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91.
The deterioration of operating margin and increasing leakage current in SRAM are becoming critical problems with the advance of process scaling. To solve these problems, we propose a low-power SRAM circuit using thin buried-oxide fully depleted silicon-on-insulator transistors. The back-gate bias is introduced to the SRAM circuits and acquires high operating margin and high-speed operation under low supply voltage. The leakage current in stand-by state is reduced. This SRAM achieves 30% faster writing time under low-voltage operation and 90% less stand-by power  相似文献   
92.

We consider in this paper a model of asymmetric power-transformation of response probability explained by linear function of some covariates. This model includes logistic and complementary log-log transformation models as its specific case, so we can use the model to evaluate the appropriateness or the goodness of fit of these models. Then the performances of the asymmetric power-transformation model are evaluated and examined, based on data used in published literatures. And we discuss various issues of diagnoses which may occur in the process of applying the model. Further we consider alternative transformations, and then in comparison with them, we point out the advantages of the asymmetric power-transformation.

  相似文献   
93.
A 1 Mb 5 V-only EEPROM (electrically erasable programmable ROM) with metal-oxide-nitride-oxide-semiconductor (MONOS) memory cells specifically designed for a semiconductor disk application is described. The memory has high endurance to write/erase cycles and a relatively low programming voltage of ±9 V. These advantages result from the structure and the characteristics of the MONOS memory cell. A newly developed dual-gate-type MONOS memory cell has a small unit cell area of 18.4 μm2 with 1.2 μm lithography, and the die size of the fabricated chip is 5.3 mm×6.3 mm. A new programming scheme called multiblock erase solved the problem of slow programming speed. A programming speed of up to 1.1 μs/B equivalent (140 ms/chip) was obtained  相似文献   
94.
This paper presents an analytical model for evaluating the availability of distributed processing systems. The model, which is based on a well-known probability formula, has been implemented in FORTRAN and used for the design of a real-time distributed processing system that requires high availability. It is applied to a sample distributed processing system to illustrate its usefulness and to provide good insight into the design of highly available distributed processing systems. Effects of homogeneous/heterogeneous clustering and standby spare are illustrated. The concept of availability threshold where the distributed system may gain or lose availability over the individual processor availability is introduced. It has proven to be a valuable tool for the tradeoffs in the allocation of system requirements. The concluding remarks summarize the lessons learned and suggest cost-effective ways to achieve higher availability for the design of distributed processing systems.  相似文献   
95.
A prospective randomized joint study was conducted to evaluate the usefulness of UFT 1) as a postoperative adjuvant therapy in patients with invasive bladder cancer who had undergone curative combination therapy with operation and/or chemotherapy and/or radiation therapy, 2) as an endocrine chemotherapy in patients with newly diagnosed stage C/D prostate cancer, for a period of 3 years from January, 1992. For bladder cancer, of 36 patients with invasive bladder cancer, clinically cured by combination therapy, 20 patients were treated with UFT as an adjuvant chemotherapy over 12 months, and they were compared to 16 patients with no adjuvant therapy. After excluding 10 inappropriate patients, 12 patients in the UFT treatment group and 14 patients with no adjuvant treatment group were observed. For prostate cancer, of 29 patients with clinically stage C/D prostate cancer, 13 were treated with endocrine therapy in combination with UFT, and 16 patients were treated with endocrine therapy alone. After excluding 7 inappropriate patients, 10 patients with endocrine chemotherapy and 12 patients with hormonal therapy were observed. The non-recurrence rate, survival rate and side effects of UFT were evaluated. In the study of bladder cancer, neither a significant difference of non-recurrent rate nor of survival rate was seen between the two groups. In the study of prostate cancer, neither a significant difference of non-recurrent rate nor of survival rate was seen between the two groups. These findings suggest UFT is less useful as an adjuvant therapy for the invasive bladder cancer and as an endocrine chemotherapy for newly diagnosed advanced prostate cancer.  相似文献   
96.
97.
The toxic gases released by combustion/pyrolysis of wool include CO, HCN and four compounds containing sulphur. Animal test data suggest that the toxicity of the sulphur compounds is significant. Wool was pyrolysed and the gases were analysed by GC-MS. SO2 was the main sulphur-containing gas produced by flaming combustion in an oxygen-enriched atmosphere. In pyrolysis under various conditions COS was a major sulphur-containing product. Although it is a highly toxic gas, COS has not so far been reported by workers engaged in the toxicity of fire gases. It is suggested that analysis of COS be included in the analytical toxicology of sulphur-containing polymers.  相似文献   
98.
This paper shows that optimal preview control system approaches to a decoupled preview control system as the weighting factors for the control input variables in the quadratic performance index tend towards zero. Therefore, to examine the characteristics of the decoupled preview control system also means to examine the asymptotic characteristics of the optimal preview control system. By this property, relationships between the design parameters and the response of the optimal preview control system become clear and the design of the optimal preview control can be simplified by utilizing the properties that the decoupled preview control system features. Further, the decoupled preview control method is applied to the vector control system for an induction motor drive. By this application, a trade off between the conditions of the vector control and the magnitude of input variables becomes easy. To demonstrate the significance of this proposed method, simulation results of this application are carried out  相似文献   
99.
A method for evaluating wall condition by using plasma impact desorption (PID) technique has been developed and successfully applied to the tandem mirror GAMMA 10 as a monitor for wall conditioning. A magnetically shielded quadrupole mass spectrometer was installed in the vacuum chamber of the GAMMA 10 central cell. The behaviour of the partial pressure of various gas molecules desorbed by ICRF-heated plasma discharges were analyzed. The predominant increase of the partial pressure due to PID (ΔPPID) was hydrogen (M = 2) and a small amount of impurity as CO (M = 28), CH3 (M = 15), H2O (M = 18) and CO2 (M = 44) was observed in the wall-conditioning discharges. The reduction of hydrogen pressure as well as ΔPPID of the above impurities was observed with the progress of wall conditioning. This behavior has a good correlation with the increase of partial pressures due to electron-impact desorption measured at the same period. The relation between ΔPPID and the charge-exchange flux was investigated.  相似文献   
100.
One hundred and eighty eight children with acute lymphoblastic leukemia (ALL) were treated in a Children's Cancer and Leukemia Study Group high-risk ALL 874 study from April, 1987 to September, 1991. These patients received a four-drug induction regimen followed by the early consolidation regimen, cranial irradiation at 6 months of remission and three years of continuation therapy with rotational administration of four drugs. The patients were randomized into two regimens. In regimen A, the consolidation chemotherapy consisted of the intermediate dose cytosine arabinoside (Ara-C), cyclophosphamide (CPM) plus 6MP, and in regimen B, it consisted of high-dose Ara-C plus CPM. Regimen A was given to 106 patients and 82 patients received regimen B. The complete remission induction rate for regimen A and B was 89.4% (93/104) and 98.7% (78/79), respectively. The 3-year event-free-survival (EFS) rate was 70.6% for regimen A, which was higher than the 56.7% for regimen B. The 3-year EFS rate was 44.4% for the 53 patients with an initial leukocyte count > or = 10 x 10(4)/microliters and 72.2% for 132 patients with a leukocyte count < 10 x 10(4)/microliter. We considered that Ara-C plus L-asp, added to the conventional high-risk ALL 811 protocol, improved the prognosis of the high risk ALL patients. However, further intensive chemotherapy was required for improvement of the outcome of the patients with hyperleukocytosis (> or = 10 x 10(4)/microliters).  相似文献   
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