0000000000297215

AUTHOR

Koki Ogura

showing 7 related works from this author

A discrete pulse group control-based series resonant inverter with complete ZCS-assisted inductors for consumer high frequency IH application

2017

This paper presents a pulse density modulated (PDM) voltage source high frequency series load resonant soft switching inverter (SRI) for the HF induction heated fixing roller in the energy saving copy and printing machines. The proposed simple and high efficiency SRI based on PDM control operation can achieve complete zero current soft switching for wide output power regulation ranges. In this work, its transient and steady-state operating principle are described and analyzed on the basis of high frequency PDM. The operating performances as power conversion efficiency, power losses analysis and temperature rising characteristics of this SRI are demonstrated and discussed through experimenta…

Materials science020209 energy020208 electrical & electronic engineeringAutomatic frequency controlEnergy conversion efficiency02 engineering and technologyInductorPower (physics)0202 electrical engineering electronic engineering information engineeringElectronic engineeringInverterVoltage sourceTransient (oscillation)Resonant inverter2017 IEEE 12th International Conference on Power Electronics and Drive Systems (PEDS)
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Spectrum Sensing in Cognitive Radio Using CNN-RNN and Transfer Learning

2022

Cognitive radio has been proposed to improve spectrum utilization in wireless communication. Spectrum sensing is an essential component of cognitive radio. The traditional methods of spectrum sensing are based on feature extraction of a received signal at a given point. The development in artificial intelligence and deep learning have given an opportunity to improve the accuracy of spectrum sensing by using cooperative spectrum sensing and analyzing the radio scene. This research proposed a hybrid model of convolution and recurrent neural network for spectrum sensing. The research further enhances the accuracy of sensing for low SNR signals through transfer learning. The results of modellin…

VDP::Teknologi: 500General Computer ScienceGeneral EngineeringGeneral Materials ScienceElectrical and Electronic EngineeringIEEE Access
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Simple Lossless Inductive Snubbers-Assisted Series Load Resonant Inverter Operating under ZCS-PDM Scheme for High-Frequency Induction Heating Fixed R…

2022

This paper presents a high-frequency pulse-density-modulated (PDM) soft-switching series load resonant inverter for use in induction heating (IH) fixed roller applications, which is used in copy and printing machines. The proposed simple high-frequency resonant inverter uses an asymmetrical pulse pattern PDM control scheme to achieve complete zero-current soft-switching commutations over a wide output range of input power regulation. Additionally, when the printer toner requires operation in very light load conditions, this causes difficulty in achieving zero-voltage or zero-current soft-switching operations in the IH high-frequency resonant inverters with pulse frequency modulation or puls…

Fluid Flow and Transfer ProcessesTechnologypulse density modulationQH301-705.5TPhysicsQC1-999Process Chemistry and TechnologyGeneral EngineeringEngineering (General). Civil engineering (General)induction heatingComputer Science ApplicationsVDP::Teknologi: 500high-frequency induction heating fixed rollerChemistryzero-current soft-switchinginduction heating; zero-current soft-switching; pulse density modulation; high-frequency induction heating fixed rollerGeneral Materials ScienceTA1-2040Biology (General)QD1-999InstrumentationApplied Sciences
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Battery technologies for electric vehicles

2017

This chapter gives a brief overview of the following types of vehicles: battery electric vehicle (BEV), plug-in hybrid electric vehicle (PHEV), and hybrid electric vehicle (HEV). It then provides a comprehensive summary of the electrochemical energy storage including Ni-MH battery, Li-ion battery, and advanced rechargeable battery. Battery chemistry is explained in a detailed manner including an abbreviated modelling approach. Also, the issues of battery-charging method, management, and monitoring are addressed. The chapter concludes with a discussion on battery cell voltage balancing and temperature monitoring in addition to the battery state-of-charge (SOC) estimation.

Battery (electricity)Temperature monitoringbusiness.product_categoryBattery cellbusiness.industryComputer scienceElectrical engineering02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnology01 natural sciences0104 chemical sciencesHardware_GENERALElectric vehicleBattery electric vehicleComputerSystemsOrganization_SPECIAL-PURPOSEANDAPPLICATION-BASEDSYSTEMSAutomotive battery0210 nano-technologybusinessElectrochemical energy storageVoltage
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Proactive Handoff of Secondary User in Cognitive Radio Network Using Machine Learning Techniques

2021

Spectrum management always appears as an essential part of modern communication systems. Handoff is initiated when the signal strength of a current user deteriorates below a certain threshold. In cognitive radio network, the perception of handoff is different due to the presence of two categories of users: certified/primary user and uncertified/secondary user. The reason for the spectrum handoff arises when the primary user (PU) returns to one of its band used by the secondary user. The spectrum handoff is of two types: reactive handoff and proactive handoff. There are certain limitations in reactive handoff, such as it suffers from prolonged handoff latency and interference. In the proacti…

Computer sciencebusiness.industryComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSDecision treeCommunications systemMachine learningcomputer.software_genreSpectrum managementRandom forestSupport vector machineCognitive radioHandoverMultilayer perceptronArtificial intelligencebusinesscomputer
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Frequency Regulation of Hybrid Power System by Optimized Adaptive Fuzzy PID Controller

2020

In this study, an adaptive fuzzy PID (AFPID) regulator has been proposed for frequency control of hybrid power system. For controller parameter optimization, an upgraded Whale Optimization Algorithm (WOA) has been employed. In the proposed Upgraded WOA (UWOA) technique, a cosine function is incorporated in the original WOA for determining control parameter to manage the position of whales throughout optimization procedure. Furthermore, scaling factors are employed in original WOA to adjust the travel of whales in search procedure. Proposed UWOA technique is employed to design an AFPID controller for frequency regulation of a hybrid power system It is demonstrated that UWOA technique out per…

business.product_categoryControl theoryComputer sciencePosition (vector)Frequency regulationAutomatic frequency controlElectric vehiclePID controllerTrigonometric functionsHybrid powerbusiness2020 5th International Conference on Smart and Sustainable Technologies (SpliTech)
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Blockchain based Device identification and authentication in a Smart Grid

2020

The power grid is a critical infrastructure of a country that needs protection and security. According to the report of the International Energy Agency, the electricity demand is constantly increasing the world over. Countries are moving towards green energy and efforts are being made to integrate these green energy into the main grid. Smart Grid will improve the reliability and efficiency of the grid by managing the energy demand. Cyber-attacks and cyber terrorism is also increasingly targeting the electrical grid. Intruders may try to gain access to the grid by exploiting the vulnerability of the grid. IEDs/devices are the endpoints of the network and they are the weakest link in the enti…

AuthenticationIdentification (information)Smart gridComputer scienceCryptographic hash functionComputer securitycomputer.software_genreGridElectrical gridcomputerCritical infrastructureVulnerability (computing)2020 5th International Conference on Smart and Sustainable Technologies (SpliTech)
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