This paper proposes a method to design multichannel cosine modulated filter bank for image compression using multiobjective optimization technique. The design problem is a combination of stopband residual energy, leas...This paper proposes a method to design multichannel cosine modulated filter bank for image compression using multiobjective optimization technique. The design problem is a combination of stopband residual energy, least square error of the overall transfer function of the filter bank, coding gain with dc leakage free condition as constraint. The proposed algorithm uses Non-dominated Sorting Genetic Algorithm (NSGA) to minimize the mutually contradictory objective function by minimizing filter tap weights of prototype filter. The algorithm solves this problem by searching solutions that achieve the best compromise between the different objectives criteria. The performance of this algorithm is evaluated in terms of coding gain and peak signal to noise ratio (PSNR). Simulation results on different images are included to illustrate the effectiveness of the proposed algorithm for image compression application.展开更多
Intelligent Decision Support System (IISS) for Bank Loans Risk Classification (BLRC), based on the way of integration Artificial Neural Network (ANN) and Expert System (ES), is proposed. According to the feature of BL...Intelligent Decision Support System (IISS) for Bank Loans Risk Classification (BLRC), based on the way of integration Artificial Neural Network (ANN) and Expert System (ES), is proposed. According to the feature of BLRC, the key financial and non-financial factors are analyzed. Meanwhile, ES and Model Base (MB) which contain ANN are designed . The general framework,interaction and integration of the system are given. In addition, how the system realizes BLRC is elucidated in detail.展开更多
Mesenchymal stem cells(MSCs) as a source for regenerative medicine are now the subject of much clinical attention. There are high expectations due to their safety, low tumorigenic risk, and low ethical concerns. MSC t...Mesenchymal stem cells(MSCs) as a source for regenerative medicine are now the subject of much clinical attention. There are high expectations due to their safety, low tumorigenic risk, and low ethical concerns. MSC therapy has been approved for acute graft-versus host diseases since 2015. Tooth-derived MSCs are known to have a great potential in their proliferation and differentiation capacities, even when compared with bone-marrow-derived MSCs. In particular, stem cells from human exfoliated deciduous teeth(SHEDs) are the best candidates for personal cell banking(dental pulp cell bank), because they can be obtained less invasively in the natural process of individual growth. SHEDs are known to differentiate into hepatocytes. There have been several studies showing the effectiveness of SHEDs on the treatment of liver failure in animal models. They may exert their effects either by repopulation of cells in injured liver or by paracrine mechanisms due to their immuneregulatory functions. Moreover, it may be possible to use each individuals' dental pulp cells as a future source of tailor-made differentiated hepatocytes in the context of a bioartificial liver or liver-on-a-chip to screen for drug toxicity.展开更多
According to the index early warning method, a commercial bank loans risk early warning system based on BP neural networks is proposed. The warning signal is mainly involved with the financial situation signal of loan...According to the index early warning method, a commercial bank loans risk early warning system based on BP neural networks is proposed. The warning signal is mainly involved with the financial situation signal of loaning corporation. Except the structure description of the system structure the demonstration of attemptive designing is also elaborated.展开更多
The rise of social media paves way for unprecedented benefits or risks to several organisations depending on how they adapt to its changes. This rise comes with a great challenge of gaining insights from these big dat...The rise of social media paves way for unprecedented benefits or risks to several organisations depending on how they adapt to its changes. This rise comes with a great challenge of gaining insights from these big data for effective and efficient decision making that can improve quality, profitability, productivity, competitiveness and customer satisfaction. Sentiment analysis is the field that is concerned with the classification and analysis of user generated text under defined polarities. Despite the upsurge of research in sentiment analysis in recent years, there is a dearth in literature on sentiment analysis applied to banks social media data and mostly on African datasets. Against this background, this study applied machine learning technique (support vector machine) for sentiment analysis of Nigerian banks twitter data within a 2-year period, from 1st January 2017 to 31st December 2018. After crawling and preprocessing of the data, LibSVM algorithm in WEKA was used to build the sentiment classification model based on the training data. The performance of this model was evaluated on a pre-labelled test dataset generated from the five banks. The results show that the accuracy of the classifier was 71.8367%. The precision for both the positive and negative classes was above 0.7, the recall for the negative class was 0.696 and that of the positive class was 0.741 which shows the prediction did better than chance in addition to other measures. Applying the model in predicting the sentiments of the five Nigerian banks twitter data reveals that the number of positive tweets within this period was slightly greater than the number of negative tweets. The scatter plots for the sentiments series indicated that, majority of the data falls between 0 and 100 sentiments per day, with few outliers above this range.展开更多
A new equation is proposed for the design of armor units on protected river banks under the combined action of ship-induced waves and river flow.Existing observed field and experimental data in the literature have bee...A new equation is proposed for the design of armor units on protected river banks under the combined action of ship-induced waves and river flow.Existing observed field and experimental data in the literature have been examined and a valuable database has been developed.Different conditions,including the river water depth,flow velocity,river bank slope,Froude number,wave height,wave period,and wave obliquity have been considered.Results from an empirical equation (Bhowmik,1978) that only considers the maximum wave height and river bank slope have been compared with the results calculated by the newly developed equation.Calculated results have also been verified against field data.Results show that not only the maximum wave height and river bank slope but also the water depth,flow velocity,wave length,wave obliquity,and wave period are important parameters for predicting the mean diameter of the armor units,highlighting the multivariate behavior of protecting the river bank in the presence of ship-induced waves and river flow velocity.展开更多
Ex situ seed banking is a practical and cost-effective means of preserving wild plant diversity and a crucial complement to the in situ conservation and restoration of species and habitats. As pressures on the natural...Ex situ seed banking is a practical and cost-effective means of preserving wild plant diversity and a crucial complement to the in situ conservation and restoration of species and habitats. As pressures on the natural environment have grown, so has the call for seed banks to provide scientifically-robust,practical solutions to seed-related problems in nature conservation, from single-species recovery and reintroduction to the restoration of complex, dynamic communities at the largest scales. In this paper, we discuss how the Royal Botanic Gardens, Kew and its Millennium Seed Bank have responded to this call in the United Kingdom. We demonstrate that banked seed collections can provide a range of otherwiseunavailable, high quality, known-origin, genetically-diverse biological materials. The data, expertise and specialist facilities that accompany these collections are also valuable, helping overcome constraints to the collection, production and effective use of native seed. Challenges remain-to ensure ex situ collections protect the species and genetic diversity that will enable plants to adapt to a changing environment, and to find new ways for seed banks to mobilise their resources at a landscape scale.展开更多
Based on the systematic summary of current research on oil bank, the definition of oil bank in the process of fire flooding and its quantitative indices were proposed; and a new one-dimensional positive dry-fire flood...Based on the systematic summary of current research on oil bank, the definition of oil bank in the process of fire flooding and its quantitative indices were proposed; and a new one-dimensional positive dry-fire flooding model considering temperature gradient was established based on the steady flow theory of gas and liquid phases. Single factor analysis and orthogonal experiments were adopted to verify the reliability and reveal the formation mechanisms and the controlling factors of the oil bank. Then the optimal conditions for the oil bank to form were discussed. The study results show the formation of the oil bank is controlled by 3 factors:(1) Oil bank would come into being within a certain temperature interval and above a critical value of temperature gradient(absolute value), with temperature too high or too low and temperature gradient absolute value lower than the critical value, the oil bank couldn't form.(2) For fire flooding process in heavy oil reservoirs, the viscosity of oil influences the width of oil bank and the speed at which oil bank forms; the lower the oil viscosity is, the wider the oil bank is and the faster the oil bank forms.(3) Oil saturation could affect the developing temperature and speed of oil bank. The favorable temperature at which oil bank develops gets lower and the accumulating speed of oil gets faster when the oil saturation is higher. By orthogonal experiments with the model, the optimal combinations of reservoir conditions for forming oil bank during fire flooding in heavy oil reservoirs can be worked out.展开更多
Developing the Changjiang(Yangtze) River and building a developed economic zone along the bank area of the Chanajiang River is a great strategic decision of the national macroeconomic development distribution. This de...Developing the Changjiang(Yangtze) River and building a developed economic zone along the bank area of the Chanajiang River is a great strategic decision of the national macroeconomic development distribution. This decision has both given an impetus to fast development of the regional economy and exacerbated the contradiction among economy and resources and environment. In this paper, some major problems ekisting in economic sustainable development, such as scattered industrial structure, duplicated construction of the great projects, enlarging the development gap of the regional economy and deteriorated environment etc., have been studied. The results show that scattered structure and duplicated distribution of some key industries and projects, especially automobile, electronics and petrochemical industry and communication, power installations, is one of the reasons for low industrial economic benefit; the great development gap among upper, middle and lower reaches areas are enlarging since the 1990’ s; soil erosion, nood disaster and environmental pollution are still exacerliating due to unreasonable over-development. Based on the above analysis, this paper brings out some countermeasures and proposals for increasing the ability of regional sustainable development, including transregional reorganization of industrial structure linking by assets and speeding the process of regional economy integration; gradually controlling and reducing the development gap arnong upper, middle and lower reaches areas through regional cooperation on a mutually beneficial basis; as well as strengthening ecological construction and environmental protection and increasing environmental bearing capacity etc.展开更多
In this paper the design problem of perfect-reconstruction cosine-modulated QMF banks has been formulated as a quadratic-constrained least-squares (QCLS) minimization problem in which all constrained matrices of the Q...In this paper the design problem of perfect-reconstruction cosine-modulated QMF banks has been formulated as a quadratic-constrained least-squares (QCLS) minimization problem in which all constrained matrices of the QCLS optimization problem are symmetric and positive definite. A cost function which is a convex function of desired prototype filter coefficients is constructed so that this kind of QCLS optimization problems can be efficiently solved. So a global minimizer of this problem can be easily obtained. Results of two design examples are presented to support the derivations and analyses.展开更多
This paper examines presence of some stylized facts of short-term stock prices in the banking sector of the Nigerian Stock Market (NSM). Non-normality, lack of autocorrelation in the returns at first lag and significa...This paper examines presence of some stylized facts of short-term stock prices in the banking sector of the Nigerian Stock Market (NSM). Non-normality, lack of autocorrelation in the returns at first lag and significant positive autocorrelation in higher magnitude returns, widely studied in other markets, are investigated using daily closing stock prices of the four major Nigerian banks (Access, First, Guaranty Trust and United Bank for Africa (UBA)), from 2001 to 2013;encompassing periods of different financial scenarios. Jarque-Bera (JB), Doonik-Hansen, Kolmogrov-Smirnov and Ljung-Box (Q) test statistics are applied. Our findings reveal that the four banks stocks behave slightly different, but generally possess the stylized facts found in other markets. Observed is that, while the distributions of the returns for two of these banks (First and UBA) are approximately symmetric and leptokurtic;those of Access and Guaranty Trust banks are significantly non-symmetric and leptokurtic, thus non-normally distributed. Also established is that, while autocorrelation functions of daily returns are either negative or zero, those of both absolute returns and the squared returns are mostly positive. The autocorrelations of absolute returns are found to be predominantly positive and more persistent than those of the squared returns;indicating volatility clustering. Consequently, we conclude that the short-term stock prices of these banks behave like those of other markets. Some implications of the results for financial investment and stock market behaviour in the banking sector of NSM are discussed.展开更多
The soil seed bank is a key indicator of natural regeneration and/or forests resilience after disturbances. This study evaluates the soil seed bank characteristics in two Marantaceae forests plots of Ouesso Forest Ind...The soil seed bank is a key indicator of natural regeneration and/or forests resilience after disturbances. This study evaluates the soil seed bank characteristics in two Marantaceae forests plots of Ouesso Forest Industry (IFO) in north of the Republic of Congo. In each plot, 12 samples were taken per soil layers (0 - 5 cm, 5 - 10 cm, 10 - 15 cm and 15 - 20 cm deep). Diversity and abundance seed were estimated after germination of soil samples. The results revealed 101 seedlings belonging to 17 species for plot 1 and 129 seedlings belonging to 15 species for plot 2. The average densities of germinated seeds were respectively 281 seedling/m<sup>2</sup> and 358 seedling/m<sup>2</sup>. There were no significant differences (p > 0.05) between the mean densities of the two plots. Herbaceous species dominated with percentages of 71% and 73%, respectively in plot 1 and plot 2. Both plots showed potential of regeneration from the soil seed bank. However, this potential seems higher in plot 2. Pioneer taxa were more abundant in the soil seed bank of plot 1 (4 woody pioneer species) than in plot 2 (1 woody pioneer species). The highest species richness was obtained in the first two soil layers (0 - 5 cm and 5 - 10 cm depth) while 25% of species were exclusively found in the deepest layer (15 - 20 cm) in plot 2. The study suggests silvicultural interventions based on planting or enrichment techniques for contribute to sustainable management of Marantaceae forests that could prevent the growth and development of seedlings.展开更多
Ground water samples are collected from south West Bank/Palestine and analyzed for different rare elements (Rb, Zr, U, P, Ti, V), rare earth elements (La, Ce, and Nd), and other common trace metals (Li, Na, Mg, Ca, Sr...Ground water samples are collected from south West Bank/Palestine and analyzed for different rare elements (Rb, Zr, U, P, Ti, V), rare earth elements (La, Ce, and Nd), and other common trace metals (Li, Na, Mg, Ca, Sr, Ba, K, Bi) that most of them usually have no maximum acceptable limits as either they are considered not to be toxic to human health or there is no sufficient data about their toxicity to human health. This study was conducted to determine the water quality of ground water which is used for drinking in the study area. Water samples from ten groundwater wells were obtained in three different dates of the year (November 2012, March 2013, and April 2013). Three water samples were obtained from each well for each sampling date;so a total of 90 water samples were collected from the ten wells. The results obtained from this study suggest a possible risk to the population of the study area given the high concentration of some metals that have no maximum allowed concentration, and the fact that for many people in the study area, ground water is a main source of their water supply.展开更多
By using remote sensing image data of Landsat-5 TM (1988, 1995 and 1998) and Landsat-7 ETM (2002), remote sensing image data, land-use map and DEM had been put in the same coordinate system and projection. In ArcView,...By using remote sensing image data of Landsat-5 TM (1988, 1995 and 1998) and Landsat-7 ETM (2002), remote sensing image data, land-use map and DEM had been put in the same coordinate system and projection. In ArcView, all data had been rasterized as grid data of 30 m×30 m. By Fragstats, landscape pattern indexes had been calculated. Based on the average area, patch density, landscape isolation, boundary density, shape index, fractal dimension, aggregation degree, diversity and evenness index, landscape pattern at different periods and its evolution had been analyzed, revealing the differentiation of spatio-temporal change of landscape pattern at both banks of Pearl River Estuary.展开更多
The combination patterns and depositional characteristics of the carbonate banks are investigated based on outcrop sections, thin sections, and carbon isotopes of Ordovician in the western Tarim Basin, China. Four car...The combination patterns and depositional characteristics of the carbonate banks are investigated based on outcrop sections, thin sections, and carbon isotopes of Ordovician in the western Tarim Basin, China. Four carbonate bank combination patterns are deposited in the Ordovician, western Tarim Basin, including: Reef-Bank Complex (RBC), Algae-Reef-Bank Interbed (ARBI), Thick-Layer Cake Aggradation Bank (TLCAB), and Thin-Layer Cake Retrogradation Bank (TLCRB). All combination patterns show clear periods vertically. The RBC is mainly composed of reefs and bioclastic banks, and the dimension of the RBC depends on the scale of the reefs. Bioclastic banks deposits surround the reefs. The range of the ARBI is determined by the scale of algae-reefs, algae peloid dolomite microfacies and algal dolomite microfacies deposit alternating vertically. TLCAB and TLCRB are deposited as layer-cakes stacking in cycles and extending widely with cross bedding developed. The grains of TLCAB and TLCRB are diverse and multi-source. With the impacting of relative sea level change, biological development and geomorphology, the ARBI, TLCAB or TLCRB, RBC are successively developed from the Lower Ordovician Penglaiba Formation to the Middle Ordovician Yijianfang Formation. The depositional environment analysis of Ordovician indicates that the RBC and ARBI can form effective oil and gas reservoirs, and the TLCAB and TLCRB have the potential to form the huge scale oil and gas reservoirs and to be the crucial targets of exploration for the Ordovician carbonate banks in the future.展开更多
Located south of the West Bank, Wadi Al-Samen is considered one of the most important sources of groundwater recharge for the eastern aquifer in Hebron. It is polluted by sewage originating from domestic and industria...Located south of the West Bank, Wadi Al-Samen is considered one of the most important sources of groundwater recharge for the eastern aquifer in Hebron. It is polluted by sewage originating from domestic and industrial consumption in the Hebron area. Water quality assessment is an important criterion for achieving sustainable development. To evaluate water quality, twenty samples were collected from groundwater sources for two seasons and were analyzed for Physical properties (Total dissolved solids (TDS), Electrical conductivity (EC), potential hydrogen (pH), Temperature (T)), Four major cations (Mg<sup>2+</sup>, Ca<sup>2+</sup>, Na<sup>+</sup> and K<sup>+</sup>), and the Major anions (HCO<sup>-</sup>3</sub>, Cl<sup>-</sup>, and SO<sup>2-</sup>4</sub>);geochemical methods such as Piper scheme were used for the sample result analysis. To characterize wastewater components, six samples were collected from the Wadi discharge for two seasons and were analyzed (potential hydrogen (pH), Electrical Conductivity (EC), Total Dissolved Solid (TDS), Total Suspended Solids (TDS), Total Suspended Solids (TSS), Biological Oxygen Demand (BOD<sub>5</sub>), and Chemical Oxygen Demand (COD). The results of nitrate levels showed that 20% of the ground water samples exceeded the standard limit of the World Health Organization (WHO). The quality of drinking water was assessed using the Water Quality Index (WQI), which suggests that 10% of samples are classified from poor to very poor. The abundance of cations from highest to lowest was found to be: Ca;Mg;Na, and for the anions it is HCO<sub>3</sub>;Cl;SO<sub>4</sub>. The dominant hydrochemical facies of 35% of collected aquifer samples reveal that Ca-Mg-Na-Cl-HCO<sub>3</sub> are in the domain. Evaluation of irrigation suitability was performed using parameters of Sodium adsorption ratio (SAR), electric conductivity (EC), and Salinity. The results in both rounds for EC showed that all water sources are suitable for irrigation according to Todd’s classification. SAR was not suitable in three water resources samples. Wilcox analysis for the two seasons revealed that 85% of samples are not appropriate for irrigation uses.展开更多
In the implementation of the rural revitalization strategy,the banking and financial institutions in Jingzhou City,Hubei Province,under the guidance of the Jingzhou Branch of the People's Bank of China,strive to i...In the implementation of the rural revitalization strategy,the banking and financial institutions in Jingzhou City,Hubei Province,under the guidance of the Jingzhou Branch of the People's Bank of China,strive to improve and develop the financial service system adapted to the characteristics of the countryside in the new period.It has innovated financial service products,improved the quality and efficiency of financial services,increased financial support,and achieved remarkable results.On the basis of the investigation,combined with the relevant written materials and statistical data collected,this paper makes an empirical study on the reality of the city's banking and financial institutions serving the revitalization of rural areas.展开更多
The soil seed bank is an important source of restoration and resilience of disturbed ecosystems. This study evaluates the regeneration potential through the soil seed bank of the shrub savannas of Nguela and Mbe in or...The soil seed bank is an important source of restoration and resilience of disturbed ecosystems. This study evaluates the regeneration potential through the soil seed bank of the shrub savannas of Nguela and Mbe in order to predict the eventual dynamics. Three plots of 0.25 ha subdivided into four sub-plots of 0.015 ha have been installed in each savannah. In total, 48 samples of each savannah, i.e. 96 samples of both savannas, have been taken from the soil layers, 0 - 5 cm, 5 - 10 cm, 10 - 15 cm and 15 - 20 cm. Species diversity and abundance of the soil seed bank have been assessed after germination. The results reveal 167 seedlings belonging to 23 species in the Mbe savannah and 144 seedlings belonging to 14 species in the Nguela savannah. The total densities of the germinated seeds were respectively 463.63 seeds/m<sup>2</sup> and 400 seeds/m<sup>2</sup>. Nevertheless, the 20 cm deep layers have illustrated themselves compared to the superficial layers with densities of 16.29 seeds/m<sup>2</sup> and 21.66 seeds/m<sup>2</sup>, respectively, in the savannas of Mbe and Nguela. Herbaceous species largely dominated, with percentages of 91% and 100%, respectively, in the savannas of Mbe and Nguela. Alone, the Trema orientalis (L.) Blume species has been identified as woody species in the Mbe savannah. The greatest specific richness has been obtained in the first five centimeters of soil, with 21.73% and 28.57% of exclusive species, respectively, in the savannas of Mbe and Nguela. The results reveal that restoration through the soil seed bank would be limited to a single woody species found (T. orientalis). Consequently, the study suggests silvicultural interventions based on planting or enrichment techniques for sustainably managed savannas exposed to anthropogenic disturbances.展开更多
The soil seed bank is considered as an important mechanism for the natural regeneration, resilience and conservation of the forests after disturbances. This study evaluates the characteristics of the soil seed bank in...The soil seed bank is considered as an important mechanism for the natural regeneration, resilience and conservation of the forests after disturbances. This study evaluates the characteristics of the soil seed bank in two post-logging plots of Loundoungou-Toukoulaka Forest Management Unit: one plot exploited in 2008 and another exploited in 2021. In each study plot, 40 samples were collected per soil layer (0 - 5 cm, 5 - 10 cm, 10 - 15 cm, 15 - 20 cm and 20 - 25 cm depth). The species diversity and abundance of the soil seed bank were estimated after soil samples were brought to germination. The results demonstrated that 347 seedlings belonging to 37 species in the plot exploited in 2008 and 418 seedlings belonging to 27 species in that exploited in 2021 germinated during 20 weeks of monitoring. The total densities of the seedlings identified were respectively 1446 seedlings/m<sup>2</sup> and 1742 seedlings/m<sup>2</sup>. The plot exploited in 2021 presented a higher proportion of herbaceous species (93.78%) compared to that exploited in 2008 (82.71%). Two pioneer species were recorded in the plot exploited in 2008. These are Macaranga barteri (0.29%) in the 0 - 5 cm layer and Musanga cecropioides (2.31%) up to 20 cm deep. On the other hand, in the plot exploited in 2021, Macaranga spinosa (0.96%) in the 0 - 5 cm layer and M. cecropioides (0.96%) up to 20 cm deep were identified. In the plot exploited in 2008, the 20 - 25 cm layer demonstrated important proportions in woody species (9%), these are in particular Rubiaceae sp.4 and Nauclea diderrichii. While that exploited in 2021, presented 19% of woody species, namely the species of Rubiaceae sp.4, Rubiaceae sp.5 and N. diderrichii, greatly exceeding the proportions obtained in the 15 - 20 cm layer of the two plots. Nonetheless, N. diderrichii was the only commercial species recorded with densities of 108 seedlings/m<sup>2</sup> and 4 seedlings/m<sup>2</sup>, respectively in the plot exploited in 2008 and that exploited in 2021. Commercial tree species are poorly represented in the soil seed bank. Consequently, the study suggests that to improve the natural regeneration of the commercial species, silvicultural interventions based on planting techniques in the exploited plots should be more effective in order to sustainably manage these production forests.展开更多
文摘This paper proposes a method to design multichannel cosine modulated filter bank for image compression using multiobjective optimization technique. The design problem is a combination of stopband residual energy, least square error of the overall transfer function of the filter bank, coding gain with dc leakage free condition as constraint. The proposed algorithm uses Non-dominated Sorting Genetic Algorithm (NSGA) to minimize the mutually contradictory objective function by minimizing filter tap weights of prototype filter. The algorithm solves this problem by searching solutions that achieve the best compromise between the different objectives criteria. The performance of this algorithm is evaluated in terms of coding gain and peak signal to noise ratio (PSNR). Simulation results on different images are included to illustrate the effectiveness of the proposed algorithm for image compression application.
基金the National Natural Science Fund of China(Approved No.79779986)
文摘Intelligent Decision Support System (IISS) for Bank Loans Risk Classification (BLRC), based on the way of integration Artificial Neural Network (ANN) and Expert System (ES), is proposed. According to the feature of BLRC, the key financial and non-financial factors are analyzed. Meanwhile, ES and Model Base (MB) which contain ANN are designed . The general framework,interaction and integration of the system are given. In addition, how the system realizes BLRC is elucidated in detail.
基金Supported by Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science,No.17K08966(to Ohkoshi S)
文摘Mesenchymal stem cells(MSCs) as a source for regenerative medicine are now the subject of much clinical attention. There are high expectations due to their safety, low tumorigenic risk, and low ethical concerns. MSC therapy has been approved for acute graft-versus host diseases since 2015. Tooth-derived MSCs are known to have a great potential in their proliferation and differentiation capacities, even when compared with bone-marrow-derived MSCs. In particular, stem cells from human exfoliated deciduous teeth(SHEDs) are the best candidates for personal cell banking(dental pulp cell bank), because they can be obtained less invasively in the natural process of individual growth. SHEDs are known to differentiate into hepatocytes. There have been several studies showing the effectiveness of SHEDs on the treatment of liver failure in animal models. They may exert their effects either by repopulation of cells in injured liver or by paracrine mechanisms due to their immuneregulatory functions. Moreover, it may be possible to use each individuals' dental pulp cells as a future source of tailor-made differentiated hepatocytes in the context of a bioartificial liver or liver-on-a-chip to screen for drug toxicity.
基金Supported by the National Science Foundation of China(Approved NO.79770086)
文摘According to the index early warning method, a commercial bank loans risk early warning system based on BP neural networks is proposed. The warning signal is mainly involved with the financial situation signal of loaning corporation. Except the structure description of the system structure the demonstration of attemptive designing is also elaborated.
文摘The rise of social media paves way for unprecedented benefits or risks to several organisations depending on how they adapt to its changes. This rise comes with a great challenge of gaining insights from these big data for effective and efficient decision making that can improve quality, profitability, productivity, competitiveness and customer satisfaction. Sentiment analysis is the field that is concerned with the classification and analysis of user generated text under defined polarities. Despite the upsurge of research in sentiment analysis in recent years, there is a dearth in literature on sentiment analysis applied to banks social media data and mostly on African datasets. Against this background, this study applied machine learning technique (support vector machine) for sentiment analysis of Nigerian banks twitter data within a 2-year period, from 1st January 2017 to 31st December 2018. After crawling and preprocessing of the data, LibSVM algorithm in WEKA was used to build the sentiment classification model based on the training data. The performance of this model was evaluated on a pre-labelled test dataset generated from the five banks. The results show that the accuracy of the classifier was 71.8367%. The precision for both the positive and negative classes was above 0.7, the recall for the negative class was 0.696 and that of the positive class was 0.741 which shows the prediction did better than chance in addition to other measures. Applying the model in predicting the sentiments of the five Nigerian banks twitter data reveals that the number of positive tweets within this period was slightly greater than the number of negative tweets. The scatter plots for the sentiments series indicated that, majority of the data falls between 0 and 100 sentiments per day, with few outliers above this range.
文摘A new equation is proposed for the design of armor units on protected river banks under the combined action of ship-induced waves and river flow.Existing observed field and experimental data in the literature have been examined and a valuable database has been developed.Different conditions,including the river water depth,flow velocity,river bank slope,Froude number,wave height,wave period,and wave obliquity have been considered.Results from an empirical equation (Bhowmik,1978) that only considers the maximum wave height and river bank slope have been compared with the results calculated by the newly developed equation.Calculated results have also been verified against field data.Results show that not only the maximum wave height and river bank slope but also the water depth,flow velocity,wave length,wave obliquity,and wave period are important parameters for predicting the mean diameter of the armor units,highlighting the multivariate behavior of protecting the river bank in the presence of ship-induced waves and river flow velocity.
基金carried out in partnership with Dan Danahar and the Dorothy Stringer School, who also provided funding for this workfunded by Natural England+1 种基金funded by the Esmee Fairbairn Foundationfunded by The People's Postcode Lottery
文摘Ex situ seed banking is a practical and cost-effective means of preserving wild plant diversity and a crucial complement to the in situ conservation and restoration of species and habitats. As pressures on the natural environment have grown, so has the call for seed banks to provide scientifically-robust,practical solutions to seed-related problems in nature conservation, from single-species recovery and reintroduction to the restoration of complex, dynamic communities at the largest scales. In this paper, we discuss how the Royal Botanic Gardens, Kew and its Millennium Seed Bank have responded to this call in the United Kingdom. We demonstrate that banked seed collections can provide a range of otherwiseunavailable, high quality, known-origin, genetically-diverse biological materials. The data, expertise and specialist facilities that accompany these collections are also valuable, helping overcome constraints to the collection, production and effective use of native seed. Challenges remain-to ensure ex situ collections protect the species and genetic diversity that will enable plants to adapt to a changing environment, and to find new ways for seed banks to mobilise their resources at a landscape scale.
基金Supported by the China National Science and Technology Major Project(2016ZX05012-004)the PetroChina Science and Technology Project(2016B-1402)
文摘Based on the systematic summary of current research on oil bank, the definition of oil bank in the process of fire flooding and its quantitative indices were proposed; and a new one-dimensional positive dry-fire flooding model considering temperature gradient was established based on the steady flow theory of gas and liquid phases. Single factor analysis and orthogonal experiments were adopted to verify the reliability and reveal the formation mechanisms and the controlling factors of the oil bank. Then the optimal conditions for the oil bank to form were discussed. The study results show the formation of the oil bank is controlled by 3 factors:(1) Oil bank would come into being within a certain temperature interval and above a critical value of temperature gradient(absolute value), with temperature too high or too low and temperature gradient absolute value lower than the critical value, the oil bank couldn't form.(2) For fire flooding process in heavy oil reservoirs, the viscosity of oil influences the width of oil bank and the speed at which oil bank forms; the lower the oil viscosity is, the wider the oil bank is and the faster the oil bank forms.(3) Oil saturation could affect the developing temperature and speed of oil bank. The favorable temperature at which oil bank develops gets lower and the accumulating speed of oil gets faster when the oil saturation is higher. By orthogonal experiments with the model, the optimal combinations of reservoir conditions for forming oil bank during fire flooding in heavy oil reservoirs can be worked out.
文摘Developing the Changjiang(Yangtze) River and building a developed economic zone along the bank area of the Chanajiang River is a great strategic decision of the national macroeconomic development distribution. This decision has both given an impetus to fast development of the regional economy and exacerbated the contradiction among economy and resources and environment. In this paper, some major problems ekisting in economic sustainable development, such as scattered industrial structure, duplicated construction of the great projects, enlarging the development gap of the regional economy and deteriorated environment etc., have been studied. The results show that scattered structure and duplicated distribution of some key industries and projects, especially automobile, electronics and petrochemical industry and communication, power installations, is one of the reasons for low industrial economic benefit; the great development gap among upper, middle and lower reaches areas are enlarging since the 1990’ s; soil erosion, nood disaster and environmental pollution are still exacerliating due to unreasonable over-development. Based on the above analysis, this paper brings out some countermeasures and proposals for increasing the ability of regional sustainable development, including transregional reorganization of industrial structure linking by assets and speeding the process of regional economy integration; gradually controlling and reducing the development gap arnong upper, middle and lower reaches areas through regional cooperation on a mutually beneficial basis; as well as strengthening ecological construction and environmental protection and increasing environmental bearing capacity etc.
基金Climbing Programme-National Key Project for Foundamental Research in China,Grant NSC92097National Natural Science Foundation of China
文摘In this paper the design problem of perfect-reconstruction cosine-modulated QMF banks has been formulated as a quadratic-constrained least-squares (QCLS) minimization problem in which all constrained matrices of the QCLS optimization problem are symmetric and positive definite. A cost function which is a convex function of desired prototype filter coefficients is constructed so that this kind of QCLS optimization problems can be efficiently solved. So a global minimizer of this problem can be easily obtained. Results of two design examples are presented to support the derivations and analyses.
文摘This paper examines presence of some stylized facts of short-term stock prices in the banking sector of the Nigerian Stock Market (NSM). Non-normality, lack of autocorrelation in the returns at first lag and significant positive autocorrelation in higher magnitude returns, widely studied in other markets, are investigated using daily closing stock prices of the four major Nigerian banks (Access, First, Guaranty Trust and United Bank for Africa (UBA)), from 2001 to 2013;encompassing periods of different financial scenarios. Jarque-Bera (JB), Doonik-Hansen, Kolmogrov-Smirnov and Ljung-Box (Q) test statistics are applied. Our findings reveal that the four banks stocks behave slightly different, but generally possess the stylized facts found in other markets. Observed is that, while the distributions of the returns for two of these banks (First and UBA) are approximately symmetric and leptokurtic;those of Access and Guaranty Trust banks are significantly non-symmetric and leptokurtic, thus non-normally distributed. Also established is that, while autocorrelation functions of daily returns are either negative or zero, those of both absolute returns and the squared returns are mostly positive. The autocorrelations of absolute returns are found to be predominantly positive and more persistent than those of the squared returns;indicating volatility clustering. Consequently, we conclude that the short-term stock prices of these banks behave like those of other markets. Some implications of the results for financial investment and stock market behaviour in the banking sector of NSM are discussed.
文摘The soil seed bank is a key indicator of natural regeneration and/or forests resilience after disturbances. This study evaluates the soil seed bank characteristics in two Marantaceae forests plots of Ouesso Forest Industry (IFO) in north of the Republic of Congo. In each plot, 12 samples were taken per soil layers (0 - 5 cm, 5 - 10 cm, 10 - 15 cm and 15 - 20 cm deep). Diversity and abundance seed were estimated after germination of soil samples. The results revealed 101 seedlings belonging to 17 species for plot 1 and 129 seedlings belonging to 15 species for plot 2. The average densities of germinated seeds were respectively 281 seedling/m<sup>2</sup> and 358 seedling/m<sup>2</sup>. There were no significant differences (p > 0.05) between the mean densities of the two plots. Herbaceous species dominated with percentages of 71% and 73%, respectively in plot 1 and plot 2. Both plots showed potential of regeneration from the soil seed bank. However, this potential seems higher in plot 2. Pioneer taxa were more abundant in the soil seed bank of plot 1 (4 woody pioneer species) than in plot 2 (1 woody pioneer species). The highest species richness was obtained in the first two soil layers (0 - 5 cm and 5 - 10 cm depth) while 25% of species were exclusively found in the deepest layer (15 - 20 cm) in plot 2. The study suggests silvicultural interventions based on planting or enrichment techniques for contribute to sustainable management of Marantaceae forests that could prevent the growth and development of seedlings.
文摘Ground water samples are collected from south West Bank/Palestine and analyzed for different rare elements (Rb, Zr, U, P, Ti, V), rare earth elements (La, Ce, and Nd), and other common trace metals (Li, Na, Mg, Ca, Sr, Ba, K, Bi) that most of them usually have no maximum acceptable limits as either they are considered not to be toxic to human health or there is no sufficient data about their toxicity to human health. This study was conducted to determine the water quality of ground water which is used for drinking in the study area. Water samples from ten groundwater wells were obtained in three different dates of the year (November 2012, March 2013, and April 2013). Three water samples were obtained from each well for each sampling date;so a total of 90 water samples were collected from the ten wells. The results obtained from this study suggest a possible risk to the population of the study area given the high concentration of some metals that have no maximum allowed concentration, and the fact that for many people in the study area, ground water is a main source of their water supply.
基金Supported by Natural Science Foundation of China(40534019)~~
文摘By using remote sensing image data of Landsat-5 TM (1988, 1995 and 1998) and Landsat-7 ETM (2002), remote sensing image data, land-use map and DEM had been put in the same coordinate system and projection. In ArcView, all data had been rasterized as grid data of 30 m×30 m. By Fragstats, landscape pattern indexes had been calculated. Based on the average area, patch density, landscape isolation, boundary density, shape index, fractal dimension, aggregation degree, diversity and evenness index, landscape pattern at different periods and its evolution had been analyzed, revealing the differentiation of spatio-temporal change of landscape pattern at both banks of Pearl River Estuary.
基金financially supported by the National Natural Science Foundation of China grant(41102087)the Key Project of the National Science & Technology grant(2011ZX05005-002-010HZ,2011ZX05009-002)+1 种基金National Basic Research Program of China grant (2012CB214802)the Special Foundation for Doctoral Subjects in China University of Geosciences(Beijing) grant(2011PY0199)
文摘The combination patterns and depositional characteristics of the carbonate banks are investigated based on outcrop sections, thin sections, and carbon isotopes of Ordovician in the western Tarim Basin, China. Four carbonate bank combination patterns are deposited in the Ordovician, western Tarim Basin, including: Reef-Bank Complex (RBC), Algae-Reef-Bank Interbed (ARBI), Thick-Layer Cake Aggradation Bank (TLCAB), and Thin-Layer Cake Retrogradation Bank (TLCRB). All combination patterns show clear periods vertically. The RBC is mainly composed of reefs and bioclastic banks, and the dimension of the RBC depends on the scale of the reefs. Bioclastic banks deposits surround the reefs. The range of the ARBI is determined by the scale of algae-reefs, algae peloid dolomite microfacies and algal dolomite microfacies deposit alternating vertically. TLCAB and TLCRB are deposited as layer-cakes stacking in cycles and extending widely with cross bedding developed. The grains of TLCAB and TLCRB are diverse and multi-source. With the impacting of relative sea level change, biological development and geomorphology, the ARBI, TLCAB or TLCRB, RBC are successively developed from the Lower Ordovician Penglaiba Formation to the Middle Ordovician Yijianfang Formation. The depositional environment analysis of Ordovician indicates that the RBC and ARBI can form effective oil and gas reservoirs, and the TLCAB and TLCRB have the potential to form the huge scale oil and gas reservoirs and to be the crucial targets of exploration for the Ordovician carbonate banks in the future.
文摘Located south of the West Bank, Wadi Al-Samen is considered one of the most important sources of groundwater recharge for the eastern aquifer in Hebron. It is polluted by sewage originating from domestic and industrial consumption in the Hebron area. Water quality assessment is an important criterion for achieving sustainable development. To evaluate water quality, twenty samples were collected from groundwater sources for two seasons and were analyzed for Physical properties (Total dissolved solids (TDS), Electrical conductivity (EC), potential hydrogen (pH), Temperature (T)), Four major cations (Mg<sup>2+</sup>, Ca<sup>2+</sup>, Na<sup>+</sup> and K<sup>+</sup>), and the Major anions (HCO<sup>-</sup>3</sub>, Cl<sup>-</sup>, and SO<sup>2-</sup>4</sub>);geochemical methods such as Piper scheme were used for the sample result analysis. To characterize wastewater components, six samples were collected from the Wadi discharge for two seasons and were analyzed (potential hydrogen (pH), Electrical Conductivity (EC), Total Dissolved Solid (TDS), Total Suspended Solids (TDS), Total Suspended Solids (TSS), Biological Oxygen Demand (BOD<sub>5</sub>), and Chemical Oxygen Demand (COD). The results of nitrate levels showed that 20% of the ground water samples exceeded the standard limit of the World Health Organization (WHO). The quality of drinking water was assessed using the Water Quality Index (WQI), which suggests that 10% of samples are classified from poor to very poor. The abundance of cations from highest to lowest was found to be: Ca;Mg;Na, and for the anions it is HCO<sub>3</sub>;Cl;SO<sub>4</sub>. The dominant hydrochemical facies of 35% of collected aquifer samples reveal that Ca-Mg-Na-Cl-HCO<sub>3</sub> are in the domain. Evaluation of irrigation suitability was performed using parameters of Sodium adsorption ratio (SAR), electric conductivity (EC), and Salinity. The results in both rounds for EC showed that all water sources are suitable for irrigation according to Todd’s classification. SAR was not suitable in three water resources samples. Wilcox analysis for the two seasons revealed that 85% of samples are not appropriate for irrigation uses.
文摘In the implementation of the rural revitalization strategy,the banking and financial institutions in Jingzhou City,Hubei Province,under the guidance of the Jingzhou Branch of the People's Bank of China,strive to improve and develop the financial service system adapted to the characteristics of the countryside in the new period.It has innovated financial service products,improved the quality and efficiency of financial services,increased financial support,and achieved remarkable results.On the basis of the investigation,combined with the relevant written materials and statistical data collected,this paper makes an empirical study on the reality of the city's banking and financial institutions serving the revitalization of rural areas.
文摘The soil seed bank is an important source of restoration and resilience of disturbed ecosystems. This study evaluates the regeneration potential through the soil seed bank of the shrub savannas of Nguela and Mbe in order to predict the eventual dynamics. Three plots of 0.25 ha subdivided into four sub-plots of 0.015 ha have been installed in each savannah. In total, 48 samples of each savannah, i.e. 96 samples of both savannas, have been taken from the soil layers, 0 - 5 cm, 5 - 10 cm, 10 - 15 cm and 15 - 20 cm. Species diversity and abundance of the soil seed bank have been assessed after germination. The results reveal 167 seedlings belonging to 23 species in the Mbe savannah and 144 seedlings belonging to 14 species in the Nguela savannah. The total densities of the germinated seeds were respectively 463.63 seeds/m<sup>2</sup> and 400 seeds/m<sup>2</sup>. Nevertheless, the 20 cm deep layers have illustrated themselves compared to the superficial layers with densities of 16.29 seeds/m<sup>2</sup> and 21.66 seeds/m<sup>2</sup>, respectively, in the savannas of Mbe and Nguela. Herbaceous species largely dominated, with percentages of 91% and 100%, respectively, in the savannas of Mbe and Nguela. Alone, the Trema orientalis (L.) Blume species has been identified as woody species in the Mbe savannah. The greatest specific richness has been obtained in the first five centimeters of soil, with 21.73% and 28.57% of exclusive species, respectively, in the savannas of Mbe and Nguela. The results reveal that restoration through the soil seed bank would be limited to a single woody species found (T. orientalis). Consequently, the study suggests silvicultural interventions based on planting or enrichment techniques for sustainably managed savannas exposed to anthropogenic disturbances.
文摘The soil seed bank is considered as an important mechanism for the natural regeneration, resilience and conservation of the forests after disturbances. This study evaluates the characteristics of the soil seed bank in two post-logging plots of Loundoungou-Toukoulaka Forest Management Unit: one plot exploited in 2008 and another exploited in 2021. In each study plot, 40 samples were collected per soil layer (0 - 5 cm, 5 - 10 cm, 10 - 15 cm, 15 - 20 cm and 20 - 25 cm depth). The species diversity and abundance of the soil seed bank were estimated after soil samples were brought to germination. The results demonstrated that 347 seedlings belonging to 37 species in the plot exploited in 2008 and 418 seedlings belonging to 27 species in that exploited in 2021 germinated during 20 weeks of monitoring. The total densities of the seedlings identified were respectively 1446 seedlings/m<sup>2</sup> and 1742 seedlings/m<sup>2</sup>. The plot exploited in 2021 presented a higher proportion of herbaceous species (93.78%) compared to that exploited in 2008 (82.71%). Two pioneer species were recorded in the plot exploited in 2008. These are Macaranga barteri (0.29%) in the 0 - 5 cm layer and Musanga cecropioides (2.31%) up to 20 cm deep. On the other hand, in the plot exploited in 2021, Macaranga spinosa (0.96%) in the 0 - 5 cm layer and M. cecropioides (0.96%) up to 20 cm deep were identified. In the plot exploited in 2008, the 20 - 25 cm layer demonstrated important proportions in woody species (9%), these are in particular Rubiaceae sp.4 and Nauclea diderrichii. While that exploited in 2021, presented 19% of woody species, namely the species of Rubiaceae sp.4, Rubiaceae sp.5 and N. diderrichii, greatly exceeding the proportions obtained in the 15 - 20 cm layer of the two plots. Nonetheless, N. diderrichii was the only commercial species recorded with densities of 108 seedlings/m<sup>2</sup> and 4 seedlings/m<sup>2</sup>, respectively in the plot exploited in 2008 and that exploited in 2021. Commercial tree species are poorly represented in the soil seed bank. Consequently, the study suggests that to improve the natural regeneration of the commercial species, silvicultural interventions based on planting techniques in the exploited plots should be more effective in order to sustainably manage these production forests.