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61.
The Earth Simulator (ES) is a large scale, distributed memory, parallel computer system consisting of 640 processor nodes (PN) with shared memory vector multi-processors (64GFLOPS/PN, 5120 APs in total, AP: arithmetic processor). All the nodes are connected via a high speed (16GB/s) single-stage crossbar network called the Interconnection Network (IN).

The operating system for the Earth Simulator is based on SUPER-UX, the UNIX operating system for the SX series scientific supercomputers. In order to realize high-performance parallel processing on the highly parallel machine, the operating system is enhanced for scalability.

The Earth Simulator system is managed as a two-level cluster system called the Super Cluster System. In the Super Cluster System, the Earth Simulator system is divided into 40 clusters (16 PNs/cluster). A single controller called Super Cluster Control Station (SCCS) manages all these clusters. This management system provides Single System Image (SSI) operation, management and job control for the large scale multi-node system.

The Job Scheduler (JS) and NQS running on the SCCS control all jobs of the system. They schedule the resources such as processing nodes and files which have not usually been treated as scheduling resources. This allows efficient scheduling of large scale jobs.

The MPI library (MPI/ES) and the HPF compiler (HPF/ES) are available for distributed parallel programming on the Earth Simulator. MPI/ES conforms to the MPI 2.0 standard and is optimized to exploit the hardware features. HPF/ES conforms to the core part of HPF 2.0 and supports some features of the HPF 2.0 approved extensions and HPF/JA 1.0 extensions. HPF/ES suitably handles the 3-level parallelism of the Earth Simulator system, that is, vectorization, shared-memory parallelization, and distributed-memory parallelization. Moreover, HPF/ES extends the language to easily handle irregular problems.  相似文献   

62.
La1−xCaxVO3 composition-spread film library was fabricated by combinatorial pulsed laser deposition and their thermoelectric properties were evaluated paralelly by the multi-channel probes of Seebeck coefficient and electric conductivity. Concurrent X-ray analysis verified the formation of solid soluted films in the full composition range (0x1) as judged from the linear variation of the lattice constants. The Seebeck coefficients of La1−xCaxVO3 changed from a large negative value to almost zero with the increase of x, due presumably to the variation of valence in vanadium ions.The power factor in this library was as high as 0.6 μW/cm K2, which was obtained at x=0, i.e. pure LaVO3 grown at 800 °C.  相似文献   
63.
Magnetic properties were investigated for the rare-earth 3d-transition metal oxides with the perovskite structure. Intriguing magnetic phenomena were reviewed for a few systems:magnetization peak effect in the titanates, magnetization reversal in the chromites and metallic ferromagnetism in the cobahites. The results suggest an important role of the rare-earth ions for the magnetic properties of such complex oxides.  相似文献   
64.
One of the objectives of the high-temperature engineering test reactor (HTTR) is to demonstrate the effectiveness of high-temperature nuclear heat utilization, which aims to extend the application of nuclear heat to non-electric fields, especially to hydrogen production. As part of the development of the hydrogen production processes, laboratory-scale experiments of a high-temperature electrolysis of steam (HTES) had been carried out with a practical electrolysis tube with 12 solid-oxide cells connected in series. Using this electrolysis tube, hydrogen was produced at the maximum density of 44 N cm3/cm2 h at a electrolysis temperature of 950 °C. Thereafter, to improve hydrogen production performance, a self-supporting planar electrolysis cell with a practical size (80 mm × 80 mm of electrolysis area) was fabricated. In the preliminary electrolysis experiment carried out at 850 °C, the planar cell produced hydrogen at the maximum density of 38 N cm3/cm2 h, and the energy efficiency was almost as high as that obtained with the electrolysis tube at 950 °C. However, both electrolysis tubes and planar cells did not keep their integrity in one thermal cycle. Durability of the solid-oxide cell against the thermal cycle is one of the key issues of HTES.  相似文献   
65.
Bending behavior of steel pipes filled with ultralight mortar was studied by bending tests using a steel pipe, steel pipes filled with ultralight mortar, and steel pipes filled with light aggregate concrete and normal concrete. The steel pipe model filled with normal concrete had 1.8 times higher bending strength than the steel pipe model. The bending behavior of the steel pipe filled model with ultralight mortar was not improved when the compressive strength of the ultralight mortar was less than 1 MPa. However, ductility was much improved when the compressive strength was over 5 MPa, and the ultimate steel strain was more than double of the steel pipe model. The strains of steel and concrete in all the models were proportional to the distance from the neutral axis until the steel plate yielded. A simple analytical method was proposed to calculate the bending moments of the ultralight mortar filled steel pipes. The calculated values agreed very well with the test results.  相似文献   
66.
Remote sensing of vegetation and land-cover change in Arctic Tundra Ecosystems   总被引:12,自引:0,他引:12  
The objective of this paper is to review research conducted over the past decade on the application of multi-temporal remote sensing for monitoring changes of Arctic tundra lands. Emphasis is placed on results from the National Science Foundation Land-Air-Ice Interactions (LAII) program and on optical remote sensing techniques. Case studies demonstrate that ground-level sensors on stationary or moving track platforms and wide-swath imaging sensors on polar orbiting satellites are particularly useful for capturing optical remote sensing data at sufficient frequency to study tundra vegetation dynamics and changes for the cloud prone Arctic. Less frequent imaging with high spatial resolution instruments on aircraft and lower orbiting satellites enable more detailed analyses of land cover change and calibration/validation of coarser resolution observations.The strongest signals of ecosystem change detected thus far appear to correspond to expansion of tundra shrubs and changes in the amount and extent of thaw lakes and ponds. Changes in shrub cover and extent have been documented by modern repeat imaging that matches archived historical aerial photography. NOAA Advanced Very High Resolution Radiometer (AVHRR) time series provide a 20-year record for determining changes in greenness that relates to photosynthetic activity, net primary production, and growing season length. The strong contrast between land materials and surface waters enables changes in lake and pond extent to be readily measured and monitored.  相似文献   
67.
The deuterium trapping behaviors in tungsten damaged by light ions with lower energy (10 keV C+ and 3 keV He+) or a heavy ion with higher energy (2.8 MeV Fe2+) were compared by means of TDS to understand the effects of cascade collisions on deuterium retention in tungsten. By light ion irradiation, most of deuterium was trapped by vacancies, whose retention was almost saturated at the damage level of 0.2 dpa. For the heavy ion irradiation, the deuterium trapping by voids was found, indicating that cascade collisions by the heavy ion irradiation would create the voids in tungsten. Most of deuterium trapped by the voids was desorbed in higher temperature region compared to that trapped by vacancies. It was also found that deuterium could accumulate in the voids, resulting in the formation of blisters in tungsten.  相似文献   
68.
A 42-year-old male was admitted to our hospital because barium esophagograpm showed an esophago-bronchial fistula with an esophageal deverticulum. He has had frequent episodes of cough at drinking water since childhood. A chest CT scan showed mild inflammatory change and bronchiectasis in the right S6. Division of the fistula by video-assisted thoracoscopic surgery (VATS) was performed. There was no evidence of inflammation and adherent lymph nodes around the fistula. This case was diagnosed as a congenital esophago-bronchial fistula by operative findings and clinical course. The fistula was dissected easily and divided by an auto-suturing instrument. The affected lung could be preserved. The patient was discharged on the 10th postoperative day. VATS is an effective treatment for the patients of congenital esophago-bronchial fistula (Braimbrige type I and II), if they are not accompanied with pulmonary abscess or pleural empyema.  相似文献   
69.
Previously, we demonstrated that the proton pump inhibitor, esomeprazole magnesium hydrate (MH), could have potential as a repurposed treatment against preeclampsia, a serious obstetric condition. In this study we investigate the difference in the preclinical effectiveness between 100 µM of esomeprazole MH and its hydration isomer, esomeprazole magnesium trihydrate (MTH). Here, we found that both treatments reduced secretion of sFLT-1 (anti-angiogenic factor) from primary cytotrophoblast, but only esomeprazole MH reduced sFLT-1 secretion from primary human umbilical vein endothelial cells (assessed via ELISA). Both drugs could mitigate expression of the endothelial dysfunction markers, vascular cell adhesion molecule-1 and endothelin-1 (via qPCR). Neither esomeprazole MH nor MTH quenched cytotrophoblast reactive oxygen species production in response to sodium azide (ROS assay). Finally, using wire myography, we demonstrated that both compounds were able to induce vasodilation of human omental arteries at 100 µM. Esomeprazole is safe to use in pregnancy and a candidate treatment for preeclampsia. Using primary human tissues and cells, we validated that esomeprazole is effective in enhancing vascular relaxation, and can reduce key factors associated with preeclampsia, including sFLT-1 and endothelial dysfunction. However, esomeprazole MH was more efficacious than esomeprazole MTH in our in vitro studies.  相似文献   
70.
This paper describes three-dimensional microstructures fabricated using a simple self-assembly process involving the thermal shrinkage of polyimide. The proposed method enables hinged structures to be automatically rotated out of the wafer plane and to remain bent without the need to use any interlocking mechanisms. The hinged structures were fabricated using surface micromachining techniques involving heating in a furnace. An increase in the bending angle due to the shrinkage of polyimide was observed with increasing heating temperature, heating time, and length of the polyimide hinge. Of these three parameters, the heating time was found to be the most suitable for precise control of the bending angle. Furthermore, microcubes were fabricated by this method and the self-assembly process was successfully visualized using a CCD camera.  相似文献   
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