Development of a species specific fouling index using principal component analysis of fluorescence excitation–emission matrices for the ultrafiltration of natural water and drinking water production

2011 ◽  
Vol 378 (1-2) ◽  
pp. 257-264 ◽  
Author(s):  
Ramila H. Peiris ◽  
Hector Budman ◽  
Christine Moresoli ◽  
Raymond L. Legge
Author(s):  
Petr Praus

In this chapter the principals and applications of principal component analysis (PCA) applied on hydrological data are presented. Four case studies showed the possibility of PCA to obtain information about wastewater treatment process, drinking water quality in a city network and to find similarities in the data sets of ground water quality results and water-related images. In the first case study, the composition of raw and cleaned wastewater was characterised and its temporal changes were displayed. In the second case study, drinking water samples were divided into clusters in consistency with their sampling localities. In the case study III, the similar samples of ground water were recognised by the calculation of cosine similarity, the Euclidean and Manhattan distances. In the case study IV, 32 water-related images were transformed into a large image matrix whose dimensionality was reduced by PCA. The images were clustered using the PCA scatter plots.


2014 ◽  
Vol 675-677 ◽  
pp. 960-963
Author(s):  
Li Feng Sun ◽  
Qing Jie Qi ◽  
Xiao Liang Zhao ◽  
Rui Feng Li

In order to effectively control pollution of sources of drinking water, improve the environmental quality of drinking water and guarantee the sanitation of drinking water, it is very important to assess water source quality. Main factors of drinking water were identified. Then principal component analysis was used to establish assessment model of drinking water, which could ensure that under the condition that the primitive data information was in the smallest loss, a small number of variables were used to replace the integrated multi-dimensional variables to simplify the data structure. The weightings of principal component were determinated as theirs pollution ratios. This paper was based on the theoretical study of principal component analysis, used the monitoring data on water quality of the main water resources in 2013 to evaluate and analyze the water quality of water resources. Analysis content included the main affecting factors, cause of pollution and the degree of pollution.The resulted showed that: the main affecting factors on water quality of Fo Si water source was CODMn, TP, fluoride.


2011 ◽  
Vol 11 (2) ◽  
pp. 179-185 ◽  
Author(s):  
R. H. Peiris ◽  
H. Budman ◽  
R. L. Legge ◽  
C. Moresoli

Natural river water is comprised of different foulant components such as natural organic matter and colloidal/particulate matter. Both individual and combined contributions of these foulant components results in different fouling behaviour. The ability to characterize these contributions that lead to reversible and irreversible membrane fouling would be beneficial for the implementation of fouling monitoring and control strategies for membrane-based drinking water treatment operations. A fluorescence excitation-emission matrix and principal component analysis-based approach was able to qualitatively estimate the accumulation of humic substances (HS)-, protein- and colloidal/particulate matter-like foulant components in membranes during the ultrafiltration (UF) of natural river water. A bench-scale flat sheet UF cross-flow set-up and successive permeation and membrane backwashing cycles were used. Analysis of the accumulation of these foulant components revealed that the increased levels of colloidal/particulate matter accumulation in the membranes appeared to have increased the extent of irreversible fouling by HS-like matter whereas lower irreversible fouling by protein-like matter was observed with increased colloidal/particulate matter accumulation. The results also indicate that the combined contributions by these foulants are important in the fouling of membranes during the UF of river water.


VASA ◽  
2012 ◽  
Vol 41 (5) ◽  
pp. 333-342 ◽  
Author(s):  
Kirchberger ◽  
Finger ◽  
Müller-Bühl

Background: The Intermittent Claudication Questionnaire (ICQ) is a short questionnaire for the assessment of health-related quality of life (HRQOL) in patients with intermittent claudication (IC). The objective of this study was to translate the ICQ into German and to investigate the psychometric properties of the German ICQ version in patients with IC. Patients and methods: The original English version was translated using a forward-backward method. The resulting German version was reviewed by the author of the original version and an experienced clinician. Finally, it was tested for clarity with 5 German patients with IC. A sample of 81 patients were administered the German ICQ. The sample consisted of 58.0 % male patients with a median age of 71 years and a median IC duration of 36 months. Test of feasibility included completeness of questionnaires, completion time, and ratings of clarity, length and relevance. Reliability was assessed through a retest in 13 patients at 14 days, and analysis of Cronbach’s alpha for internal consistency. Construct validity was investigated using principal component analysis. Concurrent validity was assessed by correlating the ICQ scores with the Short Form 36 Health Survey (SF-36) as well as clinical measures. Results: The ICQ was completely filled in by 73 subjects (90.1 %) with an average completion time of 6.3 minutes. Cronbach’s alpha coefficient reached 0.75. Intra-class correlation for test-retest reliability was r = 0.88. Principal component analysis resulted in a 3 factor solution. The first factor explained 51.5 of the total variation and all items had loadings of at least 0.65 on it. The ICQ was significantly associated with the SF-36 and treadmill-walking distances whereas no association was found for resting ABPI. Conclusions: The German version of the ICQ demonstrated good feasibility, satisfactory reliability and good validity. Responsiveness should be investigated in further validation studies.


Sign in / Sign up

Export Citation Format

Share Document