Browsing by Type "Book Series"
  • Publication
    An binary black hole algorithm to solve set covering problem
    ( 2016-01-01)
    Rubio Á.
    ;
    Crawford B.
    ;
    Soto R.
    ;
    Jaramillo A.
    ;
    Villablanca S.
    ;
    Salas J.
    ;
    Olguín E.
    The set covering problem (SCP) is one of the most representative combinatorial optimization problems and it has multiple applications in different situations of engineering, sciences and some other disciplines. It aims to find a set of solutions that meet the needs defined in the constraints having lowest possible cost. In this paper we used an existing binary algorithm inspired by Binary Black Holes (BBH), to solve multiple instances of the problem with known benchmarks obtained from the OR-library. The presented method emulates the behavior of these celestial bodies using a rotation operator to bring good solutions. After tray this algorithm, we implemented some improvements in certain operators, as well as added others also inspired by black holes physical behavior, to optimize the search and exploration to improving the results.
  • Publication
    Automatic triggering of constraint propagation
    ( 2013-01-01)
    Monfroy E.
    ;
    Crawford B.
    ;
    Soto R.
    A constraint satisfaction problem requires a value, selected from a given finite domain, to be assigned to each variable in the problem, so that all constraints relating the variables are satisfied. The main feature of any constraint solver is constraint propagation, it embeds any reasoning which consists in explicitly forbidding values or combinations of values for some variables of a problem because a given subset of its constraints cannot be satisfied otherwise. It is very important to apply constraint propagation as efficiently as possible. In this paper, we present a hybrid solver based on a Branch and Bound algorithm combined with constraint propagation to reduce the search space. Some rules trigger constraint propagation based on some observations of the solving process. The results show that is possible to make reasonable use of constraint propagation. © 2013 Springer-Verlag Berlin Heidelberg.
  • Publication
    B-EDCA: A new IEEE 802.11e-based QoS protocol for multimedia wireless communications
    ( 2006-01-01)
    Villaón J.
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    Cuenca P.
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    Orozco-Barbosa L.
    The IEEE 802.11e draft standard is a proposal defining the mechanisms for wireless LANs aiming to provide QoS support to time-sensitive applications. However, recent studies have shown that the IEEE 802.11e (EDCA) performs poorly when the medium is highly loaded due to the high collision rate. Even though several proposals have been proposed to address this problem, they require important changes to the current standard specifications making difficult their actual implementation. In this paper, we propose a simple QoS-aware mechanism and fully compatible with the various operation modes of the EDCA standard as well as the legacy IEEE 802.11 (DCF) scheme. Our design has been based on an in-depth analysis of the several operation modes of both standards. This should ensure full compatibility of operation: an important feature since the transition from the IEEE 802.11 to the IEEE 802.11e will take some time making more likely the existence of hybrid scenarios where both standards will have to coexist. Our simulation results show that our new scheme outperforms the EDCA and other QoS-aware schemes recently reported in the literature. © IFIP International Federation for Information Processing 2006.
  • Publication
    Conventional banana and plantain breeding
    ( 2013-04-25)
    Ortiz R.
    Cross-breeding of banana and plantain brings new challenges to the genetic improvement of crops due to the ploidy and high sterility of most popular cultivars. This article provides an overview of the current status of banana and plantain breeding. It also provides details on the approaches used and steps throughout the breeding process: crossing, screening, testing, selecting and identifying promising hybrids for further cultivar releases. This manuscript also highlights the genetic knowledge accumulated in this crop that will facilitate the use of new approaches in its improvement. Banana and plantain breeding programs may incorporate genetic engineering and genomics-led breeding to enhance their effectiveness, particularly under a changing climate that is likely to affect crop yields.
  • Publication
    Efficiently mining gapped and window constraint frequent sequential patterns
    ( 2020-01-01)
    Alatrista-Salas H.
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    Guevara-Cogorno A.
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    Maehara Y.
    ;
    Nunez-del-Prado M.
    Sequential pattern mining is one of the most widespread data mining tasks with several real-life decision-making applications. In this mining process, constraints were added to improve the mining efficiency for discovering patterns meeting specific user requirements. Therefore, the temporal constraints, in particular, those that arise from the implicit temporality of sequential patterns, will have the ability to efficiently apply temporary restrictions such as, window and gap constraints. In this paper, we propose a novel window and gap constrained algorithms based on the well-known PrefixSpan algorithm. For this purpose, we introduce the virtual multiplication operation aiming for a generalized window mining algorithm that preserves other constraints. We also extend the PrefixSpan Pseudo-Projection algorithm to mining patterns under the gap-constraint. Our performance study shows that these extensions have the same time complexity as PrefixSpan and good linear scalability.
  • Publication
    Food, Nutrition and Agrobiodiversity Under Global Climate Change
    ( 2013-01-01)
    Dwivedi S.
    ;
    Sahrawat K.
    ;
    Upadhyaya H.
    ;
    Ortiz R.
    Available evidence and predictions suggest overall negative effects on agricultural production as a result of climate change, especially when more food is required by a growing population. Information on the effects of global warming on pests and pathogens affecting agricultural crops is limited, though crop-pest models could offer means to predict changes in pest dynamics, and help design sound plant health management practices. Host-plant resistance should continue to receive high priority as global warming may favor emergence of new pest epidemics. There is increased risk, due to climate change, to food and feed contaminated by mycotoxin-producing fungi. Mycotoxin biosynthesis gene-specific microarray is being used to identify food-born fungi and associated mycotoxins, and investigate the influence of environmental parameters and their interactions for control of mycotoxin in food crops. Some crop wild relatives are threatened plant species and efforts should be made for their in situ conservation to ensure evolution of new variants, which may contribute to addressing. new challenges to agricultural production. There should be more emphasis on germplasm enhancement to develop intermediate products with specific characteristics to support plant breeding. Abiotic stress response is routinely dissected to component physiological traits. Use of transgene(s) has led to the development of transgenic events, which could provide enhanced adaptation to abiotic stresses that are exacerbated by climate change. Global warming is also associated with declining nutritional quality of food crops. Micronutrient-dense cultivars have been released in selected areas of the developing world, while various nutritionally enhanced lines are in the release pipeline. The high-throughput phenomic platforms are allowing researchers to accurately measure plant growth and development, analyze nutritional traits, and assess response to stresses on large sets of individuals. Analogs for tomorrow's agriculture offer a virtual natural laboratory to innovate and test technological options to develop climate resilience production systems. Increased use of agrobiodiversity is crucial to coping with adverse impacts of global warming on food and feed production and quality. No one solution will suffice to adapt to climate change and its variability. Suits of technological innovations, including climate-resilient crop cultivars, will be needed to feed 9 billion people who will be living in the Earth by the middle of the twenty-first century. © 2013 Elsevier Inc.
  • Publication
    Lean Manufacturing Application in the Laminating Machine Manufacturing Process in a Metalworking Company
    (Springer Science and Business Media Deutschland GmbH, 2021-01-01)
    Camacho Sanchez K.E.
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    Saavedra Rosales J.J.
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    Salvatierra Garcia Y.
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    QUISPE SANTIVAÑEZ, GRIMALDO WILFREDO
    This study describes an improvement implementation in the manufacturing process of a laminating machine using lean manufacturing tools. After identifying the activities that do not add value to the process, the Ishikawa diagram and Pareto diagram were applied to determine the potential causes of it. Finally, the visual board, the 5 S, and the poka-yoke were successfully implemented, achieving a 25-day reduction in the manufacturing process time, which represents an efficiency of 36.57%.
  • Publication
    Platalina genovensium (Chiroptera: Phyllostomidae)
    ( 2020-12-15)
    Ossa G.
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    ZAMORA MEZA, HUGO TOMAS
    ;
    Velazco P.M.
    Platalina genovensium Thomas, 1928 is a bat commonly called Peruvian long-tongued bat. P. genovensium is characterized by having a greatly elongated muzzle, rostrum clearly longer than the braincase, and premaxillary bones projecting beyond the canines. The dorsal pelage is long and bicolored; the venter is lighter than the dorsum. P. genovensium is distributed from west of the Andes in Peru to northern Chile, with a few records reported from the Andes in Peru. It feeds in desert areas characterized by the presence of columnar cacti from which it obtains nectar and fruits; it has been recorded at elevations from near sea level up to about 2,600 m. It is listed as “Near Threatened” by the International Union for Conservation of Nature and Natural Resources.
  • Publication
    Preface
    (Springer Science and Business Media Deutschland GmbH, 2022-01-01)
    Emrouznejad A.
    ;
    CHARLES, VINCENT
  • Publication
    Probability Theory
    (Springer, 2022-01-01)
    Amirteimoori A.
    ;
    Sahoo B.K.
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    CHARLES, VINCENT
    ;
    Mehdizadeh S.
    Probability theory is a branch of mathematical science that deals with the mathematical analysis of random events. Probability is commonly used to describe the mind’s attitude to statements that we are not sure of. Statements usually take the form of “Will a particular event occur?” and the attitude of our minds will be of the form “How confident are we that this event will occur?” Our confidence can be described numerically, which is a value between 0 and 1 that we call probability. The more likely to occur an event is, the more confident we are that it will occur. The focus in this chapter is mainly on probability space, random variable, multi-dimensional probability distribution, expected value, variance, and covariance.
  • Publication
    Seismic Assessment of the Church of San Sebastian in Cusco, Peru by Means of Pushover Nonlinear Analysis
    (Springer Netherlands, 2019)
    NOEL TAPIA, MARIA FERNANDA
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    Moreira S.
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    BRICEÑO MELENDEZ, CAROLINA PAOLA
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    LOPEZ HURTADO ORJEDA, LUIS ENRIQUE
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    AGUILAR VELEZ, RAFAEL
    The present paper seeks to evaluate the seismic performance of the San Sebastian church and its vulnerability to seismic events. This colonial temple dates back to the 16th century and is located in Cusco, Perú. The church stands out for being one of the first five Andean temples erected in the city of Cusco and also for being one of the most outstanding expressions of baroque art. Due to its artistic and cultural value, this church was declared National Cultural Heritage in 1972. Unfortunately, the periodic occurrence of seismic events and a fateful fire occurred in 2016 have endangered the survival of the structure and the safety of visitors. Aiming to evaluate the current situation of the church, this research developed a pathological identification through visual inspection and IR thermography as a non-destructive technique. A numerical analysis was also performed by means of a nonlinear pushover analysis that allowed estimating the evolution of the damage and the capacity of the structure in a seismic event. The results of the analysis showed that the main failure mechanisms of the structure would be the decoupling of the church front portion (towers and choir), generating concentrated damage in the arches that support the choir, as well as longitudinal cracks in the nave walls. The seismic capacity related to these failures is around 0.20 g, which is much lower than the recommended demand from the Peruvian code for the region of Cusco – 0.25 g – meaning that the church is highly vulnerable to seismic loads.
  • Publication
    Semantic Segmentation of Underwater Environments Using DeepLabv3+ and Transfer Learning
    ( 2022-01-01)
    Chicchon M.
    ;
    BEDON MONZON, HECTOR MANUEL
    The semantic segmentation approach is essential in automated scene analysis, but its application in underwater environments is still limited. Datasets generally have insufficient labeled data, unbalanced data classes, and different lighting conditions, making it difficult to obtain optimal results. Currently, deep convolutional neural networks allow very good results in machine vision tasks, and one of the network architectures with good performance in semantic segmentation is DeepLabv3 +. This paper evaluates the performance of DeepLabv3 + and transfer learning based on pre-trained backend networks in ImageNet to study underwater scenes. The experimentation is carried out on a dataset available on the Internet with labels of eight classes. Experimental results show that DeepLabv3 + and transfer learning are effective for semantic segmentation of multiple underwater scene objects with insufficient tagged data and unbalanced classes.
  • Publication
    Semantic Segmentation of Weeds and Crops in Multispectral Images by Using a Convolutional Neural Networks Based on U-Net
    ( 2020-01-01)
    Chicchón Apaza M.Á.
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    BEDON MONZON, HECTOR MANUEL
    ;
    Garrido R.P.A.
    A first step in the process of automating weed removal in precision agriculture is the semantic segmentation of crops, weeds and soil. Deep learning techniques based on convolutional neural networks are successfully applied today and one of the most popular network architectures in semantic segmentation problems is U-Net. In this article, the variants in the U-Net architecture were evaluated based on the aggregation of residual and recurring blocks to improve their performance. For training and testing, a set of data available on the Internet was used, consisting of 60 multispectral images with unbalanced pixels, so techniques were applied to increase and balance the data. Experimental results show a slight increase in quality metrics compared to the classic U-Net architecture.
  • Publication
    Solving the set covering problem with binary cat swarm optimization
    ( 2015-01-01)
    Crawford B.
    ;
    Soto R.
    ;
    BerrÍos N.
    ;
    Johnson F.
    ;
    Paredes F.
    The Set Covering Problem is a formal model for many practical optimization problems. It consists in finding a subset of columns in a zero–one matrix such that they cover all the rows of the matrix at a minimum cost. To solve the Set Covering Problem we use a metaheuristic called Binary Cat Swarm Optimization. This metaheuristic is a binary version of Cat Swarm Optimization generated by observing cat behavior. Cats have two modes of behavior: seeking mode and tracing mode. We are the first ones to use this metaheuristic to solve the Set Covering Problem, for this the proposed algorithm has been tested on 65 benchmarks instances.
  • Publication
    The effect of pre-culture temperature treatment on the cryopreservation of potato shoot-tips
    (International Society for Horticultural Science, 2011-09-30)
    PANTA LALOPU, ANA LUZ
    ;
    Tay D.
    ;
    Ynouye C.
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    ROCA PIZZINI, WILLIAM MANUEL
    The International Potato Center's (CIP) genebank was established following its foundation in 1971. Currently, 4,607 accessions of 7 cultivated potato species are maintained clonally as tuber, in vitro, cryo- and DNA collections in CIP genebank. In January 2008, CIP's genebank became the first worldwide to obtain an ISO 17025 accreditation for its in vitro germplasm conservation and distribution systems. The cryo-bank is an integrated part of the total genebank safety backup management system. The vitrification protocol developed by Steponkus at Cornell University was applied to 400 potato genotypes, and 121 accessions were successfully cryopreserved. During 2004-2006, with an aim of establishing a cryo-bank for a long-term conservation of potato landraces, research for improving cryo-procedures was conducted and as result a revised PVS2 vitrification method was developed. Currently, the droplet PVS2 vitrification method is the preferred procedure applied to place the 4,607 accessions of cultivated potatoes into the cryo-bank. Testing 434 potato accessions and using both, 6 and 22°C pre-culture treatments, 92% showed recovery frequency of at least 5%; out of them 67% reached at least 20% recovery. This protocol increased the range of genotypes showing positive post-thawing recovery, and rendered suitable for the long-term conservation of widely diverse potato genotypes, with shoot-tips' recovery rates of 20-100% in two replicated lots of 50 shoot-tips each.
  • Publication
    The role of extension services for the successful introduction of new Musa cultivars in southeastern Nigeria
    (International Society for Horticultural Science, 2000-01-01)
    Akele S.
    ;
    Isirimah N.
    ;
    Brisibe A.
    ;
    Ortiz R.
    Black sigatoka causes yield losses of 30 to 50% in banana and plantain. The cultivation of resistant cultivars is the most appropriate intervention to control this fungal leaf spot disease in Africa. The short-term approach of the International Institute of Tropical Agriculture (IITA) to control black sigatoka in Nigeria was to identify, multiply and distribute resistant cooking bananas. The Green River Project (GRP), in collaboration with IITA, has been promoting cooking bananas as a substitute for plantain in southeastern Nigeria. Five rural areas in the northern part of Rivers State (Omoku/Kreigani, Obrikom-Obie-Obor-Ebeghoro, Ebocha, Mgbede/ Aggah and Okwuzi) are served by GRP. An extension officer and a rural assistant officer are responsible for transferring new techniques and cultivars to the farming community. Local farmers are regularly informed, through practical demonstrations, how to improve their current cultural practices and how to incorporate new products into their diets. Since local consumers were not accustomed to cooking bananas, the extension officers carried out palatability tests to show how this new product may be cooked and eaten. Farmers and consumers indicated that cooking bananas had smaller and softer fruits, longer cooking time and lower starch than plantains. Nonetheless, farmers are gradually accepting cooking bananas as substitute of plantain because of their resistance to black sigatoka. Hence, GRP has multiplication plots for further distribution of cooking banana suckers to farmers. The success for adoption of cooking bananas by the farming community in southeastern Nigeria will depend on creating public awareness and encouraging the planting of black sigatoka resistant cooking bananas among local farmers. This will need adequate extension services which should provide planting materials with high health status and proper technology for storage and enhanced utilization of cooking bananas after harvest. This experience with cooking bananas may provide means for a successful and fast distribution to the Nigerian farmers of new plantain or banana hybrid cultivars when they become available.
  • Publication
    The role of horticulture: Issues, opportunities and constraints
    (International Society for Horticultural Science, 2003-07-01)
    MWANGA, ROBERT O.M.
    ;
    Cloete M.
    The world's population is projected at 9 billion by the year 2030. Most of the increase in population will be in developing countries in Latin America, Asia, and Africa, where chronic food shortages and malnutrition persist. Horticulture is underdeveloped in most African countries. The regions food priorities can be addressed by focusing attention on important horticultural crops and critical issues. Key issues include, food shortage, distribution, nutrition, competitive advantage of individual countries or regions, local and export marketing constraints, and industry strategic planning involving policy, institutional and technological innovations. This paper highlights the great potential of horticultural crops in alleviating food shortage and malnutrition in Africa, constraints, and the need to include nutrition education on agricultural research agendas. To compete in the export markets African countries need to produce horticultural crops or processed products that meet the export market standards, including specifications in importing countries, timely delivery, ample steady supply, grading, packaging, contracts or agreements to build trust, and good quality of product at arrival in the export market. The export marketing constraints and challenges, including poor communication system, lack of market infrastructure, agro-processing plants, marketing credit, proper market organization, proper pricing, uniform grading and standardization of weights and measures; inadequate and poor dissemination of market information, poor post harvest handling and low productivity. Opportunities for the horticultural industry in Africa, such as the development of indigenous vegetables, and orange-fleshed sweetpotatoes, and the use of plant biotechnology, are also discussed. © ISHS.