Global classical solvability in a three‐dimensional haptotaxis system modeling oncolytic virotherapy

Author(s):  
Guoqiang Ren ◽  
Bin Liu
2012 ◽  
Vol 490-495 ◽  
pp. 2667-2671
Author(s):  
Jing Wang

The article introduces the necessity and superiority of development of CAED. It elaborates the framework and composition of the knowledge repository of CAED system and puts forward the opinion of three-dimensional Man-machine system modeling, in which the crucial elements and methods of system modeling are stressed. Based on all these ideas, the structural framework of CAED system is presented


Author(s):  
Ghislaine Ngo Boum ◽  
Rodolfo Bontempo ◽  
Isabelle Trébinjac

High accuracy simulation of compressor surge origin and growth is an important challenge for designers of systems using compressors likely to develop that severe instability. Indeed, understanding its driving phenomena, which can be system dependent, is necessary to build an adequate strategy to avoid or control surge emergence. Computational fluid dynamics (CFD) simulations, commonly used to explore flow in the compressor, need then to be extended beyond the compressor as surge is a system scale instability. To get an insight on the path to surge and through surge cycles, a reliable alternative to full three-dimensional (3D) system modeling is used for a turbocharger compressor inserted in an experimental test rig. The air flow in the whole circuit, is modeled with a one-dimensional (1D) Navier Stokes approach which is coupled with a 3D unsteady RANS modeling of the 360 deg air flow in the centrifugal compressor including the volute. Starting from an initial stable flow solution in the system, the back-pressure valve is progressively closed to reduce the massflow and trigger the instability. An entire deep surge loop is simulated and compared with good agreement with the experimental data. The existence of a system-induced convective wave is revealed, and its major role on surge inception at diffuser inlet demonstrated.


Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1838 ◽  
Author(s):  
Krzysztof Sowiżdżał ◽  
Tomasz Słoczyński ◽  
Anna Sowiżdżał ◽  
Bartosz Papiernik ◽  
Grzegorz Machowski

This paper presents the results of a research project aimed at evaluating the unconventional natural gas potential of the autochthonous Miocene sediments in the Polish part of the Carpathian Foredeep. The primary objective of the study was to re-evaluate the biogenic gas generation system within Miocene sediments, paying special attention to unconventional gas resources accumulated in tight mudstone formations. The four-dimensional (4D) petroleum system modeling method (PetroMod software) was used to reconstruct the basin geometry and three-dimensional (3D) evolution through a geological timescale, in particular the progress of gas generation, migration, and accumulation processes, as well as their consequences for gas exploration and development. Special attention was paid to the dynamics of gas generation processes and the advancement of sediment compaction and their time dependence, as well as to the progress and outcomes of gas migration and accumulation processes. The results indicate significant potential for unconventional gas accumulations in mudstone reservoirs. However, part of the biogenic gas resources occurs in a dispersed form. Analysis of the dynamics of biogenic gas generation and accumulation conducted on a basin scale and within particular sedimentary complexes and depth intervals allowed an indication of the premises regarding the most favorable zones for mudstone–claystone reservoir exploration.


2010 ◽  
Vol 156-157 ◽  
pp. 1497-1500 ◽  
Author(s):  
Meng Qi Li ◽  
Dong Ying Li

In order to reduce the work of repeated nad iterative of process model for manufacturing system, the paper proposed the establishment of three-dimensional "product - process - property" of the modeling methods with matrix mapping technology and mapped products, function, performance, process to model of production system according to the steps. Production system modeling of light-box as a case to detail description of production systems and process modeling. The modeling method with convenience, comprehensive, integrated, inheritable, and sometimes with large amount of calculation.


Author(s):  
Vishwas Verma ◽  
Gursharanjit Singh ◽  
A. M. Pradeep

Abstract Multi-spool compression systems are characterized by two or more compressor stages running at different rotational speeds. The response of an individual component can be different from an integrated system. Limiting operating conditions such as choke and stall points could have substantially different effects. The present paper explores the interactions and coupling significance between different stages of a multi-spool compression system. Further, an attempt is made by modifying the shape of the inter-compressor duct (ICD) to improve the system performance. The multi-spool system in this study comprises of the NASA stage 67 as the fan followed by in-house core and bypass ducts and a single stage booster. It is observed that the flow pattern in an ICD is entirely different in stand-alone modeling than in the integrated system modeling, owing to fan wakes and booster upstream influences. The booster performance is dependent on the duct exit flow pattern. The shape of the baseline ICD is tailored to reduce extra losses which is generated due to reduction in the length of the ICD and hence making the system more compact. It is shown that the shape tailoring optimization of ICD done independently result in a significant improvement in the duct exit flow pattern and hence an improvement in the booster performance. However, this gain in the performance is reduced to marginal values for an integrated system. This happens due to a strong coupling of the ICD flow pattern with the fan wakes and highly three dimensional nature of the ICD flow pattern. Therefore, it is found that component level optimization may not give rise to an equivalent system-level improvement.


Author(s):  
John S. Brader ◽  
Nathan R. Trevett ◽  
David N. Rocheleau

Actuation and modeling for drive-by-wire applications are discussed. Previous work in advanced actuation for two automotive systems, active suspension and camless engines, is surveyed, outlining the major advancements throughout the previous decade. More recent research in these areas is discussed and focuses on recent improvements to system modeling and design. Specifically, a four-corner suspension model and a piezoelectric piloted hydraulic actuator for engine valve actuation are introduced. The four-corner suspension model addresses the three-dimensional parameters associated with active suspension design and improves upon the accepted quarter-car model. The piezoelectric based camless engine actuator is introduced as the next generation of camless engine actuation systems and addresses control issues through the relationship between input voltage and piezoelectric displacement.


Author(s):  
Brian Smith ◽  
Cristina Amon

The performance of pyroelectric infrared detectors is directly related to the ability of the sensor material to retain infrared energy (heat) incident from the source and to react fast to changing heat loads. This leads to a complicated, three dimensional, transient thermal models when many detectors are assembled into an infrared focal plane array (IRFPA) for thermal imaging. Adjacent pixels and the underlying substrate conduct heat away from the sensor material and add thermal mass to the system. This paper describes efforts and drawbacks in deriving a system model to capture thermal phenomena in a candidate IRFPA. Of particular interest is the tradeoff between cumbersome finite element models (long solve time, complicated meshes) and a reduced-size RC network circuit model that is simple to solve and integrate with the electrical design but may not capture the full thermal behavior of the system adequately. The thermal models are cast in terms of the operating principles of pyroelectric devices to describe a full electrical-thermal system model that adapts existing literature in the field to the specific system described in this work.


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