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Journal of Materials Science and Chemical Engineering 2017年第12期5卷 52-62页

作者： ken-ichi hirota Masahiko Maeda College of Engineering Kanazawa Institute of Technology Ishikawa Japan

In order to clarify the visible-light responsive photocatalysis of TiO2 co-doped with Cu and N atoms, plasma-nitridation was taken place to Cu-doped TiO2 film. Cu-doped TiO2 films were prepared by dip-coating method and they were nitrided by nitrogen plasma in the plasma-enhanced CVD system. Cu-doped TiO2 films before and after plasma-nitridation show similar X-ray diffraction peaks of anatase TiO2. XPS analysis reveals that the ionic states of Ti and Cu in the Cu-doped TiO2 films are Ti4+ and Cu+, respectively. After nitrogen plasma treatment, oxygen atoms are released by substitution of nitrogen atoms in the TiO2 matrix, so that Cu+ is oxidized to generate Cu2+ and at the same time oxygen vacancy is formed. The absorption edge of both Cu-doped and plasma-nitrided Cu-doped TiO2 did red shift. Visible-light responsive photocatalytic activity of the Cu-doped TiO2 film degraded after nitrogen plasma treatment.

关键词： Sol-Gel Cu-Doped Titania Plasma-Nitridation Photocatalysis

A LESO Based Backstepping Controller Considering Coal Seam Hardness for Rotary Speed in Coal Mine Tunnel Drilling Process

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Journal of Systems Science & Complexity 2024年第5期37卷 1789-1808页

作者： CHEN Luefeng LIU Xiao WU Min LU Chengda PEDRYCZ Witold hirota Kaoru School of Automation China University of GeosciencesWuhan 430074China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan 430074China Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of EducationWuhan 430074China Department of Electrical and Computer Engineering University of AlbertaEdmontonAB T6R2G7Canada The Tokyo Institute of Technology Yokohama 226-8502Japan

In the process of coal mine drilling,controlling the rotary speed is important as it determines the efficiency and safety of *** this paper,a linear extended state observer(LESO)based backstepping controller for rotary speed is proposed,which can overcome the impact of changes in coal seam hardness on rotary ***,the influence of coal seam hardness on the drilling rig’s rotary system is considered for the first time,which is reflected in the numerical variation of load torque,and a dynamic model for the design of rotary speed controller is *** an LESO is designed to observe the load torque,and feedforward compensation is carried out to overcome the influence of coal seam *** on the model of the compensated system,a backstepping method is used to design a controller to achieve tracking control of the rotary ***,the effectiveness of the controller designed in this paper is demonstrated through simulation and field experiments,the steady-state error of the rotary speed in field is 1 r/min,and the overshoot is reduced to 5.8%.This greatly improves the stability and security,which is exactly what the drilling process requires.

关键词： Backstepping extended state observer hydraulic tunnel drilling machine rotary speed

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面向动态场景去模糊的对偶学习生成对抗网络

控制与决策 2024年第4期39卷 1305-1314页

作者：纪野戴亚平廣田薰邵帅北京理工大学自动化学院北京100081 北京理工大学复杂系统智能控制与决策国家重点实验室北京100081

针对动态场景下的图像去模糊问题,提出一种对偶学习生成对抗网络(dual learning generative adversarial network,DLGAN),该网络可以在对偶学习的训练模式下使用非成对的模糊图像和清晰图像进行图像去模糊计算,不再要求训练图像集合必... 详细信息

针对动态场景下的图像去模糊问题,提出一种对偶学习生成对抗网络(dual learning generative adversarial network,DLGAN),该网络可以在对偶学习的训练模式下使用非成对的模糊图像和清晰图像进行图像去模糊计算,不再要求训练图像集合必须由模糊图像与其对应的清晰图像成对组合而成.DLGAN利用去模糊任务与重模糊任务之间的对偶性建立反馈信号,并使用这个信号约束去模糊任务和重模糊任务从两个不同的方向互相学习和更新,直到收敛.实验结果表明,在结构相似度和可视化评估方面,DLGAN与9种使用成对数据集训练的图像去模糊方法相比具有更好的性能.

关键词：动态场景去模糊对偶学习生成对抗网络注意力引导特征图损耗函数

一种用于“远程课堂”的学生听课专注度自动评估方法

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北京理工大学学报 2024年第5期44卷 530-537页

作者：邵帅李思敏广田薰戴亚平北京理工大学自动化学院北京100081 中国电子科技集团公司第五十研究所上海200331 北京理工大学唐山研究所河北唐山063611

在基于互联网的“远程课堂”中,如何利用学生课堂状态视频数据建立教师与学生授课−听课之间的评价关联关系,是一项富有挑战性的科学问题.本文针对“远程课堂”中的学生行为检测识别问题,提出针对课堂学生“面部姿态角度”检测模块与“... 详细信息

在基于互联网的“远程课堂”中,如何利用学生课堂状态视频数据建立教师与学生授课−听课之间的评价关联关系,是一项富有挑战性的科学问题.本文针对“远程课堂”中的学生行为检测识别问题,提出针对课堂学生“面部姿态角度”检测模块与“身体动作行为”识别模块,对学生的课堂行为进行识别分类;针对“学生听课专注度”的定量分析问题,提出一种基于学生面部姿态角度和行为分类结果的量化评估算法;运用证据理论对“面部姿态”与“动作行为”并行进行数据融合计算,建立用于“远程课堂”的在线“学生听课专注度”自动评估系统模型.本文所提模型能够对课堂学生的听课行为进行在线检测与分析,完成“学生听课专注度”的定量评分并输出评估结果.实验中,系统对“学生听课专注度”的评估准确度达到90.4%,验证了系统的有效性.

关键词：深度学习图像分析行为识别数据融合远程课堂专注度评估

Local records of long-term dynamics of bamboo gregarious flowering in northern Laos and regional synchronicity of Dendrocalamus membranaceus in two flowering sites

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Journal of Mountain Science 2017年第6期14卷 1058-1064页

作者： hirota Isao Gifu University - Faculty of Applied Biological Sciences Yanagido 1-2 Gifu 501-1193 JAPAN Gifu 501-1193 Japan

Bamboos are widely distributed in mainland Southeast Asia and have abundant biomass. They are characterized by prolonged vegetative growth and semelparity. Where bamboos are dominant, their synchronous flowering and death has a major impact on forest vegetation. Although the small-scale dynamics of this process have become clearer in recent years, the history, geographical scale and synchronicity of bamboo flowering over broad areas remains unknown. This study focused on the flowering history of six bamboo species, Bambusa tulda, Cephalostachyum virgatum, Dendrocalamus hamiltonii, Dendrocalamus membranaceus, Indosasa sinica and Oxytenanthera parvifolia, over 40 years across a broad area of northern Laos. We also examined the synchronicity of flowering in D. membranaceus. We visited 49 villages in northern Laos and surveyed knowledgeable inhabitants about bamboo flowering history. The timing, scale and synchronicity of gregarious flowering varied among species. D. hamiltonii and D. membranaceus showed higher flowering synchronicity than other species. All the species except I. sinica had both sporadic and gregarious flowering traits, and showed conspicuous variability in their flowering scale. The flowering bamboo population at two gregarious flowering sites for D. membranaceus was surveyed. While thisspecies had the highest synchronicity in this study, its synchronicity was lower than other species in previous studies worldwide. We found that the gregarious flowering of bamboos in northern Laos over the last 40 years showed lower synchronicity than bamboo flowering reported in other areas of the world. The historical dynamics and scale of bamboo flowering must be further clarified to understand the vegetation composition of this area.

关键词： Fallow forest Sporadic flowering Shifting cultivation Synchronicity Southeast Asia

Energetics of Resistive Wall Modes in Flowing Plasmas

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Plasma Science and Technology 2009年第4期11卷 409-412页

作者： M.hirota Japan Atomic Energy Agency

Stabilization/destabilization of magnetohydrodynamic （MHD） waves are formulated in terms of wave energy, where the waves are subject to Alfven and sound resonances and also influenced by small resistivity at conductive wall. Negative energy wave, which may exist in the presence of mean flow, is shown to be destabilized by the resistive wall, where its growth rate is characterized by the energy dissipation rate. The effect of resonance is examined as well based on a recent knowledge of wave energy for Alfv4n and sound continuum modes. Resonant coupling between an eigenmode and a continuum mode having the same sign of energy results in phase mixing （or continuum） damping. In contrast, if their signs are opposite, such resonance triggers an instability.

关键词： MHD stability resitive wall mode flowing plasma wave energy

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教室环境下的教学质量AI机器评估研究进展

北京理工大学学报 2024年第10期44卷 1077-1088页

作者：广田薰周政 MERSHA Bemnet Wondimagegnehu 戴亚平北京理工大学自动化学院北京100081 北京理工大学唐山研究院河北唐山063611

借助于人工智能(artificial intelligent,AI)技术,实现教室环境下课堂教学质量的机器自动评估,是一项富有挑战性的工作.针对教学质量AI机器评估问题,介绍传统的教学质量评估方法,分析机器评估使用的相关AI技术;并以不同的评估技术为主线... 详细信息

借助于人工智能(artificial intelligent,AI)技术,实现教室环境下课堂教学质量的机器自动评估,是一项富有挑战性的工作.针对教学质量AI机器评估问题,介绍传统的教学质量评估方法,分析机器评估使用的相关AI技术;并以不同的评估技术为主线,对教室环境下的AI机器评估研究进展进行详细归纳与分析,指出目前机器评估面临的挑战.

关键词：人工智能课堂教学质量评估机器评估深度学习

Livelihood Factors and Household Strategies for an Unexpected Climate Event in Upland Northern Laos

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Journal of Mountain Science 2015年第2期12卷 483-500页

作者： Phanxay INGXAY Satoshi YOKOYAMA Isao hirota Department of Geography Graduate School of Environmental Studies Nagoya University Graduate School of Bioagricultural Sciences Nagoya University

Climate events pose major challenges to food production and the livelihoods of rural inhabitants in northern Laos, where upland rice using swidden production is an important crop. The onset of the rainy season in this area is one such climate event, and it has occurred earlier and with less regularity in recent years. Not all households are able to cope with these changes. This study examines the ability of local farmers to cope with rice insufficiency. This investigation also clarifies household strategies in dealing with the climate event. We randomly interviewed 63 of 95 household heads, and performed a paired sample t test to examine the significance of differences in three household groups between the 2010 normal climate and the 2011 climate event. The groups were categorized according to rice selfsufficiency in 2011: groups I are households with rice self-sufficiency, group II are those facing a rice shortage of up to 3 months, and group III are those with insufficient rice for over 3 months. We also conducted a one-way ANOVA to examine the significance of differences in livelihood strategies among the three groups. We found that the household labor force was the most important factor in enhancing the villagers' ability to deal with the climate event and that the level of impact of that event shaped their coping strategies. Households with substantial labor force had more options for coping strategies than those with smaller ones. The villagers faced different levels of impact and adopted differentcoping strategies accordingly. Non-timber forest product collection was the principle livelihood strategy in response to non-climate factors such as education, access to health services, provision of equipment and clothing, and overcoming the impact of the climate event. Households heavily affected by the early rainy season onset tended to engage in intensive activities such as off-farm activity and outside work, rather than their major livelihood activities in the v

关键词： Climate events Livelihood factors Livelihood change Household strategy Swidden

Fabrication of ZrC/ZrB₂/C Composites Having High Mechanical Properties at Elevated Temperatures

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Materials Sciences and Applications 2022年第4期13卷 232-248页

作者： Kai Matsumoto Masaki Kato ken hirota Toshiyuki Nishimura Department of Molecular Chemistry & Biochemistry Faculty of Science & Engineering Doshisha University Kyotanabe Japan National Institute for Materials Science Tsukuba Japan

Ultra-high temperature ceramics (UHTCs) are most recently getting much attention for structural parts of hypersonic missiles with their cruising speed of more than Mach 5. Most of the UHTCs are poor sinterability carbides, nitrides, and borides. Therefore, they have been studied and developed for a long time. However, there are still many problems to solve. In this paper, based on the solid-state reaction presented as an equation of (x + y)·ZrC + 2·y·B → x·ZrC + y·ZrB2 + y·C, three-phase ZrC/ZrB2/C composites have been fabricated from ZrC and amorphous B powders using pulsed electric-current pressure sintering at 1373 to 2173 K for 6.0 × 102 s under 50 MPa in a vacuum. ZrC/ZrB2/C = 30/70/C~70/30/C vol% composites with the relative densities Dr of 96.6 to 98.7% were obtained at 2073 K. The 60/40/C vol% composite revealed high bending strength σb (554 MPa), Vickers hardness Hv (19.2 GPa) and moderate fracture toughness KIC (5.25 MPa·m1/2) at room temperature. Furthermore, all composites showed elastic deformation up to 1873 K and revealed σb more than 600 MPa at this temperature, in addition, some composites showed higher σb than 900 MPa at the same temperature. These high mechanical behaviors are discussed with those of the simple binary ZrC/ZrB2 composites which were fabricated under the same conditions except for their starting materials. The best mechanical properties of binary composites were σb (474 MPa), Hv (18.5 GPa), and KIC (4.45 MPa·m1/2) at room temperature, and σb of 400 - 700 MPa at 1873 K. Overall, three-phase composites, nevertheless including soft carbon, have higher mechanical properties than the binary composites.

关键词： ZrC ZrB2 C Composites Pulsed Electric-Current Pressure Sintering Mechanical Properties

Immobilization of cross-linked In-doped Mo(O,S)2 on cellulose nanofiber for effective organic-compound degradation under visible light illumination

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Progress in Natural Science:Materials International 2021年第3期31卷 404-413页

作者： Hairus Abdullah Chi-Ning Hsu Hardy Shuwanto Noto Susanto Gultom Worku Lakew Kebede Chang-Mou Wu Chiu-Chun Lai Ri-ichi Murakami Masayuki hirota Antonio Norio Nakagaito Dong-Hau Kuo Department of Materials Science and Engineering National Taiwan University of Science and Technology Department of Textile Engineering Chinese Culture University New Material Research & Development Department Frontier Materials Laboratories Osaka Gas Chemicals Co. Ltd. Graduate School of Technology Industrial and Social Sciences Tokushima University

Relatively small amounts of In-doped Mo(O,S)2(IMS) catalysts(10%, 20%, and 30%) were deposited on cellulose nanofiber(CNF) by cross-linking them with functional groups of siloxane and epoxy to form CNF-IMS hybrid composites. The as-prepared hybrid composites were characterized and tested their performances toward the photo degradations of cationic(MB and Rh B) and anionic(MO) dyes. As indium was doped into Mo(O,S)2lattice to form solid-solution, the charge transfer and photocarrier separation during the catalytic reaction were simultaneously enhanced as probed with electrochemical impedance spectroscopy and photoluminescence measurements, respectively. To ensure the catalyst on CNF was well deposited and recyclable, the hybrid composite was evaluated with a reusability experiment to show the stability performance in degrading organic dyes. It was found the environmentally friendly CNF-IMS hybrid composite was relatively stable during the reusability experiment, indicating no catalyst powder was leached out during the photocatalytic reaction. The photoreaction mechanism was convinced by radical-scavenging experiments to show that hydroxyl and superoxide played essential roles for the organic dye degradations in visible-light illuminated conditions. The cross-linked organic/inorganic hybrid catalyst showed a prospective visible light active material not only to solve the environmental issue due to the leaching of nanoparticles but also to lower the post-treatment/recycling cost of photocatalyst in industrial application.

关键词： Cellulose nanofiber In-doped Mo(O,S) 2 Cross-linking In 2 (O,S) 3 Organic dye degradation