WorldWideScience

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. 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.

  3. 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.

  4. 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

  5. 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.

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

    OpenAIRE

    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 Salaam region. Urban and peri-urban smallholder dairying is viewed as an agricultural activity that provides a regular and stable income to the household and is considered to be a forerunner of further ...

  7. 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…

  8. 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…

  9. 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),

  10. 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),

  11. Potential of solar power in electricity production in Dar es Salaam, Tanzania : focus on households and paybacks

    OpenAIRE

    Kibbassa, Mwilumbwa

    2010-01-01

    The purpose of this work was to study the opportunities and challenges of using solar power by solar photovoltaic (PV) in production of electricity for households in Dar es Salaam, Tanzania. Dar es Salaam has plenty of sunshine throughout the year making it a perfect candidate for solar PV electrification. Data collected for this work was done mainly by conducting interviews with different levels of households, private and government institutes, literature from books, web pages and previou...

  12. 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...... the ages of 25--59 who lived in the sampled streets were invited to a cervical cancer screening; 804 women accepted and 313 rejected the invitation. Information on demographic characteristics and knowledge of cervical cancer were obtained through structured questionnaire interviews. RESULTS: Women aged 35...... to accept screening in comparison with women who had five or more children (ORs 3.21). Finally, knowledge of cervical cancer and awareness of the existing screening program were also associated with increased acceptance rates (ORs of 5.90 and 4.20). CONCLUSION: There are identifiable subgroups where...

  13. Urban lymphatic filariasis in the metropolis of Dar es Salaam, Tanzania

    OpenAIRE

    Mwakitalu, Mbutolwe E; Malecela, Mwelecele N.; Pedersen, Erling M; Franklin W Mosha; Paul E Simonsen

    2013-01-01

    Background The last decades have seen a considerable increase in urbanization in Sub-Saharan Africa, and it is estimated that over 50% of the population will live in urban areas by 2040. Rapid growth of cities combined with limited economic resources often result in informal settlements and slums with favorable conditions for proliferation of vectors of lymphatic filariasis (LF). In Dar es Salaam, which has grown more than 30 times in population during the past 55 years (4.4 million inhabitan...

  14. IMPROVING SOLID WASTE MANAGEMENT IN THE DAR ES SALAAM COASTAL BELT, TANZANIA

    OpenAIRE

    Maziku, John

    2014-01-01

    The aim of the study was to understand the factors which influence the state of solid waste management in the Dar es Salaam Coastal Belt, Tanzania. The research used semi-structured and structured interviews, group discussions, field observations and review of various literatures as the major methods of the study. Questionnaires were used for interviews. Results showed poor community awareness (except students and beach goers) of solid waste management and its significance; and...

  15. Towards sustainable ground water management in Dar Es Salaam city, Tanzania

    International Nuclear Information System (INIS)

    Groundwater pollution in urban areas is a worldwide growing environmental problem in this millennium. Many major cities in the world depend on groundwater for water supplies. However, urbanization processes threaten its quality. The problem is more pronounced in urban areas in developing countries like Tanzania, which are characterized with inadequate infrastructure for waste management. In Tanzania, the situation is more threatening in Dar Es Salaam City, which experiences acute deficiency in infrastructure provision: housing, water supply, sanitation, transportation and energy. The existing challenge is to protect groundwater resources amidst rapid growing Dar Es Salaam city, of which failure can lead to escalating costs for provision of drinking water with overall results of decreased public health conditions. A research conducted from 1997 to 2002, revealed that almost 50% of the water supply in Dar Es Salaam city comes from groundwater and that groundwater is being threatened by indiscriminate disposal practices of both domestic and industrial wastes. For example about 88% of the urban population use on-site sanitation systems, which discharge partially treated sewage to the groundwater. About 60 tonnes/day of chemical oxygen demand (COD) are transported to the groundwater through domestic sewage. Analysis of groundwater quality in the city indicated that the unconfined aquifer is starting to degrade. For instance, more than 40% of groundwater samples analysed for nitrate, chloride and faecal coliform bacteria, did not comply with the national standards for drinking water. Recognising the fact that demand for groundwater is on the increase in the city and that the aquifers have shown signs of degradation, a groundwater management plan is required to ensure sustainable utilization of the resource. This paper discusses the groundwater situation in Dar Es Salaam city and finally puts forward measures towards establishment of a management strategy. (author)

  16. 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.

  17. 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

  18. Residents’ perceptions of institutional performance in water supply in Dar es Salaam

    Science.gov (United States)

    Mwakalila, Shadrack

    This paper addresses the performance of institutions in water supply systems for improving social and economic benefits of people living in Dar es Salaam city. The methods employed in field data and information collection included interviews, questionnaire, focus group discussions and participatory observation. Kinondoni and Ilala Districts were used as case study. The study revealed that, the main water sources in the study areas are boreholes, shallow wells, rain water and water vendors. Other minor sources are piped water and natural water sources, such as rivers and streams. The supply of piped water by Dar es Salaam Water Sewerage and Sanitation Company (DAWASA/DAWASCO) meets only 45% of the total water demands. Individuals own and sell water from boreholes, shallow wells, piped water connected to their individual houses and natural wells located in their individual plots. The price of one 20 l bucket of water from a water vendor depends on the availability of water and the distance walked from the water source to the customer. Majority of the respondents (77.5%) indicated that individual water delivery systems provide sufficient water as compared to five years ago in the study areas. Few of the respondents (6.3%) said individual water delivery systems have no capacity to provide sufficient water while 16.3% indicate that individual water delivery systems provide moderate water supply but are important in supplementing other water providers in the study areas. The study reveals that a majority of the local population are satisfied with the capacity of individual water delivery systems in providing water for household uses. This paper recommends some improvements to be done to water supply systems in the Dar es Salaam city.

  19. 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

    The risk of flooding in urban areas could be better approached by complementing conventional sewer systems with sustainable urban drainage systems (SUDS) for storm-water management. This may be the case for developing world cities like Dar es Salaam with incomplete sewer services, as well as cities...... like Copenhagen with fully developed sewer systems. This paper explores some theories relevant to understanding how the implementation of SUDS may be one option for supporting a transition towards sustainable urban water management (SUWM). Using interviews, document analysis and observation...

  20. 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

    OBJECTIVE: To assess the need for post-abortion contraception and to determine if women who had an unsafe abortion will use a contraceptive method to avoid repeated unwanted pregnancies and STDs/HIV. METHOD: Women attending Temeke Municipal Hospital, Dar es Salaam, after an unsafe abortion...... 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...

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

    OpenAIRE

    Mohammed, Najat K.

    2012-01-01

    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 a...

  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. 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. PMID:24908469

  4. Family perceptions of intellectual disability: Understanding and support in Dar es Salaam

    Directory of Open Access Journals (Sweden)

    Heather M. Aldersey

    2012-05-01

    Full Text Available When attempting to understand the construct of intellectual disability in different contexts, speaking to family members in addition to the individual with the disability may provide new insight about understandings of and responses to intellectual disability in society and may help to identify the forms of support that are available or needed to ensure the quality of life of people with disabilities. This article outlines and discusses interviews that were conducted in Dar es Salaam, Tanzania, with family members of children and adults with intellectual disabilities. These interviews explore how families came to understand that their child had an intellectual disability; the availability of family support; and family hopes and dreams for the future, and were a part of a wider exploratory study that gathered insight from individuals with disabilities, families, and other providers of support to explore understandings and perceptions of disability in Dar es Salaam. Understanding family experiences will help researchers, policy makers, non-governmental organisations, and others to identify family strengths and family support needs which can ultimately improve family quality of life and the quality of life of the member with a disability.

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

    Directory of Open Access Journals (Sweden)

    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.

  6. 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

  7. Intimate Partner Violence and the Association with HIV Risk Behaviors among Young Men in Dar Es Salaam, Tanzania

    Science.gov (United States)

    Maman, Suzanne; Yamanis, Thespina; Kouyoumdjian, Fiona; Watt, Melissa; Mbwambo, Jessie

    2010-01-01

    There is growing evidence of the association between gender-based violence and HIV from the perspective and experiences of women. The purpose of this study is to examine these associations from the perspective of young men living in Dar es Salaam, Tanzania. A community-based sample of 951 men were interviewed, of whom 360 had sex in the past 6…

  8. Occupational exposure and health problems in small-scale industry workers in Dar es Salaam, Tanzania: a situation analysis.

    NARCIS (Netherlands)

    Rongo, L.M.B.; Barten, F.J.M.H.; Msamanga, G.I.; Heederik, D.; Dolmans, W.M.V.

    2004-01-01

    BACKGROUND: Workers in informal small-scale industries (SSI) in developing countries involved in welding, spray painting, woodwork and metalwork are exposed to various hazards with consequent risk to health. Aim To assess occupational exposure and health problems in SSI in Dar es Salaam, Tanzania. M

  9. Provision of Vocational Skills Education to Orphans: Lessons from Orphanage Centres in Dar es Salaam City, Tanzania

    Science.gov (United States)

    Meli, Benjamin Mbeba

    2015-01-01

    This paper utilises data from a study that investigated the efficacy of vocational skills training provided to orphans from three orphanages in Temeke District, Dar es Salaam. The three orphanage centres that were studied are Kurasini National Children Home, Saudia and Don Bosco Vocational Centre. The sample comprised of 45 orphans, an official…

  10. 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

  11. 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.

  12. 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

    screening program in Dar es Salaam in the period 2002 -- 2008. The women underwent VIA examination and took part in a structured questionnaire interview. Socioeconomic characteristics, sexual behavior, HIV status and high-risk (HR) HPV infection were determined in a subpopulation of 890 who participated...... participated in the screening were more likely to be HIV positive OR= 1.59 (95% CI. 1.14-2.25) in comparison with women who had never attended screening, while no difference was found in the prevalence of HR-HPV infection among women who had attended screening and women who had not attended screening...... screening program is in place in the setting studied, where HIV positive were more likely to participate in the cervical cancer screening program than HIV negative women....

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

    DEFF Research Database (Denmark)

    Yhdego, Michael

    1992-01-01

    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......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...... are described. Experiments revealed wastes from the market are readily decomposable by composting. A change in the design of covered markets and improvements in waste handling are essential to reduce the potential health hazards in developing countries....

  14. 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

    . 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...... to the conservation of existing urban agriculture and future initiatives. The findings suggest that municipal recognition and institutional support for urban agriculture is an important component in increasing the sustainability of related initiatives. Local and central government plays a role in the legitimization......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...

  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

    OBJECTIVE: To assess the need for post-abortion contraception and to determine if women who had an unsafe abortion will use a contraceptive method to avoid repeated unwanted pregnancies and STDs/HIV. METHOD: Women attending Temeke Municipal Hospital, Dar es Salaam, after an unsafe abortion...... 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......: High-quality contraceptive service counselling can induce women to use contraception after having had an unsafe abortion. The results of our study are encouraging and should be used to convince policy makers of the need to implement such services at municipal level to reduce the number of repeated...

  16. 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.

  17. 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."

  18. 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.

  19. 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...

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

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    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

  1. Urban lymphatic filariasis in the metropolis of Dar es Salaam, Tanzania

    Science.gov (United States)

    2013-01-01

    Background The last decades have seen a considerable increase in urbanization in Sub-Saharan Africa, and it is estimated that over 50% of the population will live in urban areas by 2040. Rapid growth of cities combined with limited economic resources often result in informal settlements and slums with favorable conditions for proliferation of vectors of lymphatic filariasis (LF). In Dar es Salaam, which has grown more than 30 times in population during the past 55 years (4.4 million inhabitants in 2012), previous surveys have indicated high prevalences of LF. This study investigated epidemiological aspects of LF in Dar es Salaam, as a background for planning and implementation of control. Methods Six sites with varying distance from the city center (3–30 km) and covering different population densities, socioeconomic characteristics, and water, sewerage and sanitary facilities were selected for the study. Pupils from one public primary school at each site were screened for circulating filarial antigen (CFA; marker of adult worm infection) and antibodies to Bm14 (marker of exposure to transmission). Community members were examined for CFA, microfilariae and chronic manifestations. Structured questionnaires were administered to pupils and heads of community households, and vector surveys were carried out in selected households. Results The study indicated that a tremendous decrease in the burden of LF infection had occurred, despite haphazard urbanisation. Contributing factors may be urban malaria control targeting Anopheles vectors, short survival time of the numerous Culex quinquefasciatus vectors in the urban environment, widespread use of bed nets and other mosquito proofing measures, and mass drug administration (MDA) in 2006 and 2007. Although the level of ongoing transmission was low, the burden of chronic LF disease was still high. Conclusions The development has so far been promising, but continued efforts are necessary to ensure elimination of LF as a

  2. 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...

  3. 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

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

    OpenAIRE

    Tumpale Sakijege; John Lupala; Shaaban Sheuya

    2012-01-01

    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 ...

  5. Stakeholder collaboration in community-based organizations (CBOs): The case of a sanitation CBO working in Dar es Salaam, Tanzania

    OpenAIRE

    Guzman Figueroa, Nathaly

    2015-01-01

    This thesis focuses on the study of the stakeholder relations of PHAST Ujenzi, a community-based organization (CBO) that provides sanitation services in a slum area of Dar es Salaam, Tanzania. My research aims at describing how this CBO has established and maintained relations with different stakeholders, and it looks for highlighting interests, benefits, and challenges in such collaborations. Additionally, my study aims at contributing to the Stakeholder Theory literature, by providing relev...

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

    OpenAIRE

    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 children (85%) in the case group attended the dental clinic because of crowding. Aesthetic impairment (AC grades 8-10) and severe malocclusions (DHC grades 4-5) were higher in cases than in controls b...

  7. Food habits of the blue swimming crab portunus pelagicus along the coast of Dar es Salaam, Tanzania

    OpenAIRE

    Mgaya, Y. D.; Chande, A.I.

    2004-01-01

    The food habits of the blue swimming crab Portunus pelagicus were investigated using the stomachs of 3948 crabs collected from Kunduchi sub-littoral shallow waters, Msasani Bay and Mzinga creek along the coast of Dar es Salaam. The main food items included mollusks (51.3%), crustaceans (24.1%), fish bones (18%) and unidentified food items (6.6%). The dominant food item was the bivalve Arcuatula arcuatula Hanley, 1844. Other molluscs included the gastropod genera Nassarius, Littoraria and Conu...

  8. Employees Opinions Towards the Information Technology Offered to Their Daily Firm’s Operation In Dar Es Salaam, Tanzania

    OpenAIRE

    Nelson Jagero; Wahid Bakari Hamad; Masese Chuma Benard

    2012-01-01

    There is widespread acceptance that IT is a central component of business operations and extensively used in marketing. Therefore, the major objective of the research was to assessing the impact that Information Technology (IT) has in influencing Dar es Salaam Small and Medium Manufacturing Enterprises (SMMEs) on marketing strategies so as to improve the marketing operations. Study findings revealed that, generally information technology has impacted positively on the SMMEs on performing thei...

  9. 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.

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

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    Marc C. A. Wegerif

    2014-06-01

    Full Text Available 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 seen as incapable of feeding the world’s growing and increasingly urban population. Since much of the world’s future population growth is going to happen in the cities of the developing world, they have become the frontline for the expansion of the industrial food system, raising the serious challenge of ensuring food security for residents. This paper, based on a qualitative study of patterns of egg provisioning in Dar es Salaam, explores whether existing patterns of food supply in this rapidly growing city, of over four million people, provide workable alternatives. Eggs are an important source of nutrition and patterns of egg supply offer a lens through which to explore the sustainability of different modes of provisioning. A range of non-corporate provisioning patterns, based on small-scale enterprises, are found to have social, economic and environmental advantages, challenging assumptions that corporate food chains are necessary, or desirable, to feed cities sustainably.

  11. 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.

  12. 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.

  13. 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.

  14. Characterization of Salmonella species from water bodies in Dar-Es-Salaam city, Tanzania

    Directory of Open Access Journals (Sweden)

    Eliningaya Kweka

    2013-01-01

    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.

  15. Skinning the goat and pulling the load: transactional sex among youth in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Maganja, R K; Maman, S; Groves, A; Mbwambo, J K

    2007-09-01

    Transactional sex has been associated with risk of HIV infection in a number of studies throughout sub-Saharan Africa. Urban young women are economically vulnerable and at heightened risk of HIV infection in Tanzania; yet there are few studies that have explored relationship dynamics, including transactional sex, in this setting. This paper sheds light on the broader context of sexual relationships among youth at risk for HIV, how transactional sex plays out in these relationships, and how the transactional nature of relationships affects women's risk for HIV. We conducted 60 in depth interviews and 14 focus group discussions with young men and women, 16-24 years old, in Dar es Salaam, Tanzania. These data guided the development of a community based HIV and violence prevention intervention for young men. Youth described the exchange of sex for money or other material goods in all types of sexual relationships. While the exchange was explicit in casual relationships, young women voiced material and monetary expectations from their committed partners as well. Young men described their pursuit of multiple partners as sexually motivated, while women sought multiple partners for economic reasons. Young men were aware of the expectations of material support from partners, and acknowledged that their ability to provide for a partner affected both the longevity and exclusivity of their relationships. Youth described a deep mistrust of the motivations and commitment of their sexual partners. Furthermore, young women's financial dependence on men impacted their ability to negotiate safe sexual behaviors in both casual and committed relationships. Programs designed to reduce HIV risk among Tanzanian youth need to take into account the transactional component of sexual relationships and how such exchanges differ according to partner type. PMID:17851993

  16. 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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  19. 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

  20. 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

  1. 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

  2. Prevalence of Overweight and Obesity among Primary School Children Aged 8–13 Years in Dar es Salaam City, Tanzania

    Science.gov (United States)

    Pangani, Ismail N.; Kiplamai, Festus K.; Kamau, Jane W.; Onywera, Vincent O.

    2016-01-01

    Background. The understanding of obesity as a growing health problem in Africa and Tanzania in particular is hampered by lack of data as well as sociocultural beliefs in which overweight and obesity are revered. This study sought to determine the prevalence of overweight and obesity among primary school children aged 8–13 years in Dar es Salaam, Tanzania. Method. A cross-sectional analytical research design was used to study overweight and obesity in primary schools in Dar es Salaam, Tanzania. The target population was 150,000 children aged 8–13 years. Stratified random sampling was used to select 1781 children. Weight and height were taken and WHO standards for children were used to determine weight status. Results. Findings showed that the prevalence of overweight and obesity was 15.9% and 6.7%, respectively (N = 1781). However, 6.2% of the children were underweight. There were significant differences in mean BMI between children in private and public schools (p = 0.021), between male and female (p obesity among primary school children is significant and requires management and prevention strategies.

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

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    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.

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

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    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

  5. 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

    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......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...

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

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    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

  7. 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...... 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...... 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

  8. 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

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

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    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

  10. 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

  11. Informality in the context of the urban spatial development of Dar es Salaam - A structural analysis of the development of the urban space

    OpenAIRE

    Stender, Kristian

    2015-01-01

    The thesis is concerned with examining the relation between the growing informal economy, expanding informal settlements in Dar es Salaam and examines the overall spatial development of the city. Fieldwork has been conducted as the point of departure of understanding the processes and structures influencing the urban development and the aspects of the informal economy and informal settlements. The fieldwork included semi-structured interviews with trade union officials, sporadic and structure...

  12. Utilization of cervical cancer screening services and its associated factors among primary school teachers in Ilala Municipality, Dar es Salaam, Tanzania

    OpenAIRE

    Kileo, Neema Minja; Michael, Denna; Neke, Nyasule Majura; Moshiro, Candida

    2015-01-01

    Background Worldwide cervical cancer is one of the more common forms of carcinoma among women, causing high morbidity and high mortality. Despite being a major health problem in Tanzania, screening services for cervical cancer are very limited, and uptake of those services is low. We therefore conducted a study to investigate utilization of cancer screening services, and its associated factors among female primary school teachers in Ilala Municipality, Dar es Salaam. Method We conducted a cro...

  13. 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.

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

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    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.

  15. Predictors of poor glycemic control in type 2 diabetic patients attending public hospitals in Dar es Salaam

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    Kamuhabwa AR

    2014-10-01

    Full Text Available Appolinary R Kamuhabwa, Emmanuel CharlesUnit of Pharmacology and Therapeutics, School of Pharmacy, Muhimbili University of Health and Allied Sciences, Dar es Salaam, TanzaniaBackground: Tanzania has recently experienced a significant rise in the burden of diabetes, and it is estimated that more than 400,000 people are living with diabetes. A major concern in the management of diabetes is the occurrence of diabetic complications that occur as a result of poor glycemic control. Identification of the factors associated with poor glycemic control is important in order to institute appropriate interventions for the purpose of improving glycemic control and prevention of chronic complications.Aim: The aim of this study was to determine the level of glycemic control and explore the factors associated with poor glycemic control among patients with type 2 diabetes mellitus (T2DM.Methodology: A cross-sectional study was carried out at the diabetic clinics for T2DM patients at the national and municipal hospitals in Dar es Salaam. A total of 469 patients were enrolled over a period of 8 weeks from March 2013 to May 2013. Patients' information such as sociodemographic characteristics, self-care management behaviors, and medication adherence were obtained through interviews. Blood pressure, weight, and height were measured during the day of the interview. All available last readings for fasting blood glucose (FBG measurements, lipid profile, and other clinical characteristics were obtained from patients' records.Results: The mean age of patients was 54.93 years. The majority (63.5% of patients were females and only eight patients had records of lipid profile measurements. Out of 469 patients, 69.7% had FBG of ≥7.2 mmol/L, indicating poor glycemic control. Females aged between 40 years and 59 years had significantly higher poor glycemic control (76.1% as compared with their male counterparts. Thirty-eight percent of patients had poor medication adherence

  16. Identifying programmatic gaps: inequities in harm reduction service utilization among male and female drug users in Dar es Salaam, Tanzania.

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    Barrot H Lambdin

    Full Text Available INTRODUCTION: Current estimates suggest an HIV prevalence of 42% among people who inject drugs (PWIDs in Dar es Salaam, while HIV prevalence is estimated to be 8.8% among the general population in the city. To address the HIV epidemic in this population, the government of Tanzania began establishing HIV prevention, treatment and care services including outreach and medication assisted treatment (MAT for PWIDs in 2010. We assessed gender inequities in utilization of outreach and MAT services and evaluated differences in HIV risk behaviors between female and male PWIDs. MATERIALS AND METHODS: Routine outreach data between December 2010 to mid-August 2012 and baseline data on clients enrolling in methadone from February 2011 to August 2012 were utilized. Binomial regression was used to estimate adjusted relative risk estimates comparing females to males. RESULTS: From December 2010 to August 2012, 8,578 contacts were made to drug users; among them 1,898 were injectors. A total of 453 injectors were eligible and referred to MAT, of which, 443 enrolled in treatment. However, regarding total outreach contacts, outreach to PWID, referral to MAT and enrollment in MAT, 8% or less of drug users accessing services were women. In contrast, weighted estimations from surveys suggest that 34% of PWIDs are female, and this approximation is similar to recent population size estimations. Overall, 43% of traditional outreach workers conducting outreach with drug users were female. Though reporting higher levels of condom usage, female PWID were more likely to report multiple sex partners, anal sex, commercial sex work and struggle under a higher burden of addiction, mental disorders and abuse. CONCLUSIONS: Services have not been mobilized adequately to address the clear needs of females who inject drugs. A clear and urgent need exists for women-centered strategies that effectively engage female PWID into HIV prevention services.

  17. Urban biowaste for solid fuel production: waste suitability assessment and experimental carbonization in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Lohri, Christian Riuji; Faraji, Adam; Ephata, Elia; Rajabu, Hassan Mtoro; Zurbrügg, Christian

    2015-02-01

    The poor state of solid waste management in Dar es Salaam (DSM), Tanzania, the large fraction of organic waste generated and a high charcoal consumption by city residents has triggered this research on carbonization of municipal biowaste. Char produced by the thermochemical conversion method of slow pyrolysis can be briquetted and used as cooking fuel alternative to wood-based charcoal. To explore the potential of biowaste carbonization in DSM, the most suitable organic wastes were selected and pyrolyzed in a simple, externally heated carbonization system developed as part of this study. A Multi-Criteria Analysis framework allowed to assess prevailing biowaste types regarding availability and accessibility, and respective suitability in terms of physical-chemical properties. The assessment, using data from a survey and lab analysis, revealed the following biowaste types with highest overall potential for char production in DSM: packaging grass/leaves (PG) used for transportation of fruit and vegetables to the markets, wood waste (WW) from wood workshops, and cardboard (CB) waste. Best practice carbonization of these biowastes in the pyrolyzer showed satisfactory char yields (PG: 38.7%; WW: 36.2%; CB: 35.7% on dry basis). Proximate composition (including volatile, fixed carbon and ash content) and heating value (PG: 20.1 MJ kg(-1); WW: 29.4 MJ kg(-1); CB: 26.7 MJ kg(-1)) of the produced char also compare well with literature data. The energy and emission-related aspects of the system still require further research and optimizations to allow financially viable and safe operation. PMID:25649406

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

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    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.

  19. 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

  20. The importance of drains for the larval development of lymphatic filariasis and malaria vectors in Dar es Salaam, United Republic of Tanzania.

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    Marcia C Castro

    Full Text Available BACKGROUND: Dar es Salaam has an extensive drain network, mostly with inadequate water flow, blocked by waste, causing flooding after rainfall. The presence of Anopheles and Culex larvae is common, which is likely to impact the transmission of lymphatic filariasis and malaria by the resulting adult mosquito populations. However, the importance of drains as larval habitats remains unknown. METHODOLOGY: Data on mosquito larval habitats routinely collected by the Urban Malaria Control Program (UMCP and a special drain survey conducted in 2006 were used to obtain a typology of habitats. Focusing on drains, logistic regression was used to evaluate potential factors impacting the presence of mosquito larvae. Spatial variation in the proportion of habitats that contained larvae was assessed through the local Moran's I indicator of spatial association. PRINCIPAL FINDINGS: More than 70% of larval habitats in Dar es Salaam were human-made. Aquatic habitats associated with agriculture had the highest proportion of Anopheles larvae presence and the second highest of Culex larvae presence. However, the majority of aquatic habitats were drains (42%, and therefore, 43% (1,364/3,149 of all culicine and 33% (320/976 of all anopheline positive habitats were drains. Compared with drains where water was flowing at normal velocity, the odds of finding Anopheles and Culex larvae were 8.8 and 6.3 (p<0.001 times larger, respectively, in drains with stagnant water. There was a positive association between vegetation and the presence of mosquito larvae (p<0.001. The proportion of habitats with mosquito larvae was spatially correlated. CONCLUSION: Restoring and maintaining drains in Dar es Salaam has the potential to eliminate more than 40% of all potential mosquito larval habitats that are currently treated with larvicides by the UMCP. The importance of human-made larval habitats for both lymphatic filariasis and malaria vectors underscores the need for a synergy between

  1. 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.

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

    Science.gov (United States)

    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

  3. 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.

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    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 < 0.05) associated with the mean log TBC. In a fixed effect model, in addition to these indicators, water shortage, water source and the refrigerator condition were significantly (p < or = 0.01) associated with log TBC. It was concluded that the milk sold in Dar es Salaam region is of poor quality and is of public health significance. PMID

  4. Trace metal pollution and its influence on the community structure of soft bottom molluscs in intertidal areas of the Dar es Salaam coast, Tanzania

    International Nuclear Information System (INIS)

    The influence of trace metal pollution on the community structure of soft bottom molluscs was investigated in intertidal areas of the Dar es Salaam coast. Significant enrichment of As, Mn, Mo, Sb, and Zn in sediments was recorded. Redundancy analysis indicated that trace metal pollution contributed 68% of the variation in community structure. Monte Carlo permutation test showed that As and Sb contributed significantly to variation in species composition. T-value biplots and van Dobben circles showed that the gastropods Acteon fortis, Assiminea ovata, and Littoraria aberrans, were negatively affected by As and Sb, while the bivalve Semele radiata and the gastropod Conus litteratus were only negatively affected by As. Bioaccumulation of As, Cd, Cu, Mo and Zn occurred in the bivalve Mactra ovalina and the gastropod Polinices mammilla. This calls for regular monitoring and management measures.

  5. HIV risk behaviors, perceived severity of drug use problems, and prior treatment experience in a sample of young heroin injectors in Dar es Salaam, Tanzania.

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    Atkinson, John; McCurdy, Sheryl; Williams, Mark; Mbwambo, Jessie; Kilonzo, Gad

    2011-01-01

    Interviews were conducted with 203 male and 95 female heroin injectors aged 17 to 25 in Dar es Salaam, Tanzania. Nearly one-quarter of participants reported injecting with needles used by someone else. Few reported cleaning needles with bleach. Multiple sexual partnerships, unprotected sex, and trading sex for money were especially present among women, the majority (55%) of whom was HIV seropositive. Self reports suggest the presence of heroin dependence among users. While most participants expressed a desire to quit their use, only 14 (5%) had been in treatment. There appears to be a large unmet need for heroin use treatment. These findings need to be considered in light of a potential forthcoming wave of heroin injection in sub-Saharan Africa. PMID:23024611

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

    Science.gov (United States)

    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

  7. 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.

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

    Science.gov (United States)

    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

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

    NARCIS (Netherlands)

    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

  10. Pulmonary tuberculosis among women with cough attending clinics for family planning and maternal and child health in Dar Es Salaam, Tanzania

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    Wandwalo Eliud R

    2009-08-01

    Full Text Available Abstract Background Tuberculosis (TB case detection in women has remained low in developing world. This study was conducted to determine the proportion of smear positive TB among women with cough regardless of the duration attending family Planning (FP and Maternal and child health (MCH clinics in Dar es Salaam. Methods We conducted a cross sectional study in all three municipal hospitals of Dar es Salaam, between October 2007 and June 2008. All women with cough attending FP and MCH clinics were screened for TB by smear microscopy. Pearson chi-square was used to compare group difference for categorical variables. Risk factors for smear positive were estimated by logistics regression with 95% confidence intervals (CI given for odds ratios indicating statistically significant relationship if the CI did not include one. Results We enrolled a total of 749 TB suspects. Five hundred and twenty nine patients (70.6% were from MCH clinics. Mean (SD age was 27.6 (5.2 years. A total of 616 (82.2% patients were coughing for less than two weeks as compared to 133 (17.8%, who coughed for two or more weeks. Among 616 TB suspects, 14 (2.3% were smear positive TB patients, and of the 133 who had coughed for two or more weeks, 13 (9.8% were smear positive TB patients. Risk factors associated with smear positive results were having attended more than one visit to any facility prior to diagnosis (OR = 6.8; 95%CI 2.57–18.0 and having HIV/AIDS (OR = 4.4; 95%CI 1.65–11.96. Long duration of cough was not a risk factor for being smear positive (OR = 1.6; 95%CI 0.59–4.49. Conclusion The proportion of smear positive TB patients among women with cough attending MCH and FP was 3.8%. Visits to any health facility prior to Diagnosis and HIV infection were risk for having a smear positive TB.

  11. 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

  12. 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

  13. 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.

  14. 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.

  15. Detection of pulmonary tuberculosis among patients with cough attending outpatient departments in Dar Es Salaam, Tanzania: does duration of cough matter?

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    Wandwalo Eliud R

    2009-07-01

    Full Text Available Abstract Background According to WHO estimates, tuberculosis case detection rate in Tanzania is less than 50% and this poses a major challenge to control tuberculosis in the country. Currently, one of the defining criteria for suspecting tuberculosis is cough for two weeks or more. We wanted to find out whether the prevalence of tuberculosis was different in patients who reported cough for two weeks or more, compared to patients with cough for less than two weeks. Methods We conducted a cross sectional study in six health facilities in Dar es Salaam, between September and October 2007. All patients aged five years and above with cough were screened for pulmonary tuberculosis (PTB by smear microscopy. Patients were divided into two groups, those who coughed for less than two weeks ( Results A total of 65,530 patients attended outpatients department (OPD. Out of these, 2274 (3.5% patients reported cough. Among patients who reported cough, 2214 (97.4% remembered their cough duration. One thousand nine hundred and seventy three patients (89.1% coughed for ≥ 2 wks as compared to 241 (10.9% patients who coughed for Conclusion Detection of smear positive PTB among patients who coughed for less than two weeks was as high as for those who coughed for two weeks or more.

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

    Science.gov (United States)

    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. PMID:26891516

  17. 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.

  18. 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.

  19. 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

  20. 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

  1. Community-owned resource persons for malaria vector control: enabling factors and challenges in an operational programme in Dar es Salaam, United Republic of Tanzania

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    Fillinger Ulrike

    2011-09-01

    Full Text Available Abstract Background Community participation in vector control and health services in general is of great interest to public health practitioners in developing countries, but remains complex and poorly understood. The Urban Malaria Control Program (UMCP in Dar es Salaam, United Republic of Tanzania, implements larval control of malaria vector mosquitoes. The UMCP delegates responsibility for routine mosquito control and surveillance to community-owned resource persons (CORPs, recruited from within local communities via the elected local government. Methods A mixed method, cross-sectional survey assessed the ability of CORPs to detect mosquito breeding sites and larvae, and investigated demographic characteristics of the CORPs, their reasons for participating in the UMCP, and their work performance. Detection coverage was estimated as the proportion of wet habitats found by the investigator which had been reported by CORP. Detection sensitivity was estimated as the proportion of wet habitats found by the CORPS which the investigator found to contain Anopheles larvae that were also reported to be occupied by the CORP. Results The CORPs themselves perceived their role as professional rather than voluntary, with participation being a de facto form of employment. Habitat detection coverage was lower among CORPs that were recruited through the program administrative staff, compared to CORPs recruited by local government officials or health committees (Odds Ratio = 0.660, 95% confidence interval = [0.438, 0.995], P = 0.047. Staff living within their areas of responsibility had > 70% higher detection sensitivity for both Anopheline (P = 0.016 and Culicine (P = 0.012: positive habitats compared to those living outside those same areas. Discussion and conclusions Improved employment conditions as well as involving the local health committees in recruiting individual program staff, communication and community engagement skills are required to optimize

  2. 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. PMID:27061958

  3. Women's preferences regarding infant or maternal antiretroviral prophylaxis for prevention of mother-to-child transmission of HIV during breastfeeding and their views on Option B+ in Dar es Salaam, Tanzania.

    Directory of Open Access Journals (Sweden)

    Matilda Ngarina

    Full Text Available BACKGROUND: The WHO 2010 guidelines for prevention of mother-to-child transmission (PMTCT of HIV recommended prophylactic antiretroviral treatment (ART either for infants (Option A or mothers (Option B during breastfeeding for pregnant women with a CD4 count of >350 cell/µL in low-income countries. In 2012, WHO proposed that all HIV-infected pregnant women should receive triple ART for life (B+ irrespective of CD4 count. Tanzania has recently switched from Option A to B+, with a few centers practicing B. However, more information on the real-life feasibility of these options is needed. This qualitative study explored women's preferences for Option A vs B and their views on Option B+ in Dar es Salaam, Tanzania. METHODS: We conducted four focus group discussions with a total of 27 pregnant women with unknown HIV status, attending reproductive and child health clinics, and 31 in-depth interviews among HIV-infected pregnant and post-delivery women, 17 of whom were also asked about B+. RESULTS: Most participants were in favor of Option B compared to A. The main reasons for choosing Option B were: HIV-associated stigma, fear of drug side-effects on infants and difficult logistics for postnatal drug adherence. Some of the women asked about B+ favored it as they agreed that they would eventually need ART for their own survival. Some were against B+ anticipating loss of motivation after protecting the child, fearing drug side-effects and not feeling ready to embark on lifelong medication. Some were undecided. CONCLUSION: Option B was preferred. Since Tanzania has recently adopted Option B+, women with CD4 counts of >350 cell/µL should be counseled about the possibility to "opt-out" from ART after cessation of breastfeeding. Drug safety and benefits, economic concerns and available resources for laboratory monitoring and evaluation should be addressed during B+ implementation to enhance long-term feasibility and effectiveness.

  4. 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

    Directory of Open Access Journals (Sweden)

    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

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

    OpenAIRE

    Black Carolyn; Kachur S Patrick; Abdulla Salim; Goodman Catherine

    2006-01-01

    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-e...

  6. Sexual behaviour, contraceptive knowledge and use among female undergraduates’ students of Muhimbili and Dar es Salaam Universities, Tanzania: a cross-sectional study

    OpenAIRE

    Somba, Magreat J; Mbonile, Milline; Obure, Joseph; Mahande, Michael J

    2014-01-01

    Background The rate of premarital sexual activity, unwanted pregnancies and illegal abortions remain higher among university students. This calls for understanding the knowledge on contraceptive use and sexual behaviours among this high risk group if the incidence of unintended pregnancy, illegal abortions and high sexual risky behaviour are to be minimized. This study aimed to assess ssexual behaviour, contraceptive knowledge and use among female undergraduates’ students of Muhimbili and Dar...

  7. La privatisation des services municipaux en Afrique de l'Est Le cas de la collecte des déchets à Nairobi et Dar es Salaam

    OpenAIRE

    Mérino, Mathieu

    2003-01-01

    No; Au cours des années quatre-vingts dix, les métropoles est-africaines ont initié un processus de privatisation d'une part croissante des services municipaux, augmentant de manière notable le rôle des entreprises privées dans la fourniture de prestations relevant initialement des autorités locales. Les services urbains les plus privilégiés sont ceux des transports en commun, des parkings, des espaces verts, des toilettes publiques ainsi que ceux du nettoyage des rues, de la collecte des déc...

  8. Homeowner's Architectural Responses to Crime in Dar Es Salaan : Its impacts and implications to urban architecture, urban design and urban management

    OpenAIRE

    Bulamile, Ludigija Boniface

    2009-01-01

    HTML clipboardThis study is about Homeowner’s architectural responses to crime in Dar es Salaam Tanzania: its impacts and implications to urban architecture, urban design and urban management. The study explores and examines the processes through which homeowners respond to crimes of burglary, home robbery and fear of it using architectural or physical elements. The processes are explored and examined using case study methodology in three cases in Dar es Salaam. The cases are residentia...

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

    OpenAIRE

    Sinha, Pammi

    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. 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 entre...

  10. 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 spatially disaggregated data from the most recent inter-census period from 2002 to 2012. This period is characterized by extensive growth in terms of area, population and car use, while the road network largely maintains status quo except for ad-hoc development in new urban areas. The paper moves...

  11. Antimicrobial Activity of Medicated Soaps Commonly Used By Dar es Salaam Residents in Tanzania.

    Science.gov (United States)

    Mwambete, K D; Lyombe, F

    2011-01-01

    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; Psoaps' 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 (Psoaps 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. PMID:22131630

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

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    Marc C. A. Wegerif

    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 seen as incapable of feeding the world’s growing and increasingly urban population. Since much of the world’s future population growth is going to happen in the cities of the developing world, ...

  14. 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

  15. Image of Nursing Profession as Viewed by Secondary School Students in Ilala District, Dar Es Salaam

    OpenAIRE

    KIWANUKA, ACHILLE

    2010-01-01

    To assess knowledge and attitudes of secondary school students in Ilala district towards the nursing profession To determine the awareness of nursing as a profession by secondary school students in Ilala district, explore factors that promote aspiration to enroll in nursing schools and to explore factors that deter aspiration to enroll in nursing schools. The study was exploratory cross sectional using both qualitative and quantitative methods and was conducted in Azania and Jangwani secondar...

  16. Determinants of Anemia in postpartum HIV-negative Women in Dar es Salaam, Tanzania.

    OpenAIRE

    Petraro, P; Duggan, C.; Urassa, W.; Msamanga, G; Makubi, A; Spiegelman, D.; Fawzi, W. W.

    2013-01-01

    The determinants of anemia during both pregnancy and postpartum recovery remain incompletely understood in sub-Saharan African women. In a prospective cohort study among pregnant women, we assessed dietary, biochemical, anthropometric, infectious and sociodemographic factors at baseline. In multivariate Cox proportional hazards models, we examined predictors of incident anemia (hemoglobin

  17. Determinants of Anemia in Postpartum HIV-Negative Women in Dar es Salaam, Tanzania

    OpenAIRE

    Petraro, Paul; Duggan, Christopher Paul; Urassa, Willy; Msamanga, Gernard; Makubi, Abel; Spiegelman, Donna Lynn; Wafaie W Fawzi

    2013-01-01

    Objective: The determinants of anemia during both pregnancy and postpartum recovery remain incompletely understood in sub-Saharan African women. Subjects/methods: In a prospective cohort study among pregnant women, we assessed dietary, biochemical, anthropometric, infectious and sociodemographic factors at baseline. In multivariate Cox proportional hazards models, we examined predictors of incident anemia (hemoglobin

  18. Vitamin A Supplementation and Other Predictors of Anemia Among Children from Dar Es Salaam, Tanzania.

    OpenAIRE

    Villamor, E; Mbise, R; Spiegelman, D.; Ndossi, G; Fawzi, W. W.

    2000-01-01

    The associations of hemoglobin, hematocrit, and packed cell volume with socioeconomic factors, malaria, human immunodeficiency virus (HIV) infection, and nutritional status were examined among 687 children admitted to hospital with pneumonia participating in a double blind, placebo-controlled trial of vitamin A supplementation. Children were randomized to receive 2 doses of vitamin A (200,000 IU) or placebo at baseline, and additional doses at 4 and 8 months after discharge from hospital. Hem...

  19. 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...

  20. 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...

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

    Directory of Open Access Journals (Sweden)

    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.

  2. 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.

  3. Risk Factors of Surgical Site Infection at Muhimbili National Hospital, Dar es Salaam, Tanzania

    OpenAIRE

    Akoko, L.O.; Mwanga, A.H.; Fredrick, F.; Mbembati, N.M.

    2012-01-01

    Surgical site infection (SSI) is a common source of morbidity among operated patients. At Muhimbili National Hospital (MNH), studies indicate that the rate of SSI has been increasing over the past thirty years. The aim of this study was to determine the prevalence and factors associated with SSI among patients undergoing surgery at MNH. This was a hospital-based cross-sectional study. One hundred and eighteen patients who underwent surgical procedures in the surgical wards were recruited. Dem...

  4. 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

  5. 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.

  6. The Prevalence of Posttraumatic Stress Disorder and Associated Mental Health Problems Among Institutionalized Orphans in Dar es salaam, Tanzania

    OpenAIRE

    Myovela, Benjamin

    2012-01-01

    Orphanhood is becoming a more common experience for children in Tanzania, in part as a consequence of the AIDS pandemic, trauma and poverty. The number of orphans and risk of psychopathology has been steadily increasing even in regions where the AIDS epidemic has stabilized. Institutional care for orphaned children is uncommon in sub-Sahara Africa and seen as a last resort primarily as orphanages are often seen as a source of unhealthy psychological development and orphans’ ability to survive...

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

    OpenAIRE

    Maisara Mhode; Tumaini Nyamhanga

    2016-01-01

    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 live...

  8. 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.

  9. Evaluation of simple rapid HIV assays and development of national rapid HIV test algorithms in Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Mbwana Judica

    2009-02-01

    Full Text Available Abstract Background Suitable algorithms based on a combination of two or more simple rapid HIV assays have been shown to have a diagnostic accuracy comparable to double enzyme-linked immunosorbent assay (ELISA or double ELISA with Western Blot strategies. The aims of this study were to evaluate the performance of five simple rapid HIV assays using whole blood samples from HIV-infected patients, pregnant women, voluntary counseling and testing attendees and blood donors, and to formulate an alternative confirmatory strategy based on rapid HIV testing algorithms suitable for use in Tanzania. Methods Five rapid HIV assays: Determine™ HIV-1/2 (Inverness Medical, SD Bioline HIV 1/2 3.0 (Standard Diagnostics Inc., First Response HIV Card 1–2.0 (PMC Medical India Pvt Ltd, HIV1/2 Stat-Pak Dipstick (Chembio Diagnostic System, Inc and Uni-Gold™ HIV-1/2 (Trinity Biotech were evaluated between June and September 2006 using 1433 whole blood samples from hospital patients, pregnant women, voluntary counseling and testing attendees and blood donors. All samples that were reactive on all or any of the five rapid assays and 10% of non-reactive samples were tested on a confirmatory Inno-Lia HIV I/II immunoblot assay (Immunogenetics. Results Three hundred and ninety samples were confirmed HIV-1 antibody positive, while 1043 were HIV negative. The sensitivity at initial testing of Determine, SD Bioline and Uni-Gold™ was 100% (95% CI; 99.1–100 while First Response and Stat-Pak had sensitivity of 99.5% (95% CI; 98.2–99.9 and 97.7% (95% CI; 95.7–98.9, respectively, which increased to 100% (95% CI; 99.1–100 on repeat testing. The initial specificity of the Uni-Gold™ assay was 100% (95% CI; 99.6–100 while specificities were 99.6% (95% CI; 99–99.9, 99.4% (95% CI; 98.8–99.7, 99.6% (95% CI; 99–99.9 and 99.8% (95% CI; 99.3–99.9 for Determine, SD Bioline, First Response and Stat-Pak assays, respectively. There was no any sample which was concordantly false positive in Uni-Gold™, Determine and SD Bioline assays. Conclusion An alternative confirmatory HIV testing strategy based on initial testing on either SD Bioline or Determine assays followed by testing of reactive samples on the Determine or SD Bioline gave 100% sensitivity (95% CI; 99.1–100 and 100% specificity (95% CI; 96–99.1 with Uni-Gold™ as tiebreaker for discordant results.

  10. 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

    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...... postabortion contraception. Follow-up information was obtained 12 months after the abortion among 59 percent of the women. Among these, 79 percent of the married women and 84 percent of the single women stated they were using contraception at 12 months. Condom use among the single women increased significantly...... HIV and condom use should be considered an essential aspect of postabortion care....

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

    Science.gov (United States)

    Mhode, Maisara; Nyamhanga, Tumaini

    2016-01-01

    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. PMID:27110395

  12. Neonatal sepsis at Muhimbili National Hospital, Dar es Salaam, Tanzania; aetiology, antimicrobial sensitivity pattern and clinical outcome

    Directory of Open Access Journals (Sweden)

    Mhada Tumaini V

    2012-10-01

    Full Text Available Abstract Background Neonatal sepsis contributes significantly to morbidity and mortality among young infants. The aetiological agents as well as their susceptibility to antimicrobial agents are dynamic. This study determined aetiology, antimicrobial susceptibility and clinical outcome of neonatal sepsis at Muhimbili National Hospital. Methods Three hundred and thirty neonates admitted at the Muhimbili National Hospital neonatal ward between October, 2009 and January, 2010 were recruited. Standardized questionnaires were used to obtain demographic and clinical information. Blood and pus samples were cultured on MacConkey, blood and chocolate agars and bacteria were identified based on characteristic morphology, gram stain appearance and standard commercially prepared biochemical tests. Antimicrobial sensitivity testing was performed for ampicillin, cloxacillin, gentamicin, amikacin, cefuroxime and ceftriaxone on Mueller Hinton agar using the Kirby Bauer diffusion method. Results Culture proven sepsis was noted in 24% (74/330 of the study participants. Isolated bacterial pathogens were predominantly Staphylococcus aureus, Klebsiella spp and Escherichia coli. Klebsiella spp 32.7% (17/52 was the predominant blood culture isolate in neonates aged below seven days while Staphylococcus aureus 54.5% (12/22 was commonest among those aged above seven days. Staphylococcus aureus was the predominant pus swabs isolate for both neonates aged 0–6 days 42.2% (98/232 and 7–28 days 52.3% (34/65. Resistance of blood culture isolates was high to ampicillin 81.1% (60/74 and cloxacillin 78.4% (58/74, moderate to ceftriaxone 14.9% (11/74 and cefuroxime 18.9% (14/74, and low to amikacin 1.3% (1/74. Isolates from swabs had high resistance to ampicillin 89.9% (267/297 and cloxacillin 85.2 (253/297, moderate resistance to ceftriaxone 38.0% (113/297 and cefuroxime 36.0% (107/297, and low resistance to amikacin 4.7% (14/297. Sepsis was higher in neonates with fever and hypothermia (p=0.02, skin pustules (p Conclusions Staphylococcus aureus was predominant isolate followed by Klebsiella and Escherichia coli. There was high resistance to ampicillin and cloxacillin. Mortality rate due to neonatal sepsis was high in our setting. Routine antimicrobial surveillance should guide the choice of antibiotics for empirical treatment of neonatal sepsis.

  13. Patient Satisfaction with Health Care Services Provided at HIV Clinics at Amana and Muhimbili Hospitals in Dar es Salaam.

    OpenAIRE

    Kagashe, G A B; Rwebangila, F

    2011-01-01

    Since the establishment of free HIV/AIDS care and treatment services in Tanzania a lot of research has been done to assess how health care providers discharge their duties in these clinics. Little research however has been done regarding satisfaction of HIV patients with free health care services provided. To determine satisfaction of HIV patients with health care services provided at the HIV clinics and specifically, to determine patients' satisfaction with the general physical environment o...

  14. “Adverse Drug Reaction Reporting” Knowledge, Attitude and Practices of Community Pharmacy Dispensers in Dar es salaam, Tanzania

    OpenAIRE

    Shimwela, Grace Mng’ong’o

    2011-01-01

    Under reporting of adverse drug reactions (ADRs) by healthcare personnel is a common problem of many Pharmacovigilence programs. Lack of involvement of healthcare professionals such as pharmacists and other pharmaceutical dispensers has been cited as one of the reasons for under reporting. Pharmaceutical dispensers in the community pharmacies are in unique position by virtue of their training and profession to observe ADRs in patients, as many patients often try to avoid doctor consultation f...

  15. 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...

  16. THE EVOLUTION OF THE LAND USE STRUCTURE OF DAR ES SALAAM 1890-1 990: A STUDY IN THE EFFECTS OF LAND POLICY, Volume 1

    OpenAIRE

    Kironde, Lusugga

    1994-01-01

    Theoretically, land policy is presented as a necessary intervention by governments in order to iron out the inefficiencies inherent in land markets. The result would be a smooth working urban land market, yielding an equitable and efficient land use structure. In practice though, land policy is part and parcel, and, indeed, a paradigm of the wiser issues of governance. Historically, land policy has been used to serve colonial interests; to achieve segregation between social groups in society;...

  17. THE EVOLUTION OF THE LAND USE STRUCTURE OF DAR ES SALAAM 1890-1 990: A STUDY IN THE EFFECTS OF LAND POLICY

    OpenAIRE

    Kironde, Lusugga

    1994-01-01

    Theoretically, land policy is presented as a necessary intervention by governments in order to iron out the inefficiencies inherent in land markets. The result would be a smooth working urban land market, yielding an equitable and efficient land use structure. In practice though, land policy is part and parcel, and, indeed, a paradigm of the wiser issues of governance. Historically, land policy has been used to serve colonial interests; to achieve segregation between social groups in society;...

  18. 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

    contraception or condoms though they were also at risk of STDs and HIV. These girls were getting pregnant expecting their boyfriends to marry them, or because they did not think they could become pregnant or failed to use contraception correctly. Most adolescent girls are not aware of the 1994 Tanzanian policy...

  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

    for socio-economic details, contraceptive knowledge/use, age at first intercourse and number of sexual partners. In the qualitative part, 51 teenage girls were interviewed in-depth about their relationships with their partners, sexual behaviour, contraceptive use and reasons for non-use, and why they became...... pregnant. The girls were sexually active at an early age and having sex mainly with men older than themselves. Although most of the girls were in love with and enjoyed sex with their partners, they also entered these relationships to obtain money or gifts in exchange for sex. Most were not using...

  20. 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

  1. Social Cognitive Determinants of HIV Voluntary Counselling and Testing Uptake among Married Individuals in Dar es Salaam Tanzania: Theory of Planned Behaviour (TPB).

    OpenAIRE

    Mtenga, Sally M.; Exavery, Amon; Kakoko, Deodatus; Geubbels, Eveline

    2015-01-01

    Background Cumulative evidence indicates increasing HIV infection among married individuals. Voluntary Counselling and Testing for HIV (HCT) is known to be an effective intervention to induce safer sex behaviour and access to early treatment, care and support among married individuals, which are important for HIV prevention. In this context, knowledge of factors associated with HCT uptake among married individuals is critical in promoting the use of the services. This study therefore intended...

  2. 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.

  3. 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

    Illegal abortion is known to be a major contributor to maternal mortality. The objective of the study was firstly to identify women with illegally induced abortion, (IA) and to compare them with women admitted with a spontaneous abortion (SA) or receiving antenatal care (AC), and secondly...

  4. 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…

  5. 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+

  6. Assessment of Implementation of International Health Regulations (2005) on Preventing Infectious Diseases: A Case Study of Julius Nyerere International Airport, Dar es Salaam.

    OpenAIRE

    Bakari, Edith

    2012-01-01

    The International Health Regulations (IHR) (2005) is a legal instrument binds all World Health Organization (WHO) Member States in order to prevent and control the Public Health Emergencies of International Concern (PHEIC). In this connection, the points of entry (POE) have been identified to be potential areas for effective interventions. In the 58th World Health Assembly (WHA) held in Geneva, Switzerland in 2005 WHO Member States agreed to strengthen the identified core capacities including...

  7. Awareness of Food Labelling and Use of the Information in Purchasing Pre Packaged Food Products Among Consumers in Ilala Municipality Dar es Salaam

    OpenAIRE

    Samson, G.

    2012-01-01

    Liberalization of trade, globalization and development in food science and technology has resulted in an increase in trade and consumption of pre-packaged foods. Reading food labelling information is important to assist in making informed choices of food. This study determined level of awareness on pre-packaged food labelling information among consumers in Ilala Municipality, their perception on the importance of such information and difficulties encountered in reading and using pre- packaged...

  8. Awareness of Rheumatic Heart Disease Prevention among Primary Health Care Providers and People Aged Nine Years and Above in Kinondoni Municipality Dar es salaam, Tanzania.

    OpenAIRE

    Maria , Manase R

    2011-01-01

    Acute Rheumatic Fever (ARF) is an autoimmune consequence of infection with Group A -haemolytic Streptococci (GAS). It causes an acute generalised inflammatory response and an illness that selectively affects the heart, joints, brain and skin. ARF leaves no lasting damage to the brain, joints or skin. However, damage to the heart valves, particularly the mitral and aortic valves, may persist after an acute episode has resolved. This involvement of the cardiac valves is known as Rheumatic Heart...

  9. Diabetic foot: prevalence, knowledge, and foot self-care practices among diabetic patients in Dar es Salaam, Tanzania – a cross-sectional study

    OpenAIRE

    Chiwanga, Faraja S.; Njelekela, Marina A

    2015-01-01

    Background At the time of diagnosis, more than 10 % of people with type 2 diabetes mellitus have one or two risk factors for a foot ulceration and a lifetime risk of 15 %. Diabetic foot ulcers can be prevented through well-coordinated foot care services. The objective of this study was to determine knowledge of foot care and reported practice of foot self-care among diabetic patients with the aim of identifying and addressing barriers to preventing amputations among diabetic patients. Methods...

  10. 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.

  11. 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.

  12. 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.

  13. Urbanisation and its discontents: urban refugees in Tanzania

    Directory of Open Access Journals (Sweden)

    Marc Sommers

    1999-04-01

    Full Text Available This article explores the different labels under which refugees in Dar es Salaam may be categorised. It identifies and profiles differentgroups of urban refugee in Dar es Salaam and considers some common assumptions about urban refugees.

  14. Victims and/or active social agents? A study of adolescent girls with induced abortion in urban Tanzania

    DEFF Research Database (Denmark)

    Silberschmidt, Margrethe

    2001-01-01

    High-risk sexual behaviour, adolescent girls, induced abortion, sugar-daddies, Dar Es Salaam, Tanzania......High-risk sexual behaviour, adolescent girls, induced abortion, sugar-daddies, Dar Es Salaam, Tanzania...

  15. Interpretation of California mastitis test scores using Staphylococcus aureus culture results for screening of subclinical mastitis in low yielding smallholder dairy cows in the Dar es Salaam region of Tanzania.

    Science.gov (United States)

    Kivaria, F M; Noordhuizen, J P T M; Nielen, M

    2007-03-17

    Screening of subclinical mastitis under field conditions is done using the California mastitis test (CMT). CMT score of > or = 1 corresponding to > or = 500,000 somatic cells ml(-1) is commonly used as threshold of subclinical mastitis in temperate countries. However, given the innately high physiological level of somatic cells in low yielding dairy cows, this threshold may not apply to low yielding dairy cows. The current study was undertaken to investigate the clinical utility of CMT for screening of Staphylococcus aureus subclinical mastitis in low yielding smallholder dairy cows in Tanzania. A total of 1151 of quarter-milk samples were CMT tested, of these 914-originated from cows with a lactation period of 14-305 days. All samples were screened for subclinical mastitis by the CMT as well as microbiological culture of single, duplicate (two consecutive) and triplicate (three consecutive) samples as a gold standard. For the duplicate and triplicate quarter-samples, cows were considered positive for S. aureus subclinical mastitis if results of microbiologic culture for S. aureus were positive for two of two, and for at least two of the first three consecutive quarter-milk samples collected from that cow, respectively. Using a CMT score of > or = 1 would classify 78.6% of the 940 quarter-samples as positive. Eighty-two percent of the samples in which S. aureus was isolated had CMT scores > or = 2; this would classify 51.6% of the 940 quarter-samples as positive. For the single sample, this cut-off had sensitivity, specificity and likelihood ratio for S. aureus of 0.87, 0.83 and 4.24, respectively. For the duplicate quarter-milk samples this cut-off had sensitivity, specificity, and likelihood ratio of 0.94, 0.86, and 5.19. While, for the triplicate quarter-milk samples this cut-off had sensitivity, specificity and likelihood ratio of 0.97, 0.92 and 7.47, respectively. Based on these results and practical considerations, it is concluded that CMT score of > or = 2 corresponding to > or = 800,000 somatic cells Ml(-1) is the best cut-off to correctly identify S. aureus intramammary infections in low yielding dairy cows in Tanzania. PMID:17137660

  16. 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

  17. Comparaison de MNTs générés à partir de données LiDAR terrestre et de photographies aériennes prises à basse altitude

    OpenAIRE

    Ouedraogo, Mohamar

    2012-01-01

    In this presentation we compare DEMs generated using terrestrial LIDAR and UAV data. The study site is a small agricultural watershed located near the region of Gembloux in Belgium. Terresttrial LiDAR data was collected using Trimble GX trought 14 scans. After correcting errors by using statistical approach, scans are meshed to generate a DEM of 1 m x 1 m resolution. UAV data was collected using the X100 UAV commercialized by gatewing. Data was processed in the open source MICMAC software to...

  18. Oral health behavior patterns among Tanzanian university students:a repeat cross-sectional survey

    OpenAIRE

    Åstrøm Anne; Masalu Joyce

    2001-01-01

    Abstract Purpose This study examines oral health behavioral trends and the development of sociodemographic differences in oral health behaviors among Tanzanian students between 1999 and 2000. Methods The population targeted was students attending the Muhimbili University College of Health Sciences (MUCHS) at the University of Dar es Salaam (UDSM), Dar es Salaam, Tanzania. Cross-sectional surveys were conducted and a total of 635 and 981 students, respectively, completed questionnaires in 1999...

  19. 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

  20. 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...

  1. 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...

  2. 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)...

  3. 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)...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. LiDAR as a Web Service

    OpenAIRE

    Balija, Damir

    2011-01-01

    LiDAR(Light Detection And Ranging) is a device, which works in a similar way as radar, but instead of radio waves, it uses light. We can use it as a mean to detect particles in the air (mainly air polution particles) or for measuring weather conditions. LiDAR with other supporting elements forms LiDAR system. In our example LiDAR system will be used remotely, in particular by remote user. Goals: a) To plan and project protocol for exchanging messages between client (user, costumer) and ...

  10. GRUČENJE PODATKOV LiDAR

    OpenAIRE

    Založnik, Boštjan

    2014-01-01

    Cilje diplomske naloge je raziskati možnosti uporabe algoritmov gručenja za obdelavo podatkov LiDAR. Prvi del diplomske naloge predstavlja podatke LiDAR in algoritme gručenja. S senzorji LiDAR, pritrjenimi na letala ali helikopterje, je omogočeno hitro in natančno modeliranje površja. Metode gručenje predstavljajo enega izmed pristopov za detekcijo objektov na površju. Gručenje je vrsta nenadzorovane klasifikacije podatkov. Za učinkovito implementacijo algoritmov gručenja so po...

  11. 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...

  12. 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...

  13. Direct Georeferencing of Stationary LiDAR

    OpenAIRE

    Ahmed Mohamed; Benjamin Wilkinson

    2009-01-01

    Unlike mobile survey systems, stationary survey systems are given very little direct georeferencing attention. Direct Georeferencing is currently being used in several mobile applications, especially in terrestrial and airborne LiDAR systems. Georeferencing of stationary terrestrial LiDAR scanning data, however, is currently performed indirectly through using control points in the scanning site. The indirect georeferencing procedure is often troublesome; the availability of control stations w...

  14. 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...

  15. Nanomedicinos teisinis reglamentavimas: ES ir JAV požiūris

    OpenAIRE

    Varvaštian, Samvel

    2013-01-01

    Magistro baigiamajame darbe yra nagrinėjamas dabartinis nanomedicinos teisinis reglamentavimas ES ir JAV. Ši tema Lietuvoje iki šiol dar nebuvo tyrinėjimų objektu. Pirmoji darbo dalis supažindina skaitytoją su nanomedicina bei su ja susijusių sąvokų problematiką. Antroji dalis atskleidžia nanomedicinos teisinio reglamentavimo prielaidas ES, o trečioji dalis – JAV. Be to, atsižvelgiant į gautus rezultatus, yra įvertinamos galimos nanomedicinos teisinio reglamentavimo perspektyvos ateityje. Dar...

  16. 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...

  17. Rigorous LiDAR Strip Adjustment with Triangulated Aerial Imagery

    OpenAIRE

    Zhang, Y. J.; Xiong, X. D.; Hu, X Y

    2013-01-01

    This paper proposes a POS aided LiDAR strip adjustment method. Firstly, aero-triangulation of the simultaneously obtained aerial images is conducted with a few photogrammetry-specific ground control points. Secondly, LiDAR intensity images are generated from the reflectance signals of laser foot points, and conjugate points are automatically matched between the LiDAR intensity image and the aero-triangulated aerial image. Control points used in LiDAR strip adjustment are derived from...

  18. Applications of LiDAR measurement for road management

    OpenAIRE

    AKIYAMA, Shinpei; TAKAGI, Masataka

    2012-01-01

    Since LiDAR (Light Detection And Ranging) is a suitable equipment for archiving three-dimensional surface data of any objects. Moreover, aerial LiDAR is used for the topographical survey, urban planning or forest measurement. On the other hand, ground based LiDAR has a potential for other purposes, such as landslide monitoring or landcover change monitoring. This paper reports method of landslide and landcover monitoring using LiDAR for road management. Firstly, landslide monitoring technique...

  19. Terrain classification using multi-wavelength LiDAR data

    OpenAIRE

    Thomas, Judson J. C.

    2015-01-01

    Approved for public release; distribution is unlimited With the arrival of Optech’s Titan multispectral LiDAR sensor, it is now possible to simultaneously collect three different wavelengths of LiDAR data. Much of the work performed on multispectral LiDAR data involves gridding the point cloud to create Digital Elevation Models and multispectral image cubes. Gridding and raster analysis can have negative implications with respect to LiDAR data integrity and resolution. Presented here is a ...

  20. 2012 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Hoh 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 Hoh River watershed survey area for the Puget Sound LiDAR Consortium and...

  1. 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...

  2. 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)...

  3. 2014 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Cedar River Watershed (Delivery 2)

    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)...

  4. 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

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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,...

  12. 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...

  13. 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...

  14. 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...

  15. Modelización del monte bajo de castaño de Brañalonga (Tineo) mediante tecnología LiDAR

    OpenAIRE

    Arias Fernández, Marina

    2015-01-01

    El propósito del presente estudio de investigación es el desarrollo de modelos de predicción de variables dasométricas a partir de datos LiDAR del PNOA para el monte bajo de Castanea sativa, comparando los datos generados mediante tecnología LiDAR con los del inventario forestal tradicional. Se realizó el tratamiento previo de los datos LiDAR para la obtención de los estadísticos de las variables LiDAR. Se llevó a cabo un inventario forestal, en el cual se midió, entre otros parámetros, el di...

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

    Directory of Open Access Journals (Sweden)

    José Antonio Segarra

    2011-01-01

    Full Text Available 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 valores, el modelo de negocio y las tareas de dirección de la empresa.

  17. 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.

  18. "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…

  19. 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…

  20. Physician Li Bo

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Li Bo,32,an attending physician at Xiyuan Hospital of the China Academy of Chinese Medical Sciences,spent a year and a half between 2008 and 2010 participating in a traditional Chinese medicine (TCM) project at the Muhimbili National Hospital in Dar Es Salaam,Tanzania.Now back in Beijing,he spoke to ChinAfrica

  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. 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

  3. 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

  4. 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.

  5. 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....

  6. 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.

  7. 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…

  8. 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 ...

  9. 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

  10. 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...

  11. LiDAR Utility for Natural Resource Managers

    OpenAIRE

    Alistair Matthew Stuart Smith; Andrew Thomas Hudak; Jeffrey Scott Evans

    2009-01-01

    Applications of LiDAR remote sensing are exploding, while moving from the research to the operational realm. Increasingly, natural resource managers are recognizing the tremendous utility of LiDAR-derived information to make improved decisions. This review provides a cross-section of studies, many recent, that demonstrate the relevance of LiDAR across a suite of terrestrial natural resource disciplines including forestry, fire and fuels, ecology, wildlife, geology, geomorphology, and surface ...

  12. Storage, manipulation, and visualization of LiDAR data

    OpenAIRE

    Schön, Bianca; Bertolotto, Michela; Laefer, Debra F.; Morrish, Sean

    2009-01-01

    In recent years, three-dimensional (3D) data has become increasingly available, in part as a result of significant technological progresses in Light Detection and Ranging (LiDAR). LiDAR provides longitude and latitude information delivered in conjunction with a GPS device, and elevation information generated by a pulse or phase laser scanner, which together provide an effective way of acquiring accurate 3D information of a terrestrial or manmade feature. The main advantages of LiDAR over conv...

  13. ISKANJE NEPOKRITIH DELOV TERENA V PODATKIH LiDAR

    OpenAIRE

    Osojnik, Monika

    2013-01-01

    LiDAR je sodobna tehnologija daljinskega zaznavanja, ki s pomočjo laserske svetlobe omogoča hitro in natančno zajemanje podatkov o zemeljskem površju in objektih na njem. Zaradi slabe odbojnosti svetlobe na vodnih področjih in zaradi ovir, ki zakrivajo okolico, sistemi LiDAR pogosto ne zajamejo celovite slike površja. Zaradi kasnejših prostorskih analiz, temelječih na podatkih LiDAR, je smiselno takšne dele v podatkih LiDAR pravočasno odkriti in odpraviti. V tem diplomskem delu predstavlja...

  14. A Comparison of LiDAR and Radiosonde Wind Measurements

    OpenAIRE

    Kumer, Valerie-Marie; Reuder, Joachim; Furevik, Birgitte Rugaard

    2014-01-01

    Doppler LiDAR measurements are already well established in the wind energy research and their accuracy has been tested against met mast data up to 100 m above ground. However, the new generation of scanning LiDAR have a much higher range and thus it is not possible to verify measurements at higher altitudes. Therefore, the LiDAR Measurement Campaign Sola (LIMECS) was conducted at the airport of Stavanger from March to August 2013 to compare LiDAR and radiosonde winds. It was a collab...

  15. 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

  16. "Unsicher ist es anderswo!" : Räumliche Sicherheitswahrnehmung in Konstanz

    OpenAIRE

    Brandt, Hannes; Hillmann, Hans Christian; Meinecke, Johannes

    2011-01-01

    Das Projekt "Unsicher ist es Anderswo" widmet sich der Stadt Konstanz zunächst als Ganzes. Ziel war, die subjektiven Räume von Unsicherheit/Gefahr aus der Sicht der BürgerInnen mit der "objektiven" Kriminalstatistik und den Erfahrungen der Polizei zu vergleichen.Dazu wurden Experteninterviews mit der Polizei Konstanz und den Nachtwanderern (Bürgerinitiative), geführt und 38 AnwohnerInnen in Leitfadeninterviews zu deren subjektiven Wahrnehmung der räumlichen Sicherheit in Konstanz befragt. Dar...

  17. Diseño e implementación de componentes software para dar soporte a la plataforma MEWiN en el sistema operativo Contiki

    OpenAIRE

    Navarro Hellín, Honorio

    2011-01-01

    El presente proyecto final de carrera que tiene como título: "Diseño e Implementación de componentes software para dar soporte a la plataforma MEWiN en el sistema operativo Contiki" pretende dar soporte software al dispositivo MEWiN desarrollado. En la actualidad el sistema operativo Contiki es uno de los más utilizados en el ámbito de las redes inalámbricas de sensores, dada su característica de código libre y su alta escalabilidad. La mayoría de fabricantes de dispositivos electrónicos u...

  18. 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...

  19. 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...

  20. 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".

  1. Lava flow texture LiDAR signatures

    Science.gov (United States)

    Whelley, P.; Garry, W. B.; Scheidt, S. P.; Irwin, R. P., III; Fox, J.; Bleacher, J. E.; Hamilton, C. W.

    2014-12-01

    High-resolution point clouds and digital elevation models (DEMs) are used to investigate lava textures on the Big Island of Hawaii. An experienced geologist can distinguish fresh or degraded lava textures (e.g., blocky, a'a and pahoehoe) visually in the field. Lava texture depends significantly on eruption conditions, and it is therefore instructive, if accurately determined. In places where field investigations are prohibitive (e.g., Mercury, Venus, the Moon, Mars, Io and remote regions on Earth) lava texture must be assessed from remote sensing data. A reliable method for differentiating lava textures in remote sensing data remains elusive. We present preliminary results comparing properties of lava textures observed in airborne and terrestrial Light Detection and Ranging (LiDAR) data. Airborne data, in this study, were collected in 2011 by Airborne 1 Corporation and have a ~1m point spacing. The authors collected the terrestrial data during a May 2014 field season. The terrestrial scans have a heterogeneous point density. Points close to the scanner are 1 mm apart while 200 m in the distance points are 10 cm apart. Both platforms offer advantages and disadvantages beyond the differences in scale. Terrestrial scans are a quantitative representation of what a geologist sees "on the ground". Airborne scans are a point of view routinely imaged by other remote sensing tools, and can therefore be quickly compared to complimentary data sets (e.g., spectral scans or image data). Preliminary results indicate that LiDAR-derived surface roughness, from both platforms, is useful for differentiating lava textures, but at different spatial scales. As all lava types are quite rough, it is not simply roughness that is the most advantageous parameter; rather patterns in surface roughness can be used to differentiate lava surfaces of varied textures. This work will lead to faster and more reliable volcanic mapping efforts for planetary exploration as well as terrestrial

  2. COSIMA-ES-PORT

    DEFF Research Database (Denmark)

    Barfod, Michael Bruhn; Leleur, Steen

    2007-01-01

    -ES-PORT model showed some promising perspectives in the handling of the three pre-feasibility studies. Parameters such as cargo handling and ship related issues could with advantage be implemented in the decision model and forecasted similarly to road infrastructure impacts. Furthermore, the development......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...... 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...

  3. La educación inclusiva es nuestra tarea

    Directory of Open Access Journals (Sweden)

    Meybol Calderón

    2012-06-01

    Full Text Available La educación inclusiva es un tema que se ha venido trabajando desde hace relativamente pocos años en el Perú, pero en otros países se viene realizando desde hace muchos años. Por ello esta investigación busca dar a conocer todos aquellos elementos que son necesarios para lograr una inclusión adecuada de los niños, tomando como centro al niño, reconociéndolo como un ser humano integral que no solo aprende conceptos, sino también aprende a convivir e interactuar con su medio. Es aquí donde debemos tomar en cuenta el respeto a la diversidad que se debe dar en el aula, ya que al convivir se comparten experiencias con personas diferentes, como pueden ser los niños con necesidades especiales o simplemente con las de un niño regular. En esta investigación hemos querido resaltar la importancia de los roles de los agentes educativos para el buen desarrollo de la inclusión de los niños, siendo estos indispensables para lograrlo.

  4. 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.

  5. UAS TOPOGRAPHIC MAPPING WITH VELODYNE LiDAR SENSOR

    OpenAIRE

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

    2016-01-01

    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 sensor...

  6. 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.

  7. 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...

  8. TENSOR MODELING BASED FOR AIRBORNE LiDAR DATA CLASSIFICATION

    OpenAIRE

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

    2016-01-01

    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 kee...

  9. 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.

  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. 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...

  12. 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...

  13. Extraction of Rooftops from LiDAR and Multispectral Imagery

    OpenAIRE

    Kim, Angela M.; Fred A. Kruse; Olsen, Richard C.; Clasen, Chris C.

    2012-01-01

    Imaging and Applied Optics Technical Digest, 2012 A rooftop extraction scheme based on statistical analysis of the LiDAR point cloud is presented. Spectral data are incorporated to reduce false alarms due to vegetation and to provide spectral discrimination of rooftop materials. This research was partially supported by the Science and Technology Directorate, USA Department of Homeland Security (DHS). The LiDAR data were provided by the Association of Monterey Bay Area Governments (AM...

  14. Enhancing 3D LiDAR Data Handling

    OpenAIRE

    Laefer, Debra; Bertolotto, Michela; Schoen-Phelan, Bianca

    2010-01-01

    more evident than in the limited capabilities of Spatial Information Systems (SIS) to manipulate data from aerial Light Detection and Ranging (LiDAR). Currently, multiple software packages are needed to conduct three-dimensional (3D) analysis of LiDAR data. This workflow heavily relies on importing and exporting different file formats, thus potentially losing accuracy and increasing costs. Ideally, all required functionality would be available within a single system. New functionalities in Or...

  15. 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.

  16. Performance evaluation of lightweight LiDAR for UAV applications

    OpenAIRE

    Esposito, S.; M Mura; Fallavollita, P; Balsi, M.; Chirici, G.; A. Oradini; M. Marchetti

    2014-01-01

    In this work a new lightweight LiDAR solution designed for UAV application will be investigated. In particular, we show that using this multi-echo LiDAR it is possible to obtain DTM reconstruction of the densely forested area surveyed in good agreement with the local technical regional map (CTR). We have also estimated the mean height of the trees from the estimated CHM with relative error equal to 5%.

  17. Alternative Methodologies for LiDAR System Calibration

    OpenAIRE

    Jacky Chow; Ana Paula Kersting; Ki In Bang; Ayman Habib

    2010-01-01

    Over the last few years, LiDAR has become a popular technology for the direct acquisition of topographic information. In spite of the increasing utilization of this technology in several applications, its accuracy potential has not been fully explored. Most of current LiDAR calibration techniques are based on empirical and proprietary procedures that demand the system’s raw measurements, which may not be always available to the end-user. As a result, we can still observe systematic discrepanc...

  18. Terrestrial LiDAR in Urban Data Acquisition

    OpenAIRE

    J. Boehm

    2009-01-01

    Terrestrial LiDAR plays an essential role in the acquisition of complete three-dimensional data for urban modeling. Especially the growing demand for detailed façade models drives the developments in acquisition and processing of terrestrial data. This paper reviews the past efforts in terrestrial data acquisition, which were mainly image based methods and gives a overview of the current state-of-the-art methods involving LiDAR data. Processing methods range from instantaneous visualization t...

  19. Adolescents' Communication with Parents, Other Adult Family Members and Teachers on Sexuality: Effects of School-Based Interventions in South Africa and Tanzania.

    Science.gov (United States)

    Namisi, Francis; Aarø, Leif Edvard; Kaaya, Sylvia; Kajula, Lusajo J; Kilonzo, Gad P; Onya, Hans; Wubs, Annegreet; Mathews, Catherine

    2015-12-01

    Cluster-randomized controlled trials were carried out to examine effects on sexual practices of school-based interventions among adolescents in three sites in sub-Saharan Africa. In this publication, effects on communication about sexuality with significant adults (including parents) and such communication as a mediator of other outcomes were examined. Belonging to the intervention group was significantly associated with fewer reported sexual debuts in Dar es Salaam only (OR 0.648). Effects on communication with adults about sexuality issues were stronger for Dar es Salaam than for the other sites. In Dar, increase in communication with adults proved to partially mediate associations between intervention and a number of social cognition outcomes. The hypothesized mediational effect of communication on sexual debut was not confirmed. Promoting intergenerational communication on sexuality issues is associated with several positive outcomes and therefore important. Future research should search for mediating factors influencing behavior beyond those examined in the present study. PMID:25724974

  20. 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.

  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. 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,...

  3. 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,...

  4. 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,...

  5. 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...

  6. Mediciones Dendrométricas y Dasométricas mediante Técnicas LiDAR y Fotogramáticas

    OpenAIRE

    Uzquiano Pérez, Sara

    2014-01-01

    Cada vez más es necesario obtener mayor información de los bosques con mayor fiabilidad la reconstrucción en 3D mediante técnicas LiDAR terrestre y fotografías aéreas a través de RPAS son nuevas tecnologías que podrían aportar este requerimiento. [...

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. Integrating LiDAR Data into Earth Science Education

    Science.gov (United States)

    Robinson, S. E.; Arrowsmith, R.; de Groot, R. M.; Crosby, C. J.; Whitesides, A. S.; Colunga, J.

    2010-12-01

    The use of high-resolution topography derived from Light Detection and Ranging (LiDAR) in the study of active tectonics is widespread and has become an indispensable tool to better understand earthquake hazards. For this reason and the spectacular representation of the phenomena the data provide, it is appropriate to integrate these data into the Earth science education curriculum. A collaboration between Arizona State University, the OpenTopography Facility, and the Southern California Earthquake Center are developing, three earth science education products to inform students and other audiences about LiDAR and its application to active tectonics research. First, a 10-minute introductory video titled LiDAR: Illuminating Earthquakes was produced and is freely available online through the OpenTopography portal and SCEC. The second product is an update and enhancement of the Wallace Creek Interpretive Trail website (www.scec.org/wallacecreek). LiDAR topography data products have been added along with the development of a virtual tour of the offset channels at Wallace Creek using the B4 LiDAR data within the Google Earth environment. The virtual tour to Wallace Creek is designed as a lab activity for introductory undergraduate geology courses to increase understanding of earthquake hazards through exploration of the dramatic offset created by the San Andreas Fault (SAF) at Wallace Creek and Global Positioning System-derived displacements spanning the SAF at Wallace Creek . This activity is currently being tested in courses at Arizona State University. The goal of the assessment is to measure student understanding of plate tectonics and earthquakes after completing the activity. Including high-resolution topography LiDAR data into the earth science education curriculum promotes understanding of plate tectonics, faults, and other topics related to earthquake hazards.

  14. INTERAKTIVNO ORODJE ZA OBDELAVO PODATKOV LiDAR

    OpenAIRE

    Pečnik, Sašo

    2010-01-01

    V tem diplomskem delu predstavljamo interaktivno orodje, ki omogoča učinkovito obdelavo in analizo podatkov, zbranih s pomočjo tehnologije LiDAR. Tehnologija LiDAR omogoča hiter zajem geometrijskih podatkov na velikem geografskem območju z visoko natančnostjo in ločljivostjo. Obseg tako zajetega nabora podatkov hitro preraste zmožnosti sodobnih računalniških sistemov in zahteva vpeljavo optimizacijskih algoritmov skozi celoten postopek njihove vizualizacije, obdelave in analize. V ta namen pr...

  15. 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...

  16. 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...

  17. 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...

  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. Performance Assessment of High Resolution Airborne Full Waveform LiDAR for Shallow River Bathymetry

    OpenAIRE

    Zhigang Pan; Craig Glennie; Preston Hartzell; Juan Carlos Fernandez-Diaz; Carl Legleiter; Brandon Overstreet

    2015-01-01

    We evaluate the performance of full waveform LiDAR decomposition algorithms with a high-resolution single band airborne LiDAR bathymetry system in shallow rivers. A continuous wavelet transformation (CWT) is proposed and applied in two fluvial environments, and the results are compared to existing echo retrieval methods. LiDAR water depths are also compared to independent field measurements. In both clear and turbid water, the CWT algorithm outperforms the other methods if only green LiDAR ob...

  20. 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

  1. 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...

  2. 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 Li...

  3. 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...

  4. 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.

  5. 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,...

  6. 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...

  7. 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...

  8. 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.

  9. Intrauterine growth of live-born Tanzanian infants.

    Science.gov (United States)

    Boersma, E R; Mbise, R L

    1979-03-01

    The incidence of low birthweight infants, the effect of intrauterine growth retardation on anthropometric measurements, and local standards of intrauterine growth curves for weight, crown-heel length and head circumference together with curves of body measurement ratios of weight/length, weight/head circumference and weight/length x head circumference are presented for the population of Dar es Salaam (Tanzania). Acomparison is made with a standard composed for a Caucasian community with completely different socio-economic and nutritional status. From 28 to 34 weeks of gestation weight gain in Dar es Salaam foetuses was reduced, while length and head circumference were relatively less affected. However, an increased intrauterine growth velocity was recorded from 34 to 38 weeks of gestation. PMID:483374

  10. Planning the unplanned

    DEFF Research Database (Denmark)

    Halloran, Afton Marian Szasz; Magid, Jakob

    2013-01-01

    Despite significant contributions to human health, livelihoods and food security, urban agriculture in Dar es Salaam has received relatively little political support from central and local government due to its informal state. As a result, many urban farmers' experience insecurity of land access ...... cultivate open spaces within the city. Nonetheless, urban agriculture will continue to persist, adapting and innovating under the pressures of urbanization. © 2013 International Institute for Environment and Development (IIED).......Despite significant contributions to human health, livelihoods and food security, urban agriculture in Dar es Salaam has received relatively little political support from central and local government due to its informal state. As a result, many urban farmers' experience insecurity of land access...

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    -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......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...... of forest utilisation under PFM, using estimates of forest condition and extraction rates based on forest inventories and 480 household surveys from 12 forests; seven under Community Based Forest Management (CBFM), three under Joint Forest Management (JFM) and two under government management (non...

  12. 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...

  13. 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.

  14. 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...

  15. Anti-Mycobacterial and Toxicity Activities of Some Priority Medicinal Plants from Lake Victoria Basin, Tanzania

    OpenAIRE

    Magadula Joseph J.; Otieno Joseph N.; Nondo Ramadhani S.; Kirimuhuzya Claude; Kadukuli E.; Orodho John A.; Okemo Paul

    2012-01-01

    Aims: This study has evaluated ethanol extracts from five medicinal plants selected through ethnobotanical study from Lake Victoria basin, Tanzania for their in vitro antimycobacterial activity against two Mycobacterium species and cytotoxicity against brine shrimp larvae. Study Design: Laboratory experimental tests. Place and Duration of Study: Institute of Traditional Medicine, Muhimbili University of Health and Allied Sciences, P.O. Box 65001, Dar es Salaam, Tanzania, bet...

  16. Application of Behavior Management Techniques for Paediatric Dental Patients by Tanzanian Dental Practitioners

    OpenAIRE

    Kawia, Hassan Mohamed; Mbawalla, Hawa Shariff; Kahabuka, Febronia Kokulengya

    2015-01-01

    Background: Management of children’s behavior is an integral component of pediatric dental practice. Objective: To investigate the oral health care providers’ awareness, use and factors for choice of behavior management techniques when attending paediatric dental patients. Methods: A cross-sectional study among dental practitioners in Dar es Salaam, Tanzania. Data collection was done through interview using a structured questionnaire. The recorded information included: awareness and applicati...

  17. Infections associated with severe malnutrition among hospitalised children in East Africa

    OpenAIRE

    Sunguya, BF; Koola, JI; Atkinson, S

    2006-01-01

    Severe protein-energy malnutrition (PEM) predisposes affected children to various infections, which either worsens their nutritional status or causes malnutrition, hence complicating their management and outcome. This study was carried out to determine the infections associated with severe malnutrition among children admitted at Kilifi District Hospital (KDH) in Kenya and Muhimbili National Hospital (MNH) in Dar es Salaam, Tanzania. Data was collected from hospital register books and online s...

  18. Bright Prospect of East Africa——A Chinese Local Government Delegation Visits Uganda and Tanzania

    Institute of Scientific and Technical Information of China (English)

    Zhang; Jigang; Li; Yanwen; Zhang; Peng

    2014-01-01

    <正>A Chinese Local Government Delegation headed by Xia Geng,Deputy Governor of Shandong Province,was sent by the CPAFFC to attend the China-East African Community Local Governors and Mayors Dialogue in Kampala,Uganda and the ChinaTanzania Local Governors and Mayors Dialogue in Dar es Salaam,Tanzania.It consisted of more than 80 members from six cities of four provinces—Shandong,Liaoning,Shaanxi and Ji-

  19. A Comparative Study on Cigarette Smoking Control Strategies Used In Tanzania and the United Kingdom

    OpenAIRE

    Hussein, Hassan

    2006-01-01

    To identify and compare different smoking control strategies used in the United Kingdom and United Republic of Tanzania Descriptive cross-sectional study Data was collected by an interview and observation at various institutions and clinics in Dar Es Salaam, Tanzania and London, UK and analysed using Epi-Info 2002. It was found that both the two countries have very good strategies against cigarette smoking but UK has a better organized system which is more effective in lowering down smoking p...

  20. 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

  1. 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

  2. Assessment of potential ICT-related collaboration and innovation capacity in east Africa

    OpenAIRE

    Cunningham, P.; Cunningham, M.; Ekenberg, L.

    2015-01-01

    Due to a significant investment in digital infrastructure and a pro-innovation policy and regulatory framework, the Innovation Ecosystems in Nairobi, Dar es Salaam and Kampala have considerably expanded over the last five years, incorporating new national and international Innovation Stakeholders. This is important in the context of realising the objectives of National Development Plans, and addressing high levels of youth and graduate unemployment. This paper presents a sub-set of results fr...

  3. Self-care, foot problems and health in Tanzanian diabetic patients and comparisons with matched Swedish diabetic patients

    OpenAIRE

    Smide, Bibbi

    2000-01-01

    The overall aim was to study self-care, foot problems and self-perceived health in 150 consecutively invited Tanzanian diabetic patients and to compare them with gender- and age-matched Swedish diabetic patients (n=150) from a middle Sweden area. The main study was cross-sectional and took place at a diabetes clinic in Dar es Salaam. All patients answered questions about their self-care satisfaction, diabetes knowledge and skills, and educational needs. Foot examination also included question...

  4. Can Mobile-Enabled Payment Methods Reduce Petty Corruption in Urban Water Provision?

    OpenAIRE

    Aaron Krolikowski

    2014-01-01

    Corruption in the urban water sector constrains economic growth and human development in low-income countries. This paper empirically evaluates the ability of novel mobile-enabled payment methods to reduce information asymmetries and mitigate petty corruption in the urban water sector’s billing and payment processes. Overcoming these barriers may promote improved governance and water service delivery. The case of Dar es Salaam is used to explore the role of mobile-enabled payment instruments ...

  5. 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.

  6. ¿Cuál es el sentido de la historia?

    Directory of Open Access Journals (Sweden)

    Javier Aldama Pinedo

    2011-05-01

    Full Text Available En este texto se hace un repaso de la constitución de la historia y la historiografía y del planteamiento de algunos filósofos (de Voltaire a Fukuyama sobre este proceso constitutivo. El hilo conductor que sigue el texto pretende dar respuesta a la pregunta: ¿cuál es el sentido de la historia?Hacia el final, el autor ensaya una respuesta a la pregunta planteada desde la perspectiva de los países periféricos. Palabras claves: Historia, historiografía, fin de la historia, Occidente.

  7. ¿Cuál es el sentido de la historia?

    OpenAIRE

    Javier Aldama Pinedo

    2011-01-01

    En este texto se hace un repaso de la constitución de la historia y la historiografía y del planteamiento de algunos filósofos (de Voltaire a Fukuyama) sobre este proceso constitutivo. El hilo conductor que sigue el texto pretende dar respuesta a la pregunta: ¿cuál es el sentido de la historia?Hacia el final, el autor ensaya una respuesta a la pregunta planteada desde la perspectiva de los países periféricos. Palabras claves: Historia, his...

  8. Volume component analysis for classification of LiDAR data

    Science.gov (United States)

    Varney, Nina M.; Asari, Vijayan K.

    2015-03-01

    One of the most difficult challenges of working with LiDAR data is the large amount of data points that are produced. Analysing these large data sets is an extremely time consuming process. For this reason, automatic perception of LiDAR scenes is a growing area of research. Currently, most LiDAR feature extraction relies on geometrical features specific to the point cloud of interest. These geometrical features are scene-specific, and often rely on the scale and orientation of the object for classification. This paper proposes a robust method for reduced dimensionality feature extraction of 3D objects using a volume component analysis (VCA) approach.1 This VCA approach is based on principal component analysis (PCA). PCA is a method of reduced feature extraction that computes a covariance matrix from the original input vector. The eigenvectors corresponding to the largest eigenvalues of the covariance matrix are used to describe an image. Block-based PCA is an adapted method for feature extraction in facial images because PCA, when performed in local areas of the image, can extract more significant features than can be extracted when the entire image is considered. The image space is split into several of these blocks, and PCA is computed individually for each block. This VCA proposes that a LiDAR point cloud can be represented as a series of voxels whose values correspond to the point density within that relative location. From this voxelized space, block-based PCA is used to analyze sections of the space where the sections, when combined, will represent features of the entire 3-D object. These features are then used as the input to a support vector machine which is trained to identify four classes of objects, vegetation, vehicles, buildings and barriers with an overall accuracy of 93.8%

  9. 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.

  10. Increasing the Efficiency of LiDAR Based Forest Inventories: A Novel Approach for Integrating Variable Radius Inventory Plots with LiDAR Data.

    Science.gov (United States)

    Falkowski, M. J.; Fekety, P.; Silva, C. A.; Hudak, A. T.

    2015-12-01

    LiDAR data are increasingly applied to support forest inventory and assessment across a variety of spatial scales. Typically this is achieved by integrating LiDAR data with forest inventory collected at fixed radius forest inventory plots. A well-designed forest inventory, one that covers the full range of structural and compositional variation across the forest of interest, is costly especially when collecting fixed radius plot data. Variable radius plots offer an alternative inventory protocol that is more efficient in terms of both time and money. However, integrating variable radius plot data with LiDAR data is problematic because the plots have unknown sizes that vary with variation in tree size. This leads to a spatial mismatch between LiDAR metrics (e.g., mean height, canopy cover, density, etc.) and plot data, which ultimately translates into errors in LiDAR derived forest inventory predictions. We propose and evaluate and novel approach for integrating variable radius plot data into a LiDAR based forest inventories in two different forest systems, one in the inland northwest and another in the northern lakes states of the USA. The novel approach calculates LiDAR metrics by weighting the point cloud proportional to return height, mimicking the way in which variable radius plot data weights tree measurements by tree size. This could increase inventory sampling efficiency, allowing for the collection of a greater number of inventory plots, and ultimately improve the performance of LiDAR based inventories.

  11. Los manatíes

    OpenAIRE

    2000-01-01

    Los manatíes pueden vivir en ríos de aguas tranquilas, canales, en bahías de agua salada y en el océano. El manatí de las Indias Occidentales, llamado científicamente Trichechus manatus, habita en la cuenca del Caribe, desde la Florida hasta Brasil.

  12. Colombia es una cosa penetrable

    Directory of Open Access Journals (Sweden)

    Gilberto Loaiza Cano

    2014-03-01

    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. NASA Goddard’s LiDAR, Hyperspectral and Thermal (G-LiHT) Airborne Imager

    OpenAIRE

    Vuong Ly; Montesano, Paul M.; Kenneth J. Ranson; Jeffrey G. Masek; Joel T. McCorkel; Douglas C. Morton; Elizabeth M. Middleton; Ross F. Nelson; Lawrence A. Corp; Cook, Bruce D

    2013-01-01

    The combination of LiDAR and optical remotely sensed data provides unique information about ecosystem structure and function. Here, we describe the development, validation and application of a new airborne system that integrates commercial off the shelf LiDAR hyperspectral and thermal components in a compact, lightweight and portable system. Goddard’s LiDAR, Hyperspectral and Thermal (G-LiHT) airborne imager is a unique system that permits simultaneous measurements of vegetation structure, fo...

  14. 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....

  15. Segmenting tree crowns from terrestrial and mobile LiDAR data by exploring ecological theories

    Science.gov (United States)

    Tao, Shengli; Wu, Fangfang; Guo, Qinghua; Wang, Yongcai; Li, Wenkai; Xue, Baolin; Hu, Xueyang; Li, Peng; Tian, Di; Li, Chao; Yao, Hui; Li, Yumei; Xu, Guangcai; Fang, Jingyun

    2015-12-01

    The rapid development of light detection and ranging (LiDAR) techniques is advancing ecological and forest research. During the last decade, numerous single tree segmentation techniques have been developed using airborne LiDAR data. However, accurate crown segmentation using terrestrial or mobile LiDAR data, which is an essential prerequisite for extracting branch level forest characteristics, is still challenging mainly because of the difficulties posed by tree crown intersection and irregular crown shape. In the current work, we developed a comparative shortest-path algorithm (CSP) for segmenting tree crowns scanned using terrestrial (T)-LiDAR and mobile LiDAR. The algorithm consists of two steps, namely trunk detection and subsequent crown segmentation, with the latter inspired by the well-proved metabolic ecology theory and the ecological fact that vascular plants tend to minimize the transferring distance to the root. We tested the algorithm on mobile-LiDAR-scanned roadside trees and T-LiDAR-scanned broadleaved and coniferous forests in China. Point-level quantitative assessments of the segmentation results showed that for mobile-LiDAR-scanned roadside trees, all the points were classified to their corresponding trees correctly, and for T-LiDAR-scanned broadleaved and coniferous forests, kappa coefficients ranging from 0.83 to 0.93 were obtained. We believe that our algorithm will make a contribution to solving the problem of crown segmentation in T-LiDAR scanned-forests, and might be of interest to researchers in LiDAR data processing and to forest ecologists. In addition, our research highlights the advantages of using ecological theories as guidelines for processing LiDAR data.

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

    OpenAIRE

    G. Mandlburger; C. Hauer; B. Höfle; H. Habersack; Pfeifer, N

    2009-01-01

    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 poin...

  17. Synergy Between LiDAR and Image Data in Context of Building Extraction

    OpenAIRE

    Poz, A. P.

    2014-01-01

    This paper compares the paradigms of LiDAR and aerophotogrammetry in the context of building extraction and briefly discusses a photogrammetric strategy for refining building roof polyhedrons previously extracted from LiDAR data. In general, empirical and theoretical studies have confirmed that LiDAR-based methodologies are more suitable in extracting planar roof faces and ridges of the roof, whereas the aerophotogrammetry are more suitable in extracting building roof outlines. In or...

  18. Portable and Airborne Small Footprint LiDAR: Forest Canopy Structure Estimation of Fire Managed Plots

    OpenAIRE

    Claudia M.C.S. Listopad; Drake, Jason B.; Weishampel, John F.; Ron. E. Masters

    2011-01-01

    This study used an affordable ground-based portable LiDAR system to provide an understanding of the structural differences between old-growth and secondary-growth Southeastern pine. It provided insight into the strengths and weaknesses in the structural determination of portable systems in contrast to airborne LiDAR systems. Portable LiDAR height profiles and derived metrics and indices (e.g., canopy cover, canopy height) were compared among plots with different fire frequency and fire season...

  19. Surface-Based Registration of Airborne and Terrestrial Mobile LiDAR Point Clouds

    OpenAIRE

    Tee-Ann Teo; Shih-Han Huang

    2014-01-01

    Light Detection and Ranging (LiDAR) is an active sensor that can effectively acquire a large number of three-dimensional (3-D) points. LiDAR systems can be equipped on different platforms for different applications, but to integrate the data, point cloud registration is needed to improve geometric consistency. The registration of airborne and terrestrial mobile LiDAR is a challenging task because the point densities and scanning directions differ. We proposed a scheme for the registration of ...

  20. Extraction of Mangrove Biophysical Parameters Using Airborne LiDAR

    OpenAIRE

    Poonsak Miphokasap; Phisan Santitamnont; Kiyoshi Honda; Wasinee Wannasiri; Masahiko Nagai

    2013-01-01

    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 scal...

  1. Point density effects on digital elevation models generated from LiDAR data

    OpenAIRE

    Duldulao, Richard L.

    2009-01-01

    Approved for public release, distribution unlimited The use of Airborne LiDAR Systems (ALS) to obtain topographical information of the earth's surface and generate Digital Elevation Models (DEMs) has grown extensively in the field of Remote Sensing. Selected areas of point cloud LiDAR data collected from Honduras in 2008 was used to produce DEMs with varying densities to show the effects of lower resolution LiDAR data. An IDL code was utilized to reduce the selected LiDAR point cloud da...

  2. CLASSIFICATION OF LiDAR DATA WITH POINT BASED CLASSIFICATION METHODS

    OpenAIRE

    N. Yastikli; Cetin, Z.

    2016-01-01

    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. applicati...

  3. Synergy Between LiDAR and Image Data in Context of Building Extraction

    Science.gov (United States)

    Dal Poz, A. P.

    2014-11-01

    This paper compares the paradigms of LiDAR and aerophotogrammetry in the context of building extraction and briefly discusses a photogrammetric strategy for refining building roof polyhedrons previously extracted from LiDAR data. In general, empirical and theoretical studies have confirmed that LiDAR-based methodologies are more suitable in extracting planar roof faces and ridges of the roof, whereas the aerophotogrammetry are more suitable in extracting building roof outlines. In order to exemplify how to explore these properties, it is presented a photogrammetric method for refining 3D building roof contours extracted from airborne LiDAR data. Examples of application are provided for this refining approach.

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

    OpenAIRE

    Cheng-Kai Wang; Yi-Hsing Tseng; Hone-Jay Chu

    2014-01-01

    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 co...

  5. Salih Zeki ve Darülfünun

    OpenAIRE

    Dölen, Emre

    2011-01-01

      Salih Zeki and the Darülfünun Emre Dölen Salih Zeki had a productive life in science, education and philosophy. He wrote textbooks for high schools on algebra, geometry, physics and astronomy between 1882 and 1908. This period refers also to his intensive work on history and philosophy of mathematics when he also realized his major project Kamus-i Riyaziyat, a 12-volume lexicon of mathematical sciences. Starting to lecture on mathematics and physics soon after the establishment of the ...

  6. 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 ...

  7. Astrobiologische Experimente im Erdorbit und darüber hinaus

    OpenAIRE

    Rettberg, Petra

    2016-01-01

    Astrobiologie ist eine interdisziplinäre Naturwissenschaft, die sich mit Fragen zum Ursprung und zur Entwicklung des Lebens auf der Erde befasst und herausfinden möchte, ob und wo Leben außerhalb der Erde existiert oder existieren könnte. Mikroorganismen waren die ersten Lebewesen auf der Erde. Auch heute besiedeln sie in einer sehr großen Anzahl und Diversität alle Lebensräume auf der Erde und stellen somit die erfolgreichste Gruppe von Organismen dar. In der Arbeitsgruppe Astrobiologie im I...

  8. 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.

  9. Identifying Colluvial Slopes by Airborne LiDAR Analysis

    Science.gov (United States)

    Kasai, M.; Marutani, T.; Yoshida, H.

    2015-12-01

    Colluvial slopes are one of major sources of landslides. Identifying the locations of the slopes will help reduce the risk of disasters, by avoiding building infrastructure and properties nearby, or if they are already there, by applying appropriate counter measures before it suddenly moves. In this study, airborne LiDAR data was analyzed to find their geomorphic characteristics to use for extracting their locations. The study site was set in the suburb of Sapporo City, Hokkaido in Japan. The area is underlain by Andesite and Tuff and prone to landslides. Slope angle and surface roughness were calculated from 5 m resolution DEM. These filters were chosen because colluvial materials deposit at around the angle of repose and accumulation of loose materials was considered to form a peculiar surface texture differentiable from other slope types. Field survey conducted together suggested that colluvial slopes could be identified by the filters with a probability of 80 percent. Repeat LiDAR monitoring of the site by an unmanned helicopter indicated that those slopes detected as colluviums appeared to be moving at a slow rate. In comparison with a similar study from the crushed zone in Japan, the range of slope angle indicative of colluviums agreed with the Sapporo site, while the texture was rougher due to larger debris composing the slopes.

  10. 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...

  11. ¿Es la psiquiatría una ciencia?.

    Directory of Open Access Journals (Sweden)

    Francesc Roca i Sebastià

    1999-01-01

    Full Text Available No es habitual la elección de una pregunta como título, y menos una pregunta que entra en conflicto con una verdad tenida por obvia y comúnmente aceptada. No obstante la he elegido para introducir un artículo en el que trataré de dar cuenta de una hipótesis con la que pretendo cuestionarme justamente lo obvio de esta verdad de aceptación común, especialmente en lo que a la práctica clínica de la psiquiatría se refiere, y sus consecuencias: considero que, en la época de la técnica en la que vivimos, la clínica médica, y por tanto también la práctica clínica de la psiquiatría, está comprometida en sí misma, presa de la contradicción en la que nace como modo de practicar la medicina, la exclusión en dicha práctica del enfermo en tanto que sujeto capaz de narrar su propia historia, capaz de darse a sí mismo un tiempo subjetivo distinto de la mera cronología, lo que hace que su existencia tenga un valor distinto al del fenómeno.

  12. Diseño y contraste de nuevos modelos de estimación del potencial energético de biomasa forestal en el Territorio de Bizkaia mediante técnicas de análisis estadístico espacial usando herramientas GIS con datos LiDAR

    OpenAIRE

    Torre Tojal, Leyre

    2016-01-01

    RESUMEN: El objetivo de esta tesis doctoral es desarrollar un modelo que permita estimar la biomasa aérea para la especie Pinus radiata en la comarca de Arratia-Nervión, (Bizkaia), a partir del uso exclusivo de los datos del vuelo LiDAR realizado por Gobierno Vasco en 2012. En el proceso, se han utilizado los datos de campo del Inventario Forestal Nacional 4 como base para estimar la biomasa de contraste. Partiendo de las nubes de puntos LiDAR y tras su procesado, se han calculado diversa...

  13. 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...

  14. 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...

  15. 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

  16. Tree crown delineation from high resolution airborne LiDAR based on densities of high points

    NARCIS (Netherlands)

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

    2009-01-01

    Tree detection and tree crown delineation from Airborne LiDAR has been focusing mostly on utilizing the canopy height model (CHM). This paper presents a method for individual tree crown delineation based on densities of high points (DHP) from the high resolution Airborne LiDAR. The DHP method relies

  17. 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...

  18. 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

  19. 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...

  20. 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...

  1. 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...

  2. 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

  3. 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.

  4. 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.

  5. The use of airborne LiDAR data for the analysis of debris flow events in Switzerland

    OpenAIRE

    C. Scheidl; D. Rickenmann; M. Chiari

    2008-01-01

    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 d...

  6. In Situ Vitrification Engineering-Scale Test ES-INEL-4, ES-INEL-5, ES-INEL-6, and ES-INEL-7 Test Plan

    International Nuclear Information System (INIS)

    The In Situ Vitrification Engineering-Scale Tests ES-4, ES-5, ES-6, and ES-7 Product Characterization Test Plan describes the methods and procedures to be used or the physical and chemical characterization of the solid product(s) resulting from the Idaho National Engineering Laboratory engineering scale in situ vitrification tests ES-4, ES-5, ES-6, and ES-7. The goals of this Test Plan are to insure that the product characterization results are sufficient to meet the data needs of the In Situ Vitrification Program and are technically and legally defensible. Important issues addressed by the test plan include sampling and analysis strategy, sampling procedures, laboratory analysis, sample control and document management, equipment, data reporting and validation, quality assurance, specific routine procedures to assess data representativeness, safety and training program, and data management. 9 refs., 1 fig., 3 tabs

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. Advances in animal ecology from 3D ecosystem mapping with LiDAR

    Science.gov (United States)

    Davies, A.; Asner, G. P.

    2015-12-01

    The advent and recent advances of Light Detection and Ranging (LiDAR) have enabled accurate measurement of 3D ecosystem structure. Although the use of LiDAR data is widespread in vegetation science, it has only recently (animal ecology. Despite such recent application, LiDAR has enabled new insights in the field and revealed the fundamental importance of 3D ecosystem structure for animals. We reviewed the studies to date that have used LiDAR in animal ecology, synthesising the insights gained. Structural heterogeneity is most conducive to increased animal richness and abundance, and increased complexity of vertical vegetation structure is more positively influential than traditionally measured canopy cover, which produces mixed results. However, different taxonomic groups interact with a variety of 3D canopy traits and some groups with 3D topography. LiDAR technology can be applied to animal ecology studies in a wide variety of environments to answer an impressive array of questions. Drawing on case studies from vastly different groups, termites and lions, we further demonstrate the applicability of LiDAR and highlight new understanding, ranging from habitat preference to predator-prey interactions, that would not have been possible from studies restricted to field based methods. We conclude with discussion of how future studies will benefit by using LiDAR to consider 3D habitat effects in a wider variety of ecosystems and with more taxa to develop a better understanding of animal dynamics.

  12. Automatic registration of UAV-borne sequent images and LiDAR data

    Science.gov (United States)

    Yang, Bisheng; Chen, Chi

    2015-03-01

    Use of direct geo-referencing data leads to registration failure between sequent images and LiDAR data captured by mini-UAV platforms because of low-cost sensors. This paper therefore proposes a novel automatic registration method for sequent images and LiDAR data captured by mini-UAVs. First, the proposed method extracts building outlines from LiDAR data and images and estimates the exterior orientation parameters (EoPs) of the images with building objects in the LiDAR data coordinate framework based on corresponding corner points derived indirectly by using linear features. Second, the EoPs of the sequent images in the image coordinate framework are recovered using a structure from motion (SfM) technique, and the transformation matrices between the LiDAR coordinate and image coordinate frameworks are calculated using corresponding EoPs, resulting in a coarse registration between the images and the LiDAR data. Finally, 3D points are generated from sequent images by multi-view stereo (MVS) algorithms. Then the EoPs of the sequent images are further refined by registering the LiDAR data and the 3D points using an iterative closest-point (ICP) algorithm with the initial results from coarse registration, resulting in a fine registration between sequent images and LiDAR data. Experiments were performed to check the validity and effectiveness of the proposed method. The results show that the proposed method achieves high-precision robust co-registration of sequent images and LiDAR data captured by mini-UAVs.

  13. Applications of High-Resolution LiDAR Data for the Christina River Basin CZO

    Science.gov (United States)

    Hicks, N. S.; Aufdenkampe, A. K.; Hicks, S. D.

    2011-12-01

    High-resolution LiDAR data allows for fine scale geomorphic assessment over relatively large spatial extents. Previously available DEMs with a resolution of ten meters or more did not provide adequate resolution for geomorphic characterization of small streams and watersheds or the identification of changes in stream morphology over time. High-resolution LiDAR data for a portion of the Christina River Basin Critical Zone Observatory (CRB-CZO) was obtained during both leaf-off and leaf-on time periods in 2010. Topographic data from these flights is being analyzed with the intent of geomorphic applications such as stream morphology, sediment transport studies, and the evaluation of alluvial deposits. These data and resultant products will also be used in hydrologic and biogeochemical modeling and in biologic and biogeochemical studies of these streams, which are long-term study sites. The LiDAR data also facilitate informed instrument placement and will be used for vegetation studies. The LiDAR data for the CRB-CZO has been used to create a variety of LiDAR based topographic data products including TINs and 0.5-m DEMs. LiDAR derived slope and elevation products were combined with LiDAR intensity images to identify stream channel boundaries and stream centerlines for third through first-order streams. High-resolution slope data also aided in floodplain characterization of these small streams. These high precision stream channel and floodplain characterizations would not have been otherwise possible without extensive field surveying. Future LiDAR flights will allow for the identification of changes in channel morphology over time in low order basins. These characterizations are of particular interest in comparisons between forested and meadow reaches, and in studying the effects of changes in land-use on channel morphology. High-resolution LiDAR data allow for the generation of surface characterizations of importance to a wide range of interdisciplinary researchers.

  14. Using LiDAR data to define stream flow rating curves

    OpenAIRE

    Nathanson, Marcus; Jason W. Kean; Laudon, Hjalmar; Seibert, Jan; Grabs, Thomas; Lyon, Steve W

    2012-01-01

    In remote locations, it is difficult to obtain stream flow information because of the difficulty making sufficient dis- charge measurements. In this study we investigate the feasibility to constrain a fluid mechanics-based flow model for defining stream flow rating curves with remotely sensed topographic data from airborne LiDAR scanning. A near infrared (NIR) LiDAR scan was carried out for an 8-m wide channel in northern Sweden. The topographic information from this NIR LiDAR scan along the ...

  15. Lava flow identification and ageing by means of LiDAR intensity: the Mt. Etna case

    OpenAIRE

    Mazzarini, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia; Pareschi, M. T.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia; Favalli, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia; Isola, I.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia; Tarquini, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia; Boschi, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione AC, Roma, Italia

    2006-01-01

    An application of LiDAR (Light Detection and Ranging) intensity for the identification and mapping of different lava flows from the Mt. Etna (Italy) active volcano is described. In September 2004 an airborne LiDAR survey was flown over summit sectors of Mt. Etna. The information derived from LiDAR intensity values was used to compare the lava flows with respect to their age of emplacement. Analysed lava flows vary in age between those dating prior to AD 1610 and those active du...

  16. 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

  17. Forest Roads Mapped Using LiDAR in Steep Forested Terrain

    OpenAIRE

    Russell A. White; Brian C. Dietterick; Thomas Mastin; Rollin Strohman

    2010-01-01

    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...

  18. 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...

  19. Flood Modeling Using a Synthesis of Multi-Platform LiDAR Data

    OpenAIRE

    Ryan M. Csontos; Jeffrey D. Colby; Ashleigh B. Turner; Michael Batten

    2013-01-01

    This study examined the utility of a high resolution ground-based (mobile and terrestrial) Light Detection and Ranging (LiDAR) dataset (0.2 m point-spacing) supplemented with a coarser resolution airborne LiDAR dataset (5 m point-spacing) for use in a flood inundation analysis. The techniques for combining multi-platform LiDAR data into a composite dataset in the form of a triangulated irregular network (TIN) are described, and quantitative comparisons were made to a TIN generated solely from...

  20. Application of airborne LiDAR in river environments: the River Coquet, Northumberland, UK

    OpenAIRE

    Charlton, Martin; Large, A.; Fuller, I.

    2003-01-01

    The potential offered by LiDAR (laser-induced direction and ranging) for the mapping of gravel-bed river environments is addressed in this paper. A LiDAR dataset was obtained for a reach of the River Coquet, Northumberland, UK. Topographic data were acquired from the field at the same time using theodolite-EDM survey of a number of cross-profiles across the active river channel and bar units. These cross-profiles provide a means of comparing measurements from the LiDAR data with g...

  1. LiDAR Forest Inventory with Single-Tree, Double-, and Single-Phase Procedures

    OpenAIRE

    Parker, Robert C.; Evans, David L.

    2009-01-01

    Light Detection and Ranging (LiDAR) data at 0.5–2 m postings were used with double-sample, stratified procedures involving single-tree relationships in mixed, and single species stands to yield sampling errors ranging from ± 2 . 1 % to ± 1 1 . 5 %. LiDAR samples were selected with focal filter procedures and heights computed from interpolated canopy and DEM surfaces. Tree dbh and height data were obtained at various ratios of LiDAR, ground samples for DGPS located ground plots. Dbh-height and...

  2. The Use of LiDAR Terrain Data in Characterizing Surface Roughness and Microtopography

    OpenAIRE

    Brubaker, Kristen M.; Myers, Wayne L.; Drohan, Patrick J.; Miller, Douglas A.; Boyer, Elizabeth W.

    2013-01-01

    The availability of light detection and ranging data (LiDAR) has resulted in a new era of landscape analysis. For example, improvements in LiDAR data resolution may make it possible to accurately model microtopography over a large geographic area; however, data resolution and processing costs versus resulting accuracy may be too costly. We examined two LiDAR datasets of differing resolutions, a low point density (0.714 points/m2 spacing) 1 m DEM available statewide in Pennsylvania and a high ...

  3. Potential of a terrestrial LiDAR-based system to characterise weed vegetation in maize crops

    OpenAIRE

    Andújar, Dionisio; Escolà i Agustí, Alexandre; Rosell Polo, Joan Ramon; Fernández-Quintanilla, César; Dorado, José

    2013-01-01

    LiDAR (Light Detection And Ranging) is a remote-sensing technique for the measurement of the distance between the sensor and a target. A LiDAR-based detection procedure was tested for characterisation of the weed vegetation present in the inter-row area of a maize field. This procedure was based on the hypothesis that weed species with different heights can be precisely detected and discriminated using non-contact ranging sensors such as LiDAR. The sensor was placed in the front of an all-ter...

  4. 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

  5. El audiovisual como herramienta para dar a conocer la biblioteca.

    OpenAIRE

    Dueñas Herrero, Arturo

    2014-01-01

    Las bibliotecas han sido escenario de multitud de secuencias en pel??culas de ficci??n, dejando casi siempre una impresi??n de sitio cerrado, reservado para unos elegidos y vigilado por celosos(celosas, m??s bien) guardianes. Esta concepci??n tradicional ha ido cambiando para transmitir la idea de que la misi??n principal de las bibliotecas no es custodiar, sino difundir el conocimiento, m??s a??n en el caso de las bibliotecas universitarias, cuyo cometido es servir de apoyo a las tareas de d...

  6. 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...

  7. 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...

  8. 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.

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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.

  17. 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...

  18. 2006 U.S. Geological Survey Topographic LiDAR: Alameda County

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) data set is a survey of Alameda County in Northern California. The entire survey covers approximately 868.382 square miles....

  19. LiDAR improves fire behaviour predictions using a biophysical, mechanistic model

    Science.gov (United States)

    Zylstra, Philip; Horsey, Bronwyn; Yebra, Marta; Marselis, Suzanne

    2016-04-01

    Numerous studies have attempted to address the utility of LiDAR as a tool for measuring fuel inputs to fire behaviour models, however the direct effect of this approach on fire behaviour prediction requires quantification. We used a biophysical, mechanistic model validated for eucalypt forest in SE Australia to assess the improvement in prediction accuracy afforded using LiDAR-derived inputs. The accuracy of modelling with these inputs was compared to modelling using detailed site-specific field surveys of a dry sclerophyll forest to represent the highest standard of inputs, and values derived from desktop-available community-wide descriptors to represent baseline inputs. Use of LiDAR significantly improved on baseline predictions and enabled site-specific decision making across the study area. When used with an appropriate model, LiDAR can facilitate improved decision-making in regard to forest fire behaviour.

  20. 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...

  1. 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....

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. LiDAR-mast deviations in complex terrain and their simulation using CFD

    Directory of Open Access Journals (Sweden)

    Tobias Klaas

    2015-11-01

    Full Text Available LiDARs (Light Detection and Ranging are becoming important tools for wind resource assessments in all kinds of terrain. Compared to mast measurements, mobility and flexibility are their greatest benefits. However, care needs to be taken when setting up a measurement campaign. The influence of complex terrain on the wind leads to inhomogeneous flow. This can cause considerable errors in ground based mono-static LiDAR measurements due to their measurement principle and simplifying assumptions.Within this work, wind measurements from Fraunhofer IWES’s 200 m research mast in complex terrain at “Rödeser Berg” in Kassel, Germany, and a pulsed Doppler LiDAR (Leosphere windcube, located at the mast, are compared. The relative deviation between the measurements of the horizontal wind speed by the LiDAR and the mast (LiDAR-mast deviations varies with wind direction and height. It ranges from about −4 % underestimation to +2.5 % overestimation by the LiDAR - for heights between 120 and 200 m. Two steady-state Reynolds-Averaged-Navier-Stokes (RANS Computational Fluid Dynamics (CFD-models and a model based on linearized Navier-Stokes Equations were used to estimate the LiDAR error from a flow simulation. Model results were evaluated depending on model parameterisation such as forest height and density. Given the right parameterisations – especially for the forest model – the CFD-models showed a good performance when compared to the observed LiDAR-mast deviations. These simulations can thus be used to correct the LiDAR error induced by the complex flow.To demonstrate variations of LiDAR errors due to choice of measurement location, one of the models was run to calculate the wind flow in an area of 2×2km2$2\\times2\\,\\text{km}^{2}$ around the 200 m measurement mast. This allows the visualization of the estimated LiDAR errors to characterize measurement locations. Results showed the significant variation of measurement errors due to

  10. Improving Species Diversity and Biomass Estimates of Tropical Dry Forests Using Airborne LiDAR

    OpenAIRE

    José Luis Hernández-Stefanoni; Juan Manuel Dupuy; Johnson, Kristofer D; Richard Birdsey; Fernando Tun-Dzul; Alicia Peduzzi; Juan Pablo Caamal-Sosa; Gonzalo Sánchez-Santos; David López-Merlín

    2014-01-01

    The spatial distribution of plant diversity and biomass informs management decisions to maintain biodiversity and carbon stocks in tropical forests. Optical remotely sensed data is often used for supporting such activities; however, it is difficult to estimate these variables in areas of high biomass. New technologies, such as airborne LiDAR, have been used to overcome such limitations. LiDAR has been increasingly used to map carbon stocks in tropical forests, but has rarely been used to esti...

  11. Using Light Detection and Ranging (LiDAR) Imagery To Model Radio Wave Propagation

    OpenAIRE

    Cash, Jason M

    2003-01-01

    The purpose of this study was to determine if light detection and ranging (LiDAR) imagery could provide a significantly more accurate data set for modeling near line-of-sight (LOS) propagation at higher frequencies, specifically 27.810 GHz. than a USGS digital elevation model (DEM). In addition, the study tested for significant differences in LiDAR elevation data created at various resolutions ranging from 1 to 100 meters. Finally, this study examined the effects of various classification t...

  12. Hierarchical Registration Method for Airborne and Vehicle LiDAR Point Cloud

    OpenAIRE

    Liang Cheng; Yang Wu; Lihua Tong; Yanming Chen; Manchun Li

    2015-01-01

    A new hierarchical method for the automatic registration of airborne and vehicle light detection and ranging (LiDAR) data is proposed, using three-dimensional (3D) road networks and 3D building contours. Firstly, 3D road networks are extracted from airborne LiDAR data and then registered with vehicle trajectory lines. During the registration of airborne road networks and vehicle trajectory lines, a network matching rate is introduced for the determination of reliable transformation matrix. Th...

  13. Ground Filtering Algorithms for Airborne LiDAR Data: A Review of Critical Issues

    OpenAIRE

    Kaiguang Zhao; Nate Currit; Xuelian Meng

    2010-01-01

    This paper reviews LiDAR ground filtering algorithms used in the process of creating Digital Elevation Models. We discuss critical issues for the development and application of LiDAR ground filtering algorithms, including filtering procedures for different feature types, and criteria for study site selection, accuracy assessment, and algorithm classification. This review highlights three feature types for which current ground filtering algorithms are suboptimal, and which can be improved upon...

  14. A Comparison of Two Open Source LiDAR Surface Classification Algorithms

    OpenAIRE

    Danny G Marks; Nancy F. Glenn; Timothy E. Link; Hudak, Andrew T.; Rupesh Shrestha; Michael J. Falkowski; Alistair M. S. Smith; Hongyu Huang; Wade T. Tinkham

    2011-01-01

    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 openly available, free to use, and are supported by published results. Two of the latter are the multiscale curvature classification and the Boise Center Aerospace Laboratory LiDAR (BCAL) algorithms....

  15. Land Cover Classification Accuracy Assessment Using Full-Waveform LiDAR Data

    OpenAIRE

    Kuan-Tsung Chang; Feng-Chi Yu; Yi Chang; Jin-Tsong Hwang; Jin-King Liu; Wei-Chen Hsu; and Peter Tian-Yuan Shih

    2015-01-01

    The geomorphology of Taiwan is characterized by marked changes in terrain, geological fractures, and frequent natural disasters. Because of sustained economic growth, urbanization and land development, the land cover in Taiwan has undergone frequent use changes. Among the various technologies for monitoring changes in land cover, remote sensing technologies, such as LiDAR, are efficient tools for collecting a broad range of spectral and spatial data. Two types of airborne LiDAR systems exist;...

  16. A Comparative Study between Frequency-Modulated Continous Wave LADAR and Linear LiDAR

    OpenAIRE

    R. D. Massaro; Anderson, J E; Nelson, J. D.; Edwards, J D

    2014-01-01

    Topographic Light Detection and Ranging (LiDAR) technology has advanced greatly in the past decade. Pulse repetition rates of terrestrial and airborne systems havemultiplied thus vastly increasing data acquisition rates. Geiger-mode and FLASH LiDAR have also become far more mature technologies. However, a new and relatively unknown technology is maturing rapidly: Frequency-Modulated Continuous Wave Laser Detection and Ranging (FMCW-LADAR). Possessing attributes more akin to modern ra...

  17. Evaluation of automatic building detection approaches combining high resolution images and LiDAR data

    OpenAIRE

    Javier Estornell; Recio, Jorge A.; Txomin Hermosilla; Ruiz, Luis A.

    2011-01-01

    In this paper, two main approaches for automatic building detection and localization using high spatial resolution imagery and LiDAR data are compared and evaluated: thresholding-based and object-based classification. The thresholding-based approach is founded on the establishment of two threshold values: one refers to the minimum height to be considered as building, defined using the LiDAR data, and the other refers to the presence of vegetation, which is defined according to the spectral re...

  18. Engineering monitoring of rockfall hazards along transportation corridors: using mobile terrestrial LiDAR

    OpenAIRE

    M. Lato; Hutchinson, J.; Diederichs, M.; Ball, D.; Harrap, R.

    2009-01-01

    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 ...

  19. Characterisation of the surface morphology of an alpine alluvial fan using airborne LiDAR

    OpenAIRE

    M. Cavalli; L. Marchi

    2008-01-01

    International audience Alluvial fans of alpine torrents are both natural deposition areas for sediment discharged by floods and debris flows, and preferred sites for agriculture and settlements. Hazard assessment on alluvial fans depends on proper identification of flow processes and their potential intensity. This study used LiDAR data to examine the morphology of the alluvial fan of a small alpine stream (Moscardo Torrent, Eastern Italian Alps). A high-resolution DTM from LiDAR data was ...

  20. AN EFFICIENT METHOD FOR AUTOMATIC ROAD EXTRACTION BASED ON MULTIPLE FEATURES FROM LiDAR DATA

    OpenAIRE

    Li, Y.; Hu, X.; H. Guan; Liu, P.

    2016-01-01

    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...

  1. Shiftable Leading Point Method for High Accuracy Registration of Airborne and Terrestrial LiDAR Data

    OpenAIRE

    Liang Cheng; Lihua Tong; Yang Wu; Yanming Chen; Manchun Li

    2015-01-01

    A new automated approach to the high-accuracy registration of airborne and terrestrial LiDAR data is proposed, which has three primary steps. Firstly, airborne and terrestrial LiDAR data are used to extract building corners, known as airborne corners and terrestrial corners, respectively. Secondly, an initial matching relationship between the terrestrial corners and airborne corners is automatically derived using a matching technique based on maximum matching corner pairs with minimum errors ...

  2. Object-Based Classification of Abandoned Logging Roads under Heavy Canopy Using LiDAR

    OpenAIRE

    Jason Sherba; Leonhard Blesius; Jerry Davis

    2014-01-01

    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 th...

  3. Sexual behaviours and associated factors among students at Bahir Dar University: a cross sectional study

    OpenAIRE

    Mulu, Wondemagegn; Yimer, Mulat; Abera, Bayeh

    2014-01-01

    Background Sexual behaviour is the core of sexuality matters in adolescents and youths. Their modest or dynamic behaviour vulnerable them to risky sexual behaviours. In Ethiopia, there is scarcity of multicentered representative data on sexual behaviours in students to have a national picture at higher education. This study therefore conducted to assess sexual behaviours and associated factors at Bahir Dar University, Ethiopia. Methods A cross sectional study was conducted among Bahir Dar Uni...

  4. Es la marihuana una droga maldita?

    OpenAIRE

    Peña, Jaime

    2010-01-01

    Con curiosidad hemos observado que en el último año han aparecido numerosas publicaciones en revistas de reconocido prestigio médico científico en la que se hacen planteamientos acerca de un posible papel terapéutico de la Cannabis sativa, más conocida como marihuana. Parece que esta polémica planta, famosa en Colombia por ocupar un lugar destacado entre las "exportaciones no tradicionales", está reuniendo argumentos para dar el gran salto al privilegiado grupo de las "Plantas Medicinales"....

  5. 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.

  6. 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.

  7. 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.

  8. Area-Based Mapping of Defoliation of Scots Pine Stands Using Airborne Scanning LiDAR

    Directory of Open Access Journals (Sweden)

    Hannu Hyyppä

    2013-03-01

    Full Text Available The mapping of changes in the distribution of insect-caused forest damage remains an important forest monitoring application and challenge. Efficient and accurate methods are required for mapping and monitoring changes in insect defoliation to inform forest management and reporting activities. In this research, we develop and evaluate a LiDAR-driven (Light Detection And Ranging approach for mapping defoliation caused by the Common pine sawfly (Diprion pini L.. Our method requires plot-level training data and airborne scanning LiDAR data. The approach is predicated on a forest canopy mask created by detecting forest canopy cover using LiDAR. The LiDAR returns that are reflected from the canopy (that is, returns > half of maximum plot tree height are used in the prediction of the defoliation. Predictions of defoliation are made at plot-level, which enables a direct integration of the method to operational forest management planning while also providing additional value-added from inventory-focused LiDAR datasets. In addition to the method development, we evaluated the prediction accuracy and investigated the required pulse density for operational LiDAR-based mapping of defoliation. Our method proved to be suitable for the mapping of defoliated stands, resulting in an overall mapping accuracy of 84.3% and a Cohen’s kappa coefficient of 0.68.

  9. 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.

  10. 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.

  11. 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

  12. Independent evaluation of the SNODAS snow depth product using regional scale LiDAR-derived measurements

    Directory of Open Access Journals (Sweden)

    A. Hedrick

    2014-06-01

    Full Text Available Repeated Light Detection and Ranging (LiDAR surveys are quickly becoming the de facto method for measuring spatial variability of montane snowpacks at high resolution. This study examines the potential of a 750 km2 LiDAR-derived dataset of snow depths, collected during the 2007 northern Colorado Cold Lands Processes Experiment (CLPX-2, as a validation source for an operational hydrologic snow model. The SNOw Data Assimilation System (SNODAS model framework, operated by the US National Weather Service, combines a physically-based energy-and-mass-balance snow model with satellite, airborne and automated ground-based observations to provide daily estimates of snowpack properties at nominally 1 km resolution over the coterminous United States. Independent validation data is scarce due to the assimilating nature of SNODAS, compelling the need for an independent validation dataset with substantial geographic coverage. Within twelve distinctive 500 m × 500 m study areas located throughout the survey swath, ground crews performed approximately 600 manual snow depth measurements during each of the CLPX-2 LiDAR acquisitions. This supplied a dataset for constraining the uncertainty of upscaled LiDAR estimates of snow depth at the 1 km SNODAS resolution, resulting in a root-mean-square difference of 13 cm. Upscaled LiDAR snow depths were then compared to the SNODAS-estimates over the entire study area for the dates of the LiDAR flights. The remotely-sensed snow depths provided a more spatially continuous comparison dataset and agreed more closely to the model estimates than that of the in situ measurements alone. Finally, the results revealed three distinct areas where the differences between LiDAR observations and SNODAS estimates were most drastic, suggesting natural processes specific to these regions as causal influences on model uncertainty.

  13. 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.

  14. Improved estimates of forest vegetation structure and biomass with a LiDAR-optimized sampling design

    Science.gov (United States)

    Hawbaker, Todd J.; Keuler, Nicholas S.; Lesak, Adrian A.; Gobakken, Terje; Contrucci, Kirk; Radeloff, Volker C.

    2009-06-01

    LiDAR data are increasingly available from both airborne and spaceborne missions to map elevation and vegetation structure. Additionally, global coverage may soon become available with NASA's planned DESDynI sensor. However, substantial challenges remain to using the growing body of LiDAR data. First, the large volumes of data generated by LiDAR sensors require efficient processing methods. Second, efficient sampling methods are needed to collect the field data used to relate LiDAR data with vegetation structure. In this paper, we used low-density LiDAR data, summarized within pixels of a regular grid, to estimate forest structure and biomass across a 53,600 ha study area in northeastern Wisconsin. Additionally, we compared the predictive ability of models constructed from a random sample to a sample stratified using mean and standard deviation of LiDAR heights. Our models explained between 65 to 88% of the variability in DBH, basal area, tree height, and biomass. Prediction errors from models constructed using a random sample were up to 68% larger than those from the models built with a stratified sample. The stratified sample included a greater range of variability than the random sample. Thus, applying the random sample model to the entire population violated a tenet of regression analysis; namely, that models should not be used to extrapolate beyond the range of data from which they were constructed. Our results highlight that LiDAR data integrated with field data sampling designs can provide broad-scale assessments of vegetation structure and biomass, i.e., information crucial for carbon and biodiversity science.

  15. 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.

  16. Diversity arrays technology (DArT) for high-throughput profiling of the hexaploid wheat genome.

    Science.gov (United States)

    Akbari, Mona; Wenzl, Peter; Caig, Vanessa; Carling, Jason; Xia, Ling; Yang, Shiying; Uszynski, Grzegorz; Mohler, Volker; Lehmensiek, Anke; Kuchel, Haydn; Hayden, Mathew J; Howes, Neil; Sharp, Peter; Vaughan, Peter; Rathmell, Bill; Huttner, Eric; Kilian, Andrzej

    2006-11-01

    Despite a substantial investment in the development of panels of single nucleotide polymorphism (SNP) markers, the simple sequence repeat (SSR) technology with a limited multiplexing capability remains a standard, even for applications requiring whole-genome information. Diversity arrays technology (DArT) types hundreds to thousands of genomic loci in parallel, as previously demonstrated in a number diploid plant species. Here we show that DArT performs similarly well for the hexaploid genome of bread wheat (Triticum aestivum L.). The methodology previously used to generate DArT fingerprints of barley also generated a large number of high-quality markers in wheat (99.8% allele-calling concordance and approximately 95% call rate). The genetic relationships among bread wheat cultivars revealed by DArT coincided with knowledge generated with other methods, and even closely related cultivars could be distinguished. To verify the Mendelian behaviour of DArT markers, we typed a set of 90 Cranbrook x Halberd doubled haploid lines for which a framework (FW) map comprising a total of 339 SSR, restriction fragment length polymorphism (RFLP) and amplified fragment length polymorphism (AFLP) markers was available. We added an equal number of DArT markers to this data set and also incorporated 71 sequence tagged microsatellite (STM) markers. A comparison of logarithm of the odds (LOD) scores, call rates and the degree of genome coverage indicated that the quality and information content of the DArT data set was comparable to that of the combined SSR/RFLP/AFLP data set of the FW map. PMID:17033786

  17. Improving Low-Relief Coastal LiDAR DEMs with Hydro-Conditioning of Fine-Scale and Artificial Drainages

    OpenAIRE

    Allen, Thomas R.; Howard, Robert

    2015-01-01

    Improvements in Light Detection and Ranging (LiDAR) technology and spatial analysis of high-resolution digital elevation models (DEMs) have advanced the accuracy and diversity of applications for coastal hazards and natural resources management. This article presents a concise synthesis of LiDAR analysis for coastal flooding and management applications in low-relief coastal plains and a case study demonstration of a new, efficient drainage mapping algorithm. The impetus for these LiDAR applic...

  18. Estimation of shub height for fuel-type mapping combining airborne LiDAR and simultaneous color infrared ortho imaging

    OpenAIRE

    Ria??o, David; Chuvieco, Emilio; Susan L Ustin; Salas, Javier; Ridr??guez P??rez, Jos?? Ram??n; Ribeiro, Luis M.; Viegas, Domingos X.; Moreno, Jos?? M.; Fern??ndez, Helena

    2007-01-01

    P. 341-348 A fuel-type map of a predominantly shub-land area in central Portugal was generated for a fire research experimental site, by combining airborne light detection and ranging (LiDAR), and simultaneous color infrared ortho imaging. Since the vegetation canopy and the ground are too close together to be easily discerned by LiDAR pulses, standard of processing LiDAR data did not provide an accurate estimate of shrub height

  19. Improving low-relief coastal LiDAR DEMs with hydro-conditioning of fine-scale and artificial drainages

    OpenAIRE

    Thomas Richard Allen; Robert eHoward

    2015-01-01

    Improvements in Light Detection and Ranging (LiDAR) technology and spatial analysis of high-resolution digital elevation models (DEMs) have advanced the accuracy and diversity of applications for coastal hazards and natural resources management. This article presents a concise synthesis of LiDAR analysis for coastal flooding and management applications in low-relief coastal plains and a case study demonstration of a new, efficient drainage mapping algorithm. The impetus for these LiDAR appli...

  20. 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 ...

  1. Geometric Calibration and Radiometric Correction of LiDAR Data and Their Impact on the Quality of Derived Products

    OpenAIRE

    Wai-Yeung Yan; Ahmed Shaker; Habib, Ayman F.; Kersting, Ana P.

    2011-01-01

    LiDAR (Light Detection And Ranging) systems are capable of providing 3D positional and spectral information (in the utilized spectrum range) of the mapped surface. Due to systematic errors in the system parameters and measurements, LiDAR systems require geometric calibration and radiometric correction of the intensity data in order to maximize the benefit from the collected positional and spectral information. This paper presents a practical approach for the geometric calibration of LiDAR sys...

  2. Process-based hierarchical models for coupling high-dimensional LiDAR and forest variables over large geographic domains

    OpenAIRE

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

    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 spatially misaligned LiDAR signals and forest variables. We propose a fully process-based Bayesian hierarchical model for above ground biomass (AGB) and LiDAR signals. The pro...

  3. INS/GPS/LiDAR Integrated Navigation System for Urban and Indoor Environments Using Hybrid Scan Matching Algorithm

    OpenAIRE

    Yanbin Gao; Shifei Liu; Mohamed M. Atia; Aboelmagd Noureldin

    2015-01-01

    This paper takes advantage of the complementary characteristics of Global Positioning System (GPS) and Light Detection and Ranging (LiDAR) to provide periodic corrections to Inertial Navigation System (INS) alternatively in different environmental conditions. In open sky, where GPS signals are available and LiDAR measurements are sparse, GPS is integrated with INS. Meanwhile, in confined outdoor environments and indoors, where GPS is unreliable or unavailable and LiDAR measurements are rich, ...

  4. 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...

  5. Characterisation of Single Wind Turbine Wakes with Static and Scanning WINTWEX-W LiDAR Data

    OpenAIRE

    Kumer, Valerie-Marie; Reuder, Joachim; Svardal, Benny; Sætre, Camilla; Eecen, Peter

    2015-01-01

    With further development of LiDAR technology wake measurements by use of LiDAR became of common interest in the wind energy community. To study new measurement strategies of scanning and nacelle LiDARs, in combination with already existing measurement principles of static LiDARs, Norcowe conducted in collaboration with the Energy research Centre of the Netherlands (ECN) the Wind Turbine Wake Experiment Wieringermeer (WINTWEX-W). In this study we use data from the static Windcubes V1 to illust...

  6. Analysis of full-waveform LiDAR data for forestry applications: a review of investigations and methods

    OpenAIRE

    Pirotti F

    2011-01-01

    The goal of this review is to present leading examples of current methodologies for extracting forest characteristics from full-waveform LiDAR data. Four key questions are addressed: (i) does full-waveform LiDAR provide advantages over discrete-return laser sensors; (ii) will full-waveform LiDAR provide valid results in support of forest inventory operations and allow for a decrease in ground sampling efforts; (iii) is the use of full-waveform LiDAR data cost effective; and (iv) what is the s...

  7. 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

  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. Geotechnical applications of LiDAR pertaining to geomechanical evaluation and hazard identification

    Science.gov (United States)

    Lato, Matthew J.

    Natural hazards related to ground movement that directly affect the safety of motorists and highway infrastructure include, but are not limited to, rockfalls, rockslides, debris flows, and landslides. This thesis specifically deals with the evaluation of rockfall hazards through the evaluation of LiDAR data. Light Detection And Ranging (LiDAR) is an imaging technology that can be used to delineate and evaluate geomechanically-controlled hazards. LiDAR has been adopted to conduct hazard evaluations pertaining to rockfall, rock-avalanches, debris flows, and landslides. Characteristics of LiDAR surveying, such as rapid data acquisition rates, mobile data collection, and high data densities, pose problems to traditional CAD or GIS-based mapping methods. New analyses methods, including tools specifically oriented to geomechanical analyses, are needed. The research completed in this thesis supports development of new methods, including improved survey techniques, innovative software workflows, and processing algorithms to aid in the detection and evaluation of geomechanically controlled rockfall hazards. The scientific research conducted between the years of 2006-2010, as presented in this thesis, are divided into five chapters, each of which has been published by or is under review by an international journal. The five research foci are: (i) geomechanical feature extraction and analysis using LiDAR data in active mining environments; (ii) engineered monitoring of rockfall hazards along transportation corridors: using mobile terrestrial LiDAR; (iii) optimization of LiDAR scanning and processing for automated structural evaluation of discontinuities in rockmasses; (iv) location orientation bias when using static LiDAR data for geomechanical analysis; and (v) evaluating roadside rockmasses for rockfall hazards from LiDAR data: optimizing data collection and processing protocols. The research conducted pertaining to this thesis has direct and significant implications with

  10. Performance Assessment of High Resolution Airborne Full Waveform LiDAR for Shallow River Bathymetry

    Directory of Open Access Journals (Sweden)

    Zhigang Pan

    2015-04-01

    Full Text Available We evaluate the performance of full waveform LiDAR decomposition algorithms with a high-resolution single band airborne LiDAR bathymetry system in shallow rivers. A continuous wavelet transformation (CWT is proposed and applied in two fluvial environments, and the results are compared to existing echo retrieval methods. LiDAR water depths are also compared to independent field measurements. In both clear and turbid water, the CWT algorithm outperforms the other methods if only green LiDAR observations are available. However, both the definition of the water surface, and the turbidity of the water significantly influence the performance of the LiDAR bathymetry observations. The results suggest that there is no single best full waveform processing algorithm for all bathymetric situations. Overall, the optimal processing strategies resulted in a determination of water depths with a 6 cm mean at 14 cm standard deviation for clear water, and a 16 cm mean and 27 cm standard deviation in more turbid water.

  11. Evolutionary feature selection to estimate forest stand variables using LiDAR

    Science.gov (United States)

    Garcia-Gutierrez, Jorge; Gonzalez-Ferreiro, Eduardo; Riquelme-Santos, Jose C.; Miranda, David; Dieguez-Aranda, Ulises; Navarro-Cerrillo, Rafael M.

    2014-02-01

    Light detection and ranging (LiDAR) has become an important tool in forestry. LiDAR-derived models are mostly developed by means of multiple linear regression (MLR) after stepwise selection of predictors. An increasing interest in machine learning and evolutionary computation has recently arisen to improve regression use in LiDAR data processing. Although evolutionary machine learning has already proven to be suitable for regression, evolutionary computation may also be applied to improve parametric models such as MLR. This paper provides a hybrid approach based on joint use of MLR and a novel genetic algorithm for the estimation of the main forest stand variables. We show a comparison between our genetic approach and other common methods of selecting predictors. The results obtained from several LiDAR datasets with different pulse densities in two areas of the Iberian Peninsula indicate that genetic algorithms perform better than the other methods statistically. Preliminary studies suggest that a lack of parametric conditions in field data and possible misuse of parametric tests may be the main reasons for the better performance of the genetic algorithm. This research confirms the findings of previous studies that outline the importance of evolutionary computation in the context of LiDAR analisys of forest data, especially when the size of fieldwork datatasets is reduced.

  12. Detection of fault structures with airborne LiDAR point-cloud data

    Science.gov (United States)

    Chen, Jie; Du, Lei

    2015-08-01

    The airborne LiDAR (Light Detection And Ranging) technology is a new type of aerial earth observation method which can be used to produce high-precision DEM (Digital Elevation Model) quickly and reflect ground surface information directly. Fault structure is one of the key forms of crustal movement, and its quantitative description is the key to the research of crustal movement. The airborne LiDAR point-cloud data is used to detect and extract fault structures automatically based on linear extension, elevation mutation and slope abnormal characteristics. Firstly, the LiDAR point-cloud data is processed to filter out buildings, vegetation and other non-surface information with the TIN (Triangulated Irregular Network) filtering method and Burman model calibration method. TIN and DEM are made from the processed data sequentially. Secondly, linear fault structures are extracted based on dual-threshold method. Finally, high-precision DOM (Digital Orthophoto Map) and other geological knowledge are used to check the accuracy of fault structure extraction. An experiment is carried out in Beiya Village of Yunnan Province, China. With LiDAR technology, results reveal that: the airborne LiDAR point-cloud data can be utilized to extract linear fault structures accurately and automatically, measure information such as height, width and slope of fault structures with high precision, and detect faults in areas with vegetation coverage effectively.

  13. Specular and diffuse object extraction from a LiDAR derived Digital Surface Model (DSM)

    Science.gov (United States)

    Saraf, N. M.; Hamid, J. R. A.; Kamaruddin, M. H.

    2014-02-01

    This paper intents to investigate the indifferent behaviour quantitatively of target objects of interest due to specular and diffuse reflectivity based on generated LiDAR DSM of the study site in Ampang, Kuala Lumpur. The LiDAR data to be used was initially checked for its reliability and accuracy. The point cloud LiDAR data was converted to raster to allow grid analysis of the next process of generating the DSM and DTM. Filtering and masking were made removing the features of interest (i.e. building and tree) and other unwanted above surface features. A normalised DSM and object segmentation approach were conducted on the trees and buildings separately. Error assessment and findings attained were highlighted and documented. The result of LiDAR verification certified that the data is reliable and useable. The RMSE obtained is within the tolerance value of horizontal and vertical accuracy (x, y, z) i.e. 0.159 m, 0.211 m 0.091 m respectively. Building extraction inclusive of roof top based on slope and contour analysis undertaken indicate the capability of the approach while single tree extraction through aspect analysis appears to preserve the accuracy of the extraction accordingly. The paper has evaluated the suitable methods of extracting non-ground features and the effective segmentation of the LiDAR data.

  14. 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.

  15. The Daily Activity Report (DAR) a Novel Measure of Functional Outcome for Serious Mental Illness.

    Science.gov (United States)

    Velligan, Dawn I; Mintz, Jim; Sierra, Cynthia; Martin, Mona L; Fredrick, Megan; Maglinte, Gregory A; Corey-Lisle, Patricia K

    2016-05-01

    The assessment of real-world functional outcomes in clinical trials for medications targeting negative symptoms and cognitive impairment is extremely important. We tested the psychometric properties of the Daily Activity Report (DAR), a novel assessment of productive daily activity. We administered the DAR and additional assessments of functional outcome, functional capacity, cognition and symptomatology to 50 individuals with schizophrenia at 2 time points, 1 month apart and to 25 healthy controls. The DAR records a person's daily activity for 7 consecutive days based upon phone calls made 3 times a day. A total score and scores in 3 domains; instrumental activities (ie, independent living), social and work or school related activities are generated for the DAR. Inter-item consistency was high 0.89-0.94 for each domain and 0.88 overall. Test-retest reliability across 1 month for the total DAR score was 0.67,Psmart phone technology with automatic scoring is the next step. PMID:26712856

  16. 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.

  17. Biotechnologie des archées

    OpenAIRE

    Querellou, Joel

    2010-01-01

    La majorité des enzymes utilisées dans l’industrie provient des bactéries et des levures. Mais les conditions extrêmes dans lesquelles se développent de nombreuses espèces d’archées font que leurs constituants cellulaires possèdent des propriétés et une stabilité propices à leur utilisation en biotechnologie.

  18. Automatic extraction of building boundaries using aerial LiDAR data

    Science.gov (United States)

    Wang, Ruisheng; Hu, Yong; Wu, Huayi; Wang, Jian

    2016-01-01

    Building extraction is one of the main research topics of the photogrammetry community. This paper presents automatic algorithms for building boundary extractions from aerial LiDAR data. First, segmenting height information generated from LiDAR data, the outer boundaries of aboveground objects are expressed as closed chains of oriented edge pixels. Then, building boundaries are distinguished from nonbuilding ones by evaluating their shapes. The candidate building boundaries are reconstructed as rectangles or regular polygons by applying new algorithms, following the hypothesis verification paradigm. These algorithms include constrained searching in Hough space, enhanced Hough transformation, and the sequential linking technique. The experimental results show that the proposed algorithms successfully extract building boundaries at rates of 97%, 85%, and 92% for three LiDAR datasets with varying scene complexities.

  19. [Analysis of an Air Pollution Process Using LiDAR in Nanjing, Spring of 2014].

    Science.gov (United States)

    Bao, Qing; He, Jun-liang; Zha, Yong; Cheng, Feng; Li, Qian-nan

    2015-04-01

    Based on environmental monitoring data, meteorological data and the results of numerical simulation, a typical air pollution process in Nanjing, from 26th May to 1st June, 2014 was deeply analyzed combining aerosol extinction coefficient derived from LiDAR system. Experimental results showed that the entire pollution process was affected by both local pollution and exogenous inputs including dust and smoke. Meteorological factors played a significant role in the generation and elimination of pollutants. Low pressure and temperature inversion also hindered the diffusion of pollutants, while strong rainfall terminated the pollution process. During the pollution, the height of atmospheric boundary layer was lower than normal situation and changed little during the pollution period, which provided a poor diffusion condition for pollutants. LiDAR could accurately detect aerosol vertical structure which was able to capture the temporal and spatial variation of pollutant distributions. Therefore, LiDAR can be of great significance for the atmospheric pollution monitoring. PMID:26164889

  20. Octree-based segmentation for terrestrial LiDAR point cloud data in industrial applications

    Science.gov (United States)

    Su, Yun-Ting; Bethel, James; Hu, Shuowen

    2016-03-01

    Automated and efficient algorithms to perform segmentation of terrestrial LiDAR data is critical for exploitation of 3D point clouds, where the ultimate goal is CAD modeling of the segmented data. In this work, a novel segmentation technique is proposed, starting with octree decomposition to recursively divide the scene into octants or voxels, followed by a novel split and merge framework that uses graph theory and a series of connectivity analyses to intelligently merge components into larger connected components. The connectivity analysis, based on a combination of proximity, orientation, and curvature connectivity criteria, is designed for the segmentation of pipes, vessels, and walls from terrestrial LiDAR data of piping systems at industrial sites, such as oil refineries, chemical plants, and steel mills. The proposed segmentation method is exercised on two terrestrial LiDAR datasets of a steel mill and a chemical plant, demonstrating its ability to correctly reassemble and segregate features of interest.

  1. 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.

  2. 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.

  3. Investigating the spatial distribution of water levels in the Mackenzie Delta using airborne LiDAR

    Science.gov (United States)

    Hopkinson, C.; Crasto, N.; Marsh, P.; Forbes, D.; Lesack, L.

    2011-01-01

    Airborne light detection and ranging (LiDAR) data were used to map water level (WL) and hydraulic gradients (??H/??x) in the Mackenzie Delta. The LiDAR WL data were validated against eight independent hydrometric gauge measurements and demonstrated mean offsets from - 0??22 to + 0??04 m (??LiDAR-based WL gradients could be estimated with confidence over channel lengths exceeding 5-10 km where the WL change exceeded local noise levels in the LiDAR data. For the entire Delta, the LiDAR sample coverage indicated a rate of change in longitudinal gradient (??2H/??x) of 5??5 ?? 10-10 m m-2; therefore offering a potential means to estimate average flood stage hydraulic gradient for areas of the Delta not sampled or monitored. In the Outer Delta, within-channel and terrain gradient measurements all returned a consistent estimate of - 1 ?? 10-5 m m-1, suggesting that this is a typical hydraulic gradient for the downstream end of the Delta. For short reaches ( 0??1 m was observed at a channel constriction entering a meander bend, suggesting a localized modification of the channel hydraulics. Furthermore, water levels in the anabranch channels of the Peel River were almost 1 m higher than in Middle Channel of the Mackenzie River. This suggests: (i) the channels are elevated and have shallower bank heights in this part of the delta, leading to increased cross-delta and along-channel hydraulic gradients; and/or (ii) a proportion of the Peel River flow is lost to Middle Channel due to drainage across the delta through anastamosing channels. This study has demonstrated that airborne LiDAR data contain valuable information describing Arctic river delta water surface and hydraulic attributes that would be challenging to acquire by other means. ?? 2011 John Wiley & Sons, Ltd.

  4. The Use of LiDAR Terrain Data in Characterizing Surface Roughness and Microtopography

    Directory of Open Access Journals (Sweden)

    Kristen M. Brubaker

    2013-01-01

    Full Text Available The availability of light detection and ranging data (LiDAR has resulted in a new era of landscape analysis. For example, improvements in LiDAR data resolution may make it possible to accurately model microtopography over a large geographic area; however, data resolution and processing costs versus resulting accuracy may be too costly. We examined two LiDAR datasets of differing resolutions, a low point density (0.714 points/m2 spacing 1 m DEM available statewide in Pennsylvania and a high point density (10.28 points/m2 spacing 1 m DEM research-grade DEM, and compared the calculated roughness between both resulting DEMs using standard deviation of slope, standard deviation of curvature, a pit fill index, and the difference between a smoothed splined surface and the original DEM. These results were then compared to field-surveyed plots and transects of microterrain. Using both datasets, patterns of roughness were identified, which were associated with different landforms derived from hydrogeomorphic features such as stream channels, gullies, and depressions. Lowland areas tended to have the highest roughness values for all methods, with other areas showing distinctive patterns of roughness values across metrics. However, our results suggest that the high-resolution research-grade LiDAR did not improve roughness modeling in comparison to the coarser statewide LiDAR. We conclude that resolution and initial point density may not be as important as the algorithm and methodology used to generate a LiDAR-derived DEM for roughness modeling purposes.

  5. Sporadic Layer es and Siesmic Activity

    Science.gov (United States)

    Alimov, Obid; Blokhin, Alexandr; Kalashnikova, Tatyana

    2016-07-01

    To determine the influence of seismogenic disturbances on the calm state of the iono-sphere and assess the impact of turbulence development in sporadic-E during earthquake prepa-ration period we calculated the variation in the range of semitransparency ∆fES = f0ES - fbES. The study was based primarily on the ionograms obtained by vertical sounding of the ionosphere at Dushanbe at nighttime station from 15 to 29 August 1986. In this time period four successive earthquakes took place, which serves the purpose of this study of the impact of seis-mogenic processes on the intensity of the continuous generation of ionospheric turbulence. Analysis of the results obtained for seismic-ionospheric effects of 1986 earthquakes at station Dushanbe has shown that disturbance of ionospheric parameters during earthquake prepa-ration period displays a pronounced maximum with a duration of t = 1-6 hours. Ionospheric effects associated with the processes of earthquake preparation emerge quite predictably, which verifies seismogenic disturbances in the ionosphere. During the preparation of strong earthquakes, ionograms of vertical sounding produced at station Dushanbe - near the epicenter area - often shown the phenomenon of spreading traces of sporadic Es. It is assumed that the duration of manifestation of seismic ionospheric precursors in Du-shanbe τ = 1 - 6 hours may be associated with deformation processes in the Earth's crust and var-ious faults, as well as dissimilar properties of the environment of the epicentral area. It has been shown that for earthquakes with 4.5 ≤ M ≤ 5.5 1-2 days prior to the event iono-spheric perturbations in the parameters of the sporadic layer Es and an increase in the value of the range of semitransparency Es - ΔfEs were observed, which could lead to turbulence at altitudes of 100-130 km.

  6. 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。

  7. 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.

  8. Drug-to-antibody ratio (DAR) and drug load distribution by LC-ESI-MS.

    Science.gov (United States)

    Basa, Louisette

    2013-01-01

    This chapter describes an LC-ESI-MS method for the DAR and drug load distribution analysis that is suitable for lysine-linked ADCs. The ADC sample is desalted using a reversed-phase LC column with an acetonitrile gradient prior to online MS analysis. The MS spectrum is processed (deconvoluted) and converted to a series of zero charge state masses that corresponds to the increasing number of drugs in the ADC. Integration of the mass peak area allows the calculation of the DAR and drug load distribution of ADCs. PMID:23913155

  9. Data-Driven Approach to Benthic Cover Type Classification Using Bathymetric LiDAR Waveform Analysis

    OpenAIRE

    Teemu Kumpumäki; Pekka Ruusuvuori; Ville Kangasniemi; Tarmo Lipping

    2015-01-01

    A data-driven method for describing the benthic cover type based on full-waveform bathymetric LiDAR data analysis is presented. The waveform of the bathymetric LiDAR return pulse is first modeled as a sum of three functions: a Gaussian pulse representing the surface return, a function modeling the backscatter and another Gaussian pulse modeling the return from the bottom surface. Two sets of variables are formed: one containing features describing the bottom return and the other describing va...

  10. High-Density LiDAR Mapping of the Ancient City of Mayapán

    OpenAIRE

    Timothy Hare; Marilyn Masson; Bradley Russell

    2014-01-01

    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 ...

  11. MKENO-DAR: a direct angular representation Monte Carlo code for criticality safety analysis

    International Nuclear Information System (INIS)

    Improving the Monte Carlo code MULTI-KENO, the MKENO-DAR (Direct Angular Representation) code has been developed for criticality safety analysis in detail. A function was added to MULTI-KENO for representing anisotropic scattering strictly. With this function, the scattering angle of neutron is determined not by the average scattering angle μ-bar of the Pl Legendre polynomial but by the random work operation using probability distribution function produced with the higher order Legendre polynomials. This code is avilable for the FACOM-M380 computer. This report is a computer code manual for MKENO-DAR. (author)

  12. An Easy-to-Use Airborne LiDAR Data Filtering Method Based on Cloth Simulation

    OpenAIRE

    Wuming Zhang; Jianbo Qi; Peng Wan; Hongtao Wang; Donghui Xie; Xiaoyan Wang; Guangjian Yan

    2016-01-01

    Separating point clouds into ground and non-ground measurements is an essential step to generate digital terrain models (DTMs) from airborne LiDAR (light detection and ranging) data. However, most filtering algorithms need to carefully set up a number of complicated parameters to achieve high accuracy. In this paper, we present a new filtering method which only needs a few easy-to-set integer and Boolean parameters. Within the proposed approach, a LiDAR point cloud is inverted, and then a rig...

  13. Tree species mapping by combining hyperspectral with LiDAR data

    OpenAIRE

    KEMPENEERS Pieter; Vancoillie, Friedl; Liao, Wenzhi; Devriendt, Flore; Vandekerkhove, Kris

    2014-01-01

    This study deals with data fusion of hyperspectral and LiDAR sensors for forest applications. In particular, the added value of different data sources on tree species mapping has been analyzed. A total of seven species have been mapped for a forested area in Belgium: Beech, Ash, Larch, Poplar, Copper beech, Chestnut and Oak. Hyperspectral data is obtained from the APEX sensor in 286 spectral bands. LiDAR data has been acquired with a TopoSys sensor Harrier 56 at full waveform. Confirming previ...

  14. Methods for LiDAR point cloud classification using local neighborhood statistics

    OpenAIRE

    Kim, Angela M.; Olsen, Richard C.; Kruse, Fred A.

    2013-01-01

    The article of record as published may be found at http://dx.doi.org/10.1117/12.2015709 LiDAR data are available in a variety of publicly-accessible forums, providing high-resolution, accurate 3- dimensional information about objects at the Earth’s surface. Automatic extraction of information from LiDAR point clouds, however, remains a challenging problem. The focus of this research is to develop methods for point cloud classification and object detection which can be customized f...

  15. A DATA DRIVEN METHOD FOR BUILDING RECONSTRUCTION FROM LiDAR POINT CLOUDS

    OpenAIRE

    M. Sajadian; H. Arefi

    2014-01-01

    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 extr...

  16. LiDAR Segmentation using Suitable Seed Points for 3D Building Extraction

    OpenAIRE

    S. M. Abdullah; M. Awrangjeb; Lu, G.

    2014-01-01

    Effective building detection and roof reconstruction has an influential demand over the remote sensing research community. In this paper, we present a new automatic LiDAR point cloud segmentation method using suitable seed points for building detection and roof plane extraction. Firstly, the LiDAR point cloud is separated into "ground" and "non-ground" points based on the analysis of DEM with a height threshold. Each of the non-ground point is marked as coplanar or non-coplanar based...

  17. Flood Risk Mapping Using LiDAR for Annapolis Royal, Nova Scotia, Canada

    OpenAIRE

    Tim L. Webster

    2010-01-01

    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 caus...

  18. Deriving pseudo-vertical waveforms from small-footprint full-waveform LiDAR data

    OpenAIRE

    Hermosilla, T.; Coops, Nicholas; Ruiz Fernández, Luis Ángel; Moskal, Monika

    2014-01-01

    This is an author's accepted manuscript of an article published in “Remote Sensing Letters", Volume 5, Issue 4, 2014; copyright Taylor & Francis; available online at: http://www.tandfonline.com/doi/abs/10.1080/2150704X.2014.903350 When processing scanning LiDAR data, it is commonly assumed that the extracted full-waveform LiDAR pulse registers truly vertical information of forest canopies. This assumption may lead to uncertain results for the spatiotemporal analysis of the waveforms due to...

  19. Matemáticas para maestros de primaria: dar sentido al "explicar por qué"

    OpenAIRE

    Beckmann, Sybilla

    2003-01-01

    Para que los maestros desarrollen en sus futuros estudiantes habilidades de razonar y dar sentido a las matemáticas, los mismos maestros deben dar sentido y ser capaces de razonar acerca de las matemáticas que van a enseñar. Sin embargo, muchos de los futuros maestros sólo han vivido las matemáticas como la repetición memorística de procedimientos y no están al tanto de que el razonamiento puede ser usado para resolver problemas de maneras no convencionales, o que el razonamiento está en la b...

  20. Numerical modeling of the airflow around a forest edge using LiDAR-derived forest heigths

    DEFF Research Database (Denmark)

    Boudreault, Louis-Etienne; Dellwik, Ebba; Bechmann, Andreas;

    A 3D methodology to quantify the effect of forests on the mean wind flow field is presented. The methodology is based on the treatment of forest raw data of light detection and ranging (LiDAR) scans, and a computational fluid dynamics (CFD) method based on a Reynolds-averaged Navier-Stokes (Ra......NS) approach using the k−e turbulence model with a corresponding canopy model. The example site investigated is a forest edge located on the Falster island in Denmark, where a measurement campaign was conducted. The LiDAR scans are used in order to obtain the forest heights, which served as input...

  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. LiDAR 安置误差对定位精度影响分析%Influence of LiDAR Systematic Error on Positioning Accuracy

    Institute of Scientific and Technical Information of China (English)

    丁琼; 吕俊涛; 陈高文; 詹晓彬

    2015-01-01

    机载LiDAR为复杂的多传感器集成系统,系统误差是影响LiDAR定位精度的主要误差源。本文基于LiDAR定位方程,模拟往返航飞轨迹和激光脚点数据,定量地引入安置平移和安置旋转误差,研究各个系统误差对定位精度的影响程度和规律。实验结果表明安置平移误差对激光脚点定位精度的影响在对应方向有等量影响,而安置旋转误差对定位精度的影响在对应方向与扫描角相关。%Airborne LiDAR is multi-sensor system.Systematic error is a main error which affects LiDAR positioning accuracy.This paper simulates flight trajectory and laser footprints based on LiDAR positio-ning equation.Boresight errors are introduced to analyze the relationship between LiDAR systematic error and positioning accuracy.Results show that lever arm biases have the same impact on the accuracy of la-ser footprint while boresight angle biases have relationship with scanning angles on the positioning accura-cy.

  3. 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.

  4. LDL-Cholesterin: Wie stark soll es gesenkt werden?

    Directory of Open Access Journals (Sweden)

    Paulweber B

    2002-01-01

    Full Text Available Der klinische Nutzen einer LDL-C-Senkung mittels Statinen wurde in zahlreichen Studien zweifelsfrei nachgewiesen. Die im letzten Jahr veröffentlichten ATP III-Richtlinien stellen eine gute und praxisnahe Hilfestellung für die Entscheidung dar, ob eine Statintherapie eingeleitet und welche Zielwerte angestrebt werden sollen. Die wichtige Frage, ob eine noch aggressivere LDL-C-Senkung zu niedrigeren Zielwerten, als sie in diesen Richtlinien empfohlen werden (unter 80 mg/dl, einen zusätzlichen Nutzen bringt, ist noch nicht beantwortet. Wenn ein solcher Zusatznutzen erzielbar ist, so muß er jedenfalls gegen das möglicherweise erhöhte Nebenwirkungsrisiko einer dazu erforderlichen hochdosierten Statintherapie abgewogen werden. Es ist zu erwarten, daß die Ergebnisse laufender randomisierter Doppelblindstudien zur Klärung dieser Frage in den nächsten Jahren wesentlich beitragen werden. Die kürzlich veröffentlichten Ergebnisse der Heart Protection Study legen den Schluß nahe, daß bei Hochrisikopatienten eine LDL-Senkung im Ausmaß von 30-40 % in jedem Fall erfolgen sollte, auch wenn ein niedriger Ausgangswert des LDL-C vorliegt. Aufgrund von Daten der SAPHIR-Studie (Salzburger Atherosklerose-Präventionsprogramm bei Personen mit hohem Infarkt-Risiko kann abgeschätzt werden, daß gemäß ATP III etwa 20 % der Männer zwischen 40 und 55 Jahren und etwa 8 % der Frauen zwischen 50 und 65 Jahren mit einem Statin behandelt werden sollten. Ein neues hochpotentes Statin (Rosuvastatin, mit dem die empfohlenen Zielwerte noch besser als mit bisher verfügbaren Statinen erreicht werden können, steht kurz vor der Markteinführung. Ezetimibe ist ein Vertreter einer neuen Medikamentenklasse, der selektiven Cholesterinresorptionshemmer. Die Kombination einer niedrigen Statindosis mit Ezetimibe führt zu einer sehr effektiven LDL-C-Senkung, die in derselben Größenordnung liegt, wie sie durch Maximaldosen hochpotenter Statine erzielt werden kann.

  5. SRTM DEM Correction in Vegetated Mountain Areas through the Integration of Spaceborne LiDAR, Airborne LiDAR, and Optical Imagery

    Directory of Open Access Journals (Sweden)

    Yanjun Su

    2015-09-01

    Full Text Available The Shuttle Radar Topography Mission (SRTM digital elevation model (DEM is one of the most complete and frequently used global-scale DEM products in various applications. However, previous studies have shown that the SRTM DEM is systematically higher than the actual land surface in vegetated mountain areas. The objective of this study is to propose a procedure to calibrate the SRTM DEM over large vegetated mountain areas. Firstly, we developed methods to estimate canopy cover from aerial imagery and tree height from multi-source datasets (i.e., field observations, airborne light detection and ranging (LiDAR data, Geoscience Laser Altimeter System (GLAS data, Landsat TM imagery, climate surfaces, and topographic data. Then, the airborne LiDAR derived DEM, covering ~5% of the study area, was used to evaluate the accuracy of the SRTM DEM. Finally, a regression model of the SRTM DEM error depending on tree height, canopy cover, and terrain slope was developed to calibrate the SRTM DEM. Our results show that the proposed procedure can significantly improve the accuracy of the SRTM DEM over vegetated mountain areas. The mean difference between the SRTM DEM and the LiDAR DEM decreased from 12.15 m to −0.82 m, and the standard deviation dropped by 2 m.

  6. Aplicación del Checklist de la OMS para evaluar la preparación ante desastres del Hospital de Cabueñes

    OpenAIRE

    Marinas Vaquero, Noelia

    2012-01-01

    El hospital de cabueñes desarrolla su actividad diaria ante una gran presión asistencial. Una puntual catástrofe podría disminuir su calidad de atención a todos sus habituales usuarios y heridos de una emergencia. El plan de catástrofes que se activaría en el hospital para cubrir todas las necesidades y dar cobertura a los damnificados debe estar bien formulado. Se utilizará el Hospital Emergency Response Checklist de la OMS y la Guía para la elaboración de planes de catástrofes en hospit...

  7. 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...

  8. Semi-Supervised Methods to Identify Individual Crowns of Lowland Tropical Canopy Species Using Imaging Spectroscopy and LiDAR

    Directory of Open Access Journals (Sweden)

    Gregory P. Asner

    2012-08-01

    Full Text Available Our objective is to identify and map individuals of nine tree species in a Hawaiian lowland tropical forest by comparing the performance of a variety of semi-supervised classifiers. A method was adapted to process hyperspectral imagery, LiDAR intensity variables, and LiDAR-derived canopy height and use them to assess the identification accuracy. We found that semi-supervised Support Vector Machine classification using tensor summation kernel was superior to supervised classification, with demonstrable accuracy for at least eight out of nine species, and for all combinations of data types tested. We also found that the combination of hyperspectral imagery and LiDAR data usually improved species classification. Both LiDAR intensity and LiDAR canopy height proved useful for classification of certain species, but the improvements varied depending upon the species in question. Our results pave the way for target-species identification in tropical forests and other ecosystems.

  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. 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.

  11. ULCERA GASTRODUODENAL EM CÃES

    OpenAIRE

    Francisco Assis Uma Costa; Silvaria Maria Medeiros de Sousa Silva; Ana Maria Quessada

    1993-01-01

    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.

  12. LES MACHINES SYNCHRONES AUTOPILOTÉES

    OpenAIRE

    Multon, Bernard

    2010-01-01

    1- GÉNÉRALITES SUR LA MACHINE À COURANT CONTINU ET SUR LA MACHINE SYNCHRONE1.1 - COMPARAISON MACHINE À COURANT CONTINU – MACHINE SYNCHRONE AUTOPILOTÉE1.2 - TYPES DE MACHINE SYNCHRONE ET MODÈLES1.3 - VISION MACROSCOPIQUE DE LA CONVERSION D’ÉNERGIE. CALCUL DU COUPLE ÉLECTROMAGNÉTIQUE MOYEN ET INSTANTANÉ2- LES MACHINES SYNCHRONES AUTOPILOTÉES ALIMENTÉES EN COURANT SINUSOIDAL2.1-DIAGRAMME DE FRESNEL. EXPRESSION DU COUPLE2.2-PRINCIPE D’ALIMENTATION ET DE CONTRÔLE3- LES MACHINES À COURANT CONTINU S...

  13. Point-of-sale promotion of breastmilk substitutes and commercially produced complementary foods in Cambodia, Nepal, Senegal and Tanzania.

    Science.gov (United States)

    Champeny, Mary; Pereira, Catherine; Sweet, Lara; Khin, Mengkheang; Ndiaye Coly, Aminata; Sy Gueye, Ndeye Yaga; Adhikary, Indu; Dhungel, Shrid; Makafu, Cecilia; Zehner, Elizabeth; Huffman, Sandra L

    2016-04-01

    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

  14. Analysis of diverse direct arylation polymerization (DArP) conditions toward the efficient synthesis of polymers converging with stille polymers in organic solar cells

    DEFF Research Database (Denmark)

    Livi, Francesco; Gobalasingham, Nemal S.; Thompson, Barry C.;

    2016-01-01

    Despite the emergence of direct arylation polymerization (DArP) as an alternative method to traditional cross-coupling routes like Stille polymerization, the exploration of DArP polymers in practical applications like polymer solar cells (PSCs) is limited. DArP polymers tend to have a reputation ...

  15. 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

    2012-08-01

    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.

  16. 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...

  17. 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...

  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

    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. 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

  20. Diversity Arrays Technology (DArT) platform for genotyping and mapping in carrot (Daucus carota L.)

    Science.gov (United States)

    Carrot is one of the most important root vegetable crops grown worldwide on more than one million hectares. Its progenitor, wild Daucus carota, is a weed commonly occurring across continents in the temperate climatic zone. Diversity Array Technology (DArT) is a microarray-based molecular marker syst...

  1. 2010 U.S. Geological Survey (USGS) ARRA Topographic LiDAR: Coastal Maine

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — USGS Contract: G10PC00026 Task Order Number: G10PD02143 Task Order Number: G10PD01027 LiDAR was collected at a 2.0 meter nominal post spacing (2.0m GSD) for...

  2. 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

  3. 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....

  4. High-throughput genotyping of hop (Humulus lupulus L.) utilising diversity arrays technology (DArT).

    Science.gov (United States)

    Howard, E L; Whittock, S P; Jakše, J; Carling, J; Matthews, P D; Probasco, G; Henning, J A; Darby, P; Cerenak, A; Javornik, B; Kilian, A; Koutoulis, A

    2011-05-01

    Implementation of molecular methods in hop (Humulus lupulus L.) breeding is dependent on the availability of sizeable numbers of polymorphic markers and a comprehensive understanding of genetic variation. However, use of molecular marker technology is limited due to expense, time inefficiency, laborious methodology and dependence on DNA sequence information. Diversity arrays technology (DArT) is a high-throughput cost-effective method for the discovery of large numbers of quality polymorphic markers without reliance on DNA sequence information. This study is the first to utilise DArT for hop genotyping, identifying 730 polymorphic markers from 92 hop accessions. The marker quality was high and similar to the quality of DArT markers previously generated for other species; although percentage polymorphism and polymorphism information content (PIC) were lower than in previous studies deploying other marker systems in hop. Genetic relationships in hop illustrated by DArT in this study coincide with knowledge generated using alternate methods. Several statistical analyses separated the hop accessions into genetically differentiated North American and European groupings, with hybrids between the two groups clearly distinguishable. Levels of genetic diversity were similar in the North American and European groups, but higher in the hybrid group. The markers produced from this time and cost-efficient genotyping tool will be a valuable resource for numerous applications in hop breeding and genetics studies, such as mapping, marker-assisted selection, genetic identity testing, guidance in the maintenance of genetic diversity and the directed breeding of superior cultivars. PMID:21243330

  5. 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.

  6. Draft Genome Sequence of Bacillus thuringiensis Strain DAR 81934, Which Exhibits Molluscicidal Activity

    OpenAIRE

    Wang, Aisuo; Pattemore, Julie; Ash, Gavin; Williams, Angela; Hane, James

    2013-01-01

    Bacillus thuringiensis has been widely used as a biopesticide for a long time. Its molluscicidal activity, however, is rarely realized. Here, we report the genome sequence of B. thuringiensis strain DAR 81934, a strain with molluscicidal activity against the pest snail Cernuella virgata.

  7. 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.

  8. 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...

  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. A LiDAR method of canopy structure retrieval for wind modeling of heterogeneous forests

    DEFF Research Database (Denmark)

    Boudreault, Louis-Etienne; Bechmann, Andreas; Taryainen, Lasse;

    2015-01-01

    and this information is required for each grid point in the three-dimensional computational domain. By using raw data from aerial LiDAR scans together with the Beer-Lambert law, we propose and test a method to calculate and grid highly variable and realistic frontal area density input. An extensive comparison...

  11. 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...

  12. 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.

  13. a Data Driven Method for Building Reconstruction from LiDAR Point Clouds

    Science.gov (United States)

    Sajadian, M.; Arefi, H.

    2014-10-01

    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.

  14. Processing and accuracy of topobathymetric LiDAR data in land-water transition zones

    OpenAIRE

    Andersen, M.S.; Gergely, A.; Al-Hamdani, Z.; Steinbacher, F.; Larsen, L. R.; Ernstsen, V. B.

    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 ...

  15. 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. The ...

  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. 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

  18. Development of DArT-based PCR markers for selecting drought-tolerant spring barley.

    Science.gov (United States)

    Fiust, Anna; Rapacz, Marcin; Wójcik-Jagła, Magdalena; Tyrka, Mirosław

    2015-08-01

    The tolerance of spring barley (Hordeum vulgare L.) cultivars to spring drought is an important agronomic trait affecting crop yield and quality in Poland. Therefore, breeders require new molecular markers to select plants with lower spring drought susceptibility. With the advent of genomic selection technology, simple molecular tools may still be applicable to screen material for markers of the most important traits and in-depth genome scanning. In previous studies, diversity arrays technology (DArT)-based genetic maps were constructed for F2 populations of Polish fodder and malt barley elite breeding lines, and 15 and 18 quantitative trait loci (QTLs) related to spring drought tolerance were identified, respectively. In this paper, we show the results of a conversion of 30 DArT markers corresponding to 11 QTLs into simple sequence repeat (SSR) and sequence tagged site (STS) markers. Twenty-two polymorphic markers were obtained, including 13 DArT-based SSRs. Additionally, 31 SSR markers, located in close proximity to the DArT markers, were selected from the GrainGenes database and tested. Further analyses of 24 advanced breeding lines with different drought tolerances confirmed that five out of the 30 converted markers, as well as three out of the 31 additional SSR markers, were effective in marker-assisted selection for drought tolerance. The possible function of clones related to these markers in drought tolerance is discussed. PMID:25716655

  19. 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…

  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. 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.

  3. The Effect of Lava Texture on LiDAR Attributes and Full Waveform

    Science.gov (United States)

    Anderson, S. W.; Finnegan, D. C.; LeWinter, A.

    2013-12-01

    The distribution of glassy, vesicular, and crystalline textures on lava flow and dome surfaces provides insights regarding the physical and chemical processes occurring during emplacement. For silicic flows, these textures may reflect variations in the volatile content of lava upon eruption. To assess the efficacy of texture detection with our terrestrial full waveform LiDAR system capable of measuring ~125,000 topographic points/second, we analyzed attribute and full waveform data from a variety of lava textures displayed on recent rhyolitic obsidian flows of the Inyo Dome chain (California) and pahoehoe and aa flows at Kilauea volcano (Hawaii). We find that attributes such as intensity, amplitude and deviation of the returned 1550nm laser pulse fall into discrete ranges associated with glassy, pumiceous and crystalline textures on both the rhyolitic and basaltic surfaces. This enables detection of vesicularity at ranges in excess of 500 m, making LiDAR a useful tool for remotely determining lava texture. Scan times using our Riegl VZ1000 and VZ400 systems require only minutes, allowing for repeated scans over a short time period, and processing times are <1 hour. We have also analyzed the full digitized waveforms of LiDAR pulses returned from these surfaces, and find that they also have unique signatures related to texture. We therefore suggest that LiDAR can provide reliable information on lava texture during eruption, aiding in the interpretation of eruption hazards from increasing volatile contents.

  4. Mapping of post-event earthquake induced landslides in Sg. Mesilou using LiDAR

    Science.gov (United States)

    Hanan Mat Yusoff, Habibah; Azahari Razak, Khamarrul; Yuen, Florence; Harun, Afifi; Talib, Jasmi; Mohamad, Zakaria; Ramli, Zamri; Abd Razab, Razain

    2016-06-01

    Earthquake is a common natural disaster in active tectonic regions. The disaster can induce cascading disasters such as debris flow, mudflow and reactivated old landslides. M 6.0 Ranau earthquake dated on June 05, 2015 coupling with intense and prolonged rainfall caused several mass movements such as debris flow, deep-seated and shallow landslides in Mesilou, Sabah. This study aims at providing a better insight into the use of advanced LiDAR mapping technology for recognizing landslide induced by earthquakes particularly in a vegetated terrain, assessing post event hazard and analyzing its distribution for hazard zonation. We developed the landslide inventory using LiDAR-derived visual analysis method and validated in the field. A landslide inventory map improved with the support of LiDAR derivative data. Finally, landslide inventory was analysed by emphasizing its distribution and density in such a way that it provides clues of risky zone as a result of debris flow. We recommend that mitigation action and risk reduction should be taken place at a transport zone of the channel compared to other zones. This study indicates that modern airborne LiDAR can be a good complementary tool for improving landslide inventory in a complex environment, and an effective tool for rapid regional hazard and risk assessment in the tropics.

  5. 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...

  6. 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.

  7. 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. PMID:25837107

  8. Using satellite and airborne LiDAR to model woodpecker habitat occupancy at the landscape scale.

    Science.gov (United States)

    Vierling, Lee A; Vierling, Kerri T; Adam, Patrick; Hudak, Andrew T

    2013-01-01

    Incorporating vertical vegetation structure into models of animal distributions can improve understanding of the patterns and processes governing habitat selection. LiDAR can provide such structural information, but these data are typically collected via aircraft and thus are limited in spatial extent. Our objective was to explore the utility of satellite-based LiDAR data from the Geoscience Laser Altimeter System (GLAS) relative to airborne-based LiDAR to model the north Idaho breeding distribution of a forest-dependent ecosystem engineer, the Red-naped sapsucker (Sphyrapicus nuchalis). GLAS data occurred within ca. 64 m diameter ellipses spaced a minimum of 172 m apart, and all occupancy analyses were confined to this grain scale. Using a hierarchical approach, we modeled Red-naped sapsucker occupancy as a function of LiDAR metrics derived from both platforms. Occupancy models based on satellite data were weak, possibly because the data within the GLAS ellipse did not fully represent habitat characteristics important for this species. The most important structural variables influencing Red-naped Sapsucker breeding site selection based on airborne LiDAR data included foliage height diversity, the distance between major strata in the canopy vertical profile, and the vegetation density near the ground. These characteristics are consistent with the diversity of foraging activities exhibited by this species. To our knowledge, this study represents the first to examine the utility of satellite-based LiDAR to model animal distributions. The large area of each GLAS ellipse and the non-contiguous nature of GLAS data may pose significant challenges for wildlife distribution modeling; nevertheless these data can provide useful information on ecosystem vertical structure, particularly in areas of gentle terrain. Additional work is thus warranted to utilize LiDAR datasets collected from both airborne and past and future satellite platforms (e.g. GLAS, and the planned IceSAT2

  9. Using satellite and airborne LiDAR to model woodpecker habitat occupancy at the landscape scale.

    Directory of Open Access Journals (Sweden)

    Lee A Vierling

    Full Text Available Incorporating vertical vegetation structure into models of animal distributions can improve understanding of the patterns and processes governing habitat selection. LiDAR can provide such structural information, but these data are typically collected via aircraft and thus are limited in spatial extent. Our objective was to explore the utility of satellite-based LiDAR data from the Geoscience Laser Altimeter System (GLAS relative to airborne-based LiDAR to model the north Idaho breeding distribution of a forest-dependent ecosystem engineer, the Red-naped sapsucker (Sphyrapicus nuchalis. GLAS data occurred within ca. 64 m diameter ellipses spaced a minimum of 172 m apart, and all occupancy analyses were confined to this grain scale. Using a hierarchical approach, we modeled Red-naped sapsucker occupancy as a function of LiDAR metrics derived from both platforms. Occupancy models based on satellite data were weak, possibly because the data within the GLAS ellipse did not fully represent habitat characteristics important for this species. The most important structural variables influencing Red-naped Sapsucker breeding site selection based on airborne LiDAR data included foliage height diversity, the distance between major strata in the canopy vertical profile, and the vegetation density near the ground. These characteristics are consistent with the diversity of foraging activities exhibited by this species. To our knowledge, this study represents the first to examine the utility of satellite-based LiDAR to model animal distributions. The large area of each GLAS ellipse and the non-contiguous nature of GLAS data may pose significant challenges for wildlife distribution modeling; nevertheless these data can provide useful information on ecosystem vertical structure, particularly in areas of gentle terrain. Additional work is thus warranted to utilize LiDAR datasets collected from both airborne and past and future satellite platforms (e.g. GLAS, and

  10. Estimation of Forest Topsoil Properties Using Airborne LiDAR-Derived Intensity and Topographic Factors

    Directory of Open Access Journals (Sweden)

    Chao Li

    2016-07-01

    Full Text Available Forest topsoil supports vegetation growth and contains the majority of soil nutrients that are important indices of soil fertility and quality. Therefore, estimating forest topsoil properties, such as soil organic matter (SOM, total nitrogen (Total N, pH, litter-organic (O-A horizon depth (Depth and available phosphorous (AvaP, is of particular importance for forest development and management. As an emerging technology, light detection and ranging (LiDAR can capture the three-dimensional structure and intensity information of scanned objects, and can generate high resolution digital elevation models (DEM using ground echoes. Moreover, great power for estimating forest topsoil properties is enclosed in the intensity information of ground echoes. However, the intensity has not been well explored for this purpose. In this study, we collected soil samples from 62 plots and the coincident airborne LiDAR data in a Korean pine forest in Northeast China, and assessed the effectiveness of both multi-scale intensity data and LiDAR-derived topographic factors for estimating forest topsoil properties. The results showed that LiDAR-derived variables could be robust predictors of four topsoil properties (SOM, Total N, pH, and Depth, with coefficients of determination (R2 ranging from 0.46 to 0.66. Ground-returned intensity was identified as the most effective predictor for three topsoil properties (SOM, Total N, and Depth with R2 values of 0.17–0.64. Meanwhile, LiDAR-derived topographic factors, except elevation and sediment transport index, had weak explanatory power, with R2 no more than 0.10. These findings suggest that the LiDAR intensity of ground echoes is effective for estimating several topsoil properties in forests with complicated topography and dense canopy cover. Furthermore, combining intensity and multi-scale LiDAR-derived topographic factors, the prediction accuracies (R2 were enhanced by negligible amounts up to 0.40, relative to using

  11. 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

  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. 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. PMID:22033763

  14. LiDAR Segmentation using Suitable Seed Points for 3D Building Extraction

    Science.gov (United States)

    Abdullah, S. M.; Awrangjeb, M.; Lu, G.

    2014-08-01

    Effective building detection and roof reconstruction has an influential demand over the remote sensing research community. In this paper, we present a new automatic LiDAR point cloud segmentation method using suitable seed points for building detection and roof plane extraction. Firstly, the LiDAR point cloud is separated into "ground" and "non-ground" points based on the analysis of DEM with a height threshold. Each of the non-ground point is marked as coplanar or non-coplanar based on a coplanarity analysis. Commencing from the maximum LiDAR point height towards the minimum, all the LiDAR points on each height level are extracted and separated into several groups based on 2D distance. From each group, lines are extracted and a coplanar point which is the nearest to the midpoint of each line is considered as a seed point. This seed point and its neighbouring points are utilised to generate the plane equation. The plane is grown in a region growing fashion until no new points can be added. A robust rule-based tree removal method is applied subsequently to remove planar segments on trees. Four different rules are applied in this method. Finally, the boundary of each object is extracted from the segmented LiDAR point cloud. The method is evaluated with six different data sets consisting hilly and densely vegetated areas. The experimental results indicate that the proposed method offers a high building detection and roof plane extraction rates while compared to a recently proposed method.

  15. 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.

  16. 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.

  17. Estimating Above Ground Biomass using LiDAR in the Northcoast Redwood Forests

    Science.gov (United States)

    Rao, M.; Stewart, E.

    2010-12-01

    In recent years, LiDAR (Light Intensity Detection Amplification and Ranging) is increasingly being used in estimating biophysical parameters related to forested environments. The main goal of the project is to estimate long-term biomass accumulation and carbon sequestration potential of the redwoods ecosystem. The project objectives are aimed at providing an assessment of carbon pools within the redwood ecosystem. Specifically, we intend to develop a relational model based on LiDAR-based canopy estimates and extensive ground-based measurements available for the old-growth redwood forest located within the Prairie Creek Redwoods State Park, CA. Our preliminary analysis involved developing a geospatial database, including LiDAR data collected in 2007 for the study site, and analyzing the data using USFS Fusion software. The study area comprised of a 12-acres section of coastal redwood (Sequoia sempervirens) in the Prairie Creek Redwoods State Park, located in Orick, CA. A series of analytical steps were executed using the USFS FUSION software to produce some intermediate data such as bare earth model, canopy height model, canopy coverage model, and canopy maxima treelist. Canopy maxima tree tops were compared to ground layer to determine height of tree tops. A total of over 1000 trees were estimated, and then with thinning (to eliminate errors due to low vegetation > 3 meters tall), a total of 950 trees were delineated. Ground measurements were imported as a point based shapefile and then compared to the treetop heights created from LiDAR data to the actual ground referenced data. The results were promising as most estimated treetops were within 1-3 meters of the ground measurements and generally within 3-5m of the actual tree height. Finally, we are in the process of applying some allometric equations to estimate above ground biomass using some of the LiDAR-derived canopy metrics.

  18. Age at Menarche in Schoolgirls from Tanzania in Light of Socioeconomic and Sociodemographic Conditioning

    OpenAIRE

    Rebacz, Ewa

    2009-01-01

    The goal of this study is to determine the age at menarche of girls from Tanzania examined in 2005 considering their families’ social and material status. For the purpose of the analysis of the age at menarche, N=71 girls were qualified (N=8 from Dar es Salaam and N=63 from Mafinga) out of N=98 who took part in the anthropological study. The calendar age of the girls who qualified for the determination of the age at menarche ranged from 12.9 to 22.7 years of age (X=15.9 ± 1.9). The age at men...

  19. 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...

  20. Scaling up postabortion contraceptive service--results from a study conducted among women having unwanted pregnancies in urban and rural Tanzania

    DEFF Research Database (Denmark)

    Rasch, Vibeke; Yambesi, Fortunata; Kipingili, Rose

    2005-01-01

    and rural Tanzania and evaluates the outcome of a postabortion care intervention. METHODS: Data were collected among 781 women admitted with incomplete abortion in Dar es Salaam region (urban Tanzania) and 575 women in Kagera region (rural Tanzania). RESULTS: Sixty-seven percent of the women in urban...... Tanzania and 42% in rural Tanzania stated that their pregnancy was unwanted. Contraceptive acceptance among women with unwanted pregnancies was high; 93% in urban Tanzania and 71% in rural Tanzania left with a contraceptive method. CONCLUSION: The high proportion of women with unwanted pregnancies in urban...... and rural Tanzania underlines the need of scaling up postabortion contraceptive service....