A study on mitigating the effect of sulphates in lime stabilised Cochin marine clays

Soft clays known for their high compressibility, low stiffness and low shear strength are always associated with large settlement. In place soil treatment using calcium-based stabilizers like lime and cement is a feasible solution to readdress strength deficiencies and problematic shrink/swell behaviour of unstable subgrade soils. Out of these, lime has been proved unambiguously as the most effective and economical stabilising agent for marine clays. Lime stabilisation creates long-term chemical changes in unstable clay soils to create strong, but flexible, permanent structural layers in foundations and other pavement systems. Even though calcium-based stabilizers can improve engineering properties of soft clays, problems can arise when they are used in soils rich in sulphates. It is possible for marine clays to be enriched with sulphates, either by nature or due to the discharge of nearby industrial wastes containing sulphates. The presence of sulphates is reported to adversely affect the cation exchange and pozzolanic reactions of cement and lime treated soil systems. The anions of sulphates may combine with the available calcium and alumina, and form insoluble ettringite in the soil system. Literature on sulphate attack in lime treated marine clays reports that formation of ettringite in lime-sodium sulphate-clay system is capable of adversely affecting the engineering behavior of marine clays. Only very few studies have been conducted on soft marine clays found along the coastal belt of Kerala and that too, is limited to Cochin marine clays. The studies conducted also have the limitation that the strength behaviour of lime stabilised clay was investigated only for one year. Practically no data pertaining to long term adverse effects likely to be brought about by sulphates on the strength and compressibility characteristics of Cochin marine clays is available. The overriding goal of this investigation was thus to examine the effectiveness of lime stabilisation in Cochin marine clays under varying sulphate contents. The study aims to reveal the changes brought about by varying sulphate contents on both physical and engineering properties of these clays stabilised by lime and the results for various curing periods up to two years is presented in this thesis. Quite often the load causing an unacceptable settlement may be less than the load required to cause shear failure and therefore attempt has been made in this research to highlight sulphate induced changes in both the compressibility and strength characteristics of lime treated Cochin marine clays. The study also aimed at comparing the available IS methods for sulphate quantification and has attempted to determine the threshold level of sulphate likely make these clays vulnerable by lime stabilisation. Clays used in this study were obtained from two different sites in Kochi and contained sulphate in two different concentrations viz., 0.5% and 0.1%. Two different lime percentages were tried out, 3% and 6%. Sulphate content was varied from 1% to 4% by addition of reagent grade sodium sulphate. The long term influence of naturally present sulphate is also investigated. X-ray diffraction studies and SEM studies have been undertaken to understand how the soil-lime reactions are affected in the presence of sodium sulphate. Natural sulphate content of 0.1% did not seem to have influenced normal soil lime reactions but 0.5% sulphate could induce significant changes adversely in both compressibility and strength behaviour of lime treated clays after long duration. Compressibility is seen to increase drastically with increasing sulphate content suggesting formation of ettringite on curing for longer periods. Increase in compression index and decrease in bond strength with curing period underlined the adverse effects induced in lime treated marine clays by the presence of sulphates. Presence of sulphate in concentrations ranging from 0.5 % to 4% is capable of adversely affecting the strength of lime treated marine clays. Considerable decrease is observed with increasing concentrations of sulphate. Ettringite formation due to domination of sodium ions in the system was confirmed in mineralogical studies made. Barium chloride and barium hydroxide is capable of bringing about beneficial changes both in compressibility and strength characteristics of lime treated Cochin marine clays in the presence of varying concentrations of sulphate and is strongly influenced by curing time. Clay containing sodium sulphate has increased strength values when either of barium compounds was used with lime ascompared with specimens treated with lime only. Barium hydroxide is observed to remarkably increase the strength as compared to barium chloride,when used in conjunction with lime to counteract the effect of sulphate.

Das professionelle Handlungswissen von DaZ-Lehrenden in der Erwachsenenbildung am Beispiel Binnendifferenzierung : eine qualitative Studie

Das Forschungsfeld der vorliegenden Arbeit sind die Deutsch als Zweitsprache-Kurse, die im Zeitraum der Untersuchung (2002) noch vom Sprachverband Deutsch (vormals: für ausländische Arbeitnehmer) unterstützt wurden. Da sich mit diesem wichtigen und breiten Anwendungsgebiet der Fremdsprachendidaktik bisher nur wenige Studien beschäftigt haben, ist als Forschungsansatz eine explorativ-qualitative Herangehensweise gewählt worden. Die Kurse für erwachsene Einwanderer zeichnen sich durch eine große Heterogenität der Teilnehmenden aus, dementsprechend ist die zentrale Fragestellung der Studie, in der das professionelle Handlungswissen von Lehrenden erforscht wird, die Frage der Binnendifferenzierung. Ausgehend von bereits seit den siebziger Jahren des 20. Jahrhunderts vorliegenden allgemeindidaktischen Entwürfen zur Arbeit mit heterogenen Lerngruppen, in denen das Prinzip der Binnendifferenzierung entwickelt wird, werden im ersten Teil der Arbeit didaktische Möglichkeiten der Binnendifferenzierung im Deutsch als Zweitsprache-Unterricht entworfen. Ausgehend von diesem Vorverständnis ist dann die Befragung der Lehrenden durchgeführt worden, die im zweiten Teil der Arbeit dargestellt, ausgewertet und diskutiert wird. Dabei geht es nicht um eine Evaluation der Praxis anhand vorgefasster Kategorien, sondern im Gegenteil um eine explorative Erforschung des Problembereiches der Arbeit mit heterogenen Lerngruppen im Deutsch als Zweitsprache Unterricht. Anhand der am Material entwickelten Kategorien werden zentrale didaktische Gesichtspunkte herausgearbeitet, die charakteristisch für das Forschungsfeld Deutsch als Zweitsprache mit erwachsenen Einwanderern sind. Diese Kategorien sind nicht deckungsgleich mit denen, die durch die hermeneutisch orientierte Vorgehensweise im ersten Teil der Arbeit entwickelt werden konnten. Anhand dieser Diskrepanz wird das Theorie-Praxis-Verhältnis der didaktischen Forschung und Lehre aufgeschlüsselt und kritisch betrachtet. Ausblick der Arbeit ist der Verweis auf die Professionalisierungsdebatte und die Notwendigkeit einer praxisbezogenen Forschung, welche die Bedürfnisse von Lehrenden direkt einbezieht und im Sinne einer Aktionsforschung gleichzeitig zur Weiterbildung der Lehrenden beiträgt. Nur auf diesem Weg kann die Unterrichtspraxis unmittelbar weiter entwickelt werden. Aus der vorliegenden Studie ergeben sich viel versprechende Anknüpfungspunkte für kooperative Aktionsforschungsprojekte, die von den Lehrenden in den Interviews angeregt werden.

Designing in the real world is complex anyway - so what?

Designing is a heterogeneous, fuzzily defined, floating field of various activities and chunks of ideas and knowledge. Available theories about the foundations of designing as presented in "the basic PARADOX" (Jonas and Meyer-Veden 2004) have evoked the impression of Babylonian confusion. We located the reasons for this "mess" in the "non-fit", which is the problematic relation of theories and subject field. There seems to be a comparable interface problem in theory-building as in designing itself. "Complexity" sounds promising, but turns out to be a problematic and not really helpful concept. I will argue for a more precise application of systemic and evolutionary concepts instead, which - in my view - are able to model the underlying generative structures and processes that produce the visible phenomenon of complexity. It does not make sense to introduce a new fashionable meta-concept and to hope for a panacea before having clarified the more basic and still equally problematic older meta-concepts. This paper will take one step away from "theories of what" towards practice and doing and try to have a closer look at existing process models or "theories of how" to design instead. Doing this from a systemic perspective leads to an evolutionary view of the process, which finally allows to specify more clearly the "knowledge gaps" inherent in the design process. This aspect has to be taken into account as constitutive of any attempt at theory-building in design, which can be characterized as a "practice of not-knowing". I conclude, that comprehensive "unified" theories, or methods, or process models run aground on the identified knowledge gaps, which allow neither reliable models of the present, nor reliable projections into the future. Consolation may be found in performing a shift from the effort of adaptation towards strategies of exaptation, which means the development of stocks of alternatives for coping with unpredictable situations in the future.

Evolving Distributed Algorithms with Genetic Programming

Distributed systems are one of the most vital components of the economy. The most prominent example is probably the internet, a constituent element of our knowledge society. During the recent years, the number of novel network types has steadily increased. Amongst others, sensor networks, distributed systems composed of tiny computational devices with scarce resources, have emerged. The further development and heterogeneous connection of such systems imposes new requirements on the software development process. Mobile and wireless networks, for instance, have to organize themselves autonomously and must be able to react to changes in the environment and to failing nodes alike. Researching new approaches for the design of distributed algorithms may lead to methods with which these requirements can be met efficiently. In this thesis, one such method is developed, tested, and discussed in respect of its practical utility. Our new design approach for distributed algorithms is based on Genetic Programming, a member of the family of evolutionary algorithms. Evolutionary algorithms are metaheuristic optimization methods which copy principles from natural evolution. They use a population of solution candidates which they try to refine step by step in order to attain optimal values for predefined objective functions. The synthesis of an algorithm with our approach starts with an analysis step in which the wanted global behavior of the distributed system is specified. From this specification, objective functions are derived which steer a Genetic Programming process where the solution candidates are distributed programs. The objective functions rate how close these programs approximate the goal behavior in multiple randomized network simulations. The evolutionary process step by step selects the most promising solution candidates and modifies and combines them with mutation and crossover operators. This way, a description of the global behavior of a distributed system is translated automatically to programs which, if executed locally on the nodes of the system, exhibit this behavior. In our work, we test six different ways for representing distributed programs, comprising adaptations and extensions of well-known Genetic Programming methods (SGP, eSGP, and LGP), one bio-inspired approach (Fraglets), and two new program representations called Rule-based Genetic Programming (RBGP, eRBGP) designed by us. We breed programs in these representations for three well-known example problems in distributed systems: election algorithms, the distributed mutual exclusion at a critical section, and the distributed computation of the greatest common divisor of a set of numbers. Synthesizing distributed programs the evolutionary way does not necessarily lead to the envisaged results. In a detailed analysis, we discuss the problematic features which make this form of Genetic Programming particularly hard. The two Rule-based Genetic Programming approaches have been developed especially in order to mitigate these difficulties. In our experiments, at least one of them (eRBGP) turned out to be a very efficient approach and in most cases, was superior to the other representations.

Pharmaceutical consumption and residuals potentially relevant to nutrient cycling in Greater Accra, Ghana

Recycling nutrients form sanitary wastes back into agricultural ecosystems offers an option to alleviate soil depletion in regions where the use of mineral fertiliser is limited. Exemplary nutrient and water cycling approaches, including collection, treatment and use of human urine, are established at Valley View University (VVU) in Greater Accra, Ghana. Concerns have been recently raised in regard to fate and impact of pharmaceutical residues in soils and interlinked environment. To evaluate in how far emerging knowledge can be transposed onto VVU, urban and rural environments in Greater Accra, spatial disease occurrence and drug consumption patterns were studied. Malaria has been found to represent the most severe health burden in Ghana, but there is also a high prevalence of infectious diseases. Drugs consumed in great quantities and in respect to their residual loads potentially problematic in the environment belong to therapeutic groups of: antibiotics, analgesics, drugs for diabetes, antimalarials, cardiovascular drugs and anthelmintics. Drug consumption revealed to be highest in urban and lowest in rural areas. At VVU the range of consumed drugs is comparable to urban areas except for the negligible use of diabetes and cardiovascular medication as well as contraceptives.

The social dimension: a neglected policy item in the Bologna Process

Since its beginning in 1999, the Bologna Process has influenced various aspects of higher education in its member countries, e.g., degree structures, mobility, lifelong learning, social dimension and quality assurance. The social dimension creates the focus of this research. The social dimension entered the Bologna Process agenda in 2001. Despite a decade of reforms, it somehow remained as a vague element and received low scholarly attention. This research addresses to this gap. Firstly, different meanings of the social dimension according to the major European policy actors are analysed. Unfolding the understandings of the actors revealed that the social dimension is mostly understood in terms reflecting the diversity of population on the student body accessing to, progressing in and completing higher education, with a special concern on the underrepresented groups. However, it is not possible to observe a similar commonality concerning the actual policy measures to achieve this goal. Divergence occurs with respect to the addressed underrepresented groups, i.e., all underrepresented groups or people without formal qualifications and mature learners, and the values and institutional interests traditionally promoted by these actors. Secondly, the dissertation discusses the reflection of this social dimension understanding at the national level by looking at cases of Finland, Germany and Turkey. The in-depth analyses show an awareness of the social dimension among most of the national Bologna Process actors and a common understanding of the social dimension goals. However, this understanding has not triggered action in any of the countries. The countries acted on areas which they defined problematic before the Bologna Process. Finally, based on these findings the dissertation discusses the social dimension as a policy item that managed to get into the Bologna Process agenda, but neither grew into an implementable policy, nor drop out of it. To this aim, it makes use of the multiple streams framework and explains the low agenda status social dimension with: i. the lack of a pressing problem definition: the lack of clearly defined indicators and a comprehensive monitoring system, ii. the lack of a viable solution alternative: the proposal of developing national strategies and action plans closed the way to develop generic guidelines for the social dimension to be translated into national policy processes, iii. low political perceptivity: the recent trends opt for increasing efficiency, excellence and exclusiveness discourses rather than ensuring equality and inclusiveness iv. high constraints: the social dimension by definition requires more public funding which is less appreciated and strategic constraints of the actors in allocating their resources v. the type of policy entrepreneur: the social dimension is promoted by an international stakeholder, the European Students’ Union, instead of the ministers responsible for higher education The social dimension remains a policy item in the Bologna Process which is noble enough to agree but not urgent enough to act on.

The Transatlantic Trade and Investment Partnership (TTIP)

The United States of America and the European Union are currently negotiating a Transatlantic Trade and Investment Partnership (TTIP). It is one of the most ambitious free trade and investment initiatives, going much further than eliminating tariffs. TTIP mainly aims at reducing “non-tariff barriers”. While tariffs on goods have been imposed with an eye to foreign competition, most of the non-tariff barriers are the laws and regulations that are the result of social struggles for the protection of consumers and workers. It is therefore certain that TTIP will impact workers. This volume provides a preliminary assessment of the likely consequences for labor by: - providing an overall introduction to the TTIP negotiations; -assessing the reliability of the studies claiming employment gains; - highlighting specific problematic proposals such as the investor-to-state dispute settlement mechanism; - presenting the position of organized labor from both sides of the Atlantic. / Among the contributors are Stefan Beck (Kassel), Lance Compa (Ithaca, New York), Pia Eberhardt (Brussels) and Werner Raza (Vienna).

The Koundoum sheep breed in Niger: morpho-biometric study and description of the production system

The diffusion of highly productive breeds across developing countries goes along with a neglect of indigenous breeds, which are well suited to their environment but often show low yields. Thus, in Niger, the flock of Koundoum sheep are rapidly decreasing. The Koundoum is one of the few wool sheep breeds of Africa and shows important adaptive feature to its native environment, i.e. the humid pastures on the banks of the Niger River. To characterise the breed and to understand its production context, a survey has been conducted in 104 herds in four communes along the Niger River (Kollo, Tillabery, Say and Tera). Nine body measurements, including live weight, were taken on 180 adult sheep (101 females and 79 males). The herds varied from 2 to 60 heads, with a median size of eight animals and two thirds of the herds having less than 10 animals. Mainly fed on natural pastures, 85.6% of the herds received crop residues. Only natural mating was practiced. Veterinary care was restricted to anti-helminthic and some indigenous treatments. The frequent affiliation of breeders to professional unions appeared as favourable to the implementation of a collective conservation program. The Koundoum sheep were white or black coated, with the black colour being most frequent (75.6%). Wattles were present in both sexes at similar frequencies of around 14%. All biometric variables were significantly and positively correlated between them. The thoracic perimeter showed the best correlation with live weight in both males and females. Three variables were selected for live weight prediction: thoracic perimeter, height at withers and rump length. From the present study, it is expected that the in situ conservation of the Koundoum sheep will be highly problematic, due to lack of market opportunities for wool and the willingness of smallholders to get involved in pure Koundoum rearing.

Incremental Verification of Timing Constraints for Real-Time Systems

Testing constraints for real-time systems are usually verified through the satisfiability of propositional formulae. In this paper, we propose an alternative where the verification of timing constraints can be done by counting the number of truth assignments instead of boolean satisfiability. This number can also tell us how “far away” is a given specification from satisfying its safety assertion. Furthermore, specifications and safety assertions are often modified in an incremental fashion, where problematic bugs are fixed one at a time. To support this development, we propose an incremental algorithm for counting satisfiability. Our proposed incremental algorithm is optimal as no unnecessary nodes are created during each counting. This works for the class of path RTL. To illustrate this application, we show how incremental satisfiability counting can be applied to a well-known rail-road crossing example, particularly when its specification is still being refined.

News from compositions, the R package

The R-package “compositions”is a tool for advanced compositional analysis. Its basic functionality has seen some conceptual improvement, containing now some facilities to work with and represent ilr bases built from balances, and an elaborated subsys- tem for dealing with several kinds of irregular data: (rounded or structural) zeroes, incomplete observations and outliers. The general approach to these irregularities is based on subcompositions: for an irregular datum, one can distinguish a “regular” sub- composition (where all parts are actually observed and the datum behaves typically) and a “problematic” subcomposition (with those unobserved, zero or rounded parts, or else where the datum shows an erratic or atypical behaviour). Systematic classification schemes are proposed for both outliers and missing values (including zeros) focusing on the nature of irregularities in the datum subcomposition(s). To compute statistics with values missing at random and structural zeros, a projection approach is implemented: a given datum contributes to the estimation of the desired parameters only on the subcompositon where it was observed. For data sets with values below the detection limit, two different approaches are provided: the well-known imputation technique, and also the projection approach. To compute statistics in the presence of outliers, robust statistics are adapted to the characteristics of compositional data, based on the minimum covariance determinant approach. The outlier classification is based on four different models of outlier occur- rence and Monte-Carlo-based tests for their characterization. Furthermore the package provides special plots helping to understand the nature of outliers in the dataset. Keywords: coda-dendrogram, lost values, MAR, missing data, MCD estimator, robustness, rounded zeros

GRASS GIS for the distinction of vegetation from buildings using LiDAR altimetric data

La tecnología LiDAR (Light Detection and Ranging), basada en el escaneado del territorio por un telémetro láser aerotransportado, permite la construcción de Modelos Digitales de Superficie (DSM) mediante una simple interpolación, así como de Modelos Digitales del Terreno (DTM) mediante la identificación y eliminación de los objetos existentes en el terreno (edificios, puentes o árboles). El Laboratorio de Geomática del Politécnico de Milán – Campus de Como- desarrolló un algoritmo de filtrado de datos LiDAR basado en la interpolación con splines bilineares y bicúbicas con una regularización de Tychonov en una aproximación de mínimos cuadrados. Sin embargo, en muchos casos son todavía necesarios modelos más refinados y complejos en los cuales se hace obligatorio la diferenciación entre edificios y vegetación. Este puede ser el caso de algunos modelos de prevención de riesgos hidrológicos, donde la vegetación no es necesaria; o la modelización tridimensional de centros urbanos, donde la vegetación es factor problemático. (...)

La Nueva Era : mercado y crisis de sentido. Estudio exploratorio realizado en Bogotá

Es una investigación pionera que pretende comprender el desarrollo del fenómeno social Nueva Era en Bogotá, por ello el objetivo de este estudio es indagar sobre los motivos que tiene los bogotanos para consumir productos y servicios de la Nueva Era. A partir de una metodología de investigación cualitativa donde se utilizaron técnicas de recolección tales como: la entrevista semi-estructurada, el cuestionario y la observación participante donde las unidades de análisis fueron los propietarios y consumidores de tres centros calificados Nueva Era que fueron, Serviteca del Alma, Centro Unifinismo, Wahikarie de Colombia E.U, se logro corroborar la hipótesis que el capitalismo informacional con su economía de mercado y la globalización que han generado una sociedad de red, ha desatado una crisis de sentido en los individuos, el llamado mercado “Nueva Era” es una alternativa para resolver dicha problemática.

Factores que detienen la generación de unidades de la meta en empresas que prestan servicios de rehabilitación a personas en condición de discapacidad

El objetivo del presente trabajo es el de presentar los diferentes factores administrativos que determinan la velocidad de generación de unidades de la meta de empresas que prestan servicios de rehabilitación a personas en condición de discapacidad física y/o cognitiva del Distrito Capital. Para cumplir este objetivo nos centramos en el estudio de una Institución tipo que presta servicios de rehabilitación, especialmente a niños con discapacidad. El alcance del trabajo, es la caracterización de una empresa que brinda servicios de rehabilitación, revisar que factores administrativos pueden resaltarse como importantes y necesarios dentro de la organización, establecer cuales son los efectos indeseables que tiene una institución de este tipo y por ultimo estimar cual puede ser el factor restrictivo que detiene la velocidad de generación de las unidades de meta de este tipo de empresas. Los autores aplicaron la Teoría de Restricciones TOC en este trabajo, por considerar que desde su filosofía, esta teoría proporciona los lineamientos para aproximarse a la problemática y para sugerir soluciones, que están plasmadas en un plan de acción de inmediata implementación y con rápidos y eficaces resultados. Esperamos que con este estudio se contribuya en la reflexión y en la redefinición de las empresas que prestan servicios de rehabilitación, para lograr, con las herramientas que la Teoría de Restricciones brinda, el desarrollo de un pensamiento interno que favorezca la mejora continua la cual redundara en mejores servicios para sus usuarios.

Amenaza a los derechos de autor

En este reportaje realizo una investigación acerca de la problemática de la piratería en los derechos de autor (cine, música, software e industria editorial) para posteriormente indagar acerca del tema en el contexto actual colombiano.

El poder del derecho urbanístico en la asignación de contenidos a los cuatro elementos estructurales de la propiedad privada

La tesis identifica y analiza los puntos de confrontación entre el derecho urbanístico y el derecho de propiedad, desarrollando reglas de ponderación para el tratamiento de la problemática.