The fundamental possibility of physical simulation of wall‐free concentrated air vortices under laboratory conditions was demonstrated. Video filming is used to investigate the dynamics of air vortices which arise over a heated underlying surface as a result of unstable stratification of air. Various types of trajectories of motion of the base of vortex structures are revealed. Parameters are analyzed such as the temperature of underlying surface, the region of emergence of vortex structures, the lifetime, and the direction of motion, which define the type of trajectory of vortex base.
We developed a 1-kHz frontend and a 30-Hz pump source for a mJ-class mid-IR source. A KTA-based optical parametric amplifier system generated 10-μJ pulses at 3.4-μm. A novel Ti:Sapphire chirped-pulse amplifier produced 70-mJ pulses.
Procedures were developed and tested for detecting changes in land cover by using multitemporal Landsat MSS data. Our main concern Is to detect the occurrences of seasonal changes and long-term changes in land cover. Four observation dates by Landsat were selected in spring and winter at an interval of 7 or 8 years. Four bands of MSS were used for each date. CCT values were transformed to the values comparable to spectral reflectances by using references. The change detection.procedures proposed here use no training data, and are pre-classification methods. In one procedure spectral differences are calculated at each pixcl between every two dates out of four by using an Euclidean distance norm of the four band data. From these norms the spectral changes among the four dates are checked in every pixel. and seasonal and long-term changes are detected. Principal component procedure is also tested.
[1] A 7.2-magnitude earthquake occurred on the plate boundary off Miyagi Prefecture, northeastern Japan, on 16 August 2005. From seafloor geodetic observations using the GPS/acoustic combination technique in this area, we have detected notable seafloor movements associated with, and subsequent to this event. The time series of horizontal coordinates obtained at the seafloor reference point MYGW, located about 10 km east of the epicenter, indicates that the strain accumulated for the interseismic period was partly released by the event and a constant strain accumulation restarted after 1–2 years of the post-seismic period with an erratic movement. The horizontal velocity of MYGW after the restart above is estimated to be about 5.7 cm/year toward WNW relative to the Eurasian plate. Our result is consistent with those derived from terrestrial GPS measurements and implies that the interplate locking was restored in the rupture area of the 2005 event around 2007.
A multi-channel electro-osmotic flow (EOF) implemented to the closed-channel cooling system (C 3 S) has been developed for thermal management of stacked chips (3D-ICs). The EOF pump, which was fabricated using MEMS technology, provided driving capabilities of fluid flow through the micro channel at the P max of 1 × 10 4 Pa and Q max of 38 μl/min. Cooling capability as high as 140 W/cm 2 was demonstrated for the first time.
Abstract Large clods (centimetres in size) can be formed by tillage in clayey paddy fields where upland crops are planted. These clods cause early water depletion near the soil surface, which decreases crop germination and emergence rates. Because of the difficulty in reducing clod size, desiccation damage to seeds can be avoided by adjusting the seeding depth based on the clod size‐dependent soil moisture profile. This study aimed to clarify the effect of clod size on (1) the evaporation rate ( E ) and soil moisture profile and (2) the mobility of soil water during the drying process. Evaporation experiments were conducted in an air‐conditioned greenhouse with natural light using cylindrical columns filled with artificially made clods 3 (L columns) and 1 cm (S columns) in diameter. We measured E , potential evaporation rate ( PE ), and total soil moisture content ( w tot ) throughout the experiment and the soil moisture profiles at the end of the experiment. The water diffusivity ( D w ) and apparent vapour diffusion coefficient ( d vap ) were calculated as the mobility of soil water and water vapour, respectively. We found that w tot was lower in the L column than in the S column, although not at the onset of the experiment. At the end of the experiment, the soil moisture content was lower in the L column than in the S column throughout the soil layer. In contrast, E / PE was higher in the L column than in the S column throughout the experiment and even at the same w tot . Regarding mobility, D w was slightly greater in the L column than in the S column in the soil moisture content range, where vapour movement could be greater than liquid water movement. In addition, the ratio of d vap to the diffusion coefficient of water vapour in soil was higher than unity in both columns and was 2.4–3.2 times higher in the L column than in the S column. In summary, larger clods caused a higher evaporation rate and lower soil moisture content, owing to the increased enhancement of water vapour movement probably induced by wind.
This paper represents a design and development of a mobile sensing unit as well as its prototype implementation for railway track monitoring. The unit consists of an ultra-small personal computer (PC), a global positioning system (GPS) receiver, an accelerometer and an ADC (Analog/Digital Converter) so that the unit can trace the route while capturing an acceleration response of a passenger vehicle. The unit enables more frequent and qualitative data acquisition compared with traditional and the state of the practice railway track inspection equipments. Locating disorder is the key of our unit, which has a reasonable accuracy of positioning with GPS data, existing facilities landmarks, and car acceleration responses. The proposed unit is a promising device for efficient properties management of railway agencies. The prototype implementation shows a result that car acceleration responses are related with the track displacements in low frequencies. The results also imply that sensor settlement on a vehicle floor, not axes or bogies, is effective for capturing track vertical displacements.
