Due to changing social requirements, today's doctoral education must prepare students to be able to work in a broader spectrum and apply one's skills to a multidisciplinary setting while maintaining a high level of expertise. This paper outlines the development of an education program for Ph.D. students to cultivate literacy and competency, in addition to comprising a doctoral thesis and highlighting the ability to achieve results through innovative research. The program aims to cultivate fundamental attainment, specialized knowledge, literacy (language, information literacy, technological literacy, legal knowledge, and ethics), and competency (creativity, problem identification and solution, planning and execution, self-management, teamwork, leadership, a sense of responsibility and duty). In order to cultivate these abilities, simply attending lectures is insufficient, so we have to develop industry-university collaborative education programs.

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Recently, the renewable energy technology attracts global attention. Although, wind energy do not plays a central role of energy production in Japan. One of the strategy to keep the development of wind energy is student education about the wind turbine technology. However, to educate both theory and actual practice at the same time for student who have less technical skills is difficult in introductory education. In this study, we developed the experimental teaching material for college student, using horizontal axis wind turbine (HAWT) generator paper model, wind turbine calculation software (QBlade) and Arduino compatible system board. The teaching material provides the experience about a method of developing the optimal airfoil design of the wind turbine rotor blade with "assembling the original wind turbine paper model" and "fluid calculation of the rotor blade by GPL wind turbine calculation software". Furthermore, it provides the learning opportunity about a method of developing the simple data acquisition system by using Arduino compatible system board.

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Some young engineers and students who were educated after the development of computer technology are convinced that findings based on computer-aided engineering (CAE) are equally valid as those obtained in real life, because they have little experience of physical phenomenon. We consider the construction of "waribashi bridges" and "taketombos" as examples of PBL(problem-based learning) projects to correct the discrepancy between real-life experience and virtual experience. That they make a waribashi bridge and taketombo with a knife supplements their shortage of a physical experience, and making the taketombo from NC machine improves their knowledge. Through these projects, students recognized the usefulness of 3D-CAD(computer-aided design) and CAE for engineering design, the limits to the applicability of CAE, and the importance of observing actual phenomena.

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The phenomena with relation to fluid mechanics are often taken up in scientific books for popular readers. However, the explanation on principle of them has been described under misunderstood knowledge on fluid mechanics in many books. It seems the reason that the many authors are not understood fluid mechanics enough. Also, there is the further reasons in the descriptions involved mistaken explanations in many books. In present study the mechanism of transmission of so misunderstood explanations has been considered, and the diffusion of them has been investigated on principle on a spray. It is also examined and proposed how to prevent the transmission and diffusion of the misunderstood knowledge.

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The authors have analyzed and manufactured children's toys. They are paper boomerangs, boomerang planes, bamboomerangs, paper cup boomerangs and PET bottle rockets. They are not danger and can be manufactured by a child. The authors taught to children with toys about manufacturing and way of playing toys. The authors' purpose is that children are interested in manufacturing and understand why become so through our toys were analyzed and manufactured. The authors analyzed about paper flying ring in this time. The flying ring is toy that flied to far with throwing it. The authors can manufacture it from paper. There is a sold flying ring but it is expensive for children. Our flying ring is very cheap because it is manufacture from paper.

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Fifty years passed after College of Technology started and more than four hundred thousand students graduated. It is found from various statistics datum that children of people which are seriously affected by economic condition enter to College of Technology. Fifty years' history of College of Technology is introduced roughly. The roles of College of Technology are reconfirmed by using various statistics datum (Application rate to College of Technology, Promises of employment of students of High School, Junior College and College of Technology)

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The Great East Japan Earthquake occurred on March 11, 2011, and the earthquake disaster cut off gas, electricity and running water in areas of Tohoku region. In the area damaged by the disaster, residents are aiming at self-sufficiency in regards to energy use by renewable energy in public offices etc. In this background, we focus on a Stirling engine in which high-efficient power generation is theoretically possible in low temperature difference. Further we proposed a unique home co-generation system by the practical free piston Stirling engine that use wood pellet fuels. Students in our laboratory have challenged to experiment the performance test of the system. In this report, we introduce the mechanism of this system and the results of the basic performance tests. Finally, the practicability of the home co-generation system are reported. We tackled the engineering education of energy and environment using the constructed co-generation system with the practical Stirling engine. These processes are just the aim of engineering education.

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Early locomotives are reviewed from the standpoint of start of railroad axle rotation and fretting fatigue. Richard Trevithick, William Hedley, and George & Robert Stephenson were English engineers who made great works for steam locomotives. Meanwhile, John Stevens in the US was the pioneer for US steam locomotives. Richard Trevithick started to use rotational axles from the first stage in the locomotive era in 1804, and there were no fretting fatigue since he seemed to use a key ditch and a cotter. Fretting fatigue occurs at a contact surface in a condition of load and flexural movement. In that sense, the locomotive in 1814 made by William Hedley may be the first to have a possibility of fretting fatigue. One of the first axle failures can be admitted in a novel of memoire of a tourist by Standahl in 1838. This is considered to be one of the first failures by fretting fatigue.

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Consideration on the relation between the military technology and the non-military technology is performed by comparison between two flying boats. One is the flying boat type 2 of the Japanese Navy, which was used for fighting in the World War II. The other is the type US-1 of the Maritime Self-Defense Force of Japan, which has been used to rescue the people who meet with a disaster on sea. First, the flying boat type 2 is explained. By agreement of the disarmament conference in 1922, the former Japanese Navy determined to produce big flying boats to compensate the lack of the marine power. Kawanishi Aircraft Co. (next ShinMaywa Industries Ltd.) received the request from the navy and developed the flying boat type 2, which succeeded in the first flight in 1942. It had the maximum high performance as that time. Next, the rescue flying boat US-1 is explained. Although it was a new type of flying boat of which ShinMeiwa Industries Ltd. received an order from the Maritime Self-Defense Force, the base was the antisubmarine patrol flying boat PS-1, whose developers were the same as the developers of the type 2. Therefore, as for the origin of design technique, it is the type 2 and the appearance also resembles it. After describing that the rescue activity of the rescue flying boat is usually done with the (antisubmarine) patrol aircraft (PS-1, P2-J, P3-C, etc.), the meaning of classifying the technology into military one and non-military one is discussed. Finally, it is concluded that evaluation of the technology is "relative" and is done by not the engineer but the society and the citizens.

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The authors did the field survey of the oxcarts in the Turkish western coastal zone in 1998. Overviews of them were released at the annual meeting of 2007. However, it did not lead to the specification data of the oxcarts. In the present report, authors tried to clarify the dimensional data and structure about oxcart having two wheels which was exhibited to the Ephesus Museum in the Selcuk city. As a result, authors have made clear that the interval of the travelling wheel of the oxcart is almost same as 1,435 mm (4 ft. 8.5 in.) of the standard gauge of the railway in today.

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The Y-shaped lumbers of chestnut trees from the Jomon period about 4000 years ago were excavated at the Sakuramachi site in Oyabe City, Toyama, Japan in 1997. The usage of Y-shaped lumbers at this site has not yet been clarified. A field survey of the Y-shaped lumbers of the Sakuramachi site was performed and structural characteristics of the Y-shaped lumbers were investigated by the author Ozawa et al. According to structural characteristics, the hypothesis that they could have been used as sledges has been proposed. It is thought that the people from the Jomon period about 4000 years ago used the Y-shaped lumbers to transport heavy items such as giant trees. Giant chestnut trees were excavated at the sites of the Jomon period such as the Sakuramachi, the Mawaki, and the Chikamori sites and so on. The giant tree culture had been existed in the Hokuriku region on the Sea of Japan coast in the Jomon period. In this paper, the positioning of the Sakuramachi site in the giant tree culture of the Jomon period is discussed.

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In former factories, plural machines were operated on one power source. We have investigated this driving system in Tokai area and considered the characteristic. In the " Yamaya" brewing factory of Takahama-shi, Aichi, we report the example that squeezed soy sauce by plural compressors.

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For high temperature combustion for metal de-oxidation (reduction), air blower have to be used. Especially for iron making from iron ore, which melting temperature is very high to reach only self combustion of charcoal or coal. In antiquity days, man blower with pipe was used, after that, bellows type was developed, however these system was suitable only for small amount production. If society wants large amount of iron; for example in civil war age, these system cannot supply the amount. Therefore, new type of blower system which used water mill was developed. This report deals with the variation of this system in Japan; Kagoshima, Izumo and Tohoku area by point out the difference of surrounding society.

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The author has studied on Isambard Kingdom Brunei (1806-1859), British civil engineer, for twenty years. And, the author collected a lot of reference books on him and his times. The contents are divided into bibliography, works, fact list, guide book, related novel, and so on. In this manuscript, the author summarized and listed them on a database of FileMaker. Over 140 books were contained in the database, and labeled for author's name, book name, its subtitle, publisher, published year, page, chapter structure and title, and memorandum. In the manuscript, some of characteristic and typical books have been introduced their context with brief comments. The object of this study is to introduce Brunei's references for increasing the number of people who are interested into and study on Brunei and his spiritual engineering works.

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The surveying measured distance and was intended to get the area of the land. We wrote down the result and showed a state of the land to one piece of paper, and it became a map to convey as information. Every time the change of a reduced scale and the viewpoint to grasp a position and mutual relations is carried out, write the map of the paper; it is necessary to clear it, and serious cost produces it. I displayed an object on a display by the appearance of the computer and thought that convenience planned it by unifying various information, and being connected. This develops to today's GIS: Geographic Information System. The development of the computer lowers calculation cost and promotes the complex use, and this can say to the design of the machine. I want to mention a method to lower calculation cost.

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How much do we measure invisible value of scientific knowledge? We focus on joint research between company and academia as measurement of absorption of scientific knowledge. We picked up pharmaceutical company. We empirically approach to this topic by data on joint research between company and academia using database on academia-industry collaboration by Ministry of Education, Culture, Sports, Science and Technology. As a result, absorption of science knowledge does not affect patent applications. On the other hand, it affects efficiency of patent application. This implies that if a company is engaged in joint research with academia it need not conduct basic research that is uncertain and requires huge expenditure. Absorption of scientific knowledge does not affect new drug approval. This would indicate that scientific knowledge explicitly affects corporate performance of research indicated by efficiency of patent application but does not affect creation of new drug that requires huge cost for introduction to market (e.g. clinical trial).

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According to the case of Actemra that is the first antibody drug approved for sale in Japan, I picked up the factors for successful industry-academia collaboration for innovative drug development. First, passion and confidence of academic researcher and a relationship of mutual trust between academic researcher and industry counterpart encouraged the decision of investment for large-scale production in corporation. Second, as a basis of such decision, patent in the academic side had been obtained. Third, there were a researcher who understood both of basic research and clinical application. In order to increase the number of drugs developed using knowledge of academia, policy measure to establish such conditions are required.

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Information of the society brought on by the Internet is remarkable. Patent system was also the transformation by this information, but the world with increased amount of information, a thing called invention would go How is future. This is to report on the current status and future sprinkled with personal opinion "Intellectual Property Exchange International (IPXI)" from the "3D printer". I considered two with this "3D printer" "Intellectual Property Exchange International (IPXI)" in and contribute to the industry in the future. The invention will become familiar for the population of a few or more personal. I is believed to boost the growth of small amounts of various production industry in the future these. And think of the characteristics, and rather than a growth of only one country one, what they bring, will be growth and resulted in a synergistic effect in countries. There is a possibility of change of the patent system by this wave.

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The purpose of the Patents Act is, through promoting the protection and the utilization of inventions, to encourage inventions, and thereby to contribute to the development of industry. Thus, the provisions of the Patent Act affect the promotion of the future innovation. In late years, revisions of the Patent Act are serious issues. In this presentation, a new system about "Exceptions to Lack of Novelty of Invention" is described. Also, in comparison with the systems of many foreign countries, the practical issues for international patent applications are discussed. Moreover, in late years, Employee's Invention is also one of the serious issues. The new system of "Employee's Invention" was adopted by the revision of the Patent Act in 2004. In this presentation, the stipulations of "Employee's Invention" are compared with many foreign countries, and the future revisions of the stipulation of "Employee's Invention" are discussed.

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Computational fluid dynamics (CFD) analysis consists of three phases: 1) pre-processing, e.g., grid generation; 2) fluid analysis; and 3) post-processing, e.g., visualization. With the recent improvement in computer performance, pre-processing takes up a higher proportion of the total number of processes in extensive and complex CFD analyses. In this study, we developed a novel method for automatic generation of robust structured grids during the initial stage of fluid analysis to reduce the computational cost of grid generation. By implementing this method, we successfully reduced the computational cost of grid generation, and approximately thirty million grids were generated on the K computer within thirty minutes. By using these generated grids, over eighty percent weak scaling up to 4000 nodes on the K computer is obtained.

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Methodology is developed to reduce manual work in preparing geometry for simulation when working with dirty computer-aided-design data. A method that uses arbitrary boundary representation is proposed with a dummy-cell technique based on a Cartesian grid and immersed boundary method. The complicated geometry is degenerated into cell-oriented values. The advantage is that the user can handle data that have a gap, overlap or sharp edge without any special preprocessing. The force term of the immersed boundary method is directly imposed on an arbitrary ghost cell by linear interpolation of the velocity, which is defined according to the distance between the cell-centered position and the crossing point with the grid line. The intersection point is obtained from the face center and normal of the characteristic wall. A calculation example of a full vehicle model provided by an automotive company is presented, and robust flow field results are obtained.

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Large-eddy simulation (LES) has been applied to investigate the unsteady aerodynamics of road vehicles. Six degrees of freedom equations of vehicle's dynamic motion were installed in the unstructured finite volume LES code developed, and its motion was numerically reproduced by the coupling of the Arbitrary Lagrangian-Eulerian method and Navier-Stokes equations in non-inertial reference frame. The simulation code was implemented on a massively parallel processor to satisfy the demands of large-scale and long-term aerodynamic simulations of full-scale vehicles with complicated geometry.

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A Fluid-Structure interaction method has been developed for massively parallel computing. The method is suitable for the direct simulation from medical image data without a mesh generation procedure. The method employs the concept of Volume of Fluid approach for describing the motion of both fluid and solid. The method is further developed to describe the motion of membrane. The method is used to simulate the blood flow containing many red blood cells and platelets. Using this method, multiscale simulation of the initial stage of thrombosis is conducted with the coupling of Monte Carlo simulation for protein-protein (GPlba-vWF) binding.

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Large-scale detached eddy simulations (DES) have been conducted on the K computer, in order to elucidate the flow mechanism of the rotating stall inception in a multi-stage axial compressor for an actual gas turbine. The detached eddy simulation approach is based on k-ω two-equation turbulence model. The present DES program parallelized with MPI has high speed-up performance. To investigate complex vortical flow phenomena at near-stall conditions, vortex structures are identified by the critical point theory, and limiting streamlines are visualized by a line integral convolution (LIC).

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Coal is an important energy resource for future demand for electricity, as coal reserves are much more abundant than those of other fossil fuels. In pulverized coal fired power plants, it is very important to improve the combustion efficiency and the reduction of pollutants such as nitrogen oxide, sulfur oxide and ash particles. In order to achieve these requirements, understanding the pulverized coal combustion mechanism is necessary. However, the combustion process of the pulverized coal is not well clarified and physically modeled so far since pulverized coal combustion is so a complicated phenomenon that the maximum flame temperature exceeds 2000 ℃ and some substances which is difficult to be measured, for example, radical species and highly reactive solid particles are included. Accordingly, development of new combustion furnaces and burners requires high cost and takes a long period. In this study, a Large Eddy Simulation is applied to a pulverized coal combustion field.

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The effect of ambient pressure on turbulent spray combustion behavior is investigated by means of Large-Eddy Simulation (LES). The ambient pressure is set to 0.1, 0.5 or 1.0 MPa. Jet-A is used as a liquid fuel. The evaporating droplets' motions are tracked by a Lagrangian method with non-equilibrium Langmuir-Knudsen evaporation model. As a turbulent combustion model, a flamelet/progress-variable approach which considers 274 chemical species and 1537 elementary reactions is used. The results show that as the ambient pressure increases, gas temperature increases and consequently droplet evaporation and soot production are enhanced in the upstream region.

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In order to design a combustion chamber of rocket engine, it is very important to predict wall temperature and wall heat flux. In this research, numerical simulation for non-adiabatic turbulent combustion flow was conducted to validate combustion model. Conserved scalar model based on flamelet approach was expanded and applied to predict wall heat flux. To calculate turbulence, conserved scalar model was coupled with Large Eddy Simulation. As a result, typical structure of non-premixed flame was predicted by numerical simulation. In addition, thermal boundary layer was also predicted in the region near the non-adiabatic wall. The prediction of wall heat flux showed qualitative agreement with experimental result. It suggests that expanded conserved scalar approach coupled with LES has possibility to predict wall heat flux correctly.

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Multilayer ceramic capacitors (MLCCs) are used very widely as electric devices on printed circuit boards (PCBs). Impact loads are applied on MLCCs during PCB manufacturing processes with fast mounting machines or floor dropping of mobile appliances and MLCCs may crack sometime due to the mechanical design. In this paper, impact stresses, which were induced in MLCCs under ramp loads with a split Hopkinson bar impact test equipment attached a buffer solder material, were analyzed with large scale parallel computing method.

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Through holes were formed in printed circuit board for electric signal communication. The surface of through hole was plated by thin metal and the irregularities were shaped on the free-surface or on the interface by hole-drilling in printed circuit board. Fracture of through hole was occurred by stress concentration due to its irregularity. In this study, elastic-plastic thermal stress simulation was performed by using a large scale simulator ADVENTURECluster which was based on FEM to study fatigue strength around through hole in printed circuit board.

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Carbon nanotube (CNT) is expected to use as the materials of nano-scale components of electronic devices. In this study, we investigated the damage mechanism of Multi-walled (MW) CNT structures used as nano-component of electronic devices. An acceleration testing system of direct current loading was designed and the test structures collected MWCNT at the gap of Pt thin-film electrodes were treated in the system. The damage mechanisms of MWCNT are regarded as the effects of oxidation by Joule heating and/or the electromigration (EM) by high-density electron flows. Therefore the tests were conducted under the two kinds of current density and temperature conditions, and furthermore in both of air and low oxygen conditions. Lifetime of the specimen was determined by voltage measurements during the acceleration tests under the constant current condition. Their fracture phenomena were evaluated by means of microscopic observations. As the results, the amounts of lifetime of MWCNT were longer in the lower oxygen concentrations than in the air condition. In the microscopic studies, it was confirmed that the disconnections of MWCNT were occurred at the cathode side of the MWCNT structures under low current density, and the center area of MWCNT under high current density. Both types of damage morphologies induced by oxidation and EM were observed at the damaged MWCNT.

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Characteristic of nanowire is gradually attracting many researchers with potential applications of nano devices, nano sensors, solar sells and so on. This paper describes fabrication and evaluation of Cu nanowire surface fastener grown in porous aluminum. To fabricate nanowire surface fastener, at first BGA electrode patterns are fabricated on the resist on Si wafer by photolithography. Next, Cr and Au films were evaporated on the patterned side of Si wafer as a conductive working electrode. After that, the wafer was lifted off using acetone. Nanowire surface fastener was formed via electrical deposition in copper sulfate aqueous solution. After etching in 3 M NaOH aqueous solution to remove porous aluminum, we obtained nanowire surface fastener on Si wafer perpendicular to its surface. High density Cu nanowires with average diameter of 80 nm were observed by scanning electron microscope. In order to understand the performances of Cu nanowire surface fastener, electrical and mechanical properties of them were studied in details.

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In recent years, the size of electrical devices has evolved into the micrometer-scale and their circuit electrical wirings are also becoming smaller. The sizes of the wirings are on the nanometer order. The electrical resistivity becomes larger and the failure current density become smaller because of the size effect on grain boundary scattering. So in this study, we proposed the application of single crystalline aluminum nanowire as electrical wiring in the circuit. High quality Al nanowires were fabricated by simply heating the Al film. The driving force is determined by the compressive stresses caused by the thermal expansion mismatch between the Al film and Si substrate. The range of heating temperatures was between 473 and 583 K and the heating time was approximately 3 h. After heating, we observed numerous Al nanowires on the film surface by using the scanning electron microscope. We determined the relationship between heating temperature and Al nanowires growth. By using TEM, we confirmed that the Al nanowires were single crystalline. In order to understand the performance of individual Al nanowires, their electrical properties were also studied in detail.

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The strength of fine-solder joints in high-density mounting boards is affected by the existence of the Cu/Sn intermetallic compounds (IMCs) generated in the boundary between the solder and the copper electrode. Then, the deformation characteristics of the IMCs must be considered in the finite element analysis (FEA) for evaluating the strength reliability of the fine-solder joints. To conduct such an analysis, any experimental method which can obtain the tensile deformation characteristics of the IMCs is needed. This study proposes a method which employs a miniature solder specimen the cross-section of which has concentric layers of Cu/Sn IMCs and Cu electrodeposit. Three types of specimen each of which has different thicknesses of the concentric layers were prepared, and tensile tests using them were conducted. Since the specimens could be regarded as a composite material, a method in which the tensile characteristics of the specimens were applied to the rule of mixture (ROM) was proposed to evaluate the tensile deformation characteristic of the Cu/Sn IMCs.

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In this study, Direct-Current Potential Difference Method (DC-PDM) was proposed for quantitative evaluation of crack initiation and propagation on joining between copper-cored lead-free solder ball and copper plate specimen when copper plate specimen was subjected to cyclic tension. Finite element method was used for three dimensional potential analysis to clarify the relationship between change in potential difference and change in crack depth. In addition, influence of crack depth and joint condition on potential difference was considered. It was found that the relationship between crack size and potential difference is represented by a master curve with modification coefficient of core independently of joint condition.

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Mechanical reliability of electronic packages is one of the most important problems for the reliability of electronic products. Reduction of the warpage of an electronic package is useful to increase its mechanical reliability. The warpage of an electronic package often shows a hysteresis curve during a thermal cycle. However, it was difficult to simulate the hysteresis. In this study, we performed the viscoelastic analysis of a bonded sample of Si chip and underfill resin. This sample shows the hysteresis of the warpage during a heating and cooling heat cycle. We measured the master curves of the relaxation modulus using Dynamic Mechanical Analyzer (DMA) before and after heating. Then, we analyzed the warpage of the specimen with considering the change of the master curve of relaxation modulus of the underfill resin. The hysteresis of the warpage of the bonded specimen was well expected using the proposed method.

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A lot of semiconductor packages are used for electronic parts in telecommunication equipment. Semiconductor packages are made of different kinds of material which form multilayer laminate in structure. The warp has developed difference of physical properties of material. Thermosetting-resin of epoxy resin is mainly used for the encapsulant of semiconductor package. In this report, warp has developed noteworthy by cooling process and layer structure. The model is simple two-layer-laminated structure, which is the subject of an experiment in an epoxy resin/steel. These laminated structures heat at constant temperature of 180℃, and a chain of thermal loading until cooling is given. As a result, the theory is possible to estimate warp deformation of laminated structure.

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The Warpage behavior for viscoelastic three-layer laminated structure consisting of steel/epoxy resin/printed board which modeled electronic devices simply caused by a series of thermal load from heating to cooling was examined experimentally. On another front, its warpage behavior was calculated by thermo-viscoelastic stress/deformation analysis program based on linear viscoelastic theory which developed by ourself. And, those experimental values were compared with the theoretical values. As a result, it was clarified that the experimental values of warpage are good agreement with the thermo-viscoelastic analysis values. In addition, the warpage behavior of viscoelastic three-layer laminated structure are influenced not only by the material properties such as glass transition temperature, modulus of longitudinal elasticity and thermal expansion coefficient which are depended on temperature and flexural rigidity based on the thickness, width of three-layer laminated structure.

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This study conducts a measurement of a performance of a piezoelectric micro blower. Mobile electronic equipment becomes smaller and thinner while their functions become more complex. As a result, a lot of components are mounted in an enclosure and flow passages for the cooling air become narrow. This causes significant pressure drop and general cooling fans cannot supply enough cooling air. We focused on a novel piezoelectric micro blower. In order to predict accurate cooling performance of the piezoelectric micro blower in thermal design, we tried to develop the measurement system of the performance characteristic curve of the blower. By using our system, we succeeded to measure the relationship between the supply flow rate and the static pressure rise of the micro blower.

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This paper discusses modeling of transient thermal resistance behavior aiming at microprocessor silicon die temperature prediction. Temperature gradient prediction between two different-sized objects along heat conduction paths is one of key factors to obtain calculation result with practical accuracy in transient state. It is referred as thermal spreading resistance in this paper and modeling of its transient behavior is investigated as a part of one-dimensional thermal network with average temperature nodes which is introduced in previous work of this research.

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This paper describes experiments and the analysis of the heat transport capability of axial grooved heat pipes. The heat pipes were made of copper tubes with axial grooves and working fluid was H_2O. Outer diameter and length of the heat pipe were 8mm and 300mm. The width and height of the grooves were 0.19mm and 0.2mm and the number of grooves was 75. The effects of the fluid inventory, inclination angle and working temperature on the capillary limit were investigated. The following conclusions were obtained from the experiment and theoretical analysis. (1) The heat pipe showed maximum heat transfer rate of 100 W at 200℃ working temperature under horizontal setting condition and can operate under inclination of 70mm height difference at 50℃ working temperature. (2) The maximum heat transfer rate was increased in proportion to fluid inventory due to the increasing length of the liquid slug generated at condenser end. Evaporative and condensing heat transfer coefficients were also investigated experimentally.

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Flow soldering process with a simple model has been studied using CFD. Through-hole printed circuit board with surface mounted components is the object of this study. In this process, surface mounted components are soldered first and covered with a mask; then through-hole components without a mask is soldered by dipping the board into a solder bath. We to investigate the solder flow in narrow aisle between the masks. The effect of computational domain is clarified. Flow in solder causes surface deformation and increases surface rise rate.

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There have been many reports on Taylor vortex flow, and Taylor vortex flow in non-Newtonian fluid has recently been a popular target of research. For example, some researchers have reported the application of Taylor vortex flow to a mixing device for realizing a photosynthetic bioreactor. As applied research on Taylor vortex flow has thus been carried out, it is highly significant to study the behavior and pattern of Taylor vortex flow in non-Newtonian fluid as basic research. In this study, we analyzed the behavior of Taylor vortex flow in non-Newtonian fluid. The upper end wall of the cylinder used in this study is free surface. The lower end wall is fixed surface. The aspect ratio is 4.0. The Reynolds number changes from 1500 to 3000. The mass of the paper changes from 0.01 to 0.02 g increasing by increments 0.01 g. In the case of the distilled water, normal 5 cell mode appears every condition. When pieces of paper were added into the water, four different types were obtained.

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In a study of a flow caused by a rotating disk in a casing, as for many of past studies, most of the form of the rotating disk is not considered. However, it became clear by the study of late years that a radial gap affected the flow between the casing base and rotating disks greatly. In this study, we used the rotating disk having different forms and changed the size of the gap in the cylinder casing and tested it about the influence that the radial gap gave to the flow near the fixed disk. As a result, it has been observed that "bead-like-vortex" is generated in a disk. "Bead-like-vortex" is investigated in detail and the result of the experiment and PIV analysis is shown in this paper.

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The purpose of the study is to clarify the fluctuation phenomenon of the interface between two immiscible fluids in the rotating cylinders by using the experimental flow visualization and the image analysis. In this system, the inner cylinder can rotate and the outer cylinder is stationary. The cylinders are set coaxial and perpendicular. Both ends of the cylinders are stationary walls. Silicone oil and glycerin solution are used as working fluids. Glycerin solution was dyed with black ink to visualize the interface. The Reynolds number is based on the kinematic viscosity of silicone oil, the rotational speed of the inner cylinder and the length of clearance of the cylinders. When the Reynolds number reaches at a critical number, the interface starts on a fluctuation phenomenon in the neighborhood of the outer cylinder. The digital video camera is used to capture movies of developments of the fluctuation and image analysis is carried out. Amplitudes of the interface are estimated and critical Reynolds numbers of the onset of the fluctuation are determined on several aspect ratios.

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Vapor is formed in low and/or negative pressure regions in liquid phase. The formed vapor shrinks and disappears under increasing pressure condition. The former phenomenon is called cavitation and the latter is done vapor collapse. The vapor collapse causes noise and erosion. The vapor collapse processes in pseudo three dimensional model are simulated by molecular dynamics method with periodic boundary condition. The cylindrical shape vapor is mainly approximated to the vacuum. The vapor collapse processes are observed by using configuration of physical quantity mapped molecules. During vapor collapse process, atom level temperature becomes high and atom level potential energy does low at the gas/liquid interface. Just after the disappearance of the vapor, atom level temperature and potential energy increase at the center of the disappeared vapor in liquid phase. The distributions of physical quantities of molecule are transferred to continuum quantities under cylindrical coordinate.

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With the increase in the size of simulation results database, it has become a big challenge to transfer large data between different locations. In this study, we have developed a data compression method based on tensor compression. Voxel simulation results data are represented as third-order tensors and a tensor decomposition algorithm based on HOOI is applied to the tensors. After tensor decompression, the original tensor is decomposed into a core tensor and a series of basis matrices, whose summed size is considerably smaller than that of the original tensor. As a result, a compression ratio of over 60:1 is achieved for steady flow simulation and the error is below 5%. A compression ratio of over 70:1 is achieved for unsteady flow simulation and the error is below 5%. We have confirmed that no significant information is lost during the data compression process.

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Most studies about the state of the arts of visualization techniques will focus on the processing of the huge amount of data. In such studies, the treatment of particle tracking data has been an issue. In this paper, we attempt to reduce the amount of data using several clustering methods.

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A visualization software for evaluating computational fluid dynamics (CFD) results was developed. Recently, progress of computer performance and CFD software enables to execute large-scale computation. However, the results of these computations tend to be enormous and difficult to be evaluated in detail. In order to reduce those results, proper orthogonal decomposition (POD) has been investigated. A small set of simulation results is analyzed by POD and grouped by the indicator of eigenvector. In this study, a visualization software for POD results was developed and applied to the unsteady flow analysis results of a optical disc drive model. The original results were reduced to 30% of original data and efficiently visualized by using this software.

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Visualization of numerical simulation data is indispensable to intuitively understand natural phenomena. In this study, state-of-the-art visualization techniques to represent ocean general circulation model will be introduced. We have developed a multi-dimensional color map to visualize ocean currents effectively. In order to extract feature emphasis regions, a cluster analysis method, which is one of multivariate analysis, has also been developed. The multi-dimensional color map is optimized using extraction result.

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Cofilin, one of actin-binding proteins, promotes depolymerization and severing of actin filament. The filament disassembly is essential for turnover of actin cytoskeleton. In addition, it is also reported that cofilin binding alters torsional structure of actin filament. It is reasonable to think that the change of molecular behavior of actin filament induced by cofilin binding is associated with promotion of filament disassembly. Therefore we analyzed the relationship between them by use of molecular dynamics simulation. We performed equilibration simulation of cofilin-free and cofilin-decorated actin filament. For the purpose of discussing the relationship between torsional behavior and disassembly of actin filament, we calculated local twist angle of actin filament and interaction energy between adjacent actin subunits. The interaction energy indicates the extent of filament disassembly. From the simulation results, twist-dependent energy landscapes between adjacent subunits were observed in both cofilin-free and cofilin-decorated actin filament. High energy states near one specific twist angle are observed only in cofilin-decorated actin filament, which shows the disassembly of actin filament caused by cofilin binding. Additionally, another energy landscape was observed between cofilin and actin in cofilin-decorated actin filament, which accounts for the high energy states between adjacent actin subunits.

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