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Approximate Kerr-Like Metric with Quadrupole  [PDF]
Francisco Frutos-Alfaro
International Journal of Astronomy and Astrophysics (IJAA) , 2016, DOI: 10.4236/ijaa.2016.63028
Abstract: A new approximate metric representing the spacetime of a rotating deformed body is obtained by perturbing the Kerr metric to include up to the second order of the quadrupole moment. It has a simple form, because it is Kerr-like. Its Taylor expansion form coincides with second order quadrupole metrics with slow rotation already found. Moreover, it can be transformed to an improved Hartle-Thorne metric, which guarantees its validity to be useful in studying compact object, and it is possible to find an inner solution.
Marriage in Honey Bees Optimization Algorithm for Flow-shop Problems
Pedro PALOMINOS,Francisco TOLEDO,Andrés VéJAR,Miguel ALFARO
Informatica Economica Journal , 2012,
Abstract: The objective of this work is to make a comparative study of the Marriage in Honeybees Op-timization (MBO) metaheuristic for flow-shop scheduling problems. This paper is focused on the design possibilities of the mating flight space shared by queens and drones. The proposed algorithm uses a 2-dimensional torus as an explicit mating space instead of the simulated an-nealing one in the original MBO. After testing different alternatives with benchmark datasets, the results show that the modeled and implemented metaheuristic is effective to solve flow-shop type problems, providing a new approach to solve other NP-Hard problems.
Efecto de Diferente Dosis de Lodo de la Crianza de Salmones en el Cultivo de Papa y su Efecto Residual en Ballica Anual
Teuber K,Nolberto; Salazar S,Francisco; Alfaro V,Marta; Valdebenito B,Aldo;
Agricultura Técnica , 2007, DOI: 10.4067/S0365-28072007000400007
Abstract: intensive salmon farming generates organic residues which have a potential use in agricultural soils. the objective of this study was to evaluate the effect of three salmon sludge rates on potato (solanum tuberosum) crop development and its residual effect on annual ryegrass (lolium multiflorum). the field experiment was carried out on an andisoil from osorno serie (hapludands), located in osorno (40o35？s, 73o08？w), chile. treatment were three salmon sludge rates (50, 100, 200 t ha-1), a control (no fertilizer), and an inorganic fertilizer treatment. the salmon sludge was incorporated into the soil and then potato tubers cv. yagana-inia were planted. after the harvest, an annual ryegrass was seeded. total potato yield with inorganic fertilizer was 64.3 t ha-1, significantly superior to the results with the salmon sludge rates and the control (p ≤ 0.05). there were no differences (p > 0.05) among the fish sludge rates (45.6 to 47.5 t ha-1) and the control treatment (39.4 t ha-1). in addition, there were no differences (p > 0.05) on tuber weight, but the number of tubers per plant was different (p ≤ 0.05). annual ryegrass yield was significantly different (p ≤ 0.05) between fertilizer treatments and the control. salmon sludge did not affect potato or ryegrass yield or development and increased p olsen and cation exchange capacity in the soil.
EL traslado fallido del Aeropuerto Internacional de la Ciudad de México a Texcoco
Alfaro Izarraraz, Rafael;Guízar Vázquez, Francisco;Vizcarra Bordi, Ivonne;
Argumentos (México, D.F.) , 2011,
Abstract: this article discusses the objectives, resource and exploitation of the stage, used by government and by social movements in san salvador atenco, as some of the causes that explain, in the context of desocialization, the failure to relocate the airport in the texcoco region. the study is based on a qualitative approach. it notes the government's inability to act in a context of great changes, which drove him to cancel the airport project.
NITROGEN LEACHING LOSSES ON A VOLCANIC ASH SOIL AS AFFECTED BY THE SOURCE OF FERTILISER
Alfaro V,Marta; Salazar S,Francisco; Endress B,Denisse; Dumont L,Juan C; Valdebenito B,Aldo;
Revista de la ciencia del suelo y nutrición vegetal , 2006, DOI: 10.4067/S0718-27912006000200005
Abstract: an intact lysimeters study was carried out to measure the potential nitrogen (n) losses on an andisoil of southern chile with different fertilisers. the treatments tested were: fish slurry (fs), dairy slurry (ds), potassium nitrate (if) and a control treatment (c), with no n addition. an equivalent amount of 150 kg of total n ha-1 was applied to each lysimeter and then the equivalent to 1260 mm of rainfall was irrigated over a 90 days period. leachate samples were analysed for nitrate, nitrite, ammonia and organic n (no). total n losses were calculated as the product between drainage and the respective n concentration in the leachates. lowest n losses were obtained in the control and fs treatments (66 kg n ha-1) and the greatest amount was obtained in the if treatment (261 kg n ha-1). nitrogen was mainly lost as nitrate and no (each was 49% of the total n losses). high soil organic matter of andisoils can be more relevant than fertiliser for n leaching losses.
El traslado fallido del Aeropuerto Internacional de la Ciudad de México a Texcoco
Rafael Alfaro Izarraraz,Francisco Guízar Vázquez Jr.,Ivonne Vizcarra Bordi
Argumentos (México, D.F.) , 2011,
Abstract: en este artículo se analizan objetivos, recursos y aprovechamiento del escenario, usados por el gobierno así como por el movimiento social de San Salvador Atenco, como algunas de las causas que explican, en el contexto de la desocialización, el fracaso por reubicar la terminal aérea en la región de Texcoco. El estudio se basa en un enfoque cualitativo. Se observa la incapacidad del gobierno para actuar, en un contexto de grandes transformaciones, que lo orillaron a cancelar el proyecto aeroportuario.
NITROGEN LEACHING LOSSES ON A VOLCANIC ASH SOIL AS AFFECTED BY THE SOURCE OF FERTILISER Pérdidas de nitrógeno por lixiviación por efecto de la fuente del fertilizante en un suelo derivado de cenizas volcánicas
Marta Alfaro V,Francisco Salazar S,Denisse Endress B,Juan C Dumont L
Revista de la Ciencia del Suelo y Nutrición Vegetal , 2006,
Abstract: An intact lysimeters study was carried out to measure the potential nitrogen (N) losses on an andisoil of Southern Chile with different fertilisers. The treatments tested were: fish slurry (FS), dairy slurry (DS), potassium nitrate (IF) and a control treatment (C), with no N addition. An equivalent amount of 150 kg of total N ha-1 was applied to each lysimeter and then the equivalent to 1260 mm of rainfall was irrigated over a 90 days period. Leachate samples were analysed for nitrate, nitrite, ammonia and organic N (No). Total N losses were calculated as the product between drainage and the respective N concentration in the leachates. Lowest N losses were obtained in the control and FS treatments (66 kg N ha-1) and the greatest amount was obtained in the IF treatment (261 kg N ha-1). Nitrogen was mainly lost as nitrate and No (each was 49% of the total N losses). High soil organic matter of andisoils can be more relevant than fertiliser for N leaching losses. Un experimento con lisímetros intactos se llevó a cabo para medir el potencial de pérdida de nitrógeno (N) en un andisol del sur de Chile con diferentes fertilizantes. Los tratamientos evaluados fueron purín de pescado (FS), purín de lechería (DS), nitrato de potasio (IF) y un tratamiento control (C), sin adición de N. Se aplicó una dosis equivalente a 150 kg ha-1 de N total a cada lisímetro y luego estos fueron regados con el equivalente a 1260 mm de lluvia distribuida en un periodo de 90 días. Las muestras de lixiviado fueron analizadas para nitrato, nitrito, amonio y N orgánico (No). Las pérdidas totales de N fueron calculadas como el producto del drenaje colectado y su respectiva concentración de N en la muestra. Las pérdidas más bajas de N se obtuvieron en el tratamiento control y en el tratamiento FS (66 kg N ha-1), y las pérdidas más altas se obtuvieron el tratamiento IF (261 kg N ha-1). El nitrógeno fue perdido principalmente como nitrato y como No (cada uno representó el 49% del total de las pérdidas). El alto contenido de materia orgánica de un andisol puede ser más relevante para las pérdidas de N por lixiviación que el tipo de fertilizante utilizado.
Efecto de Diferente Dosis de Lodo de la Crianza de Salmones en el Cultivo de Papa y su Efecto Residual en Ballica Anual Effect of Different Rates of Cage Salmon Sludge on Potato Crop and its Residual Effect on Annual Ryegrass
Nolberto Teuber K,Francisco Salazar S,Marta Alfaro V,Aldo Valdebenito B
Agricultura Técnica , 2007,
Abstract: La producción intensiva de salmones genera residuos orgánicos que tienen un uso potencial en suelos agrícolas, existiendo escasa información publicada de su utilización. El objetivo del presente estudio fue evaluar el efecto de tres dosis de lodo de salmón en el desarrollo del cultivo de papa (Solanum tuberosum) y su efecto residual en ballica anual (Lolium multiflorum). El ensayo se estableció en un suelo Andisol de la serie Osorno (Typic Hapludands), ubicado en Osorno (40o35’S, 73o08’O), Chile. Los tratamientos fueron tres dosis de lodo (50, 100 y 200 t ha-1), un control (sin fertilización orgánica e inorgánica) y un tratamiento de fertilización inorgánica. El lodo se incorporó al suelo, posteriormente se plantó papa cv. Yagana-INIA y después de la cosecha se sembró ballica anual cv. Sabalan. El rendimiento de papa con fertilización inorgánica fue 64,3 t ha-1, superior a los resultados obtenidos con las dosis de lodo y el control (P ≤ 0,05). No hubo diferencias estadísticas (P > 0,05) entre las distintas dosis de lodo evaluadas (45,6 a 47,5 t ha-1) y tampoco con el control (39,4 t ha-1). No se observaron diferencias (P > 0,05) en el peso por tubérculo, pero el número de tubérculos por planta fue diferente (P ≤ 0,05). El rendimiento de ballica anual fue significativamente diferente (P ≤ 0,05) en los tratamientos fertilizados comparados con el control. El lodo no afectó la emergencia ni el desarrollo de los cultivos, pero incrementó el contenido de P Olsen y la suma de bases de intercambio en el suelo. Intensive salmon farming generates organic residues which have a potential use in agricultural soils. The objective of this study was to evaluate the effect of three salmon sludge rates on potato (Solanum tuberosum) crop development and its residual effect on annual ryegrass (Lolium multiflorum). The field experiment was carried out on an Andisoil from Osorno Serie (Hapludands), located in Osorno (40o35’S, 73o08’W), Chile. Treatment were three salmon sludge rates (50, 100, 200 t ha-1), a control (no fertilizer), and an inorganic fertilizer treatment. The salmon sludge was incorporated into the soil and then potato tubers cv. Yagana-INIA were planted. After the harvest, an annual ryegrass was seeded. Total potato yield with inorganic fertilizer was 64.3 t ha-1, significantly superior to the results with the salmon sludge rates and the control (P ≤ 0.05). There were no differences (P > 0.05) among the fish sludge rates (45.6 to 47.5 t ha-1)and the control treatment (39.4 t ha-1). In addition, there were no differences (P > 0.05) on tuber weight, but the num
Ganadería y Contaminación Difusa, Implicancias para el Sur de Chile
Alfaro,Marta; Salazar,Francisco;
Agricultura Técnica , 2005, DOI: 10.4067/S0365-28072005000300012
Abstract: as a result of the free trade agreements signed by chile, which will open markets for the export of dairy and beef products, it is expected that the livestock production activity will be increased and intensified in southern chile. despite the technological knowledge available for livestock production in the area, little is known about the environmental impact of this activity, especially on surface waters, in spite of the fact that the rivers and lakes of the region are also the main resources for other important economic activities, such as aquaculture and tourism. in developed countries it has been shown that there is a strong cause-effect relationship between livestock production and diffuse pollution of surface waters, especially in relation to the eutrophication of these resources, because of high nitrogen (n) and phosphorous (p) concentrations. if an analysis of the mechanisms controlling n and p losses from livestock systems to waters is made, it is possible to develop a possible scenario for the lake district of southern chile. the greater number of inputs, the use of increasing stocking rates, the lack of best management practices and the incorporation of hilly areas or where artificial drainage has been incorporated, will probably result in low efficiency in the use of both the n and p incorporated into the livestock systems as fertilizers, increasing their losses, and in turn resulting in the eutrophication of nearby water resources.
LIVESTOCK PRODUCTION AND DIFFUSE POLLUTION IN A VOLCANIC SOIL
Alfaro,Marta; Salazar,Francisco;
Revista de la ciencia del suelo y nutrición vegetal , 2008, DOI: 10.4067/S0718-27912008000200002
Abstract: in developed countries, intensive grazing has been related to water pollution. the results of several projects carried out on a volcanic soil of the osorno soil series on beef grazing production systems have shown that grazing management did not increase total nitrogen (n) and phosphorus (p) transfer and losses. due to the high water infiltration capacity of the soil, runoff was <1% of total drainage, therefore, n and p losses in runoff were small. nitrogen leaching losses were high (3 up to 71 kg n ha-1 yr-1). nitrogen loss in runoff was mainly lost as don (c. 50%) while n leaching losses were mainly as nitrate (c. 70%). total p losses ranged between 1 and 22 g p ha-1 yr-1 and they increased with increasing field slopes. phosphorus was mainly lost as reactive p (c. 70%). total losses were greatly affected by incidental n and p losses associated to spring n and p fertilizer application, so that grassland managements should consider this constrain for grazed areas in southern chile. research should be carried out in more intensive production systems (e.g. dairy farms) where n and p rates used are higher and applied during different times of the year, with a potential impact for the wider environment.
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