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101.
Hormones excreted in animal waste have been measured in surface and groundwater associated with manure that is applied to the land surface. Limited studies have been done on the fate and transport of androgenic hormones in soils. In this study, batch and column experiments were used to identify the fate and transport of radiolabeled [14C] testosterone in agricultural soils. The batch results indicated that aqueous-phase concentrations decreased for the first 5 h and then appeared to increase through time. The first-order sorption kinetics ranged from 0.08 to 0.640 h(-1) for the first 5 h. Beyond 5 h the increase in aqueous 14C could have been caused by desorption of testosterone back into the aqueous phase. However, metabolites were also produced beyond 5 h and would have likely resulted in the increase in aqueous 14C by sorption site competition and/or by lower sorption affinity. There were weak correlations of sorption with soil particle size, organic matter, and specific surface area. Testosterone was the dominant compound present in the soil column effluents, and a fully kinetic-sorption, chemical nonequilibrium model was used to describe the data. Column experiment sorption estimates were lower than the batch, which resulted from rate-limiting sorption due to the advective transport. The column degradation coefficients (0.404-0.600 h(-1)) were generally higher than values reported in the literature for 17beta-estradiol. Although it was found that testosterone degraded more readily than 17beta-estradiol, it appeared to have a greater potential to migrate in the soil because it was not as strongly sorbed. This study underlined the importance of the simultaneous transformation and sorption processes in the transport of hormones through soils. 相似文献
102.
Robert Sim Pantelis Elinas James J. Little 《International Journal of Computer Vision》2007,74(3):303-318
With recent advances in real-time implementations of filters for solving the simultaneous localization and mapping (SLAM)
problem in the range-sensing domain, attention has shifted to implementing SLAM solutions using vision-based sensing. This
paper presents and analyses different models of the Rao-Blackwellised particle filter (RBPF) for vision-based SLAM within
a comprehensive application architecture. The main contributions of our work are the introduction of a new robot motion model
utilizing structure from motion (SFM) methods and a novel mixture proposal distribution that combines local and global pose
estimation. In addition, we compare these under a wide variety of operating modalities, including monocular sensing and the
standard odometry-based methods. We also present a detailed study of the RBPF for SLAM, addressing issues in achieving real-time,
robust and numerically reliable filter behavior. Finally, we present experimental results illustrating the improved accuracy
of our proposed models and the efficiency and scalability of our implementation. 相似文献
103.
Yong-Duck Chung Kwang-Seong Choi Jae-Sik Sim Hyun-Kyu Yu Jeha Kim 《Lightwave Technology, Journal of》2007,25(11):3407-3412
We developed an analog optical system-on-package (SoP) transmitter for a 60-GHz-band radio-over-fiber (RoF) link. The SoP transmitter consisted of an electroabsorption modulator, radio frequency amplifiers, and a bandpass filter. The 60-GHz RoF wireless link was prepared to measure the performance of the SoP transmitter. The transmission characteristics of 64-quadrature amplitude modulation (64-QAM) data of the 60-GHz RoF wireless link, including the SoP transmitter, were investigated by measuring the error vector magnitude (EVM) and signal-to-noise ratio (SNR) with a baseband frequency. The EVM of the 60-GHz RoF wireless link was between 2.25% and 2.80%, and the SNR was between 27.36 and 29.31 dB from 140 and 770 MHz, at input baseband power of -9 dBm. The noise figure had the minimum of 8.44 dB at 500 MHz. We successfully transmitted digital community antenna television (CATV) system signals through the 60-GHz RoF wireless link, including the SoP transmitter. Digital CATV signals of 86 channels could be transmitted through the 60-GHz RoF wireless link, and the total throughput was found to be 2.61 Gb/s. 相似文献
104.
Service composition in multi-Cloud environments must coordinate self-interested participants, automate service selection, (re)configure distributed services, and deal with incomplete information about Cloud providers and their services. This work proposes an agent-based approach to compose services in multi-Cloud environments for different types of Cloud services: one-time virtualized services, e.g., processing a rendering job, persistent virtualized services, e.g., infrastructure-as-a-service scenarios, vertical services, e.g., integrating homogenous services, and horizontal services, e.g., integrating heterogeneous services. Agents are endowed with a semi-recursive contract net protocol and service capability tables (information catalogs about Cloud participants) to compose services based on consumer requirements. Empirical results obtained from an agent-based testbed show that agents in this work can: successfully compose services to satisfy service requirements, autonomously select services based on dynamic fees, effectively cope with constantly changing consumers’ service needs that trigger updates, and compose services in multiple Clouds even with incomplete information about Cloud participants. 相似文献
105.
An augmented EDA with dynamic diversity control and local neighborhood search for coevolution of optimal negotiation strategies 总被引:2,自引:2,他引:0
In this paper, we present an estimation of distribution algorithm (EDA) augmented with enhanced dynamic diversity controlling and local improvement methods to solve competitive coevolution problems for agent-based automated negotiations. Since optimal negotiation strategies ensure that interacting agents negotiate optimally, finding such strategies—particularly, for the agents having incomplete information about their opponents—is an important and challenging issue to support agent-based automated negotiation systems. To address this issue, we consider the problem of finding optimal negotiation strategies for a bilateral negotiation between self-interested agents with incomplete information through an EDA-based coevolution mechanism. Due to the competitive nature of the agents, EDAs should be able to deal with competitive coevolution based on two asymmetric populations each consisting of self-interested agents. However, finding optimal negotiation solutions via coevolutionary learning using conventional EDAs is difficult because the EDAs suffer from premature convergence and their search capability deteriorates during coevolution. To solve these problems, even though we have previously devised the dynamic diversity controlling EDA (D2C-EDA), which is mainly characterized by a diversification and refinement (DR) procedure, D2C-EDA suffers from the population reinitialization problem that leads to a computational overhead. To reduce the computational overhead and to achieve further improvements in terms of solution accuracy, we have devised an improved D2C-EDA (ID2C-EDA) by adopting an enhanced DR procedure and a local neighborhood search (LNS) method. Favorable empirical results support the effectiveness of the proposed ID2C-EDA compared to conventional and the other proposed EDAs. Furthermore, ID2C-EDA finds solutions very close to the optimum. 相似文献
106.
107.
Yeom Hong-Gi Park Seung-Min Park Junheong Sim Kwee-Bo 《International Journal of Control, Automation and Systems》2011,9(3):595-600
To improve the performance of classification algorithms, we proposed a new varianceconsidered machine (VCM) classification
algorithm in a previous study. The study showed theoretically that VCMs have lower error probabilities than SVMs. The purpose
of this paper is to experimentally demonstrate the superiority of VCMs. Therefore, we verified our proposal with several case
experiments using data following a Gaussian distribution with different variances and prior probabilities. To estimate performance,
the experiment for each case was executed 1000 times and the error rates were averaged for accuracy. The data of each experiment
have different distances between means of data, and different ratios between training data and testing data. Thus, we proved
that the error rate of VCMs is lower than the error rate of SVMs, although their performances were not similar in each case.
Consequently, we expect that VCMs will be applied to a variety fields. 相似文献
108.
Zhiyuan Chen Le Dinh Van Khoa Ee Na Teoh Amril Nazir Ettikan Kandasamy Karuppiah Kim Sim Lam 《Knowledge and Information Systems》2018,57(2):245-285
Money laundering has been affecting the global economy for many years. Large sums of money are laundered every year, posing a threat to the global economy and its security. Money laundering encompasses illegal activities that are used to make illegally acquired funds appear legal and legitimate. This paper aims to provide a comprehensive survey of machine learning algorithms and methods applied to detect suspicious transactions. In particular, solutions of anti-money laundering typologies, link analysis, behavioural modelling, risk scoring, anomaly detection, and geographic capability have been identified and analysed. Key steps of data preparation, data transformation, and data analytics techniques have been discussed; existing machine learning algorithms and methods described in the literature have been categorised, summarised, and compared. Finally, what techniques were lacking or under-addressed in the existing research has been elaborated with the purpose of pinpointing future research directions. 相似文献
109.
Sejoon Yoon Huijun Sim Jun Seok Kim Suk-In Hong 《Korean Journal of Chemical Engineering》2009,26(5):1323-1327
In this paper the internal contactor is a newly developed device for the primary recovery of protein from crude feedstock.
Ion exchanges (DEAE-Streamline) are confined inside the internal contactor in a stirred tank. Interactions between the ion
exchange in the internal contactor and protein (BSA) in yeast suspension have been studied. For better performance, two strategies
are considered: to determine the ion conductivity of a simulated yeast suspension, and to select the optimum process time
for adsorption. In this system, advantages of both batch adsorption and expanded bed adsorption were obtained. Furthermore,
in denser cell concentration (50 g/L) where EBA cannot be operated, the primary recovery was carried out in 1–2 hr. The efficiency
of yield is higher than 80% in this condition. 相似文献
110.
Ki-Whan Song Yong Kyu Lee Jae Sung Sim Hoon Jeoung Jong Duk Lee Byung-Gook Park You Seung Jin Young-Wug Kim 《Electron Devices, IEEE Transactions on》2005,52(8):1845-1850
We have developed an integration technology for the single electron transistor (SET)/CMOS hybrid systems. SET and CMOS transistors can be optimized without any possible degradation due to mixing dissimilar devices by adopting just one extra mask step for the separate gate oxidation (SGOX). We have confirmed that discrete devices show ideal characteristics required for the SET/CMOS hybrid systems. An SET shows obvious Coulomb oscillations with a 200-mV period and CMOS transistors show high voltage gain. Based on the hybrid process, new hybrid circuits, called periodic multiband filters, are proposed and successfully implemented. The new filter is designed to perform a filtering operation according to the periodic multiple blocking bands of which a period is originated from the SET. Such a novel function was implemented efficiently with a few transistors by making full use of the periodic nature of SET characteristics. 相似文献