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161.
The effect of the removal of pineal gland, performed in adult age or during perinatal life, was investigated in the neonatal androgen sterility (NA-CEA) syndrome, in combination with drugs acting on serotonergic neurons. Perinatal pinealectomy (Px) was more potent in preventing the development of NA-CEA state than Px performed in the adult age. These data indicate that the masculinized hypothalamus becomes less sensitive to pineal influences during the lifespan. Effect of Px was potentiated by drugs increasing the central serotonergic tone. The results lead to the assumption that pineal hormones are influential on the maturation of serotonergic neurons, which might interfere with the sterilizing property of neonatal androgen treatment during the "critical" period of sexual differentiation. 相似文献
162.
Monoclonal antibodies (MoAbs) against potato virus A (PVA) were examined in their reactivity with PVA and its denatured capsid protein (PVA-CP) bound to the nitrocellulose membrane. Five MoAbs reacted with native PVA, three of them also with PVA-CP. One MoAb gave no reaction in dot-blot test. In polyacrylamide electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE) PVA-CP migrated as two major bands. In immunoblot analysis, two MoAbs reacted only with the slower band, one only with the faster one. We presume that those bands do not correspond to the intact CP but they do to truncated N- and C-terminal CP molecules, respectively, and that the corresponding epitopes reacting with MoAbs are localized near to both termini of CP molecules. After mild trypsinolysis of PVA particles no MoAb reacted with resulting "core" CP. 相似文献
163.
Antonio J. Jara Miguel A. Zamora Antonio F. G. Skarmeta 《Personal and Ubiquitous Computing》2011,15(4):431-440
Diabetes therapy management in AAL environments, such as old people and diabetes patients homes, is a very difficult task
since many factors affect a patient’s blood sugar levels. Factors such as illness, treatments, physical and psychological
stress, physical activity, drugs, intravenous fluids and change in the meal plan cause unpredictable and potentially dangerous
fluctuations in blood sugar levels. Right now, operations related to dosage are based on insulin infusion protocol boards,
which are provided by physicians to the patients. These boards are not considering very influential factors such as glycemic
index from the diet, consequently patients need to estimate the dosage leading to dose error, which culminates in hyperglycemia
and hypoglycemia episode. Therefore, right insulin infusion calculation needs to be supported by the next generation of personal-care
devices. For this reason, a personal device has been developed to assist and consider more factors in the insulin therapy
dosage calculation. The proposed solution is based on Internet of things in order to, on the one hand, support a patient’s
profile management architecture based on personal RFID cards and, on the other hand, provide global connectivity between the
developed patient’s personal device based on 6LoWPAN, nurses/physicians desktop application to manage personal health cards,
glycemic index information system, and patient’s web portal. This solution has been evaluated by a multidisciplinary group
formed by patients, physicians, and nurses. 相似文献
164.
Julián D. Arias-Londoño Author Vitae Juan I. Godino-Llorente Author Vitae Nicolás Sáenz-Lechón Author Vitae Author Vitae Germán Castellanos-Domínguez Author Vitae 《Pattern recognition》2010,43(9):3100-3112
This paper presents new a feature transformation technique applied to improve the screening accuracy for the automatic detection of pathological voices. The statistical transformation is based on Hidden Markov Models, obtaining a transformation and classification stage simultaneously and adjusting the parameters of the model with a criterion that minimizes the classification error. The original feature vectors are built up using classic short-term noise parameters and mel-frequency cepstral coefficients. With respect to conventional approaches found in the literature of automatic detection of pathological voices, the proposed feature space transformation technique demonstrates a significant improvement of the performance with no addition of new features to the original input space. In view of the results, it is expected that this technique could provide good results in other areas such as speaker verification and/or identification. 相似文献
165.
166.
An adaptive, real-time, traffic monitoring system 总被引:1,自引:0,他引:1
In this paper we describe a computer vision-based traffic monitoring system able to detect individual vehicles in real-time.
Our fully integrated system first obtains the main traffic variables: counting, speed and category; and then computes a complete
set of statistical variables. The objective is to investigate some of the difficulties impeding existing traffic systems to
achieve balanced accuracy in every condition; i.e. day and night transitions, shadows, heavy vehicles, occlusions, slow traffic
and congestions. The system we present is autonomous, works for long periods of time without human intervention and adapts
automatically to the changing environmental conditions. Several innovations, designed to deal with the above circumstances,
are proposed in the paper: an integrated calibration and image rectification step, differentiated methods for day and night,
an adaptive segmentation algorithm, a multistage shadow detection method and special considerations for heavy vehicle identification
and treatment of slow traffic. A specific methodology has been developed to benchmark the accuracy of the different methods
proposed. 相似文献
167.
M. Fernández-Delgado M. Reboreda E. Cernadas S. Barro 《Neural computing & applications》2010,19(5):741-754
In the industrial environment, specifically in the automotive industry, an accurate prediction of execution times for each
production task is very useful in order to plan the work and to optimize the human, technical and material resources. In this
paper, we applied several regression neural networks to predict the execution times of the tasks in the production of parts
for plastic injection molds. These molds are used to make a variety of car components in automotive industry. The prediction
is based on the geometric features of the mold parts to be made. The accuracy of the predicted times is high enough to be
used as a tool for the design stage of the mold parts, e.g. guiding the design process in order to get the lowest production
time. 相似文献
168.
169.
170.
Julia Clemente Jaime Ramírez Angélica de Antonio 《Expert systems with applications》2011,38(7):8066-8078
The advances in the educational field and the high complexity of student modeling have provoked it to be one of the aspects more investigated in Intelligent Tutoring Systems (ITSs). The Student Models (SMs) should not only represent the student’s knowledge, but rather they should reflect, as faithfully as possible, the student’s reasoning process. To facilitate this goal, in this article a new approach to student modeling is proposed that benefits from the advantages of Ontological Engineering, advancing in the pursue of a more granular and complete knowledge representation. It’s focused, mainly, on the SM cognitive diagnosis process, and we present a method providing a rich diagnosis about the student’s knowledge state – especially, about the state of learning objectives reached or not. The main goal is to achieve SMs with a good adaptability to the student’s features and a high flexibility for its integration in varied ITSs. 相似文献