Source-Based Minimum Cost Multicasting: Intermediate-Node Selection with Potentially Low Cost

2005 ◽  
pp. 808-819 ◽  
Author(s):  
Gunu Jho ◽  
Moonseong Kim ◽  
Hyunseung Choo
Keyword(s):  
Low Cost ◽  
Minimum Cost ◽  
Node Selection ◽  
Intermediate Node

Efficiency of uphill locomotion in nocturnal and diurnal lizards

1996 ◽  
Vol 199 (3) ◽  
pp. 587-592 ◽  
Author(s):  
C Farley ◽  
M Emshwiller
Keyword(s):  
Body Mass ◽  
Low Cost ◽  
Minimum Cost ◽  
Mechanical Work ◽  
Energetic Cost ◽  
Cost Of Transport ◽  
Unit Distance ◽  
Cost Of Locomotion ◽  
Average Body Mass ◽  
Average Body

Nocturnal geckos can walk on level ground more economically than diurnal lizards. One hypothesis for why nocturnal geckos have a low cost of locomotion is that they can perform mechanical work during locomotion more efficiently than other lizards. To test this hypothesis, we compared the efficiency of the nocturnal gecko Coleonyx variegatus (average body mass 4.2 g) and the diurnal skink Eumeces skiltonianus (average body mass 4.8 g) when they performed vertical work during uphill locomotion. We measured the rate of oxygen consumption when each species walked on the level and up a 50 slope over a range of speeds. For Coleonyx variegatus, the energetic cost of traveling a unit distance (the minimum cost of transport, Cmin) increased from 1.5 to 2.7 ml O2 kg-1 m-1 between level and uphill locomotion. For Eumeces skiltonianus, Cmin increased from 2.5 to 4.7 ml O2 kg-1 m-1 between level and uphill locomotion. By taking the difference between Cmin for level and uphill locomotion, we found that the efficiency of performing vertical work during locomotion was 37 % for Coleonyx variegatus and 19 % for Eumeces skiltonianus. The similarity between the 1.9-fold difference in vertical efficiency and the 1.7-fold difference in the cost of transport on level ground is consistent with the hypothesis that nocturnal geckos have a lower cost of locomotion than other lizards because they can perform mechanical work during locomotion more efficiently.

scholarly journals Computer-Optimized Weaning Food Blends

1995 ◽  
Vol 16 (3) ◽  
pp. 1-20 ◽  
Author(s):  
R. E. Hayes ◽  
J. M. Mwale ◽  
P. Tembo ◽  
J. I. Wadsworth
Keyword(s):  
Linear Programming ◽  
Amino Acid ◽  
Total Energy ◽  
Essential Amino Acid ◽  
Protein Quality ◽  
Low Cost ◽  
Minimum Cost ◽  
Weaning Food ◽  
Weaning Foods ◽  
Different Seasons

This computerized linear programming study was performed to formulate low-cost, commercially processed, blended weaning foods, and even less expensive, home-prepared, blended wearing foods, with excellent energy and protein value for use in areas of Lusaka, Zambia, where the risk of malnutrition is high. Ingredient input information included proximate and essential amino acid analyses, into-the-blend costs, and factors for gastrointestinal absorption of proteins and total energy. For most computed mixtures, the minimum cost at selected levels of absorbed protein quality was optimized. Formulations were determined, with calculated cost and nutritional parameters, using only mother-favoured ingredients or, alternatively, selections from among all listed market ingredients; fat versus fat plus sugar as concentrated energy; for different seasons (home-prepared); and, for commercial blends, both with and without puridies amino acid(s) that do or do not include vitamin-antioxidant-mineral mix. The methodology should be widely applicable elsewhere.

Optimization of the Design of Hydrogen Production Systems Based on Product Cost

2020 ◽  
Vol 142 (4) ◽  
Author(s):  
Abdelhamid Mraoui ◽  
Abdallah Khellaf
Keyword(s):  
Hydrogen Production ◽  
Production Systems ◽  
Low Cost ◽  
Minimum Cost ◽  
Total Power ◽  
Photovoltaic Module ◽  
Power Ratio ◽  
The Cost ◽  
Pv Generator ◽  
Practical Constraints

Abstract In this work, the design of a hydrogen production system was optimized for Algiers in Algeria. The system produces hydrogen by electrolysis using a photovoltaic (PV) generator as a source of electricity. All the elements of the system have been modeled to take into account practical constraints. The cost of producing hydrogen has been minimized by varying the total power of the photovoltaic generator. An optimal ratio between the peak power of the PV array and the nominal power of the electrolyzer was determined. Photovoltaic module technology has been varied using a large database of electrical characteristics. It was noted that PV technology does not have a very significant impact on cost. The minimum cost is around 0.44$/N m3, and the power ratio in this case is 1.45. This results in a cost reduction of around 12% compared to a unit ratio. The power ratio and cost are linearly dependent. Only a small number of technologies give a relatively low cost of about 0.35$/N m3. These generators are interesting; however, we assumed an initial cost of $2.00/Wp for all technologies. In addition, it was noted that it is possible to increase hydrogen production by 10% by increasing the power of the photovoltaic generator, the extra cost in this case will only be 0.1%.

scholarly journals Energy Saving and Low-Cost-Oriented Design Processes of Blank’s Dimensions Based on Multi-Objective Optimization Model

Processes ◽  
2019 ◽  
Vol 7 (11) ◽  
pp. 811 ◽  
Author(s):  
Yongmao Xiao ◽  
Qingshan Gong ◽  
Xiaowu Chen
Keyword(s):  
Energy Consumption ◽  
Energy Saving ◽  
Optimization Model ◽  
Low Cost ◽  
Minimum Cost ◽  
Processing Parameters ◽  
Multi Objective Optimization ◽  
Nsga Ii ◽  
Multi Objective ◽  
Set Up

The blank’s dimensions are an important focus of blank design as they largely determine the energy consumption and cost of manufacturing and further processing the blank. To achieve energy saving and low cost during the optimization of blank dimensions design, we established energy consumption and cost objectives in the manufacturing and further processing of blanks by optimizing the parameters. As objectives, we selected the blank’s production and further processing parameters as optimization variables to minimize energy consumption and cost, then set up a multi-objective optimization model. The optimal blank dimension was back calculated using the parameters of the minimum processing energy consumption and minimum cost state, and the model was optimized using the non-dominated genetic algorithm-II (NSGA-II). The effect of designing blank dimension in saving energy and costs is obvious compared with the existing methods.

scholarly journals Optimal Capacity Allocation when Patients encounter Congestion in Primary Healthcare Network

2019 ◽  
Vol 4 (2) ◽  
pp. 400-408
Author(s):  
Kaushal Kumar
Keyword(s):  
Primary Care ◽  
Health Care ◽  
Low Cost ◽  
Minimum Cost ◽  
Capacity Allocation ◽  
Health Care Facilities ◽  
Care Services ◽  
Health Decision ◽  
The Government ◽  
Out Of Pocket Expenses

Universal health care aims at providing low cost or if possible free primary care to everyone. Most countries pursue this goal and it is pertinent for developing countries to make the best use of their limited resources to achieve it. In spite of every effort from the government, unfortunately patients in India spend significant amount of money on travelling and out-of-pocket expenses for availing primary care services even at public funded facilities. We propose an optimization model to help health decision makers in managing existing capacity for alleviation of this problem. The model can be used in the identification of existing health care facilities that need to be upgraded or reduced with a view to improve their utilization at minimum cost. The model recognizes increase in patient out-of-pocket expenses incurred at facilities due to longer waiting time (congestion). Results from numerical experiments are presented to explicate the functioning of the model.

scholarly journals Low-cost Air Purifier Prototype using a Ventilating Fan and Pump against COVID-19 and Haze Pollution

2021 ◽  
Author(s):  
Arnon Jumlongkul
Keyword(s):  
Particulate Matter ◽  
Ultrasonic Wave ◽  
Low Cost ◽  
Reduction Rate ◽  
Minimum Cost ◽  
Water Pump ◽  
Haze Pollution ◽  
Co2 Levels ◽  
Air Cleaners ◽  
Air Purifier

Purpose: This study aimed to focus on the design and development of low-cost DIY air purifiers, using a ventilating fan, air pump, water pump, and an ultrasonic generator, with regard to filtration efficacy and also cost-effectiveness that can be used during the COVID-19 pandemic and haze pollution. Methods: Six types of household air purifiers, incorporating a HEPA filter, a HEPA filter & electrostatic fiber, an air pump, an air pump & ultrasonic wave, a water pump, and a water pump & ultrasonic wave, were fabricated. The amount of particulate matter (PM) and CO2 levels were recorded at 0, 10, 20, 30, and 60 min, then, repeated 3 times. After 10 min of the 3rd experiment of each study, the last measurement of air pollution would be recorded. Results: At 60 min, the HEPA filter & electrostatic fiber showed the best performance regarding reduction of PM and CO2 levels. The highest PM reduction rate had occurred at 30 min using an air pump procedure (99.330 to 100%). The CO2 levels of all experiments had fluctuated at different times. After 10 min of a closed machine, HEPA filter & electrostatic fiber revealed the highest rate of PM elevation, while PM levels of all water-based purifier systems were decreased. A water pump and air pump were the cheapest air cleaners, when taking into account maintenance expenses and electricity charges. Conclusion: An air pump is the optimum method for reducing particulate matter at minimum cost but without the benefit of reduced humidity, while the HEPA filter & electrostatic fiber is the best system to decrease PM levels, but this requires an enclosed structure at the inlet to prevent dust coming back into the room. As filtration efficiency is increased by the use of filters & electrostatic fiber mechanisms, the more expensive the system becomes.

scholarly journals Energetics of Hermit Crabs during Locomotion: The Cost of Carrying a Shell

1986 ◽  
Vol 120 (1) ◽  
pp. 297-308 ◽  
Author(s):  
CLYDE F. HERREID ◽  
ROBERT J. FULL
Keyword(s):  
Fuel Economy ◽  
Low Cost ◽  
Minimum Cost ◽  
Hermit Crabs ◽  
Absolute Difference ◽  
Cost Of Transport ◽  
The Difference ◽  
The Cost ◽  
Response To Exercise ◽  
Leg Position

Oxygen consumption (VOO2) was measured as hermit crabs (Coenobita compressus) walked at controlled velocities on a motor-driven treadmill inside a small respirometer. The crabs displayed an aerobic response to exercise with a rapid increase in VOO2 reaching a steady state in about 5–6 min followed by a rapid recovery. The highest VOO2 was four times the resting rate. VOO2 was directly dependent on the velocity of travel (V): VOO2 = 0.29+1.98V. Metabolic rate was increased significantly in crabs with bilateral leg ablation. The cost of shell carrying was evaluated by comparing VOO2 of crabs with and without their protective snail shells at different velocities; the absolute difference was constant (0.17 ml O2g−1 h−1), suggesting that the cost of shell support was constant per unit of time regardless of speed. The cost of transport dropped dramatically with speed for crabs both with and without snail shells. Crabs carrying shells used twice as much O2 per gram per kilometre as did ‘nude’ crabs walking slowly at 0.02 kmh−1 but the difference decreased to 1.3 times when velocity was increased 10-fold. Hermit crabs did not increase their VOO2 proportionately with load: the VOO2 loaded/unloaded ratio was consistently less than the mass loaded/unloaded ratio. This apparent increase in efficiency may be due to the fact that crabs carrying heavy shells alter their leg position and tend to drag their shell. Crabs with and without shells have the same minimum cost of transport CM, so travel at the highest velocity is theoretically the most economical way to cover a given distance. Appropriately, crabs on the beach average a fast 0.23 km h−1 which produces a low cost of transport only 1.3 times higher than CM. The CM of six-legged hermit crabs is comparable to that of mammals, birds, crabs and insects of similar size and indicates that leg number does not affect fuel economy.

Sign in / Sign up

Export Citation Format

Share Document