The purpose of this study is to set up the device of the shock tube experiments with a converging section. Since the temperature of the gas behind a shock wave which is reflected from the end wall of the shock tube with a converging section is greater than that without the section, it is possible that this region is able to apply to processing of material. In order to examine the characteristics of the device in this study, Mach number of the incident shock wave propagating in the shock tube is measured by using piezoelectric pressure transducers. Furthermore, pressures behind the incident shock wave and the shock wave which is reflected from the end wall of the converging section are measured.

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The purpose of this study is to propose a practical technique for damping characteristic improvement on the packed with sand. In this paper, the damping characteristics of plate structures packed with sand are experimentally investigated. The packing spaces were made by hole drilling. The packing space for packing sand is discussed by computing the volume of drilling hole in plate structure. The effects of hole number and hole size on the damping characteristics are examined. The effective damping capacity improvement is achieved by packed sand of small size and many hole number. In the same packing space, when the hole size is small, there is many hole number. It is considered that the contact area between packed sand and the inner wall of hole is increase. The damping capacity improvement is realized by increase of the contact area.

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In_xGa_<1-x>N is well known as a material which can choose the energy band gap corresponding to the wave length of the blue light. In_xGa_<1-x>N is already used as an active layer of high intensive blue LED or blue Laser Diode. It is also found that, however, the quality of crystalline in this material is getting worse as increasing of indium composition (molar fraction) x. We have studied the compositional dependence of the optical phonon modes in cubic In_xGa_<1-x>N theoretically using by random element isodisplacement linear chain model. As the results, the theoretical fitting for LO and TO phonon modes is found a good agreement with the experimental data which showed "one-mode" type behavior. It was also shown in analysis of the oscillator strength of each TO phonon modes.

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The freshmen of our department for electrical and electronic engineering have assembled digital-multi-meter (DMM) kits since 1999 at Toyota National College of Technology. However, they were not able to understand the theory and mechanics of the DMM's, despite the fact that they were accompanied with good manuals. We developed the instructive dual-slope analog-to-digital (A/D) converter system, which converted circuits arranged on the plane surface of a rack, and we applied the system to the experiment in the lower grade. This paper consists of two sections. Section 1 describes the mechanics, the specifications, and the specific characteristics of the system. Section 2 describes the questionnaire investigation, for which the instructive A/D converter system is useful for students in the lower grades who lack expert knowledge. As a consequence of this experiment and investigation, the students responded well through the experimental approach. Also, the students understanding had increased dramatically.

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In recent years, two seismic reinforcement methods of the construction that fill up the concrete and add the steel reinforcing material inside the steel cylinder peer are general. The ductility of the structure is improved by their reinforcements. However, the horizontal ultimate strength increases at the same time. It becomes very likely that the damage occurs for the anchor under the ground and the base section. They are difficult to retrofit. It's necessary not only to control the increase of the horizontal ultimate strength, but also to improve the ductility in the method of the construction. In this study, the main purpose is confirming the seismic reinforcement effect statically and seismically about seismic reinforcement method suggested by our laboratory. And it shows the effective seismic reinforcement method of the cylinder steel peer by the FEM.

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The strains of the steel plate are generally measured by using the strain gauge. It is difficult to use the strain gauge when measurering about the strain distribution with the corroding steel plate. There is a necessity to consider about the measurement of the strain distribution when the tensile coupon test of the corroding steel plate is executed. In this study, the new method has been presented that using digital images to measure strain of steel plate, and the applicability of this new method was examined.

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A series of centriftige model tests were carried out to investigate the performance of multi-anchored reinforced soil wall due to seepage flow. The tests were conducted under several compact ratio of foundation and back fill part to realize the behavior of deformation pattern. In these tests, the catastrophic failures were not recognize in spite of the ground water level of upper stream of soil wall, because the reinforcement of anchor was fully worked against the slipping. However, there is no distinct difference between each test case, that compact ratio of 70-80%.

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A stiffening Method of existing cylindrical steel piers is studied by experimental ways. On the experimental way steel piers are stiffened by rectangular steel plates on it. On the Stiffening structures are set using the plates and local buckling points created forcibly on the pier. The part of the pier which yields local buckling is controlled in base zone of it by this Stiffening structures and the ductility of the piers are improved with small increase the ultimate strength of it. We have been able to improve the ductility of piers by the Stiffening structure.

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Wall mud strength influences to the restoring force characteristic of clay walls. The drying clay increases the wall mud strength. Nevertheless, the relation among a curing term, dryness, and a wall mud strength is not cleared adequately. The main objective of this report is the relation between a curing term and a wall mud strength. Results are as follows : the strength of the wall mud for an inner layer (Arakabe) is increased by a long curing term. The strength of the wall mud for an outer layer (Nakanuri) is not related to the curing term.

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The effects of the clay strength considering drying period to the horizontal force of mud walls are discussed in this paper. The strength tests of clay are both compression test and splitting test. These tests are executed in 1, 2, 3, 8, 12, 24 weeks. The horizontal force is calculated in consideration of the clay strength. The results are as follows: a long drying period makes the clay strength harder. And it also makes the horizontal force of mud walls high.

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In this paper, we estimated that how students understand and grasp an architectural drawing in the light of period of learning architecture, procedure of grasping the drawing, and method by eye fixation behavior. 1) The new students can not understand architectural drawings easily. But, it was objectively confirmed that the more time the students spend on their specialized studies, the more accurately they understand them. 2) The glance tracks (eye fixation place) of lower-grade students tend to concentrate on a specific part. In contrast, upper-grade students tend to watch them uniformly. 3) Lower-grade students understand the entire drawing by gathering partial information. And upper-grade students understand the detail after having caught the whole information. We observed such a tendency.

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[in Japanese]

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[in Japanese]

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Architects want the free shape for their architecture from the ordinary structural design. Free shape design needs the structural design agent system for their probability of structural limit. The prior study shows the both the scanning of a free shape and the creation of its structural analysis data. This report deals with the structural reasonableness of natural free shapes. As results, a seashell and a egg have a structural reasonable shape. The optimization is needed to make a proper shape from scanning data because of the initial imperfection. As there is the superficial shape which does not express its structural shape, architects must find its true structural shape.

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It is important for the decrease of seismic damage to retrofit buildings. Nowadays, the retrofitting is not performed efficiently, because of the high cost, defiling the functionality and beauty of buildings. To increase retrofitting buildings, it is significant to clarify the retrofitting method not to defile build ings. In this report, the image investigation for the 11 retrofitting structures. The Semantic Differential method is employed with 18 adjective pairs. The results may be summarized as follows: Half of ex aminee wants the 2.0 times seismic performance for "houses", and "schools". The high likability retro fitting methods is to conceal quake resisting elements, and the inconspicuous design of quake resisting elements.

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In this note, we define the determinant of matrices by induction on the (horizontal or vertical) dimension and the elementary row and column operations. We also present some class practice examples which use the definition and show that definition is strictly suitable for classes on determinant.

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[in Japanese]

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The purpose of this paper is to propose a teaching approach which will be effective to improve students 'proficiency. Firstly, this paper analyzes the findings of the investigation into the English learning of the students in Toyota National College of Technology, which was conducted in June, 2007, by emphasizing on the importance of improving students'proficiency in English by nurturing them as independent learners of English. Then, it proposes a type of teaching approach which will lead to the autonomy of students in English learning. Finally, it refers to a prototype of a computer-assisted material which the author has made and by which the users can re-experience the above teaching approach which might be an effective learning approach for the users as well.

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