Experimental review of an improving system on wireless power transfer via auto tuning of frequency

Wireless power transfer for electric vehicles is focused because these vehicles cannot run long distance without frequently charging. If these vehicles are charged from outside wirelessly, for example an alternating current (AC) power supply is embed under road, the problem is going to be solved. However, efficiency of wireless power transfer depends on various factors, therefore many contrivances should be considered to realize optimal transfer. In this paper, we focused on frequency of inverter, and created auto tuning system of it in response to the distance of inductors. On this system, frequency was modified automatically by a microcontroller and sensor at the same time position of a load changed. Finally, we confirmed that voltage of light emitting diode (LED) was improved by utilizing our system compared with non-tuning frequency

In-Orbit Demonstration of Propellant-Less Formation Flight with Momentum Exchange of Jointed Multiple CubeSats in the MAGNARO Mission

Recently, small satellites such as CubeSats have been applied to a variety of missions such as scientific observations and remote sensing. One of attractive applications that can be relatively easily achieved by small satellites are multi-satellite missions such as formation flight and constellation. As a new method to realize these multi-satellite missions, we propose a method to separate jointed multiple satellite magnetically to generate ΔV without thrusters. To demonstrate the proposed method, we are developing a 3U sized CubeSat called MAGNARO (MAGnetically separating NAnosatellite with Rotation for Orbit control)

Decadal–centennial-scale solar-linked climate variations and millennial-scale internal oscillations during the Early Cretaceous

Understanding climate variability and stability under extremely warm ‘greenhouse’ conditions in the past is essential for future climate predictions. However, information on millennial-scale (and shorter) climate variability during such periods is scarce, owing to a lack of suitable high-resolution, deep-time archives. Here we present a continuous record of decadal- to orbital-scale continental climate variability from annually laminated lacustrine deposits formed during the late Early Cretaceous (123–120 Ma: late Barremian–early Aptian) in southeastern Mongolia. Inter-annual changes in lake algal productivity for a 1091-year interval reveal a pronounced solar influence on decadal- to centennial-scale climatic variations (including the ~ 11-year Schwabe cycle). Decadally-resolved Ca/Ti ratios (proxy for evaporation/precipitation changes) for a ~ 355-kyr long interval further indicate millennial-scale (~ 1000–2000-yr) extreme drought events in inner-continental areas of mid-latitude palaeo-Asia during the Cretaceous. Millennial-scale oscillations in Ca/Ti ratio show distinct amplitude modulation (AM) induced by the precession, obliquity and short eccentricity cycles. Similar millennial-scale AM by Milankovitch cycle band was also previously observed in the abrupt climatic oscillations (known as Dansgaard–Oeschger events) in the ‘intermediate glacial’ state of the late Pleistocene, and in their potential analogues in the Jurassic ‘greenhouse’. Our findings indicate that external solar activity forcing was effective on decadal–centennial timescales, whilst the millennial-scale variations were likely amplified by internal process such as changes in deep-water formation strength, even during the Cretaceous ‘greenhouse’ period

Efficient wireless power transfer for a moving electric vehicle by digital control of frequency

Recently, demand for electric vehicles has been increasing as a countermeasure against global warming, but they currently face many problems compared to gasoline-powered vehicles. For example, charging takes time, and there are few places where electric vehicles can be charged. If AC power supplies that can transfer energy to electric vehicles wirelessly exist under the lanes where electric vehicles drive, the cruising range will be increased. In this study, assuming wireless power transfer to a moving electric vehicle, an experiment was conducted to light up a light-emitting diode (LED) on a moving electric model car. To improve the efficiency of transfer, the optimal frequency for the position of the electric model car was calculated, and the value was fed back to the power supply to adjust the frequency in real time

Development and validation of SSR markers for the plant-parasitic nematode Subanguina moxae using genome assembly of Illumina pair-end reads

WOS: 000355666300002Subanguina moxae, belonging to the subfamily Anguininae, is an obligate parasite of Artemisia plants, which are widely used as cooking herbs and in traditional medicine in East Asia. Because the nematode is distributed throughout East Russia and East Asia, there is concern about the potential for significant damage to commercial farming; however, details about its biology remain unclear. To investigate the genetic diversity of S. moxae, we developed 2243 simple sequence repeat (SSR) markers using Illumina short reads of the genomic DNA. We validated 100 randomly selected markers indicating their robustness and examined polymorphisms among nematode populations sampled from four different locations in Japan. These SSR markers will be a useful tool for understanding the population structure and transmission patterns of this parasitic nematode.Japan Society for the Promotion of Science (JSPS) KAKENHIMinistry of Education, Culture, Sports, Science and Technology, Japan (MEXT)Japan Society for the Promotion of ScienceGrants-in-Aid for Scientific Research (KAKENHI) [24780044, 26292178]The authors thank Mitsuteru Akiba for technical assistance. This work was supported in part by the Japan Society for the Promotion of Science (JSPS) KAKENHI (Grant Nos. 24780044 and 26292178)