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Tokyo, Japan

Tokyo Electric Power Company, Incorporated , also known as Toden or TEPCO, is a Japanese electric utility servicing Japan's Kantō region, Yamanashi Prefecture, and the eastern portion of Shizuoka Prefecture. This area includes Tokyo. Its headquarters are located in Uchisaiwaicho, Chiyoda, Tokyo, and international branch offices exist in Washington, D.C., and London. It is a founding member of strategic consortiums related to energy innovation and research; such as JINED, INCJ and MAI.In 2007, TEPCO was forced to shut the Kashiwazaki-Kariwa Nuclear Power Plant after the Niigata-Chuetsu-Oki Earthquake. That year it posted its first loss in 28 years. Corporate losses continued until the plant reopened in 2009. Following the March 2011 Tōhoku earthquake and tsunami, its power plant at Fukushima Daiichi was the site of a continuing nuclear disaster, one of the world's most serious. TEPCO could face ¥2 trillion in special losses in the current business year to March 2012, and the Japanese government plans to put TEPCO under effective state control to guarantee compensation payments to the people affected by the accident. The Fukushima disaster displaced 50,000 households in the evacuation zone because of leaks of radioactive materials into the air, soil and sea.In July 2012 TEPCO received ¥1 trillion from the Japanese government. TEPCO's management subsequently made a proposal to its shareholders for the company to be part-nationalized. The total cost of the disaster was estimated at $100bn in May 2012. Wikipedia.

Tanaka Y.,Tokyo Electric Power Company
International Journal of Pressure Vessels and Piping | Year: 2012

Difficulties in handling dynamic load with elastic-plastic analysis and/or structural component test significantly exist in the field of R&D for seismic resistive nuclear pipe systems. In previous studies, the analyses and the structural tests were conducted statically. Many of them have been suggesting conservativeness included in the current seismic criterion of the nuclear design code. Therefore, if analogy between the earthquake load and static displacement are proved, it should bring possibility of more reasonable criterion. The author studied analogy between dynamic load and static displacement using FEM analysis with elastic beam model and elastic-plastic shell model of an elbow. First, the dynamic load equivalent to 160% of ASME/JSME Code's Level D limit was defined using the elastic beam model. Next, the defined dynamic load was given to the elastic-plastic shell model to acquire the non-linear behaviors such as the relative displacement trend and the plastic strain accumulation at crown of the elbow. Then, three cases of cyclic displacement trends, Case 1, 2 and 3, were defined base on the dynamic analysis results and given to the elastic-plastic shell model statically. Comparison between the dynamic analysis and the static analysis of Case 1 showed clear analogy between the dynamic load and the static displacement. Case 2, however, was found to be difficult to be judged at this moment. Case 3 was conservative throughout the loaded time and suggested possibility of the conservative displacement trend for static structural test without conducting the elastic-plastic analysis. © 2011 Elsevier Ltd.

Nakamura H.,Tokyo Electric Power Company
Allergology International | Year: 2011

Previous family studies suggested that genetic variation contributes to COPD susceptibility. The only gene proven to influence COPD susceptibility is SERPINA1, encoding α1-antitrypsin. Most studies on COPD candidate genes except SERPINA1, have not been consistently replicated. However, longitudinal studies of decline in lung function, meta-analyses of candidate gene studies, and family-based linkage analyses suggested that variants in EPHX1, GST, MMP12, TGFB1, and SERPINE2 were associated with susceptibility to COPD. A genome-wide association (GWA) study has recently demonstrated that CHRNA3/5 in 15q25 was associated with COPD compared with control smokers. It was of interest that the CHRNA3/5 locus was associated with nicotine dependence and lung cancer as well. The associations of HHIP on 4q31 and FAM13A on 4q22 with COPD were also suggested in GWA studies. Another GWA study has shown that BICD1 in 12p11 was associated with the presence or absence of emphysema. Although every genetic study on COPD has some limitations including heterogeneity in smoking behaviors and comorbidities, it has contributed to the progress in elucidating the pathogenesis of COPD. Future studies will make us understand the mechanisms underlying the polygenic disease, leading to the development of a specific treatment for each phenotype. © 2011 Japanese Society of Allergology.

Mori N.,Kyoto University | Takahashi T.,Kansai University | Yasuda T.,Kyoto University | Yanagisawa H.,Tokyo Electric Power Company
Geophysical Research Letters | Year: 2011

At 14:46 local time on March 11, 2011, a magnitude 9.0 earthquake occurred off the coast of northeast Japan. This earthquake generated a tsunami that struck Japan as well as various locations around the Pacific Ocean. With the participation of researchers from throughout Japan, joint research groups conducted a tsunami survey along a 2000 km stretch of the Japanese coast. More than 5300 locations have been surveyed to date, generating the largest tsunami survey dataset in the world. On the Sendai Plain, the maximum inundation height was 19.5 m, and the tsunami bore propagated more than 5 km inland. Along the ria coast from about 50 to 200 km north of Sendai, the narrow bays focused the tsunami waves, generating the largest inundation heights and run-ups. The survey data clearly show a regional dependence of tsunami characteristics. Copyright 2011 by the American Geophysical Union.

Akagi H.,Tokyo Institute of Technology | Isozaki K.,Tokyo Electric Power Company
IEEE Transactions on Power Electronics | Year: 2012

This paper describes a hybrid active filter intended for mitigating the line-side harmonic currents of a three-phase 12-pulse diode rectifier used as the front end of a medium-voltage high-power motor drive. This hybrid filter is characterized by series connection of a simple LC filter and a small-rated active filter. This circuit configuration brings low cost, small size, and light weight to the hybrid filter. A three-phase experimental system rated at 400 V and 15 kW is designed, constructed, and tested, which is a downscaled model of the medium-voltage motor drive system. In this experiment, the LC filter is tuned to the 11th-harmonic frequency, and the active filter is based on a three-level neutral-point-clamped pulsewidth modulation converter (NPC PWM) with a dc capacitor voltage as low as 28 V. This hybrid filter is connected on either first or fourth winding of a line-frequency transformer with a first Δ-winding voltage of 400 V in the primary, and a second Δ-winding voltage of 220 V, a third Y-winding voltage of 220 V, and a fourth Δ-winding voltage of 400 V in the secondary. Experimental results show that the hybrid filter performs satisfactory filtering in a range from no-load to full-load conditions. © 2011 IEEE.

Kataoka Y.,Tokyo Electric Power Company
IEEJ Transactions on Power and Energy | Year: 2013

This paper deals with estimation of total output of solar photovoltaic generators (PV's) widely distributed in future power systems. In the proposed framework of estimation, the estimated signal in each frequency band is a linear combination of observed signals. The observation gain for each observed signal in each frequency band is designed through following two steps. First, an estimation error function is defined using assumed root mean square of output of PV's, predicted distribution of future PV's in the area, and correlation coefficients, which are identified in advance based on actual synchronized measurements of PV's. Second, observation gain in each frequency band is designed so as to minimize the estimation error function. The appropriateness of the proposed framework of estimation is demonstrated in small scale and large scale examples. © 2013 The Institute of Electrical Engineers of Japan.

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