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291.
292.
McBride Colleen M.; Pollak Kathryn I.; Lyna Pauline; Lipkus Issac M.; Samsa Gregory P.; Bepler Gerold 《Canadian Metallurgical Quarterly》2001,20(5):334
The psychometric characteristics of the Reasons For Quitting scale (RFQ) were assessed among a sample of African American smokers with low income (N?=?487). The intrinsic and extrinsic scales and their respective subscales were replicated. As hypothesized, higher levels of motivation were associated significantly, in patterns that supported the measure's construct validity, with advanced stage of readiness to quit smoking, greater perceived vulnerability to health effects of smoking, and greater social support for cessation. On the basis of the present study, the RFQ might best predict short-term cessation among older and female smokers. Refinement of the RFQ is needed to assess intrinsic motivators other than health concerns and to identify salient motivators for young and male smokers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
293.
294.
Miina Rautiainen Juha Suomalainen Pauline Stenberg Jouni Peltoniemi 《Remote sensing of environment》2007,110(3):332-343
The Arctic region is predicted to experience considerable climatic and environmental changes as the global atmospheric CO2 increases. Growing awareness of the role of tundra and taiga ecosystems and their transition zone in the climate change process has resulted in a recent increase in remote sensing studies focusing on the Arctic latitudes. Remote sensing of biophysical properties of the canopy layer in the forested part of the region is often, however, challenged by the dominating role of the understory in the spectral signal. In this paper, we examine the influence of understory vegetation on forest reflectance in the Arctic region of Finland during no-snow conditions. The study is based on SPOT HRVIR images, field goniospectrometry, 300 ground reference plots and a physically-based forest reflectance model (PARAS). The results indicate that lichen-dominated forest site types can be distinguished from sites dominated by dwarf shrubs. The paper also contains results from applying an analytical method for calculating photon recollision probability from canopy transmittance data for forest stands, and then using it to simulate the reflectance of the same stands. 相似文献
295.
Towards a practical measure of hypertext usability 总被引:5,自引:0,他引:5
Pauline A. Smith 《Interacting with computers》1996,8(4):365-381
296.
Abstract After daguerreotype portraiture was introduced into the British Isles, entrepreneurs striving to succeed as photographic artists soon realized that if their productions were to be commercially and socially acceptable, it was imperative that they should be received favourably by the ‘gentle sex’. 相似文献
297.
Atkinson Donald R.; Poston W. Carlos; Furlong Michael J.; Mercado Pauline 《Canadian Metallurgical Quarterly》1989,36(1):68
A questionnaire using a paired-comparison procedure to measure preferences for 14 counselor characteristics was administered to 500 students in introductory psychology and business classes at two state universities on the West Coast. A total of 339 usable responses were received from 118 Asian-American students, 64 Mexican-American students, and 157 Caucasian-American students. Rank order preferences for counselor characteristics were almost identical across the three ethnic groups. Preferences for a counselor who had similar attitudes, similar personality, and more education, and was older than the respondent ranked among the top four counselor characteristics for all ethnic groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
298.
Pauline Stenberg Terhikki Manninen 《International journal of remote sensing》2015,36(19-20):5178-5191
The spectral invariants theory predicts that the bidirectional reflectance factor (BRF) of a vegetation canopy can be expressed in terms of the canopy interceptance (i0), the recollision probability (p), and the directional escape probability (ρ). These spectral invariant parameters together form a novel canopy structural parameter – the directional area scattering factor (DASF). The DASF can be retrieved from remotely sensed hyperspectral imagery and has been found to be useful, e.g. for the separation of tree species. The spectral invariants theory, however, does not provide an interpretation of which specific canopy structural properties are captured by the DASF. In this study, we examined the possible link between the DASF and the canopy clumping index (β). A simple model was designed to simulate the effect of β on canopy first order scattering, which was assumed to govern the directional behaviour of the DASF. The model is based on a modified spectral invariants approach, where the assumption of constant p is relaxed so that the first order recollision probability (p1) and single scattering are calculated separately, and canopy BRF is expressed as the sum of the first and multiple order components. Simulations were performed on model canopies, where radiation penetration is described using a traditional statistical approach but allowing non-random foliage distributions caused by clumping. The results indicated a strong dependency between the modelled DASF and the canopy clumping index. 相似文献
299.
Properly designing a wavelet neural network (WNN) is crucial for achieving the optimal generalization performance. In this paper, two different approaches were proposed for improving the predictive capability of WNNs. First, the types of activation functions used in the hidden layer of the WNN were varied. Second, the proposed enhanced fuzzy c-means clustering algorithm—specifically, the modified point symmetry-based fuzzy c-means (MSFCM) algorithm—was employed in selecting the locations of the translation vectors of the WNN. The modified WNN was then applied to heterogeneous cancer classification using four different microarray benchmark datasets. The comparative experimental results showed that the proposed methodology achieved an almost 100% classification accuracy in multiclass cancer prediction, leading to superior performance with respect to other clustering algorithms. Subsequently, performance comparisons with other classifiers were made. An assessment analysis showed that this proposed approach outperformed most of the other classifiers. 相似文献
300.
A new semi-physical forest reflectance model, PARAS, is presented in the paper. PARAS is a simple parameterization model for taking into account the effect of within-shoot scattering on coniferous canopy reflectance. Multiple scattering at the small scale represented by a shoot is a conifer-specific characteristic which causes the spectral signature of coniferous forests to differ from that of broadleaved forests. This has for long led to problems in remote sensing of canopy structural variables in coniferous dominated regions. The PARAS model uses a relationship between photon recollision probability and leaf area index (LAI) for simulating forest reflectance. The recollision probability is a measurable, wavelength independent variable which is defined as the probability with which a photon scattered in the canopy interacts with a phytoelement again. In this study, we present application results using PARAS in simulating reflectance of coniferous forests for approximately 800 Scots pine and Norway spruce dominated stands. The results of this study clearly indicate that a major improvement in simulating canopy reflectance in near-infrared (NIR) is achieved by simply accounting for the within-shoot scattering. In other words, the low NIR reflectance observed in coniferous areas is mainly due to within-shoot scattering. In the red wavelength the effect of within-shoot scattering was not pronounced due to the high level of needle absorption in the red range. To conclude the paper, further application possibilities of the presented parameterization model are discussed. 相似文献