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The initiative participation of wind power generators in power system frequency regulation is an inevitable demand to ensure power system safe operation with large-scale wind power integration. However, it is principally difficult for conventional wind turbines to participate in power system frequency regulation. For this reason, solution to this problem is becoming a hot topic in the current studies. This paper systematically reviews the relevant research progresses in the control strategies and the capability assessment of using wind power generators in the power system frequency regulation, including the comparing among the emulating inertia control, the droop control, the rotor speed control, the pitch angle control and the coordinated control. Also, future research in this area is pointed out in the paper. [ABSTRACT FROM AUTHOR]

10Be/7Be is a stratospheric sensitive tracer. In this paper, measurements of 10Be/7Be and surface O3 from October 2005 to May 2006 at Mt. Waliguan (hereafter WLG, 100.898°E, 39.287°N, 3810 m, a.s.l.), China global atmospheric watch (GAW) observatory, are introduced and used to investigate the stratosphere-troposphere transport (STT) and its impact on surface O3 on the Tibetan Plateau. The results show that the magnitude of STT is weak in winter, followed by strengthening from the end of winter to 10 7 10 7 the middle of spring (from mid February to mid April) with large increases in Be, Be, Be/ Be and surface O3. At the end of spring (from the end of April to mid May in this paper), the STT weakened, and the continuous increase of surface O3 at WLG is produced by tropospheric photochemistry reactions. [ABSTRACT FROM AUTHOR]

Information fusion is a challenging task to extract the required information for high-level applications from various homogeneous or heterogeneous sensors. This paper summarizes some improvements in recent five years in the presented structure of information fusion, including estimation fusion, image fusion and others. Some technologies of information fusion and their variants are discussed. Although the state-of-the-art of the algorithms for information fusion have been proposed, there still remains some fundamental challenges with regard to exploiting the emerging multi-sensors' characteristics and their special structures. Finally, some potential prospects of estimation fusion and image fusion are discussed. [ABSTRACT FROM AUTHOR]

The present paper deals with a tectonic event of Late Ordovician age affecting three blocks of China, i.e. South China, North China and Tarim. In the North China and the Tarim platforms, as well as their marginal belts, there was a regional uplift during the early Katian Stage of the Ordovician. The uplift was indicated by the unconformities between the Ordovician successions and overlying late Paleozoic strata. New biostratigraphic studies of conodonts and graptolites from many sections at Longxian and Yaoxian, North China shows that the youngest Ordovician strata are of the early Katian age corresponding to graptolite Diplacanthograptus spiniferus Biozone. The same level has been recognized to represent the uppermost Ordovician in the platform area of Tarim, whereas in the marginal belt the top boundary of the Ordovician is slightly younger, corresponding to the graptolite Dicellograptus complanatus Biozone. Thus, the regional uplift in North China and Tarim is shown by the disconformity between the early Katian strata and Late Paleozoic strata, the onset coinciding with that of the Kwangsian Orogeny in South China. The designation Kwangsian Orogeny later fell into disuse and was replaced by the term Caledonian Orogeny. However, in terms of geographic location, tectonic nature, and the timing of activity, the Caledonian Orogeny differs significantly from the orogenic event in South China, and the continued use of this term in South China is inappropriate and misleading. [ABSTRACT FROM AUTHOR]

Typhoon is considered to play a key role in the dynamical exchange processes taking place between the troposphere and stratosphere. In this paper, the impact of typhoon on the ozone distribution in the upper troposphere and middle stratosphere is investigated using ozone profiles measured by Aura’s Ozone Monitoring Instrument and meteorological fields from reanalysis data. During the passage of Typhoon Hai-Tang in 2005 over the western North Pacific, low values of ozone column above 200 hPa and ozone mixing ratio between the upper troposphere and the middle stratosphere (from 200 to 50 hPa) are observed right above the typhoon’s track, a result due to the strong upward propagation of air associated with overshooting convection in typhoon. A comparative analysis of different stages of Hai-Tang suggests that in the region where typhoon has higher intensity the troposphere-to-stratosphere transport is enhanced. These results indicated that the typhoon has a significant impact on the ozone variation in the upper troposphere and the middle stratosphere. [ABSTRACT FROM AUTHOR]

Understanding the seasonal behaviour of a subtropical forest and its inter-annual variation is crucial to understanding and monitoring its ecosystem function in the context of global warming. Based on the Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index dataset, a wavelet transform method was used to investigate the inter-annual variations of vegetation phenology in a subtropical mountain and hill region in Fujian, China, during 2001-2010. The results show a distinct inter-annual variation of vegetation phenology related to climate variability even if most areas presented non-significant trends. The start dates significantly advanced and end dates delayed in 2003 and 2008, due to anomalously warm conditions. There was generally a gradient of increasing start dates, and earlier end dates of vegetation growing season, due to colder temperatures at higher altitudes. However, the altitudinal phenology relationship also depends on its corresponding rainfall conditions. Earlier start dates were observed at higher altitudes during rainfall deficit years such as 2008, which coincides with relatively abundant rainfall at higher altitudes. This paper reveals that vegetation phenology was coupled with altitudinal gradient, with distinct responses at different combinations of alternate temperature and precipitation conditions variability. [ABSTRACT FROM AUTHOR]

The epidemics of cholera are impacted by many climatic and environmental factors such as precipitation, temperature, elevation and so on. The paper analyzed the suitable degree of V. cholerae in China using MaxEnt based on some geographic and climatic factors, and predicted the cholera risk in each district of China according to the suitable degree. The result shows that the areas in coastal southeast, central China and western Sichuan Basin are relatively suitable for V. cholerae and the suitable degree is higher in the Xinjiang Basin than in surrounding areas. The variables of precipitation, temperature and DEM are three main environmental risky factors that affecting the distribution of cholera in China. The variables of relative humidity, the distance to the sea and air pressure also have impacts on cholera, but sunshine duration and drainage density have little impact. The AUC value of MaxEnt based model is above 0.9 which indicates a high accuracy. [ABSTRACT FROM AUTHOR]

Observations of atmospheric carbon dioxide (CO) from satellites offer new data sources to understand global carbon cycling. The correlation structure of satellite-observed CO can be analyzed and modeled by geostatistical methods, and CO values at unsampled locations can be predicted with a correlation model. Conventional geostatistical analysis only investigates the spatial correlation of CO, and does not consider temporal variation in the satellite-observed CO data. In this paper, a spatiotemporal geostatistical method that incorporates temporal variability is implemented and assessed for analyzing the spatiotemporal correlation structure and prediction of monthly CO in China. The spatiotemporal correlation is estimated and modeled by a product-sum variogram model with a global nugget component. The variogram result indicates a significant degree of temporal correlation within satellite-observed CO data sets in China. Prediction of monthly CO using the spatiotemporal variogram model and space-time kriging procedure is implemented. The prediction is compared with a spatial-only geostatistical prediction approach using a cross-validation technique. The spatiotemporal approach gives better results, with higher correlation coefficient ( r), and less mean absolute prediction error and root mean square error. Moreover, the monthly mapping result generated from the spatiotemporal approach has less prediction uncertainty and more detailed spatial variation of CO than those from the spatial-only approach. [ABSTRACT FROM AUTHOR]

Soil water is the key abiotic limiting factor in desert areas and hydrological processes determine the vegetation composition, patterns and processes in desert regions. The hydrological processes can be altered by vegetation succession. In this paper, we review the major advances in ecohydrological research and their potential impact on plant-water relations in revegetated desert communities. The major advances in ecohydrological research over the past 50 years in desert areas were analyzed using a case study that investigated the long-term ecosystem effects of sand-binding vegetation in the Tengger Desert. Key challenges and opportunities for ecohydrology research in the future are also discussed in the context of the major scientific issues affecting sand binding vegetation. [ABSTRACT FROM AUTHOR]

Urban forest has undergone rapid development in China over the last three decades because of the acceleration of urbanization. Urban forest thus plays an increasingly important role in carbon sequestration at a regional and national scale. As one of the most urbanized cities in China, Shanghai showed an increase of forest coverage from 3% in the 1990s to 13% in 2009. Based on CITY-green model and the second soil survey of Shanghai, the forest biomass carbon (FBC) was estimated to be 0.48 Tg in the urban area and, forest soil organic carbon (SOC) (0-100 cm soil depth) is 2.48 Tg in the urban and suburban areas, respectively. These values are relatively within the median and lower level compared with other Chinese megacities, with the FBC of 0.02 Tg in Harbin to 47.29 Tg in Chongqing and the forest SOC of 1.74 Tg in Nanjing to 418.67 Tg in Chongqing. For the different land-use types in Shanghai, the SOC density ranges from 13.8 (tidal field) to 38.6 t ha (agricultural land). On average, the forest SOC density (31.5 t ha) in Shanghai is lower than that in agricultural lands (38.6 t ha) and higher than that in lawns (26.5 t ha) and gardens (21.3 t ha). In Shanghai, the SOC density in newly established urban parks is generally lower than that in older parks. In the northern and southeastern suburban areas (e.g., Baoshan, Yangpu, and Nanhui districts), greenspace SOC density is higher than that in the central commercial areas (Hongkou, Putuo, Changning, and Zhabei districts) and in newly developed district (Pudong District). Uncertainties still exist in the estimation of urban forest carbon in Shanghai, as well as in other Chinese cities. Thus, future research directions are also discussed in this paper. [ABSTRACT FROM AUTHOR]

This paper presents a 457-year reconstruction of precipitation in the southeastern Qinghai-Tibet Plateau using tree-ring records. Tree-ring samples were collected from the Hengduan Mountains in the southeastern part of the Qinghai-Tibet Plateau, China. A nearly 500-year chronology was developed using tree-ring width records. Correlation analysis shows moisture is the main factor limiting tree growth in this region. Ring-widths were significantly positively correlated with the Palmer Drought Severity Index (PDSI) and precipitation in many months. The highest correlation coefficient was found between the annual growth of trees and precipitation from the previous September to the current June (0.738). Based on this relationship, we reconstructed the precipitation history from 1509 to 2006. The reconstruction explains 54.4% ( R=53.5%, N=49, F=56.12) of the actual precipitation variation during the calibration period (1958-2006). During the reliable period of the reconstruction (1549-2006), some low-frequency climate signals are included, indicating this region has been getting wetter in the last 20 years. The reconstruction documents six apparently dry and five pluvial periods and the 17th century dry period lasted longer than any other. When compared with other recent studies, this study and these earlier reconstructions show a similar trend in the variation of drought and pluvial. Further spatial correlation analysis confirms that the reconstructed precipitation adequately represents the rainfall history of the entire Hengduan Mountain area. The Multi-taper method, a type of spectral analysis, reveals that precipitation in this area had significant ( P<0.01) spectral peaks at 3-5 a, 60 a and 79-85 a. [ABSTRACT FROM AUTHOR]

This paper analyzes the large-scale atmospheric circulation characteristics of anomalous cases of January temperatures that occurred in Northeast China during 1960-2008 and precursory oceanic conditions. The January monthly mean surface air temperature (SAT) anomalies and the duration of low temperature are used to define temperature anomaly cases. The anomalous cyclonic circulation over northeast Asia strengthens the northerly flow in cold Januarys, while the anomalous anticyclonic circulation weakens the northerly flow in the warm Januarys. The negative (positive) North Pacific sea surface temperature anomaly (SSTA) and increased (decreased) sea ice concentration in the Barents-Kara seas in the preceding month are probably linked to the cyclonic (anticyclonic) circulation pattern over northeast Asia in the cold (warm) cases. Further analyses indicate that the preceding oceanic conditions play distinct roles in the SAT anomalies over Northeast China on different time scales. Strong relationships exist between North Pacific SSTA and the SAT in Northeast China on the interannual time scale. On the other hand, the sea ice concentration is more closely associated with the interdecadal variations of SAT in Northeast China. [ABSTRACT FROM AUTHOR]

Xinjiang, the most northwest provincial administrative area of China, was the area where the oriental people met the occidental. The populations in Xinjiang exhibit very high genetic diversity. Previous study revealed that the eastern Xinjiang populations of the Bronze Age were mixed by the Eastern and the Western Eurasians. However, few studies have been performed to reveal when the population admixture started and how far to the west it reached. In this paper, we studied 148 craniofacial traits of 18 skulls from the Bronze Age Liushui graveyard in Khotan (Keriya County) in the southwest of Xinjiang. Seventeen craniometrical parameters of the Khotan samples were then compared with those of other ancient samples from around Xinjiang using dendrogram cluster analysis, principal components analysis, and multidimensional scaling. The results indicated that population sample of Liushui graveyard was mixed by the Western and Eastern Eurasians with about 79% contribution from the east. Therefore, we demonstrated that population admixture between east and west Eurasia can be traced back to as early as 1000 BC in southwest Xinjiang. [ABSTRACT FROM AUTHOR]

Heavy metal pollution is one of the most serious environmental problems in China and a large number of people are threatened by heavy metal pollution. Extensive damage to human organs, such as liver, kidney, digestion system, and nervous system can be caused by uptake of excess heavy metals. Heavy metals in the environment can originate from both natural and anthropogenic sources. Although contamination of heavy metals has been known to be a severe environmental problem for decades, it is still getting worse in recent years and there are few feasible approaches to resolve this problem. Due to their high toxicity, prevalent existence and persistence in the environment, lead (Pb), mercury (Hg), cadmium (Cd), chromium (Cr) and arsenic (As) are commonly considered as the priority heavy metals which should be concerned and their emission should be controlled in China. This paper reviewed the pollution of heavy metals in China, focusing on the following four aspects: current status of heavy metal pollution in China, sources of heavy metals in China, toxicity and potential risk, and possible reduction strategies. [ABSTRACT FROM AUTHOR]

The components and evolution of subcontinental lithospheric mantle beneath the North China Craton and the Yangtze Craton is a current topic in the geological study of China and the carbon isotopic composition of diamond is one of the most direct probes into cratonic lithospheric mantle processes. In this paper, in-situ SIMS (Secondary Ion Mass Spectrometry) techniques were used to analyze the carbon isotope compositions at different internal growth zones of diamonds from Shandong and Liaoning in the North China Craton and Hunan in the Yangtze Craton. It was found that the carbon isotopic range of diamonds from the North China Craton are rather distinct from those of the Yangtze Craton; the former has a range of −6.0/‰ to −2.0‰ (relative to VPDB) with an average value of −3.0‰ in their core areas, which is consistent with global peridotitic diamonds; the diamonds from the Yangtze Craton, however, have a carbon isotopic range from −8.6‰ to −3.0‰ with an average value of −7.4‰ in their core areas, being more consistent with global eclogitic diamonds. The variations of carbon isotope ratios between different internal growth zones in individual diamonds were different in the three diamond localities studied. There was a clear correlation between changes in carbon isotopic composition and phases of diamond dissolution and new growth, while no correlation was observed between δC and internal inclusions. The variations suggest that the carbon isotopic compositions of mantle fluids were changing during the process of diamond crystallization, and that the heterogeneity of the carbon isotopic composition in mantle carbon reservoirs was a more important factor than carbon isotope fractionation in controlling the carbon isotopic compositions and their variation in diamonds. In addition, the preliminary results of in-situ nitrogen analyses demonstrated that the variation of carbon isotopic compositions between the core and outer growth zones does not correlate with nitrogen abundances, implying either that diamonds crystallized in an open environment or that the carbon isotopic composition and nitrogen contents in mantle fluids were controlled by other, not yet understood factors. The experimental results provide hints that the isotopic composition of carbon and its original sources were different in metasomatic fluids controlling diamond formation in the mantle beneath the North China Craton and the Yangtze Craton. [ABSTRACT FROM AUTHOR]

To develop national economy and use the water resources and hydropower resources sufficiently, a lot of high arch dams, with the height of more than 200 m, have been and will be built in China. Although arch dams have good mechanical behavior, there is still failure possibility due to the huge water pressure and high stress level in dam, complex topographic and geologic conditions, formidable environment and high intensity earthquake. As one of the three main aspects concerning the safety of high arch dam, the study on global destruction, has been elaborated in the literatures, and research advance in the other two aspects, namely the failure risk and local damage of high arch dams, will be reviewed in this paper. In recent years, the failure risk of high arch dams has been investigated, and the model for identifying dam failure risk factors has been established. It is shown that the foundation deterioration and strong earthquake are the major risk sources for high dam failure. With the fault tree method, the failure mode and failure probability of high arch dams are studied, and the principle for determining failure mode and the method of calculating failure probability are proposed. Meanwhile, the determination principle of acceptable risk standard for high arch dam was proposed, and the acceptable risk rate and the acceptable standard value of various risk losses were given. For the local damage of arch dam, it is pointed out that the local damage belongs to the strength failure at material level. The study on local failure mechanism of arch dam is reviewed, based on the theories that from traditional strength theory to damage mechanics and meso-mechanics theory. Aiming at the cracking, the main pattern of local failure of high concrete dam, the research advances in the analysis methods and cracking criteria for smeared crack model and discrete crack model are summarized, and the research findings of preventive measures for local failure are shown. [ABSTRACT FROM AUTHOR]

High intensity hadron beam has wide-range important applications. In recent years, several projects with intense-beam hadron accelerator are under design, development or construction in China. We are facing a lot of challenges in beam physics and key technology of the accelerators. Beam loss and beam emittance must be minimized for such a high intensity accelerator. Space charge effect and nonlinear dynamics should be taken into account in beam physics and accelerator design. In this paper we will present the recent research progress in China on beam dynamics, new technology development and beam experiments for intense beam hadron accelerators, including linear accelerator, synchrotron and cyclotron. [ABSTRACT FROM AUTHOR]

In the paper we review the recent progress of studies in unstable nuclei, mainly affiliated with the facilities of radioactive ion beams in China, including both experimental and theoretical aspects of researches. Many experiments for reactions, decays and structures have been performed targeting better understandings of properties of unstable nuclei. Special experimental measurements related to nuclear astrophysics have been done to seek insights into the processes of syntheses of elements in the universe. Theoretical calculations have provided many useful predictions on the behaviors of unstable nuclei, with model developments. Studies covered many mass regions from light to superheavy nuclei, giving plenty of information about the structures of unstable nuclei, towards the limits of existence of atomic nuclei. [ABSTRACT FROM AUTHOR]

Cognition and symbolic thinking are viewed as important features of modern human behavior. Engraved objects are seen as a hallmark of cognition and symbolism, and even as evidence for language. Accumulated evidences including engraved bones, ochre, ostrich eggshells and stone artifacts were unearthed from Africa, Europe, Levant even Siberia Paleolithic sites. But the archaeological evidence for this, including beads, ornaments, burials, performed objects and engraved objects, is rarely discovered in the Pleistocene of East Asia. The present paper reports an engraved stone object unearthed in the Early Late Paleolithic levels about 30 ka BP at the Shuidonggou site (SDG) in northwestern China. It was unearthed in the 1980's excavation from Lower culture unit of SDG1 but was identified in 2011 when the first author of this article observed the collection from the 1980's excavations stored in the Institute of Archaeology of Ningxia Hui Autonomous Region for further detailed lithic analysis. This lithic artifact is the first engraved non-organic object of the Paleolithic period found in China. In order to clarify the details of the incisions and to document the human intentional modifications, we used a KEYENCE VHX-600 Digital Microscope to measure and observe all the incisions in 3-dimensional perspective. Comparing the natural cracks and analyzing many details of the incisions, we argue that incisions on this stone artifact are the result of intentional behaviors by ancient humans. Also, we exclude the possible other causes including animal-induced damages, post-depositional phenomenon and unintentional by-products. Combining all these features, we suggest that the incisions were made by an intentional behavior and were probably of a non-utilitarian character. Because the nature of most other engraved objects in China is debate, we cannot get a clear scenario of the emergence and progress of modern human behavior in North China. But we infer the possible existence of a counting or recording system, or other symbolic behaviors, which reflect considerably evolved cognitive capacities or modern human behavior in the Early Late Paleolithic of East Asia. [ABSTRACT FROM AUTHOR]

Taking into account the fact of global economic integration, this paper improves the RICE model and the MRICES model, and establishes a new integrated assessment model MRICES-2012, which takes Ramsey utility as the standard of fairness. Based on the model, schemes which meet the global emission mitigation targets as well as the interests of developing countries are simulated to assess the international fairness of emission reduction. Therefore, a new feasible scheme is proposed, which can not only reach the Copenhagen Consensus but also ensure interests of every country. Specifically speaking, the US and Japan cut emissions 80% and 70% respectively by 2050 relative to the 1990 level; the EU and other developed countries cut 80% by 2050 relative to 1990 level; high human development countries cut 50% by 2050 relative to 1990 level; all above-mentioned countries start emission reduction from 2020 and keep emission on 2050 level by 2100; China begins emission reduction from 2030 and cuts emission 15% by 2050 and 25% by 2100 relative to 2005 level; medium human development countries keep emission on 2020 level by 2100; low human development countries do not take part in reduction on emission intensity and global emission. [ABSTRACT FROM AUTHOR]

The apatite (U-Th)/He thermochronometry has been used to study the tectono-thermal evolution of mountains and sedimentary basins for over ten years. The closure temperature of helium is important for the apatite (U-Th)/He thermochronometry and has been widely studied by thermal simulation experiments. In this paper, the apatite He closure temperature was studied by establishing the evolutionary pattern between apatite He ages and apatite burial depth based on examined apatite He ages of natural samples obtained from drillholes in the Tarim basin, China. The study showed that the apatite He closure temperature of natural samples in the Tarim basin is approximately 88±5°C, higher than the result (∼75°C) obtained from the thermal simulation experiments. The high He closure temperature resulted from high effective uranium concentration, long-term radiation damage accumulation, and sufficient particle radii. This study is a reevaluation of the conventional apatite He closure temperature and has a great significance in studying the uplifting events in the late period of the basin-mountain tectonic evolution, of which the uplifting time and rates can be determined accurately. [ABSTRACT FROM AUTHOR]

PCDD/Fs in the urban air of Dalian, China were monitored with high-volume active sampler from November 2009 to October 2010. The concentration of ClDD/Fs ranged from 3065 to 49538 fg m, with an average of 10249 fg m. The international toxic equivalents (I-TEQ) value of that was 61.8-1182 fg m, with an average of 235 fg m, which was comparable to those in the other urban locations around the world. It was found that the ClDD/Fs appeared to be present mainly in the particle phase during winter, spring and autumn, while during summer which were dominantly in gas phase. The ratio of ClDD/Fs present in particle phase increased with the increasing level of chlorination. The concentrations of PCDFs and PCDDs decreased with the increase of chlorinated level, while the concentrations of 2,3,7,8-PCDDs congeners increased with the increase of chlorination level. The homolog profiles of the concentrations of PCDFs presented were higher than those of the PCDDs, which indicated the PCDD/Fs pollution source of the air in Dalian was characteristic for thermal source pollution. The correlation analysis of meteorological parameters with the concentrations of ClCDD/Fs was conducted using SPSS packages, and it was found that the ambient temperature and atmospheric pressure were important factors influence the concentration of PCDD/Fs in the air. The respiratory risk and intake dioxins of the residents around the sampling sites were studied in the paper. It was found that Junge-Pankow model was much more accurate in predicting the gas-particle partitioning behavior of PCDD/Fs homologues during winter, while the Harner-Bidleman model shows better agreement with the measured data during winter and summer. [ABSTRACT FROM AUTHOR]

China is a large country by area. In situ monitoring of the environment cannot meet the demand of the society. For large areas, remote sensing is the only viable technology for environmental monitoring of the entire area. Although satellite observation capabilities as well as remotely sensed data acquired on board of satellites from both within and outside China are widely available, research is rare that targets the entire territory of China for environmental monitoring. In this paper, the process of environmental change has been categorized into changes in driving forces, environmental change, materials transport and transformation, concentration and abundance change, exposure and infection change of human and ecosystems, and impacts. The potential in monitoring changes in these various aspects is assessed. The progress of environmental change monitoring over the entire territory of China is reviewed. It is suggested that at the methodological level, remote sensing should not only be applied to observation and experiments as well as understanding the change mechanism, but also be coupled with environmental simulation and forecasting so as to support environmental policy making. At the application level, remote sensing should be used beyond its traditional application fields to include species diversity, biological invasion, public health, air and water quality monitoring. Finally, at the technical level, systematic research should be devoted to the improvement of operational and automatic use of remotely sensed data. [ABSTRACT FROM AUTHOR]

Land-use change simulation for large-scale regions (i.e. provincial regions or countries) is very useful for many global studies. Such simulation, however, is affected by computational capability of general computers. This paper proposes a method to implement cellular automata (CA) for land use change simulation based on graphics processing units (GPUs). This method can be applied to large-scale land-use change simulations by combining the latest GPU high-performance computing technology and CA. We carried out the experiments by simulating land-use change processes at a provincial scale. This involves a lot of sophisticated techniques, such as model mapping, and computational procedure of GPU-CA model. This proposed model has been validated by land-use change simulation in Guangdong Province, China. The comparison indicates that the GPU-CA model is faster than traditional CA by 30 times. Such improvement is crucial for land-use change simulations in provincial regions and countries. The outputs of the simulation can be further used to provide information to other global change models. [ABSTRACT FROM AUTHOR]

We discuss traces from the ichnospecies Undichna unisulca recorded from the Triassic that are reported for the first time in this paper. These fossils are also some of the oldest vertebrate ichnites discovered in China to date. The fish swimming traces ( Undichna unisulca) described originate from the Lower Triassic. These traces were found in the Jialingjiang Formation and are located at a gorge ∼7.5 km from Emei, Sichuan Province, China. The ichnospecies Undichna unisulca consists of a regular sinusoidal wave. The wavelengths and amplitudes are quite constant between each specimen ranging between 28-32 mm and 9-12 mm, respectively. The fish swimming traces and distribution within the same bed are preserved as hypichnial ridges at the undersurface. [ABSTRACT FROM AUTHOR]

The last glacial period was vital for the distribution and evolution of early modern humans in Asia. The Shuidonggou Late Paleolithic site, dated at 30-20 ka BP, accumulated cultural remains during the important late stage of MIS 3 period in the last glacial. These remains represent characteristics of typical Late Paleolithic conditions in North China: high degree of standardization and morphological variability of tool types, exploitation of bone materials, systematic use of body decorations, extensive use of earth-pit hearths, distinct functional spatial organization within habitations, and conversion of subsistence patterns. These characteristics illustrate early modern human behaviors during the late MIS3 period, and provide clues and perspectives for the analysis of early modern human origins in China. At the same time, the conversion of subsistence patterns is considered to be a combination of multiple early modern human behaviors, as well as the result of the Broad Spectrum Revolution. In this paper, we argue for the dynamic mechanism of Broad Spectrum Revolution from a human behavioral and ecological perspective. [ABSTRACT FROM AUTHOR]

Increasing efforts to identify alternate expressions of neuropsychiatric disorders that are broader than the DSM or ICD diagnostic criteria needed to diagnose them reflects a growing consensus that multidimensional expressions of neuropsychiatric disorders may advance the search for underlying etiological or modulatory factors. Endophenotypic research can be considered to be one of the most promising strategies to bridge the gap between genomic complexity and the phenotypic heterogeneity observed in neuropsychiatric disorders. However, the majority of endophenotype studies were limited to our western counterparts, very little has been done and initiated by scholars in mainland China. In this paper, we urge the need to establish a potential central consortium for endophenotypes to study neuropsychiatric disorders in mainland China. In particular, we illustrate a potential example of neurological soft signs in following the steps for building the consortium. [ABSTRACT FROM AUTHOR]

Increasing attention is being paid to the oxy-combustion technique of coal-fired power plants because CO produced from fossil fuel combustion can be captured and sequestrated by it. However, there are many questions about the economic properties of the oxy-combustion technique. In this paper, a detailed techno-economic evaluation study was performed on three typical power plants (2 × 300 MW subcritical, 2 × 600 MW supercritical, 2 × 1000 MW ultra supercritical), as conventional air fired and oxycombustion options in China, by utilizing the authoritative data published in 2010 for the design of coal-fired power plants. Techno-economic evaluation models were set up and costs of electricity generation, CO avoidance costs as well as CO capture costs, were calculated. Moreover, the effects of CO tax and CO sale price on the economic characteristics of oxy-combustion power plants were also considered. Finally, a sensitivity analysis for parameters such as coal sample, coal price, air separation unit price, flue gas treatment unit price, CO capture efficiency, as well as the air excess factor was conducted. The results revealed that: (1) because the oxy-combustion technique has advantages in thermal efficiency, desulfurization efficiency and denitration efficiency, oxy-combustion power plants will reach the economic properties of conventional air fired power plants if, (a) the CO emission is taxed and the high purity CO product can be sold, or (b) there are some policy preferences in financing and coal price for oxy-combustion power plants, or (c) the power consumption and cost of air separation units and flue gas treatment units can be reduced; (2) from subcritical plants to supercritical and finally ultra-supercritical plants, the economics are improving, regardless of whether they are conventional air fired power plants or oxy-combustion power plants. [ABSTRACT FROM AUTHOR]

With the rapid development of wireless communication networks, the fourth generation (4G) has emerged to move beyond the limitations of the third generation (3G), with increased bandwidth, enhanced quality of services, and reduced costs of resources. In this paper, we discuss the key technologies of 4G and focus on surveying the ongoing research in 4G communications in China. The 4G technologies under investigation include multicarrier transmission, multiple antenna techniques, carrier aggregation, relays, cognitive radio, distributed antenna systems, network convergence, and network self-optimization. These technologies are the building blocks of 4G and contribute largely to the requirements of International Mobile Telecommunications Advanced (IMT-Advanced). For each technology, its benefits, research topics, and some existing approaches are examined. Finally, we briefly discuss the challenges and future research issues in 4G systems. [ABSTRACT FROM AUTHOR]

Climate and tectonism are both particularly intense in the Yarlung Zangbo (Tsangpo) Great Canyon in the eastern Himalayan syntaxis, which is characterized by the most rapid landscape evolution of anywhere in the world. Thus, the eastern Himalayan syntaxis is one of the best locations to study the interactions between climate and tectonics. This paper investigates the cooling ages of the Doxong La-Baibung profile using apatite fission track (AFT) dating on 11 bedrock samples at elevations ranging from 4210 to 710 m. There are topographic, climatic, metamorphic, and thermochronological gradients in the profile, providing good conditions to study interactions between climate and tectonics. AFT ages ranged from 4.6±0.6 Ma to 1.7±0.3 Ma, and the mean fission track lengths ranged from 11.0 to 12.4 µm. It was found that the cooling rates revealed by AFT ages increased with decreasing elevation. However, the tendency of the cooling rates revealed by the 40Ar-39Ar ages was different from that indicated by the AFT ages. Moreover, for most districts of the eastern Himalayan syntaxis, the compiled AFT age distribution correlates well with the annual average precipitation, indicating the coupling of the cooling and erosion rates of the near-surface rock and precipitation. The geothermal history modeling results indicate an obvious increase in the cooling and erosion rate between 1.0 and 0.5 Ma. This age is consistent with other research findings for this time, when the vapor channel of the Yarlung Zangbo Great Canyon began to take effect. These evidences suggest that climate, especially precipitation, has acting as a key factor influencing the rapid cooling and erosion in the Yarlung Zangbo Great Canyon since 1-0.5 Ma. [ABSTRACT FROM AUTHOR]

Using in situ zircon dating by LA-ICP-MS and MC-ICP-MS, detrital zircon of 3981±9 Ma age was found in metamorphic rocks of the Ningduo Rock Group, Changdu Block of Northern Qiangtang. This is the oldest age record that has been found in the Qiangtang area. This finding also constitutes the third zircon locality in China with an age older than 3.9 Ga. Thus, the discovery provides new information for the study of Hadean crust. In addition, we found 3.51--3.13 Ga, ~2440 Ma, ~1532 Ma, ~982 Ma and ~618 Ma age peaks from 100 test spots. The younger ages of ~982 Ma and ~618 Ma correspond to the formation of the Rodinian super-continent and the Pan-African event, respectively. These findings suggest a close relationship between these zircons and the Gondwanan super-continent. The age of ~618 Ma defines the lower limit on the deposit time of the protolith for the garnet-micaquartz schist in the Ningduo Rock Group. Zircons with an age of ~982 Ma generally display a negative εHf(t) and a two-stage Hf model with concentrated ages around 1933--2553 Ma. This pattern indicates that the source area of the Ningduo Rock Group underwent a significant separation of depleted mantle into the crust during the Paleoproterozoic Era. However, zircons with ages of 2854--3505 Ma also show a negative εHf(t) and a two-stage Hf model with a concentration of ages around 3784--4316 Ma. These results demonstrate that the source area of the Ningduo Rock Group contains a residual amount of ancient (Hadean) crustal materials. This paper provides new information on the relationship between the basement of the Qiangtang area and the Paleoproterozoic basements of the Gangdese and Himalayan regions, which constrains the northern boundary of Gondwana. [ABSTRACT FROM AUTHOR]

Research and design of a C-band (5712 MHz) high-gradient traveling-wave accelerating structure is being carried out at Shanghai Institute of Applied Physics, Chinese Academy of Sciences. The structure consists of 53 regular disk-loaded cells and two waveguide couplers, and its length is about 1 m. This paper presents a design method for the accelerating structure, an experimental model and the preliminary results of an RF cold test of the model structure. [ABSTRACT FROM AUTHOR]

Cambrian echinoderms, especially eocrinoids, have been reported recently from Guizhou and Yunnan provinces of China, such as the Kaili, Balang, and Guanshan faunas. The present paper reports abundant well-preserved eocrinoids from the Cambrian Mantou Formation of Dalian, Liaoning Province. This new discovery provides additional data on the early evolution of Echinodermata. It also gives us a clue as to where to seek the Cambrian soft-bodied fauna on the margin of the North China Platform. [ABSTRACT FROM AUTHOR]