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21.
A tapped delayed line adaptive array antenna (TDL-AAA) and a space-temporal simultaneous processing equalizer (ST-SPE) are proposed as simple space-temporal equalizers based on minimum mean square error (MMSE) criterion. The ST-SPE has a compact hardware with a small number of taps compared to that of the TDL-AAA. The ST-SPE can reduce the computational complexity of the space-temporal joint equalization and it works effectively under the minimum phase condition such as appeared at line-of-sight (LOS) propagation environments at a high antenna height base station. However the ST-SPE cannot work under a non-minimum phase condition caused under N-LOS (non-line-of-sight). On the other hand, the TDL-AAA whose reference signal is synchronized at the center tap (TDL-AAAC) can work even in the non-minimum phase condition. In this paper, we propose a dual-mode space-temporal simultaneous processing equalizer (Dual-mode ST-SPE) which has a simple configuration and also works in non-minimum phase condition. The Dual-mode ST-SPE can reduce the computational complexity compared to the TDL-AAAC. Yoshihiro Ichikawa received the B.E. degree in department of communication engineering, in National Defense Academy in 1995, and M.E. and D.E. degree from Ibaraki University in 2001 and 2004, respectively. He joined the Japan Air Self Defense Force in 1995. His research interests are an adaptive algorithm, an antenna design, and an adaptive array antenna. Shigeki Obote received his B.E., M.E. and D.E. degrees in electrical and electronic engineering from Tottori University, Tottori, Japan, in 1996, 1998 and 2000, respectively. Since 2000, he has been with department of media and telecommunications engineering, faculty of engineering, Ibaraki University, Ibaraki, Japan, where he is currently a associate professor. His research interests are in adaptive array antenna and wireless communications systems. Kenichi Kagoshima received the B.E., M.E. and D.E. degrees in electronics engineering from the Tokyo Institute of Technology, Tokyo, Japan, in 1969, 1971, and 1974, respectively. He joined the Nippon Telegraph and Telephone Corporation (NTT) Laboratory in 1974 and researched and developed many kinds of radio communication antennas. Since 1997, he has been a professor at Ibaraki University, Ibaraki, Japan. Dr. Kagoshima was a Secretary and Treasure, Vice Chairman, and Chairman of the IEEE AP-S Tokyo Chapter in 1992, 1993, and 1994, respectively. He was a chair of antennas and propagation professional group of IEICE in 1999 and 2000. In 1973, he received the Yonezawa Prize for Young Engineers and 1998, best paper award from IEICE, respectively.  相似文献   
22.
Developing photoactivatable theranostic platforms with integrated functionalities of biocompatibility, targeting, imaging contrast, and therapy is a promising approach for cancer diagnosis and therapy. Here, we report a theranostic agent based on a hybrid nanoparticle comprising fullerene nanocrystals and gold nanoparticles (FGNPs) for photoacoustic imaging and photothermal therapy. Compared to gold nanoparticles and fullerene crystals, FGNPs exhibited stronger photoacoustic signals and photothermal heating characteristics by irradiating light with an optimal wavelength. Our studies demonstrated that FGNPs could kill cancer cells due to their photothermal heating characteristics in vitro. Moreover, FGNPs that are accumulated in tumor tissue via the enhanced permeation and retention effect can visualize tumor tissue due to their photoacoustic signal in tumor xenograft model mice. The theranostic agent with FGNPs shows promise for cancer therapy.  相似文献   
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In this article, two kinds of perfluoropolyether (PFPE) with different terminal groups were investigated using thermogravimetric analysis (TGA), infrared (IR) spectroscopy, gel permeation chromatography (GPC), and gas chromatography/gas mass spectrum (GC/MS) analysis. PFPEs with a hydroxyl or carboxylic acid terminal group were more heat stable than was PFPE with carboxylic methyl ester. Perfluoropropylene oxide-type PFPE with a perfluoroethyl terminal group at one end tends to lose weight more rapidly than does copolymer-type PFPE with dihydroxyl or dicarboxyl methyl ester terminal groups at both ends. The residual weight fraction of PFPE with a perfluoroethyl terminal group was dependent on the average molecular weight. The number-average molecular weight of PFPE can be calculated from the peak intensity ratio between the polar group and C F stretching by measuring the IR spectrum of PFPE. The number-average molecular weight of PFPE increased because of the evaporation loss of its low molecular weight fraction and the crosslinking reaction of PFPE with increase in temperature. GC/MS analysis showed that the main product of the pyrolysis of PFPE was hexafluoropylene. We speculated on the PFPE degradation mechanism and the optimum PFPE chemical structure in terms of heat stability. © 1996 John Wiley & Sons, Inc.  相似文献   
25.
This paper reports on the impingement cooling characteristics of a heat sink with thin longitudinal fins of 0.2 mm thickness, which are spaced with a fin-pitch in the range 0.5 mm to 2.0 mm. The air cooling of the heat sink comes from a slot-shaped orifice positioned above the heat-sink center. The breadth of the gap between the fin tops and the inlet orifice is in the range 0 mm to 10 mm. The thermal resistance of the thin longitudinal fins used is about 50% to 57% that of the thick longitudinal fins now in commercial use. The cooling performance of the thin-plate fins is almost the same as that of optimally arranged pin-fins with the same total surface area. A maximum value of six times the heat transfer rate of a single flat plate having the same base area was observed for the thin-plate fins. A comparison of cooling performance between impingement and channel flow systems was conducted. The performance of impingement cooling systems is almost unaffected by the breadth of the gap between the fin tops and the inlet orifice (or, for channel cooling, the upper wall). On the other hand, the performance of channel-cooling systems decreases significantly as the gap widens. © 1997 Scripta Technica, Inc. Heat Trans Jpn Res, 25(7): 449–459, 1996  相似文献   
26.
The paper presents two types of a passive safety containment for a near future BWR. They are named Mark S and Mark X containment. One of their common merits is very low peak pressure at severe accidents without venting the containment atmosphere to the environment. The PCV pressure can be moderated within the design pressure. Another merit is the capability to submerge the PCV and the RPV above the core level. The third merit is robustness against external events such as a large commercial airplane crash. Both the containments have a passive cooling core catcher that has radial cooling channels. The Mark S containment is made of reinforced concrete and applicable to a large power BWR up to 1830 MWe. The Mark X containment has the steel secondary containment and can be cooled by natural circulation of outside air. It can accommodate a medium power BWR up to 1380 MWe. In both cases the plants have active and passive safety systems constituting in-depth hybrid safety (IDHS). The IDHS provides not only hardware diversity between active and passive safety systems but also more importantly diversity of the ultimate heat sinks between the atmosphere and the sea water. Although the plant concept discussed in the paper uses well-established technology, plant performance including economy is innovatively and evolutionally improved. Nothing is new in the hardware but everything is new in the performance.  相似文献   
27.
Understanding the genetic factors of diabetes is essential for addressing the global increase in type 2 diabetes. HNF1A mutations cause a monogenic form of diabetes called maturity-onset diabetes of the young (MODY), and HNF1A single-nucleotide polymorphisms are associated with the development of type 2 diabetes. Numerous studies have been conducted, mainly using genetically modified mice, to explore the molecular basis for the development of diabetes caused by HNF1A mutations, and to reveal the roles of HNF1A in multiple organs, including insulin secretion from pancreatic beta cells, lipid metabolism and protein synthesis in the liver, and urinary glucose reabsorption in the kidneys. Recent studies using human stem cells that mimic MODY have provided new insights into beta cell dysfunction. In this article, we discuss the involvement of HNF1A in beta cell dysfunction by reviewing previous studies using genetically modified mice and recent findings in human stem cell-derived beta cells.  相似文献   
28.
One-year field experience of an 80 kW PV system on a rooftop of the ROHM Memorial VLSI Research Center at the Ritsumeikan University is reported. All kinds of live technology available materials, c-Si, poly Si and a-Si solar cells are installed on the three tilt angles of 26.5° south, horizontal and north 26.5°. Systematic PV performances have been measured from the beginning of June 2000 to the end of May 2001. Measurements were made mainly on DC output power from four kinds of PV arrays; c-Si south side, a-Si of horizontal and poly Si, a-Si north side. It has been shown from analyses of monthly data on each material that almost 70% of with that in the south side in the annual average. In summer a-Si module yields the maximum output power normalized to 1 kWp. On the contrary c-Si module shows larger output in winter. Some other unique results are demonstrated and discussed.  相似文献   
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Objectives: The aim of this study was to explore the potential of boosted tree (BT) to develop a correlation model between active pharmaceutical ingredient (API) characteristics and a tensile strength (TS) of tablets as critical quality attributes.

Methods: First, we evaluated 81 kinds of API characteristics, such as particle size distribution, bulk density, tapped density, Hausner ratio, moisture content, elastic recovery, molecular weight, and partition coefficient. Next, we prepared tablets containing 50% API, 49% microcrystalline cellulose, and 1% magnesium stearate using direct compression at 6, 8, and 10?kN, and measured TS. Then, we applied BT to our dataset to develop a correlation model. Finally, the constructed BT model was validated using k-fold cross-validation.

Results: Results showed that the BT model achieved high-performance statistics, whereas multiple regression analysis resulted in poor estimations. Sensitivity analysis of the BT model revealed that diameter of powder particles at the 10th percentile of the cumulative percentage size distribution was the most crucial factor for TS. In addition, the influences of moisture content, partition coefficients, and modal diameter were appreciably meaningful factors.

Conclusions: This study demonstrates that BT model could provide comprehensive understanding of the latent structure underlying APIs and TS of tablets.  相似文献   
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