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41.
BACKGROUND AND OBJECTIVE: The authors conducted a randomized, prospective, and controlled clinical and transmission electron microscopic study to investigate the possible role of cyclosporine in trabeculectomy as an antimetabolite agent. PATIENTS AND METHODS: Twelve patients underwent trabeculectomy with topical cyclosporine and another 12 patients had trabeculectomy without cyclosporine. RESULTS: There was a statistically significant decrease in the postoperative intraocular pressure (P < .05) and in the number of medications needed postoperatively (P < .01) in the cyclosporine group. There were no significant complications in either group. Transmission electron microscopic examinations of the excised trabecular scleral tissue showed that cyclosporine caused inhibition of fibroblasts and led to a disruption in collagen organization at the level of the surgical dissection. Middle scleral layers were generally not affected except in some cyclosporine-treated eyes, which showed only a mild cytopathic effect. CONCLUSION: This study showed that topical cyclosporine was safe and effective for use as an antimetabolite in trabeculectomy. Further studies are needed to substantiate the adjuvant role of cyclosporine in glaucoma filtering operations.  相似文献   
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The visual inspection of parts as they progress through die manufacturing process is an important task in all industries. Visual inspection, when performed by humans is a tedious task and is prone to error. This is precisely what makes it a good candidate for automation. Although computer vision systems have been around for over 30 years, die industrial applications of vision systems have become practical only in die last decade. Image processing and pattern recognition algorithms used in industrial vision systems are built upon a broad body of knowledge in vision research. But the use of computer vision systems in quality control has been limited to replicating die visual inspection tasks as they would be performed by a human operator. It is die contention of this study that when computerized inspection is employed, quality control inspection plans suitable for computerized inspection should also be employed to assure cost-effectiveness.

We study a simple gauging inspection task and propose a quality control plan that exploits die characteristics of computer vision systems in order to improve cost-effectiveness.  相似文献   
44.
Grundlagen mathematischer Modelle zur Erfassung des Spannungszustandes im Winderhitzermantel nach der Schalentheorie. Annahmen. Vereinfachungen für den Fall, daß der Winderhitzermantel isotherm, homogen und isotrop ist und daß die mechanische Belastung radialsymmetrisch erfolgt. Angabe von analytischen Lösungen für einige Fälle. Hinweis auf die weitere Entwicklung dieser Modelle des Spannungszustandes.  相似文献   
45.
This paper reviews the work carried out by the Industrial Research Laboratory in cooperation with the Machine Tool Laboratory at the University of Florida to design and build a Supervision System for Machining Centers. The objective of the Supervision System is to perform three main functions: Chatter Detection and Control, Cutter Breakage Detection, and Adaptive Feed Control [1], [2]. Our contribution to this project consists of providing low-level intelligence to the machine tool controller and high-level user-friendly operator interface (monitoring screen), so that the machine tool, as a unit will be more robust and efficient, thus more economical to operate. A simple PC based embedded control system for chatter and tool breakage detection as well as a user-friendly operator interface unit will be discussed.  相似文献   
46.
This paper presents a continuous time sliding mode controller (SMC) design to deal with the problem of motion synchronization in dual spindle servo systems. Synchronization error is defined as the differential position error between the two servo drives that follow identical reference motion trajectory. Proposed SMC controller penalizes three error states; namely individual axis tracking errors and the synchronization error for accurate synchronization. The control law is derived from Lyapunov energy function without switching condition. The controller shows robust motion synchronization against disturbances and parameter variations. Proposed SMC control is implemented in conventional double-sided machining operation.  相似文献   
47.
The survival curves of Escherichia coli and Listeria innocua inactivated by high hydrostatic pressure (HHP) were obtained at room temperature (∼22 °C) and at five pressure levels (400, 450, 500, 550 and 600 MPa) in whole milk. These curves were described by the Weibull model and parameters of this model were reduced from two to one with slight loss of goodness-of-fit. The logarithm of the time constant parameter (δ) of the reduced Weibull model was described with respect to high pressure (P). This approach can be used to define a z p value analogous to the modeling of the classical D value (increase in pressure that results in one log unit decrease of δ values). The development of accurate survival models under high pressure, as presented here, can be very beneficial to food industry for designing, evaluating and optimizing HHP processes as a new preservation technology.  相似文献   
48.
This paper presents a new active vibration control strategy to mitigate high frequency regenerative chatter vibrations using machine tool feed drives. Rather than modal damping, proposed approach aims to control regenerative process dynamics to shape the Stability Lobe diagram (SLD) and attain higher material removal rates. The controller is designed as a feedback filter whose parameters are optimized to compensate regeneration. The proposed strategy is applied to actively control orthogonal (plunge) turning dynamics where >2.5 [kHz] chatter vibrations are suppressed by a fast tool servo (FTS) drive system. Stability lobes are shaped locally to reach up to 4x higher material removal rates.  相似文献   
49.
Escherichia coli cells in peptone water were pressurized at 300 MPa at ambient temperature with no holding time (pulse series) and with a total holding duration of 300 s for single- (300 s × 1 pulse) and multi-pulsed (150 s × 2 pulses, 100 s × 3 pulses, 75 s × 4 pulses, 60 s × 5 pulses, 50 s × 6 pulses and 30 s × 10 pulses) high hydrostatic pressure (HHP) treatments. Multi-pulsed HHP treatment with no holding time indicated that as the pulse number increased the number of inactivated and injured cells also increased. Holding time had significant effect on the inactivation of E. coli. There was low inactivation difference between single- and multi-pulsed HHP treatments with holding time. Escherichia coli cells showed at least 1.6 log10 more reduction on selective medium than the non-selective medium indicating that more than 95 % of the survivors severely injured for both single- and multi-pulsed treatments with holding time. Although the inactivation difference was low between single- and multi-pulsed HHP treatments, storage at 4 °C revealed that there was less recovery from injury for multi-pulsed HHP treatment.  相似文献   
50.
The purpose of this research is to investigate the drying kinetics and determine the suitable drying method of prina, which is obtained after pressing of olives in olive oil factories, and which cannot be used efficiently in certain sectors. Drying experiments were performed at drying temperatures of 60°C, 70°C, and 80°C at a fixed air velocity of 2 m/s using a hot air dryer and with microwave powers of 90 W, 360 W, and 600 W using a microwave dryer. The prina layer thicknesses were selected as 7, 9, and 11 mm for both drying methods. The minimum energy consumption values were measured as 42.0 Wh for 600 W power level and 7 mm layer thickness, and 10260 Wh for 7 mm layer thickness and 80°C temperatures. It was found that energy consumption during hot air drying was more than that of microwave drying. As a result, the suitable dryer and thickness of layer were selected as microwave dryer and 7 mm, respectively. The results of statistical analyses showed that the most suitable model to define the drying behavior of prina samples were found to be the Page model for the microwave dryer and Wang &; Singh model for the hot air dryer. Also, penetration depth, the loss tangent value (tanδ), dielectric constant of material (??), and dielectric loss factor (???) of dried prina were calculated as 34.51 cm, 0.1059, 75.65, and 8.01, at 2450 MHz, respectively.  相似文献   
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