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991.
The present study examined the relationship between a set of individual and contextual variables and high-risk alcohol use among young offenders placed on community orders in New South Wales, Australia. Participants (n = 777) were compared on a set of factors known to be strong predictors of high-risk alcohol use among adolescents. The authors assessed the strength of the relationship between gender, age, ethnicity, geographical region of residence, school attendance, father absence, history of childhood trauma, and the presence of severe conduct disorder on weekly levels of alcohol use. Living in rural locations, not currently attending school, being female, and not having been raised with a biological father present were associated with significantly increased odds of alcohol abuse. Father absence was a more important risk factor for rural young offenders, but school dropout was associated with more hazardous drinking among young offenders in urban areas. Accordingly, the authors suggest family-focused intervention programs for young offenders living in rural areas and school-based programs for vulnerable young people living in urban areas, although programs should consider including both factors for both groups if feasible and warranted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
The coach–athlete relationship has been purported to be shaped by coaches’ and athletes’ self-perceptions (e.g., I trust my coach/athlete) and metaperceptions (e.g., My coach/athlete trusts me) of closeness, commitment, and complementarity (3Cs). The development of the Coach–Athlete Relationship Questionnaire (CART-Q; S. Jowett & N. Ntoumanis, 2004) has enabled the assessment of coaches’ and athletes’ self-perceptions of the relationship as defined by the 3Cs. The author conducted 2 studies to examine the factor structure and criterion-related validity of the CART-Q when its items are worded to express metaperceptions. In the 1st study, confirmatory factor analyses employing a sample of athletes (n = 201) supported the validity of a 3-dimensional model in which the factors were separate but correlated for metacloseness, metacommitment, and metacomplementarity. The 2nd study provided further evidence of validity when the 3 factors were examined relative to criterion variables with 2 independent samples: athletes (n = 189) and coaches (n = 138). These results highlight that the conceptual model from which the CART-Q was developed captures the relationship quality through athletes’ and coaches’ feelings (closeness), thoughts (commitment), and behaviors (complementarity). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Buboltz Walter C. Jr.; Miller Matthew; Williams David J. 《Canadian Metallurgical Quarterly》1999,46(4):496
A content analysis of the research published in the Joumal of Counseling Psychology (JCP) was conducted for a 26-year period (1973–1998). A total of 2,027 articles were classified into 14 substantive content categories. Frequency distributions were used to identify the most frequently published authors and institutional affiliations, as well as the gender and ethnic characteristics reported. The principal areas of research activity and publication in the JCP were process only, process and outcome, vocational behavior research, and the development and evaluation of tests and measures. These 4 categories accounted for 55.2% of the articles examined. Typical reported samples contained college students of both genders. This content analysis revealed that over this 26-year time span, the research reported in the JCP has remained consistent with the mission statement of the journal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
可溶高分子负载钯催化剂对于硝基苯加氢反应催化性能的研究 总被引:3,自引:1,他引:2
以醇或水溶性高分子(聚乙烯吡咯烷酮,PVP;乙基纤维素,EC;聚乙烯醇,PVA;羧甲基纤维素钠,CMCNa)为载体,制备了四种可溶高分子负载钯催化剂。无机碱的存在对反应呈明显的加速效应。在少量K2CO3存在下,EC-PdCl2和PVP-PdCl2对于硝基苯的催化加氢具有非常高的活性,最高活性>230molH2/molPd·min,即大于5150mlH2/mmolPd·min,该数值是已知文献报道的最好结果。详细考察了各种碱、K2CO3用量、溶剂以及反应温度对PVP-PdCl2催化硝基苯加氢性能的影响。 相似文献
995.
Anoosh Shamsabadi Kyle M. Rollins Mike Kapuskar 《Canadian Metallurgical Quarterly》2007,133(6):707-720
Current seismic design of bridges is based on a displacement performance philosophy using nonlinear static pushover analysis. This type of bridge design necessitates that the geotechnical engineer predict the resistance of the abutment backfill soils, which is inherently nonlinear with respect to the displacement between soil backfill and the bridge structure. This paper employs limit-equilibrium methods using mobilized logarithmic-spiral failure surfaces coupled with a modified hyperbolic soil stress–strain behavior (LSH model) to estimate abutment nonlinear force-displacement capacity as a function of wall displacement and soil backfill properties. The calculated force-displacement capacity is validated against the results from eight field experiments conducted on various typical structure backfills. Using LSH and experimental data, a simple hyperbolic force-displacement (HFD) equation is developed that can provide the same results using only the backfill soil stiffness and ultimate soil capacity. HFD is compatible with current CALTRANS practice in regard to the seismic design of bridge abutments. The LSH and HFD models are powerful and effective tools for practicing engineers to produce realistic bridge response for performance-based bridge design. 相似文献
996.
Soft robotics is important in the next generation of robots because of the rapidly increasing need for robotics in biomedical applications and the advantages of providing a soft interface for interaction with the physical environment in service robots and other applications. It is indispensable to understand the fundamental behavior of such contact interface, typically viscoelastic, in order to accurately predict the actual elastic and temporal responses of the contact and to successfully control it. Viscoelasticity is a phenomenon of time-dependent strain and/or stress in soft materials. It is therefore important to model such behavior and to study the effects of such time-dependent strain and stress on stability and behavior at the contact interface. The contribution of this paper is the introduction of a novel latency model, which is a nonlinear model with differential equations that govern viscoelastic materials. Latency model describes various features of viscoelastic materials, such as stress relaxation and strain creep. The theoretical modeling was supported by experimental results in which we found two types of relaxation. Type I relaxation is well documented in existing literature but Type II relaxation has not been elaborated previously with the physical insights provided in this paper. The proposed theory can unify both types of time-dependent relaxation responses for modeling, sensing, and interpretation of viscoelastic contact interface. 相似文献
997.
998.
《Advanced Robotics》2013,27(4):405-428
Robots designed to interact socially with people require reliable estimates of human position and motion. Additional pose data such as body orientation may enable a robot to interact more effectively by providing a basis for inferring contextual social information such as people's intentions and relationships. To this end, we have developed a system for simultaneously tracking the position and body orientation of many people, using a network of laser range finders mounted at torso height. An individual particle filter is used to track the position and velocity of each human, and a parametric shape model representing the person's cross-sectional contour is fit to the observed data at each step. We demonstrate the system's tracking accuracy quantitatively in laboratory trials and we present results from a field experiment observing subjects walking through the lobby of a building. The results show that our method can closely track torso and arm movements, even with noisy and incomplete sensor data, and we present examples of social information observable from this orientation and positioning information that may be useful for social robots. 相似文献
999.
《Advanced Robotics》2013,27(6-7):657-687
In this paper the kinematic and Jacobian analysis of a macro–micro parallel manipulator is studied in detail. The manipulator architecture is a simplified planar version adopted from the structure of the Large Adaptive Reflector (LAR), the Canadian design of the next generation of giant radio telescopes. This structure is composed of two parallel and redundantly actuated manipulators at the macro and micro level, which both are cable-driven. Inverse and forward kinematic analysis of this structure is presented in this paper. Furthermore, the Jacobian matrices of the manipulator at the macro and micro level are derived, and a thorough singularity and sensitivity analysis of the system is presented. The kinematic and Jacobian analysis of the macro–micro structure is extremely important to optimally design the geometry and characteristics of the LAR structure. The optimal location of the base and moving platform attachment points in both macro and micro manipulators, singularity avoidance of the system in nominal and extreme maneuvers, and geometries that result in high dexterity measures in the design are among the few characteristics that can be further investigated from the results reported in this paper. Furthermore, the availability of the extra degrees of freedom in a macro–micro structure can result in higher dexterity provided that this redundancy is properly utilized. In this paper, this redundancy is used to generate an optimal trajectory for the macro–micro manipulator, in which the Jacobian matrices derived in this analysis are used in a quadratic programming approach to minimize performance indices like minimal micro manipulator motion or singularity avoidance criterion. 相似文献
1000.
F. Alonso-Martín 《控制论与系统》2013,44(4):215-245
Human–robot interaction (HRI) 1 is one of the main fields in the study and research of robotics. Within this field, dialogue systems and interaction by voice play an important role. When speaking about human–robot natural dialogue we assume that the robot has the capability to accurately recognize what the human wants to transmit verbally and even its semantic meaning, but this is not always achieved. In this article we describe the steps and requirements that we went through in order to endow the personal social robot Maggie, developed at the University Carlos III of Madrid, with the capability of understanding the natural language spoken by any human. We have analyzed the different possibilities offered by current software/hardware alternatives by testing them in real environments. We have obtained accurate data related to the speech recognition capabilities in different environments, using the most modern audio acquisition systems and analyzing not so typical parameters such as user age, gender, intonation, volume, and language. Finally, we propose a new model to classify recognition results as accepted or rejected, based on a second automatic speech recognition (ASR) opinion. This new approach takes into account the precalculated success rate in noise intervals for each recognition framework, decreasing the rate of false positives and false negatives. 相似文献