• 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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    • 5S hybrid management model for increasing productivity in a textile company in Lima

      Neyra, Juanirene; Muñoz, José; Eyzaguirre, Juan; Raymundo, Carlos (Springer Verlag, 2020-01-01)
      In general, lean strategies in the textile sector are applied in production to improve productivity, reduce production time, and reduce errors, among other aspects. However, there are also documented studies, which are not common in the literature that uses these strategies to improve storage operations. This study shows the implementation of the Lean 5S Hybrid tool in the warehouse of a textile company based in Lima. The objective of the implementation was to improve productivity in the warehouse, as there were high response times when searching for materials, which reduced production time, warehouse redistribution, better using available space, and being able to strategically locate main materials. The results revealed an increase in warehouse productivity 3.95 times the initial one, an Inventory Record Accuracy of 98.17%, a decrease in the requirement search time by 66.12% (from 25 to 8 min), and stock rotation of 6.22 times.
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    • 6TOC model for small wood furniture companies to increase machining productivity in Villa El Salvador industrial cluster

      Gutierrez, Leonel; Laredo, Jesus; Sotelo, Fernando; Raymundo, Carlos (Springer Verlag, 2020-01-01)
      This research article focuses on the application of the main engineering tools in the wood furniture manufacturing sector. It uses as an information source furniture companies of the industrial park of Villa El Salvador. Its objective is to implement 6TOC methodology based on LEAN philosophy, Six Sigma and restrictions theory, focusing on improvements to the bottleneck. Defines the product design as an ideal input for the planning and development of activities. Start to know the work environment: stations and functions, machines and tools, plant layout and ergonomics in order to increase productivity. Application of tools level operations for planning, control and execution of production. Resulted in the GDP in the year 2017 increased by 2.2%. However, the manufacturing sector of goods decreased by 5.5%, that is, it impairs GDP growth, since the wood and furniture industry, which had an aggregate gross manufacturing value of −19.9%.
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    • A biometric method based on the matching of dilated and skeletonized IR images of the veins map of the dorsum of the hand

      Universidad Peruana de Ciencias Aplicadas (UPC) (IEEE, 2015-06-02)
      This work proposes a biometric identification system that works together with a palm vein reader sensor and a hand-clenching support, designed to perform the capture the back of the hand. Several processing steps were performed: extraction of the region of interest, binarization, dilation, noise filtering, skeletonization, as well as extraction and verification of patterns based on the measurment of coincidence of vertical and horizontal displacements of skeletonized and dilated images. The proposed method achieved the following results: processing time post capture of 1.8 seconds, FRR of 0.47% and FAR of 0,00%, with a referential database of 50 people from a total of 1500 random captures.
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    • A Novel Steganography Technique for SDTV-H.264/AVC Encoded Video

      Di Laura, Christian; Pajuelo, Diego; Kemper, Guillermo (Hindawi Publishing Corporation, 2016-04)
      Today, eavesdropping is becoming a common issue in the rapidly growing digital network and has foreseen the need for secret communication channels embedded in digital media. In this paper, a novel steganography technique designed for Standard Definition Digital Television (SDTV) H.264/AVC encoded video sequences is presented. The algorithm introduced here makes use of the compression properties of the Context Adaptive Variable Length Coding (CAVLC) entropy encoder to achieve a low complexity and real-time inserting method. The chosen scheme hides the private message directly in the H.264/AVC bit stream by modifying the AC frequency quantized residual luminance coefficients of intrapredicted I-frames. In order to avoid error propagation in adjacent blocks, an interlaced embedding strategy is applied. Likewise, the steganography technique proposed allows self-detection of the hidden message at the target destination. The code source was implemented by mixing MATLAB 2010 b and Java development environments. Finally, experimental results have been assessed through objective and subjective quality measures and reveal that less visible artifacts are produced with the technique proposed by reaching PSNR values above 40.0 dB and an embedding bit rate average per secret communication channel of 425 bits/sec. This exemplifies that steganography is affordable in digital television.
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    • Adaptation of the raise borer elaboration method to a short ore pass by evaluating its efficiency

      Huaynate, Andree; Jara, Juan; Raymundo, Carlos (Springer Science and Business Media Deutschland GmbH, 2019-01-01)
      The recent climate change has forced people to live in extreme conditions, either excessive heat or cold, implying that they must adapt to survive in these situations. However, there are people who, because of their geographical condition and lack of resources, lack the means and tools to combat these climate changes. The context of this study is provided in a rural town located in the Arequipa region (Peru), whose inhabitants have to fight against frosts of up to −20 °C in an area without electricity. A viable solution to this problem is found through the design and implementation of a heating system using geothermal and photovoltaic energy, which are resources found in the area, according to a report of the Ministry of Energy and Mines. This study analyzes and researches the geographical and meteorological conditions of the region, for validating, through theory and simulations, whether the proposed system can supply the thermal energy required to maintain the indoor temperature at a minimum of 15 °C under extreme conditions. The system is designed after analyzing the best technological options and techniques currently available in the context studied for its ultimate financing and establishing guidelines and indicators for monitoring results.
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    • Additional results on integrals of beam eigenfunctions

      Morales, César A; Facultad de Ingeniería, Universidad Peruana de Ciencias Aplicadas, Lima, Perú (SAGE Publications Ltd, 2018-03-14)
      New simplest expression beam mode integrals are presented, including further simplifications and corrections of previous results; this type of integrals appear in computational methods in structural dynamics and vibrations of diverse structures and machines, and in aircraft dynamics methods.
    • Admissible height and urban density of buildings for the Prospective Management of Seismic Risk in residential areas

      Herrera, Fabiola; Mamani, Flaby; Arana, Victor (Institute of Electrical and Electronics Engineers Inc., 2020-09-30)
      This research proposes limit values of height and population density of buildings for a Prospective Management of Seismic Risk in residential areas. The analysis of an efficient evacuation of buildings to the street or refuge area was carried out, evaluating human behavior with models based on the agent, the influence of buildings and the urban parameters of the city with three-dimensional models (BIM) for a severe seismic scenario. The present article establishes that the maximum permissible height of buildings projected in a residential avenue is directly related to the width of the available refuge zone to guarantee the correct evacuation of said zone during a severe seismic event. In addition, an evaluation of a real existing scenario is made in a section of a residential avenue.
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    • Adoption of snowball sampling technique with distance boundaries to assess the productivity issue faced by micro and small cocoa producers in Cusco

      Jalca, Angie; Lopez, Marco; Sotelo, Fernando; Raymundo, Carlos (Springer Verlag, 2020-01-01)
      The food supply chain has gained impulse over the past few years induced by the rising global demand for food; therefore, much emphasis is placed upon examining this class of supply chains. It also faces constant production, storage, and distribution challenges, wherein the key link for proper operation is the farmer, who engages in the agricultural sector, heavily impacted by low crop productivity, which interfer with economic development at a national level. Consequently, it is important to assess those farmers who belong to micro and small enterprises in the agricultural sector. Due to the characteristics of the population, a nonprobability sampling technique was used to assess micro and small cocoa producers in La Convención Province, Cusco, Peru. To such end, a snowball sampling model with distance boundaries was adopted because the population is unknown and hard to reach.
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    • Adsorption of N,N-dimethylamine from aqueous solutions by a metal organic framework, MOF – 235

      Beltrán-Suito, Rodrigo; Pinedo-Flores, Angela; Bravo-Hualpa, Fabiola; Ramos-Muñoz, Jorge; Sun-Kou, María del Rosario; msun@pucp.edu.pe (Taylor and Francis Inc., 2018)
      Water-resistant MOF-235 was used to adsorb N,N-dimethylamine (DMA) from aqueous solutions. It was synthesized from terephthalic acid and FeCl3.6H2O under air-free conditions and characterized by its crystalline structure, functional groups and temperature resistance. The kinetic data results were best adjusted to the pseudo-second order model (R2>0.963). The best-fit isotherm, Langmuir model, suggested the adsorption of DMA is localized on homogenously distributed active sites on the surface. This fit was confirmed by the value of β = 1 on the Redlich-Peterson model. Our study suggests that the manipulation of novel materials such as MOF-235 promises new avenues for water treatment solutions. Schematic structure of MOF-235 and its application as adsorbent.
    • Agile and sustainable methods to implement 6S in textile manufacturing MSEs

      Quea, Camila; Sánchez, Karla; Mauricio, David; Raymundo, Carlos; Dominguez, Francisco (International Institute of Informatics and Systemics, IIIS, 2019-01-01)
      No presente resumen.
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    • Agile Inventory Management Model Under a Digital Transformation Approach for Stockout Reduction in Chemical Industry’s MSE

      Garamendi-Colos, Virginia; Cano-Lazarte, Mercedes; Mamani-Macedo, Nestor; Raymundo, Carlos; Dominguez, Francisco (Springer, 2020-01-01)
      Through digital transformation, company processes that are, or could be, conducted manually are reduced; moreover, human tasks are automated when software-based processes are established. This paper analyzes the adoption of a digital transformation tool to manage inventory through the application of agile models, such as Just-In-Time, and the use of Enterprise Resource Planning (ERP), employing the Deming cycle method, as several unclear empiric processes exist for managing inventory and purchases. It also upholds that as defined processes are established and the companies exert higher control over inventory turnover and outflows, they could apply methods, such as demand forecasting, to avoid stockout, supply shortage, and inventory loss.
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    • Agile Logistics Management Model to Reduce Service Times and Improve Processes Using Lean Service Methodology in Companies in the Electrical Sector

      Palomino, Viviana Barriga; Raffo, Sotelo; Fernando, Juan Luis (Institute of Electrical and Electronics Engineers Inc., 2021-03-01)
      In recent years, according to Osinergmin, the production of electrical energy has increased up to 2.4%. This sector represents 1.5% of GDP and encompasses more than 6.6 million users, so its consumption continues at a growth rate for the country's development. This growth depends on the response time that companies today provide users; many of them operate their logistics management manually and traditionally, which leads to delays in service and dissatisfaction of both the external and internal clients. Likewise, companies in the sector, by working traditionally, do not use technology as a point of competitiveness within the market, since 60% of companies use software for their operations. To do this, an agile logistics management model is proposed that will consist of reducing purchase order attention time by 50% and improving internal processes and procedures under the Lean Service methodology. It will start by identifying the main problem and the expected objectives, then the Lean Service, Business Process Management and Agile Logistics tools will be executed, which will help to reestablish new processes and procedures.
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    • Algorithm for Detection of Raising Eyebrows and Jaw Clenching Artifacts in EEG Signals Using Neurosky Mindwave Headset

      Vélez, Luis; Kemper, Guillermo (2021-01-01)
      The present work proposes an algorithm to detect and identify the artifact signals produced by the concrete gestural actions of jaw clench and eyebrows raising in the electroencephalography (EEG) signal. Artifacts are signals that manifest in the EEG signal but do not come from the brain but from other sources such as flickering, electrical noise, muscle movements, breathing, and heartbeat. The proposed algorithm makes use of concepts and knowledge in the field of signal processing, such as signal energy, zero crossings, and block processing, to correctly classify the aforementioned artifact signals. The algorithm showed a 90% detection accuracy when evaluated in independent ten-second registers in which the gestural events of interest were induced, then the samples were processed, and the detection was performed. The detection and identification of these devices can be used as commands in a brain–computer interface (BCI) of various applications, such as games, control systems of some type of hardware of special benefit for disabled people, such as a chair wheel, a robot or mechanical arm, a computer pointer control interface, an Internet of things (IoT) control or some communication system.
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    • Algorithm Oriented to the Detection of the Level of Blood Filling in Venipuncture Tubes Based on Digital Image Processing

      Castillo, Jorge; Apfata, Nelson; Kemper, Guillermo (2021-01-01)
      This article proposes an algorithm oriented to the detection of the level of blood filling in patients, with detection capacity in millimeters. The objective of the software is to detect the amount of blood stored into the venipuncture tube and avoid coagulation problems due to excess fluid. It also aims to avoid blood levels below that required, depending on the type of analysis to be performed. The algorithm acquires images from a camera positioned in a rectangular structure located within an enclosure, which has its own internal lighting to ensure adequate segmentation of the pixels of the region of interest. The algorithm consists of an image improvement stage based on gamma correction, followed by a segmentation stage of the area of ​​pixels of interest, which is based on thresholding by HSI model, in addition to filtering to accentuate the contrast between the level of filling and staining, and as a penultimate stage, the location of the filling level due to changes in the vertical tonality of the image. Finally, the level of blood contained in the tube is obtained from the detection of the number of pixels that make up the vertical dimension of the tube filling. This number of pixels is then converted to physical dimensions expressed in millimeters. The validation results show an average percentage error of 0.96% by the proposed algorithm.
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    • Analysis of conflict points between pedestrians at BRT stations to prevent the spread of respiratory diseases

      Escalante, Katherine Atapauccar; Hugo Ramirez Ruiz, Bryan; Silvera, Manuel; Campos, Fernando (Institute of Electrical and Electronics Engineers Inc., 2020-09-30)
      Bus Rapid Transit (BRT) is a bus-based public transport system that increase the effectiveness of public transportation through dedicated lanes with busways and independent stations. However, the low capacity at the stations and the high demand of the system increases the respiratory diseases risk caused by the interaction between pedestrians. This article proposes to make the main access point an entrance only and the access point at the opposite end of the platform an exit only, allowing one-way walking paths. This research is focused on the reduction of conflict points between pedestrians generated by walking flows in opposite directions. A BRT station located in the city of Lima was used as a case study for the investigation. It was identified for the peak hour that the area with the highest pedestrian interaction occurs in the station platform and boarding areas. The efficiency of the proposal is validated by using the Viswalk software. The results obtained show that the conflict points decreased by 68.5% and the pedestrian density by 45%. From that perspective, the pedestrian flows were optimized, and the risk of respiratory diseases was reduced.
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    • Analysis of high plasticity clayey soil improvement at subgrade level through Portland cement added to decrease volumetric change

      Castro, M. (Institute of Physics Publishing, 2020-02-28)
      This research includes the potential for resistance and the expansion that the soil presents, this evaluation was carried out through CBR tests. The soil cement technique was used to improve the physical and mechanical characteristics; this process consists in mixing the material with Portland cement type I. That combination forms soil cement 10%, 15% y 20%, which present an increase of the CBR (max: 138.7% and min: 91.9%) achieving a type of extraordinary subgrade to resist the structure of the pavement and a reduction of 7.18% in the expansion of the samples.
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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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    • Analysis of seismic bidirectionality on response of reinforced concrete structures with irregularities of l-shaped plan and soft story

      Sobrado, V. H.; Yaranga, R.; Orihuela, J. D. (IOP Publishing Ltd, 2020-09-22)
      The seismic design of buildings is usually performed using one-way analysis for each of main axes independently. However, seismic events have fairly random behaviour and impose bidirectional solicitations on structures. In this work, the study of the response in structures subjects to earthquake loads with irregularity of l-shaped plan and soft story is carried out. For this, the linear time-story analysis (LTHA) of these has been carried out imposing seismic solicitations in two orthogonal directions. Thus, the structural response with incidence angle variations of 10 is obtained and compared with the response derived from the unidirectional analysis. Variations of up to 50% and 72% are obtained for model structures with l-shaped plan and soft story respectively.
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    • Analysis of the influence of the characteristics of the environment on the time of pedestrian transhipment in a multimodal transport using the social force model

      Asenjo, Christian; Tocas, Frank; Silvera, Manuel; Campos, Fernando (Institute of Electrical and Electronics Engineers Inc., 2020-09-30)
      The Highway Capacity Manual (HCM-2010) indicates in Volume III (Chapter 17) how the characteristics of the environment can represent obstacles that influence the determination of the average pedestrian space. However, the HCM does not specifically analyse in detail how these obstacles affect specifically the path, speed and average walking time of pedestrian. This article performs a comparative analysis between two microsimulations models where it is evidence how by not considering the characteristics of the fixed and mobile environment, the transhipment time and the speed of people are modified. As a case study, the obstacles present in the environment during the transhipment carried out by users in an integrated multimodal transport system in the city of Lima are identified. The comparative analysis between both cases shows the influence of the characteristics of the environment of the transhipment and variation in the average speed of the pedestrians. The proposed study methodology is calibrated and validated by microsimulations in Vissim Software. The comparative analysis reflects an increase in the transhipment time of 19.4% and a decrease in the average speed of the pedestrians by 14.8 %, reflecting in the microsimulation model values near to the real behaviour of pedestrians.
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