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31.
Some functional lanthanide metal complexes, such as acetylacetonato complexes, ethylenediaminetetraacetato complexes, were successfully applied for diagnostic technique. The authors are interested in investigating the structure and bonding in lanthanide and actinide metal complexes using 166Er, t55Gd, and 237Np Mtissbauer spectroscopies in connection with single-crystal and/or powder X-ray diffraction, making clear the differences on their structures as well as the differences in the participation of 4f and 5f orbitals in the chemical bonds. In this article, the crystal structures of two novel Gd(Ⅲ) acetylacetonato complexes, Gd(pta)3 · 2H2O (pta = 1,1,1 -trifluoro-5,5-dimethy 1-2,4-hexanedione) and Gd(bfa)3 · 2H2O (bfa = 1, 1, 1 -trifluoro-4-phenyl-2-4-butanedione) were reported. Though both of them were dihydrate and had distorted square antiprismatical structure, Gd(pta)3 · 2H2O crystallizes in the P 2 1/n (#14) monoclinic space group and its lattice parameters are a = 1.4141(6) nm, b = 1.0708(3) nm, c =2.2344(4) nm, β =952.4(2)°, and Gd(bfa)3· 2H2O crystallizes in P 212121 orthorhombic space group and its lattice parameters were a = 1.322 (1) nm, b = 2.295 (1) nm, c = 1. 0786(8) nm. In the meantime, the authors had finished a systematic investigation on the ^155Gd Mossbauer isomer shift (δ) of various Gd(Ⅲ) metal complexes having a different coordination number (C.N.) and different ratios coordinating oxygen to nitrogen. A tendency for the 6 value to decrease with an increase in the C.N, and the number of the nitrogen atom coordinating to Gd was confirmed. This indicated that the Gd-O and/or Gd-N bond in the investigated Gd(Ⅲ) metal complexes had a small covalent contribution, which was possible to be deduced from the O and/or N atoms of the lisands donating electrons to 6s, 5d, and 4f orbitals of Gd. 相似文献
32.
RIYANTO T. BAMBANG E. SHIMEMURA K. UCHIDA 《International journal of systems science》2013,44(11):1997-2017
Dual problems, which we call output and input variance constrained H2 /H∞ controls, are considered. In these problems, we seek control-laws that satisfy mixed H2 /H∞ performance criteria, under multiple variance constraints on either outputs or inputs of time-invariant multivariable systems. The approach taken is to convert the problems into non-linear programming with both equality and inequality constraints. For both problems, the Kuhn-Tucker optimality condition is employed to obtain a first-order necessary condition for a regular point that minimizes an upper bound on the quadratic performance for the given H∞ constraint. A second-order necessary condition and sufficiency for the strict local minimizer of the upper bound are investigated. Efficient algorithms for synthesizing the desired controllers are proposed. 相似文献
33.
Kimihiro Yamanaka Takafumi Ooyoshi Takayuki Nejime 《Journal of Materials Science: Materials in Electronics》2010,21(1):53-57
Measuring the real temperature of a flip chip solder joint during an electromigration test has been a problem because of its
small size and the local Joule heating due to a large applied current. A unique method that employs the electrical resistance
change in the junction line between two solder joints was introduced to determine the temperature of the solder joint. The
change in resistance was converted into temperature using a thermal coefficient of resistance of the junction line. The method
accurately measured temperatures of the solder joint within 2 K until the solder joint resistance change ratio reached 100%
due to growth of an electromigration void. 相似文献
34.
Satoshi Azuma Hisanori Yamasaki Daisuke Itoh Takafumi Maruyama 《Electrical Engineering in Japan》2008,165(4):84-91
A newly proposed energy‐compensating active control is implemented to reduce the return current noise which is caused by inverter‐driven electric car systems. The energy‐compensating active control detects the energy charged at the filter capacitor, and reduces the energy and current of the noise frequency component by simple feedback loop incorporated with the conventional motor torque controller. No additional sensors or circuit arrangements are necessary; therefore, the return current can be attenuated effectively without any further cost. The return current with an inverter system is measured using a current probe and an FFT analyzer, and it is shown that the 25‐Hz noise current is reduced by up to 10 dB with the control. The results reveal that the low‐frequency return current noise can be attenuated with the simple control scheme, which would expectedly reduce the size of filter reactors and capacitors to meet the current limit level of the signaling system's track relays. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(4): 84–91, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20615 相似文献
35.
According to Hebb's cell assembly theory, the brain has the capability of function localization. On the other hand, it is suggested that in the brain there are three different learning paradigms: supervised, unsupervised, and reinforcement learning, which are related deeply to the three parts of brain: cerebellum, cerebral cortex, and basal ganglia, respectively. Inspired by the above knowledge of the brain in this paper we present a brainlike learning system consisting of three parts: supervised learning (SL) part, unsupervised learning (UL) part, and reinforcement learning (RL) part. The SL part is a main part learning input–output mapping; the UL part is a competitive network dividing input space into subspaces and realizes the capability of function localization by controlling firing strength of neurons in the SL part based on input patterns; the RL part is a reinforcement learning scheme, which optimizes system performance by adjusting the parameters in the UL part. Numerical simulations have been carried out and the simulation results confirm the effectiveness of the proposed brainlike learning system. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(1): 32–39, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20600 相似文献
36.
Kimihiro Yamanaka Teruya Fujisaki Manabu Ichinose Takafumi Ooyoshi 《Journal of Materials Science: Materials in Electronics》2010,21(9):943-949
Build-up substrates have been preferable solutions for small and high performance systems for more than a few decades. Micro-vias
need to be smaller to realize ever higher wiring density in build-up substrates, but there has been concern on the reliability.
This paper focuses on Cu filled micro-vias of 25 μm in diameter and investigates the strain on micro-vias using a finite element
method for varying geometric parameters and material properties. The strain becomes smaller with shrinking micro-vias, and
a prediction equation for the strain is developed as a function of the aspect ratio and material properties for both single
and stacked micro-vias. 相似文献
37.
SUNAO MORI AKIKO UCHIDA SHUHEI YAMAMOTO ASMA SULTANA RYUICHI TATSUMI WATARU MIZUNOYA ATSUSHI SUZUKI YOSHIHIDE IKEUCHI 《Journal of Food Biochemistry》2007,31(3):328-342
This study evaluated the effect of high pressure on rabbit skeletal muscle, specifically on the production of inosinic acid (IMP), one of “umami” components, and on the activity of adenosine triphosphate (AMP) deaminase, which plays a role in the conversion of AMP to IMP. By increasing the pressure (0.1 to 300 MPa), nucleotide analysis showed that IMP content in muscle increased instantly with a concomitant decrease in ATP content. The IMP content of muscle at 300 MPa was approximately 15% higher than with lower pressures (0.1–200 MPa) when stored for 1 week at 4C after pressurization. These results suggested that the metabolism of nucleotides in muscle was not significantly impaired by pressure treatment. At 300 MPa, AMP deaminase maintained approximately 70% of the activity at 0.1 MPa. In contrast, the activity of purified AMP deaminase was completely lost at 200 MPa, and irreversible conformational changes were observed by in situ fluorescence spectroscopy. These results indicated that purified AMP deaminase was irreversibly denatured under pressure as high as 300–400 MPa. 相似文献
38.
Takafumi Kawaguchi Hiroyuki Nishimura Fumiaki Miwa Kazuhiro Abe Takashi Kuriyama Ikuo Narisawa 《Polymer Engineering and Science》1999,39(2):268-273
The environmental stress cracking (ESC) of acrylonitrile-butadiene-styrene (ABS) copolymer caused by a non-ionic surfactant (poly-oxyethylene alkylether) was studied by constant-load tensile creep tests and edge crack tension (ECT) tests. The fracture surfaces were investigated by a scanning electron microscope (SEM) and the morphology of the crack tip was investigated by a transmission electron microscope (TEM). It was found that the results of the creep tests performed in the non-ionic surfactant were very different from those performed in air. SEM images of the fracture surfaces showed that there were three different mechanisms of fracture and that specimens had a tendency to rupture by ESC when the stress was small. The results of the ECT tests and the TEM images showed that the change in the mechanism of the fracture was attributable to the change of morphology at the crack tip. 相似文献
39.
Yoshihito Nakagawa Yukihiro Akao Kohei Taniguchi Akemi Kamatani Tomomitsu Tahara Toshiaki Kamano Naoko Nakano Naruomi Komura Hirokazu Ikuno Takafumi Ohmori Yasutaka Jodai Masahiro Miyata Mistuo Nagasaka Tomoyuki Shibata Naoki Ohmiya Ichiro Hirata 《International journal of molecular sciences》2015,16(1):1526-1543
Accumulating data indicates that certain microRNAs (miRNAs or miRs) are differently expressed in samples of tumors and paired non-tumorous samples taken from the same patients with colorectal tumors. We examined the expression of onco-related miRNAs in 131 sporadic exophytic adenomas or early cancers and in 52 sporadic flat elevated adenomas or early cancers to clarify the relationship between the expression of the miRNAs and the endoscopic morphological appearance of the colorectal tumors. The expression levels of miR-143, -145, and -34a were significantly reduced in most of the exophytic tumors compared with those in the flat elevated ones. In type 2 cancers, the miRNA expression profile was very similar to that of the exophytic tumors. The expression levels of miR-7 and -21 were significantly up-regulated in some flat elevated adenomas compared with those in exophytic adenomas. In contrast, in most of the miR-143 and -145 down-regulated cases of the adenoma-carcinoma sequence and in some of the de novo types of carcinoma, the up-regulation of oncogenic miR-7 and/or -21 contributed to the triggering mechanism leading to the carcinogenetic process. These findings indicated that the expression of onco-related miRNA was associated with the morphological appearance of colorectal tumors. 相似文献
40.
Pedestrian protection has played an important role for driver assistance systems. Our aim is to develop a video based driver assistance system for the detection of the potentially dangerous situation between the vehicle and pedestrian, in order to warn the driver. In this paper, we address the problem of detecting pedestrian in real-world scenes and estimation of the walking direction with a single camera from a moving vehicle. Considering all the available cues for predicting the possibility of collision is very important. The direction in which the pedestrian is facing is one of the most important cues predicting where the pedestrian may move in the future. So we first address the problem of single-frame pedestrian orientation estimation in real-world scenes. Then again, we estimate the pedestrian walking direction using multi-frame based on the result of single-frame orientation estimation. We propose a three-step method: pedestrian detection for single-frame step, orientation estimation for single-frame step and walking direction estimation for multi-frame step. To evaluate the proposed method in its robustness and accuracy, the experiments have been performed between numbers of images which is highly challenging uncontrolled conditions in real world. It shows a significant performance improvement in octant orientation estimation of about 64% accuracy in the orientation estimation step and achieved surprisingly good accuracy in estimating the walking direction against 212 targeted objects. 相似文献