• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.6
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• pp.539-545
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• 2013

In this paper, a behavioral current-voltage model with intermediate states is proposed for analog applications of unipolar resistive memories, where intermediate resistance values between SET and RESET state are used to store analog data. In this model, SET and RESET behaviors are unified into one equation by the blending function and the percentage volume fraction of each region is modeled by the Johnson-Mehl-Avrami (JMA) equation that can describe the time-dependent phase transformation of unipolar memory. The proposed model is verified by the measured results of $TiO_2$ unipolar memory and tested by the SPECTRE circuit simulation with CMOS read and write circuits for unipolar resistive memories. With the proposed model, we also show that the behavioral model that combines the blending equation and JMA kinetics can universally describe not only unipolar memories but also bipolar ones. This universal behavioral model can be useful in practical applications, where various kinds of both unipolar and bipolar memories are being intensively studied, regardless of polarity of resistive memories.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.431-434
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• 2008

The physical OLED analog behavioral model for SPICE simulation has been described using Verilog-A language. The model is based on the carrier-balance between the hole and electron injected through Schottky barrier at anode and cathode. The accuracy of this model was examined by comparing with the results from device simulation.

• Journal of information and communication convergence engineering
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• v.9 no.1
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• pp.74-77
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• 2011

PSPICE modeling of a commercial LED driver IC (TOP245P) and PC817A optocoupler is proposed for the switch-mode power supply (SMPS) (applicable to LED driver) design and simulation. An analog behavioral model of the TOP245P IC including the shunt regulator, under-voltage(UV) detection, over-voltage(OV) shut-down and SR flip-flop is developed by using PSPICE. The empirical equation of PC817A current transfer ratio (CTR) is fitted from the datasheet of PC817A. Two types of SMPSs are simulated with the averaged-model and switching-model. The simulation results by the proposed PSPICE models are in good agreement with those in the data sheet and an experimental data.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1212-1215
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• 2009

The theoretical equations for J-V characteristics in an OLED was derived according to the internal carrier emission equation based on a diffusion model at Schottky barrier contact and the mobility equation based on the Pool-Frenkel model. The J-V characteristics of OLED are presented using a behavioral model for analog systems (Verilog-A language), and the accuracy of this model was verified by comparing with the device simulation results.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.3
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• pp.122-129
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• 2001

Exact simulation of conducted EMI in switched mode power supplies is proposed. In order to achieve exact simulation, PSPICE active component ABM model and modified transformer model are proposed. Each model parameter is extracted from measurements and data-books. PSPICE simulation results with high frequency PCB pattern model are accordant with EMI measurements for a 50[W] isolated flyback converter. EMI relations of each component and EMI patterns are analyzed.

• The Journal of Society for e-Business Studies
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• v.7 no.1
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• pp.87-106
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• 2002

The behavioral and dynamic implications of an ERP implementation/installation are, to say the least, not well understood. Getting the switches set to enable the ERP software to go live is becoming straightforward. The really difficult part is understanding all of the dynamic interactions that accrue as a consequence. Dynamic causal and connectionist models are employed to facilitate an understanding of the dynamics and to enable control of the information-enhanced processes to take place. The connectionist model ran be analyzing (behind the scenes) the information accesses and transfers and coming If some conclusions about strong linkages that are getting established and what the behavioral implications of those new linkages and information accesses we. Ultimately, the connectionist model will come to an understanding of the dynamic, behavioral implications of the larger ERP implementation/installation per se. The underlying connectionist model will determine information transfers and workflow. Once a map of these two infrastructures is determined by the model, it becomes a relatively easy job for an analyst to suggest improvements in both. Connectionist models start with analog object structures and then use learning to produce mechanisms for managerial problem diagnoses. These mechanisms are neural models with multiple-layer structures that support continuous input/output. Based on earlier work performed and published by the author[10][11], a Connectionist ReasOning and LEarning System(CROLES) is developed that mimics the real-world reasoning infrastructure. Coupled with an explanation subsystem, this system can provide explanations as to why a particular reasoning structure behaved the way it did. Such a system operates in the backgmund, observing what is happening as every information access, every information response coming from each and every intelligent node (whether natural or artificial) operating within the ERP infrastructure is recorded and encoded. The CROLES is also able to transfer all workflows and map these onto the decision-making nodes of the organization.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.1876-1878
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• 1998

For an analysis and simulation of the conducted EMI of switching converters, an accurate simulation model for MOSFET is needed. This paper presents a new modeling approach, which incorporates DC output characteristics and AC dynamics especially the parasitic capacitances. It uses Pspice ABM(Analog Behavioral Model) and the MOSFET parameters can be obtained from the Data sheet in the frequency range of interest for EMI analysis. The model verified with an experimental setup and the EMI for a test converter is analyzed with respect to the MOSFET switching waveforms.

• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.222-223
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• 2010

TOP245P driver IC modeling technique are proposed for the LED Driver design. Analog behavioral model of TOP245P IC including the shunt regulator, under-voltage(UV) detection, over-voltage(OV) shut-down and SR flip-flop is developed by using PSPICE. The averaged-model and switching-model is applied to the LED driver simulation. The simulation results by the proposed TOP245P IC modeling technique are in good agreement with that in the data sheet and an experiment data.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.6
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• pp.679-688
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• 2018

Autism spectrum disorders (ASDs) are neurodevelopmental disorders that share behavioral features, the results of numerous studies have suggested that the underlying causes of ASDs are multifactorial. Behavioral and/or neurobiological analyses of ASDs have been performed extensively using a valid model of prenatal exposure to valproic acid (VPA). Abnormal synapse formation resulting from altered neurite outgrowth in neural progenitor cells (NPCs) during embryonic brain development has been observed in both the VPA model and ASD subjects. Although several mechanisms have been suggested, the actual mechanism underlying enhanced neurite outgrowth remains unclear. In this study, we found that VPA enhanced the expression of brain-derived neurotrophic factor (BDNF), particularly mature BDNF (mBDNF), through dual mechanisms. VPA increased the mRNA and protein expression of BDNF by suppressing the nuclear expression of methyl-CpG-binding protein 2 (MeCP2), which is a transcriptional repressor of BDNF. In addition, VPA promoted the expression and activity of the tissue plasminogen activator (tPA), which induces BDNF maturation through proteolytic cleavage. Trichostatin A and sodium butyrate also enhanced tPA activity, but tPA activity was not induced by valpromide, which is a VPA analog that does not induce histone acetylation, indicating that histone acetylation activity was required for tPA regulation. VPA-mediated regulation of BDNF, MeCP2, and tPA was not observed in astrocytes or neurons. Therefore, these results suggested that VPA-induced mBDNF upregulation was associated with the dysregulation of MeCP2 and tPA in developing cortical NPCs.