scholarly journals Ecological aspect of mobile systems operated in terrain conditions

2012 ◽  
Vol 49 (No. 3) ◽  
pp. 119-123
Author(s):  
A. Janeček ◽  
M. Mikleš
Keyword(s):  
Production System ◽  
Energy Flow ◽  
Forest Ecosystems ◽  
Operating Performance ◽  
Point Of View ◽  
Mobile Systems ◽  
Ecological Aspect ◽  
Optimal Values ◽  
Theoretical Results ◽  
System Point

In this paper is evaluated an optimal constructional and operating performance of the mobil terrain system, that works in forest ecosystems from point of view of volume of processed biomass and total amount of logging transport erosion. A monitored terrain system, working in forestry, is considered as a production system, with its material and energy flow. The determination value, that optimizes the production system, is the operating and constructional performance. In this paper is evaluated the amount erosion in dependence of cutting mass, by means of mathematics and from system point of view. The conditions for the mobile terrain system work, that insure optimal, i.e. minimal value of erosion will be determined. The theoretical results are verified. The optimal values of soil erosion are determined by experimental measurements. The principles of the paper are based on theses of ecological synthesis that determine coupling between dissipative energy of a production system and its ecological cleanliness of work.

scholarly journals Optimisation of a clam bunk skidder from the emission production point of view

2012 ◽  
Vol 58 (No. 4) ◽  
pp. 136-141
Author(s):  
A. Janeček ◽  
R. Adamovský
Keyword(s):  
Mathematical Model ◽  
Production System ◽  
Operating Performance ◽  
Point Of View ◽  
Optimal Rate ◽  
Simple Mathematical Model ◽  
Operation Performance ◽  
The Mathematical Model

This article presents a proposal of a simple mathematical model for minimisation of the production of extraneous substances as a function of the rate of operation performance of a production system. The model is then verified by operation tests of the Terri 2040 clam bunk skidder and by determining the system&rsquo;s optimal rate of performance from the point of view of production of SO<sub>2</sub>, HC and NO<sub>x </sub>emissions. The operation tests conducted to verify the mathematical model have confirmed that conditions can be determined for the production system at which it produces minimum emissions. Min. values of SO<sub>2</sub>, and HC were achieved at approximately the same rate of performance of the clam bunk skidder. Minimum values of NO<sub>x </sub>were achieved at significantly higher rate of performance of the equipment. At the calculated optimal rate of operating performance of the Terri 2040 clam bunk skidder, the values of the produced emissions were determined per m<sup>3</sup> of timber: SO<sub>2</sub> = 1.00035 g/m<sup>3</sup>, HC = 7.796 g/m<sup>3</sup> and NO<sub>x</sub> = 0.277 g/m<sup>3</sup>.

scholarly journals Fatty acids in intramuscular fat of Ile de France lambs in two different production systems

2018 ◽  
Vol 61 (4) ◽  
pp. 395-403
Author(s):  
Milan Margetín ◽  
Marta Oravcová ◽  
Jana Margetínová ◽  
Róbert Kubinec
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Linoleic Acid ◽  
Production System ◽  
Production Systems ◽  
Intramuscular Fat ◽  
Point Of View ◽  
Longissimus Dorsi ◽  
Fa Composition ◽  
Long Chain

Abstract. The fatty acid (FA) composition in the intramuscular fat (IMF) of the musculus longissimus dorsi (MLD) of Ile de France purebred lambs in two different production systems in Slovakia was evaluated using gas chromatography. In the first production system, lambs and ewes were assigned to pasture without access to concentrates (P). In the second system, lambs and ewes were confined indoors with hay/silage and access to concentrates (S). An analysis of variance with the following factors was employed: production system, sex, and production system–sex interactions. The proportions of arachidonic, eicosapentaeonic, docosapentaeonic, and docosahexaenoic FAs, i.e. long-chain polyunsaturated FA (PUFA), were significantly higher in P lambs (1.83, 0.82, 0.92, 0.29 g 100 g−1 FAME, respectively) than in S lambs (0.45, 0.14, 0.30, 0.09 g 100 g−1 FAME, respectively). The proportions of conjugated linoleic acid (CLA), n-6 PUFA, n-3 PUFA, and essential FA (linoleic and α-linolenic) were also significantly higher in P lambs (2.10, 8.50, 4.55, and 8.80 g 100 g−1 FAME, respectively) than in S lambs (0.65, 3.27, 1.50, and 3.64 g 100 g−1 FAME, respectively). The proportions of palmitic acid and myristic acid as important individual saturated FAs (SFA) were significantly higher in S lambs (28.51 and 8.30 g 100 g−1 FAME, respectively) than in P lambs (21.80 and 5.63 g 100 g−1 FAME, respectively). The proportion of all SFAs was also significantly higher in S lambs (57.87 g 100 g−1 FAME) than in P lambs (48.70 g 100 g−1 FAME). From a nutrition and human health point of view (i.e. higher proportions of PUFA, CLA, and essential FAs and lower proportions of SFAs), meat from P lambs was found to be more favourable and would be more highly recommended for consumption.

Analytical Investigation of the Effects of Induction Motor Transients on Compressor Drive Shafts

2011 ◽  
Author(s):  
Anand Srinivasan
Keyword(s):  
Mechanical System ◽  
Induction Motor ◽  
Analytical Investigation ◽  
Point Of View ◽  
Electrical Parameters ◽  
Short Circuits ◽  
Torque Values ◽  
Driving Torque ◽  
Electrical Supply ◽  
System Point

Centrifugal compressors driven by induction motors are most common in the turbomachinery industry. When sudden transients occur in the driver due to upsets in electrical supply to the motor, the air-gap torque generated by the motor undergoes a transient spike. This in turn gets transmitted through the coupling to the drive-shaft of the driven equipment, causing momentary high spikes in vibration that are torsional in nature, and can sometimes result in shaft torques that can create catastrophic damage to driven equipment components. In order to analytically predict these peak torques that can occur during transients, a complete drive-train torsional model needs to be created for the mechanical system, and the driving torque values need to be derived from the motor electrical system of equations. Various line faults are possible with induction motor driven equipment. A generalized analytical procedure based on motor electrical parameters to predict the peak shaft torques of compressor drive shafts is investigated in this paper. The effects of shaft transients due to 3-phase short circuits and reclosures are analyzed. The simulation has been performed for an industrial compressor train, and has been presented from a mechanical system point of view, rather than electrical. Comparisons and inferences are also made based on the simulation results.

scholarly journals A Competitive Memory Paradigm for Multimodal Optimization Driven by Clustering and Chaos

Mathematics ◽  
2020 ◽  
Vol 8 (6) ◽  
pp. 934
Author(s):  
Jorge Gálvez ◽  
Erik Cuevas ◽  
Krishna Gopal Dhal
Keyword(s):  
Optimization Problems ◽  
Optimization Methods ◽  
Global Optimum ◽  
Point Of View ◽  
The Other ◽  
Memory Mechanism ◽  
Dominant Individual ◽  
Complex Optimization ◽  
Optimal Values ◽  
Evolutionary Operators

Evolutionary Computation Methods (ECMs) are proposed as stochastic search methods to solve complex optimization problems where classical optimization methods are not suitable. Most of the proposed ECMs aim to find the global optimum for a given function. However, from a practical point of view, in engineering, finding the global optimum may not always be useful, since it may represent solutions that are not physically, mechanically or even structurally realizable. Commonly, the evolutionary operators of ECMs are not designed to efficiently register multiple optima by executing them a single run. Under such circumstances, there is a need to incorporate certain mechanisms to allow ECMs to maintain and register multiple optima at each generation executed in a single run. On the other hand, the concept of dominance found in animal behavior indicates the level of social interaction among two animals in terms of aggressiveness. Such aggressiveness keeps two or more individuals as distant as possible from one another, where the most dominant individual prevails as the other withdraws. In this paper, the concept of dominance is computationally abstracted in terms of a data structure called “competitive memory” to incorporate multimodal capabilities into the evolutionary operators of the recently proposed Cluster-Chaotic-Optimization (CCO). Under CCO, the competitive memory is implemented as a memory mechanism to efficiently register and maintain all possible optimal values within a single execution of the algorithm. The performance of the proposed method is numerically compared against several multimodal schemes over a set of benchmark functions. The experimental study suggests that the proposed approach outperforms its competitors in terms of robustness, quality, and precision.

Analysis and Optimization of Material Flow and Energy Flow in the Coking-Steel Co-Production System

2012 ◽  
Vol 524-527 ◽  
pp. 1980-1988
Author(s):  
Hong Fu Li ◽  
Shuo Yun Liu ◽  
Li Hua Zhao ◽  
Hao Bai ◽  
Da Qiang Cang ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Production System ◽  
Material Flow ◽  
Energy Flow ◽  
Waste Heat ◽  
Coal Resources ◽  
Coal Gas ◽  
Efficiency Increase ◽  
Novel Model ◽  
Coking Industry

In this paper, material and energy flow in the coking process were analyzed and thus the possibility of resource and energy efficiency increase was pointed out. Considering the unreasonable structure of coking industry currently, a novel model of coking-steel co-production system was built and its advantages were analyzed in the respects of the use of coal gas, waste heat and coal resources. The results show that the coking-steel co-production system has the more obvious advantages than the traditional coking process.

On the Prediction of Turbulent Jet Noise Using Traditional Aeroacoustic Methods

2005 ◽  
Vol 4 (3) ◽  
pp. 289-323 ◽  
Author(s):  
K.M. Khritov ◽  
V.Ye. Kozlov ◽  
S.Yu. Krasheninnikov ◽  
A.B. Lebedev ◽  
D.A. Lyubimov ◽  
...  
Keyword(s):  
Single Point ◽  
Jet Noise ◽  
Point Of View ◽  
Turbulent Jet ◽  
Prediction Methods ◽  
Noise Prediction ◽  
Classical Literature ◽  
Boeing Company ◽  
The Many ◽  
Theoretical Results

Several experimental, computational and theoretical results devoted to turbulence jet noise are described. All these results were obtained at CIAM in collaboration with the Boeing Company. The selected topics are combined and described from a single point of view. In spite of the many publications in the classical literature devoted to jet noise, many jet noise problems are not completely solved, and most current jet noise prediction methods are still highly empirical and rely heavily on an existing experimental data base. At the same time, many of the available experimental results are not fully reliable and some are even contradictory. The goal of this paper is, therefore, to explore and discuss some of the possibilities and limitations of classical aeroacoustics methods.

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