scholarly journals NECESSARY CONDITIONS FOR THE ADEQUACY OF ECONOMIC AND MATHEMATICAL MODELS ON RIVER TRANSPORT

2020 ◽  
pp. 171-179
Author(s):  
Alexander Y. Platov ◽  
Yury I. Platov
Keyword(s):  
Mathematical Models ◽  
Transport Process ◽  
Necessary Conditions ◽  
Specific Model ◽  
Transport Processes ◽  
Fleet Planning ◽  
River Transport ◽  
Building Models ◽  
Traditional Approaches

One of the obvious conditions for the applicability of economic and mathematical models is their adequate reflection of transport processes. The issue of adequacy should be decided separately for each specific model. However, in the case of modeling for the river fleet, we can talk about the existence of traditional approaches to building models that are outdated and lead to inadequacy of all such models. It is shown that the proposed models do not fully reflect the properties of the transport process, and, therefore, their use in practice can lead to significant errors in the planning of the fleet. The analysis of typical errors in the models construction for the fleet planning is given.

scholarly journals Sub-Diffusive Dynamics Lead to Depleted Particle Densities Near Cellular Borders

2018 ◽  
Author(s):  
William R. Holmes
Keyword(s):  
Particle Density ◽  
Specific Model ◽  
Transport Processes ◽  
Generalized Langevin Equation ◽  
Diffusive Motion ◽  
Protein Activation ◽  
Cellular Environment ◽  
Anomalous Particle ◽  
Canonical Type ◽  
Different Characteristics

AbstractIt has long been known that the complex cellular environment leads to anomalous motion of intracellular particles. At a gross level, this is characterized by mean squared displacements that deviate from the standard linear profile. Statistical analysis of particle trajectories has helped further elucidate how different characteristics of the cellular environment can introduce different types of anomalousness. A significant majority of this literature has however focused on characterizing the properties of trajectories that do not interact with cell borders (e.g. cell membrane or nucleus). Numerous biological processes ranging from protein activation to exocytosis however require particles to be near a membrane. This study investigates the consequences of a canonical type of sub-diffusive motion, Fractional Brownian Motion (FBM), and its physical analogue Generalized Langevin Equation (GLE) Dynamics, on the spatial localization of particles near reflecting boundaries. Results show that this type of sub-diffusive motion leads to the formation of significant zones of depleted particle density near boundaries, and that this effect is independent of the specific model details encoding those dynamics. Rather these depletion layers are a natural and robust consequence of the anti-correlated nature of motion increments that is at the core of FBM / GLE dynamics. If such depletion zones are present, it would be of profound importance given the wide array of signaling and transport processes that occur near membranes. If not, that would suggest our understanding of this type of anomalous motion may be flawed. Either way, this result points to the need to further investigate the consequences of anomalous particle motions near cell borders from both theoretical and experimental perspectives.

scholarly journals Evaluation of Transport Processes Quality with Servqual and TUL Methods

2018 ◽  
Vol 9 (2) ◽  
pp. 61-72
Author(s):  
Aleksander Sładkowski ◽  
Maria Cieśla ◽  
Bartosz Krupa
Keyword(s):  
Service Provider ◽  
Transport Process ◽  
Transport Processes ◽  
Quality Of Services ◽  
Quality Level ◽  
Comparison Of Methods ◽  
Logistics Service ◽  
Scientific Goal ◽  
Logistics Service Provider

Abstract The theoretical part of this article presents knowledge of selected methods used to study the quality level of basic processes. Authors paid particular attention to the Servqual method, which shows the differences that exist between the perceived and delivered quality of services provided by enterprises and the TUL method. The research part will show the Servqual and TUL analysis based on the processes of the existing transport company. The article is based on well-known methodology of Servqual and TUL analysis, which was adjusted to observation of transport processes of logistics service provider. The main scientific goal of the paper was to examine the effectiveness of the methodology used on the example of a transport company and comparison of methods utility. The improvement of the transport process will increase the level of customer satisfaction, and this is the first step to increase the number of transport orders received.

Dependence of pulmonary prostaglandin metabolism on carrier-mediated transport processes

1977 ◽  
Vol 232 (4) ◽  
pp. E382-E387 ◽  
Author(s):  
L. Z. Bito ◽  
R. A. Baroody ◽  
Mary E. Reitz
Keyword(s):  
Transit Time ◽  
Transport Process ◽  
Transport Processes ◽  
Systemic Effects ◽  
Effective Inhibitor ◽  
Rat Lung ◽  
Carrier Mediated Transport ◽  
The Difference ◽  
Pulmonary Transit Time ◽  
Bromcresol Green

Inhibitors of prostaglandin (PG) transport (probenecid, indomethacin, or bromcresol green) were found to eliminate the difference between the pulmonary transit time of 3H and 14C when [3H]PGF2alpha and E114C]sucrose were injected as a single intra-arterial bolus into the isolated perfused rat lung. Similar results were obtained with PGE1. The transit time of [3H]PGA1 was not significantly different from that of [14C]sucrose even in the absence of an inhibitor. These inhibitors increased the amount of [3H]PGF2alpha or [3H]PGE1 and decreased the amount of [3H]PG metabolites found in the venous effluent: these agents also inhibited the pulmonary metabolism of continously infused, nonradioactive PGF2alpha. One of the three inhibitors, bromcresol green, was shown not to be an effective inhibitor of PG metabolism in cell-free preparations of rat lung homogenates. These results indicated that under normal conditions, PG's are rapidly transported into intracellular compartment(s) where they are metabolized. Inhibition of this transport process prevents rapid access of PG's to the cytoplasmic enzymes and therefore inhibits pulmonary PG metabolism. This implies that inhibitors of PG transport, including anti-inflammatory organic acids, and some PG antagonists, metabolites, and analogues, can be expected to inhibit the pulmonary metabolism of PG's and thus could potentiate the systemic effects endogenous or exogenous PG's.

scholarly journals Simulation Models in Testing Reliability of Transport Process

2016 ◽  
Vol 37 (1) ◽  
pp. 203-230 ◽  
Author(s):  
Marianna Jacyna ◽  
Jolanta Żak
Keyword(s):  
Transport Process ◽  
Service Providers ◽  
Simulation Models ◽  
Quality Parameters ◽  
Transport Processes ◽  
Transport Network ◽  
Conflict Situations ◽  
Network Equipment ◽  
System Input ◽  
Complex Decision Making

Abstract The paper touches the problem of applying simulation models to assess the reliability of services in transport networks. Investigation of the transport processes in terms of their reliability is a complex decision-making task. The paper describes a method for assessing the reliability of transport process on the base of the criterion of minimizing the normalized lost time of vehicles. The time is wasted in a result of conflict situations occurring in the transport network during the transport process. The study includes stochastic distributions of system input. It enables studying the quality parameters of the transport network equipment, including service providers working under different workload and all kinds of disturbances. The method uses simulation models. Simulation studies were performed with Java Modelling Tools.

Experiment and Theoretical Study on Thermal Transport Process in Nano-Sized Copper Film

2013 ◽  
Vol 756-759 ◽  
pp. 108-111
Author(s):  
Fan Da Zeng ◽  
Ya Ping Han ◽  
Jin Xin Wang ◽  
Shao Ze Wang
Keyword(s):  
Thin Film ◽  
Finite Difference Method ◽  
Thermal Transport ◽  
Transport Process ◽  
Theoretical Study ◽  
Copper Film ◽  
Transport Processes ◽  
Time Resolved ◽  
Copper Thin Film ◽  
Glass Substrates

nanosized copper thin film was prepared on glass substrates by magnetron sputtering. 800 nm pump and 400nm probe technique were used to measure time-resolved reflectivity of copper thin film, and the heat transport processes of copper film were experimentally studied. Thermal transport processes in the copper film were numerically simulated by using Parabolic Two-Step (PTS) model with Finite Difference method. The result of the PTS model can well evaluate the measure date.

Sensitivity of global energy confinement to the boundary condition due to coupling of MHD and transport processes

1994 ◽  
Vol 51 (2) ◽  
pp. 201-210 ◽  
Author(s):  
X. H. Deng ◽  
C. Zhang ◽  
Y. P. Huo ◽  
J. F. Wang ◽  
Shui Wang
Keyword(s):  
Boundary Condition ◽  
Transport Process ◽  
Transport Processes ◽  
Global Energy ◽  
Energy Confinement ◽  
One Dimensional ◽  
Mhd Instabilities ◽  
Transport Condition ◽  
Edge Temperature ◽  
Plasma Profile

MHD instabilities are governed by the transport-determined plasma profiles, and the transport process is affected in turn by the instabilities. Using a one-dimensional code, we have investigated the inter-relationship between instabilities, transport and plasma profile in a tokamak discharge. The results show that the global energy confinement becomes strongly dependent on the boundary transport condition owing to strong coupling between them, and a higher edge temperature would ensure a higher core temperature and hence greater global energy confinement.

scholarly journals Safety of transport processes of the trucks determined by reliability.

2015 ◽  
Vol 2015 (2) ◽  
pp. 88-92
Author(s):  
Владимир Самусенко ◽  
Vladimir Samusenko ◽  
Наталия Сакович ◽  
Nataliya Sakovich ◽  
Евгений Христофоров ◽  
...  
Keyword(s):  
Probability Theory ◽  
Mathematical Models ◽  
Russian Federation ◽  
Transport Processes ◽  
The Russian Federation

In article questions of safety of transport processes on roads of the Russian Federation of the vehicles caused by reliability are considered. Authors considered activities on safety of the movement at design stages of the created car. For a solution authors used mathematical models on the basis of probability theory.

scholarly journals FIELD OBSERVATION OF FINE SEDIMENT TRANSPORT PROCESS AROUND RIVER MOUTHS IN NORTH WESTERN JAVA ISLAND, INDONESIA

2018 ◽  
pp. 77
Author(s):  
Yasuyuki Nakagawa ◽  
A. Bagyo Widagdo ◽  
Masayuki Banno ◽  
Gugum A. Gumbira ◽  
Taichi Kosako ◽  
...  
Keyword(s):  
Transport Process ◽  
River Discharge ◽  
Weather Condition ◽  
Fine Sediment ◽  
Transport Processes ◽  
Fluid Mud ◽  
Muddy Sediment ◽  
Sedimentary System ◽  
River Mouths ◽  
North Western

Understanding of transport processes of discharged sediment through the river in coastal area is crucial for prediction of coastal bathymetry evolution. In case that fine sediment is dominant in sedimentary system, the transport process becomes complicate with the formation of fluid mud, which may be an important role on the transport and distribution of muddy sediment. The aim of this study is to elucidate the fine sediment dynamics, which may have a key role on the deformation of the deltaic topography around the estuary, in a tropical climate environment where experiences apparent seasonal variation of river discharge due to the wet and dry weather condition.

Flow-dependent transport processes: filtration, absorption, secretion

1982 ◽  
Vol 243 (1) ◽  
pp. F1-F11 ◽  
Author(s):  
F. S. Wright
Keyword(s):  
Flow Rate ◽  
Transport Process ◽  
Driving Force ◽  
Transport Processes ◽  
Sodium Absorption ◽  
Flow Rates ◽  
Proximate Cause ◽  
Flow Dependence ◽  
Dependent Change ◽  
Dependent Transport

To define aspects common to different flow-dependent renal transport processes, four examples of such transport processes are considered: glomerular filtration, distal potassium secretion, ascending limb sodium absorption, and proximal fluid absorption. For each example the phenomenon of flow dependence is documented and the mechanism underlying this behavior is explored. Two general types of flow dependence are recognized: dissipative and generative. The first three processes are examples of dissipative flow dependence. In each a flow-sensitive component of the driving force for transport is generated upstream from the site of transport, the transport process tends to dissipate its driving force, and higher flow rates tend to maintain the driving force. The fourth process considered is an example of generative flow dependence. In this case the flow-sensitive component of the driving force is generated within the transporting segment. Flow affects the transport process by preventing dissipation of the driving force, as in the first three cases. Both types of processes can be expected to be more flow dependent in some lower range of flow rate and to be less flow dependent in some higher range of flow rate. This is because the proximate cause of a change in transport, a flow-dependent change in driving force is larger for a given change of flow rate when flow rates are relatively slow.

Carrier Transport Mechanism in Single Crystalline Organic Semiconductor Thin Film Elucidated by Visualized Carrier Motion

2016 ◽  
Vol 16 (4) ◽  
pp. 3388-3393
Author(s):  
Kohei Matsubara ◽  
Kentaro Abe ◽  
Takaaki Manaka ◽  
Mitsumasa Iwamoto
Keyword(s):  
Thin Film ◽  
Temperature Dependence ◽  
Transport Process ◽  
Carrier Transport ◽  
Second Harmonic ◽  
Potential Drop ◽  
Transport Processes ◽  
Time Resolved ◽  
Single Crystalline ◽  
Injection Process

Time-resolved microscopic second harmonic generation (TRM-SHG) measurement was conducted to evaluate temperature dependence of the anisotropic carrier transport process in 6,13-Bis(triisopropylsilylethynyl) (TIPS) pentacene single crystalline domains for two orthogonal directions. Enhancement of the electric field induced SHG (EFI-SHG) signal at the electrode edge at low temperature suggests the presence of potential drop in the injection process. We directly evaluated temperature dependence of the carrier mobility by taking into account the potential drop, and concluded that the Marcus theory is appropriate to interpret the carrier transport in anisotropic TIPS pentacene thin film. TRM-SHG method is a facile and effective way to directly visualize transport process in anisotropic materials and to evaluate injection and transport processes simultaneously.

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