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521.
Approximately ten years have passed since Globally Important Agricultural Heritage Systems (GIAHS) was introduced to Japan in 2011, with 11 GIAHS sites designated so far. The Japan Nationally Important Agricultural Heritage Systems (J-NIAHS), which considers resilience, multi-stakeholder participation and sixth industrialization, was subsequently established in 2016, and has designated 15 J-NIAHS sites. GIAHS sites can be classified into three major types: Landscape, farming method, and genetic resource conservation types, and most Japanese GIAHS sites are of the landscape type. Since there is almost no national subsidy for GIAHS or J-NIAHS, designated sites are expected to secure funding for conservation from their own efforts. For this reason, a voluntary network of the Japanese GIAHS sites has been active in promoting cooperation on GIAHS conservation. The priorities of the Japanese GIAHS have focused on raising public awareness about GIAHS and J-NIAHS, improving livelihoods, as well as fostering the international exchange of experience and knowledge regarding Agricultural Heritage Systems, especially among Japan, China and Korea. 相似文献
522.
The Influence Of Urban Canopy Configuration On Urban Albedo 总被引:6,自引:0,他引:6
Akira Kondo Megumi Ueno Akikazu Kaga Katsuhito Yamaguchi 《Boundary-Layer Meteorology》2001,100(2):225-242
We propose a calculation method for shortwave radiation flux and longwave radiation flux within the urban canopy and investigate the influence of urban canopy configuration on net radiation flux. In the assumed urban configuration, buildings of equal size are arranged in a regular lattice within the urban canopy. The net shortwave radiation flux and longwave radiation flux within the urban canopy were calculated by the photon tracking method based on the Monte Carlo method. The albedo value obtained by this method shows close agreement with experimental data, and the average sky view factor shows almost perfect agreement with the theoretical value. Moreover, we calculated the urban albedo for the urban canopy configuration including roads and building height distribution.%Moreover, we calculated net radiation within the urban canopy in %consideration of roads and building height distribution.We found that the sky view factor of the ground surface is high when building coverage is low, building height is low, open space by roads exists, and building height is non-uniform. Moreover, we found that the albedo value is high when building height is small, open space by roads is wide, and building height is uniform. The albedo value was found to vary in a complicated manner with change in building coverage. 相似文献
523.
High‐pressure polymorphs in Yamato‐790729 L6 chondrite and their significance for collisional conditions 下载免费PDF全文
Yukako Kato Toshimori Sekine Masahiko Kayama Masaaki Miyahara Akira Yamaguchi 《Meteoritics & planetary science》2017,52(12):2570-2585
Shock pressure recorded in Yamato (Y)‐790729, classified as L6 type ordinary chondrite, was evaluated based on high‐pressure polymorph assemblages and cathodoluminescence (CL) spectra of maskelynite. The host‐rock of Y‐790729 consists mainly of olivine, low‐Ca pyroxene, plagioclase, metallic Fe‐Ni, and iron‐sulfide with minor amounts of phosphate and chromite. A shock‐melt vein was observed in the hostrock. Ringwoodite, majorite, akimotoite, lingunite, tuite, and xieite occurred in and around the shock‐melt vein. The shock pressure in the shock‐melt vein is about 14–23 GPa based on the phase equilibrium diagrams of high‐pressure polymorphs. Some plagioclase portions in the host‐rock occurred as maskelynite. Sixteen different CL spectra of maskelynite portions were deconvolved using three assigned emission components (centered at 2.95, 3.26, and 3.88 eV). The intensity of emission component at 2.95 eV was selected as a calibrated barometer to estimate shock pressure, and the results indicate pressures of about 11–19 GPa. The difference in pressure between the shock‐melt vein and host‐rock might suggest heterogeneous shock conditions. Assuming an average shock pressure of 18 GPa, the impact velocity of the parent‐body of Y‐790729 is calculated to be ~1.90 km s?1. The parent‐body would be at least ~10 km in size based on the incoherent formation mechanism of ringwoodite in Y‐790729. 相似文献
524.
525.
Pankajakshan Thadathil Akira Shikauchi Yasuhiro Sugimori Masahisa Kubota 《Journal of Oceanography》1993,49(5):551-558
Ten-day mean surface level air-temperature from SSMI precipitable water (SSMI-T
a
) has been derived and compared with the temperature from two ocean data buoys (Buoy-T
a
) of Japan Meteorological Agency (JMA) for a period of six months (July–December, 1988). Statistical relations between air-temperature and mixing ratio, using data from ocean data buoys are used to derive air-temperature from mixing ratio, obtained from SSMI precipitable water. For getting the mixing ratio from precipitable water, regional mixing ratio-precipitable water relations have been used, instead of global relation proposed by Liu (1986). The rms errors (standard deviation of the difference between SSMI-T
a
and Buoy-T
a
) for two buoy locations are found to be 1.15 and 1.12°C, respectively. Surface level temperature for the two buoy locations are also derived using direct regression relation between Buoy-T
a
and precipitable water. The rms errors of the SSMI-T
a
, in this case are found to be reduced to 1.0°C. 相似文献
526.
We investigated the phase difference and the cross correlation coefficient between the band-pass filtered biennial variations of sea surface temperature (SST) and air-sea heat flux estimated by the monthly mean 2°×2° satellite data of Advanced Very High Resolution Radiometer (AVHRR) and Special Sensor Microwave/Imager (SSM/I) from July 1987 to June 1991. Judging from the phase difference, it can be determined whether the biennial variation of SST is controlled by local thermal air-sea interaction or oceanic processes of horizontal transport. When the local air-sea heat flux controls the biennial variation of SST, the phase of SST advances /2 (6 months) against that of the air-sea heat flux. In contrast, when the biennial variation of SST is controlled by the oceanic process, the phase difference between the SST and the air-sea heat flux becomes 0 or (12 months). In this case, two types of the phase differences are determined, depending on which variability of SST and air-sea heat flux is larger. The close thermal air-sea interaction is noticeable in the tropics and in the western boundary current region. The phase difference of /2 appears mainly in the north Pacific, the southeast Indian Ocean, and the western tropical Pacific; zero in the eastern tropical Pacific and the northeast and equatorial Atlantic; and that of in the central equatorial Pacific and north of the intertropical convergence zone (ITCZ) of the Atlantic. Phase differences of 0, , or /2 are possible in the western boundary current regions. This fact indicates that each current plays a different role to the biennial variation of SST. It is inferred that SST anomalies in the tropics are mutually correlated, and the process in which marked SST anomalies in the tropics are transferred to the remote area was probed. In the equatorial Pacific, the SST anomaly is transferred by the long planetary wave. On the other hand, it is found from the phase relationship and the horizontal correlation of SST that the SST anomaly in the central and western equatorial Pacific is connected through atmospheric mediation. It is suggested that the biennial variation of SST in the eastern Indian Ocean is affected by heat transport due to the Indonesian throughflow from the western tropical Pacific. It is found that the mentioned pattern of the interannual variation of SST in the tropical Atlantic as a dipole is not tenable. 相似文献
527.
Hayao Morinaga Hiroo Inokuchi Hideki Yamashita Akira Ono Takashi Inada 《Geoarchaeology》1999,14(5):377-399
We present a methodological approach to detect heated soil on ancient sites, using magnetic measurements. The method is based on changes in magnetic signals of soil by heating. The following three types of soil were used for testing the method: silty soil (SS), weathered volcanic ash (WVA, = loam) and fairly fresh volcanic ash (VA) called Odori tephra. On heating above 250–600°C, the magnetic susceptibility and remanent magnetization intensity increased for the SS and WVA samples, reflecting chemical alteration of magnetic minerals (from goethites to magnetites through hematites). The VA sample showed no susceptibility change suggesting the absence of goethites within it. On heating below 250°C, only the intensities of all the samples increased. This is possibly due to acquisition of thermal remanent magnetization. The largest change of the magnetic signals was identified for the SS sample and the smallest one was seen for the VA sample. Therefore, the in situ susceptibility measurement, which is the nondestructive and indirect method, seems to be effective to detect heated soil for sites of aqueous deposits as the SS. On the other hand, for sites of aeolian deposits as the WVA (loam) and VA, the intensity measurement of collected soils seems to be the most reliable method to detect evidence of heating. The degree of the magnetic stability (coercivity) against progressive alternating-field demagnetization was also an important parameter, indicating whether the investigated soils were heated or unheated. © 1999 John Wiley & Sons, Inc. 相似文献