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Quantum Dot Lasers for Optical Communication Grown by Metal-Organic Chemical Vapor Deposition HASHIMOTO Rei/KUSHIBE Mitsuhiro/EZAKI Mizunori A semiconductor laser with a quantum dot (QD) active region promises ultralow threshold current, temperature-insensitive threshold current density, and high-frequency modulation. Toshiba and the University of Tokyo have developed InAs QD lasers on GaAs substrate for 1.3 μm and 1.5 μm optical fiber communication. We improved the optical property of the InAs QD by embedding it in GaInNAs, and successfully achieved room-temperature lasing operation with the longest wavelength of 1.288 μm in QD lasers grown on GaAs substrate by metal-organic chemical vapor deposition (MOCVD). Innovative Circuit Technology for More Compact and Effective Inverters MOCHIKAWA Hiroshi/KOYAMA Tateo Insulated-gate bipolar transistors (IGBTs) are commonly used as the core device of inverters for AC motor drives. However, IGBTs have a limitation in terms of loss reduction because they produce a threshold voltage drop at the PN junction. Toshiba has taken up the challenge of overcoming this limitation so as to realize low-loss inverters, and developed an innovative circuit technology called "Recovery Assist." This new circuit technology has demonstrated the ability to improve power conversion efficiency to around 99%. This, in turn, allows inverters to be downsized. Moreover, the production of heat is minimized so that an inverter can be sufficiently cooled by only a small airflow. An experimental inverter incorporating this technology was fabricated that attained the world's highest power density of 10 W/cm3. New inverters with this technology have been applied to air conditioners, because they are particularly effective in light load mode. Lead-Free Solders with Excellent Solderability THAN TRONG Long/HISAZATO Yuji/NOMURA Fujio Toshiba has developed two types of lead-free solder with excellent solderability: a medium melting temperature Sn-Cu-Co type and a low melting temperature Sn-Ag-Cu-In-(Co,Ti) type, with melting points of 227 °C and 207°C, respectively. The addition of cobalt and titanium lowers the surface tension of the molten solder and enhances oxidation resistance, thus improving the wettability. It was found that cobalt diffused to the η(Cu6Sn5) phase and partially replaced tin to form a new metastable phase, η’(Cu6Sn4.2Co0.3). The wettability and flow-up ratio of the Sn-Cu-Co solder in flow processing was found to be comparable to those of the Sn-Ag-Cu type. The void defect ratio detected in integrated circuit (IC) packages reflowed using Sn-Ag-Cu-In-(Co,Ti) solder was about 3%, which is remarkably low in comparison with that of Sn-Ag-Cu or Sn-Ag-Cu-In solders. Risk Analysis and Safety Integrity Level Analysis Services for Plants, Machinery, and Equipment SAKUMA Akira/YONEKI Shinya/KUSHIBIKI Takeshi Following the establishment of the IEC 61508 international functional safety standard by the International Electrotechnical Commission, risk analysis has become obligatory and risk-based management has been expanding in the design of plants, machinery, and equipment. Toshiba provides risk analysis and support services for plants, machinery, and equipment to ensure conformity with the functional safety standard, applying probabilistic safety assessment techniques developed for nuclear power plants. We also provide estimations of the frequency of hazardous events and the safety integrity level (SIL) in accordance with the requirements of the functional safety standard. Future of Power System Monitoring Systems Using Network Computing Terminals TSUCHIYA Takehiko/SHONO Takaya/SEKIGUCHI Katsuhiko Power utilities are becoming increasingly interested in power system monitoring systems, influenced by a number of trends within the power industry that encompass a wide range of issues including utility deregulation, the introduction of distributed generation, and so on. Toshiba is engaged in a project to produce a monitoring system that will cover the entire power system (power generation, power transmission, transformation of electrical energy, distribution, distributed generation, consumers) using network computing terminals structured within the same architecture. Shipment of 235.5 MVA Air-Cooled Generator for Manzhouli Project, PRC SAITO Kazumasa/KAKIUCHI Mikio/FUJITA Masafumi Toshiba shipped an advanced air-cooled generator for the Manzhouli Project in the People's Republic of China (PRC) in June 2006. This project has been advanced with Harbin Electric Machinery Co., Ltd. The generator features downsizing and higher performance in comparison with conventional air-cooled generators. The latest technologies were used in its design and manufacturing, and it has been confirmed to have successfully achieved the design specifications. Web Service Flow Controller Enabling Orchestration of Web Services OMORI Yoichi/MOCHIZUKI Katsuhito Toshiba TEC Corp. has developed a Web service flow controller, containing an execution engine and a development environment, based on a standard Web service orchestration language called BPEL4WS (Business Process Execution Language for Web Services). It runs on our CrossMissionTM middleware. The Web service flow controller enables cooperation with legacy Windows processes. A business process designer can design business logic without knowing the difference between Internet-based Web services and legacy processes. The Web service flow controller also supports both the password certification and encryption functions of the Web service security standard WS-Security. Therefore, our proposed mechanism allows Internet and intranet systems based on service-oriented architecture (SOA) to be easily developed. |