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Tokyo, Japan

Tokyo Polytechnic University is a private university in Honchō, Nakano, Tokyo. Its nickname is Shadai . It was formerly known as Tokyo College of Photography .The university was founded as Konishi Professional School of Photography in Shibuya in 1923. The founder, Rokuemon Sugiura VII, was the president of Konishi Main Shop at that time and founded the school to fulfil the wish of Rokuemon Sugiura VI, the previous president.Beginning in 2007, the university offers courses in manga studies and animation studies. Wikipedia.

Shibuya M.,Tokyo Polytechnic University
Optical Review | Year: 2014

The progress of science and technology has directly affected the development of lens optics, and the requirements for high-performance optics have been a driving force behind improvement in this field. I will introduce various improvements in lens optics in which I have had a hand, and which make me firmly believe that the development of lens optics will never cease, thus leading us to conclude that “Lens optics will be brilliant forever”. © 2014, The Optical Society of Japan. Source

Barone G.,Tokyo Polytechnic University | Pirrotta A.,University of Palermo
Engineering Analysis with Boundary Elements | Year: 2013

Evaluation of shear stresses distribution due to external shear forces applied to De Saint-Venant beams has been solved through Complex Variable Boundary Element Method properly extended, to benefit from advantages of this method, so far widely used for twisted solids. Extending the above method, further simplifications have been introduced such as those of performing line integrals only, instead of domain integrals. Numerical applications confirm accuracy and efficiency of the proposed extended version of the method, since the good agreement with results proposed in literature. © 2012 Elsevier Ltd. Source

Kim Y.,Tokyo Polytechnic University | Kanda J.,University of Tokyo
Journal of Wind Engineering and Industrial Aerodynamics | Year: 2010

Many studies on reducing across-wind responses of tall buildings have been investigated, mainly focusing on the effect of corner shape. And it is also known that changing section along the height through tapering or set-back could reduce across-wind responses of tall buildings. In this paper, to investigate the mechanism of aerodynamic force reduction, the wind tunnel tests for fluctuating pressure and fluctuating force were carried out. Two models with different tapering ratio of 5% and 10%, one set-backed model and one prototype square prism with side ratio of unity were employed under two typical boundary layers which represent suburban and urban flow condition. It is concluded that tapering or set-back helps to reduce the mean drag force and the fluctuating lift force. Reduction ratio increases as tapering ratio increases, and the set-backed model is more effective to reduce the fluctuating lift force than the tapered model with identical surface area, reducing the coefficients about 40% in suburban flow condition. And by tapering and set-back, the power spectra of wind pressures at sideward surface become wideband and the peak frequencies depend on height, which makes the correlation near the Strouhal component low or even negative. © 2010 Elsevier Ltd. Source

Ding Z.,Tongji University | Tamura Y.,Tokyo Polytechnic University
Journal of Wind Engineering and Industrial Aerodynamics | Year: 2013

Internal forces in cladding support components of large-span roof structures under wind loads were usually estimated only based on the local wind loads imposed on tributary areas. However, internal forces on such members depend not only on local behaviors caused by local wind loads but also on wind-induced overall behaviors of main structural frames. By ignoring the contribution of overall behaviors of main structural frames, internal forces in cladding support components may be underestimated following current wind load codes or recommendations. It is necessary to investigate the contributions of local and overall behaviors to improve the wind-resistant design of the cladding support component members on large-span roof systems. In this paper, a method was proposed to separate the internal forces of cladding support components due to wind-induced local and overall behaviors and investigate the corresponding contributions for the largest internal forces. Wind loads used for loading effects estimation were obtained based on wind pressures measured from a 1:400 scaled roof model under a boundary layer wind flow configuration. Wind loading effects considering wind-induced total behaviors (overall behaviors and local behaviors together) for axial force, bending moment and shear force were calculated by time-history analysis using finite element (FE) models of the prototype structure. Meanwhile, internal forces in cladding support components only considering local behaviors were extracted by using local wind loads based on quasi-static assumption. Finally, based on the contributions to the largest wind-induced internal forces resulting from the proposed method, a procedure for remedying the current wind load codes for such members were discussed. © 2013 Elsevier Ltd. Source

Yu B.-G.,Korea Institute of Energy Research | Matsui M.,Tokyo Polytechnic University | Yu G.-J.,Korea Institute of Energy Research
IEEE Transactions on Industrial Electronics | Year: 2011

Since islanding of photovoltaic (PV) generation can cause safety problems, it should be prevented. This paper proposes a correlation-based islanding-detection method (IDM) using current-magnitude disturbance for a PV system. As an islanding-detection index, this paper uses the correlation factor between current-magnitude disturbance and the corresponding inverter output voltage. The proposed IDM uses the characteristics in which the up/down current disturbance has a strong correlation with the PV output voltage when islanding occurs. The proposed method has fast islanding capability and high power quality. For verification of the proposed method, the simulated and experimental results of a 3-kW PV inverter by IEEE Std. 929-2000 and IEEE Std. 1547.1-2005 are provided. The proposed correlation technique can be used in other active antiislanding methods based on the correlation between the current and voltage after islanding occurs. © 2006 IEEE. Source

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