The releasing characteristics of phosphorus, nitrogen compounds, organics, and some metal cations during thermal treatment of excess sludge were investigated. It was found that during heating not only phosphorus, but ...
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The releasing characteristics of phosphorus, nitrogen compounds, organics, and some metal cations during thermal treatment of excess sludge were investigated. It was found that during heating not only phosphorus, but also nitrogen compounds, organics, and some metal cations could be released in abundance. The maximum orthophosphate （ortho-P） release of about 90 mg/L in concentration was observed at 50℃ in 1 h. Except for volatile fatty acids （VFAs）, comparatively little total nitrogen （TN）, total organic carbon （TOC）, and metal cations were released at the same time. Such results might favor further process of phosphorus recovery. VFAs were considerably released only at 50℃. Acetic, butyric, and propionic acid were the most abundant components in turn and their releasing profiles exhibited good linear relationship with time （R2 = 0.9977, 0.9624, and 0.8908, respectively）. The concentrations of Mg^2＋ and K^＋ increased with time and temperature during thermal treatment, but Ca^2＋ decreased. The release of Mg^2＋ and K^＋ agreed well with TP release （R^2 = 0.9892 and 0.9476, respectively）. Temperature in the experimental range had very little impact on the linear relationships, especially of Mg^2＋. Moreover, the parameter of mixed liquor suspended solids （MLSS） was found to be an important factor for thermal sludge treatment as the released ortho-P and total phosphorus （TP） at 50℃ increased more than one-fold when MLSS was increased from 4000 to 8000 mg/L.
In designing a focused crawler, the choice of strategy for prioritizing unvisited URLs is vital. The text surrounding a link or the link context on the HMTL page is a good summary of the target page. This paper invest...
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In designing a focused crawler, the choice of strategy for prioritizing unvisited URLs is vital. The text surrounding a link or the link context on the HMTL page is a good summary of the target page. This paper investigates some alternative methods and advocates that the link-context derived from reference page's HTML tag tree can provide a wealth of illumination for domain-specific web resource discovery guided by SVM classifier with uneven margins, which is particularly helpful for small training datasets. Little work has been done to utilize the beneficial link context information about the seed URLs. In order that crawler can acquire enough illumination from link-context, we initially look for some referring pages by traversing backward from seed URLs. The method collects this kind of resources beforehand and then uses it to steer resource discovery. A comprehensive experiment has been conducted using multiple crawls over 10 topics covering thousands of pages allowing us to derive statistically strong results.
A new 3D reconstruction algorithm based on particle swarm optimization (PSO) is proposed. This is the first time to introduce PSO to the multi-views problem. The proposed algorithm designs a scheme to represent the 3D...
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A new 3D reconstruction algorithm based on particle swarm optimization (PSO) is proposed. This is the first time to introduce PSO to the multi-views problem. The proposed algorithm designs a scheme to represent the 3D parameters using a particle. Then the PSO algorithm is used to search the solution space and optimizes the fitness function. Finally, the algorithm can efficiently get the correct solution with less time and less complexity. Additionally, some details of implement are discussed which influence the performance of the algorithm. Experiments and comparisons are given in real data. The accuracy of the recovered solution is compared to the existing algorithms and outperformed them.
In this paper, an economical cascadic multigrid method is proposed. Compared with the usual cascadic multigrid method developed by Bornemann and Deuflhard, the new one requires less iterations on each level, especiall...
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In this paper, an economical cascadic multigrid method is proposed. Compared with the usual cascadic multigrid method developed by Bornemann and Deuflhard, the new one requires less iterations on each level, especially on the coarser grids. Many operations can be saved in the new cascadic multigrid algorithms. The main ingredient is the control of the iteration numbers on the each level to preserve the accuracy without over iterations. The theoretical justification is based on the observations that the error reduction rate of an iteration scheme in terms of the smoothing property is no longer accurate while the iteration number is big enough. A new formulae of the error reduction rate is employed in our new algorithm. Numerical experiments are reported to support our theory.
The temperature of powder bed is very important for selective laser sintering system(SLS),because it directly affects the quality of ***,the temperature of powder bed should alter according to the slicing section cont...
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The temperature of powder bed is very important for selective laser sintering system(SLS),because it directly affects the quality of ***,the temperature of powder bed should alter according to the slicing section contour of model in order to ensure that the integration is successful and ***,the temperature of powder bed should change with shape of CAD model at different *** paper illuminates how to distinguish the slicing contour loops from adjacent *** this way,the temperature can be adaptively adjusted with altering of the sectional contours.
This paper describes a region-based retrieval system based on graph-cuts and global/local feature. We also use dynamic partial function (DPF), indexing by locality sensitive hashing (LSH) and learning feedback for imp...
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This paper describes a region-based retrieval system based on graph-cuts and global/local feature. We also use dynamic partial function (DPF), indexing by locality sensitive hashing (LSH) and learning feedback for improving system performance. Such a system is useful for finding a sub-object from a large image database. In order to obtain the sub-object from a sample image, we propose an efficient graph-cuts segmentation method to cut out the object. The system utilizes the segmentation results to capture the higher-level concept of images and gets a stable and accurate result. Also the feedback method is efficient. Experimental and comparison results, which are performed using a general purpose database containing 5,000 images, are encouraging.
Signed network is an important kind of complex network, which includes both positive relations and negative relations. Communities of a signed network are defined as the groups of vertices, within which positive relat...
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Signed network is an important kind of complex network, which includes both positive relations and negative relations. Communities of a signed network are defined as the groups of vertices, within which positive relations are dense and between which negative relations are also dense. Being able to identify communities of signed networks is helpful for analysis of such networks. Hitherto many algorithms for detecting network communities have been developed. However, most of them are designed exclusively for the networks including only positive relations and are not suitable for signed networks. So the problem of mining communities of signed networks quickly and correctly has not been solved satisfactorily. In this paper, we propose a heuristic algorithm to address this issue. Compared with major existing methods, our approach has three distinct features. First, it is very fast with a roughly linear time with respect to network size. Second, it exhibits a good clustering capability and especially can work well with complex networks without well-defined community structures. Finally, it is insensitive to its built-in parameters and requires no prior knowledge.
Plan recognition,the inverse problem of plan synthesis,is important wherever a system is expected to produce a kind of cooperative or competitive *** plan recognizers,however,suffer the problem of acquisition and hand...
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Plan recognition,the inverse problem of plan synthesis,is important wherever a system is expected to produce a kind of cooperative or competitive *** plan recognizers,however,suffer the problem of acquisition and hand-coding a larger plan *** paper is aims to show that modern planning techniques can help build plan recognition systems without suffering such ***,we show that the planning graph,which is an important component of the classical planning system Graphplan,can be used as an implicit,dynamic planning library to represent actions,plans and *** also show that modern plan generating technology can be used to find valid plans in this *** this sense,this method can be regarded as a bridge that connects these two research *** and theoretical results also show that the method is efficient and scalable.
Previous methods of volume rendering are very slow and thus impractical. We present volume rendering based on marching cubes iso-surfacing and transfer function. For an iso-surface, we divide the voxels into logical c...
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Previous methods of volume rendering are very slow and thus impractical. We present volume rendering based on marching cubes iso-surfacing and transfer function. For an iso-surface, we divide the voxels into logical cubes according to a predefined threshold value, the tangent planes and normal vectors at each voxel are calculated and the normal vectors are orientated to the outside of surface based on wide first searching (WFS), and the 3D surface model is then obtained using marching cubes. Transfer function is used to specify the optical properties for volume rendering technology. We employ a 2D function. The end-user interacts with a set of direct manipulation widgets (triangles and rectangles). Each widget precisely corresponds to a different material and widgets are blended automatically to compute an overall transfer function. Compared to traditional techniques, the overall specification process takes a fraction of the time.
fouling online in an anaerobic membrane bioreac-tor(AMBR).Short-term running experiments were carried out under different operating conditions to explore feasible ultrasonic *** experimental results indicated that whe...
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fouling online in an anaerobic membrane bioreac-tor(AMBR).Short-term running experiments were carried out under different operating conditions to explore feasible ultrasonic *** experimental results indicated that when the crossflow velocity was more than 1.0 m/s,mem-brane fouling could be controlled effectively only by hydro-dynamic methods without *** ultrasound was applied,an ultrasonic power range of 60-150 W was suitable for the membrane fouling control in the experimental *** experimental results showed that the membrane fouling was controlled so well that membrane filtration resistance(ΣR)could stay at 5×10^(11)m^(−1) for more than a week with the crossflow velocity of 0.75 m/s,which equaled the effect of crossflow velocity of more than 1.0 m/s without ultrasound.
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