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71.
We introduce a novel segmentation technique, called Pearling, for the semi-automatic extraction of idealized models of networks of strokes (variable width curves) in images. These networks may for example represent roads in an aerial photograph, vessels in a medical scan, or strokes in a drawing. The operator seeds the process by selecting representative areas of good (stroke interior) and bad colors. Then, the operator may either provide a rough trace through a particular path in the stroke graph or simply pick a starting point (seed) on a stroke and a direction of growth. Pearling computes in realtime the centerlines of the strokes, the bifurcations, and the thickness function along each stroke, hence producing a purified medial axis transform of a desired portion of the stroke graph. No prior segmentation or thresholding is required. Simple gestures may be used to trim or extend the selection or to add branches. The realtime performance and reliability of Pearling results from a novel disk-sampling approach, which traces the strokes by optimizing the positions and radii of a discrete series of disks (pearls) along the stroke. A continuous model is defined through subdivision. By design, the idealized pearl string model is slightly wider than necessary to ensure that it contains the stroke boundary. A narrower core model that fits inside the stroke is computed simultaneously. The difference between the pearl string and its core contains the boundary of the stroke and may be used to capture, compress, visualize, or analyze the raw image data along the stroke boundary.  相似文献   
72.
Advances in music retrieval research greatly depend on appropriate database resources and their meaningful organization. In this paper we describe data collection efforts related to the design of query-by-humming (QBH) systems. We also provide a statistical analysis for categorizing the collected data, especially focusing on intersubject variability issues. In total, 100 people participated in our experiment, resulting in around 2000 humming samples drawn from a predefined melody list consisting of 22 different well-known music pieces and over 500 samples of melodies that were chosen spontaneously by our subjects. These data are being made available to the research community. The data from each subject were compared to the expected melody features, and an objective measure was derived to quantify the statistical deviation from the baseline. The results showed that the uncertainty in human humming varies depending on the musical structure of the melodies and the musical background of the subjects. Such details are important for designing robust QBH systems. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and full citation on the first page. To copy otherwise, or republish, to post on servers, or to redistribute to lists requires prior specific permission and/or a fee.  相似文献   
73.
Turen  Y U.  Zengin  H.  Sun  Ya.  Ahlatci  H.  Unal  M. 《Metal Science and Heat Treatment》2019,61(5-6):318-324
Metal Science and Heat Treatment - We study the influence of 1 wt.% Ti, In and Sn additions on the microstructure, mechanical properties and corrosion resistance of the as-cast and hot-rolled AM60...  相似文献   
74.
Acid functionalized multiwall carbon nanotube, (MWCNT)-COOH/nickel ferrite (NiFe2O4), magnetic hybrids were synthesized by a co-precipitation method. X-ray diffraction, Fourier transform infrared spectrometry, thermal gravimetry, transmission electron microscopy, vibrating sample magnetometry and Impedance Spectroscopy were used to characterize the physical and electrical properties of the MWCNT-COOH/NiFe2O4 hybrid. NiFe2O4 NPs are stably attached to the surface of via carboxyl groups (COOH). The magnetic saturation value of the product was found as 8 emu/g. A tunneling conduction mechanism was believed to occur in the hybrid. The real modules (M′) of the product illustrate power law variation with a power exponent of approximately unity. These magnetic MWCNT-COOH/NiFe2O4 hybrids exhibit a promising prospective in the application of bio-nanoscience and technology.  相似文献   
75.
In this study, we attempt to develop an ozone forecast model using two different approaches. The first approach is to use a multiple linear regression method and the second is to use a feed-forward artificial neural network. Models are developed for the ozone period of April through to September of the years 2002 and 2003 and verified for May to August 2004. In both models, 19 predictors are used. Calculated agreement indices (AI) for the model development period are 0.82 for the linear regression model and 0.88 for the artificial neural network model. On the other hand, AI values decrease to 0.53 and 0.64 for the validation period. Poor performance of the models in the validation phase might be due to the different maximum daily ozone averages of these two periods. While the average of maximum ozone values is 61.1 μg m?3 in the model development phase, it is 42.2 μg m?3 in the model validation phase.  相似文献   
76.
In this study, Na‐montmorillonite was organically modified with cetyltrimethylammoniumbromide (CTAB) and intercalated with in‐situ polymerized indene. Polyindene(PIn)/Organo‐MMT nanocomposites were obtained with three different compositions and coded as: K1: [PIn(94.5%)/O‐MMT(5.5%)], K2: [PIn(92.8%)/O‐MMT(7.2%)], and K3: [PIn(87.9%)/O‐MMT(12.1%)]. These nanocomposites were subjected to full characterization with various techniques. Electrokinetic studies were conducted to reveal the zeta (ζ)‐potential characteristics of the nanocomposites. ζ‐potentials of the materials were observed to decrease with increasing O‐MMT content. The cationic (CTAB) and anionic (sodium dodecylsulfate) surfactants were shifted the ζ‐potentials of the colloidal dispersions to more positive and more negative regions, respectively whereas nonionic surfactant (Triton X‐100) caused almost no change. The pH and temperature were observed to shift the ζ‐potential values of the nanocomposites to more negative and slightly more positive regions, respectively. With the addition of mono (NaCl), di (BaCl2) and three (AlCl3) valent salts, the ζ‐potential of the nanocomposites were shifted to more negative, more positive, and much more positive regions, respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
77.
Burcu Unal 《Polymer》2009,50(3):905-12298
We examine the pH-dependent swelling of end-linked hydrogels containing high concentrations of amine-functional macromonomers. Gels are formed by end-linking of epoxide-terminated, linear poly(ethylene glycol) (PEG) to either amine-terminated poly(amidoamine) (PAMAM) dendrimers or highly branched poly(ethyleneimine) (PEI). After extraction in neutral water, the hydrogels are swollen in aqueous solutions of HCl or NH4OH to vary the external pH. Equilibrium volume swelling ratios (Qs) pass through a maximum value (Qmax) at an external pH denoted as pH which is approximately 4-5 for the gels studied. The swelling behavior is modeled using Donnan equilibrium theory to describe the ion swelling pressure, with the Flory-Rehner phantom network expression representing the elastic and mixing contributions to the free energy. The model accurately predicts the maximum in swelling near pH = 4-5, but overestimates Qmax for several of the gels due to neglecting the finite extensibility of the short linear PEG chains.  相似文献   
78.
Three types of Gafchromic films have been studied to investigate their potential for use as a visually readable dosemeter for persons acting as first responders in connection with radiological or nuclear emergencies. The two most sensitive film types show a pronounced variation in sensitivity by photon energy and are therefore not suitable for use in cases of unknown exposures. The third film type tested (RTQA2), which is intended for quality control in radiation therapy has a sensitivity that is independent of the radiation quality, and is therefore considered as the most optimal for visual reading in situ. Tests carried out on a group of 10 human observers showed that absorbed doses down to 40 mGy can be detected by the eye. Read by a portable densitometer, qualitative absorbed dose estimates down to 9 mGy can be achieved. The colour change is obtained instantaneously, giving first responders immediate information about the presence of beta-, gamma- and X-ray radiation.  相似文献   
79.
In this study, a controlled fuzzy expert system (FES) was designed to provide the conditions necessary for operating rooms. For this purpose, existing operating rooms have been studied to see if there are more useful, reliable and comfortable ones. How an operating room can be controlled with FES and its advantages and disadvantages have also been researched. For a theoretically visible FES to show system’s advantage a prototype operating room was built and a suitable configuration was designed. In this system, heat, humidity, oxygen and particles were used as input parameters, and a fresh air entrance and fan circulation were chosen as output parameters. With the help of an expert, appropriate linguistic expressions and the membership function of these expressions were defined. The sensors were classified and sensor information was transferred to computer by means of an interface designed. In order to transfer the data to the system simultaneously, an interface was written in C#. Whether it provides the most suitable control for the system prototype was determined by simulating the operation with varying numbers of patients and operation personnel. In these trials, input, output and other necessary parameters were collected in the computer.In the study, we obtained excellent results in prototype operating room control with FES. The analyses of the results carried out indicated that the controls performed with FES provide more economical, comfortable, reliable and consistent controls and that they are feasible in a real operating room.  相似文献   
80.
The emergence of increasing number of collaborating organizations has made clear the need for supporting interoperability infrastructures, enabling sharing and exchange of data among organizations. Schema matching and schema integration are the crucial components of the interoperability infrastructures, and their semi-automation to interrelate or integrate heterogeneous and autonomous databases in collaborative networks is desired. The Semi-Automatic Schema Matching and INTegration (SASMINT) System introduced in this paper identifies and resolves several important syntactic, semantic, and structural conflicts among schemas of relational databases to find their likely matches automatically. Furthermore, after getting the user validation on the matched results, it proposes an integrated schema. SASMINT uses a combination of a variety of metrics and algorithms from the Natural Language Processing and Graph Theory domains for its schema matching. For the schema integration, it utilizes a number of derivation rules defined in the scope of the research work explained in this paper. Furthermore, a derivation language called SASMINT Derivation Markup Language (SDML) is defined for capturing and formulating both the results of matching and the integration that can be further used, for example for federated query processing from independent databases. In summary, the paper focuses on addressing: (1) conflicts among schemas that make automatic schema matching and integration difficult, (2) the main components of the SASMINT approach and system, (3) in-depth exploration of SDML, (4) heuristic rules designed and implemented as part of the schema integration component of the SASMINT system, and (5) experimental evaluation of SASMINT.  相似文献   
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