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This paper presents an algebraic approach to polynomial spectral factorization, an important mathematical tool in signal processing and control. The approach exploits an intriguing relationship between the theory of Gröbner bases and polynomial spectral factorization which can be observed through the sum of roots, and allows us to perform polynomial spectral factorization in the presence of real parameters. It is discussed that parametric polynomial spectral factorization enables us to express quantities such as the optimal cost in terms of parameters and the sum of roots. Furthermore an optimization method over parameters is suggested that makes use of the results from parametric polynomial spectral factorization and also employs two quantifier elimination techniques. This proposed approach is demonstrated in a numerical example of a particular control problem. 相似文献
23.
In the present paper, we report results of surveys in 2003 in Japan and Denmark about patients' views about adverse events, focusing on the actions of healthcare staff involved in a medical accident. Results show that patients were more likely to indicate negative expectations to a doctor's reactions after a medical accident when asked in general terms than when asked in relation to concrete case stories. When asked in general terms, 66% (47%) of Japanese (Danish) respondents expected that doctors sometimes hold back on providing information to patients about a medical accident, while 37% (7%) did so when asked about a concrete, mild-outcome case. We examine some possible reasons for the relatively high level of distrust of Japanese patients, and we discuss whether the seemingly lower level of disclosure in Japan than in Denmark and the negative stories in the Japanese press may have an impact. We also suggest some implications for introducing a patient-centred or customer-centred approach to risk management in healthcare and other domains. 相似文献
24.
Oxidation kinetics and x-ray diffraction of the intermediate products have been investigated for several kinds of Fe3 O4 powders during the oxidation to γFe2 O3 . From these results, a two-components-hypothesis as an intermediate state of the Fe3 O4 - γFe2 O3 system is proposed, instead of a homogenious solid solution which has been widely recognized. The effect of the changes in particle size caused by the two phases oxidation products on the variations of magnetic coercivity was emphasised. 相似文献
25.
Yasuhiro Kobayashi Masaaki Ohkita Michio Inoue 《Mathematics and computers in simulation》1976,18(2):115-122
For an analog simulating system, an approximating system is proposed. Its mathematical form is expressed by an algebraic equation: with four parameters given by real numbers. Their values can be determined so as to satisfy a best fit in a Chebyshev sense. Then, the accuracy is of the same order with that obtained by any kind of ordinary power series up to terms o f the third order. It is noticeable that a given function can be accurately approximated by this equation without destroying its uniform continuity.As its electronic system, it is possible to utilize forward current-voltage characteristics o f p-n diodes near their origins. Different functions can be produced by adjusting an amount o f ordinary resistances connected to diodes in series. 相似文献
26.
Nariaki Sakaba Kazuhiko Iigaki Masaaki Kondo Koichi Emori 《Nuclear Engineering and Design》2004,233(1-3):135
The containment structures of the HTTR consist of the reactor containment vessel, the service area, and the emergency air purification system, which minimise the release of fission products in postulated accidents, which lead to fission product release from the reactor facilities. The reactor containment vessel is designed to withstand the temperature and pressure transients and to be leak-tight in the case of a rupture of the primary concentric hot-gas duct, etc. The pressure inside the service area is maintained at a negative pressure by the emergency air purification system. The emergency air purification system will also remove airborne radioactivity and will maintain a correct pressure in the service area.The leak-tightness characteristics of the containment structures are described in this paper. The measured leakage rates of the reactor containment vessel were enough less than the specified leakage limit of 0.1%/d confirmed during the commissioning tests and annual inspections. The service area was kept in a way that the design pressure becomes well below its allowable limitation by the emergency air purification system, which filters efficiency of particle removal and iodine removal well over the limited values.The obtained data demonstrate that the reactor containment structures were fabricated to minimise the release of fission products in the postulated accidents with fission product release from the reactor facilities. 相似文献
27.
The shear properties of thin films of star and linear polyisoprene (PIP) melts under high pressure were investigated as a function of sliding velocity (shear rate) using the surface forces apparatus. The results were contrasted with their bulk rheological properties; effects of thickness constraint on the shear behavior were discussed. The melts of PIP in bulk exhibit Newtonian-like constant viscosity at least at low shear rates (frequencies), which suggests that individual molecules flow with lateral sliding motion. However, thin films of PIP melts show tribological features involving apparent shear-thinning behavior, indicative of the correlated motions in confined geometries. The shear-property change from bulk rheological behavior to thin-film tribological behavior along with the thickness decrease reflects the physical states and their transitions in the systems; the thickness constraint induces glasslike transitions. Effects of molecular weights and molecular architecture (star-branched or linear) on the shear properties are also discussed. 相似文献
28.
Takayoshi Yokoya Rikiya Yoshida Yuki Utsumi Koji Tsubota Hiroyuki Okazaki Takanori Wakita Yoshikazu Mizuguchi Yoshihiko Takano Takayuki Muro Yukako Kato Hiroshi Kumigashira Masaharu Oshima Hisatomo Harima Yoshihiro Aiura Hitoshi Sato Akihiro Ino Hirofumi Namatame Masaki Taniguchi Masaaki Hirai Yuji Muraoka 《Science and Technology of Advanced Materials》2012,13(5)
We have characterized the electronic structure of FeSe1−xTex for various x values using soft x-ray photoemission spectroscopy (SXPES), high-resolution photoemission spectroscopy (HRPES) and inverse photoemission spectroscopy (IPES). The SXPES valence band spectral shape shows that the 2 eV feature in FeSe, which was ascribed to the lower Hubbard band in previous theoretical studies, becomes less prominent with increasing x. HRPES exhibits systematic x dependence of the structure near the Fermi level (EF): its splitting near EF and filling of the pseudogap in FeSe. IPES shows two features, near EF and approximately 6 eV above EF; the former may be related to the Fe 3d states hybridized with chalcogenide p states, while the latter may consist of plane-wave-like and Se d components. In the incident electron energy dependence of IPES, the density of states near EF for FeSe and FeTe has the Fano lineshape characteristic of resonant behavior. These compounds exhibit different resonance profiles, which may reflect the differences in their electronic structures. By combining the PES and IPES data the on-site Coulomb energy was estimated at 3.5 eV for FeSe. 相似文献
29.
Ahmed AbdelMonteleb M. Ali Abdelazim M. Negm Mahmoud F. Bady Mona G. E. Ibrahim Masaaki Suzuki 《Clean Technologies and Environmental Policy》2016,18(4):1053-1068
Egypt in 2015 announced the alteration of the fuels used in cement plants without the least regard to minimizing the environmental burden (EB) excesses. This study conducts a life-cycle assessment (LCA) of Egyptian cement-manufacturing unit, which is considered as the first one on LCA cement analysis to be conducted in Egypt. This study investigates the LCA of the cement industry in Egypt compared to the Swiss industry, using two methodologies. The first one has been done on-site, surveying the most common types of cement used in the construction industry in Egypt. Meanwhile, SimaPro software has been used to assess the environmental impacts, and three different cement plants were selected for this study: an Egyptian cement plant (ECP) which uses electricity, natural gas, and diesel as energy sources; a Swiss cement plant (SCP) which depends mainly on electricity, natural gas, and coal; and an Egyptian hypothetical plant (EHP) in which electricity and coal are assumed to be the main energy feeds, and comparisons of different strategies including midpoint and endpoint methods are outlined. Regarding the midpoint method, ETP recorded higher respiratory inorganics, aquatic acidification, global warming, and nonrenewable energy impacts than ECP, because of using coal, while for SCP, global warming and respiratory inorganics achieved the highest adverse impacts compared to ECP and EHP—due to the different manufacturing technology used. With regard to the endpoint method, the peak possibility of human health deterioration has been recorded due to the use of coal as fuel. This possibility was reduced by 46 % in the case of SCP as a result of the technology applied, which interestingly represents a reasonable reduction in terms of technological application. 相似文献
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