Tekhné

12

Authors: Ríos Bogart, Sonia Solórzano

Tibial torsion is a condition in which the tibia has a rotation along its axis. To calculate the worth of the rotation is necessary to make a series of studies and evaluations to determine right the angle, the problem become when these exam are performing, all of measures depends on the judgment and expertise of the doctor who will perform this, such key points as the axes of rotation can be assessed and determined by different methods may give different results. Because of this, is proposed to design a device to obtain in an easy, transparent and understandable way, the difference on the transverse plane of the angles between the axes of the knee and ankle, which indicates the worth of rotation. Was an analyzed different proposal of prototypes, choosing the one that better suits the needs that we want to cover. The prototype is compound by an ultrasonic sensors located at the ends of the axes of rotation in the ankle and. They provide distances that using an algorithm developed which allow know the angle of twist. To validate the prototype we worked with adult patients, whom clinical outcomes compared with existing current prototype results, showing that the device threw the expected results and work according to specifications.

18

Authors: Heriberto Echezuría

It was possible to demonstrate that the absolute value of the slope, m, of the line log(Su)-log(w) is intimately related to the plasticity of the soil, whereas, its position in the log(Su)-log(w) space is controlled by the amount of non-plastic fines in the soil. On the other hand, it was also demonstrated that for a given value of the Liquid Limit (LL) the value of, m, increases drastically as the Plasticity Index (PI) decreases, whereas, for a given PI the value of ,m, increases slowly as the LL increases. Consequently, it was possible to generate in the Plasticity Chart curves representatives to the locus of soils with identical value of, m. Furthermore, it was also established that the LL is related to the water content of the soil for a undrained remoulded shear strength of 1.5 kN/m2. All these facts allowed the formulation of an alternative method to classify plastic soils based on the locus of the value of, m, in the plasticity chart and the water content at a shear strength of 1.5 kN/m2 of the remoulded soil. It is worth mentioning that the soil classification obtained with thismethod is equivalent to that obtained with conventional ASTM methods to determine Atterberg Limits. Finally, it was demonstrated that the non-plastic fines content allows correlating the value of, m, with the liquefactionpotential of plastic soils.

22

Authors: Rafael Ernesto Prado Bellorin, Arnaldo Gutiérrez

The present research had the purpose of evaluate the structural sections C and Z manufactured in Venezuela, based on the North American Specification for the Design of Cold-Formed Steel Structural Members, AISI 2007. The investigation was intended to develop a calculation methodology that allowed determine geometrical properties, effective sections, nominal strength and design of the C and Z sections manufactured in the country. The technique used for data collection was the literature review and these were analyzed quantitatively. The intent of this study was to generate a theoretical basement- practical criteria established for the project (analysis and design) of this type of structural members.

12

Authors: Heriberto Echezuría

It was possible to store up to 49 m3 of viscous fluids in clays with different conditions. The injected fluid was stored in ellipsoidal cavities. The orientation of the ellipsoid axes can be defined according to injection needs. For the case of the 49 m3 bulb, it was oriented vertically with a major axis of 5,8 m and a horizontal axis of 4,0 m.It was also demonstrated experimentally that there exists a viscosity threshold above which the bulb can grow without limit, whereas below it only soil fracturing occurs. All the amounts of fluid injected were measured to compare and verify bulb sizes. Verification of the shape of the bulb was performed by tomographic techniques and SPT tests. It was detected that as the bulb grew it could cause failure of the ground above it up to the surface. This failure process was studied with the aid of anchor theories because it was controlled by the depth and size of the bulb. Induced pore pressures during injection indicate that flow during dissipation occursfrom the surrounding soil towards the bulb. The techniques developed during the process of cavity expansion can be applied to dispose materials in delicate areas for which transportation of those materials increase dramatically the operation costs. In addition, those techniques can also be applied to create lenses of soils with improved engineering properties in poor geotechnical profiles to fund with piles or to form columns of granular materials at low cost.

14

Authors: Katherin Jardim, César Itriago

Inventory management is the basis of all good planning for the flow of products. The objective of this study was to propose improvements to the inventory management of a secondary distribution center of a massive consume company, where the type of investigation is not experimental, with a workable project mode and descriptive level. In the work unit, formed by the Secondary Distribution Center (CEDIS), presents the description and analysis of the logistics activities and tasks related, using data recollecting techniques such as the direct non participative observation and non structured interviews techniques, obtaining as result the shipping and handling delay of products, the unknowledge of the capacity and failures of products in the warehouse, where improvement proposal was generated dividing the area in two: warehouse management and transportation of goods from the principal warehouse to the CEDIS. A primordial aspect for inventory management, is the need of having a warehouse with: adequate capacity, meets safety standards, defined operational areas and right storage of their products; for this reason was made the study of this aspects, defining the suitable reposition control for the inventory to prevent failure of customers orders. For the realization of the proposal were used several Industrial Engineering tools such as: Ishikawa diagrams, SWOT analysis (Strengths, Weaknesses, Opportunities y Threats), criticality analysis, entity relationship (E-R), ABC classification, average distance traveled, vertical space utilization, positioning labels creation, use of indicators and the creation of a program that facilitate the realization of purchase orders and maintenance of the inventory control.

23

Authors: Xavier Matheus, Rafael Torres

This paper proposes a calculation methodology for the development of highway bridge decks reinforced concrete beams in bridges located on main roads and secondary roads or agricultural penetration, using the AASHTO LRFD(1). During development of the subject, is appended to each equation the article stated in the rule. The separation between beams and the length of the flights of the slab, are selected for optimum conditions the design hypothesis is based on economic criteria. All beams of the bridges must be of equal resistance, therefore equal amount of reinforcing steel, as such, are selected separation between beams and flown, such that the difference between the maximum reinforcing steel (As major) and minimum (As minor) required for the different beams will not exceed 10%, ie. The final separation between beams is rounded to multiples of five centimeters, facilities construction, this condition implies not have values of ε = 0% (optimum condition). With the permanent loads and variable determining the shear stress and moment which are combi HTO LRFD (1), by the theory of limit state of fatigue resistant reinforcing steels obtained by cutting and flexion.

16

Authors: Rosseline Rodríguez, Leonid Tineo, Joel Rivas, Freddy Perozo

We present a tool for tuning control parameters of evolutionary programs (crossover probability, mutation probability, population size and generation gap). This tool was designed with a focus on meta-evolution: the top level, a genetic algorithm optimizes an evolutionary program in lower level. Given the amount of computation that this may mean is used master-slave parallel configuration, implemented transparently in a cluster with OpenMosix technology. The experimental results confirm the validity and generality of this tool.

18

Authors: Esmitt Ramirez, David Martínez, Rhadamés Carmona

Image segmentation is a relevant research field in image processing. Many advanced algorithms have been developed to separate an interest region of its background on color images (snakes, live-wire and others). However, the obtained results are not satisfactory in many cases. More accurate approaches are based on representing the image as a graph and separate it into two sub-graphs representing foreground and background. The GrabCut algorithm falls in this category. In this paper we present the theoretical background and a detailed implementation of the GrabCut algorithm with some improvements not presented in the original version. Particularly the N-Link, T-Link and min-cut calculations were modified. These changes improve the results on foreground and background edge pixels and also speed up the min-cut algorithm. Our implementation shows good results for the test images used.

21

Authors: Maria Alejandra Francis, Arnaldo Gutiérrez

This article is a summary of the Special Work “Adequacy of American Institute of Steel Construction (AISC) prequalified seismic connections to the steel structures practice in Venezuela” (14) presented at the UCAB on October 2011 as a requirement to achieve the degree of EXPERT IN STRUCTURAL ENGINEERING, which studies the evolution of the moment connections and the impact of their behavior after the earthquakes in California (Northridge, 1994) and Japan (Kobe, 1995) which caused extensive damages to steel structures fractured moment connections. It also presents the updates that have been developed internationally by the Federal Emergency Management Agency (FEMA) and the American Institute of Steel Construction (AISC); calculation procedures for moment connections, specially End Plate Moment Connections; application examples to validate the calculating procedures and compare the updates that have been published; design tables for shapes used in Venezuela and proposed upgrades Venezuela’s existing standards.

30

Authors: Jose Grases

This paper contains a recollection of events related to pathological conditions of structural systems as well as forensic type cases that have affected Venezuela since the last two centuries. Analysis of its origin contain lessons that along the last decades have been incorporated as preventive strategy to present design codes and specifications; some of them are still valid in order to reach integral preventive strategies. Collected events have been grouped according to its origin. A list of quoted references is given in order to open further windows of study. It is recommended to take uncertainties associated to external actions together with those related to expected structural response into consideration, in order to reach properly sustained quantifications of expected reliability to external hazards.

10

Authors: Luis Uribe

Microcomputer systems normally update data to nonvolatile memory (flash or EEPROM), or to Database Servers (both local or remote). This paper specially focuses on small, embedded processors, and presents a robust algorithm that prevents data losses and inconsistencies due to power failures, or similar program interruptions. It is centered on multibyte data which normally makes up the information to be processed on small systems. Interrupting the update procedure in the middle of a record may play havoc to the system. This procedure avoids data losses by maintaining two (2) separate memory areas, duplicating critical variables in each. Storage subsystems can consist on battery-backed RAM, magnetic disks, flash or EEPROM memories, or they can be local or remote storage subsystems. It is based on a very simple, Finite-State Machine that uses 4 States, Gray coded, to track the status of each main variable and its mirrored value in the storage device. The machine dictates a sequence that the software driver can use to write data to both the main and the backup variables. The driver sets and resets two (2) status bits variables, B0: the Main Variable status bit, and B1: the Mirror status bit. Both status bits must be recorded in the same storage medium as the data they represent. This algorithm prevents race conditions and ambiguous situations. You can enter the power-up verification routine at any time, interrupting the main flow of the program at any place, without losing any data at all. It is guaranteed that all bytes belonging to a data set are written right, or that none are stored, but non halfprocessed data will be made available to the user under any circumstances.

12

Authors: Alejandro Del Mar, Stefany Velarde, Johanna García

Even though different studies indicate that hi-tech tools can have positive effects when used for educational purposes, it is rare to see the use of these tools in the Venezuelan education field. Reasons for this vary depending on each institution, but generally they are related to the lack of economical resources or poor training of educational personnel regarding the use of technology. The main purpose of this work was to enable the incorporation of technology in the Venezuelan education. The project consisted in the development of new educational software about hygiene habits, a rare topic next to math and reading, but that also has a great level of importance and is very difficult to teach. In addition to the development, the project also consisted in measuring the impact of the software on the children’s behavior; making it possible to determine if the software application would successfully support the learning process of acquiring accurate hygiene habits. As an outcome of this project it was proven that the software tool created could in fact support the learning process of correct hygiene habits in children (3 to 5 years old) , having positive effects in three (3) different behavioral aspects: Knowledge, motivation and conduct. Making educational software is not an easy task. It comprises many activities and requires the tracking of numerous details. That is why the use of a propermethodology is required during the entire process, in order to facilitate organization and planning. Also, it is extremely important to have a team filled with experts that can pitch different perspectives that will lead to the enhancement of the software product, making the final product a successful one such is the case of “Pancho y Los Piratas” a small but important contribution to the Venezuelan education.

14

Authors: Heriberto Echezuría

A procedure that allows the preparation of elastic response spectra based on the statistical analyses of the spectral intensities and a Poisson model without memory. To guaranty the robustness of the data base, the Poisson model is also used along with the seismicity of the area, in order to obtain the distribution of the magnitudes. The procedure uses de concept of lifespan in order to apply the Poisson model to calculate the accelerations which correspond to the different return periods. The elastic spectra calculated in such a way are homogeneous and do not have any deviations related to the probability of excedance of the spectral accelerations. In addition, due to its formulation, the procedure also allows to verify if the data used to obtain the elastic spectra is in agreement with the seismic hazard of the site under study. Finally, in this article some particular statistic corresponding to the different spectral ordinates as well as to the proportionality between spectra with different return periods are presented.

14

Authors: Arnoldo José Gabaldon

La Revolución Industrial a través de sus sucesivas fases, ha signado en gran medida el derrotero de la civilización, durante los últimos doscientos años. En general tiende a concebirse su influencia limitada mayormente a los aspectos tecnológicos y económicos, subestimando sus profundas consecuencias sociales, políticas y culturales que han sido determinantes en la conformación de un paradigma societario ampliamente extendido. El impacto de este hito histórico ha sido inconmensurable, pues mas allá de la transformación rural-urbana que desencadeno en la mayoría de los países y que cambio su geografía económica, este ha influido en la organización social y política, en la conformación de hábitos de vida que antes eran desconocidos, en el aumento de la productividad de la mano de obra y en los patrones de consumo que se han establecido, entre otros muchos aspectos. La evolución de las ideas políticas en la llamada época moderna ha estado asociada a la Revolución Industrial, porque ella tuvo mucho que ver con el alumbramiento de diversos escenarios históricos, dentro de los cuales se han confrontado corrientes y posiciones ideológicas diversas. Para algunos autores, el surgimiento de la democracia en Europa o en los Estados Unidos de America, fue de la mano de la Revolución Industrial. Y el progreso cultural y técnico que hemos presenciado, ha contribuido tanto a cambiar los estilos de vida y la misma aptitud ante ella, hasta el punto que poco a poco fue surgiendo un paradigma o modelo societario con rasgos inconfundibles. A este lo he llamado el paradigma prevaleciente. Es un modelo de ámbito global que se da con mayor intensidad en los países industrializados, pero que ha tendido a difundirse al resto del planeta. Pero ese modelo esta dando señales de ser insuficiente para responder satisfactoriamente a los nuevos retos civilizatorios que el mismo ha contribuido a generar. El mundo esta en la búsqueda de un nuevo paradigma más apropiado para resolver la crisis existencial presente. Nos encontramos por lo tanto en un periodo de transición entre dos paradigmas, con todo lo incierto y fortuita que puede ser esa situación. Explorar esa hipótesis es el objetivo de este ensayo.

16

Authors: Gabriela Montoya, Jesús Ravelo

In object-oriented programming languages, the relationship that should hold between the specifications of a class and its superclass is called behavioural subtyping. In this paper we analyse the conditions that a behavioural subtype should meet during runtime assertion checking, that is, during dynamic verification. Our exploration relates such conditions for runtime assertion checking to the conditions that should be met in static verification of correctness under the principles of modular reasoning. As a result, we state and prove a theorem that connects dynamic and static verification of method calls in the presence of inheritance. The novelty of this theorem lies on the fact that the connection is an equivalence, where the implication from static to dynamic verification has been explored before but not the opposite one. This new exploration then poses that a hypothetical exhaustive testing through runtime assertion checking would be equivalent to the corresponding static verification of definite correctness, which adds solidity to runtime assertion checking. None but one of the runtime assertion checking tools that we know of can effectively detect all possible problems in class inheritance; the one exception is the tool used for Spec#, but their strategy relies on both specification inheritance and a rather substantial restriction on preconditions, requirements we could dispose of when taking our the-oretical results to a practical implementation.

22

Authors: Pedro Maglione

This paper is a summary of the Special Work presented at the UCAB on April 2010 as a requirement to achieve the degree of EXPERT IN STRUCTURAL ENGINEERING [19] and values the seismic response, pretty anomalous and not well understood with the technology of 43 years ago, which had the Petunia II building during the Caracas earthquake in July 29, 1967. This building is part of Las Petunias Residential Complex, located on the 1rst. Cross with the 1rst Avenue, Urb. Los Palos Grandes, Municipality Chacao, Caracas and was built between the years 1965 and 1966. It’s very slender; it has 21 stories and a big density of masonry. The investigation analyzes the influence that could have had the masonry during the 1967’s earthquake and values the expected structural seismic response of the later reinforced structure, according to the 1756-2001 Covenin Code [7] [22] [23], which spectrum has implicit an earthquake with a magnitude much bigger than the one which happened in the night of July 29, 1967. The mathematical models of the building before the earthquake and the building repaired and reinforced after the earthquake have been called Original Model and Reinforced Model respectively.

7

Authors: Arnaldo Gutiérrez

El eneagrama es un símbolo formado por nueve líneas, y los puntos donde se encuentran estas líneas están numerados del 1 al 9, sobre un círculo. Este símbolo facilita la ordenación y comprensión de procesos de producción, físicos, de autoconocimiento, religiosos y humanos, de una manera mucho más eficiente que otros diagramas lógicos y de control, porque con frecuencia existen múltiples soluciones creativas para un problema

12

Authors: Ing. Ana I. Aguilera, Ing. Alberto R. Subero

The objective of this paper is to present an analysis of diagnostic problem-solving in the medical field. The specification of medical problem solving methods is an important research subject due to its great applicability in current medical applications. The first part studies the diagnostic problem solving approach at different resolution levels: classical and complex cases. A collaborative and dynamic point of view of the process is also presented. Various formal theories have been proposed in the literature to explain of medical reasoning; some of these approaches proposed are reviewed in the second part. The safety-critical nature of medical applications requires the adoption of reliable engineering principles with a solid foundation for their construction. This work does not present a specific architecture of development to complex medical diagnosis systems but the most important elements, that should be considered in the development of these systems, have been presented. In the same way, this work shows that meta-reasoning approaches are the most pertinent in these kinds of applications.

16

Authors: Ing. María Elena Rangel, Ing. Alirio Villanueva

Aligned with the environmentalist politics of Shell on a worldwide basis, Shell Venezuela with a vision of sustainable development and in response to the impact generated by the Global Warming, is interested in applying measures like the execution of energy audits to its buildings. Due to this, was born the idea of evaluate the building Parque Ávila (Torre HP), where at the present the offices of Shell Venezuela in Caracas are located. This study was carry out applying the methodology of the Industrial Assessment Center of U.S.A, and it’s original concept was expanded with the evaluation of the consumption of water and the waste’s management of the building. The lifting of information was based, in most cases, in nominal data, energy consumption’s estimations of equipment and its schedule of operation, to assemble tools in the Excel program. With these tools was carried out a static simulation of building’s behavior related with the consumption of energy and water, management of waste and greenhouse gases emissions associated to these activities. As a result it was determined that the building has adequate energy efficiency in its installations and it operates inside normal parameters of consumption of water, waste’s and gases emissions. Nevertheless, certain measures were proposed to improve this efficiency, in short, medium and long-term time limit, which requires high costs of investment. Although this measures does not turn out to be profitable under the current economic conditions of the country, are very attractive since the point of view of the efficiency and the reduction of the damaged generated by gases emissions.