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91.
Undergraduate engineering programs in fourteen countries are surveyed to determine the status of engineering education outside the United States and to analyze the implications for the ideal engineering program of the future here in the United States. The items surveyed include the number of years required to obtain an engineering degree, title of the engineering degree, high school preparation for engineering programs, cost of education, completion rates for engineering degrees, entrance requirements, mathematical requirements, and support for laboratory work. The most notable aspects of engineering education outside the United States are:
  • ? Stronger high school preparation and requirements in mathematics and science
  • ? Longer period of time required for an engineering degree
  • ? Advanced level of mathematics required in engineering programs
  • ? Low cost of education
It appears that in most countries engineering education is more intense and rigorous than in the United States. In formulating the ideal engineering program of the future we must be sensitive to competing programs in the rest of the world.  相似文献   
92.
This paper presents a comparison study of the computational complexity of the general job shop protocol and the more structured flow line protocol in a flexible manufacturing system. It is shown that the representative problem of finding resource invariants is NP-complete in the case of the job shop, while in the flow line case it admits a closed form solution. The importance of correctly selecting part flow and job routing protocols in flexible manufacturing systems to reduce complexity is thereby conclusively demonstrated  相似文献   
93.
We compared two gastrin radioimmunoassay kits ("Immutope" kit, Squibb & Co.; "Gastrin R.I.A." kit, Schwarz/Mann) to the conventional gastrin radioimmunoassay of Yalow and Berson [Gastroenterology 58, 1 (1970)] as run by us and by a second reference laboratory. Although both kits were found to effectively discriminate above-normal and normal values for serum gastrin, they significantly underestimated very high values (greater than 1500 ng/liter). The Schwarz/Mann kit clearly had a superior quality label (lower nonspecific binding and higher specific activity) and a shorter incubation time. However, the 90-min incubation period cited for their kit caused overestimation of gastrin values in the lower range (5-300 ng/liter), which could be corrected by prolonging the incubation to 24 h. The Squibb antibody had fairly good cross reactivity to all gastrin species tested; the Schwarz/Mann antibody had poor affinity for natural human gastrin G34-II. Good correspondence was found for sera run by both reference laboratories (y = 0.96x + 10, r = 0.997), and values obtained with the Schwarz/Mann kit correlated best (+ 0.815) with those from the conventional radioimmunoassay procedure.  相似文献   
94.
Abdallah OY 《Meat science》1983,8(4):301-315
The left sides of the carcasses of twelve Egyptian buffalo, nine half Friesian (♂ Friesian x ♀ Egyptian Baladi) and nine three-quarter Friesian (♂ x ♀ half-Friesian) bulls, serially slaughtered between 161 and 560 kg for buffaloes and between 176 and 448 kg for cattle, were used to describe the growth and distribution of individual muscles and muscle groups.

Genotype-group differences in the relative rate of growth were not significant in 85 of 89 muscles and in 8 of 9 muscle groups. The pooled within-group growth coefficients of individual muscles revealed different increasing growth gradients, i.e. disto-proximal in both limbs, mediolateral in the proximal pelvic limb, from elbow flexors to shoulder flexors in the proximal thoracic limb, caudo-cranial in the trunk and from hypaxial to epaxial muscles around the spinal column. The relative growth was lowest in the distal part of the limbs and highest in the anterior part of the carcass (SMG 7 and 8), with the loin and abdominal muscle groups growing at a rate similar to that of the total muscle. The neck and thorax muscle group grew at a higher rate in Friesian crosses than in buffaloes.

Genotype-group differences in the weight of each muscle relative to total side muscle (TSM) were significant in 50 of 89 muscles. Of the 50 muscles (constituting around 59% of TSM), 24 (approximately 44% of TSM) were from the expensive muscle groups. As compared with the most different Friesian cross (base = 100) at equal TSM, buffaloes had higher weight of muscle in the hindlimb (107·5% proximally; 106·3% distally) and forelimb (120·0% proximally: 104·6% distally) and significantly less weight of the muscle groups forming the abdominal wall (79·8%) and connecting the forelimb to the thorax (89·1%) and to the neck (90·7%). The weight of the combined expensive groups was significantly greater in buffaloes than in cattle (maximum difference = 1·8 kg) with a tendency for buffaloes to have relatively less of the tender muscles surrounding the spinal column.  相似文献   

95.
Histories of deliveries and development records of 44 newborns with penumopathies who had died on the first days of life in the presence of phenomena of the syndrome of respiratory disorder were analysed and the newborns' lungs were morphologically investigated. The investigation made it possible to single out the following forms of pneumopathy in newborns: edematous-hemorrhagic, hyaline, atelectatic, aspirated, and mixed. In the majority of cases the syndrome of respiratory disorder was a sequela of hypoxia of the intrauterine origin which continued during the first hours and days of life after birth. Such "primary asphyxia" may lead to the development of pneumopathy in a neonate. On the other hand, "secondary asphyxia" in many cases represent sequelae of penumopathy destructural and functional immaturity of the pulmonary tissue, hypoxia, a higher permeability of vessels of the microcirculatory bed, spasm of small pulmonary arteris contributed considerably to the development of penumopathies.  相似文献   
96.
Distributed machining control and monitoring using smart sensors/actuators   总被引:1,自引:1,他引:1  
The study of smart sensors and actuators led, during the past few years, to the development of facilities which improve traditional sensors and actuators in a necessary way to automate production systems. In another context, many studies have been carried out aimed at defining a decisional structure for production activity control and the increasing need of reactivity leads to the autonomization of decisional levels close to the operational system. We study in this paper the natural convergence between these two approaches and we propose an integration architecture, dealing with machine tool and machining control, that enables the exploitation of distributed smart sensors and actuators in the decisional system.  相似文献   
97.
In this paper, we present the concept of work compatibility as an integrated work design criterion that simultaneously improves human health and safety, productivity, and work quality in manufacturing systems. In this respect, we have modeled work compatibility as a work design parameter that mathematically integrates the energizing (i.e., system resources) and the demand (i.e., system requirements) forces in the work system. A mathematical equation has been derived for the work compatibility matrix. Furthermore, an operating zone has been developed in which there is a region of optimality for the employee to function on practical grounds with a good degree of efficiency and sustainability. An application example is provided to demonstrate the potential of work compatibility to improve productivity and quality along with improvement in worker safety and health. © 2004 Wiley Periodicals, Inc. Hum Factors Man 14: 379–402, 2004.  相似文献   
98.
99.
In light of current calls by medical professionals to confront the global issue of obesity and related illnesses, we developed a mobile application called STEP UP that monitors physical activity and provides data that can be easily shared within a social network. We then conducted an exploratory, theoretical study based on the theory of reasoned action (TRA) followed by an experimental trial and user study. The purpose of the studies was to explore the effect of persuasive technology on physical activity behavior and to investigate its effectiveness in motivating users to use the technology to be more physically active. The application was found to have a positive effect on the participants and their level of physical activity. They enjoyed using the application and were motivated to walk more, especially when enabled to share their step counts with their friends. The social component of the application clearly enhanced users’ walking experience, as the atmosphere of friendly competition motivated them to walk more. Based on user responses, we conclude that a further enhanced application that includes chat functionality may be even more successful in supporting increased physical activity and thus healthier lifestyle.  相似文献   
100.
Manganese-cobalt ferrite powders (Mn x Co1?x Fe2O4 with x varying from 0.0 to?0.6) have been produced by glycothermal process from pure metal chlorides. Single phase cubic spinel structure and nanophase structure of the as-synthesized samples were confirmed by X-ray diffraction (XRD) and by transmission electron microscope (TEM). The results show that the produced powders have grain sizes in the range 7 to 13?nm. Fe-57 M?ssbauer spectra for as-synthesized and for annealed samples at 700???C (in Ar atmosphere for 1?hour) are found to be similar. No significant changes in the spectra are observed across the composition range studied. The variations of grain sizes, lattice parameters, and M?ssbauer parameters as a function of composition have also been investigated. Bulk samples in the form of pellets were also produced from the as-synthesized compounds for resistivity measurements. The temperature dependence of the electrical resistivity for the samples sintered at 1050???C were studied using the four-probe method, from room temperature to about 110???C in a PID controlled oven. Two possible mechanisms for resistivity involving T ?1/2 and T ?1 dependences are investigated.  相似文献   
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