Tópicos Sugeridos dentro de su búsqueda.
Tópicos Sugeridos dentro de su búsqueda.
1
artículo
Publicado 2015
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The objectives of this study were to describe the growth of young llamas by the application of four non-linear functions (Gompertz, Logistic, Von Bertalanffy and Brody), evaluate the importance of fixed (environmental) effects (sex, type of llama, month and year of birth) on growth curve parameters and finally estimate the genetic parameters for growth curve parameters (A: asymptotic body weight and k: specific growth rate). A total of 35,691 monthly body weight records from birth up to 16 months of age from 2675 young llamas, collected from 1998 to 2008 in the Quimsachata Experimental Station of the Instituto Nacional de Innovación Agraria (INIA) in Peru were used. Growth curve parameters were estimated by non-linear procedures while genetic parameters were estimated by application of a bivariate animal model and the restricted maximum likelihood (REML) method. All non-linear functions...
2
artículo
Publicado 2023
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We consider the adaptive finite element discretization of parameter estimation problems for nonlinear elliptic partial differential equations. The idea is to use a gradient method on the finite-dimensional parameter space for the minimization of the least-squares residual. Since the gradient involves solution of partial differential equations, it is not accesable, and is replaced by an approximation obtained by finite elements. This results into a perturbed gradient method. We use an (a posteriori) error estimator to control the accuracy of the gradient approximation and propose an algorithm, which links the estimator to the progress of the iteration. We show convergence of the algorithm under typical structural assumptions.
3
artículo
Publicado 2023
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We show the structure of the parameter space for a family of rational maps containing Blaschke products. Through numerical simulations using the orbit of a single critical point, we reveal the existence of infinitely many Mandelbrot-like sets along the unit circle, as well as eight-like structures in other regions of parameter space. We pose some open questions related to the parameter space of these functions.
4
artículo
In the current era; of the cult to the body, to the health, to the image and to the wellbeing; one must have a vision of the patient in a more holistic way; in which, it is not only essential to consider the health and function of the teeth; but seek to achieve the greatest aesthetics of the smile considering the needs and expectations of patients. Therefore, in the present review we aim to know the perception of the aesthetic parameters that are most evaluated in the smile analysis; both by professionals, as by patients.
5
tesis de grado
Publicado 2021
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La región de Arequipa posee la mayor extensión del litoral peruano en el mar Pacífico, también posee recursos de agua dulce compuestos por ríos y lagunas desde la costa hasta la sierra de los Andes. El vehículo ALBA es una embarcación de superficie autónoma de bajo costo con arquitectura de código abierto que se está desarrollando para respaldar las tareas de monitoreo del agua en la región. Este artículo trata el problema de identificación no lineal para una nave autónoma de superficie y se utiliza el método de estimación de máxima verosimilitud para estimar sus parámetros. El modelo paramétrico no lineal se considera con datos experimentales y simulados. Los resultados muestran buenos valores de ajuste cuando se estiman dos, tres y un máximo de cuatro parámetros
6
objeto de conferencia
Publicado 2016
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Se propuso QIEA-R (Quantum Inspired Evolutionary Algorithm with Real Codification) para resolver problemas numéricos obteniendo mejores resultados en comparación con los algoritmos tradicionales de EAs, DE y PSO. Se inspira en el concepto de superposición cuántica para reducir el número de evaluaciones. QIEA-R tiene dos pasos importantes: inicialización de la población cuántica y actualización de la población cuántica. Este trabajo analiza estos dos pasos y parámetros relacionados: Tamaño de la población clásica, número de iteraciones, sobre algunas funciones de referencia utilizando mediciones estadísticas para evaluar su importancia y efecto en la calidad de convergencia. Los resultados muestran la importancia del tamaño de la población cuántica y la frecuencia de actualización.
7
artículo
Publicado 2009
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The age at first service (EPS), age at first calving (EPP), calving – first service interval (IPPS), calving – conception interval (IPC), inter-calving interval (IEP), number of services per conception (NSC), conception rate at first service (TCPS) and overall conception rate (TCG) were determined from historical data of 559 dairy cows from 4 intensive milk dairy farms in the Lima region. Variables under analysis were farm, calving season (summer: December–March; winter: April–August; spring: September–November) and parity (primmiparous; multiparous). EPS was 17.5 ± 0.1 months (n = 559), EPP was 27.2 ± 0.2 months (n = 455), IPPS was 109.2 ± 1.5 days (n = 1233), IPC was 181.1 ± 3.4 days (n = 1035), IEP was 15.2 ± 0.1 months (n = 775), NSC was 2.41, TCPS was 46.1% (66.9 and 36.5% en heifers and cows, respectively) and TCG was 41.5%. IPPS of cows that calved in winter was sta...
8
artículo
Publicado 2021
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The purpose of this study was to develop and test a methodological approach to optimizing the business processes of the leather industry company of the Republic of Iraq on the basis of a series of sequential steps, including both assessing the individual parameters of the differentiation of the competitive strategy and identifying problem areas for further setting up business processes. The results of the study are expressed in the form of developing an author's algorithm for identifying competitiveness parameters in accordance with the type of competitive strategy, as well as in the form of developing a matrix for determining a competitive strategy. By summarizing the scientific research, the authors presented for scientific consideration the main parameters of differentiation of the business model of leather products, as well as the analytical scheme of cost analysis in relation to the...
9
artículo
Publicado 2019
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The objective of this study was to determine the hematological values of Brycon amazonicus broodstock under culture in Iquitos, Peru. Blood samples were taken from 12 specimens (1.62 ± 0.45 kg and 51.38 ± 2.93 cm) maintained in earthen ponds and fed twice a day with a commercial diet with 22% crude protein. The fish were collected with a net and anesthetized with eugenol. Blood extraction was performed with disposable syringes containing EDTA (10%). The values obtained from the erythrocytic series were: hematocrit 53.3 ± 4.8%; hemoglobin 20.1 ± 3.2 g/dl; erythrocytes 2.8 ± 0.5 x106/μl; VCM 194.4 ± 54.4 fl; CHCM 37.7 ± 4.8 g/dl; HCM 72.6 ± 17.7 pg. The number of leukocytes was 8.1 ± 6.0 x103/μl. In the differential count of leukocytes, the lymphocytes and monocytes had greater proportion in comparison with neutrophils, eosinophils and basophils. The total serum protein was 3.7 ...
10
artículo
Publicado 2013
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The present research was conducted in order to determine the parameters of production and conservation of adult bovine rennet. Dry abomasum was chunked and proceeded to the extraction of the enzyme with hydrochloric acid 3 mM, pH 2,5. Was activated enzyme solution and filtered to yield the liquid rennet with 1:607,59 force (± 1,58) Soxhlet Units. Liquid rennet was filled in low density polyethylene milky white bottles and stored for one month at 4°C, -7°C and -198°C, to later evaluation. The strength of liquid rennet in storage at 4°C did not yield good results, because loss of the 38,47% of force. Stored liquid rennet to temperature of -7°C, generated a power loss of 30,94%, being the basal strength of 1:419,58 (± 1,47) in U.S. (Units Soxhlet). Storage of liquid rennet to -198°C (liquid nitrogen), was appropriate to preserve with power loss.
11
artículo
Publicado 2021
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The purpose of this study was to develop and test a methodological approach to optimizing the business processes of the leather industry company of the Republic of Iraq on the basis of a series of sequential steps, including both assessing the individual parameters of the differentiation of the competitive strategy and identifying problem areas for further setting up business processes. The results of the study are expressed in the form of developing an author's algorithm for identifying competitiveness parameters in accordance with the type of competitive strategy, as well as in the form of developing a matrix for determining a competitive strategy. By summarizing the scientific research, the authors presented for scientific consideration the main parameters of differentiation of the business model of leather products, as well as the analytical scheme of cost analysis in relation to the...
12
artículo
The use of organic waste as fuel for energy generation will reduce the great environmental problems currently caused by the consumption of fossil sources, giving agribusiness companies a profitable way to use their waste. In this research, tomato waste with different percentages of sucrose (0-target, 5, 10, and 20%) was used in microbial fuel cells manufactured on a laboratory scale with zinc and copper electrodes, managing to generate maximum peaks of voltage and a current of 1.08 V and 6.67 mA in the cell with 20% sucrose, in which it was observed that the optimum operating pH was 5.29, while the MFC with 0% (target) sucrose generated 0.91 V and 3.12 A on day 13 with a similar pH, even though all the cells worked in an acidic pH. Likewise, the cell with 20% sucrose had the lowest internal resistance (0.148541 ± 0.012361 KΩ) and the highest power density (224.77 mW/cm2) at a current d...
13
artículo
“The use of organic waste as fuel for energy generation will reduce the great environmental problems currently caused by the consumption of fossil sources, giving agribusiness companies a profitable way to use their waste. In this research, tomato waste with different percentages of sucrose (0-target, 5, 10, and 20%) was used in microbial fuel cells manufactured on a laboratory scale with zinc and copper electrodes, managing to generate maximum peaks of voltage and a current of 1.08 V and 6.67 mA in the cell with 20% sucrose, in which it was observed that the optimum operating pH was 5.29, while the MFC with 0% (target) sucrose generated 0.91 V and 3.12 A on day 13 with a similar pH, even though all the cells worked in an acidic pH. Likewise, the cell with 20% sucrose had the lowest internal resistance (0.148541 ± 0.012361 KΩ) and the highest power density (224.77 mW/cm2 ) at a curr...
14
artículo
BRACKISH WATER IS AN IMPORTANT SOURCE OF WATER RESOURCES WITH LOWER SALT CONTENT THAN SEAWATER. DESALINATION IS A VERY IMPORTANT TREATMENT TO REMEDY THE SCARCITY OF FRESH WATER THROUGHOUT THE WORLD. IN THIS WORK, IT HAS BEEN PROPOSED TO DESALINATE BRACKISH GROUNDWATER USING A COMMERCIAL NANOFILTRATION MEMBRANE. THE EXPERIMENTS WERE CARRIED OUT ON THE BASIS OF A FACTORIAL DESIGN USING THREE FACTORS AND TWO LEVELS OF STUDY FOR EACH VARIABLE. FOR THIS PURPOSE, IT SELECTED THE FEED PRESSURE (X1) OF THE MEMBRANE MODULE AT (60 AND 100 PSI), FEED WATER SALINITY (X2) AT LEVELS OF (3.4 AND 6.01 MS/CM) AND OPERATING TEMPERATURE (X3) AT LEVELS (20 AND 28 °C) TO EVALUATE ITS EFFECT ON THE PERCENTAGE FLUX RECOVERY AND SALT RETENTION. THE RESULTS SHOWED THAT THE MOST SIGNIFICANT VARIABLE IS THE FEED PRESSURE, ACHIEVING HIGHER FLOW RECOVERY AND THE PERCENTAGE OF SALINITY REJECTION AT THE 100 PSI LEVEL...
15
artículo
The agronomic parameters of Tithonia diversifolia were evaluated by the effect of four cutting heights (AC) from the ground (AC1: 0 cm, AC2: 10 cm, AC3: 20 cm, AC4: 30 cm); with four replicates each, by 55 days. Shoots/tiller, leaves/shoot and leaves/tiller were higher (p<0.05) in AC1. However, the number of leaves/bush and shoots/bush were higher (p<0.05) in AC2, AC3 and AC4. The green forage weight (FV)/tiller was higher (p<0.05) in AC1; although, the weight of FV/mat was higher in AC2, AC3 and AC4, showing a higher (p<0.05) yield (kg/m2) in FV and dry matter for AC2, AC3 and AC4. The higher number of leaves/shoot (p<0.05) in AC2 than AC4 could improve the productivity of T. diversifolia, suggesting AC2 as adequate AC.
16
artículo
The use of organic waste as fuel for energy generation will reduce the great environmental problems currently caused by the consumption of fossil sources, giving agribusiness companies a profitable way to use their waste. In this research, tomato waste with different percentages of sucrose (0-target, 5, 10, and 20%) was used in microbial fuel cells manufactured on a laboratory scale with zinc and copper electrodes, managing to generate maximum peaks of voltage and a current of 1.08 V and 6.67 mA in the cell with 20% sucrose, in which it was observed that the optimum operating pH was 5.29, while the MFC with 0% (target) sucrose generated 0.91 V and 3.12 A on day 13 with a similar pH, even though all the cells worked in an acidic pH. Likewise, the cell with 20% sucrose had the lowest internal resistance (0.148541 ± 0.012361 KΩ) and the highest power density (224.77 mW/cm2) at a current ...
17
artículo
In this research a generalized inversion method was applied to obtain the epicenter of seismic events of local and regional origin from the readings of arrival time of P and S phases of at least 4 seismic stations. The initial condition of the model is obtained from the location of the seismic station closest to the epicenter, the initial origin time is obtained from the Wadati diagram and the initial depth is set up to 33 km for each case. We suppose a homogeneous velocity model of the P wave of 7.6 km/s (obtained from the inversion process). From the analysis of eigenvalues and eigenvectors of the system matrix (GTG), we deduce that the most stable parameter is the origin time and the most unstable parameter is the focal depth. The linearized model converges quickly to the solution.
18
artículo
Publicado 2018
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Tamandua (Tamandua tetradactyla) is a mammal that belongs to the superorder Xenarthra, family Myrmecophagidae, lonely animal with crepuscular habits. The objective of the study was to describe the topography, morphology, and location of the abdominal organs through an ultrasound evaluation. Five specimens of T. tetradactyla in captivity from the Huachipa Zoological Park, Lima, Peru (three adult males and two juveniles), in apparent good health conditions were used. A Pie Medical Ultrasound Falco Vet® Model 100 with a multifrequency convex transducer of 5-7.5 MHz was used. The topography, margins, shape, dimensions, echotexture and echogenicity of the abdominal organs were evaluated. The results did not differ from those found in dogs of the same size and weight. However, it has been found that the tamandua, like the Hoffmann's two-toed sloth lazy bear (Choloepus hoffmanni), has intra-ab...
19
artículo
Publicado 2013
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The objective of the study was to evaluate the effect of a mixture of organic acids and their salts on the productive parameters in broilers. A total of 133 1-day-old male chicks of the Cobb Vantress 500 Line were distributed in three treatments with three repetitions per treatment: T1, diet with Zinc-Bacitracin; T2, diet containing organic acids; and T3, control treatment, diet without growth promoter. At 42 days of age, feed conversion in T2 was 5.2% less than in T3 (p<0.05); however, no statistical differences were observed between treatments regarding body weight, body weight gain, feed consumption, mortality rate and productive efficiency index. The results showed that organic acids can efficiently replace the use of antibiotics as growth promoters in the diets of broilers
20
artículo
Publicado 2019
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The objective of this study was to determine the hematological values of Brycon amazonicus broodstock under culture in Iquitos, Peru. Blood samples were taken from 12 specimens (1.62 ± 0.45 kg and 51.38 ± 2.93 cm) maintained in earthen ponds and fed twice a day with a commercial diet with 22% crude protein. The fish were collected with a net and anesthetized with eugenol. Blood extraction was performed with disposable syringes containing EDTA (10%). The values obtained from the erythrocytic series were: hematocrit 53.3 ± 4.8%; hemoglobin 20.1 ± 3.2 g/dl; erythrocytes 2.8 ± 0.5 x106/μl; VCM 194.4 ± 54.4 fl; CHCM 37.7 ± 4.8 g/dl; HCM 72.6 ± 17.7 pg. The number of leukocytes was 8.1 ± 6.0 x103/μl. In the differential count of leukocytes, the lymphocytes and monocytes had greater proportion in comparison with neutrophils, eosinophils and basophils. The total serum protein was 3.7 ...
