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Effect of Regulated deficit Irrigation on Productivity,Quality and Water Use in Olive cv“Manzanilla”

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American Journal of Plant Sciences 2013年第12期4卷 109-113页

作者： Raúl Leonel Grijalva-Contreras Rubén Macías-duarte gerardo martínez-díaz Fabián Robles-Contreras Manuel de Jesús Valenzuela-Ruiz Fidel Nunez-Ramírez National Research Institute for Forestry Agricultural and Livestock(INIFAP)CaborcaSonoraMéxico Agricultural Science Institute University Autónoma of Baja California(ICA-UABC)MexicaliB.C.México

The objective of this experiment was to determine the effect of different regulated deficit irrigation (RdI) strategies on productivity, oil quality and water-use efficiency on olive grown in the Sonoran desert. The experiments were carried out in 2009 and 2010, and in a ten years old traditional (10 × 5 m) “Manzanilla” olive orchard. The control treatment was irrigated at 100% ETc during the whole season while RdI treatments were applied at 75% ETc or 50% ETc. The two RdI were applied during two phenological stages: at postharvest to evaluate the effect on table olive or from pit hardening to harvest to evaluate the effect on oil olive. Our results indicated that RdI applying 50% ETc during postharvest period reduced significantly fruit set and table olive yield, while applied during pit hardening to harvest period, it decreased oil yield but increased oil content. The RdI applying an ETc of 75% during the postharvest period gave similar table olive yield to the control, and applied form of pit hardening to harvest also gave similar oil yield to the control. The RdI using an ETc of 75% resulted in the highest water-use efficiency for oil or table olive production.

关键词： Olea europaea L. Water Stress Yield and Quality Water Save

Modeling and multi-objective optimization of a gasoline engine using neural networks and evolutionary algorithms

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第9期14卷 657-670页

作者： Joséd. martínez-MORALES Elvia R. PALACIOS-HERNáNdEZ gerardo A. VELáZQUEZ-CARRILLO Faculty of Engineering Autonomous University of San Luis PotosiSan Luis Potosi 78290 Mexico Faculty of Science Autonomous University of San Luis PotosiSan Luis Potosi 78290 Mexico Mechatronics department Monterrey Institute of Technology and Higher EducationMexico D. F. 01389 Mexico

In this paper, a multi-objective particle swarm optimization （MOPSO） algorithm and a nondominated sorting genetic algorithm II （NSGA-II） are used to optimize the operating parameters of a 1.6 L, spark ignition （SI） gasoline engine. The aim of this optimization is to reduce engine emissions in terms of carbon monoxide （CO）, hydrocarbons （HC）, and nitrogen oxides （NOx）, which are the causes of diverse environmental problems such as air pollution and global warming. Stationary engine tests were performed for data generation, covering 60 operating conditions. Artificial neural networks （ANNs） were used to predict exhaust emissions, whose inputs were from six engine operating parameters, and the outputs were three resulting exhaust emissions. The outputs of ANNs were used to evaluate objective functions within the optimization algorithms： NSGA-II and MOPSO. Then a decision-making process was conducted, using a fuzzy method to select a Pareto solution with which the best emission reductions can be achieved. The NSGA-II algorithm achieved reductions of at least 9.84%, 82.44%, and 13.78% for CO, HC, and NOx, respectively. With a MOPSO algorithm the reached reductions were at least 13.68%, 83.80%, and 7.67% for CO, HC, and NOx, respectively.

关键词： Engine calibration Multi-objective optimization Neural networks Multiple objective particle swarm optimization(MOPSO) Nondominated sorting genetic algorithm II (NSGA-II)

Influence of steel jacket thickness on the RC bridges' seismic vulnerability

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第1期6卷 15-34页

作者： Bertha Olmos José Manuel Jara gerardo Gómez Guillermo martínez department of Civil Engineering Universidad Michoacana de San Nicolas de Hidalgo

The seismic demands of bridges subjected to strong earthquakes are mostly concentrated on piers. The main objective of this study is to assess the seismic vulnerability of retrofitted bridges with steel jackets. It analyzes the influence of the steel jacket thickness on the seismic capacity and demand of bridges. The bridges in study have two simple supported spans with superstructure composed by AASHTO type girders and a substructure formed with one circular pier over a stiff foundation. They are located on the Pacific coast of Mexico that is a zone of high seismicity. The bridges seismic capacity are evaluated through nonlinear static analyses and the shear force and displacement demands were determined using capacity spectra with a group of 10 real accelerograms from a subduction source. The response spectra were scaled to several peak ground accelerations(PGA) with the aim to estimate four damage scenarios linked each one to a probability of exceedance in a specific period, for return periods in the range of 72-3500 years that represent service level and maximum considered earthquake. Results show that the confining effect provided by the steel jackets substantially improves the seismic performance of the bridges piers. The increase of jacket thickness guides to important increments on columns base shear capacity, and the influence of the steel jacket thickness depends on the limit state and bridge slenderness ratio.

关键词： Steel jacket Piers’retrofit Subduction earthquakes RC piers’vulnerability

Model based current mode control design and experimental validation for a 3φ rectifier under unbalanced grid voltage conditions

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Journal of Modern Power Systems and Clean Energy 2018年第4期6卷 777-790页

作者： P.R.martínez-ROdRIGEZ Jose M.SOSA Samuel ITURRIAGA-MEdINA gerardo ESCOBAR gerardo VáZQUEZ-GUZMáN Andres A.VALdEZ-FERNáNdEZ School of Sciencies UASLP Laboratory of Electrical and Power Electronics ITESI School of Engineering Universidad Modelo

This paper addresses the control design and the experimental validation of a current mode control for a three phase voltage source rectifier. The proposed control law is able to fulfill the voltage regulation and the current tracking control objectives despite of unbalanced and distorted grid voltages. The proposed control law consists of two loops, which are referred as inner tracking loop and the outer voltage regulation loop. The inner loop is designed to provide damping to the system, which also includes and adaptive mechanism. The construction of the current reference is based on the positive component detection of thegrid voltage. Therefore, the current produced by the power rectifier is proportional to the fundamental component of the grid voltage, despite of the presence of unbalanced grid voltages. The voltage regulation loop is designed as a proportional-integral controller, which is aimed to regulate the dC output voltage to a desired level. Finally, experimental results are obtained in an experimental prototype of2 kW to evaluate the performance of the proposed controller.

关键词： Pulse-width modulation rectifier Power factor correction Positive-component Current mode control

Helminth parasites of freshwater fishes from Cuatro Ciénegas,Coahuila,in the Chihuahuan desert of Mexico:inventory and biogeographical implications

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Integrative Zoology 2014年第3期9卷 328-339页

作者： Rogelio AGUILAR-AGUILAR Andrés martÍnez-AQUINO Héctor ESPINOSA-PÉREZ gerardo PÉREZ-PONCE dE LEÓN Comparative Biology department National Autonomous University of MexicoMexico CityMexico Laboratory of Helminthology National Autonomous University of MexicoMexico CityMexico Graduate Program in Biological Sciences National Autonomous University of MexicoMexico CityMexico National Collection of Fish National Autonomous University of MexicoMexico CityMexico

As part of an ongoing inventory of the helminth parasites of freshwater fishes in Mexico, 570 individual fish were collected between Apr 2008 and Oct 2011 in 26 localities along the Cuatro Ciénegas region in Coahuila State, northern Mexico. Seventeen species of hosts, mostly corresponding to Nearctic freshwater elements, were studied. A total of 8324 individual worms were collected during this survey, representing 25 species of helminths, of which 9 were digeneans, 3 monogeneans, 3 acanthocephalans, 9 nematodes and 1 cestode. Most of the records in this checklist represent new host or locality records. The information provided in this checklist may be helpful for our understanding of the biodiversity and historical biogeography of this host-parasite system, because in the Cuatro Ciénegas region occur a Nearctic freshwater fish fauna, along with Neotropical and endemic elements, and from a biogeographical point of view, this may represent a transitional area.

关键词： Acanthocephala Cestoda Cuatro Ciénegas digenea freshwater fish Mexico Monogenea Nematoda

Resource manipulation reveals flexible allocation rules to growth and reproduction in a Mediterranean evergreen oak

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Journal of Plant Ecology 2014年第1期7卷 77-85页

作者： Fernando Pulido gerardo Moreno Eustolia García José J.Obrador Raúl Bonal Mario díaz Grupo de Investigación Forestal Ingeniería Forestal y del Medio NaturalUniversidad de ExtremaduraE-10600 PlasenciaCáceresSpain Colegio de Postgraduados Campus TabascoMX-86500 CárdenasTabascoMexico Instituto de Investigación en Recursos Cinegéticos (CSIC-UCLM-JCCM)University of Castilla-La ManchaCiudad RealSpain department of Biogeography and Global Change(BCG-MNCN) Museo Nacional de Ciencias NaturalesCSICE-28006 MadridSpain

Aims In plants,resource allocation to growth and reproduction may depart from trade-off expectations if(i)investment in growth and reproduction relies on different resource pools,(ii)allocation to reproduction is dependent upon reaching some growth threshold or(iii)reproduction is developmentally linked to growth,both functions relying on the same resource *** examined the effects of enhanced resource level on patterns of resource allocation to growth and reproduction in holm oak(Quercus ilex ***),a Mediterranean evergreen *** In the experimental year(2003),we manipulated the amount of soil nutrients in autumn(to increase nutrient uptake during shoot elongation in the following spring)and soil water in summer(to increase water uptake during acorn growth).Indicators of growth and male and female reproduction were estimated in the preexperimental(2002),experimental(2003)and post-experimental(2004)*** Findings Fertilized trees produced significantly longer shoots,but the number of female flowers per shoot was not affected by *** production of male catkins was also enhanced by *** did not affect the production of female flowers or abortion *** and female reproduction showed no consistent relationship in untreated trees,but resource addition elicited a growth-female reproduction trade-off in the experimental *** sign of this significant relationship changed in the post-experimental year,indicating the existence of lagged effects of resource manipulation on acorn ***,patterns of allocation to growth and reproduction varied as a function of sex,resource availability and year,a result consistent with extreme allocational plasticity in holm oak.

关键词： acorn abortion allocational plasticity dehesa growthreproduction trade-offs nutrient addition Quercus ilex resource allocation

Experiment design for the Location-Allocation Problem

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Applied Mathematics 2014年第14期5卷 2168-2183页

作者： María Beatríz Bernábe Loranca Rogelio González Velázquez martín Estrada Analco Mario Bustillo díaz gerardo martínez Guzman Abraham Sánchez López Computer Science department Benemérita Universidad Autónoma de Puebla Puebla México

The allocation of facilities and customers is a key problem in the design of supply chains of companies. In this paper, this issue is approached by partitioning the territory in areas where the distribution points are allocated. The demand is modelled through a set of continuous functions based on the population density of the geographic units of the territory. Because the partitioning problem is NP hard, it is necessary to use heuristic methods to obtain reliable solutions in terms of quality and response time. The Neighborhood Variable Search and Simulated Annealing heuristics have been selected for the study because of their proven efficiency in difficult combinatorial optimization problems. The execution time is the variable chosen for a factorial experimental design to determine the best-performing heuristics in the problem. In order to compare the quality of the solutions in the territorial partition, we have chosen the execution time as the common parameter to compare the two heuristics. At this point, we have developed a factorial statistical experimental design to select the best heuristic approaches to this problem. Thus, we generate a territorial partition with the best performing heuristics for this problem and proceed to the application of the location-allocation model, where the demand is modelled by a set of continuous functions based on the population density of the geographical units of the territory.

关键词： demand Experimental design Heuristics Location-Allocation Partitioning.

Effect of Aging in the Structure of Silica Xerogels with Incorporation of Extract’s Leaves

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New Journal of Glass and Ceramics 2011年第1期1卷 7-12页

作者： José R. martínez Erika Espericueta gerardo Ortega-Zarzosa 不详

The spectral fluorescence characteristics of extracts leaves embedded in silica xerogel matrix promoted by aged time was studied. We obtain a higher PSII stability for extract of leaves embedded in xerogel matrix, with concentration of 8 g / 20 ml and water to TEOS molar ratio of 11, which remain bioactive over a very long period of time, whereas for a water to TEOS molar ratio of 5 a blue-shift fluorescence is observed indicating the PSII denaturizing and formation of fluorescing aggregates associated with the activation of carotenoids radicals.

关键词： Fluorescence Spectra Sol-Gel Chlorophyll Extract Leaves Photosystem II

Fabrication and testing of polymer-based capacitive micromachined ultrasound transducers for medical imaging

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Microsystems & Nanoengineering 2018年第1期4卷 178-189页

作者： Carlos d.gerardo Edmond Cretu Robert Rohling department of Electrical and Computer Engineering University of British Columbia2332 Main MallVancouverBCCanada department of Mechanical Engineering University of British Columbia6250 Applied Science LnVancouverBCCanada

The ultrasonic transducer industry is dominated by piezoelectric *** an emerging alternative,capacitive micromachined ultrasound transducers(CMUTs)offer wider bandwidth,better integration with electronics,and ease of fabricating large *** have a sealed cavity between a fixed electrode and a suspended metalized *** cost and sensitivity are limiting factors in current CMUTs that depend on the fabrication equipment and,especially,on the materials *** widespread use of CMUTs,a much lower fabrication cost that uses inexpensive materials,which maintain or improve upon existing sensitivity,is ***,a new fabrication process is described for polymer-based CMUTs(polyCMUTs)using the photopolymer SU-8 and *** first ultrasound B-mode image of a wire phantom created with a 64-element linear array using synthetic aperture beamforming techniques is presented.A 12 VAC signal superimposed on a 10 VdC signal was used on the transmission side,and only a bias-tee,with no amplifiers,was used on the receiving *** low operational voltage and high sensitivity of this device can be partially attributed to a pre-biasing condition on the *** using a novel sacrificial layer combined with a top electrode embedded inside the membrane,we demonstrated that SU-8 can be used to manufacture CMUTs ***,the fabrication used relatively simple equipment,and the number of fabrication steps was reduced compared to traditional CMUT *** new fabrication process has the potential to increase the use of CMUTs in the ultrasound market,including the market for wearable transducers.

关键词： polymer electrode testing