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    Structured hydrological analysis for targeting fallow evaporation to improve water productivity at the irrigation system level

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    International audienceThis paper provides results of an application of a holistic systematic approach of water accounting using remote sensing and GIS coupled with ground water modeling to evaluate water saving options by tracking non-beneficial evaporation in the Liuyuankou Irrigation System (LIS) of China. Groundwater rise is a major issue in the LIS, where groundwater levels have risen alarmingly close to the ground surface (within 1 m) near the Yellow River. The lumped water balance analysis showed high fallow evaporation losses and which need to be reduced for improving water productivity. The seasonal actual evapotranspiration (ETs) was estimated by applying the SEBAL algorithm for eighteen NOAA AVHRR-12 images over the year of 1990?1991. This analysis was aided by the unsupervised land use classification applied to two Landsat 5 TM images of the study area. SEBAL results confirmed that a significant amount (116.7 MCM) of water can be saved by reducing ETs from fallow land which will result in improved water productivity at the irrigation system. The water accounting indicator (for the analysis period) shows that the process fraction per unit of depleted water (PFdepleted) is 0.52 for LIS, meaning that 52% of the depleted water is consumed by agricultural crops and 48% is lost through non-process depletion. Finally, the groundwater modeling was applied to simulate three land use and water management interventions to assess their effectiveness for both water savings and impact on the groundwater in LIS. MODFLOW's Zone Budget code calculates the groundwater budget of user-specified subregions, the exchange of flows between subregions and also calculates a volumetric water budget for the entire model at the end of each time step. The simulation results showed that fallow evaporation could be reduced between 14.2% (25.51 MCM) and 45.3% (81.36 MCM) by interventions such as canal lining and ground water pumping. The reduction in non-beneficial ETs volumes would mean that more water would be available for other uses and it would allow the introduction of more surface water supplies in the area through improved water management strategies. This will ultimately lead to improved water productivity of the LIS system

    Study on low-grade galena-barite ore beneficiation in Khuzdar, Balochistan, Pakistan

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    Purpose. Galena and barite are the principal minerals of lead and barium respectively. Both minerals are used extensively in industries because of their distinct properties. In complex poly metallic ores, it is always desirable to produce separate mineral concentrates for subsequent metal extraction. Separation of two or more minerals from complex low-grade multi-metallic ore into commercial grade concentrates requires suitable process. Methods. This research work is centered on development a suitable process for the beneficiation of a low-grade galena-barite ore originating from Khuzdar region (Balochistan Province, Pakistan). Findings. The low-grade ore assaying 39.90% Pb and 24.64% BaSO4 was beneficiated on bench-scale by sequential froth flotation process to recover valuable galena and barite concentrates. The important variables of froth flotation process such as feed size, pulp pH, pulp density, impeller speed, type and quantities of flotation reagents, pulp conditioning time and froth collecting time were optimized to achieve maximum recovery and grade of both concentrates. The rougher galena and barite concentrates were re-ground separately and subjected to one cleaning flotation to obtain better grade final concentrates of respective minerals. Originality. A process flow-sheet was designed in the light of this study. Practical implications. Froth flotation experiments showed that a galena concentrate containing 77.38% Pb with recovery of 90.64% and a barite concentrate assaying 90.23% BaSO4 with recovery of 80.16% could be recovered from this ore. Both the concentrates fall in the category of metallurgical and chemical grades and are suitable for industrial applications.Мета. Підвищення якості низькосортної галеніт-баритової руди, знайденої в Хуздарском районі провінції Белуджистан (Пакистан), до концентрату металургійного якості, що містить більше 70% Pb, із використанням методу пінної флотації. Методика. Масова проба галеніт-баритової руди вагою близько 100 кг була відібрана з шахти Мал-Хор на північному заході від Хуздару та доставлена в лабораторію переробки мінералів MPRC, PCSIR Lahore для проведення досліджень. Зразок підданий первинному подрібненню із використанням щокової дробарки з наступним вторинним подрібненням із використанням валкової дробарки. Зразок до і після флотації піддавався комплексному хімічному і рентгеноструктурному аналізу (XRD). Флотаційні випробування проводилися на лабораторній флотаційній машині D-12. Після визначення оптимального помелу були проведені випробування для оптимізації щільності пульпи, рН пульпи, швидкості перемішування, кількості доданих реагентів, часу флотації й часу кондиціонування. Результати. Встановлено, що вміст свинцю та барію в поліметалічній руді є достатнім для промислового використання. Отримано оптимальну ступінь подрібнення і відновлення при розмірі подачі 80% мінус 200 меш. Виявлено, що збільшення щільності пульпи дещо знижується при збільшенні В/Т з 20 до 35%, але відновлення збільшується, а максимальне відновлення досягнуто при 30%. При використанні для коригування рН пульпи етілксантата калію, а потім бариту з олеатом натрію, виявлено, що при постійних умовах розміру часток і співвідношення твердої речовини та рідини максимально повторне покриття галену досягається при рН 8.5 і бариту при рН 10.0. Було відзначено, що невелика зміна pH значно змінила ступінь і відновлення. Розкрито вплив швидкості перемішування робочого колеса й відзначено, що оптимальною швидкістю на грубій стадії є швидкість 1100 об/хв, а на стадії очищення – 1000 об/хв. Доведено, що методом пінної флотації з даної руди можна отримати концентрат галеніту із вмістом 77.38% Pb і ступенем відновлення 90.64%, а також концентрат бариту із вмістом 90.23% BaSO4 і ступенем відновлення 80.16%. Наукова новизна. Встановлено характер впливу специфічних речовин, що поліпшують показники про-процесу флотації, які сприяють якісному відділенню цінних компонентів руди від порожніх домішок. Практична значимість. Розроблено принципову схему процесу збагачення галеніт-баритової руди на основі пінної флотації в замкнутому циклі. Отримані концентрати галеніту й бариту відповідають необхідним металургійним і хімічним стандартам та можуть знайти промислове застосування.Цель. Повышение качества низкосортной галенит-баритовой руды, найденной в Хуздарском районе провинции Белуджистан (Пакистан), до концентрата металлургического качества, содержащего более 70% Pb, с использованием метода пенной флотации. Методика. Массовая проба галенит-баритовой руды весом около 100 кг была отобрана из шахты Мал-Хор к северо-западу от Хуздара и доставлена в лабораторию переработки минералов MPRC, PCSIR Lahore для проведения исследований. Образец подвергнут первичному дроблению с использованием щековой дробилки, с последующим вторичным дроблением с использованием валковой дробилки. Образец до и после флотации подвергался комплексному химическому и рентгеноструктурному анализу (XRD). Флотационные испытания проводились на лабораторной флотационной машине D-12. После определения оптимального помола были проведены испытания для оптимизации плотности пульпы, рН пульпы, скорости перемешивания, количества добавленных реагентов, времени флотации и времени кондиционирования. Результаты. Установлено, что содержание свинца и бария в полиметаллической руде является достаточным для промышленного использования. Получена оптимальная степень измельчения и восстановления при размере подачи 80% минус 200 меш. Выявлено, что увеличение плотности пульпы несколько снижается при увеличении В/Т с 20 до 35%, но восстановление увеличилось, а максимальное восстановление достигнуто при 30%. При использовании для корректировки рН пульпы этилксантата калия, а затем барита с олеатом натрия, обнаружено, что при постоянных условиях размера частиц и соотношения твердого вещества и жидкости максимальное повторное покрытие галена достигается при рН 8.5 и барита при рН 10.0. Было отмечено, что небольшое изменение pH значительно изменило степень и восстановление. Раскрыто влияние скорости перемешивания рабочего колеса и отмечено, что оптимальной скоростью на грубой стадии является скорость 1100 об/мин, а на стадии очистки – 1000 об/мин. Доказано, что методом пенной флотации из данной руды можно получить концентрат галенита с содержанием 77.38% Pb и степенью восстановления 90.64%, а также концентрат барита с содержанием 90.23% BaSO4 и степенью восстановления 80.16%. Научная новизна. Установлен характер влияния специфических веществ, улучшающих показатели процесса флотации, что способствовало качественному отделению ценных компонентов руды от пустых примесей. Практическая значимость. Разработана принципиальная схема процесса обогащения галенит-баритовой руды на основе пенной флотации в замкнутом цикле. Полученные концентраты галенита и барита соответствуют металлургическим и химическим стандартам и могут найти промышленное применение.The authors are grateful to Associate Professor, Dr. Zulifqar Ali, Department of Mining Engineering, University of Engineering and Technology (UET), Lahore for his valuable support/ cooperation in X-ray diffraction (XRD) analysis and mineralogical evaluation of ore

    The concept of district health management in Malaysia

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    Background: In Malaysia, public health services sector are administered by the Ministry of Health through its central headquarters to the state and district offices. The District Health Offices particularly manage and coordinate the delivery of an effective, efficient and affordable health services in the districts throughout Malaysia. Materials and Methods: The information and statistics used in this article are based on the data collected from reports, articles, and publications by the Ministry of Health Malaysia and journals published pertaining to the District Health Management in Malaysia. Result: A District Health Office is entrusted with two major roles; to deliver public health services and to manage resources within a district. Led by a Public Health Physician, it acts as a body to oversee the execution of the national health policies and strategies at the ground level and serves to enforce existing health related legislation. It is also responsible in disease monitoring and surveillance and also the achievement of specific health indicators for each activity. There are six major services provided by the District Health Office, namely the Family Health, Disease Control, Occupational Health, Food Quality Control, Health Education, as well as Environmental Health and Water Supply Services. Conclusion: A District Health Office functions as the basic operational level in Malaysia healthcare system. Being the backbone in government healthcare system, it is essential to provide a well organised and integrated health service in delivering quality healthcare services to the population

    17th International Congress on Modelling and Simulation (MODSIM07)

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    This paper presents the situation analysis of a re-use system of return flow for irrigation in District 1 of the Upper Pumpanga River Integrated Irrigation System (UPRIIS), Philippines. While elaborating the situation analysis, emphasis is given to quantification of water re-use and its related economic benefits under gravity-fed irrigation systems. This irrigation system presents a distinct geophysical feature which provides opportunities for capturing irrigation outflows from rice fields of upstream areas through a network of natural creeks. These creeks feed into check dams which divert irrigation supplies for downstream areas. In UPRIIS area, the major sources of re-use system include groundwater pumping, lifting surface water from creeks and irrigation supplies from check dams. Specifically, this study aimed to: a) quantify the current level of water re-use from creeks, groundwater and check dams; and b) to estimate the economic benefits of water re-use from pumping groundwater and creeks in District 1 of UPRIIS. This study was conducted during the dry season of 2001, (19 November 2000 - 18 May 2001). During this period, the average rainfall was only 190mm (long term average of 170 mm). A comprehensive survey was carried out in District 1 with the help of the National Irrigation Administration (NIA). This survey focused on obtaining information regarding pumping technologies, sources of re-use water (groundwater or creek), existing cropping patterns and pumped water sharing practices. An additional 50 pump owners, from a total of 1154 pumps, were selected for detailed investigation and monitoring of total water with drawl from different sources of water. The geographic information system (GIS) was developed to characterize the study area. To quantify the amount of water re-use, pumps were calibrated 7-9 times with a V-notch weir to determine the actual discharge for different sizes of pump. The total amount of water being pumped by each monitored farm was determined by multiplying the actual discharge with the total pumping times/hectare. Water and yield relations were determined by developing production functions, and economic benefits were determined by estimating the water productivity (economics) and calculating the marginal value of water. In the study area, it was found that 22% of the farmers use pumps to draw water from shallow tube wells for supplementary irrigation. The pump density ranged from 0.13-0.2 pumps/ha, showing that the majority of the farmers depend on groundwater. The estimated total volume pumped per ha ranged from 0.39-6.93 m3/ha during the dry season. Overall, this is equivalent to 30% of the water lost through seasonal actual evapotranspiration from the rice crop. There was no difference in pumping cost between the creek (0.012 /m3)andshallowpumps(0.012/m3) and shallow pumps (0.012 /m3). Overall marginal value product (MVP) of water re-use was 0.0406 /m3.TheMVPofwaterreusefromcreek(0.0438/m3. The MVP of water re-use from creek (0.0438 /m3) was slightly higher than the water re-use through the pumping ground water (0.0388 $/m3). The results showed that water re-use plays a dominant role in the growth of a rice crop during the dry season. The results clearly indicate that the quantification of volumes of water re-use is crucial for understanding and finding real water saving possibilities at the irrigation system level. The results also revealed that rice production systems are still profitable despite high pumping costs and other associated expenses in District 1. These findings would lead to an improvement in the water use efficiency and water productivity of irrigated rice systems

    Low cost three-dimensional virtual model construction for remanufacturing industry

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    Remanufactured products can save up to 80% of production and energy costs whilst generating lower CO2 emissions. The key success factors for remanufacturing are quality, lead-time and cost. Extensive work within the industry and the detailed analysis of the remanufacturing process has shown that component inspection has significant bearing on overall productivity. Currently, the remanufacturing process is performed manually. Automation of remanufacturing process will not only decrease the number of non-remanufacturable components, through decreasing cost and introduce increasing consistency in quality, but also attract industries to design for remanufacture. In current work an automotive engine (in as received condition) is 3D reconstructed virtually, using the Visual Structure for Motion (VSFM) technique. These initial experiments assess the feasibility of using Videogrammetry to acquire pre-disassembly 3D model of the engine. Multiple 2D images were acquired and processed to find matching common features. The location of the camera was calculated through the matching features, producing a three-dimensional digital representation of the captured volume. A sparse point cloud was initially created which and was then converted into a dense 3D point cloud. The 3D point cloud was converted into a meshed model. 2D images are stitched together to create a virtual model of the engine with surface texture and colour. Small features of a few couple of millimetres in size are clearly visible in the 3D model

    Enhanced Vitreous Imaging in Healthy Eyes Using Swept Source Optical Coherence Tomography

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    Purpose To describe enhanced vitreous imaging for visualization of anatomic features and microstructures within the posterior vitreous and vitreoretinal interface in healthy eyes using swept-source optical coherence tomography (SS-OCT). The study hypothesis was that long-wavelength, high-speed, volumetric SS-OCT with software registration motion correction and vitreous window display or high-dynamic-range (HDR) display improves detection sensitivity of posterior vitreous and vitreoretinal features compared to standard OCT logarithmic scale display. Design Observational prospective cross-sectional study. Methods Multiple wide-field three-dimensional SS-OCT scans (500×500A-scans over 12×12 mm2) were obtained using a prototype instrument in 22 eyes of 22 healthy volunteers. A registration motion-correction algorithm was applied to compensate motion and generate a single volumetric dataset. Each volumetric dataset was displayed in three forms: (1) standard logarithmic scale display, enhanced vitreous imaging using (2) vitreous window display and (3) HDR display. Each dataset was reviewed independently by three readers to identify features of the posterior vitreous and vitreoretinal interface. Detection sensitivities for these features were measured for each display method. Results Features observed included the bursa premacularis (BPM), area of Martegiani, Cloquet's/BPM septum, Bergmeister papilla, posterior cortical vitreous (hyaloid) detachment, papillomacular hyaloid detachment, hyaloid attachment to retinal vessel(s), and granular opacities within vitreous cortex, Cloquet's canal, and BPM. The detection sensitivity for these features was 75.0% (95%CI: 67.8%–81.1%) using standard logarithmic scale display, 80.6% (95%CI: 73.8%–86.0%) using HDR display, and 91.9% (95%CI: 86.6%–95.2%) using vitreous window display. Conclusions SS-OCT provides non-invasive, volumetric and measurable in vivo visualization of the anatomic microstructural features of the posterior vitreous and vitreoretinal interface. The vitreous window display provides the highest sensitivity for posterior vitreous and vitreoretinal interface analysis when compared to HDR and standard OCT logarithmic scale display. Enhanced vitreous imaging with SS-OCT may help assess the natural history and treatment response in vitreoretinal interface diseases.Massachusetts Lions Eye Research Fund, Inc.Research to Prevent Blindness, Inc. (United States)United States. Air Force Office of Scientific Research (grant FA9550-1010551)United States. Air Force Office of Scientific Research (grant FA9550-12-1-0499)German Research Foundation (DFG-HO-1791/11-1)German Research Foundation (DFGGSC80-SAOT)German Research Foundation (DFG Research Training Group 1773)Champalimaud Foundation (Champalimaud Vision Award Fund)National Institutes of Health (U.S.) (R01- EY11289-28)National Institutes of Health (U.S.) (R01-CA075289-16)National Institutes of Health (U.S.) (R44-EY022864-01

    Fuel Production Using Membrane Reactors

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    The constant increase in population has led to greater fossil fuel consumption, and subsequently a significant increase in greenhouse gases emission to the atmosphere. This presents a serious threat to the environment and impacts climate change to a great extent. Fossil fuel supplies are depleting fast, and the price of these fuels is also increasing due to their heightened demand. The environmental concerns regarding this are the increased emissions of harmful pollutants such as carbon dioxide, sulphur dioxide and hydrocarbons. Here we review the alternative fuel technologies which are currently employed to aid the eradication of the current environmental problems. Most notably, this review will demonstrate how membrane reactors are implemented to improve and intensify the existing renewable fuel production processes. Furthermore, the advantages of membrane reactors when compared to the conventional ones, will be discussed; and the environmental benefits these particular reactors pose will also be highlighted. We will showcase how these membrane reactors have been applied successfully to improve biodiesel, hydrogen and Fischer-Tropsch synthesis processes. The application of membranes aids the increase in the conversion of desired products, whilst shifting the equilibrium of the reaction and reducing undesired by-products. Membrane reactors also overcome immiscibility issues that hinder conventional reactor processes. Moreover, they have also demonstrated a significant reduction in the separation and purification of impurities, as they couple them both in one step. This shows drastic economic and energy requirement reductions in the amount of wastewater treatment associated with conventional fuel production reactor
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