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1.
2.
Closed-loop expressions for the minimum energy control of a single-input linear digital system are described. They are obtained by two different methods. The optimal inputs are given by state feedback with the bounded variable gains. The gains are independent of the initial state of the system 相似文献
3.
Takeshi Kondo Hiroyuki Ito Kazuhide Kusakabe Kazuhiro Ohkawa Kensuke Honda Yasuaki Einaga Akira Fujishima Takeshi Kawai 《Diamond and Related Materials》2008,17(1):48-54
The effect of CF4 plasma etching on diamond surfaces, with respect to treatment time, was investigated using scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and electrochemical measurements. SEM observations and Raman spectra indicated an increase in surface roughening on a scale of 10–20 nm, and an increase in crystal defect density was apparent with treatment time in the range of 10 s to 30 min. In contrast, alteration of the diamond surface terminations from oxygen to fluorine was found to be rather rapid, with saturation of the F/C atomic ratio estimated from XPS analysis after treatment durations of 1 min and more. The redox kinetics of Fe(CN)63−/4− was also found to be significantly modified after 10 s of CF4 plasma treatment. This behavior shows that C–F terminations predominantly affect the redox kinetics compared to the effect on the surface roughness and crystal defects. The double-layer capacitance (Cdl) of the electrolyte/CF4 plasma-treated boron-doped diamond interface was found to show a minimum value at 1 min of treatment. These results indicate that a short-duration CF4 plasma treatment is effective for the fabrication of fluorine-terminated diamond surfaces without undesirable surface damage. 相似文献
4.
Takeshi Kondo Sang Min Lee Michal Malicki Benoit Domercq Seth R. Marder Bernard Kippelen 《Advanced functional materials》2008,18(7):1112-1118
We report on a single‐layer organic memory device made of poly(N‐vinylcarbazole) embedded between an Al electrode and ITO modified with Ag nanodots (Ag‐NDs). Devices exhibit high ON/OFF switching ratios of 104. This level of performance could be achieved by modifying the ITO electrodes with some Ag‐NDs that act as trapping sites, reducing the current in the OFF state. Temperature dependence of the electrical characteristics suggest that the current of the low‐resistance state can be attributed to Schottky charge tunnelling through low‐resistance pathways of Al particles in the polymer layer and that the high‐resistance state can be controlled by charge trapping by the Al particles and Ag‐NDs. 相似文献
5.
Recently published studies indicate a potential clinical application of PET in head and neck tumors. In the preoperative staging phase, PET enables confirmation of regional lymph node extension and guides nodal neck dissection or systemic treatment. In this phase, a high negative predictive value, near 100%, could make it possible to avoid many negative neck dissections. This is a reliable technique for confirming or excluding the presence of recurrent/residual tumor and for obtaining an early evaluation of chemotherapeutic and radiotherapeutic response. PET imaging in many cases makes it possible to locate and guide histological study of tumors with an unknown primary. PET imaging for these indications is a perfect complementary method for clinical exploration and better than other imaging techniques. 相似文献
6.
The DNA binding selectivity of new dicationic ligands based on the bis(vinylpyridinium)benzene unit has been investigated by means of UV-Vis absorption spectroscopy. From the experimental results it is concluded that these extended pi-electron bridged viologens have relatively high affinity to AT base pair sequences whereas the binding to GC pairs is about 10 times lower, and binding affinity depends on minor variation in the ligand structure. Linear type ligand exhibits two binding mode interaction, intercalation at high dye concentration which undergoes switching to groove binding at low ligand concentration. 相似文献
7.
T Akahoshi T Nagaoka R Namai N Sekiyama H Kondo 《Canadian Metallurgical Quarterly》1997,16(6):231-235
The effects of monosodium urate (MSU) crystals on apoptosis of cultured peripheral blood neutrophils were investigated. MSU crystals at low concentrations decreased the rate of spontaneous apoptosis of neutrophils in a dose- and time-dependent manner. The culture supernatant of MSU crystal stimulated neutrophils also promoted a delay in neutrophil apoptosis. MSU crystals at higher concentrations rapidly caused cell lysis. These findings indicated that MSU crystals are capable of amplifying the inflammatory responses of gouty arthritis by decreasing the rates of neutrophil apoptosis at lower concentrations and inducing cell lysis at higher concentrations. 相似文献
8.
To study the time-course of infectious asthma, we retrospectively examined FEV1 from 5 days before to 10 days after the onset of illness in 31 asthmatic children (20 boys and 11 girls), aged 8 to 12 years. Infections were confirmed by a rise of at least fourfold in serum compliment fixation titers (respiratory syncytial virus, adenovirus, and Mycoplasma pneumoniae) and hemoagglutination inhibition titers (parainfluenza virus types 1, 2, and 3). All the patients had 20 percent or more fall in FEV1 from baseline value during acute phase, but were clinically tolerable and required minimum or no bronchodilators. Regardless of infectious agent, FEV1 began to fall on the first disease day or the previous day, and deteriorate for the first few days. Mean(SD) maximum fall in FEV1 ranged from 39(12) percent to 45(20) percent. Thereafter, FEV1 began to improve and returned to the preillness level by the seventh to tenth day. These results suggest that progressive bronchial obstruction may be inevitable during the acute stage of any infectious asthma. 相似文献
9.
Effect of hydrogen charging on dislocation behavior in Ni-Cr and Ni<Subscript>2</Subscript>Cr alloys
Kaori Miyata 《Metallurgical and Materials Transactions A》2003,34(6):1249-1257
The effects of hydrogen charging on the dislocation behaviour in Ni-Cr binary alloys have been investigated by means of transmission
electron microscope (TEM) observations using single-crystalline specimens. The deformation mode of Ni-Cr alloys in the absence
of hydrogen is characterized by planar dislocations. However, hydrogen charging changed the dislocation configurations to
promote curved dislocations, such as dislocation loops and dipoles. The hydrogen-affected dislocation configurations are enhanced
with increasing Ni content and reducing Cr content. Weak-beam images show that the Shockley partials of the hydrogen-affected
dislocations frequently constrict to make kinks and cross-slip, as if the dislocations were generated by a thermally activated
process. The effect of hydrogen charging on superdislocations of a Ni2Cr superstructure has been also investigated using an aged 70Ni-30Cr alloy. While the deformation mode in the Ni2Cr superlattice is classified as five variants of superdislocation triplets and one variant of ordinary dislocations, the
hydrogen charging has preferred the ordinary dislocations to the superdislocation triplets. The results suggest that the charged
hydrogen changes the local plasticity to affect the deformation dynamics in Ni-Cr alloys, where the influence of hydrogen
on the plasticity is sensitive to the Ni/Cr concentration and the symmetry of atomic arrangement. 相似文献
10.
Fukuda H. Ebara M. Kobayashi A. Sugiura N. Yoshikawa M. Saisho H. Kondo F. Yoshino S. Yahagi T. 《IEEE transactions on bio-medical engineering》1998,45(3):396-400
To objectively evaluate the parenchymal echo pattern of cirrhotic liver and chronic hepatitis, the authors applied an image analyzing system (IAS) using a neural network. Autopsy specimens in a water tank (n=13) were used to examine the relationship between the diameter of the regenerative nodule and the coarse score (CS) calculated by IAS. CS was significantly correlated with the diameter of the regenerative nodule (p<0.0001, r=0.966). CS is considered to be useful for evaluating the coarseness of the parenchymal echo pattern 相似文献