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991.
In this paper, an algorithm is developed to apply Hann, Hamming, Blackman and related windows directly in the transform domain for the discrete cosine transform and discrete sine transform. These algorithms are useful in applications where windowing is required in order to minimize edge effects caused by implicit symmetries in the transform domain that are not replicated in the real-world data. Examples of such applications include data communication, adaptive system identification and filtering, real-time analysis of financial market data, etc. Software implementations in C language are also given. 相似文献
992.
Praveen Sharma P. K. Sharma D.Sc. J. Pramod L. K. Kothari Rashmi Ranka Sushma Sharma 《Indian journal of clinical biochemistry : IJCB》1989,4(1):62-64
Sixteen weeks of chronic vitamin C deficiency, induced in guinea pigs by restricted vitamin C intake, resulted in a marked
increase in the serum total LDL- and VLDL- cholesterol, triglycerides and total lipids. HDL-cholesterol decreased resulting
in a highly significant increase in LDL/HDL ratio. The results reconfirm that vitamin C deficiency causes changes in blood
lipid profile which could promote atherogenesis. 相似文献
993.
994.
Serum free fatty acids (FFA) in 100 parturient (50 primiparous and 50 multiparous volunteers) and 50 female patient (30 patients 20–30 years age group and 20 patients 31–50 yrs age group) volunteers undergoing elective major abdominal surgery were monitored during different stages of delivery and surgery respectively. FFA increased in both primiparous and multiparous from full term (46 mg%) to second stage of labour (60 mg%) and gradually decreased to 38 mg% on the third day postpartum. The intergroup comparison between primiparous and multiparous was significant. Surgical stress also increased FFA from the day of admission (21 mg%) to the preoperative stage (35 mg%). The intergroup comparison between 20–30 yrs age group and 31–50 yrs age group did not show any significant change. 相似文献
995.
996.
997.
In previous work it was established that the U.K. tractor industry was characterised by a high degree of technical change and that this was brought about by a process of more or less continuous incremental innovation. What was lacking was an analysis of how much technical change had been introduced and an indication of the role played by technical change in determining the performance of the U.K. tractor industry internationally. This paper concludes that on the average technical change in the industry had increased by as much as 150 percent during the years 1959–1977, though there is some indication that the rate of change might now be slowing somewhat.In order to determine the relative importance of technical change a method was developed to operationalise the distinction between price and non-price competition as well as the idea of intrinsic (technical) and associative (non-technical) factors as constituents of the latter. Based on cross-sectional data for the year 1978, it has been possible to show that British manufacturers tend to produce moderately priced tractors of low to medium technical sophistication: that German manufacturers produced the most technically sophisticated tractors; that the Italian manufacturers are not generally more sophisticated, technically, than the British producers except with respect to their development of four-wheel drive; and that COMECON-based producers combine a very low price with some degree of technical sophistication. Finally, it has been possible to show that the tractors with the highest sales are among the less sophisticated in each of the power ranges investigated and that new entrants used technical sophistication as an element of their entry strategy. The answer to the question of what allows the market leader to be market leader required the development of measures for associative non-price factors, such as the availability of a dealer network brand loyalty, resale prices of tractor models, etc. By performing a regression analysis on these measures along with previously derived measures of quality-adjusted price and relative technical sophistication it has been possible to show that market leadership is achieved as a result of a balance of a number of factors, the most important of which are the size of the dealer network, warrants cost, advertising, technical sophistication and price. 相似文献
998.
P. D. Anoop 《Resonance》2011,16(1):29-37
This article deals with the timekeepers of the past, the sundials. Apart from discussing the structure of a few common sundials,
we point out the reasons for the variation between sundial time and the time shown by mechanical timekeepers. 相似文献
999.
T. Padmanabhan 《Resonance》2011,16(7):663-669
What was remarkable about the most misunderstood medieval scientist’s discoveries was the way he arrived at them — by direct
observation. 相似文献
1000.
Windsor J Benigno JP Wing CA Carroll PJ Koga SF Nelson CA Fox NA Zeanah CH 《Child development》2011,82(4):1040-1046
This report examines 174 young children's language outcomes in the Bucharest Early Intervention Project, the first randomized trial of foster placement after institutional care. Age of foster placement was highly correlated with language outcomes. Placement by 15 months led to similar expressive and receptive language test scores as typical age peers at 30 and 42 months. Placement from 15 to 24 months also led to dramatic language improvement. In contrast, children placed after 24 months had the same severe language delays as children in institutional care. Language samples at 42 months confirmed that placement after 24 months led to lower expressive skill. 相似文献