Narrow-Band k-Distribution Database for Atomic Radiation in Hypersonic Nonequilibrium Flows

Author(s):  
Ankit Bansal ◽  
Michael F. Modest ◽  
Deborah Levin

Full-spectrum k-distribution (FSK) and multi-group FSK approaches make it possible to evaluate radiative fluxes at a fraction of the cost needed for line-by-line calculations. However, the required k-distributions need to be assembled from accurate absorption coefficient data for each flow condition, which is computationally expensive. An accurate and compact narrow-band k-distribution database has been developed for the most important species encountered in hypersonic nonequilibrium flow. The database allows users to calculate desired full-spectrum k-distributions through look-up and interpolation. Strategies for k-distribution data generation are outlined. The accuracy of the database is tested by comparing narrow-band mean absorption coefficients and narrow-band emissivities with those obtained from line-by-line calculations. Application of the database to construct full-spectrum k-distributions accurately and efficiently is discussed, and results from a number of heat transfer calculations and cpu-time studies are presented.

2011 ◽  
Vol 133 (12) ◽  
Author(s):  
Ankit Bansal ◽  
Michael Modest

An accurate and compact part-spectrum k-distribution database has been developed for the two most important radiating species N and O encountered in hypersonic nonequilibrium flows. The database allows users to calculate the desired full-spectrum k-distributions through look-up and interpolation, providing an efficient means to perform radiative transfer calculations. A detailed methodology of the k-distribution data generation is presented. An optimized Gauss quadrature scheme is implemented for reducing the size of the database. The accuracy of the database is determined by comparing part-spectrum emissivities with those obtained from line-by-line calculations. The application of the database to construct full-spectrum k-distributions at arbitrary gas states is discussed. Heat transfer results for the stagnation line of the Stardust vehicle are discussed and CPU-time studies are presented, demonstrating the accuracy and efficiency of the k-distribution database.


Author(s):  
A. A. Golikov ◽  
◽  
J. A. Oleynik

Bridges located on maritime and inland waterways are defenseless objects of infrastructure. One of their main features is the restriction of navigation channels, both vertically and horizontally, while navigation conditions may often be challenged by unpredictable currents and whirlpools. A great threat to people and vehicles on or near the structure occurred in case of a collision with ships and the destruction of bridges. Also, the consequences of such accidents are considerable financial expenses, where the cost of the bridge is usually much more than the cost of the vessel itself. The article addresses the issue of types, factors, causes and consequences of ship-bridge collision accidents. In spite of the modern level of development in the maritime industry such accidents occur annually, thus this problem is considered to be relevant nowadays. It is necessary to take measures to increase the safety of navigation in appropriate zones. The article presents the procedure for assessing the level of safety and the stages of identifying risks by determining the probability of a collision with bridge spans, supports and other structures, also identifying the most defenseless places, as well as the possible consequences of such damage (ship, city, environment). In addition, the paper considered the methods of protecting the bridge from collision and methods for reducing navigational risk. The results of the research are the development of the recommendations for avoiding possible dangers, mitigation of consequences, and reducing risks of vessel-bridge collision. It is proposed to form an “intellectual” zone in the navigable water area under the bridge to minimize the risks and consequences of an emergency. As a basic concept, it is recommended to use foreign and domestic experience in implementing the e-navigation strategy in the coastal zone and in the operational VTS areas. The article describes the implementation of modern marine technologies, such as virtual navigation aids and technologies of additional reality, which will significantly improve monitoring of the environment. Therefore, this introduction will reduce the risk of an emergency. Ensuring the full spectrum of available methods is necessary to determine risk and protect bridges from accidents. Such an approach shall allow not only to assess the risk of ship-bridge collision, but also to introduce additional active control elements during navigation in dangerous zones.


2021 ◽  
Author(s):  
Schuyler D. Smith ◽  
Jin Choi ◽  
Nicole Ricker ◽  
Fan Yang ◽  
Shannon Hinsa-Leasure ◽  
...  

Effective monitoring of antibiotic resistance genes and their dissemination in environmental ecosystems has been hindered by the cost and efficiency of methods available for the task. We developed a method entitled the Diversity of Antibiotic Resistance genes and Transfer Elements-Quantitative Monitoring (DARTE-QM), a system implementing high-throughput sequencing to simultaneously sequence thousands of antibiotic resistant genes representing a full-spectrum of antibiotic resistance classes commonly seen in environmental systems. In this study, we demonstrated DARTE-QM by screening 662 antibiotic resistance genes within environmental samples originated from manure, soil, and animal feces, in addition to a mock-community used as a control to test performance. DARTE-QM offers a new approach to studying antibiotic resistance in environmental microbiomes, showing advantages in efficiency and the ability to scale for many samples. This method provides a means of data acquisition that will alleviate the obstacles that many researchers in this area currently face.


2014 ◽  
Vol 1008-1009 ◽  
pp. 839-845
Author(s):  
Yue Zhou ◽  
Qiang Wang ◽  
Hai Yang Hu

The k-distribution method applied in narrow band and wide band is extended to the full spectrum based on spectroscopic datebase HITEMP, educing the full-spectrum k-distribution model. Absorption coefficents in this model are reordered into a smooth,monotonically increasing function such that the intensity calculations are performed only once for each absorption coefficent value and the resulting computations are immensely more efficent.Accuracy of this model is examined for cases ranging from homogeneous one-dimensional carbon dioxide to inhomogeneous ones with simultaneous variations in temperature. Comparision with line-by-line calculations (LBL) and narrow-band k-distribution (NBK) method as well as wide-band k-distribution (WBK) method shows that the full-spectrum k-distribution model is exact for homogeneous media, although the errors are greater than the other two models. After dividing the absorption coefficients into several groups according to their temperature dependence, the full-spectrum k-distribution model achieves line-by-line accuracy for gases inhomogeneous in temperature, accompanied by lower computational expense as compared to NBK model or WBK model. It is worth noting that a new grouping scheme is provided in this paper.


Electronics ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1753
Author(s):  
Yangan Zhang ◽  
Guichen Chen ◽  
Hang Du ◽  
Xueguang Yuan ◽  
Michel Kadoch ◽  
...  

Telemedicine over Internet of Things (IoT) generates an unprecedented amount of data, which further requires transmission, analysis, and storage. Deploying cloud computing to handle data of this magnitude will introduce unacceptable data analysis latency and high storage costs. Thus, mobile edge computing (MEC) deployed between the cloud and users, which is close to the nodes of data generation, can tackle these problems in 5G scenarios with the help of artificial intelligence. This paper proposes a telemedicine system based on MEC and artificial intelligence for remote health monitoring and automatic disease diagnosis. The integration of different technologies such as computers, medicine, and telecommunications will significantly improve the efficiency of patient treatment and reduce the cost of health care.


2015 ◽  
Vol 20 (2) ◽  
Author(s):  
Rodrigo Yudi Fujimoto ◽  
Rudã Fernandes Brandão Santos ◽  
Claucia Aparecida Honorato ◽  
Henrique Malta Dias ◽  
Fabrício Menezes Ramos ◽  
...  

Angelfish (Pterophyllum scalare) is a very important species in Brazil’s domestic market, enjoying feeding managements that differ from fish breeders to aquarists, so the cost of feed and labor become relevant items when cultivating the species. Thus, the objective of this work was to assess feeding frequency and feed deprivation based on growth performance, parasite infestation and cost-benefit in farming the species. The experiment was conducted in a completely randomized design in a 3x2 factorial scheme with 3 daily feeding levels, 4 meals, 2 meals and 1 meal; with and without feed deprivation and two repetitions. Feed deprivation consisted of offering feed 5 days a week only. Considering the performance, we observed that feeding once a day is the management of choice when the objective is maintaining fish weight. Feeding twice a day without deprivation and four times a day with or without feed deprivation resulted in higher growth performance than feeding once a day. Monogenean and nematode loads were not influenced by feeding management. The cost-benefit analysis enabled us to observe that the treatment with the best benefit was the one involving two feedings a day with no deprivation. Thus, considering the parameters mentioned above, we concluded that the treatment consisting of two daily feedings with no feed deprivation is the most adequate for farming this specie.


2009 ◽  
Vol 132 (2) ◽  
Author(s):  
Gopalendu Pal ◽  
Michael F. Modest

The full-spectrum k-distribution (FSK) approach has become a promising method for radiative heat transfer calculations in strongly nongray participating media, due to its ability to achieve high accuracy at a tiny fraction of the line-by-line (LBL) computational cost. However, inhomogeneities in temperature, total pressure, and component mole fractions severely challenge the accuracy of the FSK approach. The objective of this paper is to develop a narrow band-based hybrid FSK model that is accurate for radiation calculations in combustion systems containing both molecular gases and nongray particles such as soot with strong temperature and mole fraction inhomogeneities. This method combines the advantages of the multigroup FSK method for temperature inhomogeneities in a single species, and the modified multiscale FSK method for concentration inhomogeneities in gas-soot mixtures. In this new method, each species is considered as one scale; the absorption coefficients within each narrow band of every gas scale are divided into M exclusive spectral groups, depending on their temperature dependence. Accurate and compact narrow band multigroup databases are constructed for combustion gases such as CO2 and H2O. Sample calculations are performed for a 1D medium and also for a 2D axisymmetric combustion flame. The narrow band-based hybrid method is observed to accurately predict heat transfer from extremely inhomogeneous gas-soot mixtures with/without wall emission, yielding close-to-LBL accuracy.


2003 ◽  
Vol 7 (4) ◽  
pp. 207-228 ◽  
Author(s):  
Hrvoje Podnar ◽  
Jadranka Skorin-Kapov

We present a genetic algorithm for heuristically solving a cost minimization problem applied to communication networks with threshold based discounting. The network model assumes that every two nodes can communicate and offers incentives to combine flow from different sources. Namely, there is a prescribed threshold on every link, and if the total flow on a link is greater than the threshold, the cost of this flow is discounted by a factor α. A heuristic algorithm based on genetic strategy is developed and applied to a benchmark set of problems. The results are compared with former branch and bound results using the CPLEX® solver. For larger data instances we were able to obtain improved solutions using less CPU time, confirming the effectiveness of our heuristic approach.


Mining is the backbone of any industrial activity. Mother nature has bestowed India with good deposits of coal, iron ore, limestone, bauxite, manganese and chromite ores. Indian economy is one of the fastest growing economies in the world today. To fulfill 8-10 % growth target, Indian mining industry has to increase its share from 2.4 % to 6 %. (1)Such voluminous increments can be met only by employing big size heavy earth moving machines (HEMM)(2). Dumpers are the common choice in all types of mines for material movement. There are 4200 dumpers of various sizes being used in the different mines in India. The cost of dumpers varies from Rs 1.0 crore for 35 tons to Rs 24 crore for 240 tons version.( 3) The availability and utilization percentage of dumpers is low as compared to other HEMM. Hence there is a need for continuous monitoring of operational and machine parameters. Presently, only in large mines GPS based systems are being used to monitor such parameters. In small and medium mines monitoring is manual in nature. Manual method of data generation has its own limitations with respect to time and reliability. GPS based systems are not only costly but also requires qualified manpower to operate and maintain it. This calls for indigenous development of economical management information system (MIS) which could produce temper proof on line data. This research paper discusses one such management information system developed by the authors which is economical, easy to maintain and which produces reliable data


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