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81.
A new method for the estimation of basin-scale distribution of pressure of carbon dioxide on the sea surface (pCO2) by satellite-derived sea surface temperature (SST) and chlorophyll-a concentration (Chla) is presented. 28?557 shipboard pCO2 data were regressed by second-order multiple regression equations of SST and Chla with a regression error of ±14?µatm and ±17?µatm in the subtropical and subarctic domain, respectively. The monthly-average SST and monthly-maximum Chla (Chlmax) field determined from the Advanced Earth Observing Satellite/Ocean Color Temperature Scanner (ADEOS/OCTS) level 3 Daily Binned Map data were substituted into the multi-regression equation to generate the ‘monthly-typical’ basin-scale pCO2 field in the North Pacific, and the results agreed well with the climatological field of shipboard pCO2 observations with an error bar of ±21?µatm except in the case of springtime subarctic North Pacific. The satellite-pCO2 field also satisfactorily reproduced the principle distribution of pCO2 in the springtime subarctic North Pacific such as the location of each low-pCO2 patch observed by the shipboard measurements. The extent of pCO2 depletion in each pCO2 patch, however, was not well approximated by the satellite-pCO2 field. This was caused by the underestimation of Chlmax in these low-pCO2 patches due to the low frequency of satellite-Chla observations in the springtime subarctic North Pacific due to the cloudiness.  相似文献   
82.
The fast-discretization is known as an approximate but efficient technique for design and analysis of sampled-data systems. In this paper, we propose a fast-discretization-based design for sampled-data critical control systems. Supposing a tracking problem or a slow-changing disturbance rejection problem, we assume that an exogenous input is a persistent and/or transient input with bound on the rate of change. It is shown that the critical constraint for such exogenous inputs can be given in the form of the inequality constraint on the unit step response. The design parameters are determined by a numerical search method subject to this constraint. However, instead of evaluating it strictly, we check the corresponding constraint which is obtained from the fast-discretized system. Although this approach is approximate, it provides an efficient numerical procedure for a computer-aided design. To show the validity of the proposed method, an example of a multi-objective critical control system design is presented.  相似文献   
83.
Much attention has been paid to the transformation of lower alkanes such as propane and butanes into aromatic hydrocarbons from both industrial and academic points of view. The aromatic hydrocarbons can be utilized as a booster for high octane number gasoline and are fundamental raw chemicals in petroleum chemistry. The activation of lower alkanes is an intriguing subject. In early work, Csicsery [1–5] described dehydrocyclodimerization of lower alkanes over bifunctional catalysts such as platinum on alumina and Cr2O3 on alumina.  相似文献   
84.
The authors have been working on natural language understanding based on the knowledge representation language L md and its application to robot manipulation by verbal suggestion. The most remarkable feature of L md is its capability of formalizing spatiotemporal events in good correspondence with human/robotic sensations and actions, which can lead to integrated computation of sensory, motory and conceptual information. This paper describes briefly the process from text to robot action via semantic representation in L md and the experimental results of robot manipulation driven by verbal suggestion. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   
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Ultrafine powders of the ZrO2-SiO2 system prepared by spraying aqueous mixed solutions of ZrO(NO3)2·2H2O and silicone oil into an ultrahigh temperature inductively coupled plasma (the spray-ICP technique) have been investigated in connection with particle growth and phase change caused by heat treatment. The prepared powders were composed of roundish ultrafine particles 10 to 20 nm in size, and their components were tetragonal ZrO2 (t-ZrO2) and amorphous SiO2 (a-SiO2).a-SiO2 alone did not crystallize below 1400° C, though the particles grew above 900° C.t-ZrO2 converted to monoclinic ZrO2 (m-ZrO2) above 400° C, also followed by particle growth. On the other hand composite powders oft-ZrO2 anda-SiO2 exhibited no particle growth below 1200° C. Above 1200° Ct-ZrO2 converted tom-ZrO2, and its amount decreased with an increase in SiO2 content. At 1400° C particle growth occurred, and the round particles of ZrO2 were dispersed in ana-SiO2 glass medium. These results indicate that ZrO2 and SiO2 mutually block particle growth, and that SiO2 contributes to the quenching oft-ZrO2 by keeping the particles of ZrO2 within the critical particle size oft-ZrO2.  相似文献   
87.
SrBi 2 Ta 2 O 9 thin films were prepared by ECR plasma enhanced metalorganic chemical vapor deposition (ECR-MOCVD) with a liquid-delivery system using one cocktail source without an additional solvent. The strontium-tantalum double alkoxide, Sr{Ta[OC 2 H 4 H(CH 3 ) 2 ](OC 2 H 5 ) 5 } 2 , was dissolved in stabilized trimethyl bismuth, Bi(CH 3 ) 3 / dioxane. This source system has been used in a conventional bubbling system. Deposition rate and the composition of the films were strictly controlled by the concentration and the composition of the cocktail source. Therefore, high reproducibility was realized by using this system. The constituent phase of the stoichiometric SBT film as-deposited at 500 C on a (111)Pt/TiO 2 /SiO 2 /Si substrate was a fluorite phase and transformed to the single phase of SBT by the post annealing at 800 C. It showed almost the same ferroelectricity as the stoichiometric composition film.  相似文献   
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Fv-4 is a mouse gene that dominantly confers resistance to infection with Friend murine leukemia virus (F-MuLV) (S. Suzuki, Jpn. J. Exp. Med. 45:473-478, 1975). Despite complete resistance to ecotropic MuLV infection in mice carrying the Fv-4 gene, it is known that cells carrying the resistance gene in tissue culture do not always show resistance as extensive as that in vivo (H. Yoshikura and T. Odaka, JNCI 61:461-463, 1978). To investigate the immunological effect on resistance in vivo, we introduced the Fv-4 gene into BALB/c nude mice (Fv-4-/- nude[nu/nu]) by mating them with Fv-4 congenic BALB/c mice (Fv-4r/r nude+/+) and examined the susceptibility of the F2 progeny to F-MuLV. All BALB/c nude mice without the Fv-4 gene (Fv-4-/- nude[nu/nu]) were permissive to F-MuLV and developed erythroleukemia within 2 weeks after virus inoculation. The BALB/c nude mice with the Fv-4 gene (Fv-4r/r nude[nu/nu]) did not develop leukemia, and no or little virus was detected in the spleen 7 weeks after virus inoculation. The resistance to F-MuLV was dominant in (Fv-4 congenic BALB/c x BALB/c nude) F1 mice with the Fv-4r/- nude(nu/+) genotype as strictly as in (Fv-4 congenic BALB/c x BALB/c) F1 mice with the Fv-4r/- nude+/+ genotype. However, almost all BALB/c nude mice with the Fv-4r/- nude(nu/nu) genotype developed the disease within 7 weeks, and the virus was detected in all of their spleens even in the mice without leukemia. These results show that the resistance caused by the Fv-4 gene is recessive in nude mice and dominant in BALB/c mice. Some immunological effects, perhaps cell-mediated immunity, may play important roles in the resistance to F-MuLV infection in vivo in addition to the dosage effect of the Fv-4 product.  相似文献   
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