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71.
Extrarenal involvement was found in four cases of renal angiomyolipoma. In one case the wall of the inferior right bronchial artery was infiltrated, lymph nodes were involved in two cases and the perirenal fat in one case. Extrarenal extension does not seem to alter the prognosis of renal angiomyolipoma. Expectant treatment of this rare condition therefore appears to be warranted.  相似文献   
72.
Investigated the effectiveness of implosive therapy with institutionalized emotionally disturbed retardates (mean CA, 21 yrs; mean IQ, 70.3). 24 Ss, matched according to age, sex, race, and IQ, were randomly assigned to 1 treatment and 2 control groups. The treatment group received 10 sessions of implosive therapy. The control groups consisted of a no-treatment control and a group that received 10 sessions of pseudotreatment-oriented discussions. All Ss were maintained on psychiatric medication and participated in the regular hospital activities. The Ss were assessed behaviorally, subjectively, and clinically prior to, at the midpoint, at completion of the experimental conditions, and at a 6-wk follow-up. Following treatment, Ss in the implosive therapy group showed significantly more improvement across all indices than those who received the pseudotherapy-oriented and no-treatment control conditions. Although the implosive therapy group continued to show the most pronounced gains at follow-up, their superiority over the control groups was considerably less than when observed immediately after treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
73.
设计一个室内空间需要你带着感情去做,因为这个空间将会承载你的情感,愤怒、激情和忧郁,我们设计的这个意大利电影导演的PiazzaNavona住宅就是基于这一理念之上。在他的空间里,私人世界和公共生活交汇融合在一起。在设计的过程中,我们花了大量的时间和业主讨论电影、艺术、烹饪  相似文献   
74.
Abstract. Given a set S of radio stations located on a line and an integer h ≥ 1 , the MIN ASSIGNMENT problem consists in finding a range assignment of minimum power consumption provided that any pair of stations can communicate in at most h hops. Previous positive results for this problem are only known when h=|S|-1 or in the uniform chain case (i.e., when the stations are equally spaced). As for the first case, Kirousis et al. [7] provided a polynomial-time algorithm while, for the second case, they derive a polynomial-time approximation algorithm. This paper presents the first polynomial-time, approximation algorithm for the MIN ASSIGNMENT problem. The algorithm guarantees a 2-approximation ratio and runs in O(hn 3 ) time. We also prove that, for fixed h and for ``well spaced' instances (a broad generalization of the uniform chain case), the problem admits a polynomial-time approximation scheme . This result significantly improves over the approximability result given by Kirousis {et al}. Both our approximation results are obtained via new algorithms that exactly solve two natural variants of the MIN ASSIGNMENT problem: the problem in which every station must reach a fixed one in at most h hops and the problem in which the goal is to select a subset of bases such that all the other stations must reach one base in at most h-1 hops. Finally, we show that for h=2 the MIN ASSIGNMENT problem can be exactly solved in O(n 3 ) time.  相似文献   
75.
An optoelectronic target-type volumetric air flow-rate transducer for bidirectional measurements is presented. The sensor is composed of a T-shaped target and two nominally identical LED-photodiode couples which are operated in differential mode. The sensitive surfaces of the photodiodes are differentially shadowed by the deflection of the target, which in turn depends on the gas flow-rate. The principle of operation is described in mathematical terms and the design parameters have been optimized in order to obtain the highest sensitivity along with minimal pressure drop and reduced dimensions. The sensor is placed in a 20 mm diameter hose and was tested with air flow-rate in the typical temperature range of mechanical ventilation between 20 and 40 °C. The theoretical model was validated through experiments carried out in the volumetric flow range from -7.0 to +7.0 l min(-1). The nonlinear behavior allows sensitivities equal to 0.6 V l(-1) min for flow rates ranging from -2.0 to +2.0 l min(-1), equal to 2.0 V l(-1) min for flow rates ranging from -3.0 to -2.0 l min(-1) and from +2.0 to +3.0 l min(-1), up to 5.7 V l(-1) min at higher flow rates ranging from -7.0 to -3.0 l min(-1) and from +3.0 to +7.0 l min(-1). The linear range extends from 3.0 to 7.0 l min(-1) with constant sensitivity equal to 5.7 V l(-1) min. The sensor is able to detect a flow-rate equal to 1.0 l min(-1) with a sensitivity of about 400 mV l(-1) min. The differential nature of the output minimizes the influence of the LEDs' power supply variations and allows to obtain a repeatability in the order of 3% of full scale output. The small pressure drop produced by the sensor placed in-line the fluid stream, of about 2.4 Pa at 7 l min(-1), corresponds to a negligible fluid dynamic resistance lower than 0.34 Pa l(-1) min.  相似文献   
76.
Lignin-derived degradation products from non-treated (NT) and heat-treated (T) Corsican pine (Pinus nigra subsp. laricio) obtained by pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS) were investigated, whereby the earlywood (EW) and latewood (LW) parts of the annual ring were considered separately. The data evaluation was done by principal component analysis (PCA) and the Kruskal–Wallis test. There are no differences in the pyrolysis products composition between EW and LW, but NT and T samples were discernible by PCA applied to Py–GC–MS data. Less phenols with longer chains (4-vinylguaiacol, and trans-isoeugenol) than those with shorter chains (guaiacol, 4-methylguaiacol) and an increase of anhydrosugar (AHS) were found among the pyrolysis products after heat treatment. These signs for autocondensation and side chain cleavages in the lignin during heat treatment were more evident in the EW than in the LW and for the crystallization of cellulose. A slight decrease of the carbohydrate/lignin ratio (C/L) after heat treatment indicates a greater degradation of carbohydrates compared to lignin. The relation of pyrolysis products of lignin and mechanical properties of wood was evaluated by regression analysis. An inverse correlation between short-chain phenols and MOE and a direct correlation between long-chain phenols and compression strength was found in case of NT wood, while a weak positive correlation could be observed between short-chain phenols and the density in T wood.  相似文献   
77.
78.
Computational approaches have been increasingly applied to drug design over the past three decades and have already provided some useful results in the discovery of anticancer drugs. Given the increased availability of crystal structures in recent years, a growing number of molecular modeling studies on tubulin have been reported. Herein we present a brief overview of the role played by computational methods in anti-tubulin research, specifically in the context of colchicine binding agent research. An overview of current structures is reported, along with a brief discussion on the issues associated with the various tubulin isotypes. Finally, a summary of the most recent and relevant results is presented, highlighting the challenges and opportunities faced by researchers in this field.  相似文献   
79.
Permuting a vector is a fundamental primitive which arises in many applications. In particular, rational permutations, which are defined by permutations of the bits of the binary representations of the vector indices, are widely used. Matrix transposition and bit-reversal are notable examples of rational permutations. In this paper we contribute a number of results regarding the execution of these permutations in cache hierarchies, with particular emphasis on the cache-oblivious setting. We first bound from below the work needed to execute a rational permutation with an optimal cache complexity. Then, we develop a cache-oblivious algorithm to perform any rational permutation, which exhibits optimal work and cache complexities under the tall cache assumption. We finally show that for certain families of rational permutations (including matrix transposition and bit reversal) no cache-oblivious algorithm can exhibit optimal cache complexity for all values of the cache parameters. This latter result specializes the one proved by Brodal and Fagerberg for general permutations to the case of rational permutations, and provides further evidence that the tall cache assumption is often necessary to attain cache optimality in the context of cache-oblivious algorithms.  相似文献   
80.
BACKGROUND AND OBJECTIVE: Since 1988 the AIEOP has used BFM-based chemotherapy for childhood ALL. Current organization and results and role of cranial irradiation in the AIEOP-ALL 91 study are reported. DESIGN AND METHODS: From 1991 to 1995, 1194 children (< 15 years) with non-B ALL, were enrolled and assigned to the standard risk [SR: age > 1 year, non-T-ALL, BFM risk factor (RF) < 0.8], intermediate risk (IR: RF > or = 0.8 but < 1.7, or with RF < 0.8 and age < 1 year, or T-ALL), or high risk [HR: RF > or = 1.7, or t(9;22), or t(4;11) or prednisone poor response or late response or CNS involvement] groups. All patients received initially protocol Ia. Thereafter SR patients received HD-MTX 2 g/m2, a modified protocol II, and continuation therapy with triple intrathecal chemotherapy (TIT); IR patients received protocol Ib, HD-MTX 5 g/m2, protocol II and continuation therapy with TIT; HR patients received 9 polychemotherapy blocks, cranial irradiation and continuation therapy. Duration of treatment was 24 months. A randomized study was conducted to evaluate the impact of high-dose asparaginase in non high risk patients: the results of this study cannot be disclosed yet. RESULTS: One thousand one hundred and fifty-two (96.5%) patients achieved CR. Overall EFS (SE) at 5-years was 71.0% (1.4), with a survival of 80.3% (1.3). Relapse occurred in 262 children (21.9%), either in the marrow (n = 192 isolated and 32 with other sites, 18.7%), in the CNS (n = 18, 1.5%), or elsewhere (n = 20, 1.7%). 5-year EFS (SE) was 83.3% (2.4) in SR, 74.7% (1.8) in IR, and 39.7% (3.5) in HR groups, respectively. INTERPRETATION AND CONCLUSIONS: Overall cure rate was higher than in the previous AIEOP-ALL 88 study. Treatment intensification with polychemotherapy blocks did not improve results in HR. Cranial irradiation can be safely omitted in over 80% of children treated with BFM based chemotherapy.  相似文献   
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