Remote Laser-Induced Breakdown Spectroscopy in Underwater Archaeology: Identification of Chemical Fingerprints in Shipwrecks

Nowadays, one of the most important areas of interest in archeology is the characterization of the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged materials is an extremely valuable source of information on the origin and precedence of the wrecks, and also the raw materials employed during the manufacturing of the objects found in these sites. Sometimes extracting the archeological material from the marine environment is not practical due to the size of the sample, or is not permitted by the legislation or preservation practices. In these cases, the in-situ analysis turns into the only alternative. The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography 1. Advantages such as rapid and in situ analysis with no sample preparation make LIBS a suitable alternative for field measurements. A fiber-optics-based remote instrument has been designed for the recognition and identification of artworks in underwater archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS). The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variety of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). In this work, parametric studies in the laboratory such as gas flow pressure, beam focal conditions and angle of incidence, among others, were performed to optimize the best conditions for field analysis. Finally, results obtained in these field trials confirmed the capability of remote LIBS for in-situ analysis of underwater archeological samples.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Chemical Fingerprints in an Underwater Archaeological Shipwreck using a Remote Laser-Induced Breakdown Spectroscopy System

Nowadays, one of the most important areas of interest in archeology is the characterization of the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged materials is an extremely valuable source of information on the origin and precedence of the wrecks, and also the raw materials employed during the manufacturing of the objects found in these sites. Sometimes extracting the archeological material from the marine environment is not practical due to the size of the sample, or is not permitted by the legislation or preservation practices. In these cases, the in-situ analysis turns into the only alternative. The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography [1]. Advantages such as rapid and in situ analysis with no sample preparation make LIBS a suitable alternative for field measurements. A fiber-optics-based remote instrument has been designed for the recognition and identification of artworks in underwater archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multipulse excitation (MP-LIBS). The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variefy of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). In this work, parametric studies in the laboratory such as gas flow pressure, beam focal conditions and angle of incidence, among others, were performed to optimize the best conditions for field analysis. Finally, results obtained in these field trials confirmed the capability of remole LIBS for in-situ analysis of underwater archeological samples.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Libs in cultural heritage: recognition and identification of objects in an underwater archaeological shipwreck

Nowadays, one of the most important areas of interest in archeology is the characterization of the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged materials is an extremely valuable source of information on the origin and precedence of the wrecks, and also the raw materials employed during the manufacturing of the objects found in these sites. Nevertheless, sometimes it is not possible to extract the archaeological material from the marine environment due to size of the sample, the legislation or preservation purposes. In these cases, the in-situ analysis turns into the only alternative for obtaining information. In spite of this demand, no analytical techniques are available for the in-situ chemical characterization of underwater materials. The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography 1. Advantages such as rapid and in situ analysis with no sample preparation make LIBS a suitable alternative for field measurements. To further exploit the inherent advantages of the technology, a mobile fiber-based LIBS platform capable of performing remote measurements up to 50 meters range has been designed for the recognition and identification of artworks in underwater archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS) 2. The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variety of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). In the present work, the design and construction considerations of the instrument are reported and its performance is discussed on the basis of the spectral response, the remote irradiance achieved upon the range of analysis and its influence on plasma properties, as well as the effect of the laser pulse duration and purge gas to the LIBS signal. Also, to check the reliability and reproducibility of the instrument for field analysis several robustness tests were performed outside the lab. Finally, the capability of this instrument was successfully demonstrated in an underwater archaeological shipwreck (San Pedro de Alcántara, Malaga).Universidad de Málaga. Campus de Excelencia Internacional Andalucí

Sobre la equivalencia entre sucesiones con límite finito y sucesiones de Cauchy

Estudiamos, desde perspectivas simbólica y fenomenológica, diferencias y analogías existentes entre dos definiciones: la de límite finito de una sucesión y la de sucesión de Cauchy. Las diferencias entre una y otra definición parecen acentuarse en el aspecto fenomenológico, ya que observamos fenómenos distintos en cada una de ellas

Equivalencia fenomenológica entre fenómenos y equivalencia fenomenológica entre definiciones

Presentamos resultados relativos a la equivalencia matemática y fenomenológica de la definición de límite finito de una sucesión y la definición de sucesión de Cauchy. Para ello enunciamos dos criterios que permiten determinar cuando dos fenómenos son equivalentes y cuando lo son dos definiciones, desde un punto de vista fenomenológico. A continuación y usando estos resultados realizamos avances significativos para demostrar en un futuro próximo que la definición de límite finito de una función en el infinito y la condición de Bolzano-Cauchy, además de ser equivalentes matemáticamente también lo son fenomenológicamente. Para ello enunciamos los fenómenos organizados por la definición de Bolzano-Cauchy que convenimos en llamarla definición de función de Cauchy

Marco teórico y metodológico para el estudio del límite

Nuestras investigaciones dan cabida, con los mismos métodos, a diferentes nociones del límite, como límite finito de una sucesión o límite finito de una función en un punto. Consideramos tres elementos relacionados: fenomenología, sistemas de representación y pensamiento matemático avanzado. En la primera parte lo explicamos y presentamos ideas de otros marcos teóricos. Hemos usado las mismas herramientas metodológicas para descubrir y estudiar los fenómenos organizados por tres casos de límite finito y para reconocer esos fenómenos en libros de texto. Además, hemos desarrollado instrumentos para mostrar los fenómenos que emplean alumnos y profesores. En la segunda parte describimos los métodos usados para extraer información de libros de texto y alumnos

Fenómenos que organizan el límite

En este artículo se pone de manifiesto la presencia de los fenómenos de aproximación organizados por una definición de límite en el caso de las sucesiones de números reales y de las funciones reales de una variable real. La exposición incluye la caracterización de tales fenómenos, una descripción del análisis comparativo desarrollado en base a ellos entre dos definiciones formales de límite de sucesión y función, y una síntesis del estudio llevado a cabo sobre una muestra intencional de libros de texto de matemáticas

Maatalousyrittäjien tapaturmat Kiuruvedellä

Vuonna 2006 Kiuruvedellä sattui tapaturmia 13 %:lle viljelijöistä, kun koko Suomessa vastaava luku oli vain 7 %. Näin ollen Kiuruveden maatalousyrittäjille sattuu enemmän työtapaturmia kuin muualla Suomessa. Yleisimmät tapaturmatyypit ovat nyrjähdykset ja venähdykset, haavat sekä luunmurtumat. Tapaturmien riskitekijät luokitellaan fyysisiin ja teknisiin, biologisiin ja kemiallisiin riskitekijöihin. Miehille tapaturmia sattuu eniten konetöissä ja naisille karjanhoitotöissä. Maatalousyrittäjien työturvallisuutta tukevat monet eri toimet, kuten työterveyshuolto ja Mela. Tutkimus oli määrillinen ja strukturoitu kyselylomake lähetettiin kaikille Kiuruveden karjatiloille. Tutkimukseen vastasi 41,4 % maatalousyrittäjistä. Tutkimuksen tulokset käsiteltiin SPSS-tilastoohjelmalla ja esitettiin suorina jakaumina, ristiintaulukointina ja prosenttilukuina. Tutkimustuloksista ilmeni, että tapaturmia oli sattunut yhdestä kahteen kertaan 68,5 % vastaajista. Tutkimuksesta selvisi, että Kiuruvedellä tilakoot ovat keskimääräistä suuremmat, lypsykarjatiloja on paljon ja karjan koot ovat suuremmat. Nämä kaikki tekijät altistavat tapaturmille. Tapaturmatyypit tukivat aiempia tutkimustuloksia. Myös työvaiheet, missä tapaturmia sattui, olivat jakautuneet samoin kuin aiemmissa tutkimuksissa. Tutkimuksesta ilmeni että maatalousyrittäjät kokivat kiireen, väsymyksen ja poikkeavat tilanteet suurimmiksi tapaturmia aiheuttaviksi tekijöiksi. Opinnäytetyön tuloksien avulla Kiuruveden työterveyshuolto saa tietoa siitä, millaista tietoa maatalousyrittäjät tarvitsevat ja haluavat. Tulosten pohjalta työterveyshuolto pystyy myös paremmin ohjaamaan maatalousyrittäjiä tapaturmien ennaltaehkäisyyn.In year 2006 in Kiuruvesi occupational accidents happened to 13% of farmers, when in whole Finland corresponding figure was only 7 %. Consequently farmers in Kiuruvesi have more accidents than elsewhere in Finland. The most common types of accident are sprains, strains, wounds and fractures. Risk factors for accidents are classified as physical, technical, biological and chemical risk factors. With men the injuries occur mostly with machines at work and women in animal husbandry at work. Agricultural Entrepreneurs’ safety at work is supported by many different activities, such as Occupational Health Care and Mela, the Farmer’s Social Insurance Institution. The study was quantitative and a structured questionnaire was sent to all livestock farms in Kiuruvesi. The study was answered by 41.4 % of agricultural entrepreneurs. The results of the study were dealt with SPSS statistical software, and provided a breakdown of direct, cross tabulations and percentage figures. The results of the study showed that accidents had occurred between one and two times in 68.5 % of the respondents. The study showed that in Kiuruvesi farm sizes are larger than average, there are a lot of dairy farms with bigger livestock.. All of these factors endanger accidents. Types of accidents supported the earlier findings. Even phases where the accidents occurred were divided as at previous trials. The investigation revealed that the agricultural entrepreneurs considered the rush, fatigue and abnormal situations as major factors for accidents. With the help of the results of the Thesis the Occupational Health Care in Kiuruvesi gets information about the type of information farmers need and want. Based on the results the occupational health care is also better able to guide the agricultural entrepreneurs for prevention of accidents

Sucesión convergente y sucesión de Cauchy : equivalencia matemática y equivalencia fenomenológica

Esta investigación está enmarcada por la Fenomenología, el Pensamiento Matemático Avanzado y los Sistemas de Representación; en ella estudiamos una equivalencia fenomenológica, junto a la conocida equivalencia matemática, entre sucesión convergente y sucesión de Cauchy. Enunciamos dos fenómenos organizados por definiciones de límite finito de una sucesión y de sucesión de Cauchy; con el apoyo de libros de texto de secundaria, reconocemos en los libros de texto españoles dos fenómenos organizados por la primera definición mientras que, en los libros británicos, solamente observamos uno de los dos fenómenos. (Los libros de texto españoles se eligieron al azar y no constituyen muestras representativas. Los libros de texto británicos se eligieron "ad hoc" por lo que, evidentemente, tampoco constituyen muestras representativas.) Comparamos los fenómenos organizados por cada definición; establecemos analogías y diferencias entre ellos; introducimos un criterio de equivalencia entre fenómenos y un criterio de 'equivalencia fenomenológica' entre definiciones matemáticamente equivalentes; concluimos afirmativamente acerca de la equivalencia fenomenológica entre ambas definiciones. Ésta es algo más compleja que la equivalencia matemática, ya que involucra dos pares de fenómenos: un par se observa bajo un enfoque intuitivo mientras que el otro se observa bajo un enfoque formal. Este artículo prolonga resultados presentados en Claros (2010).This research is framed by Phenomenology, Mathematical Advanced Thinking and Representation Systems; we study a phenomenological equivalence to be added to the well known mathematical equivalence between a convergent sequence and a Cauchy sequence. We introduce two phenomena associated to each definition (the finite limit of a sequence, and a Cauchy sequence); by using several high school mathematics textbooks, we recognize, in Spanish high schools textbooks, two phenomena organized by the first definition and, in British high schools textbooks only one of these phenomena. (Spanish textbooks were randomly selected, but they are not a representative sample; British textbooks were selected by "ad hoc" criteria and do not should be considered as representing the corresponding population.) We compare phenomena organized by each definition; we establish analogies and differences among them; we introduce a criterion of equivalence between phenomena and a criterion of phenomenological equivalence between mathematically equivalent definitions; finally, we answer affirmatively about the phenomenological equivalence among both definitions. Phenomenological equivalence appears to be more complex than mathematical equivalence, since it involves two couples of phenomena: the first one is observed within an intuitive context while the other couple is observed within a formal context. This paper extends results presented in Claros (2010)