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新兴经济体经济刺激方案的退出战略

金融发展评论 2010年第4期 24-29页

作者： Sonsoles Castillo José Ramón perea BBVA

动荡的金融市场更加确定了需逐步撤出的经济刺激方案策略,不过,随之可能增加经济过热风险。金融环境是怎样的?很宽松,尽管宏观调控已经实施并且全球主权危机正在加剧。新兴经济体的周期性位置是怎样的?一般来说,经济增长的势头会带来更... 详细信息

动荡的金融市场更加确定了需逐步撤出的经济刺激方案策略,不过,随之可能增加经济过热风险。金融环境是怎样的?很宽松,尽管宏观调控已经实施并且全球主权危机正在加剧。新兴经济体的周期性位置是怎样的?一般来说,经济增长的势头会带来更高的GDP预期。不过,不同国家之间存在很大的差异。

关键词：新兴经济体经济刺激退出战略货币政策新兴市场方案债务危机拉丁美洲经济过热金融危机

Embedding physics domain knowledge into a Bayesian network enables layer-by-layer process innovation for photovoltaics

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npj Computational Materials 2020年第1期6卷 1592-1600页

作者： Zekun Ren Felipe Oviedo Maung Thway Siyu I.P.Tian Yue Wang Hansong Xue Jose Dario perea Mariya Layurova Thomas Heumueller Erik Birgersson Armin G.Aberle Christoph J.Brabec Rolf Stangl Qianxiao Li Shijing Sun Fen Lin Ian Marius Peters Tonio Buonassisi Singapore-MIT Alliance for Research and Technology SMART Singapore 138602Singapore Solar Energy Research Institute of Singapore(SERIS) National University of SingaporeSingapore 117574Singapore Massachusetts Institute of Technology CambridgeMA 02139USA Institute of Materials for Electronics and Energy Technology(i-MEET) Friedrich-Alexander University Erlangen-Nürnberg91058 ErlangenGermany Helmholtz Institute HI-ErN Forschungszentrum JülichImmerwahrstrasse 291058 ErlangenGermany National University of Singapore Singapore 119077Singapore

Process optimization of photovoltaic devices is a time-intensive,trial-and-error endeavor,which lacks full transparency of the underlying physics and relies on user-imposed constraints that may or may not lead to a global ***,we demonstrate that embedding physics domain knowledge into a Bayesian network enables an optimization approach for gallium arsenide(GaAs)solar cells that identifies the root cause(s)of underperformance with layer-by-layer resolution and reveals alternative optimal process windows beyond traditional black-box *** Bayesian network approach links a key GaAs process variable(growth temperature)to material descriptors(bulk and interface properties,e.g.,bulk lifetime,doping,and surface recombination)and device performance parameters(e.g.,cell efficiency).For this purpose,we combine a Bayesian inference framework with a neural network surrogate device-physics model that is 100×faster than numerical *** the trained surrogate model and only a small number of experimental samples,our approach reduces significantly the time-consuming intervention and characterization required by the *** a demonstration of our method,in only five metal organic chemical vapor depositions,we identify a superior growth temperature profile for the window,bulk,and back surface field layer of a GaAs solar cell,without any secondary measurements,and demonstrate a 6.5%relative AM1.5G efficiency improvement above traditional grid search methods.

关键词： knowledge network enable

Support Vector Machines for Regression: A Succinct Review of Large-Scale and Linear Programming Formulations

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International Journal of Intelligence Science 2013年第1期3卷 5-14页

作者： Pablo Rivas-perea Juan Cota-Ruiz David Garcia Chaparro Jorge Arturo Perez Venzor Abel Quezada Carreón Jose Gerardo Rosiles Department of Computer Science School of Engineering & Computer Science Baylor University Waco USA Department of Electrical & Computer Engineering Autonomous University of Ciudad Juárez Ciudad Juárez México Rosiles Consulting El Paso USA

Support Vector-based learning methods are an important part of Computational Intelligence techniques. Recent efforts have been dealing with the problem of learning from very large datasets. This paper reviews the most commonly used formulations of support vector machines for regression (SVRs) aiming to emphasize its usability on large-scale applications. We review the general concept of support vector machines (SVMs), address the state-of-the-art on training methods SVMs, and explain the fundamental principle of SVRs. The most common learning methods for SVRs are introduced and linear programming-based SVR formulations are explained emphasizing its suitability for large-scale learning. Finally, this paper also discusses some open problems and current trends.

关键词： Support Vector Machines Support Vector Regression Linear Programming Support Vector Regression

Forecasting the Demand of Short-Term Electric Power Load with Large-Scale LP-SVR

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Smart Grid and Renewable Energy 2013年第6期4卷 449-457页

作者： Pablo Rivas-perea Juan Cota-Ruiz David Garcia Chaparro Abel Quezada Carreón Francisco J. Enríquez Aguilera Jose-Gerardo Rosiles Department of Computer Science School of Engineering and Computer Science Baylor University Waco USA Department of Electrical and Computer Engineering Autonomous University of Ciudad Juárez (UACJ) Ciudad Juárez México Science Applica- tions International Corporation El Paso USA.

This research studies short-term electricity load prediction with a large-scalelinear programming support vector regression (LP-SVR) model. The LP-SVR is compared with other three non-linear regression models: Collobert’s SVR, Feed-Forward Neural Networks (FFNN), and Bagged Regression Trees (BRT). The four models are trained to predict hourly day-ahead loads given temperature predictions, holiday information and historical loads. The models are trained on-hourly data from the New England Power Pool (NEPOOL) region from 2004 to 2007 and tested on out-of-sample data from 2008. Experimental results indicate that the proposed LP-SVR method gives the smallest error when compared against the other approaches. The LP-SVR shows a mean absolute percent error of 1.58% while the FFNN approach has a 1.61%. Similarly, the FFNN method shows a 330 MWh (Megawatts-hour) mean absolute error, whereas the LP-SVR approach gives a 238 MWh mean absolute error. This is a significant difference in terms of the extra power that would need to be produced if FFNN was used. The proposed LP-SVR model can be utilized for predicting power loads to a very low error, and it is comparable to FFNN and over-performs other state of the art methods such as: Bagged Regression Trees, and Large-Scale SVRs.

关键词： Power Load Prediction Linear Programming Support Vector Regression Neural Networks for Regression Bagged Regression Trees

Design and Validation of Strategy to Increasing the Rate Calving in Traditional Production System Livestock of Michoac^n M^xico Tropical Dry

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Journal of Agricultural Science and Technology(A) 2011年第8期1卷 1204-1206页

作者： G. Salas E. Garcia M. perea R. Garciduefias E. Gutierrezl A. Caratachea J. P. Flores Instituto de Investigaciones Agropecuarias y Forestales de la Universidad Michoacana de San Nico16s de Hidalgo Km. 9.5 Carretera Morelia-Zinapdcuaro Tarimbaro Michoacgm CP 58880 Mexico Facultad de Medicina Veterinaria y Zootecnia de la Universidad Michoacana de San Nicolds de Hidalgo Kin. 9.5 Carretera Morelia-Zinapdeuaro Tarimbaro Michoacdn CP 58880 Mexico

Michoacan brings 2.1% of national GDP, which is 12.5% to agriculture, Livestock is the fourth activity in economic importance in the State and develops in 43% of the territory （58,643 km：） using 27% of the population economically active. Michoacfin ranks third in national cattle inventory （1,608,523 heads） with fifth place in meat production （145,221 ton/year）. The production model is extended cow-breed, subject to season and availability of food （few rains shortage of forage during drought）, with 0.60 production of breed/cow/year, and a marked traditionalism in the form of production; also a high dependency to food based on the grazing. The inadequate national public policy expressed in the paternalism has limited the adoption of strategies to contribute to the solution of this problem. Therefore this study objective was to design and validate a strategy to increase the number of cow breeding/cow/year to season reproduction program, based on the use of synthetic progesterone ＂melengestrol acetate＂（MGA） as a technology available, secure, easy to use, low cost and likely to be adoptable to the traditional model of production. Work was done in the dry tropics in the municipalities of Churumuco and Tzitzio, Michoacfin State, Mdxico. Used 133 bovine females with crossbreeding Bos indicus, diagnosed as not pregnant, 6.7 and 6.38 years old respectively for each municipality. Oral doses of 0.05 rag/day/cow of MGA during nine days then exposed to the presence of male. Data were analyzed using analysis of variance of a single way. The results indicate that the delivery rate was 58.33% in Churumuco and 61.86% in Tzitzio. This delivery rate represents an increase of 14%-16% of born per year considering that treated females become pregnant with traditional production system management. We concluded that the MGA is an appropriate strategy to the traditional production of tropical dry in MichoacO, n system that increases the rate of births and is likely to be accepted despite th

关键词： Melengestol acetate Michoac/m tropic dry livestock percentage of births

Estrus Grouping in Sheep Treated with Melengestrol Acetate （MGA）

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Journal of Agricultural Science and Technology(A) 2011年第8期1卷 1295-1296页

作者： G. Salas F. Mata M. perea R. Garciduefias E. Gutierrez A. Caratachea J. P. Flores Instituto de Investigaciones Agropecuarias y Forestales de la Universidad Michoacana de San Nicolas de Carretera Morelia-Zinapecuaro Tarimbaro Michoacan CP 58880 Mexico Facultad de Medicina Veterinaria y Zootecnia de la Universidad Michoacana de San Nicolas de Hidalgo Morelia-Zinapecuaro Tarimbaro Michoacan CP 58880 Mexico Hidalgo Kin. 9.5 Km. 9.5 Carretera

In Mexico the predominant sheep production system is the semi-extensive with grazing during the day and stanchion afternoon and night. Sheep herd are usually small, approximately 10 to 75 heads. The objectives of these systems are savings and marketing of lambs. Meat is the main economic product of this kind, the breeding is long, which do not control the delivery dates and ages of the sheep are not uniform, affecting the demand for the local market （for the months of June and December）. Therefore the aim of this work was implement a technology that allows the grouping of the estrus and therefore group deliveries for batches of uniform lambs. This technology was designed to suppress the estrus and heifers growth promoter of feedlots, this technology is melengestrol acetate （MGA） which is a synthetic progesterone oral administration that it is easy to manage in the food or alone, economic that it does not represent any risk for sheep females of abortive type, evaluating the effect of the MGA on rate of estrus and gestation in sheep. Work developed in the municipality of Charo from Michoac^in State, M6xico, 20 hair sheep divided in two groups of 10 female, group one treated with MGA and group tow was the whitens. 100% of the sheep treated with a dose of 0.45 mg MGA/head/day for 17 days orally, presented estrus grouped in 5-10 days; however only 50% of the sheep of the witness group presented estrus. In the experimental group there was a rate of 70% with a gestation difference time of no more than ten days gestation and witness group 50%. The MGA is an efficient alternative for the producer of sheep when administered 0.45 mg MGA/head/day for 17 days because inhibits the estrus and once withdrawn treatment manifests estrus synch with which get a rate of gestation elevated by natural riding.

关键词： Melengestrol acetate sheep estrus pregnancy natural riding

Corrosion in Control Systems Decrease the Lifetime of the Electronic Devices of the Industrial Plants of Mexicali,BC,Mexico

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Open Journal of Air Pollution 2013年第2期2卷 29-35页

作者： Gustavo Lopez Badilla Maria Marcela Acosta Gomez Elizabeth Romero Samaniego Sandra Luz Toledo perea Rodolfo Thomas Guevara Garduno Carlos Omar Gutierrez Marquez Juan Pablo Quezada Hinojosa Researcher-Academic Instituto Tecnologico de Mexicali(ITM)MexicaliMexico Researcher-Academic Instituto Tecnologico de Ensenada(ITE)EnsenadaMexico Students of the Electronic Engineering Instituto Tecnologico de Mexicali(ITM)MexicaliMexico

The principal factor to determine the economical value of the products manufactured in the electronics industry is due to the productive yielding. This is important for the cost of the articles fabricated in this type of industrial plants installed in Mexicali city, where around 80% of companies are, and which fabricate electronic devices and systems, or have industrial electronic systems and machines to their manufacturing process. Mexicalicity is located in theBaja CaliforniaStateof the northwest ofMexico, which is a border city with Calexico in theCaliforniaStateof the United States of America (USA). The region located in Mexicali, is a desert area. Geothermal plant is located in this area, which is an important industry and supplies electricity to this city and its valleys and some cities on southwest of United States for daily activities. This company emits hydrogen sulfide (H2S) as a main air pollutant that reacts with oxygen in the atmosphere, generating sulfur oxides (SOX). This chemical is dispersed to the city of Mexicali in which industrial plants are located with electronic control systems, and penetrates to indoor rooms. Those cause the corrosion process. The presence of corrosion leads to the deterioration of electrical connectors, the connections of electronic systems and the decreasing of the lifetime of these control systems. Other air pollutants that are considered as chemical agents which cause damage to materials used in the electronics industry, are the sulfurs and nitrogen oxides (NOX), emitted from the traffic vehicle and some industries. This causes the low productive yielding of electrical and electronic devices and systems used in the companies of this city, and is a major concern to specialized people, managers and owners. To analyze the productive yielding of electronic devices and systems installed in indoor of the electronics industry. For this reason, to know the principal causes of it, a study in three industrial plants, to determine

关键词： Corrosion Electronic Devices Control Systems Industrial Plants

Use of Silage Acid Devil Fish （pterygoplichthys spp.） as Protein Supplement in Finishing Beef Cattle

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Journal of Agricultural Science and Technology(A) 2011年第8期1卷 1280-1283页

作者： S. Ornelas E. Gutierrez A. Juarez R. Garciduefias J. L. Espinoza M. perea J. P. Flores G. Salas Instituto de lnvestigaciones Agropecuarias y Forestales de la Universidad Michoacana de San Nicolas de Hidalgo Km 95 Carretera Morelia-Zinapecuaro 58880 Tarimbaro Michoacan Mdxico Facultad de Medicina Veterinaria y Zootecnia de la Universidad Michoacana de San Nicolas de Hidalgo Km 9.5 carretera Morelia-Zinapdcuaro 58880 Tarimbaro Michoacan Mexico Universidad Autonoma de Baja California Sur Carretera al Sur Km 5.5 Apartado Postal 19-B 23080 La Paz Baja California Sur Mexico

Animal nutrition is one of the most important limiting factors in animal production, especially in ruminants, providing proteins being the main constraint, due to the limited availability and high cost of protein sources （oilseed meals）. Currently in the dam ＂El lnfiernillo＂ in Michoacan Mexico, has a large population of devil fish （Pterygoplichthys spp.）, which is an economic and ecological problem, because it is not consumed by humans and causes pollution to be discarded directly into the environment. For that reason the objective of this study was to evaluate the use of silage acid devil fish （SADF） in fattening beef cattle as a protein supplement. SADF is defined as a product semi-liquid or pasty mixed with formic acid, which leads to a decrease in pH to near 4.0. Used 18 young bulls （Bos taurus × Bos indicus） for 60 days with a starting weight of 278.9 ± 51.2 kg, housed in individual pens with food and water ad libitum were randomly assigned to three treatments with different levels of inclusion SADF （0%, 12% and 18%）. They were weighed to the beginning of the experiment and later every 30 days, previous fasting of 24 hours. To determine the food consumption, weigh every day the offered food and the surplus. There were no significant differences （P 〈 0.05） among treatments with different levels of inclusion of SADF with respect to daily weight gain, with values of 952 ± 324, 927 ±322 and 854 ± 307 g/day, respectively. The dry matter intake （DMI） was 8.9, 9.3 and 7.7 kg/day to 0%, 12% and 18% of SADF, respectively. In the same values for feed conversion were 9.34, 10.03 and 9.01 kg DMI/kg of weigh live, and carcass yield of 60.6%, 60.3% and 58.5%, respectively. It is concluded that fish silage acid devil is an excellent alternative in feeding beef cattle as a protein supplement.

关键词： Fish silage acid devil fish finishing beef cattle.

Initial Study of Electrospinning PCL/PLLA Blends

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Advances in Materials Physics and Chemistry 2011年第3期1卷 94-98页

作者： Guinea B. C. Cardoso Geraldine N. R. perea Marcos A. D’Avila Carmen G. B. T. Dias Cecília A. C. Zavaglia Antonio C. F. Arruda 不详

The process of electrospinning is considered one of the most promising methods for the fabrication of poly- mer nanofibers. This essentially consists of applying a high electric field, which causes stretching of the polymer which exits through a capillary. Among the numerous applications of this process, electrospinning allows the fabrication of semiconductor and conductive nanofibers from mixtures or solutions, which have great potential for applications in sensors and the fabrication of scaffolds for cell growth. The aim of this work was to analyze the properties of the blend, produces by the electrospinning of the PCL and PLLA solu- tion, with the focus to generate a promissory scaffold. PCL is a semi-crystalline aliphatic polymer that has a slower degradation rate 12 - 24 months. It has a low glass transition temperature at –60?C, a melting tem-perature at about 60?C, and a high thermal stability. Properties of PLA depend on the component isomers, processing temperature, annealing time and molecular weight. Thus were used PCL, from Aldrich, with Mw of 80,000 g/mol, and PLLA, sintered in laboratory, with Mw of 240,000 g/mol, were dissolved in chloroform (CHCl3, Merck) and acetone (Synth) by stirring for 6 hours. The solution was electrospinning for 1 hour us- ing the equipment made in the laboratory, the voltage used was 13 kv, the rate of 0.5 ml/h and an approxi- mate distance from the tip of the needle to the collector of 12 cm. The morphology of the samples was ob- served by images made with scanning electron microscopy (SEM) and also was analyzed by FT-IR and DSC.

关键词： Polymers Poly (ε-Caprolactone) Poly (L-Lactic Acid) Electrospinning