A simple model of optimal territory size for drift-feeding fish

1987 ◽  
Vol 65 (2) ◽  
pp. 270-276 ◽  
Author(s):  
James W. A. Grant ◽  
David L. G. Noakes
Keyword(s):  
Simple Model ◽  
Territory Size ◽  
Time Constraints ◽  
Food Density ◽  
Daily Ration ◽  
Natural Manner ◽  
Drift Feeding ◽  
Feeding Territory ◽  
The Cost ◽  
Simple Models

A simple model of optimal feeding-territory size is developed for drift-feeding fish by modifying Hixon's (M. A. Hixon. 1980. Am. Nat. 115: 510–530) model for energy maximizers. Our model predicts that territory size should vary directly with food density when the fish is subject to time constraints, and directly with intruder pressure when the fish is subject to processing constraints. These unique predictions arise because any food not immediately eaten is carried downstream out of the territory. Our model also predicts that territory size should vary inversely with intruder pressure when the fish is subject to time constraints, and inversely with food density when the fish is subject to processing constraints. The qualitative predictions of the model are not affected by changes in the shape of the cost or benefit curves, unlike other simple models. A review of studies of salmonid territory size indicates that most are inadequate tests of the model because (i) food was not presented in a natural manner, (ii) ration levels were not controlled at levels that were clearly above or below a maximum daily ration, and (iii) the confounding effects of intruder pressure were not controlled. Future experiments will have to incorporate these factors to distinguish between the competing predictions posed by this and previous models.

On simple, weak and strong models of propositional calculi

1973 ◽  
Vol 74 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Ronald Harrop
Keyword(s):  
Simple Model ◽  
Propositional Calculus ◽  
Finite Model ◽  
Model Property ◽  
Finite Model Property ◽  
Finite Structure ◽  
Propositional Calculi ◽  
Simple Models

In this paper we will be concerned primarily with weak, strong and simple models of a propositional calculus, simple models being structures of a certain type in which all provable formulae of the calculus are valid. It is shown that the finite model property defined in terms of simple models holds for all calculi. This leads to a new proof of the fact that there is no general effective method for testing, given a finite structure and a calculus, whether or not the structure is a simple model of the calculus.

Feature-Based Test Focus Selection Technique Using Classes Connections Weight

2016 ◽  
Vol 7 (1) ◽  
pp. 33-44 ◽  
Author(s):  
Iyad Alazzam ◽  
Mohammed Akour ◽  
Shadi Banitaan ◽  
Feras Hanandeh
Keyword(s):  
Time Constraints ◽  
Integration Testing ◽  
Development Cost ◽  
Static And Dynamic Analysis ◽  
Source Tracing ◽  
System User ◽  
Testing Cost ◽  
Feature Based ◽  
Good Mutation ◽  
The Cost

Testing could cost more than fifty percent of all development cost, particularly integration testing consumes around eighty percent of testing cost. Integration testing aims to discover errors in the connections among classes which are collaborate and communicate in order to provide specific services. Though, testing all connections among classes is impractical because of the cost, effort and time constraints. Test focus selection might help testers to concentrate on the main and vital connections among classes which it could be the most error prone ones. The authors proposed approach amalgamates the static and dynamic analysis in order to detect, trace, and weight the connections among classes through method level communications. Their approach harnessed an open source tracing tool (MUTT). The MUTT allows them to return all the methods in all classes that have been called respecting to any specific feature which has triggered by the system user. The experimental results reveal how the proposed approach achieves good mutation testing score on the systems under study.

scholarly journals Fast and simple model for atmospheric radiative transfer

2010 ◽  
Vol 3 (3) ◽  
pp. 2225-2273
Author(s):  
F. C. Seidel ◽  
A. A. Kokhanovsky ◽  
M. E. Schaepman
Keyword(s):  
Remote Sensing ◽  
Simple Model ◽  
Radiative Transfer ◽  
Solar Zenith Angle ◽  
Trade Off ◽  
Quantitative Remote Sensing ◽  
Reflectance Factor ◽  
Atmospheric Radiative Transfer ◽  
The Cost ◽  
Airborne Sensors

Abstract. Radiative transfer models (RTMs) are of utmost importance for quantitative remote sensing, especially for compensating atmospheric perturbation. A persistent trade-off exists between approaches that prefer accuracy at the cost of computational complexity, versus those favouring simplicity at the cost of reduced accuracy. We propose an approach in the latter category, using analytical equations, parameterizations and a correction factor to efficiently estimate the effect of molecular multiple scattering. We discuss the approximations together with an analysis of the resulting performance and accuracy. The proposed Simple Model for Atmospheric Radiative Transfer (SMART) decreases the calculation time by a factor of more than 25 in comparison to the benchmark RTM~6S on the same infrastructure. The approximative computation of the atmospheric reflectance factor by SMART has an uncertainty ranging from about 5% to 10% for nadir spaceborne and airborne observational conditions. The combination of a large solar zenith angle (SZA) with high aerosol optical depth (AOD) at low wavelengths lead to uncertainties of up to 15%. SMART can be used to simulate the hemispherical conical reflectance factor (HCRF) for spaceborne and airborne sensors, as well as for the retrieval of columnar AOD.

Design of seal ring with rectangular grooves for gas isolation in Nanoimprint Lithography

2018 ◽  
Vol 233 (3) ◽  
pp. 1079-1086
Author(s):  
Peng Wei ◽  
Ma Liuhong ◽  
Li Mengke ◽  
Zhong Yinghui ◽  
Shangguan Lei ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Simple Model ◽  
Nanoimprint Lithography ◽  
Compressed Air ◽  
Comsol Multiphysics ◽  
Width Ratio ◽  
Seal Ring ◽  
The Cost ◽  
The Relationship

The prominent seal ring has been studied to prevent the compressed air from entering the enclosed area of the mold and the wafer and protect pattern in Compressional Gas Cushion Press Nanoimprint Lithography (CGCP NIL). In this paper, a non-salient seal ring with rectangular grooves was proposed to replace the prominent one, which achieved the same effect. The relationship between the width of seal ring and other three factors—the contact surface properties, the height of printed liquid, and the contact angle—was also investigated. The non-salient seal ring can be effective in sealing out the compressed air, on condition that the seal ring was wide enough. Besides, the width to meet the requirements reduced significantly, with increasing the roughness. Furthermore, the rectangular grooves etched on the seal ring can increase its surface roughness and the depth–width ratio was larger, surface roughness was bigger. Owing to the presence of rectangular grooves, smaller width was required to reach the same effect of leak-proof in the process. Besides, a simple model of COMSOL Multiphysics was established to verify the correctness of proposal. This work will greatly reduce the cost of the mold and guide the production of the mold in CGCP NIL.

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