993 resultados para Flow Chart


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Radial velocities measured from near-infrared (NIR) spectra are a potential tool to search for extrasolar planets around cool stars. High resolution infrared spectrographs now available reach the high precision of visible instruments, with a constant improvement over time. GIANO is an infrared echelle spectrograph and it is a powerful tool to provide high resolution spectra for accurate radial velocity measurements of exo-planets and for chemical and dynamical studies of stellar or extragalactic objects. No other IR instruments have the GIANO's capability to cover the entire NIR wavelength range. In this work we develop an ensemble of IDL procedures to measure high precision radial velocities on a few GIANO spectra acquired during the commissioning run, using the telluric lines as wevelength reference. In Section 1.1 various exoplanet search methods are described. They exploit different properties of the planetary system. In Section 1.2 we describe the exoplanet population discovered trough the different methods. In Section 1.3 we explain motivations for NIR radial velocities and the challenges related the main issue that has limited the pursuit of high-precision NIR radial velocity, that is, the lack of a suitable calibration method. We briefly describe calibration methods in the visible and the solutions for IR calibration, for instance, the use of telluric lines. The latter has advantages and problems, described in detail. In this work we use telluric lines as wavelength reference. In Section 1.4 the Cross Correlation Function (CCF) method is described. This method is widely used to measure the radial velocities.In Section 1.5 we describe GIANO and its main science targets. In Chapter 2 observational data obtained with GIANO spectrograph are presented and the choice criteria are reported. In Chapter 3 we describe the detail of the analysis and examine in depth the flow chart reported in Section 3.1. In Chapter 4 we give the radial velocities measured with our IDL procedure for all available targets. We obtain an rms scatter in radial velocities of about 7 m/s. Finally, we conclude that GIANO can be used to measure radial velocities of late type stars with an accuracy close to or better than 10 m/s, using telluric lines as wevelength reference. In 2014 September GIANO is being operative at TNG for Science Verification and more observational data will allow to further refine this analysis.

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While there are reports of developing sexual relationships on the Internet (I) among MSM, there are few reports that have examined the process of developing sexual relationships on the I and comparing to that in real life (IRL). This study examines the process to provide insight into how MSM make decisions about courtship, engages in negotiations for sex, and choose sexual partners and examines the comparative sexual risks taken between I vs. IRL negotiation. This self-selected convenience sample at a national level (n=1001) of MSM recruited through the I, systematically explored the different steps, the process of courtship in a flow chart of I and IRL dating to portray the process of filtering, courtship and/or negotiation for sex. Risk behaviors in both environments are presented along with interactions that create predictable sequences or "scripts". These sequences constitute 'filtering' and 'sexual positioning'. Differences between I & IRL suggest discussion of HIV/STD status to have consistent differences for all variables except 'unprotected sex' meaning no condom use. There was more communication on the I in regards to self revealing information or variables relating to reducing risks which enable 'filtering' (including serosorting). Data indicate more steps in the I process, providing more complex, multiple steps to filter and position with regard not only to HIV/STD risk but also to negotiate position for complementary sexual interest. The study established a pattern of MSM's courtships or negotiation for sex and a pattern of acquisition, and more I negotiation. Data suggest negotiation opportunities which could lend to intervention to advise people how to negotiate safely. ^ Previous studies have reviewed MSM and drug use. This is a study to review the process of drug use associated with sexual behavior regarding the Internet (I) and in real life (IRL) using a self-selected, convenience sample of MSM (n=1001) recruited nation-wide through the Internet. Data on MSM and drugs illustrate the Internet being used as a tool to filter for drug use among MSM. MSM's drug use in both environments highlights the use of sexual performance drugs with an IRL pursuit of intimacy or negotiation for sex. IRL encounters were more likely to involve drug use (both recreational and sexual performance-enhancing) than Internet encounters. This may be due to more IRL meetings occurring at bars, clubs or parties where drug use is a norm. Compared with IRL, the Internet may provide a venue for persons who do not want to use drugs to select partners with similar attitudes. This suggests that filtering may be occurring as part of the internet negotiation. Data indicated that IRL persons get drunk/high before having sex in past 60 days significantly more often than Internet participants. Age did not alter the pattern of results. Thus drug filtering is really not recreational drug filtering or selecting for PNP, but appears to be situationally-based. Thus, it should perhaps be seen as another form of filtering to select drug-free partners, rather than using the Internet to specifically recruit and interact with other recreational drug users. ^

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A discussion of nonlinear dynamics, demonstrated by the familiar automobile, is followed by the development of a systematic method of analysis of a possibly nonlinear time series using difference equations in the general state-space format. This format allows recursive state-dependent parameter estimation after each observation thereby revealing the dynamics inherent in the system in combination with random external perturbations.^ The one-step ahead prediction errors at each time period, transformed to have constant variance, and the estimated parametric sequences provide the information to (1) formally test whether time series observations y(,t) are some linear function of random errors (ELEM)(,s), for some t and s, or whether the series would more appropriately be described by a nonlinear model such as bilinear, exponential, threshold, etc., (2) formally test whether a statistically significant change has occurred in structure/level either historically or as it occurs, (3) forecast nonlinear system with a new and innovative (but very old numerical) technique utilizing rational functions to extrapolate individual parameters as smooth functions of time which are then combined to obtain the forecast of y and (4) suggest a measure of resilience, i.e. how much perturbation a structure/level can tolerate, whether internal or external to the system, and remain statistically unchanged. Although similar to one-step control, this provides a less rigid way to think about changes affecting social systems.^ Applications consisting of the analysis of some familiar and some simulated series demonstrate the procedure. Empirical results suggest that this state-space or modified augmented Kalman filter may provide interesting ways to identify particular kinds of nonlinearities as they occur in structural change via the state trajectory.^ A computational flow-chart detailing computations and software input and output is provided in the body of the text. IBM Advanced BASIC program listings to accomplish most of the analysis are provided in the appendix. ^

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This paper presents the application of BIE techniques to elastoplastic three-dimensional problems. Along with the general procedures the needed integrations are described in detail and so is the flow chart of the written program.

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Tanto el tema de esta investigación, como sus objetivos, fundamentos, materiales seleccionados y parte experimental para alcanzarlos, han sido promovidos por la situación y el estado de las construcciones de hormigón armado que se comenzaron a realizar en España a partir del año 1975, con hormigones y morteros de cemento que contenían cenizas volantes hasta un 20 %, en principio, y hasta un 35 %, más tarde, de su dosificación de cemento Portland (CP), los cuales y en contra de lo esperado, han demandado y continúan demandando, muy a pesar de sus aparentes bondades de todo tipo que se les atribuían, una necesidad de mejora de sus prestaciones, especialmente, debido a un nivel inesperadamente bajo de la durabilidad de algunas obras construidas con los mismos. Todo era debido, en definitiva, a que las adiciones puzolánicas, naturales y artificiales, tales como las cenizas volantes, referidas antes, se vienen utilizando reglamentariamente para la fabricación de cementos y/o de sus productos derivados, hormigones, morteros y pastas, en la mayor parte de los países industrializados, desde hace ya más de tres décadas aproximadamente, en las mismas condiciones e idénticos usos constructivos que los hormigones y morteros de CP puro, viniendo además, dictada dicha utilización de estos materiales residuales, hoy sub-productos industriales, por cuestiones medioambientales y/o económicas, principalmente, motivo por el cual esta Tesis Doctoral ha pretendido responder también, adecuadamente y de manera esquemática (en forma de diagrama de flujo), a los criterios que deben de tenerse en cuenta a la hora de su selección y caracterización normalizada y reglamentada de estas adiciones minerales activas, sobre todo, antes de su dosificación y uso en forma del denominado cemento Portland con puzolana, o con ceniza volante, o con esquistos calcinados o con puzolanas calcinadas o con humo de sílice, cemento Portland mixto, cemento puzolánico o cemento compuesto, para que dichos problemas no se le produzcan al hormigón armado ni en masa. De aquí el enfoque tan particular y especial de esta investigación, al haberla circunscrito únicamente a las puzolanas naturales y artificiales, por considerarlas todas ellas, independientemente de por su origen, como materiales constituidos por pequeñas fracciones cristalinas distribuidas aleatoriamente en una matriz mayoritariamente vítrea y/o amorfa, la cual es la que le confiere su reactividad con el hidróxido de calcio en forma de cal apagada o de portlandita procedente de la hidratación del CP. A su vez, dichas fracciones vítreas y/o amorfas están constituidas, en su mayor parte, por sílice reactiva, SiO2r-, alúmina reactiva, Al2O3r-, y óxido de hierro reactivo, Fe2O3r-, recibiendo además, en conjunto, el nombre específico de "factores hidráulicos" de la puzolana, los cuales, por lo común, difieren cuantitativamente de sus contenidos totales, determinados por fusión alcalina mediante procedimientos normalizados. De los tres óxidos reactivos mencionados y desde el punto de vista técnico, los más importantes por su mayor presencia en casi todas las puzolanas naturales y artificiales y, también, transcendencia en la durabilidad química que les pueden llegar a conferir al hormigón armado y en masa, mortero o pasta de cemento que las contenga, son la SiO2r- y la Al2O3r-. El primero de los dos, la SiO2r-, reacciona nada más que con la portlandita (y el Ca(OH)2) para formar geles C-S-H, más tarde transformados en tobermoritas o en jennitas, semejantes a los que originan la alita y la belita del CP en su hidratación. Y desde el punto de vista normativo, la presencia de esta fracción silícica reactiva en las puzolanas viene regulada por la norma EN 197-1, de modo general, siendo además referida por la norma EN 450-1:2006, en el contexto de las cenizas volantes en su adición al hormigón, como "un polvo fino de partículas principalmente de forma esférica y cristalina, procedentes de la combustión de carbón pulverizado, que tiene propiedades puzolánicas y que está compuesto fundamentalmente de SiO2 y Al2O3". Además y de acuerdo con la primera de las dos normas, "El contenido de dióxido de silicio reactivo (definido y determinado según la norma EN 196-2 o su equivalente la UNE 80225) no debe ser inferior al 25 % en masa". Por su parte, cuantiosos estudios experimentales realizados por Talero solo y con otros investigadores, han demostrado que si la puzolana no es adecuada en calidad ni en cantidad, la durabilidad del cemento del que forme parte, y, por consiguiente, de los productos derivados que con él se fabriquen, hormigones, morteros, pastas y prefabricados, puede llegar a ser anormalmente baja, porque la alúmina reactiva, Al2O3r-, o alúmina tetra- o penta-coordinada que la constituye, se implica como tal, de una forma muy directa y con resultados totalmente contrapuestos incluso, en los ataques químicos agresivos naturales que se les producen, provenientes de terrenos y aguas selenitosas (sulfatos, que atacan en su caso al propio material hormigón, mortero y pasta que la contiene para formar ettringita de rápida formación, ett-rf, la cual puede llegar incluso a provocar un ataque rápido del yeso), del rocío marino y de las sales de deshielo (cloruros, que atacan, en cambio, a las armaduras de acero del hormigón provocándoles su corrosión electroquímica por "picadura", si bien, en este otro ataque químico, dicha Al2O3r- lo que origina es sal de Friedel de rápida formación, sF-rf, también, cuyo efecto es, en cambio, colmatador y protector, en definitiva, de dicha corrosión electroquímica), del agua de mar (acción agresiva mutua de cloruros y sulfatos), de la carbonatación, de la reactividad árido-álcali, además de intervenir en la liberación del calor de hidratación, así como también, en el comportamiento reológico de sus pastas, etc., acortándoles de este modo su durabilidad prevista y, en ocasiones, muy seriamente incluso. Pero lo más paradójico de todo es, que a pesar de su referido comportamiento totalmente contrapuesto, frente a sulfatos y cloruros, - aún no se dispone de un método de análisis químico para su determinación cuantitativa, que sea además relativamente sencillo en su operatividad, veraz, preciso, de respuesta rápida, desde el punto de vista técnico de la construcción (no más de 28 días), repetible, reproducible, que no implique peligro alguno para la seguridad vital de las personas que lo tengan que manipular y poner en práctica, económico, y que sirva también tanto para investigación -vertiente científica-, como, sobre todo, para control de calidad -vertiente técnica-, - y ni mucho menos tampoco se dispone todavía, de especificación química alguna que precise el contenido máximo de Al2O3r- (%) que tiene que poseer una puzolana natural o artificial, para poder ser añadida al cemento Portland y/o al hormigón que va a estar sometido a un determinado ataque químico agresivo de los mencionados antes, y, en especial, a sulfatos, a cloruros o al agua de mar. Y para mayor justificación de ambas necesidades, se ha de decir también que la vigente Instrucción de Hormigón Estructural EHE-08 no contempla tampoco especificación química alguna sobre los "factores hidráulicos", en general, ni del contenido de Al2O3r-(%) de las cenizas volantes, muy en particular, en su Artículo 30º "Adiciones", ni en ningún otro Artículo, a pesar de que sí contempla, en cambio, - otras especificaciones químicas que carecen del necesario significado en cuanto a la necesidad de llevar explícita o implícitamente, el mensaje de la Durabilidad Química deseado, y - el Artículo 37º, el cual y para mayor abundamiento se titula paradójicamente "Durabilidad del hormigón y de las armaduras". Asimismo, tampoco se contempla en la última versión que acaba de publicarse de la norma EN 197-1 titulada: "Cementos. Parte 1: Composición, especificaciones y criterios de conformidad de los cementos comunes". Ni tampoco, en la norma EN 450-1:2006 titulada "Cenizas volantes para hormigón. Parte 1: Definiciones, especificaciones y criterios de conformidad", ni en la vigente Instrucción española para la Recepción de Cementos, RC-08, ni en la norma ASTM C618-03 tampoco. La única especificación química que ambas normas, la europea y la norteamericana, refieren es aquella que dice que la suma de los contenidos porcentuales de SiO2 total, Al2O3 total y Fe2O3 total, de la puzolana natural o artificial, ha de ser mayor o igual que 70 %, definiendo, además, a las puzolanas de este modo tan genérico: "materiales silíceos o silíceos y aluminosos, que por sí mismos no poseen valor cementante alguno, pero que finamente divididos y en presencia de humedad, reaccionarán químicamente con hidróxido de calcio a temperaturas ordinarias para formar compuestos que poseen propiedades cementantes". Por consiguiente y de acuerdo con todo lo anterior, el objetivo primordial de esta Tesis Doctoral ha sido: Diseñar y poner a punto un nuevo método analítico de utilidad técnica (que la duración máxima del ensayo no sea mayor de 28 días), para determinar el contenido de alúmina reactiva, vítrea o amorfa, Al2O3r-, de las puzolanas naturales y artificiales. Y una vez puesto a punto, validarlo a nivel de su repetibilidad, de acuerdo con parámetros estadísticos apropiados, poniendo especial énfasis en los criterios de aceptación establecidos por la American Association of Official Analytical Chemists (AOAC). Y para conseguirlo, la innovación de esta investigación se ha basado en los siguientes fundamentos generales, a saber: - Toda la alúmina de cualquier puzolana natural o artificial, capaz de ser atacada, disuelta y lixiviada en 28 días, por la portlandita o por el hidróxido de calcio, Ca(OH)2, en medio acuoso, es considerada como alúmina reactiva, Al2O3r-. - Dicha fracción alumínica reactiva de la puzolana natural o artificial se tiene que encontrar, además, en el estado físico-químico de poder reaccionar químicamente también, en presencia de hidróxido de calcio, cloruro de sodio y agua, para originar monocloro¿aluminato de calcio hidratado, C3A·CaCl2·10H2O, o sal de Friedel. Además, dicho estado físico-químico de la puzolana ha de ser acorde con la definición de alúmina reactiva adoptada en esta investigación en razón de las prestaciones reales de durabilidad química que le puede llegar a conferir a los cementos de mezcla y a sus productos derivados, hormigones, morteros y pastas, que se fabriquen con la misma. - La originalidad de este nuevo método analítico, respecto a los demás métodos ya existentes, reside en que la cuantificación de dicha fracción alumínica reactiva de la puzolana natural o artificial, se realiza mediante cálculo estequiométrico, basándose, para ello, en dicha reacción química de formación de sal de Friedel precisamente, tras 28 días de hidratación básica-salina acelerada de la puzolana natural o artificial, habiéndose realizado, además, en esta investigación dicha determinación cuantitativa de la cantidad de sal de Friedel originada por cada puzolana, mediante dos técnicas analíticas instrumentales que fueron las siguientes: el análisis termogravimétrico (variante I ó I-I en su caso) y el método de Rietveld con la difracción de Rayos X en polvo (variante II). - La reacción química de formación de sal de Friedel tras 28 días de hidratación básica-salina acelerada de las puzolanas que se analicen, se optimizó para asegurar que el único compuesto químico de aluminio y cloro formado fuese sal de Friedel nada más (dosificando para ello en cantidad adecuada los reactivos químicos necesarios: Ca(OH)2, NaCl y agua destilada), manteniendo, además y por otra parte, el compromiso apropiado entre el máximo rendimiento de dicha reacción química (ataque, disolución y lixiviación en 28 días, de toda la alúmina reactiva de la puzolana) y el modo y medios más adecuados de acelerarlo para conseguirlo fue a 40°C de temperatura, con agitación constante y cierre hermético del reactor. - La aplicabilidad y selectividad del nuevo método analítico, objeto de esta Tesis Doctoral, fue estudiada con una serie de puzolanas naturales y artificiales españolas, silíceas y/o silíceas y aluminosas en naturaleza, que fueron las siguientes: M0 (metacaolín 0), M1 (M0 con 50 % de cuarzo), C y L (puzolanas naturales de las Islas Canarias), CV10 y CV17 (cenizas volantes), A (puzolana natural de Almagro), O (puzolana natural de Olot) y HS (humo de sílice). - Todas las adiciones minerales anteriores cumplieron con los principales requisitos físicos y químicos que son preceptivos para poder considerarlas, antes de todo, como puzolanas, lo que era indispensable y de obligado cumplimiento, para poderles determinar su contenido total de Al2O3r- (%) mediante el nuevo método analítico. Estos condicionantes fueron los siguientes: grado adecuado de finura de molido o tamaño medio de partícula (según la norma EN 451-2), haber sido analizadas químicamente antes de todo (según la norma EN 196-2 ó la ASTM C311), con el fin de determinarles especialmente, sus contenidos totales de SiO2 (%), Al2O3 (%) y Fe2O3 (%), haberles determinado, además, su contenido de sílice reactiva, SiO2r- (%) (según la norma UNE 80225), y haber cumplido con el ensayo de puzolanicidad o de Frattini (según la norma EN 196-5) a la edad de 28 días al menos. Este último requisito, otrora de obligado cumplimiento hasta el año 1988, para cualquier puzolana natural y artificial que una fábrica de cementos pretendiera introducir en el proceso de fabricación de un nuevo cemento puzolánico o cemento tipo CEM IV, ha logrado así, que se tenga que volver utilizar de nuevo de forma obligada con esta Tesis Doctoral. Y los resultados obtenidos con el nuevo método analítico de los contenidos de Al2O3r-(%) de las puzolanas seleccionadas, fueron los siguientes: - Mediante su variante I: M0 29.9 %, M1 16.9 %, CV10 11.4 %, L 12.3 %, C 12.6 %, A 8.0 %, CV17 9.5 % y O 6.3 % de Al2O3r-, y - Mediante su variante II: M0 30.7 %, M1 15.4 %, CV10 14.7%, L 11.8 %, C 11.1 %, A 8.9 %, CV17 9.6 % y O 6.8 % de Al2O3r-. Finalmente, todos ellos fueron contrastados, además, mediante la calibración y validación del nuevo método analítico, con los valores de referencia obtenidos de esas mismas puzolanas, los cuales se les habían determinado mediante el método de Florentín, consistente en atacar, disolver y lixiviar también toda la fracción alumínica soluble de la puzolana (y además, aquella silícica y férrica que la constituyen a la par), pero, en especial, su contenido total de alúmina reactiva, mediante un ataque básico (con Ca(OH)2 en medio acuoso a temperatura del laboratorio, habiendo sido, además, su duración hasta 1 año), seguido de otro ácido (con HCl, d = 1.12), habiéndose obtenido esta vez los siguientes resultados de sus contenidos de Al2O3r- (%): M0 28.8 %, M1 16.7 %, CV10 9.7 %, L 11.2 %, C 12.2 %, A 13.0 %, CV17 10.6 % y O 9.5 %. Dicha validación realizada ha puesto de manifiesto, en términos generales, que el nuevo método analítico es más fidedigno que el de Florentín, por lo que resulta ser totalmente apropiado para obtener los resultados que se han pretendido, además de proporcionarlos en un espacio de tiempo relativamente corto (28 días a lo sumo) y a un coste económico razonable por no elevado (salvo error u omisión y libre de impuestos directos e indirectos, el coste económico estimado de la variante I estaría en torno a 800.00 - 900.00 €/puzolana -caso más probable-, y aproximadamente una tercera parte nada más, en el caso de que la edad máxima del ensayo acelerado sea 7 días nada más -caso menos probable-), y, por consiguiente, técnicamente aceptable, al cumplir, además, en todo el rango considerado de variabilidad posible de concentraciones o contenidos del analito buscado en la puzolana, con tales parámetros de validación como son: linealidad (los resultados obtenidos son directamente proporcionales a la señal-respuesta instrumental recibida), sensibilidad, precisión excelente, repetibilidad satisfactoria de los valores obtenidos de los contenidos de Al2O3r- de todas y cada una de las adiciones puzolánicas seleccionadas, confirmando, por ello, la universalidad de su uso. Finalmente, las ventajas del nuevo método analítico, respecto a los métodos ya existentes recopilados de la bibliografía (el método de Florentín, el método de López Ruiz -HF 40 % y HNO3 2N-, el método de Murat y Driouche para arcillas -HF 0.5M-, el método de Arjuan, Silbee y Roy para cenizas volantes -HF 1 %- y su modificación por Fernández-Jiménez y cols. -HF 1 %, 27Al NMR MAS y XRD (método de Rietveld)-, y el método de determinación de la relación SiO2r-/Al2O3r- para arcillas y cenizas volantes por Ruiz-Santaquiteria y cols. -HF 1 %, NaOH 8M y ICP-AES-) son, principalmente, estar exento de peligro alguno para la seguridad vital de las personas que lo tengan que manipular y poner en práctica, ser bastante apropiado para control de calidad además de para investigación, su considerable menor coste económico, su relativamente corto espacio de tiempo que se necesita para obtener la respuesta-resultado pretendida (28 días a lo sumo), así como su universalidad y selectividad, puesto que además, su aplicabilidad es para todo tipo de adiciones puzolánicas naturales o artificiales, como así lo demuestran los resultados obtenidos de los materiales puzolánicos naturales y artificiales seleccionados y analizados, en un rango de concentraciones del analito -contenido de alúmina reactiva, Al2O3r- (%)-, desde el 5 % hasta el 30 % en masa, rango éste que, por otra parte, comprende prácticamente TODAS las adiciones puzolanas naturales y artificiales existentes en el mercado transnacional y las aún por existir. Por consiguiente y de acuerdo con lo anterior, el nuevo método analítico, ya sea realizado mediante su variante I o la II, debido, - en primer lugar, a los fundamentados planteamientos relativos a su procedimiento experimental -modus operandi- el cual ha sido aplicado a una amplia gama de puzolanas naturales y artificiales, y - en segundo lugar, debido a la calidad de los resultados obtenidos con un grado de precisión y repetibilidad excelentes, ha demostrado poseer una gran utilidad científica -para investigación-, pero, sobre todo, técnica -para control de calidad de adiciones puzolánicas naturales y artificiales que se adicionan habitualmente al cemento Portland en fábrica y/o a sus hormigones y morteros en planta-, además de ser representativos los valores obtenidos mediante el mismo respecto a la más que probable durabilidad química que cada una de ellas puede llegarle a conferir al hormigón armado y en masa, mortero y pasta del que forme parte, así como también su cantidad adecuada de sustitución parcial de cada cemento Portland para conseguirla, acorde con sus propias prestaciones químico-físicas o físico-químicas que puede llegarle a conferir, según sea su carácter químico (alumínico, alumínico-silícico, silícico-alumínico, silícico-férrico-alumínico o silícico), forma y tamaño medio de su partícula. Por último, el nuevo método analítico ha demostrado cumplir además, con todos los requisitos de obligado cumplimiento que establece la norma ISO/IEC 17025 sobre la calidad y fiabilidad de nuevos métodos o procedimientos analíticos no normalizados todavía, para poder ser propuesto en un futuro próximo, ante la Comisión de AENOR correspondiente, con objeto de comenzar un expediente para su certificación y normalización. ________________________________________________________________________________ Both the subject of this research, its objectives, fundamentals, materials selected and experimental part to achieve, have all been promoted by the situation and the state of reinforced concrete constructions that began performing in Spain from 1975, with concrete and mortars cement containing fly ash up to 20 %, in principle, and later, up to 35 % to its content of Portland cement, which and against expected, demanded a need to improve their performance, especially due to an unexpectedly low level of durability of some works built with them, despite, however, its apparent benefits of all kinds are ascribed to them. Ultimately, the natural or artificial pozzolanic additions, such as fly ash specially, referred to above, have been used with regulation to manufacture cements and/or its derivatives, concretes, mortars, cement pastes, in the most industrialized countries. More than three decades ago, under the same conditions and identical construction mainly uses concretes and mortars plain Portland cement, besides coming, given that use of these waste materials, industrial by-products today for environmental and/or economic issues. For this reason, this Doctoral Thesis aims to answer properly and schematically (in the form of flow chart), the criteria to be taken into account when selection and characterization standardized for these active mineral additions, especially prior to choosing and use in the so-called Portland Cement (PC) pozzolan, or with fly ash or with calcined shales or with calcined pozzolans or with silica fume or PC mixed or pozzolanic cement or compound cement, for that such pathology problems will not occur when reinforced concretes nor mass concretes are used for building. Hence the very particular and special focus about this research, having confined only to the natural or artificial pozzolans, considering them all, regardless of their origin, approach as materials consisting of small crystalline fractions randomly distributed in a largely vitreous and/or amorphous matrix, which confers their reactivity with calcium hydroxide in the form of slaked lime or portlandite from PC. In turn, these vitreous and/or amorphous fractions consist in its greater part, by reactive silica, SiO2r-, reactive alumina, Al2O3r-, and reactive iron oxide, Fe2O3r-, which also receive, in conjunction, the specific name of "hydraulic factors" of the pozzolan. Usually, they all differs in quantity of their respective total contents of the SiO2 (%), Al2O3 (%) and Fe2O3 (%) determined the pozzolan by alkaline fusion by means of standard procedures. Of the three above-mentioned oxides reagents and from the technical point of view, the most important for its increased presence in every one of the natural or artificial pozzolans and also significance in the chemical durability that can get them to give the concrete mortar or cement paste which contain them, are SiO2r- and Al2O3r-. From the first two, the SiO2r- reacts with portlandite only, released in the hydration of the PC (and with Ca(OH)2), to form C-S-H gels, transformed in tobermorites or jennites later on, similar to C-S-H gels also originating from the alite and belite hydration in the CP. From the standardization criteria point of view, the presence of this silicic fraction in pozzolans is regulated at first, by the European standard EN 197-1, in general, also being referred by the EN 450-1:2006, in the context of the fly ash in addition to the concrete, as a "fine powder of spherical particles mainly crystalline form. It is from the combustion of pulverized coal, which have pozzolanic properties and is mainly composed of SiO2 and Al2O3". In addition and according to the EN 197-1 standard, the reactive silica content (which can be defined and determined in accordance with EN 197-1 standard or its UNE 80225 standard) must not be lower than 25 % of its mass. Meanwhile, considerable experimental studies by Talero and Talero et al, have shown that if the pozzolan is not adequate in quality nor quantity, the durability of cement that is part and, therefore, of its derivative products, concretes, mortars and pastes cement, can become abnormally low because its reactive alumina, Al2O3r- (%), content or tetra- or penta-coordinated alumina which involves itself in a very direct and totally mixed and conflicting results even at all aggressive chemical attack natural to produce to the concrete, mortar and paste with inadequate natural and/or artificial pozzolans, such as those from the selenitous land and waters (sulfates, strikes if the material itself concrete, mortar and paste that contain them, for rapid forming ettringite form, ett-rf, which can even cause rapid gypsum attack to said concrete). In contrast, sea spray and de-icing salts (chlorides strikes the reinforced steel concrete causing them electrochemical corrosion by "bite", although in that other chemical attack, such Al2O3r- causes rapid Friedel's salt formation, Fs-rf, too, to cause protector effect of the electrochemical corrosion of reinforcements for these chlorides), seawater (mutual aggressive action of chlorides and sulfates), carbonation, alkali-silica reaction, and, in addition, to influence the release of hydration heat, as well as in the rheological behavior of the pastes, etc., decreasing/shorting them thus their expected durability and sometimes even very seriously. But the most ironic thing is, that despite its referral totally opposed, compared to sulfates and chlorides, behaviour, - far not available is, a chemical analysis method for its quantitative determination, which is also relatively simple in operation, accurate, precise, rapid response, from a technical point of view for building (no more than 28 days), repeatable, reproducible, not involving danger to life safety of the people who need to manipulate and implement, economic, and also serve for both scientific research and technical side, and - has yet to be any chemical specification that sets maximum levels for Al2O3r-(%) in the natural or artificial pozzolan to be added to the cement and/or to the concrete that will be subject to a particularly aggressive chemical attack from those mentioned above, and in particular, to sulphates, chlorides or sea water. And for the sake of and justification of this need, it has to be said that the current Spanish Instruction for Structural Concrete EHE-08 does not provide any specification on "hydraulic factors" in general, nor the content of Al2O3r- (%) in fly ash, very particular, as Article 30º "Additions", or any other Article, although does provide, however, other chemical specifications lacking the necessary meaning in terms of the message Chemical Durability mentioned, nor the Article 37º which and for greater sake, is paradoxically entitled "Durability of the concrete and of their reinforcements". It has also not contemplated in the latest version just released from EN 197-1 standard entitled "Cement Part 1: Composition, specifications and conformity criteria for common cements". Nor, in EN 450-1:2006 entitled "Fly ash for concrete Part 1: Definitions, specifications and conformity criteria", nor by current Spanish Instruction for Cement Reception, RC-08, nor the ASTM C618-03 Standard either. The only chemical specification that both Standards, European and American, refer is one that says that the sum of the total contents of SiO2 (%), Al2O3 (%) and Fe2O3 (%) of natural and artificial pozzolan, must be greater than or equal to 70 % , defining pozzolans thus: "siliceous or aluminous and siliceous materials, which themselves do not have any cementitious value but finely divided and in the presence of moisture it reacts with calcium hydroxide at ordinary temperatures to form compounds possessing cementitious properties". Consequently and according to everything related before, the primary objective of this Doctoral Thesis has been: To design and start-up a new quantitative analytical method of technical utility (the maximum test duration is not more than 28 days), to determine the content of reactive alumina content, Al2O3r- (%), vitreous or amorphous alumina, of natural and artificial pozzolans. And once designed, validate at repeatability level and in accordance with appropriate statistical parameters with special emphasis on the acceptance criteria established by the American Association of Official Analytical Chemists (AOAC). And to achieve this, the innovation of this research has been based on the following general principles, namely: - All the alumina in any pozzolan, natural or artificial, that can be attacked, dissolved and leached by portlandite or calcium hydroxide, Ca(OH)2, in aqueous medium, is considered reactive alumina, Al2O3r-. - This aluminic fraction of natural or artificial pozzolan to analyze and study, has to be in such physical-chemical state that it can react in the presence of calcium hydroxide, sodium chloride and water status and to cause monochloro-aluminate hydrated calcium, C3A·CaCl2·10H2O or Friedel's salt. Moreover, such physical-chemical state of the pozzolan must be consistent with the definition of reactive alumina adopted in this research because of the actual performance of chemical durability that can reach confer on blended cements and their derivatives, concretes, mortars and pastes that are manufactured with the same. - The originality of this new analytical method, compared to the other methods for determining reactive alumina existing (collected in abbreviated form in the state of the art of this report), is the quantification of such aluminic fraction of natural or artificial pozzolans is performed by stoichiometric calculation based on this, in the chemical reaction of Friedel's salt formation after 28 days of the analysis of saline-basic hydration accelerated natural or artificial pozzolan also performed in this research, and the quantitative determination of the Friedel's salt has been performed by two instrumental analytical techniques known as thermogravimetric analysis (variant I), and Rietveld method with X-ray powder diffraction (variant II). - The chemical reaction of Friedel's salt formation after 28 days of accelerated saline-basic hydration of the selected natural and artificial pozzolan, was optimized to ensure that the single chemical compound of aluminium and chlorine formed was Friedel's salt only (dosing for this purpose in amount suitable chemical reagents: Ca(OH)2, NaCl and distilled water), and, on the other hand, maintaining the appropriate compromise between the highest yield from the chemical reaction (attack, dissolution and leaching in 28 days, all reactive alumina of pozzolan) and to accelerate the etching media, which were 40°C temperature, constant stirring and sealing the reactor. - The applicability and selectivity of the new analytical method, the subject of this Doctoral Thesis, was studied with a series of Spanish natural and artificial pozzolans, siliceous or siliceous and aluminous in nature, which were as follows: M0 (metakaolin 0), M1 (M0 with 50 % quartz), L and C (natural pozzolans of the Canary Islands), CV10 (fly ash 10), CV17 (fly ash 17), A (natural pozzolan of Almagro), O (natural pozzolan of Olot), and HS (silica fume). - All mineral admixtures were selected satisfied the physical and chemical requirements proposed to consider them as pozzolan, which was mandatory, so its Al2O3r- (%) content can determine by the new analytical method. These conditions were as follows: adequate degree of fineness of grind or average particle size (according to EN 451-2 standard), have been analyzed chemically (according to EN 196-2 or ASTM C311 standards), in order to determine their total contents of SiO2 (%), Al2O3 (%) and Fe2O3 (%), mainly, having also determined its reactive silica content, SiO2r- (%) (UNE 80225 standard), and fulfilled with testing of pozzolanicity or Frattini test (according to EN 196-5 standard) at 28 days age at least. The last criteria was mandatory until 1988, for any natural and artificial pozzolan to a factory intended to introduce cements in the manufacturing process of a new Portland cement type CEM IV pozzolanic additions, and with this Doctoral Thesis has made is to be used once again mandatory. And the results obtained using the new analytical method, of the Al2O3r- (%) content for each selected pozzolan, were as follows: - by its variant I: M0 29.9 % , M1 16.9 % , CV10 11.4 % , L 12.3 % , C 12.6 % , A 8.0 % , CV17 9.5 % and O 6.3 % of Al2O3r-, and - by its variant II: M0 30.7 % , M1 15.4 % , CV10 14.7% % , L 11.8 % , C 11.1 % , A 8.9 % , CV17 9.6 % and O 6.8 % of Al2O3r-. Finally, they would all be further contrasted by the calibration and validation of new analytical method, with reference values obtained from these same natural and artificial pozzolans, which had been given by the method of Florentin, consisting of attack, dissolve and leached with a basic attack (with Ca(OH)2 in aqueous medium and laboratory temperature, having also been its duration up to 1 year), followed by another acid attack (HCl, d = 1.12), all soluble aluminic fraction of pozzolan, and in particular their total content of reactive alumina, Al2O3r-(%), was this time as follows: M0 28.8 %, M1 16.7 %, CV10 9.7 %, L 11.2 %, C 12.2 %, A 13.0 %, CV17 10.6 % and O 9.5 % (and their siliceous and iron contents that are at par). This validation has shown on the new analytical method is more reliable than Florentin method, so it turns out to be entirely appropriate to get the results that have been tried by the same, besides providing them a relatively short space of time (28 days at most) and reasonably no high economic cost (unless mistake -free direct and indirect taxes, such economic cost would be between 800.00 - 900.00 €/pozzolan (most likely case), and about an one-third part around, in the event that the maximum age of the accelerated test is 7 days only (less likely case). So it is technically acceptable, to consider the range of possible variability of concentrations or contents pozzolan analyte with validation parameters such as: linearity (the results obtained are directly proportional to the instrumental response signal received), excellent sensitivity and accuracy, satisfactory repeatability values from the contents of each and Al2O3r- (%) each selected pozzolan, confirming therefore universal use. Finally, the advantages of the new analytical method over existing methods compiled from literature (Florentin method , the Lopez Ruiz method -HF and HNO3 40 % 2N-, the method of Murat and Driouche for clays -0.5M HF-, the method of Arjuan, Roy and Silbee for fly ash -HF 1 %- and its modification by Fernández-Jiménez et al -HF 1 %, 27Al MAS NMR and XRD (Rietveld method)-, and the method for determining the SiO2r-/Al2O3r- clay and fly ash ratio of Santaquiteria Ruiz et al -HF 1 %, NaOH 8M and ICP-AES-) are primarily and relatively short time get the result intended answer (28 days at most), its considerable lower cost, free from danger to the life safety of the people who need to manipulate and put in practice as well as its universality and selectivity, since it is applicable for all types of natural or artificial pozzolans, as it has been shown by the results of selected natural and artificial pozzolanic materials and analyzed in a range of analyte concentrations -reactive alumina, Al2O3r- (%) content- from 5 % to 30 % by mass, this range, on the other hand, includes virtually ALL existing transnational market in natural and artificial pozzolans and still exist. Therefore and in accordance with the above, the new analytical method is already performed by the variant I or II, because, - firstly, grounded to experimental approaches concerning its experimental procedure -"modus operandi"- which has been applied to a wide range of natural and artificial pozzolans, and - secondly, due to the quality of the results obtained with a great degree of accuracy and repeatability, it has been shown to possess significant scientific value in the research, but especially technical value -for quality control of natural and artificial pozzolans commonly added to Portland cement factory and/or directly to their concrete and mortar in plant-, and also be representative enough of the values obtained by the same probable chemical durability that each of them can reach out to give the concrete mortar and paste to which it belongs, as well as proper amount of partial replacement of Portland cement. To get in line with their own chemical-physical or physical-chemical features which can come to confer, as its chemical character (aluminic, silicic-aluminic, aluminic-silicic, aluminic-ferric-silicic or ferric-silicic), form and medium size of its particle is. Finally, the new analytical method has proven to meet all mandatory requirements established by ISO/IEC 17025 on the quality and reliability of new methods or analytical procedures are not standardized yet, in order to be considered appropriate this new analytical method, in this Doctoral Thesis it is to be proposed in the near future, before the corresponding AENOR (Spanish Association for Standardization and Certification) Commission, to start a procedure for certification and standardization.

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Este documento es una guía para el desarrollo de una aplicación para dispositivos móviles en Android. Dicha aplicación combina las técnicas de visión por computador para calibrar la cámara del dispositivo y localizar un elemento en el espacio en base a esos los parámetros calculados en la calibración. El diseño de la aplicación incluye las decisiones sobre la forma en que se reciben los inputs de la aplicación, que patrones se utilizan en la calibración y en la localización y como se muestran los resultados finales al usuario. También incluye un diagrama de flujo de información que representa el tránsito de esta entre los diferentes módulos. La implementación comienza con la configuración de un entorno para desarrollar aplicaciones con parte nativa en Android, después comenta el código de la aplicación paso por paso incluyendo comentarios sobre los archivos adicionales necesarios para la compilación y finalmente detalla los archivos dedicados a la interfaz. Los experimentos incluyen una breve descripción sobre cómo interpretar los resultados seguidos de una serie de imágenes tomadas de la aplicación con diferentes localizaciones del patrón. En la entrega se incluye también un video. En el capítulo de resultados y conclusiones podemos encontrar observaciones sobre el desarrollo de la práctica, opiniones sobre su utilidad, y posibles mejoras.---ABSTRACT---This document is a guide that describes the development of and application for mobile devices in Android OS. The application combines computer vision techniques to calibrate the device camera and locate an element in the real world based on the parameters of the calibration The design of the application includes the decisions over the way that the application receives its input data, the patterns used in the calibration and localization and how the results are shown to the user. It also includes a flow chart that describes how the information travels along the application modules. The development begins with the steps necessary to configure the environment to develop native Android applications, then it explains the code step by step, including commentaries on the additional files necessary to build the application and details the files of the user interface. The experiments chapter explains the way the results are shown in the experiments before showing samples of different pattern localizations. There is also a video attached. In the conclusions chapter we can find observations on the development of the TFG, opinions about its usefulness, and possibilities of improvement in the future.

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La seguridad y fiabilidad de los procesos industriales son la principal preocupación de los ingenieros encargados de las plantas industriales. Por lo tanto, desde un punto de vista económico, el objetivo principal es reducir el costo del mantenimiento, el tiempo de inactividad y las pérdidas causadas por los fallos. Por otra parte, la seguridad de los operadores, que afecta a los aspectos sociales y económicos, es el factor más relevante a considerar en cualquier sistema Debido a esto, el diagnóstico de fallos se ha convertido en un foco importante de interés para los investigadores de todo el mundo e ingenieros en la industria. Los principales trabajos enfocados en detección de fallos se basan en modelos de los procesos. Existen diferentes técnicas para el modelado de procesos industriales tales como máquinas de estado, árboles de decisión y Redes de Petri (RdP). Por lo tanto, esta tesis se centra en el modelado de procesos utilizando redes de petri interpretadas. Redes de Petri es una herramienta usada en el modelado gráfico y matemático con la habilidad para describir información de los sistemas de una manera concurrente, paralela, asincrona, distribuida y no determinística o estocástica. RdP son también una herramienta de comunicación visual gráfica útil como lo son las cartas de flujo o diagramas de bloques. Adicionalmente, las marcas de las RdP simulan la dinámica y concurrencia de los sistemas. Finalmente, ellas tienen la capacidad de definir ecuaciones de estado específicas, ecuaciones algebraicas y otros modelos que representan el comportamiento común de los sistemas. Entre los diferentes tipos de redes de petri (Interpretadas, Coloreadas, etc.), este trabajo de investigación trata con redes de petri interpretadas principalmente debido a características tales como sincronización, lugares temporizados, aparte de su capacidad para procesamiento de datos. Esta investigación comienza con el proceso para diseñar y construir el modelo y diagnosticador para detectar fallos definitivos, posteriormente, la dinámica temporal fue adicionada para detectar fallos intermitentes. Dos procesos industriales, concretamente un HVAC (Calefacción, Ventilación y Aire Acondicionado) y un Proceso de Envasado de Líquidos fueron usados como banco de pruebas para implementar la herramienta de diagnóstico de fallos (FD) creada. Finalmente, su capacidad de diagnóstico fue ampliada en orden a detectar fallos en sistemas híbridos. Finalmente, un pequeño helicóptero no tripulado fue elegido como ejemplo de sistema donde la seguridad es un desafío, y las técnicas de detección de fallos desarrolladas en esta tesis llevan a ser una herramienta valorada, desde que los accidentes de las aeronaves no tripuladas (UAVs) envuelven un alto costo económico y son la principal razón para introducir restricciones de volar sobre áreas pobladas. Así, este trabajo introduce un proceso sistemático para construir un Diagnosticador de Fallos del sistema mencionado basado en RdR Esta novedosa herramienta es capaz de detectar fallos definitivos e intermitentes. El trabajo realizado es discutido desde un punto de vista teórico y práctico. El procedimiento comienza con la división del sistema en subsistemas para seguido integrar en una RdP diagnosticadora global que es capaz de monitorear el sistema completo y mostrar las variables críticas al operador en orden a determinar la salud del UAV, para de esta manera prevenir accidentes. Un Sistema de Adquisición de Datos (DAQ) ha sido también diseñado para recoger datos durante los vuelos y alimentar la RdP diagnosticadora. Vuelos reales realizados bajo condiciones normales y de fallo han sido requeridos para llevar a cabo la configuración del diagnosticador y verificar su comportamiento. Vale la pena señalar que un alto riesgo fue asumido en la generación de fallos durante los vuelos, a pesar de eso esto permitió recoger datos básicos para desarrollar el diagnóstico de fallos, técnicas de aislamiento, protocolos de mantenimiento, modelos de comportamiento, etc. Finalmente, un resumen de la validación de resultados obtenidos durante las pruebas de vuelo es también incluido. Un extensivo uso de esta herramienta mejorará los protocolos de mantenimiento para UAVs (especialmente helicópteros) y permite establecer recomendaciones en regulaciones. El uso del diagnosticador usando redes de petri es considerado un novedoso enfoque. ABSTRACT Safety and reliability of industrial processes are the main concern of the engineers in charge of industrial plants. Thus, from an economic point of view, the main goal is to reduce the maintenance downtime cost and the losses caused by failures. Moreover, the safety of the operators, which affects to social and economic aspects, is the most relevant factor to consider in any system. Due to this, fault diagnosis has become a relevant focus of interest for worldwide researchers and engineers in the industry. The main works focused on failure detection are based on models of the processes. There are different techniques for modelling industrial processes such as state machines, decision trees and Petri Nets (PN). Thus, this Thesis is focused on modelling processes by using Interpreted Petri Nets. Petri Nets is a tool used in the graphic and mathematical modelling with ability to describe information of the systems in a concurrent, parallel, asynchronous, distributed and not deterministic or stochastic manner. PNs are also useful graphical visual communication tools as flow chart or block diagram. Additionally, the marks of the PN simulate the dynamics and concurrence of the systems. Finally, they are able to define specific state equations, algebraic equations and other models that represent the common behaviour of systems. Among the different types of PN (Interpreted, Coloured, etc.), this research work deals with the interpreted Petri Nets mainly due to features such as synchronization capabilities, timed places, apart from their capability for processing data. This Research begins with the process for designing and building the model and diagnoser to detect permanent faults, subsequently, the temporal dynamic was added for detecting intermittent faults. Two industrial processes, namely HVAC (Heating, Ventilation and Air Condition) and Liquids Packaging Process were used as testbed for implementing the Fault Diagnosis (FD) tool created. Finally, its diagnostic capability was enhanced in order to detect faults in hybrid systems. Finally, a small unmanned helicopter was chosen as example of system where safety is a challenge and fault detection techniques developed in this Thesis turn out to be a valuable tool since UAVs accidents involve high economic cost and are the main reason for setting restrictions to fly over populated areas. Thus, this work introduces a systematic process for building a Fault Diagnoser of the mentioned system based on Petri Nets. This novel tool is able to detect both intermittent and permanent faults. The work carried out is discussed from theoretical and practical point of view. The procedure begins with a division of the system into subsystems for further integration into a global PN diagnoser that is able to monitor the whole system and show critical variables to the operator in order to determine the UAV health, preventing accidents in this manner. A Data Acquisition System (DAQ) has been also designed for collecting data during the flights and feed PN Diagnoser. Real flights carried out under nominal and failure conditions have been required to perform the diagnoser setup and verify its performance. It is worth noting that a high risk was assumed in the generation of faults during the flights, nevertheless this allowed collecting basic data so as to develop fault diagnosis, isolations techniques, maintenance protocols, behaviour models, etc. Finally, a summary of the validation results obtained during real flight tests is also included. An extensive use of this tool will improve preventive maintenance protocols for UAVs (especially helicopters) and allow establishing recommendations in regulations. The use of the diagnoser by using Petri Nets is considered as novel approach.

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The current annual arisings of used car/van tyres in the U.K. has been found to be around 25m (188,000 tonnes). After the established reuse industries have taken their requirements this leaves 13.5m (102,000 tonnes) waste tyres; a quantity that can no longer be satisfactorily tipped. Laboratory scale experiments have shown that tyre can be pyrolised, using a molten carbonate system as the reaction medium, at rates corresponding to 14.9-42.7 g tyre/min. per litre of melt over the range 475 and 650°C. The product yields by weight of tyre input between the same temperatures are: hydrocarbon oil 23-36 wt. %, hydrocarbon gas 7- 18 wt. %, carbonaceous char 35-40 wt. %, steel 16.7 wt. % and inorganics 5.4 wt. %. The oil and gas evolve from the reactor and can easily be collected by conventional means. The steel and inorganics remain in the reactor although on the commercial scale it is proposed that they would be removed by physical and chemical methods respectively. The char was found to pose considerable handling problems and so a method was devised by which it could be gasified in the reactor. This was best achieved by passing air at a less than stoichiometric rate which gave a gaseous product rich in carbon monoxide. In addition this action provides heat for the system as a whole. The rates at 675-9000C were in the range corresponding to 5.6- 14.89 char/min. per litre of melt. A process flow chart has been proposed for a continuous operation based on these systems. Data from theoretical and experimental studies has enabled economic evaluations of several commercial scales to be carried out. These have shown that 4,000 and 10,000 t/yr operations show a DCF rate of return around 30% while a 50,000 t/yr operation shows 60% which would be attractive to an experienced scrap operator.

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Construction projects are risky. A build-operate-transfer (BOT) project is recognised as one of the most risky project schemes. This scheme has been employed rather frequently in the past few decades, in both developed and developing countries. However, because of its risky nature, there have been failures as well as successes. Risk analysis in an appropriate way is desirable in implementing BOT projects. There are various tools and techniques applicable to risk analysis. The application of these risk analysis tools and techniques (RATTs) to BOT projects depends on an understanding of the contents and contexts of BOT projects, together with a thorough understanding of RATTs. This paper studies key points in their applications through reviews of relevant literatures and discusses the application of RATTs to BOT projects. The application to BOT projects is considered from the viewpoints of the major project participants, i.e. government, lenders and project companies. Discussion is also made with regard to political risks, which are very important in BOT projects. A flow chart has been introduced to select an appropriate tool for risk management in BOT projects. This study contributes to the establishment of a framework for systematic risk management in BOT projects.

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The research was carried out in the Aviation Division of Dunlop Limited and was initiated as a search for more diverse uses for carbon/carbon composites. An assumed communication model of adoption was refined by introducing the concept of a two way search after making cross industry comparisons of supplier and consumer behaviour. This research has examined methods of searching for new uses for advanced technology materials. Two broad approaches were adopted. First, a case history approach investigated materials that had been in a similar oosition to carbon/carbon to see how other material producing firms had tackled the problem. Second, a questionnaire survey among industrialists examined: the role and identity of material decision makers in different sized firms; the effectiveness of various information sources and channels; and the material adoption habits of different industries. The effectiveness of selected information channels was further studied by monitoring the response to publicity given to carbon/carbon. A flow chart has been developed from the results of this research which should help any material producing firm that is contemplating the introduction of a new material to the world market. Further benefit to our understanding of the innovation and adoption of new materials would accrue from work in the followino areas: "micro" type case histories; understanding more fully the role of product champions or promoters; investigating the phase difference between incremental and radical type innovations for materials; examining the relationship between the adoption rate of new materials and the advance of technology; studying the development of cost per unit function methods for material selection; and reviewing the benefits that economy of scale studies can have on material developments. These are all suggested areas for further work.

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The operation state of photovoltaic Module Integrated Converter (MIC) is subjected to change due to different source and load conditions, while state-swap is usually implemented with flow chart based sequential controller in the past research. In this paper, the signatures for different operational states are evaluated and investigated, which lead to an effective control integrated finite state machine (CIFSM), providing real-time state-swap as fast as the local control loop. The proposed CIFSM is implemented digitally for a boost type MIC prototype and tested under a variety of load and source conditions. The test results prove the effectiveness of the proposed CIFSM design.

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In August, 1994, the Office of Local Systems, Project Development Division, Iowa Department of Transportation established a Quality Improvement Team to review and improve upon the federal-aid project development process. The mission was to communicate federal-aid project development procedures to local agencies, beginning with the approval of the Statewide Transportation Improvement Program (STIP) and ending with obligation of federal funds by the Federal Highway Administration (FHWA). In January 1997, another Team (Make it Better) began meeting to clarify, update, and streamline the federal-aid project process. This Project Development Packet is a compilation of these efforts. The packet includes Project Development timelines, flow charts, guidelines, design criteria, Instructional Memorandums and forms to assist in the federal-aid project development process. The main (fold out) flow chart directs to other sections of the packet when appropriate.

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This flow chart shows the steps to go through to obtain a construction permit from DHEC.

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This flow chart shows the steps to go through to obtain a construction or environmental permit from DHEC.

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This flow chart shows the steps to go through to obtain a construction and environmental permit from DHEC.