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101.
Shinya Yamamura Akira Nagata Masato Tsuru Hitomi Tamura 《Simulation Modelling Practice and Theory》2011,19(1):30-46
We have proposed the concept of the virtual segment (VS), in which a global communication service is provided by combining a store–carry–forward scheme using vehicles with broadband wireless/wired network infrastructures along roads connected to the Internet. The VS can be a practical framework for non-real-time, asynchronous message transfer (especially for large messages) in a cost-effective manner. In this study, a critical implementation design issue, the message forward scheduling, in the VS approach is discussed and investigated through computer simulation by our developed VS simulator that has reflected the results of the field experiment for realistic performance evaluation. 相似文献
102.
Akira Inoue 《国际自动化与计算杂志》2010,7(2):213-218
In this paper, robust stability of nonlinear plants represented by non-symmetric Prandtl-Ishlinskii (PI) hysteresis model is studied. In general, PI hysteresis model is the weighted superposition of play or stop hysteresis operators, and the slopes of the operators are considered to be the same. In order to make a hysteresis model, a modified form of non-symmetric play hysteresis operator with unknown slopes is given. The hysteresis model is described by a generalized Lipschitz operator term and a bounded parasitic term. Since the generalized Lipschitz operator is unknown, a new condition using robust right coprime factorization is proposed to guarantee robust stability of the controlled plant with the hysteresis nonlinearity. As a result, based on the proposed robust condition, a stabilized plant is obtained. A numerical example is presented to validate the effectiveness of the proposed method. 相似文献
103.
Kikuta K Tochigi N Saito S Shimoda T Morioka H Toyama Y Hosono A Suehara Y Beppu Y Kawai A Hirohashi S Kondo T 《Proteomics. Clinical applications》2010,4(5):560-567
Purpose : We aimed to identify novel chemotherapy responsiveness biomarkers for osteosarcoma (OS) by investigating the global protein expression profile of 12 biopsy samples from OS patients. Experimental design : Six patients were classified as good responders and six as poor responders, according to the Huvos grading system. The protein expression profiles obtained by 2‐D DIGE consisted of 2250 protein spots. Results : Among them, we identified 55 protein spots whose intensity was significantly different (Bonferroni adjusted p‐value<0.01) between the two patient groups. Mass spectrometric protein identification demonstrated that the 55 spots corresponded to 38 distinct gene products including peroxiredoxin 2 (PRDX 2). Use of a specific antibody against PRDX 2 confirmed the differential expression of PRDX 2 between good and poor responders, while PRDX 2 levels as measured by Western blotting correlated highly with their corresponding 2‐D DIGE values. The predictive value of PRDX 2 expression was further confirmed by examining an additional four OS cases using Western blotting. Conclusions and clinical relevance : These results establish PRDX 2 as a candidate for chemotherapy responsiveness marker in OS. Measuring PRDX 2 in biopsy samples before treatment may contribute to more effective management of OS. 相似文献
104.
One of the biggest problems in applying stereo vision techniques in field robotics is how to acquire 3D terrain maps under extreme light conditions. Through multiple exposures, the dynamic range of images can be increased. In this paper, instead of using existing lighting enhancement methods such as exposure fusion to increase the texture of 2D image, we propose that the matching costs of the images grabbed with multiple exposures are directly summed by weight. Compared with the previous methods such as exposure fusion, with the proposed method, it is not necessary to fuse the 2D images captured with multiple exposures, and for each pixel of the matching image, the local information in its local window can be better retained. Since it is possible that the camera is moved between exposures when the images are grabbed, the images captured with multiple exposures are aligned to the image acquired with auto exposure. In order to evaluate the performance of the proposed method, two different stereo matching algorithms were used: a local window-based method and semi-global method. Through experiments in laboratory and outdoors with a stereo vision camera fixed on a tripod and held in the hand, it was verified that the proposed method consistently allowed more valid points to be obtained and the 3D model of terrain can be built more accurately. Especially when the local window-based method was used, the proposed method performed much better. 相似文献
105.
Single‐layered retardation films with negative wavelength dispersion birefringence made from liquid‐crystalline monomers 下载免费PDF全文
Mika Yamamoto Koichi Endo Yasuhiro Kuwana Isa Nishiyama 《Journal of the Society for Information Display》2017,25(7):405-410
Organic light‐emitting diode displays have a cathode composed of a layer of highly reflective metal. Reflection of external light from this layer can be suppressed with a broadband quarter‐wave plate. Although various types of quarter‐wave plate retardation films have been prepared by copolymerizing, mixing, or laminating multiple polymers, ideal wavelength dispersion has not been achieved with thin retardation films because of their relatively low birefringence and the complexity of the procedure required manufacturing them. In this study, we developed (i) new liquid‐crystalline monomers with negative wavelength dispersion birefringence that we used to obtain thin, single‐layered retardation films suitable for coating and (ii) retardation films with different molecular alignments. We found that the monomers showed high solubility and high regularity of molecular alignment, with less damage to the substrate and alignment films. We also investigated the wavelength dispersion and thermal stability of the films. We succeeded in developing retardation films that had a homeotropic alignment or a hybrid alignment with negative wavelength dispersion. These alignments can be used to obtain antireflection films with an improved viewing angle for organic light‐emitting diode displays or next‐generation thin displays. 相似文献
106.
To examine gender differences in hand stability, finger position and force holding tasks at low force levels were conducted with 30 male and 30 female young adults. Total fluctuation was defined as the standard deviation of measured data and fluctuation and the 10-Hz component of the physiological tremor were compared between maleand female subjects. In all tasks, the total fluctuation and the 10-Hz tremor were significantly larger in male subjects than females. On average, the fluctuation was 1.3 times larger and the 10-Hz tremor was 1.6 times larger. The results of this study suggest that women have superior hand stability compared with men at low force levels. Finger length, maximal voluntary contraction and surface electromyography were also measured and factors related to gender differences in hand stability are discussed. STATEMENT OF RELEVANCE: Hand stability is crucial for precise manual operations. This study demonstrated gender differences in hand steadiness at low force levels. Though hand dexterity cannot be explained only by hand stability, the results of this study are useful not only for occupational aptitude tests but also for neuropsychological tests. 相似文献
107.
Akira Masutani Tony Roberts Bettina Schüller Nadine Hollfelder Pinar Kilickiran Akira Sakaigawa Gabriele Nelles Akio Yasuda 《Journal of the Society for Information Display》2008,16(1):137-141
Abstract— A polymer‐dispersed liquid‐crystal (PDLC) matrix template embedded with nano/microparticles can be backfilled/infiltrated with a dye‐doped liquid crystal for a paper‐like reflective display. In this way, a desirable degree of diffusion can be realized to reduce the viewing‐angle dependency of a gain reflector and metallic glare without changing other electro‐optical properties. 相似文献
108.
In this paper, a decentralized proportional-derivative (PD) controller design for non-uniform motion of a Hamiltonian hybrid system is considered. A Hamiltonian hybrid system with the capability of producing a non-uniform motion is developed. The structural properties of the system are investigated by means of the theory of Hamiltonian systems. A relationship between the parameters of the system and the parameters of the proposed decentralized PD controller is shown to ensure local stability and tracking performance. Simulation results are included to show the obtained non-uniform motion. 相似文献
109.
An obstacle avoidance scheme of a two-wheeled mobile robot is shown by selecting an appropriate Lya- punov function. When considering the obstacle, the Lyapunov function may have some local minima. A method which erases the local minima is proposed by using a function which covers the minima with a plane surface. The effectiveness of the proposed method is verified by numerical simulations. 相似文献
110.
Yasuo Kinouchi Shoji Inabayashi Akira Satou Fumitoshi Shouji S. Inabayashi 《Artificial Life and Robotics》2000,4(2):53-56
To construct a “thinking-like” processing system, a new architecture of an adaptive associative memory system is proposed.
This memory system treats “images” as basic units of information, and adapts to the environment of the external world by means
of autonomous reactions between the images. The images do not have to be clear, distinct symbols or patterns; they can be
ambiguous, indistinct symbols or patterns as well. This memory system is a kind of neural network made up of nodes and links
called a localist spreading activation network. Each node holds one image in a localist manner. Images in high-activity nodes
interact autonomously and generate new images and links. By this reaction between images, various forms of images are generated
automatically under constraints of links with adjacent nodes. In this system, three simple image reaction operations are defined.
Each operation generates a new image by combining pseudofigures or features and links of two images.
This work was presented, in part, at the Fourth International Symposium on Artificial Life and Robotics, Oita, Japan, January
19–22, 1999 相似文献