bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of the Influence of Curing Laquers on the Durability on Concrete Products
Authors: Hubáček Adam
Published: August 2020

Currently, especially for concrete pavements, new methods of finishing facing layers using special methods and technologies are beginning to appear. The added value of these elements is ensured by special coatings as well as by the choice of the final surface-hardening method. Such treated vibropressed concrete elements are more resistant to external climatic effects, they have an extreme low-maintenance treatment of the facing surface and their water absorption is significantly lower, significantly increasing the service life of these concrete elements. The aim of the article is to summarise the existing knowledge of vibropressed concrete products, the surfaces of which are treated using these technologies. Emphasis is placed on the description and effectiveness of the use of individual methods, the principles of surface hardening and possible further surface treatments for concrete products with the aim of achieving greater durability. Some properties of these vibropressed elements will be examined, including surface resistance to water and chemical defrosting agents, water absorption of concrete, surface roughness, slip resistance and the reduction of the risk of lime efflorescence formation on the product surface.
Numerical Analysis of Temperature Distribution throughout a Concrete Slab during Fire Using a Web-Based Solver
Authors: Holan Jakub , Štefan Radek
Published: August 2020

The problem of heat transfer in solid materials can be described by the well known transient heat transfer equation. However, as the problem is strongly non-linear, the solution to this equation generally cannot be determined directly. Various numerical approaches have been proposed and employed by various authors for solving the problem.However, most of the available numerical solvers are limitedly available as they are often not free to use, they have to be installed, and they are too complex.This paper presents a new web-based solver for the problem of heat transfer over the thickness of a concrete slab during fire developed by the authors.The computational algorithm is based on the finite difference method and implemented using JavaScript.A graphical user interface for the input of user-defined parameters and for the interpretation of results is created using HTML.The paper also briefly presents the theory behind the computational algorithm.Moreover, examples of various problems solved by the web-based solver are presented in the paper.A brief parametric study of the effect of initial density of the material on the temperature distribution in the slab during fire is also presented. From the presented figures and examples, it can be readily seen that the newly developed web-based solver for the assessment of temperature distribution over a slab thickness during fire is user-friendly, easy to use, highly accessible, fast, and intuitive.
Basis for Design of Bearings in New the Generation of Eurocodes
Authors: Marková Jana , Holicky Milan , Jung Karel , Sýkora Miroslav
Published: August 2020

A new generation of Eurocodes for structural design is currently being prepared within the Technical Committee CEN/TC 250. The revised Eurocode EN 1990 will be supplemented by the new Annex F for the basis of design of bridge bearings. Harmonised European provisions are still missing with recommended procedures for determination of basis of design and actions on bearings, taking into account various types of uncertainties. In particular, problems can occur where it is necessary to replace bearings at existing bridges according to the new procedures of Eurocodes which can lead to the design of a bigger size of new bearings despite the existing bearings served well for many years. The developed amendment of National Annex to EN 1990 for the basis of structural design should refine the design procedures. The submitted paper describes inconsistencies and main principles of the changes focusing on thermal actions.
Safety of the Models for Assessment of Punching Resistance of Flat Slabs with Openings Adjacent to the Columns
Authors: Kormosova Ľudmila , Halvonik Jaroslav , Majtánová Lucia
Published: August 2020

The paper deals with the quality of the current EC2 (2004) model for predicting punching capacity of flat slabs without transverse reinforcement, supported by elongated columns and weakened by two openings placed adjacent to the column. The ratio column’s section height/effective depth of a slab was six. The reference punching capacities were obtained from non-linear analyses carried out on the flat slab fragments. Five different arrangements of the openings were tested with three models that take into account an effect of the openings on the punching resistance. Based on the investigation performed, it was observed that the length 3d of the effective part of a column perimeter along the column height h with the ratio h/d > 3 is very conservative. The whole control perimeter contributed to the punching capacity for all slab fragments tested. Current design model EC2 (2004) is safe in the case of predicting the punching capacity of flat slabs with openings adjacent to the columns if the standard method of reduction of the control perimeter lengths due to openings is used. The most consistent results provided method that is based on the Augustin's proposal for reduction of the control perimeter length.
Large-Size Jointless Concrete Slab-on-Grade with Combined Prestressing
Authors: Tur Andrei V.
Published: August 2020

In the international and national practice of design, a different type of slab on the various types of grade are becoming increasingly common. For such structural elements, shrinkage and temperature influences in combination with low tensile stress, mainly in early age, leads to the risk of cracking in reinforced concrete structures, and as result, a reduction of its durability. The present article describes some of the possible ways of usage of the post-tensioned flat slabs and the rational design procedures to provide their structural reliability. The theoretical background of the punching resistance checking, in the case when the piles support the foundation post-tensioned slabs, presented. For ground floor slabs, an iterative method is given for determining design compression pre-stresses distribution in slab sections, taking into account the restrained effect created by the friction shear stresses in contact between the slab and the base. Besides, the article presents some practical implementations of the post-tensioned slabs as an artificial base in the presence of weak soils and as a large-size ground floor (slab-on-grade) without any joints.
Effect of Fire Model Parameter Variability on Determination of Fire Resistance of Concrete Structural Members
Authors: Benýšek Martin , Štefan Radek , Procházka Jaroslav
Published: August 2020

The paper is focused on the fire model parameter variability and its effect on the determination of fire resistance of concrete structural members.For the modelling of fire, the parametric temperature-time curve given in EN 1991-1-2 is used.First part of the paper is aimed on the fire model parameter variability in general.First, fire model parameter ranges are described and their combinations are created using two common sampling methods -- Monte Carlo and Latin Hypercubes.Then, the combinations are analysed, unreasonable combinations are identified, and viable combinations are illustrated.Moreover, the characteristics of the temperature-time curves obtained using the parameter combinations are discussed. Namely, we focus on the temperature evolution, duration of fire, andthe maximum temperature reached.In the second part of the paper, an illustrative example is presented.The example is focused on the analysis of the fire resistance of a concrete slab panel. The panel is placed in a fire compartment with given fire model parameter ranges. In the example, the variability of the fire model parameters is captured using the Latin Hypercubes sampling method.The thermal analysis of the slab panel as well as the subsequent mechanical analysis are both conducted by using numerical methods described in our previous work. The calculations are performed in MATLAB environment.Finally, the obtained results are presented and discussed.It is shown that the Latin Hypercube sampling can be used as an effective tool for the investigation of the effect of fire model parameter variability on the fire resistance.
High Performance Fine Grained Concrete with Content of Pumice
Authors: Bilek Vlastimil , Pešata Michal , Prochazka Lukáš
Published: August 2020

Pumice is a volcanic rock that consists of a highly vesicular rough textured volcanic glass. It is very porous and shows a high absorption - it can contain a lot of water. Thanks to its low volume density, it is sometimes used as a light natural aggregate, especially for some small elements such as chimney blocks. The paper is focused on the development of concretes and mortars for these purposes. The optimum content of pumice was specified from the point of view of mechanical properties. Special attention was paid to absorbed water - it can be a source of self-curing of concrete.
Approaches to Determine Material Model of Fibre Reinforced Concrete
Authors: Tipka Martin , Vaskova Jitka
Published: August 2020

The paper deals with possible ways of defining the material model of fibre reinforced concrete as a material for structural design. The material model is a tool that can be used to describe response of material to the applied load. It usually includes several different parameters: strengths, ultimate deflections, deformation modules, fracture energy, etc. The paper deals with the problematic phases of tests that are necessary to create a material model, but which may not always provide relevant data. Due to the nature of the material (a fibre reinforced composite with a relatively brittle matrix), it is necessary to analyse separately the behaviour of the material before and after cracks when creating the material model.
Reconstruction Effectiveness of Locally Supported Flat Slabs to Increase in Shear Resistance
Authors: Bolešová Mária , Gajdošová Katarína , Čuhák Marek
Published: August 2020

The most used horizontal load-bearing systems in concrete buildings are flat slabs. The effective and economic reconstruction of a locally supported flat slab of an existing building creates a complex task. Shear stress arises near the column and it becomes critical in design with increasing slab slenderness and requires a more detailed calculation. Increasing in the shear resistance of the flat slab can be achieved in various ways. Each method brings different effectiveness, advantages and disadvantages. The most widely used methods of the reconstruction are the increase in the size of the column (therein increasing the control perimeter for displaying the shear stress), the increase in the thickness of the flat slab or reinforcing the slab with shear reinforcement. Bolts and screw anchors (using different mounting angles) can be used as shear reinforcement. Each mentioned reconstruction method should be subjected to numerical calculations and verification of its efficiency. The parametric study presented in this paper is focused on the reconstruction techniques and their verification according to various numerical models. The results from Eurocode 2, fib Model Code 2010 and the new generation of Eurocode 2 are compared to show the differences between them. The aim of this paper is to bring a demonstration of the reconstruction methods that will increase in the shear resistance of the locally supported flat slabs and trying to choose the most effective one.
Influence of Washing of Crushed Aggregate on Mechanical Properties of High-Performance Concrete Containing Supplementary Cementitious Materials
Authors: Fladr Josef , Bily Petr , Trtík Tomáš , Chylík Roman , Hrbek Vladimír
Published: August 2020

The paper compares macromechanical and micromechanical properties of high-performance concrete containing supplementary cementitious materials and basalt aggregate. The aggregate was either a common unprocessed crushed basalt aggregate or crushed basalt aggregate the coarse fractions (4/8 and 8/16 mm) of which were washed by water and dried before use. The observed macro-mechanical properties were compressive strength, tensile strength, elastic modulus and depth of penetration of water under pressure; the paper is focused on the first observed property, which is the basic material characteristic. On the microscale, the thickness of the interfacial transition zone (ITZ) was determined by nanoindentation. The positive influence of supplementary cementitious materials and aggregate washing on compressive strength was confirmed and the correlation between macromechanical and micromechanical characteristics was proved.
Service Life of Concrete Structures
Authors: Holicky Milan , Kolisko Jiří
Published: August 2020

The concept of service life of structures is included in international standards ISO (under the term Design Working Life), in the European document EN 1990 (Design Service Life) and in the upcoming document CEN for assessment of existing structures - Technical Specification TS (Remaining Working Life). The mentioned documents contain mainly material-independent provisions for the design and assessment of all types of structures and for any category of actions. The submitted paper includes the definition of service life (performance time) tser, which is extended for any concrete structure, considering the resistance of a structure R(t) and the effect of action S(t). Both the aggregate variables R(t) and S(t) are usually random variables significantly dependent on time t. Due to the random variability of the variables R(t) and S(t), the service life tser, needs to be related to the probability that the performance of the structure is weakened or completely eliminated. Basically, serviceability limit states (SLS) and ultimate limit states (ULS) should be considered. In the case of concrete structures another limit state corresponding to the beginning of a specific degradation process (corrosion of reinforcement), denoted tinit, may be important. In specific cases of buildings and bridges a functional (moral) service life may be taken into account. The paper includes also a practical example of assessing the remaining working life of a concrete structure.
Prestressing Steel Ropes - Corrosion Impact on its Properties
Authors: Kolisko Jiří , Vacek Vítězslav , Pokorný Petr , Kostelecká Michaela
Published: August 2020

Steel reinforcement made of refined maraging steel in the form of wires and tendons has been for a long time used commonly for reinforcement of prestressed concrete structures. Defects on some of them and unfortunately even accidents of some cases of bridge objects, mainly recently published by media, related to corrosion of prestressed reinforcement awoke interest of both professional and wide non-professional public related to its durability. This issue also opens up a question of durability and liability of prestressed structures. In majority of existing prestressed structures the anticorrosion protection of reinforcement was traditionally secured mainly by alkalinity of the environment, i.e. concreting and/or grouting of prestressed elements in ducts. The abstract presents information related mainly to mechanical characteristics of corrosion-affected prestressed elements.
Quantification of Microstructural Changes in Limestone Cement Paste Stored in Sulfate Environment at Low Temperature
Authors: Sotiriadis Konstantinos , Hlobil Michal , Machová Dita , Mácová Petra , Viani Alberto , Vopálenský Michal
Published: August 2020

Portland-limestone cement paste specimens were stored in magnesium sulfate solution at 5°C for 6 months; the occurring microstructural changes have been monitored on a monthly basis. Extent of deterioration was quantitatively assessed with different techniques. The X-ray micro-computed tomography was employed to describe non-invasively the pore structure and extend of deterioration. X-ray powder diffraction and infrared spectroscopy were used to characterize the phase changes occurred in the course of the sulfate attack. Compressive strength tests reflected the effect of the process on mechanical performance. The results indicate the rapid degradation of the system, owing, mainly, to crack formation, expansion, and finally loss of cohesion between the deteriorated parts of the specimens and the sound cement matrix, as a consequence of the formation of new phases. The progress of an irregular deterioration front was observed. The presence of complex phases (thaumasite, ettringite) was proved, however, the deteriorated parts of the specimens mostly consisted of gypsum.
Determination of Concrete Resistance to Corrosive Effects of Water with Aggressive CO2 Using Model Mortars
Authors: Kocáb Dalibor , Terzijski Ivailo , Strnad Jiří , Ševčík Michal
Published: August 2020

The paper deals with an experimental determination of resistance of concrete to the corrosive effects of demineralised water with aggressive carbon dioxide. Three types of concrete were used for the experiment, one designated for reference, another one contained a crystallising admixture, and the third type contained admixtures and was designed to be very resistant. The actual tests were, however, not conducted directly on these concretes but on model mortars derived from those concretes. The paper provides reasons why the tests specimens were produced from the model mortars and not from the given concretes. The conclusion of this paper presents not only the results of the described experiment but also comparisons with the results of previously conducted and published tests.
Evaluation of Self-Healing in Concrete by Means of Analytical Techniques
Authors: Aspiotis Konstantinos , Sotiriadis Konstantinos , Kumpová Ivana , Mácová Petra , Badogiannis Efstratios , Tsivilis Sotirios
Published: August 2020

In the present work, the self-healing process in concrete was evaluated using analytical techniques. For this purpose, two concrete mixes of different composition (one used as control) were prepared with a water-to-binder ratio of 0.45. The self-healing process was triggered by the introduction in the concrete mix of a commercial expansive admixture (calcium sulfo-aluminate), two dicarboxylic acids, and sodium carbonate salt. After 28 days curing in water, the specimens were artificially cracked (crack width ≤ 900 μm) and then again water-cured for further 60 days until self-healing occurred. The progress of self-healing was investigated with a stereomicroscope at 40, 50, and 60 days, after cracking, to identify the quality and the degree of the healing. The efficiency of the self-healing process was also evaluated using micro-Raman spectroscopy and X-ray micro-computed tomography. Significant reduction in the crack width was observed as a result of a calcite filling, generated during the self-healing process. In some cases (crack width < 400 μm), the crack was completely healed. The experimental methodology used provided new insights into the evolution of the self-healing phenomenon in concrete.
Comparison of Resistance of Concrete for Sewage Pipes to Sulphate Corrosion Using Model Mortars
Authors: Kocáb Dalibor , Terzijski Ivailo , Strnad Jiří , Louda Pavel
Published: August 2020

This paper briefly discusses the basic theoretical findings about sulphate-induced corrosion of concrete and also the possibilities how to determine the degree of concrete resistance to such corrosion in the most effective way. The described experiment involves a twofold comparative test – monitoring of selected parameters of two model mortars stored in both the corrosive and the reference environments (water bath). During the test, these model mortars represent commonly used concrete for the manufacture of concrete sewer pipes. The article also explains why and how the mortars were designed and tested instead of concrete. The conclusion of the paper presents the results and their evaluation.
The Effect of Eccentricity of Concrete Specimen on Measured Value of Modulus of Elasticity
Authors: Chylík Roman , Trtík Tomáš , Fladr Josef , Vaskova Jitka
Published: August 2020

The measurement of the modulus of elasticity is a technologically demanding test and its correct implementation has a fundamental effect on the resulting measured value. The main influences that may affect the proper performance of the test include, for example, the shape and size of the test specimen, the method of obtaining the test specimen, the method of adjustment of contact area between specimen and hydraulic equipment, but also the eccentricity of the specimen in the test apparatus. The paper presents the results of an experiment focused on the influence of the eccentricity of the test specimen and the observance of standard measurement conditions. The standard determines the maximum strain difference on individual measuring sensors when the maximum test force is reached.
Fluctuación poblacional de Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) en el cultivo del sorgo del sur de Anzoátegui, Venezuela
Authors: Bertorelli María Virginia , Olivares Barlin Orlando
Published: August 2020

Este estudio tuvo como objetivo evaluar la fluctuación poblacional de Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) en etapa larval, en las diferentes etapas fenológicas del sorgo y su relación con el tipo de labranza, las condiciones climáticas, y distintos sistemas de uso del sorgo en el Fundo Las Tunas, municipio Simón Rodríguez, estado Anzoátegui, Venezuela. Para la evaluación se utilizaron cuatro sistemas de uso: S1 (Sorgo-Stylosanthes brasilianum-Brachiaria dictyoneura); S2 (Sorgo-Centrosema brasilianum-B. dyctioneura); S3 (Sorgo-B. dyctioneura); y S4 (Sorgo monocultivo) bajo dos tipos de labranza (liviana y profunda). La determinación de la fecha de ocurrencia de las etapas fenológicas del cultivo se realizó dos veces por semana durante todo el ciclo del cultivo. Los resultados del estudio revelaron que la fluctuación poblacional de S. frugiperda no se vio influenciada por el sistema de uso, pero sí por el tipo de labranza, se presentaron mayores valores de fluctuación población del insecto (>0.80 larvas por planta) con la labranza profunda. Se evidencia una estrecha relación entre estos factores de fluctuación poblacional del insecto, condiciones climáticas y los días después de la siembra; un mayor ataque de la plaga ocurrió en el periodo vegetativo cuando se presentaron bajos montos de precipitación diaria y altas temperaturas.
CRECIMIENTO Y DESARROLLO DE ZARZA NEGRA (Mimosa pigra L.) EN EL ESTE DE PUERTO RICO
Authors: Arocho José , Robles Wilfredo , Lugo-Torres María de L.
Published: August 2020

Resumen
Study on Pervious Concrete by Partial Replacement of Silica Fume and GGBS with Cement and Addition of Glass Fibers
Authors: Y Priyanka, V Venkatadurga Raju and V Bhargavi
Published: August 2020

Pervious Concrete for the pavements proves to be an effective and along- term solution for the universal
problem of abnormal decrease of ground water table. Pervious Concrete has a unique mix design and giving
special properties to the concrete which makes the concrete porous , allowing water from precipitation and
other sources to pass directly through , there by reducing run off volume and increasing ground water table.
Inorder to reduce the damage being caused to the environment by the use of cement , inpervious concrete ,
cement is replaced with pozzolanic materials such as GGBS , silica fume sand to increase strength and
durability , glass fibers in stipulated ratio are added to the concrete mixture. In this study ,the mix designs
such as M30 and PC30 are considered . The fine aggregate is replaced with coarseaggregate by different
ratios like 0% , 5% , 10% ,15%. by adding different pozzolanic matrals like GGBS, silicafume with glassfibers.
To find the effectiveness of the use of pozzolancic and glassfibes, compressive strength conducted. The
following Conclusions can be summarized by analyzing tests performed on PC specimens. A significant
reduction of workability. And A progressive addition in compressive strength by increasing the percentage of
fine aggregates and pozzolanic materials in mix. The conclusion of fine aggregate content in the specimen
increases the density and increase the pozzolanic materials addition. And addition of silica fume and GGBS
in the mixtures improve strength , compressive strength increases even after adding pozzolanic materials.
Due to increase of fine aggregate content. For all replacement levels of PC with other mixes goes on decreasing
in strength when compared with parent grade ofM30. While comparing with PC with Pozzolanic materials, For
7 days there is a drastic change for same replacement, and for 28 days itshowssimilar trend for 25%
pozzolanic concrete and goes on decreasing for strength for compressive strength. For all replacement levels
of PC with pozzolanic goes on decreasing in strength when compared with parent grade of M30. Compressive
strength slightly increased by adding glass fibers to the allmixes.
Moral y orden. La delincuencia y el castigo en los inicios de la modernidad en Ecuador
Authors: Goetschel Ana María
Published: August 2020

En este libro, largamente esperado, Ana María Goetschel ofrece una valiosa y original interpretación sobre las relaciones entre los complejos procesos de formación del Estado ecuatoriano, los proyectos modernizadores de las élites, y la producción y funcionamiento de aparatos carcelarios y de castigo que, vistos en esa perspectiva, dejan de tener una función meramente punitiva y pasan a cumplir un rol central en el ejercicio estatal de la violencia y el control sobre las poblaciones. Anclado en un sólido andamiaje teórico y una investigación de archivo exhaustiva, el libro de Goetschel contribuye también al mejor entendimiento de las ideologías de género, esas que modelaron el ejercicio del castigo, el funcionamiento –ambiguo y complejo– del Estado como un aparato civilizatorio y normalizador, y los mecanismos empleados por las poblaciones carcelarias para enfrentarse a sus circunstancias. Estamos frente a un libro honesto, comprometido y riguroso que habrá de generar debate y reflexión sobre el pasado pero también, y de manera urgente, sobre los desafíos y dilemas del presente.
Comentarios sobre la extinción de la personalidad jurídica de las mancomunidades y la transmisión de deuda a las entidades sucesoras.
Authors: Gallardo Gutiérrez Joaquín
Published: August 2020

El proceso de disolución y liquidación en el que desde 2012 se encuentra inmersa la mancomunidad de Municipios del Bajo Guadalquivir (en adelante MMBG) ha dado lugar a una gran problemática, no sólo desde el punto de vista de la gestión, pues el proceso ha sido especialmente complejo, sino también desde el punto de vista jurídico.
Crónica de la incipiente actividad parlamentaria de la XI Legislatura
Authors: Vázquez Alonso Víctor J.
Published: August 2020

A pesar de que nos encontramos en un momento casi fundacional del mandato parlamentario, puede que se hayan  producido determinadas actuaciones que merecen ser objeto de atención en esta crónica, aun cuando se encuentren en la mayoría de los casos en fase de tramitación.
Notas de Jurisprudencia.- Tribunal Constitucional
Authors: Escribano López Francisco
Published: August 2020

SUMARIO:I. Constitución. A. Fuerza normativa. B. Interpretación. II. Derechos y libertades. A. Derechos fundamentales y libertades públicas. B. Derechos y deberes de los ciudadanos. C. Principios rectores de la política social y económica. D. Garantía y suspensión de estos derechos. III. Principios jurídicos básicos. IV. Instituciones del Estado. A. La Corona. B. Las Cortes Generales. C. El tribunal Constitucional. D. La Administración Pública. E. El Poder Judicial. V. Fuentes. VI. Organización Territorial del Estado. A. Comunidades Autónomas. A.1. Autonomía. B.2. Competencias. B. B. Corporaciones Locales. A.1. Autonomía B.2. Competencias.VII. Economía y Hacienda. A. Principios generales. B. Presupuestos. C. Organización territorial.D. Tribunal de Cuentas.
Reseña de las Disposiciones Generales de la Junta de Andalucía
Authors: Reina Emilio Guichot
Published: August 2020

Se recogen y comentan las disposiciones generales más relevantes de la Junta de Andalucía publicadas en el BOJA en el período de diciembre de 2018 a marzo de 2019.
EDUCATION FOR SUSTAINABILITY DEVELOPMENT VIA SCHOOL GARDEN
Authors: Papadopoulou Aikaterini , Kazana Athina , Armakolas Stefanos
Published: August 2020

The garden can be viewed as an imitation of nature in an urban setting. In past times, many educators aware of the importance of nature in the education process were avid supporters of the school garden. Many studies that examined the influence of the school garden in the education process have shown that it offers multiple benefits to the students, one of which is that it furthers experiential learning. Students involved in gardening improve their overall academic performance and increases their interest in learning. It also seems to have positive effects on their overall behavior and on their emotional and social health. In the results of studies, we can also see the students who participated in gardening showed remarkable improvement in their overall physical health, and that they often adopted better nutritional habits. Finally, the school garden can serve as a portal for the students and for the school in general, to introduce them to environmental education and to sustainability in both theory and practice.

 

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ANÁLISIS SOCIOECONÓMICO DEL TURISMO EN EL CANTÓN ESMERALDAS, ECUADOR
Authors: Bustos Gámez Mercedes , Oyarvide Ibarra Romina Tanagra
Published: August 2020

SOCIOECONOMIC ANALYSIS OF TOURISM IN THE CANTÓN ESMERALDAS, ECUADORRESUMENEl presente trabajo basado en la investigación participativa, se ha involucrado a los principales protagonistas del turismo, como son los microempresarios, dueños y operarios de los locales turísticos en los balnearios del cantón Esmeraldas. En la presente investigación se ha determinado y analizado, los principales factores que inciden en el desenvolvimiento de las diferentes actividades que ha realizado dicho segmento económico, en especial en el área financiera crediticia, a la vez se han formulado y sugerido estrategias las cuales están enfocadas principalmente en la promoción de los lugares turísticos del cantón Esmeraldas, con lo cual se espera mejorar el nivel de calidad de los bienes y servicios de los dueños de los locales turísticos y por ende el desarrollo social y económico de la provincia verde, orgullo de los ecuatorianos.PALABRAS CLAVE: Microempresarios; crédito; turismo; promoción; calidad; servicio.ABSTRACTThe present work based on participatory research, has involved the main protagonists of tourism, such as microentrepreneurs, owners and operators of tourist facilities in the spas of the Esmeraldas canton. In the present investigation has been determined and analyzed, the main factors that affect the development of the different activities that has made this economic segment, especially in the credit financial area, while they have formulated and suggested strategies which are focused mainly in the promotion of the tourist places of the Esmeraldas canton, with which it is hoped to improve the level of quality of the goods and services of the owners of the tourist premises and therefore the social and economic development of the green province, pride of the EcuadoriansKEYWORDS: Microentrepreneurs; credit; tourism; promotion; quality; service.
EVALUACIÓN DEL PLAN DE DESARROLLO Y ORDENAMIENTO TERRITORIAL DE LA PARROQUIA RURAL MEMBRILLAL, JIPIJAPA, MANABÍ
Authors: Fuentes Figueroa Tomás Robert , Pillasagua Salvatierra Colón Rafael , Santistevan Villacreses Karina Lourdes
Published: August 2020

EVALUATION OF THE DEVELOPMENT AND TERRITORIAL PLAN OF THE RURAL PARISH MEMBRILLAL, JIPIJAPA, MANABÍRESUMENLos Planes de Desarrollo y Ordenamiento Territorial Parroquial (PDOT’s), son instrumentos de planificación, elaborados de forma participativa con la sociedad civil y actores territoriales. La parroquia Membrillal, está ubicada al noroeste del cantón Jipijapa, su clima es Tropical Seco, Sabana de Costa. La principal actividad económica es la agricultura, destacándose el cultivo de maíz (Zea mays L.) que lo producen en el periodo invernal aprovechando las lluvias. El objetivo de la investigación fue evaluar el sistema económico del PDOT’s en la parroquia Membrillal, Jipijapa, Manabí, Ecuador, enfatizando en aquellos que inciden en la seguridad alimentaria local. Se realizaron visitas periódicas y entrevistas a la población local. Se obtuvo que de 14 proyectos establecidos, solo el 35% obtuvo la meta establecida. Los proyectos ejecutados por el Gobierno Autónomo Descentralizado (GAD) han generado fuentes de trabajo para los miembros de la comunidad. Se consideró evaluar anualmente el PDOT para verificar los logros en función a la conservación del medio ambiente y los recursos naturales. Se recomienda socializar los resultados de la evaluación con la comunidad de tal forma que permitan delinear estrategias a favor del desarrollo local.  PALABRAS CLAVE: Desarrollo local; planes de ordenamiento; Membrillal, instrumentos de planificación.ABSTRACTThe Plans of Development and Parochial Territorial Organization (PDOT's), are planning instruments, elaborated in a participative way with the civil society and territorial actors. The Membrillal parish, is located northwest of the canton Jipijapa, its climate is Tropical Dry, Sabana de Costa. The main economic activity is the agriculture, standing out the cultivation of corn (Zea mays L.) that produce it in the winter period taking advantage of the rains. The objective of the research was to evaluate the economic system of the PDOT's in the parishes of Membrillal, Jipijapa, Manabí, Ecuador, emphasizing those that affect local food security. Periodic visits and interviews were made to the local population. It was obtained that of 14 established projects, only 35% achieved the established goal. The projects executed by the Autonomous Decentralized Government (GAD) have generated sources of work for the members of the community. It was considered to evaluate the PDOT annually to verify the achievements in terms of the conservation of the environment and natural resources. It is recommended to socialize the results of the evaluation with the community in such a way that they allow delineating strategies in favor of local development.KEYWORDS: Local development; ordering plans; Membrillal; planning instruments.
EVALUACION DE LA DINAMICA POBLACIONAL DE RHYNCHOPHORUS PALMARUM EN PALMA AFRICANA CON CUATRO TIPOS DE ATRAYENTES AZANZA MARTINEZ DERIAN ANDRES
Authors: Castro Landin Alfredo Lesvel , Merchán García William , Valverde Lucio Alfredo , Castro Piguave Carlos , Narvaez Campana Washington
Published: August 2020

La investigación evaluación de la dinámica poblacional del picudo de la palma (Rhynchophorus palmarum) en palma africana con cuatro tipos de atrayentes, tuvo como objetivos determinar la dinámica poblacional del picudo de la palma africana y evaluar el uso de cuatro tipos de atrayentes para el control de adultos del picudo. La metodología permitió utilizar un diseño experimental completamente aleatorizado y la variable evaluada fue  número de insectos adultos capturados por trampa cada siete días. Los resultados permiten concluir que la dinámica poblacional del picudo en palma africana indica que la mayor captura se obtuvo el 6 de julio con 383 capturas de insectos adultos y con tendencia a la baja hasta la evaluación cinco que fue efectuada el 3 de agosto donde se capturaron 239 insectos adultos; pero posteriormente en la siguiente evaluación se obtuvo un incremento de captura de insectos, lo que indica que es muy variada la fluctuación poblacional del picudo; además que el uso de cuatro tipos de atrayentes para el control de adultos del picudo, indica que la mayor captura en las siete evaluaciones efectuadas se presentó donde se utilizó las trampas con feromonas y ubicadas cada 300 metros de distancia con capturas ubicadas por trampa entre 18,00 y 28,75 insectos adultos capturadas cada 7 días.Palabras claves: etología, trampas, monitoreo, capturaSUMMARYThe research evaluation of the population dynamics of the palm weevil (Rhynchophorus palmarum) in African palm with three types of attractants, had as objectives to determine the population dynamics of the palm weevil and to evaluate the use of three types of attractants for the control of weevil adults. The methodology allowed us to use a completely randomized experimental design and the variable evaluated was the number of adult insects captured pro trap every seven days. The results allow us to conclude that the population dynamics of the palm weevil in African palm indicates that the highest catch was obtained on July 6 with 383 adult insect captures and with a downward trend until the five evaluation that was made on August 3 where they were captured. 239 adult insects; but later in the following evaluation an increase of insect capture was obtained, which indicates that the population fluctuation of the weevil is very varied; In addition, the use of three types of attractants for adult control of the weevil indicates that the largest catch in the seven evaluations carried out was where pheromone traps were used and located every 300 meters away with catches located by trap between 18,00 and 28.75 adult insects captured every 7 days.Keywords: ethology, traps, monitoring, capture
IMPACTO EN EL APRENDIZAJE DE LAS MATEMÁTICAS UTILIZANDO LA COMPUTADORA
Authors: Maldonado Zuñiga Kirenia , Vera Velázquez Raquel , Fienco Salca Miguel Alfredo , Lima Pisco Robards , Vigoa Escobebo Yisell
Published: August 2020

La investigación aporta el impacto que tiene la computación como medio de enseñanza en las clases de matemática,  los estudiantes se motiva y se concentran con mayor facilidad al utilizar las actividades didácticas interactivas computacionales, creadas en el programa Jclic. Son varias las dificultades que presentaron los estudiantes en las clases de matemáticas, la falta de motivación, de concentración, poco interés e indisposición por los comentarios de que la asignatura era difícil,   lo que dificulto el trabajo de los docentes. El objetivo de esta investigación es realizar medios de enseñanzas computacionales para que a los estudiantes y docentes se les haga más factible las clases de matemáticas. La utilización de varios métodos y técnicas en la investigación, determinaron la importancia de utilizar las actividades didácticas, para estimular el interés y la motivación de los estudiantes. Las entrevistas y encuestas aplicadas a estudiantes  y docentes de  la Universidad, permitieron el diseño de las actividades respondiendo a las necesidades de los estudiantes. Los resultados alcanzados en la  investigación se determinaron con la  validación de los cuestionarios, lo cual permitió identificar y conocer el grado y la falta de motivación por parte de los estudiantes y el gusto e interés por utilizar las computadoras en sus clases. Los resultados lograron cambios significativos que se produjeron al utilizar las actividades didácticas interactivas en las clases de matemáticas, mejorando notablemente la habilidad de resolver problemas matemáticos, su motivación e interés aumento hacia la asignatura matemática. El conocimiento y la participación de los estudiantes aumento favorablemente.
VIVENCIAS ACADÉMICAS DE LOS ESTUDIANTES DE I SEMESTRE MATUTINO DE TECNOLOGÍAS DE LA INFORMACIÓN-UNESUM
Authors: Lucio Villacreses Luis Fernando , Castillo Merino Miriam Adriana , Álava Cruzatty José Efraín , Lima Pisco Robards Javier , Vigoa Escobedo Yisell
Published: August 2020

Con la finalidad de conocer las vivencias académicas de 74 estudiantes que cursan en horario matutino el primer semestre de la Carrera de Tecnologías de la Información y Comunicaciones de la Universidad Estatal del Sur de Manabí, se recurrió a la experiencia desarrollada en Colombia por la Universidad de Bogotá, donde se aplicó un cuestionario que permite conocer de los estudiantes: El relacionamiento personal e interpersonal que mantienen; su adaptación vocacional respecto a la carrera elegida; las competencias y hábitos de trabajo que  mantiene dentro y fuera de la institución; y por último define el interés que tiene el estudiante hacia la institución donde estudia. Una vez aplicado el instrumento de medición, se pudo conocer que el 70,70% de los estudiantes gustan de la Universidad Estatal del Sur de Manabí, en contraste con el 29,30% que unas veces están de acuerdo y otras veces no, en pertenecer a la institución, en este mismo contexto, el 39,10% conoce los servicios que presta la universidad, mientras el 48,80% algunas veces dice conocerlos y otras no. Respecto a la ubicación física de la carrera, el 58,50% gusta del sector donde está situada. Todo lo expuesto, confluye en que el 63,50% de los estudiantes se plantee terminar la carrera que iniciaron y de este dato el 39,10% piensa que la universidad posee una buena infraestructura. Finalmente, se debe señalar que este indicador se puede incrementar favorablemente si las áreas correspondientes realizan el mantenimiento y equipamiento continuo a todas las dependencias de la institución.
EL MANEJO DE DESECHOS SÓLIDOS EN LAS INSTITUCIONES EDUCATIVAS
Authors: Pincay Franco Graciela Celeste , Bravo Muñoz Juber Roderich , Alvarez Luna Anaysa , Guerra Castro Flor Isdalba , Luna Baez Adis Anicia
Published: August 2020

El manejo y disposición de residuos sólidos en el mundo constituye un gran problema y es grave en las ciudades de los países en desarrollo y de este fenómeno social no se excluyen las instituciones educativas, es indispensable que los estudiantes se actualicen sobre este tema tan actual. Esta investigación tiene como objetivo evaluar las actividades relacionadas con el manejo de desechos sólidos de los estudiantes para mejorar el cuidado del medio ambiente en las instituciones docentes, es un estudio cualitativo, que utiliza la metodología exploratoria, de campo y bibliográfica, a través de métodos teóricos como: el análisis-síntesis, la abstracción, el histórico lógico para estudiar cómo evolucionó este proceso, además los empíricos como: entrevistas, encuestas, observaciones, revisión de documentos a directivos, docentes, estudiantes y padres, para constatar las insuficiencias que se presenta con respecto a la sistematización del manejo de desechos sólidos en la institución. Se diseñó una propuesta de actividades para mejorar el manejo de desechos sólidos y el cuidado del medio ambiente, orientada a fomentar la comprensión de la problemática y sus consecuencias en la salud de los estudiantes y su impacto negativo en el medio ambiente.
MAPAS CONCEPTUALES QUE APORTAN AL PROCESO DE ENSEÑANZA - APRENDIZAJE
Authors: Lucio Villacreses Luis Fernando , Castro Landin Alfredo Lesvel , Lima Pisco Robards Javier , Regalado Vásquez Mayra Fabiola
Published: August 2020

El presente artículo hace referencia inicial al método sugerido por Joseph D. Novak quien en el año 1972 desarrolló una herramienta a la que denominó mapas conceptuales, y al método creado en el año 2011 por Álvarez Marañón quien desarrolló siete pasos para la creación de un mapa conceptural. En este contexto, basado en la experiencia de 63 estudiantes que cursaron entre Mayo – Septiembre de 2019 el segundo nivel de Ingenieria en Tecnologías de la Información en la Universidad Estatal del Sur de Manabí, se realizó un analisis cualitativo y cuantitativo de los criterios y aspectos utilizados en el desarrollo de un mapa conceptual. Este proceso permitió por una parte, evidenciar que los estudiantes no tenian una guia metodológica definida, por ende se simplificaba el trabajo buscando en la internet mapas ya realizados y los estudiantes que realizaban un mapa conceptual incluian baja calidad y cantidad de información. Por otra parte, se pudo concertar tres procesos vitales a seguir: 1.- Búsqueda y análisis de información de fuentes confiables, que se sustenta con gráficos, fórmulas y ejercicios; 2.- Bosquejo de un diseño original que enlaza la información y/o contenidos seleccionados; 3.- Estructurar, organizar y elaborar el mapa conceptual de manera que contenga una aceptable cantidad y calidad de información, que incluye una exhaustiva revisión ortográfica y fuentes consultadas. Finalmente, el uso de esta técnica influenció en el aprendizaje significativo de las asignaturas de Algebra Lineal y Física, lográndose que el 95,24% es decir 60 estudiantes sean promovidos al nivel inmediato
USO DE ÁCIDOS ORGÁNICOS PARA MEJORAR LOS PARÁMETROS ZOOTÉCNICOS Y LA CALIDAD DE LA CARCASA DE POLLOS DE ENGORDE
Authors: Quijije Quiroz Karen Pilar , Borroto Leal Omelio E. , Quijije Quiroz Hilda Brigitte
Published: August 2020

El presente trabajo sobre el uso de ácidos orgánicos para mejorar los parámetros productivos zootécnicos y la calidad de la carcasa de los pollos de engorde se desarrolló en el sitio Andil zona rural del Cantón Jipijapa a 4,0 km aproximadamente por la vía Universitaria Noboa – Jipijapa, cuya finalidad fue establecer la dosis adecuada de ácidos orgánicos en la producción de pollos de engorde según el sexo (mortalidad, consumo de alimento, ganancia de peso y conversión alimenticia), evaluar la calidad de la carcasa de acuerdo a lesiones presentes en órganos respiratorio (pulmón y sacos aéreos) y digestivos (intestino y riñón), determinar mediante un análisis benefició costo la dosis rentable para la producción avícola. Dentro del desarrollo de la investigación se abordaron los diferentes métodos científicos tales como métodos teóricos: histórico-lógico, análisis–síntesis; método estadístico-matemático y el método bibliográfico. Los resultados permiten concluir que la mortalidad tuvo un porciento bajo con una muerte de 2 pollos en el T8, en cuanto a consumo de alimento el T6 M fue el más eficiente, ganancia de peso diferencia estadística en T4 M, demostró mayor eficiencia comparada al resto de tratamientos, la conversión alimenticia obtuvimos alta significancia estadística en el T3 H, con 1,92 siendo más eficiente la hembra.
INTEGRACIÓN DE SABERES EN LA PARROQUIA PEDRO PABLO GÓMEZ DEL CANTÓN JIPIJAPA
Authors: Vera Velázquez. Raquel , Maldonado Zúñiga Kirenia , Del Valle Holguín Wilfrido Javier , Valdés Tamayo Pedro Roberto
Published: August 2020

El suelo es un recurso finito, y los procesos naturales para su formación, desarrollo y restauración no ocurren a la misma velocidad a la que se degrada. En el presente artículo se definen y describen las principales propiedades físicas, químicas y biológicas del suelo, discutiendo su importancia y los valores típicos de los suelos agrícolas. Se hace una reflexión sobre la importancia de monitorear las propiedades del suelo y su manejo dirigido para evitar su degradación. Se analizan las relaciones interdisciplinarias entre las ciencias básicas para realizar el estudio del suelo agrícola de la parroquia rural la Pedro Pablo Gómez del cantón Jipijapa. Los métodos utilizados fueron exploratorio documental, a través del estudio e investigación bibliográfica, estadístico con la documentación de la parroquia y la experiencia de los pobladores de la parroquia. La gran presión sobre los suelos que la humanidad ejerce para satisfacer sus necesidades de alimento ha promovido su uso intensivo que, junto con las malas prácticas de manejo (tales como la labranza intensiva, monocultivo, aplicación indiscriminada de agroquímicos, entre otros), han provocado deterioro y degradación edáfica. El problema de fondo es el escaso entendimiento del ser humano sobre el suelo y sus propiedades por estas razones nos dimos a la tarea de investigar mediante los proyectos integradores de saberes las situaciones del suelo agrícola de las parroquias de la zona 4 provincia de Manabí para ayudar a la comunidad de Jipijapa en la capacitación y estudio del suelo para tener un mejor resultado en sus cosechas.