A Framework for a Large-Scale Machine Tool With Long Coarse Linear Axes Under Closed-Loop Volumetric Error Compensation

A large-scale machine tool is typically very inefficient in size, cost, and energy consumption. Some large parts only have a set of machining features, each of which is within a small local region, and their location should meet position and orientation tolerances. In such a machining application, as a more cost- and energy-effective alternative, this paper presents the concept of a “portable” machine tool, where a small machining platform, with the capability to machine each local machining feature in the required accuracy, is moved by long coarse linear axes. The coarse axes only perform the point-to-point positioning to each machining feature and fixed by servo control during the machining. They do not have sufficient positioning repeatability. To ensure the position/orientation accuracy of each machining feature without having highly repeatable coarse axes, this paper proposes the application of a tracking interferometer to measure all the error motions of coarse axes, and then to perform their compensation. This can be seen as a closed-loop feedback control for coarse axes using the tracking interferometer in the loop. The proposed concept is demonstrated by the experiments with its prototype using a six-degrees of freedom robot moved by two coarse linear axes

Molecular Basis on Nitrogen Utilization in Rice(Recent Topics of the Agricultunal Biological Science in Tohoku University)

Rice (Oryza sativa L.) is the major provision for half of the world population and is the important model crop in terms of synteny. Nitrogen is a massive prerequisite element for rice during its life span. During evolutionary processes, rice has acquired strategic systems of nitrogen metabolism for the survival, i.e., the highly efficient ammonium assimilation in roots and nitrogen remobilization (nitrogen recycling). In our laboratory, research is underway to elucidate molecular mechanisms, cellular functions and the communication mechanisms in nitrogen metabolisms, especially ammonium assimilation in roots and nitrogen recycling, in rice. In this article, aim and overview of our research projects, and some recent research topics are shown

Kinematic modeling and error sensitivity analysis for on-machine five-axis laser scanning measurement under machine geometric errors and workpiece setup errors

On-machine scanning measurement of workpiece geometry has a strong advantage in its efficiency, compared to conventional discrete measurement using a touch-trigger probe. When a workpiece is rotated and tilted, position and orientation errors of the workpiece with respect to the machine’s rotary axes can be a significant contributor to the measurement error. Rotary axis geometric errors also influence the measurement error. To establish the traceability of on-machine measurement with workpiece rotation, this paper kinematically formulates their contribution to measured profiles. As a practical application example, this paper presents the measurement error assessment for an axis-symmetric part. Based on the present kinematic model, this paper compares error contributors to the cases (1) where an axis-symmetric part is placed concentric to the rotary axis, and (2) where it is placed away from the rotary axis

An Attempt about the Active Learning Class "Nursing Care": KUSEP Program for the Study of Japanese Culture and Society "Nursing Care to Elderly People in Japan"

本稿では日本文化・社会学習プログラムの授業科目として，2015年度秋学期より開講されている「日本における介護福祉の現状」について，これまで三学期間にわたり実施してきた授業の内容と変遷を報告している。この授業では，講義として日本の介護福祉の現状を学ぶとともに，留学生が実際に介護福祉施設を訪れ，高齢者と触れ合ったり現場の状況を肌で感じたりすることを目的としている。日本の高齢者と交流することは，留学生にとって貴重な体験であり，学習後に学生が提出する感想文の内容から，今後の課題についても述べている。The number of international students at Kanazawa University is increasing every year, and the International Student Center holds many active learning classes for various themes of Japanese culture and society. The author has experience to work in the field of nursing care, therefore he started the active learning class "Nursing Care to Elderly People in Japan" in Autumn Semester 2015. At the university, the international students rarely have the opportunity to come in contact with elderly Japanese people, therefore this class gives them a good chance to talk to and communicate with old people in Japanese, which may be something different from the language they read in their textbooks. And they also have the chance to learn about nursing care systems for aged people, and about the problems of an aging society. In this class, most of the international students are from China and Southeast Asian countries. In general, these students have no clear idea about these serious problems, and so it is very important for them to realize these problems. In this paper the author describes the outline of the class for three semesters, from Autumn Semester 2015 to Autumn Semester 2016, and introduces the international students\u27essays about their experiences at the Nursing Care Facilities, to make clear the significance and improvement points of this class

Disruption of a Novel NADH-Glutamate Synthase2 Gene Caused Marked Reduction in Spikelet Number of Rice

Inorganic ammonium ions are assimilated by a coupled reaction of glutamine synthetase and glutamate synthase (GOGAT). In rice, three genes encoding either ferredoxin (Fd)-GOGAT, NADH-GOGAT1, or NADH-GOGAT2, have been identified. OsNADH-GOGAT2, a newly identified gene, was expressed mainly in fully expanded leaf blades and leaf sheaths. Although the distinct expression profile to OsNADH-GOGAT1, which is mainly detected in root tips, developing leaf blades, and grains, was shown in our previous studies, physiological role of NADH-GOGAT2 is not yet known. Here, we isolated retrotransposon mediated-knockout mutants lacking OsNADH-GOGAT2. In rice grown under paddy field conditions, disruption of the OsNADH-GOGAT2 gene caused a remarkable decrease in spikelet number per panicle associated with a reductions in yield and whole plant biomass, when compared with wild-type (WT) plants. The total nitrogen contents in the senescing leaf blade of the mutants were approximately a half of the WT plants. Expression of this gene was mainly detected in phloem companion cells and phloem parenchyma cells associated with large vascular bundles in fully expanded leaf blades, when the promoter region fused with a β-glucuronidase gene was introduced into the WT rice. These results suggest that the NADH-GOGAT2 is important in the process of glutamine generation in senescing leaves for the remobilization of leaf nitrogen through phloem to the panicle during natural senescence. These results also indicate that other GOGATs, i.e., NADH-GOGAT1 and ferredoxin-GOGAT are not able to compensate the function of NADH-GOGAT2