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1.
In the optimization of the number of good chips per wafer, yield is obviously one key factor. It plays the major role in the manufacturing phase, as at this time circuit design and chip area cannot be modified. In the design phase, however, chip area as the second factor defining good chips per wafer can still be influenced. If there are no strong relationships between yield and chip area, both can be optimized independently. In some cases, however, there are such strong relationships, and an optimum of yield gain versus area growth has to be found. Maybe the most important example where strong relationships between area and yield have to be considered is the estimation of optimum memory redundancy. In this paper, we will review and discuss relationships between yield and area and present methods for optimization of good chips per wafer, with special focus on the optimization of memory redundancy  相似文献   
2.
A trench-Hall device sensitive to magnetic inductions parallel to the chip surface is reported in this paper. The vertically oriented active region is defined by two parallel trenches with a distance of only 2.4 μm. Deep contacts connect the active region of the device at its bottom at a depth of 20 μm. These deep contacts allow a symmetrical operating condition of the active region analogous to a lateral symmetrical Hall plate, which is favorable for dynamic offset reduction. With the presented technology, trench-Hall devices with a sensitivity of 320 V/A with a nonlinearity below 0.1% are realized. Additionally, the presented fabrication technique enables the electrically insulated cointegration of sensor and circuitry on a single CMOS chip  相似文献   
3.
A survey was conducted in a sample of 894 students entering a private university in S?o Paulo to examine the vitamin beliefs and to verify the relation between vitamin beliefs and vitamin supplements consumption. Nineteen statements about the relation between vitamins and health were developed to assess the beliefs; the respondents answered by means of a 5-point agreement scale. Cronbach's alpha coefficient of internal consistency was determined for the total scale. 94.5% of students believe that vitamin C prevents and cures the common cold and 72.5% consider vitamins as an energy source. Many students recognize the possibility of health risks associated to excessive vitamin consumption. Vitamin supplement users had a belief score higher than non-users (p < 0.001). The results indicate that several misconceptions about vitamin benefits are common among the students and suggest a relation between vitamin beliefs and supplements consumption.  相似文献   
4.
Very thin SiO2 films (3–6 nm) have been characterized with a conductive atomic force microscope (C-AFM). The set-up allows the electrical characterization of 30–50 nm2 areas, which are of the order of single breakdown spots. Voltage ramps have been repeatedly applied to induce the degradation. On these spots, the phenomenology observed is quite similar to that during conventional electrical tests. In particular, on–off fluctuations before and after breakdown are reported on single breakdown spots. The results confirm the C-AFM as a suitable tool for the analysis of the gate oxide electrical properties and degradation dynamics at a nanometer scale.  相似文献   
5.
In this study, the authors aimed to identify patterns of autonomic dysfunction and neurocognitive deficit recovery. The authors performed laboratory assessments on 66 patients with schizophrenia immediately after an acute psychotic episode and 6, 12, and 18 months later. Shortly after the psychotic episode, the patients displayed cardiovascular hyperarousal at rest, cardiovascular and electrodermal hyporeactivity during 2 Continuous Performance Tasks (CPTs) and deficits in 2 behavioral CPT measures (i.e., reaction time and omission error rate) compared with 29 normal controls. In the subsequent postpsychotic course, changes indicative of a process of recovery occurred in all measurement areas, although with regard to autonomic hyporeactivity amelioration was limited to a subgroup of schizophrenics with complete and persistent symptomatic remission. Neurocognitive improvement in CPTs did not appear to depend on unimpaired autonomic reactivity mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
PURPOSE: To determine the effects of saline, heparin 2 units (U) per ml saline, and heparin 10 U/ml saline flush solutions on the duration of intravenous (i.v.) locks and the incidence of i.v. infiltration in neonates. DESIGN: Randomized double-blind experiment. SETTING: Tertiary-care nursery. PARTICIPANTS: Neonates (N = 90) hospitalized at birth in the intensive, intermediate care, or newborn units. MAIN OUTCOME MEASURES: Total hours from the time the i.v. was inserted to the time the i.v. was removed; hours from the time the i.v. was first flushed to the time the i.v. was removed; number of i.vs. removed because of infiltration. RESULTS: No statistical or clinical differences between the three groups for duration of i.v. nor for incidence of complications. CONCLUSIONS: The use of heparin in i.v. lock flush solution did not affect the duration of i.v. locks nor the incidence of infiltration in neonates.  相似文献   
7.
PURPOSE: We report a patient with mesial temporal lobe epilepsy (MTLE) with olfactory prodromal symptoms manifested as an unpleasant smell of onions, who was found to have an ipsilateral deficit of olfactory naming (olfactory agnosia). METHODS AND RESULTS: Preoperative olfactory testing revealed a selective right-sided olfactory deficit for naming of odors. Olfactory threshold was within the normal range. The patient has been seizure free after selective amygdalohippocampectomy for 4 months. No olfactory prodromal events have occurred since surgery. Olfactory testing 3 months after resection showed that right-sided odor naming was still impaired. CONCLUSIONS: We conclude that olfactory prodromal symptoms may be associated with unilateral olfactory dysfunction, and lateralization of seizure origin may be possible by unilateral olfactory testing.  相似文献   
8.
Investigated cognitive concomitants of performance changes in an achievement-related context, using 32 undergraduates. Ss' verbalizations of action-oriented and state-oriented cognitions were monitored while they experienced success and failure. An analysis was made of the influence of dispositional action control and perceptions of emotional states and personal control. Results reveal that dispositional action control was an excellent predictor of performance changes that followed failure inductions: Only a state-oriented group displayed performance decrements, whereas an action-oriented group continued to perform well, using effective problem-solving strategies and self-motivating instructions. Whereas action-oriented Ss responded to persistent failure with continuing solution-oriented thinking and developed even more efficient strategies, state-oriented Ss increased emotional and self-evaluative statements, related failure to loss of ability, and used inadequate solution strategies. The 2 groups differed with regard to perceptions of personal control and competence. Results suggest that the debilitating or facilitating influence of failure inductions on performance is mediated by 2 different processing styles of action vs state orientation. (46 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
A particular property of the sleeping brain is that it exhibits dynamics on very different time scales ranging from the typical sleep oscillations such as sleep spindles and slow waves that can be observed in electroencephalogram (EEG) segments of several seconds duration over the transitions between the different sleep stages on a time scale of minutes to the dynamical processes involved in sleep regulation with typical time constants in the range of hours. There is an increasing body of work on mathematical and computational models addressing these different dynamics, however, usually considering only processes on a single time scale. In this paper, we review and present a new analysis of the dynamics of human sleep EEG at the different time scales and relate the findings to recent modelling efforts pointing out both the achievements and remaining challenges.  相似文献   
10.
'Complexity science' is a rapidly developing research direction with applications in a multitude of fields that study complex systems consisting of a number of nonlinear elements with interesting dynamics and mutual interactions. This Theme Issue 'The complexity of sleep' aims at fostering the application of complexity science to sleep research, because the brain in its different sleep stages adopts different global states that express distinct activity patterns in large and complex networks of neural circuits. This introduction discusses the contributions collected in the present Theme Issue. We highlight the potential and challenges of a complex systems approach to develop an understanding of the brain in general and the sleeping brain in particular. Basically, we focus on two topics: the complex networks approach to understand the changes in the functional connectivity of the brain during sleep, and the complex dynamics of sleep, including sleep regulation. We hope that this Theme Issue will stimulate and intensify the interdisciplinary communication to advance our understanding of the complex dynamics of the brain that underlies sleep and consciousness.  相似文献   
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