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101.
Hanan Samet 《Software》1981,11(10):1053-1069
Experience with a program to convert from LISP 1.6 to INTERLISP is described. The conversion program was designed with two goals in mind. First, it had to be capable of being executed in either of the languages's environments and it had to yield identical results. Second, the speed of the converted program was to be approximately the same as the original program. This meant that the conversion process must be completed prior to execution of the converted program. The various constraints and considerations imposed by these goals are examined. In addition, aside from problems in finding INTERLISP analogs for various LISP 1.6 constructs, careful consideration must also be paid to input/output functions, escape characters, global variables, representation of numbers and different string implementations. 相似文献
102.
Mesfer Al Duhayyim Jaber S. Alzahrani Hanan Abdullah Mengash Mrim M. Alnfiai Radwa Marzouk Gouse Pasha Mohammed Mohammed Rizwanullah Amgad Atta Abdelmageed 《计算机系统科学与工程》2023,46(2):1471-1485
The Internet of Things (IoT) environment plays a crucial role in the design of smart environments. Security and privacy are the major challenging problems that exist in the design of IoT-enabled real-time environments. Security susceptibilities in IoT-based systems pose security threats which affect smart environment applications. Intrusion detection systems (IDS) can be used for IoT environments to mitigate IoT-related security attacks which use few security vulnerabilities. This paper introduces a modified garden balsan optimization-based machine learning model for intrusion detection (MGBO-MLID) in the IoT cloud environment. The presented MGBO-MLID technique focuses on the identification and classification of intrusions in the IoT cloud atmosphere. Initially, the presented MGBO-MLID model applies min-max normalization that can be utilized for scaling the features in a uniform format. In addition, the MGBO-MLID model exploits the MGBO algorithm to choose the optimal subset of features. Moreover, the attention-based bidirectional long short-term (ABiLSTM) method can be utilized for the detection and classification of intrusions. At the final level, the Aquila optimization (AO) algorithm is applied as a hyperparameter optimizer to fine-tune the ABiLSTM methods. The experimental validation of the MGBO-MLID method is tested using a benchmark dataset. The extensive comparative study reported the betterment of the MGBO-MLID algorithm over recent approaches. 相似文献
103.
Hassan Chizari Majid Hosseini Shaharuddin Salleh Shukor Abd Razak Abdul Hanan Abdullah 《The Journal of supercomputing》2012,59(2):744-761
MultiPoint Relay (MPR) selection algorithm is a flooding technique for propagating a broadcast message inside an ad-hoc network
which reduces the number of unnecessary broadcast messages in order to save more energy in the network, minimize the number
of packet collisions, and speed up the propagation time. In this paper, we demonstrate that MPR selection is an application
of Set Covering Problem (SCP). A few optimization methods are developed in this work to find the optimum solution including
Simulated Annealing (SA), Tabu Search (TS), Genetic Algorithm (GA), and a new greedy algorithm. Extensive simulations are
set up to evaluate the developed methods. The new algorithm is named Energy eFficient MPR or EF-MPR in short. The simulation
results show that EF-MPR can reduce the number of MPR nodes up to 19%. Moreover, EF-MPR algorithm reduces the power-consumption
of network up to 12% and speed up the propagation time by 9%. 相似文献
104.
Wireless Networks - The evolving Fifth generation (5G) cellular wireless networks are envisioned to provide higher data rates, lower end-to-end latency, and lower energy consumption for devices. In... 相似文献
105.
Ronen A Gershon P Drobiner H Rabinovich A Bar-Hamburger R Mechoulam R Cassuto Y Shinar D 《Accident; analysis and prevention》2008,40(3):926-934
BACKGROUND: The effects of marijuana or THC on driving has been tested in several studies, but usually not in conjunction with physiological and subjective responses and not in comparison to alcohol effects on all three types of measures. OBJECTIVE: To assess the effects of two dosages of THC relative to alcohol on driving performance, physiological strain, and subjective feelings. METHOD: We tested the subjective feelings and driving abilities after placebo, smoking two dosages of THC (13 mg and 17 mg), drinking (0.05% BAC) and 24 h after smoking the high dose THC cigarette, while monitoring physiological activity of the drugs by heart rate. Fourteen healthy students, all recreational marijuana users, participated in the study. RESULTS: Both levels of THC cigarettes significantly affected the subjects in a dose-dependent manner. The moderate dose of alcohol and the low THC dose were equally detrimental to some of the driving abilities, with some differences between the two drugs. THC primarily caused elevation in physical effort and physical discomfort during the drive while alcohol tended to affect sleepiness level. After THC administration, subjects drove significantly slower than in the control condition, while after alcohol ingestion, subjects drove significantly faster than in the control condition. No THC effects were observed after 24 h on any of the measures. 相似文献
106.
Three analytical techniques (ASTM, FNAA and INAA) have been used to determine the major elemental composition, the percentage concentrations of Si, Fe, Al, as well as the concentrations of the trace elements Ca, K, Cl, Mg, Na and Ti of coals from seven major deposits in Nigeria. The results show that Nigerian coals are of weak or noncoking grades with low sulphur (0.52-2.04%) and high hydrogen (3.7-6.60%) contents. The coals possess properties which make them suitable feedstocks in gasification processes. They may also be used as blends with coking coals for sintering. Their potentials in the production of form coke in metallurgical and domestic applications, in addition to their suitability as thermal coals for electricity generation and steam raising in industries, provide incentives for their utilization. 相似文献
107.
We consider preemptive online and semi-online scheduling of unit jobs on two uniformly related machines. Jobs are presented one by one to an algorithm, and each job has a rejection penalty associated with it. A new job can either be rejected, in which case the algorithm pays its rejection penalty, or it can be scheduled preemptively on the machines, in which case it may increase the maximum completion time of any machine in the schedule, also known as the makespan of the constructed schedule. The objective is to minimize the sum of the makespan of the schedule of all accepted jobs and the total penalty of all rejected jobs. We study two versions of the problem. The first one is the online problem where the jobs arrive unsorted, and the second variant is the semi-online case, where the jobs arrive sorted by a non-increasing order of penalties. We also show that the variant where the jobs arrive sorted by a non-decreasing order of penalties is equivalent to the unsorted one. We design optimal online algorithms for both cases. These algorithms have smaller competitive ratios than the optimal competitive ratio for the more general problem with arbitrary processing times (except for the case of identical machines), but larger competitive ratios than the optimal competitive ratio for preemptive scheduling of unit jobs without rejection. 相似文献
108.
The combination of biopolymer with a bioactive component takes advantage of the osteoconductivity and osteoinductivity properties. The studies on composites containing hydroxyapatite (HA), demineralized bone matrix (DBM) fillers and chitosan biopolymer are still conducted. In the present study, the bioactive fillers were loaded onto p(HEMA‐MMA) grafted chitosan copolymer to produce a novel biocomposites having osteoinductive and osteoconductive properties. The produced composites were assessed by TGA, XRD, FTIR, and SEM techniques to prove the interaction between both matrices. In vitro behavior of these composites was performed in SBF to verify the formation of apatite layer onto their surfaces and its enhancement. The results confirmed the formation of thick apatite layer containing carbonate ions onto the surface of biocomposites especially these containing HA‐DBM mixture and pMMA having bone cement formation in their structure. These a novel biocomposites have unique bioactivity properties can be applied in bone implants and tissue engineering applications as scaffolds in future. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献
109.
The heterogeneous catalyst of V2 O 5/SiO2 was prepared and characterized with Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy. XRD of the silicon dioxide used reveals the amorphous nature while the spectrum of the prepared catalyst shows sharp intense peaks at about (20.2, 26.1, 31.0 and 47.3°) and less intense sharp peaks at about (51.1, 55.2, 57.1 and 60.4°) indicating formation of a crystalline phase with orthorhombic geometry. The FTIR spectra of the catalyst showed characteristic vibration stretching bands of V ?O at their specified position. An efficient and facile approach for the synthesis of bis(indolyl)methanes through a catalytic one pot reaction. Indole and aromatic aldehydes were stirred in the presence of a catalytic amount of the prepared and characterized heterogeneous catalyst V2 O 5/SiO2 at 50°C under solvent free condition. This procedure has advantages in competition with the previously reported methods, in terms of high yield, green catalyst, mild reaction condition, simple procedure, lack of toxicity, low cost, and simplicity of workup. 相似文献