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1.
To identify possible sources of the observed differences in the career choices of women and men, three facets of career preferences were examined: the relative importance attributed to career-related aspects, the within-aspect preferences (i.e., desirable characteristics of occupations), and the structure of aspects derived from these within-aspect preferences. The career-related preferences of 2,000 young adults who were in the process of making their career decisions were analyzed. These career-related preferences were elicited during their dialogues with a computer-assisted career guidance system. The analyses revealed (a) only small gender differences in the relative importance of the aspects, (b) considerable gender differences in the within-aspect preferences, and (c) certain gender differences in the structure of aspects. The findings and their possible theoretical and practical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
In this note, we introduce the framework of partial difference equations (PdEs) over graphs for analyzing the behavior of multi-agent systems equipped with decentralized control schemes. Both leaderless and leader-follower models are considered. PdEs mimic partial differential equations (PDEs) on graphs and can be studied by introducing concepts of functional analysis strongly inspired to the corresponding ones arising in PDEs theory. We generalize different models proposed in the literature by introducing errors in the agent dynamics and analyze agent coordination through the joint use of PdEs and automatic control tools. Moreover, for the simplest control schemes, we show that the resulting PdEs enjoy properties that are similar to those of well-known PDEs like the heat equation, thus allowing to exploit physical-based reasoning for conjecturing formation properties.  相似文献   
3.
High-field, high-speed magnetic resonance imaging (MRI) can generate high levels of noise. There is ongoing concern in the medical and imaging research communities regarding the detrimental effects of high acoustic levels on auditory function, patient anxiety, verbal communication between patients and health care workers and ultimately MR image quality. In order to effectively suppress the noise levels inside MRI scanners, the sound field needs to be accurately measured and characterized. This paper presents the results of measurements of the sound radiation from a gradient coil cylinder within a 4 T MRI scanner under a variety of conditions. These measurement results show: (1) that noise levels can be significantly reduced through the use of an appropriately designed passive acoustic liner; and (2) the true noise levels that are experienced by patients during echo planar imaging.  相似文献   
4.
In this letter, the uncertainties on the angles of propagation of a plane wave in a bio electromagnetic application are studied using two non intrusive stochastic collocation methods. The proposed techniques are used in this application, which employs a finite-difference time-domain scheme, but they can be used when applying other kinds of methods without modifying programs. The results obtained using the two approaches are compared. The stochastic collocation methods are used to determine the influence of the uncertainty on the angle of propagation of a plane wave on the obtained specific absorption rate. Global sensitivity is analyzed.  相似文献   
5.
We investigated possible explanations of the finding that the relative weight (W) of common components in similarity judgments is higher for verbal than for pictorial stimuli. A serial presentation of stimulus components had no effect on verbal stimuli; it increased the impact of both common and distinctive components of pictorial stimuli but did not affect their relative weight. On the other hand, W was increased by manipulations that reduced the cohesiveness of composite pictures, such as separating, scrambling, and mixing their components. Furthermore, W was decreased by manipulations that enhanced the cohesiveness of composite verbal stimuli by imposing structure on their components. Verbal and pictorial representations of the same stimuli yielded no systematic differences in W. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
The assessment of the exposure to electromagnetic waves is nowadays a key question. Dealing with the relationship between exposure and incident field, most of previous investigations have been performed with a single plane wave. Realistic exposure in the far field can be modeled as multiple plane waves with random direction of arrival, random amplitude, and random phase. This paper, based on numerical investigations, studies the whole body specific absorption rate (SAR) linked to the exposure induced by five random plane waves having uniformly distributed angles of arrival in the horizontal plane, log-normal distributed amplitudes, and uniformly distributed phases. A first result shows that this random heterogeneous exposure generates maximal variations of ??25% for the whole body specific absorption. An important observation is that the exposure to a single plane wave arriving face to the body, used for the guidelines, does not constitute the worst case. We propose a surrogate model to assess the distribution of the whole body SAR in the case of an exposure to multiple plane waves. For a sample of 30 values of whole body SAR induced by five plane waves at 2.4?GHz, this simple approach, considering the resulting SAR as the sum of the SAR induced by each isolated plane wave, leads to an estimated distribution of whole body SAR following the real distribution with a p value of 76% according to the Kolmogorov statistical test.  相似文献   
7.
Ninety patients with carcinoma of the hypopharynx underwent pharyngolaryngectomy and reconstruction with a jejunal free autograft. Fifty-five patients had primary surgery and 35 salvage surgery for recurrence after radiotherapy. Following primary surgery 28 patients had postoperative radiotherapy and 27 did not. Complications occurred in 51 per cent of patients, the most common being necrosis of the jejunal graft (19 per cent); 12 per cent developed significant stenosis and 4 per cent died in the perioperative period. Eleven per cent of patients developed a fistula. The total number of complications diminished as the experience of the unit increased. Median follow-up was 4.9 years. Of patients treated with primary surgery, 48 per cent developed primary site recurrence (at 3 years) and 53 per cent neck node recurrence (at 5 years). The tumour-specific 5-year survival rate for all patients was 42 per cent. Following primary surgery 28 per cent survived for 5 years and after salvage surgery the rate was 59 per cent. Positive resection margins and extensive neck disease adversely affected survival (P = 0.02 and P = 0.001 respectively). The free revascularized jejunal graft is a safe and predictable method of repair following total pharyngolaryngectomy.  相似文献   
8.
9.
Investigated the processes that underlie career-related preferences and the readiness to make compromises. In Study 1, 3,265 monitored dialogs with a computer-assisted career guidance system were analyzed. In Study 2, the occupational preferences of 60 young adults elicited by detailed questionnaires were analyzed. Within-S analyses in both studies supported the following hypotheses: (1) The perceived importance of an aspect is positively correlated with the degree of extremity of preference; (2) the perceived importance of an aspect is negatively correlated with the readiness to compromise in it; (3) the perceived importance of an aspect is positively correlated with the variance in the individual's preferences; and (4) the readiness to compromise depends on the preferences within an aspect. These findings are discussed in light of the roles of preferences and compromises in career decisions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Functional magnetic resonance imaging has become an invaluable tool for cognitive neuroscience, despite the fact that many of the physiological mechanisms giving rise to the effect are not well understood. We review the known biochemical and physiological basis of the technique and discuss how, within the noted limits, one might fully exploit the spatial and temporal resolution that is intrinsic to the very high magnetic fields that we use for human studies. This noninvasive brain mapping technique relies on the changes in blood oxygenation, blood volume, and blood flow, and we discuss some of the issues influencing the effects of these hemodynamic parameters on image intensity.  相似文献   
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