Technology Development for Lunar Thermal Applications and the Next Generation of Space Exploration

Author(s):  
E A Silk ◽  
R Creel
Author(s):  
John F. Perkins ◽  
Richard H. Hopkins ◽  
Charles D. Brandt ◽  
Anant K. Agarwal ◽  
Suresh Seshadri ◽  
...  

Several organizations, including Westinghouse, CREE, and ATM, as well as researchers in Japan and Europe, are working to develop SiC power devices for reliable, high power and high temperature environments in military, industrial, utility, and automotive applications. Other organizations, such as NASA Lewis and several universities, are also doing important basic work on basic SiC technology development. It has been recognized for two decades that the superior properties of SiC lead to range of devices with higher power, greater temperature tolerance, and significantly more radiation hardness than silicon or GaAs. This combination of superior thermal and electrical properties results in SiC devices that can operate at up to ten times the power density of Si devices for a given volume. Recent research has focused on the development of vertical metal oxide semiconductor field effect transistor (VMOSFET) power device technology, and complementary high speed, temperature-tolerant rectifier-diodes for power applications. We are also evaluating applications for field control thyristors (FCT) and MOS turn-off thyristors (MTO). The technical issues to be resolved for these devices are also common to other power device structures. The present paper reviews the relative benefits of various power devices structures, with emphasis on how the special properties of SiC enhance the desirability of specific device configurations as compared to the Si-based versions of these devices. Progress in SiC material quality and recent power device research will be reviewed, and the potential for SiC-based devices to operate at much higher temperatures than Si-based devices, or with enhanced reliability at higher temperatures will be stressed. We have already demonstrated 1000V breakdown, current densities of 1 kA/cm2, and measurements up to 400°C in small diodes. The extension of this work will enable the implementation of highly distributed aircraft power control systems, as well as actuator and signal conditioning electronics for next generation engine sensors, by permitting electronic circuits, sensors and smart actuators to be mounted on or at the engine.


2007 ◽  
Vol 2007.3 (0) ◽  
pp. 1-2
Author(s):  
Eisaku ITO ◽  
Keizou TSUKAGOSHI ◽  
Akimasa MUYAMA ◽  
Junichirou MASADA ◽  
Ikuo OKADA ◽  
...  

Author(s):  
Junji Adachi ◽  
Shunichi Adegawa ◽  
Keiichi Aoyagi

MEMS industry in Japan has successfully taken off and been expected its rapid expansion, and is classified as a priority technology in the 3rd Science and Technology Basic Plan. Further involvement from the government in support technology development and commercialization is essential to achieve competitive advantage of the industry. In relation with the large anticipation of MEMS industry, Micromachine Center recently launched MEMS Industry Forum (MIF) in order to support MEMS industry development in collaboration with the government, the academia and the industry. Primary activities of MIF are policies proposal to the government, supporting the national project implementation, education, MEMS foundry service network and so on. The new national project, conducted by New Energy and Industrial Technology development Organization (NEDO), launched in July, 2006. The project focuses upon technology development on highly integrated MEMS, such as MEMS/MEMS, CMOS/MEMS and Nano/MEMS integrations, and its final goal is to commercialize the next generation MEMS devices and systems in five to ten years.


2021 ◽  
Vol 10 (78) ◽  

Textiles made of organic fibers, include anthropologic knowledge about lifestyle, art idea, mythology, daily life and religious traditions of the culture made them. These tangible examples of Cultural identity of the society important for transfer traditional knowledge from next generation. Textile Cultural artefacts responsibility and interest of conservation and restoration science professionals can find from archaeological excavations or gathering from urban areas and given to museums from collectors. Historic textiles are hard to found well preserved and hard to passing it onto the next generation compared to artefacts made from inorganic materials because of they made of organic materials. Every country on the earth has their own definition of Cultural Heritage and preservation laws. Under this diversity in the field of conservation and restoration science, it is necessary to establish standard definitions and use a common language at academic field likewise in every profession. Ethical codes and principles made for conservation of Cultural Heritage are a guide for conservation professionals. Politics of conservation practices change by technology development. In recent years, by analytical research, has been noticed that active conservation activities can damage the cultural heritage hence passive conservation activities like documentation and preservative conservation becomes priority. Descriptive scanning model based on screening of literature related to textile conservation was adopted for this paper. Keywords: Cultural heritage, archaeological textile, conservation, restoration, ethics


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