanced. In addition, when the number of users of various services increases and cables are newly laid, unbalanced loads are generated. Utility poles carrying these unbalanced loads are at significant risk of collapse due to the presence of deflection, inclination, and cracks. Our proposal focuses on the unbalanced load itself, and by detecting and countering it, we aim to enable the use of outside-facilities for a longer period than at present and to reduce replacement costs without sacrificing safety and security. In addition, we also describe how ensuring the long-term safe use of outside-facilities can improve cost-effectiveness. The proposed technique first acquires 3D point cloud data by using 3D laser scanner. It then creates a 3D facility model and calculates the tension in utility poles and cables. In addition, we introduce a novel method to estimate the loads and tension of a whole span from part of the span. Experiments are conducted to compare the estimated and measured values. The results confirm the good agreement of the values (within 10%) which validates the proposal. We aim to realize a tension visualization scheme with improved accuracy.