There are some limitations when we apply conventional methods to analyze the massive amounts of seismic data acquired with high-density spatial sampling since processors usually obtain the properties of raw data from ...There are some limitations when we apply conventional methods to analyze the massive amounts of seismic data acquired with high-density spatial sampling since processors usually obtain the properties of raw data from common shot gathers or other datasets located at certain points or along lines. We propose a novel method in this paper to observe seismic data on time slices from spatial subsets. The composition of a spatial subset and the unique character of orthogonal or oblique subsets are described and pre-stack subsets are shown by 3D visualization. In seismic data processing, spatial subsets can be used for the following aspects： （1） to check the trace distribution uniformity and regularity; （2） to observe the main features of ground-roll and linear noise; （3） to find abnormal traces from slices of datasets; and （4） to QC the results of pre-stack noise attenuation. The field data application shows that seismic data analysis in spatial subsets is an effective method that may lead to a better discrimination among various wavefields and help us obtain more information.展开更多
The structural and electronic properties of bulk and (001) plane of TiC were investigated by the first-principles total-energy pseudopotential method based on density functional theory.The calculated bulk properties i...The structural and electronic properties of bulk and (001) plane of TiC were investigated by the first-principles total-energy pseudopotential method based on density functional theory.The calculated bulk properties indicate that bonding nature in TiC is a combination of ionicity,covalency and metallicity,in which the Ti-C covalent bonding is the predominate one.The calculated results of structural relaxation and surface energy for TiC(001) slab indicate that slab with 7 layers shows bulk-like characteristic interiors,and the changes of slab occur on the outmost three layers,which shows that the relaxation only influences the top three layers.Meanwhile,the strong Ti-C covalent bonding can be found in the distribution of charge density on the (110) and (001) planes.Ti-C covalent bonding is enhanced by the charge depletion and accumulation in the vacuum and the interlayer region between top two atomic layers.展开更多
This study was conducted on the spatial distribution characteristics of surface tidal currents in the southwestern Taiwan Strait based on the quasi-harmonic analysis of current data obtained by two high frequency surf...This study was conducted on the spatial distribution characteristics of surface tidal currents in the southwestern Taiwan Strait based on the quasi-harmonic analysis of current data obtained by two high frequency surface wave radar(HFSWR) systems. The analysis shows that the tidal current pattern in the southwestern Taiwan Strait is primarily semi-diurnal and influenced significantly by shallow water constituents. The spatial distribution of tidal current ellipses of M2 is probably affected by the interaction between two different systems of tide wave, one from the northern mouth of Taiwan Strait and the other from the Bashi Channel. The directions of the major axes of M2 tidal current ellipses coincide roughly with the axis of the Taiwan Strait. The spatial distribution of the magnitudes of the probable maximum current velocity(PMCS) shows gradual increase of the velocity from northeast to southwest, which is in accordance with the spatial distribution of the measured maximum current velocity(MMCS). The directions of the residual currents are in accordance with the direction of the prevailing monsoon wind at the Taiwan Strait and the direction of the Taiwan warm current during summer. The bathymetry also shows a significant effect on the spatial distribution characteristics of tidal currents.展开更多
The influence of summer monsoon on tropical cyclone (TC) genesis over the Bay of Bengal (BoB) is explored using an empirical genesis potential (GP) index. The annual cycle of cyclogenesis frequency over the BoB shows ...The influence of summer monsoon on tropical cyclone (TC) genesis over the Bay of Bengal (BoB) is explored using an empirical genesis potential (GP) index. The annual cycle of cyclogenesis frequency over the BoB shows an asymmetric bimodal pattern with the maximum genesis number appearing in late October and the second largest in early May. The two peaks correspond to the withdrawal and onset of the BoB summer monsoon, respectively. The semimonthly GP index calculated without TC days over the BoB is consistent with TC genesis frequency, indicating that the index captures the monsoon-induced changes in the environment that are responsible for the seasonal variation of TC genesis frequency. Of the four environmental variables (i.e., low-level vorticity, mid-level relative humidity, potential intensity, and vertical wind shear) that enter into the GP index, the potential intensity makes the largest contribution to the bimodal distribution, followed by vertical wind shear due to small wind speed during the summer monsoon onset and withdrawal. The difference in TC genesis frequency between autumn and late spring is mainly owing to the relative humid-ity difference because a divergence (convergence) of horizontal moisture flux associated with cold dry northerlies (warm wet wester-lies) dominates the BoB in late spring (autumn).展开更多
Latest advances in network sensor technology and state of the art of mobile robotics and artificial intelligence research can be applied to develop autonomous and distributed monitoring systems. Intelligent Space （iS...Latest advances in network sensor technology and state of the art of mobile robotics and artificial intelligence research can be applied to develop autonomous and distributed monitoring systems. Intelligent Space （iSpace） is an environmental system, which is able to support human in informative and physical ways. iSpace observing the space with distributed sensors, extracts useful information from the obtained data and provides various services to users. This means that essential functions of iSpace are ＂observation＂, ＂recognition＂ and ＂actuation.＂ In this paper, we focus on the observation function of iSpace. And we describe observation systems to get information of both human and mobile agents in the space to show new results.展开更多
Objective: To investigate the feasibility of intra-operative radiation therapy (IORT) in hepato-cellular carcinoma (HCC). Methods: Based on the dosage distribution of tumor and adjacent sensitive organs, and dose-volu...Objective: To investigate the feasibility of intra-operative radiation therapy (IORT) in hepato-cellular carcinoma (HCC). Methods: Based on the dosage distribution of tumor and adjacent sensitive organs, and dose-volume histogram (DVH), Topslane three-dimensional therapy plan was used to compare IORT and three-dimensional conformal radiation therapy (3D-CRT) in 12 cases of HCC. Results: Taking the center of tumors as the isodose center, the V90 (volume of 90% dose distribution) of IORT was significantly better than that of 3D-CRT, and median absorbed doses of normal organs in IORT was significantly lower than that in 3D-CRT. Conclusion: The V90 of IORT is better than that of 3D-CRT in HCC, and neighboring sensitive organs were effectively protected by IORT. The tumors absorbed dose and local control rate are improved in IORT.展开更多
Drifting can be an effective way for aquatic organisms to disperse and colonise new areas. Increasing connectivity between European large rivers facilitates invasion by drifting aquatic macroinvertebrates. The present...Drifting can be an effective way for aquatic organisms to disperse and colonise new areas. Increasing connectivity between European large rivers facilitates invasion by drifting aquatic macroinvertebrates. The present study shows that high abundances of invasive species drift in the headstream of the river Rhine. Dikerogammarus villosus and Chelicorophium cur- vispinum represented up to 90% of the total of drifting macroinvertebrates. Drift activity shows seasonal and diel patterns. Most species started drifting in spring and were most abundant in the water column during the summer period. Drift activity was very low during the winter period. Diel patterns were apparent; most species, including D. villosus, drifted during the night. Drifting macroinvertebrates colonised stony substrate directly from the water column. D. villosus generally colonised the substrate at night, while higher numbers of C. curvispinum colonised the substrate during the day. It is very likely that drifting functions as a disper- sal mechanism for crustacean invaders. Once waterways are connected, these species are no longer necessarily dependent on dispersal vectors other than drift for extending their distribution range展开更多
A study of[S Ⅲ]λλ9096,9532 emitters at z=1.34 and 1.23 is presented using our deep narrow-band H2S 1(centered at 2.13μm)imaging survey of the Extended Chandra Deep Field South(ECDFS).We combine our data with multi...A study of[S Ⅲ]λλ9096,9532 emitters at z=1.34 and 1.23 is presented using our deep narrow-band H2S 1(centered at 2.13μm)imaging survey of the Extended Chandra Deep Field South(ECDFS).We combine our data with multi-wavelength data of ECDFS to build up spectral energy distributions(SEDs)from the U to the Ks-band for emitter candidates selected with strong excess in H2S 1 Ks and derive photometric redshifts,line luminosities,stellar masses and extinction.A sample of 14[S Ⅲ]emitters are identified with H2S 1<22.8 and Ks<24.8(AB)over 381 arcmin2area,having[S Ⅲ]line luminosity L[S Ⅲ]=~1041.5 42.6erg s 1.None of the[S Ⅲ]emitters is found to have X-ray counterpart in the deepest Chandra 4 Ms observation,suggesting that they are unlikely powered by AGNs.The HST/ACS F606W and HST/WFC3 F160W images show their rest-frame UV and optical morphologies.About half of the[S Ⅲ]emitters are mergers and at least one third are disk-type galaxies.Nearly all[S Ⅲ]emitters exhibit a prominent Balmer break in their SEDs,indicating the presence of a significant post-starburst component.Taken together,our results imply that both shock heating in post-starburst and photoionization caused by young massive stars are likely to excite strong[S Ⅲ]emission lines.We conclude that the[S Ⅲ]emitters in our sample are dominated by star-forming galaxies(SFGs)with stellar mass 8.7<log(M/M⊙)<9.9.展开更多
文摘There are some limitations when we apply conventional methods to analyze the massive amounts of seismic data acquired with high-density spatial sampling since processors usually obtain the properties of raw data from common shot gathers or other datasets located at certain points or along lines. We propose a novel method in this paper to observe seismic data on time slices from spatial subsets. The composition of a spatial subset and the unique character of orthogonal or oblique subsets are described and pre-stack subsets are shown by 3D visualization. In seismic data processing, spatial subsets can be used for the following aspects： （1） to check the trace distribution uniformity and regularity; （2） to observe the main features of ground-roll and linear noise; （3） to find abnormal traces from slices of datasets; and （4） to QC the results of pre-stack noise attenuation. The field data application shows that seismic data analysis in spatial subsets is an effective method that may lead to a better discrimination among various wavefields and help us obtain more information.
基金Project(200802015) supported by Post-doctoral Foundation of Shandong Province,ChinaProject(50625101) supported by the National Natural Science Foundation for Distinguished Young Scholars of China
文摘The structural and electronic properties of bulk and (001) plane of TiC were investigated by the first-principles total-energy pseudopotential method based on density functional theory.The calculated bulk properties indicate that bonding nature in TiC is a combination of ionicity,covalency and metallicity,in which the Ti-C covalent bonding is the predominate one.The calculated results of structural relaxation and surface energy for TiC(001) slab indicate that slab with 7 layers shows bulk-like characteristic interiors,and the changes of slab occur on the outmost three layers,which shows that the relaxation only influences the top three layers.Meanwhile,the strong Ti-C covalent bonding can be found in the distribution of charge density on the (110) and (001) planes.Ti-C covalent bonding is enhanced by the charge depletion and accumulation in the vacuum and the interlayer region between top two atomic layers.
基金supported by the National High Technology Research and Development Program (‘863’ Program) of China under contract No. 2012AA091701the Fundamental Research Fund for the Central University of China under the contract No. 2012212020211
文摘This study was conducted on the spatial distribution characteristics of surface tidal currents in the southwestern Taiwan Strait based on the quasi-harmonic analysis of current data obtained by two high frequency surface wave radar(HFSWR) systems. The analysis shows that the tidal current pattern in the southwestern Taiwan Strait is primarily semi-diurnal and influenced significantly by shallow water constituents. The spatial distribution of tidal current ellipses of M2 is probably affected by the interaction between two different systems of tide wave, one from the northern mouth of Taiwan Strait and the other from the Bashi Channel. The directions of the major axes of M2 tidal current ellipses coincide roughly with the axis of the Taiwan Strait. The spatial distribution of the magnitudes of the probable maximum current velocity(PMCS) shows gradual increase of the velocity from northeast to southwest, which is in accordance with the spatial distribution of the measured maximum current velocity(MMCS). The directions of the residual currents are in accordance with the direction of the prevailing monsoon wind at the Taiwan Strait and the direction of the Taiwan warm current during summer. The bathymetry also shows a significant effect on the spatial distribution characteristics of tidal currents.
基金supported by the National Basic Research Program of China(973Program:2012CB955604)National Natural Science Foundation of China(No.40975038,40830106)the CMA Program(GYHY200906008)
文摘The influence of summer monsoon on tropical cyclone (TC) genesis over the Bay of Bengal (BoB) is explored using an empirical genesis potential (GP) index. The annual cycle of cyclogenesis frequency over the BoB shows an asymmetric bimodal pattern with the maximum genesis number appearing in late October and the second largest in early May. The two peaks correspond to the withdrawal and onset of the BoB summer monsoon, respectively. The semimonthly GP index calculated without TC days over the BoB is consistent with TC genesis frequency, indicating that the index captures the monsoon-induced changes in the environment that are responsible for the seasonal variation of TC genesis frequency. Of the four environmental variables (i.e., low-level vorticity, mid-level relative humidity, potential intensity, and vertical wind shear) that enter into the GP index, the potential intensity makes the largest contribution to the bimodal distribution, followed by vertical wind shear due to small wind speed during the summer monsoon onset and withdrawal. The difference in TC genesis frequency between autumn and late spring is mainly owing to the relative humid-ity difference because a divergence (convergence) of horizontal moisture flux associated with cold dry northerlies (warm wet wester-lies) dominates the BoB in late spring (autumn).
文摘Latest advances in network sensor technology and state of the art of mobile robotics and artificial intelligence research can be applied to develop autonomous and distributed monitoring systems. Intelligent Space （iSpace） is an environmental system, which is able to support human in informative and physical ways. iSpace observing the space with distributed sensors, extracts useful information from the obtained data and provides various services to users. This means that essential functions of iSpace are ＂observation＂, ＂recognition＂ and ＂actuation.＂ In this paper, we focus on the observation function of iSpace. And we describe observation systems to get information of both human and mobile agents in the space to show new results.
基金Supported by the Science and Technology Research Foundation of Shaanxi Province (2005k09-G5)
文摘Objective: To investigate the feasibility of intra-operative radiation therapy (IORT) in hepato-cellular carcinoma (HCC). Methods: Based on the dosage distribution of tumor and adjacent sensitive organs, and dose-volume histogram (DVH), Topslane three-dimensional therapy plan was used to compare IORT and three-dimensional conformal radiation therapy (3D-CRT) in 12 cases of HCC. Results: Taking the center of tumors as the isodose center, the V90 (volume of 90% dose distribution) of IORT was significantly better than that of 3D-CRT, and median absorbed doses of normal organs in IORT was significantly lower than that in 3D-CRT. Conclusion: The V90 of IORT is better than that of 3D-CRT in HCC, and neighboring sensitive organs were effectively protected by IORT. The tumors absorbed dose and local control rate are improved in IORT.
文摘Drifting can be an effective way for aquatic organisms to disperse and colonise new areas. Increasing connectivity between European large rivers facilitates invasion by drifting aquatic macroinvertebrates. The present study shows that high abundances of invasive species drift in the headstream of the river Rhine. Dikerogammarus villosus and Chelicorophium cur- vispinum represented up to 90% of the total of drifting macroinvertebrates. Drift activity shows seasonal and diel patterns. Most species started drifting in spring and were most abundant in the water column during the summer period. Drift activity was very low during the winter period. Diel patterns were apparent; most species, including D. villosus, drifted during the night. Drifting macroinvertebrates colonised stony substrate directly from the water column. D. villosus generally colonised the substrate at night, while higher numbers of C. curvispinum colonised the substrate during the day. It is very likely that drifting functions as a disper- sal mechanism for crustacean invaders. Once waterways are connected, these species are no longer necessarily dependent on dispersal vectors other than drift for extending their distribution range
基金This research uses data obtained through the Telescope Access Program(TAP),which is funded by the National Astronomical Observatories and the Special Fund for Astronomy from the Ministry of Financesupported by the National Basic Research Program of China(GrantNo.2013CB834900)the National Natural Science Foundation of China(Grant No.11063002)
文摘A study of[S Ⅲ]λλ9096,9532 emitters at z=1.34 and 1.23 is presented using our deep narrow-band H2S 1(centered at 2.13μm)imaging survey of the Extended Chandra Deep Field South(ECDFS).We combine our data with multi-wavelength data of ECDFS to build up spectral energy distributions(SEDs)from the U to the Ks-band for emitter candidates selected with strong excess in H2S 1 Ks and derive photometric redshifts,line luminosities,stellar masses and extinction.A sample of 14[S Ⅲ]emitters are identified with H2S 1<22.8 and Ks<24.8(AB)over 381 arcmin2area,having[S Ⅲ]line luminosity L[S Ⅲ]=~1041.5 42.6erg s 1.None of the[S Ⅲ]emitters is found to have X-ray counterpart in the deepest Chandra 4 Ms observation,suggesting that they are unlikely powered by AGNs.The HST/ACS F606W and HST/WFC3 F160W images show their rest-frame UV and optical morphologies.About half of the[S Ⅲ]emitters are mergers and at least one third are disk-type galaxies.Nearly all[S Ⅲ]emitters exhibit a prominent Balmer break in their SEDs,indicating the presence of a significant post-starburst component.Taken together,our results imply that both shock heating in post-starburst and photoionization caused by young massive stars are likely to excite strong[S Ⅲ]emission lines.We conclude that the[S Ⅲ]emitters in our sample are dominated by star-forming galaxies(SFGs)with stellar mass 8.7<log(M/M⊙)<9.9.
