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31.
Theory of Computing Systems - As a variant of the equal entropy cover problem, we ask whether all multidimensional sofic shifts with countably many configurations have SFT covers with countably... 相似文献
32.
Taneli Juntunen Henri Jussila Mikko Ruoho Shouhu Liu Guohua Hu Tom Albrow‐Owen Leonard W. T. Ng Richard C. T. Howe Tawfique Hasan Zhipei Sun Ilkka Tittonen 《Advanced functional materials》2018,28(22)
Graphene‐based organic nanocomposites have ascended as promising candidates for thermoelectric energy conversion. In order to adopt existing scalable printing methods for developing thermostable graphene‐based thermoelectric devices, optimization of both the material ink and the thermoelectric properties of the resulting films are required. Here, inkjet‐printed large‐area flexible graphene thin films with outstanding thermoelectric properties are reported. The thermal and electronic transport properties of the films reveal the so‐called phonon‐glass electron‐crystal character (i.e., electrical transport behavior akin to that of few‐layer graphene flakes with quenched thermal transport arising from the disordered nanoporous structure). As a result, the all‐graphene films show a room‐temperature thermoelectric power factor of 18.7 µW m?1 K?2, representing over a threefold improvement to previous solution‐processed all‐graphene structures. The demonstration of inkjet‐printed thermoelectric devices underscores the potential for future flexible, scalable, and low‐cost thermoelectric applications, such as harvesting energy from body heat in wearable applications. 相似文献
33.
A.M. Turpeinen M. Kumpu M. Rönnback L. Seppo H. Kautiainen T. Jauhiainen H. Vapaatalo R. Korpela 《Journal of Functional Foods》2009,1(3):260-265
The effects of a spread containing bioactive tripeptides isoleucine–proline–proline (IPP), valine–proline–proline (VPP) and plant sterols were studied in subjects with mild hypertension and elevated LDL cholesterol. Sixty-two subjects consumed 20 g/day spread containing 4.2 mg milk peptides and 2 g plant sterol esters or placebo for 10 weeks. Blood pressure was measured twice a week. Arterial stiffness was assessed by pulse wave analysis and by pulse wave velocity. Blood samples were analysed for serum lipids and high-sensitive CRP. A significant decrease was seen in systolic blood pressure (p = 0.026), but not in diastolic blood pressure (p = 0.53). Total cholesterol (p = 0.003) and LDL cholesterol (p = 0.002) decreased, whereas HDL cholesterol, triacylglycerols and CRP remained unchanged. No overall effects on arterial stiffness were seen. The results suggest that a spread containing bioactive milk peptides and plant sterols has a beneficial effect on two major cardiovascular risk factors, blood pressure and plasma lipids, in hypertensive, dyslipidemic subjects. Functional foods affecting two major risk factors can be valuable tools in managing cardiovascular risk. 相似文献
34.
35.
Ilkka Malinen 《Chemical engineering science》2008,63(13):3419-3430
The aim of this paper is to introduce modifications that enhance the usability of the bounded homotopy methods proposed by Paloschi [1995. Bounded homotopies to solve systems of algebraic nonlinear equations. Computers and Chemical Engineering 19, 1243-1254; 1997. Bounded homotopies to solve systems of sparse algebraic nonlinear equations. Computers and Chemical Engineering 21, 531-541], especially in the area of chemical engineering. In modified bounded homotopies, the homotopy path is tracked by exploiting mapped variables instead of unmapped ones. Path tracking based on mapped variables makes it significantly easier to track the bounded homotopy path even though the bounding zone has to be narrow. Mapping also improves the bounding effect of bounded homotopies and makes it possible to avoid unreasonable variable values in homotopy path tracking. The performance of the modifications is illustrated with test cases. These examples clearly show that the modifications enlarge the capability and accuracy of bounded homotopies when solving both small- and large-scale sets of nonlinear equations describing chemical engineering problems. 相似文献
36.
Modifying the output pulses of a passively Q-switched Nd:YAG laser, operating at 1064 nm, was realized by heating the laser crystal. With the demonstrated laser setups, a 100 K temperature rise led to a more than 50% increase in the pulse energy and a more than 10% decrease in the pulse length. This method offers an effective way to tune the output of the laser without mechanical adjustment or a change of components. 相似文献
37.
Cyclodextrins have diverse, important applications in food industry. These applications are based on the ability of cyclodextrins to form molecular complexes with small—molecular compounds. Cyclodextrins are harmless in oral administration and advantageous effects by cyclodextrins are achieved by simple mixing of small amounts of them to the material being stabilized. Development of convenient and cost‐effective processes for production of cyclodextrins are undergoing and there are promises in the near future for obtaining cyclodextrins which are realistic in price to be used in foods. While cyclodextrins have been used for more than ten years in Japan as natural additives in foods, the legislation for their approval in foods is still under development in Europe and USA. 相似文献
38.
TA L?hteenm?ki R Korpela MJ Tikkanen K Karjala J Laakso E Solatunturi H Vapaatalo 《Canadian Metallurgical Quarterly》1998,63(12):995-1003
The effects were studied of native, partially-oxidized and totally-oxidized human low-density lipoprotein (LDL) on the proliferation of cultured rat aortic smooth muscle cells (VSMC), measured as an altered DNA synthesis. The LDL was obtained from three different human long-term diet groups (a control diet rich in saturated fats, a vegetarian diet, and a fish diet). The oxidized LDLs were prepared by oxidizing the LDL with copper sulfate. The DNA synthesis was measured by [3H]-thymidine incorporation into the DNA. The partially-oxidized LDL was the most potent promoter of DNA synthesis compared to the native or totally-oxidized LDL of the same diet group. The partially-oxidized LDL had a true mitogenic effect in the absence of exogenous growth factors. The native and totally-oxidized LDL induced a significant increase in DNA synthesis, if they were obtained from the fish diet group. This study suggests an enhanced proliferative effect of partially-oxidized LDL on VSMC growth. 相似文献
39.
Jussi Korpela Andreas Henelius Lauri Ahonen Arto Klami Kai Puolamäki 《Data mining and knowledge discovery》2016,30(5):1112-1133
In many data analysis tasks it is important to understand the relationships between different datasets. Several methods exist for this task but many of them are limited to two datasets and linear relationships. In this paper, we propose a new efficient algorithm, termed cocoreg, for the extraction of variation common to all datasets in a given collection of arbitrary size. cocoreg extends redundancy analysis to more than two datasets, utilizing chains of regression functions to extract the shared variation in the original data space. The algorithm can be used with any linear or non-linear regression function, which makes it robust, straightforward, fast, and easy to implement and use. We empirically demonstrate the efficacy of shared variation extraction using the cocoreg algorithm on five artificial and three real datasets. 相似文献
40.
Airborne discrete-return LIDAR data in the estimation of vertical canopy cover, angular canopy closure and leaf area index 总被引:2,自引:0,他引:2
Remote sensing of forest canopy cover has been widely studied recently, but little attention has been paid to the quality of field validation data. Ecological literature has two different coverage metrics. Vertical canopy cover (VCC) is the vertical projection of tree crowns ignoring within-crown gaps. Angular canopy closure (ACC) is the proportion of covered sky at some angular range around the zenith, and can be measured with a field-of-view instrument, such as a camera. We compared field-measured VCC and ACC at 15° and 75° from the zenith to different LiDAR (Light Detection and Ranging) metrics, using several LiDAR data sets and comprehensive field data. The VCC was estimated to a high precision using a simple proportion of canopy points in first-return data. Confining to a maximum 15° scan zenith angle, the absolute root mean squared error (RMSE) was 3.7-7.0%, with an overestimation of 3.1-4.6%. We showed that grid-based methods are capable of reducing the inherent overestimation of VCC. The low scan angles and low power settings that are typically applied in topographic LiDARs are not suitable for ACC estimation as they measure in wrong geometry and cannot easily detect small within-crown gaps. However, ACC at 0-15° zenith angles could be estimated from LiDAR data with sufficient precision, using also the last returns (RMSE 8.1-11.3%, bias -6.1-+4.6%). The dependency of LiDAR metrics and ACC at 0-75° zenith angles was nonlinear and was modeled from laser pulse proportions with nonlinear regression with a best-case standard error of 4.1%. We also estimated leaf area index from the LiDAR metrics with linear regression with a standard error of 0.38. The results show that correlations between airborne laser metrics and different canopy field characteristics are very high if the field measurements are done with equivalent accuracy. 相似文献