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991.
Tomoyoshi Shimobaba Jiantong Weng Takahiro Sakurai Naohisa Okada Takashi Nishitsuji Naoki Takada Atsushi Shiraki Nobuyuki Masuda Tomoyoshi Ito 《Computer Physics Communications》2012,183(5):1124-1138
Diffraction calculations, such as the angular spectrum method and Fresnel diffractions, are used for calculating scalar light propagation. The calculations are used in wide-ranging optics fields: for example, Computer Generated Holograms (CGHs), digital holography, diffractive optical elements, microscopy, image encryption and decryption, three-dimensional analysis for optical devices and so on. However, increasing demands made by large-scale diffraction calculations have rendered the computational power of recent computers insufficient. We have already developed a numerical library for diffraction calculations using a Graphic Processing Unit (GPU), which was named the GWO library. However, this GWO library is not user-friendly, since it is based on C language and was also run only on a GPU. In this paper, we develop a new C++ class library for diffraction and CGH calculations, which is referred to as a CWO++ library, running on a CPU and GPU. We also describe the structure, performance, and usage examples of the CWO++ library.Program summaryProgram title: CWO++Catalogue identifier: AELL_v1_0Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AELL_v1_0.htmlProgram obtainable from: CPC Program Library, Queen?s University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 109 809No. of bytes in distributed program, including test data, etc.: 4 181 911Distribution format: tar.gzProgramming language: C++Computer: General computers and general computers with NVIDIA GPUsOperating system: Windows XP, Vista, 7Has the code been vectorized or parallelized?: Yes. 1 core processor used in CPU and many cores in GPU.RAM: 256 M bytesClassification: 18External routines: CImg, FFTWNature of problem: The CWO++ library provides diffraction calculations which are useful for Computer Generated Holograms (CGHs), digital holography, diffractive optical elements, microscopy, image encryption and decryption and three-dimensional analysis for optical devices.Solution method: FFT-based diffraction calculations, computer generated holograms by direct integration.Running time: The sample runs provided take approximately 5 minutes for the C++ version and 5 seconds for the C++ with GPUs version. 相似文献
992.
Abdallah Farrage Naoki Uchiyama 《The International Journal of Advanced Manufacturing Technology》2018,99(5-8):1203-1214
Friction occurring in all mechanical systems, such as computer numerical controlled (CNC) machine tools, is an important issue in achieving the high accurate performance. Friction adversely affects not only motion accuracy of drive axes but also excessively consumes energy. Feed drives of CNC machines normally operate all day and night around the world, and therefore consumed energy reduction is highly expected. The motivation behind this work is to construct a novel friction model that can comprise many unknown friction sources in both low and high velocity regions and enable a friction compensator to precisely describe actual frictional behavior. A sliding mode control (SMC) is designed to verify the effectives of the proposed friction model in a biaxial feed drive system. Experimental results confirm that a combination of SMC and the proposed friction can effectively improve tracking accuracy and further achieve significant reduction of consumed energy compared to combining with the conventional model. Results show that the proposed approach can largely decrease the mean tracking error to less than 5 µm for each axis. The new friction also achieved effective reduction of control variance by 7.62%. Consequently, consumed energy of feed drives was significantly improved by 12.83% compared to using the conventional model. 相似文献
993.
A microlateral force sensor (MLFS) was developed and evaluated using atomic force microscopy (AFM). The sensor was attached to a sensing table supported by a suspension system. The lateral motion of the sensing table was activated by a comb actuator. The driving voltage to the comb actuator was controlled to maintain a constant position of the sensing table by detecting the tunneling current at a detector, which consisted of two electrodes where the bias voltage was applied. An AFM was used to apply a lateral force to the sensing table of the sensor. When the probe of a cantilever was pressed against the sensing table and a raster scanning was conducted, the driving voltage of the comb actuator changed to compensate the friction force between the probe and sensing table. AFM measurements of an asperity array on the sensing table were conducted, and a lateral force microscopy image (LFM) was obtained from the change in driving voltage. The image by MLFS was very similar to the LFM image that was conventionally obtained from torsion of the cantilever. The LFM image strongly correlated with the gradient image calculated from the AFM topographic image. The force sensitivity of the MLFS was determined by comparing the LFM image obtained by using the MLFS with the tangential force derived from the gradient of the AFM image. 相似文献
994.
Specific Spatial Localization of Actin and DNA in a Water/Water Microdroplet: Self‐Emergence of a Cell‐Like Structure
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Naoki Nakatani Hiroki Sakuta Dr. Masahito Hayashi Shunsuke Tanaka Dr. Kingo Takiguchi Dr. Kanta Tsumoto Prof. Dr. Kenichi Yoshikawa 《Chembiochem : a European journal of chemical biology》2018,19(13):1370-1374
The effect of binary hydrophilic polymers on a pair of representative bio‐macromolecules in a living cell has been examined. The results showed that these bio‐macromolecules exhibited specific localization in cell‐sized droplets that were spontaneously formed through water/water microphase segregation under crowding conditions with coexisting polymers. In these experiments, a simple binary polymer system with poly(ethylene glycol) (PEG) and dextran (DEX) was used. Under the conditions of microphase segregation, DNA was entrapped within cell‐sized droplets rich in DEX. Similarly, F‐actin, linearly polymerized actin, was entrapped specifically within microdroplets rich in DEX, whereas G‐actin, a monomeric actin, was distributed evenly inside and outside these droplets. This study has been extended to a system with both F‐actin and DNA, and it was found that DNA molecules were localized separately from aligned F‐actin proteins to create microdomains inside microdroplets, reflecting the self‐emergence of a cellular morphology similar to a stage of cell division. 相似文献
995.
Dr. Kazuhisa Yanagi Naoki Kobayashi Kazufumi Kasahara 《International Journal of Machine Tools and Manufacture》1995,35(2)
This paper deals with surface waviness assessment by a commercial three-dimensional stylus instrument. To measure macroscopic waviness curve on an engineering surface, it was proposed to use a round stylus tip of relatively large radius. Developed in this paper, is a method to obtain the appropriate stylus tip radius in accordance with the sample surface texture and the corresponding discrete spacing for lattice data sampling. On condition that any two adjacent height data points are well-correlated, the statistical mean height and the overall deviation of the 3-D undulation summit height are also presented for a functional evaluation of waviness curves or envelope surface. 相似文献
996.
Role of nerve growth factor in the olfactory system 总被引:1,自引:0,他引:1
Miwa T Moriizumi T Horikawa I Uramoto N Ishimaru T Nishimura T Furukawa M 《Microscopy research and technique》2002,58(3):197-203
Olfactory neurons are unique in the mammalian nervous system because of their capacity to regenerate in adult animals. It has been shown that olfactory receptor cells located in the olfactory epithelium are replaced on a continuous basis and in response to injury throughout the life span of most species. NGF, which is one of the neurotrophic factors, is present in many areas of the central and peripheral nervous system. It has been shown that NGF in the olfactory bulb plays a role in the survival of cholinergic neurons in the horizontal limb of the diagonal band (HDB). Recent studies of NGF in the olfactory bulb suggest that it is involved in the development, maintenance, and regeneration of olfactory receptor cells. In this study, we review reports examining the relationship between NGF in the olfactory bulb and neuronal regeneration and development in the mammalian olfactory systems. Low- and high-affinity NGF receptor immunoreactivity is markedly expressed during regeneration and at different stages of development in the mouse olfactory system. This level of immunoreactivity is no longer present after completion of regeneration and at maturation. Other findings indicate that NGF injected into the olfactory bulb is transported retrogradely to the olfactory epithelium. It has also been shown that continuous anti-NGF antibody injection into the olfactory bulb causes degeneration and olfactory dysfunction. Administration of NGF directory into nasal cavity results in an increase in the expression of olfactory marker protein within the olfactory epithelium in axotomized rats. These findings suggested that the presence of NGF in the olfactory bulb plays an essential role in regeneration, maintenance, and development in the olfactory system of mammals. 相似文献
997.
Hua Yang Naoki Wakamiya Masayuki Murata Takanori Iwai Satoru Yamano 《Wireless Networks》2017,23(7):2093-2110
The 5th generation mobile and wireless communication systems are expected to accommodate exploding traffic, increasing number of devices, and heterogeneous applications driven by proliferation of IoT and M2M technologies. However, the centralized mobility management architecture in a current mobile core network would face critical problems such as excessive concentration of load on specific servers and considerable increase in C-plane overhead. To solve the problems we first consider a novel architecture of distributed mobility management in C-plane in the mobile core network, which employs virtualized mobility management entity called ADMMEs (Autonomous Distributed Mobility Management Entity) in this paper. In addition, to assign an appropriate ADMME to a UE in accordance with mobility characteristics of the UE and a management policy, we propose an autonomous and adaptive ADMME selection scheme. We adopt a biologically-inspired algorithm, called attractor selection, to accomplish adaptive selection taking into account multiple objectives. Through simulation experiments, we confirmed our proposal could accomplish more than 63 % performance improvement comparing to the current method from viewpoints of delay, load balancing, and C-plane overhead under a dynamic mobility scenario. 相似文献
998.
Vikram Bhatia Steven J. Gregorski Dragan Pikula Satish C. Chaparala David A. S. Loeber Jacques Gollier Joan D. Gregorski Martin Hempstead Yukihiro Ozeki Yoshiaki Hata Kazuhiro Shibatani Fumio Nagai Nobuyoshi Mori Yukinobu Nakabayashi Naoki Mitsugi Satoshi Nakano 《Journal of the Society for Information Display》2009,17(3):271-277
Abstract— Efficient and compact green lasers are keystone components for micro‐projector applications in mobile devices. An architecture that consists of an infrared‐producing DBR (distributed Bragg reflector) laser with a frequency‐doubling crystal is used to synthesize a green laser that has high electrical‐to‐optical conversion efficiency and can be modulated at speeds required for scanner‐based projectors. The design and performance of a green‐laser package that uses adaptive optics to overcome the challenge of maintaining alignment between the waveguides of the DBR laser and the frequency‐doubling crystal over temperature and lifetime is described. The adaptive optics technology that is employed uses the piezo‐based smooth impact drive mechanism (SIDM) actuators that offer a very small step size and a range of travel adequate for the alignment operation. The laser is shown to be compact (0.7 cm3 in volume) and capable of a wall‐plug efficiency approaching 10% (at 100‐mW green power). It was demonstrated that the adaptive optics enables operation over a wide temperature range (10–60°C) and provides the capability for low‐cost assembly of the device. 相似文献
999.
Keisuke Yoneda Toshiki Iida TaeHyon Kim Ryo Yanase Mohammad Aldibaja Naoki Suganuma 《Artificial Life and Robotics》2018,23(4):474-480
The automated driving is an emerging technology in which a car performs recognition, decision making, and control. The decision-making system consists of route planning and trajectory planning. The route planning optimizes the shortest path to the destination like an automotive navigation system. According to static and dynamic obstacles around the vehicle, the trajectory planning generates lateral and longitudinal profiles for vehicle maneuver to drive the given path. This study is focused on the trajectory planning for vehicle maneuver in urban traffic scenes. This paper proposes a trajectory generation method that extends the existing method to generate more natural behavior with small acceleration and deceleration. This paper introduces an intermediate behavior to gradually switch from the velocity keeping to the distance keeping. The proposed method can generate smooth trajectory with small acceleration/deceleration. Numerical experiments show that the vehicle generates smooth behaviors according to surrounding vehicles. 相似文献
1000.
Gwendoline M. Toh Naoki Yanagisawa Robert C. Corcoran Debashis Dutta 《Microfluidics and nanofluidics》2010,9(6):1135-1141
In this article, we report a novel approach to fabricating a low molecular weight cut-off membrane that could readily be employed
for several microfluidic applications. The reported structure was created by selectively retaining a precursor solution [5%
(w/v) maleic anhydride, 21% (v/v) (37:1) acrylamide/bisacrylamide, and 0.2% (w/v) VA-086 photoinitiator] in a chosen location
of a microfluidic network via capillary forces and then photo-polymerizing the mixture. The pores in the resulting membrane
were subsequently filled with 3-aminopropyltriethoxysilane, heated, and then treated with sodium silicate solution and heated
again, giving a structure having reduced porosity. The composite membrane thus created has been shown to have a molecular
weight cut-off that is at least an order of magnitude smaller than other photo-polymerized microfluidic membranes reported
in the literature. Moreover, this polymer–silicate structure was observed to be capable of blocking electroosmotic flow, thereby
generating a pressure gradient around its interface with an open microchannel upon application of an electric field across
the microchannel-membrane junction. In this study, a fraction of the resulting hydrodynamic flow was successfully guided to
an electric field free analysis channel to implement a pressure-driven assay. With our current design pressure-driven velocities,
up to 1.8 mm/s was generated in the electric field free analysis channel for an applied voltage of 2 kV in the pumping section.
Finally, the functionality of this integrated microfluidic device was demonstrated by implementing a reverse phase chromatographic
separation using the pressure-driven flow generated on-chip. 相似文献