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According to the problem that achieves robust human actions recognition from image sequences in computer vision, using the Iterative Querying Heuristic algorithm as a guide, a improved Multiple Instance Learning (MIL) method is proposed for human action recognition in video image sequences. Experiments show that the new method can quickly recognize human actions and achieve high recognition rates, and on the Weizmann database validate our analysis.

We propose an efficient method for automatic detection of suspicious behavior in video surveillance data. First of all, we cluster a set of sequences labeled as normal or suspicious. Then, we assign new observation sequences to behavior clusters. We label a sequence as suspicious if it maps to an existing model of suspicious behavior or does not map to any existing model according to the corresponding HMMs. We evaluate our proposed method on a real-world video surveillance and find that the method is very effective at detecting suspicious behavior.

Human behavior recognition is an active research field in computer vision and image processing. A novel method is proposed for human behavior recognition in video image sequences. First of all, a video sequence is represented by extracting space-time interest points. Then Human behavior is represented by activities through Motion Decomposition. The activity comprises labeled bags that are composed of unlabeled instances comprising to action. Final labeled activities are used to train a strong classifier which is used to predict the labels of unseen behavior bags. Experimental results show the effectiveness of the proposed method in comparison with other related works in the literature and can also tolerate noise and interference conditions.

In this paper, we propose an effective approach for detecting moving vehicles in nighttime traffic scenes. We use Multiple Instance Learning method to automatically detect vehicle from video sequences by constructing the Multiple Instance Learning model at nighttime. At first, we extract SIFT feature using SIFT feature extraction algorithm, which is used to characterize moving vehicles at nighttime. Then Multiple Instance Learning model is used for the on-road detection of vehicles at nighttime, in order to improve the detection accuracy, the class label information was used for the learning of the Multiple Instance Learning model. Final experiments were performed and evaluate the proposed method at nighttime under urban traffic condition, the experiment results show that the average detection accuracy is over 96.2%, which validates that the proposed vehicle detection approach is feasible and effective for the on-road detection of vehicles at nighttime and identification in various nighttime environments.

Cu/MgO and MgO nested on the surface of Raney Cu were prepared by a wet-mixing method and used as catalyst for glycerol hydrogenolysis. The texture of Raney Cu/MgO was characterized by X-ray diffraction and transmission electron microscopy, Brunauer–Emmett–Teller, and CO2-temperature-programmed desorption techniques. Results indicated that MgO was well dispersed in the pores of Raney Cu. Moreover, Raney Cu with large specific surface area had a larger contact surface for MgO, and a new phase of Cu–MgO was produced. Glycerol hydrogenolysis was selectively catalyzed under the synergistic effect of Cu and MgO in Cu/MgO catalyst. Under the moderate conditions of 180 °C and 1 MPa H2, the conversion of glycerol was 36.2 wt% and the selectivity for 1,2-propanediol was ~85 wt% when chemical equilibrium.

The electric and magnetic fields generated by the Weibel instability, most of which have a tube-like structure, are of importance for many relevant physical processes in the astrophysics and the inertial confinement fusion. Experimentally, proton radiography is a commonly used method to diagnose the Weibel instability, where the proton deflection introduced from the self-generated electric field is usually ignored. This assumption, however, is in conflict with the experimental observations by Quinn, Fox and Huntington, et al. because the magnetic field with a tube-like structure cannot introduce parallel flux striations on the deflection plane in the proton radiography. In this paper, we re-examine the nature of the proton radiography of the Weibel instability numerically. Two symmetric counterstreaming plasma flows are used to generate the electron Weibel instability with the three-dimensional particle-in-cell simulations. The proton radiography of the Weibel instability generated electric and magnetic fields are calculated with the ray tracing method. Three cases are considered andcompared: only the self-generated electric field E is included, only the self-generated magnetic field B is included, both the electric field E and magnetic field B are included. It is shown that when only E is included, the probe proton flux density perturbation on the detection plane, i.e., δn/n0, is much larger than that when only B is included. Also, when both E and B are included, δn/n0 is almost the same as that when only E is included. This suggests that in the proton radiography of the Weibel instability generated electric and magnetic fields, the deflection from the electric field dominates the radiography, whereas the magnetic field has an ignorable influence. Our conclusion is quite different from that obtained on the traditional assumption that the electric field is ignorable in the radiography. This mainly comes from the spatial structure of the Weibel instability generated magnetic field, which is tube-like and points to the azimuthal direction around the current filaments. When the probe protons pass through the field region, the deflection from the azimuthal magnetic field can be compensated for completely by itself along the passing trajectories especially if the deflection distance inside the field region is small. Whereas for the electric field, which is in the radial direction, the deflection to the probe protons will not be totally compensated for and will finally introduce an evident flux density perturbation into the detection plane. This understanding can beconducive to the comprehension of the experimental results about the proton radiography of the Weibel instability.

Micro-structured targets have been widely used in the interaction between ultra-intense laser and target, aiming at improving the electron accelerating efficiency. In this paper, we perform two-dimensional particle-in-cell (PIC) simulations to study the interaction of the ultra-intense laser pulse with the micro-structured foam-attached target (the foam is composed of low density bubbles and high density interfaces between the bubbles). It is found that at the beginning of the laser-plasma interaction, the fast electrons accelerated at the front surface of the foam freely propagate into the target and drive a return current of cold background electrons. These cold background electrons are restricted to propagate along the interfaces between the bubbles in the foam due to the self-generated large sheath field. As a result, small current filaments are generated in the foam, which then leads to the generation of randomly distributed megagauss magnetic field in the foam layer. This quasistatic magnetic field then acts as an energy-selective " magnetic barrier”: the low-energy electrons are reflected back into the laser acceleration region while the high-energy electrons can penetrate through it. If the reflected electrons enter into the laser field with proper phases, they can be further accelerated to higher energy through cooperative actions of the ultra-intense laser pulse and the sheath field generated due to plasma expansion at the target surface. Our simulation results show that many of the laser accelerated low-energy electrons can be reflected back and accelerated several times until they gain enough energy to penetrate through the magnetic barrier. This is termed the " multiple acceleration mechanism”. Due to this mechanism, the electron acceleration efficiency in the foam-coated target with a thickness of several microns is significantly enhanced in comparison with that in the plane target. This enhancement in the electron acceleration efficiency will be beneficial to many important applications such as the fast ignition. Additionally, foam-coated targets with different bubble radii and layer thickness are also studied, and it is found that the yield of the high energy electrons increases with the radius of bubble size more efficiently than with the bubble thickness. In order to understand the physics more clearly, a single particle model is developed to analyze the simulation results.

Key frames play a very important role in video indexing and retrieval. In this paper, we propose a novel method to extract key frames based on information theory. We use improved Bayesian Information Criterion to determining the number of key frames, and then automatically extract key frames to represent video shot based on information bottleneck cluster method. Experimental results and the comparisons with other methods on various types of video sequences show the effectiveness of the proposed method.

In this paper, we introduce a new ear recognition approach including a feature extraction method and the recognition framework. Firstly, we use a supervised kernel neighborhood preserving projection to extract discriminately ear feature, then we use generalized locally nearest neighbor classifier to recognize ear. Experimental results on USTB ear database show the effectiveness of our method.

Despite sustained efforts for its control made over the past 50+ years, the re-emergence of schistosomiasis in China was noted around the turn of the new millennium. Consequently, a new integrated strategy was proposed to stop the contamination of schistosome eggs to the environment, which emphasizes health education, access to clean water and adequate sanitation, mechanization of agriculture and fencing of water buffaloes, along with chemotherapy. Validation of this integrated control strategy in four pilot counties in the provinces of Anhui, Hubei, Hunan and Jiangxi revealed significant reductions in the rate of Schistosoma japonicum infection in humans and intermediate host snails. Importantly, this strategy showed an impact on diseases beyond schistosomiasis, signified by concomitant reductions in the prevalence of soil-transmitted helminth infections. In view of China's new integrated strategy for transmission control of schistosomiasis showing an ancillary benefit on other helminthic diseases, we encourage others to investigate the scope and limits of integrated control of neglected tropical diseases.

Background Schistosomiasis remains an important public health issue in China and worldwide. Oncomelania hupensis is the unique intermediate host of schistosoma japonicum, and its change influences the distribution of S. japonica. The Three Gorges Dam (TGD) has substantially changed the ecology and environment in the Dongting Lake region. This study investigated the impact of water level and elevation on the survival and habitat of the snails. Methods Data were collected for 16 bottomlands around 4 hydrological stations, which included water, density of living snails (form the Anxiang Station for Schistosomiasis Control) and elevation (from Google Earth). Based on the elevation, sixteen bottomlands were divided into 3 groups. ARIMA models were built to predict the density of living snails in different elevation areas. Results Before closure of TGD, 7 out of 9 years had a water level beyond the warning level at least once at Anxiang hydrological station, compared with only 3 out of 10 years after closure of TGD. There were two severe droughts that happened in 2006 and 2011, with much fewer number of flooding per year compared with other study years. Overall, there was a correlation between water level changing and density of living snails variation in all the elevations areas. The density of living snails in all elevations areas was decreasing after the TGD was built. The relationship between number of flooding per year and the density of living snails was more pronounced in the medium and high elevation areas; the density of living snails kept decreasing from 2003 to 2014. In low elevation area however, the density of living snails decreased after 2003 first and turned to increase after 2011. Our ARIMA prediction models indicated that the snails would not disappear in the Dongting Lake region in the next 7 years. In the low elevation area, the density of living snails would increase slightly, and then stabilize after the year 2017. In the medium elevation region, the change of the density of living snails would be more obvious and would increase till the year 2020. In the high elevation area, the density of living snails would remain stable after the year 2015. Conclusion The TGD influenced water levels and reduced the risk of flooding and the density of living snails in the study region. Based on our prediction models, the density of living snails in all elevations tends to be stabilized. Control of S. japonica would continue to be an important task in the study area in the coming decade., Author Summary Oncomelania hupensis, an amphibious animal, is the unique intermediate host of schistosoma japonicum. Three Gorges Dam (TGD) is a tremendous hydrological project, and it influences the survival of animals downstream. It is studied for several reasons. First, schistosomiasis is still a world-wide parasitic disease which needs to be prevented and controlled. Second, TGD causes the change of water level, and it will impact the existence of snails, but how TGD causes the change of snails and even the epidemics of schistosomiasis is not revealed. In this study, the authors explore the association between TGD and snails. The time-series data contains over 10-year water level downstream TGD and 10-year density of living snails downstream TGD in Dongting Lake Region. These can help to find out the relationship between the change of water level and the change of density of living snails. After this exploration, we attempt to predict the density of living snails 7years later using ARIMA model.

The Working Group on Women in Physics of the Chinese Physical Society in Beijing has worked since 2002 to improve the situation of women in physics in China. Because development is not balanced in vast mainland China—remote areas lag behind in education—a new outreach activity, “Speech in Remote Areas and Inspiration to Young Students,” was launched in 2013. This program aims to broaden the horizons of students in remote areas and to inspire their exploration and enterprise.

A series of Raney Cu-based catalysts (Raney Cu modified by such oxides as ZrO2, Al2O3, ZrO2, MgO, SiO2, TiO2, and ZnO) were prepared by wet-mixing method and used in the hydrogenolysis of glycerol. Modified Raney copper as well as Raney Cu presented the catalytic performance for glycerol hydrogenolysis in different degree, and the yields of 1,2-propanediol as the catalytic selective product were in the order of Cu/MgO > Cu/ZnO > Cu/SiO2 > Cu/TiO2 > Cu/ZrO2 > Cu/Al2O3 > Raney Cu. Obviously, Cu/MgO showed excellent activity and selectivity for glycerol hydrogenolysis by liquid-phase reaction among those catalysts and was characterized by means of X-ray diffraction, transmission electron microscopy, Brunauer–Emmett–Teller, hydrogen temperature programmed desorption, CO2 temperature programmed desorption, and thermogravimetry differential scanning calorimetry. The results showed that the MgO was well dispersed within the pores of Raney Cu, resulting in the generation of new phase Cu–MgO after calcination. The catalytic conversion of glycerol hydrogenolysis using the Raney Cu/MgO catalyst reached 75 wt.%, with a selectivity of 85 wt.% for 1,2-propanediol at 180 °C, 1.0 MPa of hydrogen, and 24 h. The study revealed that the Cu–MgO phase was responsible for high selectivity of 1,2-propanediol in glycerol hydrogenolysis. © 2014 Curtin University of Technology and John Wiley & Sons, Ltd.

To evaluate the effects of comprehensive measures with emphasis on schistosomiasis infectious source control at the embankment level.The comprehensive measures with emphasis on schistosomiasis infectious source control were carried out, and the data of human and Oncomelania snail infection rates were collected and analyzed statistically at embankment levels.In Anbao Embankment, except the other comprehensive measures were performed, 2606 buffaloes were removed. The infection rates of residents reduced from 8.04% before the intervention to 0.7% after the intervention, and the infection rates of snails reduced from 0.56% to 0.05%. In Anli Embankment, 535 buffaloes were removed. In the third year after the intervention, the infection rates of residents reduced from 5.87% to 1.09%, and the infection rates of snails reduced from 0.17% to 0.07%. In Anzao Embankment, 62 buffaloes were removed. In the second year after the intervention, the infection rates of residents reduced from 2.67% to 0.39%, and the infection rates of snails reduced from 1.12% to 0.00%. In Anchang Embankment, the buffaloes were not removed. The human infection rates reduced from 1.76% before the intervention to 1.23% after the intervention.The comprehensive measures with emphasis on schistosomiasis infectious source control, especially the buffalo's removal, are effective in the control of schistosome infection rates of residents and snails.

To evaluate the short-term effect of the black film covering combined with niclosamide on Oncomelania hupensis snail control in marshland and lake regions.A ditch with snails in Anxiang County was selected as the experimental sites. The ditch was divided into 3 groups: a film group, a niclosamide group, and a niclosamide and film group. The snails were surveyed before the test and 1, 3, 5, 7 days after the experiment.After the film covering, the highest temperature of the surface of soil was 63.7 degrees C on the first day, and the temperature higher than 40 degrees C lasted 4.34 hours. On the second day, the highest temperature was 52.3 degrees C, and the temperature higher than 40 degrees C lasted 4.96 hours. On the fourth day and fifth day, the temperature was lower than 30 degrees C, while the temperature was lower than 34 degrees C on the sixth day. On the seventh day of the experiment, the snail death rates of the film group, the niclosamide group, and the niclosamide and film group on the soil surface were 16.36%, 58.40% and 53.57%, respectively. On the seventh day, the snail death rates of the film group, and the niclosamide and film group under the soil were 20.00% and 40.00%, respectively, while no snails were found under the soil in the niclosamide group 3 days after the experiment. In mesh bags, the snail death rates of the film group, the niclosamide group, and the niclosamide and film group were 84.00%, 95.33% and 95.33%, respectively.The short-term effect of the black film covering on snail control is not obvious, and the black film covering does no promote the molluscicidal effect of niclosamide.

To understand the effect of comprehensive schistosomiasis control measures with focus on buffalo and sheep removal in Anxiang City, Dongting Lake area.The data of buffalo and sheep removal, routine schistosomiasis control measures such as disease detection and treatment, Oncomelania snail survey and control, as well as health education were collected and analyzed in Anxiang County, Hunan Province from 2004 to 2012.The schistosome infection rates of people, domestic animals and snails decreased from 11.23%, 17.06% and 1.07% in 2004 when the comprehensive measures had not been implemented to 0.58%, 0 and 0 in 2012, respectively. The average density of infected snails decreased from 0.003 4 snails/0.1 m2 to 0.The comprehensive control measures with focus on buffalo and sheep removal are significantly effective, and can control the transmission of schistosomiasis in marshland and lake regions.

To evaluate the effect of an integrated control strategy and to quantify the spatial-temporal variation of infected snails in the bottomland areas after the strategy was implemented.Based on the geographic database of infected snail distribution at the village level during 2004 - 2010 in Anxiang county, Hunan province, spatial autocorrelation analysis and spatial scan statistics were applied to analyze the spatial-temporal characteristics on the distribution of infected snails.The number of embankments with infected snails in Anxiang county decreased from 23 in 2004 to 10 in 2010, while the rate of frame with infected snail in embankments decreased from 4.32‰ in 2004 to 0.12‰ in 2010. The spatial distribution of infected snails was nonrandom, only in 2004 and 2005 with Moran's I = 0.21 (P0.10) and Moran's I = 0.13 (P0.10) respectively. Data from the local spatial auto-correlation analysis showed that the number of villages with H-H types of auto-correlation model had been gradually decreasing. The results of SaTScan statistics appeared the same as from the local spatial auto-correlation analysis, showing that the number of areas with increased risk was decreasing.The comprehensive measures with emphasis on infectious source control seemed effective for schistosomiasis control program. The current distribution characteristics provided us with evidence that the resource assignment could be more reasonably implemented so as to control schistosomiasis in a more effective way.

To study the dynamic changes of the water body of rivers and Oncomelania snail habitats by using multi-temporal China-Brazil Earth Recourses Satellite-02 images taken in Anxiang County so as to establish the correct procedure for selecting images.CBERS-02 images were collected on 20th December 2003, 10th February 2004, 10th April 2004, 19th June 2004, 10th August 2004 and 27th October 2004. Then the water body information from the study areas based on NDWI was extracted and the areas of water body were calculated to determine the images.The dynamic changes of the water body conformed to the rules of "water in summer and land in winter". Because of the rise of water, the water area in July was the biggest and the water area began to decline from August. The water area in April was the smallest. Then the wet season and the dry season should be June and April.The multi-temporal CBERS-02 images could be used to surveillance the dynamic changes of the water area and helpful in choosing the right images of the wet season and dry season.

To explore the spatial distribution and pattern of advanced schistosomiasis in Anxiang County so as to provide the evidence for improving advanced schistosomiasis control.Based on the geographic database of advanced schistosomiasis distribution at the village level in Anxiang County, Hunan Province, the spatial autocorrelation analysis and spatial scan statistics were applied to analyze the spatial characteristics of distribution of advanced schistosomiasis.The global Moran's I of prevalence rate of advanced schistosomiasis was 0.06 (P0.05) and there was no spatial auto-correlation as a whole. The local spatial auto-correlation analysis showed that there were 9 villages with statistically significant LISA value (P0.05), among which existed high-high, low-high and high-low types of auto-correlation model. The results of SaTScan statistics was the same as local spatial auto-correlation analysis and showed the existence of one cluster area.There are local spatial auto-correlation and spatial aggregation of advanced schistosomiasis in Anxiang County. According to the distribution characteristics, we can assign resource more reasonably and control schistosomiasis more effectively.

An expression for ponderomotive force caused by electromagnetic fields is derived from Vlasov-Maxwell equations in a nonstationary, unmagnetized plasma. Comparison between the authors result and earlier ones is given.

The problem of the coherent motion for an exciton on a linear chain with one impurity is investigated. Analytic and explicit results for the probability propagators and the mean-square displacement are presented with the help of the exact solution of the Volterra integral equation. The long time behavior of the exciton under the influence of the impurity is also discussed.

Despite sustained efforts for its control made over the past 50+ years, the re-emergence of schistosomiasis in China was noted around the turn of the new millennium. Consequently, a new integrated strategy was proposed to stop the contamination of schistosome eggs to the environment, which emphasizes health education, access to clean water and adequate sanitation, mechanization of agriculture and fencing of water buffaloes, along with chemotherapy. Validation of this integrated control strategy in four pilot counties in the provinces of Anhui, Hubei, Hunan and Jiangxi revealed significant reductions in the rate of Schistosoma japonicum infection in humans and intermediate host snails. Importantly, this strategy showed an impact on diseases beyond schistosomiasis, signified by concomitant reductions in the prevalence of soil-transmitted helminth infections. In view of China's new integrated strategy for transmission control of schistosomiasis showing an ancillary benefit on other helminthic diseases, we encourage others to investigate the scope and limits of integrated control of neglected tropical diseases.

To make a therapeutic membrane with aqueous extract from coptis root and explore its adjunctive effects for treating chronic periodontitis.Drug membrane from coptis root aqueous extract was developed; 4 teeth in 30 patients with moderate to advanced periodontitis were randomly divided into four groups: coptis root membrane, iodine glycerin, single drug membrane and blank control group. All parameters including plaque index (PI), probing depth (PD), attachment loss (AL) and bleeding on probing (BOP) were measured at baseline, 4 and 7 weeks after treatment. Analysis of variance and chi-square test were carried out for analysis.In all four groups, there were significant differences of PD, AL, BOP between baseline and 4,7 weeks after treatment (P0.05), the treatment effect of coptis root membrane was significantly superior to that of other three groups (P0.05). Moreover, all the parameters improved continuously.Use of coptis root membrane as an adjunctive method after scaling can significantly improve the treatment effect of periodontitis.

Slow‐time‐scale magnetic fields driven by fast‐time‐scale electric fields are discussed from Vlasov–Maxwell equations in unmagnetized plasma. An equation for slow‐time‐scale magnetic fields is obtained for nonstationary plasma.

A convenient method of three-dimensional ray tracing is suggested in the geometrical optical approximation, in which the laser ray propagation is completely based on the concept of optical trajectory tracing rather than depending upon the effective force and propagation time. This tracing has two obvious advantages that the direct application of Snell's law can be avoided when a ray crosses a different density zone and that to any desired accuracy it takes much less computation time than existing tracing. For Gaussian light beam propagation, in a spherically symmetric plasma atmosphere, the results emphasize that the deposition uniformity is strongly dependent not only on the wavelength of the laser but also on the temperature of the plasma.