（2018年4月～2019年3月の期間で集計）
＊順位の変動は2018年1月～2018年12月の期間との比較

 

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Large eddy simulation with modeled wall-stress: recent progress and future directions

Johan LARSSON, Soshi KAWAI, Julien BODART, Ivan BERMEJO-MORENO

Mechanical Engineering Reviews　（2016）　DOI:10.1299/mer.15-00418

The paper provides a brief introduction to the near-wall problem of LES and how it can be solved through modeling of the near-wall turbulence. The distinctions and key differences between different approaches are emphasized, both in terms of fidelity (LES, wall-modeled LES, and DES) and in terms of different wall-modeled LES approaches (hybrid LES/RANS and wall-stress-models). The focus is on approaches that model the wall-stress directly, i.e., methods for which the LES equations are formally solved all the way down to the wall. Progress over the last decade is reviewed, and the most important and promising directions for future research are discussed.

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Prospect and Recent Research & Development for Civil Use Autonomous Unmanned Aircraft as UAV and MAV

Kenzo NONAMI

Journal of System Design and Dynamic　（2007）　DOI:10.1299/jsdd.1.120

This paper describes the present state of research and development for civil use autonomous unmanned aircraft. In particular, the history of civil use UAVs, the research and development in the world and in Japan, and the subjects and prospects for control and operation systems of civil use autonomous UAVs are described.

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Effect of seam characteristics on critical Reynolds number in footballs

Kiyoshi NAITO, Sungchan HONG, Masaaki KOIDO, Masao NAKAYAMA, Keiko SAKAMOTO, Takeshi ASAI

Mechanical Engineering Journal　（2018）　DOI:10.1299/mej.17-00369

In recent years, the design of footballs, including the number and shape of the panels forming the surface of footballs, has undergone a significant change. However, panels of varied shapes and seams are combined in complex ways to form the surface shape of footballs, and almost nothing is known about the effect of these surface shapes on the football drag characteristics. The present study used a wind tunnel to study the relationship between the critical Reynolds number and the length, depth, and width of the panel joints (seams) of 10 most recent football types used in matches in recent years. The results show the tendency that the drag coefficient in the super-critical regime (30 m/s) of a football increases as the panel joint length increases. Moreover, the depth of the panel joint indicates the highest correlation with the critical Reynolds number (r = –0.71, p < 0.01) and is considered to be a strong and convenient indicator that expresses the roughness (large scale) of the football surface. This study reveals the drag characteristics of the latest footballs and enables some degrees of prediction of the critical Reynolds number for the latest football types and those that will be developed in the future.

4位 [↑]	A Review on High-Speed Machining of Titanium Alloys Mustafizur RAHMAN, Zhi-Gang WANG, Yoke-San WONG JSME International Journal Series C Mechanical Systems, Machine Elements and Manufacturing　（2006）　DOI:10.1299/jsmec.49.11
5位 [↑]	Direct numerical simulations of bubbly flows Gretar TRYGGVASON, Jiacai LU Mechanical Engineering Reviews　（2015）　DOI:10.1299/mer.15-00220
6位 [↑]	Development of measurement technique of mass diffusion coefficient of aqueous methanol solutions in polymer electrolyte membranes based on infrared Soret forced Rayleigh scattering method using single crystal diamond window in a sample cell Hiroaki MATSUURA, Daichi TOKUDA, Yuji NAGASAKA Journal of Thermal Science and Technology　（2018）　DOI:10.1299/jtst.2018jtst0015
7位 [NEW]	Optimizing successful balance recovery from unexpected trips and slips Matthew A BRODIE, Yoshiro OKUBO, Daina L STURNIEKS, Stephen R LORD Journal of Biomechanical Science and Engineering　（2018）　DOI:10.1299/jbse.17-00558
8位 [NEW]	Stress intensity factor of a penny-shaped crack with small-disturbed crack front line Masayuki ARAI Mechanical Engineering Journal　（2018）　DOI:10.1299/mej.18-00244
9位 [NEW]	Recent developments on refined theories for beams with applications Erasmo CARRERA, Alfonso PAGANI, Marco PETROLO, Enrico ZAPPINO Mechanical Engineering Reviews　（2015）　DOI:10.1299/mer.14-00298
10位 [NEW]	Design of cylindrical honeycomb cores – Geometric consideration – Sachiko ISHIDA Mechanical Engineering Journal　（2018）　DOI:10.1299/mej.18-00147