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STUDY ON ELECTRIFICATION OF LIGHT HELICOPTER
Get PDFIn recent years, Reduction of the environmental load has been advocated in all industries, decarbonization is progressing as a global trend, and the aviation industry is no exception. While the electrification of aircraft has been actively researched as well as the idea of using electric aircraft has raised in the concept of UAM (Urban Air Mobility), which was devised as a new means of urban transportation. However, there are major obstacles to the development of new aircraft, and it is possible to apply to existing aircraft and bring them to market faster. It is expected that electric helicopters capable of vertical takeoff and landing will be able to meet the demand, but there are little trial cases. In this research, characteristics of a new electric light helicopter through conceptual design were discussed and compared the performance and usability with the existing aircraft
A STUDY FOR EFFECTS OF BUTANOL ADDITION ON COMBUSTION PRODUCTS FOR SMALL GASOLINE ENGINE BY USING STANDARD FUEL WITH ISO-OCTANE AND TOLUENE
Get PDFIt is known that the component proportion of gasoline varies depending on the mining time of crude oil, the mining place, and so on. Because it has effects on the engine performance and emission characteristics, studying about the effects of the fuel properties on combustion characteristics is important. And a study for power generation small gasoline engine by using alcohol fuels as gasoline alternative fuels has been carried out. These points, this experiment has been conducted to examine about the reduction of combustion products for power generation small gasoline engine by using standard fuel with Iso-Octane and Toluene in wide open throttle and throttle opening 2/3, especially about the effects of fuel properties by changing addition ratio of 1-Butanol, 2-Butanol, Isobutanol, and t-Butanol with volume ratio of 54vol.%～68vol.%. The main conclusions are as follows: 1) 1-Butanol, 2-Butanol, Isobutanol, and t-Butanol are suitable for addition fuels, and it is possible to reduce CO and HC emissions remarkably with high addition ratio of 54vol.%～68vol.% for small gasoline engine by using standard fuel with Iso-Octane and Toluene. 2) The CO reduction of about 41.3% or more and the HC reduction of about 26.0% or more compared with 2-Butanol, Isobutanol, and t-Butanol can accomplish when changing addition ratio of 1-Butanol with volume ratio of 54vol.%～68vol.% and setting the no load condition or the load condition as the neighborhood of low and medium range for small gasoline engine by using standard fuel with Iso-Octane and Toluene
A STUDY OF THE EFFECTS FOR ALCOHOL AQUEOUS FUEL ADDITION AND DISPLACEMENT ON THE COMBUSTION PRODUCTS OF A SAMLL GASOLINE ENGINE FOR ELECTRIC POWER GENERATOR
Get PDFNowadays, the small generators are widely used as a primary power supply to protect family health care and infrastructure while the cut-off happens at extreme weather or disasters. However, the stabilizing fuel supply is a problem under that situation. It is urgency to looking for renewable substitute fuel. From these viewpoints, this study focused on the exhaust characteristics of small power generation engines with alternative fuel as alcohol fuel and investigated the influence of water addition ratio in ethanol aqueous on engine performance and emission characteristics
DIRECT SYNTHESIS OF MESOPOROUS SILICA USING SILICA IN GEOTHERMAL WATER AND THE EVALUATION OF FUNDAMENTAL PERFORMANCE
Get PDFMesoporous silica was synthesized using the geothermal water from the Onuma geothermal power plant in Akita Prefecture, Japan. Cetyltrimethylammonium bromide (CTAB) was reacted with geothermal water at a temperature of 90℃, with a total silicic acid concentration of 475 ppm (SiO_2) at pH 7, pH 8, pH 9, and pH 10 for 30 min. The total silicic acid concentration in the solution after formation of mesoporous silica at pH 9 was reduced to under 300 ppm. By calcining of the product at 550℃, mesoporous silica with pore sizes of about 2.8 nm and a specific surface area of 919 m^2/g was formed. The monosilicic acid in geothermal water plays an important role in the formation of mesoporous silica
PROPOSAL AND EVALUATION OF A HYBRID SEARCH PATH GENERATION METHOD COMBINING INSECT FORAGING ALGORITHM AND GRID SEARCH
Get PDFThe application of robots or drones to search for survivors in disaster sites has recently attracted considerable attention. In our previous studies, we focus on the behavior of insects and propose a simple and efficient path generation algorithm for search and rescue robots. In addition, we optimized parameters using a genetic algorithm. In this study, we analyze the generated paths, and propose the optimal search path using the analyzed data
An approach toward pareto front based dimensionality reduction of parameters in nonlinear circuits
Get PDFIn this thesis, we consider dimensionality reduction of parameters in a piecewise linear model of boost converter with PV input. The circuit is subject to a bi-objective optimization problem where the first and second objectives evaluate efficiency of input power and stability of periodic orbits, respectively. A trade off exists between the two objectives and is represented by a Pareto front. An approximation of the Pareto front is a criterion for the dimensionality reduction. Performing precise numerical experiment, a simple dimensionality reduction from two-dimensional parameter space into a one-dimensional parameter subspace is achieved
DEVELOPMENT OF A DUPLEX CYLINDRICAL FLEXIBLE ROBOT : NEJIRI : REALIZATION OF TURNING AND TRANSLATIONAL MOTION BY USING TWISTING MOTION
Get PDFIn this study, we propose a novel twisting mechanism for a cylindrical soft robot to move. The proposed mechanism has a duplex structure comprising a silicone rubber hose and a flexible shaft. Each side of the robot has a geared motor, and the robot shortens and lengthens by rotating each motor. When rotating one motor, the shape of the robot generates a spiral wave, and its length shortens. Then, by rotating the other motor to loosen the spiral, the shape of the robot returns to a natural shape, and the center of gravity moves as well. By simply repeating these motions, locomotive behavior is realized, and the robot moves toward the desired direction. To demonstrate the effectiveness of the proposed mechanism, we developed a prototype. Moreover, to confirm its mobility, experiments were conducted. According to the results, we confirmed that the desired turning and translational motion were realized, and the robot was able to move toward the desired direction on a flat horizontal plane and through a pipe
Sentiment Analysis Using an CNN-BiLSTM Deep Model Based on Attention Classification
Get PDFSentiment analysis has been a hot research topic in NLP and data mining fields in the last decade. To solve the feature dimension is too high and the pool layer information is lost, which leads to the loss of the details of the emotion vocabulary. I proposed a Word2vec-CNN-BiLSTM hybrid model means the Word Vector Model, Bidirectional Long-term and Short-term Memory networks and convolutional neural network are combined in Quora dataset. The experiment shows that the accuracy achieved 91.48% performs better than each single model in short text. However, even with the hybrid approach that leverages the powers of these two deep-learning models, the number of features remains huge and hindering the training process. Secondly, I propose an attention-based CNN-BiLSTM hybrid model in IMDB movie reviews dataset. When the data size was 13 k, the proposed model had the highest accuracy at 0.908, and the F1 score also showed the highest performance at 0.883. When data was 20 k, the F1 score showed the best performance at 0.906, and accuracy was the highest at 0.929. The experimental results show that the BiLSTM-CNN model based on attention mechanism can effectively improve the performance of sentiment classification when processing long-text tasks
SpeedDeblur : A Framework to speed up CNN-based Deblurring for HEVC compressed video
Get PDFThis paper proposes a speedup convolutional neural network (CNN)-based deblurring framework (SpeedDeblur) for reconstructed blurry videos. First, we extract the coding information and the reconstructed video from the compressed data. Second, a CNN-based algorithm is used for deblurring the first reconstructed frame. Pixels of the deblurred frames are transferred to the subsequent frames guided by HEVC decoded data. The transferring process is simple and faster than applying a deblurring algorithm on all frames. However, passing pixels throughout a long video propagates accumulated errors and reduces the deblurring performance. To bridge this gap, we design an adaptive reset strategy for deciding which frame needs CNN-based deblur during the transfering process. Besides, a data generation strategy simulating blurry real-world factors such as camera shake and fast movement is proposed. Compared to frame-by-frame deblurring approaches, our framework can retain the same comparable results and boost the deblurring processing by up to 4.0× and 99.4× on GPU and CPU, respectively
A STUDY ON DYNAMIC SIGNAL ANALYSIS OF INTRA-BODY COMMUNICATION IN WALKING PERSONS
Get PDFThis paper describes a signal measurement for three walking persons in intra-body communication by using a dynamic signal measurement system. The power margin is proposed in a situation of three walking persons for preventing the system from wrong authentication caused by unintentional signal