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A Study on High Performance Gbps MIMO Wireless System
Get PDF九州工業大学博士学位論文 学位記番号:情工博甲第294号 学位授与年月日:平成26年12月25日1 Introduction||2 Wireless System Overview||3 RC4 Encryption Architectures||4 MIMO Detection Algorithm and Architecture||5 LDPC Decoder Architecture||6 Conclusion and Future Wor
AC loss of ripple current in superconducting DC power transmission cable
Get PDF26th International Symposium on Superconductivity (ISS 2013), November 18-20, 2013, Tokyo, JapanAs a method of largely reducing the transmission loss in the electric power grid, superconducting direct current (DC) power transmission cable has been investigated. Using superconducting DC power transmission cables, large amounts of current and energy can be transferred compared to conventional copper cables. In this case, an alternating current (AC) is converted to DC and superposed AC which is known as ripple current, and the energy loss by the ripple current is generated. Therefore it is desired to estimate the energy loss density for the case of DC current and superposed AC current for a design of DC transmission cable system. In this study, the hysteresis loss for DC current of 2 kA rectified from 60 Hz alternating current is calculated using the Bean model, and coupling loss was also estimated. The diameter of the cable was 40 mm. The ripple currents generated by multi-pulse rectifiers, 6-pulse, 12-pulse, and 24-pulse were considered. It is found that the total AC loss including the hysteresis loss and the coupling loss is considerably smaller than the supposed heat loss of 0.5 W/m which is obtained with a newly developed cable
A Pilot Survey about KIT Students’ Images of Globalization and their Suggestions for Education
Get PDFホームネットワークにおける電力線通信方式の高速化に関する研究
Get PDF九州工業大学博士学位論文 学位記番号:情工博甲第288号 学位授与年月日:平成26年3月25日第1章.序論||第2章 PLCの物理層||第3章 PLCの雑音環境での性能予測||第4章 広帯域PLC上のネットワーク連携形TCP高速化||第5章 非対称全2重方式PLCによるTCP高速化||第6章 PLC応用の今後の課
Thermal Stress Analysis for Ceramic Roll Composed by Shrink Fitting Dipped into Molten Metal
Get PDFThis paper deals with a large ceramics structure composed by shrink fitting used for rolls in molten
zinc. The ceramics roll may provide a longer life and reduce the cost for the maintenance because of large
heat resistance and large wear resistance. However, the small toughness of ceramics may cause fracture
because of the large thermal stress when the roll is dipping into the molten zinc. Moreover, since the shaft
and the sleeve are connected by shrink fitting, they may separate each other under high temperature when
dipping into the molten metal. In this paper, therefore, the thermal stress as well as separation is considered when the ceramics roll is composed by shrink fitting by the application of the finite volume method (FVM) and finite element method (FEM). Then, the values of maximum stress are discussed by considering
the shrink fitting system as well as the thermal stress
Characteristics of Process in Reconstruction of Commerce in Flood Dameged Businesses : Studies on the dynamics of reconstruction in heavy rain disaster
No full textThis study clarified the characteristics of process in reconstruction of commerce in flood damaged businesses by using “Revival Curve Chart” and “How-to-Repair Survey”. The major results are as following.
1. The process of reconstruction can be classified into three types with “steady”, “delayed”, “two stage” as the progress, and with “restoration”, “improvement”, “suitable” as the course, respectively.
2. The trend of reconstruction is generally decided depending on nine inner / external factors. Among them, “status of business of pre-disaster” and “age of merchants” work predominantly.
3. An altruistic action of struck shops supports the livelihoods reconstructing in the region in no small way
Compensation of Magnetic Saturation of self-sensing Magnetic Levitation
Get PDFThe 6th International Conference on Positioning Technology (Mechatronics and Measurement in Precision Technology) ICPT 2014, November 18-21, 2014, Kitakyushu International Conference Center, Fukuoka, JapanThis paper investigates the magnetic saturation problem of self-sensing electromagnetic levitation system and presents a novel self-sensing scheme. The proposed approach employs a demodulation technique. By superimposing a high frequency voltage, the resulting electromagnet coil currents have ripples that can be used for gap sensing. This paper shows the effect of magnetic saturation on the gap sensing and the gap length is not uniquely determined when using the relation between the ripple, control current and the gap in simulations. The results imply that the constraint conditions are to be determined to solve the problem. The proposed approach utilizes the dynamical motion model of the electromagnetic levitation system to uniquely identify the gap. By using the system behavior information, the gap can be uniquely estimated. To incorporate the dynamical model with the gap sensing algorithm, the unscented Kalman filter is employed. The proposed estimator is demonstrated in simulations. The results show that it is possible to deal with magnetic saturation by using the proposed gap sensing scheme. The estimator has a good accuracy in wide gap range compared to the conventional method
Fatigue properties and damage mechanism of modified PC based GFRP
Get PDFIn this study, for the matrix / fiber interface strength is investigated in the fatigue experiment for the glass-fiber reinforcing polycarbonate (GFPC). Here the effect of modified PC resin is discussed when Epoxy (EP) or Polydimethylsiloxane (PDMS) are blended into PC. The microscopic damage process and fracture surface is examined through the optical microscope and the scanning electron microscope. The EP and PDMS are found to improve the matrix / fiber interface strength since they may control crack propagation along the fiber. Tensile testing also shows that in modified PC the critical fiber length is quite shorter than the one in standard GFPC. Although the interface strength is improved, the fatigue lifetime of PC-PDMS is found to decrease because many crack tend to initiate and propagate around the fiber ends
Strain Rate Concentration and Dynamic Stress Concentration for Double-Edge-Notched Specimens Subjected to High-Speed Tensile Loads
Get PDFEngineering plastics provide superior performance to ordinary plastics for wide range of the use. For polymer materials, dynamic stress and strain rate may be major factors to be considered when the strength is evaluated. Recently, high speed tensile test is being recognized as a standard testing method to confirm the strength under dynamic loads. In this study, therefore, high speed tensile test is analyzed by the finite element method; then, the maximum dynamic stress and strain rate are discussed with varying the tensile speed and maximum forced displacement. The maximum strain rate increases with increasing the tensile speed u/t but the strain rate concentration factor Ktέ(t) = έyA(t)/έynom(t) is found to be constant independent of tensile speed, which is defined as the maximum strain rate έyA,max appearing at the notch root over the average nominal strain rate at the minimum section έynom(t). It is found that the strain rate at the notch root έyA,max depends on the dynamic stress rate at the notch root σ yA,max and independent of the notch root radius ρ. It is found that the difference between the static and dynamic maximum stress concentration (σyA,max − σyA,st) at the notch root is proportional to the tensile speed when u/t ≤ 5000mm/s. Strain rate concentration factors are also discussed with varying the notch depth and specimen length
Highly sensitive nuclease assay based on chemically-modified DNA or RNA
Get PDFNucleolytic enzymes are associated with various diseases, and several methods have been developed for their detection. DNase expression is modulated in such diseases as acute myocardial infarction, transient myocardial ischemia, oral cancer, stomach cancer, and malignant lymphoma, and DNase I is used in cystic fibroma therapy. RNase is used to treat mesothelial cancer because of its antiproliferative, cytotoxic, and antineoplastic activities. Angiogenin, an angiogenic factor, is a member of the RNase A family. Angiogenin inhibitors are being developed as anticancer drugs. In this review, we describe fluorometric and electrochemical techniques for detecting DNase and RNase in disease. Oligonucleotides having fluorescence resonance energy transfer (FRET)-causing chromophores are non-fluorescent by themselves, yet become fluorescent upon cleavage by DNase or RNase. These oligonucleotides serve as a powerful tool to detect activities of these enzymes and provide a basis for drug discovery. In electrochemical techniques, ferrocenyl oligonucleotides with or without a ribonucleoside unit are used for the detection of RNase or DNase. This technique has been used to monitor blood or serum samples in several diseases associated with DNase and RNase and is unaffected by interferents in these sample types