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排序方式: 共有2178条查询结果,搜索用时 31 毫秒
961.
Noriyasu Homma Yuko Kawai Satoshi Shimoyama Tadashi Ishibashi Makoto Yoshizawa 《Artificial Life and Robotics》2009,14(2):191-194
We have developed several morphological image filters that can be useful for computer-aided medical image diagnosis. Several
computer-aided diagnosis (CAD) systems for lung cancer and breast cancer have been developed to assist the radiologist’s diagnostic
work. The CAD systems for lung cancer can automatically detect pathological changes (pulmonary nodules) with a high true-positive
rate (TP) even under low false-positive rate (FP) conditions. On the other hand, the conventional CAD systems for breast cancer
can automatically detect some pathological changes (calcifications and masses), but the TP for other changes, such as architectural
distortion, is still very low. Motivated by the radiologist’s cognitive processes to increase TP for breast cancer, we propose
new methods to extract novel morphological features from X-ray mammography. Simulation results demonstrate the effectiveness
of the morphological methods for detecting tumor shadows. 相似文献
962.
In this paper, we detect “innovative topics”, those that are new and hopefully interesting to the user. We try to expand user interests significantly by letting the user browse those topics.We first generate user-interest ontologies that allow user profiles to be constructed as a hierarchy of classes where a user interest weight is assigned to each class and instance. Next, we measure the similarity between user interests by using interest weights on their user-interest ontologies and generate user group GU that has high similarity to user u. The innovative topics for u are then detected by determining a suitable size of GU and analyzing the ontologies in GU. 相似文献
963.
Yadong Liu Wei Li Kazuo Yamazaki Keizo Kashihara Makoto Fujishima 《Journal of Intelligent Manufacturing》2008,19(2):241-248
In this paper, an event-driven simulation method is proposed for the motor driver in a virtual machine tool system (VMT),
of which simulation speed is always a puzzle. This method utilizes a set of pre-defined events to trigger the execution of
simulator in a non-deterministic manner and at the most efficient moment. Comparing to the conventional time domain simulation
method, it dramatically reduces the CPU time consumption without losing simulation accuracy, therefore it improves the simulation
efficiency. The effectiveness of this method is verified through a PMSM (Permanent Magnet Synchronous Motor) motor driver
model in studying Servo/Mechanical interaction within a VMT. 相似文献
964.
Chihiro Yamamoto Xinyi He Takayoshi Katase Keisuke Ide Yosuke Goto Yoshikazu Mizuguchi Akane Samizo Makoto Minohara Shigenori Ueda Hidenori Hiramatsu Hideo Hosono Toshio Kamiya 《Advanced functional materials》2021,31(8):2008092
Tin mono-selenide (SnSe) is one of the most promising thermoelectric materials; however, it experiences difficulty in controlling the carrier polarity, which is inevitable for realizing p-n homojunction devices. Herein, double switching of charge polarity in (Sn1−xSbx)Se by varying x is reported; pure SnSe shows p-type conduction, whereas the polarity of (Sn1−xSbx)Se switches to n-type conduction for 0.005 < x < 0.05, and then re-switches to p-type conduction for x > 0.05. The major Sb substitution site switches from the Se (SbSe) to Sn site (SbSn) with increasing x. SbSn (Sb3+ at Sn2+) works as a donor, but SbSe (Sb3− at Se2−) does not produce a hole because of the Sb–Sb dimer formation. The mechanism of double polarity switching is explained by native p-type conduction in pure SnSe due to Sn-vacancy formation, whereas (Sn1−xSbx)Se exhibits n-type behavior due to conduction through the SbSe impurity band formed above the valence band maximum, and finally re-switches to weak p-type, where the Fermi level approaches the midgap level between the SbSe band and conduction band minimum. Clarification of the Sb doping mechanism will provide a crucial guide for developing more sophisticated doping routes for SnSe and high-performance energy-related devices. 相似文献
965.
Hirokazu Seto Atsushi Saiki Ryosuke Matsushita Wataru Mitsukami Seiji Kamba Makoto Hasegawa Yoshiko Miura Yumiko Hirohashi Hiroyuki Shinto 《Advanced Powder Technology》2021,32(6):1920-1926
A microparticle counter based on a metal mesh device was developed. The metal mesh device had a lattice-shaped structure with well-regulated holes of 1.8 μm. The collection percentages of differently sized microparticles using the metal mesh device were determined by flow cytometry. The cut-off point and hole size of the metal mesh device were identical. Polystyrene microparticles were detected from changes in the spectroscopic properties of the metal mesh device. When microparticles were trapped on the holes of the metal mesh device, the transmittance in the infrared spectra decreased. Microparticles smaller than the holes were not detected by the metal mesh device, whereas 2 and 3 μm microparticles were detected. Polystyrene and silica microparticles could be counted using the metal mesh device via calibration curves between the concentration of microparticles and the change level in the transmittance of the metal mesh device. The separation of microparticles from a mixture suspension using the metal mesh device was evaluated. Unlike a microfiber filter, only 2 μm microparticles were collected from coexisting 1 μm microparticles by the metal mesh device. Owing to its high separation ability, the metal mesh device selectively detected 2 μm microparticles in coexisting 10-equivalence 1 μm microparticles. 相似文献
966.
High‐resolution OLED display with remarkably low power consumption using blue/yellow tandem structure and RGBY subpixels 下载免费PDF全文
Ryohei Yamaoka Toshiki Sasaki Riho Kataishi Noriko Miyairi Koji Kusunoki Makoto Kaneyasu Hiroyuki Miyake Nobuharu Ohsawa Satoshi Seo Yoshiharu Hirakata Shunpei Yamazaki Koji Ono Takayuki Cho Hidenori Mori 《Journal of the Society for Information Display》2015,23(10):451-456
A top‐emission organic light‐emitting diode (OLED) with a microcavity structure combined with a blue/yellow tandem structure was developed. A high‐resolution active‐matrix OLED display with the world's lowest level of power consumption using the tandem OLED with red, green, blue, and yellow subpixels was fabricated. 相似文献
967.
This paper presents a new combinatorial auction protocol that is robust against false-name bids. Internet auctions have become an integral part of Electronic Commerce (EC) and a promising field for applying agent and Artificial Intelligence technologies. Although the Internet provides an excellent infrastructure for combinatorial auctions, we must consider the possibility of a new type of cheating, i.e., an agent tries to profit from submitting several bids under fictitious names (false-name bids). If there exists no false-name bid, the Generalized Vickrey Auction protocol (GVA) satisfies individual rationality, Pareto efficiency, and incentive compatibility. On the other hand, when false-name bids are possible, it is theoretically impossible for a combinatorial auction protocol to simultaneously satisfy these three properties.
Our newly developed Leveled Division Set (LDS) protocol, which is a modification of the GVA, utilizes reservation prices of auctioned goods for making decisions on whether to sell goods in a bundle or separately. The LDS protocol satisfies individual rationality and incentive compatibility even if agents can submit false-name bids, although it is not guaranteed to achieve a Pareto efficient social surplus. Simulation results show that the LDS protocol can achieve a better social surplus than that for a protocol that always sells goods in one bundle. 相似文献
968.
The aberration of a multipole Wien filter for energy-filtered x-ray photoemission electron microscopy was analyzed and the optimized Fourier components of the electric and magnetic fields for the third-order aperture aberration corrections were obtained. It was found that the third-order aperture aberration correction requires 12 electrodes and magnetic poles. 相似文献
969.
Two deoxyuridine derivatives each bearing a monophosphate group at the 5-position with a C3 linker, were incorporated into an oligonucleotide. By using this modified oligonucleotide, a bulge was formed at a predetermined position in a DNA substrate, and two monophosphate groups were placed at both junctions of the bulge. Upon treatment of the mixture with Ce(IV)-EDTA at pH 7.0, the phosphodiester linkages at the bulge site were selectively and efficiently hydrolyzed. The monophosphate groups introduced into the bulge site greatly accelerated site-selective DNA scission. Compared with the previously reported two-additive system, which combines two oligonucleotide additives each with a monophosphate at their termini, the present one-additive system is simpler and more convenient. Furthermore, site-selective DNA hydrolysis by using this one-additive system is successful even at high reaction temperatures (e.g., 55 degrees C). This reflects the thermodynamic stability of the duplexes formed between the substrate and the additive DNA. 相似文献
970.
The discovery of non-linear causal relationship under additive non-Gaussian noise models has attracted considerable attention recently because of their high flexibility. In this paper, we propose a novel causal inference algorithm called least-squares independence regression (LSIR). LSIR learns the additive noise model through the minimization of an estimator of the squared-loss mutual information between inputs and residuals. A notable advantage of LSIR is that tuning parameters such as the kernel width and the regularization parameter can be naturally optimized by cross-validation, allowing us to avoid overfitting in a data-dependent fashion. Through experiments with real-world datasets, we show that LSIR compares favorably with a state-of-the-art causal inference method. 相似文献