The Young's modulus of a titanium nitride thin film has been investigated in this study by means of nanoindentation technique. Nanoindentation measurements have been coupled to analytical models and finite elements simulation to decorrelate the effect of substrate from the Young's modulus evaluation. Whereas analytical models did not lead to a converging solution towards experimental measurements, an identification based on finite elements calculations is shown necessary. Simulated contact stiffness versus contact areas have been fit with experiments and have led to a Young's modulus of 200±20 GPa for a 180 nm thin film of TiN deposited on a ‹100› silicon substrate. This study confirms the property of the TiN deposited in thin films to have a different Young's modulus from a bulk TiN. [DOI: 10.1380/ejssnt.2012.624]

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A measurement method of structural intensity was proposed by developing the signal processing in near-field acoustical holography (NAH) in our previous paper [Jpn. J. Appl. Phys., 35, 3167-3174 (1996)]. The present paper extends that method to the structural intensity measurement in cylindrical geometry. Two samples used in the experiment are SUS304 cylindrical shells. One of them has a rib and the other has no rib. The experimental data are obtained and reconstructed over the frequency range between about 300 and about 3, 000 Hz. The data at 488 Hz and 1, 877 Hz are selected for specific and detailed investigation of structural intensity distribution, where 488 Hz lies in a pass band and 1, 877 Hz in a stop band of the ribbed shell. According to the discussion of experimental results, it may be understood that the attached rib acts as a “light beam” at a pass-band frequency 488 Hz and a part of the intensity flow is reflected at and the rest is transmitted through the rib. However, the rib almost completely reflects the intensity flow by acting as a “heavy beam” when the driving frequency is a stop-band frequency 1, 877 Hz. The overall modecell structure is thus largely influenced by the action of a rib except for locally induced vortexlike structure. Also, the calculation of the power injected to the shell successfully leads to the identification and localization of the vibration source

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Electromagnetic levitation of electrically conductive droplets by alternating magnetic fields is a technique used to measure the physical properties of liquid metallic alloys as heat capacity and thermal diffusivity, among others. In order to reduce electromagnetic stirring and shaping of the molten sample, experiments are conducted in microgravity 1). Measurement is performed by using the modulation calorimetry technique [2][3]. Here we test both numerically and experimentally a new measurement protocol, which aim is to eliminate calibration. We use this procedure to demonstrate that the use of a levitator in a DC magnetic field overcomes the negative effects of the electromagnetic stirring inside the sample on the accuracy of the modulated calorimetry technique.

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The modelling of processes involving powder needs taking into account the particulate nature of the materials involved. The Discrete Element Method (DEM) is well suited for this task. It allows the macroscopic behavior of an assembly of particles to be calculated from the contact forces generated between each particle. Particle rearrangement, a significant signature of powder materials, is explicitly taken into account. We show that DEM has demonstrated use and significant potential for understanding the link between defect formation and initial microstructure. We present diverse examples of application on free and constrained sintering.

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Allergic rhinitis is a condition which shows a high prevalence throughout the world. Once a person is sensitized to a specific allergen, spontaneous resolution of the allergy occurs only very rarely and this results in a steady accumulation of patient population. Worldwide attention to this affliction is being paid from both the medical and the economic perspectives. In Japan, the most typical seasonal allergic rhinitis is caused by cedar pollen during the spring months of late February to early May. Rough estimates of a 15 to 20% prevalence rate have been reported and hence Japanese cedar pollinosis is deemed as a national disease. The efficacy and cost-effectiveness of the treatment are of great concern to the social medical system of Japan. Previously there have been several reports regarding the cost-effectiveness of new medications and desensitization immunotherapy. The authors have previously reported their experience of treating allergic rhinitis with the Nd:YAG laser and its efficacy. However there are no reports, as of yet, on the cost-effectiveness of this procedure. The authors compared the costs of three typical treatment protocols for cedar pollenosis: Nd:YAG laser treatment, anti-histamine prescription and desensitization immunotherapy. The results revealed that the direct costs associated with the Nd:YAG laser treatment were less compared to the two other treatment protocols. The authors also believe that the indirect economical losses associated with allergic rhinitis such as loss of work force for hospital visits was also lessened with the Nd:YAG laser treatment.

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