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21.
The increasing interest in computer‐aided design (CAD) has prompted research that is aimed at identifying the opportunities for construction managers and building contractors. It has been found that the use of CAD systems in the U.K. is mainly confined to the production of detailed drawings. Indeed, most of the systems used are 2‐D drafting tools and incapable of supporting the integration of even modest amounts of nongraphical (construction) data. On the other hand, many 3‐D modeling systems have the potential to integrate construction data, although they appear to be almost ignored. The use of 3‐D modeling systems is considered to be the most suitable vehicle for successfully integrating these data. However, this is likely to necessitate the introduction of separate databases, preferably of the relational type. The use of 3‐D modeling systems in assessing the construction implications of outline designs also presents interesting possibilities and is discussed. 相似文献
22.
Supplemental niacin for lactating cows during summer feeding 总被引:7,自引:0,他引:7
Five herds with 240 cows were used to determine the response to feeding 6 g/d of supplemental niacin during the summer months. Diets consisted of corn silage, hay crop silage, hay, or pasture as the forage and concentrate. Cows in each herd were paired by lactation number and stage of lactation and randomly assigned to either a control or niacin group and fed niacin once daily for 84 d (July 3 to September 25). Cows averaged 143 d postpartum with a total of 121 and 119 cows on control and niacin groups. Using milk weight and composition prior to initiating the trial as a covariate, least squares means for all cows for control and niacin were milk, 24.5, 25.4 kg/d; milk fat, 3.72, 3.70%; milk fat, .91, .94 kg/d; milk protein, 3.35, 3.34%; and fat-corrected milk, 23.5, 24.3, kg/d. Yields of milk and fat-corrected milk were significantly higher for niacin-supplemented cows. Cows in first lactation and second lactation and greater had a similar response to niacin. Cows producing greater than 34 kg milk produced 2.4 kg more milk with supplemental niacin. Results indicate that feeding 6 g/d supplemental niacin during the summer increased yield of milk and fat-corrected milk but had no effect on milk composition. 相似文献
23.
Atkin G.E. Blake I.F. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1989,35(2):428-435
A novel type of diversity signaling for an M -ary frequency-shift keyed modulation format involving the transmission of multiple tones on each diversity branch is considered. The properties of such a system are investigated, and its performance in the presence of tone jamming is analyzed. It is shown that significant gains can be realized with such a technique. The performance in the presence of worst-case partial band noise is briefly considered and shown to be worse than, though comparable to, that of the single-tone case 相似文献
24.
Sonication‐Assisted Synthesis of Gallium Oxide Suspensions Featuring Trap State Absorption: Test of Photochemistry
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Nitu Syed Ali Zavabeti Md Mohiuddin Baoyue Zhang Yichao Wang Robi S. Datta Paul Atkin Benjamin J. Carey Cheng Tan Joel van Embden Anthony S. R. Chesman Jian Zhen Ou Torben Daeneke Kourosh Kalantar‐zadeh 《Advanced functional materials》2017,27(43)
Gallium is a near room temperature liquid metal with extraordinary properties that partly originate from the self‐limiting oxide layer formed on its surface. Taking advantage of the surface gallium oxide (Ga2O3), this work introduces a novel technique to synthesize gallium oxide nanoflakes at high yield by harvesting the self‐limiting native surface oxide of gallium. The synthesis process follows a facile two‐step method comprising liquid gallium metal sonication in DI water and subsequent annealing. In order to explore the functionalities of the product, the obtained hexagonal α‐Ga2O3 nanoflakes are used as a photocatalytic material to decompose organic model dyes. Excellent photocatalytic activity is observed under solar light irradiation. To elucidate the origin of these enhanced catalytic properties, the electronic band structure of the synthesized α‐Ga2O3 is carefully assessed. Consequently, this excellent photocatalytic performance is associated with an energy bandgap reduction, due to the presence of trap states, which are located at ≈1.65 eV under the conduction band minimum. This work presents a novel route for synthesizing oxide nanostructures that can be extended to other low melting temperature metals and their alloys, with great prospects for scaling up and high yield synthesis. 相似文献
25.
The present study explores the economic and public policy factors that have contributed South Korea’s global leadership in broadband adoption. In particular, the authors explore the economic and public policy factors shaping telecommunication development in South Korea, employing a conceptual framework that explicates a triangular relationship between the government, service providers, and users.
Data used in the study are based on government statistics, company-published information, and secondary sources. Our analysis suggests that (1) the Korean government’s cyber vision plan has provided an open market that encourages competition, as the dramatic growth of the broadband market in Korea is the culmination of appropriate government policy, growing demand, and fierce market competition based on responsive supply, and (2) operators can benefit from consolidation as well as multiple revenue sources generated by new services in order to remain competitive. 相似文献
26.
E. V. Atkin Yu. A. Volkov A. G. Voronin D. V. Dement’ev I. I. Il’yushchenko D. E. Karmanov A. D. Klyuev I. A. Kudryashov A. A. Lobanov D. M. Podorozhnyi V. V. Shumikhin 《Instruments and Experimental Techniques》2012,55(4):456-461
A 32-channel integrated microcircuit for microstrip silicon detectors of the ??Nuklon?? project for studying ionizing radiation in space conditions is tested. The microcircuit allows one to record signals of relativistic particles and nuclei with a charge from Z = 1 up to Z > 50 from silicon detectors. A structural diagram of the microcircuit and its main experimental characteristics are given. The power consumption does not exceed 1.5 mW/channel, and the dynamic range of recorded signals is not smaller than 100 pC. 相似文献
27.
When a subject, seated and facing ahead, was asked to look toward one side, the result was a combined movement of the eyes and head. Normal subjects began the eye movement just before the onset of head movement; 4 neurologic patients who showed abnormalities in eye movements (saccades that tended to be smaller in amplitude and lower in velocity than those of the control subjects) regularly began eye movement after the onset of head movement. Thus the initiation of the head rotation was not as much retarded in these patients as that of eye movement. Amplitudes of the movements were reduced in the patients, but this change too was less for the head than for the eyes. Because the amplitude and velocity of the head movement were less affected in the patient group, the relative contribution of the head to the total gaze shift was increased. It appears as if, when the oculomotor system is affected, the head can assume a leading role in the initiation and execution of gaze shifts. 相似文献
28.
Charles K. Atkin 《The Journal of communication》1978,28(4):71-79
Surveys reveal that exposure shapes children's views of the amount of sickness in society and the efficacy of medicinal cure or relief. 相似文献
29.
Examined the influence of group size, task difficulty, and member sex on the relationship between actual productivity and potential productivity proposed by I. D. Steiner (1972), and tested the predictive accuracy of hierarchical and equalitarian latency models proposed by F. Restle and J. H. Davis (1962). 349 undergraduates worked 3 intellectual problems of varying difficulty, either as individuals or in same-sex groups of 2, 3, 6, and 10 members. Actual performance was assessed using indexes of the proportion of solvers and time to solution. Potential performance scores were generated from theoretical models for the same indexes. Group size and problem difficulty were important determinants of group performance, whereas member sex generally was not. Size and difficulty effects varied depending on choice of performance measure. For the proportion index, groups often worked up to potential, but those same groups usually fell below potential on the latency index; they were effective but inefficient. Group performance on both indexes generally fell below potential as size and difficulty increased. The concept of "functional size" is advanced to explain the observed pattern of group performance: As group size increases the number of nonparticipators also increases, resulting in a functional group size smaller than actual size. (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献