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Limb Stiffness Improvement of the Robot WAREC-1R for a Faster and Stable New Ladder Climbing Gait

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Journal of Bionic Engineering 2023年第1期20卷 57-68页

作者： Xiao Sun Akira ito Takashi Matsuzawa Atsuo Takanishi Department of Mechatronics University of YamanashiYamanashi400-8511Japan Faculty of Science and Engineering Waseda UniversityTokyo162-8480Japan

Ladder climbing is a relatively new but practical locomotion style for robots. Unfortunately, due to their size and weight, ladder climbing by human-sized robots developed so far is struggling with the speedup of ladder climbing motion itself. Therefore, in this paper, a new ladder climbing gait for the robot WAREC-1R is proposed by the authors, which is both faster than the former ones and stable. However, to realize such a gait, a point that has to be taken into consideration is the deformation caused by the self-weight of the robot. To deal with this issue, extra hardware (sensor) and software (position and force control) systems and extra time for sensing and calculation were required. For a complete solution without any complicated systems and time only for deformation compensation, limb stiffness improvement plan by the minimal design change of mechanical parts of the robot is also proposed by the authors, with a thorough study about deformation distribution in the robot. With redesigned parts, ladder climbing experiments by WAREC-1R proved that both the new ladder climbing gait and the limb stiffness improvement are successful, and the reduced deformation is very close to the estimated value as well.

关键词： Ladder climbing Legged robot Bionic robot Gait.Stiffness improvement Finite element analysis

Selective Mimics of Strigolactone Actions and Their Potential Use for Controlling Damage Caused by Root Parasitic Weeds

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Molecular Plant 2013年第1期6卷 88-99页

作者： Kosuke Fukui Shinsaku ito Tadao Asami Graduate School of Agricultural and Life Sciences University of Tokyo 1-1-1 Yayoi Bunkyo Tokyo Japan 113-8657 JST CREST 1-1-1 Yayoi Bunkyo Tokyo Japan 113-8657

Strigolactones （SLs） are a novel class of plant hormones and rhizosphere communication signals, although the molecular mechanisms underlying their activities have not yet been fully determined. Nor is their application in agriculture well developed. The importance of plant hormone agonists has been demonstrated in both basic and applied research, and chemicals that mimic strigolactone functions should greatly facilitate strigolactone research. Here, we report our discovery of a new phenoxyfuranone compound, 4-Br debranone （4BD）, that shows similar activity to that of the major strigolactone （SL） analog GR24 in many aspects of a biological assay on plants. 4BD strongly inhibited tiller bud outgrowth in the SL-deficient rice mutant d10 at the same concentration as GR24, with no adverse effects, even dur- ing prolonged cultivation. This result was also observed in the Arabidopsis thaliana SL-deficient mutants max1, max3, and max4. However, the application of 4BD to the Arabidopsis SL-insensitive mutant max2 induced no morphological changes in it. The expression of SL biosynthetic genes was also reduced by 4BD treatment, probably via negative feed- back regulation. However, in a seed germination assay on Striga hermonthica, a root parasitic plant, 4BD showed far less activity than GR24. These results suggest that 4BD is the first plant-specific strigolactone mimic.

关键词： strigolactones plant growth regulator Arabidopsis rice debranone branching tillering.

Multi-parameter Tikhonov Regularization—An Augmented Approach

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Chinese Annals of Mathematics,Series B 2014年第3期35卷 383-398页

作者： Kazufumi ito Bangti JIN Tomoya TAKEUCHI Center for Research in Scientific Computation & Department of Mathematics North Carolina State University Department of Mathematics University of California Riverside 900 University Ave.Riverside CA92521 USA. Collaborative Research Center for Innovative Mathematical Modelling Institute of Industrial ScienceThe University of Tokyo 4-6-1-Cw601 Komaba Meguro-ku Tokyo 153-8505 Japan.

We study multi-parameter regularization(multiple penalties) for solving linear inverse problems to promote simultaneously distinct features of the sought-for objects. We revisit a balancing principle for choosing regularization parameters from the viewpoint of augmented Tikhonov regularization, and derive a new parameter choice strategy called the balanced discrepancy principle. A priori and a posteriori error estimates are provided to theoretically justify the principles, and numerical algorithms for efficiently implementing the principles are also provided. Numerical results on deblurring are presented to illustrate the feasibility of the balanced discrepancy principle.

关键词： Multi-parameter regularization Augmented Tikhonov regularization Balanced discrepancy principle

Pink-color sign in esophageal squamous neoplasia, and speculation regarding the underlying mechanism

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World Journal of Gastroenterology 2013年第27期19卷 4300-4308页

作者： Ryu Ishihara Hiromitsu Kanzaki Hiroyasu Iishi Kengo Nagai Fumi Matsui Takeshi Yamashina Noriko Matsuura Takashi ito Mototsugu Fujii sachiko Yamamoto Noboru Hanaoka Yoji Takeuchi Koji Higashino Noriya Uedo Masaharu Tatsuta Yasuhiko Tomita Shingo Ishiguro Department of Gastrointestinal Oncology Osaka Medical Center for Cancer and Cardiovascular Diseases Department of Gastroenterology and Hepatology Okayama University Graduate School of Medicine Department of Pathology Osaka Medical Center for Cancer and Cardiovascular Diseases PCL Osaka Inc.

AIM:To investigate the reasons for the occurrence of the pink-color sign of iodine-unstained lesions. METHODS:In chromoendoscopy, the pink-color sign of iodine-unstained lesions is recognized as useful for the diagnosis of esophageal squamous cell carcinoma. Patients with superficial esophageal neoplasms treated by endoscopic resection were included in the study. Areas of mucosa with and without the pink-color sign were evaluated histologically. The following histologic features that were possibly associated with the pinkcolor sign were evaluated. The keratinous layer and basal cell layer were classified as present or absent. Cellular atypia was classified as high grade, moderate grade or low grade, based on nuclear irregularity, mitotic figures, loss of polarity, chromatin pattern and nuclear/cytoplasmic ratio. Vascular change was assessed based on dilatation, tortuosity, caliber change and variability in shape. Vessels with these four findings were classified as positive for vascular change. Endoscopic images of the lesions were captured immediately after iodine staining, 2-3 min after iodine staining and after complete fading of iodine staining. Quantitative analysis of color changes after iodine staining was also performed. RESULTS:A total of 61 superficial esophageal neoplasms in 54 patients were included in the study. The lesions were located in the cervical esophagus in one case, the upper thoracic esophagus in 10 cases, the mid-thoracic esophagus in 33 cases, and the lower thoracic esophagus in 17 cases. The median diameter of the lesions was 20 mm (range:2-74 mm). Of the 61 lesions, 28 were classified as pink-color sign positive and 33 as pink-color sign negative. The histologic diagnosis was high-grade intraepithelial neoplasia (HGIN) or cancer invading into the lamina propria in 26 of the 28 pink-color sign positive lesions. There was a significant association between pink-color sign positive epithelium and HGIN or invasive cancer (P = 0.0001). Univariate

关键词： Chromoendoscopy Esophageal cancer Esophageal squamous neoplasia Iodine staining Pinkcolor sign

Geochemistry of Triassic Siliceous Rocks of the Muyinhe Formation in the Changning-Menglian Belt of Southwest China

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Journal of Earth Science 2016年第3期27卷 403-411页

作者： Tsuyoshi ito Xin Qian Qinglai Feng State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Stratigraphy and Tectonics Research Group Institute of Geology and Geoinformation Geological Survey of Japan School of Earth Sciences China University of Geosciences

The Changning-Menglian belt, distributed over southwestern Yunnan Province in Southwest China, contains oceanic rocks that are considered to be remnants of the Paleotethys. This study observed Triassic siliceous rocks of the Muyinhe Formation in the Changning-Menglian belt and analyzed their geochemistry. The samples have high concentrations of SiO2（81.65 wt.%–88.38 wt.%; average： 84.99 wt.%±2.14 wt.%）. Most of the samples were plotted in the non-hydrothermal field on the Al-Fe-Mn diagram. Most of the samples were plotted in the continental margin field on the Fe2O3/TiO2-Al2O3/（Al2O3＋Fe2O3） and（La/Ce）N-Al2O3/（Al2O3＋Fe2O3） diagrams. Moreover, the samples show a flat REE（rare earth element） pattern normalized to NASC（North America shale composite）. These geochemical results, in addition to the lack of rhythmical bedding of the siliceous rocks, strongly suggest that the siliceous rocks are unlikely to represent pelagic deposits. Although previous studies have suggested that the siliceous rocks are pelagic deposits, the present results indicate that the extent of the pelagic ocean basins in the Paleotethys during the Triassic is probably less than previously believed. These non-pelagic deposits may represent the closure stage of the Paleotethys.

关键词： geochemistry Triassic siliceous rock Paleotethys Muyinhe Formation Changning-Menglian belt

Self-/conspecific discrimination and superparasitism strategy in the ovicidal parasitoid Echthrodelphax fairchildii （Hymenoptera： Dryinidae）

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Insect Science 2014年第6期21卷 741-749页

作者： Emi ito Yoshihiro Y. Yamada Insect Ecology Laboratory Graduate School of Bioresources Mie University Tsu Mie Japan

Superparasitism in solitary parasitoids results in fatal competition between the immature parasitoids, and consequently only one individual can emerge. In the semisoli- tary ovicidal parasitoid Echthrodelphaxfairchildii （Hymenoptera： Dryinidae）, 2 adults can emerge under superparasitism with a short interval （〈24 h） between the first and second ovipositions. We determined the female parasitoid＇s behavioral responses under self- and conspecific superparasitism bouts with first-to-second oviposition intervals of 〈2 h. The self- and conspecific superparasitizing frequencies increased up to an oviposition interval of 0.75 h, with the former remaining lower than the latter, particularly for oviposition intervals of _〈0.25 h, suggesting the existence of self-/conspecific discrimination. The superparasitizing frequency plateaued for oviposition intervals of _〉0.75 h, with no dif- ference between self- and conspecific superparasitism. The ovicidal-probing frequency did not differ under self- and conspecific superparasitism, and was usually 〈20%. The females exhibited no preference for the oviposition side （i.e., ovipositing on the side with or without the first progeny） and almost always laid female eggs for any oviposition in- terval under self- and conspecific superparasitism. The sex ratio was not affected by the type of superparasitism, oviposition sides, or the occurrence of ovicidal probing. These observed results about the oviposition side, ovicidal probing, and sex ratios differed from the predictions obtained assuming that the females behave optimally. Possible reasons for the discrepancies are discussed： likely candidates include the high cost of selecting oviposition sides and ovicidal probing, and, for the sex ratio, the low frequency of encountering suitable hosts before superparasitism bouts.

关键词： infanticide ovicide plant hopper self-recognition sex ratio

Uneven Distribution of Pseudotormentus De Wever et Caridroit(Radiolaria,Protozoa):Provincialism of a Permian Planktonic Microorganism

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Acta Geologica Sinica(English Edition) 2016年第5期90卷 1598-1610页

作者： ito Tsuyoshi FENG Qinglai MATSUOKA Atsushi State Key Laboratory of Geo-processes and Mineral Resources China University of Geosciences Graduate School of Science and Technology Niigata University Research Institute of Geology and Geoinformation Geological Survey of Japan Department of Geology Faculty of ScienceNiigata University

The Permian planktonic distribution is not well known,in contrast to other fossil distributions of nekton and *** are representative microfossils of plankton in the Permian *** study compares both correlated radiolarian occurrences（Pseudotormentus De Wever et Caridroit and Quadriremis Nazarov et Ormiston） in literature data from the Pacific Rim and quantitative data from the Liuhuang and Gujingling sections in South *** distributions are concentrated in the Panthalassa,whereas Quadriremis occurrences are distributed over both the Panthalassa and the *** uneven distribution of Pseudotormentus seems to have been controlled by a difference in the oceanic basins,indicating the presence of faunal differences in Permian planktonic microorganisms between the Panthalassa and the *** other words,this study infers the provincialism of Permian planktonic *** uneven distribution is explainable by a hypothesis that Pseudotormentus was strongly affected by a Panthalassan equatorial current.

关键词： palaeobiogeography Palaeotethys Panthalassa Permian radiolaria Pseudotormentus Quadriremis

Development of a Leg Mechanism for Soft Landing Based on Biological Motion

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Chinese Journal of Mechanical Engineering 2011年第5期24卷 731-737页

作者： KIMURA Hitoshi OTAKI Yoshihiko ito Shusaku INOU Norio Department of Mechanical and Control Engineering Tokyo Institute of Technology NSK Ltd.

With jumping mechanisms,soft landing motion is important to protect loads and the *** study proposes a leg mechanism for soft landing based on biological *** jumping motion with a load suggests a unique motion for soft *** landing model consists of two *** is minimized in the first period and force is minimized in the second *** comparison with other landing models,this model is specialized for soft landing motion protecting an objective *** all mechanisms have mass,such model is useful in practical *** the purpose of realizing soft landing motion,this study proposes a new leg *** mechanism achieves quick variable transmission with cam and *** process of the cam is explained with dynamics and *** the calculated cam shape,the leg mechanism can be driven by constant input voltage for simple *** against height change is also verified with landing *** 50mm falling experiment,prototype leg mechanism performed soft landing without bounce motion and large *** acceleration profile of the body also agrees with the proposed soft landing model.

关键词： soft landing biological motion leg mechanism cam and wire mechanism

Electron field emission characteristics of nano-catkin carbon films deposited by electron cyclotron resonance microwave plasma chemical vapour deposition

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Chinese Physics B 2008年第2期17卷 716-720页

作者：顾广瑞吴宝嘉金哲 ito Toshimichi Department of Physics College of ScienceYanbian University Division of Electrical Electronic and Information EngineeringGraduate School of EngineeringOsaka University

This paper reported that the nano-catkin carbon films were prepared on Si substrates by means of electron cyclotron resonance microwave plasma chemical vapour deposition in a hydrogen and methane mixture. The surface morphology and the structure of the fabricated films were characterized by using scanning electron microscopes and Raman spectroscopy, respectively. The stable field emission properties with a low threshold field of 5V/μm corresponding to a current density of about 1μA/cm^2 and a current density of 3.2mA/cm^2 at an electric field of 10V/μm were obtained from the carbon film deposited at CH4 concentration of 8%. The mechanism that the threshold field decreased with the increase of the CH4 concentration and the high emission current appeared at the high CH4 concentration was explained by using the Fowler-Nordheim theory.

关键词： field emission carbon films nano-catkin microwave plasma chemical vapour deposition