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排序方式: 共有178条查询结果,搜索用时 11 毫秒
41.
Omachi S. Inoue M. Aso H. 《IEEE transactions on pattern analysis and machine intelligence》2001,23(3):315-322
Decorated characters are widely used in various documents. Practical optical character reader is required to deal with not only common fonts but also complex designed fonts. However, since the appearances of decorated characters are complicated, most general character recognition systems cannot give good performances on decorated characters. In this paper, an algorithm that can extract character's essential structure from a decorated character is proposed. This algorithm is applied in preprocessing of character recognition. The proposed algorithm consists of three procedures: global structure extraction, interpolation of structure and smoothing. By using multiscale images, topographical features, such as ridges and ravines are detected for structure extraction. Ridges are used for extracting global structure and ravines are used for interpolation. Experimental results show character structures can be clearly extracted from very complex decorated characters 相似文献
42.
Shield Tunnel Construction in Centrifuge 总被引:3,自引:0,他引:3
Toshi Nomoto Shinichiro Imamura Toshiyuki Hagiwara Osamu Kusakabe Nariaki Fujii 《Canadian Metallurgical Quarterly》1999,125(4):289-300
A large number of centrifuge model tests for simulating the shield construction process in dry sand was carried out by using a newly developed 100 mm diameter miniature shield tunnel. Different construction processes were modeled by three series of tests. A “buried tube test” was conducted to measure the lining stress under a centrifugal acceleration, a “tail void test” simulated the process of tail void formation only, and a “shield test” dealt with the complete process of shield construction. Lining stresses, transverse and longitudinal surface settlements, and earth pressures around the tunnel were simultaneously measured during advancement of the shield at a centrifugal acceleration of 25g. The lining stress at the crown elevation was well predicted by Terzaghi's loosening earth pressure. From the comparison with the recent field measurements and the comparative results of three series of tests, it was confirmed that the shield construction process was successfully simulated in a centrifuge. An experimental formula for estimating the surface settlement above the shield was deduced by a function of tail void thickness and cover-to-diameter ratio. 相似文献
43.
Inoue S Tokita S Nishoji T Masuno S Otani K Hashida M Sakabe S 《The Review of scientific instruments》2010,81(12):123302
A simple technique for single-shot microscopic electron imaging was demonstrated for the study of intense femtosecond laser-produced plasmas. Passed through a permanent magnet lens designed for 110-keV electrons, hot electrons emitted from the plasma produced by a single laser pulse of 0.8 mJ with intensity of 3 × 10(16) W/cm(2) were successfully imaged. Analyzing this image, we found that electrons were emitted from an area of 3 μm in diameter. At higher laser intensity of 10(18) W/cm(2), distinct structures were observed in and near the focal spot of the laser; that is, the electrons were emitted from several separate spots. These results show that laser-plasma electron imaging is promising for studying the interactions of femtosecond lasers with high-density plasmas. 相似文献
44.
Daiki Nakamura Masayuki Murata Yasuhiro Hasegawa Takashi Komine Daisuke Uematsu Shinichiro Nakamura Takashi Taguchi 《Journal of Electronic Materials》2010,39(9):1960-1965
An individual bismuth nanowire sample, 593 nm in diameter and 1.64 mm in length, has been successfully grown using a quartz
template. The resistivity and the Seebeck coefficient of the nanowire at 300 K were 1.35 μΩ m and −59 μV/K, respectively, similar to those of a bismuth bulk sample. The temperature dependence of the resistivity was found to decrease
with temperature from 300 K to 175 K and then increase with further temperature reduction below 175 K. The absolute value
of the Seebeck coefficient decreased with temperature from 300 K to 90 K, and the sign of the Seebeck coefficient changed
from negative to positive near 90 K. This result indicated that there was a small amount of contamination in the bismuth.
The carrier density was estimated from the resistivity and Seebeck coefficient on the basis of limitation of the mean free
path and a two-carrier model, and the observed temperature dependences are discussed. 相似文献
45.
Takuya Honma Ikue Sasaki Nobuhiro Tamura Junichi Tatami Shinichiro Fujichika Katsutoshi Komeya Takeshi Meguro 《International Journal of Applied Ceramic Technology》2014,11(2):294-302
In industrial high‐intensity discharge lamps, cracks and delaminations occasionally develop at the interface between SiO2 and the Mo foil in the seal. Here, functionally graded SiO2‐Mo materials for use in these lamps were fabricated by uniaxial compression casting and pressureless sintering. Consequently, vertical cracks developed across the sintered body layers, and interfacial cracks developed between the 100 wt% SiO2 and 90 wt% SiO2‐Mo layers. Therefore, the effects of residual stress, difference in the coefficient of thermal expansion (CTE), and difference in the volume shrinkage on these cracks were investigated. Vertical cracks were suppressed when residual stress was relaxed by annealing near the annealing point of silica glass during the cooling step in the sintering process. Interfacial cracks were suppressed when the difference in the CTE of the interface between the 100 wt% SiO2 and 90 wt% SiO2‐Mo layers was relaxed by inserting layers of 95 wt% SiO2‐Mo between them. Furthermore, the suppression effect became stronger when the difference in the volume shrinkage of the layers was relaxed by sintering to join the separately sintered monolayers. Thus, the development of these cracks was influenced by the residual stress, CTE, and volume shrinkage. Therefore, these cracks can be prevented by optimizing these factors. 相似文献
46.
An ultrasensitive and nonlabeled detection method of nonfluorescent molecules on a microchip was developed by realizing a thermal lens microscope (TLM) with a 266-nm UV pulsed laser as an excitation light source (UV-TLM). Pulsed laser sources have advantages over continuous-wave laser sources in more compact size and better wavelength tuning, which are important for microchip-based analytical systems. Their disadvantage is difficulty in applying a lock-in amplifier due to the high (>10(4)) duty ratio of pulse oscillation. To overcome this problem, we realized a quasi-continuous-wave excitation by modulating the pulse trains at approximately 1 kHz and detecting the synchronous signal with a lock-in amplifier. The optimum pulse repetition frequency was obtained at 80 kHz, which was reasonable considering thermal equilibrium time. Furthermore, a permissible flow velocity in the range of 6.6-19.8 mm/s was found to avoid sensitivity decrease due to photochemical reactions and thermal energy dissipation. Under these conditions, we detected adenine aqueous solutions on a fused-silica microchip without labeling and obtained a sensitivity that was 350 times higher than that in a spectrophotometric method. The sensitivity was enough for detection on a microchip with an optical path length that was 2-3 orders shorter than that in conventional cuvettes. Finally, the UV-TLM method was applied to liquid chromatography detection. Fluorene and pyrene were separated in a microcolumn and detected in a capillary (50-microm inner diameter) with 150 times higher sensitivity than a spectrophotometric method. Our method provides highly sensitive and widely applicable detections for various analytical procedures and chemical syntheses on microchips. 相似文献
47.
Yasuhiro Hasegawa Masayuki Murata Daiki Nakamura Takashi Komine Takashi Taguchi Shinichiro Nakamura 《Journal of Electronic Materials》2009,38(7):944-949
A quartz template having a length of several millimeters and with holes having diameters on the order of micro/nanometers
was fabricated. Bismuth was injected into the template holes by high-pressure injection. A bismuth micro/nanowire array sample
was prepared, and the temperature dependence of the Seebeck coefficient and the resistance were measured in the temperature
range of 50 K to 300 K. Although the temperature dependence of the Seebeck coefficient is similar to that of polycrystalline
bulk bismuth, the temperature coefficient of the resistance is much less than that of the bulk sample. The magnetic-field
dependence of the Seebeck coefficient was also measured. The Umkehr effect was observed, demonstrating that the mixed micro/nanowires
are a bundle of single-crystal wires. The magnitude of the absolute value of the Seebeck coefficient was found to be large
in high magnetic field and at low temperature. 相似文献
48.
Suzuki T Ito M Ezure T Kobayashi S Shikata M Tanimizu K Nishimura O 《Journal of Bioscience and Bioengineering》2006,102(1):69-71
We constructed a pTD1 vector for an insect cell-free translation system containing a 5' untranslated region (UTR) of a polyhedrin gene as a translational enhancer sequence. Its translational efficiency was about 50-fold higher than those of mRNAs without an enhancer sequence. Moreover, the pTD1 vector functioned as an effective expression vector not only in the insect cell-free translation system but also in wheat germ extract and rabbit reticulocyte lysate systems. 相似文献
49.
A system utilizing computer simulations was developed in order to compare (1) situations wherein critically wounded individuals are, at first, ranked and classified into subgroups based on criticalness of the wounds, and then be evaluated and re-ordered within the subgroups before transported to hospitals, with (2) those situations in which the conventional method of transport was employed. The objective of the study is to infer whether there is a further possibility for enhancing the possibility of the wounded individual's survival rate at the time of arrival at the hospital. The variables that are required to be entered include the number of patient subgroups, the number of patients in each of the subgroups, the total number of patients to be transported, the time required to assess the severity of each patient, the speed of the ambulance, the interval between the ambulances' arrivals and departures, and the distance between the site at which the transportation begins and the destination or the hospital. Utilizing the same system, a virtual simulation of a large-scale disaster at airport was used as sample data. As a result, it was confirmed that the survival rate would improve under certain conditions, if the values for some of the variables, such as geographic conditions, were altered and then calculated. 相似文献
50.
Gaku Yamanaka Yu Ishida Kanako Kanou Shinji Suzuki Yusuke Watanabe Tomoko Takamatsu Shinichiro Morichi Soken Go Shingo Oana Takashi Yamazaki Hisashi Kawashima 《International journal of molecular sciences》2021,22(12)
Febrile Infection-Related Epilepsy Syndrome (FIRES) is a unique catastrophic epilepsy syndrome, and the development of drug-resistant epilepsy (DRE) is inevitable. Recently, anakinra, an interleukin-1 receptor antagonist (IL-1RA), has been increasingly used to treat DRE due to its potent anticonvulsant activity. We here summarized its effects in 38 patients (32 patients with FIRES and six with DRE). Of the 22 patients with FIRES, 16 (73%) had at least short-term seizure control 1 week after starting anakinra, while the remaining six suspected anakinra-refractory cases were male and had poor prognoses. Due to the small sample size, an explanation for anakinra refractoriness was not evident. In all DRE patients, seizures disappeared or improved, and cognitive function improved in five of the six patients following treatment. Patients showed no serious side effects, although drug reactions with eosinophilia and systemic symptoms, cytopenia, and infections were observed. Thus, anakinra has led to a marked improvement in some cases, and functional deficiency of IL-1RA was indicated, supporting a direct mechanism for its therapeutic effect. This review first discusses the effectiveness of anakinra for intractable epileptic syndromes. Anakinra could become a new tool for intractable epilepsy treatment. However, it does not currently have a solid evidence base. 相似文献