Evaluation of Annual Loads of Nutrients and Suspended Solids in Baltic Rivers

2003 ◽  
Vol 34 (3) ◽  
pp. 203-220 ◽  
Author(s):  
Pirkko Kauppila ◽  
Jari Koskiaho
Keyword(s):  
Suspended Solids ◽  
Reliable Method ◽  
Averaging Method ◽  
Correlation Method ◽  
Load Estimation ◽  
Calculation Methods ◽  
Simulation Experiments ◽  
Considerable Uncertainty ◽  
River Types ◽  
General Reliability

Estimation of pollutant fluxes through river systems calls for accurate and precise load estimation. However, considerable uncertainty is associated with these estimates due to diffuse loading, which sets high requirements not only on sampling frequencies but also on calculation methods. The aim was to examine the variation in load calculations and the reliability of the load estimates of total phosphorus, total nitrogen and suspended solids in 24 Baltic rivers varying in size and land-use characteristics. Reliability of the load estimates was tested by simulation experiments in the river Paimionjoki using a Monte Carlo procedure. The estimates calculated by the most reliable method were compared to the loads estimated by five other methods. The general reliability (RMSE) for P and SS was best by the correlation method and for N by the periodic method. Load calculations varied greatly depending both on the characteristics of the rivers and the calculation method. The flow-stratified method overestimated the P and SS loads by about 20% in large low-lake rivers. In small low-lake rivers, the overestimation was 10% and over 14% for P and SS, respectively. By contrast, the averaging method underestimated P and SS loads by 10% and 21% in small agricultural low-lake rivers. All the methods produced rather similar results for N in each of the river types.

scholarly journals Estimation Method of Fluorescent Donaldson Matrices Based on Multispectral Imaging Data

2020 ◽  
Vol 2020 (28) ◽  
pp. 227-231
Author(s):  
Shoji Tominaga
Keyword(s):  
Reliable Method ◽  
Multispectral Imaging ◽  
Estimation Method ◽  
Visible Range ◽  
Multiple Response ◽  
Imaging Data ◽  
Object Surface ◽  
Spectral Functions ◽  
Simulation Experiments ◽  
Image Acquisition System

This paper proposes a compact and reliable method to estimate the bispectral Donaldson matrices of fluorescent objects by using multispectral imaging data. We suppose that an image acquisition system allows multiple illuminant projections to the object surface and multiple response channels in the visible range. The Donaldson matrix is modeled as a twodimensional array with the excitation range (350, 700 nm) and the reflection and emission ranges (400, 700 nm). The observation model is described using the spectral sensitivities of a camera and the spectral functions of reflectance, emission, and excitation. The problem of estimating the spectral functions is formulated as a least squares problem to minimize the residual error of the observations and the roughness of the spectral functions. An iterative algorithm is developed to obtain the optimal estimates of the whole spectral functions. The performance of the proposed method is examined in simulation experiments using multispectral imaging data in detail.

Application of PCR to the Detection of Adenoviruses in Polluted Waters

1993 ◽  
Vol 27 (3-4) ◽  
pp. 235-241 ◽  
Author(s):  
R. Girones ◽  
A. Allard ◽  
G. Wadell ◽  
J. Jofre
Keyword(s):  
Environmental Samples ◽  
Suspended Solids ◽  
Reliable Method ◽  
Dna Amplification ◽  
Human Adenovirus ◽  
Glycine Buffer ◽  
Viral Particles ◽  
One Step ◽  
Polluted Waters ◽  
Amplification Reaction

A method for the detection of adenovirus in environmental samples has been developed. We tested several systems for concentrating viral particles by adding adenoviruses 2 and 12 to different sewage samples. The method selected was as follows: centrifugation of the sample in order to pellet adenovirus viral particles and all suspended solids, elution of the pelleted viruses by treatment with 0.25N glycine buffer pH 9.5, removal of solids from the sample by a short centrifugation and ultracentrifugation of the resulting supernatant. Elution with glycine buffer avoided inhibitors and showed more sensitivity than ultrasonication or filtration through a low binding protein filter to retain bacteria and suspended solids. Sewage samples were treated by this selected method and recovered viral particles were analyzed both by a two-step DNA amplification reaction and by infecting Hep-2 cells. About 50% of the samples were positive in a two-step PCR and these data were confirmed by tissue culture amplification and one step PCR. Two pairs of primers (external and nested) from the hexon region were used, which are able to detect human adenovirus from all subgenera. Although more studies are needed, the two-step PCR developed appears to be a quick and reliable method for adenovirus detection in environmental samples.

Multi-Channel Quantum Image Scrambling

2016 ◽  
Vol 20 (1) ◽  
pp. 163-170 ◽  
Author(s):  
Fei Yan ◽  
◽  
Yiming Guo ◽  
Abdullah M. Iliyasu ◽  
Zhengang Jiang ◽  
...  
Keyword(s):  
Quantum Computing ◽  
Information Hiding ◽  
Reliable Method ◽  
Color Image ◽  
Image Scrambling ◽  
Simulation Experiments ◽  
Quantum Image ◽  
Image Information ◽  
Geometric Transformations ◽  
Quantum Image Scrambling

Image scrambling is a technique used for confidential storage and transmission as well as for image information hiding. In this study, we propose a multi-channel quantum image scrambling method, which applies both color and geometric transformations of an image. This is a simple and reliable method for transforming a meaningful quantum image into a meaningless or disordered one. We performed two simulation experiments, which demonstrated the efficiency and flexibility of the proposed method. Previous studies mainly developed scrambling strategies for grayscale quantum images, whereas the proposed method is effective for the color image scrambling in the quantum computing domain.

The Slipper Shoe Mounting Hole Calculation Method Limitation Analysis for Spherical Swashplate Type Axial Piston Pump

2012 ◽  
Vol 246-247 ◽  
pp. 979-984
Author(s):  
San Mai Su ◽  
Chao Wang ◽  
Yong Qin Chen
Keyword(s):  
Calculation Method ◽  
Averaging Method ◽  
Piston Pump ◽  
Calculation Methods ◽  
Axial Piston Pump ◽  
Current Design ◽  
Motion Characteristics ◽  
Current Calculation ◽  
Axial Piston ◽  
Shape And Size

Take conical cylinder spherical swashplate type axial piston pump as research object, the calculation method limitation of slipper shoe mounting hole which located in mounting plate is analyzed. First of all ,the motion characteristics and the trace of slipper shoe is derived, then,based on above results, the sipper shoe mounting hole size current calculation methods in engineering and it’s limitations is analyzed,the conclusion is that: current design methods is parameter averaging method and also is an approximate method, in theory is not accurate and in engineering is unreasonable. In order to deign the slipper shoe mounting hole accurately, this paper recommends the most reasonable method is using slipper movement envelope to determine its shape and size.

Quantitative Diameter Measurements of Chromatin and TMV Fibers in the Freeze-Dried State

1988 ◽  
Vol 46 ◽  
pp. 170-171
Author(s):  
B. D. Athey ◽  
A. L. Stout ◽  
M. F. Smith ◽  
J. P. Langmore
Keyword(s):  
Reliable Method ◽  
Fiber Diameter ◽  
Quantitative Agreement ◽  
One Dimension ◽  
Fiber Axis ◽  
Two Dimensional ◽  
Fiber Density ◽  
Variable Diameter ◽  
Freeze Dried ◽  
Expected Values

Although there is general agreement that Inactive chromosome fibers consist of helically packed nucleosomes, the pattern of packing is still undetermined. Only one of the proposed models, the crossed-linker model, predicts a variable diameter dependent on the length of DNA between nucleosomes. Measurements of the fiber diameter of negatively-stained and frozen- hydrated- chromatin from Thyone sperm (87bp linker) and Necturus erythrocytes (48bp linker) have been previously reported from this laboratory. We now introduce a more reliable method of measuring the diameters of electron images of fibrous objects. The procedure uses a modified version of the computer program TOTAL, which takes a two-dimensional projection of the fiber density (represented by the micrograph itself) and projects it down the fiber axis onto one dimension. We illustrate this method using high contrast, in-focus STEM images of TMV and chromatin from Thyone and Necturus. The measured diameters are in quantitative agreement with the expected values for the crossed-linker model for chromatin structure

Application of cross correlation to HREM images of surfaces

1987 ◽  
Vol 45 ◽  
pp. 754-755
Author(s):  
D. E. Luzzi ◽  
L. D. Marks ◽  
M. I. Buckett
Keyword(s):  
Cross Correlation ◽  
A Priori ◽  
Matrix Material ◽  
Correlation Method ◽  
Accurate Knowledge ◽  
Complex Image ◽  
Fourier Filtering ◽  
The Matrix ◽  
Low Pass ◽  
Data Reduction Technique

As the HREM becomes increasingly used for the study of dynamic localized phenomena, the development of techniques to recover the desired information from a real image is important. Often, the important features are not strongly scattering in comparison to the matrix material in addition to being masked by statistical and amorphous noise. The desired information will usually involve the accurate knowledge of the position and intensity of the contrast. In order to decipher the desired information from a complex image, cross-correlation (xcf) techniques can be utilized. Unlike other image processing methods which rely on data massaging (e.g. high/low pass filtering or Fourier filtering), the cross-correlation method is a rigorous data reduction technique with no a priori assumptions.We have examined basic cross-correlation procedures using images of discrete gaussian peaks and have developed an iterative procedure to greatly enhance the capabilities of these techniques when the contrast from the peaks overlap.

Benefits from Computerized Adaptive Testing as Seen in Simulation Studies

1999 ◽  
Vol 15 (2) ◽  
pp. 91-98 ◽  
Author(s):  
Lutz F. Hornke
Keyword(s):  
Measurement Error ◽  
Computerized Adaptive Testing ◽  
Test Procedure ◽  
Adaptive Testing ◽  
Parameter Estimates ◽  
Simulation Studies ◽  
Computerized Adaptive Test ◽  
Item Banks ◽  
Item Parameters ◽  
General Reliability

Summary: Item parameters for several hundreds of items were estimated based on empirical data from several thousands of subjects. The logistic one-parameter (1PL) and two-parameter (2PL) model estimates were evaluated. However, model fit showed that only a subset of items complied sufficiently, so that the remaining ones were assembled in well-fitting item banks. In several simulation studies 5000 simulated responses were generated in accordance with a computerized adaptive test procedure along with person parameters. A general reliability of .80 or a standard error of measurement of .44 was used as a stopping rule to end CAT testing. We also recorded how often each item was used by all simulees. Person-parameter estimates based on CAT correlated higher than .90 with true values simulated. For all 1PL fitting item banks most simulees used more than 20 items but less than 30 items to reach the pre-set level of measurement error. However, testing based on item banks that complied to the 2PL revealed that, on average, only 10 items were sufficient to end testing at the same measurement error level. Both clearly demonstrate the precision and economy of computerized adaptive testing. Empirical evaluations from everyday uses will show whether these trends will hold up in practice. If so, CAT will become possible and reasonable with some 150 well-calibrated 2PL items.

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