scholarly journals APPROXIMATION OF THE CUT FUNCTION BY STANNARD AND RICHARD SIGMOID FUNCTIONS

2016 ◽  
Vol 109 (1) ◽  
Author(s):  
A. Iliev ◽  
N. Kyurkchiev ◽  
S. Markov
Keyword(s):  
Sigmoid Functions ◽  
Cut Function

scholarly journals Are the ‘Illnesses’ of Traditional Likert Scales Treatable?

2020 ◽  
Vol 24 (2) ◽  
pp. 120
Author(s):  
Zsuzsanna E. Tóth ◽  
Gábor Árva ◽  
Rita V. Dénes
Keyword(s):  
Customer Satisfaction ◽  
Organizational Performance ◽  
Rating Scale ◽  
Context Dependency ◽  
Managerial Decisions ◽  
Scale Yielding ◽  
Precise Representation ◽  
Viable Approach ◽  
Sigmoid Functions ◽  
The Membership Function

<p><strong>Purpose:</strong> The main aim of this paper is to introduce the development and the application of a fuzzy rating scale in measuring customer satisfaction which are to be demonstrated through a healthcare example in order to illustrate how the proposed methodology is able to enhance the reliability of traditional Likert scale-based evaluations.</p><p><strong>Methodology/Approach:</strong> The proposed methodology is built on fuzzy sets the membership function of which is composed of two sigmoid functions by applying Dombi’s conjunction operator. The possible ‘values’ of the linguistic variable expressing customer satisfaction are to be expressed by these functions which can also be linked to the level of organizational performance allowing the illustration of the mainly nonlinear relationship between the provided and perceived service performance.</p><p><strong>Findings:</strong> The application of the proposed fuzzy rating scale confirms its ability to reflect the unambiguity of human ratings as well as the context-dependency of ratings resulting in a more precise representation of human judgements.</p><p><strong>Research Limitation/implication:</strong> The presented methodology may be viewed as a viable approach in any kind of service quality evaluations where Likert-type scales are traditionally applied to handle its weaknesses.</p><strong>Originality/Value of paper:</strong> The proposed methodology is not only able to reflect the satisfaction of customers and the organizational performance simultaneously, but the expectations of customers related to the desired level of performance can also be incorporated into the establishment of the scale yielding to more reliably supported managerial decisions.

Activation Functions Defined on Higher-Dimensional Spaces for Approximation on Compact Sets with and without Scaling

2003 ◽  
Vol 15 (9) ◽  
pp. 2199-2226
Author(s):  
Yoshifusa Ito
Keyword(s):  
Fourier Transform ◽  
Activation Function ◽  
Continuous Functions ◽  
Activation Functions ◽  
Compact Sets ◽  
Higher Dimensional ◽  
Hidden Layer ◽  
The Fourier Transform ◽  
Increasing Function ◽  
Sigmoid Functions

Let g be a slowly increasing function of locally bounded variation defined on Rc, 1 ≤c≤d. We investigate when g can be an activation function of the hidden-layer units of three-layer neural networks that approximate continuous functions on compact sets. If the support of the Fourier transform of g includes a converging sequence of points with distinct distances from the origin, it can be an activation function without scaling. If and only if the support of its Fourier transform includes a point other than the origin, it can be an activation function with scaling. We also look for a condition on which an activation function can be used for approximation without rotation. Any nonpolynomial functions can be activation functions with scaling, and many familiar functions, such as sigmoid functions and radial basis functions, can be activation functions without scaling. With or without scaling, some of them defined on Rd can be used without rotation even if they are not spherically symmetric.

scholarly journals Simulated fishing experiments for predicting delayed mortality rates using reflex impairment in restrained fish

2007 ◽  
Vol 64 (8) ◽  
pp. 1535-1542 ◽  
Author(s):  
M. W. Davis
Keyword(s):  
Mortality Rates ◽  
Mortality Data ◽  
Second Phase ◽  
Fish Stocks ◽  
Fishing Vessels ◽  
Discard Mortality ◽  
Delayed Mortality ◽  
Mortality Predictors ◽  
Sigmoid Functions

Abstract Davis, M. W. 2007. Simulated fishing experiments for predicting delayed mortality rates using reflex impairment in restrained fish. – ICES Journal of Marine Science, 64: 1535–1542. Development of efficient methods to predict discard and escapee mortality in fishing operations is essential to the conservation of sensitive fish stocks. For a few fisheries, mortality data are available from fishing experiments in the field; these require long-term holding or monitoring of fish in tanks, cages, or tag and recapture experiments to detect delayed mortality. A different approach to predicting discard and escapee mortality is to use reflex action mortality predictors (RAMP) consisting of relationships between mortality and reflex impairment for species of interest. Fish were towed in a net in the laboratory and then either restrained in foam-lined holders and rapidly tested for reflex impairment five minutes after towing, or held for up to 60 days to determine delayed mortality. Delayed mortality occurred up to 20 days after towing. RAMP was related to mortality with biphasic sigmoid functions. As fishing stressors increased in intensity, the first phase showed an increase in RAMP with no concomitant mortality. In the second phase, RAMP continued to increase, while mortality became apparent and increased. The measurement of RAMP in restrained fish on board fishing vessels during experiments to predict discard mortality and in caged free swimming fish to predict escapee mortality is feasible and advisable.

scholarly journals Bipolar Log-Intensity-Variance Histogram Method for Local Image Patch Intensity Change Measurements

2019 ◽  
Vol 2019 ◽  
pp. 1-16
Author(s):  
Han Wang ◽  
Quan Shi ◽  
Zhihuo Xu ◽  
Ming Wei ◽  
Hanseok Ko
Keyword(s):  
Intensity Change ◽  
Image Patch ◽  
Fixed Position ◽  
Histogram Method ◽  
Probabilistic Measure ◽  
Object Movement ◽  
Image Patches ◽  
Intensity Changes ◽  
Sigmoid Functions ◽  
Local Image

For a fixed-position camera, the intensity changes of an image pixel are often caused by object movement or illumination change. This paper focuses on such a problem: given two adjacent local image patches, how can the causes of intensity change be determined? A bipolar log-intensity-variance histogram is proposed to describe the intensity variations on the chaos phase plot subspace. This is combined with two sigmoid functions to construct a probabilistic measure function. Experimental results show that the proposed measurements are more effective and robust than conventional methods to the cause of variation in image intensity.

System Identification Using Neural Networks with Parametric Sigmoid Functions

1995 ◽  
Vol 31 (3) ◽  
pp. 277-283 ◽  
Author(s):  
Mahmoud HASHEMINEJAD ◽  
Junichi MURATA ◽  
Kotaro HIRASAWA ◽  
Setsuo SAGARA
Keyword(s):  
Neural Networks ◽  
System Identification ◽  
Sigmoid Functions

Mathematical Models of Diuresis after Oral Administration of Tizolemide, Furosemide and Placebo to Healthy Adults

1981 ◽  
Vol 9 (1) ◽  
pp. 18-20
Author(s):  
A J Reyes ◽  
CE Cardiol ◽  
CP Biomat ◽  
W P Leary ◽  
C P Venter
Keyword(s):  
Oral Administration ◽  
Mathematical Models ◽  
Urine Volume ◽  
Mean Value ◽  
Healthy Adults ◽  
Healthy Male ◽  
Mean Values ◽  
Sigmoid Functions

Urine volumes and flows as functions of time after oral administration of placebo, furosemide 80 mg and tizolemide 100 mg to sixteen healthy male adults at 08.00 a.m. are described through mathematical models. Accumulated urine volumes after dosing, V, as functions of time, t, are accounted for by sigmoid functions and urine flows are described as dV/dt. No significant differences were found between the 24-hour urine volume mean values after furosemide (2457 ml) and tizolemide (2283 ml) and both were significantly higher than the corresponding mean value after placebo (1369 ml) (p < 0.001). Peak diuresis after dosing occurs about 1.5 hours for furosemide, 4 hours for tizolemide and 6 hours for placebo. Fourteen hours after dosing, urine volume amounts to 90% of the 24-hour urine volume after furosemide and to 76% after tizolemide, so that both substances may be regarded as diurnal diuretics.

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