Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第15338号 / 工博第3217号 / 新制||工||1484(附属図書館) / 27816 / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 石田 毅, 教授 松岡 俊文, 教授 三ケ田 均 / 学位規則第4条第1項該当

This master’s thesis is concerned analysis of signal of acoustic emission. The analysis is based on data of bearing material and real bearings testing, tested in the Axmat stands. The data was run by software Matlab and Python. Below I created plan for identification of damage stage depending on particular AE events. The results are put into diagram. Finally I’m trying to develop the new possibilities of using acoustic emission into practice on the real machines. There could be earlier prediction of a defect of monitored bearings compared to vibrating diagnostic used until now.

<p>Two longstanding goals in subsurface science are to induce fractures with a desired geometry to adaptively control the interstitial geometry of existing fractures in response to changing subsurface conditions. Many energy and water-related engineering applications that use induced fractures to withdraw and inject fluids from subsurface reservoirs occur in some sedimentary rock.  Sedimentary rock such as shales often exhibit anisotropic mechanical properties because of bedding, layering and mineral texture.  These structural and textural features also affect fracture formation and in turn the resulting fracture geometry. Understanding the interplay between the microscopic mineral fabric and structure and how it effects fracture geometry is important for the prediction of the geometry of induced fractures and to the determination of the most ideal conditions for maximizing energy production and minimizing leaks from sequestration sites in the subsurface. </p> <p><br></p> <p>This Ph.D. thesis research focuses on the formation and geometry of fractures in anisotropic rock and the identification of geophysical signatures of fracture formation using additively manufactured gypsum rock analogs. Specifically, the work is grouped into three topics: (1) material controls on fracture geometry, toughness and roughness in additively manufactured rocks; (2) acoustic emissions (AE) during fracture formation in anisotropic additively manufactured rocks; and (3) determination of the effect of fluid-filled oriented voids in fractures on compressional to shear wave conversions. </p> <p><br></p> <p>For topic (1), unconfined compressive strength (UCS), Brazilian and 3-point bending (3PB) tests under pure and mixed mode mechanical tests were performed on cast and 3D printed gypsum samples that were characterized using 3D Xray microscopy, Xray Diffraction and SEM to examine the micro-structure of the samples. Research on topic 1 discovered microstructural controls on fracture surface roughness and the failure behavior of anisotropic rock and that the failure mode (tensile, mixed mode I and II, mixed mode I and III) affects the fracture propagation path and the surface roughness which is controls to the flow paths through a fracture. The results suggest that detailed mineralogical studies of mineral texture/fabric in laboratory or core samples is important to unravel failure strength, surface roughness, and how fractures propagate in layered geological media. </p> <p><br></p> <p>For topic (2), UCS tests were performed with concurrent measurements of acoustic emissions (AE) on cylindrical specimens: cast gypsum (CG) samples, and 3D printed (3DP) samples with five different orientations of bassanite layer and gypsum texture relative to the loading direction. Mechanical properties and induced fracture surface information were compared with the collected the AE signals to study if there is a way to tell the differences between the induced fracture surfaces with the AE signals patterns together with loading data. Examination of the AE signal amplitude from post-peak loading revealed that more ductile behavior was associated with more AE events that occurred over a longer period of time, and the resultant fracture surfaces were rougher than for narrow time distributions of events. </p> <p><br></p> <p>For topic (3), a detail study of fracture void orientation was performed using ultrasonic compressional, P, and shear, S, waves to determine how energy is partitioned when P-to-S or S-to-P conversions occur for waves normally incident on an air-filled or fluid-filled fracture. In this study, experiments and computer simulations were performed to demonstrate the link among cross-coupling stiffness, micro-crack orientation and energy partitioning into P, S, and P-S/S-P wave. The cross-coupling stiffness was created by 3D printing samples with linear arrays of micro-cracks oriented at  $0^o$, $\pm15^o$, $\pm30^o$, $\pm45^o$, $\pm60^o$, $\pm75^o$, and $90^o$. For $45^o$ orientation, measurements were made on air-filled and fluid-filled (silicon oil). For the air-filled fractures, the observed energy partitioning matched the simulated behavior obtained from discontinuous Galerkin simulations. Information on local fracture geometry is contained in the far-field waves. When filled with a viscous fluid, the P- and S- waves amplitude exhibited slight increases and decreases, respectively. The P-to-S converted mode amplitude decreased 30\% with an increase in fluid viscosity from 1–300kcSt. This suggests that P-S converted mode provides a potential method to remotely probe changes in fluid viscosity in fractures. </p> <p><br></p> <p>The work from the 3 research topics demonstrated that micro-scale structure impacts macroscale behavior and signals used for monitoring the condition of a rock. Additively manufactured samples enabled the exploration and determination of (1) the impact of mineral fabric orientation in layered media on failure load, fracture propagation path, and fracture surface roughness, (2) the sensitivity of P-to-S conversions to fluid viscosity, and (3) how oriented voids within a fracture effect energy partitioning. These research findings advances our current understanding of role microscopic properties and structure on the generation, propagation and geometry of induced fractures in anisotropic rock, and help to identify the best imaging modalities to use to identify the seismic signatures of the viscosity of fluids in fractures with oriented voids. These contributions will help unravel the complex behavior often observed in natural rock that is structurally and compositionally complex with features and heterogeneity.  </p> <p><br></p>

No description available.

<p>Electrical discharge machining (EDM) is a non-conventional machining process utilizing a series of electrical discharges to melt and vaporize workpiece material. In a wire EDM configuration wire breakage is a limiting factor in the machining productivity during the machining of workpieces with varying heights. Present methods of estimating workpiece height on-line in an effort to optimize machining parameters monitor the electrical signals for changes which may not be completely indicative of a change in workpiece height. This thesis intends to utilize acoustic emission (AE) sensors as a method for mapping the discharge location in order to estimate the workpiece height. This represents a novel approach as acoustic emission testing, while prevalent in the process monitoring of numerous conventional machining processes has yet to be significantly studied in combination with EDM.</p> <p>Another useful application of AE sensors with the EDM process under consideration is during the fast hole EDM process, where excessive wear is seen in the electrode causing true electrode length to remain uncertain. By using acoustic emission sensors to determine the true length of the electrode it could be possible to aid in the breakout detection of the electrode.</p> / Master of Applied Science (MASc)

Solanum lycocarpum é uma espécie brasileira conhecida por sua diversidade em glicoalcalóides (GA). Os GA solasonina (SS) e solamargina (SM), extraídos dos frutos desta planta, apresentaram propriedades antioxidantes e anticancerígenas atuando em diferentes mecanismos moleculares para a terapia do câncer. No entanto, a baixa solubilidade em água destas moléculas e a sua toxicidade limita a aplicação destes glicoalcalóides. Desta forma, o desenvolvimento de uma formulação nanoestruturada contendo GA pode possibilitar a sua aplicação clínica na terapia do câncer de bexiga (CB). Assim, este projeto visa o desenvolvimento e caracterização de carreadores lipídicos nanoestruturados (CLN) como sistemas de carreamento do extrato alcaloídico de S. Lycocarpum (EA), rico em GA, e avaliação da citotoxidade in vitro em células de câncer de bexiga. Os CLN foram preparadas pelo método de emulsão à quente e sonicação e otimizados utilizando um planejamento fatorial 23. No planejamento avaliou-se a influência de três variáveis independentes: tipo e quantidade de lipídio e tipo de surfactante nos fatores de resposta diâmetro e índice de polidispersão (PdI). CLNs foram caracterizadas de acordo com diâmetro médio, distribuição de tamanho e potencial zeta por espalhamento dinâmico de luz (DLS), índice de recristalização (IR) por calorimetria exploratória diferencial (DSC), porcentagem da eficiência de encapsulamento (EE%) por LC-MS/MS, avaliação morfológica por microscopia de força atômica (AFM), distribuição e concentração de nanopartículas por análise de rastreamento de nanopartículas (NTA), perfil de liberação do EA encapsulado em CLN pelo ensaio de perfil de liberação in vitro em células de Franz, e estabilidade ao longo do tempo. A citotoxidade dos glicoalcalóides foi avaliada pelo ensaio de captura do corante de vermelho neutro utilizando células de câncer de bexiga (RT4). As células foram tratadas com EA livre e encapsulado no CLN nas concentrações de 5 ?g/mL à 20 ?g/mL, assim como CLN vazia no período de 24h e 48h e foram calculadas suas respectivas concentrações inibitórias médias (IC50). O CLN desenvolvido apresentou tamanho inferior a 80 nm e potencial zeta negativo. O PdI foi inferior a 0,2 indicando uma baixa polidispersão. O CLN foi estável por 60 dias em relação ao tamanho, PdI e potencial zeta. O índice de recristalização (IR) do CLN com EA foi 47,23%, indicando uma estrutura menos cristalina do lipídio no CLN que propicia uma alta eficiência de encapsulamento de SS (86%) e SM (89,1%) e evita a expulsão dos ativos durante a estocagem. Os CLNs apresentaram-se semiesféricas como observado por AFM. A concentração de partículas, medida por NTA, foi de 9,74x 1011 partículas/mL e o diâmetro médio foi de 125 nm. Os glicoalcalóides presentes no EA encapsulado em CLN apresentam perfil de liberação in vitro sustentado após 36 h de liberação em condição \"sink\". O mecanismo de liberação dos GA foram diferentes, sendo que para o SS foi não-fickano enquanto que o SM foi fickano. O EA livre e encapsulado (CLN-EA) foi citotóxico frente células RT4, sendo que o CLN-EA foi mais citotóxico que o EA livre após 48h de tratamento. O IC50 das CLN-EA, após 24h de tratamento, foi de 15,94 ?g.mL-1 e 12,35 ?g.mL-1 após 48 h de tratamento. Esta redução no valor do IC50 está relacionada ao perfil de liberação dos glicoalcalóides SS e SM das nanopartículas. Os resultados demonstraram que a CLN desenvolvida é um sistema interessante para encapsular EA com potencial para futura terapia do câncer de bexiga / Solanum lycocarpum is a native species of the Brazilian savannah known for its diversity in glycoalkaloids (GA). The GA solasonine (SS) and solamargine (SM), extracted from the fruits of their plant, have antioxidant and antitumoral activity; acting on different molecular mechanisms interesting for cancer therapy. However, the low water solubility of these molecules and their toxicity limits their application. Thus, the development of a nanostructured formulation containing these glycoalkaloids may allow their clinical application in bladder cancer therapy (BC). Thus, this project aims at the development and characterization of nanostructured solid lipid (NLC) as carrier systems of alkaloidic extract of S. lycocarpum (AE), rich in GA, and their cytotoxic evaluation in order to obtain a nanostructured system for future intravesical therapy of bladder cancer. The NLC were prepared by the emulsion and sonication method and optimized using a factorial design 23. The influence of three independent variables was evaluated as type and amount of lipid and type of surfactant in response factors diameter and polydispersity index (PdI). NLCs were characterized according to average diameter, size distribution and zeta potential by dynamic light scattering (DLS), recrystallization index (RI) by differential scanning calorimetry (DSC), percentage of encapsulation efficiency (EE%) by LC MS/MS, morphological analysis by atomic force microscopy (AFM), distribution and concentration of nanoparticles by nanoparticle tracking analysis (NTA), the in vitro release profile of GA from NLC was done by Franz\'s cells diffusion, and stability over time by DLS. Cytotoxicity assay was evaluated by neutral red uptake assay in bladder cancer cells (RT4). Cells were treated with different concentrations of GA free and encapsulated in NLC (5-40 ?g/mL) and empty NLC for 24h, 48h and 72h. The NLC developed showed diameter smaller than 80 nm and zeta potential of -9.26 mV. The PdI was less than 0.2 indicating dispersion with low polydispersity. The NLC was stable for 60 days regarding to size, PdI and zeta potential. Recrystallization index (RI) of NLC-AE was 47.23%, indicating a less crystalline structure of the lipid in the particle, which provides high encapsulation efficiency of SS (86%) and SM (89.1%). This low RI prevents the expulsion of GA from NLC during the storage. NLCs exhibited semi-spherical form as observed by AFM. The particles concentration, measured by NTA, was 9.74 x 1011 particles/mL and the diameter was about 125 nm. The GA present in NLC-AE showed an in vitro sustained release profile after 36 h of release in a sink condition. The release mechanisms of SS and SM were different. The release mechanism of SS was non-Fickan while SM was Fickan. The AE free and NLC-AE was cytotoxic to RT4 cells, and the NLC-AE was more cytotoxic than the AE free after 48 hours of treatment. The IC50 of NLC-AE, after 24 hours of treatment, was 15.94 ?g.mL-1 and 12.35 ?g.mL-1 after 48 h of treatment. This reduction in IC50 value can be related to the release profile of the GA (SS and SM) of the nanoparticles. The results demonstrate that NLC developed is an interesting system to encapsulate AE with potential for future therapy of bladder cancer

As the introduction of semiconductor¡Bcomputer¡Bnetwork communcation¡Bmulti-media technology¡K¡Ketc. and the development and application of relevant automotive electronics, the car has becoming a high technological product instead of a traditional and machnical conveyance. Based on IC Insights, over 40% of vehicles will be equipped with automotive electronics and the automotive electronics market will reach the scale of US$192 billion in 2010. The scale of market is expected to reach the record of US$400 billion that represented over 50% of vehicles will be equiped with automotive electronics in 2015. The automotive electronics was divided to six functional field including ¡§Powertrain¡¨¡B¡¨Body¡¨¡B¡¨Chassis¡BSecurity¡¨¡B¡¨Safety¡¨ and ¡§Driver information¡¨. According to the research of IEK, ¡§Tire Pressure Monitoring System¡¨ is the most potential product in ¡§Safety¡¨ field for Taiwan manufacturers of IT industry to invest their resource. Based on Strategy Analytics, the global market of Tire Pressure Monitoring System reaches the scale of US$200 million in 2004 and the growth is expected to reach the record of US$1,279 million in 2008 and 63.6% annual compound growth. Quality Function Deployment (QFD) is a systematical tool with customer orientated concept. Adopting QFD method to product design efficiently is able to shorten development time¡Breduce cost and improve quality to satisfy customer¡¦s needs in his or her mind. This research is completed by case study of Tire Pressure Monitoring System (TPMS) which is developed by certain Taiwan company with potentials that is chosen by specialists. In this research we try to collect related information about certain company and explore customer¡¦s real-life needs by conducting questionnaire surveys. Kano¡¦s two-dimensional quality model is applied to identify customer¡¦s critical quality requirements. Quality factor¡Bsub-system/component and process are deployed by the matrix method of QFD to recognize key items for improving product design.

Many dynamical systems in nature and technology involve delays in the interaction of variables forming the system. Furthermore, many of such systems involve external inputs or perturbations which might force the system to have arbitrary initial function. The conventional way to model these systems is using delay differential equations (DDE). However, DDEs with arbitrary initial functions has serious problems for finding analytical and computational solutions. This fact is a strong motivation for considering abstractions and approximations for dynamical systems involving delay. In this thesis, the piecewise linear systems with delay on piecewise constant part which is a useful subclass of hybrid dynamical systems is studied. We introduced various representations of these systems and studied the state transition conditions. We showed that there exists fixed point and periodic stable solutions. We modelled the genomic regulation of fission yeast cell cycle. We discussed various potential uses including approximating the DDEs and finally we concluded.

Hundreds of thousands of landslides occur every year around the world impacting on people's lives. Monitoring techniques able to foresee imminent collapse and provide a warning in time useful for action to be taken are essential for risk reduction and disaster prevention. Acoustic emission (AE) is generated in soil and rock materials by rearrangement of particles during displacement or increasing damage in the microstructure preceding a collapse; therefore AE is appropriate for estimation of slope deformation. To overcome the high attenuation that characterise geological materials and thus to be able to monitor AE activity, a system called Slope ALARMS that makes use of a waveguide to transmit AE waves from a deforming zone to a piezoelectric transducer was developed. The system quantifies acoustic activity as Ring Down Count (RDC) rates. In soil applications RDC rates have been correlated with the rate of deformation, however, the application to rock slopes poses new challenges over the significance of the measured AE trends, requiring new interpretation strategies. In order to develop new approaches to interpret acoustic emission rates measured within rock slopes, the system was installed at two trial sites in Italy and Austria. RDC rates from these sites, which have been measured over 6 and 2.5 years respectively, are analysed and clear and recurring trends were identified. The comparison of AE trends with response from a series of traditional instruments available at the sites allowed correlation with changes in external slope loading and internal stress changes. AE signatures from the limestone slope at the Italian site have been identified as generated in response to variations in the groundwater level and snow loading. At the conglomerate slope in Austria, AE signatures include the detachment of small boulders from the slope surface caused by the succession of freeze-thaw cycles during winter time. Consideration was also given to laboratory testing of specific system elements and field experiments. A framework towards strategies to interpret measured acoustic emission trends is provided for the use of the system within rock slopes.

Augmented Reality for smartphones, while still in its initial stages, has a great potential in relation to the future path of mobile marketing and has already shown significant market presence thus far. However, Augmented Reality is an almost new concept, but its basis and techniques have been used for years. By generating enthusiasm in the retail market, Augmented Reality presents many opportunities. Simulating virtual interaction in real-time for an unknown product, encourages customers to experience an advertisement. The sense enhancement that Augmented Reality provides over a real-world environment, might be either the result of the device's location or the environmental images surrounding the device. The latter is called vision Augmented Reality. This study aims to develop a vision-based Augmented Reality application for Android platforms. The idea is based on a proposal offered by a ProductPackaging company, which would like to develop a smartphone application in order to provide shoppers an idea regarding what is inside the package. However, this is only one of the numerous advantages that AR brings and the benefits of this technology appears to be almost limitless in relation toincreasing productivity for customers. Once the goal has been achieved, the application can be used to provide relevant information about the product suchas physical specification, ingredients, animated instruction manual, repair wizard and so on. The main focus of the entire implementation is on integrating an existing ARSDK and a Java rendering library so that they can cooperate together. In addition, the fundamentals associated with the Image Registration process, which is the basis of Augmented Reality, are addressed. Both the advantages and drawbacks of the implementation model are discussed in this paper as arethe problematic issues surrounding the execution steps.