A Multiple-Output Current Mirror with Neuron MOSFETs

Akio Shimizu,Yuki Nobe,Yohei Ishikawa,Sumio Fukai 대한전자공학회 2009 ITC-CSCC :International Technical Conference on Ci Vol.2009 No.7

In this paper, we propose a multiple-output current mirror with neuron MOSFETs. The proposed circuit is composed of a transimpedance amplifier with multiple-output. Consequently, the proposed circuit has high current copy accuracy and a high output swing. Then the proposed circuit has two output terminals for a high performance operational amplifier and a high resolution digital-to-analog converter. The proposed circuit is designed by using the device parameter of the standard CMOS 1.2㎛ process. The performance of the proposed circuit is evaluated by HSPICE simulation. Simulation results show that the error rate of current copy in the proposed circuit is ±0.001[%] when output voltage is 0.13[V] and over.

Fast Evaluation of Period Deviation and Flatness of a Linear Scale by Using a Fizeau Interferometer

김우재,Yuki Shimizu,Akihide Kimura,Wei Gao 한국정밀공학회 2012 International Journal of Precision Engineering and Vol. No.

A reflective-type linear scale with a pitch of 1.67 m used in an interferential scanning-type 2-DOF linear encoder is evaluated by the Fizeau interferometer with a measurement range of 100 mm. The 2-DOF linear encoder produces 2-axis position signals based on the interference between the X-directional positive and negative first-order diffracted beams from the linear scale. Firstly, the Z-directional flatness eZ(x,y) of the linear scale is evaluated from the wavefront of the zero-order diffracted beam reflected from the linear scale. The linear scale is then tilted to align the axes of the first-order diffracted beams with that of the interferometer so that the X-directional period deviation eX(x,y)of the linear scale can be evaluated from the wavefronts of the X-directional positive and negative first--order diffracted beams. Finally, the Z-directional flatness eZ(x,y) and X-directional period deviation eX(x,y) were verified by comparing those with the nonlinear components of the 2-DOF linear encoder using the evaluated linear scale.

Fabrication of Scale Gratings for Surface Encoders by Using Laser Interference Lithography with 405 nm Laser Diodes

Xinghui Li,Yuki Shimizu,So Ito,Wei Gao 한국정밀공학회 2013 International Journal of Precision Engineering and Vol. No.

This paper presents a cost-effective fabrication method of grating structures with a period of sub-μm for surface encoders. By employing an inexpensive and compact blue laser diode, which has a wavelength of 405 nm and is used in Blu-ray disc drives, a Lloyd’s mirror interferometer has been developed to carry out laser interference lithography for the fabrication of grating structures. Experimental results showed that the developed fabrication system is capable of fabricating grating structures with a pitch of 570 nm. The relative pitch deviation is confirmed to be approximately 1%, which meets the requirement for the scale grating used in a surface encoder. The influence of the limited coherence length of the laser diode on the fabrication area of the grating structures has also been investigated. To expand the fabrication area of the grating structure, a laser source, which has a wavelength of 405 nm and a longer coherence length with a mode selection cavity, is employed in the fabrication system. It has been verified by experiments that the fabrication area of the sub-μm periodic grating structures can be expanded to 300 mm2 with the laser source.

Surface Profile Measurement of Internal Micro-Structures

Bin Xu,Yuki Shimizu,So Ito,Wei Gao 한국정밀공학회 2013 International Journal of Precision Engineering and Vol. No.

A measurement system is presented for surface profile measurements of micro-structures generated on internal cylindrical surfaces of workpieces. The main components of the measurement system are an air-bearing spindle to rotate the measured internal microstructures,an air-bearing displacement sensor with a diamond micro-stylus probe to scan the surface profile of the internal microstructures being measured and a vibration isolation table to reduce the disturbance of the measurement environment. The stability of the air-bearing displacement sensor with a diamond micro-stylus probe was experimentally investigated. Measurements of surface profile of internal micro-structures were also carried out while employing a newly-developed algorithm to correct errors caused by the tip radius of the diamond micro-stylus.

The Shortest Step Algorithm with Network Coding on Multihop Wireless Cyclic Networks

Hiroshi Tamura,Yuki Shimizu,Masakazu Sengoku,Shoji Shinoda 대한전자공학회 2009 ITC-CSCC :International Technical Conference on Ci Vol.2009 No.7

Multihop wireless networks consist of mobile terminals with personal communication devices. Each terminal can receive a message from a terminal and send it to the other terminal. If a terminal can not communicate the other terminal that sends data directly, some terminals relay the data. Network coding is a new architecture for wireless network and various applications using this architecture are expected. In this paper, we evaluate network coding in cyclic networks and we consider relations with a certain problem in the graph theory

A Method for Advanced Analysis of Item Browsing Data Considering User Interest Durations Using Parameters Estimated from Hidden Semi-Markov Model

Kirin Tsuchiya,Yuki Tsuboi,Ryotaro Shimizu,Masayuki Goto 대한산업공학회 2023 Industrial Engineeering & Management Systems Vol.22 No.4

Efficacy and Safety of Abdominal Trunk Muscle Strengthening Using an Innovative Device in Elderly Patients With Chronic Low Back Pain: A Pilot Study

Satoshi Kato,Satoru Demura,Yuki Kurokawa,Naoki Takahashi,Kazuya Shinmura,Noriaki Yokogawa,Noritaka Yonezawa,Takaki Shimizu,Ryo Kitagawa,Hiroyuki Tsuchiya 대한재활의학회 2020 Annals of Rehabilitation Medicine Vol.44 No.3

Objective To examine the efficacy and safety of an innovative, device-driven abdominal trunk muscle strengthening program, with the ability to measure muscle strength, to treat chronic low back pain (LBP) in elderly participants. Methods Seven women with non-specific chronic LBP, lasting at least 3 months, were enrolled and treated with the prescribed exercise regimen. Patients participated in a 12-week device-driven exercise program which included abdominal trunk muscle strengthening and 4 types of stretches for the trunk and lower extremities. Primary outcomes were adverse events associated with the exercise program, improvement in abdominal trunk muscle strength, as measured by the device, and improvement in the numerical rating scale (NRS) scores of LBP with the exercise. Secondary outcomes were improvement in the Roland-Morris Disability Questionnaire (RDQ) score and the results of the locomotive syndrome risk test, including the stand-up and two-step tests. Results There were no reports of increased back pain or new-onset abdominal pain or discomfort during or after the device-driven exercise program. The mean abdominal trunk muscle strength, NRS, RDQ scores, and the stand-up and two-step test scores were significantly improved at the end of the trial compared to baseline. Conclusion No participants experienced adverse events during the 12-week strengthening program, which involved the use of our device and stretching, indicating the program was safe. Further, the program significantly improved various measures of LBP and physical function in elderly participants.

Design of a Laser Autocollimator-based Optical Sensor with a Rangefinder for Error Correction of Precision Slide Guideways

Siew Leng Tan,Yuki Shimizu,Takayuki Meguro,So Ito,Wei Gao 한국정밀공학회 2015 International Journal of Precision Engineering and Vol. No.

This paper presents the design and construction of a laser autocollimator-based optical sensor for measurement of the tilt angles ofa reflector mounted on the guideways or the moving table of a precision linear slide in the production process of the slide, wherethe measurement is repeatedly carried out together with a hand scraping operation for correction of the form errors of the slideguideways. Differing from a conventional autocollimator, a laser rangefinder unit is integrated with the autocollimation unit fordetection of the positions of the reflector, which is necessary for the efficient error correction of the slide guideways. Theautocollimation unit and the rangefinder unit share the same light source for a compact optical design. The optical power of the laserbeam is first set to be constant for tilt angles measurement. Then the optical power is modulated with a frequency of 66.7 MHz formeasuring the position/distance based on the phase shift method. The resolution of the laser autocollimator is confirmed to be 0.2arc-second over a range of ±50 arc-seconds while the measurement positions can be detected with a resolution of 1 mm by therangefinder, which satisfies the requirements from production of the slide.

WHAT DETERMINES ANIME PILGRIMS’ VISIT INTENTION AND DESTINATION LOYALTY?

Akinori Ono,Ryosuke Shimizu,Sumiaki Kawamura,Yasuto Nishimori,Yuki Oguro,Sari Yamamoto 글로벌지식마케팅경영학회 2016 Global Marketing Conference Vol.2016 No.7

Japanese animation, called anime, has long been regarded as a niche culture reserved for ‘nerds’ (otaku) in Japan. The word otaku refers to individuals who spend most of their time alone at home watching anime, reading comics (manga) and/or playing video games. However, in recent years, otaku, or anime viewers, have changed their behavioral patterns, resulting in a new transcultural movement. That peculiar phenomenon is known as anime pilgrimage, which involves traveling to locations that resemble particular scenes in anime pieces, even though the locations themselves may be ordinary places. Research on ordinary tourism has focused mainly on destination attributes as determinants of visit intention/destination loyalty. Research on film tourism places additional emphasis on the role of film involvement. We focus here on social influences. The results of structured regression analyses show that our new models were superior to previous models that omitted investigation of social influences. Furthermore, the results show that though, during the pre-trip period “within home”, anime nerds may expect that they will interact primarily with other nerds, they enjoy interactions with the local people while traveling. Such transcultural experiences result in higher destination loyalty during the post-trip period “beyond home”.

Spindle Error Motion Measurement of a Large Precision Roll Lathe

이정철,Wei Gao,Yuki Shimizu,황주호,오정석,박천홍 한국정밀공학회 2012 International Journal of Precision Engineering and Vol. No.

This paper describes a spindle error motion measurement system to evaluate the performance of the spindle of a large precision roll lathe, which is under development for fabrication of large-scale roll dies of micro-structured surfaces. The measurement system employed a large-scale roll workpiece with a diameter of 320 mm and a length of 1800 mm as a measurement artifact instead of a master object to figure out the spindle error motion over the entire fabrication length. To separate the spindle error motion and the out-of-roundness of the roll workpiece, the reversal method was employed. Two capacitive type displacement probes were mounted on the designed probe holders which were arranged to be faced to each other with the roll workpiece between them. Spindle error motion measurement was conducted at several sections of the roll workpiece along the roll axis to verify the tilt error motion of the spindle as well as the radial error motion. As the rotational speed was different for the mirror finishing fabrication of the roll workpiece and fabrication of the micro-structures on the roll workpiece, the spindle error motion was measured at rotational speeds of 5 and 300 rpm, respectively. Experimental results of the out-of-roundness of the roll workpiece as well as the spindle error motion measurement are presented in this paper.