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Development of Floating Type Ocean Wave Power Station
No full text九州工業大学博士学位論文 学位記番号:工博甲第378号 学位授与年月日:平成27年3月25日第1章 序論||第2章 浮遊式波浪発電ステーションの着想||第3章 プラットフォームの挙動||第4章 ランナケーシングの影響||第5章 タンデムランナの性能||第6章 結
Development of Counter-Rotating Type Tidal Stream Power Unit
No full text九州工業大学博士学位論文 学位記番号:工博甲第377号 学位授与年月日:平成27年3月25日第1章 序論||第2章 相反転方式潮流発電ユニットの着想||第3章 相反転方式潮流発電ユニットの基本特性||第4章 パイル式による設置||第5章 新たな係留方式による設置||第6章 潮流発電用タンデムプロペラの高効率化||第7章 相反転方式潮流発電ユニットの構築||第8章 結
多様な生物学的データを複雑な代謝ネットワークに統合するための補完的エレメンタリーモード解析法の開発
No full text九州工業大学博士学位論文 学位記番号:情工博甲第299号 学位授与年月日:平成27年3月25日1 Introduction||2 Background||3 Materials and Methods||4 Results and Discussions||5 Conclusion, Scope and Future Research InterestSystems biotechnology is an approach to develop comprehensive and ultimately predictive models of how components of a biological system reproduce its observed behavior.
The major human diseases like as diabetes, obesity, high blood pressure, cardiovascular disease and cancer are involved in failure of human metabolic systems. Therefore, metabolism is an important biological process, but these are complex and highly interconnected each others. Metabolic network maps are represented by a complex chain of chemical reactions and are highly associated between genes, proteins and enzymes; consequently mathematical and/or computational approaches are necessary for integration of them. Heterogeneous biological data, including genome, transcriptome, proteome, and metabolome are integrated into a pathway-based metabolic model to predict a flux distribution of genetically modified cells under particular conditions. The integration of heterogeneous biological data and model building have become essential activities in biological research as technological advancements continue to empower the measurement of biological data of increasing diversity and scale. But the challenge becomes how to integrate this data to maximize the amount of useful biological information that can be extracted.
Metabolic pathway analysis is theoretically effective in integrating heterogeneous biological data into metabolic network and to offer great opportunities for studying functional and structural properties of metabolic pathways. Metabolic pathway analysis has focused on two approaches, namely, elementary modes (EMs) and extreme pathways (Expas). EM analysis is potentially effective in integrating transcriptome or proteome data into metabolic network analyses and a minimal set of reactions that can maintain the steady state level, while Expa analysis is a subset of EM that contains two additional conditions and one of them condition to make all Expas systematically independent. The EM coefficients (EMCs) indicate the quantitative contribution of their associated EMs and that can be estimated by maximizing as a particular objective function. A serious problem of EM/ Expa analysis is that the computational time increases exponentially with an increase in network sizes, which makes the computation of the all EMs/Expas expensive and impracticable for large- or genome-scale networks. Another major problem is that many organisms still does not have provide any specific objective biological function for estimating the EMCs to predict the flux distribution relate to the optimum physiological states and EMs can be described by different scalar products or many possible vectors of each EM, but the predicted flux distributions must be independent of them.
To address such aforementioned problems, in this thesis we present a fast and efficient algorithm, called complementary EM (cEM) analysis, to reduce the number of EMs/Expas. To achieve the computational time improvement, we employ the EM decomposition method that explores major EMs or linear combinations of them which are responsible for the metabolic flux distributions. Flux balance analysis (FBA) is used to generate many possible ranges of metabolic flux distributions as the input data, which is necessary for the EM decomposition method. The maximum entropy principle (MEP) is used as an objective function for estimating the coefficients of cEMs, to renounce the scalar product problem of EMs. MEP is widely used for flux prediction in particular cases where no biological objective function is available and most advantages that it does not depend on the scalar product of each EM.
To demonstrate the feasibility of cEM analysis, we compared it with EM/Expa analysis by using a simulation study with an artificial metabolic network model and real metabolic network analysis by two medium-scale metabolic network model of E. coli and a genome scale model for head and neck cancer cells. The cEM analysis greatly reduces the number of EM, computational time and memory cost for the genome-scale metabolic network. Application of cEM analysis to Genetic Modification of Flux (GMF) accurately predicts the flux distributions of genetic mutants under particular conditions. Use of cEMs analysis, to plans a genetic engineering strategy for genome-scale metabolic network model for producing useful compounds.
Keywords: Systems biotechnology; Integrating biological data; Constraint-based metabolic modeling; Large-scale metabolic network; Elementary mode decomposition; Complementary elementary mode analysis; Quantitative contributions; Prediction speed and accuracy
CMPにおける可変回転ポリシング法に関する研究
No full text九州工業大学博士学位論文 学位記番号:情工博甲第301号 学位授与年月日:平成27年3月25日CHAPTER 1 Introduction||CHAPTER 2 The Chemical Mechanical Polishing Technology||CHAPTER 3 The Variable Rotation Polishing Method in the
CMP Process||CHAPTER 4 The Polishing Performance of Variable Rotation Polishing Method||CHAPTER 5 Mechanisms Analysis of the Variable Rotation Polishing Method||CHAPTER 6 Polishing Pad Analysis by 3D Topography Observation||CHAPTER 7 ConclusionsVariable rotation polishing (VRP) method is proposed in order to improve polishing performance such as material removal rate (MRR). The VRP method is characterized as a combination of the additional backward rotation with the forward rotation only (i.e. the conventional polishing). The MRR increases as the angle of additional backward rotation becomes higher until 360 degrees. In that case, the MRR of the VRP method was 38 percent higher than that of the conventional polishing.
Asperity of polishing pad surface is one of the dominant parameters affecting the MRRs and stabilities of the Chemical Mechanical Polishing (CMP) process. According to the investigation of a polishing pad surface topography suggests that the asperity of the polishing pad surface was kept standing upright by backward rotation of the polishing pad. Particularly, the peak area of the asperities on polishing pad surface, the roughness became higher in the VRP method than in the conventional method. This result predicts that there are more the number and the area of the polishing pad asperities, which would approach near to the wafer surface being polished, are kept standing upright in the VRP method. Therefore, these asperities was able to consequently sustain the MRRs. In other words, this behavior suggests that in the VRP method, the preservation of the asperity on polishing pad surface would sustain the MRR because of the backward rotation, which may contribute to the realization of a polishing pad conditioning treatment-free CMP process. This feature also indicates that this method could result in the longer polishing pad life, namely the cost reduction of polishing pad.
Slurry flow distribution and slurry film thickness were also evaluated in the VRP method comparing to the conventional polishing method. The slurry flow distribution was analyzed through a transparent quartz substrate by a high-speed camera. The slurry flow distribution of the VRP method was not uniform as compared with the conventional method, although the MRR of the VRP method was higher than that of the conventional method. The slurry film thickness variation was measured using a surface scanning laser confocal displacement meter on the upper surface position of a quartz substrate with and without slurry. The position of a quartz substrate varied from 9 μm to 8 μm during the CMP process. This implies that the slurry film thickness in the VRP method was 1 μm thinner than that of the conventional polishing. These results suggest that these 2 parameters are not dominantly effective against the MRR of the CMP process.
As above mentioned, the preservation of the asperity on polishing pad surface is one of the dominant parameters to sustain the MRR
鋼製軸と焼嵌接合された加熱炉用セラミックローラーにおける接合部の強度と軸の抜け外れに関する研究
Get PDF九州工業大学博士学位論文（要旨） 学位記番号：工博甲第393号 学位授与年月日：平成27年9月25
Fatigue Strength for Bolts and Nuts Having Slight Pitch Difference Considering Incomplete Threads of Nut
Get PDFThe high strength bolts and nuts are widely used in engineering structures. To investigate the pitch difference on the fatigue strength of bolt, a slight pitch difference is considered between the bolt and nut. Here, the pitch of the nut is α μm larger than the pitch of the bolt. The fatigue experiment is conducted with varying pitch difference. The results show that the fatigue life is extended to about 1.5 times of the one of normal bolt and nut by introducing the suitable pitch difference under the high stress amplitude. According to the detailed observation on the fractured specimens, it is found that the fractured positions and the crack distributions vary depending on the pitch difference. To clarify the improvement mechanism of the fatigue strength, the finite element method is applied to calculate the stress amplitude and mean stress at each bottom of bolt threads. It is found that the finite element analytical model considering the incomplete nut threads is useful for predicting the crack initiation under different pitch difference introduced
