We investigated the ability of humans to adapt to a novel environment by kinematic transformation. This adaptation was studied via behavioural experiments using a robotic manipulandum – a system designed to arbitrarily generate virtual force fields against a human hand and subsequently record the hand’s trajectory. By repeating motor tasks, this study’s participants gradually learned to move correctly under a newly experienced force field, such as rotating in a clockwise direction. However, each participant’s motor memory was destroyed if he/she experienced an

field (e.g., in a counterclockwise direction) immediately after learning the initial movement, which is known as retrograde interference. In some previous studies, it has been considered that by presenting sensory cues to highlight the difference in two fields, participants can learn both force fields independently without interference. In this study, we investigated the functionality of olfactory cues – specifically lemon and lavender odors – in reducing retrograde interference. Forty-five university students participated in an experiment using a robotic manipulandum. Our results have shown that the presence of lemon odor reduces the destruction of motor memory, while that of lavender did not, suggesting that odors can enhance simultaneous motor learning but the effect depends on the type of odor used.

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[Purpose] In the present study, we investigated femoral muscle activity during toe-gripping, and the role of the femoral muscles in toe-gripping strength. [Subjects] Fourteen healthy young women were selected. [Methods] We measured the maximum voluntary contraction of the rectus femoris and long head of the biceps femoris muscles. We then calculated the percent integrated EMG (%IEMG) during the toe-gripping action. [Results] We found that the %IEMG of the biceps femoris was significantly higher than that of the rectus femoris. Moreover, a significant positive correlation was found between the %IEMG of the rectus femoris and that of the biceps femoris. [Conclusion] These results suggest that femoral muscles co-contract during the toe-gripping action, and thus possibly contribute to knee joint stability.

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The liquid retention properties of wool fibers were investigated for those structurally modified by chemical and mechanical processes, such as treating with solvents and enzyme, heating in 8.0M LiBr solution and stretching in steam.
The extraction of nonkeratinous proteins with organic solvents and pronase was found to cause an increase in the liquid retension of wool fiber. Particularly, the removal of nonkeratinous proteins had marked effects on the retractive forces opposing the swelling pressure of the liquid in the cell membrane complex.
The supercontracted wools in which the original oriented α-structure was transformed to disoriented β-structure in the microfibril, had high liquid retension values at pH2 and 8, distant from the iso-electric point, pH5, whereas the stretched wools in which the oriented β-structure was effected, was little affected in the liquid retention throughout the pH range examined. These results suggest that the extent of the liquid retention of wool is dependent not on the secondary structure of the microfibrillar peptide chains, but on the orientation of the peptide chains which is closely associated with the retractive forces opposing the swelling pressure of liquid in the microfibril.

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The passive forces acting against the drive force are phenomena that influence dynamical properties and precision of linear axes equipped with feed drives. Covers are one of important sources of passive forces in machine tools. The paper describes virtual evaluation of cover passive forces using the cover complex model. The model is able to compute interaction between flexible cover segments and sealing wiper. The result is deformation of cover segments and wipers which is used together with measured friction coefficient for computation of cover total passive force. This resulting passive force is dependent on cover position. Comparison of computational results and measurement on the real cover is presented in the paper.

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We developed a soft-rigid variable gripper capable of grasping heavy objects by combining hydraulic cooling, and electromagnetic motion with soft elements and flexible carbon fibers. We design a Liquid-Cooled Laminar Electromagnet (LCLE) considering its pulling force, size, and working temperature under high payload conditions. The electromagnets were sealed with epoxy resin and cooled forcedly to increment their pulling force. The LCLEs were used to design a gripper with two gripping zones and examined the temperature behavior of the electromagnets when grasping objects of various weights and sizes. A 19 kg mass was grasped to analyze the temperature at different fluid speeds.

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A new mouthguard material, polyolefin, was recently developed. To date, no studies have compared ethylene vinyl acetate (EVA) and polyolefin mouthguards. The aim of this study was to evaluate the physical properties of polyolefin, relative to those of EVA. Two polyolefin materials, hard and regular, were used, in addition to EVA. Hardness, tensile strength, tear strength, elongation, and water absorption were analyzed, as well as the adhesive strength of the materials in laminated mouthguards. Hard polyolefin (MG-H) and EVA were significantly harder than regular polyolefin (MG-R) (p<0.01). Regular polyolefin had significantly lower tensile and tear strengths than MG-H and EVA (p<0.01), while MG-H had significantly higher tensile and tear strengths than EVA (p<0.01). Both polyolefin materials had significantly lower water absorption and higher adhesive strength than EVA (p<0.01). In this study, polyolefin exhibited satisfactory physical properties when compared with EVA. This suggests that polyolefin is suitable for use as a mouthguard material.

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L1₂-type TM₆RE₈ clusters are distributed in enriched layers of LPSO (long period stacking ordered structure), and shrink in the [0001]_Mg direction. The growth mechanism of LPSOs was investigated from the viewpoint of a local strain field. The strength of out-of plane normal strain of the enriched layer varied with the average radius of solute elements in the layer. The first principle calculation showed that there is a relationship between the average atomic radius of solute elements and the structural relaxation in the clusters. Zn conclusion, it is suggested that the difference of average atomic radius between Mg and solute elements controls the degree of the cluster shrinkage by the displacement of the solute elements, and that it is the dominant factor giving rise to the out-of plane normal strains of the enrichment layers.

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Purpose: The present study investigated the biomechanical stability of three miniplate osteosynthesis configurations used for internal fixation of bilateral mandibular angle fracture (BMAF).

Methods: Standard fracture lines were created in 72 polyurethane mandibles and stabilized with 2.0-mm, 4-hole standard titanium miniplates and monocortical screws. The group descriptions and miniplate configurations were: 2Plates (1-1), 3Plates (1-2) and 4Plates (2-2). The mandibles were subjected to either incisal or molar loads (from both sides in the 3Plates group) up to a force of 120 N. The displacements of the constructs were recorded at each force increment of 10 N. ANOVA and Tukey’s post-hoc tests were used for statistical analysis.

Results: The 2Plates group showed higher displacement under both loading conditions (P < 0.05 for each). The same group reached displacement levels of 1 mm and 3 mm during molar loading and 1 mm, 3 mm, and 5 mm during incisal loading at lower force magnitudes relative to others (P < 0.05 for each).

Conclusion: Bone-plate constructs for BMAFs stabilized with three or four standard miniplates are more likely to provide similar resistance when subjected to incisal or molar loads, in contrast to the two-miniplate configuration, which is relatively more prone to displacement.

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Cement solidification is a conventional technique to solidify spent ion exchange resin. Swell-ing property of the ion exchange resin was investigated theoretically and experimentally, as the first step to improve resin content in a cement package. Swelling pressure of the resin was first formulated based on Gregor's swelling model. It was shown that the pressure depended on such factors as ion exchange capacity, type of func-tional group, crosslinkage and water content. Subsequently, swelling pressures for over forty properties of cation exchange resin (DIAION SK-series) with different exchang capacities, water contents and others were experimentally evaluated using an originally developed method. The pressure changed over a range of 060 MPa, depending on properties of the ion exchange resin. These results were in close agreement with values calculated by Gregor's model, indicating that the swelling pressure could be evaluated without resorting to experiments.

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This work studies a control strategy of screw motion to improve the plasticizing precision for an all-electric injection molding machine (AIMM) based on a biaxial simultaneous motion system. In the standard plasticizing process, a screw retraction before or after the metering phase is proposed to link up with the traditional metering process for reducing the residual pressure at the end of holding and metering, respectively. The modified incomplete plasticizing process is then applied to prevent the potential over-travel of the screw. The incomplete plasticizing process uses a control strategy to obtain a fixed start point for the screw at injection in each cycle. Experimental results showed that both the standard and incomplete plasticizing process improve the visual quality and molded precision of parts.

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Flow patterns of three two-dimensional parallel jets were investigated experimentally. In order to examine the effect of varying the ratio of the velocities in the central and outside jets on flow pattern, detailed measurements of the flow by a hot-wire anemometer and flow visualization by oil film were carried out. The results obtained are as follows. (1) The flow fields near the nozzles can be classified in three patterns of the flow according to the velocity ratio. 82) There is a specific velocity ratio at which the flow is unstable. (3) The flow patterns by means of visualization agree well with those of the streamlines, qualitatively.

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The objective of this study is to illuminate key predictive variables as well as preferences and wishes of Japanese undergraduate students majoring in engineering, in terms of English language education. By means of a questionnaire, relevant data were collected from 120 students at the University of Hyogo in January 2016. To reckon statistical predictors, lambda for nominal variables and gamma for ranked variables were calculated. The results elucidated the following: (1) the degrees of liking English in junior and senior high school days are each predictive of how much the respondent likes English today; (2) the numbers of weekly hours spent studying English at home in junior and senior high school days are predictive of the weekly hours spent studying English at home today; and (3) the degree of how much the respondent likes English today is predictive of his/her score on the proficiency quiz. The survey also highlighted that speaking was the most liked in-class activity among the students, while studying grammar rules was the least favored. With regard to selecting in-class activities, a number of factors such as the students’ age, gender, knowledge level, proficiency (both in native and English languages), interest, personality, in-class “chemistry,” social capital, motivation level, and the field of study should be taken into consideration, in addition to statistical as well as intuitive factors.

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Shipping emissions can cause atmospheric pollution and health issues to residents in port areas. Shipping emission control features have been attempted and implemented throughout the world to mitigate air pollution. In this study, the shipping emissions status in the Port of Yangon and its navigation channels is calculated since it is the largest port and the major hub for ocean-going vessels in Myanmar. The vessel emission estimation model is based on the resistance and power prediction model, and emission volumes of 8 emission pollutants are calculated by classifying the vessel activity phases into voyage, hoteling, and anchorage phases. Then spatial analysis of shipping emission is done to identify the area impacted by high emissions. The highest shipping emissions are found at the Outer Bar area of the Yangon Port, where vessels enter and depart the port as well as may anchor to wait for the tide. To reduce the high emission concentration at the Outer Bar area of the Yangon Port, vessel scheduling should be considered. As the next step, the Port of Yangon should consider establishing an air quality monitoring and measuring system. As a result, emissions can be measured in real time, and such data can be shared with ship operators, terminal operators, and local maritime authorities to improve sustainability efforts such as the air quality documentation system, sustainability reporting and regulatory control. We believe that our study would provide more insights into future research for the Port of Yangon.

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The chemical composition and morphology of M₇C₃ eutectic carbides in 19 mass% Cr–2.8 mass% C white iron with up to 4.7 mass% V additions have been studied. Eutectic colonies are mainly composed of a very fine rod-like carbides at the center and become coarser rod-like or blade-like with increased distance from the center. The volume fraction, size and distribution of rod-like and blade-like carbides in the eutectic colonies are changing with increasing vanadium content in the alloys. The formation of the eutectic colonies of different morphology is the consequence of the segregation of alloying elements in the alloy melt, which was confirmed by EDS analysis of the chemical composition of carbides. Three different compositions of M₇C₃ carbides were found in all tested alloys. The main difference between them is in the amount of chromium and iron and in the degree of their replacement by vanadium. Due to different melt composition in particular zones, the constitutional undercooling, and subsequently the growth rate, will be different, which will induce the formation of eutectic colonies of different morphologies.

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Phase-contrast cinematography was used for the study on the meiotic processes from metaphase I to telophase I in the spermatocytes of several species of grasshoppers, obtaining the following results.
1) The chromosome separation and the changes in spindle and cell diameters in anaphase I were measured on the cine-films. The graph of chromosome separation plotted against time was S-shaped in each spermatocyte examined. In the anaphase the chromosomes approach the spindle poles, while the spindle body elongates definitely, the two processes occurring almost simultaneously.
2) The continuous spindle fibers were clearly observable in the living, anaphasic cells. So these component fibers of the spindle exist in vivo as a morphological reality and are not an artificial product. Furthermore, it was conjectured that the elongation of the continuous fibers results in stretching the spindle in anaphase.
3) The kinetochore paths of the bivalents were followed from metaphase I to the end of anaphase I on the cine-films. They are grouped into two types: i) in which the kinetochores approach to the spindle axis progressively from the start of anaphase to the complete separation of the chromosomal tips, and ii) in which they approach to the spindle axis after moving parallel to or receding a little from the axis at the start of anaphase. In both the types, the kinetochores recede somewhat from the axis just after the separation of the chromosomal tips and then, they move more or less parallel to the spindle axis, till they deviate towards the spindle pole at the end of anaphase.
4) All the results mentioned above seem qualitatively well explained on the following assumption: an autonomous terminalization of the chiasmata is active at the early anaphase I, the chromosomes are carried to the spindle poles by the traction of the chromosomal fibers and the elongation of the spindle, and the chromosomes are affected in the spindle by a force which tends to push them out of the spindle and/or by a body repulsion among them.

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The aim of this study was to measure maximum isometric force under two different conditions: active and passive conditions. The electromyograms (EMGs) were also measured. The elbow flexors of healthy subjects were studied. Six healthy subjects took part in this study. The isometric maximum force and the EMGs of the elbow flexors were measured under two contrasting conditions. The first was a standard isometric measurement in which a subject actively pulled a fixed wire using their elbow flexor at 100% effort (active). In the second case, the subject tried to keep their elbow at 90 degrees of flexion for as long as possible against external forces produced by an electric motor (passive). The highest force values were extracted during the isometric phase when the elbow angles were kept constant. Hence, the elbow angles were also monitored by an electric goniometer in the later measurement. The passive condition resulted in higher forces than the active condition in 4 of 6 subjects. For a subject who showed different maximum forces under the two conditions, the mean (standard deviation) measured maximum forces under active and passive conditions were 285.2 (11.0) N and 300.2 (14.1) N, respectively (p < 0.01). For the EMG, there were no significant differences between the two conditions. In conclusion, the passive condition used in this study enhanced isometric maximum forces compared to that obtained under standard isometric conditions.

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The roughing conditions required to avoid local heterogeneous regions in the final microstructure of high temperature processing (HTP) Nb linepipe steels have been investigated for quasi-compact strip production (CSP) conditions. The influence of strain sequence, rolling temperatures and Mn content on recrystallisation and carbonitride precipitation before and after roughing were studied using laboratory simulation, mathematical modelling and transmission electron microscopy. The roughing conditions necessary to avoid the formation of local heterogeneous regions have been established for HTP steels with an initial grain size of 850 µm. Low Mn Nb–Ti steels experience more sluggish recrystallisation kinetics and are more vulnerable to forming local heterogeneous regions during roughing. To prevent local heterogeneous regions if finishing commences at 900°C, sufficient effective strain is necessary to produce a bulk softened fraction of at least 0.55 in each of the first two roughing passes. If finishing commences at 1000°C, slow air cooling from roughing provides additional time for recrystallisation to go to completion and so prevent the occurrence of local heterogeneous regions. Maintaining the strand temperature as high as possible prior to the commencement of roughing encourages recrystallisation. A roughing start temperature of 1100°C, as opposed to 1075°C, significantly reduces the risk of forming local heterogeneous regions. For the conditions tested, no correlation between softening fraction and carbonitride precipitate characteristics was found. Thus, the influence of Nb on austenite recrystallisation is expected to be due to either solute drag or solute clustering.

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This paper presents a novel approach for active chatter reduction using a motor spindle with integrated magnet actuators. Based on the results of previous studies the design of an active damped prototype is described. The system performance as well as the benefits and drawbacks of this solution are discussed. In order to eliminate the known drawbacks a novel actuator design is introduced. The novel approach integrates the actuator windings into the stator core. Next, strategies for electric and magnetic decoupling of the actuator and motor windings are presented. Subsequently the actuator design is discussed. The force generation and distribution of the damping actuator are calculated via analytical and finite elements analysis (FEA). With the novel approach the mechanical integration of the active damping actuators is simplified significantly. Additionally, the maximal attainable spindle power is increased up to 150% in relation to the previous solution.

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　昭和初期、ジェイムズ・ジョイスが注目を集め、いわゆるジョイス・ブームが起こった。小林秀雄は決してそのブームに乗った本人ではなかった。ばかりか、彼はこれに苦々しい懐疑を抱き続けていた。本稿は、小林の否定の眼を通して見たジョイス・ブームに焦点をあて、それによって昭和初期という時代の一面を照らし出そうという意図を持っている。

　昭和初期は科学歓迎の時代と呼んでもよい。プロレタリア文学がマルクス主義唯物論という科学的客観的立脚点を保持していたとすれば、対する芸術派の方も、ことさらに自らの科学性を主張していた。その中で、ジョイスはまさに科学的文芸の最先端として扱われていたのであった。

　しかし小林にとっては、「意識の流れ」の「科学性」などは問題外であった。彼にはむしろ『ユリシーズ』に表われる「作家の顔」こそが重要であった。現代という捉えどころのない時代を描き、現代人という無性格な人物を描こうとする時、その作品は書く対象のリアリティーの不足による「デカダンス」に陥る、と小林は言う。それを救うのが「思想」であり「倫理」だというのである。ジョイスの「倫理」が、すなわちニヒリスティックな「作家の顔」が『ユリシーズ』を救っている、と小林は見た。

　『ユリシーズ』に見られる「無暗矢鱈に振り廻」された「衒學的な洒落」を取り除いて、小林はジョイスの「作家の顔」を見定めようとした。しかしジョイスにとって「作家の顔」とは、まさに「無暗矢鱈に振り廻」された「衒學的な洒落」そのものではなかっただろうか。つまり、言葉あそびによってジョイスは、現代という摑みどころのない時代の多層的な「リアリティー」を描こうとしたのである。『ユリシーズ』において言葉あそびはもはや技法ではなく、小林いうところの「作家の顔」の具象化されたものであったといってよい。

「ジョイスについては、『ユリシーズ』の佛譯を通じてわずかに知るのみ」という小林が、科学的技法なるものに浮かれる当時のジョイシアン達を否定し、浮薄なジョイス•ブームに懐疑を抱いたのは、彼の文学的直感が卓越したものであったことを物語っている。しかし小林にさえ見ることのかなわなかったものは、ジョイスにとっての、あるいは現代にとっての言葉の位置であった。そしてそれは小林の限界というよりも、おそらくは、言葉そのものの潜在力にまで注意を向け得なかった昭和初期という時代の限界であったといえるかもしれない。

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