SLAM using an Imaging Sonar for Partially Structured Underwater Environments

In this paper we describe a system for underwater navigation with AUVs in partially structured environments, such as dams, ports or marine platforms. An imaging sonar is used to obtain information about the location of planar structures present in such environments. This information is incorporated into a feature-based SLAM algorithm in a two step process: (I) the full 360deg sonar scan is undistorted (to compensate for vehicle motion), thresholded and segmented to determine which measurements correspond to planar environment features and which should be ignored; and (2) SLAM proceeds once the data association is obtained: both the vehicle motion and the measurements whose correct association has been previously determined are incorporated in the SLAM algorithm. This two step delayed SLAM process allows to robustly determine the feature and vehicle locations in the presence of large amounts of spurious or unrelated measurements that might correspond to boats, rocks, etc. Preliminary experiments show the viability of the proposed approach

Underwater SLAM in a marina environment

This paper describes a navigation system for autonomous underwater vehicles (AUVs) in partially structured environments, such as dams, harbors, marinas or marine platforms. A mechanical scanning imaging sonar is used to obtain information about the location of planar structures present in such environments. A modified version of the Hough transform has been developed to extract line features, together with their uncertainty, from the continuous sonar dataflow. The information obtained is incorporated into a feature-based SLAM algorithm running an Extended Kalman Filter (EKF). Simultaneously, the AUV's position estimate is provided to the feature extraction algorithm to correct the distortions that the vehicle motion produces in the acoustic images. Experiments carried out in a marina located in the Costa Brava (Spain) with the Ictineu AUV show the viability of the proposed approach

The effect of colostrum source (goat vs. sheep) and timing of the first colostrum feeding (2h vs. 14h after birth) on body weight and immune status of artificially reared newborn lambs.

Several factors can affect lamb body weight (BW) and immune status during the first days of life, including colostrum source and timing of the first colostrum feeding. The aim of this study was to evaluate the effects of colostrum source (goat or sheep) and timing of the first colostrum feeding (2 or 14h after birth) on lamb BW and immune status. In this study, 40 lambs were removed from their dams at birth and randomly assigned into 4 groups of 10 lambs each. Lambs were subsequently fed at 2 or 14h after birth with goat or sheep colostrum. Blood samples and BW recording were performed before feeding. Blood plasma was used to measure the immunoglobulin concentration (IgG and IgM), chitotriosidase activity, and complement system activity (total and alternative pathways). In general, no differences in any of the measured variables were observed among the 4 groups, indicating that neither colostrum source nor timing of the first colostrum feeding had an effect on these variables. These findings may improve management on lamb farms that raise animals under artificial conditions, because our results indicate that it is not necessary to feed colostrum to lambs immediately after birth and that goat colostrum may be used to feed newborn lambs.

Hidrossedimentologia e disponibilidade h��drica da bacia hidrogr��fica da Barragem de Poil��o

TEIXEIRA, Jos�� Jo��o Lopes. Departamento de Engenharia Agr��cola, Centro de Ci��ncias Agr��rias da Universidade Federal do Cear��, Agosto de 2011. Hidrossedimentologia e disponibilidade h��drica da bacia hidrogr��fica da Barragem de Poil��o, Cabo Verde. Orientador: Jos�� Carlos de Ara��jo. Examinadores: George Leite Mamede, Pedro Henrique Augusto Medeiros. O Arquip��lago de Cabo Verde, situado na costa ocidental africana, sofre influ��ncia do deserto de Saara tornando o clima caraterizado por pluviometria muito baixa e distribu��da irregularmente no espa��o e no tempo. As chuvas s��o muito concentradas, gerando grandes escoamentos para o mar. O aumento da disponibilidade h��drica requer al��m da constru����o e manuten����o de infraestrutura de capta����o e conserva����o de ��guas pluviais, uma gest��o eficiente destes recursos. Atualmente, constitui um dos eixos estrat��gicos da pol��tica do estado de Cabo Verde, a capta����o, armazenamento e mobiliza����o de ��guas superficiais atrav��s de constru����o de barragens. Estudos do comportamento hidrol��gico e sedimentol��gico do reservat��rio e da sua bacia de contribui����o constituem premissas b��sicas para um ��timo dimensionamento, gest��o e monitoramento da referida infraestrutura. �� neste sentido que o presente estudo objetivou sistematizar informa����es hidrol��gicas e sedimentol��gicas da bacia hidrogr��fica da Barragem de Poil��o (BP) e apresentar proposta operacional de longo prazo. A ��rea de estudo ocupa 28 km�� a montante da Bacia Hidrogr��fica da Ribeira Seca (BHRS) na Ilha de Santiago. A altitude da bacia varia de 99 m, situada na cota da barragem, at�� 1394 m. Para o estudo, foram utilizados e sistematizados, s��rie pluviom��trica de 1973 a 2010, registos de vaz��o instant��nea do per��odo 1984 a 2000 e registos agroclim��ticos da ��rea de estudo (1981 a 2004). Para o preenchimento das falhas tanto dos escoamentos como da descarga s��lida em suspens��o, foi utilizado o m��todo de curva chave. Para estimativa de produ����o de sedimentos na bacia, aplicou-se a Equa����o Universal de Perda de Solo (USLE) e a raz��o de aporte de sedimentos (SDR). O ��ndice de reten����o de sedimentos no reservat��rio foi estimado pelo m��todo de Brune e a distribui����o de sedimento pelo m��todo emp��rico de redu����o de ��rea descrito por Borland e Miller e, revisado por Lara. Para gerar e simular curvas de vaz��o versus garantia foi utilizado c��digo computacional VYELAS, desenvolvido por Ara��jo e baseado na abordagem de Campos. Tamb��m foi avaliada a redu����o da vaz��o de retirada do per��odo 2006 a 2026, provocado pelo assoreamento do reservat��rio. Concluiu-se que em m��dia a precipita����o anual �� de 323 mm, concentrando-se 73% nos meses de agosto e setembro; a bacia de contribui����o apresenta como valor um n��mero de curva (CN) de 76, com abstra����o inicial (Ia) de 26 mm, coeficiente de escoamento de 19% e uma vaz��o anual afluente de 1,7 hm��(cv= 0,73); a disponibilidade h��drica para uma garantia de 85% �� avaliada em 0,548 hm��/ano e n��o 0,671 hm��/ano como indica o projeto original. Com uma descarga s��lida estimada em 22.185 m��/ano conclui-se que at�� o ano de 2026, a capacidade do reservat��rio reduz a uma taxa de 1,8 % ao ano, devido ao assoreamento, provocando uma redu����o de 41% da disponibilidade h��drica inicial. Nessa altura, as perdas por evapora����o e sangria ser��o da ordem de 81% da vaz��o afluente de entrada no reservat��rio. Na base desses resultados se apresentou proposta de opera����o da BP.

Soil and water conservation strategies and impact on sustainable livelihood in Cape Verde ��� Case study of Ribeira Seca watershed

Cape Verde, located off the coast of Senegal in western Africa, is a volcanic archipelago where a combination of human, climatic, geomorphologic and pedologic factors has led to extensive degradation of the soils. Like other Sahelian countries, Cape Verde has suffered the effects of desertification through the years, threatening the livelihood of the islands population and its fragile environment. In fact, the steep slopes in the ore agricultural islands, together with semi-arid and arid environments, characterized by an irregular and poorly distributed rainy season, with high intensity rainfall events, make dryland production a challenge. To survive in these fragile conditions, the stabilization of the farming systems and the maintenance of sustainable yields have become absolute priorities, making the islands an erosion control laboratory. Soil and water conservation strategies have been a centerpiece of the government0s agricultural policies for the last half century. Aiming to maintain the soil in place and the water inside the soil, the successive governments of Cape Verde have implemented a number of soil and water conservation techniques, the most common ones being terraces, half moons, live barriers, contour rock walls, contour furrows and microcatchments, check dams and reforestation with drought resistant species. The soil and water conservation techniques implemented have contributed to the improvement of the economical and environmental conditions of the treated landscape, making crop production possible, consequently, improving the livelihood of the people living on the islands. In this paper, we survey the existing soil and water conservation techniques, analyze their impact on the livelihood condition of the population through a thorough literature review and field monitoring using a semi-quantitative methodology and evaluate their effectiveness and impact on crop yield in the Ribeira Seca watershed. A brief discussion is given on the cost and effectiveness of the techniques to reduce soil erosion and to promote rainfall infiltration. Finally, we discuss the critical governance factors that lead to the successful implementation of such strategy in a country with scarce natural resources.

Analysis of past and future dam formation and failure in the Santa Cruz River (San Juan province, Argentina)

Around 11.5 * 106 m3 of rock detached from the eastern slope of the Santa Cruz valley (San Juan province, Argentina) in the first fortnight of January 2005. The rockslide?debris avalanche blocked the course, resulting in the development of a lake with maximum length of around 3.5 km. The increase in the inflow rate from 47,000?74,000 m3/d between April and October to 304,000 m3/d between late October and the first fortnight of November, accelerated the growing rate of the lake. On 12 November 2005 the dam failed, releasing 24.6 * 106 m3 of water. The resulting outburst flood caused damages mainly on infrastructure, and affected the facilities of a hydropower dam which was under construction 250 km downstream from the source area. In this work we describe causes and consequences of the natural dam formation and failure, and we dynamically model the 2005 rockslide?debris avalanche with DAN3D. Additionally, as a volume ~ 24 * 106 m3of rocks still remain unstable in the slope, we use the results of the back analysis to forecast the formation of a future natural dam. We analyzed two potential scenarios: a partial slope failure of 6.5 * 106 m3 and a worst case where all the unstable volume remaining in the slope fails. The spreading of those potential events shows that a new blockage of the Santa Cruz River is likely to occur. According to their modeled morphometry and the contributing watershed upstream the blockage area, as the one of 2005, the dams would also be unstable. This study shows the importance of back and forward analysis that can be carried out to obtain critical information for land use planning, hazards mitigation, and emergency management.

As Barragens em cabo Verde - Avalia����o dos Impactes Ambientais - Socioecon��micos e Culturais - Caso de Estudo - A Barragem do Poil��o Ilha Santiago

Os sucessivos anos de seca t��m agravado a cr��nica falta de ��gua que marca o quadro h��drico de Cabo Verde. No arquip��lago verifica-se a perda de um grande volume de ��gua que se escoa para o mar, aquando das grandes chuvadas, e que �� estimado em milh��es de m3/ano. Para atenuar a problem��tica da falta de ��gua, principalmente no setor agr��cola, o Governo Cabo-verdiano tem apostado na pol��tica de constru����o de barragens. No ano de 2006 com o objetivo de aumentar os recursos h��dricos dispon��veis e concomitantemente alargar a ��rea irrigada e diminuir a pobreza, foi inaugurada a barragem do Poil��o, a primeira do arquip��lago, no interior da ilha de Santiago no concelho de S��o Louren��o dos ��rg��os. Baseado no pressuposto que as barragens s��o estruturas de grande impacte ambiental e socioecon��mico, antes, durante e depois da sua constru����o, o presente trabalho tem como objetivo principal avaliar o desempenho ambiental, socioecon��mico e cultural da Barragem de Poil��o. Para tal, o trabalho segue uma metodologia DPSIR1e a aplica����o de inqu��ritos e entrevistas, procurando integrar o conhecimento e a perce����o da paisagem na ��rea de influ��ncia da albufeira por parte de diversos atores locais. Espera-se colher subs��dios que sirvam de base para os estudos futuros das demais barragens projetadas e a serem constru��das em Cabo Verde.

Caracter��sticas geol��gicas y geot��cnicas de los lodos de flotaci��n de la Sierra Minera de Cartagena-La Uni��n (SE Espa��a)

We present the results of a geological and geotechnical characterization of the metallurgic waste from the Sierra Minera de Cartagena-La Union. We have studied eight tailings dams from which we collected and analysed 42 samples of metallurgic waste. We measured grainsize distribution, the specific gravity of solid particles, plasticity index, permeability, both in situ and in the laboratory, direct shear characteristicsand moisture content. According to size distribution the tailings can be classified as sandy silt. Their plasticity index ranges from medium to nil. The internal friction angle varies between 28 and 42 degrees. Cohesion is between 0 and 2.2 t/m2. The specific gravity of the solid particles ranges widely from 1.8 to 4 g/cm3. The saturated hydraulic conductivity values vary between 1.3x 10-5 and 3.2x 10-9 m/s.The water content measured in situ shows that the degree of saturation remains relatively high despite low rainfall and high evaporation rates. Several tailings dams have failed. The leading causes of tailings-dam failure are: 1) slope instability; 2) overflow; 3) erosion; and 4) subsidence or collapse. The main factor leading to dam failure is that the tailings stored in the ponds are highly saturated

Effects of erosion and deposition on particle size distribution of deposited farmland soils on the chinese loess plateau

Particle size distribution (PSD) in the soil profile is strongly related to erosion, deposition, and physical and chemical processes. Water cycling and plant growth are also affected by PSD. Material sedimented upstream of the dam constructions formed large areas of deposited farmland (DF) soils on the Chinese Loess Plateau (CLP), which has been the site of the most severe soil erosion in the world. Two DFs without tillage on the CLP were chosen to study the combined effect of erosion and check dams on PSD. Eighty-eight layers (each 10 cm thick) of filled deposited farmland (FDF) soils and 22 layers of silting deposited farmland (SDF) soils of each studied soil profile were collected and 932 soil samples were investigated using laser granulometry. The particle sizes were stratified in both DFs based on soil properties and erosion resistance. The obtained results of clay and silt fractions showed similar horizontal distribution, indicating parallel characteristics of erosion and deposition processes. Fine sand represented the largest fraction, suggesting the preferential detachment of this fraction. The most erodible range of particle sizes was 0.25-0.5 mm, followed by 0.2-0.25 mm in the studied soil profiles. The correlation between particle size and soil water contents tended to increase with increasing water contents in FDF. Due to the abundant shallow groundwater, the relationship between particle size and soil water content in SDF was lost. Further studies on PSD in the DF area are needed to enhance the conservation management of soil and water resources in this region.

Home Tightening, Insulation and Ventilation, 2011

The average Iowa family spends more than half of its annual household energy bill on heating and cooling. That���s a significant number, but you can dramatically reduce these costs���up to 20 percent, according to ENERGY STAR�����by making some simple energy-saving weatherization and insulation improvements to your home. In addition���with a little attention to proper ventilation���you can protect your home from moisture damage year-round, reduce problems caused by ice dams on the roof during the winter and significantly cut summer cooling costs. As a bonus, these projects can extend the life of your home and may increase the resale value of your property. If you like to fix things around the house, you can handle many of the projects suggested in this book and make the most of your energy-improvement budget. However, don���t hesitate to call a professional for help if you���d rather not do the work yourself; the dollars gained through energy savings in upcoming years will be worth the expense.

Infraestructuras y desarrollo econ��mico en el Pirineo Central (1850-2000)

This paper is aimed at describing the impact of infrastructure on the economic evolution of Central Pyrenees (i.e., Huesca and the Catalan"Alt Pirineu"). The text analyses if investment in railways, roads and dams favoured economic development or, on the contrary, was just an instrument to extract domestic resources. The paper distinguishes among three different periods. Firstly, during the second half of the nineteenth century and the first few years of the twentieth century, the lack of railway connections prevented the economic development of the area. Secondly, between the first decades of the twentieth century and 1975, a road network was set up that reinforced the economic decadence of the most depressed valleys, and the construction of large dams was a powerful factor of depopulation all over the region. Finally, from 1975 onwards, some trends may be observed towards the correction of the previous policies.

Effects of lactation upon circulating plasma metabolites in cafeteria-fed rats

1. The effects of "cafeteria feeding" on primiparous Wistar rats during lactation have been studied by measuring circulating levels of glucose, amino acids, lactate, urea and ammonia as well as glycogen levels in liver and muscle. 2. No significant changes in glucose levels were observed despite alterations in blood glucose compartmentation. 3. Compared with controls, the dams given the cafeteria diet had higher liver glycogen stores which were more easily mobilized at the peak of lactation. 4. Rats given the cafeteria diet showed a lower amino acid utilization than controls and adequately maintained circulating levels, as determined by the lower circulating levels of ammonia and urea. 5. No significant differences in body-weight were observed in the period studied despite increasing dam weight after weaning in the cafeteria-fed group. 6. The size of pups of cafeteria-fed dams was greater than that of controls, and the differences were marked after weaning, when the metabolic machinery of the cafeteria pup maintained high protein accretion and body build-up using fat as the main energy substrate characteristic of the preweaning stage. The controls, however, changed to greater utilization of amino acids as an energy substrate and adapted to high-protein (lowbiological-quality) diets with a significantly different pattern of circulating nitrogen distribution.

Iowa 2014 Transportation Map, 2014

Transportation map of Iowa, updated march 1, 2014. map focuses on interstate highways, primary and secondary state roads, county roads, and scenic byways. Also includes railroad lines, airports, waterways, and locks and dams. All 99 counties are represented, as well as approximately 1,000 cities and towns. Points of interest are also marked.

Immunomodulation by conjugated linoleic acid (CLA) in early life

Conjugated linoleic acid (CLA) has been reported to exert beneficial physiological effects on body composition and the immune system. However, little information is available on the influence of CLA on immune function during early life periods. The present study evaluates the effect of feeding an 80:20 mixture of cis-9,trans-11- and trans-10,cis-12-CLA isomers duringgestation, suckling and early infancy on the systemic and mucosal immune responses of Wistar rats at three different time points: at the end of the suckling period (21-day-old rats), in early infancy (28-day-old rats), and later in life (adulthood). Cis-9,trans-11- and trans-10,cis-12-CLA isomers were detected in the milk of CLA-fed dams and in the plasma of all CLA-supplemented pups, and the highest content was achieved in those rats supplemented over the longest period. Dietary supplementation with that CLA mix enhances the systemic production of the main in vivo and ex vivo immunoglobulin (Ig) isotypes in 21- and 28-day-old rats. Moreover, CLA supplementation during suckling and early infancy also enhances the humoral immune defenses at intestinal level, by means of mucosal IgA increase, whereas down-regulates thesystemic lymphoproliferative response. Finally, we described herein how feeding a diet enriched with the same isomer mix of cis9,trans11- and trans10,cis12-CLA from gestation to adulthood improves the capacity of adult rats to achieve a specific systemic and mucosal immune responses. All these data support the immunomodulatory effects of dietary supplementation of CLA, particularly of the cis9,trans11-CLA isomer, during early stages of life on immune system development, as well as the long-term effects on the specific immune response in adult age.

Efecte del tipus d'embassament en el r��gim de cabals m��nims a la conca del riu Ebre

En el marc dels cabals ambientals o ���ecol��gics���, el coneixement de la regulaci�� del r��gim de cabals m��nims o baixos per part de les infraestructures hidr��uliques pren especial import��ncia. En aquest treball, es contrasta la hip��tesi de que la regulaci�� del r��gim fluvial per part dels embassaments de regadiu i per part dels embassaments destinats a la producci�� d���energia hidroel��ctrica produeix una alteraci�� diferent en el r��gim de cabals m��nims. Per fer-ho, es realitza l���an��lisi comparatiu del grau d���assoliment hist��ric dels cabals m��nims ecol��gics, determinats en el nou Pla de Conca de l���Ebre 2010-15, en 30 trams fluvials representatius de l���efecte d���aquests tipus d���embassaments. Els resultats obtinguts indiquen que la tipologia d�����s dels embassaments ��s determinant en la regulaci�� dels cabals m��nims. Els embassaments de reg produeixen una major alteraci�� del r��gim de cabals m��nims i presenten una diferent distribuci�� i una major variabilitat intraanual en aquesta alteraci�� que els embassaments hidroel��ctrics.