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101.
Kiyohiko Hattori Eri Homma Toshinori Kagawa Masayuki Otani Naoki Tatebe Yasunori Owada Lin Shan Katsuhiro Temma Kiyoshi Hamaguchi 《Artificial Life and Robotics》2016,21(4):451-459
Recently, many extensive studies have been conducted on robot control via self-positioning estimation techniques. In the simultaneous localization and mapping (SLAM) method, which is one approach to self-positioning estimation, robots generally use both autonomous position information from internal sensors and observed information on external landmarks. SLAM can yield higher accuracy positioning estimations depending on the number of landmarks; however, this technique involves a degree of uncertainty and has a high computational cost, because it utilizes image processing to detect and recognize landmarks. To overcome this problem, we propose a state-of-the-art method called a generalized measuring-worm (GMW) algorithm for map creation and position estimation, which uses multiple cooperating robots that serve as moving landmarks for each other. This approach allows problems of uncertainty and computational cost to be overcome, because a robot must find only a simple two-dimensional marker rather than feature-point landmarks. In the GMW method, the robots are given a two-dimensional marker of known shape and size and use a front-positioned camera to determine the marker distance and direction. The robots use this information to estimate each other’s positions and to calibrate their movement. To evaluate the proposed method experimentally, we fabricated two real robots and observed their behavior in an indoor environment. The experimental results revealed that the distance measurement and control error could be reduced to less than 3 %. 相似文献
102.
Evert‐Jan van Donkelaar Juergen Schultze Toru Shibuya Yutaka Konai Mitsuharu Miyazaki 《Journal of the Society for Information Display》2002,10(3):223-229
In 1998, Toyo Gosei Co. published a paper on the development of a new water‐soluble photopolymer of high sensitivity, PVA‐ARBB. In close co‐operation with LG. Philips Displays, the new material was further developed to be applicable in patterning the phosphor layer of a CRT screen. The new material shows about 3 times higher light sensitivity, gives 4–5% higher luminance, has no dark reaction, and is chromium‐free. It is the first chromium‐free photoresist used for phosphor patterning in CRT mass production. A comparison is presented between the conventional resist and the new resist. A survey is given of the most important process conditions. 相似文献
103.
The electrical conductivities of non-stoichiometric samarium manganites were measured as a function of temperature and the existence of a Z-type jump in the conductivity curve was found near 1300 K, and a heat anomaly was also observed by differential thermal analysis, which should reflect the same phase transition as in LaMnO3. 相似文献
104.
Masuhiro Fukaya Toru Miyazaki Pi Zhi Zhao Takao Kozakai 《Journal of Materials Science》1990,25(1):522-528
The free energy of the Fe-base ternary ordering alloys whereB2 andD03 ordered structures are formed is evaluated. The statistical theory is employed using a pairwise interaction approximation taking into account not only the atomic interaction but also the magnetic interaction, based upon the Bragg-Williams-Gorsky model. The application of this model on Fe-Si-Co ordering alloys are demonstrated. The propriety of the calculation results are performed by comparing the experimental results. The influences of the magnetic energy to the stability of ordered structures are also demonstrated. 相似文献
105.
Langmuir–Blodgett (LB) films of the copolymer with ferrocenyl-methyl-acrylate (FcMA) and N-dodecyl-acrylamide (DDA) were fabricated. The magnetic moment of these LB films became about twenty times larger than that of the powder. In addition, the LB films had a magnetic anisotropy depending on the dipping direction. The FTIR results suggested that the polymer chains in the LB films were preferably aligned with the perpendicular of the dipping direction. These results were discussed by the intermolecular electron transfer. 相似文献
106.
Xiufeng HAN Lanying LIN T.Miyazaki Fuming YANG Rengeng XU Xinhua WANG Hongge PAN Changping CHEN 《材料科学技术学报》1999,15(1):5-9
1.IntroductionIntensiveinvestigatiOnsontheR-Fe-T(R=rareearth,T=transitionmetalasastabilizingelement)phasediagrams,locatedattheironrichcorner,ledtothediscoveryofthenovelR2(Fe,T)l9phase[1l2]duetothegreatinterestinhighperfOrmanceper-manentmagneticmaterials.ItsrealstoichiometriccompOsitionandcrystallographicstructurewerede-terminedasaNd3(Fe,Ti)29-typestructurewithmon-oclinicsymmetry[3]andtheA2/mspacegrOup[4]byX-rnypowderdiffractiOn(XRD)andthenthiswasconfirmedbyneutrOnpOwderdiffraction[5'6… 相似文献
107.
Under magnetic fields perpendicular to the conductive plane in quasi-two-dimensional organic conductors: -(BEDT-TTF)2
MHg(SCN)4 (M= K, Rb, and Tl), the experimentally reported H–T phase diagram has been explained partially. By the self-consistent numerical calculation including the quantum magnetic oscillation and the magnetic breakdown; in addition to the imperfectness of the SDW nesting, we try to completely understand the phase diagram. 相似文献
108.
Akira Matsumoto Takayuki Nakagawa Masatoshi Sato Yasunori Kimura Kenji Nishida Atsuhiro Goto 《New Generation Computing》1991,9(2):149-169
The parallel inference machine (PIM) is now being developed at ICOT. It consists of a dozen or more clusters, each of which
is a tightly coupled multiprocessor (comprising about eight processing elements) with shared global memory and a common bus.
Kernel language 1 (KL1), a parallel logic programming language based on Guarded Horn Clauses (GHC), is executed on each PIM
cluster.
This paper describes the memory access characteristics in KL1 parallel execution and a locally parallel cache mechanism with
hardware lock. The most important issue of locally parallel cache design is how to reduce common bus traffic. A write-back
cache protocol having five cache states specially optimized for KL1 execution on each PIM cluster is described. We introduced
new software controlled memory access commands, named DW, ER, and RP. A hardware lock mechanism is attached to the cache on
each processor. This lock mechanism enables efficient word-by-word locking, reducing common bus traffic by using the cache
states. 相似文献
109.
In this paper, we first discuss the integral equation formulation for the buckling problem of a single plate, using the biharmonic fundamental solution for the plate bending problems. The so called boundary-element method previously proposed by the senior author is applied to the numerical solution of the resulting set of integral equations. The total set of simultaneous equations are derived for nodal unknowns taken out of the whole domain, and reduced to an algebraic set of eigenvalue equations. The proposed method is method to the solution of elastic buckling of assembled plate structures. A few examples are computed and results obtained are compared with other solutions to demonstrate the potential usefulness of the proposed method. 相似文献
110.
To clarify the thermal degradation mechanisms of uniaxially drawn poly(vinylidene fluoride) (PVDF) films, variations due to annealing in the polymeric structures of the films were investigated using the small‐angle X‐ray scattering (SAXS) and Fourier transform infrared (FTIR) spectroscopy. The films were composed of lamellar crystals that were stacked perpendicular to the stretch direction. Although the crystallinity of the films decreased during annealing in the temperature range above the preannealing temperature, the lamellar structure was maintained even after the annealing process. There are two kinds of irreversible relaxation mechanisms during the annealing process of the films, including both a decrease in crystallinity within the lamellae and also thickening of the lamellae. A significant lamella thickening effect was observed when the films were annealed above ~ 100°C. FTIR spectra suggested some disordered structures are developed during thickening of the lamellae. Furthermore, a long‐range periodic structure was formed in the films that were annealed above the melting temperature of PVDF. The polymeric structures formed during the fabrication process (including high‐order structures and disorders in molecular conformation) were clarified as having a significant influence on the annealing behavior of ferroelectric PVDF films. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献