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IMPROVEMENT OF COMBUSTION BY MULTI-STAGE IMPINGING INJECTION USING NORMAL DODECANE AND NORMAL HEXADECANE
Get PDFIn recent years, internal combustion engines have been widely used in automobiles and power generators. However, to realize a sustainable society, it is necessary to improve thermal efficiency by improving existing internal combustion engines. As one of the methods to improve thermal efficiency, we are studying a multi-stage impinging injection method. In this study, we investigated the effects of premixing and fuel atomization by changing the fuel injection ratio on the combustion characteristics from the viewpoints of heat release ratio, Ignition delay time(ID), Total heat release(THR), total burning time(TBT), and Maximum burning pressure(MBP). The main conclusions are as follows:(1) It is possible to control combustion by the ratio of premixed combustion using multi-stage impinging injection.(2) When the multi-stage impinging injection is used, the THR is increased by up to 8% even at the same overall equivalence ratio by controlling the injection amount and injection timing of different fuels.(3) When the multi-stage impinging injection is used, the MBP is increased by up to 9% and the TBT is reduced by up to 10% by controlling the injection amount and injection timing of different fuels
EXPERIMENTAL STUDY ON INTERIOR PROPAGATION OF NOISE AND VIBRATION CAUSED BY EXTERNAL FLOW AROUND HIGH-SPEED VEHICLE
Get PDFAmong the aerodynamic noises generated by railway vehicles running at high speed, the noise generated by the structure on the roof not only affects the environment along the railroad tracks outside the vehicle, but also propagates inside the vehicle, damaging the comfort of the cabin. Interior noise is a combination of flow-induced aerodynamic noise propagating acoustically and structural excitation caused by pressure fluctuation due to wake vortices around the structure, and these two phenomena have not been investigated quantitatively.In this study, the effects of aerodynamic noise generated by structures in the airflow on the acoustic environment inside the vehicle are experimentally investigated using a small low noise wind tunnel from the viewpoint of source and propagation characteristics, and practical modeling of those effects is attempted
SYNTHESIS OF SILICON-CONTAINING LADDER-TYPE OLIGOMERS AND EXTENSION OF CONJUGATED SYSTEMS
Get PDFIn this study, ladder type tetramer 7 was prepared at -78 °C by Br-Li exchange reaction of precursor 1 having a fluorine atoms on the silicon atoms with tert-buthyl lithium. Reaction of 7 with MeLi gave methylated tetramer 11. The reaction of dimers 4 and 8 with silyllithiums did not produce silylated products 14. Reaction of dimer 4 with lithium acetylide produced 18. TD-DFT calculations revealed that conjugation of tetramer 11 and acetylides 18 were extended compared to dimer 9
Hardware Implementation of Classical Conditioning of Rescorla-Wagner Model with Timing Drift-Diffusion Model
Get PDFA novel hardware-efficient neuronal network having conditioning functions is proposed, where its nonlinear dynamics is designed based on ergodic cellular automaton. The proposed network is implemented by an FPGA and experiments validate its conditioning functions. It is shown that the network can be implemented by fewer circuit elements and consumes lower power than a conventional conditioning model
CHARACTERIZATION OF ELECTROCHEMILUMINESCENT DEVICES WITH METAL OXIDE NANOPARTICLE LAYERS
Get PDFWe proposed simple structured electrogenerated chemiluminescence (ECL) devices having titanium dioxide nanoparticles (TiO_2 NPs) as an electron injection layer (EIL). The EIL paste was formed on a cathode substrate and annealed at three different temperatures of 250 °C, 350 °C, and 450 °C for 30 min. A tris(2,2\u27-bipyridine) ruthenium (II) solution was used as an emitter. By applying DC voltage to the devices, orange-red ECL emission was obtained. The maximum luminance and half-lifetime of the 450 °C-annealed cell were 91.9 cd/m^2 and 16 s, respectively. The ECL performances were significantly increased with the increase in the annealing temperature. The results of surface analysis by SEM-EDS suggested that residual organic substances on the EIL surface were drastically reduced. From these results, the carrier balance was improved by the efficient generation of reduced species
A Novel Ergodic Discrete Difference Equation Cochlear Model
Get PDFIn this paper, a novel hardware-efficient electronic circuit cochlear model, the dynamics of which are described by an ergodic cellular automaton, is presented. Based on theoretical and numerical analyses, a parameter setting method so that the presented model properly works as a cochlear model is proposed. It is shown that the presented cochlear model designed by the proposed parameter setting method can reproduce typical nonlinear sound processing functions of mammalian cochleae such as nonlinear compression, two-tone suppression and two-tone distortion products. Furthermore, the presented model is implemented by a field programmable gate array (FPGA) and its operations are validated by experiments. It is shown that the presented model is much more hardware-efficient (i.e., consumes many fewer circuits elements) compared to some other electronic circuit cochlear models
Research on WPT-Robot : Comparison and Study of Wireless Power Transfer Methods for Tracking and Charging Function
Get PDFAs factories become increasingly unmanned, the operation rate of autonomous mobile transport vehicles (AGVs, AMRs, etc.) is increasing. In recent years, automatic power transfer using wireless power transfer has been proposed as a power transfer method to reduce maintenance costs and labor costs. However, AGVs must stop when transferring power, which results in non-working time.Therefore, we aim to reduce non-work time by using an autonomous mobile robot (WPT-Robot in this paper) that wirelessly transfers power while following behind an AGV. In this paper, we propose two wireless power transfer control schemes for the system and compare and discuss them
STUDY ON NONLINEAR MAGNETIC FIELD ANALYSIS OF ELECTROMAGNETIC STEEL SHEETS CONSIDERING MAGNETIC ANISOTROPY
Get PDFTo reduce carbon dioxide emissions, it is important to conserve energy and promote the spread and expansion of renewable energy. Therefore, it is important to improve the efficiency of electromagnetic transformers. Transformers have been designed to reduce losses by using high-performance materials such as amorphous alloys and by optimizing the winging design, but little consideration has been given to reducing losses by optimizing the geometry of the iron core. First, a linear analysis is performed using the finite element method, taking magnetic anisotropy into account. Then, nonlinear analysis is performed using the newton-raphson method. Therefore, I propose a nonlinear analysis that takes magnetic anisotropy into account. Since two-dimensional magnetic characteristics are taken into account, more accurate analysis is possible, and the analysis is also useful for other electromagnetic devices. In this paper, I compare and discuss the calculation accuracy and speed
COUNTERMEASURES AGAINST NONLINEAR DISTORTION AND FLICKER NOISE GENERATED BY SWITCHES AND INTEGRATORS IN SAR-DSM 2-STEP ADC
Get PDFThis paper describes the factors that deteriorate the signal-to-noise ratio (SNR) and signal-to-noise and distortion ratio (SNDR) of the system at the transistor level and the countermeasures against them. First, a two-step ADC is an ADC that performs conversion in two steps: a first-stage course conversion and a second-stage fine conversion. An ADC using a 4-bit SAR ADC and a 5-level DSM, respectively, is called a SAR-DSM 2-STEP ADC. In previous studies, thermal noise, flicker noise, and switch nonlinearity have not been sufficiently investigated. In this study, SNR was improved by 4.3 dB with flicker noise and by 12.5 dB without flicker noise
RESEARCH ON DISTRIBUTED STORAGE SCHEMES USING BLOCKCHAIN IN IOT DEVICES
Get PDFIn recent years, cloud storage has begun to be used by consumers. However, the major cloud storage services currently available have the potentials to be hacked by a comapany’s servers, or even by an insider to steal or extract the data they have been asked to store. There are systems that use blockchain to solve this problem, but they require the use of high-performance terminals such as PCs, since blockchain nodes need to be set up. In this study, we propose a method that allows a small terminal to communicate with distributed storage via a PC at home