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This paper shows that Danckwerts’ law for mean residence time in a vessel with continuous and steady throughflow holds for a stochastic model based on a Markov chain for the particle spatial position, under a set of three very general conditions on the transfer probabilities. These are natural conditions and represent mass balance conditions on the transfer between spatial regions in the process. It is shown that a stochastic model for particle residence time distribution with these three conditions may describe almost any physical flow configuration, and also covers published mathematical RTD models, independent of their mathematical form or the nature of the associated boundary conditions, models for which Danckwert's law has hitherto been shown to be satisfied on a case-by-case basis. Two examples, namely those birth-death Markov chains and fluidized bed models are discussed. 相似文献
13.
Ravaja Niklas; Kallinen Kari; Saari Timo; Keltikangas-Jarvinen Liisa 《Canadian Metallurgical Quarterly》2004,10(2):120
The authors examined the effects of suboptimally presented facial expressions on emotional and attentional responses and memory among 39 young adults viewing video (business news) messages from a small screen. Facial electromyography (EMG) and respiratory sinus arrhythmia were used as physiological measures of emotion and attention, respectively. Several congruency priming effects were found. In particular, happy facial primes prompted increased (a) pleasure ratings, (b) orbicularis oculi EMG activity, (c) perceived trustworthiness, and (d) recognition memory for video messages with a positive emotional tone. Emotional and other responses to video messages presented on a small screen can be modified with suboptimal affective primes, but even small differences in the emotional tone of the messages should be allowed for. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
14.
Timo Knuutila 《Software》1992,22(3):209-221
This paper presents some basic programming strategies for Prolog programmers. The strategies are based on knowledge about the operational behaviour of the Warren Abstract Machine (WAM). The aim is to provide simple principles for making programs both faster and less space-consuming. The programming hints given are mostly local, i.e. only a single clause or procedure need be considered at a time. 相似文献
15.
In Deutschland geh?rt der Einsatz von NEDAP-Wahlcomputern in immer mehr Gemeinden zum Alltag. Durch Untersuchungen zur Sicherheit
und Manipulierbarkeit konnten Erkenntnisse gewonnen werden, mit welchen Methoden manipulierte Software in den Wahlcomputer
eingebracht und Hardwarekomponenten ausgetauscht werden k?nnen. Dadurch ist erstmals eine Beurteilung der Eignung der NEDAP-Wahlcomputer
hinsichtlich der Anforderungen an manipulationsfeste, nachvollziehbare und transparente Wahlen m?glich. 相似文献
16.
Yu Zhi Shi Xiuzhi Zhou Jian Rao Dijun Chen Xin Dong Wenming Miao Xiaohu Ipangelwa Timo 《Engineering with Computers》2021,37(2):991-1006
Engineering with Computers - The indirect and accurate determination of blast-induced rock movement has important significance in the reduction of ore loss and dilution and in the protection of... 相似文献
17.
Julius Parulek Daniel Jönsson Timo Ropinski Stefan Bruckner Anders Ynnerman Ivan Viola 《Computer Graphics Forum》2014,33(6):276-287
Molecular visualization is often challenged with rendering of large molecular structures in real time. We introduce a novel approach that enables us to show even large protein complexes. Our method is based on the level‐of‐detail concept, where we exploit three different abstractions combined in one visualization. Firstly, molecular surface abstraction exploits three different surfaces, solvent‐excluded surface (SES), Gaussian kernels and van der Waals spheres, combined as one surface by linear interpolation. Secondly, we introduce three shading abstraction levels and a method for creating seamless transitions between these representations. The SES representation with full shading and added contours stands in focus while on the other side a sphere representation of a cluster of atoms with constant shading and without contours provide the context. Thirdly, we propose a hierarchical abstraction based on a set of clusters formed on molecular atoms. All three abstraction models are driven by one importance function classifying the scene into the near‐, mid‐ and far‐field. Moreover, we introduce a methodology to render the entire molecule directly using the A‐buffer technique, which further improves the performance. The rendering performance is evaluated on series of molecules of varying atom counts. 相似文献
18.
The dynamics of 25 blood constituents in newborn calves were monitored. Eight calves were immediately removed from dams following birth. Jugular blood samples for carbohydrate determinations were taken at birth (within 2 min), 1, 3, 6, 8, 12, 18, and 24 h and every 12 h until 144 h of age. Samples for blood chemistries were taken at birth, 1, 3, 6, 12, 24, 48, 72, 120, and 144 h. Colostrum was first fed at either 1 h (group 1) or 12 h (group 2) of age. At birth, plasma glucose concentrations were lower than the plasma fructose in both groups. Plasma glucose increased substantially from birth to 24 h, whereas fructose decreased to nondetectable concentrations by 18 h. Increases in insulin were associated with time of first feeding. Serum cortisol decreased rapidly from birth to 3 h for group 1 and at 15 h for group 2. Colostrum intake resulted in increased activities of serum alkaline phosphatase, gamma-glutamyl transpeptidase, and glutamic oxaloacetic transaminase at 6 h for group 1 and at 15 h for group 2. Activities of these enzymes decreased to "normal" values after 24-h samplings for group 1. Serum glutamic pyruvic transaminase and lactate dehydrogenase increased gradually in activity over the first 24 h in both groups and decreased after 24 h for group 1. Triglycerides and cholesterol increased from birth to 24 h in both groups and continued to increase in group 1 until 144 h. Creatinine decreased and bilirubin increased from birth to 24 h in both groups. These changes indicated that the newborn calves were undergoing many adaptive changes in relation to either maintenance of homeostasis or nutrient intake. 相似文献
19.
Schwaiger Josef Hammerl Timo Florian Johannsen Leist Susanne 《Information Systems and E-Business Management》2021,19(4):1275-1320
Information Systems and e-Business Management - The digital transformation, with its ongoing trend towards electronic business, confronts companies with increasingly growing amounts of data which... 相似文献
20.
Surface resolidification experiments using a high power CO2-laser have been performed on an Al2O3ZrO2 containing 36.8 at.% ZrO2 eutectic alloy at beam velocities between 0.3 and 8 mm·s−1. The local growth rate has been measured by observation of the orientation of the microstructure using scanning electron microscopy. In the whole range of velocities, the structure is essentially a regular lamellar eutectic and the value of the growth productλ2V was found to be ≈ 9.6·10−17 m3·s−1. The measured eutectic spacings were compared with Jackson and Hunt model. Using thermophysical properties from the literature, the measured spacings were more than four times larger than the calculated ones. Assuming all parameters of the growth relationship except the diffusion coefficient to be of the right order of magnitude or to have a negligible influence, agreement is found when using a larger liquid diffusion coefficient,DL≈5·10−10m2·s−1. 相似文献