著者
干場 恵美子 稲垣 照美 木村 尚美 阿部 宣男 宮内 一美
出版者
The Japan Society of Mechanical Engineers
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.72, no.714, pp.409-417, 2006
被引用文献数
1

The fantastic light of firefly, which keeps fascinating the heart of Japanese from ancient time, and the ecosystem are taken up as one of cure fields being benefit from the nature. In this study, from a viewpoint of Kansei engineering, we focused on the hue of light emission pattern of firefly, and we examined whether it causes the human spirit any effects or not by using various statistical analysis and Kansei analysis. It was revealed that there is a high possibility that the sufficient cure effect exists in the hue of light emission pattern of firefly and the ecosystem. This research is the first basic trial turned to the creation of cure spaces for hospice and welfare facility, which utilize the firefly and the mini ecosystem artificially modeled in an enclosure.
著者
Yoshihiro SEJIMA Tomio WATANABE Mitsuru JINDAI
出版者
The Japan Society of Mechanical Engineers
雑誌
Journal of Advanced Mechanical Design, Systems, and Manufacturing (ISSN:18813054)
巻号頁・発行日
vol.10, no.9, pp.JAMDSM0103, 2016 (Released:2016-11-09)
参考文献数
21
被引用文献数
1

In human interaction and communication, not only verbal messages but also nonverbal behavior such as nodding and paralanguage are rhythmically related and mutually synchronized among speakers. This synchrony of embodied rhythms unconsciously enhances a sense of unification and causes an interaction-activated communication in which nonverbal behaviors such as body movements and speech activity increase, and the embodied interaction is activated. In this paper, we propose the concept of an estimation model of interaction-activated communication based on the heat conduction equation with the characteristics of precipitous speed fluctuation and develop a model that estimates the degree of interaction-activated communication by using speech input only. Further, we evaluate the developed model in estimating the period of the interaction-activated communication in an avatar-mediated communication. The results demonstrate that the developed model is effective in estimating the interaction-activated communication.
著者
Jun YOSHIDA Eito MATSUO Yasuyuki TAKATA Masanori MONDE
出版者
The Japan Society of Mechanical Engineers
雑誌
Mechanical Engineering Journal (ISSN:21879745)
巻号頁・発行日
vol.6, no.3, pp.18-00388, 2019 (Released:2019-06-15)
参考文献数
8

This paper introduces a new hydrogen refueling system with a micro-scale hydrogen turbo-expander that enables us to replace a conventional low temperature refrigerator. From the process simulation of hydrogen refueling to the tank of a typical Fuel Cell Vehicle (FCV), the system is thermodynamically verified to be capable of refueling 5 kg-H2 within 3 minutes by the direct expansion in the micro-scale hydrogen turbo-expander. For the realization of this new concept, a process design approach of a high pressure hydrogen refueling system with the micro-scale hydrogen turbo-expander is described. In this process design, a turbine-compressor type is adopted to the micro-scale hydrogen turbo-expander unit, and an extracted power from the turbine side is consumed as a compressor power which is equipped on the opposite side of the turbine rotor. As a consequence of the thermodynamic analysis and simulation for the proposed system including the turbo-expander with adiabatic efficiency around65 %, it reveals that the new system provides some significant advantages compared with the conventional process. From a feasible investigation of this system, several advantageous features such as 1) high energy conservation, 2) compactness, 3) initial cost and operation cost, and, 4) system expandability (modification for shorter time refueling) are also described when it is compared with the existing system.
著者
Masaharu KOMORI Kippei MATSUDA Tatsuro TERAKAWA Fumi TAKEOKA Hideaki NISHIHARA Hiroo OHASHI
出版者
The Japan Society of Mechanical Engineers
雑誌
Journal of Advanced Mechanical Design, Systems, and Manufacturing (ISSN:18813054)
巻号頁・発行日
vol.10, no.6, pp.JAMDSM0086, 2016 (Released:2016-10-24)
参考文献数
31
被引用文献数
6 8

A transportation vehicle or mobile robot that can move to a target location in an arbitrary direction on the floor is important to ensure that work can proceed quickly and effectively in a limited space. To move in an arbitrary direction, conventional methods such as omni wheels have free rollers along the outer circumference of the wheel that can rotate passively. However, the conventional methods are difficult to control precisely because of the rotational resistance of the free rollers. In addition, the direction that the conventional methods can move actively by themselves is limited. This paper proposes a novel mechanism called the active omni wheel, which is able to actively move in an arbitrary direction by using only one wheel unit. The active omni wheel is composed of a main body and outer rollers arranged around the outer circumference of the wheel. By using a differential gear mechanism, the active omni wheel enables active rotation of not only the main body of the wheel but also the outer rollers. The theoretical equation of motion of the active omni wheel is clarified to control the wheel. An omnidirectional vehicle using the active omni wheel is discussed. The appropriate arrangement of wheels that enables the omnidirectional vehicle to move actively in arbitrary directions by using the active omni wheel is shown and the motion theory is constructed. This paper also discusses the structure appropriate for the vehicle using the active omni wheel, including the arrangement of input shafts, the structure supporting the wheels, the main body of the vehicle, and its suspension. The active omni wheel and omnidirectional vehicle were designed and manufactured. Experiments conducted on the manufactured vehicle verify the effectiveness of the active omni wheel and the omnidirectional vehicle.
著者
山田 敏郎 可児 弘毅 生田 耕治
出版者
The Japan Society of Mechanical Engineers
雑誌
日本機械学会論文集 B編 (ISSN:03875016)
巻号頁・発行日
vol.47, no.415, pp.450-460, 1981

衝撃超高圧力研究用に超高速飛しょう体発射装置(二段式軽ガス銃)が試作され, その性能の数値解析が試みられた. 試作装置により16.4gの飛しょう体が3.57km/sまで加速・発射された. 発射実験結果と性能解析の予想値との良い一致により, 解析法の妥当性が確かめられた. 性能解析により, 試作装置は9.5gの飛しょう体が5km/sまで加速できることおよび発射速度支配因子のうち, 特に装薬量と飛しょう体質量の影響が大であることなどが明らかにされた.
著者
橋本 良夫 斉藤 敏克
出版者
The Japan Society of Mechanical Engineers
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.69, no.687, pp.3029-3033, 2003

A method is proposed to analyze dynamic response of a rocket-launcher system at lift-off. In this paper, rocket-launcher system is modeled as finite element Bernoulli-Euler beams connected with two slippers which are modeled as linear springs. A beam element with a moving spring is devised to represent the rocket-launcher interaction. Coupled equations of motion with time-varying coefficients are derived and solved by using direct method such as the Wilson θ method to calculate the dynamic response of the system. To verify the validity of this method, dynamic response is calculated by using the data of M-3S rocket-launcher system. Two rocket models, rigid-body and elastic-body models, are used in this calculation. The numerical results obtained from two models are compared and discussed.
著者
Michio Yamawaki Yuji Arita Takayuki Terai Tadafumi Koyama Koichi Uozumi Yuma Sekiguchi Masami Taira
出版者
The Japan Society of Mechanical Engineers
雑誌
Proceedings of the ... International Conference on Nuclear Engineering. Book of abstracts : ICONE (ISSN:24242934)
巻号頁・発行日
pp._ICONE23-1, 2015-05-17 (Released:2017-06-19)
被引用文献数
1 1

Source term for severe accident analysis of molten salt reactors(MSRs) has been investigated as part of preliminary efforts to develop MSRs. As a severe accident of MSRs, exposure of heated fluoride fuel molten salt to atmosphere was assumed to take place. Vaporization of fluoride molten salt was studied by means of the two methods, the Knudsen effusion mass spectrometry as well as the transpiration method. The former was applied to pseudo-binary fluoride systems to clarify the behaviors of cesium and iodine in the fluoride molten salt. The latter was applied to the mixture of CsI and FLiNaK. These experiments were carried out as the first step of the source term studies, so that interaction with air components has not been covered yet. From this study, useful information related to the source term for MSRs have been obtained. This work suggests how to solve the problem to establish the source term for severe accident analysis of MSRs.
著者
Shinichiro UESAWA Susumu YAMASHITA Mitsuhiko SHIBATA Hiroyuki YOSHIDA
出版者
The Japan Society of Mechanical Engineers
雑誌
Mechanical Engineering Journal (ISSN:21879745)
巻号頁・発行日
vol.5, no.4, pp.18-00115, 2018 (Released:2018-08-15)
参考文献数
17

A dry method is one of fuel debris retrieval methods for decommissioning of TEPCO’s Fukushima Daiichi nuclear power station. However, the cooling of fuel debris must be fully maintained without water. Japan Atomic Energy Agency (JAEA) has evaluated the air-cooling performance of the fuel debris in the dry method by using JUPITER. Because JUPITER can represent the relocation of the corium, the unknown parameters, such as the composition and the position of the fuel debris at the RPV pedestal, can be reduced. By calculating the heat transfer of the fuel debris based on the corium relocation obtained with JUPITER, more accurate analysis of the air-cooling performance of the fuel debris in the dry method is expected. In order to evaluate the air-cooling performance of fuel debris in the dry method by using JUPITER, the validation of the free-convective heat transfer analysis of JUPITER were performed in this paper. In order to qualitatively evaluate results of JUPITER for configurations closer to experimental conditions and to decide physical values and positions to be measured in the validation, JUPITER was compared with OpenFOAM for the simple cuboid configuration which has the heating and cooling surfaces at the floor and the ceiling, respectively. The comparison proved that JUPITER can calculate the vertical temperature distribution as well as OpenFOAM on the condition of the lower heating amount. In the validation, JUPITER was compared with the heat transfer experiments of free convection in air adjacent to an upward-facing horizontal heating surface. The comparison proved that JUPITER was in good agreement with the experiment on the condition of the lower heating-surface temperature. The result indicated that JUPITER is a helpful numerical method to evaluate the free-convective heat transfer of the fuel debris in the dry method.
著者
Masahiro KANAZAKI Kai TOMISAWA Koji FUJITA Akira OYAMA Hiroki NAGAI
出版者
The Japan Society of Mechanical Engineers
雑誌
Journal of Fluid Science and Technology (ISSN:18805558)
巻号頁・発行日
vol.14, no.3, pp.JFST0017, 2019 (Released:2019-12-19)
参考文献数
11

We redesigned the Mars Airplane Balloon Experiment Two (MABE-2) based on MABE-1 to improve the vehicle’s stability and controllability. Following the redesign, the MABE-2 vehicle had a larger horizontal tail volume than that of MABE-1 for improved stability performance. In addition, to further improve the stability and control characteristics, a rectangular planform was employed for the horizontal tail wing; in contrast, MABE-1 had a tapered planform. The vertical tail position of MABE-2 was moved to the end of the horizontal tail wing, because the vertical tail of MABE-1, which was positioned at the mid span of the horizontal tail wing, showed aerodynamic interaction with the horizontal tail wing. In this paper, we discussed the aerodynamic performance of a control surface based on computational fluid dynamics with variation in the deflection angle between the control surface and the horizontal tail (elevator), and we examined the effects of this redesign on longitudinal control characteristics. Numerical investigations confirmed the linear variation in the pitching moment and the aerodynamic force with the changing elevator deflection angle in MABE-2. Surface pressure observations indicated that MABE-2 shows a smooth variation in the pressure distribution with changing elevator deflection angle, while MABE-1 does not. These results demonstrate that the aerodynamic control characteristics of MABE-2 were improved in comparison to those of MABE-1.
著者
Naoki MORITA Kazuo YONEKURA Ichiro YASUZUMI Mitsuyoshi TSUNORI Gaku HASHIMOTO Hiroshi OKUDA
出版者
The Japan Society of Mechanical Engineers
雑誌
Mechanical Engineering Letters (ISSN:21895236)
巻号頁・発行日
vol.2, pp.16-00082, 2016 (Released:2016-03-03)
参考文献数
9

Structural elements which have 6 degrees of freedom (DOFs) at each node, such as shell and beam elements, are widely used in structural analysis. A matrix originating from finite element method (FEM) is stored in some sparse matrix storage format with a suitable block size for the number of DOFs at each node. When both 6 DOF structural elements and general 3 DOF solid elements are employed, the sparse matrix storage format becomes complicated due to combination of different block sizes. High computational efficiency of finite element analysis has become more important in large-scale structural problems. The complicated storage format leads to deterioration of computing performance in solving linear equations by an iterative procedure, conjugate gradient (CG) iterations for example. A computational technique is required that allows us to use existing parallel linear solvers without deteriorating the performance for solving linear equation systems originating from combination of solid and structural elements. This research aims to develop 3×3 DOF blocking structural elements to enhance the computational intensity of iterative linear solver, such as the CG method. As numerical results, the proposed 3×3 DOF blocking elements have shown better performance for each CG iteration than the conventional structural elements. The computational efficiencies are 95.0% with single thread execution and 76.6% with 8-thread execution of a theoretical peak performance based on the STREAM benchmark.
著者
Seiichi SUDO Koji TSUYUKI Junji TANI
出版者
The Japan Society of Mechanical Engineers
雑誌
JSME International Journal Series C Mechanical Systems, Machine Elements and Manufacturing (ISSN:13447653)
巻号頁・発行日
vol.43, no.4, pp.895-900, 2000-12-15 (Released:2008-02-18)
参考文献数
11
被引用文献数
20 24

This paper describes detailed wing morphology of some kinds of insects. The structural properties of dragonfly, fly, and mosquito wings were studied. Microscopic observations on the insect wings were examined with a scanning electron microscope. The surface roughness of the insect wings was measured by a three-dimensional, optical shape measuring system. The roughness distribution on the wing surface was presented for some kinds of insects. Some functional principles underlying insect wing design were revealed by the measurements of surface roughness and microscopic observations.
著者
Yutaro MOTOORI Susumu GOTO
出版者
The Japan Society of Mechanical Engineers
雑誌
Journal of Fluid Science and Technology (ISSN:18805558)
巻号頁・発行日
vol.14, no.3, pp.JFST0016, 2019 (Released:2019-12-19)
参考文献数
16

Coarse-graining is indispensable for extracting a hierarchy of vortices in fully developed turbulent flow with multiscale nature. In the present study, for a high-Reynolds-number turbulent boundary layer, we employ two simple coarse-graining methods in real space; namely, a Gaussian filter and the combination of the Gaussian filters at two scales. The former corresponds to a low-pass filter of Fourier modes, while the latter corresponds to a band-pass filter. We also examine two different filter widths for the band-pass filter. Then, we show difference in the statistics of the three filtered fields. Since the velocity gradients in turbulence are mainly determined by the smallest-scale motions, vortical structures identified by the second invariant Q of the velocity gradient coarse-grained by the filters are similar. However, there is difference between low- and band-pass filtered fields in the contribution to the enstrophy production rates. This is because the production rates are determined not only by the magnitude of the strain rates but also by the alignment between the vorticity and the stretching direction. In addition, since vortices are not created in the entire system, the conditional sampling by the value of Q is essential to understand the generation mechanism of the hierarchy of vortices. The conditional analysis of the band-pass filtered fields demonstrates that small-scale vortices in the log layer are stretched by twice-larger vortices, whereas they weaken the twice-larger vortices. This observation is consistent with the picture of the energy cascade. We also show that when using the band-pass filter, these conclusions are robust irrespective of the choice of the filter width.
著者
鈴木 曠二
出版者
The Japan Society of Mechanical Engineers
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.50, no.457, pp.1736-1739, 1984

The Dynamic Soaring is the soaring technique making use of the wind gradient. The order, Albatross belongs to, includes several species which use this technique and have various scale. Main conclusion is as follows: They practice almost physically similar dynamic soaring. The larger one practices a larger dynamic soaring and requires a stronger wind than the smaller one does, in the wind near the sea surface. Such a scale effect corresponds with the fact that a Wandering Albatross lives in the zone of the westerlies of the Southern hemisphere; on the other hand, a Streaked Shearwater which is smaller than it lives in areas where it is not so windy. But if the wind profile was almost linear, the said relation between the scale of a bird and the wind strength would be reversed.
著者
Vitor Mitsuo FUKUSHIGUE HAMA Wei WU Mutsunori YAGIURA
出版者
The Japan Society of Mechanical Engineers
雑誌
Journal of Advanced Mechanical Design, Systems, and Manufacturing (ISSN:18813054)
巻号頁・発行日
vol.12, no.3, pp.JAMDSM0072, 2018 (Released:2018-07-20)
参考文献数
29

The overall planning process undertaken by a bus company is traditionally composed of five sub-processes: timetabling, vehicle scheduling, maintenance scheduling, crew scheduling, and crew rostering. Solving the full optimization problem is believed to be computationally intractable, and therefore in practice the five sub-processes are usually optimized in sequence. In this paper, we present a model that integrates the problems of vehicle scheduling and maintenance scheduling. The objective is to minimize the differences in mileage between buses, the total distance traveled, and the daily differences in the number of maintenance tasks. We propose a heuristic algorithm using the framework of greedy randomized adaptive search procedure (GRASP), and we improve the neighborhood search procedure by using an ordered list of possible trips. We compare the neighborhood search procedure with and without this mechanism and show that the ordered list reduces the number of neighbors to be checked by more than 95%, and it reduces the time to obtain solutions of the same or better quality by an average of 70%. Through computational experiments on instances generated from real-world data, we show that the proposed algorithm finds solutions that are as good as or better than those obtained by a commercial solver in less than 5% of the time required by the latter.
著者
田辺 実 常盤 匡 小泉 忠由
出版者
The Japan Society of Mechanical Engineers
雑誌
日本機械学会論文集 (ISSN:21879761)
巻号頁・発行日
vol.80, no.817, pp.DSM0274-DSM0274, 2014

The relationship between the elements included in materials and the fire ball obtained by spark test, that is simple, has been examined by using SEM photographing of the fire ball. From experimental results, the kind of steel material could be estimated from fireballs image of SEM. The following contents would be pointed out as the results. The size of fire ball becomes large with the increase in the contained carbon. The size of alloy steels becomes about the double of fire ball of carbon steel. When nickel element is contained in a material, the surface of fire ball shows the delamination. When the many chromium components are contained the size of fire ball becomes large, and many holes occur in the fireball. The presence of molybdenum element in the steel shows the smooth texture at the surface of the fireball. The wrinkles appear at the surface of the fireball by the presence of tungsten element, and the many holes occur in the fireball. Whether the material is ductile or brittle we would be estimated from the pattern of deformation of the hole of the fire ball. The kind of material would be able to distinguish from the qualitative properties of the fire ball.
著者
古谷 正広 太田 安彦 北口 佳範 大崎 守 村井 美樹 磯貝 鉄也
出版者
The Japan Society of Mechanical Engineers
雑誌
日本機械学会論文集 B編 (ISSN:03875016)
巻号頁・発行日
vol.67, no.662, pp.2625-2631, 2001
被引用文献数
3

Compression ignition of a stoichiometric iso octane/oxygen/argon mixture was observed using a shock tube and a rapid compression machine. Reducing the compression temperature, the activation energy for the shock compression ignition fell suddenly at the critical temperature the ignition delay exceeded around 1 ms. This peculiarity could be seen in the shock compression stoichiometric methane ignition with which mixture absolutely no cool flame low-temperature reactions accompanied. Shock wave diagrams indicated that the ignition was originated not at the end of the tube but to the inside of the tube. It resulted in the smaller activation energies in the lower temperature regions. This phenomenon was not due to the difference of chemical reaction mechanisms. IIigh-speed schlieren observations using another shock tube with visualization windows have allowed us to confirm the peculiarity that the earliest ignition sites were located apart from the tube end and the ignition initiation structure would change depending on the compression temperature.
著者
Masateru MAEDA Hao LIU
出版者
The Japan Society of Mechanical Engineers
雑誌
Journal of Biomechanical Science and Engineering (ISSN:18809863)
巻号頁・発行日
vol.8, no.4, pp.344-355, 2013 (Released:2013-12-24)
参考文献数
15
被引用文献数
10 13

In very few studies it is shown that an increase in vertical force can be achieved when a flapping-wing hovers in ground effect (IGE). The body, however, has usually been neglected and its influence on three-dimensional vortex structures and consequent aerodynamic forces is still unclear. In this study we carried out a computational fluid dynamic study of a fruit fly (Drosophila melanogaster) hovering for two cases: “in ground effect” and “out of ground effect” (OGE), where the heights from the ground are less than one and more than five times the wing length, respectively. The wings in the IGE computation generated merely 0.7% larger wingbeat cycle-averaged vertical force than in the OGE condition. The body, in contrast, exhibited a significant increase in the vertical force: when out of ground effect, the average vertical force of the body was almost zero (-0.0025 μN); whereas in ground effect, the force increased to 0.78 μN, which is the major contributor to the 8.5% increase in the total vertical force (from 9.9 μN at OGE to 10.8 μN at IGE). Meanwhile, the aerodynamic power of the wings decreased by 1.6%, resulting in a 10% improvement in the overall vertical force-to-aerodynamic power ratio. The flow-field visualization revealed that the downwashes generated by the wings create a high pressure “air cushion” underneath the body, which should be responsible for the enhancement of the body vertical force production. Our results point to the importance of the presence of body in predicting the vertical forces in flapping flights in ground effect.
著者
Kunihiko ICHIKAWA
出版者
The Japan Society of Mechanical Engineers
雑誌
Bulletin of JSME (ISSN:00213764)
巻号頁・発行日
vol.11, no.47, pp.857-865, 1968 (Released:2008-02-15)
参考文献数
2
被引用文献数
64

Finding a train operation which minimizes energy consumption for leading the train from one station to the next at the specified instant and stopping it there is dealt with in this paper. Since speed limit is observed strictly in the train operation, the problem should be considered as a bounded state variable problem. It is true that solving a bounded state variable problem is universally considered extremely troublesome, but the author has recently developed a very simple and clear method. The method is applied to this problem and the optimal control law has really been obtained straightforward and definitely. The author's is again confirmed to be very convenient to solve a bounded state variable problem. The research is believed to be the first scientific research on the economization of train operation.
著者
Shohei TAKAOKA Tsutomu KAIZUKA Bo YANG Kimihiko NAKANO
出版者
The Japan Society of Mechanical Engineers
雑誌
Mechanical Engineering Journal (ISSN:21879745)
巻号頁・発行日
vol.7, no.2, pp.19-00572, 2020 (Released:2020-04-15)
参考文献数
28

Methods for presenting information by utilizing a visual field (such as driver peripheral vision) are attracting increased attention in association with an increase in the amount of information required for driver assistance. However, studies on interfaces utilizing such a visual field are currently insufficient. In addition, to avoid information overload, it is important to evaluate different interfaces in terms of the amount of information presented. The authors researched those interfaces from the viewpoint of ergonomics with the purpose that the result is possible to be applied to various researches mainly in the field of automobiles. Through an in-house experiment, participants viewed video clips presenting dot patterns within their peripheral vision or effective visual field (which is nearer to the gazing point than peripheral vision), and then answered questions regarding the positions and moving directions of the dots and the mental workload they experienced. The authors prepared two types of dotted patterns (fixed and moving) based on the perceptive characteristics of peripheral vision. The number of dots varied from one to six. The rate of misperception and participant mental workload were calculated. The results showed a tendency for the effect of the visual fields to depend on the type of dot pattern. It appears that the interface for peripheral vision may have resulted in a lower accuracy when fixed objects were presented, whereas fewer differences occurred when moving dots were shown. This implies that information with motion can be more suitable for interfaces utilizing peripheral vision. A larger amount of information and number of tasks resulted in lower accuracy and higher workload. Moreover, the relation between the number of dots and the rate of misperception (estimated based on percentage) suggests that the rate of misperception may increase significantly when either four or more fixed objects, or three or more moving objects, are presented.