Following the first‐time ionospheric imaging of a seismic fault, here we perform a case study on retrieval of parameters of the extended seismic source ruptured during the great M9.0 Tohoku‐oki ...earthquake. Using 1 Hz ionospheric GPS data from the Japanese network of GPS receivers (GEONET) and several GPS satellites, we analyze spatiotemporal characteristics of coseismic ionospheric perturbations and we obtain information on the dimensions and location of the sea surface uplift (seismic source). We further assess the criterion for the successful determination of seismic parameters from the ionosphere: the detection is possible when the line of sights from satellites to receivers cross the ionosphere above the seismic fault region. Besides, we demonstrate that the multisegment structure of the seismic fault of the Tohoku‐oki earthquake can be seen in high‐rate ionospheric GPS data. Overall, our results show that, under certain conditions, ionospheric GPS‐derived TEC measurements could complement the currently working systems, or independent ionospherically based system might be developed in the future.
Key Points
Parameters of seismic source can be deduced from 1Hz ionospheric GPS data
Ionosphere can visualize a multi‐segment structure of a seismic fault
CID velocity ~1.4 km/s points on either shock waves, or acoustic waves in water
Following the first-time ionospheric imaging of a seismic fault, here we perform a case study on retrieval of parameters of the extended seismic source ruptured during the great M9.0 Tohoku-oki ...earthquake. Using 1Hz ionospheric GPS data from the Japanese network of GPS receivers (GEONET) and several GPS satellites, we analyze spatiotemporal characteristics of coseismic ionospheric perturbations and we obtain information on the dimensions and location of the sea surface uplift (seismic source). We further assess the criterion for the successful determination of seismic parameters from the ionosphere: the detection is possible when the line of sights from satellites to receivers cross the ionosphere above the seismic fault region. Besides, we demonstrate that the multisegment structure of the seismic fault of the Tohoku-oki earthquake can be seen in high-rate ionospheric GPS data. Overall, our results show that, under certain conditions, ionospheric GPS-derived TEC measurements could complement the currently working systems, or independent ionospherically based system might be developed in the future. Key Points Parameters of seismic source can be deduced from 1Hz ionospheric GPS data Ionosphere can visualize a multi-segment structure of a seismic fault CID velocity ~1.4 km/s points on either shock waves, or acoustic waves in water
Understanding the formative factors of connectivity among deep-sea chemosynthetic communities may clarify the biogeographic mechanisms that facilitate the establishment and development of vent/seep ...fauna. This study identified interspecific differences in the geographical distribution and genetic population structure of 4 alvinocaridid shrimp species inhabiting hydrothermal vents in the Okinawa Trough, Northwest Pacific. Shinkaicaris leurokolos populations were widely distributed at 580 to 1651 m depth, with partial nucleotide sequences of the mitochondrial COI gene revealing extremely high genetic diversity (haplotype diversity: 0.98 to 1.00). In contrast, local populations of Alvinocaris dissimilis and A. longirostris, both of which have narrower bathymetric distributions, were characterised by low haplotype diversity (0.29 to 0.52). In the Okinawa Trough, Alvinocaris sp. only occurs at the Irabu Knoll, but this species also inhabits the Suiyo Seamount on the volcanic front of the Izu-Bonin Arc (Northwest Pacific). This undescribed species had relatively high haplotype diversity (0.70 to 0.82), with no genetic differentiation between the 2 sites. Certain factors may allow this species to occur at both sites (e.g. a chemical environment derived from similar substratum), despite geological differences in hydrothermal circulation (i.e. a back-arc basin versus an arc volcanic front, respectively). The findings of this study indicate that (1) the wide geographical and bathymetrical distributional ranges of the vent shrimp species cause high genetic diversity associated with stable population connectivity and (2) certain environmental features (e.g. depth and substratum) and life-history traits (e.g. feeding habitat and larval characteristics) represent important formative factors in the connectivity of alvinocaridids in the Northwest Pacific.
The treatment of spent electroless nickel plating baths has attracted much attention from the standpoints of environmental protection and nickel recycling. In order to design a nickel recovery ...process from the spent baths, the continuous extraction and stripping of nickel in the spent baths were carried out using a mixer-settler extractor. 2-Hydroxy-5-nonylacetophenone oxime (LIX84I) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC88A) were used as the extractant and the accelerator, respectively. The effects of the accelerator, flow rates and total stage number were investigated. It was found that the extraction efficiency was significantly increased by adding the accelerator. The extraction and stripping efficiencies were affected by the flow rates of the organic and aqueous phases, and its mechanism was qualitatively discussed on the basis of the stoichiometric relation of the extraction and the hydrodynamic properties of the mixer. A high nickel extraction efficiency (99.9%) was achieved using a countercurrent three-stage extraction process, while the most concentrated nickel sulfate solution (0.49
kmol/m
3) was obtained with the stripping efficiency of 98.4% in a countercurrent two-stage stripping. This continuous extraction–stripping technique is expected to be effective for recycling nickel from the spent baths.
Various sample preparation methods have been proposed for X-ray fluorescence analysis of mineral components in a liquid. Among them, the dry spot method is widely used; however, the issue is that the ...prepared dried residue is non-uniform. We developed nanoimprint films using the thermal nanoimprint method. A uniform and thin dry residue was prepared using the nanoimprint film. The thin film fundamental parameter method, a quantitative analysis method used in X-ray fluorescence analysis, was applied to dried residues to analyze their content. As a result, the analysis value was found to be close to the authentication and inductively coupled plasma atomic emission spectromy analysis values.
Display omitted
•A parallel cross pattern was formed on a polymer film for liquid sample preparation.•The nanoimprint film produces a thin and uniform dried residue.•Its content is calculated by EDXRF quantitative analysis using thin film FP method.•The analysis value was close to the authentication and ICP-AES analysis values.
Resonant DC-DC Converter With Class-E Oscillator Hase, H.; Sekiya, H.; Jianming Lu ...
IEEE transactions on circuits and systems. I, Regular papers,
09/2006, Letnik:
53, Številka:
9
Journal Article
Recenzirano
This paper presents a new free-running-oscillation resonant DC-DC converter with the Class-E oscillator and the Class-E rectifier, along with its design procedure and design curves for any ...conditions. The proposed converter is a free-running-oscillation system and has no gate-drive circuit to drive the MOSFET. Therefore, the structure of the proposed converter is simpler than that of class E 2 dc-dc converter. The proposed converter is suitable for a constant voltage and constant power operation under the fixed designed condition. The proposed converter has the ability to achieve a high power-conversion efficiency and low noises under high-frequency operation because of Class-E switching at both the oscillator and the rectifier. We investigate operations of the proposed converter by circuit experiments and show the validity of the design curves. This paper denotes two experimental results. One achieves 79.3% power-conversion efficiency under 1.54-W output power at an operating frequency 2.00 MHz. The other does 80.5% under 1.60-W output power at an operating frequency 1.98 MHz
In this paper, a phase control scheme for Class-DE-E dc-dc converter is proposed and its performance is clarified. The proposed circuit is composed of phase-controlled Class-DE inverter and Class-E ...rectifier. The proposed circuit achieves the fixed frequency control without frequency harmonics lower than the switching frequency. Moreover, it is possible to achieve the continuous control in a wide range of the line and load variations. The output voltage decreases in proportion to the increase of the phase shift. The proposed converter keeps the advantages of Class-DE-E dc-dc converter, namely, a high power conversion efficiency under a high-frequency operation and low switch-voltage stress. Especially, high power conversion efficiency can be kept for narrow range control. We present numerical calculations for the design and the numerical analyses to clarify the characteristics of the proposed control. By carrying out circuit experiments, we show a quantitative similarity between the numerical predictions and the experimental results. In our experiments, the measured efficiency is over 84% with 2.5 W output power for 1.0-MHz operating frequency at the nominal operation. Moreover, the output voltage is regulated from 100% to 39%, keeping over 57% power conversion efficiency by using the proposed control scheme.
FM/PWM control scheme in class DE inverter Sekiya, H.; Koizumi, H.; Mori, S. ...
IEEE transactions on circuits and systems. I, Regular papers,
07/2004, Letnik:
51, Številka:
7
Journal Article
Recenzirano
This paper presents a new control scheme for a Class DE inverter, that is, frequency modulation/pulsewidth modulation (FM/PWM) control. Further, the FM/PWM controlled Class DE inverter is analyzed ...and we clarify performance characteristics. Since the FM/PWM controlled inverter has two control parameters, namely, the switching frequency and the switch-on duty ratio, it has one more degree of freedom for the control than the inverter with the conventional control scheme. The increased degree of freedom is used to minimize the switching losses. Therefore, it is possible to control the output power with high power-conversion efficiency for wide-range control. Carrying out the circuit experiments, we confirm that the experimental results agree well with the theoretical predictions quantitatively. For example, the proposed controlled inverter can control the output voltage from 56% to 191% of the optimum one, which is designed for 1.8 W at 1.0 MHz, with maintaining over 90% power-conversion efficiency.
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