SEIS CENTÍMETROS: UMA ANALÍSE ANTROPOMÉTRICA DA POF 2002- 2003

This paper analyzes the heights of the Brazilian people using anthropometric and economic data from the Pesquisa de Orçamentos Familiares (POF) 2002-2003. The literature suggests that height is a good proxy of the physical life conditions of the populations. The tabulations of POF microdata indicate that the difference among the heights of 21 and 65-year-old men is circa 6 centimeters. The same value, by chance, represents the difference on the stature of the poorest and richest quintiles. There are also steady regional differences; in the North and Northeast, the heights are about 2 centimeters lower than the national average, for any cohort. Regression analyses show that proxy variables related to life conditions during body growth and regional dummies were statistically significant causes of the variation on the height of individuals. In contrast, color, urban/rural and inequality variables were not significant. The results replicate what the historiography on life conditions and stature says: the social environment has a significant impact on the average height of the populations.

A Novel Type of Mechanical Power Transmission Array for Switching Densely-Arrayed Actuator Systems

This paper proposes a novel type mechanical transmission system for driving arrayed elements. The main advantage of this system is that it is able to operate individually arrayed elements with high-power. It was fabricated by MEMS technologies, and was confirmed that we are able to individually drive the arrayed elements by selectively driving tulip-shaped electrostatic clutch devices that transmit large power coming from a single power source. The transmitted stroke was 20 μm for this experiment.journal articl

Characteristics of On-Wall In Tube Thermal Flexible Mass-Flow Sensors

We developed a wall-mounted in-tube thermal flexible sensor for measuring mass flow that can measure the flow rate in both hydraunlically developing and fully-developed regions. The flexible structure was achieved by using polymer MEMS technologies. It has high linearity with a TCR of 0.0026K^{-1}, and a steady maximum value for the response time is reached within 7μs. The measuring distance from the tube entrance is 8.3 D (D=inner diameter of tube). This is much shorter than 64D, the theoretically calculated distance necessary for the formation of a fully-developed flow condition.journal articl

Glove Type of Wearable Tactile Sensor Produced by Artificial Hollow Fiber

We previously proposed an artificial hollow fiber, as a new MEMS material, for the development of a fabric tactile sensor. The artificial hollow fiber is fabricated by uniformly laminating metal and insulation layers onto the surface of an elastic hollow fiber. The fabric tactile sensor is made by weaving the modified hollow fibers into a cloth. The sensor can detect the contact force by measuring changes in capacitance at the points where the warp and weft fibers intersect, and can detect 2D contact force distribution by sequentially scanning the capacitance changes at all intersecting points. We investigated the dependence of sensor output on normal load and tension. The normal load and tension were independently applied to the fiber elements in order to determine the basic characteristics of the fabric sensor. We also developed two different glove-type wearable tactile sensors. One was made by patching the sensor onto an existing glove, and the other was made by directly weaving the hollow fibers into the yarn of the glove. In experiments with the patched sensor, we confirmed that it was able to detect contact force.journal articl

Effects of Environmental Condition on the Strength of Submicron-Thick Single Crystal Silicon Film

We developed a quasi-static tensile test system that controls environmental conditions, such as pressure, temperature, and surrounding gasses. Using this system, we evaluated the fracture properties of micron- and submicron-thick single-crystal-silicon film under several conditions. The strength of silicon measured in vacuum or helium was slightly higher than that in laboratory air. We measured the fracture toughness at different temperatures ranging from room temperature (RT) to 500ºC and found a brittle-to-ductile transition at 70ºC for micron-sized silicon film. The fracture toughness drastically increased at the transition temperature and saturated at a level of 2.5 MPa √ m , which is twice the value at RT. On the other hand, submicron-thick silicon was less brittle: its fracture toughness was already 2.7 MPa √m at RT.journal articl

Electrostatic Latch Mechanism for Handling Projection on Arrayed Vertical Motion System

We have previously proposed an arrayed vertical motion system based on a tulip-shaped electrostatic clutch for producing haptic displays. The system has an advantage in that it is able to individually operate arrayed end-effecter elements with high-power and large strokes (Output: 600 mN and displacement: 60μm). We added a new electrostatic latch mechanism to the system to individually control the projection state. We used MEMS technologies to fabricate a 4x4 array electrostatic latch mechanism. The total size of the mechanism was 6.0 x 6.0 x 0.5mm. We evaluated the relationship between the applied voltage and a holding force of a few mN was obtained for the spring device.journal articl

Micro-Machined Stent-Type Flow Sensor for Evaluation of Nasal Respiration

We present a thermal flow sensor that is suitable for measuring nasal respiration. To fix the flow sensor inside the nasal passage, we integrated it onto a stent structure, which is normally used as a medical device. The sensor was monolithically integrated on the Ti substrate by applying photolithography and wet etching processes. The developed fabrication has advantage that it is able to fabricate the both of the cavity for the thermal isolation and the stent structure during the same process. We mounted the flow sensor onto the inner surface of the silicone tube by inflating the balloon tube. The mechanical strength of the cylindrical stent under the compression condition was also studied, and it showed an elastic deformation when the force was less than 0.08 N. The developed flow sensor could detect the flow direction at the flow range of 0-2000 ccm. A response time of less than 260 msec was obtained by forming a cavity under the sensor.journal articl

Micromachined tube-type of Si droplet generator

We developed the novel type of droplet generator for the bio-chemical reactions, and designed it by considering Reynolds and Weber numbers. The Si droplet generator was fabricated on a silicon-on-insulator wafer by using deep-reactive ion etching and was fixed in a piece of heat-shrinkable tubing by heating the tubing. We experimentally confirmed that the fabricated droplet generator formed droplets in 1 mm diameter with jetting.journal articl

A Universal Parameter for Sillicon Anisotropic Etching In Alkaline Solutions

We propose a new explanation for the difference between the etching properties of potassium-hydroxide (KOH) and tetramethyl-ammonium-hydroxide (TMAH) by focusing on the volume fraction occupied by the corresponding cations, K＋ for KOH and TMA＋ (with molecular structure N(CH3)4＋) for TMAH. We have found experimentally that the differences in the surface morphology of Si(111) after etching can be explained by considering the cation volume fraction and that this parameter can also be used to explain the changes in the etch rates between different etchants, or between different concentrations of the same etchant, suggesting a universal behavior for any etching system. This finding simplifies the understanding of the mechanism of silicon anisotropic etching.journal articl

Characteristics of On-Wall In-Tube Flexible Thermal Flow Sensor at Wrap Pipe Condition

We previously proposed a novel type of on-wall in-tube thermal flexible sensor, and confirmed that it can measure the flow-rate in both hydraulically developing and fully-developed conditions[1]. This time, we investigated another outstanding advantage, i.e.the sensor is able to measure the flow-rate at axially asymmetric flow condition, and found that the sensor is applicable for the measurement of the flow-rate in bent tube condition.journal articl