Subjects: Biology >> Ecology submitted time 2018-04-28 Cooperative journals: 《广西植物》
Abstract：荷木（Schima superba）是鼎湖山南亚热带常绿阔叶林群落中的优势种，其种群动态变化对于理解南亚热带常绿阔叶林的群落构建机制具有重要意义。本文分析了鼎湖山南亚热带常绿阔叶林20 ha样地中荷木种群在2005~2017年间的动态变化，并从径级和生境两个方面分析了其死亡率的分布特征。结果表明，荷木种群个体数量从2005~2017年呈减少的态势。在径级方面，荷木的死亡率和相对生长率的变化在不同径级区间呈不同变化规律：径级在1~10 cm范围的荷木相对生长率大并迅速下降，死亡率上升且维持在较高水平；径级在10~50 cm范围的荷木随着径级增大，相对生长率减缓，然后下降，而死亡率不断下降；在50 cm以上的径级范围内，荷木相对生长率小、死亡率大。不同生境中，2010年各个生境死亡率相差不大，2015年高海拔生境（高坡、山脊、高谷）死亡率大于低海拔生境（低坡、低谷），2017年则为低海拔生境大于高海拔。荷木的死亡率与土壤中酸碱度呈正相关关系，而与土壤有机质、总氮、总磷、有效钾、有效氮含量呈负相关关系。
Subjects: Biology >> Botany submitted time 2018-04-28 Cooperative journals: 《广西植物》
Abstract：凯里药市最初由当地少数民族同胞自发组织，药市中不仅有大量的苗族传统药用植物，侗族传统药用植物也十分丰富，但是目前对该药市交易的侗族药用植物鲜有报道，其丰富的传统知识至今仍不被外界所知。为掌握该药市侗族药用植物的现状，本研究运用民族植物学和植物分类学等方法于2014至2017年对凯里药市交易的侗族药用植物进行了6次详细调查。结果表明：该药市出售的侗族药用植物种类较多，共65科100属111种,以广义百合科Liliaceae植物（6种，5.4 %）为主，其次为伞形科Umbelliferae、菊科Compositae、天南星科Araceae植物（各5种，各占4.5%），苦苣苔科Gesneriaceae（4种，3.6%）。从植物生活型来看，草本占有绝对优势，共88种，占79.3%；用药部位具有多样化，但全草类药材占总数的一半。本研究对药市中侗族和苗族交易的药用植物进行了比较分析，得出凯里药市交易的侗族药材具有独特的地域性和民族性，尤以治疗风湿关节、跌打损伤等常见疾病为主。此外，还对凯里药市的可持续发展提出了建议。
Subjects: Biology >> Ecology submitted time 2018-04-28 Cooperative journals: 《广西植物》
Abstract：选取桂林岩溶石山檵木群落不同恢复阶段（灌木阶段、乔灌阶段和小乔林阶段）为研究对象，探究檵木群落不同恢复阶段凋落物层酶对凋落物分解速率的影响。结果表明：檵木群落不同恢复阶段凋落物经过1年分解后，3个阶段凋落物剩余率分别为灌木阶段 (59.58%) 、乔灌阶段 (61.79%) 和小乔林阶段 (62.02%) 。檵木群落不同恢复阶段凋落物分解速率随演替的进行而减小。3个不同恢复阶段凋落物层多酚氧化酶、脲酶、蔗糖酶活性均在12月份最低，多酚氧化酶活性均在3月份最高，脲酶和蔗糖酶活性均在6月份最高。3个恢复阶段纤维素酶活性变化规律趋势一致，均在6月份酶活性最高，灌木阶段纤维素酶活性在3月份最低，乔灌阶段和乔林阶段纤维素酶活性均在9月份最低。檵木群落3个不同恢复阶段的凋落物层酶活性在不同时期均表现为：蔗糖酶>脲酶>纤维素酶>多酚氧化酶。檵木群落不同恢复阶段凋落物层酶活性对凋落物分解速率影响不同。相关性分析表明，檵木群落灌木阶段凋落物层蔗糖酶活性与分解速率呈显著正相关（P < 0.05），乔灌阶段脲酶活性与分解速率呈显著正相关（P < 0.05），小乔林阶段各酶活性与分解速率相关不显著。通径分析表明，蔗糖酶、脲酶和多酚氧化酶是影响灌木阶段凋落物分解速率的重要因素。脲酶、纤维素酶和多酚氧化酶是影响乔灌和小乔林阶段分解速率的重要因素。
Subjects: Astronomy >> Galaxy and Cosmology submitted time 2018-04-25
Abstract： The present paper is a continuation and extension of [1] to CLASH clusters. We study the total, the dark matter density profiles, and correlations in a subgroup of CLASH clusters, as we did for the Newman’s clusters. As in the case of Newman clusters, we find that the DM density profile is strongly influenced by interactions with baryons, and the energy and angular momentum transferred from baryons to DM through dynamical friction. The inner slope of the dark matter density profiles of the clusters are usually flatter than the Navarro-Frenk-White profile inner slope, with maximum value -0.79, and minimum -0.30. As in the case of Newman clusters, there are a series of correlations among the slope α of the dark matter profile, and: a. the core radius of clusters; b. the effective radius R e ; c. the mass of the Brightest Central Galaxy (BCG); d. the total baryonic mass, and stellar mass of the clusters. We also found a correlation between the effective radius and the virial mass. The clusters structure, their total and DM density profiles, and the correlations are understood in a double phase scenario. In the first dissipative phase, the BGC forms. In the second dissipationless phase, the interactions between of baryon cluamps with DM through dynamical friction (DF), flattens the DM distribution. The final result of the two phases is the formation of clusters with different DM distribution, inner slopes, and several correlations between characteristic quantities of the clusters
Peer Review Status:
Awaiting Review
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2018-04-24 Cooperative journals: 《干旱区科学》
Abstract：In most arid and semi-arid regions of the world, domestic livestock and native wildlife share pastures, and their competition for forage and habitat is thought to be a serious conservation issue. Moreover, unmanaged grazing by livestock can cause the population decline in wild ungulates. The diet of an animal species is a determining aspect of its ecological niche, and investigating its diet has been one of the initial steps in basic ecology study of a new species. To get an approximate understanding of the interspecific food relationships of argali (Ovis ammon darwini) between sexes, and sympatric domestic sheep and goats, we compared the diet compositions and diet-overlaps among these herbivores, i.e., male argali, female argali, domestic sheep, and domestic goats in the Mengluoke Mountains of Xinjiang, China by using micro-histological fecal analysis. Female argali, male argali, domestic sheep and domestic goat primarily consumed forbs (43.31%±4.86%), grass (36.02%±9.32%), forbs (41.01%±9.18%), and forbs (36.22%±10.61%), respectively in warm season. All these animals consumed mostly shrubs (female argali: 36.47%±7.56%; male argali: 47.28%±10.75%; domestic sheep: 40.46%±9.56%; and domestic goats: 42.88%±9.34%, respectively) in cold season. The diet-overlaps were relatively high among all species in cold season with values ranging from 0.88 to 0.94. Furthermore, Schoener’s index measured between each possible pair of 4 herbivores increased from the warm season to the cold season. The results illustrate that the high degree of diet-overlap of argali and domestic livestock (sheep and goat) may pose a threat to the survival of the argali in cold season. From the viewpoint of rangeland management and conservation of the endangered argali, the numbers of domestic sheep and goats should be limited in cold season to reduce food competition.
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2018-04-24 Cooperative journals: 《干旱区科学》
RAJAEI, Fatemeh
SARI, Abbas E
SALMANMAHINY, Abdolrassoul
RANDHIR, Timothy O
DELAVAR, Majid
BEHROOZ, Reza D
BAVANI, Alireza M
Abstract：Conversion of forest land to farmland in the Hyrcanian forest of northern Iran increases the nutrient input, especially the phosphorus (P) nutrient, thus impacting the water quality. Modeling the effect of forest loss on surface water quality provides valuable information for forest management. This study predicts the future impacts of forest loss between 2010 and 2040 on P loading in the Tajan River watershed at the sub-watershed level. To understand drivers of the land cover, we used Land Change Modeler (LCM) combining with the Soil Water Assessment Tool (SWAT) model to simulate the impacts of land use change on P loading. We characterized priority management areas for locating comprehensive and cost-effective management practices at the sub-watershed level. Results show that agricultural expansion has led to an intense deforestation. During the future period 2010–2040, forest area is expected to decrease by 34,739 hm2. And the areas of pasture and agriculture are expected to increase by 7668 and 27,071 hm2, respectively. In most sub-watersheds, P pollution will be intensified with the increase in deforestation by the year 2040. And the P concentration is expected to increase from 0.08 to 2.30 mg/L in all of sub-watersheds by the year 2040. It should be noted that the phosphorous concentration exceeds the American Public Health Association′s water quality standard of 0.2 mg/L for P in drinking water in both current and future scenarios in the Tajan River watershed. Only 30% of sub-watersheds will comply with the water quality standards by the year 2040. The finding of the present study highlights the importance of conserving forest area to maintain a stable water quality.
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2018-04-24 Cooperative journals: 《干旱区科学》
BOZOROV, Tohir A
USMANOV, Rustam M
YANG, Honglan
HAMDULLAEV, Shukhrat A
MUSAYEV, Sardorbek
SHAVKIEV, Jaloliddin
NABIEV, Saidgani
ZHANG, Daoyuan
ABDULLAEV, Alisher A
Abstract：Drought is a common abiotic stress that considerably limits crop production. The objective of this study is to explore the influence of water deficiency on the yield, physiologic and metabolomic attributes in upland cotton cultivars (Gossypium hirsutum L). Cotton cultivars, 'Ishonch' and 'Tashkent-6' were selected to study the relationships among their physiologic, metabolomic and yield attributes during water deficiency. Deficit irrigation was designed by modifying the traditional watering protocol to reduce water use. Results indicate that cotton cultivars respond differently to water deficit stress. Water deficit significantly influenced plant height, the number of internodes, and sympodial branches in both cultivars. However, yield components such as the number of bolls, boll seed, lint mass, and individual plant yield were significantly reduced only in 'Tashkent-6'. The leaf area decreased and the specific leaf weight increased in 'Ishonch' under deficit irrigation conditions. However, 'Tashkent-6' demonstrated significant water loss compared to 'Ishonch', and both cultivars showed reduced transpiration rates. Untargeted metabolite profiles of leaves showed clear separation in 'Ishonch', but not in 'Tashkent-6' under deficit irrigation compared to full irrigation. The individual metabolites such as proline and galactinol showed strong association with yield under water deficit stress. Moreover, this study indicates that leaf area and transpiration intensity influence yield during water deficiency. In summary, the correlation among morpho-physiologic, metabolic, and yield components significantly varied between the two cultivars under water deficiency. The flowering stage was sensitive to water stress for both cultivars. The direct relationship between physiology, metabolism, and yield may be a useful selection criterion for determining candidate parents for cotton drought tolerance breeding.
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2018-04-24 Cooperative journals: 《干旱区科学》
LI, Congjuan
LIU, Ran
WANG, Shijie
SUN, Yongqiang
LI, Shengyu
ZHANG, Heng
GAO, Jie
DANG, Yanxi
ZHANG, Lili
Abstract：Extremely saline soils are very harsh environments for the growth and survival of most plant species, however, halophytes can grow well. The underlying mechanism of halophyte to resist high saline is not well understood by us. This study was conducted at the potash mine near the Lop Nur, China, where the effects of the halophyte Suaeda salsa L. on the saline-alkaline soils and its growth and sustainability were investigated. Four plots (in which the salt encrustation layers were removed), with different soil treatments were evaluated: (1) undisturbed soil, with no additional treatment (T1); (2) the slag soil zone, in which a 40-cm layer of slag was placed on the undisturbed soil surface (T2); (3) slag+sandy soil, in which a 20-cm layer of slag was placed in the lower layer and 20 cm of sandy soil, taken from an area about 70 km away from Lop Nur potash mine, where Tamarix species were growing, was placed in the upper layer (T3); and (4) a 40-cm sandy soil layer taken from the area where Tamarix species were growing was placed on undisturbed soil (T4). Soil nutrient contents increased in the four treatments, but salt content only decreased in the T1 treatment. Salt content in the T4 treatment increased over the two-year period, which may be partly attributed to salt deposition from wind-blown dust within the mine and salt accumulation within the surface soil (0–20 cm) in response to high evaporative demands. The S. salsa plants exhibited greater improvements in growth under the T4 treatment than under the T1, T2, and T3 treatments, which demonstrated that low levels of salinity are beneficial for the growth of this species. The T1 treatment was sustainable because of its low cost and superior soil improvement characteristics. Therefore, S. salsa plants not only reduced soil salinity and increased soil nutrient levels, but also ameliorated the plant growth environment, which would be beneficial for both the ecological restoration of the Lop Nur area and similar areas throughout the world.
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2018-04-24 Cooperative journals: 《干旱区科学》
Abstract：Grazing exclusion is one of the most efficient approaches to restore degraded grassland but may negatively affects the recovery of species diversity. Changes in plant species diversity should be a consequence of the ecological assembly process. Local community assembly is influenced by environmental filtering, biotic interactions, and dispersal. However, how these factors potentially contribute to changes to species diversity is poorly understood, especially in harsh environments. In this study, two management sites within a Stipa breviflora desert steppe community (typical natural steppe) were selected in northern China. In one of the two management sites, grazing has been excluded since 2010 and in the other with open grazing by sheep. In August 2016, three plots were established and 100 sampling units were created within each plot in a 5 m×5 m area at the two management sites. To assess the effects of grazing exclusion on S. breviflora steppe, we analyzed the vegetation biomass, species diversity, soil organic carbon, and soil particle size distribution using paired T-tests. In addition, variation partitioning was applied to determine the relative importance of environmental filtering and dispersal limitation. Null mode analysis was used to quantify the influence of biotic interactions in conjunction with EcoSim niche overlap and co-occurrence values. Our results demonstrated that (1) species diversity significantly decreased and the main improvements in soil quality occurred in the topsoil 0–10 cm after the grazing exclusion; (2) environmental filtering was important for community assembly between grazed and fenced grassland and this appears particularly true for soil particle size distribution, which may be well correlated with soil hydrological processes; and (3) however, competitive exclusion may play a significant role within the exclusion. The multiple pathways of assembly may collectively determine negative effects on the restoration of species diversity. Therefore, designers should be aware of the risk of reducing grazing exclusion-induced species diversity and account for manipulating processes. This in turn will reduce dominant species and promote environmental heterogeneity to maximize species diversity in semi-arid regions.
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2018-04-24 Cooperative journals: 《干旱区科学》
Abstract：Precipitation, a natural feature of weather systems in the Earth, is vitally important for the environment of any region. Under global climate change condition, the characteristics of precipitation have changed as a consequence of enhanced global hydrological cycle. The source region of the Yellow River (SRYR), locating within the Qinghai-Tibet Plateau, is sensitive to the global climate change due to its complex orography and fragile ecosystem. To understand the precipitation characteristics and its impacts on the environment in the region, we studied the characteristics of rainy days and precipitation amount of different precipitation classes, such as light (0–5 and 5–10 mm), moderate (10–15, 15–20 and 20–25 mm) and heavy (≥25 mm) rains by analyzing the precipitation data of typical meteorological stations in the SRYR during the period 1961–2014, as well as the trends of persistent rainfall events and drought events. Results showed that annual average precipitation in this area had a non-significant (P>0.05) increasing trend, and 82.5% of the precipitation occurred from May to September. Rainy days of the 0–5 mm precipitation class significantly decreased, whereas the rainy days of 5–10, 10–15, and 20–25 mm precipitation classes increased and that of ≥25 mm precipitation class decreased insignificantly. The persistent rainfall events of 1- or 2-day and more than 2-day showed an increasing trend, with the 1- or 2-day events being more frequent. Meanwhile, the number of short drought periods (≤10 days) increased while long drought periods (>10 days) decreased. Since the 0–5 mm precipitation class had a huge impact on the grasslands productivity; the 5–10, 10–15, and 20–25 mm precipitation classes had positive effects on vegetation which rely on the deep soil water through moving nutrients and water into the root zone of these vegetation or through the plant-microbe interactions; the ≥25 mm precipitation class contributed to the floods; and more persistent rainfall events and fewer long drought events inferred positive effects on agriculture. Thus, these results indicate grassland degradation, less risk of floods, and the upgrading impact of climate change on agriculture. This study may provide scientific knowledge for policymakers to sustain the eco-environmental resources in the SYSR.
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2018-04-24 Cooperative journals: 《干旱区科学》
Abstract：The variation in soil organic carbon density (SOCD) has been widely documented at various spatial and temporal scales. However, an accurate method for examining the attribution of explanatory factors for change in SOCD is still lacking. This study aims to attribute and quantify the key climatic factors, anthropogenic activities, and soil properties associated with SOCD change in the native grasslands of Inner Mongolia, China, by comparing data between the 1960s and the 2010s. In 2007 and 2011, we resampled 142 soil profiles which were originally sampled during 1963–1964 in the native grasslands of Inner Mongolia. SOCD was determined in A horizon (eluvial horizon) of the soil. We selected the explanatory factors based on a random forest method, and explored the relationships between SOCD change and each of the explanatory factors using a linear mixed model. Our results indicated that the change in SOCD varied from the east to the west of Inner Mongolia, and SOCD was 18% lower in the 2010s than in the 1960s. The lower SOCD in the 2010s may primarily be attributed to the increasing in mean annual water surface evaporation, which explained approximately 10% and 50% of the total variation and explainable variation in the change in SOCD, respectively. The sand content of the soil is also a significant explanatory factor for the decrease in SOCD, which explained about 4% and 21% of the total variation and explainable variation in the change in SOCD, respectively. Furthermore, the collection of quantitative information on grazing frequency and duration may also help to improve our understanding of the anthropogenic factors that govern the change in SOCD.
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2018-04-24 Cooperative journals: 《干旱区科学》
Abstract：The main purpose of this study was to explore the dynamic changes of greenhouse gas (GHG) from grasslands under different degradation levels during the growing seasons of Inner Mongolia, China. Grassland degradation is associated with the dynamics of GHG fluxes, e.g., CO2, CH4 and N2O fluxes. As one of the global ecological environmental problems, grassland degradation has changed the vegetation productivity as well as the accumulation and decomposition rates of soil organic matter and thus will influence the carbon and nitrogen cycles of ecosystems, which will affect the GHG fluxes between grassland ecosystems and the atmosphere. Therefore, it is necessary to explore how the exchanges of CO2, CH4 and N2O fluxes between soil and atmosphere are influenced by the grassland degradation. We measured the fluxes of CO2, CH4 and N2O in lightly degraded, moderately degraded and severely degraded grasslands in Inner Mongolia of China during the growing seasons from July to September in 2013 and 2014. The typical semi-arid grassland of Inner Mongolia plays a role as the source of atmospheric CO2 and N2O and the sink for CH4. Compared with CO2 fluxes, N2O and CH4 fluxes were relatively low. The exchange of CO2, N2O and CH4 fluxes between the grassland soil and the atmosphere may exclusively depend on the net exchange rate of CO2 in semi-arid grasslands. The greenhouse gases showed a clear seasonal pattern, with the CO2 fluxes of –33.63–386.36 mg/(m•h), CH4 uptake fluxes of 0.113–0.023 mg/(m•h) and N2O fluxes of –1.68–19.90 µg/(m•h). Grassland degradation significantly influenced CH4 uptake but had no significant influence on CO2 and N2O emissions. Soil moisture and temperature were positively correlated with CO2 emissions but had no significant effect on N2O fluxes. Soil moisture may be the primary driving factor for CH4 uptake. The research results can be in help to better understand the impact of grassland degradation on the ecological environment.
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2018-04-24 Cooperative journals: 《干旱区科学》
Abstract：Knowledge about the effects of vegetation types on soil properties and on water dynamics in the soil profile is critical for revegetation strategies in water-scarce regions, especially the choice of vegetation type and human management measures. We focused on the analysis of the effects of vegetation type on soil hydrological properties and soil moisture variation in the 0–400 cm soil layer based on a long-term (2004―2016) experimental data in the northern Loess Plateau region, China. Soil bulk density (BD), saturated soil hydraulic conductivity (Ks), field capacity (FC) and soil organic carbon (SOC) in 2016, as well as the volumetric soil moisture content during 2004–2016, were measured in four vegetation types, i.e., shrubland (korshinsk peashrub), artificial grassland (alfalfa), fallow land and cropland (millet or potato). Compared with cropland, revegetation with peashrub and alfalfa significantly decreased BD and increased Ks, FC, and SOC in the 0–40 cm soil layer, and fallow land significantly increased FC and SOC in the 0–10 cm soil layer. Soil water storage (SWS) significantly declined in shrubland and grassland in the 40–400 cm soil layer, causing severe soil drought in the deep soil layers. The study suggested that converting cropland to grassland (alfalfa) and shrubland (peashrub) improved soil-hydrological properties, but worsened water conditions in the deep soil profile. However, natural restoration did not intensify deep-soil drying. The results imply that natural restoration could be better than revegetation with peashrub and alfalfa in terms of good soil hydrological processes in the semi-arid Loess Plateau region.
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2018-04-24 Cooperative journals: 《干旱区科学》
Abstract：The rapid desertification of grasslands in Inner Mongolia of China poses a significant ecological threaten to northern China. The combined effects of anthropogenic disturbances (e.g., overgrazing) and biophysical processes (e.g., soil erosion) have led to vegetation degradation and the consequent acceleration of regional desertification. Thus, mitigating the accelerated wind erosion, a cause and effect of grassland desertification, is critical for the sustainable management of grasslands. Here, a combination of mobile wind tunnel experiments and wind erosion model was used to explore the effects of different levels of vegetation coverage, soil moisture and wind speed on wind erosion at different positions of a slope inside an enclosed desert steppe in the Xilamuren grassland of Inner Mongolia. The results indicated a significant spatial difference in wind erosion intensities depending on the vegetation coverage, with a strong decreasing trend from the top to the base of the slope. Increasing vegetation coverage resulted in a rapid decrease in wind erosion as explained by a power function correlation. Vegetation coverage was found to be a dominant control on wind erosion by increasing the surface roughness and by lowering the threshold wind velocity for erosion. The critical vegetation coverage required for effectively controlling wind erosion was found to be higher than 60%. Further, the wind erosion rates were negatively correlated with surface soil moisture and the mass flux in aeolian sand transport increased with increasing wind speed. We developed a mathematical model of wind erosion based on the results of an orthogonal array design. The results from the model simulation indicated that the standardized regression coefficients of the main effects of the three factors (vegetation coverage, soil moisture and wind speed) on the mass flux in aeolian sand transport were in the following order: wind speed>vegetation coverage>soil moisture. These three factors had different levels of interactive effects on the mass flux in aeolian sand transport. Our results will improve the understanding of the interactive effects of wind speed, vegetation coverage and soil moisture in controlling wind erosion in desert steppes, and will be helpful for the design of desertification control programs in future.
Subjects: Physics >> Condensed Matter: Electronic Structure, Electrical, Magnetic, and Optical Properties submitted time 2018-04-24
Abstract： Electric field effects in iron- and copper-based superconductors were studied by using the first-principles calculations based on the density functional theory (DFT). The research objects include iron-based superconductors (KFe2Se2, LaFeAsO, NdFeAsO, and BaFe2As2) and copper-based superconductors (YBa2Cu3O7, HgBa2Ca2Cu3O8, Tl2Ba2CaCu2O8, and Bi2Sr2Ca2Cu3O10). To describe the strong correlation effect of 3d-electrons or 4f-electrons, the GGA+U method was used. Some results were further verified by the HSE method. The densities of states (DOS) were given. The change of the charge densities under electric fields is presented to demonstrate the electric field effect. It is found that the electron clouds of Fe ions in iron-based superconductors, Nd ions in Nd2Fe2As2O2, and Cu ions in copper-based superconductors change obviously. The pattern of the change is more like a rigid-body rotation than an elastic deformation. The author proposed that the rotation of the electron clouds of transition metal ions may be a new medium of superconducting electron pairing. The author’s views about some issues and suggestions on follow-up studies are also presented.
Peer Review Status:Awaiting Review
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-04-24 Cooperative journals: 《计算机应用研究》
Abstract： The appearance and structure of retinal vessels play an important role in the diagnoses in ophthalmic diseases, it also plays an important role in the diagnosis of cardiovascular disease and diabetes, which requires an algorithm to automatically extract the retinal vessels. To enhance the image with imbalanced local illumination caused by retinal diseases in the process of fundus image acquisition, this paper proposed a new unsupervised retinal vessel segmentation method with morphological and Otsu. First, used the combine of the top-hat transformation and the bottom-hat transformation to enhance the contrast between the blood vessels and its background in a retinal image. Next, presented a novel revised method to remove the problem, which is caused by the imbalanced local illumination in the enhanced retinal image. Finally, applied the threshold calculated by Otsu method to extract the retinal vessels. We evaluated the algorithm with two publicly retinal image databases DRIVE and STARE. The experiment results indicate that the segmentation accuracy in DRIVE database achieves 0.9382, the segmentation accuracy in the STARE database achieves 0.9460. The run time of our new method is 1.6 seconds. The new algorithm can accurately extract the retinal vessels. Compared with the traditional retinal vessel segmentation algorithm, its segmentation accuracy and anti-perturbation ability improve.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-04-24 Cooperative journals: 《计算机应用研究》
Abstract： In view of the defects of single feature and the problem of easy to miss when the target is fast changing, this paper proposes an adaptive feature fusion correlation filter tracking algorithm based on learning rate adjustment. The algorithm used complementary gradient features and color features to do the feature fusion, and decides the weights of the features in the fusion feature in next frame by calculating the size of the filter response of each feature, so as to highlight the dominant features and make the target and background more discriminative. After extracting the target, we need to update the filter. In order to avoid the situation that filter can not keep up with the change of the target, the learning rate adjustment mechanism is introduced, so that the update speed of the filter can be adjusted online with the appearance of the target. Therefore, compared with the similar feature fusion algorithm, our algorithm is more accurate and efficient, and the robustness of the fast deformation target is stronger. The experiment shows that our algorithm is better than the existing correlation filter algorithms in accuracy and success rate, and has a certain application price.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-04-24 Cooperative journals: 《计算机应用研究》
Abstract： Aiming at the problems and shortcomings of traditional methods in human motion recognition in classification decision, a novel nonlinear classification decision method based on deep neural network (DNN) and genetic algorithm (GA) merge algorithm is proposed. First, the proposed merging algorithm combines the feature extractors over the entire training set and combines them into two different independent networks. Then use DNN to initialize two independent networks and further use GA to merge the two networks. Then the deviation and weight of the network are expressed as a matrix between each layer of the network. Finally, use DNN to train the bias and weight of the network, and each row in the matrix is treated as a chromosome during the merge process. The experiment uses the standard MNIST data set to evaluate the performance of the proposed algorithm. The evaluation results showed that the crossover and mutation operations during the experiment increased the neuron nodes, improved the recognition performance, and weakened the irrelevant and related neuronal nodes. Therefore, the proposed algorithm has a lower error rate and better network performance.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-04-24 Cooperative journals: 《计算机应用研究》
Abstract： Aiming at the problem of large amount of medical image and the harsh requirements of memory and bandwidth, the paper proposes a new medical image compression approach based on double compression protocol. First, it used square network to reduce the size of images. Then, for each pixel of the image, it chose the optimal amplification method and embedded the coresponding image pixels by digital watermarking technique. Finally, it further compressed the watermark image by JPEG-LS lossless compression to get the final compression image, and to storage and transmit. Through the experiment for MR and CT two types of medical image, the result show that, compared with other methods, the proposed method provides significant improvements and have ensured a better preservation of the image quality notably for high compression ratios.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-04-24 Cooperative journals: 《计算机应用研究》
Abstract： Object detection is the basis of intelligent analysis, however, in the scene of illumination, shadow and clutter background, the problems of object misjudgment and unreasonable clustering is often appeared. Aiming at the above problems, propose a HVS-based object detection algorithm, which can optimize the error judgment and segmentation, and then accorded to the tracking characteristic of HVS and the continuity of object movement, combine the detection results of adjacent frames to achieve completely and accurately extraction object area. Finally, the simulation experiment based on the actual acquisition videos show that the proposed algorithm is more accurate and have good effect and in complex background.
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