136 resultados para Scatter plot


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对最佳鉴别矢量的求解方法进行了研究,根据矩阵的分块理论和优化理论,在一定的条件下,从理论上得到类间散布矩阵和总体散布矩阵的一种简洁表示方法,提出了求解最佳鉴别矢量的一种新算法,该算法的优点是计算量明显减少。ORL人脸数据库的数值实验,验证了上述论断的正确性。实验结果表明,虽然识别率与分块维数之间存在非线性关系,但可以通过选择适当的分块维数来获得较高的识别率。类间散布矩阵和总体散布矩阵的一种简洁表示方法适合于一切使用Fisher鉴别准则的模式识别问题。

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The most widespread rock associations in the Western Block of North China Craton are khondalites distributed mainly in Jining, Liangcheng and Datong. A large quantitiy of garnet-bearing granites are contained in the khondalites. A great deal of research has been carried out on them by previous researchers. Studies of these garnet-bearing granites consist essentially of structural characteristics, petrography and geochemistry, and finally geochronological determinations. Summing up these researches, it will not be difficult to see that all of these authors have regarded these large numbers of garnets (up to 20%) contained in granites as crystallized products from magmas, but they have not proved this from petrological perspective. Theoretically, there are possibly three kinds of petrogenesis as to these garnets. The first one is that they have been transferred to the granites from khondalites by melt when anatexis happened to khondalites, and they, in essence, are residual metamorphic garnets; The second one is that when the khondalites were being melted, these garnets were produced from biotite dehydration melting, and the newly formed garnets intruded together with the melt and eventually molded the garnet-bearing granites. Garnets of this possible kind either showed independent crystals, or garnets from khondalites took place secondary growth under favorable temperature and pressure conditions for their crystallization; The last possibility is that these garnets were crystallized from magmas in which suitable pressure, temperature and composition were available. These garnets, generally, should be fine-grained. The aim of this study is, through examining the mineral chemistry of the garnets and the whole rock chemistry, to ascertain under which kind of mechanism, in the world, did these garnets form? Besides, we try to calculate the temperatures under which khondalites began melting and reactions of the garnets and the cooled melts happened by garnet-biotite thermometry. The whole rock chemistry analyses of the garnet-bearing granites tell us that all the samples are strongly peraluminous (A/CNK greater than 1.1) on the A/NK vs. A/CNK plot. On the SiO2-K2O plot, the granites are mainly constrained to be high-K calc-alkaline and calc-alkaline series, consistent with previous researches. On the ACF((Al2O3-Na2O-K2O)-FeO(T)-CaO) discrimination plot, all the six garnet-bearing granite samples drop into the area of S-type granites. The relationship between CaO/Na2O and SiO2 shows that the overwhelming majority of garnet-bearing granites have a CaO/Na2O value over 0.3, revealing that they probably come from metagreywacke precursors or mediate-felsic orthogeneisses compositionally similar to them. Detailed EPMA analyses conducted on the garnets contained in the garnet-bearing granites show that all the garnets are dominated by almandine and pyrope, which occupy 92-96% (Weight Percentage) of each garnet analyzed, typical of granulite facies. Their chemical composition is entirely different from those crystallized in magmas, but extremely similar to those of typical granulite facies metapelites in khondalites and typical granulites, indicating all the garnets to be metamorphogenic. In addition, REEs distribution patterns of the garnets are totally different from typical biotite granites and peraluminous granites. In other words, both LREE and HREE of our garnets are evidently lower than those from these two kinds of rocks. Moreover, compared to the REE pattern of the garnets from typical amphibolites, LREE content of our garnets is obviously higher and HREE content is a little lower. However, REE patterns of our garnets are completely in harmony with those of garnets from typical granulites. So, the REE patterns of garnets, again, prove that all the garnets we studied are metamorphogenic. Biotites appear in two forms, being as inclusions in the garnet and as selvages immediately adjacent to the garnet, respectively. Two reactions and their corresponding temperatures, with the help of petrography and Garnet-Biotite geothermometers, could be obtained, which are Bt+ Pl+ Qtz→Kfs+ Opx+ Grt+ melt as positive reaction and Kfs+ Grt+ melt→Bt+ Pl+ Qtz as reverse reaction, respectively. Summing up the discussion above, we declare that the garnet-bearing granites distributed in the Western Block of North China Craton are the mixture of melts and restites resulted from biotite dehydration melting. The garnets contained in the restites are the products from biotite dehydration melting and restites from the khondalites, respectively.

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The Tianshan Mountains is located about 1000-2000 km north of the India-Asia suture and is the most outstanding topography in central Asia, with transmeridional length of nearly 2500 km, north-southern wideness of ~ 300-500 km, peaks exceeding 7000 m above sea level (asl.), and average altitude of over 4000 m asl. Much of the modern relief of the Tianshan Range is a result of contraction driven by the collision of the India subcontinent with the southern margin of Asia, which began in early Tertiary and continues today. Understanding where, when and how the deformation of the Tianshan Mountains occurred is essential to decipher the mechanism of intracontinental tectonics, the process of foreland basin evolution and mountain building, and the history of climate change in central Asia. In order to better constrain the Cenozoic building history of the Tianshan Mountains and the climate change in the southern margin of the Junggar Basin, we carried out multiple studies of magnetostratigraphy, sedimentology, and stable isotopes of paleosol carbonate at the Jingou River section, which is located at the Huoerguosi anticline, the westernest one of the second folds and thrust faults zone in the northern piedmont of the Tianshan Mountains. The Jingou River section with a thickness of about 4160 m is continuous in deposits according to the observed gradual change in sedimentary environments and can be divided into five formations: Anjihaihe, Shawan, Taxihe, Dushanzi and Xiyu in upward sequence. Characteristic remamences were isolated by progressive thermal demagnetization, generally between 300 and 680℃. A total of 1133 out of 1607 samples yielded well-defined ChRMs and were used to establish the magnetostratigraphic column of a 3270-m-thick section from the exposed base of the Anjihaihe Formation to the middle of the Xiyu Formation. Two vertebrate fossil sites and a good correlation with the CK95 geomagnetic polarity time scale suggest that the section was deposited from ~30.5 to ~4.6 Ma and the age of the top of the Xiyu formation is ~2.6 Ma based on an extrapolation of the sedimentation rates. A plot of magnetostratigraphic age vs. height at the Jingou River section shows that significant increases in sedimentation rates as well as notable changes in depositional environments occurred at ~26-22.5 Ma, ~13-11 Ma and ~7 Ma, which represent the initial uplift of the Tianshan Mountains and two subsequent rapid uplift events. In addition, changes in sedimentation rates display characteristic alternations between increases and decreases, which probably indicate that the uplift of the Tianshan Mountains was episodic. We discussed the history of C4 biomass and climatic conditions in the southern margin of the Junggur Basin using the stable carbon and oxygen isotope composition of paleosol carbonates from the Jingou River section during ~17.5-6.5 Ma. The δ13C values indicate that the proportion of C4 biomass was uniform and moderate (15-20 %) during the interval of ~17.5-6.5 Ma. We proposed three hypotheses for this pattern of C4 biomass: (1) counteraction of two opposed factors (global cooling since ~15 Ma and thereafter increased dry and seasonality in central Asia) controlling the growth of C4 grasses, (2) variability in abundance of C3 grasses relative to C3 trees and shrubs if vegetation had ever changed in ecosystems, and (3) the higher latitude of the studied region. The δ18O values show a stepwise negative trend since ~13 Ma which may be attributed to three factors: (1) the temperature decreasing gradually after the middle Miocene (~15 Ma), (2) the increasing contribution of the moistures carried by the polar air masses from the Arctic Ocean to precipitation, and (3) the gradual retreat westward and disappearance of the Paratethys Ocean. Among them, which one played a more important role will need further study of the paleoclimate in central Asia.

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As a fast and effective method for approximate calculation of seismic numerical simulation, ray tracing method, which has important theory and practical application value, in terms of seismic theory and seismic simulation, inversion, migration, imaging, simplified from seismic theory according to geometric seismic, means that the main energy of seismic wave field propagates along ray paths in condition of high-frequency asymptotic approximation. Calculation of ray paths and traveltimes is one of key steps in seismic simulation, inversion, migration, and imaging. Integrated triangular grids layout on wavefront with wavefront reconstruction ray tracing method, the thesis puts forward wavefront reconstruction ray tracing method based on triangular grids layout on wavefront, achieves accurate and fast calculation of ray paths and traveltimes. This method has stable and reasonable ray distribution, and overcomes problems caused by shadows in conventional ray tracing methods. The application of triangular grids layout on wavefront, keeps all the triangular grids stable, and makes the division of grids and interpolation of a new ray convenient. This technology reduces grids and memory, and then improves calculation efficiency. It enhances calculation accuracy by accurate and effective description and division on wavefront. Ray tracing traveltime table, which shares the character of 2-D or 3-D scatter data, has great amount of data points in process of seismic simulation, inversion, migration, and imaging. Therefore the traveltime table file will be frequently read, and the calculation efficiency is very low. Due to these reasons, reasonable traveltime table compression will be very necessary. This thesis proposes surface fitting and scattered data compression with B-spline function method, applies to 2-D and 3-D traveltime table compression. In order to compress 2-D (3-D) traveltime table, first we need construct a smallest rectangular (cuboidal) region with regular grids to cover all the traveltime data points, through the coordinate range of them in 2-D surface (3-D space). Then the value of finite regular grids, which are stored in memory, can be calculated using least square method. The traveltime table can be decompressed when necessary, according to liner interpolation method of 2-D (3-D) B-spline function. In the above calculation, the coefficient matrix is stored using sparse method and the liner system equations are solved using LU decomposition based on the multi-frontal method according to the sparse character of the least square method matrix. This method is practiced successfully in several models, and the cubic B-spline function can be the best basal function for surface fitting. It make the construction surface smooth, has stable and effective compression with high approximate accuracy using regular grids. In this way, through constructing reasonable regular grids to insure the calculation efficiency and accuracy of compression and surface fitting, we achieved the aim of traveltime table compression. This greatly improves calculation efficiency in process of seismic simulation, inversion, migration, and imaging.

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The long-term variations in the strength of the geomagnetic field provide important constraints on the chemical-physical processes of the Earth’s interior. Especially, the intensity of the geomagnetic field during the Cretaceous normal superchron (CNS) is crucial to understand the geodynamo. But a paucity of paleointensity further limits to obtain essential knowledge interior process in the deep earth. In order to improve the experimental efficiency, this study tried to apply two new rock magnetic methods (FORC diagram and low-temperature demagnetization technique) to determine the paleointensity. First, some problems in the theory and technique in paleointensity experiments were introduced. A combined palaeomagnetic and geochronologic study was further conducted on a basaltic lava sequence at Jianchang in Liaoning Province, northeastern China. Radiometric 40Ar/39Ar dating indicates that the volcanism occurred at about 119 Ma within the marine anomaly C34n in Cretaceous normal superchron (CNS). Rock magnetic investigations show that pseudo-single domain (PSD) titanium-poor titanomagnetite is dominant in the studied lava flows. Both stepwise thermal and alternating field demagnetizations isolate the well-defined normal characteristic remanent magnetization (ChRM) in three independent lava flows with a mean direction of D/I = 6.0/51.9 degree(a95 = 12.3degree). Palaeointensity was determined using the modified Thellier method with systematic partial thermoremanent magnetization (pTRM) checks on total 72 samples, but only 10 samples exhibit ideal linear behavior on the Arai-plot in the temperature interval of 300-560 C and yield an average paleointensity of (25.8+/-1.4)uT. In addition, slopes of the line defined by the initial and the final points on the Arai-plot for the other 18 samples with characteristic PSD features give an average paleointensity estimation value of (24.8+/-1.9)uT. The consistency of these two approaches confidently demonstrates the fidelity of our results. The overall mean field strength determined using both approaches are thus estimated to be (25.2+/-0.7 )uT. This value corresponds to the virtual dipole magnetic moments (VDM) of (4.5+/-0.1)E22 Am^2, which is about half of the value of present field. This finding suggests that palaeointensity just at the onset of the CNS is characterized by a weak magnetic field.

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Increasing attentions have been paid to the subsurface geological storage for CO2 in view of the huge storage capacity of subsurface reservoirs. The basic requirement for subsurface CO2 storage is that the CO2 should be sequestrated as supercritical fluids (physical trapping), which may also interact with ambient reservoir rocks and formation waters, forming new minerals (chemical trapping). In order to the effective, durable and safe storage for CO2, enough storage space and stable sealing caprock with strong sealing capacity are necessitated, in an appropriate geological framework. Up till now, hydrocarbon reservoirs are to the most valid and appropriate CO2 storage container, which is well proven as the favorable compartment with huge storage capacity and sealing condition. The thesis focuses on two principal issues related to the storage and sealing capacity of storage compartment for the Qingshankou and Yaojia formations in the Daqingzijing block, Southern Songliao Basin, which was selected as the pilot well site for CO2-EOR storage. In the operation area, three facies, including deltaic plain, deltaic front and subdeep-deep lake facies associations, are recognized, in which 11 subfacies such as subaqueous distributary channel, river- mouth bar, interdistributary bay, sheet sandbody, crevasse splay and overflooding plain are further identified. These subfacies are the basic genetic units in the reservoir and sealing rocks. These facies further comprise the retrogradational and progradational depositional cycles, which were formed base- level rise and fall, respectively. During the regressive or lake lowstand stage, various sands including some turbidites and fans occurred mostly at the bottom of the hinged slope. During the progradation stage, these sands became smaller in size and episodically stepped backwards upon the slope, with greatly expanded and deeped lake. However, most of Cretaceous strata in the study area, localized in the basin centre under this stage, are mainly composed of grey or grizzly siltstones and grey or dark grey mudstones intercalated with minor fine sandstones and purple mudstones. On the base of borehole and core data, these siltstones are widespread, thin from 10 to 50 m thick, good grain sorting, and have relative mature sedimentary structures with graded bedding and cross- lamination or crossbeds such as ripples, which reflect strong hydrodynamic causes. Due to late diagenesis, pores are not widespread in the reservoirs, especially the first member of Qingshankou formation. There are two types of pores: primary pore and secondary cores. The primary pores include intergranular pores and micropores, and the secondary pores include emposieus and fracture pores. Throat channels related to pores is also small and the radius of throat in the first, second and third member of Qingshankou formation is only 0.757 μm, 0.802 μm and 0.631 μm respectively. In addition, based on analyzing the probability plot according to frequency of occurrence of porosity and permeability, they appear single- peaked distribution, which reflects strong hetero- geneity. All these facts indicate that the conditions of physical property of reservoirs are not better. One reason may be provided to interpret this question is that physical property of reservoirs in the study area is strong controlled by the depositional microfacies. From the statistics, the average porosity and permeability of microfacies such as subaqueous distributary channel, channel mouth bar, turbidites, is more than 9 percent and 1md respectively. On the contrary, the average porosity and permeability of microfacies including sand sheet, flagstone and crevasse splay are less than 9 percent and 0.2md respectively. Basically, different hydrodynamic environment under different microfacies can decide different physical property. According to the reservoir models of the first member of Qingshankou formation in the No. well Hei47 block, the character of sedimentary according to the facies models is accord to regional disposition evolution. Meantime, the parameter models of physical property of reservoir indicate that low porosity and low permeability reservoirs widespread widely in the study area, but the sand reservoirs located in the channels are better than other places and they are the main sand reservoirs. The distribution and sealing ability of fault- fractures and caprock are the key aspects to evaluate the stable conditions of compartments to store CO2 in the study area. Based on the core observation, the fractures widespread in the study area, especially around the wells, and most of them are located in the first and second member of Qingshankou formation, almost very few in the third member of Qingshankou formation and Yaojia formation instead. In addition, analyzing the sealing ability of eleven faults in the three-dimensional area in the study area demonstrates that most of faults have strong sealing ability, especially in the No. well Hei56 and Qing90-27. To some extent, the sealing ability of faults in the No. well Hei49, Qing4-6 and Qing84-29 are worse than others. Besides, the deposition environment of most of formations in the study area belongs to moderately deep and deep lake facies, which undoubtedly take advantage to caprocks composed of mudstones widespread and large scale under this deposition environment. In the study area, these mudstones distribute widely in the third member of Qingshankou formation, Yaojia and Nenjiang formation. The effective thickness of mudstone is nearly ~550m on an average with few or simple faults and fractures. In addition, there are many reservoir beds with widely- developed insulated interbeds consist of mudstones or silty mudstone, which can be the valid barrier to CO2 upper movement or leakage through diffusion, dispersion and convection. Above all, the closed thick mud caprock with underdeveloped fractures and reservoir beds can be taken regard as the favorable caprocks to provide stable conditions to avoid CO2 leakage.

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Neutral winds and electric fields in the ionospheric F layer play important roles in the variations of the ionosphere, and also affect the thermospheric circulation via the close coupling between the ionosphere and the thermosphere. By now, the neutral winds and electric drifts are generally observed with ground-based Fabry-Perot interferometers (FPI) and incoherent scatter radars (ISR), rockets, and satellite-borne instrument. Based on the servo theory, the ionospheric equivalent winds, which include the information of both the neutral winds and electric fields, can be derived from these characteristic parameters observed by ionosondes. This indirect derivation has potential values in climatological researches and space weather forecast. With the data set of the incoherent scatter radar observations at Millstone Hill, USA, from 1976 to 2006, we statistically analyzed the climatological variations of the vertical component of the equivalent winds (VEWs) over Millstone Hill, which are derived from the ionospheric key parameters (the peak electron number density and peak height of the F2 layer, NmF2 and hmF2) on the basis of the servo theory, Liu's method, and measurements from the ion line-of-sight velocity as well. The main results of this analysis are summarized as follows: (1) The values of VEWs over Millstone Hill during nighttime are stronger than in the daytime, and the upward drift dominates most of the day. In 1993, Hagan found that the component of the neutral winds in the magnetic meridion in daytime is weaker than during nighttime under both solar maximum and minimum conditions; he also found that the equatorward winds dominate most of the day. Both results suggest that the thermosphere in Millstone Hill is modulated by the aurorally driven high-latitude circulation cell; that is, during geomagnetic quiet periods, the average auroral activity is strong enough to drive thermospheric circulation equatorward for most of the day at Millstone Hill. Moreover, since ion drag is the strongest during daytime when F region densities are enhanced by photoionization, the wind speeds are smaller during the daytime than in the nighttime. (2) There is equinoctial symmetry in VEWs at Millstone Hill. The amplitudes and phases of VEWs in spring are quite similar to those in autumn. In contrast, the nighttime upward drift in winter is weaker than in summer and the difference becomes more significant with increasing solar activity. This solstice asymmetry indicates that, the aurorally driven circulation in the northern hemisphere at Millstone Hill latitude is weaker in winter due to arctic darkness, because the subsolar point is in the southern hemisphere. (3) The comparison of the VEWs derived from three methods, i.e., the servo theory, Liu's method, and the ISR ion line-of-sight velocity measurements, indicates that the amplitudes and main phase tendencies of these VEWs accord well with each other during nighttime hours. However, the case in the daytime is relatively worse. This daytime discrepancy can be explained in terms of the effects of photochemical processes and the choices of the servo constants. A larger servo constant gives a stronger plasma drift in daytime. Therefore, this study tells how important to choose a suitable constant for deriving VEWs at Millstone Hill.

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Central Xiemisitai is located on the northwest edge of the Junggar Basin, bounded on the north by Sawuer Mountain, and southward Junggar Basin. Geotectonically, it is within the Chengjisi-Ximisitai-Santanghu island arc of Late Paleozoic, between Siberian and Junggar plates. The volcanics in this area mainly consist of acidic volcanic lava, rock assemblage of esite, dacite, and rhyolite, and the transitional phase is comparatively developed. Besides, Si2O of volcanics here covers a large range of 53.91-79.28t %, K2O of 1.71-6.94t%, and Na2O of 2.29-5.45t%, which is a set of metaluminous- peraluminous high K calc-alkaline to calc alkaline mid-acidic volcanic series. In addition, the volcanics are potassic to high-potassic assemblage, with slight shoshonite in. The REE curve of volcanics in central Xiemisitai is rightward and smooth, inclining to LREE enrichment, which reveals the characteristics of island-arc volcanics. Through the lithology changing from neutral to acidic, the negative anomaly of Eu is increasing. The volcanics here deplete HFSE such as Nb, Ti, P, etc., but relatively rich in LILE like Rb, K, Th, etc., possessing geochemistry characteristics of arc volcanics, which means that the lava source region is watery, under the meta-somatic contamination of subducted components. Moreover, high Ba and Sr show volcanics in epicontinental arc environment, and their contemporaneous granitoid rocks are also marked with the characteristics of volcanic arc granite. In central Xiemisitai, the volcanics zircon age of volcanic rhyolite is 422.5Ma± 1.9Ma, mid-late Silurian. Only one sample zircon has been measured for the present, not very convincing, so volcanics here might not come from Devonian volcanism. Consequently, further confirming the volcanic age will play a key role in the research on the beginning of volcanism in Xiemisitai area and even North Xinjiang. This area includes three copper mineralization types: a) from andesite fracture; b) from rhyolite fracture broken zone, with the copper mineralization distributed by veins along the fissure; and c) from quartz veins. The mineralization of earth surface in S24 ore spot is intensive, and the primary geochemistry reconnaissance anomaly is fairly good. According to display data, the maximum content of Cu is as high as 0.9% and as low as 0.05%. Also, ore-control fracture structure is having a considerable scale in the strike of fracture both horizontally and vertically downwards, and the result of the geophysics stratagem EH-4 system reveals obvious low-resistivity anomaly. As a result, we believe that the S24 plot is expected to be a volcanic copper deposit target area.

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Synthetic Geology Information System (SGIS) is an important constituent part of the theory of Engineering Geomechanics Mate-Synthetic (EGMS), and is the information system more suited for the collection, storage, management, analysis and processing to the information coming from engineering geology,' geological engineering and geotechnical engineering. Its contents involve various works and methods of the investigation, design, and construction in different stages of the geological engineering. Engineering geological and three-dimensional modeling and visualization is the fundamental part of the SGIS, and is a theory, method and technique by which, adopting the computer graphics and image processing techniques, the data derived from engineering geological survey and the calculated results obtained from the geomechanical numerical simulation and analysis are converted to the graphics and images displayed on the computer screen and can be processed interactively. In this paper, the significance and realizing approaches of the three-dimensional modeling and visualization for the complex geological mass in the engineering geology are discussed and the methods of taking advantage of the interpolation and fitting for the scattered and field-surveyed data to simulate the geological layers, such as the topography and earth surface, the groundwater table and the stratum boundary, are researched into. At the mean time, in mind the characteristics of the structure of the basic data for three-dimensional modeling, its visual management can be resolved into the engineering surveyed database management module, plot parameter management module and data output module and the requirement for basic data management can be fulfilled. In the paper, the establishment and development of the three-dimensional geological information system are probed tentatively, and an instance of three-dimensional visual Engineering Distribution Information System (EDIS), theConstruction Management Information System for an airport, in which the functions, such as the real-time browse among the three-dimensional virtual-reality landscapes of the airport construction from start to finish, the information query to the airport facility and the building in the housing district and the recording and playback of the animation sets for the browse and the takeoff and landing of the planes, is developed by applying the component-mode three-dimensional virtual-reality geological information system (GIS) software development kits (SDK), so the three-dimensional visual management platform is provided for the airport construction. Moreover, in the gaper, integrated with the three-dimensional topography visualization and its application in the Sichuan-Tibet Highways, the method of the digital elevation model (DEM) data collection from the topographic maps is described, and the three-dimensional visualization and the roaming about the terrain along the highway are achieved through computer language programming. Understanding to the important role played by the varied and unique topographical condition in the gestation and germination of the highly-dense, frequently-arising and severely-endangered geological hazards can be deepened.

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With the development of the technology of earthquake observation, more and more researchers work at many fields' of seismicity using seismic kinetic property, as the result, the study of attenuation has also made great progress, especially in the mechanism of the attenuation and the physical process. Aki put forward single back scattering theory to explain the forming of the seismic coda wave in 1969. Then, researchers started to develop the study in seismic scattering and attenuation. My thesis is also based on that theory. We assume that the Lg wave is a superposition fo high-mode surface waves, the coda of Lg is caused by scattering. Sato proposed Single Isotropic Scattering model (SIS model) to interpreted the scatter property, and he also formulated the geometrical spreading term. Then Xie (1988) developed the single spectral-ratio (SSR) method to obtain the Lg coda Q and the frequency dependent factor n. Later, he get to lateral images in the area of scatter ellipse. SSR method is explored and used in the study of Lg coda waves of regional earthquakes in my thesis. Choosing the earthquakes records with high ratio of signal-noise ,which were recorded at the stations from 1989 to 1999, we obtain the single trace Lg coda Q and its frequency dependent factor n. The results proved that SIS model is the reasonable model to explain the Lg coda wave, and SSR method also can be used to process Lg coda of regional earthquakes to get to the satisfied Lg coda Q. Based on the Lg coda Q we obtained using the former method, we explore the programs to inverse the regional Lg coda Q independently, and then make use of them to inverse the Lg coda Q of Beijing and adjacent area. The inversion result is satisfied. We conclude that the distribution of Qo (Q in lHz) is marked by the inhomogeneity, which is related to the tectonic structure: The value of Qo in uplift area, for example, Yanshan uplift, Taihang uplift, Luxi Uplift, is higher than the depression area, for example, Jizhong depression, Huanghua depression, and Jiyang depression, and the border between the higher Q area and lower Q area is very clear; Lg coda Q is also related to the velocity structure, higher velocity area is also with higher Q, lower velocity area is with lower Q; and higher heat-flow area is companied with lower Q. All in all, the value of Q reflects the difference of characteristics of lithofaces, porosity, the liquid content between the pores and heat flow. So, the Q value difference between uplift area and depression area reveals the difference of tectonic structure, lithology and physical character of the rock. So, the study of Lg coda Q is help to understand the earthquakes propagation mechanism through the inhomogenous medium, the cause of the coda, attenuation mechanism of the coda. Making use of the lateral images of Q, with velocity images, heat flow results, and other experimental result, we will be promoted to understand the complex structure of the crust, its inhomogenous character, and so on.

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Modeling of the gel-immobilized cell system requires accurate measurement of diffusion coefficients. Three methods of the quasi-steady-state (QSS) method, the time-lag (TL) method and a variant quasi-steady-state (VQSS) method were critically assessed and compared for the evaluation of diffusivities using the diffusion cell technique. Experimental data from our laboratory were used for the analysis of the influence of crucial theoretical assumptions not being fulfilled in each method. The results highlighted a risk in obtaining highly variable diffusion coefficients by not validating the QSS and the accuracy of the measurements. In the TL method, the estimation of diffusivities based on the plot intercept that was mostly used in the literature, results in a many fold lower value when compared to that based on the plot slope. The comparison with the QSS and VQSS methods confirmed similar diffusivity obtained by the TL method based on the plot slope. It thus suggested that the correct estimation of diffusivities by the TL method could be based on the plot slope only. Furthermore, the errors associated with the solute mass in the gel, the sample withdrawal and the non-negligible concentration changes in the chambers were also discussed. It is concluded that diffusion cell technique has to be employed cautiously for a correct evaluation of diffusivities. (C) 2001 Elsevier Science B.V. All rights reserved.

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The applicability of capillary electrophoresis/frontal analysis (CE/FA) for determining the binding constants of the drugs propranolol (PRO) and verapamil (VER) to human serum albumin (HSA) was investigated. After direct hydrodynamic injection of a drug-HAS mixture solution into a coated capillary (32 cm x 50 mu m i.d.), the basic drug was eluted as a zonal peak with a plateau region under condition of phosphate buffer (pH 7.4; ionic strength 0.17) at 12 kV positive running voltage. The unbound drug concentrations measured from the plateau peak heights had good correlation coefficients, r > 0.999. Employing the Scatchard plot, the Klotz plot and nonlinear regression, the drug protein binding parameters, the binding constant and the number of binding sites on one protein molecule, were obtained. The binding constant obtained was compared to a reported equilibrium dialysis result and they are basically in good agreement.

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Post-transcriptional modifications in RNA give rise to free modified ribonucleosides circulating in the blood stream and excreted in urine. Due to their abnormal levels in conjunction with several tumor diseases, they have been suggested as possible tumor markers. The developed RP-HPLC method has been applied to analyze the urinary nucleosides in 34 urinary samples from 15 kinds of cancer patients. The statistical analyses showed the urinary nucleoside excretion, especially modified nucleoside levels, in cancer patients were significantly higher than those in normal healthy volunteers. Factor analysis was used to classify the patients with cancer and normal healthy humans. It was found that using 15 urinary nucleoside levels or only five modified nucleoside levels as data vectors the factor analysis plot displayed two almost separate clusters representing each group. (C) 1999 Elsevier Science B.V. All rights reserved.

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Brand placement is to present the information of products and brands through certain entertainments and non-commercial areas. Since 1990's, brand placement has become a major way of spreading advertisement and a new growing point of the global advertising market. In china, it is easily seen from spring festival evening gala of CCTV to all kinds of movie and TV shows, and is thus interested by many brand owners, advertisers and communication researchers. Since 2006, the people in the media circles have begin to take full care of the study of the brand placement. In general, there is still certain distance between the theoretical studies and the reality. It's a general problem over the world and is especially true for China as this was just a new idea. As the biggest global economic entity, China is the most potential and powerful market, thus the market of the brand placement will be huge. To push its development, it's then crucial to have theoretical studies on it. Many questions have not been explained yet in this area, mostly essential is to ask what kind of advantage it acquires compared with the traditional advertisement, if there is, how does such advantage show? What kind of factors influents the market effect of the brand placement? All these questions are not answered yet. Also it's well-known that a successful advertisement relies heavily on the understanding of the culture. Thus a specific thing to deal with is to study the effects according to the Chinese culture, which can make constructive suggestion to the whole industry. Our research is to compare the effects between the brand placement with the ordinary media advertisements, discuss its possible influences, and try to make certain suggestions to the future running and development. Our research obtains the following results by using the movie and advertisement in reality: (1) Like ordinary media ad’s, brand placement can improve the brand recognition of the audience significantly. (2) The ordinary ad's make the people easier to remember them than brand placement, while not too much difference in the brand recognition. (3) The brand placement has a significant 'emotional shifting' effect, i.e. the more positive to the movie, the more you love the built-in brand. (4) It is an important factor that how much brand information is involved in the movie; while how much the plot is involved has great impact on the 'emotional shifting' effect. (5) The familiarity is a great factor for the ad's, it's obvious that the popular products get way better effects through brand replacement. (6) An effective way is to choose those positive, interesting and eye-catching movies and TV shows as carriers of the brand and to use it as natural as possible.

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The quantitative structure-retention relationship is one of the most actively studied topics in the field of chromatography. In this paper, retention parameters of components were used to discriminate the xanthones in a methanol extract of Swertia franchetiana. The extract was analysed by HPLC under two different multistage linear gradient conditions and the retention parameters calculated from these retention data. It was found that the retention parameters of xanthones are in a specific region in the plot of log k(w) vs. S and the xanthones in the extract could be distinguished from other components by this feature. Furthermore, xanthone aglycones and xanthone glucosides could also be discriminated by retention parameters. Copyright (C) 2005 John Wiley Sons, Ltd.