• 제목/요약/키워드: Activation function

검색결과 1,479건 처리시간 0.029초

홉필드 신경회로망을 위한 단일전자 소자 (Single-Electron Devices for Hopfield Neural Network)

  • 유윤섭
    • 대한전자공학회논문지SD
    • /
    • 제45권6호
    • /
    • pp.16-21
    • /
    • 2008
  • 본 논문은 새롭게 제안된 단일전자 소자(single-electron device) 및 회로를 이용한 새로운 형태의 홉필드 신경회로망(Hopfield neural network)을 소개한다. 홉필드 신경회로망의 전기적 모델 내부에서 가변저항으로 사용되는 단일전자 시냅스(single-electron synapse)와 비선형 활성함수(nonlinear activation function)로 사용되는 두 단의 단일전자 인버터(single-electron inverter)를 몬테-칼로(Monte-Carlo) 방식의 단일전자 회로 시뮬레이터로 동작을 검증한다.

필발 추출물의 포도당 흡수능에 대한 효과 (Effects of Fructus Piperis Longi Extracts on Glucose Uptake in Adipocyte)

  • 김미성;권강범;송제호
    • 동의생리병리학회지
    • /
    • 제28권1호
    • /
    • pp.59-62
    • /
    • 2014
  • Glucose uptake plays a pivotal role in maintaining whole body glucose homeostasis in adipocytes and skeletal muscles. In the present study we have shown that Fructus Piperis Longi Extracts (FPLE) can stimulate glucose uptake in OP9 adipocytes. The increasing effects of FPLE on glucose uptake were inhibited by compound C pretreatment, which means that the glucose uptake effects by FPLE were carried out by AMP-activated protein kinase (AMPK) activation. Further studies revealed that FPLE stimulated glucose transport occurs through a mechanism involving extracellular signal-regulated kinase (ERK1/2) activation.

Discernment of Android User Interaction Data Distribution Using Deep Learning

  • Ho, Jun-Won
    • International Journal of Internet, Broadcasting and Communication
    • /
    • 제14권3호
    • /
    • pp.143-148
    • /
    • 2022
  • In this paper, we employ deep neural network (DNN) to discern Android user interaction data distribution from artificial data distribution. We utilize real Android user interaction trace dataset collected from [1] to evaluate our DNN design. In particular, we use sequential model with 4 dense hidden layers and 1 dense output layer in TensorFlow and Keras. We also deploy sigmoid activation function for a dense output layer with 1 neuron and ReLU activation function for each dense hidden layer with 32 neurons. Our evaluation shows that our DNN design fulfills high test accuracy of at least 0.9955 and low test loss of at most 0.0116 in all cases of artificial data distributions.

의사 가우시안 함수 신경망의 설계 (The Design of a Pseudo Gaussian Function Network)

  • 김병만;고국원;조형석
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
    • /
    • pp.16-16
    • /
    • 2000
  • This paper describes a new structure re create a pseudo Gaussian function network (PGFN). The activation function of hidden layer does not necessarily have to be symmetric with respect to center. To give the flexibility of the network, the deviation of pseudo Gaussian function is changed according to a direction of given input. This property helps that given function can be described effectively with a minimum number of center by PGFN, The distribution of deviation is represented by level set method and also the loaming of deviation is adjusted based on it. To demonstrate the performance of the proposed network, general problem of function estimation is treated here. The representation problem of continuous functions defined over two-dimensional input space is solved.

  • PDF

대칭형 상지 운동기구를 이용한 손목 운동 시 뇌 활성도 패턴 (Brain Activation During the Wrist Movement Using Symmetrical Upper Limb Motion Trainer)

  • 태기식;김사엽;송성재;이소영;박기영;손철호;김영호
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2004년도 추계학술대회 논문집
    • /
    • pp.1303-1306
    • /
    • 2004
  • We developed a symmetrical upper limb motion trainer for chronic hemiparetic subjects. This trainer enabled the practice of a forearm pronatio $n^ination and wrist flexion/extension. In this study, we have used functional magnetic resonance imaging(fMRI) with the developed symmetrical upper limb motion device, to compare brain activation patterns elicited by flexion/extension wrist movements of control and hemiparetic subject group. In control group, contralateral somatosensory cortex(SMC) and bilateral cerebellum were activated by dominant hand movement(Task 1), while bilateral movements by dominant hand(Task 2) activated the SMC in both cerebral hemispheres and ipsilateral cerebellum. However, in hemiparetic subject group, contralateral supplymentary motor area(SMA) was activated by unaffected hand movement(Task 1), while the activation of bilateral movements by unaffected hand(Task 2) showed only SMA in the undamaged hemisphere. This study, demonstrating the ability to accurately measure activation in both sensory and motor cortex, is currently being extended to patients in clinical applications such as the recovery of motor function after stroke.ke.

  • PDF

Role of ${\alpha}$-tocopherol in cellular signaling: ${\alpha}$-tocopherol inhibits stress-induced mitogen-activated protein kinase activation

  • Hyun, Tae-Kyung;Kumar, Kundan;Rao, Kudupudi Prabhakara;Sinha, Alok Krishna;Roitsch, Thomas
    • Plant Biotechnology Reports
    • /
    • 제5권1호
    • /
    • pp.19-25
    • /
    • 2011
  • Tocopherols belong to the plant-derived poly phenolic compounds known for antioxidant functions in plants and animals. Activation of mitogen-activated protein kinases (MAPK) is a common reaction of plant cells in defense-related signal transduction pathways. We report a novel non-antioxidant function of ${\alpha}$-tocopherol in higher plants linking the physiological role of tocopherol with stress signalling pathways. Pre-incubation of a low concentration of $50{\mu}M$ ${\alpha}$-tocopherol negatively interferes with MAPK activation in elicitor-treated tobacco BY2 suspension culture cells and wounded tobacco leaves, whereas pre-incubated BY2 cells with ${\alpha}$-tocopherol phosphate did not show the inhibitory effect on stimuli-induced MAPK activation. The decreased MAPK activity was neither due to a direct inhibitory effect of ${\alpha}$-tocopherol nor due to the induction of an inhibitory or inactivating activity directly affecting MAPK activity. The data support that the target of ${\alpha}$-tocopherol negatively regulates an upstream component of the signaling pathways that leads to stress dependent MAPK activation.

Mass production and application of activation tagged hairy root lines for functional genomic of secondary metabolism in ginseng

  • Choi, Dong-Woog;Chung, Hwa-Jee;Ko, Suk-Min;In, Dong-Soo;Song, Ji-Sook;Woo, Sung-Sick;Liu, Jang R.
    • Journal of Plant Biotechnology
    • /
    • 제36권3호
    • /
    • pp.294-300
    • /
    • 2009
  • Activation tagging that uses T-DNA vectors containing multimerized transcriptional enhancers from the cauliflower mosaic virus (CaMV) 35S gene is a powerful tool to determine gene function in plants. This approach has been successfully applied in screening various types of mutations and cloning the corresponding genes. We generated an activation tagged hairy root pool of ginseng (Panax ginseng C.A. Meyer) in an attempt to isolate genes involved in the biosynthetic pathway of ginsenoside (triterpene saponin), which is known as the major active ingredient of the root. Quantitative and qualitative variation of ginsenoside in activation tagged hairy root lines were profiled using LC/MS. Metabolic profiling data enabled selection of a specific hairy root line which accumulated ginsenoside at a higher level than other lines. The relative expression level of several genes of triterpene biosynthetic pathway in the selected hairy root line was determined by real time RT-PCR. Overall results suggest that the activation tagged ginseng hairy root system described in this study would be useful in isolating genes involved in a complex metabolic pathway from genetically intractable plant species by metabolic profiling.

DEVCS 모델을 사용한 심근 활성화과정의 시뮬레이션 (A Simulation of the Myocardium Activation Process using the Discrete Event Cell Space Model)

  • 김광년;정동근;김기련;최병철;이정태;전계록
    • 한국시뮬레이션학회논문지
    • /
    • 제13권4호
    • /
    • pp.1-16
    • /
    • 2004
  • The modelling and simulation of the activation process for the heart system is meaningful to understand special excitatory and conductive system in the heart and to study cardiac functions because the heart activation conducts through this system. This thesis proposes two dimensional cellular automaton(CA) model for the activation process of the myocardium and conducted simulation by means of discrete time and discrete event algorithm. In the model, cells are classified into anatomically similar characteristic parts of the heart and each of cells has a set of cells with preassigned properties. Each cell in this model has state variables to represent the state of the cell and has some state transition rules to change values of state variables executed by state transition function. The state transition rule is simple as follows. First, the myocardium cell at rest stay in passive state. Second, if any one of neighborhood cell in the myocardium cell is active state then the state is change from passive to active state. Third, if cell's state is an active then automatically go to the refractory state after activation phase. Four, if cell's state is refractory then automatically go to the passive state after refractory phase. These state transition is processed repeatedly in all cells through the termination of simulation.

  • PDF

Application of Modified Rapid Thermal Annealing to Doped Polycrystalline Si Thin Films Towards Low Temperature Si Transistors

  • So, Byung-Soo;Kim, Hyeong-June;Kim, Young-Hwan;Hwang, Jin-Ha
    • 한국재료학회지
    • /
    • 제18권10호
    • /
    • pp.552-556
    • /
    • 2008
  • Modified thermal annealing was applied to the activation of the polycrystalline silicon films doped as p-type through implantation of $B_2H_6$. The statistical design of experiments was successfully employed to investigate the effect of rapid thermal annealing on activation of polycrystalline Si doped as p-type. In this design, the input variables are furnace temperature, power of halogen lamps, and alternating magnetic field. The degree of ion activation was evaluated as a function of processing variables, using Hall effect measurements and Raman spectroscopy. The main effects were estimated to be furnace temperature and RTA power in increasing conductivity, explained by recrystallization of doped ions and change of an amorphous Si into a crystalline Si lattice. The ion activation using rapid thermal annealing is proven to be a highly efficient process in low temperature polycrystalline Si technology.