Search results for "fuzzy"
showing 10 items of 747 documents
THERP and HEART integrated methodology for human error assessment
2014
Medical errors are one of the leading causes of death and injury in radiation therapy administration as reported in the literature. This point out an overall deficiency in management allowing patient treatment in the absence of suitable quality assurance processes. Clinical records of major accidental exposure events in radiotherapy show that there is a combination of factors contributing to the accident such as deficient staff training, lack of independent checks, lack of quality control procedures, and absence of overall supervision. Another finding is that training generally addresses only normal situations and does not prepare radiotherapy staff for unusual situations, resulting in a la…
Diversita’ spaziale del cloro residuo nelle reti di approvvigionamento idrico
2007
La qualità dell’acqua nelle reti di distribuzione può essere sensibilmente alterata da una serie di processi che si sviluppano sia lungo il sistema di adduzione che nella stessa rete di distribuzione. La riduzione della concentrazione di cloro, utilizzato per la disinfezione delle acque, può essere considerata un indice del progressivo deterioramento delle caratteristiche igieniche dell'acqua circolante in rete. La concentrazione del cloro, libero o combinato, è infatti strettamente legata alle reazioni che si sviluppano all’interno delle condotte. In questo lavoro particolare attenzione è rivolta alla identificazione della diversità spaziale del cloro residuo in rete. L’analisi viene condo…
GRANULAR-INFORMATION-BASED RISK ANALYSIS IN UNCERTAIN SITUATIONS
2006
In the real life almost all of the decisions that we have to make incorporate uncertainty about the future events. Assessment of the uncertainty and, thus, the risk that is inherent in these decisions models can be critical. It is even truer if we are talking about the possibility of negative impact on the environment. It is very important to assess all the environmental risks in a project if there is any hazard to the environment. In this paper the possibility of using granular information is considered. The main advantage of the granular information is that it can be used to assess risks in situations when information about future events is incomplete and imprecise. Moreover, we can use n…
FMECA Application in Tomotherapy: Comparison between Classic and Fuzzy Methodologies
2022
Accident analysis in radiotherapy highlighted the need to increase quality assurance (QA) programs by the identification of failures/errors with very low probability (rare event) but very severe consequences. In this field, a Failure Mode, Effects and Criticality Analysis (FMECA) technique, used in various industrial processes to rank critical events, has been met with much interest. The literature describes different FMECA methods; however, it is necessary to understand if these tools are incisive and effective in the healthcare sector. In this work, comparisons of FMECA methodologies in the risk assessment of patients undergoing treatments performed with helical tomotherapy are reported. …
Paysage et risque sanitaire - Le cas de l'echinococcose alvéolaire. Approche multiscalaire
2005
Echinococcus multilocularis is a parasite of public health importance causing the fatal zoonotic disease alveolar echinococcosis. The parasite's eggs are dispersed in the environment through the fox faeces. Epidemiological issues associated with the disease led to the monitoring of the endemic status in foxes in France and in Europe. Fox faeces collected in the field were tested for the presence of the parasite and assembled in a georeferenced database. GIS-assisted analysis investigated relationships between landscape characteristics and potential risk. Three scale levels were successively explored. In the french Doubs département located in a high endemicity area, binary logistic regressi…
Assessing the profitability of investment projects using ordered fuzzy numbers
2019
Wstęp: U podstaw rozważań leży stwierdzenie, że większość podejść do budżetowania kapitałowego ma charakter deterministyczny. W rzeczywistości problemowi budżetowania towarzyszy niepewność i ryzyko związane z przetwarzaniem nieprecyzyjnych danych. Uwzględnienie tej niepewności nie tylko pomaga lepiej zmierzyć efektywność projektów inwestycyjnych, ale także rozszerzyć zastosowanie metod budżetowania kapitałowego w warunkach rzeczywistych lub niepewnych. Głównym celem artykułu jest opracowanie nowatorskiego podejścia do oceny opłacalności projektu inwestycyjnego w warunkach niepewności. Metody: Prezentujemy nowatorskie podejście uwzględniające niepewność w ocenie opłacalności projektów inwest…
Podejście do analizy zaangażowania interesariuszy w projekcie wykorzystujące skierowane liczby rozmyte
2016
Celem artykułu jest przedstawienie autorskiego podejścia do zagadnienia szacowania zaangażowania interesariuszy w projekcie. W pracy zaprezentowano możliwości zastosowania aparatu matematycznego w postaci skierowanych liczb rozmytych do opisu parametrów oceny ich dynamiki zmian w cyklu życia projektu.
Fuzzy economic spaces
1980
Traditional spatial economic analysis is limited to the description of precise spaces. To say that an economic space is precise means: (1) that this space has, or else, has not given constituent characteristics and (2) that the agents located there prefer, or else, do not prefer one possible action to another. Proposition (1) implies that an economic space is perfectly delimited and that it can be clearly partitioned into homogeneous subspaces. Proposition (2) implies that economic agents undertake exact economic calculations and optimize, under rigid constraints of resource limitation, objective functions whose arguments are clearly defined. Thus, traditional spatial economic analysis is b…
Twister Tries
2015
Many commonly used data-mining techniques utilized across research fields perform poorly when used for large data sets. Sequential agglomerative hierarchical non-overlapping clustering is one technique for which the algorithms’ scaling properties prohibit clustering of a large amount of items. Besides the unfavorable time complexity of O(n 2 ), these algorithms have a space complexity of O(n 2 ), which can be reduced to O(n) if the time complexity is allowed to rise to O(n 2 log2 n). In this paper, we propose the use of locality-sensitive hashing combined with a novel data structure called twister tries to provide an approximate clustering for average linkage. Our approach requires only lin…
Cluster-Based RF Fingerprint Positioning Using LTE and WLAN Outdoor Signals
2015
In this paper we evaluate user-equipment (UE) positioning performance of three cluster-based RF fingerprinting methods using LTE and WLAN signals. Real-life LTE and WLAN data were collected for the evaluation purpose using consumer cellular-mobile handset utilizing ‘Nemo Handy’ drive test software tool. Test results of cluster-based methods were compared to the conventional grid-based RF fingerprinting. The cluster-based methods do not require grid-cell layout and training signature formation as compared to the gridbased method. They utilize LTE cell-ID searching technique to reduce the search space for clustering operation. Thus UE position estimation is done in short time with less comput…