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Sample records for dar es salaam

  1. Green vegetable supply in Dar es Salaam

    NARCIS (Netherlands)

    Wegerif, M.C.A.

    2015-01-01

    This article constructs a picture of green vegetable growing and supply in Dar es Salaam by looking at the lives and work of a small trader and an urban farmer. It reveals the importance of a range of distribution and trade networks and the integration of a wider city region, alongside urban and per

  2. Accessibility, Congestion and Travel Delays in Dar es Salaam

    DEFF Research Database (Denmark)

    Melbye, Dea Christine; Møller-Jensen, Lasse; Andreasen, Manja Hoppe

    2015-01-01

    on to present a review of research into travel speed levels and congestion in Dar es Salaam. A set of city-wide maps of accessibility and delay levels are constructed based on available speed data and road network data obtained from the OpenStreetMap project and the findings are discussed with respect...

  3. Disposal frequencies of selected recyclable wastes in Dar es Salaam.

    Science.gov (United States)

    Mgaya, Prosper; Nondek, Lubomir

    2004-01-01

    A statistical survey of households based upon questionnaires distributed via primary schools has been carried out in five wards of Dar es Salaam, Tanzania, to estimate disposal frequencies (number of items disposed per week) for newsprint, metal cans, glass and plastic containers and plastic shopping bags. Plastic shopping bags are disposed most frequently while glass containers are disposed least frequently. The statistical distribution of disposal frequencies, which seems to be influenced by household income, is well described by Poisson distribution. Disposal frequencies are mutually correlated at 95% level of probability despite the differences in disposal patterns of individual households.

  4. Green infrastructure for flood risk management in Dar es Salaam and Copenhagen

    DEFF Research Database (Denmark)

    Mguni, Patience; Herslund, Lise Byskov; Jensen, Marina Bergen

    2015-01-01

    , a comparison of the opportunities and barriers to the implementation of SUDS in Dar es Salaam and Copenhagen is presented. The results indicate that a bottom-up approach in Dar es Salaam is important, with the community level taking the lead, while in Copenhagen the top-down approach currently employed...

  5. Urban agriculture and Anopheles habitats in Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Stefan Dongus

    2009-05-01

    Full Text Available A cross-sectional survey of agricultural areas, combined with routinely monitored mosquito larval information, was conducted in urban Dar es Salaam, Tanzania, to investigate how agricultural and geographical features may influence the presence of Anopheles larvae. Data were integrated into a geographical information systems framework, and predictors of the presence of Anopheles larvae in farming areas were assessed using multivariate logistic regression with independent random effects. It was found that more than 5% of the study area (total size 16.8 km2 was used for farming in backyard gardens and larger open spaces. The proportion of habitats containing Anopheles larvae was 1.7 times higher in agricultural areas compared to other areas (95% confidence interval = 1.56-1.92. Significant geographic predictors of the presence of Anopheles larvae in gardens included location in lowland areas, proximity to river, and relatively impermeable soils. Agriculture-related predictors comprised specific seedbed types, mid-sized gardens, irrigation by wells, as well as cultivation of sugar cane or leafy vegetables. Negative predictors included small garden size, irrigation by tap water, rainfed production and cultivation of leguminous crops or fruit trees. Although there was an increased chance of finding Anopheles larvae in agricultural sites, it was found that breeding sites originated by urban agriculture account for less than a fifth of all breeding sites of malaria vectors in Dar es Salaam. It is suggested that strategies comprising an integrated malaria control effort in malaria-endemic African cities include participatory involvement of farmers by planting shade trees near larval habitats.

  6. Urban agriculture and Anopheles habitats in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Dongus, Stefan; Nyika, Dickson; Kannady, Khadija; Mtasiwa, Deo; Mshinda, Hassan; Gosoniu, Laura; Drescher, Axel W; Fillinger, Ulrike; Tanner, Marcel; Killeen, Gerry F; Castro, Marcia C

    2009-05-01

    A cross-sectional survey of agricultural areas, combined with routinely monitored mosquito larval information, was conducted in urban Dar es Salaam, Tanzania, to investigate how agricultural and geographical features may influence the presence of Anopheles larvae. Data were integrated into a geographical information systems framework, and predictors of the presence of Anopheles larvae in farming areas were assessed using multivariate logistic regression with independent random effects. It was found that more than 5% of the study area (total size 16.8 km2) was used for farming in backyard gardens and larger open spaces. The proportion of habitats containing Anopheles larvae was 1.7 times higher in agricultural areas compared to other areas (95% confidence interval = 1.56-1.92). Significant geographic predictors of the presence of Anopheles larvae in gardens included location in lowland areas, proximity to river, and relatively impermeable soils. Agriculture-related predictors comprised specific seedbed types, mid-sized gardens, irrigation by wells, as well as cultivation of sugar cane or leafy vegetables. Negative predictors included small garden size, irrigation by tap water, rainfed production and cultivation of leguminous crops or fruit trees. Although there was an increased chance of finding Anopheles larvae in agricultural sites, it was found that breeding sites originated by urban agriculture account for less than a fifth of all breeding sites of malaria vectors in Dar es Salaam. It is suggested that strategies comprising an integrated malaria control effort in malaria-endemic African cities include participatory involvement of farmers by planting shade trees near larval habitats.

  7. Determinants of acceptance of cervical cancer screening in Dar es Salaam, Tanzania

    DEFF Research Database (Denmark)

    Kahesa, Crispin; Kjaer, Susanne; Mwaiselage, Julius;

    2012-01-01

    ABSTRACT: OBJECTIVE: To describe how demographic characteristics and knowledge of cervical cancer influence screening acceptance among women living in Dar es Salaam, Tanzania. METHODS: Multistage cluster sampling was carried out in 45 randomly selected streets in Dar es Salaam. Women between...... cervical cancer screening can be increased in Dar es Salaam. Special attention should be paid to women of low education and women of high parity. In addition, knowledge and awareness raising campaigns that goes hand in hand with culturally acceptable screening services will likely lead to an increased...

  8. Epidemiological Studies on Bovine Mastitis in Smallholder Dairy Herds in the Dar es Salaam Region, Tanzania

    NARCIS (Netherlands)

    Kivaria, F.M.

    2006-01-01

    Recently the number of milking cows has increased substantially in the Dar es Salaam region due to an increasing demand for fresh milk in this densely populated urban centre. It is estimated that there are 1,765 smallholder dairy herds with 8,233 improved dairy animals in and around the Dar es Sala

  9. Elemental Contents in Hair of Children from Two Regions in Dar Es Salaam

    Directory of Open Access Journals (Sweden)

    Najat K. Mohammed

    2012-01-01

    Full Text Available The work presented in this paper is part of the study which aims at determining the levels of elements in hair of children in Tanzania as a bioindicator of their nutrition and health. In this paper, the levels of trace elements in hair from children living in Dar es Salaam have been analysed. The analysis was carried out by long and short irradiation INAA at the reactor centre of the Institute of Nuclear Physics, Rez Czech Republic. 22 samples were collected from children living at Kiwalani about 12 km from Dar es Salaam city and 16 samples from children living at Mlimani, the main campus of University of Dar es Salaam. A total of 34 elements were found in the hair of the children. There were no big differences between the concentration levels of the essential elements in hair samples collected from the children which might indicate the same food consumption habits.

  10. Contraceptive Method Choice Among Women Attending at Amtullabhai Family Planning Clinic in Dar es salaam

    OpenAIRE

    Mbando, Apaisaria Humphrey

    2011-01-01

    Contraceptive prevalence in Tanzania is low despite high knowledge of contraception. In order to understand the existing barriers, it is important to find out reasons affecting contraceptive method choices. The objective of this study was to assess contraceptive method choice among women attending at Amtullabhai family planning clinic in Dar es Salaam. A cross- sectional study was conducted between October and November, 2010 at Amtullabhai family planning clinic, Ilala District in Dar es Sala...

  11. Students' Experiences and Challenges of Blended Learning at the University of Dar Es Salaam, Tanzania

    Science.gov (United States)

    Mtebe, Joel S.; Raphael, Christina

    2013-01-01

    Recent developments in Information and Communication Technologies (ICTs), especially eLearning, have heightened the need for University of Dar es Salaam (UDSM) to supplement on-campus face-to-face delivery as well as meeting increased students' enrolments through blended distance learning. Since 2008, the University has been offering three…

  12. Making the African city : Dakar, Dar es Salaam, Kinshasa, 1920-1980

    NARCIS (Netherlands)

    Beeckmans, Luce Manu R.

    2013-01-01

    In her PhD thesis Making the African City, Luce Beeckmans analyses the African city from a comparative perspective. By means of three case studies, the historical development between 1920 and 1980 of three cities in sub-Saharan Africa, Dakar (Senegal), Dar es Salaam (Tanzania) and Kinshasa (Congo),

  13. Making the African city : Dakar, Dar es Salaam, Kinshasa, 1920-1980

    NARCIS (Netherlands)

    Beeckmans, Luce Manu R.

    2012-01-01

    In her PhD thesis Making the African City, Luce Beeckmans analyses the African city from a comparative perspective. By means of three case studies, the historical development between 1920 and 1980 of three cities in sub-Saharan Africa, Dakar (Senegal), Dar es Salaam (Tanzania) and Kinshasa (Congo),

  14. How Children Living in Poor Areas of Dar Es Salaam, Tanzania Perceive Their Own Multiple Intelligences

    Science.gov (United States)

    Dixon, Pauline; Humble, Steve; Chan, David W.

    2016-01-01

    This study was carried out with 1,857 poor children from 17 schools, living in low-income areas of Dar Es Salaam, Tanzania. All children took the "Student Multiple Intelligences Profile" (SMIP) questionnaire as part of a bigger project that gathered data around concepts and beliefs of talent. This paper sets out two aims, first to…

  15. Child Labour in Urban Agriculture: The Case of Dar es Salaam, Tanzania.

    Science.gov (United States)

    Mlozi, Malongo R. S.

    1995-01-01

    Urban agriculture in Dar es Salaam was found to use child labor of both children with parents of higher and lower socioeconomic status (SES). Discusses policy implications and calls for the education of parents of lower SES not to expect an economic contribution from their children's labor, and the education of children about their rights. (LZ)

  16. Clinical, Virologic, and Epidemiologic Characteristics of Dengue Outbreak, Dar es Salaam, Tanzania, 2014.

    Science.gov (United States)

    Vairo, Francesco; Mboera, Leonard E G; De Nardo, Pasquale; Oriyo, Ndekya M; Meschi, Silvia; Rumisha, Susan F; Colavita, Francesca; Mhina, Athanas; Carletti, Fabrizio; Mwakapeje, Elibariki; Capobianchi, Maria Rosaria; Castilletti, Concetta; Di Caro, Antonino; Nicastri, Emanuele; Malecela, Mwelecele N; Ippolito, Giuseppe

    2016-05-01

    We investigated a dengue outbreak in Dar es Salaam, Tanzania, in 2014, that was caused by dengue virus (DENV) serotype 2. DENV infection was present in 101 (20.9%) of 483 patients. Patient age and location of residence were associated with infection. Seven (4.0%) of 176 patients were co-infected with malaria and DENV.

  17. Saltwater intrusion in the quaternary aquifer of the Dar es Salaam region, Tanzania

    OpenAIRE

    Mtoni, Y.; Walraevens, K.

    2010-01-01

    Groundwater is a last-resort source of domestic water supply in Dar es Salaam City because of the scarcity of surface water sources. The Tanzania Government, Non Government Organizations (NGOs), Community Based Organizations (CBOs) and international aid organizations have promoted the drilling of boreholes. From 1997 until the present, boreholes drilling has increased tremendously and the trend is expected to increase even more in the future. Initial assessment of the current state of water q...

  18. Assessment of human thermal perception in the hot-humid climate of Dar es Salaam, Tanzania

    Science.gov (United States)

    Ndetto, Emmanuel L.; Matzarakis, Andreas

    2017-01-01

    Dar es Salaam, Tanzania, is a typical African city along the Indian Ocean coast, and therefore an important urban area to examine human thermal perception in the hot-humid tropical climate. Earlier research on human bioclimate at Dar es Salaam indicated that heat stress prevails during the hot season from October to March, peaking between December and February, particularly the early afternoons. In order to assess the human thermal perception and adaptation, two popular places, one at an urban park and another at a beach environment, were selected and questionnaire surveys were conducted in August-September 2013 and January 2014, concurrently with local micro-meteorological measurements at survey locations. The thermal conditions were quantified in terms of the thermal index of the physiologically equivalent temperature (PET) using the micro-scale climate model RayMan. The thermal comfort range of human thermal comfort and the local thermal adaptive capacity were determined in respect to the thermal index by binning thermal sensation votes. The thermal comfort range was found to be well above that in temperate climates at about 23-31 °C of PET. The study could significantly contribute to urban planning in Dar es Salaam and other coastal cities in the tropics.

  19. Assessment of human thermal perception in the hot-humid climate of Dar es Salaam, Tanzania

    Science.gov (United States)

    Ndetto, Emmanuel L.; Matzarakis, Andreas

    2016-06-01

    Dar es Salaam, Tanzania, is a typical African city along the Indian Ocean coast, and therefore an important urban area to examine human thermal perception in the hot-humid tropical climate. Earlier research on human bioclimate at Dar es Salaam indicated that heat stress prevails during the hot season from October to March, peaking between December and February, particularly the early afternoons. In order to assess the human thermal perception and adaptation, two popular places, one at an urban park and another at a beach environment, were selected and questionnaire surveys were conducted in August-September 2013 and January 2014, concurrently with local micro-meteorological measurements at survey locations. The thermal conditions were quantified in terms of the thermal index of the physiologically equivalent temperature (PET) using the micro-scale climate model RayMan. The thermal comfort range of human thermal comfort and the local thermal adaptive capacity were determined in respect to the thermal index by binning thermal sensation votes. The thermal comfort range was found to be well above that in temperate climates at about 23-31 °C of PET. The study could significantly contribute to urban planning in Dar es Salaam and other coastal cities in the tropics.

  20. Numerical simulation of groundwater flow in Dar es Salaam Coastal Plain (Tanzania)

    Science.gov (United States)

    Luciani, Giulia; Sappa, Giuseppe; Cella, Antonella

    2016-04-01

    They are presented the results of a groundwater modeling study on the Coastal Aquifer of Dar es Salaam (Tanzania). Dar es Salaam is one of the fastest-growing coastal cities in Sub-Saharan Africa, with with more than 4 million of inhabitants and a population growth rate of about 8 per cent per year. The city faces periodic water shortages, due to the lack of an adequate water supply network. These two factors have determined, in the last ten years, an increasing demand of groundwater exploitation, carried on by quite a number of private wells, which have been drilled to satisfy human demand. A steady-state three dimensional groundwater model has been set up by the MODFLOW code, and calibrated with the UCODE code for inverse modeling. The aim of the model was to carry out a characterization of groundwater flow system in the Dar es Salaam Coastal Plain. The inputs applied to the model included net recharge rate, calculated from time series of precipitation data (1961-2012), estimations of average groundwater extraction, and estimations of groundwater recharge, coming from zones, outside the area under study. Parametrization of the hydraulic conductivities was realized referring to the main geological features of the study area, based on available literature data and information. Boundary conditions were assigned based on hydrogeological boundaries. The conceptual model was defined in subsequent steps, which added some hydrogeological features and excluded other ones. Calibration was performed with UCODE 2014, using 76 measures of hydraulic head, taken in 2012 referred to the same season. Data were weighted on the basis of the expected errors. Sensitivity analysis of data was performed during calibration, and permitted to identify which parameters were possible to be estimated, and which data could support parameters estimation. Calibration was evaluated based on statistical index, maps of error distribution and test of independence of residuals. Further model

  1. Storage, Collection and Disposal of Kariakoo Market Wastes in Dar Es Salaam, Tanzania

    DEFF Research Database (Denmark)

    Yhdego, Michael

    1992-01-01

    In many developing countries, the market is still the most important source of commerce for traders and provisions for the general public. The transmission of disease in the market place involves factors relating to the host, the agent and the environment. This study examines the quality of solid...... waste management in Kariakoo market, Dar es Salaam. The main problems identified were poor market design and lack of a well organized waste storage, collection and disposal systems. Two-thirds of the waste consists of vegetable matter. Proposals for improved design of storage and collection facilities...

  2. The use of social media among adolescents in Dar es Salaam and Mtwara, Tanzania.

    Science.gov (United States)

    Pfeiffer, Constanze; Kleeb, Matthis; Mbelwa, Alice; Ahorlu, Collins

    2014-05-01

    Social media form part of the rapid worldwide digital development that is re-shaping the life of many young people. While the use of social media by youths is increasingly researched in the North, studies about youth in the South are missing. It therefore remains unclear how social media can be included in interventions that aim at informing young people in many countries of the global South about sexual and reproductive health. This paper presents findings of a mixed-methods study of young people's user behaviour on the internet and specifically of social media as a platform for sexual health promotion in Tanzania. The study used questionnaires with 60 adolescents and in-depth interviews with eight students aged 15 to 19 years in Dar es Salaam, and in Mtwara, Southern Tanzania. Findings show that youth in Dar es Salaam and Mtwara access the internet mainly through mobile phones. Facebook is by far the most popular internet site. Adolescents highlighted their interest in reproductive and sexual health messages and updates being delivered through humorous posts, links and clips, as well as by youth role models like music stars and actors that are entertaining and reflect up-to-date trends of modern youth culture.

  3. Body-art practices among undergraduate medical university students in Dar Es Salaam, Tanzania, 2014

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    Chacha Emmanuel Chacha

    2015-01-01

    Full Text Available Background: Body-art practices are increasing among adolescents and young adults. Although substantial data are available in developed countries, little has been documented about body-art practices in developing countries. Objective: To determine the magnitude, types and reasons for practicing body-art practices among undergraduate medical University students in Dar es Salaam, Tanzania. Materials and Methods: A cross-sectional descriptive study was conducteed among undergraduate University students in Dar es Salaam involving 536 respondents from two Universities. We used a self-administered questionnaire to collect data. Analyses were based on summary measures and bivariate analyses. Results: While 7.5% of undergraduate students reported having tattoos, 20% reported having body puncturing or piercing. Body piercing is reported more among female university undergraduate students than their male counterparts. Reported main reasons for undergoing body-art include "a mark of beauty," 24%, "just wanted one," 18% and "a mark of femininity or masculinity," 17%. The majority (98% of students were aware that unsafe body-art practices may lead to contracting HIV and more than half (52% reported awareness of the risk of Hepatitis B infection. Conclusions: Despite high awareness of the potential risks involved in unsafe body arts that include tattoo and piercing, these practices are increasing among adolescents and young adults. There is need to have educational and counseling efforts so as to minimize associated health risks.

  4. Modeling Urban Growth Spatial Dynamics: Case studies of Addis Ababa and Dar es Salaam

    Science.gov (United States)

    Buchta, Katja; Abo El Wafa, Hany; Printz, Andreas; Pauleit, Stephan

    2013-04-01

    Rapid urbanization, and consequently, the dramatic spatial expansion of mostly informal urban areas increases the vulnerability of African cities to the effects of climate change such as sea level rise, more frequent flooding, droughts and heat waves. The EU FP 7 funded project CLUVA (Climate Change and Urban Vulnerability in Africa, www.cluva.eu) aims to develop strategies for minimizing the risks of natural hazards caused by climate change and to improve the coping capacity of African cities. Green infrastructure may play a particular role in climate change adaptation by providing ecosystem services for flood protection, stormwater retention, heat island moderation and provision of food and fuel wood. In this context, a major challenge is to gain a better understanding of the spatial and temporal dynamics of the cities and how these impact on green infrastructure and hence their vulnerability. Urban growth scenarios for two African cities, namely Addis Ababa, Ethiopia and Dar es Salaam, Tanzania, were developed based on a characterization of their urban morphology. A population growth driven - GIS based - disaggregation modeling approach was applied. Major impact factors influencing the urban dynamics were identified both from literature and interviews with local experts. Location based factors including proximity to road infrastructure and accessibility, and environmental factors including slope, surface and flood risk areas showed a particular impact on urban growth patterns. In Addis Ababa and Dar es Salaam, population density scenarios were modeled comparing two housing development strategies. Results showed that a densification scenario significantly decreases the loss of agricultural and green areas such as forests, bushland and sports grounds. In Dar es Salaam, the scenario of planned new settlements with a population density of max. 350 persons per hectare would lead until 2025 to a loss of agricultural land (-10.1%) and green areas (-6.6%). On the other

  5. Demand for orthodontic treatment among 9-18 year-olds seeking dental care in Dar-es-Salaam, Tanzania.

    NARCIS (Netherlands)

    Mugonzibwa, E.A.; Kuijpers-Jagtman, A.M.; Hof, M.A. van 't; Kikwilu, E.

    2004-01-01

    OBJECTIVE: To investigate the demand for orthodontic treatment among 9-18 olds seeking dental care in Dar-es-Salaam, Tanzania. DESIGN: Case-control, interview and clinical study. SETTINGS: Children seeking dental care. MAIN OUTCOME MEASURES: Demand for orthodontic treatment. RESULTS: Most of the chi

  6. Pit Latrine Emptying Behavior and Demand for Sanitation Services in Dar Es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Marion W. Jenkins

    2015-02-01

    Full Text Available Pit latrines are the main form of sanitation in unplanned areas in many rapidly growing developing cities. Understanding demand for pit latrine fecal sludge management (FSM services in these communities is important for designing demand-responsive sanitation services and policies to improve public health. We examine latrine emptying knowledge, attitudes, behavior, trends and rates of safe/unsafe emptying, and measure demand for a new hygienic latrine emptying service in unplanned communities in Dar Es Salaam (Dar, Tanzania, using data from a cross-sectional survey at 662 residential properties in 35 unplanned sub-wards across Dar, where 97% had pit latrines. A picture emerges of expensive and poor FSM service options for latrine owners, resulting in widespread fecal sludge exposure that is likely to increase unless addressed. Households delay emptying as long as possible, use full pits beyond what is safe, face high costs even for unhygienic emptying, and resort to unsafe practices like ‘flooding out’. We measured strong interest in and willingness to pay (WTP for the new pit emptying service at 96% of residences; 57% were WTP ≥U.S. $17 to remove ≥200 L of sludge. Emerging policy recommendations for safe FSM in unplanned urban communities in Dar and elsewhere are discussed.

  7. Climate change induced risk analysis of Dar es Salaam city (Tanzania)

    Science.gov (United States)

    Topa, Maria Elena; Herslund, Lise; Cavan, Gina; Printz, Andreas; Simonis, Ingo; Bucchignani, Edoardo; Jean-Baptiste, Nathalie; Hellevik, Siri; Johns, Regina; Kibassa, Deusdedit; Kweka, Clara; Magina, Fredrick; Mangula, Alpha; Mbuya, Elinorata; Uhinga, Guido; Kassenga, Gabriel; Kyessi, Alphonce; Shemdoe, Riziki; Kombe, Wilbard

    2013-04-01

    CLUVA (CLimate change and Urban Vulnerability in Africa; http://www.cluva.eu/) is a 3 years project, funded by the European Commission in 2010. The main objective of CLUVA is to develop context-centered methods and knowledge to be applied to African cities to assess vulnerabilities and increase knowledge on managing climate related risks. The project estimates the impacts of climate changes in the next 40 years at urban scale and downscales IPCC climate projections to evaluate specific threats to selected African test cities. These are mainly from floods, sea-level rise, droughts, heat waves, and desertification. The project evaluates and links: social vulnerability; urban green structures and ecosystem services; urban-rural interfaces; vulnerability of urban built environment and lifelines; and related institutional and governance dimensions of adaptation. The multi-scale and multi-disciplinary qualitative, quantitative and probabilistic approach of CLUVA is currently being applied to selected African test cities (Addis Ababa - Ethiopia; Dar es Salaam - Tanzania; Douala - Cameroun; Ouagadougou - Burkina Faso; St. Louis - Senegal). In particular, the poster will present preliminary findings for the Dar es Salaam case study. Dar es Salaam, which is Tanzania's largest coastal city, is exposed to floods, coastal erosion, droughts and heat waves, and highly vulnerable to impacts as a result of ineffective urban planning (about 70% unplanned settlements), poverty and lack of basic infrastructure (e.g. lack of or poor quality storm water drainage systems). Climate change could exacerbate the current situation increasing hazard-exposure alongside the impacts of development pressures which act to increase urban vulnerability for example because of informal (unregulated) urbanization. The CLUVA research team - composed of climate and environmental scientists, risk management experts, urban planners and social scientists from both European and African institutions - has

  8. The role of local government in promoting sustainable urban agriculture in Dar es Salaam and Copenhagen

    DEFF Research Database (Denmark)

    Halloran, Afton Marian Szasz; Magid, Jakob

    2013-01-01

    As a multifunctional activity and land use, urban agriculture supports a range of objectives, from urban greening to food security. However, it is often left out of urban policy. As a result of the highly contextual and cross-cutting nature of urban agriculture, there are relatively few...... comprehensive and formalized regulatory tools to draw from. Different cities around the world are now deciding how to fit urban agriculture into the urban agenda; however, in many places urban agriculture continues to operate in the absence of legitimization due to its relatively mobile and dynamic nature....... This article looks at the importance of local and central governments in promoting sustainable urban agriculture. Through participatory action research, it examines the cases of Dar es Salaam, Tanzania and Copenhagen, Denmark to understand stakeholder interactions, as well as present and future barriers...

  9. BUS BAY PERFORMANCE AND ITS INFLUENCE ON THE CAPACITY OF ROAD NETWORK IN DAR ES SALAAM

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    Nurdin K. Mushule

    2012-01-01

    Full Text Available One of major problems facing motorists in Dar es Salaam city today is congestion. Bus bays have a significant influence on the capacity of a roadway because they interfere with passing vehicles primarily when buses maneuver to pull into and out of bus bays. Bus bay stops will also interfere with vehicles movement if bus demand exceeds the bus bay capacity resulting in some buses waiting in the travel lane until the buses occupying the bay exit the bay. This paper presents the results of a study which was carried out to evaluate the bus bay performance and its influence on the capacity of the roadway network in the city of Dar es Salaam. The case study area covered 11 bus stops along Morogoro road from Ubungo to Magomeni Mapipa. Capacity of bus bays was studied using procedure outlined in the Transit Capacity and Quality of Service Manual of 2003. This enabled the researcher to determine parameters such as dwell times and clearance times which are major determinants of bus stop capacity. The results indicate that only 18% of the bus bay stops studied did not have adequate capacity to cater for the available demand. 9% did not have adequate capacity during peak hours but the capacity was adequate during off-peak hours. The remaining 73% of bus bay stops possess adequate capacity all the time. Although most bus bay stops studied possess adequate capacity, severe congestion was observed at these locations. This is due to erratic behavior of bus drivers who do not utilize the provided space for them to drop off and pick up passengers. Clearly, this is an area that requires more strict enforcement in order to ease the congestion problem in the city by operating the existing capacity more efficiently."

  10. Identification of diarrheagenic Escherichia coli isolated from infants and children in Dar es Salaam, Tanzania

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    Matee Mecky I

    2007-08-01

    Full Text Available Abstract Background Relatively few studies have been done in Tanzania to detect and classify diarrheagenic Escherichia coli (DEC strains among children with diarrhea. This study aimed at investigating DEC among children in Dar es Salaam aged less than five years hospitalized due to acute/persistent diarrhea. Methods DEC were isolated from stool samples collected from two hundred and eighty children with acute/persistent diarrhea at Muhimbili National Hospital and Ilala and Mwananyamala Municipal Hospitals in Dar es Salaam. A multiplex PCR system method was used to detect a species specific gene for E.coli and ten different virulence genes for detection of five pathogroups of DEC namely enteroaggregative- (EAEC, enteropathogenic- (EPEC, enterotoxigenic- (ETEC, enteroinvasive- (EIEC and enterohemorghagic- Escherichia coli (EHEC. Results Sixty-four patients (22.9% harbored DEC. Forty-one of them (14.6% were categorized as EAEC. Most of the EAEC (82.9% were classified as typical EAEC possessing the aggR gene, and 92.6% carried the aat gene. Isolates from thirteen patients were EPEC (4.6% and most of these (92.3% were typical EPEC with both eae and bfpA genes. Ten isolates were identified as ETEC (3.6% with only the heat stable toxin; either st1a or st1b but not both. Age wise, EAEC and EPEC were significantly more prevalent among the age group 0–6 months (p stx1 and stx2 and EIEC (ial were not detected in this study group. Conclusion The results show a high proportion of DEC among Tanzanian children with diarrhea, with typical EAEC and typical EPEC predominating. The use of primers for both variants of ST1 (st1a and st1b increased the sensitivity for detection of ETEC strains.

  11. Qatar Airways Touches Down in Dar es Salaam Airline Launches First Route Of 2007 To Tanzania's Commercial Hub Award-Winning Carrier Expands Operations In Africa

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Qatar Airways has celebrated the launch of its first new route of 2007 with its inaugural flight to Tanzania touching down in the country's commercial capital of Dar es Salaam to a fanfare of music and dance.

  12. Prevalence, Perceived Factors and Knowledge on Effects of Tobacco Use on Oral Health Among Secondary School Students in Dar es salaam

    OpenAIRE

    Kabulwa, Msafiri Nicodemus

    2011-01-01

    At the time of the conception of this study there was scant information on self reported prevalence, knowledge on detrimental effects on oral health and factors influencing tobacco use among secondary school students in Dar es Salaam region. To determine the prevalence, perceived factors that may lead and /or deter secondary school students to use tobacco and knowledge on effects of tobacco use on oral health among secondary school students in Dar es Salaam. This was a descriptive cross-secti...

  13. Informal urban settlements and cholera risk in Dar es Salaam, Tanzania.

    Directory of Open Access Journals (Sweden)

    Katherine Penrose

    Full Text Available BACKGROUND: As a result of poor economic opportunities and an increasing shortage of affordable housing, much of the spatial growth in many of the world's fastest-growing cities is a result of the expansion of informal settlements where residents live without security of tenure and with limited access to basic infrastructure. Although inadequate water and sanitation facilities, crowding and other poor living conditions can have a significant impact on the spread of infectious diseases, analyses relating these diseases to ongoing global urbanization, especially at the neighborhood and household level in informal settlements, have been infrequent. To begin to address this deficiency, we analyzed urban environmental data and the burden of cholera in Dar es Salaam, Tanzania. METHODOLOGY/PRINCIPAL FINDINGS: Cholera incidence was examined in relation to the percentage of a ward's residents who were informal, the percentage of a ward's informal residents without an improved water source, the percentage of a ward's informal residents without improved sanitation, distance to the nearest cholera treatment facility, population density, median asset index score in informal areas, and presence or absence of major roads. We found that cholera incidence was most closely associated with informal housing, population density, and the income level of informal residents. Using data available in this study, our model would suggest nearly a one percent increase in cholera incidence for every percentage point increase in informal residents, approximately a two percent increase in cholera incidence for every increase in population density of 1000 people per km(2 in Dar es Salaam in 2006, and close to a fifty percent decrease in cholera incidence in wards where informal residents had minimally improved income levels, as measured by ownership of a radio or CD player on average, in comparison to wards where informal residents did not own any items about which they were

  14. Air pollution by motor traffic in Dar-es-Salaam. Measurements and state of the art description

    Energy Technology Data Exchange (ETDEWEB)

    Henricson, Daniel

    1999-06-01

    Dar-es-Salaam was the capital of Tanzania until 1973, when it was moved to Dodoma. The city is still the largest and holds about 1.6 million inhabitants. The aim of the project is to measure air pollution from traffic close to people and set a foundation for future studies. Besides that finding ways to reduce air pollution and improve traffic situation in Dar-es-Salaam with an emphasis on the central city parts. Previous studies on air pollution in Dar-es-Salaam have all been rather rushed and mostly with old and not very precise equipment. For that reason you could say this project is like a pilot study. Measurements were made on NO, NO{sub 2}, SO{sub 2}, O{sub 3}, and VOC (hydrocarbons) during two different measuring weeks. Average temperature, wind velocity and traffic flow was measured on both weeks. Traffic flow was 12 000 vehicles/day. The percentage of accelerating/retarding vehicles and average speed was also studied. Average speed was 20 km/h. The result above show levels somewhat exceeding the guidelines. The levels can not be said to be alarmingly high, but bearing the rapid increase in the number of vehicles in mind, air pollution will soon be a major problem. It would have been preferred to also measure lead, particles and carbon monoxide, especially particles since previous reports indicates very high levels. To create a better air quality in Dar-es-Salaam there has to be an improvement of public transport and at the same time increased parking fees and fuel prices. Finally, fuel quality has to improve and unleaded petrol has to be introduced as soon as possible 10 refs, 4 figs, 15 tabs

  15. Efficacy of Waterless Hand Hygiene Compared with Handwashing with Soap: A Field Study in Dar es Salaam, Tanzania

    OpenAIRE

    Pickering, Amy J.; Boehm, Alexandria B.; Mwanjali, Mathew; Davis, Jennifer

    2010-01-01

    Effective handwashing with soap requires reliable access to water supplies. However, more than three billion persons do not have household-level access to piped water. This research addresses the challenge of improving hand hygiene within water-constrained environments. The antimicrobial efficacy of alcohol-based hand sanitizer, a waterless hand hygiene product, was evaluated and compared with handwashing with soap and water in field conditions in Dar es Salaam, Tanzania. Hand sanitizer use b...

  16. Medicalization and morality in a weak state: health, hygiene and water in Dar Es Salaam, Tanzania.

    Science.gov (United States)

    Obrist, Brigit

    2004-04-01

    Inspired by Foucault, many studies have examined the medicalization of everyday life in Western societies. This paper reconsiders potentials and limitations of this concept in an African city. Grounded in ethnographic research in Dar es Salaam, Tanzania, it concentrates on cleanliness, health and water in a lower middle-class neighbourhood. The findings show that women are familiar with professional health development discourses emphasizing cleanliness as a high value linked to bodily and domestic health. These discourses have been diffused in schools, clinics and other institutions during the colonial and socialist period. Women not only refer to these discourses, they try to reproduce them in daily practice and even demand them. This coercive yet voluntary nature of institutionalized discourses points to 'paradoxes of medicalization' also found in Western societies. It acquires, however, different meanings in a weak state like contemporary Tanzania which hardly manages to institutionalize medicalization through professional practice. Under such conditions, women who choose to follow health development discourses suffer a heavier practical, intellectual and emotional burden than those who are less committed. This may at least partly explain why many women assume a pragmatic stance towards the medicalization of everyday life.

  17. Assessing urban fire risk in the central business district of Dar es Salaam, Tanzania

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    Yohannes Kachenje

    2010-04-01

    Full Text Available Buildings as infrastructure along with people’s lives need protection against fire outbreaks. Knowledge on the use of installed facilities is essential in tackling There emergencies, otherwise their installation becomes meaningless. Lack of such knowledge could hamper escape from There hazards and thwart attempts to contain there outbreaks at their preliminary stage. THis study, carried out in the Central Business District of Dar es Salaam City, assessed urban there risk with respect to public awareness on the use of #re #ghting facilities and preparedness in the event of #re outbreaks. Public buildings with at least four storeys or 2000m2 floor space were surveyed. According to the Fire and Rescue Act of 2007, such buildings have to be provided with adequate means of escape and #re #ghting facilities. Data was collected through observation and interviews with building managers, users and key informants. The study revealed high there disaster risk in most buildings of the study area, as 60% of the buildings’ users do not know how to operate the facilities, and 41% are not aware of the available escape means in case of there outbreak. Worse still, only 29% had received training within the past five years, and 68% had never been trained.

  18. Nutrient and Phytoplankton Dynamics along the Ocean Road Sewage Discharge Channel, Dar es Salaam, Tanzania

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    Mariam I. Hamisi

    2014-01-01

    Full Text Available Ocean Road shoreline is situated close to Dar es Salaam largest fish market and is subjected to sewage discharge. In this study, temporal and spatial variations of physicochemical parameters and phytoplankton were studied in five stations along the Ocean Road Coast. Phytoplankton composition, temperature, dissolved oxygen (DO, salinity, water clarity, pH, and dissolved inorganic nutrients (DIN including nitrite, nitrate, and phosphate were measured. Results revealed that DIN were significantly higher in the station close to the discharge point than other stations (P<0.0001. There were no significant temporal variations in DIN except nitrate that was significantly higher during Northeast Monsoon than Southeast Monsoon (P<0.001. Other environmental parameters showed no significant differences except clarity, conductivity, and DO. Occurrence of potential harmful species such as Trichodesmium, Microcystis, and Pseudo-nitzschia was observed. The phytoplankton biomass (chlorophyll a ranged from 3.2 to 56.5 mg m−3 and 18 to 113 mg m−3 for Mjimwema (MJ and Ocean Road (OR stations, respectively. There was significant difference (P=0.0033 in chlorophyll a among the stations being higher in OR II. The phytoplankton biomass was positively correlated with nutrient concentration in all stations except OR I. This study suggests an alarming level of DIN at OR that may alter phytoplankton biomass, abundance, and composition.

  19. Patterns of sexually transmitted infections in adolescents and youth in Dar es Salaam, Tanzania

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    Swai Andrew

    2006-02-01

    Full Text Available Abstract Background Syndromic management of STIs has been advocated as simplified and cheap approach. Youth have been reported to be at increased risk of acquiring STIs which can facilitate HIV transmission. We have investigated the relationship between the syndromic management and specific aetiology diagnosis and its relationship with HIV infection and health seeking behaviour among youth attending a reproductive health clinic in Dar es Salaam, Tanzania. Methods Between September 1998 and February 1999 among 1895 adolescents and youth below 25 years seen in the clinic 199 (10.5% were randomly selected and consented to participate in the study. A standard questionnaire was administered. Blood and vaginal or urethral specimens were taken and investigated for STI causative agents. Results Among a total of 199 studied adolescents and youth 22.6 % were teenagers, with fewer females 17.8% than males; 27.5% (p Conclusion The burden of STIs in this youth population is large indicating that youth are at increased risk of STIs and will certainly require youth friendly clinics. There is a need to refine the current syndromic management guidelines.

  20. CHARACTERIZATION OF SALMONELLA SPECIES FROM WATER BODIES IN DAR-ES-SALAAM CITY, TANZANIA

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    Eliningaya Kweka

    2013-03-01

    Full Text Available Background: Water-borne diseases are the most common cause of illness and death among the poor population from developing countries. The majority of the people are inadequately aware that aquatic environment is a major source of salmonellosis. Dar es Salaam city is among the cities with most of its population live in squatter. Typhoid fever ranks second with 14.3% of all notifiable disease cases in the city. The city experience water scarcity which forces water wells and rivers to become the main sources of water for domestic use and livestock. This study therefore, characterized Salmonella strains from different water bodies of city as possible sources for enteric diseases endemicity. Methods: The Salmonella Chromogenic Agar (SC Agar and Kligler Iron Agar (KIA media were used for isolation and enumeration of the strains. The inoculated cultures were incubated at 370C for 24 hours. Salmonella colonies were confirmed by magenta colorations and hydrogen sulfide production on SC Agar and KIA Agar, respectively. The Analytical Profile Index 20 Enterobacteriaceae kit (API 20E kit was used to identify Salmonella species. Results: Based on the API 20E kit, the identified Salmonella species from different water bodies were Salmonella ser. paratyphi A (96.9%, Salmonella cholelaesuis spp choleraesuis (99.5% and Salmonella typhi (99.9%. Conclusion: This study shows that shallow wells and rivers which are mainly used by the city dwellers were highly contaminated with Salmonella and were more contaminated than deep wells and marine water bodies. This warrants further investigation on the disease mapping in the urban and peri-urban areas.

  1. Microbial Efficacy of Waterless Hand Hygiene in Dar es Salaam, Tanzania

    Science.gov (United States)

    Pickering, A.; Boehm, A.; Davis, J.

    2008-12-01

    Millions of people die from diarrheal and respiratory diseases every year due to lack of proper sanitation, hygiene, and access to clean water. The act of handwashing with soap has been found to effectively reduce both diarrheal and respiratory illness, however, handwashing at critical times (i.e. after using the toilet, before preparing food) remains infrequent around the world. This research investigates the potential for alcohol- based hand sanitizer (ABHS) to be an effective and appropriate hand hygiene option in developing countries. A study was conducted to assess the microbiological effectiveness of ABHS, as compared to handwashing with soap and water, in field conditions in Dar es Salaam, Tanzania. A total of 205 participants, including mothers, nurses, students, and teachers, were introduced to ABHS, given a standardized amount (2ml) of product, and instructed on how to use the product correctly. Hand samples were obtained using the hand rinse method before and after the use of ABHS from 152 participants. The other 53 participants were hand sampled before and after handwashing with a non-antimicrobial liquid soap and clean water (prior to using ABHS). Visual inspections of the hands were performed before hand sampling to record the level of dirt on the hands. All hand samples were processed and analyzed by membrane filtration for concentrations of two microbial indicators, enterococci and E. coli. User perceptions of the product and willingness to pay are also documented. The results of this study provide valuable insight on the prospective of promoting ABHS in developing countries and water scarce areas.

  2. Interdependence of domestic malaria prevention measures and mosquito-human interactions in urban Dar es Salaam, Tanzania

    Science.gov (United States)

    Geissbühler, Yvonne; Chaki, Prosper; Emidi, Basiliana; Govella, Nicodemus J; Shirima, Rudolf; Mayagaya, Valeliana; Mtasiwa, Deo; Mshinda, Hassan; Fillinger, Ulrike; Lindsay, Steven W; Kannady, Khadija; de Castro, Marcia Caldas; Tanner, Marcel; Killeen, Gerry F

    2007-01-01

    Background Successful malaria vector control depends on understanding behavioural interactions between mosquitoes and humans, which are highly setting-specific and may have characteristic features in urban environments. Here mosquito biting patterns in Dar es Salaam, Tanzania are examined and the protection against exposure to malaria transmission that is afforded to residents by using an insecticide-treated net (ITN) is estimated. Methods Mosquito biting activity over the course of the night was estimated by human landing catch in 216 houses and 1,064 residents were interviewed to determine usage of protection measures and the proportion of each hour of the night spent sleeping indoors, awake indoors, and outdoors. Results Hourly variations in biting activity by members of the Anopheles gambiae complex were consistent with classical reports but the proportion of these vectors caught outdoors in Dar es Salaam was almost double that of rural Tanzania. Overall, ITNs confer less protection against exophagic vectors in Dar es Salaam than in rural southern Tanzania (59% versus 70%). More alarmingly, a biting activity maximum that precedes 10 pm and much lower levels of ITN protection against exposure (38%) were observed for Anopheles arabiensis, a vector of modest importance locally, but which predominates transmission in large parts of Africa. Conclusion In a situation of changing mosquito and human behaviour, ITNs may confer lower, but still useful, levels of personal protection which can be complemented by communal transmission suppression at high coverage. Mosquito-proofing houses appeared to be the intervention of choice amongst residents and further options for preventing outdoor transmission include larviciding and environmental management. PMID:17880679

  3. Interdependence of domestic malaria prevention measures and mosquito-human interactions in urban Dar es Salaam, Tanzania

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    Mshinda Hassan

    2007-09-01

    Full Text Available Abstract Background Successful malaria vector control depends on understanding behavioural interactions between mosquitoes and humans, which are highly setting-specific and may have characteristic features in urban environments. Here mosquito biting patterns in Dar es Salaam, Tanzania are examined and the protection against exposure to malaria transmission that is afforded to residents by using an insecticide-treated net (ITN is estimated. Methods Mosquito biting activity over the course of the night was estimated by human landing catch in 216 houses and 1,064 residents were interviewed to determine usage of protection measures and the proportion of each hour of the night spent sleeping indoors, awake indoors, and outdoors. Results Hourly variations in biting activity by members of the Anopheles gambiae complex were consistent with classical reports but the proportion of these vectors caught outdoors in Dar es Salaam was almost double that of rural Tanzania. Overall, ITNs confer less protection against exophagic vectors in Dar es Salaam than in rural southern Tanzania (59% versus 70%. More alarmingly, a biting activity maximum that precedes 10 pm and much lower levels of ITN protection against exposure (38% were observed for Anopheles arabiensis, a vector of modest importance locally, but which predominates transmission in large parts of Africa. Conclusion In a situation of changing mosquito and human behaviour, ITNs may confer lower, but still useful, levels of personal protection which can be complemented by communal transmission suppression at high coverage. Mosquito-proofing houses appeared to be the intervention of choice amongst residents and further options for preventing outdoor transmission include larviciding and environmental management.

  4. Window screening, ceilings and closed eaves as sustainable ways to control malaria in Dar es Salaam, Tanzania

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    Chaki Prosper P

    2009-09-01

    Full Text Available Abstract Background Malaria transmission in Africa occurs predominantly inside houses where the primary vectors prefer to feed. Human preference and investment in blocking of specific entry points for mosquitoes into houses was evaluated and compared with known entry point preferences of the mosquitoes themselves. Methods Cross-sectional household surveys were conducted in urban Dar es Salaam, Tanzania to estimate usage levels of available options for house proofing against mosquito entry, namely window screens, ceilings and blocking of eaves. These surveys also enabled evaluation of household expenditure on screens and ceilings and the motivation behind their installation. Results Over three quarters (82.8% of the 579 houses surveyed in Dar es Salaam had window screens, while almost half (48.9% had ceilings. Prevention of mosquito entry was cited as a reason for installation of window screens and ceilings by 91.4% (394/431 and 55.7% (127/228 of respondents, respectively, but prevention of malaria was rarely cited (4.3%, 22/508. The median cost of window screens was between US $ 21-30 while that of ceilings was between US $301-400. The market value of insecticide-treated nets, window screening and ceilings currently in use in the city was estimated as 2, 5 and 42 million US$. More than three quarters of the respondents that lacked them said it was too expensive to install ceilings (82.2% or window screens (75.5%. Conclusion High coverage and spending on screens and ceilings implies that these techniques are highly acceptable and excellent uptake can be achieved in urban settings like Dar es Salaam. Effective models for promotion and subsidization should be developed and evaluated, particularly for installation of ceilings that prevent entry via the eaves, which are the most important entry point for mosquitoes that cause malaria, a variety of neglected tropical diseases and the nuisance which motivates uptake.

  5. The Risk of Dengue Virus Transmission in Dar es Salaam, Tanzania during an Epidemic Period of 2014.

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    Leonard E G Mboera

    2016-01-01

    Full Text Available In 2010, 2012, 2013 and 2014 dengue outbreaks have been reported in Dar es Salaam, Tanzania. However, there is no comprehensive data on the risk of transmission of dengue in the country. The objective of this study was to assess the risk of transmission of dengue in Dar es Salaam during the 2014 epidemic.This cross-sectional study was conducted in Dar es Salaam, Tanzania during the dengue outbreak of 2014. The study involved Ilala, Kinondoni and Temeke districts. Adult mosquitoes were collected using carbon dioxide-propane powered Mosquito Magnet Liberty Plus traps. In each household compound, water-holding containers were examined for mosquito larvae and pupae. Dengue virus infection of mosquitoes was determined using real-time reverse transcription polymerase chain reaction (qRT-PCR. Partial amplification and sequencing of dengue virus genome in infected mosquitoes was performed. A total of 1,000 adult mosquitoes were collected. Over half (59.9% of the adult mosquitoes were collected in Kinondoni. Aedes aegypti accounted for 17.2% of the mosquitoes of which 90.6% were from Kinondoni. Of a total of 796 houses inspected, 38.3% had water-holding containers in their premises. Kinondoni had the largest proportion of water-holding containers (57.7%, followed by Temeke (31.4% and Ilala (23.4%. The most common breeding containers for the Aedes mosquitoes were discarded plastic containers and tires. High Aedes infestation indices were observed for all districts and sites, with a house index of 18.1% in Ilala, 25.5% in Temeke and 35.3% in Kinondoni. The respective container indices were 77.4%, 65.2% and 80.2%. Of the reared larvae and pupae, 5,250 adult mosquitoes emerged, of which 61.9% were Ae. aegypti. Overall, 27 (8.18 of the 330 pools of Ae. aegypti were positive for dengue virus. On average, the overall maximum likelihood estimate (MLE indicates pooled infection rate of 8.49 per 1,000 mosquitoes (95%CI = 5.72-12.16. There was no significant

  6. Masculine attitudes of superiority deter men from accessing antiretroviral therapy in Dar es Salaam, Tanzania

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    Tumaini M. Nyamhanga

    2013-10-01

    Full Text Available Background: This article presents part of the findings from a larger study that sought to assess the role that gender relations play in influencing equity regarding access and adherence to antiretroviral therapy (ART. Review of the literature has indicated that, in Southern and Eastern Africa, fewer men than women have been accessing ART, and the former start using ART late, after HIV has already been allowed to advance. The main causes for this gender gap have not yet been fully explained. Objective: To explore how masculinity norms limit men's access to ART in Dar es Salaam. Design: This article is based on a qualitative study that involved the use of focus group discussions (FGDs. The study employed a stratified purposive sampling technique to recruit respondents. The study also employed a thematic analysis approach. Results: Overall, the study's findings revealed that men's hesitation to visit the care and treatment clinics signifies the superiority norm of masculinity that requires men to avoid displaying weakness. Since men are the heads of families and have higher social status, they reported feeling embarrassed at having to visit the care and treatment clinics. Specifically, male respondents indicated that going to a care and treatment clinic may raise suspicion about their status of living with HIV, which in turn may compromise their leadership position and cause family instability. Because of this tendency towards ‘hiding’, the few men who register at the public care and treatment clinics do so late, when HIV-related signs and symptoms are already far advanced. Conclusion: This study suggests that the superiority norm of masculinity affects men's access to ART. Societal expectations of a ‘real man’ to be fearless, resilient, and emotionally stable are in direct conflict with expectations of the treatment programme that one has to demonstrate health-promoting behaviour, such as promptness in attending the care and treatment

  7. Gender differences in diet and nutrition among adults initiating antiretroviral therapy in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Abioye, Ajibola I; Isanaka, Sheila; Liu, Enju; Mwiru, Ramadhani S; Noor, Ramadhani A; Spiegelman, Donna; Mugusi, Ferdinand; Fawzi, Wafaie

    2015-01-01

    Human immunodeficiency virus (HIV)-infected males have poor treatment outcomes after initiation of antiretroviral therapy (ART) compared to HIV-infected women. Dietary factors might mediate the association between sex and disease progression. However, the gender difference in diet among HIV-infected individuals in sub-Saharan Africa is largely unknown. The objective of this study was to examine differences in dietary intake among HIV-infected men and women. We conducted a cross-sectional analysis of dietary questionnaire data from 2038 adults initiating ART in Dar es Salaam, Tanzania to assess whether nutrient adequacy differed by sex. We dichotomized participants' nutrient intakes by whether recommended dietary allowances (RDAs) were met and estimated the relative risk (RR) of meeting RDAs in males using binomial regression models. We also estimated the mean difference in intake of foods and food groups by gender. We found poorer dietary practices among men compared to women. Males were less likely to meet the RDAs for micronutrients critical for slowing disease progression among HIV patients: niacin (RR = 0.39, 95% confidence interval [CI]: 0.27 to 0.55), riboflavin (RR = 0.81, 95% CI: 0.73 to 0.91), vitamin C (RR = 0.94, 95% CI: 0.89 to 1.00), and zinc (RR = 0.06, 95% CI: 0.01 to 0.24). Intake of thiamine, pantothenate, vitamins B6, B12, and E did not vary by gender. Males were less likely to eat cereals (mean difference [servings per day] = -0.21, 95% CI: -0.44 to 0.001) and vegetables (mean difference = -0.47, 95% CI: -0.86 to -0.07) in their diet, but more likely to have meat (mean difference = 0.14, 95% CI: 0.06 to 0.21). We conclude that male HIV patients have poorer dietary practices than females, and this may contribute to faster progression of the disease in males.

  8. Food cravings, aversions and pica among pregnant women in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Nyaruhucha, C N M

    2009-01-01

    Food cravings, aversions and pica are common during pregnancy and may have a significant input on pregnancy progress and outcome. A study was carried out to determine the frequency and duration of pronounced dietary cravings, aversions and pica during pregnancy among 204 pregnant and lactating women attending two health facilities in Dar es Salaam City, Tanzania. Nausea and vomiting were reported by 82.8% of all women of which 43.2% experienced severe nausea alone, 9.5% severe vomiting alone and 35.5% experienced severe vomiting and nausea. Mild cases of each of the symptoms either occurring alone or both of them occurring together were also reported. Both behaviours were observed more in pregnancy. The proportions of women with dietary cravings, aversions, and pica were 73.5%, 70.1% and 63.7% of all women respectively. More women (70.1%) experienced both food cravings and aversions than either symptom alone. Foods craved most were meat (23.3%), mangoes (22.7%), yoghurt (20.0%) oranges (20.0%), plantain (15.3%) and soft drinks (13.3%). Foods avoided most were rice (36.4%), meat (36.4%) and fish (30.8%). Eggs, beans, tea and stiff porridge were also avoided. Reasons given for avoiding foods were unpleasant smell/taste (10.3%), to reduce nausea (11.8%), no particular reason (58.3%) and dislike by foetus (belief) (3.9%). Pica was experienced by 63.7%% of the women and soil, ice and ash were the most commonly non-food substances eaten. The frequency of nausea and vomiting was highest in the early months of pregnancy and most women experienced the symptoms during morning hours. Craving in most women was more intense in the first trimesters. Most women craved for meat and sour and savoury foods, and avoided rice, meat and fish. Soil consumption was the pica observed in most women. Since aversions and cravings are closely linked to dietary intake of pregnant woman understanding these behaviours is important in addressing maternal nutrition.

  9. The spectrum of dermatological disorders among primary school children in Dar es Salaam

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    Mgonda Yassin M

    2010-12-01

    Full Text Available Abstract Background Dermatologic disorders are common in many countries but the spectrum varies greatly. Many studies have reported a significant burden of skin diseases in school children. The objective of this study was to determine the current spectrum of dermatological disorders in primary school children in Dar es Salaam city. Methods Primary school children were recruited by multistage sampling. Detailed interview, dermatological examination and appropriate laboratory investigations were performed. Data was analyzed using the 'Statistical Package for Social Sciences' (SPSS program version 10.0 and EPI6. A p-value of Results A total of 420 children were recruited (51% males; mean age 11.4 ± 2.8 years; range 6-19 years. The overall point prevalence of any skin disorder was 57.3% and it was 61.9% and 52.6% in males and females respectively (p = 0.05. Infectious dermatoses accounted for 30.4% with superficial fungal infections (dermatophytoses and pityriasis versicolor being the commonest (20%. Dermatophytoses were diagnosed in 11.4% (48/420; the prevalence in males and females being 12.6% and 10.1% respectively (p = 0.41 and higher (21.8% in the age-group 6-10 years (p = 0.045. Fungal cultures were positive in 42/48 children (88%. All three dermatophyte genera were isolated. Tinea capitis was the commonest disease among culture-positive dermatophytoses (30/42; 71.4% with an overall prevalence of 7.1% (30/420 followed by tinea pedis (11/42; 26.1% whose overall prevalence was 2.6%. Microsporum canis was common in tinea capitis (14/30; 46.7% followed by Trichophyton violaceum (6/30; 20%. Trichophyton rubrum was common in tinea pedis (5/11; 45.5%. Thirty six children (8.6% had pityriasis versicolor which was more prevalent (6/27; 22.l2% in the age group 16-19 years (p = 0.0004. The other common infectious dermatoses were pyodermas (4% and pediculosis capitis (3.6%. Common non-infectious dermatoses were: acne vulgaris (36.4%, non

  10. Adolescent girls with illegally induced abortion in Dar es Salaam: the discrepancy between sexual behaviour and lack of access to contraception

    DEFF Research Database (Denmark)

    Rasch, V; Silberschmidt, M; Mchumvu, Y;

    2000-01-01

    This article reports on a study of induced abortion among adolescent girls in Dar es Salaam, Tanzania, who were admitted to a district hospital in Dar es Salaam because of an illegally induced abortion in 1997. In the quantitative part of the study, 197 teenage girls (aged 14-19) were asked...... that gave them the right to seek family planning services and in practice these services are not being provided. There is a need for youth-friendly family planning services and to make abortion safe and legal, in order to reduce unwanted pregnancies and abortion-related complications and deaths among...

  11. Exploring the association between women's access to economic resources and intimate partner violence in Dar es Salaam and Mbeya, Tanzania.

    Science.gov (United States)

    Vyas, Seema; Jansen, Henrica Afm; Heise, Lori; Mbwambo, Jessie

    2015-12-01

    The relationship between women's access to economic resources, e.g. employment or access to micro-credit, and experience of intimate partner violence is complex. Empirical evidence documents that in some settings women's employment is associated with higher risk of partner violence but in other settings with lower risk. Evidence also shows that these conflicting associations exist not only between countries but also within different country settings. Using two population-based data sets gathered in 2002 in contrasting Tanzania settings-Dar es Salaam and Mbeya-, we used multivariate logistic regression to examine the relationship between women's access to economic resources and partner violence. Two indicators of economic resources were examined: whether women earned money and whether women owned a business either with someone or exclusively. In Dar es Salaam we found evidence of a higher risk association among women who earned money and who owned a business exclusively by themselves and a lower risk association among women who owned a business with someone. We found no relationship between either indicator of economic resources and partner violence in Mbeya. Other factors were similarly associated with partner violence in both settings and the strongest associations found were related to the respondents' partners: refusal to give money; alcohol use and relationships with other women. The findings support the assertion that women's access to economic resources operate differently in different country settings, thus highlighting the need for targeted prevention efforts that are relevant for the context.

  12. Coping with urban growth and development through environmental planning and management (EPM): the sustainable Dar es Salaam project.

    Science.gov (United States)

    Majani, B B

    1996-03-01

    This article discusses the Urban Management Program (UMP) in Dar es Salaam, Tanzania. The UMP is a joint effort of UNCHS (Habitat), UNDP, and the World Bank. The UMP established the Sustainable Cities Program (SCP) in August 1990. The aim was to provide city officials and their partners in private, public, and popular sectors with improved environmental planning and management capacity. Dar es Salaam has 4 major land formations that constrain management options. About 70% of urban population live in unplanned areas with marginal access to piped water, sanitation, drainage, or basic social services. Improper waste disposal has contributed to water pollution. Under 3% of the city's solid waste is collected. Low lying areas along the coast become flooded, and poor drainage causes continually flooded road systems. SCP began a 4-stage process to identify issues, develop and implement strategy and action plans, and institutionalize the process. An environmental profile was established in 1992. Plans were developed for solid waste management, upgrading unplanned settlements, servicing planned land and city center renewal, and managing open spaces, wastes, and petty trading. These efforts were institutionalized. The efforts are noteworthy for their active participation in plan preparation by key urban managers, multisectoral coordination on environmental issues, involvement of the private sector, establishment of priorities, and detailed action plans. Political support at the highest levels combined with community participation were key to program success. The lessons learned are identified.

  13. A call for parental monitoring to improve condom use among secondary school students in Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Mlunde Linda B

    2012-12-01

    Full Text Available Abstract Background The number of people newly infected with human immunodeficiency virus (HIV has been decreasing in sub-Saharan Africa, but prevalence of the infection remains unacceptably high among young people. Despite the alarming pervasiveness of the virus, young people in this region continue to engage in risky sexual behaviors including unprotected sexual intercourse. In developed countries, parents can play important roles in protecting young people from such behaviors, but evidence regarding the impact of parental involvement is still limited in sub-Saharan Africa. Therefore, we conducted this study to examine the magnitude of risky sexual behaviors and the association of parental monitoring and parental communication with condom use at last sexual intercourse among secondary school students in Dar es Salaam, Tanzania. Methods We conducted this cross-sectional study among 2,217 male and female students aged 15 to 24 years from 12 secondary schools in Dar es Salaam. From October to November 2011, we collected data using a self-administered questionnaire. Multiple logistic regression analyses were conducted to examine the association of parental monitoring and parental communication with condom use at last sexual intercourse, adjusting for potential confounders. Results A total of 665 (30.3% secondary school students reported being sexually active within the year prior to data collection. Among them, 41.7% had multiple sexual partners, 10.5% had concurrent sexual partners, and 41.1% did not use a condom at last sexual intercourse. A higher level of parental monitoring was associated with increased likelihood of condom use at last sexual intercourse among male students (AOR: 1.56, 95% CI: 1.05-2.32; p = 0.03 but not among female students (AOR: 1.54, 95% CI: 0.71-3.37; p = 0.28. The association between parental communication and condom use at last sexual intercourse among both male and female students was not statistically

  14. The problem of illegally induced abortion: results from a hospital-based study conducted at district level in Dar es Salaam

    DEFF Research Database (Denmark)

    Rasch, V; Muhammad, H; Urassa, E;

    2000-01-01

    to describe the circumstances which characterized the abortion. The population of this cross-sectional questionnaire study comprised patients from Temeke District Hospital, Dar es Salaam, Tanzania. After an in-depth confidential interview, 603 women with incomplete abortion were divided into two groups: 362...

  15. Implementation of a goal programming model for solid waste management: a case study of Dar es Salaam – Tanzania

    Directory of Open Access Journals (Sweden)

    Lyeme Halidi Ally

    2017-01-01

    Full Text Available In this research article, the multi-objective optimization model for solid waste management problem is solved by the goal programming method. The model has three objectives: total cost minimization, minimization of final waste disposal to the landfill, and environmental impact minimization. First, the model is solved for the higher priority goal, and then its value is never allowed to deteriorate. The model is solved for the next priority goal and so on until the problem is solved. The model was tested with real data for solid waste management system from Dar es Salaam city. The results determine the best locations for recycling plants, separating plants, composting plants, incinerating plants, landfill and waste flow allocation between them. Furthermore, the solution shows a high reduction of the amount of waste to the landfill and greenhouse gas emissions by 78% and 57.5% respectively if fully implemented compared to the current system.

  16. Adolescent girls, illegal abortions and "sugar-daddies" in Dar es Salaam: vulnerable victims and active social agents

    DEFF Research Database (Denmark)

    Silberschmidt, M; Rasch, V

    2001-01-01

    Adolescent girls' early sexual activity, early pregnancy, induced abortions and the increase in HIV infections have become major concerns in Sub-Saharan Africa. Efforts, though, to understand their sexual behaviour and to prevent reproductive health problems are almost non-existent. Adolescent...... girls are normally seen as victims and easy preys of (often older and married) men's sexual exploitation. This article, which is based on a qualitative study of 51 adolescent girls who had just had an illegal abortion in Dar es Salaam, Tanzania, reveals that these girls are not only victims but also...... willing preys and active social agents engaging in high-risk sexual behaviour. In order to get material benefits they expose themselves to serious health risks, including induced abortion - without realising their own vulnerability. In our study, one out of four girls had more than one partner at the time...

  17. Molecular epidemiology of HIV-associated tuberculosis in Dar es Salaam, Tanzania: strain predominance, clustering, and polyclonal disease.

    Science.gov (United States)

    Adams, Lisa V; Kreiswirth, Barry N; Arbeit, Robert D; Soini, Hanna; Mtei, Lillian; Matee, Mecky; Bakari, Muhammad; Lahey, Timothy; Wieland-Alter, Wendy; Shashkina, Elena; Kurepina, Natalia; Driscoll, Jeffrey R; Pallangyo, Kisali; Horsburgh, C Robert; von Reyn, C Fordham

    2012-08-01

    Molecular typing of Mycobacterium tuberculosis can be used to elucidate the epidemiology of tuberculosis, including the rates of clustering, the frequency of polyclonal disease, and the distribution of genotypic families. We performed IS6110 typing and spoligotyping on M. tuberculosis strains isolated from HIV-infected subjects at baseline or during follow-up in the DarDar Trial in Tanzania and on selected community isolates. Clustering occurred in 203 (74%) of 275 subjects: 124 (80%) of 155 HIV-infected subjects with baseline isolates, 56 (69%) of 81 HIV-infected subjects with endpoint isolates, and 23 (59%) of 39 community controls. Overall, 113 (41%) subjects had an isolate representing the East Indian "GD" family. The rate of clustering was similar among vaccine and placebo recipients and among subjects with or without cellular immune responses to mycobacterial antigens. Polyclonal disease was detected in 6 (43%) of 14 patients with multiple specimens typed. Most cases of HIV-associated tuberculosis among subjects from this study in Dar es Salaam resulted from recently acquired infection. Polyclonal infection was detected and isolates representing the East Indian GD strain family were the most common.

  18. Urban morphological determinants of temperature regulating ecosystem services in African cities: the case of Dar es Salaam, Tanzania

    Science.gov (United States)

    Cavan, Gina; Lindley, Sarah; Kibassa, Deusdedit; Shemdoe, Riziki; Capuano, Paolo; De Paola, Francesco; Renner, Florian; Pauleit, Stephan

    2013-04-01

    Urban green structure provides important regulating ecosystem services, such as temperature and flood regulation, and thus, has the potential to increase the resilience of African cities to climate change. Green structures within urban areas are not only limited to discrete units associated with recreational parks, agricultural areas and open spaces: they also exist within zones which have other primary functions, such as church yards, along transport routes, and within residential areas. Differing characteristics of urban areas can be conceptualised and subsequently mapped through the idea of urban morphology types. Urban morphology types are classifications which combine facets of urban form and function. When mapped, UMT units provide biophysically relevant meso-scale geographical zones which can be used as the basis for understanding climate-related impacts and adaptations. For example, they support the assessment of urban temperature patterns and the temperature regulating services provided by urban green structures. There are some examples of the use of UMTs for assessing regulating ecosystem services in European cities but little similar knowledge is available in an African context. This paper outlines the concept of urban morphology types (UMTs) and how they were applied to African case study cities (Cavan et al., 2012). It then presents the methods used to understand temperature regulating ecosystem services across an example African case study city, including (i) a GIS-based assessment of urban green structures, and (ii) applying an energy balance model to estimate current and future surface temperatures under climate change projections. The assessment is carried out for Dar es Salaam, Tanzania. Existing evidence suggests increases in both mean and extreme temperatures in the city. Historical analysis of the number of hot days per year suggests a rise from a maximum of 47 days per year in the period 1961-87 to 72 days per year in 2003-2011 (Giugni et al

  19. Undernutrition among HIV-positive children in Dar es Salaam, Tanzania: antiretroviral therapy alone is not enough

    Directory of Open Access Journals (Sweden)

    Sunguya Bruno F

    2011-11-01

    Full Text Available Abstract Background The prevalence of HIV/AIDS has exacerbated the impact of childhood undernutrition in many developing countries, including Tanzania. Even with the provision of antiretroviral therapy, undernutrition among HIV-positive children remains a serious problem. Most studies to examine risk factors for undernutrition have been limited to the general population and ART-naive HIV-positive children, making it difficult to generalize findings to ART-treated HIV-positive children. The objectives of this study were thus to compare the proportions of undernutrition among ART-treated HIV-positive and HIV-negative children and to examine factors associated with undernutrition among ART-treated HIV-positive children in Dar es Salaam, Tanzania. Methods From September to October 2010, we conducted a cross-sectional survey among 213 ART-treated HIV-positive and 202 HIV-negative children in Dar es Salaam, Tanzania. We measured the children's anthropometrics, socio-demographic factors, food security, dietary habits, diarrhea episodes, economic status, and HIV clinical stage. Data were analyzed using both univariate and multivariate methods. Results ART-treated HIV-positive children had higher rates of undernutrition than their HIV-negative counterparts. Among the ART-treated HIV-positive children, 78 (36.6% were stunted, 47 (22.1% were underweight, and 29 (13.6% were wasted. Households of ART-treated HIV-positive children exhibited lower economic status, lower levels of education, and higher percentages of unmarried caregivers with higher unemployment rates. Food insecurity was prevalent in over half of ART-treated HIV-positive children's households. Furthermore, ART-treated HIV-positive children were more likely to be orphaned, to be fed less frequently, and to have lower body weight at birth compared to HIV-negative children. In the multivariate analysis, child's HIV-positive status was associated with being underweight (AOR = 4.61, 95% CI 1

  20. Urban schistosomiasis and soil transmitted helminthiases in young school children in Dar es Salaam and Tanga, Tanzania, after a decade of anthelminthic intervention

    DEFF Research Database (Denmark)

    Mwakitalu, Mbutolwe E.; Malecela, Mwele N.; Mosha, Franklin W.;

    2014-01-01

    and control of these infections in urban settings is limited. The present study assessed the status of urinary schistosomiasis and STH across two different-sized cities in Tanzania - Dar es Salaam and Tanga - after a decade of anthelminthic intervention. Primary school children were examined for parasite eggs...... in urine and stool. Questionnaires were administered to the children, and observations were made on the urban environments. The burden of urinary schistosomiasis and STH was found to be low in both cities (overall 1.2% in Dar es Salaam and 0.3% in Tanga for urinary schistosomiasis; overall ... to have been accomplished by implementation of drug based intervention programs, in combination with environmental change (fewer snail habitats) and generally improved levels of hygiene. Continued efforts, including anthelminthic treatment and health education, are important to maintain these positive...

  1. Climate change induced heat wave hazard in eastern Africa: Dar Es Salaam (Tanzania) and Addis Ababa (Ethiopia) case study

    Science.gov (United States)

    Capuano, Paolo; Sellerino, Mariangela; Di Ruocco, Angela; Kombe, Wilbard; Yeshitela, Kumelachew

    2013-04-01

    Last decades, new records were set in the world for tornadoes, drought, wind, floods, wildfires and hot temperatures, testifying unusual weather and climate patterns with increasing frequency and intensity of extreme weather events. Extreme heat events are natural hazards affecting many regions in the world, nevertheless limited work has been done on the analysis and effects of extreme heat events in Africa, that is considered a continent particularly vulnerable to the effects of climate change. In fact, the increase of temperature expected in the African continent during the 21st century is larger than the global mean warming, being about 3° to 4° C, about 1.5 times the global temperature increase (Christensen et al., 2007; Gualdi et al., 2012), with the subtropical regions projected to warm more than the tropical regions. Observations and downscaled model simulations (RCP4.5 and RCP8.5 IPCC scenarios) are analyzed to describe heat wave characteristics in Dar es Salaam (Tanzania) and Addis Ababa (Ethiopia), spanning the last five decades as well as that projected for the 21st century. Observed data are daily maximum and minimum temperature collected in the period 1961-2011; downscaled model simulations span up to 2050. Heat waves are defined following a peak over threshold approach by statistical comparison to historical meteorological baselines (site dependent), using a fixed absolute threshold. Projected future warming in the Dar es Salaam and Addis Ababa shows a further increase in the heat waves parameters. Heat wave duration and hot days number are strictly correlated showing that the temperature rise could generate not only an increase of heat waves number but mainly a longer average duration, that can strongly affect the resilience capacity of the population, particularly the elder people. In fact, the impacts of heat waves on the society are determined also by temporal duration (Stephenson, 2008), in addition to their frequency, in fact the capacity of

  2. Does Personalized Water and Hand Quality Information Affect Attitudes, Behavior, and Health in Dar es Salaam, Tanzania?

    Science.gov (United States)

    Davis, J.; Pickering, A.; Horak, H.; Boehm, A.

    2008-12-01

    Tanzania (TZ) has one of the highest rates of child mortality due to enteric disease in the world. NGOs and local agencies have introduced numerous technologies (e.g., chlorine tablets, borewells) to increase the quantity and quality of water in Dar es Salaam, the capital of Tanzania, in hopes of reducing morbidity and mortality of waterborne disease. The objective of the present study is to determine if providing personalized information about water quality and hand surface quality, as determined by concentrations of enterococci and E. coli, results in improved health and water quality in households. A cohort study was completed in June-September 2008 in 3 communities ranging from urban to per-urban in Dar es Salaam, Tanzania to achieve our objective. The study consisted of 4 cohorts that were visited 4 times over the 3 month study. One cohort received no information about water and hand quality until the end of the summer, while the other groups received either just information on hand surface quality, just information on water quality, and information on both hand surface and water quality after the first (baseline) household visit. We report concentrations of enterococci and E. coli in water sources (surface waters and bore wells), water stored in households, and environmental waters were children and adults swim and bathe. In addition, we report concentrations of enterococci and E. coli on hands of caregivers and children in households. Preliminary results of surveys on health and perceptions of water quality and illness from the households are provided. Ongoing work will integrate the microbiological and sociological data sets to determine if personalized information interventions resulted in changes in health, water quality in the household, or perceptions of water quality, quantity and relation to human health. Future work will analyze DNA samples from hands and water for human-specific Bacteroides bacteria which are only present in human feces. Our study

  3. Age specific aetiological agents of diarrhoea in hospitalized children aged less than five years in Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Myrmel Helge

    2011-02-01

    Full Text Available Abstract Background This study aimed to determine the age-specific aetiologic agents of diarrhoea in children aged less than five years. The study also assessed the efficacy of the empiric treatment of childhood diarrhoea using Integrated Management of Childhood Illness (IMCI guidelines. Methods This study included 280 children aged less than 5 years, admitted with diarrhoea to any of the four major hospitals in Dar es Salaam. Bacterial pathogens were identified using conventional methods. Enzyme Linked Immunosorbent Assay (ELISA and agglutination assay were used to detect viruses and intestinal protozoa, respectively. Antimicrobial susceptibility was determined using Kirby-Bauer disk diffusion method. Results At least one of the searched pathogens was detected in 67.1% of the cases, and mixed infections were detected in 20.7% of cases. Overall, bacteria and viruses contributed equally accounting for 33.2% and 32.2% of all the cases, respectively, while parasites were detected in 19.2% patients. Diarrhoeagenic Escherichia coli (DEC was the most common enteric pathogen, isolated in 22.9% of patients, followed by Cryptosporidium parvum (18.9%, rotavirus (18.1% and norovirus (13.7%. The main cause of diarrhoea in children aged 0 to 6 months were bacteria, predominantly DEC, while viruses predominated in the 7-12 months age group. Vibrio cholerae was isolated mostly in children above two years. Shigella spp, V. cholerae and DEC showed moderate to high rates of resistance to erythromycin, ampicillin, chloramphenicol and tetracycline (56.2-100%. V. cholerae showed full susceptibility to co-trimoxazole (100%, while DEC and Shigella showed high rate of resistance to co-trimoxazole; 90.6% and 93.3% respectively. None of the bacterial pathogens isolated showed resistance to ciprofloxacin which is not recommended for use in children. Cefotaxime resistance was found only in 4.7% of the DEC. Conclusion During the dry season, acute watery diarrhoea is the

  4. Medical evaluation abnormalities in acute psychotic patients seen at the emergency department of Muhimbili national hospital in Dar es Salaam, Tanzania

    OpenAIRE

    S.G. Yusuf*; M.S. Runyon; V. Mwafongo; T.A. Reynolds

    2013-01-01

    Prior studies have shown varied rates of medical pathology in patients presenting to acute care settings with psychotic symptoms, and there is almost no literature from the sub-Saharan Africa region. We investigated the yield of physical examination and laboratory testing among patients presenting with acute psychosis to an urban ED in Dar es Salaam. Methods: This was a prospective observational study of patients presenting to the ED at Muhimbili National Hospital with acute psychosis. A s...

  5. Prevalence of extra-intestinal porcine helminth infections and assessment of sanitary conditions of pig slaughter slabs in Dar es Salaam city, Tanzania.

    Science.gov (United States)

    Mkupasi, Ernatus M; Ngowi, Helena A; Nonga, Hezron Emmanuel

    2011-02-01

    A study was carried out to establish the prevalence of extra-intestinal porcine helminth infections and to assess the pig slaughter slab sanitary conditions in Dar es Salaam city, Tanzania. A total of 24 privately owned pig slaughter slabs were assessed. All slaughter slabs were sub-standard; wrongly located, poorly designed and constructed and lacked most basic requirements for a slaughter house. Because of inadequate slaughtering, disposal and cleaning facilities, the slaughter slabs were under unhygienic condition with questionable safety, soundness and wholesomeness of the pork produced. Routine meat inspection procedures were used to detect extra-intestinal porcine helminth infections. Of the 731 examined pigs; 8.1%, 5.9% and 0.4% were infected with ascariosis, porcine cysticercosis and hydatidosis, respectively. It was noted that almost all slaughter pigs in Dar es Salaam originated from different regions. Based on the region of origin, the status of porcine cysticercosis was 8.2% for Dodoma (n = 98), 8.2% for Manyara (n = 260) and 6.9% for Mbeya (n = 116). This study disclosed the unhygienic sanitary condition prevailing in Dar es Salaam pig slaughter slabs and recommends that strategies should be devised to improve the situation. Porcine ascariosis and cysticercosis were widely prevalent and caused economic losses due to condemnations. Because of their zoonotic nature, the observed extra-intestinal porcine helminth infections in pig pose a public health risk among consumers. Thus, there is a need to introduce appropriate control measures of parasitic infections in pigs.

  6. Application of Vague Analytical Hierarchy Process to Prioritize the Challenges Facing Public Transportation in Dar Es Salaam City-Tanzania

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    Erick P. Massami

    2016-03-01

    Full Text Available Transportation is a key to the economy and social welfare; it makes mobility more accessible and enhances the social and economic interactions. On the other hand, the increase of urban population, pollution and other negative impacts has directly affected the existing transportation system in Dar es Salaam City - Tanzania. As the transportation challenges cannot be overcome simultaneously due to the scarcity of financial resources, a decision support tool is needed to prioritize these challenges. In this study, a composite model of Vague Set Theory (VST and Analytical Hierarchy Process (AHP is applied to appraise the challenges. The Vague Analytical Hierarchy Process (VAHP uses opinions of experts collected from a survey questionnaire. The computational results reveal the ranking in descending order of the urban transportation challenges as poor traffic management, inadequacy of proper public transit service and inadequacy of road transport infrastructure. The results also depict that the VAHP model is a useful decision support tool for transport planners, transport policy makers and other industry stakeholders.

  7. Efficacy of waterless hand hygiene compared with handwashing with soap: a field study in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Pickering, Amy J; Boehm, Alexandria B; Mwanjali, Mathew; Davis, Jennifer

    2010-02-01

    Effective handwashing with soap requires reliable access to water supplies. However, more than three billion persons do not have household-level access to piped water. This research addresses the challenge of improving hand hygiene within water-constrained environments. The antimicrobial efficacy of alcohol-based hand sanitizer, a waterless hand hygiene product, was evaluated and compared with handwashing with soap and water in field conditions in Dar es Salaam, Tanzania. Hand sanitizer use by mothers resulted in 0.66 and 0.64 log reductions per hand of Escherichia coli and fecal streptococci, respectively. In comparison, handwashing with soap resulted in 0.50 and 0.25 log reductions per hand of E. coli and fecal streptococci, respectively. Hand sanitizer was significantly better than handwashing with respect to reduction in levels of fecal streptococci (P = 0.01). The feasibility and health impacts of promoting hand sanitizer as an alternative hand hygiene option for water-constrained environments should be assessed.

  8. Prevalence of obesity and associated risk factors among adults in Kinondoni municipal district, Dar es Salaam Tanzania

    Directory of Open Access Journals (Sweden)

    Mugusi Ferdinand M

    2011-05-01

    Full Text Available Abstract Background Obesity is on the rise worldwide, not sparing developing countries. Both demographic and socio-economic factors play parts in obesity causation. Few surveys have been conducted in Tanzania to determine the magnitude of obesity and its association with these risk factors. This study aimed at determining the prevalence of obesity and its associated risk factors among adults aged 18 - 65 years in Kinondoni municipality, Dar es Salaam, Tanzania from April 2007 to April 2008. Methods Random sampling of households was performed. Interviews and anthropometric measurement were carried out to eligible and consenting members of the selected households. Obesity was defined using Body Mass Index (BMI. Results Out of 1249 subjects recruited, 814 (65.2% were females. The overall prevalence of obesity was 19.2% (240/1249. However, obesity was significantly more prevalent in women (24.7% than men (9%, p Conclusion This study revealed a higher prevalence of obesity among Kinondoni residents than previously reported in other parts of the country. Independent predictors of obesity in the population studied were increasing age, marriage and cohabitation, high SES, female sex and less vigorous physical activities.

  9. Maintenance of Sensitivity of the T-SPOT.TB Assay after Overnight Storage of Blood Samples, Dar es Salaam, Tanzania.

    Science.gov (United States)

    Talbot, Elizabeth A; Maro, Isaac; Ferguson, Katherine; Adams, Lisa V; Mtei, Lillian; Matee, Mecky; von Reyn, C Fordham

    2012-01-01

    Background. T-SPOT.TB is an interferon gamma release assay for detecting Mycobacterium tuberculosis infection. The requirement to process within 8 hours is constraining, deters use, and leads to invalid results. Addition of T Cell Xtend reagent may allow delayed processing, but has not been extensively field tested. Design. Consecutive AFB smear positive adult tuberculosis patients were prospectively recruited in Dar es Salaam, Tanzania. Patients provided a medical history, 1-3 sputum samples for culture and 1 blood sample which was transported to the laboratory under temperature-controlled conditions. After overnight storage, 25 μL of T Cell Xtend reagent was added per mL of blood, and the sample was tested using T-SPOT.TB. Results. 143 patients were enrolled: 57 patients were excluded because temperature control was not maintained, 19 patients were excluded due to red blood cell contamination, and one did not provide a sputum sample for culture. Among 66 evaluable patients, overall agreement between T-SPOT.TB and culture was 95.4% (95%CI; 87.1-99.0%) with Kappa value 0.548. Sensitivity of T-SPOT.TB when using T Cell Xtend reagent was 96.8% (95%CI; 88.8-99.6%). Conclusions. When T Cell Xtend reagent is added to specimens held overnight at recommended temperatures, T-SPOT.TB is as sensitive as the standard assay in patients with tuberculosis.

  10. Public participation and satisfaction in urban regeneration projects in Tanzania: The case of Kariakoo, Dar es Salaam

    Directory of Open Access Journals (Sweden)

    Joseph Paulo Layson

    2015-01-01

    Full Text Available Based on predictions, almost 60% of the world population will be living in cities by 2030. Tanzania is urbanizing at a rapid rate of 4.7%, and 30% of the total population lives in urban areas. Urban regeneration projects in developing countries are facing various challenges. Moreover, the issue of challenges of community participation and satisfaction in regeneration projects is less documented. In recent decades, a bottom-up planning approach has been advocated as an approach for sustainable development planning whereby local actors participate in decision-making. But how top-down planning meets bottom-up planning is less documented, as well as the correlation between participation and satisfaction. This is due to the fact that zoning system has been dominating in urban planning, where experts zone areas according to land uses with an input from the community. In this research community participation, public satisfaction in urban regeneration projects was investigated. The research was based on Kariakoo, Dar es Salaam, Tanzania. The research explored public perceptions on satisfaction and the relationship between community participation and community satisfaction in urban regeneration projects. 292 respondents were interviewed on their perceptions on the redevelopment satisfaction. The results were analyzed using SPSS and tabulated in a form of tables, figures, and charts. The results revealed that it is not necessary that the more the participation the more the satisfaction, hence the more the quality of the service/plan. This means that several factors have an influence on satisfaction of urban redevelopment such as gender, level of education, age, time lived or stayed in the area, as well as the level of participation.

  11. Sampling Migrants from their Social Networks: The Demography and Social Organization of Chinese Migrants in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Merli, M Giovanna; Verdery, Ashton; Mouw, Ted; Li, Jing

    2016-07-01

    The streams of Chinese migration to Africa are growing in tandem with rising Chinese investments and trade flows in and to the African continent. In spite of the high profile of this phenomenon in the media, there are few rich and broad descriptions of Chinese communities in Africa. Reasons for this include the rarity of official statistics on foreign-born populations in African censuses, the absence of predefined sampling frames required to draw representative samples with conventional survey methods and difficulties to reach certain segments of this population. Here, we use a novel network-based approach, Network Sampling with Memory, which overcomes the challenges of sampling 'hidden' populations in the absence of a sampling frame, to recruit a sample of recent Chinese immigrants in Dar es Salaam, Tanzania and collect information on the demographic characteristics, migration histories and social ties of members of this sample. These data reveal a heterogeneous Chinese community composed of "state-led" migrants who come to Africa to work on projects undertaken by large Chinese state-owned enterprises and "independent" migrants who come on their own accord to engage in various types of business ventures. They offer a rich description of the demographic profile and social organization of this community, highlight key differences between the two categories of migrants and map the structure of the social ties linking them. We highlight needs for future research on inter-group differences in individual motivations for migration, economic activities, migration outcomes, expectations about future residence in Africa, social integration and relations with local communities.

  12. Flooding, flood risks and coping strategies in urban informal residential areas: The case of Keko Machungwa, Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Tumpale Sakijege

    2012-06-01

    Full Text Available This article presents findings from a study carried out in Keko Machungwa informal settlement in Dar es Salaam under the auspices of the Disaster Management Training Centre of Ardhi University, Tanzania. The settlement has experienced frequent flooding in the past five years, and this study explores the causes, risks, extent of flooding and coping strategies of residents as well as municipality and city officials. Key methods employed in capturing empirical evidence included mapping of zones by severity of flooding, interviews with households, sub-ward leaders, and municipal and city officials. Non-participant observation, primarily taking photographs, complemented these methods. Laboratory tests of water samples taken from shallow wells in the settlement were performed to establish the level of pollution. In addition, records of prevalence of water-borne diseases were gathered from a dispensary within the settlement to corroborate flooding events, water pollution and occurrence of such diseases. Findings show that flooding is contributed to by the lack of a coordinated stormwater drainage system; haphazard housing development within the valley; and blocking of the water stream by haphazard dumping of solid waste and construction. Risks associated with flooding include water and air pollution, diseases, waterlogging and blocked accessibility. The most common coping strategies at household level are use of sandbags and tree logs; raised pit latrines and doorsteps; provision of water outlet pipes above plinth level; construction of embankments, protection walls and elevation of house foundations; seasonal displacement; and boiling and chemical treatment of water. Recommendations for future action at household, community and city level are made.

  13. Community-based environmental management for malaria control: evidence from a small-scale intervention in Dar es Salaam, Tanzania

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    Kannady Khadija

    2009-04-01

    Full Text Available Abstract Background Historically, environmental management has brought important achievements in malaria control and overall improvements of health conditions. Currently, however, implementation is often considered not to be cost-effective. A community-based environmental management for malaria control was conducted in Dar es Salaam between 2005 and 2007. After community sensitization, two drains were cleaned followed by maintenance. This paper assessed the impact of the intervention on community awareness, prevalence of malaria infection, and Anopheles larval presence in drains. Methods A survey was conducted in neighbourhoods adjacent to cleaned drains; for comparison, neighbourhoods adjacent to two drains treated with larvicides and two drains under no intervention were also surveyed. Data routinely collected by the Urban Malaria Control Programme were also used. Diverse impacts were evaluated through comparison of means, odds ratios (OR, logistic regression, and time trends calculated by moving averages. Results Individual awareness of health risks and intervention goals were significantly higher among sensitized neighbourhoods. A reduction in the odds of malaria infection during the post-cleaning period in intervention neighbourhoods was observed when compared to the pre-cleaning period (OR = 0.12, 95% CI 0.05–0.3, p Anopheles larvae indicated a decline in larval density. In the other drain, lack of proper resources and local commitment limited success. Conclusion Although environmental management was historically coordinated by authoritarian/colonial regimes or by industries/corporations, its successful implementation as part of an integrated vector management framework for malaria control under democratic governments can be possible if four conditions are observed: political will and commitment, community sensitization and participation, provision of financial resources for initial cleaning and structural repairs, and inter

  14. Evaluation of the hygienic quality and associated public health hazards of raw milk marketed by smallholder dairy producers in the Dar es Salaam region, Tanzania.

    Science.gov (United States)

    Kivaria, F M; Noordhuizen, J P T M; Kapaga, A M

    2006-04-01

    A cross-sectional study was conducted to determine three parameters of the quality of the raw milk marketed by milk selling points (MSPs) in Dar es Salaam region. Total bacterial count (TBC) was used as an indicator of the microbial quality of the milk; antimicrobial residues were determined; and the California mastitis test (CMT) was used to screen for milk somatic cells as an indication of the mastitis level in the cows that provided the milk. Moreover, a water sample at each MSP was taken for bacteriological culturing. Finally, a questionnaire survey was conducted with the milk sellers at the MSPs to identify risk factors for poor milk hygiene. A total of 128 milk samples and corresponding water samples were collected from randomly selected milk selling points in Dar es Salaam region. The mean TBC was (8.2 +/- 1.9) x 10(6) cfu/ml, and major bacterial isolates from the milk samples were Escherichia coli (6.3%), Bacillus cereus (6.3%), Staphylococcus aureus (6.3%) and Streptococcus agalactiae (6.3%), Enterobacter aerogenes (5.6%) and Enterococcus faecalis (4.7%). In most cases, the organisms identified in milk corresponded to those isolated from the corresponding water samples. Of milk samples, 79.0% were positive to the CMT and 7.0% were positive for antimicrobial residues. TBC was normalized by log-transformation, and the possible predictors of TBC were identified by fitting two linear regression models. In a random effect model, water microbial quality, frequency of cleaning the milk containers, frequency of milk supply, milk storage time and the type of containers, and mixing of fresh and previous milk were significantly (p milk sold in Dar es Salaam region is of poor quality and is of public health significance.

  15. Determinants of immunological failure among clients on the first line treatment with highly active antiretroviral drugs in Dar es Salaam, Tanzania

    Institute of Scientific and Technical Information of China (English)

    Anthony Kapesa; Daniel Magesa; Alexander William; John Kaswija; Jeremiah Seni; Cyprian Makwaya

    2014-01-01

    Objective:To determine socio-cultural, demographic and highly active antiretroviral therapy (HAART) program-related factors associated with immunological failure (IF) among clients on HAART in Dar es Salaam care and treatment clinics. Methods:A 1:2 matched case control study was done from February to April 2012 in HIV/AIDS care and treatment clinics in Dar es Salaam. Data were collected from National AIDS Control Program (NACP) data base and patient’s charts to obtain 60 sets of study participants who were interviewed using the structured questionnaire. Data analysis was done by using EPI Info 3.5.1 version. Results:The mean age of all study participants was (42.00±9.07) years with 35% (63) being males. History of poor antiretroviral therapy (ART) adherence due to exposure to drug holiday with loss to follow up (OR=11.96;95%CI=2.07-69.26), history of changing care and treatment clinics (OR=12.07;95%CI=2.10-69.27) and the lack of treatment supporter (OR=23.26;95%CI=1.85-291.66) were found to be strongly associated with the occurrence of first line HAART-IF. Conclusions:HAART-IF in Dar es Salaam is associated with ART programmatic and patients’ centered challenges. There is a need to review the approaches on ensuring ART adherence, clients follow up and referral system so as to reduce the incidence of IF as we move to a more decentralized peripheral drug picks clinical initiative.

  16. The magnitude and factors associated with delays in management of smear positive tuberculosis in Dar es Salaam, Tanzania

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    Ngadaya Esther

    2008-07-01

    Full Text Available Abstract Objective To assess the magnitude and factors responsible for delay in TB management. Design A cross sectional hospital based survey in Dar es Salaam region, May 2006. Results We interviewed 639 TB patients. A total of 78.4% of patients had good knowledge on TB transmission. Only 35.9% had good knowledge on the symptoms. Patient delay was observed in 35.1% of the patients, with significantly (X2 = 5.49, d.f. = 1, P = 0.019 high proportion in females (41.0% than in males (31.5%. Diagnosis delay was observed in 52.9% of the patients, with significantly (X2 = 10.1, d.f. = 1, P = 0.001 high proportion in females (62.1% than in males (47.0%. Treatment delay was observed in 34.4% of patients with no significant differences among males and females. Several risk factors were significantly associated with patient's delays in females but not in males. The factors included not recognizing the following as TB symptoms: night sweat (OR = 1.92, 95% CI 1.20, 3.05, chest pain (OR = 1.62, 95% CI 1.1, 2.37, weight loss (OR = 1.55, 95% CI 1.03, 2.32, and coughing blood (OR = 1.47, 95% CI 1.01, 2.16. Other factors included: living more than 5 Km from a health facility (OR = 2.24, 95% CI 1.41, 3.55, no primary education (OR = 1.74, 95% CI 1.01, 3.05 and no employment (OR = 1.77, 95% CI 1.20, 2.60. In multiple logistic regression, five factors were more significant in females (OR = 2.22, 95% CI 1.14, 4.31 than in males (OR = 0.70, 95% CI 0.44, 1.11. These factors included not knowing that night sweat and chest pain are TB symptoms, a belief that TB is always associated with HIV infection, no employment and living far from a health facility. Conclusion There were significant delays in the management of TB patients which were contributed by both patients and health facilities. However, delays in most of patients were due to delay of diagnosis and treatment in health facilities. The delays at all levels were more common in females than males. This indicates the

  17. Roadside concentration of gaseous and particulate matter pollutants and risk assessment in Dar-es-Salaam, Tanzania.

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    Jackson, Msafiri M

    2005-05-01

    This study used manual air sampling method to assess the contribution of road traffic to air pollution level in Dar-es-Salaam City, Tanzania. Samples were collected from 11 different sites. Parameters measured were: sulphur dioxide using pararosaniline method, nitrogen dioxide using saltzman method, particulate matter and particulate lead using filtration method and atomic absorption spectrometric method, respectively. Results showed that hourly average sulphur dioxide concentration range from 127 to 1385 microg/m3. The measured values of sulphur dioxide were above the recommended WHO guidelines with an hourly objective value of 350 microg/m3 at 87% of the sampling sites. The hourly average nitrogen dioxide concentration ranged from 18 to 53 microg/m3. The maximum hourly nitrogen dioxide concentration at 53 microg/m3 was below the WHO guideline value of 200 microg/m3. The hourly average suspended particulate matter (SPM) ranged from 98 to 1161 microg/m3, exceeding the recommended value of 230 microg/m3 by WHO at 87% of the sampling sites. The hourly average lead concentration was found to range from 0.60 to 25.6 microg/m3, exceeding again the WHO guideline value of 1.5 microg/m3 at 83% of the sampling sites. Results predicted by Gaussian model when compared with the measured values were found to have a correlation coefficient of 0.8, signifying a good correlation. The risk assessment was undertaken considering the people who spend a significant portion of their time near the roads, such as the Uhuru primary school pupils and the adult population who reside by the roadside. The unit risk realised was 18.2 x 10(-6) for adult population and 2.2 x 10(-6) for pupils, both scenarios showing risk higher than the United Sates of America Environmental Protection Agency (USEPA) acceptable limit of 1 x 10(-6). Considering the magnitude of the problem at hand, this study recommends an introduction of mandatory emission tests of SPM, lead and sulphur dioxide (SO2). The study

  18. Microalbuminuria among Type 1 and Type 2 diabetic patients of African origin in Dar Es Salaam, Tanzania

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    Thordarson Hrafnkell

    2007-01-01

    Full Text Available Abstract Background The prevalences and risk factors of microalbuminuria are not full described among black African diabetic patients. This study aimed at determining the prevalence of microalbuminuria among African diabetes patients in Dar es Salaam, Tanzania, and relate to socio-demographic features as well as clinical parameters. Methods Cross sectional study on 91 Type 1 and 153 Type 2 diabetic patients. Two overnight urine samples per patient were analysed. Albumin concentration was measured by an automated immunoturbidity assay. Average albumin excretion rate (AER was used and were categorised as normalbuminuria (AER 200 ug/min. Information obtained also included age, diabetes duration, sex, body mass index, blood pressure, serum total cholesterol, high-density and low-density lipoprotein cholesterol, triglycerides, serum creatinine, and glycated hemoglobin A1c. Results Overall prevalence of microalbuminuria was 10.7% and macroalbuminuria 4.9%. In Type 1 patients microalbuminuria was 12% and macroalbuminuria 1%. Among Type 2 patients, 9.8% had microalbuminuria, and 7.2% had macroalbuminuria. Type 2 patients with abnormal albumin excretion rate had significantly longer diabetes duration 7.5 (0.2–24 yrs than those with normal albumin excretion rate 3 (0–25 yrs, p No significant differences in body mass index, glycaemic control, and cholesterol levels was found among patients with normal compared with those with elevated albumin excretion rate either in Type 1 or Type 2 patients. A stepwise multiple linear regression analysis among Type 2 patients, revealed AER (natural log AER as the dependent variable to be predicted by [odds ratio (95% confidence interval] diabetes duration 0.090 (0.049, 0.131, p Conclusion The prevalence of micro and macroalbuminuria is higher among African Type 1 patients with relatively short diabetes duration compared with prevalences among Caucasians. In Type 2 patients, the prevalence is in accordance with

  19. Monitoring mosquitoes in urban Dar es Salaam: Evaluation of resting boxes, window exit traps, CDC light traps, Ifakara tent traps and human landing catches

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    Mpangile John M

    2011-03-01

    Full Text Available Abstract Background Ifakara tent traps (ITT are currently the only sufficiently sensitive, safe, affordable and practical method for routine monitoring host-seeking mosquito densities in Dar es Salaam. However, it is not clear whether ITT catches represent indoors or outdoors biting densities. ITT do not yield samples of resting, fed mosquitoes for blood meal analysis. Methods Outdoors mosquito sampling methods, namely human landing catch (HLC, ITT (Design B and resting boxes (RB were conducted in parallel with indoors sampling using HLC, Centers for Disease Control and Prevention miniature light traps (LT and RB as well as window exit traps (WET in urban Dar es Salaam, rotating them thirteen times through a 3 × 3 Latin Square experimental design replicated in four blocks of three houses. This study was conducted between 6th May and 2rd July 2008, during the main rainy season when mosquito biting densities reach their annual peak. Results The mean sensitivities of indoor RB, outdoor RB, WET, LT, ITT (Design B and HLC placed outdoor relative to HLC placed indoor were 0.01, 0.005, 0.036, 0.052, 0.374, and 1.294 for Anopheles gambiae sensu lato (96% An. gambiae s.s and 4% An. arabiensis, respectively, and 0.017, 0.053, 0.125, 0.423, 0.372 and 1.140 for Culex spp, respectively. The ITT (Design B catches correlated slightly better to indoor HLC (r2 = 0.619, P 2 = 0.231, P = 0.001 than outdoor HLC (r2 = 0.423, P 2 = 0.228, P = 0.001 for An. gambiae s.l. and Culex spp respectively but the taxonomic composition of mosquitoes caught by ITT does not match those of the indoor HLC (χ2 = 607.408, degrees of freedom = 18, P An. gambiae caught indoors was unaffected by the use of an LLIN in that house. Conclusion The RB, WET and LT are poor methods for surveillance of malaria vector densities in urban Dar es Salaam compared to ITT and HLC but there is still uncertainty over whether the ITT best reflects indoor or outdoor biting densities. The particular LLIN

  20. Physical, Sexual, Emotional and Economic Intimate Partner Violence and Controlling Behaviors during Pregnancy and Postpartum among Women in Dar es Salaam, Tanzania

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    Mahenge, Bathsheba; Stöckl, Heidi; Abubakari, Abdulai; Mbwambo, Jessie; Jahn, Albrecht

    2016-01-01

    Background Intimate partner violence (IPV) during pregnancy and postpartum is a serious global health problem affecting millions of women worldwide. This study sought to determine the prevalence of different forms of IPV during pregnancy and postpartum and associated factors among women in Dar es Salaam, Tanzania. Methods We conducted a cross-sectional study among 500 women at one to nine months postpartum in three health facilities in the three districts of Dar es Salaam: Temeke, Kinondoni and Illala. Two trained research assistants administered the questionnaire, which aimed to examine sociodemographic characteristics and different forms of IPV. Results Of the 500 women who were interviewed, 18.8% experienced some physical and/or sexual violence during pregnancy. Forty-one women (9%) reported having experienced some physical and/or sexual violence at one to nine months postpartum. Physical and/or sexual IPV during pregnancy was associated with cohabiting (AOR 2.2, 95% CI 1.24–4.03) and having a partner who was 25 years old or younger (AOR 2.7, 95% CI 1.08–6.71). Postpartum, physical and/or sexual IPV was associated with having a partner who was 25 years old or younger (AOR 4.4, 95% CI 1.24–15.6). Conclusion We found that IPV is more prevalent during pregnancy than during the postpartum phase. There is also continuity and maintenance of IPV during and after pregnancy. These results call for policy and interventions to be tailored for pregnant and postpartum women. PMID:27755559

  1. Participatory mapping of target areas to enable operational larval source management to suppress malaria vector mosquitoes in Dar es Salaam, Tanzania

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    Dongus Stefan

    2007-09-01

    Full Text Available Abstract Background Half of the population of Africa will soon live in towns and cities where it can be protected from malaria by controlling aquatic stages of mosquitoes. Rigorous but affordable and scaleable methods for mapping and managing mosquito habitats are required to enable effective larval control in urban Africa. Methods A simple community-based mapping procedure that requires no electronic devices in the field was developed to facilitate routine larval surveillance in Dar es Salaam, Tanzania. The mapping procedure included (1 community-based development of sketch maps and (2 verification of sketch maps through technical teams using laminated aerial photographs in the field which were later digitized and analysed using Geographical Information Systems (GIS. Results Three urban wards of Dar es Salaam were comprehensively mapped, covering an area of 16.8 km2. Over thirty percent of this area were not included in preliminary community-based sketch mapping, mostly because they were areas that do not appear on local government residential lists. The use of aerial photographs and basic GIS allowed rapid identification and inclusion of these key areas, as well as more equal distribution of the workload of malaria control field staff. Conclusion The procedure developed enables complete coverage of targeted areas with larval control through comprehensive spatial coverage with community-derived sketch maps. The procedure is practical, affordable, and requires minimal technical skills. This approach can be readily integrated into malaria vector control programmes, scaled up to towns and cities all over Tanzania and adapted to urban settings elsewhere in Africa.

  2. Examining the potential for modal change : motivators and barriers for bicycle commuting in Dar-es-Salaam

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    Nkurunziza, A.; Zuidgeest, M.H.P.; Brussel, M.J.G.; Maarseveen, van M.F.A.M.

    2012-01-01

    The paper examines the effect of various motivators, barriers and policy related interventions (i.e., personal, social and physical–environmental factors) on bicycle commuting in Dares-Salaam, Tanzania. The research shows that these factors have different effects on people depending on the stage of

  3. Organic liquids storage tanks volatile organic compounds (VOCS) emissions dispersion and risk assessment in developing countries: the case of Dar-es-Salaam City, Tanzania.

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    Jackson, Msafiri M

    2006-05-01

    The emission estimation of nine volatile organic compounds (VOCs) from eight organic liquids storage tanks companies in Dar-es-Salaam City Tanzania has been done by using US EPA standard regulatory storage tanks emission model (TANKS 4.9b). Total VOCs atmospheric emission has been established to be 853.20 metric tones/yr. It has been established further that petrol storage tanks contribute about 87% of total VOCs emitted, while tanks for other refined products and crude oil were emitting 10% and 3% of VOCs respectively. Of the eight sources (companies), the highest emission value from a single source was 233,222.94 kg/yr and the lowest single source emission value was 6881.87 kg/yr. The total VOCs emissions estimated for each of the eight sources were found to be higher than the standard level of 40,000 kg/yr per source for minor source according to US EPA except for two sources, which were emitting VOCs below the standard level. The annual emissions per single source for each of the VOCs were found to be below the US EPA emissions standard which is 2,000 kg/yr in all companies except the emission of hexane from company F1 which was slightly higher than the standard. The type of tanks used seems to significantly influence the emission rate. Vertical fixed roof tanks (VFRT) emit a lot more than externally floating roof tanks (EFRT) and internally floating roof tanks (IFRT). The use of IFRT and EFRT should be encouraged especially for storage of petrol which had highest atmospheric emission contribution. Model predicted atmospheric emissions are less than annual losses measured by companies in all the eight sources. It is possible that there are other routes for losses beside atmospheric emissions. It is therefore important that waste reduction efforts in these companies are directed not only to reducing atmospheric emissions, but also prevention of the spillage and leakage of stored liquid and curbing of the frequently reported illegal siphoning of stored products

  4. A Mismatch between High-Risk Behaviors and Screening of Infectious Diseases among People Who Inject Drugs in Dar es Salaam, Tanzania.

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    Linda Beatrice Mlunde

    Full Text Available People who inject drugs are at risk of various infectious diseases. Despite such a risk, evidence is limited which studied the utilization of screening services for common infectious diseases among people who inject drugs in Tanzania. We aimed to examine their high-risk behaviors; utilization of screening services for HIV infection, hepatitis B/C, any other sexually transmitted infection, and tuberculosis; and their associated factors in Dar es Salaam, Tanzania.We conducted a baseline cross-sectional study as part of a prospective cohort study of people who inject drugs. We included 578 participants comprising of new enrollees of the integrated methadone-assisted treatment program and those who were selected from the communities but not enrolled in the program. We interviewed new enrollees preceding their enrollment and receipt of services from the program. We measured participants' high-risk behaviors and their utilization of screening services. We analyzed the data descriptively and used multiple logistic regressions to identify the factors associated with ever being screened for infectious diseases.Of 578 participants, 14.2% shared injection needles. Of 547 sexually active participants, 37.5% had multiple sexual partners and only 17.4% used a condom. Of all participants, however, only 36.0% had ever been screened for HIV infection, 18.5% for tuberculosis, 11.8% for any other sexually transmitted infection, and 11.6% for hepatitis B/C. They were more likely to have ever been screened for HIV infection if they had education levels above primary education (adjusted odds ratio [AOR]: 2.54, 95% CI: 1.54-4.20, had a history of transactional sex (OR: 2.63, 95% CI: 1.01-6.84, and were new enrollees of the program (AOR: 7.41, 95% CI: 4.41-12.86.People who inject drugs practice high-risk behaviors but their utilization of screening services for infectious diseases is poor in Dar es Salaam, Tanzania. It is crucial to increase the coverage of screening

  5. Ready to Use Therapeutic Foods (RUTF improves undernutrition among ART-treated, HIV-positive children in Dar es Salaam, Tanzania

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    Sunguya Bruno F

    2012-08-01

    Full Text Available Abstract Background HIV/AIDS is associated with an increased burden of undernutrition among children even under antiretroviral therapy (ART. To treat undernutrition, WHO endorsed the use of Ready to Use Therapeutic Foods (RUTF that can reduce case fatality and undernutrition among ART-naïve HIV-positive children. However, its effects are not studied among ART-treated, HIV-positive children. Therefore, we examined the association between RUTF use with underweight, wasting, and stunting statuses among ART-treated HIV-positive children in Dar es Salaam, Tanzania. Methods This cross-sectional study was conducted from September-October 2010. The target population was 219 ART-treated, HIV-positive children and the same number of their caregivers. We used questionnaires to measure socio-economic factors, food security, RUTF-use, and ART-duration. Our outcome variables were underweight, wasting, and stunting statuses. Results Of 219 ART-treated, HIV-positive children, 140 (63.9% had received RUTF intervention prior to the interview. The percentages of underweight and wasting among non-RUTF-receivers were 12.4% and 16.5%; whereas those of RUTF-receivers were 3.0% (P = 0.006 and 2.8% (P = 0.001, respectively. RUTF-receivers were less likely to have underweight (Adjusted Odd Ratio (AOR =0.19, CI: 0.04, 0.78, and wasting (AOR = 0.24, CI: 0.07, 0.81, compared to non RUTF-receivers. Among RUTF receivers, children treated for at least four months (n = 84 were less likely to have underweight (P = 0.049, wasting (P = 0.049 and stunting (P  Conclusions Among HIV-positive children under ART, the provision of RUTF for at least four months was associated with low proportions of undernutrition status. RUTF has a potential to improve undernutrition among HIV-positive children under ART in the clinical settings in Dar es Salaam, Tanzania.

  6. Improved quality of management of eclampsia patients through criteria based audit at Muhimbili National Hospital, Dar es Salaam, Tanzania. Bridging the quality gap

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    Kidanto Hussein

    2012-11-01

    Full Text Available Abstract Background Criteria-based audits (CBA have been used to improve clinical management in developed countries, but have only recently been introduced in the developing world. This study discusses the use of a CBA to improve quality of care among eclampsia patients admitted at a University teaching hospital in Dar es Salaam Tanzania. Objective The prevalence of eclampsia in MNH is high (≈6% with the majority of cases arriving after start of convulsions. In 2004–2005 the case-fatality rate in eclampsia was 5.1% of all pregnant women admitted for delivery (MNH obstetric data base. A criteria-based audit (CBA was used to evaluate the quality of care for eclamptic mothers admitted at Muhimbili National Hospital (MNH, Dar es Salaam, Tanzania after implementation of recommendations of a previous audit. Methods A CBA of eclampsia cases was conducted at MNH. Management practices were evaluated using evidence-based criteria for appropriate care. The Ministry of Health (MOH guidelines, local management guidelines, the WHO manual supplemented by the WHO Reproductive Health Library, standard textbooks, the Cochrane database and reviews in peer reviewed journals were adopted. At the initial audit in 2006, 389 case notes were assessed and compared with the standards, gaps were identified, recommendations made followed by implementation. A re-audit of 88 cases was conducted in 2009 and compared with the initial audit. Results There was significant improvement in quality of patient management and outcome between the initial and re-audit: Review of management plan by senior staff (76% vs. 99%; P=0.001, urine for albumin test (61% vs. 99%; P=0.001, proper use of partogram to monitor labour (75% vs. 95%; P=0.003, treatment with steroids for lung maturity (2.0% vs. 24%; P=0.001, Caesarean section within 2 hours of decision (33% vs. 61%; P=0.005, full blood count (28% vs. 93%; P=0.001, serum urea and creatinine (44% vs. 86%; P=0.001, liver enzymes (4.0% vs

  7. The contribution of ineffective urban planning practices to disaster and disaster risks accumulation in urban areas: the case of former Kunduchi quarry site in Dar es Salaam, Tanzania

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    Benedict F. Malele

    2009-04-01

    Full Text Available This study examined the link between urban planning practices and disaster risks. The study used the former Kunduchi Quarry Site within the City of Dar es Salaam to demonstrate how laxity in enforcing the laid down planning rules, regulations and procedures facilitates the accumulation and occurrence of disaster risks and disasters in urban areas. This undermines one of the central roles of urban planning, which is to protect the lives of people from disaster risks and disasters. In exploring this, the study specifically focused on understanding the rules, regulations and procedures of planning in Tanzania; the extent to which they are followed and, where they are not followed, their implications for disaster risks and disasters; the coping initiatives adopted by local communities to reduce risks and their level of success or failure; and finally the drawing of lessons and recommendations for disaster risk reduction in urban areas. Strongly emerging from this study is the finding that although planning rules and regulations do exist, they are not enforced. As a result urban communities suffer from disaster risks and disasters caused by unregulated activities. The study analyzed the coping initiatives that urban communities apply to reduce disaster risks in their areas. It noted that, while a range of “coping” responses could be observed, these are not lasting solutions to the disaster risks being faced. Sustainable solutions seem to be known by the local community but they are not adopted for fear of compromising or undermining their existing livelihood strategies.

  8. Role of traditional healers in psychosocial support in caring for the orphans: A case of Dar-es Salaam City, Tanzania

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    Massila Mariam

    2005-07-01

    Full Text Available Abstract Orphans are an increasing problem in developing countries particularly in Africa; due to the HIV/AIDS pandemic; and needs collective effort in intervention processes by including all stakeholders right from the grass roots level. This paper attempts to present the role of traditional healers in psychosocial support for orphan children in Dar-es-Salaam City with special focus on those whose parents have died because of HIV/AIDS. Six traditional healers who were involved in taking care of orphans were visited at their "vilinge" (traditional clinics. In total they had 72 orphans, 31 being boys and 41 being girls with age range from 3 years to 19. It was learned that traditional healers, besides providing remedies for illnesses/diseases of orphans, they also provided other basic needs. Further, they even provided psychosocial support allowing children to cope with orphan hood life with ease. Traditional healers are living within communities at the grass roots level; and appear unnoticed hidden forces, which are involved in taking care of orphans. This role of traditional healers in taking care of orphans needs to be recognised and even scaling it up by empowering them both in financial terms and training in basic skills of psychosocial techniques in how to handle orphans, in order to reduce discrimination and stigmatisation in the communities where they live.

  9. Leveraging strong social ties among young men in Dar es Salaam: A pilot intervention of microfinance and peer leadership for HIV and gender-based violence prevention.

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    Maman, Suzanne; Kajula, Lusajo; Balvanz, Peter; Kilonzo, Mrema; Mulawa, Marta; Yamanis, Thespina

    2016-12-01

    Gender inequality is at the core of the HIV patterns that are evident in sub-Saharan Africa. Gender-based violence (GBV) and lack of economic opportunity are important structural determinants of HIV risk. We piloted a microfinance and health promotion intervention among social networks of primarily young men in Dar es Salaam. Twenty-two individuals participated in the microfinance component and 30 peer leaders were recruited and trained in the peer health leadership component. We collected and analysed observational data from trainings, monitoring data on loan repayment, and reports of peer conversations to assess the feasibility and acceptability of the intervention. Eighteen of the loan recipients (82%) paid back their loans, and of these 15 (83%) received a second, larger loan. Among the loan defaulters, one died, one had chronic health problems, and two disappeared, one of whom was imprisoned for theft. The majority of conversations reported by peer health leaders focused on condoms, sexual partner selection, and HIV testing. Few peer leaders reported conversations about GBV. We demonstrated the feasibility and acceptability of this innovative HIV and GBV prevention intervention. The lessons learned from this pilot have informed the implementation of a cluster-randomised trial of the microfinance and peer health leadership intervention.

  10. Assessment of physicochemical characteristics and hygienic practices along the value chain of raw fruit juice vended in Dar es Salaam City, Tanzania.

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    Nonga, Hezron E; Simforian, Edeltruds A; Ndabikunze, Bernadette K

    2014-10-01

    Fresh fruit juice is an essential component of human diet and there is considerable evidence of health and nutritional benefits. However, nature of the fruits used in juicing and unhygienic processes in the value chain may cause poor quality of juice. This cross- sectional study was conducted to assess physicochemical characteristics and hygienic practices along the value chain of raw fruit juice vended in Dar es Salaam, Tanzania. A total of 90 juice vendors were interviewed. Ninety juice samples were collected and analysed for physicochemical quality. The pH of juices ranged between 2.7 and 6.4, acidity 0.01% and 1.3% and, total soluble solids ranged between -1.5 and 18.04 °Brix. Most juices (67.8%) had -Brix levels below Codex recommended values classified as weak and watery. Juices were made of mango, passion, tamarind, sugar cane and mixture of these fruits sourced from open markets in the city. Water for washing of fruits and dilution of juices was from deep wells (53.3%) and taps (46.7%). About one third (37.8%) of the juice vendors didn't wash the fruits before juicing and 44.4% didn't boil water for juice dilution. Juice extraction was done by kitchen blenders, boiling in water and squeezing by simple machines. Juice pasteurization was not done. The majority of vendors (78.9%) stored juices in plastic buckets and juice was sold in glass cups, reused plastic bottles and disposable cups. Vending sites were restaurants, bus stands and along roadsides. The majority of premises (78.9%) were in unhygienic condition that likely encouraged or introduced contaminants to the juices. It is concluded that, the overall handling, preparation practices and physicochemical quality of raw fruit juices vended in Dare es Salaam City are poor. The government should educate the vendors on food safety and hygiene as well as enforcing regular monitoring of the quality of street fruit juices.

  11. Determination of Levels of Organochlorine, Organophosphorus, and Pyrethroid Pesticide Residues in Vegetables from Markets in Dar es Salaam by GC-MS

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    John A. M. Mahugija

    2017-01-01

    Full Text Available This study investigated the levels of pesticides and metabolites in vegetables from major markets in Dar es Salaam city, Tanzania. Samples of fresh cabbage, spinach, and onions from the markets were analysed for pesticide residues. Extraction was performed using acetone followed by dichloromethane : cyclohexane mixture and the extracts were cleaned up using Florisil. The compounds were determined by gas chromatography-mass spectrometry (GC-MS. Pesticides and metabolites were detected in 72.2% of the samples. The detected pesticide residues and their highest mean concentrations were p,p′-DDT 4.00 × 10−3 mg/kg, p,p′-DDD 6.40 × 10−1 mg/kg, o,p′-DDD 1.00 × 10−2 mg/kg, α-endosulfan 6.00 × 10−1 mg/kg, β-endosulfan 2.10 × 10−1 mg/kg, chlorpyrifos 3.00 mg/kg, and cypermethrin 4.00 × 10−2 mg/kg. The most frequently detected compounds were p,p′-DDD and chlorpyrifos. The order of contamination was spinach > cabbage > onions. Generally, there were no significant variations in concentrations of pesticide residues among samples and sampling sites, which indicated similarities in contamination patterns. The concentrations of contaminants were above the maximum residue limits (MRLs in 33.3–50% of the samples. The findings indicated risks and concerns for public health.

  12. Putting the genie back in the bottle? Availability and presentation of oral artemisinin compounds at retail pharmacies in urban Dar-es-Salaam

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    Black Carolyn

    2006-03-01

    Full Text Available Abstract Background Recently global health advocates have called for the introduction of artemisinin-containing antimalarial combination therapies to help curb the impact of drug-resistant malaria in Africa. Retail trade in artemisinin monotherapies could undermine efforts to restrict this class of medicines to more theoretically sound combination treatments. Methods This paper describes a systematic search for artemisinin-containing products at a random sample of licensed pharmacies in Dar-es-Salaam, Tanzania in July 2005. Results Nineteen different artemisinin-containing oral pharmaceutical products, including one co-formulated product, one co-packaged product, and 17 monotherapies were identified. All but one of the products were legally registered and samples of each product were obtained without a prescription. Packaging and labeling of the products seldom included local language or illustrated instructions for low-literate clients. Packaging and inserts compared reasonably well with standards recommended by the national regulatory authority with some important exceptions. Dosing instructions were inconsistent, and most recommended inadequate doses based on international standards. None of the monotherapy products mentioned potential benefits of combining the treatment with another antimalarial drug. Conclusion The findings confirm the widespread availability of artemisinin monotherapies that led the World Health Organization to call for the voluntary withdrawal of these drugs in malaria-endemic countries. As the global public health community gathers resources to deploy artemisinin-containing combination therapies in Africa, planners should be mindful that these drugs will coexist with artemisinin monotherapies in an already well-established market place. In particular, regulatory authorities should be incorporated urgently into the process of planning for rational deployment of artemisinin-containing antimalarial combination therapies.

  13. Cervical pre-malignant lesions in HIV infected women attending Care and Treatment Centre in a tertiary hospital, Dar es Salaam, Tanzania.

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    Balandya, Belinda S; Pembe, Andrea B; Mwakyoma, Henry A

    2011-09-01

    The aims of this study was to determine proportion of HIV infected women with cervical pre-malignant lesions; and compare the use of Visual Inspection of the cervix after application of Acetic acid (VIA) and Papanicolau (Pap) smear in screening for cervical premalignant lesions in HIV positive women attending Care and Treatment Centre (CTC) at Muhimbili National Hospital (MNH), Dar es Salaam, Tanzania. A total of 316 women aged 18-70 years had a Pap smear taken for cytology, followed by spraying onto the cervix with 4% acetic acid and then inspecting it. Cytology was considered negative when there was no Cervical Intraepithelial Neoplasia (CIN) lesion reported from the Pap smear taken, and positive if CIN lesion 1, 2 or 3 was reported. Detection of a well-defined, opaque acetowhite lesion close to the squamocolumnar junction or close to the external cervical os constituted a positive VIA. Out of 316 women, 132 women had acetowhite lesions on VIA, making the proportion of abnormal cervical lesions to be 42.4%. One hundred and one out of 312 women (32.4%) had CIN lesions detected on Pap smear. The proportion of agreement between these two tests was 0.3. The proportion of agreement was moderate in women with advanced WHO HIV clinical stage of the disease and in women not on ART (Anti Retroviral Therapy). Women with CD-4 count less than 200 cells/mm3 had more abnormal cervical lesions. There is considerable proportion of HIV positive women with premalignant lesions of the cervix. Considering the proportion of HIV women with abnormal lesions and the difficulty in logistics of doing Pap smear in low resource settings, these results supports the recommendation to introduce screening of premalignant lesions of the cervix using VIA to all HIV infected women.

  14. Balancing collective responsibility, individual opportunities and risks: a qualitative study on how police officers reason around volunteering in an HIV vaccine trial in Dar es Salaam, Tanzania

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    Bakari Muhammad

    2010-05-01

    Full Text Available Abstract Background Results from HIV vaccine trials on potential volunteers will contribute to global efforts to develop an HIV vaccine. The purpose of this study among police officers in Dar es Salaam, Tanzania, was to explore the underlying reasons that induce people to enrol in an HIV vaccine trial. Methods We conducted discussions with eight focus groups, containing a total of 66 police officers. The information collected was analyzed using interpretive description. Results The results showed that participants were motivated to participate in the trial by altruism, and that the participants experienced some concerns about their participation. They stated that altruism in the fight against HIV infection was the main reason for enrolling in the trial. However, young participants were seriously concerned about a possible loss of close relationships if they enrolled in the HIV vaccine trial. Both men and women feared the effect of the trial on their reproductive biology, and they feared interference with pregnancy norms. They were unsure about risks such as the risks of acquiring HIV infection and of suffering physical harm, and they were unsure of the intentions of the researchers conducting the trial. Further, enrolling in the trial required medical examination, and this led some participants to fear that unknown diseases would be revealed. Other participants, however, saw an opportunity to obtain free health services. Conclusions We have shown that specific fears are important concerns when recruiting volunteers to an HIV vaccine trial. More knowledge is needed to determine participants' views and to ensure that they understand the conduct of the trial and the reasons it is being carried out.

  15. Prevalence of Hypertension and Its Associated Risk Factors among 34,111 HAART Naïve HIV-Infected Adults in Dar es Salaam, Tanzania

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    Marina Njelekela

    2016-01-01

    Full Text Available Background. Elevated blood pressure has been reported among treatment naïve HIV-infected patients. We investigated prevalence of hypertension and its associated risk factors in a HAART naïve HIV-infected population in Dar es Salaam, Tanzania. Methods. A cross-sectional analysis was conducted among HAART naïve HIV-infected patients. Hypertension was defined as systolic blood pressure (SBP ≥ 140 mmHg and/or diastolic blood pressure (DBP ≥ 90 mmHg. Overweight and obesity were defined as body mass index (BMI between 25.0–29.9 kg/m2 and ≥30 kg/m2, respectively. We used relative risks to examine factors associated with hypertension. Results. Prevalence of hypertension was found to be 12.5%. After adjusting for possible confounders, risk of hypertension was 10% more in male than female patients. Patients aged ≥50 years had more than 2-fold increased risk for hypertension compared to 30–39-years-old patients. Overweight and obesity were associated with 51% and 94% increased risk for hypertension compared to normal weight patients. Low CD4+ T-cell count, advanced WHO clinical disease stage, and history of TB were associated with 10%, 42%, and 14% decreased risk for hypertension. Conclusions. Older age, male gender, and overweight/obesity were associated with hypertension. Immune suppression and history of TB were associated with lower risk for hypertension. HIV treatment programs should screen and manage hypertension even in HAART naïve individuals.

  16. Maternal and neonatal colonisation of group B streptococcus at Muhimbili National Hospital in Dar es Salaam, Tanzania: prevalence, risk factors and antimicrobial resistance

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    Lyamuya Eligius F

    2009-12-01

    Full Text Available Abstract Background Group B streptococcus (GBS, which asymptomatically colonises the vaginal and rectal areas of women, is the leading cause of septicemia, meningitis and pneumonia in neonates. In Tanzania no studies have been done on GBS colonisation of pregnant women and neonates. This study was conducted in Dar es Salaam, Tanzania to determine the prevalence of GBS colonisation among pregnant women, the neonatal colonisation rate and the antimicrobial susceptibility, thus providing essential information to formulate a policy for treatment and prevention regarding perinatal GBS diseases. Methods This cross sectional study involved 300 pregnant women attending antenatal clinic and their newborns delivered at Muhimbili National Hospital (MNH between October 2008 and March 2009. High vaginal, rectal, nasal, ear and umbilical swabs were cultured on Todd Hewitt Broth and in 5% sheep blood agar followed by identification of isolates using conventional methods and testing for their susceptibility to antimicrobial agents using the Kirby-Bauer method. Results GBS colonisation was confirmed in 23% of pregnant women and 8.9% of neonates. A higher proportion of GBS were isolated from the vagina (12.3% as compared to the rectum (5%. Prolonged duration of labour (>12 hrs was significantly shown to influence GBS colonisation in neonates P Conclusion Our findings seem to suggest that a quarter of pregnant women attending ANC clinic at MNH and approximately 10% of their newborns are colonised with GBS. All isolates were found to be sensitive to vancomycin and ampicillin which seem to be the most effective antibiotics for the time being. However there is a need for continuous antibiotics surveillance of GBS to monitor trend of resistance. The high isolation frequency of GBS among pregnant women suggests routine antenatal screening at 35 to 37 weeks of gestation in order to provide antibiotic prophylaxis to GBS carrier.

  17. Mosquito control in Dar es Salaam. II. Impact of expanded polystyrene beads and pyriproxyfen treatment of breeding sites on Culex quinquefasciatus densities.

    Science.gov (United States)

    Chavasse, D C; Lines, J D; Ichimori, K; Majala, A R; Minjas, J N; Marijani, J

    1995-04-01

    In two contrasting areas of Dar es Salaam (Ilala and Mikocheni) all enclosed breeding sites of Culex quinquefasciatus, such as latrines and septic tanks, were treated with a floating layer of expanded polystyrene beads. 7 months later checks in both study areas revealed only one site (from which the polystyrene had been removed during emptying) containing immature stages of Cx quinquefasciatus. Open breeding sites such as areas of flooded land and blocked drains were treated with pyriproxyfen (an insect growth regulator) at a concentration of 0.1 ppm. Emergence of Cx quinquefasciatus adults from these sites was inhibited for 4 weeks during the rainy season and for up to 11 weeks during the dry season. The problem of mosquito breeding sites caused by bathroom sullage water was addressed through a combination of health education and indirect pressure from the Urban Malaria Control Project (UMCP) via local community leaders. Households responsible for these sites were encouraged to eliminate them by diverting the water into an enclosed drainage structure, usually a pit latrine. After two weekly visits 64.7% of households had complied and 93.4% had complied after five visits. 5 months later, only 15.7% had reverted to allowing sullage water to collect into puddles. Densities of Cx quinquefasciatus adults dropped by 76.7% in Mikocheni and by 46.2% in Ilala following intervention, but increased by 84.9% and 25.6% in two untreated comparison areas. The reasons for differential success of the combined interventions in the two treated areas are discussed.

  18. Reduction of anti-malarial consumption after rapid diagnostic tests implementation in Dar es Salaam: a before-after and cluster randomized controlled study

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    Swai Ndeniria

    2011-04-01

    Full Text Available Abstract Background Presumptive treatment of all febrile patients with anti-malarials leads to massive over-treatment. The aim was to assess the effect of implementing malaria rapid diagnostic tests (mRDTs on prescription of anti-malarials in urban Tanzania. Methods The design was a prospective collection of routine statistics from ledger books and cross-sectional surveys before and after intervention in randomly selected health facilities (HF in Dar es Salaam, Tanzania. The participants were all clinicians and their patients in the above health facilities. The intervention consisted of training and introduction of mRDTs in all three hospitals and in six HF. Three HF without mRDTs were selected as matched controls. The use of routine mRDT and treatment upon result was advised for all patients complaining of fever, including children under five years of age. The main outcome measures were: (1 anti-malarial consumption recorded from routine statistics in ledger books of all HF before and after intervention; (2 anti-malarial prescription recorded during observed consultations in cross-sectional surveys conducted in all HF before and 18 months after mRDT implementation. Results Based on routine statistics, the amount of artemether-lumefantrine blisters used post-intervention was reduced by 68% (95%CI 57-80 in intervention and 32% (9-54 in control HF. For quinine vials, the reduction was 63% (54-72 in intervention and an increase of 2.49 times (1.62-3.35 in control HF. Before-and-after cross-sectional surveys showed a similar decrease from 75% to 20% in the proportion of patients receiving anti-malarial treatment (Risk ratio 0.23, 95%CI 0.20-0.26. The cluster randomized analysis showed a considerable difference of anti-malarial prescription between intervention HF (22% and control HF (60% (Risk ratio 0.30, 95%CI 0.14-0.70. Adherence to test result was excellent since only 7% of negative patients received an anti-malarial. However, antibiotic

  19. Effects of seasonal change and seawater intrusion on water quality for drinking and irrigation purposes, in coastal aquifers of Dar es Salaam, Tanzania

    Science.gov (United States)

    Sappa, Giuseppe; Ergul, Sibel; Ferranti, Flavia; Sweya, Lukuba Ngalya; Luciani, Giulia

    2015-05-01

    Groundwater is the major source to meet domestic, industrial and agricultural needs in the city of Dar es Salaam, Tanzania. However, population growth, increasing urbanization, industrialization and tourism, and climatic changes have caused an intensive exploitation of groundwater resources leading the aquifers become more vulnerable to seawater intrusion. The aim of this study is to examine the variations of groundwater chemistry (as resulting from natural and anthropogenic inputs) depending on seasonal changes, in order to evaluate water quality for drinking and irrigation purposes. Physical and chemical data come from the analysis of groundwater samples, collected from 72 wells, used for the evaluation of water quality parameters, during a year of monitoring. Pattern diagrams, geochemical modeling techniques and Principal Component Analysis (PCA) have been used to identify the main factors influencing groundwater composition. Based on the hydrochemistry, the groundwater was classified into three types: (a) Na-Cl, (b) Ca-Cl, (c) mixed Ca-Na-HCO3-Cl (d) mixed Ca-Mg-Cl-SO4. The geochemical modeling results show that groundwater chemistry is mainly influenced by evaporation process, as it is suggested by the increase of Na and Cl ions concentrations. According to irrigation water quality assessment diagrams of USDA, most water samples from dry and rainy seasons, distributed in category C2-S1, C3-S1, C3-S2, C4-S2 highlighting medium to very high salinity hazard and low to medium sodium content class. PCA evidenced the role of seawater intrusion, evaporation process and anthropogenic pollution (i.e. high NO3 levels due to agricultural activities), as the major factors that influenced the water chemistry, and hence the water quality. Based on Pearson correlation matrix, the presence of high correlations (>0.8) among Na, Cl, Mg and SO4, in association with EC, were interpreted as the seawater intrusion effects. In this area groundwater quality is generally low, and

  20. Informal support to first-parents after childbirth: a qualitative study in low-income suburbs of Dar es Salaam, Tanzania

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    Mbekenga Columba K

    2011-11-01

    Full Text Available Abstract Background In Tanzania, and many sub-Saharan African countries, postpartum health programs have received less attention compared to other maternity care programs and therefore new parents rely on informal support. Knowledge on how informal support is understood by its stakeholders to be able to improve the health in families after childbirth is required. This study aimed to explore discourses on health related informal support to first-time parents after childbirth in low-income suburbs of Dar es Salaam, Tanzania. Methods Thirteen focus group discussions with first-time parents and female and male informal supporters were analysed by discourse analysis. Results The dominant discourse was that after childbirth a first time mother needed and should be provided with support for care of the infant, herself and the household work by the maternal or paternal mother or other close and extended family members. In their absence, neighbours and friends were described as reconstructing informal support. Informal support was provided conditionally, where poor socio-economic status and non-adherence to social norms risked poor support. Support to new fathers was constructed as less prominent, provided mainly by older men and focused on economy and sexual matters. The discourse conveyed stereotypic gender roles with women described as family caretakers and men as final decision-makers and financial providers. The informal supporters regulated the first-time parents' contacts with other sources of support. Conclusions Strong and authoritative informal support networks appear to persist. However, poverty and non-adherence to social norms was understood as resulting in less support. Family health in this context would be improved by capitalising on existing informal support networks while discouraging norms promoting harmful practices and attending to the poorest. Upholding stereotypic notions of femininity and masculinity implies great burden of care

  1. Effect of Improved access to Antiretroviral Therapy on clinical characteristics of patients enrolled in the HIV care and treatment clinic, at Muhimbili National Hospital (MNH, Dar es Salaam, Tanzania

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    Swai Andrew B

    2010-05-01

    Full Text Available Abstract Background Sub-Saharan Africa has been severely affected by the HIV and AIDS pandemic. Global efforts at improving care and treatment has included scaling up use of antiretroviral therapy (ART. In Tanzania, HIV care and treatment program, including the provision of free ART started in 2004 with a pilot program at Muhimbili National Hospital in Dar es Salaam. This study describes the socio-demographic and clinical features of patients enrolled at the care and treatment clinic at MNH, Dar es Salaam, Tanzania. Methods A cross-sectional study looking at baseline characteristics of patients enrolled at the HIV clinic at MNH between June 2004 - Dec 2005 compared to those enrolled between 2006 and September 2008. Results Of all enrolled patients, 2408 (58.5% were used for analysis. More females than males were attending the clinic. Their baseline median CD4 cell count was low (136 cells/μl with 65.7% having below 200 cells/μl. Females had higher CD4 cell counts (150 cells/μl than males (109 cells/μl p Conclusion Patients enrolled to the MNH HIV clinic were predominantly females, and presented with advanced immune-deficiency. Improved access to HIV care and treatment services seems to be associated with patients' early presentation to the clinics in the course of HIV disease.

  2. Seroprevalence of hepatitis B and C viral co-infections among children infected with human immunodeficiency virus attending the paediatric HIV care and treatment center at Muhimbili National Hospital in Dar-es-Salaam, Tanzania

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    Munubhi Emmanuel K

    2007-11-01

    Full Text Available Abstract Background With increased availability of antibiotics and antifungal agents hepatitis B virus (HBV and hepatitis C virus (HCV infections are becoming a cause for significant concern in HIV infected children. We determined the seroprevalence and risk factors for HBV and HCV among HIV infected children aged 18 months to 17 years, attending the Paediatric HIV Care and Treatment Center (CTC at Muhimbili National Hospital (MNH in Dar-es-Salaam, Tanzania. Methods Investigations included; interviews, physical examination and serology for HBsAg, IgG antibodies to HCV and alanine aminotransferase (ALT levels. HIV serostatus and CD4 counts were obtained from patient records. Results 167 HIV infected children, 88(52.7% males and 79(47.3% females were enrolled. The overall prevalence of hepatitis co-infection was 15%, with the seroprevalence of HBV and HCV being 1.2% and 13.8%, respectively. Hepatitis virus co-infection was not associated with any of the investigated risk factors and there was no association between HBV and HCV. Elevated ALT was associated with hepatitis viral co-infection but not with ART usage or immune status. Conclusion The high seroprevalence (15% of hepatitis co-infection in HIV infected children attending the Paediatrics HIV CTC at the MNH calls for routine screening of hepatitis viral co-infection and modification in the management of HIV infected children.

  3. Sanitary inspection of wells using risk-of-contamination scoring indicates a high predictive ability for bacterial faecal pollution in the peri-urban tropical lowlands of Dar es Salaam, Tanzania.

    Science.gov (United States)

    Mushi, Douglas; Byamukama, Denis; Kirschner, Alexander K T; Mach, Robert L; Brunner, K; Farnleitner, Andreas H

    2012-06-01

    Sanitary inspection of wells was performed according to World Health Organization (WHO) procedures using risk-of-contamination (ROC) scoring in the peri-urban tropical lowlands of Dar es Salaam, Tanzania. The ROC was assessed for its capacity to predict bacterial faecal pollution in the investigated well water. The analysis was based on a selection of wells representing environments with low to high presumptive faecal pollution risk and a multi-parametric data set of bacterial indicators, generating a comprehensive picture of the level and characteristics of faecal pollution (such as vegetative Escherichia coli cells, Clostridium perfringens spores and human-associated sorbitol fermenting Bifidobacteria). ROC scoring demonstrated a remarkable ability to predict bacterial faecal pollution levels in the investigated well water (e.g. 87% of E. coli concentration variations were predicted by ROC scoring). Physicochemical characteristics of the wells were not reflected by the ROC scores. Our results indicate that ROC scoring is a useful tool for supporting health-related well water management in urban and suburban areas of tropical, developing countries. The outcome of this study is discussed in the context of previously published results, and future directions are suggested.

  4. Infant and young child feeding practices among children under 2 years of age and maternal exposure to infant and young child feeding messages and promotions in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Vitta, Bineti S; Benjamin, Margaret; Pries, Alissa M; Champeny, Mary; Zehner, Elizabeth; Huffman, Sandra L

    2016-04-01

    There are limited data describing infant and young child feeding practices (IYCF) in urban Tanzania. This study assessed the types of foods consumed by children under 2 years of age and maternal exposure to promotions of these foods in Dar es Salaam, Tanzania. A cross-sectional survey was conducted among 305 mothers of children less than 24 months of age who attended child health services in October and November, 2014. Among infants less than 6 months of age, rates of exclusive breastfeeding were low (40.8%) and a high proportion (38.2%) received semi-solid foods. Continued breastfeeding among 20-23-month-olds was only 33.3%. Consumption of breastmilk substitutes was not prevalent, and only 3.9% of infants less than 6 months of age and 4.8% of 6-23 month-olds were fed formula. Among 6-23-month-olds, only 38.4% consumed a minimum acceptable diet (using a modified definition). The homemade complementary foods consumed by the majority of 6-23-month-olds (85.2%) were cereal-dominated and infrequently contained micronutrient-rich ingredients. Only 3.1% of 6-23-month-olds consumed commercially produced infant cereal on the day preceding the interview. In contrast, commercially produced snack foods were consumed by 23.1% of 6-23-month-olds. Maternal exposure to commercial promotions of breastmilk substitutes and commercially produced complementary foods was low (10.5% and 1.0%, respectively), while exposure to promotions of commercially produced snack foods was high (45.9%). Strategies are needed to improve IYCF practices, particularly with regard to exclusive and continued breastfeeding, increased dietary diversity and consumption of micronutrient-rich foods, and avoidance of feeding commercially produced snack foods.

  5. The perceptions on male circumcision as a preventive measure against HIV infection and considerations in scaling up of the services: a qualitative study among police officers in Dar es Salaam, Tanzania

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    Tarimo Edith AM

    2012-07-01

    Full Text Available Abstract Background In recent randomized controlled trials, male circumcision has been proven to complement the available biomedical interventions in decreasing HIV transmission from infected women to uninfected men. Consequently, Tanzania is striving to scale-up safe medical male circumcision to reduce HIV transmission. However, there is a need to investigate the perceptions of male circumcision in Tanzania using specific populations. The purpose of the present study was to assess the perceptions of male circumcision in a cohort of police officers that also served as a source of volunteers for a phase I/II HIV vaccine (HIVIS-03 trial in Dar es Salaam, Tanzania. Methods In-depth interviews with 24 men and 10 women were conducted. Content analysis informed by the socio-ecological model was used to analyze the data. Results Informants perceived male circumcision as a health-promoting practice that may prevent HIV transmission and other sexually transmitted infections. They reported male circumcision promotes sexual pleasure, confidence and hygiene or sexual cleanliness. They added that it is a religious ritual and a cultural practice that enhances the recognition of manhood in the community. However, informants were concerned about the cost involved in male circumcision and cleanliness of instruments used in medical and traditional male circumcision. They also expressed confusion about the shame of undergoing circumcision at an advanced age and pain that could emanate after circumcision. The participants advocated for health policies that promote medical male circumcision at childhood, specifically along with the vaccination program. Conclusions The perceived benefit of male circumcision as a preventive strategy to HIV and other sexually transmitted infections is important. However, there is a need to ensure that male circumcision is conducted under hygienic conditions. Integrating male circumcision service in the routine childhood vaccination

  6. Developing Fashion/Textile Design Education in Dar es Salaam

    OpenAIRE

    2008-01-01

    Interviews conducted during May 2007 and at a subsequent workshop on 16th January 2008 confirm that employment opportunities in textile design tend to be limited to the small scale entrepreneurs taking on trainees or staff or to become self employed. \\ud \\ud Self-employment appears to be the most immediate form of business operation in the fashion/textile design business. The local entrepreneurs interviewed in the study were involved in design through manufacture to retail. To help the entrep...

  7. Koulujen sanitaatiotilanne Tansaniassa : Dar es Salaamin ja Moshin alueilla

    OpenAIRE

    Partanen, Lotta

    2013-01-01

    Tutkimuksen tavoitteena oli tehdä selvitys Tansanian koulujen sanitaatiotilanteesta sekä miettiä mahdollisia ratkaisuja sanitaatio-olojen parantamiseksi. Lisäksi tavoitteena oli tutkia kuivakäymälän toimivuutta paikallisissa olosuhteissa sekä pohtia, voisiko menetelmä toimia ratkaisuna koulujen sanitaatio-ongelmiin. Työ suoritettiin syksyllä 2012 Tansaniassa Dar es Salaamin ja Moshin kaupungeissa. Noin 47 miljoonan asukkaan Tansania sijaitsee Itä-Afrikassa Intian valtameren rannalla. Se o...

  8. Child trafficking in Tanzania: Experiences of Trafficked Girls in Dar es Salaam

    OpenAIRE

    Kavishe, Angela

    2011-01-01

    This study focuses on the experiences of trafficked children in Tanzania. Trafficking of children deprives them of human rights and freedoms; it may also pose a public health risk. Migration of children who are fostered by extended family is a long-standing customary practice in Tanzania, but while the circumstances of fostering have changed, given increasing rural poverty and the impact of the HIV/AIDS, this has not been recognized in Tanzanian society. The government enacted the Anti-Traffi...

  9. Comparing spatial patterns of informal settlements between Nairobi and Dar es Salaam

    OpenAIRE

    Sirueri, Felix

    2015-01-01

    Currently, in many cities in the developing world, spatial data on informal settlements are generalized, outdated, or even non-existent. Moreover, there is a lack of comprehensive information about spatial factors that influence the location of informal settlements a cross different cities. These settlements continue to develop posing many urban challenges. This research employs locational and morphological parameters to measure and quantify the patterns of informal settlements using two exam...

  10. Challenging HIV vulnerability discourse: the case of professional and entrepreneurial women in Dar Es Salaam, Tanzania.

    Science.gov (United States)

    Jangu, Neema William; Tam, Ailie; Maticka-Tyndale, Eleanor

    2016-11-11

    A poverty-HIV narrative has dominated many HIV prevention strategies in Africa despite epidemiological data showing higher prevalence of infection among educated and wealthier women in several African countries. This paper examines the perspectives of professional and entrepreneurial women on HIV risk and vulnerability based on their knowledge and lived experiences, comparing this to the HIV discourse evident in five strategic documents that shape intervention in Tanzania. The purpose is to uncover the confluence and dissonance between the discourses of government and those of professional women themselves. Qualitative research methods included critical discourse analysis of five strategic documents and thematic analysis of 37 in-depth interviews with women. The findings challenge fixed representations of women and notions of vulnerability embedded in the poverty-HIV discourse. Women described using their sexuality and sexual agency as a means to elevate their position in ways that made them vulnerable to sexual harassment and coercion. This is explored through two intersecting themes: non-marital sexual exchanges to gain an education or employment, and marriage. The intersecting social positions and constructions of female sexuality and agency expressed by the women in this study provide insights into other avenues and forms of HIV vulnerability.

  11. Antimicrobial activity of medicated soaps commonly used by Dar es Salaam residents in Tanzania

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    K D Mwambete

    2011-01-01

    Full Text Available An in vitro evaluation of the anti-microbial activity of medicated soaps was conducted using ditch-plate and hand washing techniques. Strains of reference microbes namely Candida albicans (ATCC90028, Staphylococcus aureus (ATCC25923, Pseudomonas aureginosa (ATCC27853 and Escherichia coli (ATCC25922 were tested at three different soaps′ concentrations (1.0, 4.0 and 8.0 mg/ml. A total of 16 medicated soaps were assayed for their antimicrobial efficacy. Of these, 13 were medicated and 3 non-medicated soaps, which served as control. Ciprofloxacin and ketaconazole were employed as positive controls. Label disclosure for the soaps′ ingredients and other relevant information were absorbed. The most common antimicrobial active ingredients were triclosan, trichloroxylenol and trichlorocarbanilide. ANOVA for means of zones of inhibition revealed variability of antimicrobial activity among the medicated soaps. Positive correlation (r=0.318; P<0.01 between zones of inhibition and soaps′ concentrations was evidenced. Hand washing frequencies positively correlated with microbial counts. Roberts® soap exhibited the largest zone of inhibition (34 mm on S. aureus. Candida albicans was the least susceptible microbe. Regency® and Dalan® exhibited the least zone of inhibition on the tested bacteria. Protex® , Roberts® , Family® and Protector® were equally effective (P<0.01 against S. aureus. In conclusion, majority of the assayed medicated soaps have satisfactory antibacterial activity; though lack antifungal effect with exception of Linda® liquid soap. The hand washing technique has proved to be inappropriate for evaluation of soaps′ antimicrobial efficacy due to presence of the skin microflora.

  12. Sexual history and contraception among women with induced and spontaneous abortion in Dar es Salaam

    DEFF Research Database (Denmark)

    Rasch, V; Mary, V; Urassa, E;

    2007-01-01

    The objective of this study was to create sexual history profiles of women with illegally induced abortion (IA) and women with spontaneous abortion (SA) and describe the women's knowledge of, attitude to, and practice of contraception. The study was carried out in two settings, Temeke District...... the rate of ever users of contraception was low in both groups, although significantly lower among IA women than among SA women. Outcome of first pregnancy had been an induced abortion in significantly higher proportion of IA than of SA women. In conclusion, sexual intercourse before marriage is common...

  13. Risk factors for VIA positivity and determinants of screening attendances in Dar es Salaam, Tanzania

    DEFF Research Database (Denmark)

    Kahesa, Crispin; Kjaer, Susanne Kruger; Ngoma, Twalib;

    2012-01-01

    ABSTRACT: BACKGROUND: Tanzania is among the countries in the world where the cervical cancer incidence is estimated to be highest. Acknowledging an increase in the burden of cervical cancer, VIA was implemented as a regional cervical cancer screening strategy in Tanzania in 2002. With the aim of ...

  14. Introduction of a qualitative perinatal audit at Muhimbili National Hospital, Dar es Salaam, Tanzania

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    Thomas Angela N

    2009-09-01

    Full Text Available Abstract Background Perinatal death is a devastating experience for the mother and of concern in clinical practice. Regular perinatal audit may identify suboptimal care related to perinatal deaths and thus appropriate measures for its reduction. The aim of this study was to perform a qualitative perinatal audit of intrapartum and early neonatal deaths and propose means of reducing the perinatal mortality rate (PMR. Methods From 1st August, 2007 to 31st December, 2007 we conducted an audit of perinatal deaths (n = 133 with birth weight 1500 g or more at Muhimbili National Hospital (MNH. The audit was done by three obstetricians, two external and one internal auditors. Each auditor independently evaluated the cases narratives. Suboptimal factors were identified in the antepartum, intrapartum and early neonatal period and classified into three levels of delay (community, infrastructure and health care. The contribution of each suboptimal factor to adverse perinatal outcome was identified and the case graded according to possible avoidability. Degree of agreement between auditors was assessed by the kappa coefficient. Results The PMR was 92 per 1000 total births. Suboptimal factors were identified in 80% of audited cases and half of suboptimal factors were found to be the likely cause of adverse perinatal outcome and were preventable. Poor foetal heart monitoring during labour was indirectly associated with over 40% of perinatal death. There was a poor to fair agreement between external and internal auditors. Conclusion There are significant areas of care that need improvement. Poor monitoring during labour was a major cause of avoidable perinatal mortality. This type of audit was a good starting point for quality assurance at MNH. Regular perinatal audits to identify avoidable causes of perinatal deaths with feed back to the staff may be a useful strategy to reduce perinatal mortality.

  15. Acceptance of contraceptives among women who had an unsafe abortion in Dar es Salaam

    DEFF Research Database (Denmark)

    Rasch, Vibeke; Massawe, Siriel; Yambesi, Fortunata

    2004-01-01

    or an induced abortion performed at the hospital (n=788) were counselled about contraception and the risk of contracting STDs/HIV. A free ward-based contraceptive service was offered and the women were asked to return for follow-up. RESULTS: Participants (90%) accepted the post-abortion contraceptive service....... Of these, 86% stated they were still using contraception 1-6 months after discharge. Initially, 55% of the women accepted to use condoms either alone or as part of double protection. After 1-6 months this proportion had dropped to 18%. Single women were significantly more likely to use condoms. CONCLUSION...

  16. Exploring Sustainable Urban Food Provisioning: The Case of Eggs in Dar es Salaam

    NARCIS (Netherlands)

    Wegerif, M.C.A.

    2014-01-01

    Global food supply is dominated by transnational corporations, which have great power and are widely critiqued for the negative environmental and social impacts of their operations. Many argue that this industrial food system is unsustainable, yet its expansion seems inevitable and alternatives are

  17. Parenting practices and styles associated with adolescent sexual health in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Kajula, Lusajo J; Darling, Nancy; Kaaya, Sylvia F; De Vries, Hein

    2016-11-01

    Parenting styles and practices are suggested to be important predictors of adolescent sexual health, mostly in Europe and North America. Limited research has been conducted on these processes in Sub-Saharan Africa, which has different patterns of adolescent sexual behavior and family traditions. This study qualitatively explored parenting practices and styles associated with adolescent sexual health in Tanzania, with 12 adolescents and 12 parents of adolescents. The themes we identified from the data included parental monitoring, preventive, and punitive behaviors. Parents were reported to use mostly punitive behaviors to correct or prohibit sexual behavior; parents also set clear rules about appropriate sexual behavior (e.g., modesty and abstinence). Parents were also reported to closely monitor their adolescent children's friendships and sexual behavior to minimize sexual behavior. However, some parents also engaged in positive preventive practices aimed at protecting their adolescent children.

  18. Managing Informal Settlements : A Study Using Geo-Information in Dar es Salaam, Tanzania

    NARCIS (Netherlands)

    Šliužas, Ričardas Vytautas

    2004-01-01

    Urbanization in Sub-Saharan Africa (SSA) is often associated with the urbanization of poverty, and with the extensive development of informal settlements. This thesis examines how Geographic Information Technology (GIT) could be used to improve the ability of local governments in SSA manage such set

  19. Ecology and Epidemiology of Integrated Malaria Vector Management in Dar es Salaam, Tanzania

    OpenAIRE

    Geissbühler, Yvonne

    2008-01-01

    Malaria remains one of the major contributors to the global burden of disease with approximately 70% of the clinical malaria attacks occurring in sub-Saharan Africa. Sub- Saharan Africa has the highest risk as ideal climatic conditions for transmission coincide with occurrence of some of the most efficient malaria vectors, namely Anopheles gambiae s.s., Anopheles arabiensis and Anopheles funestus.. Even though it is estimated that by the year 2030 more than 50% of the African p...

  20. Risk and Protective Factors for Relapse among Individuals with Schizophrenia: A Qualitative Study in Dar es Salaam, Tanzania.

    OpenAIRE

    Sariah, Adellah E; Outwater, Anne H; Malima, Khadija I Y

    2014-01-01

    Background Relapse in people with schizophrenia is a major challenge for mental health service providers in Tanzania and other countries. Approximately 10% of people with schizophrenia are re-admitted due to relapse at Muhimbili National Hospital (MNH) Psychiatric Unit each month. Relapse brings about negative effects and it results in a huge burden to patients, their families, the mental health sector and the country’s economy. So far no study has been done to address relapse in Tanzania. Th...

  1. Social venues that protect against and promote HIV risk for young men in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Yamanis, Thespina J; Maman, Suzanne; Mbwambo, Jessie K; Earp, Jo Anne E; Kajula, Lusajo J

    2010-11-01

    Developing effective place-based health interventions requires understanding of the dynamic between place and health. The therapeutic landscape framework explains how place-based social processes and physical geography interact and influence health behavior. This study applied this framework to examine how venues, or social gathering places, influenced HIV risk behavior among young, urban men in Tanzania. Eighty-three public venues where men aged 15-19 met new sexual partners were identified by community informants in one city ward. The majority (86%) of the venues were called 'camps', social gathering places that had formal leaders and members. Observations were conducted at 23 camps and in-depth interviews were conducted with 36 camp members and 10 camp leaders in 15 purposively selected camps. Geographic and social features of camps were examined to understand their contributions to men's behaviors. Camps were characterized by a geographic space claimed by members, a unique name and a democratic system of leadership and governance. Members were mostly men and socialized daily at their camp. They reported strong social bonds and engaging in health-promoting activities such as playing sports and generating income. Members also engaged in HIV risk behaviors, such as meeting new sexual partners and having sex in or around the camp at night. Some members promoted concurrent sexual partnerships with their friends and resisted camp leaders' efforts to change their sexual risk behavior. We conclude that camps are strategic venues for HIV prevention programs for young Tanzanian men. They served as both protective and risk landscapes, illustrating three domains of the therapeutic landscape framework: the built environment; identities of landscape occupants; and sites for collective efficacy. The framework and data suggest HIV intervention components might augment the protective features of the camps, while changing environmental features to reduce risk.

  2. Assessment of knowledge and skills of triage amongst nurses working in the emergency centres in Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Robert Aloyce

    2014-03-01

    Discussion: Nurses who participated in this study demonstrated significant deficits in knowledge and skills regarding patients’ triaging in the EC. To correct these deficits, immediate in-service training/education workshops should be carried out, followed by continuous professional development on a regular basis, including refresher training, supportive supervision and clinical skills sessions.

  3. Community response to artemisinin-based combination therapy for childhood malaria: a case study from Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Nyato Daniel J

    2010-02-01

    Full Text Available Abstract Background New malaria treatment guidelines in Tanzania have led to the large-scale deployment of artemether-lumefantrine (Coartem®, popularly known as ALu or dawa mseto. Very little is known about how people in malaria endemic areas interpret policy makers' decision to replace existing anti-malarials, such as sulphadoxine-pyrimethamine (SP with "new" treatment regimens, such as ALu or other formulations of ACT. This study was conducted to examine community level understandings and interpretations of ALu's efficacy and side-effects. The paper specifically examines the perceived efficacy of ALu as articulated by the mothers of young children diagnosed with malaria and prescribed ALu. Methods Participant observation, six focus group discussions in two large villages, followed by interviews with a random sample of 110 mothers of children less than five years of age, who were diagnosed with malaria and prescribed ALu. Additionally, observations were conducted in two village dispensaries involving interactions between mothers/caretakers and health care providers. Results While more than two-thirds of the mothers had an overall negative disposition toward SP, 97.5% of them spoke favourably about ALu, emphasizing it's ability to help their children to rapidly recover from malaria, without undesirable side-effects. 62.5% of the mothers reported that they were spending less money dealing with malaria than previously when their child was treated with SP. 88% of the mothers had waited for 48 hours or more after the onset of fever before taking their child to the dispensary. Mothers' knowledge and reporting of ALu's dosage was, in many cases, inconsistent with the recommended dosage schedule for children. Conclusion Deployment of ALu has significantly changed community level perceptions of anti-malarial treatment. However, mothers continue to delay seeking care before accessing ALu, limiting the impact of highly subsidized rollout of the drug. Implementation of ACT-based treatment guidelines must be complemented with educational campaigns to insure that mothers seek prompt help for their children within 24 hours of the onset of fever. Improved communication between health care providers and mothers of sick children can facilitate better adherence to ALu's recommended dosage. Community level interpretations of anti-malarials are multifaceted; integrating knowledge of local beliefs and practices surrounding consumption of anti-malarials into programmatic goals can help to significantly improve malaria control interventions.

  4. Medium and long-term adherence to postabortion contraception among women having experienced unsafe abortion in Dar es Salaam, Tanzania

    DEFF Research Database (Denmark)

    Rasch, Vibeke; Yambesi, Fortunata; Massawe, Siriel

    2008-01-01

    BACKGROUND: Postabortion contraceptive service is considered an effective means in addressing the problem of unsafe abortion; in spite this fact this component remains one of the weakest parts of postabortion care. In this context, the paper aims to describe the impact of a postabortion contracep......BACKGROUND: Postabortion contraceptive service is considered an effective means in addressing the problem of unsafe abortion; in spite this fact this component remains one of the weakest parts of postabortion care. In this context, the paper aims to describe the impact of a postabortion...... contraceptive service intervention among women admitted with complications from unsafe abortions and to explore the women's long-term contraceptive adherence. METHODS: 392 women having experienced unsafe abortion were identified by an empathetic approach and offered postabortion contraceptive service, which...... included counselling on HIV and condom use. Questionnaire interviews about contraceptive use were conducted at the time of inclusion and 12 months after the abortion. Additionally, in-depth interviews were performed 6-12 months after the abortion. RESULTS: Eighty-nine percent of the women accepted...

  5. Prevalence and risk factors of cervical squamous intraepithelial lesions among HIV-infected women in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Liu, Enju; McCree, Renicha; Mtisi, Expeditho; Fawzi, Wafaie W; Aris, Eric; Lema, Irene A; Hertzmark, Ellen; Chalamilla, Guerino; Li, Nan; Vermund, Sten H; Spiegelman, Donna

    2016-03-01

    To determine the prevalence and predictors of cervical squamous intraepithelial lesions (SIL) among HIV-infected women in Tanzania, a cross-sectional study was conducted among HIV-infected women at HIV care and treatment clinics. A Papanicolaou (Pap) smear was used as a screening tool for detection of cervical SIL. From December 2006 to August 2009, 1365 HIV-infected women received cervical screening. The median age was 35 (interquartile range [IQR]: 30-42) years, and the median CD4 + cell count was 164 (IQR: 80-257) cells/mm(3). The prevalence of cervical SIL was 8.7% (119/1365). In multivariate analysis, older age (≥50 versus 30-cervical inflammation (PR, 1.73; 95% CI, 1.16-2.60, p = 0.008) were associated with an increased risk of cervical SIL. Women with advanced WHO HIV disease stage (IV versus I/II: PR, 3.45; 95% CI, 1.35-8.85, p for trend = 0.01) had an increased risk for high-grade SIL. In resource-limited settings where it is not feasible to provide cervical cancer prevention services to all HIV-infected women, greater efforts should focus on scaling-up services among those who are older than 50 years, with lower CD4 cell counts and advanced HIV disease stage.

  6. Experiences and Impact of Stigma and Discrimination among People on Antiretroviral Therapy in Dar es Salaam: A Qualitative Perspective

    Directory of Open Access Journals (Sweden)

    Maisara Mhode

    2016-01-01

    Full Text Available Background. The impact of stigma on adherence to antiretroviral therapy (ART has been less studied in Tanzania. Recent studies indicate that people on ART still experience stigma. Qualitative information on the subject matter is especially insufficient. Objective. This paper reports on the dimensions of stigma and discrimination and their impact on adherence to ART as experienced by people living with HIV (PLHIV. Design. A phenomenological approach was used to gather information on the lived experiences of stigma and discrimination. The sample size was determined according to the saturation principle. Results. Respondents experienced different forms of HIV-related stigma such as verbal, social, and perceived stigma. Various forms of discrimination were experienced, including relational discrimination, mistreatment by health care workers, blame and rejection by spouses, and workplace discrimination. HIV-related stigma and discrimination compromised ART adherence by reinforcing concealment of HIV status and undermining social suppport. Conclusion. After nearly a decade of increasing the provision of ART in Tanzania, PLHIV still experience stigma and discrimination; these experiences still appear to have a negative impact on treatment adherence. Efforts to reduce stigma and discrimination remain relevant in the ART period and should be given more impetus in order to maximize positive treatment outcomes.

  7. Adolescent girls, illegal abortions and "sugar-daddies" in Dar es Salaam: vulnerable victims and active social agents

    DEFF Research Database (Denmark)

    Silberschmidt, Margrethe; Rasch, V

    2001-01-01

    are not aware about their right to such services. The paper concludes that the vulnerability of adolescent girls increases without the recognition that sexuality education and contraceptive services do not constitute a licence to practice illicit sex - but rather a means to create more mature and responsible...

  8. The extension of Ubungo power plant in Dar es Salaam, Tanzania, to a combined cycle - A prestudy

    Energy Technology Data Exchange (ETDEWEB)

    Grinneland, L.; Oehrstroem, K.

    1996-05-01

    The report deals with the consequences concerning a future extension of Ubungo Power Plant. Today the power plant consists of four gas turbines, two of model General Electric LM6000 and two of model ABB Stal GT10 of which the latter were the ones focused on. In the report four different applications are presented; Simple two pressure system, Two pressure system with reheat, Two pressure system with heat exchange between feedwater and condensate, and single pressure system with an additional evaporating loop. The calculations are divided into three sections; thermodynamic calculations, calculations of the heat exchanger surface areas, and economic calculations. From the thermodynamic calculations the applications with the highest thermal efficiency was selected. The power output increased with about 55% and the thermal efficiency of the complete combined cycle is 48.2%. This is, of course, a theoretical value calculated without consideration to a number of losses that will decrease both the power output and the thermal efficiency. At part load (50% load assumed, i.e. one gas turbine is operating) the thermal efficiency is 46.7%. The economic calculations indicated that the extension is highly worthwhile in an economic point of view; both cases studied have a payback time of less than six years for full load operation, provided that the charging system which is to be imposed by the World Bank has come into force. 18 refs, 33 figs

  9. Conference on Resource Sharing in Southern and Central Africa (Dar-es-Salaam, Tanzania, December 16-19, 1985). Final Report.

    Science.gov (United States)

    United Nations Educational, Scientific and Cultural Organization, Paris (France). General Information Programme.

    This document summarizes the activities of a conference held at the Institute of Finance Management in Tanzania on information resource sharing in Southern and Central Africa. Delegates and observers from Lesotho, Swaziland, Mozambique, Botswana, Zimbabwe, Malawi, Zambia, and Tanzania attended the conference. The 15 participants, 8 sponsored by…

  10. Oral manifestations of HIV infection in children and adults receiving highly active anti-retroviral therapy [HAART] in Dar es Salaam, Tanzania.

    NARCIS (Netherlands)

    Hamza, O.; Matee, M.I.N.; Simon, E.N.; Kikwilu, E.; Moshi, M.J.; Mugusi, F.; Mikx, F.H.M.; Verweij, P.E.; Ven, A.J.A.M. van der

    2006-01-01

    ABSTRACT: BACKGROUND: The aim of the study was to compare the prevalence and types of HIV-related oral lesions between children and adult Tanzanian patients on HAART with those not on HAART and to relate the occurrence of the lesions with anti-HIV drug regimen, clinical stage of HIV disease and CD4+

  11. Towards spatial justice in urban health services planning : A spatial-analytic GIS-based approach using Dar es Salaam, Tanzania as a case study

    NARCIS (Netherlands)

    Amer, S.

    2007-01-01

    The overarching aim of this study is to develop a GIS-based planning approach that contributes to equitable and efficient provision of urban health services in cities in sub-Saharan Africa. Its prime concern is with (i) the identification of theoretical and methodological constructs that can be used

  12. Clinical presentation, diagnostic evaluation, treatment and diagnoses of febrile children presenting to the emergency department at Muhimbili national hospital in Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    F.H. Ringo*

    2013-12-01

    Conclusion: A wide range of presentations and management were documented. There was a high rate of positive diagnostic test results. Malaria and pneumonia were top diagnoses, but a wide range of infections were diagnosed.

  13. Hepatitis A, B and C viral co-infections among HIV-infected adults presenting for care and treatment at Muhimbili National Hospital in Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Matee Mecky

    2008-12-01

    Full Text Available Abstract Background Tanzania is currently scaling-up access to anti-retro viral therapy (ART to reach as many eligible persons as possible. Hepatitis viral co-infections are known to influence progression, management as well as outcome of HIV infection. However, information is scarce regarding the prevalence and predictors of viral hepatitis co-infection among HIV-infected individuals presenting at the HIV care and treatment clinics in the country. Methods A cross-sectional study conducted between April and September 2006 enrolled 260 HIV-1 infected, HAART naïve patients aged ≥18 years presenting at the HIV care and treatment clinic (CTC of the Muhimbili National Hospital (MNH. The evaluation included clinical assessment and determination of CD4+ T-lymphocyte count, serum transaminases and serology for Hepatitis A, B and C markers by ELISA. Results The prevalence of anti HAV IgM, HBsAg, anti-HBc IgM and anti-HCV IgG antibodies were 3.1%, 17.3%, 2.3% and 18.1%, respectively. Dual co-infection with HBV and HCV occurred in 10 individuals (3.9%, while that of HAV and HBV was detected in two subjects (0.8%. None of the patients had all the three hepatitis viruses. Most patients (81.1% with hepatitis co-infection neither had specific clinical features nor raised serum transaminases. History of blood transfusion and jaundice were independent predictors for HBsAg and anti-HBc IgM positivity, respectively. Conclusion There is high prevalence of markers for hepatitis B and C infections among HIV infected patients seeking care and treatment at MNH. Clinical features and a raise in serum alanine aminotransferase were of limited predictive values for the viral co-infections. Efforts to scale up HAART should also address co-infections with Hepatitis B and C viruses.

  14. Social reactions to rape: experiences and perceptions of women rape survivors and their potential support providers in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Muganyizi, Projestine S; Hogan, Nora; Emmelin, Maria; Lindmark, Gunilla; Massawe, Siriel; Nystrom, Lennarth; Axemo, Pia

    2009-01-01

    Social reactions to rape are socioculturally determined and have a strong influence on the coping and recovery of the survivor. The existing knowledge on social reactions emanates from Western countries with limited research attention on non-Western populations, particularly sub-Saharan Africa. We aimed to establish the types and perceptions of social reactions that are expressed to rape survivors and people's intentions to express them to survivors of varied social backgrounds in Tanzania. Using triangulation of research methods, experiences of social reactions among rape survivors (n = 50) and nurses (n = 44) from a community in Tanzania were explored, and the intentions to express typical social reactions to rape survivors of different social backgrounds were established from a representative community sample (n = 1,505). Twelve typical social reactions were identified with the positive reactions more commonly mentioned than the negative reactions. Nondisclosure of rape events and distracting the survivor from the event were perceived as both positive and negative. A commercial sex worker was most vulnerable to negative reactions. The cultural influences of social reactions and implications for practical applicability of the results are discussed.

  15. Cervical cytological changes in HIV-infected patients attending care and treatment clinic at Muhimbili National Hospital, Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Mwakigonja Amos R

    2012-02-01

    Full Text Available Abstract Background Tanzania is among Sub-Saharan countries mostly affected by the HIV and AIDS pandemic, females being more vulnerable than males. HIV infected women appear to have a higher rate of persistent infection by high risk types of human papillomavirus (HPV strongly associated with high-grade squamous intraepithelial lesions (HSIL and invasive cervical carcinoma. Furthermore, although HIV infection and cervical cancer are major public health problems, the frequency and HIV/HPV association of cervical cancer and HSIL is not well documented in Tanzania, thus limiting the development of preventive and therapeutic strategies. Methods A prospective unmatched, case-control study of HIV-seropositive, ≥ 18 years of age and consenting non-pregnant patients attending the care and treatment center (CTC at Muhimbili National Hoospital (MNH as cases was done between 2005 and 2006. HIV seronegative, non-pregnant and consenting women recruited from the Cervical Cancer Screening unit (CCSU at ORCI were used as controls while those who did not consent to study participation and/or individuals under Results A total of 170 participants from the two centers were recruited including 50 HIV-seronegative controls were from the CCSU. Ages ranged from 20-66 years (mean 40.5 years for cases and 20-69 years (mean 41.6 years for controls. The age group 36-45 years was the most affected by HIV (39.2%, n = 47. Cervicitis, squamous intraepithelial lesions (SIL and carcinoma constituted 28.3% (n = 34, 38.3% (n = 46 and 5.8% (n = 7 respectively among cases, and 28% (n = 14, 34% (n = 17 and 2% (n = 1 for controls, although this was not statistically significant (P-value = 0.61. IHC showed that p53 was not detectable in HPV + Pap smears and cell blocks indicating possible degradation. Conclusions The frequency of SIL and carcinoma appeared to be higher among HIV-infected women on HAART compared to seronegative controls and as expected increased with age. HIV seropositive patients appeared to present earlier with SIL compared to those HIV seronegative suggesting a role of HIV in altering the natural history of HPV infection and cervical lesions. The absence of p53 immunoreactivity in HPV + lesions is indicative of the ability of HPV E6 proteins to interact with the tumor suppressor gene and pave way for viral-induced oncogenesis in the studied Tanzanian women.

  16. Glycaemic control in type 1 diabetes mellitus among children and adolescents in a resource limited setting in Dar es Salaam - Tanzania

    OpenAIRE

    Noorani, Mariam; Ramaiya, Kaushik; Manji, Karim

    2016-01-01

    Background Type 1 Diabetes Mellitus is a rapidly growing problem in Tanzania. Children and adolescents with type 1 diabetes have previously been found to have poor glycaemic control and high prevalence of complications. Strict glycaemic control reduces the incidence and progression of chronic complications. The aim of this study was to identify the factors associated with glycaemic control among children and adolescents. Methods A cross sectional study was done at the diabetes clinic for chil...

  17. The problem of illegally induced abortion: results from a hospital-based study conducted at district level in Dar es Salaam

    DEFF Research Database (Denmark)

    Rasch, V; Muhammad, H; Urassa, E

    2000-01-01

    women with IA and 241 with SA. They were compared with 307 AC women. IA women were significantly younger, more often better educated, unmarried, nulliparous and students than AC women. Regarding civil-status, educational level, proportion of nullipara and proportion of students, SA patients were similar...

  18. Cost and cost-effectiveness of community based and health facility based directly observed treatment of tuberculosis in Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Robberstad Bjarne

    2005-07-01

    Full Text Available Abstract Background Identifying new approaches to tuberculosis treatment that are effective and put less demand to meagre health resources is important. One such approach is community based direct observed treatment (DOT. The purpose of the study was to determine the cost and cost effectiveness of health facility and community based directly observed treatment of tuberculosis in an urban setting in Tanzania. Methods Two alternative strategies were compared: health facility based directly observed treatment by health personnel and community based directly observed treatment by treatment supervisors. Costs were analysed from the perspective of health services, patients and community in the year 2002 in US $ using standard methods. Treatment outcomes were obtained from a randomised-controlled trial which was conducted alongside the cost study. Smear positive, smear negative and extra-pulmonary TB patients were included. Cost-effectiveness was calculated as the cost per patient successfully treated. Results The total cost of treating a patient with conventional health facility based DOT and community based DOT were $ 145 and $ 94 respectively. Community based DOT reduced cost by 35%. Cost fell by 27% for health services and 72% for patients. When smear positive and smear negative patients were considered separately, community DOT was associated with 45% and 19% reduction of the costs respectively. Patients used about $ 43 to follow their medication to health facility which is equivalent to their monthly income. Indirect costs were as important as direct costs, contributing to about 49% of the total patient's cost. The main reason for reduced cost was fewer number of visits to the TB clinic. Community based DOT was more cost-effective at $ 128 per patient successfully treated compared to $ 203 for a patient successfully treated with health facility based DOT. Conclusion Community based DOT presents an economically attractive option to complement health facility based DOT. This is particularly important in settings where TB clinics are working beyond capacity under limited resources.

  19. Adolescent girls with illegally induced abortion in Dar es Salaam: the discrepancy between sexual behaviour and lack of access to contraception

    DEFF Research Database (Denmark)

    Rasch, V; Silberschmidt, Margrethe; Mchumvu, Y

    2000-01-01

    that gave them the right to seek family planning services and in practice these services are not being provided. There is a need for youth-friendly family planning services and to make abortion safe and legal, in order to reduce unwanted pregnancies and abortion-related complications and deaths among...

  20. Medical evaluation abnormalities in acute psychotic patients seen at the emergency department of Muhimbili national hospital in Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    S.G. Yusuf*

    2013-12-01

    Conclusions: In our cohort, history and physical examination findings were not sufficient to rule out serious medical conditions among patients presenting with acute psychosis. The observed rate of laboratory abnormalities was higher than previously published rates from high-resource settings. Based on our findings, patients presenting with psychosis to an acute care facility in this region should be evaluated with physical examination and laboratory studies to rule out serious underlying medical pathology.

  1. Assessment of adaptation strategies to flooding: A comparative study between informal settlements of Keko Machungwa in Dar es Salaam, Tanzania and Sangkrah in Surakarta, Indonesia

    Directory of Open Access Journals (Sweden)

    Tumpale Sakijege

    2014-03-01

    Full Text Available A large number of informal settlements in developing countries are located in high risk areas(low-lying lands and on river banks. This situation is caused by poverty and the inabilityof authorities to supply planned plots for building to meet demands of the growing urbanpopulations. Informal settlements have, in turn, triggered disaster risks, flooding being just oneof them. As a way of reducing impacts of flooding, residents in informal settlements have resortedto the use of structural adaptation strategies. Despite these efforts, the vulnerability of peopleand properties in informal settlements is increasing. This article aimed to provide an answer as towhy this is the case, by assessing and comparing the technical suitability of adaptation strategiesto flooding in the informal settlements of Sangkrah and Keko Machungwa and recommendingmeasures for improvement. Household interviews, physical observation (visual inspections ofsigns of damage and deterioration, measurements of height of physical adaptation strategies,mapping, photographing, and in-depth interviews were the key methods employed. Generally,in both cases, it was determined that flood mitigation and risk minimisation measures throughstructural adaptation strategies were hardly achieved at the household level, as adaptationstrategies were constructed with little or no attention to acceptable technical considerations.However, when levels of compliance to technical considerations in the construction of houseswere compared between the two cases, they were found to be slightly higher in Sangkrah thanin Keko Machungwa. Residents in Sangkrah demonstrated a slight difference, especially in theuse of reinforced concrete (4.3% for constructing a building’s foundation, as well as in the useof ceramics (72.9% to construct the floor. In order to deliver technically suitable adaptationstrategies, efforts need to be directed toward: regulating and controlling the construction ofstructures for adaptation, enhancing individual coping capacity, deployment of a workforcetrained in disaster risk and management and enforcement of relevant urban planning andenvironmental management laws in managing risky areas.

  2. Challenges of caring for children with mental disorders: Experiences and views of caregivers attending the outpatient clinic at Muhimbili National Hospital, Dar es Salaam - Tanzania

    Directory of Open Access Journals (Sweden)

    Ambikile Joel

    2012-07-01

    Full Text Available Abstract Background It is estimated that world-wide up to 20 % of children suffer from debilitating mental illness. Mental disorders that pose a significant concern include learning disorders, hyperkinetic disorders (ADHD, depression, psychosis, pervasive development disorders, attachment disorders, anxiety disorders, conduct disorder, substance abuse and eating disorders. Living with such children can be very stressful for caregivers in the family. Therefore, determination of challenges of living with these children is important in the process of finding ways to help or support caregivers to provide proper care for their children. The purpose of this study was to explore the psychological and emotional, social, and economic challenges that parents or guardians experience when caring for mentally ill children and what they do to address or deal with them. Methodology A qualitative study design using in-depth interviews and focus group discussions was applied. The study was conducted at the psychiatric unit of Muhimbili National Hospital in Tanzania. Two focus groups discussions (FGDs and 8 in-depth interviews were conducted with caregivers who attended the psychiatric clinic with their children. Data analysis was done using content analysis. Results The study revealed psychological and emotional, social, and economic challenges caregivers endure while living with mentally ill children. Psychological and emotional challenges included being stressed by caring tasks and having worries about the present and future life of their children. They had feelings of sadness, and inner pain or bitterness due to the disturbing behaviour of the children. They also experienced some communication problems with their children due to their inability to talk. Social challenges were inadequate social services for their children, stigma, burden of caring task, lack of public awareness of mental illness, lack of social support, and problems with social life. The economic challenges were poverty, child care interfering with various income generating activities in the family, and extra expenses associated with the child’s illness. Conclusion Caregivers of mentally ill children experience various psychological and emotional, social, and economic challenges. Professional assistance, public awareness of mental illnesses in children, social support by the government, private sector, and non-governmental organizations (NGOs are important in addressing these challenges.

  3. Nurse-led educational campaign on blood borne pathogens and proper sharps disposal at an urban tertiary hospital in Dar Es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    A. Otieno

    2013-12-01

    Conclusion: The results of this study suggest that even with very high levels of immediate and delayed retention of educational content as measured by exam, the impact of an educational intervention on behavioural change may be much more short-lived. This has implications regarding the need for continuous education to support for workplace safety campaigns.

  4. Absence of kdr resistance alleles in the Union of the Comoros, East Africa [v1; ref status: indexed, http://f1000r.es/5fw

    Directory of Open Access Journals (Sweden)

    Yoosook Lee

    2015-06-01

    Full Text Available Knockdown resistance (kdr and CYP9K1 genotypes were detected by a MOLDI-TOF based SNP genotyping assay (Sequenom iPLEX in samples of Anopheles gambiae collected at 13 sites throughout the Union of the Comoros and Dar es Salaam, Tanzania during February and March 2011. All A. gambiae specimens collected in the Comoros were homozygous for the susceptible kdr alleles (+/+ while 96% of A. gambiae from Dar es Salaam were homozygous for the East African kdr resistant genotype (E/E. In contrast, all specimens from Dar es Salaam and the Comoros were homozygous for the cyp3 allele (c3/c3 at the CYP9K1 locus; the locus has been implicated in metabolic resistance against pyrethroid insecticides in West Africa. All specimens had typical A. gambiae genotypes for SNPs within the divergence Islands on all three chromosomes. Although further spatial and temporal studies are needed, the distribution of kdr genotypes between the Comoros and Tanzania further supports isolation of the Comoros populations from A. gambiae populations on mainland Africa.

  5. OSL dating of the Aterian levels at Dar es-Soltan I (Rabat, Morocco) and implications for the dispersal of modern Homo sapiens

    Science.gov (United States)

    Barton, R. N. E.; Bouzouggar, A.; Collcutt, S. N.; Schwenninger, J.-L.; Clark-Balzan, L.

    2009-09-01

    The Aterian is a distinctive Middle Palaeolithic industry which is very widely spread across North Africa. Its dating and significance have been debated for nearly a century. Renewed interest in the Aterian has arisen because of a recent proposal that its development and spread may be linked to the dispersal of anatomically modern humans. The industry contains technological innovations such as thin bifacially flaked lithic points and pedunculates as well as evidence for personal ornaments and use of red ochre. Such markers as shell beads are believed to be indicative of symbolic behaviour. Dar es-Soltan I on the Atlantic coast of Morocco contains a thick sequence of Aterian deposits that were thought to represent the later stages of development of this industry. New Optically Stimulated Luminescence dates and geomorphological study indicate a much older sequence and so far the earliest yet recorded ages for the Aterian. They suggest an appearance in the Maghreb region during MIS (Marine Isotope Stage) 5.

  6. The costs of providing antiretroviral therapy services to HIV-infected individuals presenting with advanced HIV disease at public health centres in Dar es Salaam, Tanzania: Findings from a randomised trial evaluating different health care strategies

    Science.gov (United States)

    Kimaro, Godfather Dickson; Mfinanga, Sayoki; Simms, Victoria; Kivuyo, Sokoine; Bottomley, Christian; Hawkins, Neil; Harrison, Thomas S.; Jaffar, Shabbar; Guinness, Lorna

    2017-01-01

    Background Understanding the costs associated with health care delivery strategies is essential for planning. There are few data on health service resources used by patients and their associated costs within antiretroviral (ART) programmes in Africa. Material and methods The study was nested within a large trial, which evaluated screening for cryptococcal meningitis and tuberculosis and a short initial period of home-based adherence support for patients initiating ART with advanced HIV disease in Tanzania and Zambia. The economic evaluation was done in Tanzania alone. We estimated costs of providing routine ART services from the health service provider's perspective using a micro-costing approach. Incremental costs for the different novel components of service delivery were also estimated. All costs were converted into US dollars (US$) and based on 2012 prices. Results Of 870 individuals enrolled in Tanzania, 434 were enrolled in the intervention arm and 436 in the standard care/control arm. Overall, the median (IQR) age and CD4 cell count at enrolment were 38 [31, 44] years and 52 [20, 89] cells/mm3, respectively. The mean per patient costs over the first three months and over a one year period of follow up following ART initiation in the standard care arm were US$ 107 (95%CI 101–112) and US$ 265 (95%CI 254–275) respectively. ART drugs, clinic visits and hospital admission constituted 50%, 19%, and 19% of the total cost per patient year, while diagnostic tests and non-ART drugs (co-trimoxazole) accounted for 10% and 2% of total per patient year costs. The incremental costs of the intervention to the health service over the first three months was US$ 59 (p<0.001; 95%CI 52–67) and over a one year period was US$ 67(p<0.001; 95%CI 50–83). This is equivalent to an increase of 55% (95%CI 51%–59%) in the mean cost of care over the first three months, and 25% (95%CI 20%–30%) increase over one year of follow up. PMID:28234969

  7. Assessment of the experiences and coping strategies of people working in the informal sector in their quest to access health care services: the case of Dar es Salaam, Tanzania.

    Science.gov (United States)

    Munga, Michael A; Gideon, Gilbert M

    2009-02-01

    Addressing inequities in health care provision and financing has been at the center stage of Health Sector Reform (HSR) discussions since the early 1980s. The poor, women, and informal health sector workers in most developing countries are rarely covered by formal health insurance mechanisms that are meant to ensure access to essential health services. They are also sidelined in formal banking and credit systems due to their being predominantly low income earners, with little resources to meet eligibility criteria for borrowing and also to be considered creditworthy. In light of this fact, the present paper analyzes both quantitative and qualitative data in an attempt to explore and discuss the experiences and coping strategies of women and men employed in the informal sector economy in their daily attempts to access health care services. The paper employs Malaria as a tracer disease and gender as a unit of analysis. Analysis indicated the significance, as perceived by interviewees, of both informal credit networks and formal insurance and banking systems as important shock-absorbers for vulnerable populations in their struggle to access basic health services in times of need. The paper further highlights and discusses diverse coping strategies that households employ in dealing with illness-related costs and a greater willingness to be integrated into both formal and informal financial mechanisms. The paper finally concludes that the government must take the following steps: 1) enhance existing formal and communitybased initiatives to make them sustainable, 2) devise ways to reduce the lack of flexibility in membership requirements for insurance schemes/financial institutions, and 3) reduce perverse incentives inherent in the health system that may prevent people from seeking membership in available insurance mechanisms. In addition, deliberate steps must be taken by the government to employ 'targeted measures' to ensure that health care access is improved and sustained particularly for vulnerable populations.

  8. La "capacidad vial" del plan regulador chileno, ¿es lo suficientemente buena para dar forma a un entorno edificado sostenible?/ The "road capacity" of the chilean master plan is it good enough for shaping a sustainable built environment?

    Directory of Open Access Journals (Sweden)

    Cárdenas Jirón, Luz Alicia

    2000-03-01

    Full Text Available The "road capacity" of the Chilean Master Plan is a tool developed to measure the capacity of streets in terms of supporting the size of vehicle flow. This tool considers topics such as land use, population density and street width. The purpose of this technique is to incorporate it to the Master Plan, as a town planning instrument, so as to cope with traffic forecasting and congestion. However, the technique does not embrace any sustainability concept, this is due to a disregard of any district ´s social or environmental needs. Therefore a sustainable urban development would doubtfully be reached. It is argued that some other approaches are required for shaping a sustainable built environment in which it is understood that the streets are a public space for people rather than a platform for moving vehicles only. This means, to promote accessibility as well as mobility. In this paper the author reviews borrowed concepts such as "carrying capacity" and "environmental capacity" from bioregionalist and ecological disciplines using a case study in outskirts of Santiago´s metro area./La "capacidad vial" del Plan Regulador chileno es una herramienta desarrollada para medir la capacidad de las calles en términos de apoyar el tamaño del flujo de vehículos. Esta herramienta considera temas como el uso de la tierra, la densidad de población y ancho de la calle. El propósito de esta técnica es su incorporación al Plan Maestro, como un instrumento de planificación de la ciudad, con el fin de hacer frente a la previsión del tráfico y la congestión. Sin embargo, la técnica no incluye ningún concepto de sostenibilidad. Por lo tanto un desarrollo urbano sostenible dudosamente sería alcanzado. Se argumenta que algunos otros enfoques son necesarios para dar forma a un medio ambiente sostenible integrado, en el que se entiende que las calles son un espacio público para las personas en lugar de una plataforma para mover los vehículos solamente

  9. A Layered Social and Operational Network Analysis

    Science.gov (United States)

    2007-03-01

    method for incorporating triad relationships, time, and location into social network studies. Utilizing the basic eigenvector centrality, the method...were carried out by two cooperating al-Qaeda cells against the US embassies in Nairobi, Kenya and Dar es Salaam, Tanzania (Champagne, 2005). This...Abdullah Mohammed, Azzam (Suicide Bomber) • Dar es Salaam, Tanzania Cell: Fahad Mohammed Ally Msalam, Mustafa Mohammed Fadhil, Khalfan Khamis

  10. 2002 Willapa Bay LiDAR Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA contracted with Spencer B. Gross, Inc. (SBG) to obtain airborne LiDAR of Willapa Bay, Washington during low tide conditions. The LiDAR data was processed to...

  11. Tri-Lateral Noor al Salaam High Concentration Solar Central Receiver Program

    Energy Technology Data Exchange (ETDEWEB)

    Blackmon, James B

    2008-03-31

    This report documents the efforts conducted primarily under the Noor al Salaam (“Light of Peace”) program under DOE GRANT NUMBER DE-FC36-02GO12030, together with relevant technical results from a closely related technology development effort, the U.S./Israel Science and Technology Foundation (USISTF) High Concentration Solar Central Receiver program. These efforts involved preliminary design, development, and test of selected prototype power production subsystems and documentation of an initial version of the system definition for a high concentration solar hybrid/gas electrical power plant to be built in Zaafarana, Egypt as a first step in planned commercialization. A major part of the planned work was halted in 2007 with an amendment in October 2007 requiring that we complete the technical effort by December 31, 2007 and provide a final report to DOE within the following 90 days. This document summarizes the work conducted. The USISTF program was a 50/50 cost-shared program supported by the Department of Commerce through the U.S./Israel Science and Technology Commission (USISTC). The USISTC was cooperatively developed by President Clinton and the late Prime Minister Rabin of Israel "to encourage technological collaboration" and "support peace in the Middle East through economic development". The program was conducted as a follow-on effort to Israel's Magnet/CONSOLAR Program, which was an advanced development effort to design, fabricate, and test a solar central receiver and secondary optics for a "beam down" central receiver concept. The status of these hardware development programs is reviewed, since they form the basis for the Noor al Salaam program. Descriptions are provided of the integrated system and the major subsystems, including the heliostat, the high temperature air receiver, the power conversion unit, tower and tower reflector, compound parabolic concentrator, and the master control system. One objective of the USISTF program was to conduct

  12. Es oliva

    OpenAIRE

    Feilbach, Timo; Giménez Cortés, Rodrigo; Martínez Espert, Laura; Sánchez Gutierrez, Javier

    2015-01-01

    Es.Oliva, S.L” es una empresa que se dedica a la comercialización de aceite de oliva ecológico hacia tierras alemanas, principalmente por el área de Dusseldorf, y posteriormente ampliando diversas zonas. A través de la obtención de las materias primas (el envase revolucionario y el aceite de oliva), se procesa para el embotellamiento y posterior distribución por las tiendas Gourmet del área alemana comentada anteriormente. Toda esta idea surge por la falta de aceite de oliva español en el...

  13. 2006 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Lewis County, WA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. collected Light Detection and Ranging (LiDAR) data of Western Lewis County for the Puget Sound LiDAR Consortium. This data set covers...

  14. 2015 Puget Sound LiDAR Consortium (PSLC) LiDAR: WA DNR Lands (P2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In June 2014, WSI, a Quantum Spatial Inc. (QSI) company, was contracted by the Puget Sound LiDAR Consortium (PSLC) to collect Light Detection and Ranging (LiDAR)...

  15. 2015 Puget Sound LiDAR Consortium (PSLC) LiDAR: WA DNR Lands (P1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In June 2014, WSI, a Quantum Spatial Inc. (QSI) company, was contracted by the Puget Sound LiDAR Consortium (PSLC) to collect Light Detection and Ranging (LiDAR)...

  16. 2013 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Tulalip Partnership

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In October 2012, WSI (Watershed Sciences, Inc.) was contracted by the Puget Sound LiDAR Consortium (PSLC)to collect Light Detection and Ranging (LiDAR) data on a...

  17. 2013 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Nooksack

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In July 2012, WSI (Watershed Sciences, Inc.) was contracted by the Puget Sound LiDAR Consortium (PSLC) to collect Light Detection and Ranging (LiDAR) data on a...

  18. 2013 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Saddle Mountain

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In October 2013, WSI, a Quantum Spatial Company (QSI), was contracted by the Puget Sound LiDAR Consortium (PSLC) to collect Light Detection and Ranging (LiDAR) data...

  19. 2009 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Lewis County, Washington

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WSI) collected Light Detection and Ranging (LiDAR) data for the Lewis County survey area for the Puget Sound LiDAR Consortium. This data...

  20. 2011 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Quinault River Basin

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WSI) collected Light Detection and Ranging (LiDAR) data on the Quinault River Basin survey area for the Puget Sound LiDAR Consortium and...

  1. 2014 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Willapa Valley (Delivery 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In January, 2014 WSI, a Quantum Spatial (QSI) company, was contracted by the Puget Sound LiDAR Consortium (PSLC) to collect Light Detection and Ranging (LiDAR) data...

  2. LiDAR remote sensing applied to forest resources assessment

    OpenAIRE

    Fernández-Landa, Alfredo

    2015-01-01

    Disponer de información precisa y actualizada de inventario forestal es una pieza clave para mejorar la gestión forestal sostenible y para proponer y evaluar políticas de conservación de bosques que permitan la reducción de emisiones de carbono debidas a la deforestación y degradación forestal (REDD). En este sentido, la tecnología LiDAR ha demostrado ser una herramienta perfecta para caracterizar y estimar de forma continua y en áreas extensas la estructura del bosque y las principales vari...

  3. Saginaw Bay, MI LiDAR

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TASK NAME:(NRCS) Saginaw Bay, MI LiDAR LiDAR Data Acquisition and Processing Production Task USGS Contract No. G10PC00057 Task Order No. G11PD01254 Woolpert Order...

  4. Hawaii DAR Dealer Reporting System Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In 2000 January, the Hawaii Division of Aquatic Resources (DAR) implemented a computerized data processing system for fish dealer data collected state-wide. Hawaii...

  5. Iowa LiDAR Mapping Project

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — This is collection level metadata for LAS and ASCII data files from the statewide Iowa Lidar Project. The Iowa Light Detection and Ranging (LiDAR) Project collects...

  6. USGS Atchafalaya 2 LiDAR

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of the Atchafalaya Basin project area. The entire survey area for Atchafalaya encompasses approximately...

  7. La Fageda: Otra empresa es posible...

    OpenAIRE

    2011-01-01

    El artículo presenta el caso de La Fageda, una empresa en la comarca gerundense de La Garrotxa, que se dedica a la producción de yogures y derivados lácteos. La Fageda es la tercera marca en penetración del mercado catalán y la de mayor crecimiento, con notables índices de rentabilidad. La singularidad de La Fageda consiste en dar empleo y asistir integralmente a personas con discapacidad psíquica o afectadas por trastornos mentales severos. El artículo presenta los orígenes de La Fageda, los...

  8. LiDAR data for the Delta Area of California

    Data.gov (United States)

    California Department of Resources — LiDAR data for the Delta Area of California from the California Department of Water Resources. Bare earth grids from LiDAR.This data is in ESRI Grid format with 2...

  9. Orienteerumiskaart vs. LiDAR / Marek Karm

    Index Scriptorium Estoniae

    Karm, Marek

    2012-01-01

    Bakalaureusetööst, mille eesmärk oli võrrelda orienteerumiskaardi reljeefi LiDAR-i andmete põhjal saadava reljeefimudeliga ning leida vastus küsimusele, kas o-kaart võib olla kasulik kooste- või kontrollmaterjal mistahes reljeefimudelile

  10. 2013 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Entiat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In October 2012, WSI (Watershed Sciences, Inc.) was contracted by the Puget Sound LiDARConsortium (PSLC) to collect Light Detection and Ranging (LiDAR) data for the...

  11. 2013 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Nooksack

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In July 2012, WSI (Watershed Sciences, Inc.) was contracted by the Puget Sound LiDARConsortium (PSLC) to collect Light Detection and Ranging (LiDAR) data on a...

  12. 2003 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Yakima County, Washington

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TerraPoint surveyed and created this data for the Puget Sound LiDAR Consortium under contract. The area surveyed is approximately 77 square miles and covers a...

  13. 2005 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Yakima County

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Terrapoint collected Light Detection and Ranging (LiDAR) data to complete the 2005 project for Yakima County. This project has partial coverage of Yakima County,...

  14. 2003 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Snohomish County, Washington

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TerraPoint surveyed and created this data for the Puget Sound LiDAR Consortium under contract. The area surveyed is approximately 167 square miles and covers a...

  15. 2005 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: North Puget Sound Lowlands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Terrapoint collected Light Detection and Ranging (LiDAR) data contributing to the Puget Sound Lowlands project of 2005. Arlington, City of Snohomish, Snohomish...

  16. 2012 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Upper Naches River, Washington

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WSI) collected Light Detection and Ranging (LiDAR) data of the Upper Naches River Valley and Nile Slide area of interest on September 30th,...

  17. 2005 Puget Sound LiDAR Consortium (PSLC) Bare-Earth Topographic LiDAR: Lynnwood

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Terrapoint collected Light Detection and Ranging (LiDAR) data contributing to the Puget Sound Lowlands project of 2005. Lynnwood, Snohomish County, Washington. This...

  18. 2007 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Sumpter, OR

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WS) collected Light Detection and Ranging (LiDAR) data for the USDA Forest Service on September 17, 2007. The project covers an 8-mile...

  19. 2011 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Rattlesnake

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WSI) collected Light Detection and Ranging (LiDAR) data on six days between September 15th and November 5th, and from November 6th ? 13th,...

  20. 2000 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Kitsap Peninsula, Washington

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TerraPoint surveyed and created this data for the Puget Sound LiDAR Consortium under contract. The area surveyed is approximately 1,146 square miles and covers part...

  1. 2005 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Olympic Peninsula

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Terrapoint collected Light Detection and Ranging (LiDAR) data for the Olympic Peninsula project of 2005, totaling approximately 114.59 sq mi: 24.5 for Clallam...

  2. 2005 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Lewis County

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Terrapoint collected Light Detection and Ranging (LiDAR) data for the Lewis County project of 2005. The project site covered approximately 223 square miles, divided...

  3. 2009 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Snohomish River Estuary

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WS) co-acquired Light Detection and Ranging (LiDAR) data and Truecolor Orthophotographs of the Snohomish River Estuary, WA on July 20 &...

  4. 2009 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Douglas Co.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WS) collected Light Detection and Ranging (LiDAR) data of the Douglas County PUD area of interest (AOI) east of Wenatchee, WA on May 2nd ?...

  5. La alternancia dar/hacer en construcciones con verbo de apoyo y nombre de comunicación

    Directory of Open Access Journals (Sweden)

    Begoña Sanromán Vilas

    2014-11-01

    Full Text Available En este artículo defendemos que la selección de un verbo de apoyo por parte del nombre que lo acompaña, dentro del contexto de una construcción con verbo de apoyo, se basa en criterios semánticos. En concreto, el objetivo del estudio será el de descubrir qué componente(s del significado del nombre determina(n la selección de dar y cuál(es, la de hacer, dos de los verbos de apoyo más frecuentes en español. Para llevar a cabo esta tarea, analizamos nombres pertenecientes al campo semántico de la comunicación verbal que pueden coocurrir con ambos verbos, dar y hacer (dar/hacer una sugerencia, y los contrastamos con otros dos grupos de nombres de comunicación: 1 los que se combinan con dar, pero rechazan *hacer (dar/*hacer una respuesta y 2 los coocurren con hacer, pero no con *dar (*dar/hacer una pregunta. En la comparación de los grupos trataremos de probar dos hipótesis: una que opera a nivel paradigmático, describiendo los vínculos semánticos entre los verbos de apoyo y los correspondientes verbos plenos y otra, a nivel sintagmático, analizando qué otros verbos, aparte de dar y/o hacer, constituyen la coocurrencia léxica restringida de los nombres de comunicación objeto de estudio.

  6. 2014 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Cedar River Watershed (Delivery 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In September 2013, WSI, a Quantum Spatial company (QSI), was contracted by the Puget Sound LiDAR Consortium (PSLC) to collect Light Detection and Ranging (LiDAR)...

  7. 2012 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Quinault River Watershed, Washington (Delivery 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WSI) collected Light Detection and Ranging (LiDAR) data on the Quinault watershed survey area for the Puget Sound LiDAR Consortium. This...

  8. Does participatory forest management promote sustainable forest utilisation in Tanzania?

    DEFF Research Database (Denmark)

    Treue, Thorsten; Ngaga, Y.M.; Meilby, Henrik;

    2014-01-01

    Over the past 20 years, Participatory Forest Management (PFM) has become a dominant forest management strategy in Tanzania, covering more than 4.1 million hectares. Sustainable forest use and supply of wood products to local people are major aims of PFM. This paper assesses the sustainability......-PFM). Extraction of products is intense in forests close to Dar es Salaam, regardless of management regime. Further from Dar es Salaam, harvesting levels in forests under PFM are, with one prominent exception, broadly sustainable. Using GIS data from 116 wards, it is shown that half of the PFM forests in Tanzania...

  9. Trapped in decline: A sociological analysis of economic life in Mgeta, Uluguru Mountains, Tanzania

    OpenAIRE

    Donge, van, J.K.

    1993-01-01

    The research for this thesis was carried out in Tanzania during the period 1985- 89 and focuses on the Mgeta division in the Uluguru mountains, Morogoro rural district. Research was also undertaken among migrants from the area living in Dar es Salaam where they traded in foodstuffs. I made a return visit to the area in November 1991 to look again at questions which arose during writing up. The research also reflects seven years' employment at the University of Dar es Salaam (1982-89). The Tan...

  10. Characterizing Lava Flows With LiDAR

    Science.gov (United States)

    Deligne, N. I.; Cashman, K. V.; Deardorff, N.; Dietterich, H. R.; House, P. K.; Soule, S.

    2009-12-01

    Digital elevation models (DEMs) have been used in volcanology in predictive modeling of lava flow paths, both for assessment of potential hazards and specific predictions of lava flow paths. Topographic analysis of a lava flow is potentially useful for mapping and quantifying flow surface morphologies, which in turn can be used to determine flow emplacement conditions, such as effusion rate, steadiness of flow, and interactions with pre-existing topography and surface water. However, this has been limited in application because of the coarse resolution of most DEMs. In recent years, use of Light Detection and Ranging (LiDAR) airborne laser altimetry, capable of producing high resolution (≤ 1 meter) DEMs, has become increasingly common in the geomorphic and mapping community. However, volcanologists have made little use of airborne LiDAR. Here we compare information obtained using field observations and standard (10 meter) DEMs against LiDAR high resolution DEMs to assess the usefulness, capabilities, and limitations of LiDAR as applicable to lava flows. We compare morphologic characteristics of five lava flows of different compositions, tectonic settings, flow extents, slopes, and eruption duration: (1) 1984 Mauna Loa lava flow, Hawaii; (2) December 1974 Kilauea lava flow, Hawaii; (3) c. 1600 ybp Collier Cone lava flow, central Oregon Cascades; (4) Holocene lava flows from the Sand Mountain volcanic chain, central Oregon Cascades; and (5) Pleistocene lava flows along the Owyhee River, eastern Oregon basin and range. These lava flows range in composition from basalt to andesite, and have eruption durations ranging from 6 hours (observed) to years (inferred). We measure channel width, levee and flow front heights, compression ridge amplitude, wavelength and tumuli dimensions, and surface roughness. For all but the smallest scale features, LiDAR is easily used to quantify these features, which often is impossible or technically challenging to do in the field, while

  11. UN ESTUDIANTE CONFLICTIVO PARA MUCHOS, ES EN REALIDAD UN PERSONAJE CON MUCHO QUE DAR

    Directory of Open Access Journals (Sweden)

    LEIDY NATALY MATEUS AGUILERA

    2010-08-01

    Full Text Available In this written presents a history that is repeat year to year for some educators that have as a goal to formation in aspects of type scientific and also as corresponding to social values; there is also a reflection that leads to evidence of bias, prejudice and the exclusion that is made, in some cases in the classroom, to students that present some difficulties, aspect that affects the formation of the student, the learning and evaluation. In the same way is presented as a suggestion the inclusion of values in the classroom regardless the area of knowledge, based on of a pedagogical model and psychological currents that allow establish academic links and reflections in the formation of human being.

  12. DAR: A Modern Institutional Repository with a Scalability Twist

    OpenAIRE

    Mikhail, Youssef; Adly, Noha; Nagi, Magdy

    2012-01-01

    The Digital Assets Repository (DAR) is an Institutional Repository developed at the Bibliotheca Alexandrina to manage the full lifecycle of a digital asset: its creation and ingestion, its metadata management, storage and archival in addition to the necessary mechanisms for publishing and dissemination. DAR was designed with a focus on integrating DAR with different sources of digital objects and metadata in addition to integration with applications built on top of the repository. As a modern...

  13. 2004 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Portland, Oregon

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The all returns ASCII files contain the X,Y,Z values of all the LiDAR returns collected during the survey mission. In addition each return also has a time stamp,...

  14. 2006 OSIP OGRIP Coastal Counties LiDAR Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 2006 OSIP digital LiDAR data was collected during the months of March and May (leaf-off conditions). The LiDAR covers the entire land area of the northern tier...

  15. 2006 OSIP OGRIP: Upland Counties LiDAR Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 2006 OSIP digital LiDAR data was collected during the months of March and May (leaf-off conditions). The LiDAR covers the entire land area of the northern tier...

  16. Darüşşifas Where Music Threapy was Practiced During Anatolian Seljuks and Ottomans

    Directory of Open Access Journals (Sweden)

    Gülşen Erdal

    2013-03-01

    ncesinde Türklerde nasıl kullanıldığını vurgulamak amacıyla ele alınmıştır. Buradan hareketle Kayseri Gevher Nesibe Tıp Medresesi (1206, Divriği Ulu Camii ve Darüşşifası (1228, Amasya Darüşşifası (1309, Fatih Darüşşifası (1470 Edirne Sultan II.Bayezid Darüşşifası (1488, Süleymaniye Tıp Medresesi ve Şifahanesi (1556 Enderun Hastanesi bu çalışmada müzikle tedavinin yapıldığı kurumlar arasında öne çıkanlar olarak incelenmiştir. Böylece Türk müziği makamları ve hastalıklar arasında kurulan ilişkiler Selçuklu ve Osmanlı Sanatı içinde müzikle tedavinin gerekleri düşünülerek inşa edilen bu yapıların yaşam amaçları ve müziğin iyileştirici gücünün vurgulanması amaçlanmıştır.La musicothérapie pratiquée pendant le règne des Seldjoukides d’Anatolie et des OttomansRésuméLa musicothérapie, l’une des plus anciennes méthodes de traitement connues, remonte à des milliers d’années. La musicothérapie turque pratiquée dans les hôpitaux ottomans et seldjoukides utilisait l’acoustique appropriée au traitement des troubles mentaux avec la lecture des livres des savants comme Avicenne, Râzî, Fârabî, Hasan Shuurî et Gevrekzade Hasan Efendi. Ainsi la musicothérapie et l’amélioration de la musicothérapie de manière exemplaire à l’époque des Ottomans et Seldjoukides est la première pratique sérieuse de la musicothérapie. Darüşşifa est l’un des noms donnés aux établissements médicaux et éducatifs qui confèrent au peuple des services de santé en fonction de la pratique et de l’observation et qui traitent les patients dans le monde turc et islamique. Les Turcs ont commencé à reconstruire différents bâtiments selon leurs possibilités en Anatolie. Dans une courte période, ils ont construit plusieurs types de constructions tels que caravansérails, médersas, mosquées, darüşşifas. En seldjoukide et ottoman darüşşifas, les sujets médicaux ont été acquis d

  17. LiDAR - An emerging tool for geological applications

    Science.gov (United States)

    Stoker, Jason M.

    2012-01-01

    Over the past five to ten years the use and applicability of light detection and ranging (LiDAR) technology has increased dramatically. As a result, more and more LiDAR data now are being collected across the country for a wide range of applications, and LiDAR currently is the technology of choice for high resolution terrain model creation, 3-D city and infrastructure modeling, forestry, and a wide range of scientific applications. LiDAR is a key technology for geological applications both within and outside the U.S. Geological Survey, and efforts are underway to try to collect high resolution LiDAR data for the entire United States (https://pubs.usgs.gov/fs/2012/3089/pdf/fs2012-3089.pdf).

  18. Geographical imagination and technological connectivity in East Africa

    DEFF Research Database (Denmark)

    Graham, Mark; Andersen, Casper; Mann, Laura

    2015-01-01

    The paper analyses and compares two transformative moments of technologically-mediated change in East Africa, the construction of the Uganda railway between Mombasa and Lake Victoria (1896-1903) and the introduction of fibre-optic cables that landed into the ports of Dar Es Salaam and Mombasa in ...

  19. Growth and poverty reduction in Tanzania

    DEFF Research Database (Denmark)

    Arndt, Channing; Demery, Lionel; McKay, Andy

    . The household survey data documents a limited reduction in consumption poverty over the period, and what poverty reduction there has been has mostly occurred in Dar es Salaam. Indicators of non-monetary poverty have gradually improved over the past 20 years but significant differences across the country remain....

  20. Oral candidiasis and hairy leukoplakia correlate with HIV infection in Tanzania

    DEFF Research Database (Denmark)

    Schiødt, M; Bakilana, P B; Hiza, J F

    1990-01-01

    We report a detailed study on oral lesions and their association with the WHO revised provisional case definition of AIDS as well as serologic signs of HIV infection among 186 patients in Dar Es Salaam, Tanzania. The patient material consisted of 39 hospitalized suspected AIDS patients, 44 medica...

  1. What We Do: Books for All.

    Science.gov (United States)

    Tanganyika Library Service (Tanzania).

    Services provided by the National Central Library in Dar es Salaam are: a fully organized public reference and lending service for both adults and children, a central book processing and supply unit, and a central advisory service. The Tanganyika Library Service also provides: branch libraries, rural mobile library services, loan of collections to…

  2. Food, Aid, and Education in East Africa: Repackaging the Conversation

    Science.gov (United States)

    Stambach, Amy

    2016-01-01

    This paper examines students' food perspectives in three rapidly diversifying contemporary contexts: a university setting in Kigali, Rwanda where students help to prepare Chinese dumplings; a school garden and canteen in Nairobi, Kenya where students jostle for bowls of beans and rice; and a fast-food restaurant in Dar es Salaam, Tanzania, where…

  3. Trapped in decline: a sociological analysis of economic life in Mgeta, Uluguru mountains Tanzania.

    NARCIS (Netherlands)

    Donge, van J.K.

    1993-01-01

    The research for this thesis was carried out in Tanzania during the period 1985- 89 and focuses on the Mgeta division in the Uluguru mountains, Morogoro rural district. Research was also undertaken among migrants from the area living in Dar es Salaam where they traded in foodstuffs. I made a return

  4. Criminal Acts Against Civil Aviation. Fiscal Year 1992

    Science.gov (United States)

    1992-01-01

    Aeromexico DC-9 Juarez/Mexico City, Mexico Brownsville, TX 01-05-68 Iran Air Unknown Tehran/ Mashad , Iran Unknown 02-13-68 Air Tanzania B-737 Dar es Salaam...04-05-48 Kuwait B-747 Bangkok, Thailand/Kuwait Mashad , Iran/Prisoner release Airways 05-12-68 CAAC (PRC) B-737 Xiamen/Guangzhou, PRC Republic of China

  5. Access, Use and Perceptions of Teachers and Students towards Mobile Phones as a Tool for Teaching and Learning in Tanzania

    Science.gov (United States)

    Kafyulilo, Ayoub

    2014-01-01

    This study explored the access, use and perceptions of teachers and students towards mobile phones as a tool for facilitating teaching and learning beyond the classroom walls. A total of 29 pre-service teachers and four college instructors from Dar es salaam University College of Education (DUCE) as well as 12 in-service teachers and 40 students…

  6. The Symbiotic Food System

    NARCIS (Netherlands)

    Wegerif, Marc; Hebinck, Paul

    2016-01-01

    This article is an analysis of the agri-food system that feeds most of the over four million residents of the fast growing city of Dar es Salaam in Tanzania. It is based on qualitative research that has traced the sources of some important foods from urban eaters back through retailers, processors a

  7. The genus Alfonsiella Waterston (Hymenoptera, Chalcidoidea, Agaonidae)

    NARCIS (Netherlands)

    Wiebes, J.T.

    1972-01-01

    This paper is a tribute to Prof. Dr. L. D. Brongersma, in remembrance of the years I served as his deputy in the Rijksmuseum van Natuurlijke Historie. The genus Alfonsiella was described by Waterston (1920) for A. fimbriata, a series of females of which were collected at Dar es Salaam, Tanganyika. I

  8. Special Operations: Reexamining the Case for a Sixth Service

    Science.gov (United States)

    2007-11-02

    strategic " Triad ," bombers and land-based missiles, with the Navy providing the third element using submarine-launched missiles.109 The U.S. led the...terrorist attack on the Khobar Towers in Riyadh, the embassy bombings in Nairobi, Kenya and Dar es Salaam, Tanzania, and the bombing of the USS Cole

  9. A longitudinal study on different models of postabortion care in Tanzania

    DEFF Research Database (Denmark)

    Rasch, Vibeke; Massawe, Siriel; McHomvu, Yasinta

    2004-01-01

    OBJECTIVE: To identify women having unsafe abortions and elucidate whether an acceptable follow-up rate among these women can be retrieved. STUDY POPULATION: One thousand three hundred and fifty-seven women attended Temeke Municipal Hospital, Dar es Salaam with an abortion-related diagnosis. METH...

  10. Lubricant use and condom use during anal sex in men who have sex with men in Tanzania

    NARCIS (Netherlands)

    Romijnders, Kim Agj; Nyoni, Joyce E; Ross, Michael W; McCurdy, Sheryl A; Mbwambo, Jessie; Kok, Gerjo; Crutzen, Rik

    2015-01-01

    The lack of data on condom and lubricant use among African men who have sex with men hinders prevention efforts. We describe use, knowledge, and access to lubricants in Dar es Salaam and Tanga, Tanzania. Data were collected in 2012 and 2013 from a cross-sectional survey of 200 men who have sex with

  11. "Finding a Life" among Undocumented Congolese Refugee Children in Tanzania

    Science.gov (United States)

    Mann, Gillian

    2010-01-01

    The majority of undocumented Congolese refugee children living in Dar es Salaam, Tanzania, experience extreme poverty and social exclusion, harassment and discrimination. Their fear of deportation, forcible removal to refugee camps and imprisonment is coupled with a strong feeling that they are unwelcome in Tanzania. These realities require that…

  12. Instructor Support Services: An Inevitable Critical Success Factor in Blended Learning in Higher Education in Tanzania

    Science.gov (United States)

    Raphael, Christina; Mtebe, Joel S.

    2016-01-01

    The adoption of blended learning to widen access, reduce cost, and improve the quality of education is becoming prevalent in higher education in sub-Saharan Africa and Tanzania in particular. University of Dar es Salaam and the Open University of Tanzania offer various blended learning courses using Moodle system via regional centres scattered…

  13. Perceptions of Child Sexual Abuse--A Qualitative Interview Study with Representatives of the Socio-Legal System in Urban Tanzania

    Science.gov (United States)

    Kisanga, Felix; Mbwambo, Jessie; Hogan, Norah; Nystrom, Lennarth; Emmelin, Maria; Lindmark, Gunilla

    2010-01-01

    Through in-depth interviews, this study explored perceptions and experiences of key players handling child sexual offense cases in Dar es Salaam, Tanzania. The informants included public police investigators, magistrates, legal workers, and social workers working with nongovernmental organizations. The interviews were recorded, transcribed…

  14. Language in Education in Eastern Africa.

    Science.gov (United States)

    Gorman, T. P., Ed.

    This volume contains the papers given at the first Eastern Africa Conference on Language and Linguistics, held in Dar es Salaam in December 1968, under the auspices of the Survey of Language Use and Language Teaching in Eastern Africa. The chief aim of the Conference was to bring together scholars and teachers working in Eastern Africa interested…

  15. Demonstration of anaerobic stabilization of black water in accumulation systems under tropical conditions

    NARCIS (Netherlands)

    Chaggu, E.J.; Sanders, W.; Lettinga, G.

    2007-01-01

    The anaerobic digestion of "human waste" was studied at Mlalakuwa residential settlement in Dar-es-Salaam, Tanzania at ambient tropical temperatures (24-31 degrees C). This settlement experiences a high water table with flooding during the rainy season, resulting in a very costly emptying of the lat

  16. CREATING OPPORTUNITIES IN AFRICA

    Institute of Scientific and Technical Information of China (English)

    DING YING

    2011-01-01

    Driving from the Johannesburg International Airport in South Africa to the city's downtown area,you can find almost every world-famous company.In Dar es Salaam,Tanzania,huge billboards of foreign companies dot the landscape of the coastal city.

  17. Brave New Mobile World

    Institute of Scientific and Technical Information of China (English)

    Maya Reid

    2011-01-01

    APPS are taking East Africa by storm.As mobile phone penetration rates increase,technologisis and software developers in the provide bigger and better services for an evergrowing consumer base.At the center of this flurry of activity is Nairobi,Kenya.But Dar Es Salaam in Tanzania and Uganda's Kampala may not be far behind.

  18. 2011 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Kittitas-Colockum Study Area

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WSI) collected Light Detection and Ranging (LiDAR) data on 6 days between September 15th and November 5th, 2010 for the Puget Sound LiDAR...

  19. TENSOR MODELING BASED FOR AIRBORNE LiDAR DATA CLASSIFICATION

    Directory of Open Access Journals (Sweden)

    N. Li

    2016-06-01

    Full Text Available Feature selection and description is a key factor in classification of Earth observation data. In this paper a classification method based on tensor decomposition is proposed. First, multiple features are extracted from raw LiDAR point cloud, and raster LiDAR images are derived by accumulating features or the “raw” data attributes. Then, the feature rasters of LiDAR data are stored as a tensor, and tensor decomposition is used to select component features. This tensor representation could keep the initial spatial structure and insure the consideration of the neighborhood. Based on a small number of component features a k nearest neighborhood classification is applied.

  20. DAR Assisted Layer-by-Layer Assembly of Aromatic Compounds

    Institute of Scientific and Technical Information of China (English)

    姜思光; 陈晓东; 张莉; 刘鸣华

    2003-01-01

    A facile DAR (diphenylamine-4-diazonium-formaldehyde resin)assisted layer-by-layer (LbL) assembly of uitrathin organic film of aromatic compounds has been investigated. The muitilayer of pyrene or anthracene was fabricated through simple dipping of the glass slide into the mixed solution of DAR with the target compounds. In this method, DAR acted as an assistant compound to help the assembling of the aromatic compounds. Such a convenient deposition method not only reserves the advantages of the traditional LbL technique but also simplifies the technique and extends the effectiveness of LbL technique to small molecules without any charge.

  1. Georeferenced LiDAR 3D Vine Plantation Map Generation

    OpenAIRE

    Meritxell Queraltó; Jordi Llop; Emilio Gil; Jordi Llorens

    2011-01-01

    The use of electronic devices for canopy characterization has recently been widely discussed. Among such devices, LiDAR sensors appear to be the most accurate and precise. Information obtained with LiDAR sensors during reading while driving a tractor along a crop row can be managed and transformed into canopy density maps by evaluating the frequency of LiDAR returns. This paper describes a proposed methodology to obtain a georeferenced canopy map by combining the information obtained with LiD...

  2. Tensor Modeling Based for Airborne LiDAR Data Classification

    Science.gov (United States)

    Li, N.; Liu, C.; Pfeifer, N.; Yin, J. F.; Liao, Z. Y.; Zhou, Y.

    2016-06-01

    Feature selection and description is a key factor in classification of Earth observation data. In this paper a classification method based on tensor decomposition is proposed. First, multiple features are extracted from raw LiDAR point cloud, and raster LiDAR images are derived by accumulating features or the "raw" data attributes. Then, the feature rasters of LiDAR data are stored as a tensor, and tensor decomposition is used to select component features. This tensor representation could keep the initial spatial structure and insure the consideration of the neighborhood. Based on a small number of component features a k nearest neighborhood classification is applied.

  3. LiDAR error estimation with WAsP engineering

    DEFF Research Database (Denmark)

    Bingöl, Ferhat; Mann, Jakob; Foussekis, D.

    2008-01-01

    The LiDAR measurements, vertical wind profile in any height between 10 to 150m, are based on assumption that the measured wind is a product of a homogenous wind. In reality there are many factors affecting the wind on each measurement point which the terrain plays the main role. To model LiDAR...... measurements and predict possible error in different wind directions for a certain terrain we have analyzed two experiment data sets from Greece. In both sites LiDAR and met. mast data have been collected and the same conditions are simulated with Riso/DTU software, WAsP Engineering 2.0. Finally measurement...

  4. COSIMA-ES-PORT

    DEFF Research Database (Denmark)

    Barfod, Michael Bruhn; Leleur, Steen

    2007-01-01

    and a multimodal terminal. The three studies indicates that a new road connection to the Port of Esbjerg is a very profitable project due to large travel time savings, whereas a new railway connection is not economically viable. However, a new multimodal terminal is also a very profitable project. The COSIMA-ES-PORT......This article describes the results of the research project – WP3 East-west, Interreg IIIB – concerning the de¬velop¬ment of a new composite decision model, COSIMA-ES-PORT, for the assessment of three pre-feasibility studies situated at the Port of Esbjerg: a road project, a railway project...... of COSIMA-ES-PORT showed some promising perspectives with regard to the implementation of other means of transportation for composite decision model assessment....

  5. NADAR ES LA CLAVE

    Directory of Open Access Journals (Sweden)

    MANUEL RUIZ C.

    2015-03-01

    Full Text Available Claro, la clave es nadar, nadar para crecer y trascender.  Pues, es el agua, el fluido mágico en el cual se dinamiza  nuestro cuerpo en forma sensorial, y en donde el espíritu  se recrea, mientras la mente se complace al comprender,  que es la natación, la que compromete al ser en su totalidad  y lo funde en una perfecta unidad funcional;  cuerpo y mente, soma y psiquis, sensaciones y sentimientos.

  6. Automatic registration method for mobile LiDAR data

    Science.gov (United States)

    Wang, Ruisheng; Ferrie, Frank P.

    2015-01-01

    We present an automatic mutual information (MI) registration method for mobile LiDAR and panoramas collected from a driving vehicle. The suitability of MI for registration of aerial LiDAR and aerial oblique images has been demonstrated under an assumption that minimization of joint entropy (JE) is a sufficient approximation of maximization of MI. We show that this assumption is invalid for the ground-level data. The entropy of a LiDAR image cannot be regarded as approximately constant for small perturbations. Instead of minimizing the JE, we directly maximize MI to estimate corrections of camera poses. Our method automatically registers mobile LiDAR with spherical panoramas over an approximate 4-km drive, and is the first example we are aware of that tests MI registration in a large-scale context.

  7. Elevation - LiDAR Survey Minnehaha Creek, MN Watershed

    Data.gov (United States)

    Army Corps of Engineers, Department of the Army, Department of Defense — LiDAR Bare-Earth Grid - Minnehaha Creek Watershed District. The Minnehaha Creek watershed is located primarily in Hennepin County, Minnesota. The watershed covers...

  8. LiDAR (Terrain), THURSTON COUNTY, WASHINGTON, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Fugro EarthData Company furnished the collection, processing, and development of LiDAR for 825 square miles in Washington (805 square miles of Thurston County and 20...

  9. 2009 PSLC-USGS Topographic LiDAR: Wenatchee

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WS) collected Light Detection and Ranging (LiDAR) data of the Wenatchee USGS area of interest (AOI) east of Wenatchee, WA on May 1nd ? May...

  10. 2009 PSLC-USGS Topographic LiDAR: Wenatchee

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WS) collected Light Detection and Ranging (LiDAR) data of the Wenatchee USGS area of interest (AOI) east of Wenatchee, WA on May 1nd - May...

  11. Shipborne LiDAR system for coastal change monitoring

    Science.gov (United States)

    Kim, chang hwan; Park, chang hong; Kim, hyun wook; hyuck Kim, won; Lee, myoung hoon; Park, hyeon yeong

    2016-04-01

    Coastal areas, used as human utilization areas like leisure space, medical care, ports and power plants, etc., are regions that are continuously changing and interconnected with oceans and land and the sea level has risen by about 8cm (1.9mm / yr) due to global warming from 1964 year to 2006 year in Korea. Coastal erosion due to sea-level rise has caused the problem of marine ecosystems and loss of tourism resources, etc. Regular monitoring of coastal erosion is essential at key locations with such volatility. But the survey method of land mobile LiDAR (light detection and ranging) system has much time consuming and many restrictions. For effective monitoring beach erosion, KIOST (Korea Institute of Ocean Science & Technology) has constructed a shipborne mobile LiDAR system. The shipborne mobile LiDAR system comprised a land mobile LiDAR (RIEGL LMS-420i), an INS (inertial navigation system, MAGUS Inertial+), a RTKGPS (LEICA GS15 GS25), and a fixed platform. The shipborne mobile LiDAR system is much more effective than a land mobile LiDAR system in the measuring of fore shore areas without shadow zone. Because the vessel with the shipborne mobile LiDAR system is continuously moved along the shoreline, it is possible to efficiently survey a large area in a relatively short time. Effective monitoring of the changes using the constructed shipborne mobile LiDAR system for seriously eroded coastal areas will be able to contribute to coastal erosion management and response.

  12. Es imposible no comunicar

    Directory of Open Access Journals (Sweden)

    Joan Costa y Solá-Segalés

    2012-04-01

    Full Text Available La confusión entre "comunicar" y "significar" proviene del hecho de que la comunicación transporta significados, pero también se producen significados fuera del proceso de comunicación. Es lo que llamamos "semiosis no comunicativa".

  13. Georeferenced LiDAR 3D vine plantation map generation.

    Science.gov (United States)

    Llorens, Jordi; Gil, Emilio; Llop, Jordi; Queraltó, Meritxell

    2011-01-01

    The use of electronic devices for canopy characterization has recently been widely discussed. Among such devices, LiDAR sensors appear to be the most accurate and precise. Information obtained with LiDAR sensors during reading while driving a tractor along a crop row can be managed and transformed into canopy density maps by evaluating the frequency of LiDAR returns. This paper describes a proposed methodology to obtain a georeferenced canopy map by combining the information obtained with LiDAR with that generated using a GPS receiver installed on top of a tractor. Data regarding the velocity of LiDAR measurements and UTM coordinates of each measured point on the canopy were obtained by applying the proposed transformation process. The process allows overlap of the canopy density map generated with the image of the intended measured area using Google Earth(®), providing accurate information about the canopy distribution and/or location of damage along the rows. This methodology was applied and tested on different vine varieties and crop stages in two important vine production areas in Spain. The results indicate that the georeferenced information obtained with LiDAR sensors appears to be an interesting tool with the potential to improve crop management processes.

  14. Georeferenced LiDAR 3D Vine Plantation Map Generation

    Directory of Open Access Journals (Sweden)

    Meritxell Queraltó

    2011-06-01

    Full Text Available The use of electronic devices for canopy characterization has recently been widely discussed. Among such devices, LiDAR sensors appear to be the most accurate and precise. Information obtained with LiDAR sensors during reading while driving a tractor along a crop row can be managed and transformed into canopy density maps by evaluating the frequency of LiDAR returns. This paper describes a proposed methodology to obtain a georeferenced canopy map by combining the information obtained with LiDAR with that generated using a GPS receiver installed on top of a tractor. Data regarding the velocity of LiDAR measurements and UTM coordinates of each measured point on the canopy were obtained by applying the proposed transformation process. The process allows overlap of the canopy density map generated with the image of the intended measured area using Google Earth®, providing accurate information about the canopy distribution and/or location of damage along the rows. This methodology was applied and tested on different vine varieties and crop stages in two important vine production areas in Spain. The results indicate that the georeferenced information obtained with LiDAR sensors appears to be an interesting tool with the potential to improve crop management processes.

  15. Whitman y Poe en la poesía de Rubén Darío

    Directory of Open Access Journals (Sweden)

    Humberto de Castro

    1967-01-01

    Full Text Available Una observación retrospectiva permite intentar la interpretación aproximada de lo que representaron - en conjunto- algunos hombres del siglo anterior, en distintos países, en cuanto a la búsqueda y el hallazgo de nuevas formas de expresión poética. Por ese camino sería posible plantear con cierta responsabilidad una cuestión que no es frecuente dilucidar en nuestro ambiente: ¿En qué medida se ejerció una influencia directa por parte de Whitman en la obra de Rubén Darío, y en qué medida, directa o indirectamente, hubo influencia de Poe en la creación artística de Darío?

  16. 2007 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Eastern Washington and River Corridors

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WS) collected Light Detection and Ranging (LiDAR) data in eastern Washington, eastern Oregon, and southern Canada in October and November,...

  17. 2002 Puget Sound LiDAR Consortium (PSLC) Unclassified Topographic LiDAR: Puget Sound Lowlands Washington

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TerraPoint surveyed and created this data for the Puget Sound LiDAR Consortium under contract. The area surveyed is approximately 730 square miles and covers the...

  18. 2012 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Chehalis River Watershed Area, Washington

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WSI) collected Light Detection and Ranging (LiDAR) data for the Chehalis River Watershed study area on January 28th, February 2nd-7th,...

  19. 2006 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Eastern Washington and River Corridors

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WS) collected Light Detection and Ranging (LiDAR) data in eastern Washington, eastern Oregon, and southern Canada in October and November,...

  20. Agrotóxico: que nome dar?

    Directory of Open Access Journals (Sweden)

    Márcia Gomide

    2005-12-01

    Full Text Available Os trabalhadores, de um modo geral, estão sempre expostos a maiores ou menores intensidades de risco. Os agricultores, em particular, também estão expostos e de forma bastante estabelecida. Contudo, trabalhos têm mostrado que existe um código coletivo de proteção para lhes permitir dar continuidade às suas atividades, uma vez que, em sua maioria, os próprios donos do cultivo fazem parte do processo produtivo e, portanto, precisam garantir a sua safra aplicando os agrotóxicos. Este trabalho apresenta uma pesquisa desenvolvida com agricultores de dois municípios do sudeste do Piauí, utilizando uma abordagem qualitativa, com o intuito de compreender os mecanismos de proteção destes agricultores com a sua atividade. Os resultados apontaram para práticas defensivas tais como consumo de bebida alcoólica, a sublocação do serviço aos mais jovens e a existência de um certo grau de compreensão do risco à saúde com a utilização dos agrotóxicos. A partir daí, se discute a importância da denominação dada ao agrotóxico, como um fator de proteção que deveria ser mais valorizado para maximizar a proteção do agricultor, em vez de se manter a estratégia de aumento de informação e controle de EPI (Equipamento de Proteção Individual.

  1. 2012-2013 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Hoh River Watershed, Washington (Deliveries 1 and 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WSI) collected Light Detection and Ranging (LiDAR) data on the Hoh River watershed survey area for the Puget Sound LiDAR Consortium and...

  2. Visual-LiDAR Odometry Aided by Reduced IMU

    Directory of Open Access Journals (Sweden)

    Yashar Balazadegan Sarvrood

    2016-01-01

    Full Text Available This paper proposes a method for combining stereo visual odometry, Light Detection And Ranging (LiDAR odometry and reduced Inertial Measurement Unit (IMU including two horizontal accelerometers and one vertical gyro. The proposed method starts with stereo visual odometry to estimate six Degree of Freedom (DoF ego motion to register the point clouds from previous epoch to the current epoch. Then, Generalized Iterative Closest Point (GICP algorithm refines the motion estimation. Afterwards, forward velocity and Azimuth obtained by visual-LiDAR odometer are integrated with reduced IMU outputs in an Extended Kalman Filter (EKF to provide final navigation solution. In this paper, datasets from KITTI (Karlsruhe Institute of Technology and Toyota technological Institute were used to compare stereo visual odometry, integrated stereo visual odometry and reduced IMU, stereo visual-LiDAR odometry and integrated stereo visual-LiDAR odometry and reduced IMU. Integrated stereo visual-LiDAR odometry and reduced IMU outperforms other methods in urban areas with buildings around. Moreover, this method outperforms simulated Reduced Inertial Sensor System (RISS, which uses simulated wheel odometer and reduced IMU. KITTI datasets do not include wheel odometry data. Integrated RTK (Real Time Kinematic GPS (Global Positioning System and IMU was replaced by wheel odometer to simulate the response of RISS method. Visual Odometry (VO-LiDAR is not only more accurate than wheel odometer, but it also provides azimuth aiding to vertical gyro resulting in a more reliable and accurate system. To develop low-cost systems, it would be a good option to use two cameras plus reduced IMU. The cost of such a system will be reduced than using full tactical MEMS (Micro-Electro-Mechanical Sensor based IMUs because two cameras are cheaper than full tactical MEMS based IMUs. The results indicate that integrated stereo visual-LiDAR odometry and reduced IMU can achieve accuracy at the

  3. UAS TOPOGRAPHIC MAPPING WITH VELODYNE LiDAR SENSOR

    Directory of Open Access Journals (Sweden)

    G. Jozkow

    2016-06-01

    Full Text Available Unmanned Aerial System (UAS technology is nowadays willingly used in small area topographic mapping due to low costs and good quality of derived products. Since cameras typically used with UAS have some limitations, e.g. cannot penetrate the vegetation, LiDAR sensors are increasingly getting attention in UAS mapping. Sensor developments reached the point when their costs and size suit the UAS platform, though, LiDAR UAS is still an emerging technology. One issue related to using LiDAR sensors on UAS is the limited performance of the navigation sensors used on UAS platforms. Therefore, various hardware and software solutions are investigated to increase the quality of UAS LiDAR point clouds. This work analyses several aspects of the UAS LiDAR point cloud generation performance based on UAS flights conducted with the Velodyne laser scanner and cameras. The attention was primarily paid to the trajectory reconstruction performance that is essential for accurate point cloud georeferencing. Since the navigation sensors, especially Inertial Measurement Units (IMUs, may not be of sufficient performance, the estimated camera poses could allow to increase the robustness of the estimated trajectory, and subsequently, the accuracy of the point cloud. The accuracy of the final UAS LiDAR point cloud was evaluated on the basis of the generated DSM, including comparison with point clouds obtained from dense image matching. The results showed the need for more investigation on MEMS IMU sensors used for UAS trajectory reconstruction. The accuracy of the UAS LiDAR point cloud, though lower than for point cloud obtained from images, may be still sufficient for certain mapping applications where the optical imagery is not useful.

  4. Uas Topographic Mapping with Velodyne LiDAR Sensor

    Science.gov (United States)

    Jozkow, G.; Toth, C.; Grejner-Brzezinska, D.

    2016-06-01

    Unmanned Aerial System (UAS) technology is nowadays willingly used in small area topographic mapping due to low costs and good quality of derived products. Since cameras typically used with UAS have some limitations, e.g. cannot penetrate the vegetation, LiDAR sensors are increasingly getting attention in UAS mapping. Sensor developments reached the point when their costs and size suit the UAS platform, though, LiDAR UAS is still an emerging technology. One issue related to using LiDAR sensors on UAS is the limited performance of the navigation sensors used on UAS platforms. Therefore, various hardware and software solutions are investigated to increase the quality of UAS LiDAR point clouds. This work analyses several aspects of the UAS LiDAR point cloud generation performance based on UAS flights conducted with the Velodyne laser scanner and cameras. The attention was primarily paid to the trajectory reconstruction performance that is essential for accurate point cloud georeferencing. Since the navigation sensors, especially Inertial Measurement Units (IMUs), may not be of sufficient performance, the estimated camera poses could allow to increase the robustness of the estimated trajectory, and subsequently, the accuracy of the point cloud. The accuracy of the final UAS LiDAR point cloud was evaluated on the basis of the generated DSM, including comparison with point clouds obtained from dense image matching. The results showed the need for more investigation on MEMS IMU sensors used for UAS trajectory reconstruction. The accuracy of the UAS LiDAR point cloud, though lower than for point cloud obtained from images, may be still sufficient for certain mapping applications where the optical imagery is not useful.

  5. Forest Road Detection Using LiDAR Data

    Institute of Scientific and Technical Information of China (English)

    Zahra Azizi; Akbar Najafi; Saeed Sadeghian

    2014-01-01

    We developed a three-step classification approach for forest road extraction utilizing LiDAR data. The first step employed the IDW method to interpolate LiDAR point data (first and last pulses) to achieve DSM, DTM and DNTM layers (at 1 m resolution). For this interpolation RMSE was 0.19 m. In the second step, the Support Vector Machine (SVM) was employed to classify the LiDAR data into two classes, road and non-road. For this classification, SVM indicated the merged distance layer with intensity data and yielded better identification of the road position. Assessments of the obtained results showed 63% correctness, 75% completeness and 52% quality of classification. In the next step, road edges were defined in the LiDAR-extracted layers, enabling accu-rate digitizing of the centerline location. More than 95% of the Li-DAR-derived road was digitized within 1.3 m to the field surveyed nor-mal. The proposed approach can provide thorough and accurate road inventory data to support forest management.

  6. A Study on Factors Affecting Airborne LiDAR Penetration

    Directory of Open Access Journals (Sweden)

    Wei-Chen Hsu

    2015-01-01

    Full Text Available This study uses data from different periods, areas and parameters of airborne LiDAR (light detection and ranging surveys to understand the factors that influence airborne LiDAR penetration rate. A discussion is presented on the relationships between these factors and LiDAR penetration rate. The results show that the flight height above ground level (AGL does not have any relationship with the penetration rate. There are some factors that should have larger influence. For example, the laser is affected by a wet ground surface by reducing the number of return echoes. The field of view (FOV has a slightly negative correlation with the penetration rate, which indicates that the laser incidence angle close to zero should achieve the best penetration. The vegetation cover rate also shows a negative correlation with the penetration rate, thus bare ground and reduced vegetation in the aftermath of a typhoon also cause high penetration rate. More return echoes could be extracted from the full-waveform system, thereby effectively improving the penetration rate. This study shows that full-waveform LiDAR is an effective method for increasing the number of surface reflected echoes. This study suggests avoiding LiDAR survey employment directly following precipitation to prevent laser echo reduction.

  7. Mathematical modelling applied to LiDAR data

    Directory of Open Access Journals (Sweden)

    Javier Estornell

    2013-06-01

    Full Text Available The aim of this article is to explain the application of several mathematic calculations to LiDAR (Light Detection And Ranging data to estimate vegetation parameters and modelling the relief of a forest area in the town of Chiva (Valencia. To represent the surface that describes the topography of the area, firstly, morphological filters were applied iteratively to select LiDAR ground points. From these data, the Triangulated Irregular Network (TIN structure was applied to model the relief of the area. From LiDAR data the canopy height model (CHM was also calculated. This model allowed obtaining bare soil, shrub and tree vegetation mapping in the study area. In addition, biomass was estimated from measurements taken in the field in 39 circular plots of radius 0.5 m and the 95th percentile of the LiDAR height datanincluded in each plot. The results indicated a high relationship between the two variables (measurednbiomass and 95th percentile with a coeficient of determination (R2 of 0:73. These results reveal the importance of using mathematical modelling to obtain information of the vegetation and land relief from LiDAR data.

  8. Biomass Estimation for Individual Trees using Waveform LiDAR

    Science.gov (United States)

    Wang, K.; Kumar, P.; Dutta, D.

    2015-12-01

    Vegetation biomass information is important for many ecological models that include terrestrial vegetation in their simulations. Biomass has strong influences on carbon, water, and nutrient cycles. Traditionally biomass estimation requires intensive, and often destructive, field measurements. However, with advances in technology, airborne LiDAR has become a convenient tool for acquiring such information on a large scale. In this study, we use infrared full waveform LiDAR to estimate biomass information for individual trees in the Sangamon River basin in Illinois, USA. During this process, we also develop automated geolocation calibration algorithms for raw waveform LiDAR data. In the summer of 2014, discrete and waveform LiDAR data were collected over the Sangamon River basin. Field measurements commonly used in biomass equations such as diameter at breast height and total tree height were also taken for four sites across the basin. Using discrete LiDAR data, individual trees are delineated. For each tree, a voxelization methods is applied to all waveforms associated with the tree to result in a pseudo-waveform. By relating biomass extrapolated using field measurements from a training set of trees to waveform metrics for each corresponding tree, we are able to estimate biomass on an individual tree basis. The results can be especially useful as current models increase in resolution.

  9. Extraction of building by airborne LiDAR point cloud with support of ENVI LiDAR%ENVI LiDAR 支持下利用机载 LiDAR 点云提取建筑物

    Institute of Scientific and Technical Information of China (English)

    张杰; 贺清清; 王飞

    2016-01-01

    对机载激光雷达测量技术、ENVI LiDAR 软件、建筑物提取流程进行了介绍,以 ISPRS 第三委员会提供的机载激光雷达点云数据为基础,基于 ENVI LiDAR 5.1对实验区的建筑物进行了提取,并通过 ArcGIS 结合同地区影像对其质量进行评价,实验流程及结果有一定的参考意义。%Technology of Airborne LiDAR(Light Detection And Ranging),the ENVI LiDAR and the process of building extraction are intro-duced briefly in this paper. Then,based on the International Society for Photogrammetry and Remote Sensing(ISPRS)commission Ⅲ and ENVI LiDAR 5. 1,the buildings in testing area were extracted. The evaluation results of quality was learned by overlaying the buildings onto the image in same place through ArcGIS,and the process and results thereof have certain reference significance.

  10. Hablar no es ver

    OpenAIRE

    López, Martha

    2000-01-01

    Los atenienses para referirse a los espartanos los llamaban lacónicos; lacónico es una abreviatura de lacedemonio y designa la dificultad de estos pueblos para manejar la palabra como consecuencia de dura formación disciplinar y obligada en términos de oralidad. Los atenienses en cambio poseían el don de la palabra (me refiero a los varones, adultos y ciudadanos), y el manejo reputado de la elocuencia de que se preciaban los griegos, tenía que ver con el ejercicio de la escritura que acompaña...

  11. Buscar a los muertos entre los vivos: dar cuerpo a los desaparecidos de la dictadura argentina por el Derecho

    OpenAIRE

    Garibian, Sévane

    2013-01-01

    La política estatal de desapariciones forzadas en Argentina (política planificada y ejecutada durante la dictadura militar de 1976 a 1983) posee todavía, hoy día, un efecto impactante: en ausencia de los cuerpos de los desaparecidos, las familias buscan a los muertos entre los vivos. Para ellas se trata de dar cuerpo, por el Derecho, a las víctimas desaparecidas y situadas por ese acto fuera de la ley. Si “el colmo de la desaparición es su propia desaparición” (Jean-Louis Déotte), entonces re...

  12. Gobernar es educar

    Directory of Open Access Journals (Sweden)

    Oscar Arias Sánchez

    2001-06-01

    Full Text Available

    Resumen. La educación juega un papel fundamental en la reducción del enemigo más formidable de la paz, la democracia y el desarrollo humano: la pobreza. Es el instrumento catalizador de la participación constructiva en los procesos sociales y políticos de los sectores silenciados y marginados del desarrollo.

    La educación es particularmente importante en un mundo cada vez más globalizado, convirtiéndose en punto de partida y elemento clave para comprender el pluralismo de los estados y sus diferentes manifestaciones culturales, contribuyendo de esta manera, a la integración nacional y regional. La educación como responsabilidad de todos debe no solo fijarse como objetivo la capacitación y adiestramiento de las personas, sino también, educarlas, más con el ejemplo que con la prédica, en una serie de principios y valores.

    Concluye el autor puntualizando la importancia de que se asuma el hacer política como práctica pedagógica. El político debe ser un maestro capaz de generar conocimiento en sí mismo y en los pueblos y modelar en sus acciones los principios que defiende con sus palabras. Hacer política y gobernar es educar y educarse.

     

    Abstract. Education plays a critical role in the reduction of the most prominent enemy of peace, democracy, and human development: poverty. It is the catalyst of the constructive participation in the social and political processes of those groups traditionally silenced and excluded from development.

    Education is particularly important in a global society. It is a fundamental factor to understand the pluralism of the nations and their cultural diversity. It contributes to the national and regional integration. Education, viewed as everyone's responsibility, should not only be aimed at instructing and training individuals for the labor market, but also at educating them in a series of principles and values. In so doing

  13. Raster Vs. Point Cloud LiDAR Data Classification

    Science.gov (United States)

    El-Ashmawy, N.; Shaker, A.

    2014-09-01

    Airborne Laser Scanning systems with light detection and ranging (LiDAR) technology is one of the fast and accurate 3D point data acquisition techniques. Generating accurate digital terrain and/or surface models (DTM/DSM) is the main application of collecting LiDAR range data. Recently, LiDAR range and intensity data have been used for land cover classification applications. Data range and Intensity, (strength of the backscattered signals measured by the LiDAR systems), are affected by the flying height, the ground elevation, scanning angle and the physical characteristics of the objects surface. These effects may lead to uneven distribution of point cloud or some gaps that may affect the classification process. Researchers have investigated the conversion of LiDAR range point data to raster image for terrain modelling. Interpolation techniques have been used to achieve the best representation of surfaces, and to fill the gaps between the LiDAR footprints. Interpolation methods are also investigated to generate LiDAR range and intensity image data for land cover classification applications. In this paper, different approach has been followed to classifying the LiDAR data (range and intensity) for land cover mapping. The methodology relies on the classification of the point cloud data based on their range and intensity and then converted the classified points into raster image. The gaps in the data are filled based on the classes of the nearest neighbour. Land cover maps are produced using two approaches using: (a) the conventional raster image data based on point interpolation; and (b) the proposed point data classification. A study area covering an urban district in Burnaby, British Colombia, Canada, is selected to compare the results of the two approaches. Five different land cover classes can be distinguished in that area: buildings, roads and parking areas, trees, low vegetation (grass), and bare soil. The results show that an improvement of around 10 % in the

  14. Development of a wind turbine LiDAR simulator

    OpenAIRE

    Schlipf, David; Trujillo , Juan José; Basterra, Valeria; Kühn, Martin

    2009-01-01

    Remote sensing techniques like LiDAR offer many novel applications to the wind energy community, e.g. fast and accurate measurements of inflow and wake wind fields from the turbine nacelle. The prospects of such a new technique are evaluated with a software tool simulating a nacelle-based LiDAR system. The paper presents the implementation and application of a simulator that has been conceived to support the design of wind field scanning procedures. The tool helps to optimize the hardware set...

  15. Darüşşifas Where Music Threapy was Practiced During Anatolian Seljuks and Ottomans / Selçuklu ve Osmanlı Darüşşifalarında Müzikle Tedavi

    Directory of Open Access Journals (Sweden)

    Gülşen Erdal

    2013-03-01

    ncesinde Türklerde nasıl kullanıldığını vurgulamak amacıyla ele alınmıştır. Buradan hareketle Kayseri Gevher Nesibe Tıp Medresesi (1206, Divriği Ulu Camii ve Darüşşifası (1228, Amasya Darüşşifası (1309, Fatih Darüşşifası (1470 Edirne Sultan II.Bayezid Darüşşifası (1488, Süleymaniye Tıp Medresesi ve Şifahanesi (1556 Enderun Hastanesi bu çalışmada müzikle tedavinin yapıldığı kurumlar arasında öne çıkanlar olarak incelenmiştir. Böylece Türk müziği makamları ve hastalıklar arasında kurulan ilişkiler Selçuklu ve Osmanlı Sanatı içinde müzikle tedavinin gerekleri düşünülerek inşa edilen bu yapıların yaşam amaçları ve müziğin iyileştirici gücünün vurgulanması amaçlanmıştır. La musicothérapie pratiquée pendant le règne des Seldjoukides d’Anatolie et des Ottomans Résumé La musicothérapie, l’une des plus anciennes méthodes de traitement connues, remonte à des milliers d’années. La musicothérapie turque pratiquée dans les hôpitaux ottomans et seldjoukides utilisait l’acoustique appropriée au traitement des troubles mentaux avec la lecture des livres des savants comme Avicenne, Râzî, Fârabî, Hasan Shuurî et Gevrekzade Hasan Efendi. Ainsi la musicothérapie et l’amélioration de la musicothérapie de manière exemplaire à l’époque des Ottomans et Seldjoukides est la première pratique sérieuse de la musicothérapie. Darüşşifa est l’un des noms donnés aux établissements médicaux et éducatifs qui confèrent au peuple des services de santé en fonction de la pratique et de l’observation et qui traitent les patients dans le monde turc et islamique. Les Turcs ont commencé à reconstruire différents bâtiments selon leurs possibilités en Anatolie. Dans une courte période, ils ont construit plusieurs types de constructions tels que caravansérails, médersas, mosquées, darüşşifas. En seldjoukide et ottoman darüşşifas, les sujets médicaux ont été acquis d

  16. El Futuro es Hoy

    Directory of Open Access Journals (Sweden)

    Alfonso Latiff Conde

    2002-08-01

    Full Text Available

    En ninguna otra época de la historia como en la nuestra se ha producido una transición tan rápida hacia el futuro, en el campo de la medicina.

    Lo que había sido una centuria de evolución desde la era Industrial a la era de la Informática, en la pasada década se ha convertido en una revolución.

    La cirugía laparoscopica que ha constituído el despertar a la edad de la informática como la tecnología lider es considerada ahora un standard en la práctica médica. En la actualidad tecnologias más avanzadas prometen mayores progresos en la medicina.

    La mayor revolución médica ocurrió en la cirugía en las postrimerias del siglo diecinueve cuando algunos gigantes de la medicina todavía caminaban sobre la tierra. Estos visionarios comprendieron la magnitud del cambio y dieron nacimiento a la nueva disciplina de la cirugía. Entre ellos estaban Bilroth, Lister, Virchow y Morton.

    Nunca trabajaron juntos, pero la integración espontánea de sus investigaciones y sus habilidades clínicas hicieron posible la nueva cirugía. Fue la convergencia de sus visiones y sus tecnologias las que dieron un vuelco a la cirugía. Bilroth aportó nuevas técnicas y nuevos instrumentos Lister aportó la asepsia, Virchow la patología y Morton la anestesia.

    Los antiguos mitos y muchos hechos empiricos hicieron creer por miles de años en la inviolabilidad del cuerpo humano. Las herramientas científicas de la Era Industrial convirtieron en realidad lo imposible y la ciencia dio nacimiento a la moderna cirugía. En un corto periodo de tiempo se establecieron los fundamentos de una cirugía que permitiría a las siguientes generaciones liderar nuevos avances y tecnologias.

    Nada estremeció más los fundamentos de la medicina como esta explosión de la cirugía. Comprender el shock, la cirugía cardiaca y coronaria, los trasplantes, tuvieron un enorme impacto que conmocionó la medicina. Es obvio que los cambios producidos

  17. Combinando datos LiDAR e inventario forestal para identificar estados avanzados de desarrollo en bosques caducifolios

    Directory of Open Access Journals (Sweden)

    E. Palop-Navarro

    2016-01-01

    Full Text Available Los bosques viejos son particularmente escasos debido a la explotación histórica de los ecosistemas forestales. Su estructura – caracterizada por múltiples especies y edades de árboles, presencia de claros, y abundante madera muerta – es particularmente difícil de recuperar tras la homogeneización derivada de la explotación forestal. Además, de ella depende la conservación de especialistas forestales como insectos saproxílicos, pícidos, etc. Caracterizar e identificar esta estructura es por tanto importante en la conservación y restauración de este tipo de bosques y sus comunidades. La estructura y composición de los bosques ha sido recogida históricamente en los inventarios forestales. Éstos aportan información valiosa, si bien de naturaleza discreta, y pueden ser menos eficientes en zonas de difícil acceso. A este respecto, la tecnología LiDAR (Light Detection and Ranging aporta información tridimensional y continua de la estructura forestal, constituyendo una herramienta útil para complementar los trabajos de campo de los inventarios. En este estudio evaluamos la posibilidad de cuantificar estados sucesionales avanzados en bosques caducifolios del norte de la Península Ibérica a partir de datos LiDAR públicos (densidad 0.5 puntos m-2. Primero contrastamos las variables derivadas de los datos LiDAR con las derivadas del cuarto Inventario Forestal Nacional (IFN4, lo que mostró la existencia de correlaciones, sobre todo, en alturas máximas y medias, aunque el ajuste varía de forma considerable con el diámetro del inventario considerado. Posteriormente construimos modelos predictivos simples para la identificación de bosques viejos en parcelas del IFN4 (variable binaria Bosque Viejo. El modelo final lo conformaron las variables LiDAR Altura desvest y Altura media2 (indicadoras de estructuras heterogéneas y árboles de tamaños diversos en las etapas más avanzadas del desarrollo, junto con la dominancia de

  18. 2011 U.S. Geological Survey (USGS) Topographic LiDAR: Louisiana Region 2

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TASK NAME: Louisiana Region 2 LiDAR ARRA Task Order LiDAR Data Acquisition and Processing Production Task- Orleans, Plaquemines, St. Bernard, St. Tammany Parishes,...

  19. 2011 U.S. Geological Survey (USGS) Topographic LiDAR: Louisiana Region 1

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TASK NAME: Louisiana Region 1 LiDAR ARRA Task Order LiDAR Data Acquisition and Processing Production Task- Vermillion, Iberia, St. Mary, Terrebonne, and Lafourche...

  20. 2007 US Army Corps of Engineers (USACE), Jacksonville District US Virgin Islands LiDAR

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This Light Detection and Ranging (LiDAR) bare-earth classified LAS dataset is a topographic survey conducted for the USACE USVI LiDAR Project. These data were...

  1. 2004 Federal Emergency Management Agency (FEMA) Bare Earth Topographic LiDAR: Connecticut River

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — LiDAR data is remotely sensed high-resolution elevation data collected by an airborne collection platform. The LiDAR files were converted from .PTS format to LAS...

  2. 2011 USGS Topographic LiDAR: Suwannee River Expansion

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — USGS Task Order No. G10PD00236 USGS Contract No. G10PC00093 The Light Detection and Ranging (LiDAR) dataset is a survey of the Suwannee River Expansion in...

  3. Effective LiDAR Damage Detection: Comparing Two Detection Algorithms

    Institute of Scientific and Technical Information of China (English)

    BIAN Haitao; BAI Libin; WANG Xiaoyu; LIU Wangiu; CHEN Shenen; WANG Shengguo

    2011-01-01

    The health conditions of highway bridges is critical for sustained transportation operations. US federal government mandates that all bridges built with public funds are to be inspected visually every two years.There is a growing consensus that additional rapid and non-intrusive methods for bridge damage evaluation are needed. This paper explores the potential of applying ground-based laser scanners for bridge damage evaluation. LiDAR has the potential of providing high-density, full-field surface static imaging. Hence, it can generate volumetric quantification of concrete corrosion or steel erosion. By recording object surface topology, LiDAR can detect different damages on the bridge structure and differentiate damage types according to the surface flatness and smoothness. To determine the effectiveness of LiDAR damage detection, two damage detection algorithms are presented and compared using scans on actual bridge damages. The results demonstrate and validate LiDAR damage quantification, which can be a powerful tool for bridge condition evaluation.

  4. Modeling low-height vegetation with airborne LiDAR

    Science.gov (United States)

    Low-height vegetation, common in semiarid regions, is difficult to characterize with LiDAR (Light Detection and Ranging) due to similarities, in time and space, of the point returns of vegetation and ground. Other complications may occur due to the low-height vegetation structural characteristics a...

  5. Tree filtering for high density airborne LiDAR data

    NARCIS (Netherlands)

    Abd Rahman, M.Z.; Gorte, B.G.H.

    2008-01-01

    A high resolution Airborne LiDAR data creates better opportunity for an individual tree measurement and provides valuable results for more precise forest inventory. This paper presents tree filtering approach that able to separate dominant tree and undergrowth vegetation. The results can be used for

  6. ¿Qué es una Teoría Gauge?

    OpenAIRE

    Sánchez‐Tejerina San José, Luis

    2014-01-01

    El objetivo de este trabajo es dar una idea de la base de las teorías gauge a partir de una visión histórica de su aparición. Primero haremos un breve repaso a la historia del electromagnetismo, ya que es en esta teoría donde primero va a aparecer el concepto de invarianza gauge. En el siguiente apartado presentaremos las dificultades que plantea la no univocidad de los potenciales en mecánica cuántica, y también como se solucionan, introduciendo el concepto de acoplamiento mínimo y la deriva...

  7. Development and assessment of DArT markers in triticale.

    Science.gov (United States)

    Badea, A; Eudes, F; Salmon, D; Tuvesson, S; Vrolijk, A; Larsson, C-T; Caig, V; Huttner, E; Kilian, A; Laroche, André

    2011-05-01

    Triticale (X Triticosecale Wittm.) is a hybrid derived by crossing wheat (Triticum sp.) and rye (Secale sp.). Till date, only a limited number of simple sequence repeat (SSRs) markers have been used in triticale molecular analyses and there is a need to identify dedicated high-throughput molecular markers to better exploit this crop. The objective of this study was to develop and evaluate diversity arrays technology (DArT) markers in triticale. DArT marker technology offers a high level of multiplexing. Development of new markers from triticale accessions was combined with mining the large collection of previously developed markers in rye and wheat. Three genotyping arrays were used to analyze a collection of 144 triticale accessions. The polymorphism level ranged from 8.6 to 23.8% for wheat and rye DArT markers, respectively. Among the polymorphic markers, rye markers were the most abundant (3,109) followed by wheat (2,214) and triticale (719). The mean polymorphism information content values were 0.34 for rye DArT markers and 0.37 for those from triticale and wheat. High correlation was observed between similarity matrices derived from rye, triticale, wheat and combined marker sets, as well as for the cophenetic values matrices. Cluster analysis revealed genetic relationships among the accessions consistent with the agronomic and pedigree information available. The newly developed triticale DArT markers as well as those originated from rye and wheat provide high quality markers that can be used for diversity analyses and might be exploited in a range of molecular breeding and genomics applications in triticale.

  8. 47 CFR 25.401 - Satellite DARS applications subject to competitive bidding.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Satellite DARS applications subject to...) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Competitive Bidding Procedures for DARS § 25.401 Satellite DARS applications subject to competitive bidding. Mutually exclusive initial applications for...

  9. 2011 U.S. Geological Survey Topographic LiDAR: LiDAR for the North East

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — USGS Contract: G10PC00026, Task Order Number: G10PD02143 Task Order Numbers: G10PD01027 (ARRA) and G10PD02143 (non-ARRA) The LiDAR for the North East Project, funded...

  10. 2012 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Jefferson and Clallam Counties, Washington

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WSI) collected Light Detection and Ranging (LiDAR) data for the Jefferson/Clallam study area on March 23rd-25th, April 13th-15th, and May...

  11. 2005 Mississippi Merged LiDAR Data (2005 LiDAR data merged with 2005 Post-Katrina LiDAR data to create a bare-earth product for flood plain mapping in coastal Mississippi).

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Pre- and post-hurricane Katrina LiDAR datasets of Hancock, Harrison, and Jackson Counties, MS, were merged into a seamless coverage by URS. The pre-Katrina LiDAR...

  12. Road Curb Extraction From Mobile LiDAR Point Clouds

    Science.gov (United States)

    Xu, Sheng; Wang, Ruisheng; Zheng, Han

    2017-02-01

    Automatic extraction of road curbs from uneven, unorganized, noisy and massive 3D point clouds is a challenging task. Existing methods often project 3D point clouds onto 2D planes to extract curbs. However, the projection causes loss of 3D information which degrades the performance of the detection. This paper presents a robust, accurate and efficient method to extract road curbs from 3D mobile LiDAR point clouds. Our method consists of two steps: 1) extracting the candidate points of curbs based on the proposed novel energy function and 2) refining the candidate points using the proposed least cost path model. We evaluated our method on a large-scale of residential area (16.7GB, 300 million points) and an urban area (1.07GB, 20 million points) mobile LiDAR point clouds. Results indicate that the proposed method is superior to the state-of-the-art methods in terms of robustness, accuracy and efficiency. The proposed curb extraction method achieved a completeness of 78.62% and a correctness of 83.29%. These experiments demonstrate that the proposed method is a promising solution to extract road curbs from mobile LiDAR point clouds.

  13. Rockfall hazard analysis using LiDAR and spatial modeling

    Science.gov (United States)

    Lan, Hengxing; Martin, C. Derek; Zhou, Chenghu; Lim, Chang Ho

    2010-05-01

    Rockfalls have been significant geohazards along the Canadian Class 1 Railways (CN Rail and CP Rail) since their construction in the late 1800s. These rockfalls cause damage to infrastructure, interruption of business, and environmental impacts, and their occurrence varies both spatially and temporally. The proactive management of these rockfall hazards requires enabling technologies. This paper discusses a hazard assessment strategy for rockfalls along a section of a Canadian railway using LiDAR and spatial modeling. LiDAR provides accurate topographical information of the source area of rockfalls and along their paths. Spatial modeling was conducted using Rockfall Analyst, a three dimensional extension to GIS, to determine the characteristics of the rockfalls in terms of travel distance, velocity and energy. Historical rockfall records were used to calibrate the physical characteristics of the rockfall processes. The results based on a high-resolution digital elevation model from a LiDAR dataset were compared with those based on a coarse digital elevation model. A comprehensive methodology for rockfall hazard assessment is proposed which takes into account the characteristics of source areas, the physical processes of rockfalls and the spatial attribution of their frequency and energy.

  14. Preliminary application and evaluation of loop-mediated isothermal amplification (LAMP for detection of bovine theileriosis and trypanosomosis in Tanzania : research communication

    Directory of Open Access Journals (Sweden)

    O.M.M. Thekisoe

    2007-09-01

    Full Text Available The sensitivity of LAMP, PCR and microscopy to detect Theileria spp. and Trypanosoma congolense in field-derived bovine blood samples from Tanzania was evaluated and compared. No parasites were detected by microscopy. Furthermore, no bovine Theileria spp. were detected by LAMP and PCR from all the 24 samples collected from Arusha. Four and one out of 24 samples were positive for Theileria congolense infection by LAMP and PCR respectively while, 18 and nine out of 40 samples from Dar es Salaam were positive by LAMP and PCR for Theileria spp. Infection, respectively. Although all samples from Dar es Salaam were negative for Trypanosoma congolense infections by PCR, 12 out of 40 samples were LAMP positive. Whilst PCR is an established gene amplification method for the detection of Theileria and trypanosome parasites, this study introduces LAMP as an alternative molecular diagnostic tool that could be used in large-scale epidemiological surveys.

  15. Access to HIV prevention services among gender based violence survivors in Tanzania

    OpenAIRE

    Mboya, Beati; Temu, Florence; Awadhi, Bayoum; Ngware, Zubeda; Ndyetabura, Elly; Kiondo, Gloria; Maridadi, Janneth

    2012-01-01

    Introduction Currently, Tanzania's HIV prevalence is 5.7%. Gender inequality and Gender Based Violence (GBV) are among factors fuelling the spread of HIV in Tanzania. This study was conducted to assess universal access to HIV prevention services among GBV survivors in Iringa and Dar-es-Salaam where HIV prevalence is as high as 14.7% and 9% respectively compared to a national average of 5.7%. Methods In 2010, a mixed methods study using triangulation model was conducted in Iringa and Dar-es-Sa...

  16. es

    Directory of Open Access Journals (Sweden)

    Esther Bernal Valls

    Full Text Available El uso de ejercicios en el tratamiento de pacientes con déficit vestibular crónico está incrementándose de forma notable, lo que evidencia que se trata de un procedimiento que resulta beneficioso para este tipo de pacientes. Los buenos resultados que se obtienen sugieren que los ejercicios vestibulares dan lugar a una estabilidad postural y a una disminución de la sensación de desequilibrio.

  17. Multipath Estimation in Urban Environments from Joint GNSS Receivers and LiDAR Sensors

    OpenAIRE

    Fernández, Antonio J.; Fabio Dovis; David De Castro; Xin Chen; Khurram Ali

    2012-01-01

    In this paper, multipath error on Global Navigation Satellite System (GNSS) signals in urban environments is characterized with the help of Light Detection and Ranging (LiDAR) measurements. For this purpose, LiDAR equipment and Global Positioning System (GPS) receiver implementing a multipath estimating architecture were used to collect data in an urban environment. This paper demonstrates how GPS and LiDAR measurements can be jointly used to model the environment and obtain robust receivers....

  18. GEOBIA methods for LiDAR obtained point clouds

    OpenAIRE

    Tomljenović, Ivan

    2012-01-01

    This paper critically analyses the state of the art provided in today’s scientific »market of knowledge« concerning the subject of object delineation from LiDAR obtained 3D point clouds. Such approach became a very popular subject in many scientific fields (forestry, geography, archaeology, etc.). The author will give multiple examples on how other authors deal with object extraction and delineation from 3D point clouds. He will also give a brief introduction and explanation of terms such as ...

  19. Psychological effects of business trainings in Tanzania

    OpenAIRE

    Łyniewska, Agnieszka Anna; Selezneva, Olga

    2009-01-01

    This master thesis, as a part of a project on business trainings in Tanzania, investigates the effects of these trainings on change in mindset and soft skills of microentrepreneurs in Dar es Salaam. It focuses on following dimensions: Creativity, Individualism, Locus of Control, Need for Achievement, Dispositional Optimism and Trust/Relationship. The significant differences are found on the number of dimensions. Entrepreneurs who took part in the training have more internal loc...

  20. Brave New Mobile World

    Institute of Scientific and Technical Information of China (English)

    Maya; Reid

    2011-01-01

    An oral history of the mobile app boom in East Africa APPS are taking East Africa by storm.As mobile phone penetration rates increase,technologists and software developers in the region are scrambling to provide bigger and better services for an evergrowing consumer base. At the center of this flurry of activity is Nairobi,Kenya. But Dar Es Salaam in Tanzania and Uganda’s

  1. Social networks of men who have sex with men and their implications for HIV/STI interventions: results from a cross-sectional study using respondent-driven sampling in a large and a small city in Tanzania

    Science.gov (United States)

    Ross, Michael W; Larsson, Markus; Jacobson, Jerry; Nyoni, Joyce; Agardh, Anette

    2016-01-01

    Objective Men who have sex with men (MSM) in sub-Saharan Africa remain hidden and hard to reach for involvement in HIV and sexually transmitted infection (STI) services. The aim of the current study was to describe MSM social networks in a large and a small Tanzanian city in order to explore their utility for peer-based healthcare interventions. Methods Data were collected through respondent-driven sampling (RDS) in Dar es Salaam (n=197) and in Tanga (n=99) in 2012 and 2013, using 5 and 4 seeds, respectively. All results were adjusted for RDS sampling design. Results Mean personal network size based on the number of MSM who were reported by the participants, as known to them was 12.0±15.5 in Dar es Salaam and 7.6±8.1 in Tanga. Mean actual RDS network size was 39.4±31.4 in Dar es Salaam and 25.3±9.7 in Tanga. A majority (97%) reported that the person from whom they received the recruitment coupon was a sexual partner, close friend or acquaintance. Homophile in recruitment patterns (selective affiliation) was present for age, gay openness, and HIV status in Dar es Salaam, and for sexual identification in Tanga. Conclusions The personal network sizes and existence of contacts between recruiter and referral indicate that it is possible to use peer-driven interventions to reach MSM for HIV/STI interventions in larger and smaller sub-Saharan African cities. The study was reviewed and approved by the University of Texas Health Science Center's Institutional Review Board (HSC-SPH-10-0033) and the Tanzanian National Institute for Medical Research (NIMR/HQ/R.8a/Vol. IX/1088). PMID:27864245

  2. CREATING OPPORTUNITIES IN AFRICA

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Chinese enterprises generate jobs for Africans while exploring the vast potential of the continent Driving from the Johannesburg International Airport in South Africa to the city’s downtown area,you can find almost every world-famous company. In Dar es Salaam,Tanzania,huge billboards of foreign companies dot the landscape of the coastal city. With a population of 900 million and

  3. Data management based on geocoding index and adaptive visualization for airborne LiDAR

    Science.gov (United States)

    Zhi, Xiaodong

    2008-10-01

    With more surveying practice and deeper application, data post-process for airborne LiDAR system has been extracted lots of attention in data accuracy, post-process, fusion, modeling, automation and visualization. However, post-process and flexible visualization were found to be the bottle-neck which limits the LiDAR data usage for industrial applications. The cause of above bottle-neck problems is great capacity for LiDAR system. Thus in article a geocoding index based multivariate data management and adaptive visualization will be studied for based on the feature of airborne LiDAR's data to improve automatization of post-process and surveying efficiency.

  4. Weibull approximation of LiDAR waveforms for estimating the beam attenuation coefficient.

    Science.gov (United States)

    Montes-Hugo, Martin A; Vuorenkoski, Anni K; Dalgleish, Fraser R; Ouyang, Bing

    2016-10-03

    Tank experiments were performed at different water turbidities to examine relationships between the beam attenuation coefficient (c) and Weibull shape parameters derived from LiDAR waveforms measured with the Fine Structure Underwater LiDAR (FSUIL). Optical inversions were made at 532 nm, within a c range of 0.045-1.52 m-1, and based on a LiDAR system having two field-of-view (15 and 75.7 mrad) and two linear polarizations. Consistently, the Weibull scale parameter or P2 showed the strongest covariation with c and was a more accurate proxy with respect to the LiDAR attenuation coefficient.

  5. Es tiempo de cambiar el curso de la Historia

    Directory of Open Access Journals (Sweden)

    François Houtart

    2001-01-01

    Full Text Available La situación extrema de pobreza, marginalidad y todas las secuelas que derivan del actual orden histórico de la economía neoliberal globalizadora, es la principal característica que define a la sociedad moderna como injusta, a la vez que depredadora del hombre y de la naturaleza. Enfrentamos a una sociedad que no ha sabido, ni querido, dar respuesta a las necesidades básicas de sus ciudadanos ya que su principal interés continúa siendo la acumulación del capital y el desarrollo de la ideología del mercado total. Esta historia no puede continuar porque ha llegado a su fin, al crear las condiciones infrahumanas que están destruyendo paulatinamente las vidas de un alto porcentaje de seres humanos. Para cambiar el curso de la Historia, es necesario una conciencia crítica del colectivo humano reprimido contra el status quo.

  6. Applying the Moment Distance Framework to LiDAR Waveforms

    Science.gov (United States)

    Salas, E. L.; Aguilar-Amuchastegui, N.; Henebry, G. M.

    2010-12-01

    In the past decade or so, there have only been limited approaches formulated for the analysis of waveform LiDAR data. We illustrate how the Moment Distance (MD) framework can characterize the shape of the LiDAR waveforms using simple, computationally fast, geometric operations. We assess the relationship of the MD metrics to some key waveform landmarks - such as locations of peaks, power of returns, and pseudo-heights - using LVIS datasets acquired over a tropical forest in La Selva, Costa Rica in 1998 and 2005. We also apply the MD framework to 2003 LVIS data from Howland Forest, Maine. We also explore the effects of noise on the MD Index (MDI). Our results reveal that the MDI can capture important dynamics in canopy structure. Movement in the location of the peaks is detected by shifts in the MDI. Because this new approach responds to waveform shape, it is more sensitive to changes of location of peak returns than to the power of the return. Results also suggest a positive relationship between the MDI and the canopy pseudo-height.

  7. Performance testing of LiDAR exploitation software

    Science.gov (United States)

    Varela-González, M.; González-Jorge, H.; Riveiro, B.; Arias, P.

    2013-04-01

    Mobile LiDAR systems are being used widely in recent years for many applications in the field of geoscience. One of most important limitations of this technology is the large computational requirements involved in data processing. Several software solutions for data processing are available in the market, but users are often unknown about the methodologies to verify their performance accurately. In this work a methodology for LiDAR software performance testing is presented and six different suites are studied: QT Modeler, AutoCAD Civil 3D, Mars 7, Fledermaus, Carlson and TopoDOT (all of them in x64). Results depict as QTModeler, TopoDOT and AutoCAD Civil 3D allow the loading of large datasets, while Fledermaus, Mars7 and Carlson do not achieve these powerful performance. AutoCAD Civil 3D needs large loading time in comparison with the most powerful softwares such as QTModeler and TopoDOT. Carlson suite depicts the poorest results among all the softwares under study, where point clouds larger than 5 million points cannot be loaded and loading time is very large in comparison with the other suites even for the smaller datasets. AutoCAD Civil 3D, Carlson and TopoDOT show more threads than other softwares like QTModeler, Mars7 and Fledermaus.

  8. IsoDAR - A Definitive Search for Sterile Neutrinos

    Science.gov (United States)

    Barletta, William

    2013-04-01

    The steady development of high power cyclotrons, mostly in industry, is making possible a definitive, highly cost effective approach to the search for sterile neutrinos. In the proposed IsoDAR experiment a 600 kW beam of protons from a 60 MeV, H2+ cyclotron will impinge on a lithium target to generate copious Li-8. The Li-8 then decays at rest to yield a powerful source of anti-neutrinos that can be located ˜20 m from a hydrogenous detector. In particular our collaboration has been designing the accelerator / target system to be consistent with installation in the Kamioka mine to use the Kamland detector to record inverse beta decay events. We show that this source / detector combination can reveal or exclude the global-fit allowed region at 5 sigma in four months and differentiate between 1 and 2 sterile neutrinos with a few years of continued running. Our studies also show that high power cyclotrons will provide the most cost effective source for such an experiment. In addition, the 60 MeV IsoDAR cyclotron would be an ideal injector for DAEdALUS, our approach to measuring CP violation in the neutrino sector with decay-at-rest experiment.

  9. Dynamisch-optische Oberflächenvermessung des plantaren Fußes

    OpenAIRE

    Schmeltzpfenning, Timo

    2011-01-01

    Dynamisch-optische Oberflächenvermessung des plantaren Fußes Inhalt und Vorgehensweise Die Entwicklung eines zeitauflösenden dreidimensionalen Fußscanners unter Verwendung einer dynamisch-optischen Oberflächenvermessung stellt die primäre Zielsetzung dar. Dieses System wurde anschließend genutzt, um erste Erkenntnisse zur dynamischen Fußformveränderung über den Abrollvorgang zu gewinnen. Die Relevanz der Formveränderung, z.B. für die industrielle Schuhfertigung, wird in der Arbeit...

  10. Perfil de la Revista y Normas para las(os autoras(es

    Directory of Open Access Journals (Sweden)

    Andrea Lampis

    2015-10-01

    Full Text Available La Revista Colombiana de Sociología (rcs es una publicación científica semestral que, desde el 2 de diciembre de 1979, se ha consolidado como una de las publicaciones que más han contribuido a la difusión de las discusiones clásicas y contemporáneas de la sociología y se ha caracterizado por dar lugar a los trabajos de académicos reconocidos en la comunidad científica nacional e internacional, así como de estudiantes y egresados.

  11. 2001-2002 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Island County and Northeast Jefferson County, Washington

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TerraPoint surveyed and created this data for the Puget Sound LiDAR Consortium under contract. The area surveyed is approximately 525 square miles and covers all of...

  12. Colombia es una cosa penetrable

    Directory of Open Access Journals (Sweden)

    Gilberto Loaiza Cano

    2007-10-01

    Full Text Available Colombia es una cosa impenetrable. Raíces de la intolerancia y otros ensayos sobre historia política y vida intelectual. Juan Guillermo Gómez García. Bogotá, Diente de León, 2006, 454 pág.

  13. Wayne and Washtenaw Counties 1.0 PPSM LiDAR

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TASK NAME: Wayne and Washtenaw Counties 1.0 PPSM LiDAR LiDAR Data Acquisition and Processing Production Task USGS CONTRACT: 07CRCN0006 TASK ORDER NUMBER: G09PD00300...

  14. 2011-2013 Indiana Statewide Imagery and LiDAR Program: Lake Michigan Watershed Counties

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Indiana's Statewide LiDAR data is produced at 1.5-meter average post spacing for all 92 Indiana Counties covering more than 36,420 square miles. New LiDAR data was...

  15. Nacelle LiDAR online wind field reconstruction applied to feedforward pitch control

    Science.gov (United States)

    GUILLEMIN, F.; DOMENICO, D. DI; NGUYEN, N.; SABIRON, G.; BOQUET, M.; GIRARD, N.; COUPIAC, O.

    2016-09-01

    This paper presents innovative filtering and reconstruction techniques of nacelle LiDAR data, and exploitation of obtained wind anticipation capabilities for wind turbine control strategy. The implemented algorithms are applied under industrial constraints, on a MAIA EOLIS wind turbine, equipped with a LEOSPHERE 5-beams pulsed LiDAR, during experimental campaigns of SMARTEOLE collaborative project.

  16. Have I Been Here Before? A Method for Detecting Loop Closure With LiDAR

    Science.gov (United States)

    2015-01-01

    Have I Been Here Before? A Method for Detecting Loop Closure With LiDAR by John G Rogers III and Jason M Gregory ARL-TR-7165 January...TR-7165 January 2015 Have I Been Here Before? A Method for Detecting Loop Closure With LiDAR John G Rogers III and Jason M Gregory...

  17. Wetland inundation mapping and change monitoring using landsat and airborne LiDAR data

    Science.gov (United States)

    This paper presents a new approach for mapping wetland inundation change using Landsat and LiDAR intensity data. In this approach, LiDAR data were used to derive highly accurate reference subpixel inundation percentage (SIP) maps at the 30-m resolution. The reference SIP maps were then used to est...

  18. Classification of Spruce and Pine Trees Using Active Hyperspectral LiDAR

    NARCIS (Netherlands)

    Vauhkonen, J.; Hakala, T.; Suomalainen, J.M.; Kaasalainen, S.; Nevalainen, O.; Vastaranta, M.; Holopainen, M.; Hyyppa, J.

    2013-01-01

    Most forest inventories based on the use of remote-sensing data produce the required species-specific information by fusing data from different sources (e.g., Light Detection And Ranging (LiDAR) and spectral data). We tested an active hyperspectral LiDAR instrument in a laboratory measurement of spr

  19. Investigating assumptions of crown archetypes for modelling LiDAR returns

    NARCIS (Netherlands)

    Calders, K.; Lewis, P.; Disney, M.; Verbesselt, J.; Herold, M.

    2013-01-01

    LiDAR has the potential to derive canopy structural information such as tree height and leaf area index (LAI), via models of the LiDAR signal. Such models often make assumptions regarding crown shape to simplify parameter retrieval and crown archetypes are typically assumed to contain a turbid mediu

  20. Mapping of landslides under dense vegetation cover using object - oriented analysis and LiDAR derivatives

    NARCIS (Netherlands)

    Van Den Eeckhout, Miet; Kerle, Norman; Hervas, Javier; Supper, Robert; Margottini, C.; Canuti, P.; Sassa, K.

    2013-01-01

    Light Detection and Ranging (LiDAR) and its wide range of derivative products have become a powerful tool in landslide research, particularly for landslide identification and landslide inventory mapping. In contrast to the many studies that use expert-based analysis of LiDAR derivatives to identify

  1. Object-oriented identification of forested landslides with derivatives of single pulse LiDAR data

    NARCIS (Netherlands)

    Eeckhaut, van den M.; Kerle, N.; Poesen, J.; Hervas, J.

    2012-01-01

    In contrast to the many studies that use expert-based analysis of LiDAR derivatives for landslide mapping in forested terrain, only few studies have attempted to develop (semi-)automatic methods for extracting landslides from LiDAR derivatives. While all these studies are pixel-based, it has not yet

  2. Jean Lafitte 2013, 1.0 Meter LiDAR, Classified point cloud

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of the Jean Lafitte,G13PD00214, 1.0 Meter LiDAR Survey Area in south of New Orleans and encompasses 77...

  3. FY12 St Johns River Water Management LiDAR Survey: Putnam (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of the FY12 St Johns River Water Management LiDAR Survey, project area in north-central Florida and...

  4. Remote sensing of Sonoran Desert vegetation structure and phenology with ground-based LiDAR

    Science.gov (United States)

    Sankey, Joel B.; Munson, Seth M.; Webb, Robert H.; Wallace, Cynthia S.A.; Duran, Cesar M.

    2015-01-01

    Long-term vegetation monitoring efforts have become increasingly important for understanding ecosystem response to global change. Many traditional methods for monitoring can be infrequent and limited in scope. Ground-based LiDAR is one remote sensing method that offers a clear advancement to monitor vegetation dynamics at high spatial and temporal resolution. We determined the effectiveness of LiDAR to detect intra-annual variability in vegetation structure at a long-term Sonoran Desert monitoring plot dominated by cacti, deciduous and evergreen shrubs. Monthly repeat LiDAR scans of perennial plant canopies over the course of one year had high precision. LiDAR measurements of canopy height and area were accurate with respect to total station survey measurements of individual plants. We found an increase in the number of LiDAR vegetation returns following the wet North American Monsoon season. This intra-annual variability in vegetation structure detected by LiDAR was attributable to a drought deciduous shrub Ambrosia deltoidea, whereas the evergreen shrub Larrea tridentata and cactus Opuntia engelmannii had low variability. Benefits of using LiDAR over traditional methods to census desert plants are more rapid, consistent, and cost-effective data acquisition in a high-resolution, 3-dimensional context. We conclude that repeat LiDAR measurements can be an effective method for documenting ecosystem response to desert climatology and drought over short time intervals and at detailed-local spatial scale.

  5. 2007 South Carolina LiDAR: Charleston (partial), Jasper, and Colleton Counties

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — LiDAR data collection was performed utilizing a Leica ALS-50 sensor, collecting multiple return x, y, and z data as well as intensity data. LiDAR data was processed...

  6. Genetic linkage mapping in an F2 perennial ryegrass population using DArT markers

    DEFF Research Database (Denmark)

    Tomaszewski, Céline; Byrne, Stephen; Foito, Alexandra;

    2012-01-01

    T markers, and a DArT array has recently been developed for the Lolium-Festuca complex. In this study, we report the first use of the DArTFest array to generate a genetic linkage map based on 326 markers in a Lolium perenne F2 population, consisting of 325 genotypes. For proof of concept, the map was used...

  7. Modelling Sensor and Target effects on LiDAR Waveforms

    Science.gov (United States)

    Rosette, J.; North, P. R.; Rubio, J.; Cook, B. D.; Suárez, J.

    2010-12-01

    The aim of this research is to explore the influence of sensor characteristics and interactions with vegetation and terrain properties on the estimation of vegetation parameters from LiDAR waveforms. This is carried out using waveform simulations produced by the FLIGHT radiative transfer model which is based on Monte Carlo simulation of photon transport (North, 1996; North et al., 2010). The opportunities for vegetation analysis that are offered by LiDAR modelling are also demonstrated by other authors e.g. Sun and Ranson, 2000; Ni-Meister et al., 2001. Simulations from the FLIGHT model were driven using reflectance and transmittance properties collected from the Howland Research Forest, Maine, USA in 2003 together with a tree list for a 200m x 150m area. This was generated using field measurements of location, species and diameter at breast height. Tree height and crown dimensions of individual trees were calculated using relationships established with a competition index determined for this site. Waveforms obtained by the Laser Vegetation Imaging Sensor (LVIS) were used as validation of simulations. This provided a base from which factors such as slope, laser incidence angle and pulse width could be varied. This has enabled the effect of instrument design and laser interactions with different surface characteristics to be tested. As such, waveform simulation is relevant for the development of future satellite LiDAR sensors, such as NASA’s forthcoming DESDynI mission (NASA, 2010), which aim to improve capabilities of vegetation parameter estimation. ACKNOWLEDGMENTS We would like to thank scientists at the Biospheric Sciences Branch of NASA Goddard Space Flight Center, in particular to Jon Ranson and Bryan Blair. This work forms part of research funded by the NASA DESDynI project and the UK Natural Environment Research Council (NE/F021437/1). REFERENCES NASA, 2010, DESDynI: Deformation, Ecosystem Structure and Dynamics of Ice. http

  8. LiDAR Analysis of Hector Mine Fault Scarp Degradation

    Science.gov (United States)

    Zhang, X.; Hudnut, K. W.; Glennie, C. L.; Sousa, F.; Stock, J. M.; Akciz, S. O.

    2014-12-01

    The Mw 7.1 right-lateral strike-slip Hector Mine earthquake occurred on 10/16/1999 and generated an approximately 48 km long surface rupture. The Lavic Lake fault and the central section of the Bullion fault and several lesser faults ruptured, characterized by maximum strike slip of 5.25 ±0.85 m [Treiman, 2002]. As a very remote and un-populated area of the Mojave Desert, southern California, the study area is highly favorable for fault degradation studies with essentially no influence from vegetation or human activity. Airborne LiDAR (light detection and ranging) data and terrestrial laser scanning (TLS) are used to evaluate the form and rate of degradation of scarps along the Hector Mine fault rupture, California, USA. Airborne LiDAR data were acquired in 2000 and 2012 and these data were differenced using a newly developed algorithm for point cloud matching, which is improved over prior methods by accounting for scan geometry error sources. Using the bi-temporal data (scrutinizing profiles from 2000 & 2012), parameters for a fault scarp diffusion model are estimated and then a simulation result is generated to predict the evolved landform shape at the time of the 2014 TLS data set. Results are checked against TLS 2014 data collected at five key sites within the maximum slip field study area. In the past, scarp degradation has been mostly investigated using traditional survey methods (e.g., measuring elevations of points in a line perpendicular to the scarp) that require time-consuming field work and tend to introduce bias and variance due to data limitations. Airborne, mobile and terrestrial LiDAR data offer great potential to precisely document and rigorously determine morphologic degradation of fault scarps [Hilley et al., 2010]. In the present study, a unique set of data have been acquired at three points in time across several classic types of fault scarps and offset fault zone features. This allows progress in assessing the fitting of functions and

  9. Applicability of Aerial Green LiDAR to a Large River in the Western United States

    Science.gov (United States)

    Conner, J. T.; Welcker, C. W.; Cooper, C.; Faux, R.; Butler, M.; Nayegandhi, A.

    2013-12-01

    In October 2012, aerial green LiDAR data were collected in the Snake River (within Idaho and Oregon) to test this emerging technology in a large river with poor water clarity. Six study areas (total of 30 river miles spread out over 250 river miles) were chosen to represent a variety of depths, channel types, and surface conditions to test the accuracy, depth penetration, data density of aerial green LiDAR. These characteristics along with cost and speed of acquisition were compared to other bathymetric survey techniques including rod surveys (total station and RTK-GPS), single-beam sonar, and multibeam echosounder (MBES). The green LiDAR system typically measured returns from the riverbed through 1-2 meters of water, which was less than one Secchi depth. However, in areas with steep banks or aquatic macrophytes, LiDAR returns from the riverbed were less frequent or non-existent. In areas of good return density, depths measured from green LiDAR data corresponded well with previously collected data sets from traditional bathymetric survey techniques. In such areas, the green LiDAR point density was much higher than both rod and single beam sonar surveys, yet lower than MBES. The green LiDAR survey was also collected more efficiently than all other methods. In the Snake River, green LiDAR does not provide a method to map the entire riverbed as it only receives bottom returns in shallow water, typically at the channel margins. However, green LiDAR does provide survey data that is an excellent complement to MBES, which is more effective at surveying the deeper portions of the channel. In some cases, the green LiDAR was able to provide data in areas that the MBES could not, often due to issues with navigating the survey boat in shallow water. Even where both MBES and green LiDAR mapped the river bottom, green LiDAR often provides more accurate data through a better angle of incidence and less shadowing than the MBES survey. For one MBES survey in 2013, the green LiDAR

  10. Multipath Estimation in Urban Environments from Joint GNSS Receivers and LiDAR Sensors

    Directory of Open Access Journals (Sweden)

    Antonio J. Fernández

    2012-10-01

    Full Text Available In this paper, multipath error on Global Navigation Satellite System (GNSS signals in urban environments is characterized with the help of Light Detection and Ranging (LiDAR measurements. For this purpose, LiDAR equipment and Global Positioning System (GPS receiver implementing a multipath estimating architecture were used to collect data in an urban environment. This paper demonstrates how GPS and LiDAR measurements can be jointly used to model the environment and obtain robust receivers. Multipath amplitude and delay are estimated by means of LiDAR feature extraction and multipath mitigation architecture. The results show the feasibility of integrating the information provided by LiDAR sensors and GNSS receivers for multipath mitigation.

  11. Multipath estimation in urban environments from joint GNSS receivers and LiDAR sensors.

    Science.gov (United States)

    Ali, Khurram; Chen, Xin; Dovis, Fabio; De Castro, David; Fernández, Antonio J

    2012-10-30

    In this paper, multipath error on Global Navigation Satellite System (GNSS) signals in urban environments is characterized with the help of Light Detection and Ranging (LiDAR) measurements. For this purpose, LiDAR equipment and Global Positioning System (GPS) receiver implementing a multipath estimating architecture were used to collect data in an urban environment. This paper demonstrates how GPS and LiDAR measurements can be jointly used to model the environment and obtain robust receivers. Multipath amplitude and delay are estimated by means of LiDAR feature extraction and multipath mitigation architecture. The results show the feasibility of integrating the information provided by LiDAR sensors and GNSS receivers for multipath mitigation.

  12. Getting the Most Neutrinos out of IsoDAR

    CERN Document Server

    Ciuffoli, Emilio; Mohammed, Hosam; Zhao, Fengyi; Deliyergiyev, Maksym

    2016-01-01

    Several experimental collaborations worldwide intend to test sterile neutrino models by measuring the disappearance of antineutrinos produced via isotope decay at rest (IsoDAR). The most advanced of these proposals have very similar setups, in which a proton beam strikes a target yielding neutrons which are absorbed by a high isotopic purity 7Li converter, yielding 8Li whose resulting decay yields the antineutrinos. In this note, we use FLUKA and GEANT4 simulations to investigate three proposed modifications of this standard proposal. In the first, the 7Li is replaced with 7Li compounds including a deuterium moderator. In the second, a gap is placed between the target and the converter to reduce the neutron bounce-back. Finally, we consider cooling the converter with liquid nitrogen. We find that these modifications can increase the antineutrino yield by as much as 50 percent. The first also substantially reduces the quantity of high purity 7Li which is needed.

  13. Full waveform hyperspectral LiDAR for terrestrial laser scanning.

    Science.gov (United States)

    Hakala, Teemu; Suomalainen, Juha; Kaasalainen, Sanna; Chen, Yuwei

    2012-03-26

    We present the design of a full waveform hyperspectral light detection and ranging (LiDAR) and the first demonstrations of its applications in remote sensing. The novel instrument produces a 3D point cloud with spectral backscattered reflectance data. This concept has a significant impact on remote sensing and other fields where target 3D detection and identification is crucial, such as civil engineering, cultural heritage, material processing, or geomorphological studies. As both the geometry and spectral information on the target are available from a single measurement, this technology will extend the scope of imaging spectroscopy into spectral 3D sensing. To demonstrate the potential of the instrument in the remote sensing of vegetation, 3D point clouds with backscattered reflectance and spectral indices are presented for a specimen of Norway spruce.

  14. Dynamic LiDAR-NDVI classification of fluvial landscape units

    Science.gov (United States)

    Ramírez-Núñez, Carolina; Parrot, Jean-François

    2015-04-01

    The lower basin of the Coatzacoalcos River is a wide floodplain in which, during the wet season, local and major flooding are distinguished. Both types of floods, intermittent and regional, are important in terms of resources; the regional flood sediments enrich the soils of the plains and intermittent floods allow obtaining aquatic resources for subsistence during the heatwave. In the floodplain different abandoned meanders and intermittent streams are quickly colonized by aquatic vegetation. However, from the 1990s, the Coatzacoalcos River floodplain has important topographic changes due to mining, road and bridges construction; erosion and sedimentation requires continuous parcel boundaries along with the increasing demand of channel reparation, embankments, levees and bridges associated to tributaries. NDVI data, LiDAR point cloud and various types of flood simulations taking into account the DTM are used to classify the dynamic landscape units. These units are associated to floods in relation with water resources, agriculture and livestock. In the study area, the first returns of the point cloud allow extracting vegetation strata. The last returns correspond to the bare earth surface, especially in this area with few human settlements. The surface that is not covered by trees or by aquatic vegetation, correspond to crops, pastures and bare soils. The classification is obtained by using the NDVI index coupled with vegetation strata and water bodies. The result shows that 47.96% of the area does not present active vegetation and it includes 31.53% of bare soils. Concerning the active vegetation, pastures, bushes and trees represent respectively 25.59%, 11.14% and 13.25%. The remaining 1.25% is distributed between water bodies with aquatic vegetation, trees and shrubs. Dynamic landscape units' classification represents a tool for monitoring water resources in a fluvial plain. This approach can be also applied to forest management, environmental services and

  15. S-DARS broadcast from inclined, elliptical orbits

    Science.gov (United States)

    Briskman, Robert D.; Prevaux, Robert J.

    2004-04-01

    The first Sirius spacecraft was launched on July 1, 2000. Exactly 5 months later, on December 1, the third spacecraft was launched, completing the three satellite S-DARS (Satellite Digital Audio Radio Service) constellation. The three satellites are deployed in inclined, elliptical, geosynchronous orbits, which allow seamless broadcast coverage to mobile users in the contiguous US. Terrestrial broadcast repeaters provide service in urban cores. The system is in operation, providing the first ever S-DARS service. The constellation design results in satellite ground tracks over North America with two satellites always above the equator. High elevation look angles from the mobile ground terminals to the satellites minimize performance degradation due to blockage, foliage attenuation and multi-path. The spacecraft were built by Space Systems/Loral using the 1300 bus modified for operation in high inclination orbits. Each spacecraft was launched using a dedicated Russian Proton booster. The satellite payload is a bent pipe repeater using 7.1 GHz for the uplink and 2.3 GHz for the broadcast transmission. The repeater high-power amplification stage consists of 32 Traveling Wave Tube Amplifiers phase combined to yield a total radio frequency output power of nearly 4 kW at saturated operation. The satellite antennas are mechanically steered to maintain the transmit beam centered on the Contiguous United States and the receive beam centered on the uplink earth station located in Vernon Valley, New Jersey. The satellite payload design and performance are described. The principal spacecraft bus systems are described with emphasis on improvements made for operation in the inclined, elliptical geosynchronous orbits.

  16. Estimating FPAR of maize canopy using airborne discrete-return LiDAR data.

    Science.gov (United States)

    Luo, Shezhou; Wang, Cheng; Xi, Xiaohuan; Pan, Feifei

    2014-03-10

    The fraction of absorbed photosynthetically active radiation (FPAR) is a key parameter for ecosystem modeling, crop growth monitoring and yield prediction. Ground-based FPAR measurements are time consuming and labor intensive. Remote sensing provides an alternative method to obtain repeated, rapid and inexpensive estimates of FPAR over large areas. LiDAR is an active remote sensing technology and can be used to extract accurate canopy structure parameters. A method to estimating FPAR of maize from airborne discrete-return LiDAR data was developed and tested in this study. The raw LiDAR point clouds were processed to separate ground returns from vegetation returns using a filter method over a maize field in the Heihe River Basin, northwest China. The fractional cover (fCover) of maize canopy was computed using the ratio of canopy return counts or intensity sums to the total of returns or intensities. FPAR estimation models were established based on linear regression analysis between the LiDAR-derived fCover and the field-measured FPAR (R(2) = 0.90, RMSE = 0.032, p LiDAR-predicted FPARs and results show that the LiDAR-predicted FPAR has a high accuracy (R(2) = 0.89, RMSE = 0.034). In summary, this study suggests that the airborne discrete-return LiDAR data could be adopted to accurately estimate FPAR of maize.

  17. Finkel, D. (2008). dar clase con la boca cerrada. Barcelona: Publicacions de la Universitat de València (Traducción de Óscar Barberá, título original: Teaching with your mouth shit, 2000)

    OpenAIRE

    Consuelo Navarro, Bertha

    2015-01-01

    El libro de Don Finkel, desde su título, dar clase con la boca cerrada provoca la imaginación e invita a lector a construir su comprensión de lo que puede significar y suponer crear entornos de aprendizaje. Para este maestro estadounidense, en el ejercicio pedagógico, aprender debe constituirse en el objetivo y enseñar en el medio; de esta premisa surge su esfuerzo por crear aquellas circunstancias que conduzcan al aprendizaje relevante en terceras personas.dar clase con la boca cerrada es la...

  18. ASTER GDEM validation using LiDAR data over coastal regions of Greenland

    DEFF Research Database (Denmark)

    Hvidegaard, Sine Munk; Sørensen, Louise Sandberg; Forsberg, René

    2011-01-01

    Elevation data from airborne Light Detection and Ranging (LiDAR) campaigns are used in an attempt to evaluate the accuracy of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) global digital elevation model (GDEM) in Greenland. The LiDAR elevation data set is characterized...... by a high spatial resolution of about 1 m and elevation accuracy of 20–30 cm root mean square error (RMSE). The LiDAR data sets used were acquired during ice-monitoring campaigns carried out from 2003 to 2008. The study areas include ice-free regions, local ice caps and the ice sheet margin. A linear error...

  19. An Algorithm to Identify and Localize Suitable Dock Locations from 3-D LiDAR Scans

    Science.gov (United States)

    2013-05-10

    Survey. Map data ©2013 Google 9 Data Collecting Process 5.3.2 In order to collect data, the LiDAR would be placed on a cart and a MATLAB ...program was used to collect data of one scan, or one 360 degree rotation, of the LiDAR . These scans were saved as MATLAB figures for visual reference...Locations from 3-D LiDAR Scans 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Graves, Mitchell Robert 5d. PROJECT NUMBER

  20. Individual Tree Segmentation from LiDAR Point Clouds for Urban Forest Inventory

    OpenAIRE

    Caiyun Zhang; Yuhong Zhou; Fang Qiu

    2015-01-01

    The objective of this study is to develop new algorithms for automated urban forest inventory at the individual tree level using LiDAR point cloud data. LiDAR data contain three-dimensional structure information that can be used to estimate tree height, base height, crown depth, and crown diameter. This allows precision urban forest inventory down to individual trees. Unlike most of the published algorithms that detect individual trees from a LiDAR-derived raster surface, we worked directly w...

  1. LiDAR-derived snowpack data sets from mixed conifer forests across the Western United States

    Science.gov (United States)

    Harpold, A. A.; Guo, Q.; Molotch, N.; Brooks, P. D.; Bales, R.; Fernandez-Diaz, J. C.; Musselman, K. N.; Swetnam, T. L.; Kirchner, P.; Meadows, M. W.; Flanagan, J.; Lucas, R.

    2014-03-01

    Airborne-based Light Detection and Ranging (LiDAR) offers the potential to measure snow depth and vegetation structure at high spatial resolution over large extents and thereby increase our ability to quantify snow water resources. Here we present airborne LiDAR data products at four Critical Zone Observatories (CZO) in the Western United States: Jemez River Basin, NM, Boulder Creek Watershed, CO, Kings River Experimental Watershed, CA, and Wolverton Basin, CA. We make publicly available snow depth data products (1 m2 resolution) derived from LiDAR with an estimated accuracy of <30 cm compared to limited in situ snow depth observations.

  2. 4D Near Real-Time Environmental Monitoring Using Highly Temporal LiDAR

    Science.gov (United States)

    Höfle, Bernhard; Canli, Ekrem; Schmitz, Evelyn; Crommelinck, Sophie; Hoffmeister, Dirk; Glade, Thomas

    2016-04-01

    The last decade has witnessed extensive applications of 3D environmental monitoring with the LiDAR technology, also referred to as laser scanning. Although several automatic methods were developed to extract environmental parameters from LiDAR point clouds, only little research has focused on highly multitemporal near real-time LiDAR (4D-LiDAR) for environmental monitoring. Large potential of applying 4D-LiDAR is given for landscape objects with high and varying rates of change (e.g. plant growth) and also for phenomena with sudden unpredictable changes (e.g. geomorphological processes). In this presentation we will report on the most recent findings of the research projects 4DEMON (http://uni-heidelberg.de/4demon) and NoeSLIDE (https://geomorph.univie.ac.at/forschung/projekte/aktuell/noeslide/). The method development in both projects is based on two real-world use cases: i) Surface parameter derivation of agricultural crops (e.g. crop height) and ii) change detection of landslides. Both projects exploit the "full history" contained in the LiDAR point cloud time series. One crucial initial step of 4D-LiDAR analysis is the co-registration over time, 3D-georeferencing and time-dependent quality assessment of the LiDAR point cloud time series. Due to the high amount of datasets (e.g. one full LiDAR scan per day), the procedure needs to be performed fully automatically. Furthermore, the online near real-time 4D monitoring system requires to set triggers that can detect removal or moving of tie reflectors (used for co-registration) or the scanner itself. This guarantees long-term data acquisition with high quality. We will present results from a georeferencing experiment for 4D-LiDAR monitoring, which performs benchmarking of co-registration, 3D-georeferencing and also fully automatic detection of events (e.g. removal/moving of reflectors or scanner). Secondly, we will show our empirical findings of an ongoing permanent LiDAR observation of a landslide (Gresten

  3. Frontiers in Using LiDAR to Analyze Urban Landscape Heterogeneity

    Science.gov (United States)

    Singh, Kunwar Krishna Veer

    Light Detection and Ranging (LiDAR) technology has facilitated extraordinary advances in our ability to remotely sense precise details of both built and natural environments. The inherent complexity of urban landscapes and the massive data volumes produced by LiDAR require unique methodological considerations for big data remote sensing over large metropolitan regions. The heterogeneous landscapes of the rapidly urbanizing Charlotte Metropolitan Region of North Carolina provided an ideal testing ground for developing methods of analysis for urban ecosystems over large regional extents, including: (1) fusion of LiDAR digital surface models (DSMs) with Landsat TM imagery to balance spatial resolution, data volume, and mapping accuracy of urban land covers, (2) comparison of LiDAR-derived metrics to fine grain optical imagery -- and their integration -- for detecting forest understory plant invaders, and (3) data reduction techniques for computationally efficient estimation of aboveground woody biomass in urban forests. In Chapter 1, I examined tradeoffs between potential gains in mapping accuracy and computational costs by integrating DSMs (structural and intensity) extracted from LiDAR with TM imagery and evaluating the degree to which TM, LiDAR, and LiDAR-TM fusion data discriminated land covers. I used Maximum Likelihood and Classification Tree algorithms to classify TM data, LiDAR data, and LiDAR-TM fusions. I assessed the relative contributions of LiDAR DSMs to map classification accuracy and identified an optimal spatial resolution of LiDAR DSMs for large area assessments of urban land cover. In Chapter 2, I analyzed combinations of datasets developed from categorized LiDAR-derived variables (Overstory, Understory, Topography, and Overall Vegetation Characteristics) and IKONOS imagery ( Optical) to detect and map the understory plant invader, Ligustrum sinense, using Random Forest (RF) and logistic regression (LR) algorithms, and I assessed the relative

  4. LiDAR DTM: artifacts, and correction for river altitudes

    Directory of Open Access Journals (Sweden)

    Jean-François Parrot

    2016-01-01

    Full Text Available Los datos LiDAR permiten generar Modelos Digitales de Elevación (MDE de alta resolución, sin embargo, algunos artefactos resultantes del método de interpolación utilizado afectan su exactitud y precisión. Esta observación concierne, entre otros, a los MDE generados por el Instituto Nacional de Estadística y Geografía (INEGI, especialmente los Modelos Digitales de Terreno (MDT, que se relacionan con la superficie terrestre. Estos artefactos corresponden a facetas triangulares en elevaciones, meandros, y superficies de los ríos. Los tratamientos desarrollados en esta investigación disminuyen y/o eliminan dichos artefactos mejorando los MDT. Cálculos basados en el Error Cuadrá- tico Medio de la Rugosidad y el Error Cuadrático Medio de la elevación muestran que el método presentado en este trabajo mejora la precisión de los productos digitales, lo que permite realizar simulaciones eficaces y mediciones precisas.

  5. 2008 - 2009 Oregon Department of Geology and Mineral Industries (DOGAMI) South Coast LiDAR Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Oregon Department of Geology and Mineral Industries (DOGAMI) contracted with Watershed Sciences, Inc. to collect high resolution topographic LiDAR data for...

  6. Development and mapping of DArT markers within the Festuca - Lolium complex

    DEFF Research Database (Denmark)

    Kopecký, David; Bartos, Jan; Lukaszewski, Adam J

    2009-01-01

    Background Grasses are among the most important and widely cultivated plants on Earth. They provide high quality fodder for livestock, are used for turf and amenity purposes, and play a fundamental role in environment protection. Among cultivated grasses, species within the Festuca-Lolium complex...... predominate, especially in temperate regions. To facilitate high-throughput genome profiling and genetic mapping within the complex, we have developed a Diversity Arrays Technology (DArT) array for five grass species: F. pratensis, F. arundinacea, F. glaucescens, L. perenne and L. multiflorum. Results The DAr......T markers identified in every single genotype varied from 821 to 1852. To test the usefulness of DArTFest array for physical mapping, DArT markers were assigned to each of the seven chromosomes of F. pratensis using single chromosome substitution lines while recombinants of F. pratensis chromosome 3 were...

  7. 2009 National Renewable Energy Laboratory/Boston Redevelopment Authority Topographic LiDAR: Boston, Massachusetts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Alliance for Sustainable Energy, LLC contracted with Sanborn to provide LiDAR mapping services for the Boston area. Utilizing multi-return systems, Light...

  8. 2009 National Renewable Energy Labratory/Boston Redevelopment Authority Topographic LiDAR: Boston, Massachusetts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Alliance for Sustainable Energy, LLC contracted with Sanborn to provide LiDAR mapping services for the Boston area. Utilizing multi-return systems, Light...

  9. 2010 U.S. Geological Survey Topographic LiDAR: Atchafalaya Basin, Louisiana

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of the Atchafalaya Basin in south-central Louisiana. The entire survey area encompasses 981 square miles....

  10. LiDAR Relative Reflectivity Surface (2011) for the St. Thomas East End Reserve, St. Thomas

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a LiDAR (Light Detection & Ranging) 0.3x0.3 meter resolution relative seafloor reflectivity surface for the St. Thomas East End Reserve...

  11. 2010 U.S. Geological Survey Topographic LiDAR: Atchafalaya Basin, Louisiana

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of the Atchafalaya Basin in south-central Louisiana. The entire survey area encompasses 981 square...

  12. 2011 Federal Emergency Management Agency (FEMA) Topographic LiDAR: Quinnipiac River Watershed, Connecticut

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Quinnipiac AOI consists of one 443 square mile area. Ground Control is collected throughout the AOI for use in the processing of LiDAR data to ensure data...

  13. 2010 U.S. Geological Survey (USGS) Topographic LiDAR: San Francisco Bay, California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The primary purpose of this project was to develop a consistent and accurate surface elevation dataset derived from high-accuracy Light Detection and Ranging (LiDAR)...

  14. LiDAR Elevation Data Collection - Putnam County, NY, 2008 (NYSDEC)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Summary of the surface elevation data collection project in Putnam County, NY (NYSDEC) 2008. Products generated include LiDAR point data in LAS Binary format v1.1....

  15. Forest Roads Mapped Using LiDAR in Steep Forested Terrain

    Directory of Open Access Journals (Sweden)

    Russell A. White

    2010-04-01

    Full Text Available LiDAR-derived digital elevation models can reveal road networks located beneath dense forest canopy. This study tests the accuracy of forest road characteristics mapped using LiDAR in the Santa Cruz Mountains, CA. The position, gradient, and total length of a forest haul road were accurately extracted using a 1 m DEM. In comparison to a field-surveyed centerline, the LiDAR-derived road exhibited a positional accuracy of 1.5 m, road grade measurements within 0.53% mean absolute difference, and total road length within 0.2% of the field-surveyed length. Airborne LiDAR can provide thorough and accurate road inventory data to support forest management and watershed assessment activities.

  16. 2008 - 2009 Oregon Department of Geology and Mineral Industries (DOGAMI) South Coast LiDAR Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Oregon Department of Geology & Mineral Industries (DOGAMI) contracted with Watershed Sciences, Inc. to collect high resolution topographic LiDAR data for...

  17. 2006 Florida LiDAR: Escambia, Santa Rosa, and Walton Counties

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — ESCAMBIA: The Light Detection and Ranging (LiDAR) LAS dataset is a survey of select areas within Escambia County, Florida. These data were produced for Dewberry and...

  18. Case of rhesus antigen weak D type 4.2. (DAR category detection

    Directory of Open Access Journals (Sweden)

    L. L. Golovkina

    2015-01-01

    Full Text Available Serological methods of Rhesus antigens identification in humans cannot identify D-antigen variants. In this article the serological characteristics of Rhesus antigen D weak type 4.2. (Category DAR are described.

  19. 2008 NWFWMD (Northwest Florida Water Management District) Florida LiDAR: Inland Okaloosa County

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This Light Detection and Ranging (LiDAR) LAS dataset is a survey of inland Okaloosa County, Florida not covered in the 2008 Florida Department of Emergency...

  20. 2008 Northwest Florida Water Management District (NWFWMD) LiDAR: Inland Okaloosa County

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This Light Detection and Ranging (LiDAR) LAS dataset is a survey of inland Okaloosa County, Florida not covered in the 2008 Florida Department of Emergency...

  1. 2007 Southwest Florida Water Management District (SWFWMD) LiDAR: Hernando County

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is one component of a digital terrain model (DTM) for the Southwest Florida Water Management Districts FY2006 Digital Orthophoto (B089) and LiDAR...

  2. 2012 USACE Post Sandy Topographic LiDAR: Rhode Island and Massachusetts Coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This topographic elevation point data derived from multiple return light detection and ranging (LiDAR) represents 354.272 square miles of coastline for Rhode Island...

  3. 2012 USACE Post Hurricane Sandy Topographic LiDAR: Rhode Island and Massachusetts Coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This topographic elevation point data derived from multiple return light detection and ranging (LiDAR) represents 354.272 square miles of coastline for Rhode Island...

  4. 2009 Federal Emergency Management Agency (FEMA) Topographic LiDAR: Fort Kent, Maine

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Camp Dresser McKee Inc. contracted with Sanborn Map Company to provide LiDAR mapping services for Fort Kent, Maine. Utilizing multi-return systems, Light Detection...

  5. 2007 Southwest Florida Water Management District (SWFWMD) LiDAR: Hillsborough/Little Manatee Districts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — EarthData International collected ADS-50 derived LiDAR over a portion of Hillsborough and Manatee Counties with a one meter post spacing. The period of collection...

  6. 2009 Puget Sound Lidar Consortium (PSLC) Topographic LiDAR: Nooksack River

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WS) collected Light Detection and Ranging (LiDAR) data of the Nooksack River in Washington on February 20th - 22nd, 2009. The total area of...

  7. 2006-2008 PAMAP LiDAR Data of Pennsylvania (Northern Counties)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of classified LiDAR (Light Detection and Ranging) elevation points produced by the PAMAP Program. PAMAP data are organized into blocks, which...

  8. 2006-2008 PAMAP LiDAR Data of Pennsylvania (Southern Counties)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of classified LiDAR (Light Detection and Ranging) elevation points produced by the PAMAP Program. Additional information is available at the...

  9. 2009 Puget Sound Lidar Consortium (PSLC) Topographic LiDAR: Nooksack River

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WS) collected Light Detection and Ranging (LiDAR) data of the Nooksack River in Washington on February 20th - 22nd, 2009. The total area...

  10. El humor es cosa seria

    OpenAIRE

    1997-01-01

    La capacidad de goce, trabajo y sobre todo el humor constituyen un criterio importante en la evaluación psicodiagnóstica, a pesar de ser a menudo, un aspecto excluido de los informes. Una razón de dicha exclusión podría ser el hecho de no contribuir por sí mismo a incluir al sujeto evaluado en una categoría psicopatológica. Otra razón que se suma a la anterior, es que el “ sentido del humor” que surge durante el transcurso de un proceso psicodiagnóstico exige de parte del que lo administra un...

  11. General(es) remisión de V. escuelas general(es).

    OpenAIRE

    2011-01-01

    [ES] Definición del término General(es) remisión de V. escuelas general(es). en el diccionario Dicter. [EN] Definition of the word General(es) remisión de V. escuelas general(es). in the dictionary Dicter.

  12. LiDAR Point Cloud and Stereo Image Point Cloud Fusion

    Science.gov (United States)

    2013-09-01

    produce more precise true orthophotos. Outside of the urban environment, forest management has started to engage the utility of LiDAR point cloud data...and tree health information, resulting in a complete model of the forest inventory. LiDAR collected point clouds and stereo-image-derived point...NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS Approved for public release; distribution is unlimited LIDAR POINT CLOUD

  13. Joint hierarchical models for sparsely sampled high-dimensional LiDAR and forest variables

    OpenAIRE

    Finley, Andrew O.; Banerjee, Sudipto; Zhou, Yuzhen; Cook, Bruce D; Babcock, Chad

    2016-01-01

    Recent advancements in remote sensing technology, specifically Light Detection and Ranging (LiDAR) sensors, provide the data needed to quantify forest characteristics at a fine spatial resolution over large geographic domains. From an inferential standpoint, there is interest in prediction and interpolation of the often sparsely sampled and spatially misaligned LiDAR signals and forest variables. We propose a fully process-based Bayesian hierarchical model for above ground biomass (AGB) and L...

  14. Aboveground Biomass Modeling from Field and LiDAR Data in Brazilian Amazon Tropical Rain Forest

    Science.gov (United States)

    Silva, C. A.; Hudak, A. T.; Vierling, L. A.; Keller, M. M.; Klauberg Silva, C. K.

    2015-12-01

    Tropical forests are an important component of global carbon stocks, but tropical forest responses to climate change are not sufficiently studied or understood. Among remote sensing technologies, airborne LiDAR (Light Detection and Ranging) may be best suited for quantifying tropical forest carbon stocks. Our objective was to estimate aboveground biomass (AGB) using airborne LiDAR and field plot data in Brazilian tropical rain forest. Forest attributes such as tree density, diameter at breast height, and heights were measured at a combination of square plots and linear transects (n=82) distributed across six different geographic zones in the Amazon. Using previously published allometric equations, tree AGB was computed and then summed to calculate total AGB at each sample plot. LiDAR-derived canopy structure metrics were also computed at each sample plot, and random forest regression modelling was applied to predict AGB from selected LiDAR metrics. The LiDAR-derived AGB model was assessed using the random forest explained variation, adjusted coefficient of determination (Adj. R²), root mean square error (RMSE, both absolute and relative) and BIAS (both absolute and relative). Our findings showed that the 99th percentile of height and height skewness were the best LiDAR metrics for AGB prediction. The AGB model using these two best predictors explained 59.59% of AGB variation, with an Adj. R² of 0.92, RMSE of 33.37 Mg/ha (20.28%), and bias of -0.69 (-0.42%). This study showed that LiDAR canopy structure metrics can be used to predict AGC stocks in Tropical Forest with acceptable precision and accuracy. Therefore, we conclude that there is good potential to monitor carbon sequestration in Brazilian Tropical Rain Forest using airborne LiDAR data, large field plots, and the random forest algorithm.

  15. Change Detection from differential airborne LiDAR using a weighted Anisotropic Iterative Closest Point Algorithm

    Science.gov (United States)

    Zhang, X.; Kusari, A.; Glennie, C. L.; Oskin, M. E.; Hinojosa-Corona, A.; Borsa, A. A.; Arrowsmith, R.

    2013-12-01

    Differential LiDAR (Light Detection and Ranging) from repeated surveys has recently emerged as an effective tool to measure three-dimensional (3D) change for applications such as quantifying slip and spatially distributed warping associated with earthquake ruptures, and examining the spatial distribution of beach erosion after hurricane impact. Currently, the primary method for determining 3D change is through the use of the iterative closest point (ICP) algorithm and its variants. However, all current studies using ICP have assumed that all LiDAR points in the compared point clouds have uniform accuracy. This assumption is simplistic given that the error for each LiDAR point is variable, and dependent upon highly variable factors such as target range, angle of incidence, and aircraft trajectory accuracy. Therefore, to rigorously determine spatial change, it would be ideal to model the random error for every LiDAR observation in the differential point cloud, and use these error estimates as apriori weights in the ICP algorithm. To test this approach, we implemented a rigorous LiDAR observation error propagation method to generate estimated random error for each point in a LiDAR point cloud, and then determine 3D displacements between two point clouds using an anistropic weighted ICP algorithm. The algorithm was evaluated by qualitatively and quantitatively comparing post earthquake slip estimates from the 2010 El Mayor-Cucapah Earthquake between a uniform weight and anistropically weighted ICP algorithm, using pre-event LiDAR collected in 2006 by Instituto Nacional de Estadística y Geografía (INEGI), and post-event LiDAR collected by The National Center for Airborne Laser Mapping (NCALM).

  16. Use of LiDAR to Assist in Delineating Waters of the United States, Including Wetlands

    Science.gov (United States)

    2014-03-01

    wetlands and uplands ( Hogg and Hol- land 2008) and better able to model relationships between vegetation and elevation (Moeslund et al. 2011) than DEMs...rugosa) (speckled alder) could not be distinguished from surrounding upland forest by using topographic LiDAR data alone ( Hogg and Holland 2008...gradual transition from upland to wetland ( Hogg and Holland 2008). Therefore, topographic patterns discerned using LiDAR data should be verified in the

  17. Adaptive Covariance Estimation Method for LiDAR-Aided Multi-Sensor Integrated Navigation Systems

    Directory of Open Access Journals (Sweden)

    Shifei Liu

    2015-01-01

    Full Text Available The accurate estimation of measurements covariance is a fundamental problem in sensors fusion algorithms and is crucial for the proper operation of filtering algorithms. This paper provides an innovative solution for this problem and realizes the proposed solution on a 2D indoor navigation system for unmanned ground vehicles (UGVs that fuses measurements from a MEMS-grade gyroscope, speed measurements and a light detection and ranging (LiDAR sensor. A computationally efficient weighted line extraction method is introduced, where the LiDAR intensity measurements are used, such that the random range errors and systematic errors due to surface reflectivity in LiDAR measurements are considered. The vehicle pose change is obtained from LiDAR line feature matching, and the corresponding pose change covariance is also estimated by a weighted least squares-based technique. The estimated LiDAR-based pose changes are applied as periodic updates to the Inertial Navigation System (INS in an innovative extended Kalman filter (EKF design. Besides, the influences of the environment geometry layout and line estimation error are discussed. Real experiments in indoor environment are performed to evaluate the proposed algorithm. The results showed the great consistency between the LiDAR-estimated pose change covariance and the true accuracy. Therefore, this leads to a significant improvement in the vehicle’s integrated navigation accuracy.

  18. Airborne Dual-Wavelength LiDAR Data for Classifying Land Cover

    Directory of Open Access Journals (Sweden)

    Cheng-Kai Wang

    2014-01-01

    Full Text Available This study demonstrated the potential of using dual-wavelength airborne light detection and ranging (LiDAR data to classify land cover. Dual-wavelength LiDAR data were acquired from two airborne LiDAR systems that emitted pulses of light in near-infrared (NIR and middle-infrared (MIR lasers. The major features of the LiDAR data, such as surface height, echo width, and dual-wavelength amplitude, were used to represent the characteristics of land cover. Based on the major features of land cover, a support vector machine was used to classify six types of suburban land cover: road and gravel, bare soil, low vegetation, high vegetation, roofs, and water bodies. Results show that using dual-wavelength LiDAR-derived information (e.g., amplitudes at NIR and MIR wavelengths could compensate for the limitations of using single-wavelength LiDAR information (i.e., poor discrimination of low vegetation when classifying land cover.

  19. The first genetic map of pigeon pea based on diversity arrays technology (DArT) markers

    Indian Academy of Sciences (India)

    Shi Ying Yang; Rachit A. Saxena; Pawan L. Kulwal; Gavin J. Ash; Anuja Dubey; John D. I. Harper; Hari D. Upadhyaya; Ragini Gothalwal; Andrzej Kilian; Rajeev K. Varshney

    2011-04-01

    With an objective to develop a genetic map in pigeon pea (Cajanus spp.), a total of 554 diversity arrays technology (DArT) markers showed polymorphism in a pigeon pea F2 mapping population of 72 progenies derived from an interspecific cross of ICP 28 (Cajanus cajan) and ICPW 94 (Cajanus scarabaeoides). Approximately 13% of markers did not conform to expected segregation ratio. The total number of DArT marker loci segregating in Mendelian manner was 405 with 73.1% ($P \\gt 0.001$) of DArT markers having unique segregation patterns. Two groups of genetic maps were generated using DArT markers. While the maternal genetic linkage map had 122 unique DArT maternal marker loci, the paternal genetic linkage map has a total of 172 unique DArT paternal marker loci. The length of these two maps covered 270.0 cM and 451.6 cM, respectively. These are the first genetic linkage maps developed for pigeon pea, and this is the first report of genetic mapping in any grain legume using diversity arrays technology.

  20. On the impact of a refined stochastic model for airborne LiDAR measurements

    Science.gov (United States)

    Bolkas, Dimitrios; Fotopoulos, Georgia; Glennie, Craig

    2016-09-01

    Accurate topographic information is critical for a number of applications in science and engineering. In recent years, airborne light detection and ranging (LiDAR) has become a standard tool for acquiring high quality topographic information. The assessment of airborne LiDAR derived DEMs is typically based on (i) independent ground control points and (ii) forward error propagation utilizing the LiDAR geo-referencing equation. The latter approach is dependent on the stochastic model information of the LiDAR observation components. In this paper, the well-known statistical tool of variance component estimation (VCE) is implemented for a dataset in Houston, Texas, in order to refine the initial stochastic information. Simulations demonstrate the impact of stochastic-model refinement for two practical applications, namely coastal inundation mapping and surface displacement estimation. Results highlight scenarios where erroneous stochastic information is detrimental. Furthermore, the refined stochastic information provides insights on the effect of each LiDAR measurement in the airborne LiDAR error budget. The latter is important for targeting future advancements in order to improve point cloud accuracy.

  1. ¿Qué es estructura?

    OpenAIRE

    Aroca Hernández-Ros, Ricardo

    1999-01-01

    La palabra Arquitectura para nosotros tiene una significación obvia, e incluso podríamos considerar que es una palabra reservada, es decir, que no debe emplearse en otro contexto; en realidad se emplea en el sentido de Orden Superior. La arquitectura de microprocesadores es un ejemplo del empleo del término con sentido bastante alejado del nuestro.

  2. Classification of LiDAR Data with Point Based Classification Methods

    Science.gov (United States)

    Yastikli, N.; Cetin, Z.

    2016-06-01

    LiDAR is one of the most effective systems for 3 dimensional (3D) data collection in wide areas. Nowadays, airborne LiDAR data is used frequently in various applications such as object extraction, 3D modelling, change detection and revision of maps with increasing point density and accuracy. The classification of the LiDAR points is the first step of LiDAR data processing chain and should be handled in proper way since the 3D city modelling, building extraction, DEM generation, etc. applications directly use the classified point clouds. The different classification methods can be seen in recent researches and most of researches work with the gridded LiDAR point cloud. In grid based data processing of the LiDAR data, the characteristic point loss in the LiDAR point cloud especially vegetation and buildings or losing height accuracy during the interpolation stage are inevitable. In this case, the possible solution is the use of the raw point cloud data for classification to avoid data and accuracy loss in gridding process. In this study, the point based classification possibilities of the LiDAR point cloud is investigated to obtain more accurate classes. The automatic point based approaches, which are based on hierarchical rules, have been proposed to achieve ground, building and vegetation classes using the raw LiDAR point cloud data. In proposed approaches, every single LiDAR point is analyzed according to their features such as height, multi-return, etc. then automatically assigned to the class which they belong to. The use of un-gridded point cloud in proposed point based classification process helped the determination of more realistic rule sets. The detailed parameter analyses have been performed to obtain the most appropriate parameters in the rule sets to achieve accurate classes. The hierarchical rule sets were created for proposed Approach 1 (using selected spatial-based and echo-based features) and Approach 2 (using only selected spatial-based features

  3. Prevenir la enfermedad es la mejor estrategia para mejorar la salud

    Directory of Open Access Journals (Sweden)

    José Alberto Mainieri-Hidalgo

    2011-01-01

    Full Text Available La salud es el bien más preciado para el ser humano, de lo cual toma consciencia sobre todo al perderla, o cuando la pérdida ocurre a un ser querido. Por tal motivo, una de las tareas fundamentales del Estado es garantizar la mejor salud posible a los ciudadanos, y esto en Costa Rica se ha hecho en forma muy eficiente, tanto que los indicadores de salud son de los mejores del mundo. Esto no es casual, sino el producto de decisiones políticas del pasado de costarricenses asertivos. Hoy el país enfrenta un gran reto con el crecimiento en la demanda de servicios públicos y el incremento en su costo. Para mantener el legado es preciso tomar decisiones igual de visionarias. Se señala como un alto riesgo de desmejorar estos indicadores, el concentrar los esfuerzos y presupuestos en tratar las enfermedades en sus etapas finales y, por el contrario, se propone dar prioridad a la prevención, con base en el hecho de que las principales causas de mortalidad prematura en los costarricenses, se asocian con factores de riesgo prevenibles. Se recomienda la educación como el camino para prevenir la enfermedad, y se debe involucrar a profesionales en impartir la “educación para la salud”, dirigida primero y formalmente a niños y adolescentes.

  4. Parallel Landscape Driven Data Reduction & Spatial Interpolation Algorithm for Big LiDAR Data

    Directory of Open Access Journals (Sweden)

    Rahil Sharma

    2016-06-01

    Full Text Available Airborne Light Detection and Ranging (LiDAR topographic data provide highly accurate digital terrain information, which is used widely in applications like creating flood insurance rate maps, forest and tree studies, coastal change mapping, soil and landscape classification, 3D urban modeling, river bank management, agricultural crop studies, etc. In this paper, we focus mainly on the use of LiDAR data in terrain modeling/Digital Elevation Model (DEM generation. Technological advancements in building LiDAR sensors have enabled highly accurate and highly dense LiDAR point clouds, which have made possible high resolution modeling of terrain surfaces. However, high density data result in massive data volumes, which pose computing issues. Computational time required for dissemination, processing and storage of these data is directly proportional to the volume of the data. We describe a novel technique based on the slope map of the terrain, which addresses the challenging problem in the area of spatial data analysis, of reducing this dense LiDAR data without sacrificing its accuracy. To the best of our knowledge, this is the first ever landscape-driven data reduction algorithm. We also perform an empirical study, which shows that there is no significant loss in accuracy for the DEM generated from a 52% reduced LiDAR dataset generated by our algorithm, compared to the DEM generated from an original, complete LiDAR dataset. For the accuracy of our statistical analysis, we perform Root Mean Square Error (RMSE comparing all of the grid points of the original DEM to the DEM generated by reduced data, instead of comparing a few random control points. Besides, our multi-core data reduction algorithm is highly scalable. We also describe a modified parallel Inverse Distance Weighted (IDW spatial interpolation method and show that the DEMs it generates are time-efficient and have better accuracy than the one’s generated by the traditional IDW method.

  5. Estimation of effective plant area index for South Korean forests using LiDAR system

    Institute of Scientific and Technical Information of China (English)

    KWAK; Doo-Ahn; LEE; Woo-Kyun; KAFATOS; Menas; SON; Yowhan; CHO; Hyun-Kook; LEE; Seung-Ho

    2010-01-01

    Light Detection and Ranging(LiDAR) systems can be used to estimate both vertical and horizontal forest structure.Woody components,the leaves of trees and the understory can be described with high precision,using geo-registered 3D-points.Based on this concept,the Effective Plant Area Indices(PAIe) for areas of Korean Pine(Pinus koraiensis),Japanese Larch(Larix leptolepis) and Oak(Quercus spp.) were estimated by calculating the ratio of intercepted and incident LIDAR laser rays for the canopies of the three forest types.Initially,the canopy gap fraction(GLiDAR) was generated by extracting the LiDAR data reflected from the canopy surface,or inner canopy area,using k-means statistics.The LiDAR-derived PAIe was then estimated by using GLIDAR with the Beer-Lambert law.A comparison of the LiDAR-derived and field-derived PAIe revealed the coefficients of determination for Korean Pine,Japanese Larch and Oak to be 0.82,0.64 and 0.59,respectively.These differences between field-based and LIDAR-based PAIe for the different forest types were attributed to the amount of leaves and branches in the forest stands.The absence of leaves,in the case of both Larch and Oak,meant that the LiDAR pulses were only reflected from branches.The probability that the LiDAR pulses are reflected from bare branches is low as compared to the reflection from branches with a high leaf density.This is because the size of the branch is smaller than the resolution across and along the 1 meter LIDAR laser track.Therefore,a better predictive accuracy would be expected for the model if the study would be repeated in late spring when the shoots and leaves of the deciduous trees begin to appear.

  6. Estimation of effective plant area index for South Korean forests using LiDAR system.

    Science.gov (United States)

    Kwak, Doo-Ahn; Lee, Woo-Kyun; Kafatos, Menas; Son, Yowhan; Cho, Hyun-Kook; Lee, Seung-Ho

    2010-07-01

    Light Detection and Ranging (LiDAR) systems can be used to estimate both vertical and horizontal forest structure. Woody components, the leaves of trees and the understory can be described with high precision, using geo-registered 3D-points. Based on this concept, the Effective Plant Area Indices (PAI(e)) for areas of Korean Pine (Pinus koraiensis), Japanese Larch (Larix leptolepis) and Oak (Quercus spp.) were estimated by calculating the ratio of intercepted and incident LIDAR laser rays for the canopies of the three forest types. Initially, the canopy gap fraction (G ( LiDAR )) was generated by extracting the LiDAR data reflected from the canopy surface, or inner canopy area, using k-means statistics. The LiDAR-derived PAI(e) was then estimated by using G ( LIDAR ) with the Beer-Lambert law. A comparison of the LiDAR-derived and field-derived PAI(e) revealed the coefficients of determination for Korean Pine, Japanese Larch and Oak to be 0.82, 0.64 and 0.59, respectively. These differences between field-based and LIDAR-based PAI(e) for the different forest types were attributed to the amount of leaves and branches in the forest stands. The absence of leaves, in the case of both Larch and Oak, meant that the LiDAR pulses were only reflected from branches. The probability that the LiDAR pulses are reflected from bare branches is low as compared to the reflection from branches with a high leaf density. This is because the size of the branch is smaller than the resolution across and along the 1 meter LIDAR laser track. Therefore, a better predictive accuracy would be expected for the model if the study would be repeated in late spring when the shoots and leaves of the deciduous trees begin to appear.

  7. Registration of Aerial Image with Airborne LiDAR Data Based on Plücker Line

    OpenAIRE

    SHENG Qinghong; Chen, Shuwen; FEI Lijia; Liu, Jianfeng; Wang, Huinan

    2015-01-01

    Registration of aerial image with airborne LiDAR data is a key to feature extraction. A registration model based on Plücker line is proposed. The relative position and attitude relationship between the conjugate lines in LiDAR and image is determined based on Plücker linear equation, which describes line transformation in space, then coplanarity condition equation is established. Finally, coordinate transformation between image point and corresponding LiDAR point is achieved by the ...

  8. Extraction of Mangrove Biophysical Parameters Using Airborne LiDAR

    Directory of Open Access Journals (Sweden)

    Poonsak Miphokasap

    2013-04-01

    Full Text Available Tree parameter determinations using airborne Light Detection and Ranging (LiDAR have been conducted in many forest types, including coniferous, boreal, and deciduous. However, there are only a few scientific articles discussing the application of LiDAR to mangrove biophysical parameter extraction at an individual tree level. The main objective of this study was to investigate the potential of using LiDAR data to estimate the biophysical parameters of mangrove trees at an individual tree scale. The Variable Window Filtering (VWF and Inverse Watershed Segmentation (IWS methods were investigated by comparing their performance in individual tree detection and in deriving tree position, crown diameter, and tree height using the LiDAR-derived Canopy Height Model (CHM. The results demonstrated that each method performed well in mangrove forests with a low percentage of crown overlap conditions. The VWF method yielded a slightly higher accuracy for mangrove parameter extractions from LiDAR data compared with the IWS method. This is because the VWF method uses an adaptive circular filtering window size based on an allometric relationship. As a result of the VWF method, the position measurements of individual tree indicated a mean distance error value of 1.10 m. The individual tree detection showed a kappa coefficient of agreement (K value of 0.78. The estimation of crown diameter produced a coefficient of determination (R2 value of 0.75, a Root Mean Square Error of the Estimate (RMSE value of 1.65 m, and a Relative Error (RE value of 19.7%. Tree height determination from LiDAR yielded an R2 value of 0.80, an RMSE value of 1.42 m, and an RE value of 19.2%. However, there are some limitations in the mangrove parameters derived from LiDAR. The results indicated that an increase in the percentage of crown overlap (COL results in an accuracy decrease of the mangrove parameters extracted from the LiDAR-derived CHM, particularly for crown measurements. In this

  9. Spinning a laser web: predicting spider distributions using LiDAR.

    Science.gov (United States)

    Vierling, K T; Bässler, C; Brandl, R; Vierling, L A; Weiss, I; Müller, J

    2011-03-01

    LiDAR remote sensing has been used to examine relationships between vertebrate diversity and environmental characteristics, but its application to invertebrates has been limited. Our objectives were to determine whether LiDAR-derived variables could be used to accurately describe single-species distributions and community characteristics of spiders in remote forested and mountainous terrain. We collected over 5300 spiders across multiple transects in the Bavarian National Park (Germany) using pitfall traps. We examined spider community characteristics (species richness, the Shannon index, the Simpson index, community composition, mean body size, and abundance) and single-species distribution and abundance with LiDAR variables and ground-based measurements. We used the R2 and partial R2 provided by variance partitioning to evaluate the predictive power of LiDAR-derived variables compared to ground measurements for each of the community characteristics. The total adjusted R2 for species richness, the Shannon index, community species composition, and body size had a range of 25-57%. LiDAR variables and ground measurements both contributed >80% to the total predictive power. For species composition, the explained variance was approximately 32%, which was significantly greater than expected by chance. The predictive power of LiDAR-derived variables was comparable or superior to that of the ground-based variables for examinations of single-species distributions, and it explained up to 55% of the variance. The predictability of species distributions was higher for species that had strong associations with shade in open-forest habitats, and this niche position has been well documented across the European continent for spider species. The similar statistical performance between LiDAR and ground-based measures at our field sites indicated that deriving spider community and species distribution information using LiDAR data can provide not only high predictive power at

  10. Comprehensive Utilization of Temporal and Spatial Domain Outlier Detection Methods for Mobile Terrestrial LiDAR Data

    OpenAIRE

    Baoxin Hu; Jian-guo Wang; Michael Leslar

    2011-01-01

    Terrestrial LiDAR provides many disciplines with an effective and efficient means of producing realistic three-dimensional models of real world objects. With the advent of mobile terrestrial LiDAR, this ability has been expanded to include the rapid collection of three-dimensional models of large urban scenes. For all its usefulness, it does have drawbacks. One of the major problems faced by the LiDAR industry today is the automatic removal of outlying data points from LiDAR point clouds. Thi...

  11. Flow Characteristics of Tidewater Glaciers in Greenland and Alaska using Ground-Based LiDAR

    Science.gov (United States)

    Finnegan, D. C.; Stearns, L. A.; Hamilton, G. S.; O'Neel, S.

    2010-12-01

    LiDAR scanning systems have been employed to characterize and quantify multi-temporal glacier and ice sheet changes for nearly three decades. Until recently, LiDAR scanning systems were limited to airborne and space-based platforms which come at a significant cost to deploy and are limited in spatial and temporal sampling capabilities necessary to compare with in-situ field measurements. Portable ground-based LiDAR scanning systems are now being used as a glaciological tool. We discuss research efforts to employ ground-based near-infrared LiDAR systems at two differing tidewater glacier systems in the spring of 2009; Helheim Glacier in southeast Greenland and Columbia Glacier in southeast Alaska. Preliminary results allow us to characterize short term displacement rates and detailed observations of calving processes. These results highlight the operational limitations and capabilities of commercially available LiDAR systems, and allow us to identify optimal operating characteristics for monitoring small to large-scale tidewater glaciers in near real-time. Furthermore, by identifying the operational limitations of these sensors it allows for optimal design characteristics of new sensors necessary to meet ground-based calibration and validation requirements of ongoing scientific missions.

  12. The Extraction of Vegetation Points from LiDAR Using 3D Fractal Dimension Analyses

    Directory of Open Access Journals (Sweden)

    Haiquan Yang

    2015-08-01

    Full Text Available Light Detection and Ranging (LiDAR, a high-precision technique used for acquiring three-dimensional (3D surface information, is widely used to study surface vegetation information. Moreover, the extraction of a vegetation point set from the LiDAR point cloud is a basic starting-point for vegetation information analysis, and an important part of its further processing. To extract the vegetation point set completely and to describe the different spatial morphological characteristics of various features in a LiDAR point cloud, we have used 3D fractal dimensions. We discovered that every feature has its own distinctive 3D fractal dimension interval. Based on the 3D fractal dimensions of tall trees, we propose a new method for the extraction of vegetation using airborne LiDAR. According to this method, target features can be distinguished based on their morphological characteristics. The non-ground points acquired by filtering are processed by region growing segmentation and the morphological characteristics are evaluated by 3D fractal dimensions to determine the features required for the determination of the point set for tall trees. Avon, New York, USA was selected as the study area to test the method and the result proves the method’s efficiency. Thus, this approach is feasible. Additionally, the method uses the 3D coordinate properties of the LiDAR point cloud and does not require additional information, such as return intensity, giving it a larger scope of application.

  13. Development of LiDAR measurements for the German offshore test site

    Science.gov (United States)

    Rettenmeier, A.; Kühn, M.; Wächter, M.; Rahm, S.; Mellinghoff, H.; Siegmeier, B.; Reeder, L.

    2008-05-01

    The paper introduces the content of the recently started joint research project 'Development of LiDAR measurements for the German Offshore Test Site' which has the objective to support other research projects at the German offshore test site 'alpha ventus'. The project has started before the erection of the offshore wind farm and one aim is to give recommendations concerning LiDAR technology useable for offshore measurement campaigns and data analysis. The work is organized in four work packages. The work package LiDAR technology deals with the specification, acquisition and calibration of a commercial LiDAR system for the measurement campaigns. Power curve measurements are dedicated to power curve assessment with ground-based LiDAR using standard statistical methods. Additionally, it deals with the development of new methods for the measurement of non-steady short-term power curves. Wind field research aims at the development of wake loading simulation methods of wind turbines and the exploration of loading control strategies and nacelle-based wind field measurement techniques. Finally, dissemination of results to the industry takes place in work package Technology transfer.

  14. Los rostros de Ana: Tres comentarios sobre Darío Morales

    Directory of Open Access Journals (Sweden)

    Paul Marcelo Velázquez Sabogal

    2016-03-01

    Full Text Available El presente escrito es una aproximación a la obra del artista colombiano Darío Morales desde la perspectiva dialéctica “vida-muerte”, alentada por el acontecimiento de lo ambiguo y sus implicaciones en la deconstrucción de una corporeidad estable regida por parámetros sociales, jurídicos y biológicos que desembocan en la caracterización de un “otro” en el cual se encuentran figuras como el anormal, el incorregible, el monstruo. Desde ellos pretendo trazar un punto de vista sobre aquellos Rostros de Ana donde se manifiestan figuras como el onanista y la vampira, para desembocar en un comentario que amplíe el espectro de sentido alrededor la obra del artista cartagenero. Palabras claves Cuerpo ambiguo, vida-muerte, sagrado-profano, onanismo. Ñawekuna kai warmi Ana Sutipa: Kimsa pariai ksi runa Dario Morales Sugllapi Kai kilkai kame ñalla regcha kai tacha runa colombiano Dario Morales Kilkakasina rimangapa “ kausai- wamui” aida chingapa kaikuna Mana allilla llugsichu tukuikunamanda icharichu llanga “sug manda” Kaipe turrerreme ¡ kauancheme man aillakaska, man allilla rurasla! Kirú. Kaipi pudenchi kauanga imasami kauacheca kai warme Ana paipa ñawekuna Kai ruraikuna sutikame onanista Chasallata vampira, Kaiwa munakume Allilla intendechengapa imasame parlaku sug iacha Cartagenero. Ima suti Rimai Simi: Cuerpo ambiguo, kaugsai, muerte, sagrado - profano, onanismo. The Faces of Ana: Three Comments on Dario Morales Abstract This paper is an approach to the work of Colombian artist Dario Morales from the perspective of the dialectic of “life and death”, encouraged by the occurrence of the ambiguous and its implications for the deconstruction of a stable corporeality governed by social, legal and biological parameters that lead to the characterization of an “other”, in which figures such as the abnormal, the incorrigible, the monster are to be found. From them, I intend to plot a point of view on those faces of Ana

  15. The IsoDAR High Intensity H$_2^+$ Transport and Injection Tests

    CERN Document Server

    Alonso, Jose; Calabretta, Luciano; Campo, Daniela; Celona, Luigi; Conrad, Janet M; Day, Alexandra; Castro, Giuseppe; Labrecque, Francis; Winklehner, Daniel

    2015-01-01

    This technical report reviews the tests performed at the Best Cyclotron Systems, Inc. facility in regards to developing a cost effective ion source, beam line transport system, and acceleration system capable of high H$_2^+$ current output for the IsoDAR (Isotope Decay At Rest) experiment. We begin by outlining the requirements for the IsoDAR experiment then provide overview of the Versatile Ion Source, Low Energy Beam Transport system, spiral inflector, and cyclotron. The experimental measurements are then discussed and the results are compared with a thorough set of simulation studies. Of particular importance we note that the Versatile Ion Source (VIS) proved to be a reliable ion source capable of generating a large amount of H$_2^+$ current. The results suggest that with further upgrades, the VIS could potentially be a suitable candidate for IsoDAR. The conclusion outlines the key results from our tests and introduces the forthcoming work this technical report has motivated.

  16. LiDAR data and SAR imagery acquired by an unmanned helicopter for rapid landslide investigation

    Science.gov (United States)

    Kasai, M.; Tanaka, Y.; Yamazaki, T.

    2012-12-01

    When earthquakes or heavy rainfall hits a landslide prone area, initial actions require estimation of the size of damage to people and infrastructure. This includes identifying the number and size of newly collapsed or expanded landslides, and appraising subsequent risks from remobilization of landslides and debris materials. In inapproachable areas, the UAV (Unmanned Aerial Vehicles) is likely to be of greatest use. In addition, repeat monitoring of sites after the event is a way of utilizing UAVs, particularly in terms of cost and convenience. In this study, LiDAR (SkEyesBox MP-1) data and SAR (Nano SAR) imagery, acquired over 0.5 km2 landslide prone area, are presented to assess the practicability of using unmanned helicopters (in this case a 10 year old YAMAHA RMAX G1) in these situations. LiDAR data was taken in July 2012, when tree foliage covered the ground surface. However, imagery was of sufficient quality to identify and measure landslide features. Nevertheless, LiDAR data obtained by a manned helicopter in the same area in August 2008 was more detailed, reflecting the function of the LiDAR scanner. On the other hand, 2 m resolution Nano SAR imagery produced reasonable results to elucidate hillslope condition. A quick method for data processing without loss of image quality was also investigated. In conclusion, the LiDAR scanner and UAV employed here could be used to plan immediate remedial activity of the area, before LiDAR measurement with a manned helicopter can be organized. SAR imagery from UAV is also available for this initial activity, and can be further applied to long term monitoring.

  17. Detailed Hydrographic Feature Extraction from High-Resolution LiDAR Data

    Energy Technology Data Exchange (ETDEWEB)

    Danny L. Anderson

    2012-05-01

    Detailed hydrographic feature extraction from high-resolution light detection and ranging (LiDAR) data is investigated. Methods for quantitatively evaluating and comparing such extractions are presented, including the use of sinuosity and longitudinal root-mean-square-error (LRMSE). These metrics are then used to quantitatively compare stream networks in two studies. The first study examines the effect of raster cell size on watershed boundaries and stream networks delineated from LiDAR-derived digital elevation models (DEMs). The study confirmed that, with the greatly increased resolution of LiDAR data, smaller cell sizes generally yielded better stream network delineations, based on sinuosity and LRMSE. The second study demonstrates a new method of delineating a stream directly from LiDAR point clouds, without the intermediate step of deriving a DEM. Direct use of LiDAR point clouds could improve efficiency and accuracy of hydrographic feature extractions. The direct delineation method developed herein and termed “mDn”, is an extension of the D8 method that has been used for several decades with gridded raster data. The method divides the region around a starting point into sectors, using the LiDAR data points within each sector to determine an average slope, and selecting the sector with the greatest downward slope to determine the direction of flow. An mDn delineation was compared with a traditional grid-based delineation, using TauDEM, and other readily available, common stream data sets. Although, the TauDEM delineation yielded a sinuosity that more closely matches the reference, the mDn delineation yielded a sinuosity that was higher than either the TauDEM method or the existing published stream delineations. Furthermore, stream delineation using the mDn method yielded the smallest LRMSE.

  18. Detection of large above ground biomass variability in lowland forest ecosystems by airborne LiDAR

    Directory of Open Access Journals (Sweden)

    J. Jubanski

    2012-08-01

    Full Text Available Quantification of tropical forest Above Ground Biomass (AGB over large areas as input for Reduced Emissions from Deforestation and forest Degradation (REDD+ projects and climate change models is challenging. This is the first study which attempts to estimate AGB and its variability across large areas of tropical lowland forests in Central Kalimantan (Indonesia through correlating airborne Light Detection and Ranging (LiDAR to forest inventory data. Two LiDAR height metrics were analysed and regression models could be improved through the use of LiDAR point densities as input (R2 = 0.88; n = 52. Surveying with a LiDAR point density per square meter of 2–4 resulted in the best cost-benefit ratio. We estimated AGB for 600 km of LiDAR tracks and showed that there exists a considerable variability of up to 140% within the same forest type due to varying environmental conditions. Impact from logging operations and the associated AGB losses dating back more than 10 yr could be assessed by LiDAR but not by multispectral satellite imagery. Comparison with a Landsat classification for a 1 million ha study area where AGB values were based on site specific field inventory data, regional literature estimates, and default values by the Intergovernmental Panel on Climate Change (IPCC showed an overestimation of 46%, 102%, and 137%, respectively. The results show that AGB overestimation may lead to wrong GHG emission estimates due to deforestation in climate models. For REDD+ projects this leads to inaccurate carbon stock estimates and consequently to significantly wrong REDD+ based compensation payments.

  19. Optimisation of LiDAR derived terrain models for river flow modelling

    Directory of Open Access Journals (Sweden)

    G. Mandlburger

    2008-12-01

    Full Text Available Airborne LiDAR (Light Detection And Ranging combines cost efficiency, high degree of automation, high point density of typically 1–10 points per m2 and height accuracy of better than ±15 cm. For all these reasons LiDAR is particularly suitable for deriving precise Digital Terrain Models (DTM as geometric basis for hydrodynamic-numerical (HN simulations. The application of LiDAR for river flow modelling requires a series of preprocessing steps. Terrain points have to be filtered and merged with river bed data, e.g. from echo sounding. Then, a smooth Digital Terrain Model of the Watercourse (DTM-W needs to be derived, preferably considering the random measurement error during surface interpolation. In a subsequent step, a hydraulic computation mesh has to be constructed. Hydraulic simulation software is often restricted to a limited number of nodes and elements, thus, data reduction and data conditioning of the high resolution LiDAR DTM-W becomes necessary. We will present a DTM thinning approach based on adaptive TIN refinement which allows a very effective compression of the point data (more than 95% in flood plains and up to 90% in steep areas while preserving the most relevant topographic features (height tolerance ±20 cm. Traditional hydraulic mesh generators focus primarily on physical aspects of the computation grid like aspect ratio, expansion ratio and angle criterion. They often neglect the detailed shape of the topography as provided by LiDAR data. In contrast, our approach considers both the high geometric resolution of the LiDAR data and additional mesh quality parameters. It will be shown that the modelling results (flood extents, flow velocities, etc. can vary remarkably by the availability of surface details. Thus, the inclusion of such geometric details in the hydraulic computation meshes will gain importance for river flow modelling in the future.

  20. The Introduction of a Domestic Airborne LiDAR System SW-LiDAR%国产SW-LiDAR系统的简介

    Institute of Scientific and Technical Information of China (English)

    李志杰; 施昆; 关艳玲; 蒋凤保

    2013-01-01

    This paper introduced the structure, characteristics of a domestic airborne LiDAR systems SW-LiDAR and USES. This paper also provided highlights of inertial navigation principle, the principle of differential GPS and conformation equation, which is integrate theory. The workflow was introduced. Finally, the development trend of the system were prospected.%本文介绍国产机载SW-LiDAR系统的构成、特点和用途。重点阐述了该系统的三个集成原理:惯性导航原理、差分GPS原理和构象方程。介绍了该系统的工作流程。最后展望了该系统的应用前景。

  1. 'Dar Kenn Ghal Sahhtek'--an eating disorder and obesity service in Malta.

    Science.gov (United States)

    Aquilina, Francesca Falzon; Grech, Anton; Zerafa, Darleen; Agius, Mark; Voon, Valerie

    2015-09-01

    This paper will describe the incidence of eating disorders, with particular focus on obesity and binge eating, within the Island of Malta. The development of and 'Dar Kenn Ghal Sahhtek', the first centre for eating disorders in Malta will then be recounted, and the effective therapeutic interventions provided in it will be described. One important function of this unit is the treatment of excessive obesity. Some epidemiological data on the Obese Patients in DKS, relating to the incidence of Binge Eating Disorder in the DKS patient group will be given. This data was collected during a collaboritive research project between the Psychiatry Department of Cambridge University and 'Dar Kenn Ghal Sahhtek'.

  2. Diagnóstico Territorial Integral del municipio de Ciudad Darío

    OpenAIRE

    2010-01-01

    EN ESTE ARTÍCULO SE PRESENTA EL “DIAGNÓSTICO TERRITORIAL INTEGRAL de Ciudad Darío” realizado como trabajo de fin de curso de la Maestría en Desarrollo Rural de la Universidad Centroamericana. Este estudio ha buscado contribuir a la formulación de propuestas de intervención de los actores sociales del municipio de Ciudad Darío sobre los procesos estratégicos de desarrollo del territorio. Se realizó unazonificación integral del municipio, identificándose cuatro zonas: una zona alta, campesina d...

  3. Direct injection into the IsoDAR Cyclotron using a RFQ

    Science.gov (United States)

    Axani, Spencer; IsoDAR Collaboration

    2015-04-01

    Beginning in the 1970s, the use of Radio Frequency Quadrupoles (RFQs) has been pervasive in linear accelerators in order to accelerate, bunch, and separate ion species. Current research suggests this may be an ideal way to inject a low energy H2+ beam axially into a cyclotron. The IsoDAR (Isotope Decay At Rest) experiment aims to implement this injection system in order to achieve higher Low Energy Beam Transport (LEBT) efficiencies and ultimately construct a novel compact neutrino factory to test the hypothesis of sterile neutrinos. This talk will focus on the research and development needed to implement a RFQ into the IsoDAR experiment.

  4. Not seeing the forest for the points: Novel LiDAR metrics elucidate forest structure and increase LiDAR usability by managers

    OpenAIRE

    Kramer, Heather Anuhea

    2016-01-01

    Forest and fire ecology have long utilized remote sensing datasets to learn more about landscapes. Advances in gps spatial accuracy, GIS software capabilities, computing power, and remote sensing technology and software, as well as increases in the spatial and temporal resolution of remote sensing products, have made remote sensing a critical component of forest and fire ecology. Aerial light detection and ranging (LiDAR) is a fast-growing active remote-sensing technology that can be mined fo...

  5. Qué es el acceso abierto

    OpenAIRE

    García León, Mª Dolores

    2012-01-01

    Semana del acceso abierto 2012. Universidad Politécnica de Valencia Taller sobre el acceso abierto impartido en las actividades organizadas por la biblioteca dentro de la semana del acceso abierto 2012 García León, MD. (2012). Qué es el acceso abierto. http://riunet.upv.es/handle/10251/17581.

  6. ¿Qué es un indicador de derechos humanos y cómo se utiliza?

    OpenAIRE

    García Cívico, Jesús

    2011-01-01

    El objetivo de este trabajo es dar una visión general de la investigación de derechos humanos con indicadores. Se analizan los conceptos fundamentales, qué es un indicador, qué lugar ocupa en el ámbito jurídico y sobre todo qué son los indicadores de derechos humanos. Se sitúa históricamente la investigación de derechos humanos con indicadores y se resumen los intentos más significativos de trazar un “mapa del mundo” en relación con su implementación, grado de cumplimiento o violaciones. Se r...

  7. Developments for the IsoDAR@KamLAND and DAE{\\delta}ALUS Decay-At-Rest Neutrino Experiments

    CERN Document Server

    ,

    2016-01-01

    Configurations of the IsoDAR and DAE{\\delta}ALUS decay-at-rest neutrino experiments are described. Injector and cyclotron developments aimed at substantial increases in beam current are discussed. The IsoDAR layout and target are described, and this experiment is compared to other programs searching for sterile neutrinos.

  8. Remote Sensing of Sonoran Desert Vegetation Structure and Phenology with Ground-Based LiDAR

    Directory of Open Access Journals (Sweden)

    Joel B. Sankey

    2014-12-01

    Full Text Available Long-term vegetation monitoring efforts have become increasingly important for understanding ecosystem response to global change. Many traditional methods for monitoring can be infrequent and limited in scope. Ground-based LiDAR is one remote sensing method that offers a clear advancement to monitor vegetation dynamics at high spatial and temporal resolution. We determined the effectiveness of LiDAR to detect intra-annual variability in vegetation structure at a long-term Sonoran Desert monitoring plot dominated by cacti, deciduous and evergreen shrubs. Monthly repeat LiDAR scans of perennial plant canopies over the course of one year had high precision. LiDAR measurements of canopy height and area were accurate with respect to total station survey measurements of individual plants. We found an increase in the number of LiDAR vegetation returns following the wet North American Monsoon season. This intra-annual variability in vegetation structure detected by LiDAR was attributable to a drought deciduous shrub Ambrosia deltoidea, whereas the evergreen shrub Larrea tridentata and cactus Opuntia engelmannii had low variability. Benefits of using LiDAR over traditional methods to census desert plants are more rapid, consistent, and cost-effective data acquisition in a high-resolution, 3-dimensional context. We conclude that repeat LiDAR measurements can be an effective method for documenting ecosystem response to desert climatology and drought over short time intervals and at detailed-local spatial scale.

  9. The use of airborne LiDAR data for the analysis of debris flow events in Switzerland

    Directory of Open Access Journals (Sweden)

    C. Scheidl

    2008-10-01

    Full Text Available A methodology of magnitude estimates for debris flow events is described using airborne LiDAR data. Light Detection And Ranging (LiDAR is a widely used technology to generate digital elevation information. LiDAR data in alpine regions can be obtained by several commercial companies where the automated filtering process is proprietary and varies from companies to companies. This study describes the analysis of geomorphologic changes using digital terrain models derived from commercial LiDAR data. The estimation of the deposition volumes is based on two digital terrain models covering the same area but differing in their time of survey. In this study two surveyed deposition areas of debris flows, located in the canton of Berne, Switzerland, were chosen as test cases. We discuss different grid interpolating techniques, other preliminary work and the accuracy of the used LiDAR data and volume estimates.

  10. A DATA DRIVEN METHOD FOR BUILDING RECONSTRUCTION FROM LiDAR POINT CLOUDS

    Directory of Open Access Journals (Sweden)

    M. Sajadian

    2014-10-01

    Full Text Available Airborne laser scanning, commonly referred to as LiDAR, is a superior technology for three-dimensional data acquisition from Earth's surface with high speed and density. Building reconstruction is one of the main applications of LiDAR system which is considered in this study. For a 3D reconstruction of the buildings, the buildings points should be first separated from the other points such as; ground and vegetation. In this paper, a multi-agent strategy has been proposed for simultaneous extraction and segmentation of buildings from LiDAR point clouds. Height values, number of returned pulse, length of triangles, direction of normal vectors, and area are five criteria which have been utilized in this step. Next, the building edge points are detected using a new method named "Grid Erosion". A RANSAC based technique has been employed for edge line extraction. Regularization constraints are performed to achieve the final lines. Finally, by modelling of the roofs and walls, 3D building model is reconstructed. The results indicate that the proposed method could successfully extract the building from LiDAR data and generate the building models automatically. A qualitative and quantitative assessment of the proposed method is then provided.

  11. Engineering monitoring of rockfall hazards along transportation corridors: using mobile terrestrial LiDAR

    Directory of Open Access Journals (Sweden)

    M. Lato

    2009-06-01

    Full Text Available Geotechnical hazards along linear transportation corridors are challenging to identify and often require constant monitoring. Inspecting corridors using traditional, manual methods requires the engineer to be unnecessarily exposed to the hazard. It also requires closure of the corridor to ensure safety of the worker from passing vehicles. This paper identifies the use of mobile terrestrial LiDAR data as a compliment to traditional field methods. Mobile terrestrial LiDAR is an emerging remote data collection technique capable of generating accurate fully three-dimensional virtual models while driving at speeds up to 100 km/h. Data is collected from a truck that causes no delays to active traffic nor does it impede corridor use. These resultant georeferenced data can be used for geomechanical structural feature identification and kinematic analysis, rockfall path identification and differential monitoring of rock movement or failure over time. Comparisons between mobile terrestrial and static LiDAR data collection and analysis are presented. As well, detailed discussions on workflow procedures for possible implementation are discussed. Future use of mobile terrestrial LiDAR data for corridor analysis will focus on repeated surveys and developing dynamic four-dimensional models, higher resolution data collection. As well, computationally advanced, spatially accurate, geomechanically controlled three-dimensional rockfall simulations should be investigated.

  12. Geospatial revolution and remote sensing LiDAR in Mesoamerican archaeology.

    Science.gov (United States)

    Chase, Arlen F; Chase, Diane Z; Fisher, Christopher T; Leisz, Stephen J; Weishampel, John F

    2012-08-07

    The application of light detection and ranging (LiDAR), a laser-based remote-sensing technology that is capable of penetrating overlying vegetation and forest canopies, is generating a fundamental shift in Mesoamerican archaeology and has the potential to transform research in forested areas world-wide. Much as radiocarbon dating that half a century ago moved archaeology forward by grounding archaeological remains in time, LiDAR is proving to be a catalyst for an improved spatial understanding of the past. With LiDAR, ancient societies can be contextualized within a fully defined landscape. Interpretations about the scale and organization of densely forested sites no longer are constrained by sample size, as they were when mapping required laborious on-ground survey. The ability to articulate ancient landscapes fully permits a better understanding of the complexity of ancient Mesoamerican urbanism and also aids in modern conservation efforts. The importance of this geospatial innovation is demonstrated with newly acquired LiDAR data from the archaeological sites of Caracol, Cayo, Belize and Angamuco, Michoacán, Mexico. These data illustrate the potential of technology to act as a catalytic enabler of rapid transformational change in archaeological research and interpretation and also underscore the value of on-the-ground archaeological investigation in validating and contextualizing results.

  13. 2009 U.S. Geological Survey (USGS) Topographic LiDAR: Androscoggin County, Maine

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — USGS Contract Number: G10PC00026 USGS Task Order: G10PD01737 LiDAR was collected at a 1.0 points per square meter (1.0m GSD) for the county of Androscoggin, Maine...

  14. Point Density Effects on Digital Elevation Models Generated from LiDAR Data

    Science.gov (United States)

    2009-06-01

    Weighted ( IDW ) and spline-based and geostatistic such as Kriging. Inverse Distance Weighted ( IDW ) assumes that each point has a local influence...the IDW method performs well if sampling data density is high, even for complex terrain (Liu, 2008). D. PREVIOUS DATA ANALYSIS RESULTS LiDAR data

  15. Habitat Classification of Temperate Marine Macroalgal Communities Using Bathymetric LiDAR

    Directory of Open Access Journals (Sweden)

    Richard Zavalas

    2014-03-01

    Full Text Available Here, we evaluated the potential of using bathymetric Light Detection and Ranging (LiDAR to characterise shallow water (<30 m benthic habitats of high energy subtidal coastal environments. Habitat classification, quantifying benthic substrata and macroalgal communities, was achieved in this study with the application of LiDAR and underwater video groundtruth data using automated classification techniques. Bathymetry and reflectance datasets were used to produce secondary terrain derivative surfaces (e.g., rugosity, aspect that were assumed to influence benthic patterns observed. An automated decision tree classification approach using the Quick Unbiased Efficient Statistical Tree (QUEST was applied to produce substrata, biological and canopy structure habitat maps of the study area. Error assessment indicated that habitat maps produced were primarily accurate (>70%, with varying results for the classification of individual habitat classes; for instance, producer accuracy for mixed brown algae and sediment substrata, was 74% and 93%, respectively. LiDAR was also successful for differentiating canopy structure of macroalgae communities (i.e., canopy structure classification, such as canopy forming kelp versus erect fine branching algae. In conclusion, habitat characterisation using bathymetric LiDAR provides a unique potential to collect baseline information about biological assemblages and, hence, potential reef connectivity over large areas beyond the range of direct observation. This research contributes a new perspective for assessing the structure of subtidal coastal ecosystems, providing a novel tool for the research and management of such highly dynamic marine environments.

  16. LiDAR Relative Reflectivity Surface (2011) for Coral Bay, St. John

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a LiDAR (Light Detection & Ranging) 0.3x0.3 meter resolution relative seafloor reflectivity surface for Coral Bay, St. John in the U.S....

  17. 2010 U.S. Geological Survey (USGS) Topographic LiDAR: Mobile Bay, AL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — USGS Contract: G10PC00026 Task Order Number: G10PD00578 LiDAR was collected at a nominal pulse spacing of 2.0 meters for a 700 square mile area to the east of Mobile...

  18. Genetics and Human Agency: Comment on Dar-Nimrod and Heine (2011)

    Science.gov (United States)

    Turkheimer, Eric

    2011-01-01

    Dar-Nimrod and Heine (2011) decried genetic essentialism without denying the importance of genetics in the genesis of human behavior, and although I agree on both counts, a deeper issue remains unaddressed: how should we adjust our cognitions about our own behavior in light of genetic influence, or is it perhaps not necessary to take genetics into…

  19. Dynamic displacement estimation by fusing LDV and LiDAR measurements via smoothing based Kalman filtering

    Science.gov (United States)

    Kim, Kiyoung; Sohn, Hoon

    2017-01-01

    This paper presents a smoothing based Kalman filter to estimate dynamic displacement in real-time by fusing the velocity measured from a laser Doppler vibrometer (LDV) and the displacement from a light detection and ranging (LiDAR). LiDAR can measure displacement based on the time-of-flight information or the phase-shift of the laser beam reflected off form a target surface, but it typically has a high noise level and a low sampling rate. On the other hand, LDV primarily measures out-of-plane velocity of a moving target, and displacement is estimated by numerical integration of the measured velocity. Here, the displacement estimated by LDV suffers from integration error although LDV can achieve a lower noise level and a much higher sampling rate than LiDAR. The proposed data fusion technique estimates high-precision and high-sampling rate displacement by taking advantage of both LiDAR and LDV measurements and overcomes their limitations by adopting a real-time smoothing based Kalman filter. To verify the performance of the proposed dynamic displacement estimation technique, a series of lab-scale tests are conducted under various loading conditions.

  20. LiDAR Relative Reflectivity Surface (2011) for Fish Bay, St. John

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a LiDAR (Light Detection & Ranging) 0.3x0.3 meter resolution relative seafloor reflectivity surface for Fish Bay, St. John in the U.S....

  1. Line-Based Registration of Panoramic Images and LiDAR Point Clouds for Mobile Mapping.

    Science.gov (United States)

    Cui, Tingting; Ji, Shunping; Shan, Jie; Gong, Jianya; Liu, Kejian

    2016-12-31

    For multi-sensor integrated systems, such as the mobile mapping system (MMS), data fusion at sensor-level, i.e., the 2D-3D registration between an optical camera and LiDAR, is a prerequisite for higher level fusion and further applications. This paper proposes a line-based registration method for panoramic images and a LiDAR point cloud collected by a MMS. We first introduce the system configuration and specification, including the coordinate systems of the MMS, the 3D LiDAR scanners, and the two panoramic camera models. We then establish the line-based transformation model for the panoramic camera. Finally, the proposed registration method is evaluated for two types of camera models by visual inspection and quantitative comparison. The results demonstrate that the line-based registration method can significantly improve the alignment of the panoramic image and the LiDAR datasets under either the ideal spherical or the rigorous panoramic camera model, with the latter being more reliable.

  2. Shape Detection from Raw LiDAR Data with Subspace Modeling.

    Science.gov (United States)

    Wang, Jun; Xu, Kevin Kai

    2016-08-31

    LiDAR scanning has become a prevalent technique for digitalizing large-scale outdoor scenes. However, the raw LiDAR data often contain imperfections, e.g., missing large regions, anisotropy of sampling density, and contamination of noise and outliers, which are the major obstacles that hinder its more ambitious and higher level applications in digital city modeling. Observing that 3D urban scenes can be locally described with several low dimensional subspaces, we propose to locally classify the neighborhoods of the scans to model the substructures of the scenes. The key enabler is the adaptive kernel-scale scoring, filtering and clustering of substructures, making it possible to recover the local structures at all points simultaneously, even in the presence of severe data imperfections. Integrating the local analyses leads to robust shape detection from raw LiDAR data. On this basis, we develop several urban scene applications and verify them on a number of LiDAR scans with various complexities and styles, which demonstrates the effectiveness and robustness of our methods.

  3. Errors in LiDAR-derived shrub height and crown area on sloped terrain

    Science.gov (United States)

    This study developed and tested four methodologies for determining shrub height measurements with LiDAR data in a semiarid shrub-steppe in southwestern Idaho, USA. Unique to this study was the focus of sagebrush height measurements on sloped terrain. The study also developed one of the first metho...

  4. 2002 Maryland Department of Natural Resources LiDAR: Worcester County

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Light Detection and Ranging (LiDAR) is a method of locating objects on the ground using aerial-borne equipment. It is similar to RADAR or SONAR in that the two-way...

  5. Implications of sensor configuration and topography on vertical plant profiles derived from terrestrial LiDAR

    NARCIS (Netherlands)

    Calders, K.; Armston, J.; Newnham, G.; Herold, M.; Goodwin, N.

    2014-01-01

    The vertical distribution of plant constituents is a key parameter to describe vegetation structure and influences several processes, such as radiation interception, growth and habitat. Terrestrial laser scanning (TLS), also referred to as terrestrial LiDAR, has the potential to measure the canopy s

  6. Skeleton-based botanic tree diameter estimation from dense LiDAR data

    NARCIS (Netherlands)

    Bucksch, A.; Lindenbergh, R.; Mementi, M.; Raman, M.Z.

    2009-01-01

    New airborne LiDAR (Light Detection and Ranging) measurement systems, like the FLI-MAP 400 System, make it possible to obtain high density data containing far more information about single objects, like trees, than traditional airborne laser systems. Therefore, it becomes feasible to analyze geometr

  7. Fast and nondestructive method for leaf level chlorophyll estimation using hyperspectral LiDAR

    NARCIS (Netherlands)

    Nevalainen, O.; Hakala, T.; Suomalainen, J.M.; Mäkipää, R.; Peltoniemi, M.; Krooks, A.; Kaasalainen, S.

    2014-01-01

    We propose an empirical method for nondestructive estimation of chlorophyll in tree canopies. The first prototype of a full waveform hyperspectral LiDAR instrument has been developed by the Finnish Geodetic Institute (FGI). The instrument efficiently combines the benefits of passive and active remot

  8. Object-Based Classification of Abandoned Logging Roads under Heavy Canopy Using LiDAR

    Directory of Open Access Journals (Sweden)

    Jason Sherba

    2014-05-01

    Full Text Available LiDAR-derived slope models may be used to detect abandoned logging roads in steep forested terrain. An object-based classification approach of abandoned logging road detection was employed in this study. First, a slope model of the study site in Marin County, California was created from a LiDAR derived DEM. Multiresolution segmentation was applied to the slope model and road seed objects were iteratively grown into candidate objects. A road classification accuracy of 86% was achieved using this fully automated procedure and post processing increased this accuracy to 90%. In order to assess the sensitivity of the road classification to LiDAR ground point spacing, the LiDAR ground point cloud was repeatedly thinned by a fraction of 0.5 and the classification procedure was reapplied. The producer’s accuracy of the road classification declined from 79% with a ground point spacing of 0.91 to below 50% with a ground point spacing of 2, indicating the importance of high point density for accurate classification of abandoned logging roads.

  9. Biology and management of fish stocks in Bahir Dar Gulf, Lake Tana, Ethiopia.

    NARCIS (Netherlands)

    Wudneh, T.

    1998-01-01

    The biology of the fish stocks of the major species in the Bahir Dar Gulf of Lake Tana, the largest lake in Ethiopia, has been studied based on data collected during August 1990 to September 1993. The distribution, reproduction patterns, growth and mortality dynamics and gillnet selectivity of these

  10. Registration of optical imagery and LiDAR data using an inherent geometrical constraint.

    Science.gov (United States)

    Zhang, Wuming; Zhao, Jing; Chen, Mei; Chen, Yiming; Yan, Kai; Li, Linyuan; Qi, Jianbo; Wang, Xiaoyan; Luo, Jinghui; Chu, Qing

    2015-03-23

    A novel method for registering imagery with Light Detection And Ranging (LiDAR) data is proposed. It is based on the phenomenon that the back-projection of LiDAR point cloud of an object should be located within the object boundary in the image. Using this inherent geometrical constraint, the registration parameters computation of both data sets only requires LiDAR point clouds of several objects and their corresponding boundaries in the image. The proposed registration method comprises of four steps: point clouds extraction, boundary extraction, back-projection computation and registration parameters computation. There are not any limitations on the geometrical and spectral properties of the object. So it is suitable not only for structured scenes with man-made objects but also for natural scenes. Moreover, the proposed method based on the inherent geometrical constraint can register two data sets derived from different parts of an object. It can be used to co-register TLS (Terrestrial Laser Scanning) LiDAR point cloud and UAV (Unmanned aerial vehicle) image, which are obtaining more attention in the forest survey application. Using initial registration parameters comparable to POS (position and orientation system) accuracy, the performed experiments validated the feasibility of the proposed registration method.

  11. A comparison of two open source LiDAR surface classification algorithms

    Science.gov (United States)

    With the progression of LiDAR (Light Detection and Ranging) towards a mainstream resource management tool, it has become necessary to understand how best to process and analyze the data. While most ground surface identification algorithms remain proprietary and have high purchase costs; a few are op...

  12. 2014 U.S. Geological Survey CMGP LiDAR: Post Sandy (Pennsylvania)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fugro EarthData, Inc. (Fugro) was tasked by the U.S. Geological Survey (USGS) to plan, acquire, process, and produce derivative products of LiDAR data at a nominal...

  13. Urban Classification Techniques Using the Fusion of LiDAR and Spectral Data

    Science.gov (United States)

    2012-09-01

    probably be made to improve final results. 14. SUBJECT TERMS Fusion, Multi-Source, Hyperspectral , Multispectral, LiDAR, Urban Classification ...Landsat Thematic Mapper for 1986, 1991, 1998, and 2002. A hybrid supervised- unsupervised classification technique was developed that clustered the...The multispectral spectral resolution is not as high as that of a hyperspectral sensor. Using hyperspectral data, finer classifications could

  14. Airborne hyperspectral and LiDAR data integration for weed detection

    Science.gov (United States)

    Tamás, János; Lehoczky, Éva; Fehér, János; Fórián, Tünde; Nagy, Attila; Bozsik, Éva; Gálya, Bernadett; Riczu, Péter

    2014-05-01

    Agriculture uses 70% of global available fresh water. However, ca. 50-70% of water used by cultivated plants, the rest of water transpirated by the weeds. Thus, to define the distribution of weeds is very important in precision agriculture and horticulture as well. To survey weeds on larger fields by traditional methods is often time consuming. Remote sensing instruments are useful to detect weeds in larger area. In our investigation a 3D airborne laser scanner (RIEGL LMS-Q680i) was used in agricultural field near Sopron to scouting weeds. Beside the airborne LiDAR, hyperspectral imaging system (AISA DUAL) and air photos helped to investigate weed coverage. The LiDAR survey was carried out at early April, 2012, before sprouting of cultivated plants. Thus, there could be detected emerging of weeds and direction of cultivation. However airborne LiDAR system was ideal to detect weeds, identification of weeds at species level was infeasible. Higher point density LiDAR - Terrestrial laser scanning - systems are appropriate to distinguish weed species. Based on the results, laser scanner is an effective tool to scouting of weeds. Appropriate weed detection and mapping systems could contribute to elaborate water and herbicide saving management technique. This publication was supported by the OTKA project K 105789.

  15. Line-Based Registration of Panoramic Images and LiDAR Point Clouds for Mobile Mapping

    Directory of Open Access Journals (Sweden)

    Tingting Cui

    2016-12-01

    Full Text Available For multi-sensor integrated systems, such as the mobile mapping system (MMS, data fusion at sensor-level, i.e., the 2D-3D registration between an optical camera and LiDAR, is a prerequisite for higher level fusion and further applications. This paper proposes a line-based registration method for panoramic images and a LiDAR point cloud collected by a MMS. We first introduce the system configuration and specification, including the coordinate systems of the MMS, the 3D LiDAR scanners, and the two panoramic camera models. We then establish the line-based transformation model for the panoramic camera. Finally, the proposed registration method is evaluated for two types of camera models by visual inspection and quantitative comparison. The results demonstrate that the line-based registration method can significantly improve the alignment of the panoramic image and the LiDAR datasets under either the ideal spherical or the rigorous panoramic camera model, with the latter being more reliable.

  16. 2010 U.S. Geological Survey (USGS) Topographic LiDAR: Mobile Bay, AL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — USGS Contract: G10PC00026 Task Order Number: G10PD00578 LiDAR was collected at a nominal pulse spacing of 2.0 meters for a 700 square mile area to the east of...

  17. 2012-2013 U.S. Geological Survey LiDAR: Territory of Guam

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Territory of Guam, LiDAR Task G11PD01189 This task order is for production of surface model products of The Territory of Guam. The models are produced from data...

  18. Hyperspectral and LiDAR remote sensing of fire fuels in Hawaii Volcanoes National Park.

    Science.gov (United States)

    Varga, Timothy A; Asner, Gregory P

    2008-04-01

    Alien invasive grasses threaten to transform Hawaiian ecosystems through the alteration of ecosystem dynamics, especially the creation or intensification of a fire cycle. Across sub-montane ecosystems of Hawaii Volcanoes National Park on Hawaii Island, we quantified fine fuels and fire spread potential of invasive grasses using a combination of airborne hyperspectral and light detection and ranging (LiDAR) measurements. Across a gradient from forest to savanna to shrubland, automated mixture analysis of hyperspectral data provided spatially explicit fractional cover estimates of photosynthetic vegetation, non-photosynthetic vegetation, and bare substrate and shade. Small-footprint LiDAR provided measurements of vegetation height along this gradient of ecosystems. Through the fusion of hyperspectral and LiDAR data, a new fire fuel index (FFI) was developed to model the three-dimensional volume of grass fuels. Regionally, savanna ecosystems had the highest volumes of fire fuels, averaging 20% across the ecosystem and frequently filling all of the three-dimensional space represented by each image pixel. The forest and shrubland ecosystems had lower FFI values, averaging 4.4% and 8.4%, respectively. The results indicate that the fusion of hyperspectral and LiDAR remote sensing can provide unique information on the three-dimensional properties of ecosystems, their flammability, and the potential for fire spread.

  19. Processing and accuracy of topobathymetric LiDAR data in land-water transition zones

    OpenAIRE

    M. S. Andersen; A. GERGELY; Al-Hamdani, Z.; Steinbacher, F.; Larsen, L. R.; V. B. Ernstsen

    2016-01-01

    The transition zone between land and water is difficult to map with conventional geophysical systems due to shallow water depth and often harsh environmental conditions. The emerging technology of airborne topobathymetric Light Detection And Ranging (LiDAR) is capable of providing both topographic and bathymetric elevation information, resulting in a seamless coverage of the land-water transition zone. However, there is ...

  20. 2011 U.S. Geological Survey Topographic LiDAR: Suwannee River Expansion

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — USGS Task Order No. G10PD00236 USGS Contract No. G10PC00093 The Light Detection and Ranging (LiDAR) dataset is a survey of the Suwannee River Expansion in...

  1. 2006 Federal Emergency Management Agency (FEMA) Topographic LiDAR: Cumberland and York Counties, Maine

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In the fall of 2006, Sanborn Map Company was contracted by Camp Dresser McKee, Inc (CDM) to execute a LiDAR (Light Detection and Ranging) survey campaign in the...

  2. LiDAR measurements of full scale wind turbine wake characteristics

    DEFF Research Database (Denmark)

    Hansen, Kurt Schaldemose; Larsen, Gunner Chr.; Mann, Jakob;

    2009-01-01

    Full scale wind speed measurements, recorded inside the wake of an operating 2MW/80m wind turbine,has been performed during the spring 2009, as part of the EU-TOPFARM project. Longitudinal wind speeds in wake cross sections are measured with a LiDAR system mounted in the rear of the nacelle...

  3. La convivencia no es tan obvia

    OpenAIRE

    García-Dalmás, Alicia; Universidad de la República (Uruguay)

    2015-01-01

    La promoción de una mejor convivencia a través de la generación o mejora de espacios públicos, básicamente plazas y parques, sigue siendo una de las principales propuestas con las que las políticas públicas, por lo menos en Uruguay, buscan dar respuesta a lo que identifican como “problemas sociales acuciantes”: la violencia, la inseguridad. El presente artículo toma como base una propuesta, la Estrategia por la Vida y la Convivencia, impulsada por el gobierno nacional que, entre otros aspecto...

  4. Distinguishing grass from ground using LiDAR: Techniques and applications

    Science.gov (United States)

    Pelletier, J. D.; Swetnam, T.; Papuga, S. A.; Nelson, K.; Brooks, P. D.; Harpold, A. A.; Chorover, J.

    2011-12-01

    Standard protocols exist for extracting bare-earth Digital Elevation Models (DEMs) from LiDAR point clouds that include trees and other large woody vegetation. Grasses and other herbaceous plants can also obscure the ground surface, yet methods for optimally distinguishing grass from ground to generate accurate LiDAR-based raster products for geomorphic and ecological applications are still under development. Developing such methods is important because LiDAR-based difference products (e.g. snow thickness) require accurate representations of the ground surface and because raster data for grass height and density have important applications in ecology. In this study, we developed and tested methods for constructing optimal bare-earth and grass height raster layers from LiDAR point clouds and compared the results to high-quality field-based measurements of grass height, density, and species type for nearly 1000 precisely geo-referenced locations collected during the acquisition of a >200 km^2 airborne LiDAR flight of the Valles Caldera National Preserve (New Mexico). In cases of partially bare ground (where the skewness of return heights above a plane fit to the lowest first returns is sufficiently large), a planar fit to the lowest first returns provides a good method of producing an accurate bare-earth DEM and the statistics of the first returns above that planar fit provide good estimates of the mean and variance of grass height. In areas of relatively thick grass cover, however, a fit to the lowest first returns yields a bare-earth DEM that may be a meter or more above the actual ground surface. Here we propose a method to solve this problem using field-measured correlations among the mean, variance, and skewness of grass heights. In this method, the variance and skewness of the differences between LiDAR first returns and a 10m^2 planar fit to the lowest first returns is used, together with field-based correlations of grass height statistics, to estimate the mean

  5. Building Damage Assessment after Earthquake Using Post-Event LiDAR Data

    Science.gov (United States)

    Rastiveis, H.; Eslamizade, F.; Hosseini-Zirdoo, E.

    2015-12-01

    After an earthquake, damage assessment plays an important role in leading rescue team to help people and decrease the number of mortality. Damage map is a map that demonstrates collapsed buildings with their degree of damage. With this map, finding destructive buildings can be quickly possible. In this paper, we propose an algorithm for automatic damage map generation after an earthquake using post-event LiDAR Data and pre-event vector map. The framework of the proposed approach has four main steps. To find the location of all buildings on LiDAR data, in the first step, LiDAR data and vector map are registered by using a few number of ground control points. Then, building layer, selected from vector map, are mapped on the LiDAR data and all pixels which belong to the buildings are extracted. After that, through a powerful classifier all the extracted pixels are classified into three classes of "debris", "intact building" and "unclassified". Since textural information make better difference between "debris" and "intact building" classes, different textural features are applied during the classification. After that, damage degree for each candidate building is estimated based on the relation between the numbers of pixels labelled as "debris" class to the whole building area. Calculating the damage degree for each candidate building, finally, building damage map is generated. To evaluate the ability proposed method in generating damage map, a data set from Port-au-Prince, Haiti's capital after the 2010 Haiti earthquake was used. In this case, after calculating of all buildings in the test area using the proposed method, the results were compared to the damage degree which estimated through visual interpretation of post-event satellite image. Obtained results were proved the reliability of the proposed method in damage map generation using LiDAR data.

  6. Estimating Stand Volume and Above-Ground Biomass of Urban Forests Using LiDAR

    Directory of Open Access Journals (Sweden)

    Vincenzo Giannico

    2016-04-01

    Full Text Available Assessing forest stand conditions in urban and peri-urban areas is essential to support ecosystem service planning and management, as most of the ecosystem services provided are a consequence of forest stand characteristics. However, collecting data for assessing forest stand conditions is time consuming and labor intensive. A plausible approach for addressing this issue is to establish a relationship between in situ measurements of stand characteristics and data from airborne laser scanning (LiDAR. In this study we assessed forest stand volume and above-ground biomass (AGB in a broadleaved urban forest, using a combination of LiDAR-derived metrics, which takes the form of a forest allometric model. We tested various methods for extracting proxies of basal area (BA and mean stand height (H from the LiDAR point-cloud distribution and evaluated the performance of different models in estimating forest stand volume and AGB. The best predictors for both models were the scale parameters of the Weibull distribution of all returns (except the first (proxy of BA and the 95th percentile of the distribution of all first returns (proxy of H. The R2 were 0.81 (p < 0.01 for the stand volume model and 0.77 (p < 0.01 for the AGB model with a RMSE of 23.66 m3·ha−1 (23.3% and 19.59 Mg·ha−1 (23.9%, respectively. We found that a combination of two LiDAR-derived variables (i.e., proxy of BA and proxy of H, which take the form of a forest allometric model, can be used to estimate stand volume and above-ground biomass in broadleaved urban forest areas. Our results can be compared to other studies conducted using LiDAR in broadleaved forests with similar methods.

  7. Water turbidity estimation from airborne hyperspectral imagery and full waveform bathymetric LiDAR

    Science.gov (United States)

    Pan, Z.; Glennie, C. L.; Fernandez-Diaz, J. C.

    2015-12-01

    The spatial and temporal variations in water turbidity are of great interest for the study of fluvial and coastal environments; and for predicting the performance of remote sensing systems that are used to map these. Conventional water turbidity estimates from remote sensing observations have normally been derived using near infrared reflectance. We have investigated the potential of determining water turbidity from additional remote sensing sources, namely airborne hyperspectral imagery and single wavelength bathymetric LiDAR (Light Detection and Ranging). The confluence area of the Blue and Colorado River, CO was utilized as a study area to investigate the capabilities of both airborne bathymetric LiDAR and hyperspectral imagery for water turbidity estimation. Discrete and full waveform bathymetric data were collected using Optech's Gemini (1064 nm) and Aquarius (532 nm) LiDAR sensors. Hyperspectral imagery (1.2 m pixel resolution and 72 spectral bands) was acquired using an ITRES CASI-1500 imaging system. As an independent reference, measurements of turbidity were collected concurrent with the airborne remote sensing acquisitions, using a WET Labs EcoTriplet deployed from a kayak and turbidity was then derived from the measured backscatter. The bathymetric full waveform dataset contains a discretized sample of the full backscatter of water column and benthic layer. Therefore, the full waveform records encapsulate the water column characteristics of turbidity. A nonparametric support vector regression method is utilized to estimate water turbidity from both hyperspectral imagery and voxelized full waveform LiDAR returns, both individually and as a fused dataset. Results of all the evaluations will be presented, showing an initial turbidity prediction accuracy of approximately 1.0 NTU. We will also discuss our future strategy for enhanced fusion of the full waveform LiDAR and hyperspectral imagery for improved turbidity estimation.

  8. Effects of LiDAR Derived DEM Resolution on Hydrographic Feature Extraction

    Science.gov (United States)

    Yang, P.; Ames, D. P.; Glenn, N. F.; Anderson, D.

    2010-12-01

    This paper examines the effect of LiDAR-derived digital elevation model (DEM) resolution on digitally extracted stream networks with respect to known stream channel locations. Two study sites, Reynolds Creek Experimental Watershed (RCEW) and Dry Creek Experimental Watershed (DCEW), which represent terrain characteristics for lower and intermediate elevation mountainous watersheds in the Intermountain West, were selected as study areas for this research. DEMs reflecting bare earth ground were created from the LiDAR observations at a series of raster cell sizes (from 1 m to 60 m) using spatial interpolation techniques. The effect of DEM resolution on resulting hydrographic feature (specifically stream channel) derivation was studied. Stream length, watershed area, and sinuosity were explored at each of the raster cell sizes. Also, variation from known channel location as estimated by root mean square error (RMSE) between surveyed channel location and extracted channel was computed for each of the DEMs and extracted stream networks. As expected, the results indicate that the DEM based hydrographic extraction process provides more detailed hydrographic features at a finer resolution. RMSE between the known channel location and modeled locations generally increased with larger cell size DEM with a greater effect in the larger RCEW. Sensitivity analyses on sinuosity demonstrated that the resulting shape of streams obtained from LiDAR data matched best with the reference data at an intermediate cell size instead of highest resolution, which is at a range of cell size from 5 to 10 m likely due to original point spacing, terrain characteristics, and LiDAR noise influence. More importantly, the absolute sinuosity deviation displayed a smallest value at the cell size of 10 m in both experimental watersheds, which suggests that optimal cell size for LiDAR-derived DEMs used for hydrographic feature extraction is 10 m.

  9. Object-Based Land Use Classification using Airborne LiDAR

    Science.gov (United States)

    Antonarakis, A. S.; Richards, K. S.; Brasington, J.

    2007-12-01

    Better information on roughness of various types of vegetation is needed for use in resistance equations and eventually in flood modelling. These types include woody riparian species with different structural characteristics. Remote Sensing information such as 3D point cloud data from LiDAR can be used as a tool for extracting simple roughness information relevant for the condition of below canopy flow, as well as roughness relevant for more complex tree morphology that affects the flow when it enters the canopy levels. A strategy for extracting roughness parameters from remote sensing techniques is to use a data fusion object classification model. This means that multiple datasets such as LiDAR, digital aerial photography, ground data and satellite data can be combined to produce roughness parameters estimated for different vegetative patches, which can subsequently be mapped spatially using a classification methodology. Airborne LiDAR is used in this study in order to classify forest and ground types quickly and efficiently without the need for manipulating multispectral image files. LiDAR has the advantage of being able to create elevation surfaces that are in 3D, while also having information on LiDAR intensity values, thus it is a spatial and spectral segmentation tool. This classification method also uses point distribution frequency criteria to differentiate between land cover types. The classification of three meanders of the Garonne and Allier rivers in France has demonstrated overall classification accuracies of 95%. Five types of riparian forest were classified with accuracies between 66-98%. These forest types included planted and natural forest stands of different ages. Classifications of short vegetation and bare earth also produced high accuracies averaging above 90%.

  10. Building Change Detection Using Old Aerial Images and New LiDAR Data

    Directory of Open Access Journals (Sweden)

    Shouji Du

    2016-12-01

    Full Text Available Building change detection is important for urban area monitoring, disaster assessment and updating geo-database. 3D information derived from image dense matching or airborne light detection and ranging (LiDAR is very effective for building change detection. However, combining 3D data from different sources is challenging, and so far few studies have focused on building change detection using both images and LiDAR data. This study proposes an automatic method to detect building changes in urban areas using aerial images and LiDAR data. First, dense image matching is carried out to obtain dense point clouds and then co-registered LiDAR point clouds using the iterative closest point (ICP algorithm. The registered point clouds are further resampled to a raster DSM (Digital Surface Models. In a second step, height difference and grey-scale similarity are calculated as change indicators and the graph cuts method is employed to determine changes considering the contexture information. Finally, the detected results are refined by removing the non-building changes, in which a novel method based on variance of normal direction of LiDAR points is proposed to remove vegetated areas for positive building changes (newly building or taller and nEGI (normalized Excessive Green Index is used for negative building changes (demolish building or lower. To evaluate the proposed method, a test area covering approximately 2.1 km2 and consisting of many different types of buildings is used for the experiment. Results indicate 93% completeness with correctness of 90.2% for positive changes, while 94% completeness with correctness of 94.1% for negative changes, which demonstrate the promising performance of the proposed method.

  11. A universal airborne LiDAR approach for tropical forest carbon mapping.

    Science.gov (United States)

    Asner, Gregory P; Mascaro, Joseph; Muller-Landau, Helene C; Vieilledent, Ghislain; Vaudry, Romuald; Rasamoelina, Maminiaina; Hall, Jefferson S; van Breugel, Michiel

    2012-04-01

    Airborne light detection and ranging (LiDAR) is fast turning the corner from demonstration technology to a key tool for assessing carbon stocks in tropical forests. With its ability to penetrate tropical forest canopies and detect three-dimensional forest structure, LiDAR may prove to be a major component of international strategies to measure and account for carbon emissions from and uptake by tropical forests. To date, however, basic ecological information such as height-diameter allometry and stand-level wood density have not been mechanistically incorporated into methods for mapping forest carbon at regional and global scales. A better incorporation of these structural patterns in forests may reduce the considerable time needed to calibrate airborne data with ground-based forest inventory plots, which presently necessitate exhaustive measurements of tree diameters and heights, as well as tree identifications for wood density estimation. Here, we develop a new approach that can facilitate rapid LiDAR calibration with minimal field data. Throughout four tropical regions (Panama, Peru, Madagascar, and Hawaii), we were able to predict aboveground carbon density estimated in field inventory plots using a single universal LiDAR model (r ( 2 ) = 0.80, RMSE = 27.6 Mg C ha(-1)). This model is comparable in predictive power to locally calibrated models, but relies on limited inputs of basal area and wood density information for a given region, rather than on traditional plot inventories. With this approach, we propose to radically decrease the time required to calibrate airborne LiDAR data and thus increase the output of high-resolution carbon maps, supporting tropical forest conservation and climate mitigation policy.

  12. BUILDING DAMAGE ASSESSMENT AFTER EARTHQUAKE USING POST-EVENT LiDAR DATA

    Directory of Open Access Journals (Sweden)

    H. Rastiveis

    2015-12-01

    Full Text Available After an earthquake, damage assessment plays an important role in leading rescue team to help people and decrease the number of mortality. Damage map is a map that demonstrates collapsed buildings with their degree of damage. With this map, finding destructive buildings can be quickly possible. In this paper, we propose an algorithm for automatic damage map generation after an earthquake using post-event LiDAR Data and pre-event vector map. The framework of the proposed approach has four main steps. To find the location of all buildings on LiDAR data, in the first step, LiDAR data and vector map are registered by using a few number of ground control points. Then, building layer, selected from vector map, are mapped on the LiDAR data and all pixels which belong to the buildings are extracted. After that, through a powerful classifier all the extracted pixels are classified into three classes of “debris”, “intact building” and “unclassified”. Since textural information make better difference between “debris” and “intact building” classes, different textural features are applied during the classification. After that, damage degree for each candidate building is estimated based on the relation between the numbers of pixels labelled as “debris” class to the whole building area. Calculating the damage degree for each candidate building, finally, building damage map is generated. To evaluate the ability proposed method in generating damage map, a data set from Port-au-Prince, Haiti’s capital after the 2010 Haiti earthquake was used. In this case, after calculating of all buildings in the test area using the proposed method, the results were compared to the damage degree which estimated through visual interpretation of post-event satellite image. Obtained results were proved the reliability of the proposed method in damage map generation using LiDAR data.

  13. LiDAR-IMU Time Delay Calibration Based on Iterative Closest Point and Iterated Sigma Point Kalman Filter.

    Science.gov (United States)

    Liu, Wanli

    2017-03-08

    The time delay calibration between Light Detection and Ranging (LiDAR) and Inertial Measurement Units (IMUs) is an essential prerequisite for its applications. However, the correspondences between LiDAR and IMU measurements are usually unknown, and thus cannot be computed directly for the time delay calibration. In order to solve the problem of LiDAR-IMU time delay calibration, this paper presents a fusion method based on iterative closest point (ICP) and iterated sigma point Kalman filter (ISPKF), which combines the advantages of ICP and ISPKF. The ICP algorithm can precisely determine the unknown transformation between LiDAR-IMU; and the ISPKF algorithm can optimally estimate the time delay calibration parameters. First of all, the coordinate transformation from the LiDAR frame to the IMU frame is realized. Second, the measurement model and time delay error model of LiDAR and IMU are established. Third, the methodology of the ICP and ISPKF procedure is presented for LiDAR-IMU time delay calibration. Experimental results are presented that validate the proposed method and demonstrate the time delay error can be accurately calibrated.

  14. Analysis of the Influence of Plot Size and LiDAR Density on Forest Structure Attribute Estimates

    OpenAIRE

    Luis A. Ruiz; Txomin Hermosilla; Francisco Mauro; Miguel Godino

    2014-01-01

    Licencia Creative Commons: Attribution 3.0 Unported (CC BY 3.0) This paper assesses the combined effect of field plot size and LiDAR density on the estimation of four forest structure attributes: volume, total biomass, basal area and canopy cover. A total of 21 different plot sizes were considered, obtained by decreasing the field measured plot radius value from 25 to 5 m with regular intervals of 1 m. LiDAR data densities were simulated by randomly removing LiDAR pulses until ...

  15. Capabilities of the bathymetric Hawk Eye LiDAR for coastal habitat mapping: A case study within a Basque estuary

    Science.gov (United States)

    Chust, Guillem; Grande, Maitane; Galparsoro, Ibon; Uriarte, Adolfo; Borja, Ángel

    2010-10-01

    The bathymetric LiDAR system is an airborne laser that detects sea bottom at high vertical and horizontal resolutions in shallow coastal waters. This study assesses the capabilities of the airborne bathymetric LiDAR sensor (Hawk Eye system) for coastal habitat mapping in the Oka estuary (within the Biosphere Reserve of Urdaibai, SE Bay of Biscay, northern Spain), where water conditions are moderately turbid. Three specific objectives were addressed: 1) to assess the data quality of the Hawk Eye LiDAR, both for terrestrial and subtidal zones, in terms of height measurement density, coverage, and vertical accuracy; 2) to compare bathymetric LiDAR with a ship-borne multibeam echosounder (MBES) for different bottom types and depth ranges; and 3) to test the discrimination potential of LiDAR height and reflectance information, together with multi-spectral imagery (three visible and near infrared bands), for the classification of 22 salt marsh and rocky shore habitats, covering supralittoral, intertidal and subtidal zones. The bathymetric LiDAR Hawk Eye data enabled the generation of a digital elevation model (DEM) of the Oka estuary, at 2 m of horizontal spatial resolution in the terrestrial zone (with a vertical accuracy of 0.15 m) and at 4 m within the subtidal, extending a water depth of 21 m. Data gaps occurred in 14.4% of the area surveyed with the LiDAR (13.69 km 2). Comparison of the LiDAR system and the MBES showed no significant mean difference in depth. However, the Root Mean Square error of the former was high (0.84 m), especially concentrated upon rocky (0.55-1.77 m) rather than in sediment bottoms (0.38-0.62 m). The potential of LiDAR topographic variables and reflectance alone for discriminating 15 intertidal and submerged habitats was low (with overall classification accuracy between 52.4 and 65.4%). In particular, reflectance retrieved for this case study has been found to be not particularly useful for classification purposes. The combination of the LiDAR

  16. DArT markers: diversity analyses, genomes comparison, mapping and integration with SSR markers in Triticum monococcum

    Directory of Open Access Journals (Sweden)

    Huttner Eric

    2009-09-01

    Full Text Available Abstract Background Triticum monococcum (2n = 2x = 14 is an ancient diploid wheat with many useful traits and is used as a model for wheat gene discovery. DArT (Diversity Arrays Technology employs a hybridisation-based approach to type thousands of genomic loci in parallel. DArT markers were developed for T. monococcum to assess genetic diversity, compare relationships with hexaploid genomes, and construct a genetic linkage map integrating DArT and microsatellite markers. Results A DArT array, consisting of 2304 hexaploid wheat, 1536 tetraploid wheat, 1536 T. monococcum as well as 1536 T. boeoticum representative genomic clones, was used to fingerprint 16 T. monococcum accessions of diverse geographical origins. In total, 846 polymorphic DArT markers were identified, of which 317 were of T. monococcum origin, 246 of hexaploid, 157 of tetraploid, and 126 of T. boeoticum genomes. The fingerprinting data indicated that the geographic origin of T. monococcum accessions was partially correlated with their genetic variation. DArT markers could also well distinguish the genetic differences amongst a panel of 23 hexaploid wheat and nine T. monococcum genomes. For the first time, 274 DArT markers were integrated with 82 simple sequence repeat (SSR and two morphological trait loci in a genetic map spanning 1062.72 cM in T. monococcum. Six chromosomes were represented by single linkage groups, and chromosome 4Am was formed by three linkage groups. The DArT and SSR genetic loci tended to form independent clusters along the chromosomes. Segregation distortion was observed for one third of the DArT loci. The Ba (black awn locus was refined to a 23.2 cM region between the DArT marker locus wPt-2584 and the microsatellite locus Xgwmd33 on 1Am; and the Hl (hairy leaf locus to a 4.0 cM region between DArT loci 376589 and 469591 on 5Am. Conclusion DArT is a rapid and efficient approach to develop many new molecular markers for genetic studies in T. monococcum. The

  17. El escritor no es nada, Nadie: Saer contra una estética latinoamericana

    Directory of Open Access Journals (Sweden)

    Rafael Arce

    2009-06-01

    Full Text Available En un ensayo estupendo, Alejo Carpentier señala la dificultad que entraña dar definiciones sobre nociones harto complejas que atraviesan la historia del arte y de la literatura. No obstante, su recorrido lo obliga a asumir cierta definición o, mejor, cierto rasgo conceptual que permitiría el acceso a una cierta definición, para el caso de su interés, del barroco, noción harto compleja que lo ayudará para llegar a la de lo real maravilloso. Después de una breve síntesis acerca de los avatares de esta noción a través de la historia del arte, ilustrada sobre todo por ejemplos tomados de la arquitectura, Carpentier se decide por este rasgo capital: lo que caracterizaría más propiamente al barroco como posición estética es un declarado horror al vacío. La caracterización, el rasgo conceptual, es de tipo causal: el horror al vacío sería la causa, el motivo, del movimiento, o de la actitud más bien, barroca.

  18. Point‐of‐sale promotion of breastmilk substitutes and commercially produced complementary foods in Cambodia, Nepal, Senegal and Tanzania

    Science.gov (United States)

    Pereira, Catherine; Sweet, Lara; Khin, Mengkheang; Ndiaye Coly, Aminata; Sy Gueye, Ndeye Yaga; Adhikary, Indu; Dhungel, Shrid; Makafu, Cecilia; Zehner, Elizabeth; Huffman, Sandra L.

    2016-01-01

    Abstract In order to assess the prevalence of point‐of‐sale promotions of infant and young child feeding products in Phnom Penh, Cambodia; Kathmandu Valley, Nepal; Dakar Department, Senegal; and Dar es Salaam, Tanzania, approximately 30 retail stores per site, 121 in total, were visited. Promotional activity for breastmilk substitutes (BMS) and commercially produced complementary foods in each site were recorded. Point‐of‐sale promotion of BMS occurred in approximately one‐third of sampled stores in Phnom Penh and Dakar Department but in 3.2% and 6.7% of stores in Kathmandu Valley and Dar es Salaam, respectively. Promotion of commercially produced complementary foods was highly prevalent in Dakar Department with half of stores having at least one promotion, while promotions for these products occurred in 10% or less of stores in the other three sites. While promotion of BMS in stores is legal in Senegal, it is prohibited in Cambodia without prior permission of the Ministry of Health/Ministry of Information and prohibited in both Nepal and Tanzania. Strengthening legislation in Senegal and enforcing regulations in Cambodia could help to prevent such promotion that can negatively affect breastfeeding practices. Key messages Even in countries such as Cambodia, Nepal and Tanzania where point‐of‐sale promotion is restricted, promotions of BMS were observed (in nearly one‐third of stores in Phnom Penh and less than 10% in Dar es Salaam and Kathmandu).Limited promotion of commercially produced complementary foods was evident (less than 10% of stores had a promotion for such foods), except in Dakar Department, where promotions were found in half of stores.Efforts are needed to strengthen monitoring, regulation and enforcement of restrictions on the promotion of BMS.Manufacturers and distributors should take responsibility for compliance with national regulations and global policies pertaining to the promotion of breastmilk substitutes. PMID:27061961

  19. Evaluation of hyperspectral LiDAR for monitoring rice leaf nitrogen by comparison with multispectral LiDAR and passive spectrometer

    Science.gov (United States)

    Sun, Jia; Shi, Shuo; Gong, Wei; Yang, Jian; Du, Lin; Song, Shalei; Chen, Biwu; Zhang, Zhenbing

    2017-01-01

    Fast and nondestructive assessment of leaf nitrogen concentration (LNC) is critical for crop growth diagnosis and nitrogen management guidance. In the last decade, multispectral LiDAR (MSL) systems have promoted developments in the earth and ecological sciences with the additional spectral information. With more wavelengths than MSL, the hyperspectral LiDAR (HSL) system provides greater possibilities for remote sensing crop physiological conditions. This study compared the performance of ASD FieldSpec Pro FR, MSL, and HSL for estimating rice (Oryza sativa) LNC. Spectral reflectance and biochemical composition were determined in rice leaves of different cultivars (Yongyou 4949 and Yangliangyou 6) throughout two growing seasons (2014–2015). Results demonstrated that HSL provided the best indicator for predicting rice LNC, yielding a coefficient of determination (R2) of 0.74 and a root mean square error of 2.80 mg/g with a support vector machine, similar to the performance of ASD (R2 = 0.73). Estimation of rice LNC could be significantly improved with the finer spectral resolution of HSL compared with MSL (R2 = 0.56).

  20. Evaluation of hyperspectral LiDAR for monitoring rice leaf nitrogen by comparison with multispectral LiDAR and passive spectrometer

    Science.gov (United States)

    Sun, Jia; Shi, Shuo; Gong, Wei; Yang, Jian; Du, Lin; Song, Shalei; Chen, Biwu; Zhang, Zhenbing

    2017-01-01

    Fast and nondestructive assessment of leaf nitrogen concentration (LNC) is critical for crop growth diagnosis and nitrogen management guidance. In the last decade, multispectral LiDAR (MSL) systems have promoted developments in the earth and ecological sciences with the additional spectral information. With more wavelengths than MSL, the hyperspectral LiDAR (HSL) system provides greater possibilities for remote sensing crop physiological conditions. This study compared the performance of ASD FieldSpec Pro FR, MSL, and HSL for estimating rice (Oryza sativa) LNC. Spectral reflectance and biochemical composition were determined in rice leaves of different cultivars (Yongyou 4949 and Yangliangyou 6) throughout two growing seasons (2014–2015). Results demonstrated that HSL provided the best indicator for predicting rice LNC, yielding a coefficient of determination (R2) of 0.74 and a root mean square error of 2.80 mg/g with a support vector machine, similar to the performance of ASD (R2 = 0.73). Estimation of rice LNC could be significantly improved with the finer spectral resolution of HSL compared with MSL (R2 = 0.56). PMID:28091610

  1. Protection des données

    OpenAIRE

    2009-01-01

    L’accélération de la diffusion d’Internet et de ses applications oblige les législateurs à re­voir sans cesse la réglementation de la protection des données, qu’il s’agisse des don­nées privées, du secret médical ou encore de la lutte contre le piratage économique. Voici un précis actualisé de l’état du droit allemand en la matière (GOLA/KLUG). Ces évolutions créent toutefois un conflit d’intérêt en matière de droit de l’information, que re­trace, exemples à l’appui, le rapport annuel 2004 qu...

  2. IsoDAR@KamLAND: A Conceptual Design Report for the Technical Facility

    CERN Document Server

    Abs, M; Alonso, J R; Axani, S; Barletta, W A; Barlow, R; Bartoszek, L; Bungau, A; Calabretta, L; Calanna, A; Campo, D; Castro, G; Celona, L; Collin, G H; Conrad, J M; Gammino, S; Johnson, R; Karagiorgi, G; Kayser, S; Kleeven, W; Kolano, A; Labrecque, F; Loinaz, W A; Minervini, J; Moulai, M H; Okuno, H; Owen, H; Papavassiliou, V; Shaevitz, M H; Shimizu, I; Shokair, T M; Sorensen, K F; Spitz, J; Toups, M; Vagins, M; Van Bibber, K; Wascko, M O; Winklehner, D; Winslow, L A; Yang, J J

    2015-01-01

    This conceptual design report describes the technical facility for the IsoDAR electron-antineutrino source at KamLAND. The IsoDAR source will allow an impressive program of neutrino oscillation and electroweak physics to be performed at KamLAND. This report provides information on the physics case, the conceptual design for the subsystems, alternative designs considered, specifics of installation at KamLAND, and identified needs for future development. We discuss the risks we have identified and our approach to mitigating those risks with this design. A substantial portion of the conceptual design is based on three years of experimental efforts and on industry experience. This report also includes information on the conventional facilities.

  3. Contour Cluster Shape Analysis for Building Damage Detection from Post-earthquake Airborne LiDAR

    Directory of Open Access Journals (Sweden)

    HE Meizhang

    2015-04-01

    Full Text Available Detection of the damaged building is the obligatory step prior to evaluate earthquake casualty and economic losses. It's very difficult to detect damaged buildings accurately based on the assumption that intact roofs appear in laser data as large planar segments whereas collapsed roofs are characterized by many small segments. This paper presents a contour cluster shape similarity analysis algorithm for reliable building damage detection from the post-earthquake airborne LiDAR point cloud. First we evaluate the entropies of shape similarities between all the combinations of two contour lines within a building cluster, which quantitatively describe the shape diversity. Then the maximum entropy model is employed to divide all the clusters into intact and damaged classes. The tests on the LiDAR data at El Mayor-Cucapah earthquake rupture prove the accuracy and reliability of the proposed method.

  4. Ugdymo vientisumas M. Montessori darželyje ir šeimoje

    OpenAIRE

    Červiakova, Vida

    2011-01-01

    Šiame darbe buvo siekiama ištirti ugdymo vientisumo M. Montessori darželyje ir šeimoje ypatumus teoriniu bei praktiniu aspektais. Siekiant šio tikslo pirmiausia atskleista M. Montessori pedagoginės sistemos samprata, apibrėžiamos ugdymo metodų vientisumo apraiškos šeimoje ir darželyje, išskiriamos ugdymo vientisumo įgyvendinimo problemos. Analizuojant, kaip pedagogai ir tėvai suvokia M. Montessori sistemą, koks pedagogų ir tėvų požiūris į vaiką, taip pat lyginant vaiko aplinką, vaiko veiklos ...

  5. Droit des données personnelles

    OpenAIRE

    Vétois, Jacques

    2016-01-01

    Comme le droit de l’informatique, celui des données personnelles reste flou dans l’esprit de nos concitoyens. Et pourtant, il nous concerne tous directement. La loi Hadopi vient, par exemple, d’instituer la « riposte graduée » pour lutter contre le piratage des films ou de la musique. En neuf mois, 18 millions d’infractions ont été constatées et quelques internautes au bout du compte seront passibles d’une amende. Si vous utilisez les réseaux sociaux, peut-être vous interrogez-vous sur ce qui...

  6. ULCERA GASTRODUODENAL EM CÃES

    Directory of Open Access Journals (Sweden)

    Francisco Assis Uma Costa

    1993-12-01

    Full Text Available As ulcerações no sistema digestivo de cães são consideradas raras. São descritos dois casos de úlcera gastroduodenal em cães. O primeiro animal apresentou úlcera no duodeno próxima!. O segundo mostrou úlcera perfurada na região pilórica do estômago. Nenhum dos animais apresentou evidências de sangramento, mas as lesões eram profundas e arredondadas. Não houve evidência de patologias concorrentes.

  7. Artes de viver em mulheres de camadas populares: o cotidiano de mães da comunidade São Remo

    OpenAIRE

    Mariana Peres Stucchi

    2009-01-01

    Este trabalho nasceu do contato com mães de comunidade pobre, que precisam dar conta de jornadas triplas de trabalho: casa, filhos, trabalho; quando não quíntuplas pensando que precisam cuidar de ser esposa e mulher também. A questão é como essas mulheres conseguem renovar suas energias para a luta diária pela vida? Será que há condições de só viver de trabalho, de exigências externas, de responsabilidades? Assim encaminhouse a discussão sobre o lazer e o trabalho, pensandoos como instâncias ...

  8. EL INFORME DE AUDITORÍA DE CUENTAS ANUALES ADAPTADO A LAS NORMAS INTERNACIONALES DE AUDITORÍA EN ESPAÑA (NIA-ES)

    OpenAIRE

    CONTELL FONTESTAD, ALBA

    2015-01-01

    [ES] El objeto del trabajo final de carrera se centra principalmente en el análisis del impacto de las nuevas Normas Internacionales de Auditoría en el informe que debe realizar el auditor a la finalización de su trabajo. Para ello se lleva a cabo un estudio de cada uno de los párrafos que comprenden el informe y las situaciones que se pueden dar para que el auditor emite un tipo u otro de opinión, siendo estas: opinión favorable, opinión con salvedades, opinión desfavorable y opinión denegad...

  9. Step by step error assessment in braided river sediment budget using airborne LiDAR data

    Science.gov (United States)

    Lallias-Tacon, S.; Liébault, F.; Piégay, H.

    2014-06-01

    Sequential airborne LiDAR surveys were used to reconstruct the sediment budget of a 7-km-long braided river channel in southeastern France following a 14-year return period flood and to improve its accuracy step by step. Data processing involved (i) surface matching of the sequential point clouds, (ii) spatially distributed propagation of uncertainty based on surface conditions of the channel, and (iii) water depth subtraction from the digital elevation models based on water depths measured in the field. The respective influence of each processing step on sediment budget computation was systematically documented. This showed that surface matching and water depth subtraction both have a considerable effect on the net sediment budget. Although DEM of difference thresholding based on uncertainty analysis on absolute elevation values had a smaller effect on the sediment budget, this step is crucial for the production of a comprehensive map of channel deformations. A large independent data set of RTK-GPS checkpoints was used to control the quality of the LiDAR altimetry. The results showed that high density (7-9 points/m2) airborne LiDAR surveys can provide a very high level of detection of elevation changes on the exposed surfaces of the channel, with a 95% confidence interval level of detection between 19 and 30 cm. Change detection from LiDAR data revealed that 54% of the pre-flood active channel was reworked by the flood. The braided channel pattern was highly disturbed by the flood owing to the occurrence of several channel avulsions.

  10. Strategies for minimizing sample size for use in airborne LiDAR-based forest inventory

    Science.gov (United States)

    Junttila, Virpi; Finley, Andrew O.; Bradford, John B.; Kauranne, Tuomo

    2013-01-01

    Recently airborne Light Detection And Ranging (LiDAR) has emerged as a highly accurate remote sensing modality to be used in operational scale forest inventories. Inventories conducted with the help of LiDAR are most often model-based, i.e. they use variables derived from LiDAR point clouds as the predictive variables that are to be calibrated using field plots. The measurement of the necessary field plots is a time-consuming and statistically sensitive process. Because of this, current practice often presumes hundreds of plots to be collected. But since these plots are only used to calibrate regression models, it should be possible to minimize the number of plots needed by carefully selecting the plots to be measured. In the current study, we compare several systematic and random methods for calibration plot selection, with the specific aim that they be used in LiDAR based regression models for forest parameters, especially above-ground biomass. The primary criteria compared are based on both spatial representativity as well as on their coverage of the variability of the forest features measured. In the former case, it is important also to take into account spatial auto-correlation between the plots. The results indicate that choosing the plots in a way that ensures ample coverage of both spatial and feature space variability improves the performance of the corresponding models, and that adequate coverage of the variability in the feature space is the most important condition that should be met by the set of plots collected.

  11. Identification of four Drosophila allatostatins as the cognate ligands for the Drosophila orphan receptor DAR-2

    DEFF Research Database (Denmark)

    Lenz, C; Williamson, M; Hansen, G N

    2001-01-01

    -Thr-Arg-Pro-Gln-Pro-Phe-Asn-Phe-Gly-Leu-NH(2)) is the most effective in causing a second messenger cascade (measured as bioluminescence; threshold, 10(-9) M; EC(50), 10(-8) M), whereas the others are less effective and about equally potent (EC(50), 8 x 10(-8) M). Northern blots showed that the DAR-2 gene is expressed in embryos, larvae...

  12. Abu Dhabi Basemap Update Using the LiDAR Mobile Mapping Technology

    Science.gov (United States)

    Alshaiba, Omar; Amparo Núñez-Andrés, M.; Lantada, Nieves

    2016-04-01

    Mobile LiDAR system provides a new technology which can be used to update geospatial information by direct and rapid data collection. This technology is faster than the traditional survey ways and has lower cost. Abu Dhabi Municipal System aims to update its geospatial system frequently as the government entities have invested heavily in GIS technology and geospatial data to meet the repaid growth in the infrastructure and construction projects in recent years. The Emirate of Abu Dhabi has witnessed a huge growth in infrastructure and construction projects in recent years. Therefore, it is necessary to develop and update its basemap system frequently to meet their own organizational needs. Currently, the traditional ways are used to update basemap system such as human surveyors, GPS receivers and controller (GPS assigned computer). Then the surveyed data are downloaded, edited and reviewed manually before it is merged to the basemap system. Traditional surveying ways may not be applicable in some conditions such as; bad weather, difficult topographic area and boundary area. This paper presents a proposed methodology which uses the Mobile LiDAR system to update basemap in Abu Dhabi by using daily transactions services. It aims to use and integrate the mobile LiDAR technology into the municipality's daily workflow such that it becomes the new standard cost efficiency operating procedure for updating the base-map in Abu Dhabi Municipal System. On another note, the paper will demonstrate the results of the innovated workflow for the base-map update using the mobile LiDAR point cloud and few processing algorithms.

  13. Flying Under the LiDAR: Relating Forest Structure to Bat Community Diversity

    Science.gov (United States)

    Swanson, A. C.; Weishampel, J. F.

    2015-12-01

    Bats are important to many ecological processes such as pollination, insect (and by proxy, disease) control, and seed dispersal and can be used to monitor ecosystem health. However, they are facing unprecedented extinction risks from habitat degradation as well as pressures from pathogens (e.g., white-nose syndrome) and wind turbines. LiDAR allows ecologists to measure structural variables of forested landscapes with increased precision and accuracy at broader spatial scales than previously possible. This study used airborne LiDAR to classify forest habitat/canopy structure at the Ordway-Swisher Biological Station (OSBS) in north central Florida. LiDAR data were acquired by the NEON airborne observation platform in summer 2014. OSBS consists of open-canopy pine savannas, closed-canopy hardwood hammocks, and seasonally wet prairies. Multiple forest structural parameters (e.g., mean, maximum, and standard deviation of height returns) were derived from LiDAR point clouds using the USDA software program FUSION. K-means clustering was used to segregate each 5x5 m raster across the ~3765 ha OSBS area into six different clusters based on the derived canopy metrics. Cluster averages for maximum, mean, and standard deviation of return heights ranged from 0 to 19.4 m, 0 to 15.3 m, and 0 to 3.0 m, respectively. To determine the relationships among these landscape-canopy features and bat species diversity and abundances, AnaBat II bat detectors were deployed from May to September in 2015 stratified by these distinct clusters. Bat calls were recorded from sunset to sunrise during each sampling period. Species were identified using AnalookW. A statistical regression model selection approach was performed in order to evaluate how forest attributes such as understory clutter, open regions, open and closed canopy, etc. influence bat communities. This knowledge provides a deeper understanding of habitat-species interactions to better manage survival of these species.

  14. Quantitative study of tectonic geomorphology along Haiyuan fault based on airborne LiDAR

    Science.gov (United States)

    Chen, Tao; Zhang, Pei Zhen; Liu, Jing; Li, Chuan You; Ren, Zhi Kun; Hudnut, Kenneth W.

    2014-01-01

    High-precision and high-resolution topography are the fundamental data for active fault research. Light detection and ranging (LiDAR) presents a new approach to build detailed digital elevation models effectively. We take the Haiyuan fault in Gansu Province as an example of how LiDAR data may be used to improve the study of active faults and the risk assessment of related hazards. In the eastern segment of the Haiyuan fault, the Shaomayin site has been comprehensively investigated in previous research because of its exemplary tectonic topographic features. Based on unprecedented LiDAR data, the horizontal and vertical coseismic offsets at the Shaomayin site are described. The measured horizontal value is about 8.6 m, and the vertical value is about 0.8 m. Using prior dating ages sampled from the same location, we estimate the horizontal slip rate as 4.0 ± 1.0 mm/a with high confidence and define that the lower bound of the vertical slip rate is 0.4 ± 0.1 mm/a since the Holocene. LiDAR data can repeat the measurements of field work on quantifying offsets of tectonic landform features quite well. The offset landforms are visualized on an office computer workstation easily, and specialized software may be used to obtain displacement quantitatively. By combining precious chronological results, the fundamental link between fault activity and large earthquakes is better recognized, as well as the potential risk for future earthquake hazards.

  15. Rafael Núñez visto por Rubén Darío

    Directory of Open Access Journals (Sweden)

    Alberto Miramón

    1966-12-01

    Full Text Available Entre los grandes timbres que nadie escatima al contradictorio filósofo del Cabrero, está el haber comprendido y ayudado a los maestros del modernismo de América en sus comienzos - José Asunción Silva y Rubén Darío-. Ambos lo conocieron y trataron en su retiro de Cartagena de Indias; ambos escribieron sus impresiones sobre este trato directo y personal.

  16. Estimating Volume, Biomass, and Carbon in Hedmark County, Norway Using a Profiling LiDAR

    Science.gov (United States)

    Nelson, Ross; Naesset, Erik; Gobakken, T.; Gregoire, T.; Stahl, G.

    2009-01-01

    A profiling airborne LiDAR is used to estimate the forest resources of Hedmark County, Norway, a 27390 square kilometer area in southeastern Norway on the Swedish border. One hundred five profiling flight lines totaling 9166 km were flown over the entire county; east-west. The lines, spaced 3 km apart north-south, duplicate the systematic pattern of the Norwegian Forest Inventory (NFI) ground plot arrangement, enabling the profiler to transit 1290 circular, 250 square meter fixed-area NFI ground plots while collecting the systematic LiDAR sample. Seven hundred sixty-three plots of the 1290 plots were overflown within 17.8 m of plot center. Laser measurements of canopy height and crown density are extracted along fixed-length, 17.8 m segments closest to the center of the ground plot and related to basal area, timber volume and above- and belowground dry biomass. Linear, nonstratified equations that estimate ground-measured total aboveground dry biomass report an R(sup 2) = 0.63, with an regression RMSE = 35.2 t/ha. Nonstratified model results for the other biomass components, volume, and basal area are similar, with R(sup 2) values for all models ranging from 0.58 (belowground biomass, RMSE = 8.6 t/ha) to 0.63. Consistently, the most useful single profiling LiDAR variable is quadratic mean canopy height, h (sup bar)(sub qa). Two-variable models typically include h (sup bar)(sub qa) or mean canopy height, h(sup bar)(sub a), with a canopy density or a canopy height standard deviation measure. Stratification by productivity class did not improve the nonstratified models, nor did stratification by pine/spruce/hardwood. County-wide profiling LiDAR estimates are reported, by land cover type, and compared to NFI estimates.

  17. SUBTROPICAL FOREST BIOMASS ESTIMATION USING AIRBORNE LiDAR AND HYPERSPECTRAL DATA

    OpenAIRE

    Pang, Yong; Li, Zengyuan

    2016-01-01

    Forests have complex vertical structure and spatial mosaic pattern. Subtropical forest ecosystem consists of vast vegetation species and these species are always in a dynamic succession stages. It is very challenging to characterize the complexity of subtropical forest ecosystem. In this paper, CAF’s (The Chinese Academy of Forestry) LiCHy (LiDAR, CCD and Hyperspectral) Airborne Observation System was used to collect waveform Lidar and hyperspectral data in Puer forest region, Yunnan province...

  18. Estimating Tree Frontal Area in Urban Areas Using Terrestrial LiDAR Data

    Directory of Open Access Journals (Sweden)

    Yitong Jiang

    2016-05-01

    Full Text Available Surface roughness parameters, such as roughness length and displacement height, impact the estimation of surface moisture, and the frontal areas of buildings and trees are two components that contribute to surface roughness in urban areas. Research on tree frontal area has not been conducted in urban areas before, and we hope to fill that gap in the literature with this study by using Terrestrial Light Detection and Ranging (LiDAR data to estimate tree frontal areas in Warren Township, Indianapolis, IN, USA. We first estimated the frontal areas of individual trees based on their morphology, then calibrated a regression model to estimate the tree frontal area in 30 m pixels using parameters derived from LiDAR data and tree inventory data. The parameters included tree crown base area, height, width, conditions, defects, maintenances, genera, and land use. The validation shows that R2 yielded values ranging from 0.84 to 0.88, and RMSEs varied with tree category. The tree categories were identified based on the height and broadness of the canopy, which indicated the degree of resistance to air flow. This type of model can be used to empirically determine local roughness values at the tree-level for any city with a complete tree inventory. With the strong correlation between trees’ frontal area and crown base area, this model may also be used to determine local roughness value at 30 m resolution with NLCD (National Land Cover Database tree canopy cover data as a component. A proper tree categorization according to the vertical air resistance, e.g., height and canopy density, was effective to reduce the RMSE in tree frontal area estimation. Geometric parameters, such as height, crown base height, and crown base area extracted from Airborne LiDAR, which demand less storage and computation capacity, may also be sufficient for tree frontal area estimation in the areas where Terrestrial LiDAR is not available.

  19. Road centerline extraction from airborne LiDAR point cloud based on hierarchical fusion and optimization

    Science.gov (United States)

    Hui, Zhenyang; Hu, Youjian; Jin, Shuanggen; Yevenyo, Yao Ziggah

    2016-08-01

    Road information acquisition is an important part of city informatization construction. Airborne LiDAR provides a new means of acquiring road information. However, the existing road extraction methods using LiDAR point clouds always decide the road intensity threshold based on experience, which cannot obtain the optimal threshold to extract a road point cloud. Moreover, these existing methods are deficient in removing the interference of narrow roads and several attached areas (e.g., parking lot and bare ground) to main roads extraction, thereby imparting low completeness and correctness to the city road network extraction result. Aiming at resolving the key technical issues of road extraction from airborne LiDAR point clouds, this paper proposes a novel method to extract road centerlines from airborne LiDAR point clouds. The proposed approach is mainly composed of three key algorithms, namely, Skewness balancing, Rotating neighborhood, and Hierarchical fusion and optimization (SRH). The skewness balancing algorithm used for the filtering was adopted as a new method for obtaining an optimal intensity threshold such that the "pure" road point cloud can be obtained. The rotating neighborhood algorithm on the other hand was developed to remove narrow roads (corridors leading to parking lots or sidewalks), which are not the main roads to be extracted. The proposed hierarchical fusion and optimization algorithm caused the road centerlines to be unaffected by certain attached areas and ensured the road integrity as much as possible. The proposed method was tested using the Vaihingen dataset. The results demonstrated that the proposed method can effectively extract road centerlines in a complex urban environment with 91.4% correctness and 80.4% completeness.

  20. LIDAR Products, LiDAR, Published in 2006, 1:1200 (1in=100ft) scale, Dodge County, Wisconsin.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This LIDAR Products dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from LIDAR information as of 2006. It is described as 'LiDAR'. Data...

  1. 2005 US Army Corps of Engineers (USACE) Post-Hurricane Katrina LiDAR: Mississippi and Western Alabama

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — LiDAR data was acquired for the U.S. Army Corps of Engineers (USACE), Mobile District in September-October 2005 along the coastline of Hancock, Harrison, Jackson...

  2. 2007 Oregon Department of Geology and Mineral Industries (DoGAMI) LiDAR: Northwest Oregon and Portland Metro Area

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. collected Light Detection and Ranging (LiDAR) data for the Oregon Department of Geology and Mineral Industries (DoGAMI) and the Oregon...

  3. 2006 US Army Corps of Engineers(USACE) National Coastal Mapping Program, Great Lakes Topo/Bathy LiDAR

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The U.S. Army Corps of Engineers collects and maintains LiDAR data including orthophotos in coastal areas of the United States and its territories. The Corps...

  4. Algorithm for Extracting Digital Terrain Models under Forest Canopy from Airborne LiDAR Data

    Directory of Open Access Journals (Sweden)

    Almasi S. Maguya

    2014-07-01

    Full Text Available Extracting digital elevationmodels (DTMs from LiDAR data under forest canopy is a challenging task. This is because the forest canopy tends to block a portion of the LiDAR pulses from reaching the ground, hence introducing gaps in the data. This paper presents an algorithm for DTM extraction from LiDAR data under forest canopy. The algorithm copes with the challenge of low data density by generating a series of coarse DTMs by using the few ground points available and using trend surfaces to interpolate missing elevation values in the vicinity of the available points. This process generates a cloud of ground points from which the final DTM is generated. The algorithm has been compared to two other algorithms proposed in the literature in three different test sites with varying degrees of difficulty. Results show that the algorithm presented in this paper is more tolerant to low data density compared to the other two algorithms. The results further show that with decreasing point density, the differences between the three algorithms dramatically increased from about 0.5m to over 10m.

  5. Range determination for generating point clouds from airborne small footprint LiDAR waveforms.

    Science.gov (United States)

    Qin, Yuchu; Vu, Tuong Thuy; Ban, Yifang; Niu, Zheng

    2012-11-05

    This paper presents a range determination approach for generating point clouds from small footprint LiDAR waveforms. Waveform deformation over complex terrain area is simulated using convolution. Drift of the peak center position is analyzed to identify the first echo returned by the illuminated objects in the LiDAR footprint. An approximate start point of peak in the waveform is estimated and adopted as the indicator of range calculation; range correction method is proposed to correct pulse widening over complex terrain surface. The experiment was carried out on small footprint LiDAR waveform data acquired by RIEGL LMS-Q560. The results suggest that the proposed approach generates more points than standard commercial products; based on field measurements, a comparative analysis between the point clouds generated by the proposed approach and the commercial software GeocodeWF indicates that: 1). the proposed approach obtained more accurate tree heights; 2). smooth surface can be achieved with low standard deviation. In summary, the proposed approach provides a satisfactory solution for range determination in estimating 3D coordinate values of point clouds, especially for correcting range information of waveforms containing deformed peaks.

  6. Drainage Structure Datasets and Effects on LiDAR-Derived Surface Flow Modeling

    Directory of Open Access Journals (Sweden)

    Ruopu Li

    2013-12-01

    Full Text Available With extraordinary resolution and accuracy, Light Detection and Ranging (LiDAR-derived digital elevation models (DEMs have been increasingly used for watershed analyses and modeling by hydrologists, planners and engineers. Such high-accuracy DEMs have demonstrated their effectiveness in delineating watershed and drainage patterns at fine scales in low-relief terrains. However, these high-resolution datasets are usually only available as topographic DEMs rather than hydrologic DEMs, presenting greater land roughness that can affect natural flow accumulation. Specifically, locations of drainage structures such as road culverts and bridges were simulated as barriers to the passage of drainage. This paper proposed a geospatial method for producing LiDAR-derived hydrologic DEMs, which incorporates data collection of drainage structures (i.e., culverts and bridges, data preprocessing and burning of the drainage structures into DEMs. A case study of GIS-based watershed modeling in South Central Nebraska showed improved simulated surface water derivatives after the drainage structures were burned into the LiDAR-derived topographic DEMs. The paper culminates in a proposal and discussion of establishing a national or statewide drainage structure dataset.

  7. Downstream hydraulic geometry relationships: Gathering reference reach-scale width values from LiDAR

    Science.gov (United States)

    Sofia, G.; Tarolli, P.; Cazorzi, F.; Dalla Fontana, G.

    2015-12-01

    This paper examines the ability of LiDAR topography to provide reach-scale width values for the analysis of downstream hydraulic geometry relationships along some streams in the Dolomites (northern Italy). Multiple reach-scale dimensions can provide representative geometries and statistics characterising the longitudinal variability in the channel, improving the understanding of geomorphic processes across networks. Starting from the minimum curvature derived from a LiDAR DTM, the proposed algorithm uses a statistical approach for the identification of the scale of analysis, and for the automatic characterisation of reach-scale bankfull widths. The downstream adjustment in channel morphology is then related to flow parameters (drainage area and stream power). With the correct planning of a LiDAR survey, uncertainties in the procedure are principally due to the resolution of the DTM. The outputs are in general comparable in quality to field survey measurements, and the procedure allows the quick comparison among different watersheds. The proposed automatic approach could improve knowledge about river systems with highly variable widths, and about systems in areas covered by vegetation or inaccessible to field surveys. With proven effectiveness, this research could offer an interesting starting point for the analysis of differences between watersheds, and to improve knowledge about downstream channel adjustment in relation, for example, to scale and landscape forcing (e.g. sediment transport, tectonics, lithology, climate, geomorphology, and anthropic pressure).

  8. Automated object detection and tracking with a flash LiDAR system

    Science.gov (United States)

    Hammer, Marcus; Hebel, Marcus; Arens, Michael

    2016-10-01

    The detection of objects, or persons, is a common task in the fields of environment surveillance, object observation or danger defense. There are several approaches for automated detection with conventional imaging sensors as well as with LiDAR sensors, but for the latter the real-time detection is hampered by the scanning character and therefore by the data distortion of most LiDAR systems. The paper presents a solution for real-time data acquisition of a flash LiDAR sensor with synchronous raw data analysis, point cloud calculation, object detection, calculation of the next best view and steering of the pan-tilt head of the sensor. As a result the attention is always focused on the object, independent of the behavior of the object. Even for highly volatile and rapid changes in the direction of motion the object is kept in the field of view. The experimental setup used in this paper is realized with an elementary person detection algorithm in medium distances (20 m to 60 m) to show the efficiency of the system for objects with a high angular speed. It is easy to replace the detection part by any other object detection algorithm and thus it is easy to track nearly any object, for example a car or a boat or an UAV in various distances.

  9. Extracting cross sections and water levels of vegetated ditches from LiDAR point clouds

    Science.gov (United States)

    Roelens, Jennifer; Dondeyne, Stefaan; Van Orshoven, Jos; Diels, Jan

    2016-12-01

    The hydrologic response of a catchment is sensitive to the morphology of the drainage network. Dimensions of bigger channels are usually well known, however, geometrical data for man-made ditches is often missing as there are many and small. Aerial LiDAR data offers the possibility to extract these small geometrical features. Analysing the three-dimensional point clouds directly will maintain the highest degree of information. A longitudinal and cross-sectional buffer were used to extract the cross-sectional profile points from the LiDAR point cloud. The profile was represented by spline functions fitted through the minimum envelop of the extracted points. The cross-sectional ditch profiles were classified for the presence of water and vegetation based on the normalized difference water index and the spatial characteristics of the points along the profile. The normalized difference water index was created using the RGB and intensity data coupled to the LiDAR points. The mean vertical deviation of 0.14 m found between the extracted and reference cross sections could mainly be attributed to the occurrence of water and partly to vegetation on the banks. In contrast to the cross-sectional area, the extracted width was not influenced by the environment (coefficient of determination R2 = 0.87). Water and vegetation influenced the extracted ditch characteristics, but the proposed method is still robust and therefore facilitates input data acquisition and improves accuracy of spatially explicit hydrological models.

  10. A signal denoising method for full-waveform LiDAR data

    Science.gov (United States)

    Azadbakht, M.; Fraser, C. S.; Zhang, C.; Leach, J.

    2013-10-01

    The lack of noise reduction methods resistant to waveform distortion can hamper correct and accurate decomposition in the processing of full-waveform LiDAR data. This paper evaluates a time-domain method for smoothing and reducing the noise level in such data. The Savitzky-Golay (S-G) approach approximates and smooths data by taking advantage of fitting a polynomial of degree d, using local least-squares. As a consequence of the integration of this method with the Singular Value Decomposition (SVD) approach, and applying this filter on the singular vectors of the SVD, satisfactory denoising results can be obtained. The results of this SVD-based S-G approach have been evaluated using two different LiDAR datasets and also compared with those of other popular methods in terms of the degree of preservation of the moments of the signal and closeness to the noisy signal. The results indicate that the SVD-based S-G approach has superior performance in denoising full-waveform LiDAR data.

  11. An Efficient Method for Automatic Road Extraction Based on Multiple Features from LiDAR Data

    Science.gov (United States)

    Li, Y.; Hu, X.; Guan, H.; Liu, P.

    2016-06-01

    The road extraction in urban areas is difficult task due to the complicated patterns and many contextual objects. LiDAR data directly provides three dimensional (3D) points with less occlusions and smaller shadows. The elevation information and surface roughness are distinguishing features to separate roads. However, LiDAR data has some disadvantages are not beneficial to object extraction, such as the irregular distribution of point clouds and lack of clear edges of roads. For these problems, this paper proposes an automatic road centerlines extraction method which has three major steps: (1) road center point detection based on multiple feature spatial clustering for separating road points from ground points, (2) local principal component analysis with least squares fitting for extracting the primitives of road centerlines, and (3) hierarchical grouping for connecting primitives into complete roads network. Compared with MTH (consist of Mean shift algorithm, Tensor voting, and Hough transform) proposed in our previous article, this method greatly reduced the computational cost. To evaluate the proposed method, the Vaihingen data set, a benchmark testing data provided by ISPRS for "Urban Classification and 3D Building Reconstruction" project, was selected. The experimental results show that our method achieve the same performance by less time in road extraction using LiDAR data.

  12. Phylogenetic Relationships between Four Salix L. Species Based on DArT Markers

    Directory of Open Access Journals (Sweden)

    Jerzy A. Przyborowski

    2013-12-01

    Full Text Available The objectives of this study were to evaluate the usefulness of DArT markers in genotypic identification of willow species and describe genetic relationships between four willow species: Salix viminalis, S. purpurea, S. alba and S. triandra. The experimental plant material comprised 53 willow genotypes of these four species, which are popularly grown in Poland. DArT markers seem to identify Salix species with a high degree of accuracy. As a result, the examined species were divided into four distinct groups which corresponded to the four analyzed species. In our study, we observed that S. triandra was very different genetically from the other species, including S. alba which is generally classified into the same subgenus of Salix. The above corroborates the findings of other authors who relied on molecular methods to reveal that the classification of S. triandra to the subgenus Salix was erroneous. The Principal Coordinate Analysis (PCoA and the neighbor-joining dendrogram also confirmed the clear division of the studied willow genotypes into four clusters corresponding to individual species. This confirmed the usefulness of DArT markers in taxonomic analyses and identification of willow species.

  13. High-Density LiDAR Mapping of the Ancient City of Mayapán

    Directory of Open Access Journals (Sweden)

    Timothy Hare

    2014-09-01

    Full Text Available A 2013 survey of a 40 square kilometer area surrounding Mayapán, Yucatan, Mexico used high-density LiDAR data to map prehispanic architecture and related natural features. Most of the area is covered by low canopy dense forest vegetation over karstic hilly terrain that impedes full coverage archaeological survey. We used LiDAR at 40 laser points per square meter to generate a bare earth digital elevation model (DEM. Results were evaluated with comparisons to previously mapped areas and with traditional archaeological survey methods for 38 settlement clusters outside of the city wall. Ground checking employed full coverage survey of selected 500 m grid squares, as well as documentation of the chronology and detail of new public and domestic settlement features and cenotes. Results identify the full extent of continued, contemporary Postclassic settlement (A.D. 1150–1450 outside of the city wall to at least 500 meters to the east, north, and west. New data also reveal an extensive modified landscape of terraformed residential hills, rejolladas, and dense settlement dating from Preclassic through Classic Periods. The LiDAR data also allow for the identification of rooms, benches, and stone property walls and lanes within the city.

  14. Petrography and geochemistry of Paleocene-Eocene limestones in the Ching-dar syncline, eastern Iran

    Institute of Scientific and Technical Information of China (English)

    S. Halimeh Hashemi Azizi; Gholamreza Mirab Shabestari; Ahmadreza Khazaei

    2014-01-01

    The Ching-dar syncline is located to the west of the city of Birjand, in the east of Iran. The ca. 500 m thick studied section at the eastern flank of the syncline contains a sequence of almost continuous shallow-marine limestones that exhibit no major sedimentary breaks or evidence for volcanic activity. Skeletal grains consist of large benthic foraminifera and green algae whereas non-skeletal grains are mostly peloids and intraclasts. They were deposited on a shallow-marine carbonate ramp. The limestones have undergone extensive diagenetic processes with varying intensities, the most important of which are micritization, cementation, compaction (chemical and mechanical), internal filling and stylolitization. Chemical analysis of the limestone samples revealed high calcium and low magnesium content. Major and minor element values were used to determine the original carbonate mineralogy of these lime-stones. Petrographic evidence and elemental values indicate that calcite was the original carbonate mineral in the limestones of the Ching-dar syncline. The elemental composition of the Ching-dar car-bonates also demonstrates that they have stabilized in a meteoric phreatic environment. Variation of Sr/Ca vs. Mn values suggests that diagenetic alteration occurred in an open geochemical system.

  15. Suburbanisation, homeownership aspirations and urban housing

    DEFF Research Database (Denmark)

    Andreasen, Manja Hoppe; Agergaard, Jytte; Møller-Jensen, Lasse

    2016-01-01

    . Urban residents settle in the periphery, even though incomegeneration is often tied to working somewhere else, namely in the central parts of the city. The paper proposes that the processes of urban expansion depicted in this study are usefully conceptualised as suburbanisation processes, though......This paper offers an exploration of urban expansion from the point of view of he individual residents buying land, settling and living in new, rapidly growing peripheral settlements of Dar es Salaam, Tanzania. The findings suggest that the demand for affordable housing is the primary motivation...

  16. A multi-dimensional assessment of urban vulnerability to climate change in Sub-Saharan Africa

    DEFF Research Database (Denmark)

    Herslund, Lise Byskov; Jalyer, Fatameh; Jean-Baptiste, Nathalie

    2016-01-01

    in Africa, which investigated climate change-induced risks, assessed vulnerability and proposed policy initiatives in five African cities. Dar es Salaam (Tanzania) was used as a main case with a particular focus on urban flooding. The multi-dimensional assessment covered the physical, institutional...... for strategic coordination and action. To better adapt to urban flooding andthereby reduce vulnerability and build resilience, we suggest working across dimensions and scales, integrating climate change issues in city-level plans and strategies and enabling local actions to initiate a ‘learning...

  17. Prevalence of post-traumatic stress disorder in children: the case of the Mbagala bomb blasts in Tanzania.

    Science.gov (United States)

    Messo, Innocent Nasson

    2013-05-01

    In April 2009, military bombs stockpiled in Mbagala, Dar es Salaam, exploded uncontrollably, landing in the neighbourhood killing 26 people, injuring about 600 and destroying 9049 homes. This must have been a terrible experience, with psychological consequences. The purpose of this study was to investigate the prevalence of Post-Traumatic Stress Disorder (PTSD) among the children involved in the bomb blasts. It was hypothesized that children would not exhibit PTSD symptoms, as well as not showing sex differences in exhibiting PTSD symptoms. The study findings show 93% of children bomb survivors had PTSD symptoms, with no sex differences in the PTSD reported.

  18. Discriminative ability of the generic and condition-specific Child-Oral Impacts on Daily Performances (Child-OIDP by the Limpopo-Arusha School Health (LASH Project: A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Masalu Joyce R

    2011-05-01

    Full Text Available Abstract Background Generic and condition-specific (CS oral-health-related quality-of-life (OHRQoL instruments assess the impacts of general oral conditions and specific oral diseases. Focusing schoolchildren from Arusha and Dar es Salaam, in Tanzania, this study compared the discriminative ability of the generic Child OIDP with respect to dental caries and periodontal problems across the study sites. Secondly, the discriminative ability of the generic-and the CS Child OIDP attributed to dental caries, periodontal problems and malocclusion was compared with respect to various oral conditions as part of a construct validation. Methods In Arusha, 1077 school children (mean age 14.9 years, range 12-17 years and 1601 school children in Dar es Salaam (mean age 13.0 years, range 12-14 years underwent oral clinical examinations and completed the Kiswahili version of the generic and CS Child-OIDP inventories. The discriminative ability was assessed as differences in overall mean and prevalence scores between groups, corresponding effect sizes and odd ratios, OR. Results The differences in the prevalence scores and the overall mean generic Child-OIDP scores were significant between the groups with (DMFT > 0 and without (DMFT = 0 caries experience and with (simplified oral hygiene index [OHI-S] > 1 and without periodontal problems (OHI-S ≤ 1 in Arusha and Dar es Salaam. In Dar es Salaam, differences in the generic and CS Child-OIDP scores were observed between the groups with and without dental caries, differences in the generic Child-OIDP scores were observed between the groups with and without periodontal problems, and differences in the CS Child-OIDP scores were observed between malocclusion groups. The adjusted OR for the association between dental caries and the CS Child-OIDP score attributed to dental caries was 5.4. The adjusted OR for the association between malocclusion and CS Child-OIDP attributed to malocclusion varied from 8.8 to 2

  19. 达累斯萨拉姆的供水与卫生:自助和可持续的技术

    Institute of Scientific and Technical Information of China (English)

    李晓隽

    2003-01-01

    The water supply and sanitation system in Dar es Salaam faU in awkward condition caused by severe waste, poor installment technology, inadequate coverage and maintenance and lack of modem sanitation models. Finding both central authorities technically and economicaUy unable to improve it, local citizen groups look for affordable ways of improving the necessary infrastructure through their own efforts. While their self-help initiatives have been successful, they urgently need support in information and technology for better solutions and proper use.

  20. Effects of LiDAR point density, sampling size and height threshold on estimation accuracy of crop biophysical parameters.

    Science.gov (United States)

    Luo, Shezhou; Chen, Jing M; Wang, Cheng; Xi, Xiaohuan; Zeng, Hongcheng; Peng, Dailiang; Li, Dong

    2016-05-30

    Vegetation leaf area index (LAI), height, and aboveground biomass are key biophysical parameters. Corn is an important and globally distributed crop, and reliable estimations of these parameters are essential for corn yield forecasting, health monitoring and ecosystem modeling. Light Detection and Ranging (LiDAR) is considered an effective technology for estimating vegetation biophysical parameters. However, the estimation accuracies of these parameters are affected by multiple factors. In this study, we first estimated corn LAI, height and biomass (R2 = 0.80, 0.874 and 0.838, respectively) using the original LiDAR data (7.32 points/m2), and the results showed that LiDAR data could accurately estimate these biophysical parameters. Second, comprehensive research was conducted on the effects of LiDAR point density, sampling size and height threshold on the estimation accuracy of LAI, height and biomass. Our findings indicated that LiDAR point density had an important effect on the estimation accuracy for vegetation biophysical parameters, however, high point density did not always produce highly accurate estimates, and reduced point density could deliver reasonable estimation results. Furthermore, the results showed that sampling size and height threshold were additional key factors that affect the estimation accuracy of biophysical parameters. Therefore, the optimal sampling size and the height threshold should be determined to improve the estimation accuracy of biophysical parameters. Our results also implied that a higher LiDAR point density, larger sampling size and height threshold were required to obtain accurate corn LAI estimation when compared with height and biomass estimations. In general, our results provide valuable guidance for LiDAR data acquisition and estimation of vegetation biophysical parameters using LiDAR data.

  1. El blanco ¿es un color?

    OpenAIRE

    López Sancho, José María; Gómez Díaz, Mª José; Cejudo Rodríguez, Salomé; Moreno Gómez, Esteban; López Álvarez, J.M.; Martínez de Andrés, Alejandro

    2013-01-01

    Película de dibujos animados como recurso educativo del Portal WEB KIDS.CSIC. Duración: 8 minutos y 25 segundos. Formato: FLV LOW RESOLUTION VIDEO, FOR HIGH RESOLUTION VISIT: http://www.kids.csic.es/cuentos/cuentos.html

  2. [Estimating individual tree aboveground biomass of the mid-subtropical forest using airborne LiDAR technology].

    Science.gov (United States)

    Liu, Feng; Tan, Chang; Lei, Pi-Feng

    2014-11-01

    Taking Wugang forest farm in Xuefeng Mountain as the research object, using the airborne light detection and ranging (LiDAR) data under leaf-on condition and field data of concomitant plots, this paper assessed the ability of using LiDAR technology to estimate aboveground biomass of the mid-subtropical forest. A semi-automated individual tree LiDAR cloud point segmentation was obtained by using condition random fields and optimization methods. Spatial structure, waveform characteristics and topography were calculated as LiDAR metrics from the segmented objects. Then statistical models between aboveground biomass from field data and these LiDAR metrics were built. The individual tree recognition rates were 93%, 86% and 60% for coniferous, broadleaf and mixed forests, respectively. The adjusted coefficients of determination (R(2)adj) and the root mean squared errors (RMSE) for the three types of forest were 0.83, 0.81 and 0.74, and 28.22, 29.79 and 32.31 t · hm(-2), respectively. The estimation capability of model based on canopy geometric volume, tree percentile height, slope and waveform characteristics was much better than that of traditional regression model based on tree height. Therefore, LiDAR metrics from individual tree could facilitate better performance in biomass estimation.

  3. Flood Risk Mapping Using LiDAR for Annapolis Royal, Nova Scotia, Canada

    Directory of Open Access Journals (Sweden)

    Tim L. Webster

    2010-09-01

    Full Text Available A significant portion of the Canadian Maritime coastline has been surveyed with airborne Light Detection and Ranging (LiDAR. The purpose of these surveys has been to map the risk of flooding from storm surges and projected long-term sea‑level rise from climate change and to include projects in all three Maritime Provinces: Prince Edward Island, New Brunswick, and Nova Scotia. LiDAR provides the required details in order to map the flood inundation from 1 to 2 m storm surge events, which cause coastal flooding in many locations in this region when they occur at high tide levels. The community of Annapolis Royal, Nova Scotia, adjacent to the Bay of Fundy, has been surveyed with LiDAR and a 1 m DEM (Digital Elevation Model was constructed for the flood inundation mapping. Validation of the LiDAR using survey grade GPS indicates a vertical accuracy better than 30 cm. A benchmark storm, known as the Groundhog Day storm (February 1–3, 1976, was used to assess the flood maps and to illustrate the effects of different sea-level rise projections based on climate change scenarios if it were to re-occur in 100 years time. Near shore bathymetry has been merged with the LiDAR and local wind observations used to model the impact of significant waves during this benchmark storm. Long-term (ca. greater than 30 years time series of water level observations from across the Bay of Fundy in Saint John, New Brunswick, have been used to estimate return periods of water levels under present and future sea-level rise conditions. Results indicate that under current sea-level rise conditions this storm has a 66 year return period. With a modest relative sea-level (RSL rise of 80 cm/century this decreases to 44 years and, with a possible upper limit rise of 220 cm/century, this decreases further to 22 years. Due to the uncertainty of climate change scenarios and sea-level rise, flood inundation maps have been constructed at 10 cm increments up to the 9 m contour

  4. Mobile LiDAR Measurement for Aerosol Investigation in South-Central Hebei, China

    Science.gov (United States)

    qin, kai; Wu, Lixin; Zheng, Yunhui; Wong Man, Sing; Wang, Runfeng; Hu, Mingyu; Lang, Hongmei; Wang, Luyao; Bai, Yang; Rao, Lanlan

    2016-04-01

    With the rapid industrialization and urbanization in China during the last decades, the increasing anthropogenic pollutant emissions have significantly caused serious air pollution problems which are adversely influencing public health. Hebei is one of the most air polluted provinces in China. In January 2013, an extremely severe and persistent haze episode with record-breaking PM2.5 outbreak affecting hundreds of millions of people occurred over eastern and northern China. During that haze episode, 7 of the top 10 most polluted cities in China were located in the Hebei Province according to the report of China's Ministry of Environmental Protection. To investigate and the spatial difference and to characterize the vertical distribution of aerosol in different regions of south-central Hebei, mobile measurements were carried out using a mini micro pulse LiDAR system (model: MiniMPL) in March 2014. The mobile LiDAR kit consisting of a MiniMPL, a vibration reduction mount, a power inverter, a Windows surface tablet and a GPS receiver were mounted in a car watching though the sunroof opening. For comparison, a fixed measurement using a traditional micro pulse LiDAR system (model: MPL-4B) was conducted simultaneously in Shijiazhuang, the capital of Hebei Province. The equipped car was driven from downtown Shijiazhuang by way of suburban and rural area to downtown Cangzhou, Handan, and Baoding respectively at almost stable speed around 100Km per hour along different routes which counted in total more than 1000Km. The results can be summarized as: 1) the spatial distribution of total aerosol optical depth along the measurement routes in south-central Hebei was controlled by local terrain and population in general, with high values in downtown and suburban in the plain areas, and low values in rural areas along Taihang mountain to the west and Yan mountain to the north; 2) obviously high AODs were obtained at roads crossing points, inside densely populated area and nearby

  5. Fusion of Airborne Discrete-Return LiDAR and Hyperspectral Data for Land Cover Classification

    Directory of Open Access Journals (Sweden)

    Shezhou Luo

    2015-12-01

    Full Text Available Accurate land cover classification information is a critical variable for many applications. This study presents a method to classify land cover using the fusion data of airborne discrete return LiDAR (Light Detection and Ranging and CASI (Compact Airborne Spectrographic Imager hyperspectral data. Four LiDAR-derived images (DTM, DSM, nDSM, and intensity and CASI data (48 bands with 1 m spatial resolution were spatially resampled to 2, 4, 8, 10, 20 and 30 m resolutions using the nearest neighbor resampling method. These data were thereafter fused using the layer stacking and principal components analysis (PCA methods. Land cover was classified by commonly used supervised classifications in remote sensing images, i.e., the support vector machine (SVM and maximum likelihood (MLC classifiers. Each classifier was applied to four types of datasets (at seven different spatial resolutions: (1 the layer stacking fusion data; (2 the PCA fusion data; (3 the LiDAR data alone; and (4 the CASI data alone. In this study, the land cover category was classified into seven classes, i.e., buildings, road, water bodies, forests, grassland, cropland and barren land. A total of 56 classification results were produced, and the classification accuracies were assessed and compared. The results show that the classification accuracies produced from two fused datasets were higher than that of the single LiDAR and CASI data at all seven spatial resolutions. Moreover, we find that the layer stacking method produced higher overall classification accuracies than the PCA fusion method using both the SVM and MLC classifiers. The highest classification accuracy obtained (OA = 97.8%, kappa = 0.964 using the SVM classifier on the layer stacking fusion data at 1 m spatial resolution. Compared with the best classification results of the CASI and LiDAR data alone, the overall classification accuracies improved by 9.1% and 19.6%, respectively. Our findings also demonstrated that the

  6. LiDAR Sampling Density for Forest Resource Inventories in Ontario, Canada

    Directory of Open Access Journals (Sweden)

    Dave Etheridge

    2012-03-01

    Full Text Available Over the past two decades there has been an abundance of research demonstrating the utility of airborne light detection and ranging (LiDAR for predicting forest biophysical/inventory variables at the plot and stand levels. However, to date there has been little effort to develop a set of protocols for data acquisition and processing that would move governments or the forest industry towards cost-effective implementation of this technology for strategic and tactical (i.e., operational forest resource inventories. The goal of this paper is to initiate this process by examining the significance of LiDAR data acquisition (i.e., point density for modeling forest inventory variables for the range of species and stand conditions representing much of Ontario, Canada. Field data for approximately 200 plots, sampling a broad range of forest types and conditions across Ontario, were collected for three study sites. Airborne LiDAR data, characterized by a mean density of 3.2 pulses m−2 were systematically decimated to produce additional datasets with densities of approximately 1.6 and 0.5 pulses m−2. Stepwise regression models, incorporating LiDAR height and density metrics, were developed for each of the three LiDAR datasets across a range of forest types to estimate the following forest inventory variables: (1 average height (R2(adj = 0.75–0.95; (2 top height (R2(adj = 0.74–0.98; (3 quadratic mean diameter (R2(adj = 0.55–0.85; (4 basal area (R2(adj = 0.22–0.93; (5 gross total volume (R2(adj = 0.42–0.94; (6 gross merchantable volume (R2(adj = 0.35–0.93; (7 total aboveground biomass (R2(adj = 0.23–0.93; and (8 stem density (R2(adj = 0.17–0.86. Aside from a few cases (i.e., average height and density for some stand types, no decimation effect was observed with respect to the precision of the prediction of the majority of forest variables, which suggests that a mean density of 0.5 pulses m−2 is sufficient for plot and stand level

  7. LESTO: an Open Source GIS-based toolbox for LiDAR analysis

    Science.gov (United States)

    Franceschi, Silvia; Antonello, Andrea; Tonon, Giustino

    2015-04-01

    During the last five years different research institutes and private companies stared to implement new algorithms to analyze and extract features from LiDAR data but only a few of them also created a public available software. In the field of forestry there are different examples of software that can be used to extract the vegetation parameters from LiDAR data, unfortunately most of them are closed source (even if free), which means that the source code is not shared with the public for anyone to look at or make changes to. In 2014 we started the development of the library LESTO (LiDAR Empowered Sciences Toolbox Opensource): a set of modules for the analysis of LiDAR point cloud with an Open Source approach with the aim of improving the performance of the extraction of the volume of biomass and other vegetation parameters on large areas for mixed forest structures. LESTO contains a set of modules for data handling and analysis implemented within the JGrassTools spatial processing library. The main subsections are dedicated to 1) preprocessing of LiDAR raw data mainly in LAS format (utilities and filtering); 2) creation of raster derived products; 3) flight-lines identification and normalization of the intensity values; 4) tools for extraction of vegetation and buildings. The core of the LESTO library is the extraction of the vegetation parameters. We decided to follow the single tree based approach starting with the implementation of some of the most used algorithms in literature. These have been tweaked and applied on LiDAR derived raster datasets (DTM, DSM) as well as point clouds of raw data. The methods range between the simple extraction of tops and crowns from local maxima, the region growing method, the watershed method and individual tree segmentation on point clouds. The validation procedure consists in finding the matching between field and LiDAR-derived measurements at individual tree and plot level. An automatic validation procedure has been developed

  8. Buildings classification from airborne LiDAR point clouds through OBIA and ontology driven approach

    Science.gov (United States)

    Tomljenovic, Ivan; Belgiu, Mariana; Lampoltshammer, Thomas J.

    2013-04-01

    In the last years, airborne Light Detection and Ranging (LiDAR) data proved to be a valuable information resource for a vast number of applications ranging from land cover mapping to individual surface feature extraction from complex urban environments. To extract information from LiDAR data, users apply prior knowledge. Unfortunately, there is no consistent initiative for structuring this knowledge into data models that can be shared and reused across different applications and domains. The absence of such models poses great challenges to data interpretation, data fusion and integration as well as information transferability. The intention of this work is to describe the design, development and deployment of an ontology-based system to classify buildings from airborne LiDAR data. The novelty of this approach consists of the development of a domain ontology that specifies explicitly the knowledge used to extract features from airborne LiDAR data. The overall goal of this approach is to investigate the possibility for classification of features of interest from LiDAR data by means of domain ontology. The proposed workflow is applied to the building extraction process for the region of "Biberach an der Riss" in South Germany. Strip-adjusted and georeferenced airborne LiDAR data is processed based on geometrical and radiometric signatures stored within the point cloud. Region-growing segmentation algorithms are applied and segmented regions are exported to the GeoJSON format. Subsequently, the data is imported into the ontology-based reasoning process used to automatically classify exported features of interest. Based on the ontology it becomes possible to define domain concepts, associated properties and relations. As a consequence, the resulting specific body of knowledge restricts possible interpretation variants. Moreover, ontologies are machinable and thus it is possible to run reasoning on top of them. Available reasoners (FACT++, JESS, Pellet) are used to check

  9. Monitoring Depth of Shallow Atmospheric Boundary Layer to Complement LiDAR Measurements Affected by Partial Overlap

    Directory of Open Access Journals (Sweden)

    Sandip Pal

    2014-09-01

    Full Text Available There is compelling evidence that the incomplete laser beam receiver field-of-view overlap (i.e., partial overlap of ground-based vertically-pointing aerosol LiDAR restricts the observational range for detecting aerosol layer boundaries to a certain height above the LiDAR. This height varies from one to few hundreds of meters, depending on the transceiver geometry. The range, or height of full overlap, is defined as the minimum distance at which the laser beam is completely imaged onto the detector through the field stop in the receiver optics. Thus, the LiDAR signal below the height of full overlap remains erroneous. In effect, it is not possible to derive the atmospheric boundary layer (ABL top (zi below the height of full overlap using lidar measurements alone. This problem makes determination of the nocturnal zi almost impossible, as the nocturnal zi is often lower than the minimum possible retrieved height due to incomplete overlap of lidar. Detailed studies of the nocturnal boundary layer or of variability of low zi would require changes in the LiDAR configuration such that a complete transceiver overlap could be achieved at a much lower height. Otherwise, improvements in the system configuration or deployment (e.g., scanning LiDAR are needed. However, these improvements are challenging due to the instrument configuration and the need for Raman channel signal, eye-safe laser transmitter for scanning deployment, etc. This paper presents a brief review of some of the challenges and opportunities in overcoming the partial overlap of the LiDAR transceiver to determine zi below the height of full-overlap using complementary approaches to derive low zi. A comprehensive discussion focusing on four different techniques is presented. These are based on the combined (1 ceilometer and LiDAR; (2 tower-based trace gas (e.g., CO2 concentration profiles and LiDAR measurements; (3 222Rn budget approach and LiDAR-derived results; and (4 encroachment model

  10. Diplomacia cultural. ¿Qué es y qué no es?

    OpenAIRE

    Fabiola Rodríguez Barba

    2015-01-01

    En las últimas décadas, el estudio de la diplomacia cultural ha sido (salvo excepciones) un tema poco estudiado, especialmente en América Latina. De ahí que en relación con la diplomacia cultural se habla mucho y se escribe poco. Aún más, lo que se escribe sobre ella más que esclarecer el tema lo oscurece. En ese sentido, el artículo tiene como propósito precisar qué es y qué no es la diplomacia cultural. Es decir, expone los objetivos, acciones y estrategias que caracterizan a la diplomacia ...

  11. Relatório de Estágio Curricular - Banco Espírito Santo (Guimarães)

    OpenAIRE

    Baptista, Bruna

    2012-01-01

    De acordo com o programa curricular do curso de Gestão da Escola Superior de Tecnologia e Gestão do Instituto Politécnico da Guarda, os alunos têm de realizar um estágio curricular ao qual está associada a elaboração de um relatório. Este é o fruto do meu estágio efetuado no Banco Espírito Santo, no balcão de Guimarães Sul, decorrido entre 16 de Agosto e 11 de Novembro de 2011. O presente relatório tem por finalidade dar a conhecer a instituição bancária, o local e as atividades desenvolvi...

  12. Zivilgesellschaft. Was kann und soll es bedeuten?

    OpenAIRE

    Pauer-Studer, Herlinde

    2002-01-01

    Es war auf einer Konferenz im September 2000 in London, einer Konferenz über feministische Bioethik. Eine kanadische Kollegin hielt einen Vortrag, in dem sie mit Hilfe der geometrischen Figur der Fraktale, jener komplexen Dreiecksstrukturen, die angeblich den strukturellen Aufbau aller Entitäten bestimmen, das Wesen der Schwangerschaftsbeziehung zu erklären versuchte, also jener Beziehung, die angeblich mehr als eines und weniger als zwei umfasst. Die Reaktionen auf den Vortrag...

  13. Un correveidile no es un periodista

    Directory of Open Access Journals (Sweden)

    Pedro Pérez Cuadrado

    2013-09-01

    Full Text Available Un acercamiento a la obra 'Periodismo es preguntar' del catedrático de la Universidad de La Laguna José Manuel de Pablos Coello, quien, con ejemplos extraídos de la actualidad diaria, consigue un prontuario deontológico de la información periodística pegado al sentido común y con una fuerte base en experiencias profesionales propias.

  14. ¿Qué es conducta?

    Directory of Open Access Journals (Sweden)

    Esteve Freixa i Baqué

    2003-01-01

    Full Text Available La definición de la Psicología como ciencia de la conducta adoptada por el Conductismo supone e implica a su vez una conceptualización clara y unívoca de dicho concepto. Pero tal definición se enfrenta con una serie de malentendidos tenaces que dificultan no sólo la comprensión de dicho concepto básico sino también, en consecuencia, la propia conceptualización conductista. El propósito del presente trabajo es intentar exponer algunos de estos malentendidos, entre los que destacan los errores categoriales groseros, los procesos de reificación abusiva, los razonamientos tautológicos disfrazados, la generalización imprudente del modelo médico al ámbito de la conducta y la confusión nefasta entre un fenómeno y su conceptualización. Para ello, y con un tono más didáctico que académico, se recurre a una serie de metáforas de la vida cotidiana: la parte escondida del iceberg no es más que iceberg, las piedras no caen por su propio peso, los hombres y las mujeres no mueren porque son mortales, el bacilo de Koch existe y la máscara no es el rostro.

  15. ¿Es la ocratoxina a una micotoxina mutagénica?

    Directory of Open Access Journals (Sweden)

    L. Arbillaga

    2004-01-01

    Full Text Available La ocratoxina A es una micotoxina producida por especies de los géneros Aspergillus y Penicillium que a través de los alimentos puede pasar al ser humano. Su órgano diana es el riñón pero también es hepatotóxica, inmunotóxica y teratogénica. Ha sido clasificada por la Agencia Internacional de Investigación contra el Cáncer (IARC como posible carcinógeno humano (clase 2B pero se desconoce si el mecanismo de acción transcurre a través de fenómenos genéticos o epigenéticos. En este artículo se revisan los datos de genotoxicidad y mutagenicidad de esta micotoxina. Aunque los primeros estudios en ensayos de reversión mutagénica con bacterias resultaron negativos, pronto se comprobó que administrada a animales de experimentación, la ocratoxina A inducía la formación de aductos especialmente en tejidos de riñón y vejiga urinaria de ratón. También se ha comprobado que esta micotoxina produce roturas monocatenarias en el ADN, da lugar a alteraciones cromosómicas e intercambios entre cromátidas hermanas e induce la síntesis de ADN fuera del período S, fenómeno indicativo de procesos de reparación. Se considera que la actividad genotóxica es dependiente de activación metabólica, en particular de varias isoformas P450, si bien los metabolitos genotóxicos no han sido aislados. Los últimos estudios realizados con ocratoxina A tritiada bajo diversas condiciones experimentales indican que el principal metabolito es el derivado monohidroxilado 4- (R – hidroxi-ocratoxina A y que ni la ocratoxina A ni este metabolito forman aductos con el ADN, por lo que su actividad genotóxica estaría más relacionada con procesos de citotoxicidad y peroxidación lipídica, los cuales podrían dar lugar a moléculas reactivas con los ácidos nucleicos

  16. Quantifying soil carbon loss and uncertainty from a peatland wildfire using multi-temporal LiDAR

    Science.gov (United States)

    Reddy, Ashwan D.; Hawbaker, Todd J.; Wurster, F.; Zhu, Zhiliang; Ward, S.; Newcomb, Doug; Murray, R.

    2015-01-01

    Peatlands are a major reservoir of global soil carbon, yet account for just 3% of global land cover. Human impacts like draining can hinder the ability of peatlands to sequester carbon and expose their soils to fire under dry conditions. Estimating soil carbon loss from peat fires can be challenging due to uncertainty about pre-fire surface elevations. This study uses multi-temporal LiDAR to obtain pre- and post-fire elevations and estimate soil carbon loss caused by the 2011 Lateral West fire in the Great Dismal Swamp National Wildlife Refuge, VA, USA. We also determine how LiDAR elevation error affects uncertainty in our carbon loss estimate by randomly perturbing the LiDAR point elevations and recalculating elevation change and carbon loss, iterating this process 1000 times. We calculated a total loss using LiDAR of 1.10 Tg C across the 25 km2 burned area. The fire burned an average of 47 cm deep, equivalent to 44 kg C/m2, a value larger than the 1997 Indonesian peat fires (29 kg C/m2). Carbon loss via the First-Order Fire Effects Model (FOFEM) was estimated to be 0.06 Tg C. Propagating the LiDAR elevation error to the carbon loss estimates, we calculated a standard deviation of 0.00009 Tg C, equivalent to 0.008% of total carbon loss. We conclude that LiDAR elevation error is not a significant contributor to uncertainty in soil carbon loss under severe fire conditions with substantial peat consumption. However, uncertainties may be more substantial when soil elevation loss is of a similar or smaller magnitude than the reported LiDAR error.

  17. Analysis of elevation changes detected from multi-temporal LiDAR surveys in forested landslide terrain in western Oregon

    Science.gov (United States)

    Burns, W.J.; Coe, J.A.; Kaya, B.S.; Ma, L.

    2010-01-01

    We examined elevation changes detected from two successive sets of Light Detection and Ranging (LiDAR) data in the northern Coast Range of Oregon. The first set of LiDAR data was acquired during leafon conditions and the second set during leaf-off conditions. We were able to successfully identify and map active landslides using a differential digital elevation model (DEM) created from the two LiDAR data sets, but this required the use of thresholds (0.50 and 0.75 m) to remove noise from the differential elevation data, visual pattern recognition of landslideinduced elevation changes, and supplemental QuickBird satellite imagery. After mapping, we field-verified 88 percent of the landslides that we had mapped with high confidence, but we could not detect active landslides with elevation changes of less than 0.50 m. Volumetric calculations showed that a total of about 18,100 m3 of material was missing from landslide areas, probably as a result of systematic negative elevation errors in the differential DEM and as a result of removal of material by erosion and transport. We also examined the accuracies of 285 leaf-off LiDAR elevations at four landslide sites using Global Positioning System and total station surveys. A comparison of LiDAR and survey data indicated an overall root mean square error of 0.50 m, a maximum error of 2.21 m, and a systematic error of 0.09 m. LiDAR ground-point densities were lowest in areas with young conifer forests and deciduous vegetation, which resulted in extensive interpolations of elevations in the leaf-on, bare-earth DEM. For optimal use of multi-temporal LiDAR data in forested areas, we recommend that all data sets be flown during leaf-off seasons.

  18. Horizontal geometrical reaction time model for two-beam nacelle LiDARs

    Science.gov (United States)

    Beuth, Thorsten; Fox, Maik; Stork, Wilhelm

    2015-06-01

    Wind energy is one of the leading sustainable energies. To attract further private and state investment in this technology, a broad scaled drop of the cost of energy has to be enforced. There is a trend towards using Laser Doppler Velocimetry LiDAR systems for enhancing power output and minimizing downtimes, fatigue and extreme forces. Since most used LiDARs are horizontally setup on a nacelle and work with two beams, it is important to understand the geometrical configuration which is crucial to estimate reaction times for the actuators to compensate wind gusts. In the beginning of this article, the basic operating modes of wind turbines are explained and the literature on wind behavior is analyzed to derive specific wind speed and wind angle conditions in relation to the yaw angle of the hub. A short introduction to the requirements for the reconstruction of the wind vector length and wind angle leads to the problem of wind shear detection of angled but horizontal homogeneous wind fronts due to the spatial separation of the measuring points. A distance is defined in which the wind shear of such homogeneous wind fronts is not present which is used as a base to estimate further distance calculations. The reaction time of the controller and the actuators are having a negative effect on the effective overall reaction time for wind regulation as well. In the end, exemplary calculations estimate benefits and disadvantages of system parameters for wind gust regulating LiDARs for a wind turbine of typical size. An outlook shows possible future improvements concerning the vertical wind behavior.

  19. Investigation on the contribution of LiDAR data in 3D cadastre

    Science.gov (United States)

    Giannaka, Olga; Dimopoulou, Efi; Georgopoulos, Andreas

    2014-08-01

    The existing 2D cadastral systems worldwide cannot provide a proper registration and representation of the land ownership rights, restrictions and responsibilities in a 3D context, which appear in our complex urban environment. Ιn such instances, it may be necessary to consider the development of a 3D Cadastre in which proprietary rights acquire appropriate three-dimensional space both above and below conventional ground level. Such a system should contain the topology and the coordinates of the buildings' outlines and infrastructure. The augmented model can be formed as a full 3D Cadastre, a hybrid Cadastre or a 2D Cadastre with 3D tags. Each country has to contemplate which alternative is appropriate, depending on the specific situation, the legal framework and the available technical means. In order to generate a 3D model for cadastral purposes, a system is required which should be able to exploit and represent 3D data such as LiDAR, a remote sensing technology which acquires three-dimensional point clouds that describe the earth's surface and the objects on it. LiDAR gives a direct representation of objects on the ground surface and measures their coordinates by analyzing the reflecting light. Moreover, it provides very accurate position and height information, although direct information about the objects' geometrical shape is not conveyed. In this study, an experimental implementation of 3D Cadastre using LiDAR data is developed, in order to investigate if this information can satisfy the specifications that are set for the purposes of the Hellenic Cadastre. GIS tools have been used for analyzing DSM and true orthophotos of the study area. The results of this study are presented and evaluated in terms of usability and efficiency.

  20. High-Resolution LiDAR Topography of the Plate-Boundary Faults in Northern California

    Science.gov (United States)

    Prentice, C. S.; Phillips, D. A.; Furlong, K. P.; Brown, A.; Crosby, C. J.; Bevis, M.; Shrestha, R.; Sartori, M.; Brocher, T. M.; Brown, J.

    2007-12-01

    GeoEarthScope acquired more than 1500 square km of airborne LiDAR data in northern California, providing high-resolution topographic data of most of the major strike-slip faults in the region. The coverage includes the San Andreas Fault from its northern end near Shelter Cove to near Parkfield, as well as the Rodgers Creek, Maacama, Calaveras, Green Valley, Paicines, and San Gregorio Faults. The Hayward fault was added with funding provided by the US Geological Survey, the City of Berkeley, and the San Francisco Public Utilities Commission. Data coverage is typically one kilometer in width, centered on the fault. In areas of particular fault complexity the swath width was increased to two kilometers, and in selected areas swath width is as wide as five kilometers. A five-km-wide swath was flown perpendicular to the plate boundary immediately south of Cape Mendocino to capture previously unidentified faults and to understand off-fault deformation associated with the transition zone between the transform margin and the Cascadia subduction zone. The data were collected in conjunction with an intensive GPS campaign designed to improve absolute data accuracy and provide quality control. Data processing to classify the LiDAR point data by return type allows users to filter out vegetation and produce high-resolution DEMs of the ground surface beneath forested regions, revealing geomorphic features along and adjacent to the faults. These data will allow more accurate mapping of fault traces in regions where the vegetation canopy has hampered this effort in the past. In addition, the data provide the opportunity to locate potential sites for detailed paleoseismic studies aimed at providing slip rates and event chronologies. The GeoEarthScope LiDAR data will be made available via an interactive data distribution and processing workflow currently under development.