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Primary models—linear thermal inactivation kinetics The higher the initial microbial population in a food, the longer the processing/heating time at a given temperature is required to achieve a specific lethality of microorganisms. Accordingly

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] Cai H. , Zhang C. , Wu W. , Ho T. K. , Zhang Z. Modeling high integrity transport systems by formal methods , Procedia - Social and Behavioral Sciences , Vol. 138 , 2014 , pp. 729 – 737

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References [1] Bertelsen K. , Erichsen H. V. , Madsen S. F. Application of numerical models to determine lightning

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Abstract  

It is proposed to use 14 MeV neutrons tagged by the associated particle neutron time-of-flight technique (APnTOF) to identify the fillers of unexploded ordnances (UXO) by characterizing their carbon, nitrogen and oxygen contents. To facilitate the design and construction of a prototype system, a preliminary simulation model was developed, using the Geant4 toolkit. This work established the toolkit environment for (a) generating tagged neutrons, (b) their transport and interactions within a sample to induce emission and detection of characteristic gamma-rays, and (c) 2D and 3D-image reconstruction of the interrogated object using the neutron and gamma-ray time-of-flight information. Using the modeling, this article demonstrates the novelty of the tagged-neutron approach for extracting useful signals with high signal-to-background discrimination of an object-of-interest from that of its environment. Simulations indicated that an UXO filled with the RDX explosive, hexogen (C3H6O6N6), can be identified to a depth of 20 cm when buried in soil.

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Abstract  

For the very low level radioactive waste (VLLW) disposal site, it is essential to study the regional hydrogeological condition and the transportation process of nuclide in the disposal site with the engineering barrier. The candidate VLLW repository located at the confluence of two rivers in the southwest of China, which included the characters of enrichment of the rainfall, closing to the river and inhomogeneous media. Several key aspects were focused on: (1) identified the geological and hydrogeological condition and characteristic of the VLLW disposal site, and found the recharge, runoff and drainage route and the head of the groundwater, the boundary and the spatial change of the unconfined aquifer; (2) got the parameters of simulating model by the in situ pumping experiments and correlation coefficients from the soil column experiments and batch tests; (3) calibrated the model with the data of the observed observation wells; simulated the steady state flow and migration of Sr from the repository with fine-particle barrier in 300 years by application the MODFLOW and MT3D module in the Groundwater Modeling System (GMS). The result showed that the barrier was an effective measure for the management of the disposal VLLW.

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. Mathematical modeling of the hydrodynamic and dispersion phenomena , (in Czech) Brno , Vysoké ucení tehnickév Brne , 1997 . [2] Kovárík K

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. Szép J., Murinkó G., Szepesházi R. Modelling bridge substructures, (in Hungarian) Geotechnika 2009 conference , Ráckeve, Hungary, 27–29 October 2009, p. 22. Szep J. FEM — modeling of abutment, 10th Slovak Geotechnical

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Journal of Radioanalytical and Nuclear Chemistry
Authors: G. Lujanienė, P. Beneš, K. Štamberg, K. Jokšas, D. Vopalka, E. Radžiūtė, B. Šilobritienė, and J. Šapolaitė

Abstract  

Sorption–desorption behaviour of 137Cs in the Baltic Sea and the Curonian Lagoon was studied in 1997–2009 with the aim to better understand processes responsible for redistribution and sink of 137Cs in the system. Data obtained from several sampling campaigns were analyzed and short and long-term kinetic tracer experiments using natural water and bottom sediments were carried out with particles of various sizes from 0.2 to 50 μm. Samples of suspended particles and bottom sediments collected during two sampling campaigns were fractionated according to the size, and association of 137Cs with solid phase was studied using sequential extraction. The difference in 137Cs behaviour observed between expeditions in 1999 and 2001 was attributed to seasonal variations in chemical composition of suspended particles entering the system and consequent differences between the sorption (in 1999) and the desorption (in 2001) of 137Cs in sea water. Data obtained from tracer kinetic sorption experiments with 134Cs and bottom sediment fractions of different grain size were used for finding a suitable kinetic sorption model, kinetic constants and the corresponding equilibrium K d values. It has been found that the modelled data best conform to the mechanism of ion diffusion through the so-called inert layer on the surface of the sediment particles.

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From the bureaucratic model to the bureaucratic model

The post-socialist development of the Hungarian higher education

Hungarian Educational Research Journal
Authors: István Polónyi and Tamás Kozma

. For the first time, the article reviews the recognizable models of the development of higher education and their development over time, pointing out the different direction of Hungarian development ( Hrubos, 2000 ; Kozma, 2004 ; Szabó, 2014 ). It

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. Koncepcióterv. RHK-K-074/06. 2006 (kézirat). Feng – Hudson 2010 = Feng, X. T. – Hudson, J. A. 2010: Specifying the information required for rock mechanics modelling and rock engineering design. Int. J. Rock Mech. Min. Sci. Vol. 47

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