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Authentication Method Using a Discrete Wavelet Transform for a Digital Moving Image

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Journal of Information Security 2016年第1期7卷 1-13页

作者： Ren Fujii yasunari yoshitomi Taro Asada Masayoshi Tabuse Graduate School of Life and Environmental Sciences Kyoto Prefectural University Kyoto Japan

Recently, several digital watermarking techniques have been proposed for hiding data in the frequency domain of moving image files to protect their copyrights. However, in order to detect the water marking sufficiently after heavy compression, it is necessary to insert the watermarking with strong intensity into a moving image, and this results in visible deterioration of the moving image. We previously proposed an authentication method using a discrete wavelet transform for a digital static image file. In contrast to digital watermarking, no additional information is inserted into the original static image in the previously proposed method, and the image is authenticated by features extracted by the wavelet transform and characteristic coding. In the present study, we developed an authentication method for a moving image by using the previously proposed method for astatic image and a newly proposed method for selecting several frames in the moving image. No additional information is inserted into the original moving image by the newly proposed method or into the original static image by the previously proposed method. The experimental results show that the proposed method has a high tolerance of authentication to both compressions and vicious attacks.

关键词： Authentication Moving Image Copyright Protection Tolerance to Compression Wavelet Transforms

An Authentication Method for Digital Audio Using a Discrete Wavelet Transform

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Journal of Information Security 2011年第2期2卷 59-68页

作者： yasunari yoshitomi Taro Asada Yohei Kinugawa Masayoshi Tabuse Graduate School of Life and Environmental Sciences Kyoto Prefectural University

Recently, several digital watermarking techniques have been proposed for hiding data in the frequency domain of audio files in order to protect their copyrights. In general, there is a tradeoff between the quality of watermarked audio and the tolerance of watermarks to signal processing methods, such as compression. In previous research, we simultaneously improved the performance of both by developing a multipurpose optimization problem for deciding the positions of watermarks in the frequency domain of audio data and obtaining a near-optimum solution to the problem. This solution was obtained using a wavelet transform and a genetic algorithm. However, obtaining the near-optimum solution was very time consuming. To overcome this issue essentially, we have developed an authentication method for digital audio using a discrete wavelet transform. In contrast to digital watermarking, no additional information is inserted into the original audio by the proposed method, and the audio is authenticated using features extracted by the wavelet transform and characteristic coding in the proposed method. Accordingly, one can always use copyright-protected original audio. The experimental results show that the method has high tolerance of authentication to all types of MP3, AAC, and WMA compression. In addition, the processing time of the method is acceptable for every-day use.

关键词： Authentication Audio Copyright Protection Tolerance to Compression Wavelet Transforms

Audio Watermarking Using Wavelet Transform and Genetic Algorithm for Realizing High Tolerance to MP3 Compression

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Emergence of immunotherapy as a novel way to treat hepatocellular carcinoma

Journal of Information Security（信息安全） 2011年第3期

作者： Shinichi Murata yasunari yoshitomi Hiroaki Ishii

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World Journal of Gastroenterology 2018年第17期24卷 1839-1858页

作者： Naofumi Mukaida yasunari Nakamoto Division of Molecular Bioregulation Cancer Research Institute Kanazawa University Second Department of Internal Medicine Faculty of Medical Sciences University of Fukui

Tumor immunity proceeds through multiple processes, which consist of antigen presentation by antigen presenting cells(APCs) to educate effector cells and destruction by the effector cytotoxic cells. However, tumor immunity is frequently repressed at tumor sites. Malignantly transformed cells rarely survive the attack by the immune system, but cells that do survive change their phenotypes to reduce their immunogenicity. The resultant cells evade the attack by the immune system and form clinically discernible tumors. Tumor microenvironments simultaneously contain a wide variety of immune suppressive molecules and cells to dampen tumor immunity. Moreover, the liver microenvironment exhibits immune tolerance to reduce aberrant immune responses to massively-exposed antigens via the portal vein, and immune dysfunction is frequently associated with liver cirrhosis, which is widespread in hepatocellular carcinoma(HCC) patients. Immune therapy aims to reduce tumor burden, but it is also expected to prevent non-cancerous liver lesions from progressing to HCC, because HCC develops or recurs from noncancerous liver lesions with chronic inflammatory states and/or cirrhosis and these lesions cannot be cured and/or eradicated by local and/or systemic therapies. Nevertheless, cancer immune therapy should augment specific tumor immunity by using two distinct measures: enhancing the effector cell functions such as antigen presentation capacity of APCs and tumor cell killing capacity of cytotoxic cells, and reactivating the immune system in immune-suppressive tumor microenvironments. Here, we will summarize the current status and discuss the future perspective on immune therapy for HCC.

关键词： natural killer T cell natural killer cell chimeric antigen receptor T cell T cell receptor cytokine-induced killer cell program death-1 cytotoxic lymphocyte antigen-4 regulatory T cell dendritic cell myeloid-derived suppressor cell PD-ligand 1 peptide vaccine tumor-associated antigen tumor infiltrating lymphocyte

Comment on“Perihilar cholangiocarcinoma-novel benchmark values for surgical and oncological outcomes from 24 expert centers”

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Hepatobiliary Surgery and Nutrition 2022年第2期11卷 314-316页

作者： yasunari Kawabata Yoshitsugu Tajima Department of Digestive and General Surgery Shimane University Faculty of MedicineIzumoShimaneJapan

Perihilar cholangiocarcinoma(PHC)is an aggressive malignancy of the biliary tracts with a dismal *** the primary goal of surgery for PHC is complete tumor removal with negative resection margins and regional lymphadenectomy,surgery for PHC with curative intent remains a challenge for surgeons because it involves complex surgical procedures such as bile duct resection,major hepatectomy,and/or vascular *** intensive procedures are often associated with postoperative complications,including severe morbidity and 30-day mortality with incidences of 40%and 5%,respectively(1).From the perspective of surgical and oncological safety,the standardization of aggressive surgical approaches and the establishment of standardized benchmark values that secure the best achievable outcomes are warranted in the treatment of patients with PHC.

关键词： surgical surgery mortality

Analysis of Aerodynamic Load on Straight-bladed Vertical Axis Wind Turbine

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Journal of Thermal Science 2014年第4期23卷 315-324页

作者： Qing’an LI Takao MAEDA yasunari KAMADA Junsuke MURATA Toshiaki KAWABATA Kazuma FURUKAWA Division of System Engineering Mie University1577 Kurimamachiya-choTsuMie 514-8507JAPAN Division of Mechanical Engineering Mie University1577 Kurimamachiya-choTsuMie 514-8507JAPAN

This paper presents a wind tunnel experiment for the evaluation of energy performance and aerodynamic forces acting on a small straight-bladed vertical axis wind turbine(VAWT) depending on several values of tip speed ratio. In the present study, the wind turbine is a four-bladed VAWT. The test airfoil of blade is symmetry airfoil(NACA0021) with 32 pressure ports used for the pressure measurements on blade surface. Based on the pressure distributions which are acted on the surface of rotor blade measured during rotation by multiport pressure-scanner mounted on a hub, the power, tangential force, lift and drag coefficients which are obtained by pressure distribution are discussed as a function of azimuthally position. And then, the loads which are applied to the entire wind turbine are compared with the experiment data of pressure distribution. As a result, it is clarified that aerodynamic forces take maximum value when the blade is moving to upstream side, and become small and smooth at downstream side. The power and torque coefficients which are based on the pressure distribution are larger than that by torque meter.

关键词： Wind Turbine Wind Energy Straight-bladed VAWT Tip Speed Ratio Pressure Distribution

Study on Blade Surface Flow around Wind Turbine by Using LDV Measurements

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Journal of Thermal Science 2015年第2期24卷 131-139页

作者： Tinnapob Phengpom yasunari Kamada Takao Maeda Junsuke Murata Shogo Nishimura Tasuku Matsuno Division of System Engineering Mie University Division of Mechanical Engineering Mie University

This paper has attempted to study a mechanism of three-dimensional flow around a horizontal axis wind turbine(HAWT) rotor blade. An experimental study of the flow phenomenon in the vicinity of the wind turbine blade is a challenging endeavor. In this research, the HAWT model with 2.4 m diameter was tested in the large wind tunnel. The flow around the rotating blade surface was measured simultaneously for three velocity components, and two probes were used for the synchronized measurement of three-dimensional flow components. The local velocity was detected for the single seeding particle measured in the point where three pairs of laser beams intersected. Blade sections of interest in this study are composed of radial positions r/R = 0.3, 0.5 and 0.7. Optimum and low tip speed ratio flow characteristics were also compared. The velocity flow vector, skin friction coefficient and bound circulation were calculated from LDV measurements, and the experimental research showed reasonably and clearly the experimental results.

关键词： LDV measurement Sectional performance Wind turbine Boundary layer flow Span-wise flow

A Straight-bladed Vertical Axis Wind Turbine with a Directed Guide Vane Row-Effect of Guide Vane Geometry on the Performance-

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Journal of Thermal Science 2009年第1期18卷 54-57页

作者： Manabu TAKAO Hideki KUMA Takao MAEDA yasunari KAMADA Michiaki OKI Atsushi MINODA Department of Mechanical Engineering Matsue National College of Technology Department of Mechanical Engineering Mie University

The objective of this study is to show the effect of guide vane geometry on the performance. In order to overcome the disadvantages of vertical axis wind turbine, a straight-bladed vertical axis wind turbine （S-VAWT） with a directed guide vane row has been proposed and tested by the authors. According to previous studies, it was clarified that the performance of the turbine can be improved by means of the directed guide vane row. However, the guide vane geometry of S-VAWT has not been optimized so far. In order to clarify the effect of guide vanegeometry, the effects of setting angle and gap between rotor blade and guide vane on power coefticlent and start- ing characteristic were investigated in the experiments. The experimental study of the proposed wind turbine was carried out by a wind tunnel. The wind tunnel with a diameter of 1.8m is open jet type. The wind velocity is 8 m/s in the experiments. The rotor has three straight blades with a profile of NACA0018 and a chord length of 100 mm, a diameter of 0.6 m and a blade height of 0.7 m. The guide vane row consists of 3 arc plates.

关键词： fluid machinery wind energy vertical axis wind turbine guide vane

Wind Tunnel Study on Wind and Turbulence Intensity Profiles in Wind Turbine Wake

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Journal of Thermal Science 2011年第2期20卷 127-132页

作者： Takao MAEDA yasunari KAMADA Junsuke MURATA Sayaka YONEKURA Takafumi ITO Atsushi OKAWA Tetsuya KOGAKI Division of Mechanical Engineering Mie University National Institute of Advanced Industrial Science and Technology

In recent years, there has been a rapid development of the wind farms in Japan. It becomes very important to investigate the wind turbine arrangement in wind farm, in order that the wake of one wind turbine does not to interfere with the flow in other wind turbines. In such a case, in order to achieve the highest possible efficiency from the wind, and to install as many as possible wind turbines within a limited area, it becomes a necessity to study the mutual interference of the wake developed by wind turbines. However, there is no report related to the effect of the turbulence intensity of the external flow on the wake behind a wind turbine generated in the wind tunnel. In this paper, the measurement results of the averaged wind profile and turbulence intensity profile in the wake in the wind tunnel are shown when the turbulence intensity of the external wind was changed. The wind tunnel experiment is performed with 500mm-diameter two-bladed horizontal axis wind turbine and the wind velocity in wake is measured by an I-type hot wire probe. As a result, it is clarified that high turbulence intensities enable to the entrainment of the main flow and the wake and to recover quickly the velocity in the wake.

关键词： Horizontal axis wind turbine Wake Wind profile Turbulence intensity Power output