Fast Correction of Tiled Display Systems on Planar Surfaces

A method for fast colour and geometric correction of a tiled display system is presented in this paper. Such kind of displays are a common choice for virtual reality applications and simulators, where a high resolution image is required. They are the cheapest and more flexible alternative for large image generation but they require a precise geometric and colour correction. The purpose of the proposed method is to correct the projection system as fast as possible so in case the system needs to be recalibrated it doesn’t interfere with the normal operation of the simulator or virtual reality application. This technique makes use of a single conventional webcam for both geometric and photometric correction. Some previous assumptions are made, like planar projection surface and negligibleintra-projector colour variation and black-offset levels. If these assumptions hold true, geometric and photometric seamlessness can be achievedfor this kind of display systems. The method described in this paper is scalable for an undefined number of projectors and completely automatic.

Robustness Analysis of Eigenstructure Assignment Controllers on Rigid-Flexible Satellites

Flexible spacecraft with attached solar panels may exhibit undesired vibrations and structural deformations. These types of vehicles show an intrinsic coupling of the elements of the structure. The attitude maneuvers performed by flexible spacecraft may cause non-desired deflections of attached flexible elements. Any attitude and orbit control system generally solves these problems using filters that are designed to attenuate the relative deflections of flexible appendages. In this paper, we propose a method for designing attitude static controllers using an eigenstructure assignment (EA) method. A set of requirements were specified from our understanding of the system modes in an open loop. Exhaustive theoretical and numerical simulations were performed on special cases to verify the controller design procedure. In the design of the controller, we considered all of the aspects that relate to the eigenstructure assignment. The primary objective of this paper is to demonstrate the feasibility of obtaining a high degree of decoupling for some selected modes via the application of an EA method. Finally a robustness analysis is perform to the system together with the designed controller by means of a mu-analysis

Estimation of the solubility parameters of model plant surfaces and agrochemicals: a valuable tool for understanding plant surface interactions

Background Most aerial plant parts are covered with a hydrophobic lipid-rich cuticle, which is the interface between the plant organs and the surrounding environment. Plant surfaces may have a high degree of hydrophobicity because of the combined effects of surface chemistry and roughness. The physical and chemical complexity of the plant cuticle limits the development of models that explain its internal structure and interactions with surface-applied agrochemicals. In this article we introduce a thermodynamic method for estimating the solubilities of model plant surface constituents and relating them to the effects of agrochemicals. Results Following the van Krevelen and Hoftyzer method, we calculated the solubility parameters of three model plant species and eight compounds that differ in hydrophobicity and polarity. In addition, intact tissues were examined by scanning electron microscopy and the surface free energy, polarity, solubility parameter and work of adhesion of each were calculated from contact angle measurements of three liquids with different polarities. By comparing the affinities between plant surface constituents and agrochemicals derived from (a) theoretical calculations and (b) contact angle measurements we were able to distinguish the physical effect of surface roughness from the effect of the chemical nature of the epicuticular waxes. A solubility parameter model for plant surfaces is proposed on the basis of an increasing gradient from the cuticular surface towards the underlying cell wall. Conclusions The procedure enabled us to predict the interactions among agrochemicals, plant surfaces, and cuticular and cell wall components, and promises to be a useful tool for improving our understanding of biological surface interactions.

Estimation of the solubility parameters of model plant surfaces and agrochemicals: a valuable tool for understanding plant surface interactions

Background Most aerial plant parts are covered with a hydrophobic lipid-rich cuticle, which is the interface between the plant organs and the surrounding environment. Plant surfaces may have a high degree of hydrophobicity because of the combined effects of surface chemistry and roughness. The physical and chemical complexity of the plant cuticle limits the development of models that explain its internal structure and interactions with surface-applied agrochemicals. In this article we introduce a thermodynamic method for estimating the solubilities of model plant surface constituents and relating them to the effects of agrochemicals. Results Following the van Krevelen and Hoftyzer method, we calculated the solubility parameters of three model plant species and eight compounds that differ in hydrophobicity and polarity. In addition, intact tissues were examined by scanning electron microscopy and the surface free energy, polarity, solubility parameter and work of adhesion of each were calculated from contact angle measurements of three liquids with different polarities. By comparing the affinities between plant surface constituents and agrochemicals derived from (a) theoretical calculations and (b) contact angle measurements we were able to distinguish the physical effect of surface roughness from the effect of the chemical nature of the epicuticular waxes. A solubility parameter model for plant surfaces is proposed on the basis of an increasing gradient from the cuticular surface towards the underlying cell wall. Conclusions The procedure enabled us to predict the interactions among agrochemicals, plant surfaces, and cuticular and cell wall components, and promises to be a useful tool for improving our understanding of biological surface interactions.

Multimodal non-rigid image registration methods for therapy and surgery planning

La planificación pre-operatoria se ha convertido en una tarea esencial en cirugías y terapias de marcada complejidad, especialmente aquellas relacionadas con órgano blando. Un ejemplo donde la planificación preoperatoria tiene gran interés es la cirugía hepática. Dicha planificación comprende la detección e identificación precisa de las lesiones individuales y vasos así como la correcta segmentación y estimación volumétrica del hígado funcional. Este proceso es muy importante porque determina tanto si el paciente es un candidato adecuado para terapia quirúrgica como la definición del abordaje a seguir en el procedimiento. La radioterapia de órgano blando es un segundo ejemplo donde la planificación se requiere tanto para la radioterapia externa convencional como para la radioterapia intraoperatoria. La planificación comprende la segmentación de tumor y órganos vulnerables y la estimación de la dosimetría. La segmentación de hígado funcional y la estimación volumétrica para planificación de la cirugía se estiman habitualmente a partir de imágenes de tomografía computarizada (TC). De igual modo, en la planificación de radioterapia, los objetivos de la radiación se delinean normalmente sobre TC. Sin embargo, los avances en las tecnologías de imagen de resonancia magnética (RM) están ofreciendo progresivamente ventajas adicionales. Por ejemplo, se ha visto que el ratio de detección de metástasis hepáticas es significativamente superior en RM con contraste Gd–EOB–DTPA que en TC. Por tanto, recientes estudios han destacado la importancia de combinar la información de TC y RM para conseguir el mayor nivel posible de precisión en radioterapia y para facilitar una descripción precisa de las lesiones del hígado. Con el objetivo de mejorar la planificación preoperatoria en ambos escenarios se precisa claramente de un algoritmo de registro no rígido de imagen. Sin embargo, la gran mayoría de sistemas comerciales solo proporcionan métodos de registro rígido. Las medidas de intensidad de voxel han demostrado ser criterios de similitud de imágenes robustos, y, entre ellas, la Información Mutua (IM) es siempre la primera elegida en registros multimodales. Sin embargo, uno de los principales problemas de la IM es la ausencia de información espacial y la asunción de que las relaciones estadísticas entre las imágenes son homogéneas a lo largo de su domino completo. La hipótesis de esta tesis es que la incorporación de información espacial de órganos al proceso de registro puede mejorar la robustez y calidad del mismo, beneficiándose de la disponibilidad de las segmentaciones clínicas. En este trabajo, se propone y valida un esquema de registro multimodal no rígido 3D usando una nueva métrica llamada Información Mutua Centrada en el Órgano (Organ-Focused Mutual Information metric (OF-MI)) y se compara con la formulación clásica de la Información Mutua. Esto permite mejorar los resultados del registro en áreas problemáticas incorporando información regional al criterio de similitud, beneficiándose de la disponibilidad real de segmentaciones en protocolos estándares clínicos, y permitiendo que la dependencia estadística entre las dos modalidades de imagen difiera entre órganos o regiones. El método propuesto se ha aplicado al registro de TC y RM con contraste Gd–EOB–DTPA así como al registro de imágenes de TC y MR para planificación de radioterapia intraoperatoria rectal. Adicionalmente, se ha desarrollado un algoritmo de apoyo de segmentación 3D basado en Level-Sets para la incorporación de la información de órgano en el registro. El algoritmo de segmentación se ha diseñado específicamente para la estimación volumétrica de hígado sano funcional y ha demostrado un buen funcionamiento en un conjunto de imágenes de TC abdominales. Los resultados muestran una mejora estadísticamente significativa de OF-MI comparada con la Información Mutua clásica en las medidas de calidad de los registros; tanto con datos simulados (p<0.001) como con datos reales en registro hepático de TC y RM con contraste Gd– EOB–DTPA y en registro para planificación de radioterapia rectal usando OF-MI multi-órgano (p<0.05). Adicionalmente, OF-MI presenta resultados más estables con menor dispersión que la Información Mutua y un comportamiento más robusto con respecto a cambios en la relación señal-ruido y a la variación de parámetros. La métrica OF-MI propuesta en esta tesis presenta siempre igual o mayor precisión que la clásica Información Mutua y consecuentemente puede ser una muy buena alternativa en aplicaciones donde la robustez del método y la facilidad en la elección de parámetros sean particularmente importantes. Abstract Pre-operative planning has become an essential task in complex surgeries and therapies, especially for those affecting soft tissue. One example where soft tissue preoperative planning is of high interest is liver surgery. It involves the accurate detection and identification of individual liver lesions and vessels as well as the proper functional liver segmentation and volume estimation. This process is very important because it determines whether the patient is a suitable candidate for surgical therapy and the type of procedure. Soft tissue radiation therapy is a second example where planning is required for both conventional external and intraoperative radiotherapy. It involves the segmentation of the tumor target and vulnerable organs and the estimation of the planned dose. Functional liver segmentations and volume estimations for surgery planning are commonly estimated from computed tomography (CT) images. Similarly, in radiation therapy planning, targets to be irradiated and healthy and vulnerable tissues to be protected from irradiation are commonly delineated on CT scans. However, developments in magnetic resonance imaging (MRI) technology are progressively offering advantages. For instance, the hepatic metastasis detection rate has been found to be significantly higher in Gd–EOB–DTPAenhanced MRI than in CT. Therefore, recent studies highlight the importance of combining the information from CT and MRI to achieve the highest level of accuracy in radiotherapy and to facilitate accurate liver lesion description. In order to improve those two soft tissue pre operative planning scenarios, an accurate nonrigid image registration algorithm is clearly required. However, the vast majority of commercial systems only provide rigid registration. Voxel intensity measures have been shown to be robust measures of image similarity, and among them, Mutual Information (MI) is always the first candidate in multimodal registrations. However, one of the main drawbacks of Mutual Information is the absence of spatial information and the assumption that statistical relationships between images are the same over the whole domain of the image. The hypothesis of the present thesis is that incorporating spatial organ information into the registration process may improve the registration robustness and quality, taking advantage of the clinical segmentations availability. In this work, a multimodal nonrigid 3D registration framework using a new Organ- Focused Mutual Information metric (OF-MI) is proposed, validated and compared to the classical formulation of the Mutual Information (MI). It allows improving registration results in problematic areas by adding regional information into the similitude criterion taking advantage of actual segmentations availability in standard clinical protocols and allowing the statistical dependence between the two modalities differ among organs or regions. The proposed method is applied to CT and T1 weighted delayed Gd–EOB–DTPA-enhanced MRI registration as well as to register CT and MRI images in rectal intraoperative radiotherapy planning. Additionally, a 3D support segmentation algorithm based on Level-Sets has been developed for the incorporation of the organ information into the registration. The segmentation algorithm has been specifically designed for the healthy and functional liver volume estimation demonstrating good performance in a set of abdominal CT studies. Results show a statistical significant improvement of registration quality measures with OF-MI compared to MI with both simulated data (p<0.001) and real data in liver applications registering CT and Gd–EOB–DTPA-enhanced MRI and in registration for rectal radiotherapy planning using multi-organ OF-MI (p<0.05). Additionally, OF-MI presents more stable results with smaller dispersion than MI and a more robust behavior with respect to SNR changes and parameters variation. The proposed OF-MI always presents equal or better accuracy than the classical MI and consequently can be a very convenient alternative within applications where the robustness of the method and the facility to choose the parameters are particularly important.

Tratamiento consistente de restricciones e impacto en dinámica de sistemas multicuerpo

Esta tesis está enmarcada en el estudio de diferentes procedimientos numéricos para resolver la dinámica de un sistema multicuerpo sometido a restricciones e impacto, que puede estar compuesto por sólidos rígidos y deformables conectados entre sí por diversos tipos de uniones. Dentro de los métodos numéricos analizados se presta un especial interés a los métodos consistentes, los cuales tienen por objetivo que la energía calculada en cada paso de tiempo, para un sistema mecánico, tenga una evolución coherente con el comportamiento teórico de la energía. En otras palabras, un método consistente mantiene constante la energía total en un problema conservativo, y en presencia de fuerzas disipativas proporciona un decremento positivo de la energía total. En esta línea se desarrolla un algoritmo numérico consistente con la energía total para resolver las ecuaciones de la dinámica de un sistema multicuerpo. Como parte de este algoritmo se formulan energéticamente consistentes las restricciones y el contacto empleando multiplicadores de Lagrange, penalización y Lagrange aumentado. Se propone también un método para el contacto con sólidos rígidos representados mediante superficies implícitas, basado en una restricción regularizada que se adaptada adecuadamente para el cumplimiento exacto de la restricción de contacto y para ser consistente con la conservación de la energía total. En este contexto se estudian dos enfoques: uno para el contacto elástico puro (sin deformación) formulado con penalización y Lagrange aumentado; y otro basado en un modelo constitutivo para el contacto con penetración. En el segundo enfoque se usa un potencial de penalización que, en ausencia de componentes disipativas, restaura la energía almacenada en el contacto y disipa energía de forma consistente con el modelo continuo cuando las componentes de amortiguamiento y fricción son consideradas. This thesis focuses on the study of several numerical procedures used to solve the dynamics of a multibody system subjected to constraints and impact. The system may be composed by rigid and deformable bodies connected by different types of joints. Within this framework, special attention is paid to consistent methods, which preserve the theoretical behavior of the energy at each time step. In other words, a consistent method keeps the total energy constant in a conservative problem, and provides a positive decrease in the total energy when dissipative forces are present. A numerical algorithm has been developed for solving the dynamical equations of multibody systems, which is energetically consistent. Energetic consistency in contacts and constraints is formulated using Lagrange multipliers, penalty and augmented Lagrange methods. A contact methodology is proposed for rigid bodies with a boundary represented by implicit surfaces. The method is based on a suitable regularized constraint formulation, adapted both to fulfill exactly the contact constraint, and to be consistent with the conservation of the total energy. In this context two different approaches are studied: the first applied to pure elastic contact (without deformation), formulated with penalty and augmented Lagrange; and a second one based on a constitutive model for contact with penetration. In this second approach, a penalty potential is used in the constitutive model, that restores the energy stored in the contact when no dissipative effects are present. On the other hand, the energy is dissipated consistently with the continuous model when friction and damping are considered.

Analytic free-form lens design in 3D: coupling three ray sets using two lens surfaces

The two-dimensional analytic optics design method presented in a previous paper [Opt. Express 20, 5576–5585 (2012)] is extended in this work to the three-dimensional case, enabling the coupling of three ray sets with two free-form lens surfaces. Fermat’s principle is used to deduce additional sets of functional differential equations which make it possible to calculate the lens surfaces. Ray tracing simulations demonstrate the excellent imaging performance of the resulting free-form lenses described by more than 100 coefficients.

Diffuse illuminance availability on horizontal and vertical surfaces at Madrid, Spain

The overall objective of this work is to provide diffuse illuminance availability at Madrid (Spain) through a statistical analysis of illuminance values corresponding to a long-term data series. The illuminance values are obtained from irradiance measurements by means of different empirical models for luminous efficacy. The values of diffuse illuminance on a horizontal and on vertical surfaces facing the four cardinal points are estimated and the different aspects related to daylight availability in an area with specific climatic conditions are analyzed. The experimental data consist of global and diffuse irradiance measurements on a horizontal surface provided by the National Meteorological Agency in Spain (AEMET) for Madrid. These data consist of hourly values measured in the period of 1980–2005. The statistical results derived correspond to a daylight typical year for the five surfaces considered. This information will be useful to building experts to estimate natural illumination availability when daylighting techniques are applied in building design with the main aim of electric energy savings.

Freeform Optical Surfaces: Report from OSA's First Incubator Meeting

Just as business incubator programs are designed to support the development of fledgling companies, OSA?s new incubator meeting series is structured to encourage the growth of exciting new areas within optics. The first one was devoted to the topic of freeform optics-a field that is actively evolving due to recent technological advances.

In situ study of Ge(100) surfaces with tertiarybutylphosphine supply in vapor phase epitaxy ambient

GaInP nucleation on Ge(100) often starts by annealing of the Ge(100) substrates under supply of phosphorus precursors. However, the influence on the Ge surface is not well understood. Here, we studied vicinal Ge(100) surfaces annealed under tertiarybutylphosphine (TBP) supply in MOVPE by in situ reflection anisotropy spectroscopy (RAS), X-ray photoelectron spectroscopy (XPS), and low energy electron diffraction (LEED). While XPS reveals a P termination and the presence of carbon on the Ge surface, LEED patterns indicate a disordered surface probably due to by-products of the TBP pyrolysis. However, the TBP annealed Ge(100) surface exhibits a characteristic RA spectrum, which is related to the P termination. RAS allows us to in situ control phosphorus desorption dependent on temperature.

In situ control of As dimer orientation on Ge(100) surfaces

We investigated the preparation of single domain Ge(100):As surfaces in a metal-organic vapor phase epitaxy reactor. In situ reflection anisotropy spectra (RAS) of vicinal substrates change when arsenic is supplied either by tertiarybutylarsine or by background As4 during annealing. Low energy electron diffraction shows mutually perpendicular orientations of dimers, scanning tunneling microscopy reveals distinct differences in the step structure, and x-ray photoelectron spectroscopy confirms differences in the As coverage of the Ge(100): As samples. Their RAS signals consist of contributions related to As dimer orientation and to step structure, enabling precise in situ control over preparation of single domain Ge(100): As surfaces.

Inorganic hydrophobic coatings: Surfaces mimicking the nature

Added value products are being developed in ceramic industry. Different optical effects as bright metallic shine or new functionalities as hydrophobicity or bactericide characteristics are the new properties searched on the tiles. In this study, we prepare glassy coatings for tiles based on copper pigment by a conventional industrial process. The obtained coatings present different aesthetical aspects, including bright metallic aspect which confers a high decorative value to the tile. Furthermore, these metallic coatings present hydrophobic properties with contact angles with water as high as 115 degrees and also bactericide characteristics. Superficial microstructure and nanoparticles were found in the bactericide-hydrophobic samples, resembling the surface of hydrophobic leaf surfaces. This structure was formed by the crystallization of CuO nanoparticles as Tenorite due to the copper saturation of the glassy matrix at the surface of the coatings.

Perfect imaging of three object points with only two analytic lens surfaces in two dimensions

In this work, a new two-dimensional analytic optics design method is presented that enables the coupling of three ray sets with two lens profiles. This method is particularly promising for optical systems designed for wide field of view and with clearly separated optical surfaces. However, this coupling can only be achieved if different ray sets will use different portions of the second lens profile. Based on a very basic example of a single thick lens, the Simultaneous Multiple Surfaces design method in two dimensions (SMS2D) will help to provide a better understanding of the practical implications on the design process by an increased lens thickness and a wider field of view. Fermat?s principle is used to deduce a set of functional differential equations fully describing the entire optical system. The transformation of these functional differential equations into an algebraic linear system of equations allows the successive calculation of the Taylor series coefficients up to an arbitrary order. The evaluation of the solution space reveals the wide range of possible lens configurations covered by this analytic design method. Ray tracing analysis for calculated 20th order Taylor polynomials demonstrate excellent performance and the versatility of this new analytical optics design concept.

Diseño y comportamiento de uniones estructurales mecánicas y adhesivas. Condiciones superficiales y operacionales

Las uniones estructurales mecánicas y adhesivas requieren la combinación de un número importante de parámetros para la obtención de la continuidad estructural que exigen las condiciones de diseño. Las características de las uniones presentan importantes variaciones, ligadas a las condiciones de ejecución, tanto en uniones mecánicas como especialmente en uniones adhesivas y mixtas (unión mecánica y adhesiva, también conocidas como uniones híbridas). Las propiedades mecánicas de las uniones adhesivas dependen de la naturaleza y propiedades de los adhesivos y también de muchos otros parámetros que influyen directamente en el comportamiento de estas uniones. Algunos de los parámetros más significativos son: el acabado superficial de los materiales, área y espesor de la capa adhesiva, diseño adecuado, secuencia de aplicación, propiedades químicas de la superficie y preparación de los sustratos antes de aplicar el adhesivo. Los mecanismos de adhesión son complejos. En general, cada unión adhesiva solo puede explicarse considerando la actuación conjunta de varios mecanismos de adhesión. No existen adhesivos universales para un determinado material o aplicación, por lo que cada pareja sustrato-adhesivo requiere un particular estudio y el comportamiento obtenido puede variar, significativamente, de uno a otro caso. El fallo de una junta adhesiva depende del mecanismo cohesión-adhesión, ligado a la secuencia y modo de ejecución de los parámetros operacionales utilizados en la unión. En aplicaciones estructurales existen un número muy elevado de sistemas de unión y de posibles sustratos. En este trabajo se han seleccionado cuatro adhesivos diferentes (cianoacrilato, epoxi, poliuretano y silano modificado) y dos procesos de unión mecánica (remachado y clinchado). Estas uniones se han aplicado sobre chapas de acero al carbono en diferentes estados superficiales (chapa blanca, galvanizada y prepintada). Los parámetros operacionales analizados han sido: preparación superficial, espesor del adhesivo, secuencia de aplicación y aplicación de presión durante el curado. Se han analizado tanto las uniones individuales como las uniones híbridas (unión adhesiva y unión mecánica). La combinación de procesos de unión, sustratos y parámetros operacionales ha dado lugar a la preparación y ensayo de más de mil muestras. Pues, debido a la dispersión de resultados característica de las uniones adhesivas, para cada condición analizada se han ensayado seis probetas. Los resultados obtenidos han sido: El espesor de adhesivo utilizado es una variable muy importante en los adhesivos flexibles, donde cuanto menor es el espesor del adhesivo mayor es la resistencia mecánica a cortadura de la unión. Sin embargo en los adhesivos rígidos su influencia es mucho menor. La naturaleza de la superficie es fundamental para una buena adherencia del adhesivo al substrato, que repercute en la resistencia mecánica de la unión. La superficie que mejor adherencia presenta es la prepintada, especialmente cuando existe una alta compatibilidad entre la pintura y el adhesivo. La superficie que peor adherencia tiene es la galvanizada. La secuencia de aplicación ha sido un parámetro significativo en las uniones híbridas, donde los mejores resultados se han obtenido cuando se aplicaba primero el adhesivo y la unión mecánica se realizaba antes del curado del adhesivo. La aplicación de presión durante el curado se ha mostrado un parámetro significativo en los adhesivos con poca capacidad para el relleno de la junta. En los otros casos su influencia ha sido poco relevante. El comportamiento de las uniones estructurales mecánicas y adhesivas en cuanto a la resistencia mecánica de la unión puede variar mucho en función del diseño de dicha unión. La resistencia mecánica puede ser tan grande que falle antes el substrato que la unión. Las mejores resistencias se consiguen diseñando las uniones con adhesivo cianoacrilato, eligiendo adecuadamente las condiciones superficiales y operacionales, por ejemplo chapa blanca aplicando una presión durante el curado de la unión. La utilización de uniones mixtas aumenta muy poco o nada la resistencia mecánica, pero a cambio proporciona una baja dispersión de resultados, siendo destacable para la superficie galvanizada, que es la que presenta peor reproducibilidad cuando se realizan uniones sólo con adhesivo. Las uniones mixtas conducen a un aumento de la deformación antes de la rotura. Los adhesivos dan rotura frágil y las uniones mecánicas rotura dúctil. La unión mixta proporciona ductilidad a la unión. Las uniones mixtas también pueden dar rotura frágil, esto sucede cuando la resistencia del adhesivo es tres veces superior a la resistencia de la unión mecánica. Las uniones híbridas mejoran la rigidez de la junta, sobre todo se aprecia un aumento importante en las uniones mixtas realizadas con adhesivos flexibles, pudiendo decirse que para todos los adhesivos la rigidez de la unión híbrida es superior. ABSTRACT The mechanical and adhesive structural joints require the combination of a large number of parameters to obtain the structural continuity required for the design conditions. The characteristics of the junctions have important variations, linked to performance conditions, in mechanical joints as particular in mixed adhesive joints (mechanical and adhesive joints, also known as hybrid joints). The mechanical properties of the adhesive joints depend of the nature and properties of adhesives and also of many other parameters that directly influence in the behavior of these joints. Some of the most significant parameters are: the surface finished of the material, area and thickness of the adhesive layer, suitable design, and application sequence, chemical properties of the surface and preparation of the substrate before applying the adhesive. Adhesion mechanisms are complex. In general, each adhesive joint can only be explained by considering the combined action of several adhesions mechanisms. There aren’t universal adhesives for a given material or application, so that each pair substrate-adhesive requires a particular study and the behavior obtained can vary significantly from one to another case. The failure of an adhesive joint depends on the cohesion-adhesion mechanism, linked to the sequence and manner of execution of the operational parameters used in the joint. In the structural applications, there are a very high number of joining systems and possible substrates. In this work we have selected four different adhesives (cyanoacrylate, epoxy, polyurethane and silano modified) and two mechanical joining processes (riveting and clinching). These joints were applied on carbon steel with different types of surfaces (white sheet, galvanized and pre-painted). The operational parameters analyzed were: surface preparation, thickness of adhesive, application sequence and application of pressure during curing. We have analyzed individual joints both as hybrid joints (adhesive joint and mechanical joint). The combination of joining processes, substrates and operational parameters has resulted in the preparation and testing of over a thousand specimens. Then, due to the spread of results characteristic of adhesive joints, for each condition analyzed we have tested six samples. The results have been: The thickness of adhesive used is an important variable in the flexible adhesives, where the lower the adhesive thickness greater the shear strength of the joint. However in rigid adhesives is lower influence. The nature of the surface is essential for good adherence of the adhesive to the substrate, which affects the shear strength of the joint. The surface has better adherence is preprinted, especially when there is a high compatibility between the paint and the adhesive. The surface which has poor adherence is the galvanized. The sequence of application has been a significant parameter in the hybrid junctions, where the best results are obtained when applying first the adhesive and the mechanical joint is performed before cured of the adhesive. The application of pressure during curing has shown a significant parameter in the adhesives with little capacity for filler the joint. In other cases their influence has been less relevant. The behavior of structural mechanical and adhesive joints in the shear strength of the joint can vary greatly depending on the design of such a joint. The shear strength may be so large that the substrate fails before the joint. The best shear strengths are achieved by designing the junctions with cyanoacrylate adhesive, by selecting appropriately the surface and operating conditions, for example by white sheet applying a pressure during curing of the joint. The use of hybrid joints no increase shear strength, but instead provides a low dispersion of results, being remarkable for the galvanized surface, which is the having worst reproducibility when performed bonded joints. The hybrid joints leading to increased deformation before rupture. The joints witch adhesives give brittle fracture and the mechanics joints give ductile fracture. Hybrid joint provides ductility at the joint. Hybrid joint can also give brittle fracture, this happens when the shear strength of the adhesive is three times the shear strength of the mechanical joint. The hybrid joints improve stiffness of joint, especially seen a significant increase in hybrid joints bonding with flexible adhesives, can be said that for all the adhesives, the hybrid junction stiffness is higher.