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Construction of Multi Viewpoints Database by GA for AR
Get PDFThe 3rd International Conference on Industrial Application Engineering 2015, March 28-31, 2015, Kitakyushu International Conference Center, Kitakyushu, JapanRecently, as a useful application, the Augmented Reality (AR) has been widely adopted in mobile devices. In order to make the AR working smoothly on a low calculation ability smartphone, the high robustness and low calculation cost method is required. To realize such requirements, the Representative Image (RI) has been proposed. But, it does not guarantee the robustness in every case. In this study, an improved RI method using genetic algorithm is proposed. The numerous simulation result shows the proposed method is more robustness than the traditional one
3D Numerical Simulation of Epidermal Skin Turnover Process Using a Particle Model
Get PDFSkin is the largest organ of the human body. In recent years, concern regarding the cosmetics area has increased, and research studies on anti-aging therapy or cosmetics have been rapidly conducted. Skin cells are not only changing its shape but also its physical properties during the epidermal skin turnover process. Computational simulation can be useful in further understanding the mechanisms of skin formation. We propose a particle model that can handle complex biological phenomena, including cell interactions and is a suitable method for simulating skin formation. The particle model was applied to simulate three-dimensional skin formation accompanied by proliferation and cornification of skin cells. The simulation results represented and reproduced the epidermal skin turnover phenomenon
Investigation on coming out phenomenon of the shaft from the sleeve by 2-D plate model approach
Get PDFThe ceramics roller can to be used in the heating furnace because of high temperature resistance.
The roller consists of ceramics sleeve and steel shaft connected by shrink fitting. Since ceramics is brittle, it should be noted that only low shrink fitting ratio can be applied for the connection. Therefore, coming out of the shaft from the sleeve during rotation should be investigated in this study. In this study, the finite element analysis is applied to simulate this phenomenon. In the previous study, mechanism of coming out has been considered by using 3-D model. However, since 3-D model analysis needs large computational time, only small number of cycle can be considered, and therefore, the coming out phenomenon cannot be predicted easily. In this research, the 2-D plate model approach is proposed in order to reduce computational time, considering the upper and lower alternate load, repeatedly. Then, the effects of the magnitude of the load and shrink fitting ratio are investigated systematically. Finally, the simulation of the coming out phenomenon can be carried out for much larger number of cycles
Several solutions of intensity of singular stress useful for evaluating bonded strength
Get PDFProceedings of 4th International Conference on Fracture Fatigue and Wear, FFW 2015, Ghent University, Belgium, 27-28 August 2015Adhesive joints are widely used in many industrial sectors since the numerous advantages over other traditional joints. However the mismatch of different materials may cause debonding of the joints. Since few studies are available for evaluating the bonded strength, this study will focuses on the solutions for the intensity of the singular stress for several typical adhesive joints, such as bonded plate and butt joint in plane stress state, bonded cylinder/pipe under axial-symmetric state. In this research, an effective numerical method combined with FEM results is used to obtain the SIFs at corner of adhesive joints in arbitrary material combinations. Here the simple bonded plate, which has already been solved accurately in our previous study, is used as the reference problem. We will discuss the effect of the adhesive thickness in a butt joint, and defined a new parameter for semi-infinite structure; and for the bonded joints in axial-symmetric, the nonsingular terms are derived so that the SIFs can be obtained, and it is found that the axial-symmetric problem are quite different since the SIFs cannot be dominated by the Dunders’ parameters. And at last, the SIFs for several problems are discussed and compared with each other
Guide for the Online Publication of the Doctoral Thesis
Get PDF平成27年度博士論文インターネット公表の基礎知識説明会, 日時・場所：平成27年6月26日（金）九州工業大学情報工学部分館,7月2日（木）九州工業大学附属図書館,7月17日（金）九州工業大学若松キャンパス講義室
On the Nonlinear Stabilization Problem via Quadratic Immersion Part II: A QI-based approach for the design of nonlinear regulators having exponential-tunable performance
No full textThe results of Part I of the paper are here exploited in order to define a regulator design method for Sigma/Pi-systems, even non stationary, which makes use of a static state-feedback working in the same domain as the open-loop system. Sufficient conditions are given in order that a fixed performance, in terms of convergence rate, be achievable. Provided these conditions are satisfied the regulator steers the system state to zero, at an exponential, tunable, rate and the domain of 'attraction' of the zero will include all points from which the orbits of the closed-loop system are bounded. For stationary systems additional results are proven as far as the accessibility property
Controls of Thermal Properties by Using Self-Assembly
No full text九州工業大学博士学位論文 学位記番号:工博甲第375号 学位授与年月日:平成27年3月25日第1章序論||第2章自己組織化による微細構造作製手法||第3章自己組織化微細構造による熱伝導特性制御||第4章自己組織化微細構造による熱ふく射特性制御||第5章結
キャンパスWAMSによる改良されたヒルベルトホーン変換を用いた電力系統動揺特性解析
Get PDF九州工業大学博士学位論文 学位記番号:工博甲第390号 学位授与年月日:平成27年3月25日Chapter1. Introduction||Chapter2. Wide-Area Measurement System Using Synchrophasors Technology||Chapter3. On-line Oscillation Characteristics Monitoring Algorithm Analysis||Chapter4. The Enhanced HHT Method||Chapter5. The Developed Oscillation Monitoring System||Chapter6. ConclusionsThis dissertation presents a complete oscillation monitoring system based on real-time wide-area measurements from PMUs. This oscillation monitoring system employs the enhanced Hilbert-Huang transform (HHT) to analyze power system oscillation characteristics and estimate the damping of oscillatory modes from ambient data. This new oscillation system can give an indication of the damping of transient oscillations that will follow a disturbance, once it occurs. The application is based on a system identification procedure that is carried out in real-time.
This research studies various low frequency oscillation analysis algorithms. It mainly introduces the concept, character and implementation process of FFT, WLT and HHT method. According to the characteristics of low frequency oscillation signal we can get advantage and disadvantage of these algorithms.
It is important to remember that power system is actually a high-order time-varying nonlinear system. Only under certain circumstances can it be simplified to linear or time-invariant systems. Although ambient condition is reasonably molded as a linear system, for system response following some events, nonlinearities play an important role in the measured data. HHT is a new type of nonlinear and non-stationary signal processing method. Compared with other methods, HHT has absolute advantage of analyzing low frequency oscillation signal because the power system responses following system disturbances contain both linear and nonlinear phenomena.
Nevertheless, the traditional methods, whether FFT or WLT, etc. the signals are approximately processed as linear signal when analysis non-linear and non-stationary signals. This feature is the main advantage of HHT algorithm, which is also widely used by the reasons. Secondly, HHT method is adaptive, which means that can be adaptive extracted from the signal decomposed by EMD itself. It is based on an adaptive basis, and the frequency is defined through the Hilbert transform.
Consequently, the "base" of Fourier transform is the trigonometric functions, the "base" of wavelet transform requires pre-selected. Therefore, HHT has completely adaptability. Third, it is suitable for analysis mutation signal. Due to the Heisenberg uncertainty principle constraint, many traditional algorithms must be satisfied the product of frequency window by time window is constant. This property makes these algorithms cannot achieve high precision both in time domain and frequency domain at the same time. Nevertheless, there is no uncertainty principle limitation on time or frequency resolution from the convolution pairs based on a priori bases. For these reasons, it can be said applying HHT method to dealing with power system oscillation signal is a good choice. However, it is still have some issues need to be resolved carefully.
To ensure accurate monitoring of system dynamics with noise-polluted WAMS measurements, serval key signal-processing techniques are implemented to improve
HHT method in this research: Data pre-treatment processing, the boundary end effect problem caused by the Empirical mode decomposition(EMD) algorithm and the boundary end effect problem caused by Hilbert transform based on Auto-Regressive and Moving Average Model (ARMA). There are six methods: a). polynomial extension method, b). slope method extension method, c). parallel extension method, d). extreme point symmetric extension method, e). mirror method f). Boundary local characteristic scale extension methods are used to inhibit the boundary end effects, which results in a serious distortion in the EMD sifting process.
Furthermore, an integrated scheme for the monitoring and detection of low-frequency oscillations has been developed based on HHT algorithm for oscillation analysis in CampusWAMS projects. By analyzing the real-time synchro-phasors, the proposed scheme is competent to identify the characteristics of the low-frequency oscillations in real-time.
Third, this dissertation presents an estimation algorithm method based on enhanced HHT for the parameters of a low frequency oscillation signal in power system.
In the end, the developed scheme is tested with simulated signals and measurements from CampusWAMS. An oscillation monitoring system based on real-time wide-area measurements from PMUs is established. It can determine the center rage frequency of the concerned mode automatically and accurately, which is then be used to determine the parameter of the extraction. The extracted mode frequency, damping and mode shape can be detected by this oscillation monitoring system. The results have convincingly demonstrated the validity and practicability of the developed scheme