• Journal of applied mathematics & informatics
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• v.39 no.3_4
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• pp.541-552
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• 2021

In this paper, we introduce q-sigmoid polynomials combining q-cosine function. We find several properties and identities of these polynomials which are related to sigmoid function using deep learning.

• The Korean Journal of Ecology
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• v.1 no.1
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• pp.3-10
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• 1977

The sigmoiod kinetics of mass-action in a biosystem have been studied by theoretical bases on the carrier hypothesis of influx and efflux of substrates. The sigmoid kinetic equations of assimilation and dissimilation rates indicate that each trophicfactor and each bio-factor behave according to the sigmoid kinetic equation and the bell shape case, and all of them are multiplicative. The general sigmoid kinetics of mass-action is given by the equation (30) which is determined by the total of the equation (28) of the assimilation rate and the equation (29) of the dissimilation rate. The sigmoid kinetic model of photosynthesis has been derived from the general equation of the sigmoid kinetics of mass-action.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.501-503
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• 1993

A circuit of sigmoid function for neural network is designed by using Piecewise Linear (PWL) method. The slope of sigmoid function can be adjusted to 2 and 0.25. Also the circuit presents both sigmoid function and its differential form. The circuits is simulated by using ViewLogic. Theoretical and simulated performance agree with 1.8 percent.

• Journal of Korean Neurosurgical Society
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• v.58 no.2
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• pp.150-154
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• 2015

Cerebral venous sinus thrombosis (CVST) following a closed head injury in pediatric patients is a rare condition, and an early spontaneous recanalization of this condition is extremely rare. A 10-year-old boy was admitted with a mild, intermittent headache and nausea five days after a bicycle accident. The brain computed tomography showed an epidural hematoma at the right occipital area with pneumocephalus due to a fracture of the occipital skull bone. The brain magnetic resonance imaging and the magnetic resonance venography demonstrated a flow signal loss from the right sigmoid sinus to the right jugular vein. The diagnosis was sigmoid sinus thrombosis, so close observations were selected as a treatment for the patient because of his gradually improving symptoms; however, he complained of vomiting 14 days the after conservative treatment. The patient was readmitted for a further examination of his symptoms. The laboratory and the gastroenterological examinations were normal. Due to concern regarding the worsening of the sigmoid sinus thrombosis, the brain magnetic resonance venography was rechecked and it revealed the recanalization of the venous flow in the sigmoid sinus and in the jugular vein.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.13 no.2
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• pp.199-203
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• 2010

Sigmoid volvulus may cause acute or subacute colonic obstruction. Excessive length of the sigmoid colon may be a contributing factor. Typically, the patient develops bilious vomiting and marked gaseous abdominal distension. We report a case of sigmoid volvulus in a 9-year-old boy who presented with recurrent, sudden onset abdominal pain, abdominal distension, and vomiting for 1 year, which was diagnosed by simple abdominal X-ray, barium enema, computed tomography, and colonoscopic examination. Colonoscopic reduction failed and a sigmoid colectomy with primary repair was performed. The intra-operative findings showed that the sigmoid colon was noted to be dilated, and redundant with a lax mesentery. Two clear areas of compression (proximal and distal) were present. After sigmoidectomy, the symptoms resolved. After 5 years of follow-up, he had no new symptoms.

• The Journal of the Korea Contents Association
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• v.10 no.4
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• pp.10-18
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• 2010

This paper presents a optimization of sigmoid activation function parameter using genetic algorithms and pattern recognition analysis in input space of two spirals benchmark problem. To experiment, cascade correlation learning algorithm is used. In the first experiment, normal sigmoid activation function is used to analyze the pattern classification in input space of the two spirals problem. In the second experiment, sigmoid activation functions using different fixed values of the parameters are composed of 8 pools. In the third experiment, displacement of the sigmoid function to determine the value of the three parameters is obtained using genetic algorithms. The parameter values applied to the sigmoid activation functions for candidate neurons are used. To evaluate the performance of these algorithms, each step of the training input pattern classification shows the shape of the two spirals.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.35.1-35
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• 2002

$\textbullet$ Sliding mode control (SMC) with nonlinear interpolation in variable boundary layer (VBL) is proposed $\textbullet$ A sigmoid function is used for nonlinear interpolation in VBL. $\textbullet$ The Parameter of the sigmoid function is tuned by fuzzy controller $\textbullet$ The choice of parameter for the sigmoid function is guided by FC. $\textbullet$ The parameter is continuously updated as boundary layer thickness varies. $\textbullet$ The proposed method hasbetter tracking performance than the conventional linear interpolation $\textbullet$ To demonstrate its performance the proposed control algorithm is applied to a nonlinear system.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.164.2-164
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• 2001

Sliding mode control (SMC) with variable nonlinear boundary layer is proposed. Two Fuzzy logic controllers (FLCs) are used to decide both boundary layer thickness and nonlinear interpolation using sigmoid function in the boundary layer. The nonlinear interpolation in the boundary layer suing FLC reduces stead state error and chattering. Sigmoid function is used to nonlinear interpolation in the boundary layer sigmoid function parameter with FLC. To demonstrate its performance, the Proposed control algorithm is applied to a simple nonlinear system.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1810-1815
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• 2003

Sliding mode control with nonlinear interpolation in the boundary layer is proposed. A modified sigmoid function is used for nonlinear interpolation in the boundary layer and its parameter is tuned by a fuzzy logic controller. The fuzzy logic controller that takes the distance between the system state and the sliding surface as its input guides the choice of parameter of the modified sigmoid function and the parameter is on-line tuned. Owing to the decreased thickness, the proposed method has better tracking performance than the conventional linear interpolation method. To demonstrate its performance, the proposed control algorithm is applied to a simple nonlinear system model.

• The Journal of Information Technology
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• v.4 no.3
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• pp.155-163
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• 2001

In this paper, we implemented sigmoid active function which make it difficult to design of the digital neuron networks. Therefore, we designed of the high speed processing of the sigmoid function in order to digital neural networks. we designed of the MAC(Multiplier and Accumulator) operation unit used residue number system without carry propagation for the high speed operation. we designed of MAC operation unit and sigmoid processing unit are proved that it could run of the high speed. On the simulation, the faster than 4.6ns on the each order, we expected that it adapted to the implementation of the high speed digital neural network.