The Experts below are selected from a list of 276690 Experts worldwide ranked by ideXlab platform
Takeshi Ohkuma - One of the best experts on this subject based on the ideXlab platform.
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Full-Scale Measurement of wind-induced internal pressures in a high-rise building
Journal of Wind Engineering and Industrial Aerodynamics, 1997Co-Authors: N. Kato, Y. Niihori, T. Kurita, Takeshi OhkumaAbstract:Abstract The characteristics of wind-induced internal pressures in a high-rise building have been investigated. Full-Scale Measurement were taken using absolute pressure meters, which allowed high-resolution Measurements. This paper outlines full-Scale Measurements of wind velocity, wind direction and external and internal pressures on a 29-story building, commencing in January 1993. It also describes the characteristics of natural wind above the building's penthouse and mean wind-induced internal pressures measured in September 1995 when a typhoon hit the Kanto area. The internal pressure coefficients obtained from these Measurements were about −0.26, and were constant over the building's height. The influence of internal walls and doors on measured mean internal pressure coefficients was found to be insignificant, and roughly the same values were obtained at different locations on the same floor. The mean internal pressure coefficients estimated from the mean wind pressure coefficient obtained from wind tunnel testing was — −0.26, which is the same as that obtained from the full-Scale Measurement. Therefore, it is inferred that the mean wind pressure coefficient obtained from the wind tunnel testing is sufficient for examining average internal pressure.
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Full-Scale Measurement of wind pressures and response accelerations of a high-rise building
Journal of Wind Engineering and Industrial Aerodynamics, 1991Co-Authors: Takeshi Ohkuma, Y. Niihori, Hisao Marukawa, N. KatoAbstract:Abstract This paper describes the results of full-Scale Measurements of wind pressure and wind-induced response acceleration for an 18 storey building 68 m high. It also gives estimates of the response acceleration of this building in accordance with the AIJ Standard for Loads and External Forces on Buildings and Structures, the National Building Code of Canada, and the method suggested by Ohkuma and co-workers. The values of estimated response acceleration correspond to the values of the full-Scale Measurements.
N. Kato - One of the best experts on this subject based on the ideXlab platform.
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Full-Scale Measurement of wind-induced internal pressures in a high-rise building
Journal of Wind Engineering and Industrial Aerodynamics, 1997Co-Authors: N. Kato, Y. Niihori, T. Kurita, Takeshi OhkumaAbstract:Abstract The characteristics of wind-induced internal pressures in a high-rise building have been investigated. Full-Scale Measurement were taken using absolute pressure meters, which allowed high-resolution Measurements. This paper outlines full-Scale Measurements of wind velocity, wind direction and external and internal pressures on a 29-story building, commencing in January 1993. It also describes the characteristics of natural wind above the building's penthouse and mean wind-induced internal pressures measured in September 1995 when a typhoon hit the Kanto area. The internal pressure coefficients obtained from these Measurements were about −0.26, and were constant over the building's height. The influence of internal walls and doors on measured mean internal pressure coefficients was found to be insignificant, and roughly the same values were obtained at different locations on the same floor. The mean internal pressure coefficients estimated from the mean wind pressure coefficient obtained from wind tunnel testing was — −0.26, which is the same as that obtained from the full-Scale Measurement. Therefore, it is inferred that the mean wind pressure coefficient obtained from the wind tunnel testing is sufficient for examining average internal pressure.
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Full-Scale Measurement of wind pressures and response accelerations of a high-rise building
Journal of Wind Engineering and Industrial Aerodynamics, 1991Co-Authors: Takeshi Ohkuma, Y. Niihori, Hisao Marukawa, N. KatoAbstract:Abstract This paper describes the results of full-Scale Measurements of wind pressure and wind-induced response acceleration for an 18 storey building 68 m high. It also gives estimates of the response acceleration of this building in accordance with the AIJ Standard for Loads and External Forces on Buildings and Structures, the National Building Code of Canada, and the method suggested by Ohkuma and co-workers. The values of estimated response acceleration correspond to the values of the full-Scale Measurements.
Niklas Carlsson - One of the best experts on this subject based on the ideXlab platform.
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power law revisited large Scale Measurement study of p2p content popularity
International Workshop on Peer-to-Peer Systems, 2010Co-Authors: Gyorgy Dan, Niklas CarlssonAbstract:The popularity of contents on the Internet is often said to follow a Zipf-like distribution. Different Measurement studies showed, however, significantly different distributions depending on the Measurement methodology they followed. We performed a large-Scale Measurement of the most popular peer-to-peer (P2P) content distribution system, BitTorrent, over eleven months. We collected data on a daily to weekly basis from 500 to 800 trackers, with information about 40 to 60 million peers that participated in the distribution of over 10 million torrents. Based on these Measurements we show how fundamental characteristics of the observed distribution of content popularity change depending on the Measurement methodology and the length of the observation interval. We show that while short-term or small-Scale Measurements can conclude that the popularity of contents exhibits a power-law tail, the tail is likely exponentially decreasing, especially over long time intervals.
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IPTPS - Power-law revisited: large Scale Measurement study of P2P content popularity
2010Co-Authors: Gyorgy Dan, Niklas CarlssonAbstract:The popularity of contents on the Internet is often said to follow a Zipf-like distribution. Different Measurement studies showed, however, significantly different distributions depending on the Measurement methodology they followed. We performed a large-Scale Measurement of the most popular peer-to-peer (P2P) content distribution system, BitTorrent, over eleven months. We collected data on a daily to weekly basis from 500 to 800 trackers, with information about 40 to 60 million peers that participated in the distribution of over 10 million torrents. Based on these Measurements we show how fundamental characteristics of the observed distribution of content popularity change depending on the Measurement methodology and the length of the observation interval. We show that while short-term or small-Scale Measurements can conclude that the popularity of contents exhibits a power-law tail, the tail is likely exponentially decreasing, especially over long time intervals.
Yuefeng Wei - One of the best experts on this subject based on the ideXlab platform.
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Hydrodynamic Verification on the Motion Characteristics of FPSO Based on the Full Scale Measurement Data Features of Current and Wind
29th International Conference on Ocean Offshore and Arctic Engineering: Volume 1, 2010Co-Authors: Wenhua Zhao, Jianmin Yang, Yuefeng WeiAbstract:FPSO is subjected to complex sea loads during its service life. Series of coupled hydrodynamic analysis in time domain for FPSO and its mooring system have been conducted within the recent ten years. Among these analyses, the coefficients of wind force and current force for FPSO hull were calculated by the empirical formulae mostly. It is known that these coefficients are of great importance in the motion predictions of the FPSO in the analysis. The verification of the feasibility of these formulae is necessary. In this paper, the feasibility and the accuracy of these empirical formulae are verified through the comparison between the results of hydrodynamic analysis and those of full Scale Measurement data. A full Scale Measurement project sponsored by CNOOC for Nanhai Fenjin, an FPSO operating in South China Sea, has been carrying out by Shanghai Jiao Tong University since Oct 2007. Large amount of valuable data of the six-degree motions for the FPSO has been obtained. To do the comparison, a typical serious sea state is selected out to be the objective course. In the course, the response spectrums for heave, roll and pitch motions are calculated based on the Measurement data. Besides, a series of coupled hydrodynamic analysis for the FPSO are conducted, using the code DeepC. The response spectrums of the motions for heave, roll and pitch in the same sea state are also obtained through the spectrum analysis. Using these motion spectrums, comparisons between the results of hydrodynamic analysis and those of full Scale Measurement are fulfilled. With the comparisons, the feasibility of the empirical formulae of the coefficients for wind force and current force are verified. The correction coefficients are added to the empirical formulae and new hydrodynamic analysis based on the new formulae are conducted. It is shown that the new analysis results are in good agreement with those of the full Scale Measurement, which validated the practicability and feasibility of the modified formulae on the motion prediction of FPSO.Copyright © 2010 by ASME
Hlm Eric Wijen - One of the best experts on this subject based on the ideXlab platform.
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Full Scale Measurement of wind induced pressures : 1 configuration of wind induced pressures
1994Co-Authors: Cpw Chris Geurts, Hlm Eric WijenAbstract:A research project 10 the spectral characteristics of wind induced pressures is in progress in Eindhoven. This project includes both wind tunnel and full Scale Measurements. Wind induced pressures are measured in full Scale at the main building of Eindhoven University of Technology. This paper describes the building, environment and the equipment, that is used. Results will be presented at the conferences on Wind Engineering (e.g. [II, [21 and [3)).
