Fuzzy set theory based methodology for the analysis of measurement uncertainties in river discharge and stage

2010 ◽  
Vol 37 (3) ◽  
pp. 429-440 ◽  
Author(s):  
Rajesh R. Shrestha ◽  
Slobodan P. Simonovic
Keyword(s):  
Set Theory ◽  
Fuzzy Set ◽  
Fuzzy Set Theory ◽  
Velocity Measurement ◽  
Discharge Measurement ◽  
Sources Of Uncertainty ◽  
Fuzzy Aggregation ◽  
Combined Uncertainty ◽  
Discharge Measurements

The discharge and stage measurements in a river system are characterized by a number of sources of uncertainty, which affects the accuracy of a rating curve established from measurements. This paper presents a fuzzy set theory based methodology for consideration of different sources of uncertainty in the stage and discharge measurements and their aggregation into a combined uncertainty. The uncertainty in individual measurements of stage and discharge is represented using triangular fuzzy numbers, and their spread is determined according to the International Organization for Standardization (ISO) standard 748 guidelines. The extension principle based fuzzy arithmetic is used for the aggregation of various uncertainties into overall stage–discharge measurement uncertainty. In addition, a fuzzified form of ISO 748 formulation is used for the calculation of combined uncertainty and comparison with the fuzzy aggregation method. The methodology developed in this paper is illustrated with a case study of the Thompson River near Spences Bridge in British Columbia, Canada. The results of the case study show that the selection of number of velocity measurement points on a vertical is the largest source of uncertainty in discharge measurement. An increase in the number of velocity measurement points provides the most effective reduction in the overall uncertainty. The next most important source of uncertainty for the case study location is the number of verticals used for velocity measurements. The study also shows that fuzzy set theory provides a suitable methodology for the uncertainty analysis of stage–discharge measurements.

scholarly journals Application of Fuzzy Set Theory and SPOT Satellite Images in Site Selection of Public Libraries (Case Study: Saqqez City, Iran)

2013 ◽  
Vol 6 (6) ◽  
pp. 1122-1128 ◽  
Author(s):  
Heydar Dashti Nasserabadi ◽  
Himan Shahabi ◽  
Soroush Keihanfard ◽  
Darush Rahim Mashahi ◽  
Mohammadreza Khodakarami
Keyword(s):  
Set Theory ◽  
Fuzzy Set ◽  
Fuzzy Set Theory ◽  
Site Selection ◽  
Satellite Images ◽  
Public Libraries ◽  
Selection Of

Decision Making in Medical Diagnosis via Distance Measures on Interval Valued Fuzzy Sets

2017 ◽  
Vol 6 (4) ◽  
pp. 63-83 ◽  
Author(s):  
Palash Dutta
Keyword(s):  
Set Theory ◽  
Fuzzy Set ◽  
Fuzzy Set Theory ◽  
Medical Diagnosis ◽  
Intuitionistic Fuzzy Set ◽  
Distance Measures ◽  
Medical Documentation ◽  
Interesting Area ◽  
Interval Valued

The uncertain and sometimes vague, imprecise nature of medical documentation and information make the field of medical diagnosis is the most important and interesting area for applications of fuzzy set theory (FST), intuitionistic fuzzy set (IFS) and interval valued fuzzy set (IVFS). In this present study, first resemblance between IFS and IVFS has been established along with reviewed some existing distance measures for IFSs. Later, an attempt has been made to derive distance measures for IVFSs from IFSs and establish some properties on distance measures of IVFSs. Finally, medical diagnosis has been carried out and exhibits the techniques with a case study under this setting.

scholarly journals An Analysis of Urbanisation Dynamics with the Use of the Fuzzy Set Theory—A Case Study of the City of Olsztyn

2020 ◽  
Vol 12 (11) ◽  
pp. 1784 ◽  
Author(s):  
Andrzej Biłozor ◽  
Iwona Cieślak ◽  
Szymon Czyża
Keyword(s):  
Land Use ◽  
Urban Development ◽  
Set Theory ◽  
Fuzzy Set ◽  
Fuzzy Set Theory ◽  
Urban Areas ◽  
Structural Changes ◽  
Urban Core ◽  
Peripheral Areas

Quantitative, qualitative and structural changes in land use that occur in a given location over time are a manifestation and a measure of urban development. Urbanisation is a process of spatial diffusion that spreads from the urban core to peripheral areas. Urban development is linked with human activities in a specific location and in a given period of time. In the context of spatial management, urbanisation is a process where less intensive land-use types are replaced by more intensive forms of land use. The demand for new land for residential development, the search for alternative locations for housing construction and the development of sustainable land management plans require new methods that support decision-making in the process of land conversion in peri-urban areas. The aim of this study was to develop a methodology for identifying and localising the boundaries of urban development with the use of the fuzzy set theory and to analyse the rate of changes in land use based on data for 2005–2010–2017. The proposed method supports the identification and localisation of urbanised areas and an evaluation of the degree of urbanisation in the interval [0,1]. The case study was conducted in the Polish city of Olsztyn.

scholarly journals Dependable estimations for education quality using fuzzy logic based strategy a case study (University of Kufa)

2020 ◽  
Vol 17 (1) ◽  
pp. 472
Author(s):  
Adel Al Janabi ◽  
Ehsan Ali Kareem ◽  
Radhwan Hussein Abdulzhraa Al Sagheer
Keyword(s):  
Fuzzy Logic ◽  
Set Theory ◽  
Fuzzy Set ◽  
Fuzzy Set Theory ◽  
Education Quality ◽  
Assessment Strategy ◽  
Process Technique ◽  
Training Area

<span>The consideration that the Iraqi community has concentrated on the training area has delivered another college responsibility routed to superiority viewpoints for all training connected facilities. In truth, a superiority arranged facility necessitates perfection in the structure and arranging of facility exercises, in addition to amid its conveying for the received facility execution assessment strategy. In any case, considering that facility execution assessments are profoundly founded on partners’ decisions, they can be described by conceivable vulnerabilities identified with deficiency for incomplete obliviousness, imprecision for subjectivity and even dubiousness. In this way, underneath these circumstances, temperamental outcomes can be acquired by broadly measured facility investigation strategies. This paper is a strategy dependent an ongoing augmentation of ServQual display and it utilizes a consolidated way of Fuzzy Set Theory of command process technique that is proposed to adequately deal with vulnerability in facility execution examinations. Specifically, Fuzzy Set Theory is measured to manage vulnerability, while AHP strategy is embraced as device to appraise the significance loads of key facility characteristics. In this way, the key investigation of the facility esteem tree identified with the program in University of Kufa is made by using the planned strategy. The completed facility examination permits the most impacting facility execution components to be caught and remarked. At last, acquired outcomes demonstrate that the teachers' view of facility quality definitively impacts by large facility execution level. </span>

scholarly journals Automation of Measuring Actual Productivity of Earthwork in Urban Area, a Case Study from Montreal

Buildings ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 178
Author(s):  
Adel Alshibani
Keyword(s):  
Urban Area ◽  
Set Theory ◽  
Fuzzy Set ◽  
Fuzzy Set Theory ◽  
Google Earth ◽  
Medium Size ◽  
Accurate Estimation ◽  
Gps Data ◽  
Simulation Based

The construction of a new facility in an urban area, such as a downtown area, involves considerable earthwork excavation most of the time. Measuring the actual productivity of earthwork operations that involve heavy machinery can be a complex task for project managers. The complexity contributes to the impact of the many factors involved, the required accuracy, and the uncertainties associated with such operations. Traditionally, measuring actual productivity is carried out manually by measuring the actual quantities of the excavated earth. Measuring actual productivity manually is time-consuming and not necessarily accurate. The paper presents a case study project in Montreal to investigate the application of a developed methodology that is affordable for small to medium size contractors. It integrates the GPS and fuzzy set theory as an alternate effective methodology for measuring actual onsite productivity during the construction stage in an urban area. The developed methodology combines GPS data that are collected in near real time, fuzzy set theory (FST), and Google Earth. FST is used to define the variability and uncertainty which exists in the duration of the main activities of the earthwork (loading, traveling, dumping, and returning). Google Earth is used for graphical presentation and to store the collected GPS data of the moving hauling units. The productivity estimated by the developed methodology was compared with that provided by a simulation-based model, in which the collected GPS data are used to define the duration of earthmoving moving operations, and with that measured manually by contractor. The developed methodology proves that the utilization of GPS data and FST can yield a more accurate estimation of onsite actual productivity compared to that provided by simulation-based approaches, but in much a simpler way regarding the computation effort and time.

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