Search results for: Jorge Estudillo Ramirez

Authors: Jorge Estudillo Ramirez, Saul E. Pomares Hernandez

Abstract:

Multimedia distributed systems deal with heterogeneous data, such as texts, images, graphics, video and audio. The specification of temporal relations among different data types and distributed sources is an open research area. This paper proposes a fully distributed synchronization model to be used in multimedia systems. One original aspect of the model is that it avoids the use of a common reference (e.g. wall clock and shared memory). To achieve this, all possible multimedia temporal relations are specified according to their causal dependencies.

Keywords: Multimedia, Distributed Systems, Partial Ordering, Temporal Synchronization

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Authors: Jorge Ramírez-Ortiz, Jorge Medina-Valtierra, Merced Martínez Rosales

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Biodiesel production with used frying by transesterification reaction with methanol, using a commercial kaolinite thermally-activated solid acid catalyst was investigated. The surface area, the average pore diameter and pore volume of the kaolinite catalyst were 10 m2/g, 13.0 nm and 30 mm3/g, respectively. The optimal conditions for the transesterification reaction were determined to be oil/methanol, in a molar ratio 1:31, temperature 160 ºC and catalyst concentration of 3% (w/w). The yield of fatty acids methyl esters (FAME) was 92.4% after 2 h of reaction. This method of preparation of biodiesel can be a positive alternative for utilizing used frying corn oil for feedstock of biodiesel combined with the inexpensive catalyst.

Keywords: Biodiesel, frying corn oil, kaolinite, transesterification

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Authors: Jorge Ramírez-Ortiz, Merced Martínez Rosales, Horacio Flores Zúñiga

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Transesterification reactions free of catalyst between roasted chicken fat with methanol were carried out in a batch reactor in order to produce biodiesel to temperatures from 120°C to 140°C. Parameters related to the transesterification reactions, including temperature, time and the molar ratio of chicken fat to methanol also investigated. The maximum yield of the reaction was of 98% under conditions of 140°C, 4 h of reaction time and a molar ratio of chicken fat to methanol of 1:31. The biodiesel thus obtained exhibited a viscosity of 6.3 mm2/s and a density of 895.9 kg/m3. The results showed this process can be right choice to produce biodiesel since this process does not use any catalyst. Therefore, the steps of neutralization and washing are avoided, indispensables in the case of the alkaline catalysis.

Keywords: Biodiesel, non-catalyst, roasted chicken fat, transesterification.

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Authors: J. J. Cetina-Denis, R. M. López-Gutiérrez, R. Ramírez-Ramírez, C. Cruz-Hernández

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This work addresses the problem of designing an algorithm capable of generating chaotic trajectories for mobile robots. Particularly, the chaotic behavior is induced in the linear and angular velocities of a Khepera III differential mobile robot by infusing them with the states of the H´enon chaotic map. A possible application, using the properties of chaotic systems, is patrolling a work area. In this work, numerical and experimental results are reported and analyzed. In addition, two quantitative numerical tests are applied in order to measure how chaotic the generated trajectories really are.

Keywords: Chaos, chaotic trajectories, differential mobile robot, Henons map, Khepera III robot, patrolling applications.

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Authors: J. Ramírez A., A. Rubiano F.

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In this paper the direct kinematic model of a multiple applications three degrees of freedom industrial manipulator, was developed using the homogeneous transformation matrices and the Denavit - Hartenberg parameters, likewise the inverse kinematic model was developed using the same method, verifying that in the workload border the inverse kinematic presents considerable errors, therefore a genetic algorithm was implemented to optimize the model improving greatly the efficiency of the model.

Keywords: Direct Kinematic, Genetic Algorithm, InverseKinematic, Optimization, Robot Manipulator

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Authors: Jonathan Bohn, Jorge Rebaza, Kaitlin Speer

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The dynamics of a predator-prey model with continuous threshold policy harvesting functions on the prey is studied. Theoretical and numerical methods are used to investigate boundedness of solutions, existence of bionomic equilibria, and the stability properties of coexistence equilibrium points and periodic orbits. Several bifurcations as well as some heteroclinic orbits are computed.

Keywords: Predator-prey models, threshold harvesting, dynamicalsystems

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Authors: Jorge Cardoso

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Semantic Web services will enable the semiautomatic and automatic annotation, advertisement, discovery, selection, composition, and execution of inter-organization business logic, making the Internet become a common global platform where organizations and individuals communicate with each other to carry out various commercial activities and to provide value-added services. There is a growing consensus that Web services alone will not be sufficient to develop valuable solutions due the degree of heterogeneity, autonomy, and distribution of the Web. This paper deals with two of the hottest R&D and technology areas currently associated with the Web – Web services and the Semantic Web. It presents the synergies that can be created between Web Services and Semantic Web technologies to provide a new generation of eservices.

Keywords: Semantic Web, Web service, Web process, WWW.

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Authors: Y. Cifuentes, L. Beltrán, L. Ramírez

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The availability to deploy mobile applications for health care is increasing daily thru different mobile app stores. But within these capabilities the number of hacking attacks has also increased, in particular into medical mobile applications. The security vulnerabilities in medical mobile apps can be triggered by errors in code, incorrect logic, poor design, among other parameters. This is usually used by malicious attackers to steal or modify the users’ information. The aim of this research is to analyze the vulnerabilities detected in mobile medical apps according to risk factor standards defined by OWASP in 2014.

Keywords: mHealth apps, OWASP, protocols, security vulnerabilities, risk factors.

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Authors: David G. Maxínez, A. Ferreyra Ramírez, Ismael Echenique Álvarez, Francisco Javier Sánchez Rangel, Guillermo Castillo Tapia, Petra Baldivia Noyola, María Antonieta García Galván

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The project describes the modeling of various architectures mechatronics specifically morphologies of robots in an educational environment. Each structure developed by students of pre-school, primary and secondary was created using the concept of reverse engineering in a constructivist environment, to later be integrated in educational software that promotes the teaching of educational Robotics in a virtual and economic environment.

Keywords: Modeling, constructivist, engineering, reverse, robotics education, virtual, morphology.

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Authors: Yolanda Ramírez, Ángel Tejada, Agustín Baidez

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This paper shows the general perceptions of Spanish university stakeholders in relation to the university’s annual reports and the adequacy and potential of intellectual capital reporting. To this end, a questionnaire was designed and sent to every member of the Social Councils of Spanish public universities. It was thought that these participants would provide a good example of the attitude of university stakeholders since they represent the different social groups connected with universities. From the results of this study we are in the position of confirming the need for universities to offer information on intellectual capital in their accounting information model.

Keywords: Intellectual capital, disclosure, stakeholders, universities, annual report.

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Authors: Eduardo Álvarez, Gerardo Quiroga, Jorge Orozco, Gabriel Chavira

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AmI proposes a new way of thinking about computers, which follows the ideas of the Ubiquitous Computing vision of Mark Weiser. In these, there is what is known as a Disappearing Computer Initiative, with users immersed in intelligent environments. Hence, technologies need to be adapted so that they are capable of replacing the traditional inputs to the system by embedding these in every-day artifacts. In this work, we present an approach, which uses Radiofrequency Identification (RFID) and Near Field Communication (NFC) technologies. In the latter, a new form of interaction appears by contact. We compare both technologies by analyzing their requirements and advantages. In addition, we propose using a combination of RFID and NFC.

Keywords: Touching interaction, ambient intelligence, NFC, RFID.

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Authors: Jenny K. Ubaque, Edward P. Guillen, Juan S. Solórzano, Leonardo J. Ramírez

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The health care must be a right for people around the world, but in order to guarantee the access to all, it is necessary to overcome geographical barriers. Telemedicine take advantage of Information Communication Technologies to deploy health care services around the world. To achieve those goals, it is necessary to use existing last mile solution to create access for home users, which is why is necessary to establish the channel characteristics for those kinds of services. This paper presents an analysis of network performance of last mile solution for the use of IPTV broadcasting with the application of streaming for telemedicine apps.

Keywords: Telemedicine, IPTV, GPON, ADSL2+, COAXIAL, Jumbogram.

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Authors: Gilberto Gonzalez-A, Jorge Madrigal

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The steady state response of bond graphs representing passive and active suspension is presented. A bond graph with preferred derivative causality assignment to get the steady state is proposed. A general junction structure of this bond graph is proposed. The proposed methodology to passive and active suspensions is applied.

Keywords: Bond graph, steady state, active suspension.

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Authors: Jorge Barros Mendes

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The Portuguese Constitution, in article 22, instituted the general principle of tort liability of the State and other public law entities. Consequently, ordinary legislation established the tort liability of the State into the Portuguese Legal Order, by means of Decree-Law 48051, of 1967. This decree, which was criticised extensively, was amended by virtue of Law 67/2007, of 31st December, establishing the regime for tort liability arising from losses caused by third parties, due to the acts of public management in relation to all the functions of the State, i.e. i) administrative, ii) legislative, and iii) jurisdictional.

Keywords: Portuguese courts, tort liability of the state.

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Authors: Yolanda Ramírez, Ángel Tejada, Agustín Baidez

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In recent years, the intellectual capital reporting in higher education institutions has been acquiring progressive importance worldwide. Intellectual capital approaches becomes critical at universities, mainly due to the fact that knowledge is the main output as well as input in these institutions. Universities produce knowledge, either through scientific and technical research (the results of investigation, publications, etc.) or through teaching (students trained and productive relationships with their stakeholders). The purpose of the present paper is to identify the intangible elements about which university stakeholders demand most information. The results of a study done at Spanish universities are used to see which groups of universities have stakeholders who are more proactive to the disclosure of intellectual capital.

Keywords: Intellectual capital, universities, Spain, cluster analysis.

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Authors: Jorge Cardoso

Abstract:

It has been recognized that due to the autonomy and heterogeneity, of Web services and the Web itself, new approaches should be developed to describe and advertise Web services. The most notable approaches rely on the description of Web services using semantics. This new breed of Web services, termed semantic Web services, will enable the automatic annotation, advertisement, discovery, selection, composition, and execution of interorganization business logic, making the Internet become a common global platform where organizations and individuals communicate with each other to carry out various commercial activities and to provide value-added services. This paper deals with two of the hottest R&D and technology areas currently associated with the Web – Web services and the semantic Web. It describes how semantic Web services extend Web services as the semantic Web improves the current Web, and presents three different conceptual approaches to deploying semantic Web services, namely, WSDL-S, OWL-S, and WSMO.

Keywords: Semantic Web, Web service, Web process, WWW

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Authors: Yolanda Ramírez, Ángel Tejada, Agustín Baidez

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The purpose of this paper is to examine the quality of voluntary intellectual capital disclosure by public Spanish universities on their websites. To this end, a content analysis was used to analyze the websites of 50 public Spanish universities i 2016. The results of this study show that human capital was the most disclosed category with relational capital being the least frequently disclosed in Spain. However, the quality of structural capital disclosures was higher than relational and human capital. Finally, most IC disclosures were narrative in nature.

Keywords: Intellectual capital, quality disclosure, websites, universities, Spain.

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Authors: Carlos Huertas, Reyes Juarez-Ramirez

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Public health is one of the most critical issues today; therefore, there is great interest to improve technologies in the area of diseases detection. With machine learning and feature selection, it has been possible to aid the diagnosis of several diseases such as cancer. In this work, we present an extension to the Heat Map Based Feature Selection algorithm, this modification allows automatic threshold parameter selection that helps to improve the generalization performance of high dimensional data such as mass spectrometry. We have performed a comparison analysis using multiple cancer datasets and compare against the well known Recursive Feature Elimination algorithm and our original proposal, the results show improved classification performance that is very competitive against current techniques.

Keywords: Feature selection, mass spectrometry, biomarker discovery, cancer.

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Authors: R. G. Ramírez-Chavarría, C. Sánchez-Pérez, V. Argueta-Díaz

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In this paper we present the design of an optical device based on a Herriott multi-pass cell fabricated on a small sized acrylic slab for heat flux measurements using the deflection of a laser beam propagating inside the cell. The beam deflection is produced by the heat flux conducted to the acrylic slab due to a gradient in the refractive index. The use of a long path cell as the sensitive element in this measurement device, gives the possibility of high sensitivity within a small size device. We present the optical design as well as some experimental results in order to validate the device’s operation principle.

Keywords: Heat flux, herriott cell, optical beam deflection, thermal conductivity.

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Authors: M. Margarida Costa, Jorge Simão

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The minimal condition for symmetry breaking in morphogenesis of cellular population was investigated using cellular automata based on reaction-diffusion dynamics. In particular, the study looked for the possibility of the emergence of branching structures due to mechanical interactions. The model used two types of cells an external gradient. The results showed that the external gradient influenced movement of cell type-I, also revealed that clusters formed by cells type-II worked as barrier to movement of cells type-I.

Keywords: Morphogenesis, branching structures, symmetrybreaking.

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Authors: J. Ramírez-Ortiz, J. Núñez Monreal

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Due to the growth of the urban area towards lands contaminated with ancient tails, in this work we evaluated if the leaching with calcium thiosulfate (CaS2O3) for the recovery of silver, gold and mercury from this soil, also dissolves arsenic, cadmium and lead; for this, we determined their quantity per each fraction of size of particle of the soil before and after the dissolution. Half of the soil samples were leached in the plant Beneficiadora de Jales del Centro, S. A. de C.V. and the rest of them remained in the laboratory. The ICP-OES technique was used to determine the amounts of arsenic, cadmium and lead, in the samples of both lots. The soil samples were collected in a neighboring area at El Lampotal, Vetagrande, Zacatecas, México, with an extension of 600 m2 at 22º52' 37.69'' N, 102º25' 11.73'' W. The amount of arsenic, cadmium and lead found in nonleached soil and for a particle size of 47 μm was 203.72±3.73, 33.63±1.31 and 3480.99±20.4 mg/kg respectively.

Keywords: Arsenic, Cadmium, Lead, Soil, Tails.

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Authors: Yolanda Ramírez Córcoles, Ángel Tejad Ponce, Agustín Baidez González

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Intellectual capital reporting becomes critical at universities, mainly due to the fact that knowledge is the main output as well as input in these institutions. In addition, universities have continuous external demands for greater information and transparency about the use of public funds, and are increasingly provided with greater autonomy regarding their organization, management, and budget allocation. This situation requires new management and reporting systems. The purpose of the present study is to provide a model for intellectual capital report in Spanish universities. To this end, a questionnaire was sent to every member of the Social Councils of Spanish public universities in order to identify which intangible elements university stakeholders demand most. Our proposal for an intellectual capital report aims to act as a guide to help the Spanish universities on the road to the presentation of information on intellectual capital which can assist stakeholders to make the right decisions.

Keywords: Intellectual capital, Spain, report, universities.

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Authors: Marc Veillette, Antonio Avalos Ramirez, Michèle Heitz

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Among the technologies available to reduce methane emitted from the pig industry, biofiltration seems to be an effective and inexpensive solution. In methane (CH4) biofiltration, nitrogen is an important macronutrient for the microorganisms growth. The objective of this research project was to study the effect of ammonium (NH4 +) on the performance, the biomass production and the nitrogen conversion of a biofilter treating methane. For NH4 + concentrations ranging from 0.05 to 0.5 gN-NH4 +/L, the CH4 removal efficiency and the dioxide carbon production rate decreased linearly from 68 to 11.8 % and from 7.1 to 0.5 g/(m3-h), respectively. The dry biomass content varied from 4.1 to 5.8 kg/(m3 filter bed). For the same range of concentrations, the ammonium conversion decreased while the specific nitrate production rate increased. The specific nitrate production rate presented negative values indicating denitrification in the biofilter.

Keywords: Methane, biofiltration, pig, ammonium, nitrification, denitrification.

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Authors: Jorge Cardoso

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Process measurement is the task of empirically and objectively assigning numbers to the properties of business processes in such a way as to describe them. Desirable attributes to study and measure include complexity, cost, maintainability, and reliability. In our work we will focus on investigating process complexity. We define process complexity as the degree to which a business process is difficult to analyze, understand or explain. One way to analyze a process- complexity is to use a process control-flow complexity measure. In this paper, an attempt has been made to evaluate the control-flow complexity measure in terms of Weyuker-s properties. Weyuker-s properties must be satisfied by any complexity measure to qualify as a good and comprehensive one.

Keywords: Business process measurement, workflow, complexity.

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Authors: Carlos Ramirez, Carlos Concha, Benjamin Valdes

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Emotions are related with learning processes and physiological signals can be used to detect them for the personalization of learning resources and to control the pace of instruction. A model of relevant emotions has been developed, where specific combinations of emotions and cognition processes are connected and integrated with the concept of 'flow', in order to improve learning. The cardiac pulse is a reliable signal that carries useful information about the subject-s emotional condition; it is detected using a classroom chair adapted with non invasive EMFi sensor and an acquisition system that generates a ballistocardiogram (BCG), the signal is processed by an algorithm to obtain characteristics that match a specific emotional condition. The complete chair system is presented in this work, along with a framework for the personalization of learning resources.

Keywords: Ballistocardiogram, emotions in learning, noninvasive sensors, personalization of learning resources.

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Authors: R. Andreola, O. A. A. Santos, L. M. M, Jorge

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An industrial system for the production of white liquor of a paper industry, Klabin Paraná Papéis, formed by ten reactors was modeled, simulated, and analyzed. The developed model considered possible water losses by evaporation and reaction, in addition to variations in volumetric flow of lime mud across the reactors due to composition variations. The model predictions agreed well with the process measurements at the plant and the results showed that the slaking reaction is nearly complete at the third causticizing reactor, while causticizing ends by the seventh reactor. Water loss due to slaking reaction and evaporation occurs more pronouncedly in the slaking reaction than in the final causticizing reactors; nevertheless, the lime mud flow remains nearly constant across the reactors.

Keywords: Causticizing, lime, prediction, process.

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Authors: L. Ramirez, E. Guillén, J. Sánchez

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Some of the main goals about telecare such as monitoring, treatment, telediagnostic are deployed with the integration of applications with specific appliances. In order to achieve a coherent model to integrate software, hardware, and healthcare systems, different telehealth models with Internet of Things (IoT), cloud computing, artificial intelligence, etc. have been implemented, and their advantages are still under analysis. In this paper, we propose an integrated model based on IoT architecture and cloud computing telehealth center. Analytics module is presented as a solution to control an ideal diagnostic about some diseases. Specific features are then compared with the recently deployed conventional models in telemedicine. The main advantage of this model is the availability of controlling the security and privacy about patient information and the optimization on processing and acquiring clinical parameters according to technical characteristics.

Keywords: Analytics, telemedicine, internet of things, cloud computing.

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Authors: María-Dolores Cubiles-de-la-Vega, Rafael Pino-Mejías, Esther-Lydia Silva-Ramírez

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A dissimilarity measure between the empiric characteristic functions of the subsamples associated to the different classes in a multivariate data set is proposed. This measure can be efficiently computed, and it depends on all the cases of each class. It may be used to find groups of similar classes, which could be joined for further analysis, or it could be employed to perform an agglomerative hierarchical cluster analysis of the set of classes. The final tree can serve to build a family of binary classification models, offering an alternative approach to the multi-class SVM problem. We have tested this dendrogram based SVM approach with the oneagainst- one SVM approach over four publicly available data sets, three of them being microarray data. Both performances have been found equivalent, but the first solution requires a smaller number of binary SVM models.

Keywords: Cluster Analysis, Empiric Characteristic Function, Multi-class SVM, R.

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Authors: Ramirez D. Edgar I., Angeles H. José J., Ruiz C. Osvaldo, Jacobo A. Victor H., Ortiz P. Armando

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Knowledge of bone mechanical properties is important for bone substitutes design and fabrication, and more efficient prostheses development. The aim of this study is to characterize the viscoelastic behavior of bone specimens, through stress relaxation and fatigue tests performed to trabecular bone samples from bovine femoral heads. Relaxation tests consisted on preloading the samples at five different magnitudes and evaluate them for 1020 seconds, adjusting the results to a KWW mathematical model. Fatigue tests consisted of 700 load cycles and analyze their status at the end of the tests. As a conclusion we have that between relaxation stress and each preload there is linear relation and for samples with initial Young´s modulus greater than 1.5 GPa showed no effects due fatigue test loading cycles.

Keywords: Bone viscoelasticity, fatigue test, stress relaxation test, trabecular bone properties.

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Authors: Jorge Cardoso

Abstract:

Workflow Management Systems (WfMS) alloworganizations to streamline and automate business processes and reengineer their structure. One important requirement for this type of system is the management and computation of the Quality of Service(QoS) of processes and workflows. Currently, a range of Web processes and workflow languages exist. Each language can be characterized by the set of patterns they support. Developing andimplementing a suitable and generic algorithm to compute the QoSof processes that have been designed using different languages is a difficult task. This is because some patterns are specific to particular process languages and new patterns may be introduced in future versions of a language. In this paper, we describe an adaptive algorithm implemented to cope with these two problems. The algorithm is called adaptive since it can be dynamically changed as the patterns of a process language also change.

Keywords: quality of service, web processes, workflows, web services

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