Phenotypic Noise and the Cost of Complexity

Experimental studies demonstrate the existence of phenotypic diversity despite constant genotype and environment. Theoretical models based on a single phenotypic character predict that during an adaptation event, phenotypic noise should be positively selected far from the fitness optimum because it increases the fitness of the genotype, and then be selected against when the population reaches the optimum. It is suggested that because of this fitness gain, phenotypic noise should promote adaptive evolution. However, it is unclear how the selective advantage of phenotypic noise is linked to the rate of evolution, and whether any advantage would hold for more realistic, multi-dimensional phenotypes. Indeed, complex organisms suffer a cost of complexity, where beneficial mutations become rarer as the number of phenotypic characters increases. By using a quantitative genetics approach, we first show that for a one-dimensional phenotype, phenotypic noise promotes adaptive evolution on plateaus of positive fitness, independently from the direct selective advantage on fitness. Second, we show that for multi-dimensional phenotypes, phenotypic noise evolves to a low-dimensional configuration, with elevated noise in the direction of the fitness optimum. Such a dimensionality reduction of the phenotypic noise promotes adaptive evolution and numerical simulations show that it reduces the cost of complexity.

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Synthesis, Properties, and Applications of Low-Dimensional Carbon-Related Nanomaterials

Journal of Nanomaterials ◽

10.1155/2011/685081 ◽

2011 ◽

Vol 2011 ◽

pp. 1-21 ◽

Cited By ~ 46

Author(s):

Ali Mostofizadeh ◽

Yanwei Li ◽

Bo Song ◽

Yudong Huang

Keyword(s):

Carbon Nanotubes ◽

Carbon Nanomaterials ◽

Experimental Studies ◽

Structural Features ◽

Two Dimensional ◽

One Dimensional ◽

Synthesis Properties ◽

Carbon Nanowalls ◽

Low Dimensional ◽

Carbon Encapsulated Metal Nanoparticles

In recent years, many theoretical and experimental studies have been carried out to develop one of the most interesting aspects of the science and nanotechnology which is called carbon-related nanomaterials. The goal of this paper is to provide a review of some of the most exciting and important developments in the synthesis, properties, and applications of low-dimensional carbon nanomaterials. Carbon nanomaterials are formed in various structural features using several different processing methods. The synthesis techniques used to produce specific kinds of low-dimensional carbon nanomaterials such as zero-dimensional carbon nanomaterials (including fullerene, carbon-encapsulated metal nanoparticles, nanodiamond, and onion-like carbons), one-dimensional carbon nanomaterials (including carbon nanofibers and carbon nanotubes), and two-dimensional carbon nanomaterials (including graphene and carbon nanowalls) are discussed in this paper. Subsequently, the paper deals with an overview of the properties of the mainly important products as well as some important applications and the future outlooks of these advanced nanomaterials.

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One-Dimensional Contact Pressure Distribution of Radial Tires in Motion

Tire Science and Technology ◽

10.2346/1.2137498 ◽

1995 ◽

Vol 23 (2) ◽

pp. 116-135 ◽

Cited By ~ 9

Author(s):

H. Shiobara ◽

T. Akasaka ◽

S. Kagami ◽

S. Tsutsumi

Keyword(s):

Pressure Distribution ◽

Contact Pressure ◽

Experimental Studies ◽

Rolling Resistance ◽

Leading Edge ◽

Forward Direction ◽

Contact Pressure Distribution ◽

Support Ring ◽

One Dimensional ◽

Lowered Pressure

Abstract The contact pressure distribution and the rolling resistance of a running radial tire under load are fundamental properties of the tire construction, important to the steering performance of automobiles, as is well known. Many theoretical and experimental studies have been previously published on these tire properties. However, the relationships between tire performances in service and tire structural properties have not been clarified sufficiently due to analytical and experimental difficulties. In this paper, establishing a spring support ring model made of a composite belt ring and a Voigt type viscoelastic spring system of the sidewall and the tread rubber, we analyze the one-dimensional contact pressure distribution of a running tire at speeds of up to 60 km/h. The predicted distribution of the contact pressure under appropriate values of damping coefficients of rubber is shown to be in good agreement with experimental results. It is confirmed by this study that increasing velocity causes the pressure to rise at the leading edge of the contact patch, accompanied by the lowered pressure at the trailing edge, and further a slight movement of the contact area in the forward direction.

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A Relativistic Newtonian Mechanics Predicts with Precision the Results of Recent Neutrino-Velocity Experiments

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v6i1.1824 ◽

2014 ◽

Vol 6 (1) ◽

pp. 1032-1035 ◽

Cited By ~ 1

Author(s):

Ramzi Suleiman

Keyword(s):

Null Hypothesis ◽

Experimental Studies ◽

Theoretical Models ◽

Newtonian Mechanics ◽

Speed Of Light ◽

Symmetry Principle ◽

Proposed Model ◽

Significant Difference ◽

The One ◽

Complete Collapse

The research on quasi-luminal neutrinos has sparked several experimental studies for testing the "speed of light limit" hypothesis. Until today, the overall evidence favors the "null" hypothesis, stating that there is no significant difference between the observed velocities of light and neutrinos. Despite numerous theoretical models proposed to explain the neutrinos behavior, no attempt has been undertaken to predict the experimentally produced results. This paper presents a simple novel extension of Newton's mechanics to the domain of relativistic velocities. For a typical neutrino-velocity experiment, the proposed model is utilized to derive a general expression for . Comparison of the model's prediction with results of six neutrino-velocity experiments, conducted by five collaborations, reveals that the model predicts all the reported results with striking accuracy. Because in the proposed model, the direction of the neutrino flight matters, the model's impressive success in accounting for all the tested data, indicates a complete collapse of the Lorentz symmetry principle in situation involving quasi-luminal particles, moving in two opposite directions. This conclusion is support by previous findings, showing that an identical Sagnac effect to the one documented for radial motion, occurs also in linear motion.

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Experimental Evaluation of Airlift Performance for Vertical Pumping of Water in Underground Mines

Mine Water and the Environment ◽

10.1007/s10230-021-00807-w ◽

2021 ◽

Author(s):

Parviz Enany ◽

Oleksandr Shevchenko ◽

Carsten Drebenstedt

Keyword(s):

Water Flow ◽

High Efficiency ◽

Experimental Studies ◽

Theoretical Models ◽

Injection System ◽

Experimental Investigations ◽

Flow Mode ◽

New Device ◽

Riser Pipe ◽

Airlift Pump

AbstractThis paper presents experimental studies on the optimization of air–water flow in an airlift pump. Airlift pumps use compressed gas to verticall transport liquids and slurries. Due to the lack of theoretical equations for designing and predicting flow regimes, experimental investigations must be carried out to find the best condition to operate an airlift pump at high efficiency. We used a new air injection system and different submergence ratios to evaluate the output of a simple pump for vertical displacement of water in an underground mine. The tests were carried out in a new device with 5.64 m height and 10.2 cm circular riser pipe. Three air-jacket pipes, at different gas flows in the range of 0.002–0.09 m3/s were investigated with eight submergence ratios. It was found that with the same air flow rate, the most efficient flow of water was achieved when an air jacket with 3 mm diameter holes was used with a submergence ratio between 0.6 and 0.75. In addition, a comparison of practical results with two theoretical models proposed by other investigators showed that neither was able to accurately predict airlift performance in air–water flow mode.

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Small-Scale Spectrum of a Scalar Field in Water: The Batchelor and Kraichnan Models

Journal of Physical Oceanography ◽

10.1175/jpo-d-11-025.1 ◽

2011 ◽

Vol 41 (11) ◽

pp. 2155-2167 ◽

Cited By ~ 11

Author(s):

Xavier Sanchez ◽

Elena Roget ◽

Jesus Planella ◽

Francesc Forcat

Keyword(s):

Scalar Field ◽

Thermal Gradient ◽

Theoretical Models ◽

Measured Data ◽

Small Scale ◽

Temperature Profiles ◽

One Dimensional ◽

Kraichnan Model ◽

The One ◽

Rate Of Dissipation

Abstract The theoretical models of Batchelor and Kraichnan, which account for the smallest scales of a scalar field passively advected by a turbulent fluid (Prandtl > 1), have been validated using shear and temperature profiles measured with a microstructure profiler in a lake. The value of the rate of dissipation of turbulent kinetic energy ɛ has been computed by fitting the shear spectra to the Panchev and Kesich theoretical model and the one-dimensional spectra of the temperature gradient, once ɛ is known, to the Batchelor and Kraichnan models and from it determining the value of the turbulent parameter q. The goodness of the fit between the spectra corresponding to these models and the measured data shows a very clear dependence on the degree of isotropy, which is estimated by the Cox number. The Kraichnan model adjusts better to the measured data than the Batchelor model, and the values of the turbulent parameter that better fit the experimental data are qB = 4.4 ± 0.8 and qK = 7.9 ± 2.5 for Batchelor and Kraichnan, respectively, when Cox ≥ 50. Once the turbulent parameter is fixed, a comparison of the value of ɛ determined from fitting the thermal gradient spectra to the value obtained after fitting the shear spectra shows that the Kraichnan model gives a very good estimate of the dissipation, which the Batchelor model underestimates.

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Influence of Temperature Fields on the Quality of Dried Wood Products

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1038.336 ◽

2021 ◽

Vol 1038 ◽

pp. 336-344

Author(s):

Olena Pinchevska ◽

Andriy Spirochkin ◽

Denys Zavialov ◽

Rostislav Oliynyk

Keyword(s):

Experimental Studies ◽

Wood Products ◽

Temperature Fields ◽

Drying Process ◽

Wood Moisture ◽

Adequate Model ◽

Heating And Cooling ◽

White Spots ◽

The Cost ◽

Wood Heating

The reasons of white spots appearance in the middle of oak timber are determined. These white spots reduce the cost of the lamina made of oak timbers - the front covering of floorboards. It is proposed to intensify the drying process by using oscillating drying schedules to avoid this defect. A method for calculating the duration of such drying is proposed. This method includes the peculiarities of heating and cooling periods kinetics of oak timbers with 25 mm and 30 mm thickness. The inexpediency of using the oscillation of the drying agent parameters in the range of wood moisture content below 20% has been established. An adequate model for calculating wood temperature and air humidity during wood heating and cooling periods has been developed using heat and mass transfer criteria and experimentally determined oak wood moisture conductivity coefficient. Based on the results of theoretical and experimental studies oscillating drying schedules of different thickness oak timbers are offered. Tests of the proposed schedules in industrial conditions showed no discoloration of the central layers of European oak (Quercus robur) timbers. The drying process duration was reduced by 1.5–2.4 times and energy consumption were reduced by 1.53 times.

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Evaluation of the Vertical Producing Degree of Commingled Production via Waterflooding for Multilayer Offshore Heavy Oil Reservoirs

Energies ◽

10.3390/en11092428 ◽

2018 ◽

Vol 11 (9) ◽

pp. 2428 ◽

Cited By ~ 4

Author(s):

Fei Shen ◽

Linsong Cheng ◽

Qiang Sun ◽

Shijun Huang

Keyword(s):

Heavy Oil ◽

Flow Model ◽

Dynamic Method ◽

Theoretical Models ◽

Oil Reservoirs ◽

Sweep Efficiency ◽

One Dimensional ◽

Heavy Oil Reservoirs ◽

The Difference ◽

Important Form

Recently, commingling production has been widely used for the development of offshore heavy oil reservoirs with multilayers. However, the differences between layers in terms of reservoir physical properties, oil properties and pressure have always resulted in interlayer interference, which makes it more difficult to evaluate the producing degree of commingled production. Based on the Buckley–Leverett theory, this paper presents two theoretical models, a one-dimensional linear flow model and a planar radial flow model, for water-flooded multilayer reservoirs. Through the models, this paper establishes a dynamic method to evaluate seepage resistance, sweep efficiency and recovery percent and then conducts an analysis with field data. The result indicates the following: (1) the dynamic difference in seepage resistance is an important form of interlayer interference during the commingled production of an offshore multilayer reservoir; (2) the difference between commingled production and separated production is small within a certain range of permeability ratio or viscosity ratio, but separated production should be adopted when the ratio exceeds a certain value.

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Modeling Cyclic Variability in Spark-Assisted HCCI

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2906176 ◽

2008 ◽

Vol 130 (5) ◽

Cited By ~ 34

Author(s):

C. Stuart Daw ◽

K. Dean Edwards ◽

Robert M. Wagner ◽

Johney B. Green

Keyword(s):

Control Strategies ◽

Experimental Studies ◽

Mode Switching ◽

Load Range ◽

Gasoline Engines ◽

Cyclic Variability ◽

Hcci Combustion ◽

Quantitative Understanding ◽

Low Dimensional ◽

High Degree

Spark assist appears to offer considerable potential for increasing the speed and load range over which homogeneous charge compression ignition (HCCI) is possible in gasoline engines. Numerous experimental studies of the transition between conventional spark-ignited (SI) propagating-flame combustion and HCCI combustion in gasoline engines with spark assist have demonstrated a high degree of deterministic coupling between successive combustion events. Analysis of this coupling suggests that the transition between SI and HCCI can be described as a sequence of bifurcations in a low-dimensional dynamic map. In this paper, we describe methods for utilizing the deterministic relationship between cycles to extract global kinetic rate parameters that can be used to discriminate multiple distinct combustion states and develop a more quantitative understanding of the SI-HCCI transition. We demonstrate the application of these methods for indolene-containing fuels and point out an apparent HCCI mode switching not previously reported. Our results have specific implications for developing dynamic combustion models and feedback control strategies that utilize spark assist to expand the operating range of HCCI combustion.

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