scholarly journals The relationship between culling rate, herd structure and production efficiency in a pig nucleus herd

2009 ◽  
Vol 54 (No. 8) ◽  
pp. 365-375 ◽  
Author(s):  
L. Houška
Keyword(s):  
Computer Simulation ◽  
Age Structure ◽  
Production Efficiency ◽  
Constant Size ◽  
Herd Structure ◽  
The Relationship

Computer simulation of sow culling was run in a nucleus herd. The specified constant culling rate from 15 to 21% was simulated for all parities. The resultant different age structure of a herd was studied from the aspect of piglet production and other production indicators. With increasing culling rate the percentage of mated gilts was increased in order to maintain the constant size of the sow herd. With 15% simulated culling, which required 17.09% of mated gilts, the percentage of sows at parity 1 and 2 and the percentage of sows at parities 3–5 were balanced (31.62% and 31.77%, respectively). Annual herd replacement was 37.62%. After five parities only a little more than a half (55.63%) of the total number of sows in the herd was removed. Similar results were obtained with 16% culling, which also made it possible to maintain the recommended herd structure. With higher culling rate parities 1 and 2 became dominant in the herd. With 21% culling and 19.84% of mated gilts the percentage of sows at parities 1 and 2 was 35.52% while it was only 29.90% at parities 3–5. Annual herd replacement amounted to 43.67%, and almost 70% of sows were removed after five parities in this case. With increasing culling rate the average age of sows removed from a herd decreased (1 158.1–1 021.2 days), the number of barren days in a herd per year increased (6 174–6 680 days) and the number of piglets weaned per sow per year decreased (19.54–18.92 piglets). At the same time, there was a decrease in total costs (64 789–63 519 Kč), returns (79 816–77 327 Kč) and profit (15 026–13 808 Kč) in the herd, as recalculated per sow per year, and profitability also decreased.

scholarly journals Environmental Production Efficiency in the European Union Countries as a Tool for the Implementation of Goal 7 of the 2030 Agenda

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4593
Author(s):  
Katarzyna Cheba ◽  
Iwona Bąk
Keyword(s):  
European Union ◽  
Production Efficiency ◽  
Energy Use ◽  
The European Union ◽  
2030 Agenda ◽  
European Union Countries ◽  
Taxonomic Methods ◽  
Development Levels ◽  
The Relationship ◽  
The Eu

The main purpose of the paper is to present a proposal to measure the relationships between Goal 7 of the 2030 Agenda for Sustainable Development and one of the areas considered in the green growth concept: environmental production efficiency. Both of these areas illustrate the relationship between the natural environment and the economy, emphasizing transformations in the field of energy use. Selected taxonomic methods, TOPSIS, and multicriteria taxonomy, were applied to study the relationships between the two areas. The results of the EU countries classification showed a variety of countries’ development pathways within a single economic community. Despite continued attempts to equalize the development levels between European Union countries in many strategic areas, they remain highly diversified. That is also true for the areas analyzed in the paper, which is a disturbing situation, indicating that both strategies might not correlate in all respects. Further research into the relationships linking the remaining dimensions of both strategies is required.

Computer Simulation of the Responses of Human Motoneurons to Composite 1A EPSPS: Effects of Background Firing Rate

1997 ◽  
Vol 77 (1) ◽  
pp. 405-420 ◽  
Author(s):  
Kelvin E. Jones ◽  
Parveen Bawa
Keyword(s):  
Computer Simulation ◽  
Firing Rate ◽  
Time Course ◽  
Current Model ◽  
Response Probability ◽  
Muscle Spindles ◽  
Excitatory Postsynaptic Potential ◽  
Biophysical Properties ◽  
Rhythmic Firing ◽  
The Relationship

Jones, Kelvin E. and Parveen Bawa. Computer simulation of the responses of human motoneurons to composite 1A EPSPS: effects of background firing rate. J. Neurophysiol. 77: 405–420, 1997. Two compartmental models of spinal alpha motoneurons were constructed to explore the relationship between background firing rate and response to an excitatory input. The results of these simulations were compared with previous results obtained from human motoneurons and discussed in relation to the current model for repetitively firing human motoneurons. The morphologies and cable parameters of the models were based on two type-identified cat motoneurons previously reported in the literature. Each model included five voltage-dependent channels that were modeled using Hodgkin-Huxley formalism. These included fast Na+ and K+ channels in the initial segment and fast Na+ and K+ channels as well as a slow K+ channel in the soma compartment. The density and rate factors for the slow K+ channel were varied until the models could reproduce single spike AHP parameters for type-identified motoneurons in the cat. Excitatory synaptic conductances were distributed along the equivalent dendrites with the same density described for la synapses from muscle spindles to type-identified cat motoneurons. Simultaneous activation of all synapses on the dendrite resulted in a large compound excitatory postsynaptic potential (EPSP). Brief depolarizing pulses injected into a compartment of the equivalent dendrite resulted in pulse potentials (PPs), which resembled the compound EPSPs. The effects of compound EPSPs and PPs on firing probability of the two motoneuron models were examined during rhythmic firing. Peristimulus time histograms, constructed between the stimulus and the spikes of the model motoneuron, showed excitatory peaks whose integrated time course approximated the time course of the underlying EPSP or PP as has been shown in cat motoneurons. The excitatory peaks were quantified in terms of response probability, and the relationship between background firing rate and response probability was explored. As in real human motoneurons, the models exhibited an inverse relationship between response probability and background firing rate. The biophysical properties responsible for the relationship between response probability and firing rate included the shapes of the membrane voltage trajectories between spikes and nonlinear changes in PP amplitude during the interspike interval at different firing rates. The results from these simulations suggest that the relationship between response probability and background firing rate is an intrinsic feature of motoneurons. The similarity of the results from the models, which were based on the properties of cat motoneurons, and those from human motoneurons suggests that the biophysical properties governing rhythmic firing in human motoneurons are similar to those of the cat.

scholarly journals Using Computer Simulation Method to Improve Throughput of Production Systems by Buffers and Workers Allocation

2015 ◽  
Vol 6 (4) ◽  
pp. 60-69 ◽  
Author(s):  
Sławomir Kłos ◽  
Peter Trebuna
Keyword(s):  
Computer Simulation ◽  
Production System ◽  
Production Systems ◽  
Simulation Method ◽  
System Throughput ◽  
Buffer Allocation ◽  
Simulation Experiments ◽  
Buffer Capacities ◽  
The Relationship ◽  
Support Decision Making

Abstract This paper proposes the application of computer simulation methods to support decision making regarding intermediate buffer allocations in a series-parallel production line. The simulation model of the production system is based on a real example of a manufacturing company working in the automotive industry. Simulation experiments were conducted for different allocations of buffer capacities and different numbers of employees. The production system consists of three technological operations with intermediate buffers between each operation. The technological operations are carried out using machines and every machine can be operated by one worker. Multi-work in the production system is available (one operator operates several machines). On the basis of the simulation experiments, the relationship between system throughput, buffer allocation and the number of employees is analyzed. Increasing the buffer capacity results in an increase in the average product lifespan. Therefore, in the article a new index is proposed that includes the throughput of the manufacturing system and product life span. Simulation experiments were performed for different configurations of technological operations.

scholarly journals Weaving the Common Threads of Simulation and Formation studies in Archaeology

2017 ◽  
Author(s):  
Benjamin Davies
Keyword(s):  
Computer Simulation ◽  
Human Activity ◽  
Computational Models ◽  
Experimental Studies ◽  
Surface Erosion ◽  
Archaeological Record ◽  
The Common ◽  
The Relationship ◽  
Material Record

Computer simulation is a tool increasingly used by archaeologists to build theories about past human activity; however, simulation has had a limited role theorising about the relationship between past behaviours and the formation of observed patterning in the material record. This paper visits the argument for using simulation as a means of addressing the gap that exists between archaeological interpretations of past behaviours and their physical residues. It is argued that simulation is used for much the same reason that archaeologists use ethnographic or experimental studies, and that computational models can help to address some of the practical limitations of these approaches to record formation. A case study from arid Australia, examining the effects of episodic surface erosion on the visibility of the record, shows how simple, generative simulations, grounded in formational logic, can be used to compare different explanatory mechanisms and suggest tests of the archaeological record itself.

scholarly journals The Relationship between China’s Financial Industry Performance and Energy Elimination

2019 ◽  
Vol 81 ◽  
pp. 01023
Author(s):  
Jun-Qi Wu ◽  
Li-Chen Chou
Keyword(s):  
Energy Consumption ◽  
Production Efficiency ◽  
Mainland China ◽  
Financial Industry ◽  
Empirical Results ◽  
Annual Basis ◽  
Average Production ◽  
Industry Performance ◽  
Research Objects ◽  
The Relationship

Taking the provinces, autonomous regions and cities in mainland China as the research objects, this paper collects and collates the data of production, input and energy consumption of the financial industry from 2009 to 2014, and analyzes the production efficiency of each region. The empirical results show that the production efficiency of all prefecture-level cities is 0.782. If analysed on region basis, the average production efficiency of prefecture-level cities is the highest in the eastern provinces, followed by the central provinces and the lowest in the western provinces. If analysed on annual basis, the distribution of production efficiency shows a trend of decline during 2009-2010 and increase after 2012.

Equations for postnatal chemical composition of the fat-free empty body of sheep and cattle

1983 ◽  
Vol 100 (3) ◽  
pp. 693-699 ◽  
Author(s):  
T. W. Searle ◽  
D. A. Griffiths
Keyword(s):  
Computer Simulation ◽  
Weight Loss ◽  
Regression Analysis ◽  
Compensatory Growth ◽  
Simulation Models ◽  
Published Data ◽  
Simple Description ◽  
Positive Growth ◽  
Computer Simulation Models ◽  
The Relationship

SUMMARYRegression analysis was used to examine the relationship between the weight of water, protein and ash (kg) and fat-free empty body (FFEB) weight (kg) in data from six published and one unpublished experiment conducted in this laboratory. The analysis involved 201 sheep divided into 12 groups which were either in positive growth, weight stasis, weight loss or compensatory growth prior to slaughter. Each of the relationships between water, protein or ash and FFEB was linear and could be expressed by a common slope. Small (though statistically significant) differences in intercept were found between treatments. The following overall equations provide a simple description of the data:water (kg) = 0·721 FFEB + 0·37, R.S.D. 0·18,protein (kg) = 0·215 FFEB - 0·22, R.S.D. 0·16,ash (kg) = 0·055 FFEB - 0·07, R.S.D. 0·09.Published data for cattle were also examined and corresponding equations are:water (kg) = 0·701 FFEB + 3·59, R.S.D. 2·6,protein (kg) = 0·234 FFEB - 2·00, R.S.D. 2·3,ash (kg) = 0·060 FFEB - 0·71, R.S.D. 1·8.It is suggested that these equations could be used in computer simulation models of growth to calculate FFEB gain (or loss) from nitrogen balance.

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