Hidden Hot Dark Matter as Cold Dark Matter

We show that hidden hot dark matter, hidden-sector dark matter with interactions that decouple when it is relativistic, is a viable dark matter candidate provided it has never been in thermal equilibrium with the particles of the standard model. This hidden hot dark matter may reheat to a lower temperature and number density than the visible Universe and thus account, simply with its thermal abundance, for all the dark matter in the Universe while evading the typical constraints on hot dark matter arising from structure formation. We find masses ranging from ~3 keV to ~10 TeV. While never in equilibrium with the standard model, this class of models may have unique observational signatures in the matter power spectrum or via extra-weak interactions with standard model particles.Comment: 5 pages, 1 figur

A general computer model for predicting the performance of gas sorption refrigerators

Projected performance requirements for cryogenic spacecraft sensor cooling systems which demand higher reliability and longer lifetimes are outlined. The gas/solid sorption refrigerator is viewed as a potential solution to cryogenic cooling needs. A software model of an entire gas sorption refrigerator system was developed. The numerical model, evaluates almost any combination and order of refrigerator components and any sorbent-sorbate pair or which the sorption isotherm data are available. Parametric curves for predicting system performance were generated for two types of refrigerators, a LaNi5-H2 absorption cooler and a Charcoal-N2 adsorption cooler. It is found that precooling temperature and heat exchanger effectiveness affect the refrigerator performance. It is indicated that gas sorption refrigerators are feasible for a number of space applications

VLSI Revisited - Revival in Japan

This paper describes the abundance of semiconductor consortia that have come into existence in Japan since the mid-1990s. They clearly reflect the ambition of the government - through its reorganized ministry METI and company initiatives - to regain some of the industrial and technological leadership that Japan has lost. The consortia landscape is very different in Japan compared with EU and the US. Outside Japan the universities play a much bigger and very important role. In Europe there has emerged close collaboration, among national government agencies, companies and the EU Commission in supporting the IT sector with considerable attention to semiconductor technologies. Another major difference, and possibly the most important one, is the fact that US and EU consortia include and mix partners from different areas of the semiconductor landscape including wafer makers, material suppliers, equipment producers and integrated device makers.semiconductors, Hitachi, Sony, Toshiba, Elpida, Renesas, Sematech, VLSI, JESSI, MEDEA, ASPLA, MIRAI, innovation system

SHANGHAI – FROM DEVELOPMENT TO KNOWLEDGE CITY

This report provides insights on the expansive development in Shanghai of human resources in higher education and the creation of a huge web of incubators, university science parks, district industrial parks, and various specialized development zones. With a total population of some 17 million and a GDP per capita of around US$3,000 the city planners expects that 2.5 per cent of its GDP will in 2005 be used for research and development. FDI in high technology and returning scientists in microelectronics illustrate the ambitions of Shanghai to become a knowledge city. More than 140 foreign-controlled R&D laboratories have already been established in Shanghai. Their number and sizes will increase and also involve more basic research as the IPR regime improves. Shanghai will emerge as innovative knowledge region on the world stage that before 2020 will be competing with other global knowledge regions such as the Oxford-London-Cambridge triangle by attracting talent and creating new knowledge. This report highlights a rapid and continued expansion of higher education in Shanghai that now has 59 colleges and universities with a total enrolment in 2004 of 600,000 students. The City has 10 universities which are included in the national list of Top-100 Universities which have been selected by the Ministry of Education to receive special treatment and extra resources. Three of a dozen Chinese universities with expectation to become recognized as world-famous research universities are located in Shanghai – Fudan University, Tongji University and Shanghai Jiaotong University. Fudan University Science Park and the School of Microelectronics at Fudan University provide examples of the changing character of the university system in Shanghai Linked to the development of human resources is a web of technological infrastructure of which Zhangjiang High-Technology Development Zone provides an illustration of ongoing efforts to integrate industrial production, research and university education. Shanghai is attracting overseas entrepreneurs in its advancing semiconductor industry, exemplified by SMIC with one of its bases in Zhangjiang High-Technology Development Zone, Shanghai is also attracting returning scientists to expand its IC knowledge base as exemplified by the School of Microelectronics at Fudan University, which has 600 graduate students.Human factors; Universities; Fudan University; Regional innovation System (RIS) Semiconductors; High Technology Parks; Overview of Science and Technology

VLSI REVISITED – REVIVAL IN JAPAN

This paper describes the abundance of semiconductor consortia that have come into existence in Japan since the mid-1990s. They clearly reflect the ambition of the government – through its reorganized ministry METI and company initiatives - to regain some of the industrial and technological leadership that Japan has lost. The consortia landscape is very different in Japan compared with EU and the US. Outside Japan the universities play a much bigger and very important role. In Europe there has emerged close collaboration, among national government agencies, companies and the EU Commission in supporting the IT sector with considerable attention to semiconductor technologies. Another major difference, and possibly the most important one, is the fact that US and EU consortia include and mix partners from different areas of the semiconductor landscape including wafer makers, material suppliers, equipment producers and integrated device makers.semiconductors; Hitachi; Sony; Toshiba; Elpida; Renesas; Sematech; VLSI; JESSI; MEDEA; ASPLA; MIRAI; innovation system

NINGBO: A REGIONAL CITY LEAPFROG INTO HI-TECH DEVELOPMENT

The dynamic development in Ningbo illustrates local changes that have their basis in government support and resources from all levels of government. The rapid development arises from a combination of excellent infrastructure, a strong private entrepreneurship and strong foreign direct Investment (FDI) to exploit the geographical location which will be further enhanced when the bridge, across Hangzhou Bay to Shanghai, is completed by 2008.Ningbo, a famous port city in China, reached in 2000 a population of six million. It is situated 100 kilometres from Hangzhou, the capital of Zhejiang province, and 150 kilometres across the water from Shanghai. In terms of geo-economics Ningbo is an integral part of the dynamic Yangtze Delta region; but Ningbo is also trying to develop its own niche based on its comparative advantage. This is an important feature of China’s regional development model. Ningbo is the native place of Ningbo Bird, the forerunner in China’s, as well as a strong contender in the global, mobile handset industry. Ningbo has traditionally been a location for car component industries with early development of spark plugs and car wheels. The Geely car company has used Ningbo for its national expansion The Ningbo car components industry is expanding fuelled by support from the mould industry and a number of private supplier entrepreneurs. There are three major moulding industry centres in China. The moulding industry in Ningbo now employs about 100,000 workers. Ningbo does not want to remain only in knowledge application but in knowledge creation too. To this end Ningbo has four national-scale development zones, one hi-tech zone and 10 provincial and municipal level development zones which cater to both shipping and trade sectors; it is widely using incubators to stimulate new technologies. The Ningbo Hi-Tech Park is an important hi-tech zone in the region. jointly developed by the Chinese Academy of Sciences and the Ningbo Municipal Government, it was opened in July 1999. In March 2004, the Chinese Ministry of Education approved the establishment of Ningbo-Nottingham China's first Sino-foreign university. The new university will be founded jointly by the University of Nottingham of Britain and the Zhejiang Wanli University in Ningbo with an investment of RMB600 million.Regional innovation system; local universities; industrial parks; incubators; clusters; industrial zones

Cosmological Limits on Hidden Sector Dark Matter

We explore the model-independent constraints from cosmology on a dark-matter particle with no prominent standard model interactions that interacts and thermalizes with other particles in a hidden sector. Without specifying detailed hidden-sector particle physics, we characterize the relevant physics by the annihilation cross section, mass, and temperature ratio of the hidden to visible sectors. While encompassing the standard cold WIMP scenario, we do not require the freeze-out process to be nonrelativistic. Rather, freeze-out may also occur when dark matter particles are semirelativistic or relativistic. We solve the Boltzmann equation to find the conditions that hidden-sector dark matter accounts for the observed dark-matter density, satisfies the Tremaine-Gunn bound on dark-matter phase space density, and has a free-streaming length consistent with cosmological constraints on the matter power spectrum. We show that for masses <1.5 keV no region of parameter space satisfies all these constraints. This is a gravitationally-mediated lower bound on the dark-matter mass for any model in which the primary component of dark matter once had efficient interactions -- even if it has never been in equilibrium with the standard model.Comment: 8 pages, 6 figures, 1 table; References added, Eq. 16 corrected, and appendix with surface of allowed dark-matter abundance adde

Morphing the CMB: a technique for interpolating power spectra

The confrontation of the Cosmic Microwave Background (CMB) theoretical angular power spectrum with available data often requires the calculation of large numbers of power spectra. The standard practice is to use a fast code to compute the CMB power spectra over some large parameter space, in order to estimate likelihoods and constrain these parameters. But as the dimensionality of the space under study increases, then even with relatively fast anisotropy codes, the computation can become prohibitive. This paper describes the employment of a "morphing" strategy to interpolate new power spectra based on previously calculated ones. We simply present the basic idea here, and illustrate with a few examples; optimization of interpolation schemes will depend on the specific application. In addition to facilitating the exploration of large parameter spaces, this morphing technique may be helpful for Fisher matrix calculations involving derivatives.Comment: 18 pages, including 6 figures, uses elsart.cls, accepted for publication in New Astronomy, changes to match published versio