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We investigate phase-sensitive interference effects in a periodically sin(2π f rf t)-driven, artificial two-state system connected to a microwave resonator at f LC ? 800 MHz. We observe two kinds of multiphoton transitions in the two-state system, accompanied by: (1) Several quanta from the drive at f rf and (2) one quantum at f rf and several at f LC . The former are described using phase-sensitive Landau–Zener transitions, while the latter are discussed in terms of vibronic transitions in diatomic molecules. Interference effects in the vibronic transitions governed by Franck–Condon coefficients are also considered.  相似文献   
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Fermented soymilk with a monoculture of Lactococcus lactis   总被引:1,自引:0,他引:1  
Lactococcus lactis strain (LL3) isolated from mothers' milk was used to produce fermented soymilk. The strain survived at levels of over 7 log cfu/ml for 3 weeks in the fermented soymilk. A consumer survey was carried out to compare the acceptability of the fermented product with a similar product made with L. lactis ATCC11545 originally isolated from cow's milk. Blind samples produced by fermentation with the two strains were rated equally attractive, whereas information on the origin of the strains significantly enhanced the pleasantness of the fermented soymilk.  相似文献   
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Expected and actual acceptance of three unfamiliar vs. three familiar foods were examined among US subjects to determine the extent to which positive information about their origin, nutritional properties and flavor, in the presence or absence of product category information, contributed to their acceptance. Subjects (n=160) were divided into the following four conditions: (1) ‘NOI' Unfamiliar foods, no verbal information; (2) ‘INFO' Unfamiliar foods, positive information without product category; (3) ‘INFO+' Unfamiliar foods, positive information including product category; and (4) ‘CTR' Familiar foods, no information, control group. The subjects rated their expected liking/disliking prior to tasting (based on information in conditions 2 and 3, and based on appearance in all conditions), their actual liking, and the degree to which the foods matched/mismatched their sensory and hedonic expectations after tasting. Generally, positive information enhanced ratings of unfamiliar samples, but product-specific information effects were large, and no proof was obtained for the superiority of the INFO+ (compared to INFO) condition in the enhancement of liking. Actual liking was best predicted by expected liking based on either verbal information or on seeing the product. The expected liking was mainly predicted by the degree of liking and frequency of use of the specific familiar reference products. Thus, the acceptance of an unfamiliar food is largely determined by how it relates to familiar foods that are part of an individual's current diet.  相似文献   
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The desire to increase profit on dairy farms necessitates consideration of the revenue attainable from the sale of surplus calves for meat production. However, the generation of calves that are expected to excel in efficiency of growth and carcass merit must not be achieved to the detriment of the dairy female and her ability to calve and re-establish pregnancy early postcalving without any compromise in milk production. Given the relatively high heritability of many traits associated with calving performance and carcass merit, and the tendency for many of these traits to be moderately to strongly antagonistic, a breeding index that encompasses both calving performance and meat production could be a useful tool to fill the void in supporting decisions on bull selection. The objective of the present study was to derive a dairy–beef index (DBI) framework to rank beef bulls for use on dairy females with the aim of striking a balance between the efficiency of valuable meat growth in the calf and the subsequent performance of the dam. Traits considered for inclusion in this DBI were (1) direct calving difficulty; (2) direct gestation length; (3) calf mortality; (4) feed intake; (5) carcass merit reflected by carcass weight, conformation, and fat and the ability to achieve minimum standards for each; (6) docility; and (7) whether the calf was polled. Each trait was weighted by its respective economic weight, most of which were derived from the analyses of available phenotypic data, supplemented with some assumptions on costs and prices. The genetic merit for a range of performance metrics of 3,835 artificial insemination beef bulls from 14 breeds ranked on this proposed DBI was compared with an index comprising only direct calving difficulty and gestation length (the 2 generally most important characteristics of dairy farmers when selecting beef bulls). Within the Angus breed (i.e., the beef breed most commonly used on dairy females), the correlation between the DBI and the index of genetic merit for direct calving difficulty plus gestation length was 0.74; the mean of the within-breed correlations across all other breeds was 0.87. The ranking of breeds changed considerably when ranked based on the top 20 artificial insemination bulls excelling in the DBI versus excelling in the index of calving difficulty and gestation length. Dairy breeds ranked highest on the index of calving difficulty and gestation length, whereas the Holstein and Friesian breeds were intermediate on the DBI; the Jersey breed was one of the poorest breeds on DBI, superior only to the Charolais breed. The results clearly demonstrate that superior carcass and growth performance can be achieved with the appropriate selection of beef bulls for use on dairy females with only a very modest increase in collateral effect on cow performance (i.e., 2–3% greater dystocia expected and a 6-d-longer gestation length).  相似文献   
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We study numerically the onset of higher-level excitations and resonance frequency shifts in the generalized multilevel Rabi model with dispersive coupling under strong driving. The response to a weak probe is calculated using the Floquet method, which allows us to calculate the probe spectrum and extract the resonance frequency. We test our predictions using a superconducting circuit consisting of a transmon coupled capacitively to a coplanar waveguide resonator. This system is monitored by a weak probe field and at the same time driven at various powers by a stronger microwave tone. We show that the transition from the quantum to the classical regime is accompanied by a rapid increase of the transmon occupation and consequently that the qubit approximation is valid only in the extreme quantum limit.  相似文献   
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Today, outsourced manufacturing of integrated circuit designs are prone to a range of malicious modifications of the circuitry called Hardware Trojans. HTs can alter the functionality of a circuit, leak secret information and initiate other possible malicious actions. HTs are activated in a very rare condition known by an intruder. Therefore, a group of HT detection methods tries to activate the HT circuitry by crafting test vectors. In this paper, we propose a logic testing based HT detection method using an advised genetic algorithm which creates effective test vectors, the so-called TRIAGE (hardware TR ojan detectI on using an A dvised G enetic algorithm based logic tE sting). The key contribution of this paper is to present a proper fitness function for the genetic algorithm providing better evaluation of the test vectors. The controllability, observability and transition probability factors of rare nodes have been considered in the fitness function. Simulation results indicate 80% reduction in generation time for test sets (on average) as compared to the previous work. On the other hand, reduced generation time for test vectors has been associated with an increase in trigger coverage. The coverage of the TRIAGE method for very hard to trigger Trojans increases by about 23% due to high efficiency of the proposed fitness function for the genetic algorithm.  相似文献   
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Environmental factors can accelerate telomere length (TL) attrition. Shortened TL is linked to attention deficit/hyperactivity disorder (ADHD) symptoms in school-aged children. The onset of ADHD occurs as early as preschool-age, but the TL-ADHD association in younger children is unknown. We investigated associations between infant TL and ADHD symptoms in children and assessed environmental factors as potential confounders and/or mediators of this association. Relative TL was measured by quantitative polymerase chain reaction in cord and 12-month blood in the birth cohort study, the Barwon Infant Study. Early life environmental factors collected antenatally to two years were used to measure confounding. ADHD symptoms at age two years were evaluated by the Child Behavior Checklist Attention Problems (AP) and the Attention Deficit/Hyperactivity Problems (ADHP). Associations between early life environmental factors on TL or ADHD symptoms were assessed using multivariable regression models adjusted for relevant factors. Telomere length at 12 months (TL12), but not at birth, was inversely associated with AP (β = −0.56; 95% CI (−1.13, 0.006); p = 0.05) and ADHP (β = −0.66; 95% CI (−1.11, −0.21); p = 0.004). Infant secondhand smoke exposure at one month was independently associated with shorter TL12 and also higher ADHD symptoms. Further work is needed to elucidate the mechanisms that influence TL attrition and early neurodevelopment.  相似文献   
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