Mostrando ítems 1-20 de 362

    • Production model in the peruvian aquaculture industry

      Quiroz-Flores, Juan Carlos; Rios-Del-castillo, Piero; Guia-Espinoza, Renzo (Universidad del Zulia, 2022-01-01)
      This research seeks to validate a production model to improve the production processes of rainbow trout farming in the aquaculture sector of the southern region of Peru. The approach of the production model was determined through the combination of methodologies such as Lean Manufacturing and Business Process Management to facilitate process control, inventory management and production planning. These methodologies were integrated from the review of the literature and the diagnosis made through the collection of primary information from neighboring producers within the department of Junín, in central Peru. The results show the success of the model through its implementation in the fish farms of Junín farmers and a simulation in the ARENA version 14.0 software, in this way optimal results were obtained that show a significant improvement in productivity. The results obtained after the implementation and simulation show an increase of 71.87% in productivity with respect to the initial state, in addition, the production cycle time is reduced by 16.67%. It is concluded that the proposed production model is successful and compatible to improve production processes in the aquaculture sector.
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    • Ancestral technological solutions and their application in current times

      Barbachán Ruales, Enrique Alejandro; Barbachán Villalobos, Miguel Alejandro; Cáceres Coral, Jorge; Ruiz Camus, Carol Nadiezhda; Casas Huamanta, Edwin Roi (University of Cienfuegos, Carlos Rafael Rodriguez, 2022-02-01)
      The present work aims to recognize and revalue the technological solutions that our ancestors applied in accordance with the environment in order to be applied in current times. Quantitative research, of a descriptive type with an ethnographic, technological method, applied to students, teachers and university graduates in the technological and engineering area. The sample is non-probabilistic through convenience sampling. Concluding that, effectively, our ancestors applied various technological solutions in accordance with their environment, among which we find, for the metallurgical mining aspect, the Huayras; in the treatment and planting of water las Amunas; in infrastructure, earthquake-resistant technologies using mesh bags or Shicras; in soil and water management, the waru warus, production in floodplain or riverside areas, agriculture in Amazonian Várzea soils, these technologies have application in current times, which would be profitable and convenient in an eco system. sustainable, only 22% of those surveyed have knowledge of these technologies, so it is necessary to teach them from basic education.
      Acceso abierto
    • Quality model for educational mobile apps based on SQuaRE and AHP

      Del Aguila, Pablo; Roque, Dante; Wong, Lenis (Springer Science and Business Media Deutschland GmbH, 2022-01-01)
      During the last decade, there has been an increase in the demand of mobile apps in different download platforms, like Google Play Store, Apple App Store and Amazon App Store. Because of this, different approaches related to mobile app quality have surged, which tend to focus on assessing the general quality of an app without focusing on a specific sector. Because of this reason, the motivation to develop a quality model for mobile apps for the educational sector arises, using the System and Software Quality Requirements and Evaluation (SQuaRE) guidelines and the Analytic Hierarchy Process (AHP) weighting technique; the latter was used to prioritize the quality attributes. A quality model has been obtained, which consists of 8 characteristics, 19 sub-characteristics and 30 metrics. In order to corroborate the proposed model, 4 research questions and 2 case studies related to 2 mobile apps have been established. The results proved that Google Classroom and Moodle have very similar scores in each assessed characteristic; in the case of Usability, there is a difference of 0.006 in favor of Moodle, for Portability, there is a difference of 0.150 in favor of Google Classroom, and for Security, regarding authentication rules and mechanisms, both apps obtained the same result.
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    • Enterprise architecture based on TOGAF for the aof educational institutions to e-learning using the DLPCA Methodology and Google Classroom

      Puntillo, Geraldine; Salazar, Alonso; Wong, Lenis (Springer Science and Business Media Deutschland GmbH, 2022-01-01)
      Given the current situation of online classes, it is necessary to implement a Business Architecture model in order to facilitate the adaptation of virtual teaching, since 97.4% of teachers give up the use of information systems for learning. In addition, up to 80% of students experience stress with this new modality of learning. Based on this context, we can identify the gap in the adaptation to the virtual class process as a latent problem. Therefore, a model composed of 3 stages (Analysis, design, and validation) is proposed. Stage 1 includes the analysis of components on which the model will be developed. Stage 2 describes the Open Group Architecture Framework (TOGAF) on which the model will be developed, and the Discover, Learn, Practice, Collaborate, and Assignment (DLPCA) e-learning Methodology as the basis of the business process to be proposed. Finally, in stage 3, the model was validated in a private school in Lima with 70 students, 2 teachers, and 1 director, where it was shown that our proposal increased user satisfaction by 18.97%, positively increased adaptation to virtual classes by 28.50%, and also obtained a 75.34% acceptance of our proposal by the subjects of study, which shows the effectiveness of our solution to the problem.
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    • Concrete sustainable buildings using domestic wastewater treated

      Verde, Sharlys; Aranibar, Aderly; Rodriguez, Jose; Eyzaguirre, Carlos (Trans Tech Publications Ltd, 2022-01-01)
      During recent years, the rapid growth of the population in urban areas has promoted the development of housing, roads, shopping centres and industries; having increased the consumption of tap water in the concrete industry. A solution to this problem, is to use domestic wastewater treated, due to the large quantities produced and the need to include them within the life cycle of the water; thus bridging the gap of service in urban and rural areas. The present research seeks to use the domestic wastewater treated in the production of concrete for construction; the results show slightly for the slump, initial setting time and splitting tensile increase, and that the resistance to compression and flexural is decreased.
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    • Influence of cement on concrete mix designs through sustainability indicators

      Gil, Lucero; Ruiz, Sheyla; Rodriguez, José; Vise, Juan (Trans Tech Publications Ltd, 2022-01-01)
      Internationally, the most widely used concrete mix design methods are the American Concrete Institute, Department of Environment, Indian Standard, Fineness Modulus and Walker. These methods propose the dosage of materials from tables and graphs developed from multiple experiments and generalize the designs to achieve optimum strength, durability, and quality performance. However, sustainability does not contemplate the design, especially cement, which is responsible for CO2 emissions and the cost of concrete. The study analyzed the procedure and dosage of five methods for a 20 MPa strength concrete mix in the laboratory and applied them to beams and columns in a multi-family building using sustainability indicators. The results indicate that the IS method uses water efficiently, is more economical, and requires less cement, while the ACI method generates a positive environmental and social impact due to the efficient consumption of materials.
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    • Efficient selection and evaluation of suppliers: a model for a microenterprise in the textile sector in Lima, Peru

      Cornejo-Cabanillas, Katya; Muñoz-Corales, Ninuzka Alondra; Elias-Giordano, Cinthia; Torres-Sifuentes, Carlos; Raymundo, Carlos (IEEE Computer Society, 2022-02)
      n Peru, the textile sector has experienced a decline in recent years and generates a significant number of direct and indirect jobs. One of the main causes of this is a destabilized supply chain, and supplier management is one of the main obstacles. To improve the fulfillment of the orders of the companies with their final customers, be competitive and to establish a balance and good agreements with their suppliers in a situation of uncertainty, with this study a supplier management model has been developed. It is based on Supply Chain Reference Model and Supplier Potential Matrix which give the framework to evaluate those suppliers who can help to streamline the supply chain. The success of the study is reflected on savings and time reduction for the procurement process.
      Acceso abierto
    • Recurrent neural networks for deception detection in videos

      Rodriguez-Meza, Bryan; Vargas-Lopez-Lavalle, Renzo; Ugarte, Willy (Springer Science and Business Media Deutschland GmbH, 2022-01-01)
      Deception detection has always been of subject of interest. After all, determining if a person is telling the truth or not could be detrimental in many real-world cases. Current methods to discern deceptions require expensive equipment that need specialists to read and interpret them. In this article, we carry out an exhaustive comparison between 9 different facial landmark recognition based recurrent deep learning models trained on a recent man-made database used to determine lies, comparing them by accuracy and AUC. We also propose two new metrics that represent the validity of each prediction. The results of a 5-fold cross validation show that out of all the tested models, the Stacked GRU neural model has the highest AUC of.9853 and the highest accuracy of 93.69% between the trained models. Then, a comparison is done between other machine and deep learning methods and our proposed Stacked GRU architecture where the latter surpasses them in the AUC metric. These results indicate that we are not that far away from a future where deception detection could be accessible throughout computers or smart devices.
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    • Measuring agri-food supply chain performance: insights from the Peruvian kiwicha industry

      Ramos, Edgar; Coles, Phillip S.; Chavez, Melissa; Hazen, Benjamin (Emerald Group Holdings Ltd., 2022-04-26)
      Purpose: Agri-food firms face many challenges when assessing and managing their performance. The purpose of this research is to determine important factors for an integrated agri-food supply chain performance measurement system. Design/methodology/approach: This research uses the Peruvian kiwicha supply chain as a meaningful context to examine critical factors affecting agri-food supply chain performance. The research uses interpretative structural modelling (ISM) with fuzzy MICMAC methods to suggest a hierarchical performance measurement model. Findings: The resulting kiwicha supply chain performance management model provides insights for managers and academic theory regarding managing competing priorities within the agri-food supply chain. Originality/value: The model developed in this research has been validated by cooperative kiwicha associations based in Puno, Peru, and further refined by experts. Moreover, the results obtained through ISM and fuzzy MICMAC methods could help decision-makers from any agri-food supply chain focus on achieving high operational performance by integrating key performance measurement factors.
      Acceso abierto
    • Comparing the impact of internet of things and cloud computing on organisational behavior: a survey

      García-Tadeo, Diego A.; Reddy Peram, Dattatreya; Suresh Kumar, K.; Vives, Luis; Sharma, Trishu; Manoharan, Geetha (Elsevier Ltd, 2022-01-01)
      Cloud computing is about delivery of different computing services involving databases, analytics, software, networking with the use of internet to enhance innovation, incorporate flexibility in resources and broaden profitability. However, Internet of Things (IoT) is an essential system for interrelating computer devices, digital machines, people and others which are offered with unique identifiers where data can be transferred with human involvement and wireless network. 42% of organisations in UK use cloud computing. The problem with cloud computing revolves around security and privacy issues as data is stored by a third party from inside or outside of the organisation leading to broken authentication, compromising of credentials and others. The use of IoT is vulnerable as it provides connectivity to devices, machines and people therefore, it needs to contain more storage that is made from cloud facilities. Survey has been conducted where primary quantitative method has been considered to obtain data from 101 managers of the organisation that has adopted cloud computing and IoT. However, 8 close-ended questions have been asked to 101 managers. Positivism philosophy has been used to make quantifiable observations along with descriptive design and others. The results and discussion will analyse responses of the respondents after conducting statistical analysis. However, research has been revolving around making a comparison between using cloud computing and IoT along with analysing organisational behaviour.
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    • Stability analysis using the finite element method of a slope in the Virgen de Fátima Sector of the San Juan de Lurigancho district of Lima, Peru

      Carrizales, N.; Rodriguez, R.; Vasquez, J. (Springer Science and Business Media Deutschland GmbH, 2022-01-01)
      The geometric alteration of slopes is a reality that can be observed in several districts of the Peruvian capital. The construction of houses, roads, and other infrastructure can produce some slope instability and cause tragic events. Thus, a stability analysis was carried out for a slope located in the San Juan de Lurigancho district, specifically in the Virgen de Fátima sector. Therefore, for the present investigation, two models were made with the help of Phase2 software to identify the resistance reduction factors (SFR), which is a finite element-based program. To start the analysis, possible failures were identified, demonstrating that the slope does not present any possibility of failure. For the first model, we worked with a dip of 30° and identified an SFR = 19.26 for static conditions and an SFR = 9.66 for pseudo-static conditions. For the second model, we worked with a dip of 55°, this change in slope geometry shows a possible wedge failure, according to the kinematic analysis. Also, an SFR = 0.89 was identified for static conditions and an SFR = 0.48 for pseudo-static conditions. The results show very considerable changes and are due to the geometry of the slope, the presence of discontinuities, and the participation of seismic forces.
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    • Measuring the impact of pedestrian flow on vehicle delays for a proposed DLT intersection with two displaced left turns in an urban commercial area

      Acuña, B. E.; Amaya, L. C.; Sanchez, A. M. (Springer Science and Business Media Deutschland GmbH, 2022-01-01)
      This study evaluates the impact of pedestrian flow through vehicular delays in a proposed DLT intersection located in an urban area with a high vehicular and pedestrian traffic volume. In addition, it evaluates the pedestrian–vehicle conflict points, the effect on the other accesses after the implementation of the displaced left turns, and the consequences of reorganizing pedestrian flow. Three scenarios are evaluated through microsimulation; the existing one, which is a conventional cross-shaped intersection; a proposed DLT intersection with two displaced left turns on adjacent accesses; and a third one, similar to the last one, but with the inclusion of a pedestrian underpass. Results indicate that a proposed conventional DLT increases the vehicle delays of the intersection by 6.0% compared to the existing condition, mainly due to the high volume of pedestrians and the conflicts it generates. However, with the inclusion of a pedestrian underpass, vehicle delays are reduced significantly by up to 34.0%.
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    • Influence of PET fibers on compressive strength, water absorption percentage and density of adobe

      Ordoñez, Denys; Noa, Melisa; Carrera, Elsa (Trans Tech Publications Ltd, 2022-01-01)
      Adobe is a building material that has been used since ancient times, but is not as widely used as clay bricks or concrete for housing construction. In addition, it uses a construction technique that has been passed down and improved from generation to generation. In view of this, the present work aims to improve the properties of adobe by using PET bottle fibers in its composition. A mechanical test and two physical tests were carried out for adobe with 0% (standard adobe), 2%, 4% and 6% PET fibers, where it was observed that the adobe with 6% PET fibers obtained the best results, since it increased the compressive strength of the adobe by 19%, reduced the absorption percentage by 12% and finally reduced the density by 16.4%. Therefore, the addition of PET fibers in adobe is recommended, as it contributes to improve its mechanical and physical properties. Additionally, it reduces pollution in streets, rivers, parks, etc. because it promotes the recycling of PET bottles.
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    • Comparative seismic behavior the retrofit of 60year old hospital between CFRP materials and concrete walls by nonlinear static analysis

      Criales, Xiomara; Altamirano, Anilú; Huaco, Guillermo (Trans Tech Publications Ltd, 2022-01-01)
      The Casimiro Ulloa Hospital is a confined masonry structure more than 60 years old that does not satisfy the requirements of the Peruvian seismic code E.030 and it is located at high seismic zone. Therefore, this hospital is susceptible to collapse and becomes an essential deficient structure. Therefore, the present study is based on a comparative analysis between reinforced concrete wall and CFRP sheets through the nonlinear Push Over method in order to obtain which is the best reinforcement in structural capacity. The reinforcement with eight L-shaped concrete walls of 15 cm thick located at the corners of the structure, increased the strength of the hospital by 115% in longitudinal direction (Axis X) and 108% in transversal direction (Axis Y), and also increased the ductility by 3% and 117% in the directions respectively. The other reinforcement was carried out with CFRP sheets and anchors. The sheets were designed with a width of 9 inches and were placed in an X-shape in the masonry load-bearing walls and the anchors were implemented in the corners of the laminate walls in order to ensure adequate load transfer between the sheets and the surface. This reinforcement increased the strength of the structure by 345% in axis X and 150% in axis Y and increased the ductility by 59% in longitudinal direction and 331% in transversal direction.
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    • 3D semi-analytical solution of hygro-thermo-mechanical multilayered doubly-curved shells

      Monge, J. C.; Mantari, J. L.; Arciniega, R. A. (Elsevier Ltd, 2022-04-01)
      In this paper, a three-dimensional bending solution of doubly-curved shells subjected to mechanical, thermal and hygrothermal load is studied. Through-the-thickness temperature of the shell is modeled by Fourier's heat conduction equation. Fick's moisture diffusion law equation is used to determine the hygro-thermal profile through-the-thickness. The partial differential equations are solved by using the Navier closed form summations which are valid only for shells with constant radii of curvature among the midsurface and with simply supported boundary conditions on its shell's edges. The shell governing equations are solved by discretizing the thickness profile via Legendre's grid distribution and by using the Differential Quadrature Method (DQM). The Layerwise capabilities of the method is guaranteed by imposing the inter-laminar continuity of out-of-the-plane stresses, displacements, temperature and hygrothermal load thickness profile. The zero-stress condition for the transverse shear stresses is imposed due to the fact that no mechanical loads are applied in those directions. Results for cylindrical, spherical panels and rectangular plates are presented. Comparisons are made with Layerwise and three-dimensional solutions available in literature. The results have strong accuracy and a benchmark problem is delivered.
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    • Analysis of human physical vulnerability using static equilibrium techniques of a Hazard flood for the determination of unsafe areas in the city of Catacaos - Piura, Peru

      Carrizales, J. A.; Rodas, M. C.; Castillo, L. F. (IOP Publishing Ltd, 2022-01-06)
      Heavy rains and El Nio phenomenon are recurring natural phenomena at a national level. These can cause floods due to the overflowing of rivers, which, when close to cities, can cause both human and material losses. The district of Catacaos, located in the city of Piura, was the one with the highest number of injuries due to the flood caused by El Nio phenomenon in 2017. This phenomenon causes a large amounts of rainfalls due to the presence of abnormally warm waters along the northern coast of Peru [1]. It is for this reason that the need arose to carry out an analysis of the physical vulnerability due to instability of people through static equilibrium, in said district, in order to present maps of unsafe areas in the face of this phenomenon. In this investigation, flood hazard maps are generated simulating the one presented in 2017, using 2D hydraulic modeling. For the generation of vulnerability curves, the instability analysis is performed by moment and drag force. Finally, maps with unsafe areas are made using ArcGis software. Where the results obtained indicate that 29.37% of the city was flooded. Likewise, the vulnerability maps generated show us that women and men over 18 years of age in the city of Catacaos would be vulnerable to dragging and overturning in the face of floods in 16.54% and 13.21%, respectively, of the total studied area. This information will be useful for the development of future evacuation plans during floods, carried out by national entities. © Published under licence by IOP Publishing Ltd.
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    • Influence of the types of grass of green roofs for the design of thermal comfort in buildings

      Rodríguez, José; Vilela, Karina (Polskie Towarzystwo Inzynierii Ekologicznej (PTIE), 2022-01-01)
      The main objective of the research was to study the effect of the Stenotaphrum secundatum and Zoysia japonica grasses on the higher and lower environment temperature and lower relative humidity; the secondary objective was to compare whether the Stenotaphrum secundatum grass has a greater impact on the environment parameters of comfort than the Zoysia japonica species. Six materials were used for the extensive green roof, each one forming a layer of the system, which were placed on the concrete slab and in an upward direction, including: PVC geomembrane, Polyester asphalt carpet, Pumice stone, Planar geodren, Prepared soil with guano, compost, muss, and Substrate. In order to make measurements of the higher and lower ambient temperature, a digital thermometer and lower relative humidity meter was used. Stenotaphrum secundatum and Zoysia japonica were used as grass species, as they were the most representative of the grasses used in extensive green roofs. The experimentation was carried out for 2 months from September to October of 2021, having built 3 modules of 1000x600mm roofs, including 1module of the concrete roof with ceramic covering and 2 modules of extensive green roof with two types of grass: Stenotaphrum secundatum and Zoysia japonica. The readings of the environment temperature and relative humidity of the higher and lower part were taken in six points of each module to have a greater number of representative measurements. The watering of the 2 green roof modules with grass was carried out twice a week, applying 5L of water per module. The results indicate that the Zoysia japonica grass is the one that presents a better behavior before the higher ambient temperature and that the Stenotaphrum secundatum grass behaves better before the lower ambient temperature and lower relative humidity. The conclusions indicate that the Stenotaphrum secundatum grass behaves better temperature and relative humidity; the two grass types exhibit different behavior.
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    • Vulnerability curves for masonry buildings affected by hyperconcentrated flows as natural disaster risk management tools for the quantification of material damage

      Jara, A.; Quispe, T. Y.; Castillo, L. F. (IOP Publishing Ltd, 2022-01-06)
      The damage assessment caused by floods, earthquakes, hurricanes among others phenomenons in the world are analyzed with methodologies such as "Vulnerability curves". In Peru, disasters caused by hyperconcentrated flows are alarming due to a climatic variability such as the "El Nio Costero"phenomenon. Therefore, this research has developed vulnerability curves for 1 and 2-story confined masonry buildings in Urb. San Idelfonso, Ica - Peru; linking the variables: flow depth, associated with the event produced by heavy rains at the top of the "Quebrada Cansas"caused by the "El Nio Costero"phenomenon in 2017, and the percentage of the damage based on the methodology of the United States Army Corps of Engineers (USACE), whose formula is the repair value and total building value. The monetary amounts and items of the buildings are obtained from the RM 415-2017-VIVIENDA of the Ministry of Housing, Construction and Sanitation of Peru. The process consisted of hydrological modeling in HEC-HMS, hydraulic modeling in FLO-2D, damage percentage estimate and vulnerability curves production. Finally, the vulnerability curves for hyperconcentrated flows were contrasted with similar studies regarding curves for flooding and debris flow. The results of the investigation showed that the "El Nio Costero"phenomenon in 2017 had an economic impact of at least 1.3 million soles in Urb. San Idelfonso. In addition, at least 24 buildings had a complete damage and 21 buildings an extensive damage.
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    • Intelligent gravitational search random forest algorithm for fake news detection

      Natarajan, Rathika; Mehbodniya, Abolfazl; Rane, Kantilal Pitambar; Jindal, Sonika; Hasan, Mohammed Faez; Vives, Luis; Bhatt, Abhishek (World Scientific, 2022-01-01)
      Online social media has made the process of disseminating news so quick that people have shifted their way of accessing news from traditional journalism and press to online social media sources. The rapid rotation of news on social media makes it challenging to evaluate its reliability. Fake news not only erodes public trust but also subverts their opinions. An intelligent automated system is required to detect fake news as there is a tenuous difference between fake and real news. This paper proposes an intelligent gravitational search random forest (IGSRF) algorithm to be employed to detect fake news. The IGSRF algorithm amalgamates the Intelligent Gravitational Search Algorithm (IGSA) and the Random Forest (RF) algorithm. The IGSA is an improved intelligent variant of the classical gravitational search algorithm (GSA) that adds information about the best and worst gravitational mass agents in order to retain the exploitation ability of agents at later iterations and thus avoid the trapping of the classical GSA in local optimum. In the proposed IGSRF algorithm, all the intelligent mass agents determine the solution by generating decision trees (DT) with a random subset of attributes following the hypothesis of random forest. The mass agents generate the collection of solutions from solution space using random proportional rules. The comprehensive prediction to decide the class of news (fake or real) is determined by all the agents following the attributes of random forest. The performance of the proposed algorithm is determined for the FakeNewsNet dataset, which has sub-categories of BuzzFeed and PolitiFact news categories. To analyze the effectiveness of the proposed algorithm, the results are also evaluated with decision tree and random forest algorithms. The proposed IGSRF algorithm has attained superlative results compared to the DT, RF and state-of-the-art techniques.
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    • Evaluation of the Effectiveness of Flexible Debris Flow Barriers for Control of Huaycos Using Satellite Images and GIS, in the Basin of Rímac River, Perú

      Pareja Dominguez, Marco Antonio; Pascual Figueroa, Henry Douglas; Silva Dávila, Marisa Rosana (Springer Science and Business Media Deutschland GmbH, 2022-01-01)
      Recurrent economic and human losses occur in populated areas caused by the debris flow, known in Peru as “huayco” and for which there is little information. To determine the effectiveness of debris flow barriers installed in 2016 in three high-risk creeks with slopes ranging from 29 to 35%, it was analyzed satellite images with the Geographical Information System (GIS). For that, it is necessary to obtain the volumes of both soil erosion in the upper basin transported by the debris flow and the retained solids by the barriers. Topographic, geological, geomorphological, and hydrological characteristics were evaluated, as well as the evolution of the population in the dejection cone. It was no possible to obtain results for all the destructive events because there are no cartographies, and the available satellite images do not have enough temporal or spatial resolution or present cloudiness greater than 20%. The field investigations after the ENSO 2017 occurrence made it possible to verify that the debris flow barriers allowed to avoid the loss of human life and material damage. The field measured volumes of the solids retained by the barriers and the previously estimated volumes of erosion were compared, and retention efficiency of 80–90% was obtained. It recommends continuing with this research because it is necessary to know debris flow characteristics for analyzing the convenience and technical requirements for the implementation of retention barriers in other dangerous streams that are difficult to access.
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