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81.
《Drying Technology》2007,25(1):85-95
Artificial neural network (ANN) models were developed for the prediction of transient moisture loss (ML) and solid gain (SG) in osmotic dehydration of fruits using process kinetics data from the literature. ANN models for ML and SG were developed based on data over a broad range of operating conditions and ten common processing variables: temperature and concentration of osmotic solution, immersion time, initial water and solid content of the fruit, porosity, surface area, characteristic length, solution-to-fruit mass ratio, and agitation level. The trained models were able to accurately predict the outputs with associated regression coefficients (r) of 0.96 and 0.93, respectively, for ML and SG. These ANN models performed much better than those obtained from linear multivariate regression analysis. The large number of process variables and their wide ranges considered along with their easy implementation in a spreadsheet make them very useful and practical for process design and control. 相似文献
82.
Manabu Ishitobi Takeshi Myoi Koji Soshin Eiji Hiraki Mutsuo Nakaoka 《Electrical Engineering in Japan》2005,153(3):79-87
This paper presents a single lossless inductive snubber‐assisted ZCS‐PFM series resonant DC‐DC power converter with a high‐frequency high‐voltage transformer link for industrial‐use high‐power magnetron drive. The current flowing through the active power switches rises gradually at a turned‐on transient state with the aid of a single lossless snubber inductor, and ZCS turn‐on commutation based on overlapping current can be achieved via the wide range pulse frequency modulation control scheme. The high‐frequency high‐voltage transformer primary side resonant current always becomes continuous operation mode, by electromagnetic loose coupling design of the high‐frequency high‐voltage transformer and the magnetizing inductance of the high‐frequency high‐voltage transformer. As a result, this high‐voltage power converter circuit for the magnetron can achieve a complete zero current soft switching under the condition of broad width gate voltage signals. Furthermore, this high‐voltage DC‐DC power converter circuit can regulate the output power from zero to full over audible frequency range via the two resonant frequency circuit design. Its operating performances are evaluated and discussed on the basis of the power loss analysis simulation and the experimental results from a practical point of view. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 153(3): 79–87, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20126 相似文献
83.
84.
Evaluation of rainfall networks using entropy: II. Application 总被引:2,自引:0,他引:2
This paper, the second in the series, applies the entropy approach to space and time evaluation of rainfall networks in Louisiana. The evaluation is made for five sampling intervals: daily, 2-day, weekly, monthly, and yearly, and for two separate seasons. In each case, the best combination of raingages is suggested and the lines of equal information (isoinformation contours) are constructed showing the areas of greater or less information transfer. The isoinformation lines are especially suitable in decisions concerning the expansion of the existing network or deleting the unnecessary raingages. 相似文献
85.
A new evaluation model for SK combinator expressions is presented and used as a basis for the design of a novel processor. The resulting machine architecture resembles a dataflow ring, but executions are constrained to be fully lazy. An automatic dynamic load sharing mechanism for a distributed multiprocessor architecture is suggested, and initial simulation results are presented. 相似文献
86.
Ioannis D. Moscholios Michael D. Logothetis 《International Journal of Communication Systems》2006,19(1):67-93
We consider a single link loss system of quasi‐random input, described by the Engset multirate loss model (EnMLM). Blocked calls may once reattempt to be connected to the system requiring less bandwidth; then the system is described by the single retry model for finite sources (f‐SRM). The EnMLM and the f‐SRM are extended with the single threshold finite source model (f‐STM), where calls may attempt to be connected to the system with less bandwidth requirements, according to the link occupancy, before blocking occurs. We focus on CBP equalization in the EnMLM, f‐SRM and f‐STM, under the bandwidth reservation (BR) policy. For this analysis, we apply two approximate methods, the Roberts' method and the method of reverse transition rates (RTR), which lead to a recursive CBP calculation. We evaluate the accuracy of the above models under the BR policy by comparing the analytical with simulation CBP results, based on the relative approximation errors (RAE). The results are highly satisfactory because they show that the proposed models (formulas) lead to small RAE. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
87.
Cu ion co-ordination-location in zeolites of MFI, erionite, mordenite matrices has been determined and the activity of the individual Cu sites compared for NO decomposition and its selective reduction by hydrocarbons or ammonia. It appears that Cu ions in the vicinity of one framework Al (site II), able to form stable Cu+-dinitrosyl complexes, and abundant in MFI structure, are responsible for high activity in NO decomposition. The Cu ions neighbouring two framework Al atoms (site I), and forming mostly mononitrosyl complexes, which dominate in erionite structure, provide a high activity in selective reduction of NO. 相似文献
88.
Wu Songping 《Microelectronics Journal》2007,38(1):41-46
The preparation of ultra fine nickel-copper bimetallic powder with two-stage chemical reduction method was investigated. Reductive sugar and hydrazine hydrate were employed as reducing agent in different reductive stage, respectively. Reaction of CuSO4·5H2O with reductive sugar at 70 °C gives cuprous oxide and copper particles, then as-prepared mixture and nickelous hydroxide were reduced by hydrazine hydrate, and nickel-copper powder having excellent dispersibility was prepared. Influences of nickel added on composition and dispersibility of powder were studied. TG/DTG/DTA of nickel-copper powder, which is stable in room temperature, were discussed with thermal analyzer. Relation of nickel content to oxidation temperature was investigated. Ni-Cu bimetallic powder particles have a fully coated structure when nickel content is up to 30%. As-prepared nickel-copper powder was applied in base metal electrode-multilayer ceramic capacitor (BME-MLCC). The end termination has high adhesion force, fairly good densification, low resistivity, excellent solderibility behavior and resistance behavior to soldering. 相似文献
89.
半导体激光器到单模光纤耦合技术的现状及发展趋势 总被引:1,自引:0,他引:1
简要阐述了半导体激光器到单模光纤的耦合损耗来源,详细介绍和分析了耦合技术的发展和现状,并探讨了耦合技术的发展趋势。 相似文献
90.
货运调车场减速顶噪声及治理的探讨 总被引:1,自引:0,他引:1
铁路货物运输枢纽的调车场中,驼峰调车是主要的调车手段,为提高生产效率和确保安全,沿驼峰下滑道布置的减速器(减速闸,减速顶)的噪声是调车场噪声的主要声源之一,本文通过对昆明东站铁路降噪工程的观测试验项目,探讨了减速顶噪声的特性及治理措施。 相似文献