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The development of objective image quality assessment metrics aligned with human perception is of fundamental importance to numerous image processing applications. In this paper, an objective image quality assessment approach based on saliency map is proposed. By local shift estimation method, the retargeted image is resized to the same size as the reference image. A gradient magnitude similarity map is computed by comparing the retargeted and reference images. The more similarly, the brighter of pixels in the gradient magnitude similarity map. At the same time, a saliency map of reference image is achieved by visual attention. Finally, an overall image quality score is computed from the gradient magnitude similarity map via saliency pooling strategy. The most important step in our approach is to generate a gradient magnitude similarity map that indicates at each spatial location in the source image how the structural information is preserved in the retargeted image. There are two key contributions in this paper, one is that we add the texture feature in computing saliency map because image gradient is very sensitive to texture information, and the other is that we propose a new objective image quality metrics by introducing saliency map into image quality evaluation. Experimental results indicate that the evaluation indexes of our approach are better than existing methods in the literature.

One object class may show large variations due to diverse illuminations, backgrounds and camera viewpoints. Traditional object detection methods often perform worse under unconstrained video environments. To address this problem, many modern approaches model deep hierarchical appearance representations for object detection. Most of these methods require a timeconsuming training process on large manual labelling sample set. In this paper, the proposed framework takes a remarkably different direction to resolve the multi-scene detection problem in a bottom-up fashion. First, a scene-specific objector is obtained from a fully autonomous learning process triggered by marking several bounding boxes around the object in the first video frame via a mouse. Here the human labeled training data or a generic detector are not needed. Second, this learning process is conveniently replicated many times in different surveillance scenes and results in particular detectors under various camera viewpoints. Thus, the proposed framework can be employed in multi-scene object detection applications with minimal supervision. Obviously, the initial scene-specific detector, initialized by several bounding boxes, exhibits poor detection performance and is difficult to improve with traditional online learning algorithm. Consequently, we propose Generative-Discriminative model to partition detection response space and assign each partition an individual descriptor that progressively achieves high classification accuracy. A novel online gradual optimized process is proposed to optimize the Generative-Discriminative model and focus on the hard samples.Experimental results on six video datasets show our approach achieves comparable performance to robust supervised methods, and outperforms the state of the art self-learning methods under varying imaging conditions.

Euler deconvolution method is the method of depth estimation which is best suited for anomalies caused by isolating and multiple anomalous sources. In the present study, algorithmic programs based on generalizing linear inverse theory, uses a least square sense to solve for Euler’s equation is being written. The Euler technique that can estimate the location of a simple body from measurements of the magnetic field could be applied to a long profile of measurements, by dividing the profile into the windows of consecutive measurements, each window providing a single estimate of depth and source location. Acceptable solutions for features of interest may involve some trial and error by adjusting the structural index and the window size. When all such measurements are plotted they tend to cluster around magnetization of geologic interest. Some indication of the source type can be gained by varying the structural index for any particular feature. Shallow features can be deconvolved well by using small window to reduce source interference. By using n = 1 and n = 1. 5, and deconvolved with small window sizes, our program yields good tight clustering and acceptable depths of the anomalous igneous body located along aeromagnetic profile in the south of Amenzi area, Inner Mongolia, North China. The depths obtained by using the structural index of n = 1. 5 varying between 700-900 m. The method yielded useful solutions with an acceptable depth estimate.

Background Lymphatic filariasis (LF) caused by Wuchereria bancrofti is present at high prevalence in some parts of Papua New Guinea. However, there has been no rigorous data-based representative assessment of nationwide prevalence of LF. The LF programme has been daunted by the scope of the problem, and progress on mass drug administration (MDA) has been slow and lacking in resources. Methods A systematic literature review identified LF surveys in Papua New Guinea between 1980 and 2011. Results were extracted by location, time period and test used (blood slide, immunochromatographic test (ICT) or Og4C3 ELISA) and combined by district. Three criteria schemes based on the Global Programme to Eliminate Lymphatic Filariasis guidelines, with modifications, were developed to classify and prioritize districts by prevalence level. Results of repeated surveys in the same sites were used to investigate the impact of MDA on LF prevalence over the time period. Results There were 312 distinct survey sites identified in 80 of the 89 districts over the 31-year period. The overall LF prevalence in the sites tested was estimated at 18.5 to 27.5% by blood slide for microfilariae (Mf), 10.1% to 12.9% by ICT and 45.4% to 48.8% by Og4C3. Biases in site selection towards areas with LF, and change in type of assay used, affected the prevalence estimates, but overall decline in prevalence over the time period was observed. Depending on the criteria used, 34 to 36 districts (population 2.7 to 2.9 million) were classed as high endemic (≥5% prevalence), 15 to 25 districts (1.7 to 1.9 million) as low endemic (

This paper describes a large scale control programme for falciparum malaria in Xinyang prefecture, China, from the early 1980s to 1992. Falciparum malaria, transmitted mainly by Anopheles anthropophagus, was epidemic in Gusi, Huangchuan, Shangcheng and Huaibin counties in the prefecture in the early 1980s, 2922 cases being reported in 1984. From 1985 to 1992, DDT residual spraying and the use of bed nets impregnated with pyrethroid insecticide were introduced for 2 consecutive years in areas at higher risk of P. falciparum infection, and then gradually extended to cover all the endemic areas over a period of 8 years. Malaria control was also carried out through the primary health care system in 4 counties, as had been done since the 1970s. As a result, no falciparum malaria case has been found since 1988 in spite of extensive surveillance, and vivax malaria has also decreased greatly. Repeated cross-sectional surveys showed that A. anthropophagus could not be found in most sites after 2 consecutive years of the vector control programme. Vector control was a major factor in the successful elimination of falciparum malaria and decreasing the incidence of P. vivax in the 4 counties.

A population-based case-control study to evaluate the protective effect of bed nets impregnated with pyrethroid insecticide and of vaccination against Japanese encephalitis was carried out in Gusi county, Henan province, China from June to September 1991; 50 cases and 100 matched controls were studied. Bed nets impregnated with pyrethroid insecticide greatly decreased the risk of infection among children under 10 years old, and vaccine efficacy was 78% (95% CI 16%–94%). We suggest that impregnated bed nets could be used as a quick response during outbreaks of Japanese encephalitis.

A community-based intervention trial was carried out to evaluate the effectiveness of alphamethrin-impregnated bed nets for control of Plasmodium vivax malaria and its vector in an area of moderate endemicity in southern Henan province, central China in 1990. Malaria incidence was significantly lower in the intervention group than in the comparison group (2.03 vs. 3.57 per 100 person-years at risk). The protective efficacy for malaria incidence was 43%. The prevalence of malaria parasitaemia among children under 10 years old in the intervention group was about one-quarter of that in the comparison group (0.93% vs. 3.25% and 0.71% vs. 1.96% after one and 4 months use of impregnated nets, respectively). Alphamethrin-impregnated bed nets had a mass killing effect on vector mosquitoes. The outdoor person-biting density of Anopheles anthropophagus and A. sinensis decreased by 70.3% and 29.3% respectively. The density of these 2 mosquito species found resting inside treated nets was close to zero. No side effect was found among users of impregnated bed nets. Impregnation with alphamethrin was more effective on polyester than on cotton netting and residual effects lasted at least one year. Use of alphamethrin is less expensive than permethrin and deltamethrin.

A retrospective investigation was conducted to evaluate the effectiveness of DDT residual indoor spraying and bed nets impregnated with pyrethroid insecticide for Japanese encephalitis control in southern Henan province, China. DDT residual indoor spraying had no effect on the incidence of Japanese encephalitis, but it was greatly reduced after the introduction of pyrethroid-impregnated bed nets. Only a small effect on outdoor biting densities of Culex tritaeniorhyncus was found, although the number of mosquitoes resting inside bed nets decreased markedly after the introduction of bed net impregnation.