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61.
Laura M. Neuendorf Dr. rer. nat. Valentin Khaydarov Christiane Schlander Tobias Kock Joshua Fischer Prof. Dr.-Ing. Leon Urbas Prof. Dr.-Ing. Norbert Kockmann 《化学,工程师,技术》2023,95(10):1546-1554
Image analysis presents a set of powerful methods to receive additional information about multiphase processes. It enables the development of advanced applications for process monitoring and optimization or, so-called, soft sensors. However, the integration of advanced smart sensor systems based on image analysis into the process control system presents a complex task. To address this challenge, a modular automation concept offers a standardized interface to integrate modules. This paper presents an integration profile as a service specification that allows a plug-and-measure integration of smart visual sensors into modular plants. To verify the concept, we applied it to three different use cases. At the end, we discuss open challenges in the integration of complex analysis systems with multidimensional data streams into modular plants. 相似文献
62.
OBJECTIVE: To assess retrospectively duration of functioning and rate of complications of a totally implantable venous access system used for long-term chemotherapy. PATIENTS AND METHODS: Between 1985 and 1993, a central venous access system (Port-a-Cath) had been implanted subcutaneously for long-term chemotherapy in 1000 patients (479 males, 521 females; mean age 49 [15-86] years). Follow-up observations lasted until the end of the chemotherapy or the removal of the system. RESULTS: Mean time of functioning of the catheter system was 284 (2-1563) days. The complication rate was 12.8%: catheter infection in 4.9% and catheter thrombosis in 3.2%. A further 4.7% of patients had less common complications (malfunction, catheter dislocation, skin necrosis, catheter break or disconnection, pneumothorax). A total of 119 (11.9%) systems had to be removed because of complications. The rates of infection and of other complications were significantly lower in patients with solid tumours (2 and 4%, respectively) than in those with haematological disease (6 and 8%) (P < 0.05 for each). CONCLUSION: Totally implantable venous access systems are suitable for long-term chemotherapy and cause few complications. 相似文献
63.
We have developed a liquid chromatography-isotope dilution mass spectrometry procedure to quantify total cholesterol in serum. A particle-beam interface was used for coupling the liquid chromatograph and the mass spectrometer. After electron impact ionization the ions m/z = 386 and m/z = 389 were used for selective ion monitoring of cholesterol and the internal standard [25,26,27-(13)C]cholesterol. The sample preparation steps required for serum materials are alkaline hydrolysis and an extraction of the cholesterol into the cyclohexane phase. Imprecision for the determination of cholesterol in control materials is typically <1.0%. The deviation from the certified reference values was <0.75% for all control materials tested. A method comparison of the results obtained by this method with those obtained by gas chromatography-isotope dilution mass spectrometry for n = 28 pooled human sera derived from samples analyzed in our routine laboratory did not show differences >2.5%. 相似文献
64.
Treatment of male urethral strictures: is repeated dilation or internal urethrotomy useful? 总被引:1,自引:0,他引:1
PURPOSE: We evaluate the efficacy of repeated dilation or urethrotomy as treatment of male urethral strictures. MATERIALS AND METHODS: Between January 1991 and January 1994, 210 men with proved urethral strictures were prospectively randomized to undergo filiform dilation (106) or internal urethrotomy (104). Followup was scheduled at 3, 6, 9, 12, 24, 36 and 48 months. Dilation or internal urethrotomy was repeated at the first and second stricture recurrence. The Kaplan-Meier method was used to estimate survivor function for the treatment methods (survival time being the time to first stricture recurrence) and the log rank test was used to compare the efficacy of different treatments. RESULTS: Followup (mean 24 months, range 2 to 63) was available in 163 patients (78%). After a single dilation or urethrotomy not followed by re-stricturing at 3 months, the estimated stricture-free rate was 55 to 60% at 24 months and 50 to 60% at 48 months. After a second dilation or urethrotomy for stricture recurrence at 3 months the stricture-free rate was 30 to 50% at 24 months and 0 to 40% at 48 months. After a third dilation or urethrotomy for stricture recurrence at 3 and 6 months the stricture-free rate at 24 months was 0 (p <0.0001). CONCLUSIONS: Dilation and internal urethrotomy are useful in a select group (approximately 70% of all patients) who are stricture-free at 3 months, and of whom 50 to 60% will remain stricture-free up to 48 months. A second dilation or urethrotomy for early stricture recurrence (at 3 months) is of limited value in the short term (24 months) but of no value in the long term (48 months), whereas a third repeated dilation or urethrotomy is of no value. 相似文献
65.
66.
G. Morakile J. L. F. Kock W. van Zyl C. H. Pohl B. C. Viljoen 《Journal of the Institute of Brewing》2002,108(2):164-168
A study to differentiate commercially applied brewing yeasts selected from the culture collection of the University of the Free State from related yeasts of the genus Saccharomyces using PCR amplification and RFLP of the internal transcribed spacers region was conducted. Differentiation was dependent on the restriction enzymes used to digest the amplified rDNA. Digestion with Hae III, Cfo I, Sau 3AI and Msp I divided representatives of the genus Saccharomyces into several unique groups. With Msp I the DNA patterns for the two brewing strains were similar, but could be differentiated from Sacch. cerevisiae and other species tested. It was also possible to distinguish some members of the Saccharomyces sensu stricto group i.e. Sacch. bayanus and Sacch. pastorianus from Sacch. cerevisiae and Sacch. paradoxus using Hae III as well as Sacch. paradoxus from the other sensu stricto members using Msp I digestion. 相似文献
67.
A. Oosthuizen J. L. F. Kock B. C. Viljoen H. B. Muller P. M. Lategan 《Journal of the Institute of Brewing》1987,93(3):174-176
The cellular long-chain fatty acids of 72 strains representing 29 species of brewery yeasts were extracted by saponification and analysed as methyl esters by gas chromatography. With this method, it was possible to distinguish between Saccharomyces cerevisiae and five other groups from the brewery industry, only four hours after they were obtained from 48 h old cultures under standard conditions. This compares favourably with the 7 to 10 days for conventional methods. 相似文献
68.
C. W. Swart K. Dithebe P. W. J. van Wyk C. H. Pohl H. C. Swart E. Coetsee E. Lodolo J. L. F. Kock 《Journal of the Institute of Brewing》2013,119(1-2):15-16
We reported previously the presence of large numbers of gas bubbles inside fermenting brewing yeasts. Here we report that these bubbles deform organelles. The mechanical effects on metabolism and coding functions of yeasts, when organelles including the nucleus are deformed and severely contorted, should now be addressed. The implications of this finding on practical brewing conditions require consideration during optimization of fermentation parameters to prevent CO2 toxicity effects on fermentation performance and flavour formation. Copyright © 2013 The Institute of Brewing & Distilling 相似文献
69.
Barbara Natalie Unger Alexander Kock Hans Georg Gemünden Daniel Jonas 《International Journal of Project Management》2012
Project portfolios are vehicles for strategy implementation. Senior management should terminate projects no longer conforming to corporate strategy in order to ensure strategic fit. This paper investigates how rigorous termination of bad and troubled projects affects portfolio effectiveness and senior management's decisive role in this context. We introduce the concept of project termination quality, analyse its consequences for strategic fit and how it is affected by senior management involvement. Using a quantitative longitudinal study of a sample of project portfolios, we show that termination quality positively affects strategic fit. We also show a positive, but inverted u-shaped relationship between senior management involvement and termination quality. We conclude that there is an optimal degree of involvement, beyond which an additional involvement of senior managers results in negative effects. 相似文献