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991.
The main principles of a measurement procedure are given and its implementation with the aid of an IR-imager AGA-780 is shown.State Institute of Applied Optics, Kazan. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 63, No. 1, pp. 109–113. July, 1992. 相似文献
992.
993.
P. Kristiansson C. M. Nilsson H. Busk L. Malmqvist M. Elfman K. G. Malmqvist J. Pallon K. A. Sj land R. J. Utui C. Yang 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1997,130(1-4):303-307
A technique for measuring optical dot gain, i.e. the relative difference between the actual screen dot and the optically perceived one, is presented. By combining measurements from the non-optical nuclear microprobe with data from image analyzing technique the optical dot gain can be determined. The procedure to reach pixel by pixel correlation on a micrometer scale is discussed. In the newsprint sample studied in this investigation a typical optical dot gain between 15 and 20% was deduced. The variation in the optical dot gain was correlated with other characteristic parameters of the print and newsprint and especially a positive correlation to the mass density of the newsprint was observed. 相似文献
994.
J Norris L Harnack S Carmichael T Pouane P Wakimoto G Block 《Canadian Metallurgical Quarterly》1997,87(5):740-746
OBJECTIVES: This study examined US trends in nutrient intake, using almost identical methods and nutrient databases in two time periods. METHODS: An extensive dietary intake questionnaire was included in supplements to the 1987 and 1992 National Health Interview Surveys. Dietary data from approximately 11,000 persons in each of those years were analyzed. RESULTS: The total and saturated fat intake and the percentage of energy from fat declined among Whites and Hispanics, but only minimal changes were seen in Black Americans. The changes in fat intake were attributable principally to behavioral changes in frequency and type of fat-containing foods consumed rather than to the increased availability of leaner cuts of meat. Dietary cholesterol showed one of the largest declines of the nutrients examined. Less desirable changes were also seen. Cereal fortification played an important role in the observed changes in several micronutrients. CONCLUSIONS: Educational campaigns on dietary fat and cholesterol have been moderately effective, but not in all racial/ethnic groups. Future campaigns should emphasize maintaining or increasing micronutrient intake. 相似文献
995.
Inflammatory pseudotumour is not a common lesion. The first series of 12 cases was described in 1986, to which 37 more cases have now been added. The histology, differential diagnosis, and prognosis of this lesion have been described in detail, but the aetiology is unknown and the mode of treatment remains controversial. A new case is presented and compared with the previously reported cases. Fine needle aspirate yielded a growth of klebsiella organisms. The possibility of this infection as an aetiological agent is considered. 相似文献
996.
A new enzyme immunoassay for the detection of specific antibodies to rubella virus was evaluated at two different sites. This assay, the Roche Cobas Core Rubella IgM EIA recomb, uses a recombinant rubella virus-like particle and is based upon the immunoglobulin M (IgM) capture principle. It was compared to the Abbott IMx Rubella IgM test and to the Sorin ETI-RUBEK-M reverse test. The relative clinical specificities were 99.30% for the Roche test, 98.26% for the Abbott test, and 100% for the Sorin test. The relative clinical sensitivities were 100, 93.87, and 82.65%, respectively. In the case of most primary infections, IgM antibodies could be detected immediately at the onset of the disease and for up to 7 weeks. In the case of vaccinations, they could be detected between 3 and 12 weeks after vaccination. 相似文献
997.
A Lander R Redkar G Nicholls A Lawson SR Choudhury JJ Corkery P Gornall RG Buick IW Booth 《Canadian Metallurgical Quarterly》1997,77(2):F119-F122
AIM: To assess the efficacy of cisapride in reducing ileus persisting to the tenth postoperative day after neonatal abdominal surgery. METHODS: A prospective, randomised, double blind trial comparing rectal cisapride (1.4-2.3 mg/kg/day) with placebo over seven days was undertaken in 33 neonates. RESULTS: Seven of 12 (58%) patients receiving placebo and eight of 11 (73%) receiving cisapride achieved a first sustained feed during treatment. Of those receiving cisapride, the first sustained feed occurred at 2.3 days (SEM 0.6) compared with 4.7 days (SEM 0.8) with placebo. By the seventh day the mean daily net enteral balance was 69 (SEM 18) ml/kg in the cisapride subgroup and 17 (SEM 8) ml/kg for those receiving placebo. Stool was passed on 6.3 (SEM 0.4) treatment days in the cisapride subgroup compared with 4.1 (SEM 1.0) treatment days in the placebo subgroup. CONCLUSION: Cisapride is effective in neonates with a prolonged ileus after abdominal surgery. 相似文献
998.
The lack of physical fitness is a contributing factor to the etiology of musculoskeletal disorders resulting from the manual handling of material in industry. Thus the major objectives of this paper were (1) to discuss the role of physical fitness in the control of occupational injuries; (2) to review techniques available in the exercise physiology literature for increasing human physical capacity in industry; and (3) to review and evaluate studies on the effects of physical training on individuals engaged in manual handling tasks. 相似文献
999.
The performance of a multiple-cell direct-sequence code division multiple-access cellular radio system is evaluated. Approximate expressions are obtained for the area-averaged bit error probability and the area-averaged outage probability for both the uplink and downlink channels. The analysis accounts for the effects of path loss, multipath fading, multiple-access interference, and background noise. Two types of differentially coherent receivers are considered: a multipath rejection receiver and a RAKE receiver with predetection selective combining. Macroscopic base station diversity techniques and uplink and downlink power control are also topics of discussion 相似文献
1000.
A new SPICE subcircuit model for power p-i-n diodes is proposed in this paper. The model is based on a moment-matching approximation of the ambipolar diffusion equation. It is shown that both the quasistatic model and the lumped charge model can be obtained as ion-order moment-matching approximations while new and more accurate models can be obtained from higher-order solutions. The proposed model takes into account emitter recombination in the highly doped end regions, conductivity modulation in the base and the moving-boundaries effect during reverse-recovery, showing good convergence properties and fast simulation times. Comparisons between the results of the SPICE model and both numerical device simulations and experimental results are presented 相似文献