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Zhao, Yan, Yuki Endo, Yoshihiro Kanamori, and Jun Mitani. "Approximating 3D surfaces using generalized waterbomb tessellations." Journal of Computational Design and Engineering 5, no. 4 (January 9, 2018): 442–48. http://dx.doi.org/10.1016/j.jcde.2018.01.002.
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Abstract Origami has received much attention in geometry, mathematics, and engineering due to its potential to construct 3D developable shapes from designed crease patterns on a flat sheet. Waterbomb tessellation, which is one type of traditional origami consisting of a set of waterbomb bases, has been used to create geometrically appealing 3D shapes and been widely studied. In this paper, we propose a method for approximating target surfaces, which are parametric surfaces of varying or constant curvatures, using generalized waterbomb tessellations. First, we generate a base mesh by tiling the target surface using waterbomb bases. Then, by applying a simple numerical optimization algorithm to the base mesh, we achieve a developable waterbomb tessellation, which can be developed onto a plane without stretching. We provide a prototype system using which the user can adjust the resolution of the tessellation and modify waterbomb bases. Our work could expand the exploration of building developable 3D structures using origami. Highlights Generalizing waterbomb tessellations to fit target 3D parametric surfaces. Achieving developable tessellations by a simple numerical optimization algorithm. Non-axisymmetric or non-orientable resulting approximations are demonstrated.
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Hanna, Brandon H., Jason M. Lund, Robert J. Lang, Spencer P. Magleby, and Larry L. Howell. "Waterbomb base: a symmetric single-vertex bistable origami mechanism." Smart Materials and Structures 23, no. 9 (August 11, 2014): 094009. http://dx.doi.org/10.1088/0964-1726/23/9/094009.
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Han, Hesheng, Lihua Tang, Dengqing Cao, and Lun Liu. "Modeling and analysis of dynamic characteristics of multi-stable waterbomb origami base." Nonlinear Dynamics 102, no. 4 (November 23, 2020): 2339–62. http://dx.doi.org/10.1007/s11071-020-06082-8.
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Siver, Peter A., Jeffry M. Pelczar, Anne Marie Lott, and Andrzej Pisera. "The Giraffe Pipe database project: A web-based database for siliceous microfossils from a freshwater Eocene waterbody." Nova Hedwigia, Beihefte 136 (June 24, 2010): 325–31. http://dx.doi.org/10.1127/1438-9134/2010/0136-0325.
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Fujisada, Hiroyuki, Minoru Urai, and Akira Iwasaki. "Technical Methodology for ASTER Global Water Body Data Base." Remote Sensing 10, no. 12 (November 22, 2018): 1860. http://dx.doi.org/10.3390/rs10121860.
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A waterbody detection technique is an essential part of a digital elevation model (DEM) generation to delineate land–water boundaries and set flattened elevations. This paper describes the technical methodology for improving the initial tile-based waterbody data that are created during production of the Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) GDEM, because without improvement such tile-based waterbodies data are not suitable for incorporating into the new ASTER GDEM Version 3. Waterbodies are classified into three categories: sea, lake, and river. For sea-waterbodies, the effect of sea ice is removed to better delineate sea shorelines in high latitude areas: sea ice prevents accurate delineation of sea shorelines. For lake-waterbodies, the major part of the processing is to set the unique elevation value for each lake using a mosaic image that covers the entire lake area. Rivers present a unique challenge, because their elevations gradually step down from upstream to downstream. Initially, visual inspection is required to separate rivers from lakes. A stepwise elevation assignment, with a step of one meter, is carried out by manual or automated methods, depending on the situation. The ASTER global water database (GWBD) product consists of a global set of 1° latitude-by-1° longitude tiles containing water body attribute and elevation data files in geographic latitude and longitude coordinates and with one arc second posting. Each tile contains 3601-by-3601 data points. All improved waterbody elevation data are incorporated into the ASTER GDEM to reflect the improved results.
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Makinde, Esther Oluwafunmilayo, Ayobami Taofeek Salami, James Bolarinwa Olaleye, and Oluwapelumi Comfort Okewusi. "Object Based and Pixel Based Classification Using Rapideye Satellite Imager of ETI-OSA, Lagos, Nigeria." Geoinformatics FCE CTU 15, no. 2 (December 8, 2016): 59–70. http://dx.doi.org/10.14311/gi.15.2.5.
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Several studies have been carried out to find an appropriate method to classify the remote sensing data. Traditional classification approaches are all pixel-based, and do not utilize the spatial information within an object which is an important source of information to image classification. Thus, this study compared the pixel based and object based classification algorithms using RapidEye satellite image of Eti-Osa LGA, Lagos. In the object-oriented approach, the image was segmented to homogenous area by suitable parameters such as scale parameter, compactness, shape etc. Classification based on segments was done by a nearest neighbour classifier. In the pixel-based classification, the spectral angle mapper was used to classify the images. The user accuracy for each class using object based classification were 98.31% for waterbody, 92.31% for vegetation, 86.67% for bare soil and 90.57% for Built up while the user accuracy for the pixel based classification were 98.28% for waterbody, 84.06% for Vegetation 86.36% and 79.41% for Built up. These classification techniques were subjected to accuracy assessment and the overall accuracy of the Object based classification was 94.47%, while that of Pixel based classification yielded 86.64%. The result of classification and accuracy assessment show that the object-based approach gave more accurate and satisfying results
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Ampim, Peter A. Y., Michael Ogbe, Eric Obeng, Edwin K. Akley, and Dilys S. MacCarthy. "Land Cover Changes in Ghana over the Past 24 Years." Sustainability 13, no. 9 (April 28, 2021): 4951. http://dx.doi.org/10.3390/su13094951.
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Changes in land cover (LC) can lead to environmental challenges, but few studies have investigated LC changes at a country wide scale in Ghana. Tracking LC changes at such a scale overtime is relevant for devising solutions to emerging issues. This study examined LC changes in Ghana for the past almost two and half decades covering 1995–2019 to highlight significant changes and opportunities for sustainable development. The study used land cover data for six selected years (1995, 2000, 2005, 2010, 2015, and 2019) obtained from the European Space Agency. The data was analyzed using R, ArcGIS Pro and Microsoft Excel 365 ProPlus. The original data was reclassified into eight LC categories, namely: agriculture, bare area, built-up, forest, grassland, other vegetation, waterbody, and wetland. On average, the results revealed 0.7%, 131.7%, 23.3%, 46.9%, and 11.2% increases for agriculture, built-up, forest, waterbody, and wetland, respectively, across the nation. However, losses were observed for bare area (92.8%), grassland (51.1%), and other vegetation (41%) LCs overall. Notably, agricultural land use increased up to 2015 and decreased subsequently but this did not affect production of the major staple foods. These findings reveal the importance of LC monitoring and the need for strategic efforts to address the causes of undesirable change.
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Dundas, Shannon J., Molly Vardanega, Patrick O’Brien, and Steven R. McLeod. "Quantifying Waterfowl Numbers: Comparison of Drone and Ground-Based Survey Methods for Surveying Waterfowl on Artificial Waterbodies." Drones 5, no. 1 (January 13, 2021): 5. http://dx.doi.org/10.3390/drones5010005.
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Drones are becoming a common method for surveying wildlife as they offer an aerial perspective of the landscape. For waterbirds in particular, drones can overcome challenges associated with surveying locations not accessible on foot. With the rapid uptake of drone technology for bird surveys, there is a need to compare and calibrate new technologies with existing survey methods. We compared waterfowl counts derived from ground- and drone-based survey methods. We sought to determine if group size and waterbody size influenced the difference between counts of non-nesting waterfowl and if detection of species varied between survey methods. Surveys of waterfowl were carried out at constructed irrigation dams and wastewater treatment ponds throughout the Riverina region of New South Wales (NSW), Australia. Data were analyzed using Bayesian multilevel models (BMLM) with weakly informative priors. Overall, drone-derived counts of waterfowl were greater (+36%) than ground counts using a spotting scope (β_ground= 0.64 [0.62–0.66], (R2 = 0.973)). Ground counts also tended to underestimate the size of groups. Waterbody size had an effect on comparative counts, with ground counts being proportionally less than drone counts (mean = 0.74). The number of species identified in each waterbody type was similar regardless of survey method. Drone-derived counts are more accurate compared to traditional ground counts, but drones do have some drawbacks including initial equipment costs and time-consuming image or photo processing. Future surveys should consider using drones for more accurately surveying waterbirds, especially when large groups of birds are present on larger waterbodies.
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Meng, Lingkui, Xiaobing Wei, Miao Yang, Yizhuo Meng, Yang Chen, Jianguo Cheng, and Wen Zhang. "A detection method for reservoir waterbodies vector data based on EGADS." Open Geosciences 12, no. 1 (December 13, 2020): 1589–602. http://dx.doi.org/10.1515/geo-2020-0205.
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AbstractOwing to the effects of camera, illumination, extraction algorithm defect, and other reasons, vector data for reservoir waterbodies extracted from remote sensing data may have quality issues, impacting the efficiency of data utilization in areas such as water resource management and reservoir monitoring. To efficiently detect abnormal data from massive vector products of reservoir waterbodies, a semi-automatic detection method for reservoir waterbody vector data is presented. The method has three phases. First, the original reservoir vector data are preprocessed to obtain the time series of the area of reservoir waterbodies. Second, data modeling with time series of reservoir waterbodies area data is done using the extensible generic anomaly detection system (EGADS) plug-in framework and time series modeling is conducted using the Olympic model. Third, data that have quality problems are identified with K\sigma model was used to determine the outliers; thereby, the date of the outliers is detected. Results of accuracy verification show that the sensitivity and specificity of the method were 94.44 and 83.87%, respectively, showing its feasibility for use in anomaly detection in polygonal reservoir waterbody vector data with far greater efficiency than traditional manual inspection.
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Wu Decao, 吴德操, 魏. 彪. Wei Biao, 汤. 戈. Tang Ge, 冯. 鹏. Feng Peng, 唐. 媛. Tang Yuan, 刘. 娟. Liu Juan, and 熊双飞 Xiong Shuangfei. "Turbidity Disturbance Compensation for UV-VIS Spectrum of Waterbody Based on Mie Scattering." Acta Optica Sinica 37, no. 2 (2017): 0230007. http://dx.doi.org/10.3788/aos201737.0230007.
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Yue, Hui, and Ying Liu. "Method for delineating open water bodies based on the deeply clear waterbody delineation index." Journal of Applied Remote Sensing 13, no. 03 (August 24, 2019): 1. http://dx.doi.org/10.1117/1.jrs.13.038504.
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Tobore, Anthony, Bolarinwa Senjobi, Temitope Ogundiyi, and Samuel Bamidele. "Geospatial assessment of wetland soils for rice production in Ajibode using geospatial techniques." Open Geosciences 13, no. 1 (January 1, 2021): 310–20. http://dx.doi.org/10.1515/geo-2020-0227.
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Abstract Wetlands played an important role in human development and nature nutrient store for rice cultivation. Spatial techniques have gained importance in monitoring wetland changes. The study aimed to assess wetland soils for rice production using spatial techniques. The area was sample using stratified grid sampling. Nutrient availability and rice suitability were assessed in ArcGIS 10.6 environment. The soil was characterized into Eutric fluvaquent (Soil Survey Staff, 2010) and correlated as fluvisols in the World Reference Base system. The results of the land cover changes showed that built-up, waterbody, and farmland have increased by 39, 18, and 29%, respectively, and 13% decrease was observed in vegetation. The study concluded that soils of the studied area varied from marginally (75%), not suitable (20%), and permanently not suitable (5%) for rice production. Therefore, without proper assessment and management of these studied soils, rice production will continue to be futile.
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Zhao, Xin, Ping Wang, Chao Chen, Tao Jiang, Zhigang Yu, and Biyun Guo. "Waterbody information extraction from remote-sensing images after disasters based on spectral information and characteristic knowledge." International Journal of Remote Sensing 38, no. 5 (January 31, 2017): 1404–22. http://dx.doi.org/10.1080/01431161.2016.1278284.
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Rakhmonov, Sherzod, Uktam Umurzakov, Kosimdjon Rakhmonov, Iqbol Bozarov, and Ozodbek Karamatov. "Land Use and Land Cover Change in Khorezm, Uzbekistan." E3S Web of Conferences 227 (2021): 01002. http://dx.doi.org/10.1051/e3sconf/202122701002.
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This article depicts on discussions about land use and land cover change distribution in Khorezm province, Uzbekistan between 1987 and 2019. For the study Landsat 5 TM and Landsat 8 OLI respectively used to detect land use changes in the study area. Khorezm region affected by Aral Sea shrinkage having received salt wind from northeast of the region. Moreover, population increased within study period, making population density intense. Research is carried out to detect reflection of ecology and density in land use. RS techniques maximum likelihood employed to classify land use to generate land cover distribution map. In total seven class selected such as agricultural land, built up, bare land, lowland, saline land, sand and waterbody. The research of Khorezm region for 32 years has been thoroughly studied and found out that agricultural land, built up and saline land increased tremendously while lowland and bare soil are decreased accordingly. The result map can be used for decision makers and government bodies for future long term urban and regional planning.
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Adzandeh, E. A., D. Alaigba, and C. N. Nkemasong. "Application of Geospatial Techniques and Logistic Regression Model for Urban Growth Analysis in Limbe, Cameroon." Nigerian Journal of Environmental Sciences and Technology 4, no. 1 (March 2020): 138–51. http://dx.doi.org/10.36263/nijest.2020.01.0193.
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Little is known about the nature of ecosystem loss, rampant changes in land use and land cover (LULC) and urban growth taking place in Limbe. The aim of this study is to analyze urban growth in Limbe, Cameroon from 1986-2019 using geospatial techniques and Logistic Regression Model (LRM). Landsat Thematic Mapper (1986), Enhanced Thematic Mapper+ (2002) and Operational Land Imagery/Thermal Infrared Sensor (2019) were utilized in this study. The images were classified into land cover classes using supervised image classification algorithm in ENVI software. The classification output was subjected to LRM application to evaluate urban growth. Image difference of urban growth between 1986 and 2019 was calculated as dependent variable and the independent variables were produced by calculating the Euclidean distance and Buffer of built-up, waterbody, road and farmland as driving factor for urban growth. Future urban growth was determined for 2035 using the Land Change Modeler in IDRISI Selva. Classification overall accuracy for the three date were not less than 99%. LRM results show a good fit with relative operation characteristic of 0.8344 and Pseudo R2 of 0.21. Analysis of LULC shows that built-up increased from 3.5% (1986) to 17.6% (2019). An urban land expansion rate of about 23% was observed for 2035. Transition probability matrix revealed high probability (0.6345) of build-up to remaining build-up by 2035, while the probability for it changing to waterbody, bare land, farm land and vegetation are 0.1099, 0.0459, 0.1939 and 0.1221, respectively. This study successfully demonstrates the application of geo-spatial techniques and LRM for land use/land cover change detection and in understanding the urban growth dynamics. It also identifies the potential areas of future urban growth, which can help land use policy planners for making optimum decisions of land use planning and investment.
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Shrestha, Bhaskar, Qinghua Ye, and Nitesh Khadka. "Assessment of Ecosystem Services Value Based on Land Use and Land Cover Changes in the Transboundary Karnali River Basin, Central Himalayas." Sustainability 11, no. 11 (June 6, 2019): 3183. http://dx.doi.org/10.3390/su11113183.
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Land use and land cover change (LUCC) and its spatio-temporal characteristics are essential for natural resource management and sustainable development. LUCC is one of the major factors that affect the ecosystem and the services it provides. In this study, we used remote sensing techniques and a geographical information system to extract the land cover categories based on the Object-Based Image Analysis (OBIA) technique from Landsat TM/ETM/OLI satellite images in the transboundary Karnali River Basin (KRB, China and Nepal) of central Himalayas from 2000 to 2017. Spatio-temporal integrated methodology—Tupu was used to spatially show the LUCC as well as spatial characteristics of the arisen Tupu and shrunken Tupu. In addition, the ecosystem services value (ESV) were obtained and analyzed for each land cover category. In 2017, forest covered the highest area (33.45%) followed by bare area (30.3%), shrub/grassland (18.49%), agriculture (13.12%), snow/ice (4.32%), waterbody (0.3%) and built-up area (0.04%) in the KRB. From 2000 to 2017, the areas of forest, waterbody and snow/ice have decreased by 0.59, 6.14, and 1072.1 km2, respectively. Meanwhile, the areas of shrub/grassland, agriculture, barren land, and built-up categories have increased by 82.21, 1.44, 991.97, and 3.11 km2, respectively. These changes in the land cover have led to an increase in the ESV of the basin, especially the increase in shrub/grassland, agriculture, and water bodies (in the higher elevation). The total ESV of the basin was increased by $1.59 × 106 from 2000 to 2017. Anthropogenic factors together with natural phenomena drive LUCC in the basin and thus the ESV. The findings of this study could facilitate the basin-level policy formulation to guide future conservation and development management interventions.
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Aukes, Pieter J. K., Sherry L. Schiff, Jason J. Venkiteswaran, Richard J. Elgood, and John Spoelstra. "Size‐based characterization of freshwater dissolved organic matter finds similarities within a waterbody type across different Canadian ecozones." Limnology and Oceanography Letters 6, no. 2 (February 9, 2021): 85–95. http://dx.doi.org/10.1002/lol2.10180.
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Ćosić-Flajsig, Gorana, Barbara Karleuša, and Matjaž Glavan. "Integrated Water Quality Management Model for the Rural Transboundary River Basin—A Case Study of the Sutla/Sotla River." Water 13, no. 18 (September 17, 2021): 2569. http://dx.doi.org/10.3390/w13182569.
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The intensive use of soil and water resources results in a disbalance between the environmental and economic objectives of the river basin. The water quality management model supports good water status, especially downstream of dams and reservoirs, as in the case of the Sutla/Sotla river basin. This research aims to develop a new, improved integrated water quality management model of rural transboundary basins to achieve environmental objectives and protection of the Natura 2000 sites. The model uses river basin pressure analysis to assess the effects of climate and hydrological extreme impacts, and a programme of basic and supplementary measures. The impact assessment of BASE MODEL, PAST, and FUTURE scenarios was modelled using the soil and water assessment tool (SWAT) based on land use, climate and hydrological data, climate change, presence or lack of a reservoir, and municipal wastewater and agriculture measures. Eight future climate change scenarios were obtained with optimistic (RCP4.5) and pessimistic (RCP8.5) forecasts for two periods (2020–2050 and 2070–2100), both with and without a reservoir. The model shows that the most significant impacts on the waterbody come from the nutrients and sediment hotspots, also shows the risk of not achieving good water status, and water eutrophication risk. The modelled average annual increase in sediment is from 4 to 25% and in total N from 1 to 8%, while the change in total P is from −5 to 6%. The conducted analysis provides a base for the selection of tailor-made measures from the catalogue of the supplementary measures that will be outlined in future research.
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Darmadi, Mahidin, Siti Syifa Azzahra, and Munadiya Masrura. "Adsorption of Mercury(II) Ion in Aqueous Solution by Using Bentonite-Based Monolith." Key Engineering Materials 885 (May 2021): 77–84. http://dx.doi.org/10.4028/www.scientific.net/kem.885.77.
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The removal of mercury from the waterbody remains a severe challenge in ensuring environmental safety due to its highly toxic and non-biodegradable properties. Adsorption is an evidently effective method for heavy metal removal in water. This research aims to study the mercury (II) ion adsorption behavior in aqueous solution onto extruded natural bentonite in monolithic structure, bentonite-based monolith (BBM) adsorbent. BBM was characterized by XRD, BET, and SEM, the results verify BBM could improve adsorption performance assumed on its structure. Adsorption efficiency, isotherm model, and adsorption kinetic were investigated. Experiments were performed in a lab-scale batch reactor with mercury solution concentration varied from 1 to 5 mg/L. The maximum adsorption efficiency discovered to be 63,9%. The experimental data fitted well to Langmuir isotherm (non-linear) and kinetic model pseudo first order (non-linear), revealing the maximum monolayer capacity (Qo) of BBM to be 0,187 mg/g with Langmuir constants KL and aL are 0,215 L/g dan 1,151 L/mg respectively. These value confirms that BBM adsorbent encompasses tremendous potential for mercury (II) ion removal in a solution.
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Erturk, A., M. Gurel, E. Varol, A. Ekdal, M. Baloch, T. Dikerler, D. Z. Seker, and A. Tanik. "Analysis and modelling of land-based nutrient pollution by watershed models coupled with GIS: a case study from Turkey." Water Science and Technology 55, no. 3 (February 1, 2007): 115–22. http://dx.doi.org/10.2166/wst.2007.079.
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Diffuse pollution is usually temporally and spatially uncertain, and thus hard to analyze. In many cases, discretizing a diffuse source of pollution into individual point sources can ease diffuse pollution modelling and analysis, and therefore reduce high uncertainty especially in the spatial distribution of pollution loads. This is however a difficult task, since quite a number of sub-drainage areas, with complex structures and land-use properties, has to be delineated. Watershed models can be used to delineate the sub-drainage areas in a watershed with high accuracy and locate the related outlets which connect the sub-drainage areas to the main waterbody in a watershed. In this study, such an approach has been used on a case study to model the diffuse nutrient loads carried to streams that reach to a medium-sized lake in Turkey. The annual nutrient loads, which were calculated by using mathematical models, were then converted to a load-map with the help of a geographical information system.
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Oseni, A. E., and G. O. Ode. "Spatio-temporal Analysis of South Western States of Nigeria using Remote Sensing Techniques." Nigerian Journal of Environmental Sciences and Technology 4, no. 2 (October 2020): 298–313. http://dx.doi.org/10.36263/nijest.2020.02.0196.
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The south western states of Nigeria have witnessed urban growth over time and the effect of this is urban growth has resulted in loss of vegetation, waterbody, bare soil, mangroves and gain in built up area for residential and commercial purposes. This research utilizes Remote Sensing techniques in mapping of Land Use/Land Cover changes that has taken place in south western states of Nigeria between a period of 15 years from 2003 to 2018 at a five year interval using Multi temporal Landsat satellite images (MSS, TM, and ETM+).Using supervised classification algorithm, the images were classified into bare soil, built-up area, vegetation and water body, which was used to carry out change detection analysis or time series analysis. Change detection analyses were carried out on the imageries to obtain the physical expansion of the area due to various land use. Results obtained from the analysis of built-up area dynamics for fifteen years revealed that the states have been undergoing urban expansion processes at the detriment of other landcover. The expansion of the built-up area from the analysis shows that the urban center is spreading to adjoining non-built-up areas in all directions. The analysis and quantification of the spatial trend revealed that urban expansion patterns and developmental processes of the past trends and present trends can provide better understanding of the dynamics of spatial increase in built up area and guide for sustainable urban development planning for future urban growth.
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Kim, Jonggun, Bernard A. Engel, Youn Shik Park, Larry Theller, Indrajeet Chaubey, Dong Soo Kong, and Kyoung Jae Lim. "Development of Web-based Load Duration Curve system for analysis of total maximum daily load and water quality characteristics in a waterbody." Journal of Environmental Management 97 (April 2012): 46–55. http://dx.doi.org/10.1016/j.jenvman.2011.11.012.
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Peppa, M. V., S. B. Maharjan, S. P. Joshi, W. Xiao, and J. P. Mills. "GLACIAL LAKE EVOLUTION BASED ON REMOTE SENSING TIME SERIES: A CASE STUDY OF TSHO ROLPA IN NEPAL." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences V-3-2020 (August 3, 2020): 633–39. http://dx.doi.org/10.5194/isprs-annals-v-3-2020-633-2020.
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Abstract. Himalayan glaciers have retreated rapidly in recent years. Resultant glacial lakes in the region pose potential catastrophic threats to downstream communities, especially under a changing climate. The potential for Glacial Lake Outburst Floods (GLOFs) has increased and studies have assessed the risks of those in Nepal and prioritised several glacial lakes for urgent and closer investigation. The risk posed by the Tsho Rolpa Glacial Lake is one of the most serious in Nepal. To investigate the feasibility of high-frequency monitoring of glacial lake evolution by remote sensing, this paper proposes a workflow for automated glacial lake boundary extraction and evolution using a time series of Sentinel optical imagery. The waterbody is segmented and vectorised using bimodal histograms from water indices. The vectorised lake boundary is validated against reference data extracted from rigorous contemporary unmanned aerial vehicle (UAV)-based photogrammetric survey. Lake boundaries were subsequently extracted at four different epochs to evaluate the evolution of the lake, especially at the glacier terminus. The final lake area was estimated at 1.61 km2, significantly larger than the areal extent last formally reported. A 0.99 m/day maximum, and a 0.45 m/day average, horizontal glacier retreat rates were estimated. The reported research has demonstrated the potential of remote sensing time series to monitor glacial lake evolution, which is particularly important for lakes in remote mountain regions that are otherwise difficult to access.
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Píšková, Anna, Matěj Roman, Marie Bulínová, Matěj Pokorný, David Sanderson, Alan Cresswell, Juan Manuel Lirio, et al. "Late-Holocene palaeoenvironmental changes at Lake Esmeralda (Vega Island, Antarctic Peninsula) based on a multi-proxy analysis of laminated lake sediment." Holocene 29, no. 7 (April 2, 2019): 1155–75. http://dx.doi.org/10.1177/0959683619838033.
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We have studied laminated sediments from Lake Esmeralda, Vega Island, in order to reconstruct its history. We describe both inorganic and organic components of the sediment using a combination of the following analytical methods: x-ray fluorescence (XRF), x-ray diffraction (XRD), magnetic susceptibility measurement, chemical analysis for determination of cation exchange capacity, grain size determination, geochemical analyses (total inorganic carbon (TIC), total organic carbon (TOC), total sulphur (TS)), spectrophotometry, high-pressure liquid chromatography, and diatom assemblage and faunal remains characterization. The geochronology of the core was based on modelling optically stimulated luminescence ages and supported by laminae counting. The dating results imply a maximum age of ~400 years for the 177-cm long core and a period covered of ~200 years, suggesting (quasi-)annual laminae formation. Such a young age contradicts previous findings based on radiocarbon dating. Geomorphological evidence indicates that river capture isolated the lake catchment from upslope sediment delivery, effectively terminating accumulation ~230 years ago. Conversely, our short-term palaeoenvironmental record yields a subdecadal temporal resolution, which is unparalleled in comparison with other Antarctic palaeolimnological studies. Our interpretations of the geochemical and mineralogical proxy data give us insight into the past lake catchment and waterbody evolution, and lead us to recognize periods of enhanced weathering, bottom anoxia and to distinguish major lake level changes.
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Chen, Zhanzhuo, Min Huang, Daoye Zhu, and Orhan Altan. "Integrating Remote Sensing and a Markov-FLUS Model to Simulate Future Land Use Changes in Hokkaido, Japan." Remote Sensing 13, no. 13 (July 3, 2021): 2621. http://dx.doi.org/10.3390/rs13132621.
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As the second largest island in Japan, Hokkaido provides precious land resources for the Japanese people. Meanwhile, as the food base of Japan, the gradual decrease of the agricultural population and more intensive agricultural practices on Hokkaido have led its arable land use to change year by year, which has also caused changes to the whole land use pattern of the entire island of Hokkaido. To realize the sustainable use of land resources in Hokkaido, past and future changes in land use patterns must be investigated, and target-based land use planning suggestions should be given on this basis. This study uses remote sensing and GIS technology to analyze the temporal and spatial changes of land use in Hokkaido during the past two decades. The types of land use include cultivated land, forest, waterbody, construction, grassland, and others, by using the satellite images of the Landsat images in 2000, 2010, and 2019 to achieve this goal to make classification. In addition, this study used the coupled Markov-FLUS model to simulate and analyze the land use changes in three different scenarios in Hokkaido in the next 20 years. Scenario-based situational analysis shows that the cultivated land in Hokkaido will drop by about 25% in 2040 under the natural development scenario (ND), while the cultivated land area in Hokkaido will remain basically unchanged in cultivated land protection scenario (CP). In forest protection scenario (FP), the area of forest in Hokkaido will increase by 1580.8 km2. It is believed that the findings reveal that the forest land in Hokkaido has been well protected in the past and will be protected well in the next 20 years. However, in land use planning for future, Hokkaido government and enterprises should pay more attention to the protection of cultivated land.
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Suharyanto and Jun Matsushita. "Integrated basin-based wastewater management system for water pollution control in an enclosed waterbody of the upper Citarum River Basin, Indonesia: Case study of Saguling Reservoir." Lakes & Reservoirs: Research & Management 16, no. 3 (September 2011): 185–93. http://dx.doi.org/10.1111/j.1440-1770.2011.00473.x.
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Javid, Kanwal, Muhammad Ameer Nawaz Akram, Shazia Pervaiz, Rumana Siddiqui, and Nausheen Mazhar. "Index-based Approach in Relation to Built-up and LST Dynamics; A Study of Lahore, Pakistan." International Journal of Economic and Environmental Geology 12, no. 1 (June 8, 2021): 32–40. http://dx.doi.org/10.46660/ijeeg.vol12.iss1.2021.559.
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In 21st century, cities outpaced in size and also in density due to development of economic sector. Consequently, the wide spread expansion of urban areas is resulting in the loss of productive green cover and water bodies. Therefore, realizing this alarming situation, the present study is aimed to investigate and evaluate the pattern of urban expansion by considering two major land cover types (i) built-up area (ii) other classes (vegetation, waterbody, soil etc.) during the last six years (2015-2020). For this study Sentinel imagery was acquired from USGS Earth Explorer, while Modis Terra images were acquired from World View NASA. New built-up area index (NBUI), normalized difference vegetation index (NDVI), worldview water index (WV-WI) and land surface temperature (LST) were calculated in order to analyze variations in Lahore’s major land cover types and its varying temperature patterns. Spatial analysis presented the obvious impacts of land development on Lahore. NBUI indicated that the built-up area has increased drastically from 34.0% in 2015 to 84.2% in 2020; NDVI analysis depicted a decline from 0.76% to 0.73%, in the green spaces of Lahore during the study period; WV-WI portrayed inconsistent values of water bodies, a gift of massive rise in the built-up area in Lahore. LST results presented that the temperature was 42.21°C in 2015, which simultaneously increased and recorded at 49.51°C in 2020. The increase in LST exhibited the alarming situation for urban environment and can become threat to increase the air pollution level in Lahore. Therefore, this study will serve as a snapshot for policy makers to control the menace of unplanned urbanization by formulating stringent policies to protect environment.
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Regasa, Motuma Shiferaw, Michael Nones, and Dereje Adeba. "A Review on Land Use and Land Cover Change in Ethiopian Basins." Land 10, no. 6 (June 1, 2021): 585. http://dx.doi.org/10.3390/land10060585.
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Land Use Land Cover (LULC) changes analysis is one of the most useful methodologies to understand how the land was used in the past years, what types of detections are to be expected in the future, as well as the driving forces and processes behind these changes. In Ethiopia, Africa, the rapid variations of LULC observed in the last decades are mainly due to population pressure, resettlement programs, climate change, and other human- and nature-induced driving forces. Anthropogenic activities are the most significant factors adversely changing the natural status of the landscape and resources, which exerts unfavourable and adverse impacts on the environment and livelihood. The main goal of the present work is to review previous studies, discussing the spatiotemporal LULC changes in Ethiopian basins, to find out common points and gaps that exist in the current literature, to be eventually addressed in the future. A total of 25 articles, published from 2011 to 2020, were selected and reviewed, focusing on LULC classification using ArcGIS and ERDAS imagine software by unsupervised and maximum likelihood supervised classification methods. Key informant interview, focal group discussions, and collection of ground truth information using ground positioning systems for data validation were the major approaches applied in most of the studies. All the analysed research showed that, during the last decades, Ethiopian lands changed from natural to agricultural land use, waterbody, commercial farmland, and built-up/settlement. Some parts of forest land, grazing land, swamp/wetland, shrubland, rangeland, and bare/ rock out cropland cover class changed to other LULC class types, mainly as a consequence of the increasing anthropogenic pressure. In summary, these articles confirmed that LULC changes are a direct result of both natural and human influences, with anthropogenic pressure due to globalisation as the main driver. However, most of the studies provided details of LULC for the past decades within a specific spatial location, while they did not address the challenge of forecasting future LULC changes at the watershed scale, therefore reducing the opportunity to develop adequate basin-wide management strategies for the next years.
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Benjankar, Rohan, Ravin Kafle, Shanti Satyal, and Nirajan Adhikari. "Analyses of Spatial and Temporal Variations of Salt Concentration in Waterbodies Based on High Resolution Measurements Using Sensors." Hydrology 8, no. 2 (April 8, 2021): 64. http://dx.doi.org/10.3390/hydrology8020064.
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Studies have shown that salt concentrations are increasing in waterbodies such as lakes, rivers, wetlands, and streams in areas where deicers are commonly applied for winter road maintenance, resulting in degraded water quality. As the salt concentration varies spatially and temporally based on environmental and hydrological characteristics, we monitored high resolution (15 min) salt concentrations for a relatively long period (winter and spring season) at different sites (i.e., stream, urban-stream, roadside drain, and parking-lot drain) using multiple electric conductivity-based sensors. The salt concentrations were significantly different from each other considering individual sensors and different sites in both winter and spring seasons, which support past research results that concentration varies spatially. Parking-lot (1136 ± 674 ppm) and Roadside (701 ± 263 ppm) drain measured significantly higher concentration than for Stream (260 ± 60 ppm) and Urban-stream (562 ± 266 ppm) in the winter season. Similar trends were observed for the spring season, however, the mean concentrations were lower in the spring. Furthermore, salt concentrations were significantly higher during the winter (242 ± 47 ppm to 1695 ± 629 ppm) than for the spring (140 ± 23 ppm to 863 ± 440 ppm) season considering different sites, which have been attributed to the winter snow maintenance practice using deicers in past studies. All sites exceed the United States Environmental Protection Agency (USEPA) threshold (salt concentration higher than 230 mg/L) for chronic exposure level for 59% to 94% and 10% to 83% of days in winter and spring seasons, respectively. The study has highlighted the usefulness and advantages of high resolution (spatially and temporally) salt concentration measurement using sensor technology. Furthermore, the salt concentration in waterbodies can vary spatially and temporally within a small spatial scale, which may be important information for managing water quality locally. The high resolution measurements (i.e., 15 min) were helpful to capture the highest potential salt concentrations in the waterbody. Therefore, the sensor technology can help to measure high resolution salt concentrations, which can be used to quantify impacts of high salt concentrations, e.g., application of deicer for winter road maintenance on aquatic systems based on the criteria developed by USEPA.
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Hao, Binfei, Mingguo Ma, Shiwei Li, Qiuping Li, Dalei Hao, Jing Huang, Zhongxi Ge, Hong Yang, and Xujun Han. "Land Use Change and Climate Variation in the Three Gorges Reservoir Catchment from 2000 to 2015 Based on the Google Earth Engine." Sensors 19, no. 9 (May 7, 2019): 2118. http://dx.doi.org/10.3390/s19092118.
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Possible environmental change and ecosystem degradation have received increasing attention since the construction of Three Gorges Reservoir Catchment (TGRC) in China. The advanced Google Earth Engine (GEE) cloud-based platform and the large number of Geosciences and Remote Sensing datasets archived in GEE were used to analyze the land use and land cover change (LULCC) and climate variation in TGRC. GlobeLand30 data were used to evaluate the spatial land dynamics from 2000 to 2010 and Landsat 8 Operational Land Imager (OLI) images were applied for land use in 2015. The interannual variations in the Land Surface Temperature (LST) and seasonally integrated normalized difference vegetation index (SINDVI) were estimated using Moderate Resolution Imaging Spectroradiometer (MODIS) products. The climate factors including air temperature, precipitation and evapotranspiration were investigated based on the data from the Global Land Data Assimilation System (GLDAS). The results indicated that from 2000 to 2015, the cultivated land and grassland decreased by 2.05% and 6.02%, while the forest, wetland, artificial surface, shrub land and waterbody increased by 3.64%, 0.94%, 0.87%, 1.17% and 1.45%, respectively. The SINDVI increased by 3.209 in the period of 2000-2015, while the LST decreased by 0.253 °C from 2001 to 2015. The LST showed an increasing trend primarily in urbanized area, with a decreasing trend mainly in forest area. In particular, Chongqing City had the highest LST during the research period. A marked decrease in SINDVI occurred primarily in urbanized areas. Good vegetation areas were primarily located in the eastern part of the TGRC, such as Wuxi County, Wushan County, and Xingshan County. During the 2000–2015 period, the air temperature, precipitation and evapotranspiration rose by 0.0678 °C/a, 1.0844 mm/a, and 0.4105 mm/a, respectively. The climate change in the TGRC was influenced by LULCC, but the effect was limited. What is more, the climate change was affected by regional climate change in Southwest China. Marked changes in land use have occurred in the TGRC, and they have resulted in changes in the LST and SINDVI. There was a significantly negative relationship between LST and SINDVI in most parts of the TGRC, especially in expanding urban areas and growing forest areas. Our study highlighted the importance of environmental protection, particularly proper management of land use, for sustainable development in the catchment.
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Bowen, Landen, Kara Springsteen, Hannah Feldstein, Mary Frecker, Timothy W. Simpson, and Paris von Lockette. "Development and Validation of a Dynamic Model of Magneto-Active Elastomer Actuation of the Origami Waterbomb Base." Journal of Mechanisms and Robotics 7, no. 1 (February 1, 2015). http://dx.doi.org/10.1115/1.4029290.
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Of special interest in the growing field of origami engineering is self-folding, wherein a material is able to fold itself in response to an applied field. In order to simulate the effect of active materials on an origami-inspired design, a dynamic model is needed. Ideally, the model would be an aid in determining how much active material is needed and where it should be placed to actuate the model to the desired position(s). A dynamic model of the origami waterbomb base, a well-known and foundational origami mechanism, is developed using adams 2014, a commercial multibody dynamics software package. Creases are approximated as torsion springs with both stiffness and damping. The stiffness of an origami crease is calculated, and the dynamic model is verified using the waterbomb. An approximation of the torque produced by magneto-active elastomers (MAEs) is calculated and is used to simulate MAE-actuated self-folding of the waterbomb. Experimental validation of the self-folding waterbomb model is performed, verifying that the dynamic model is capable of accurate simulation of the fold angles.
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Hanna, Brandon H., Spencer P. Magleby, Robert J. Lang, and Larry L. Howell. "Force–Deflection Modeling for Generalized Origami Waterbomb-Base Mechanisms." Journal of Applied Mechanics 82, no. 8 (August 1, 2015). http://dx.doi.org/10.1115/1.4030659.
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The origami waterbomb base (WB) is a single-vertex bistable mechanism that can be generalized to accommodate various geometric, kinematic, and kinetic needs. The traditional WB consists of a square sheet that has four mountain folds alternating with five valley folds (eight folds total) around the vertex in the center of the sheet. This special case mechanism can be generalized to create two classes of waterbomb-base-type mechanisms that allow greater flexibility for potential application. The generalized WB maintains the pattern of alternating mountain and valley folds around a central vertex but it is not restricted to eight total folds. The split-fold waterbomb base (SFWB) is made by splitting each fold of a general WB into two “half folds” of the same variety as the parent fold. This study develops kinematic, potential energy, and force–deflection models for the rigid-foldable, developable, symmetric cases of the generalized WB and the SFWB, and investigates the relative effects of numbers of folds and split-fold panel size, on device behavior. The effect of selected key parameters is evaluated, and equations are provided to enable the exploration of other important parameters that may be of interest in the design and analysis of specific mechanisms. The similarities and differences between the two general forms are discussed, including tunability of the bistable and force–deflection behavior of each.
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Qiu, Chen, Ketao Zhang, and Jian S. Dai. "Repelling-Screw Based Force Analysis of Origami Mechanisms." Journal of Mechanisms and Robotics 8, no. 3 (March 7, 2016). http://dx.doi.org/10.1115/1.4031458.
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This paper provides an approach to model the reaction force of origami mechanisms when they are deformed. In this approach, an origami structure is taken as an equivalent redundantly actuated mechanism, making it possible to apply the forward-force analysis to calculating the reaction force of the origami structure. Theoretical background is provided in the framework of screw theory, where the repelling screw is introduced to integrate the resistive torques of folded creases into the reaction-force of the whole origami mechanism. Two representative origami structures are then selected to implement the developed modeling approach, as the widely used waterbomb base and the waterbomb-based integrated parallel mechanism. With the proposed kinematic equivalent, their reaction forces are obtained and validated, presenting a ground for force analysis of origami-inspired mechanisms.
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Kwok, Tsz-Ho. "Geometry-Based Thick Origami Simulation." Journal of Mechanical Design 143, no. 6 (November 17, 2020). http://dx.doi.org/10.1115/1.4048744.
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Abstract Origami is the art of creating a three-dimensional (3D) shape by folding paper. It has drawn much attention from researchers, and the designs that origami has inspired are used in various engineering applications. Most of these designs are based on familiar origami patterns and their known deformations, but origami patterns were originally intended for materials of near-zero thickness, primarily paper. To use the designs in engineering applications, it is necessary to simulate origami in a way that enables designers to explore and understand the designs while taking the thickness of the material to be folded into account. Because origami is primarily a problem in geometric design, this paper develops a geometric simulation for thick origami. The actuation, constraints, and assignment of mountain and valley folds in origami are also incorporated into the geometric formulation. The experimental results show that the proposed method is efficient and accurate. The method can successfully simulate a flat-foldable degree-four vertex, two different action origami, the bistable property of a waterbomb base, and the elasticity of non-rigid origami panels.
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Chen, Guimin, Spencer P. Magleby, and Larry L. Howell. "Membrane-Enhanced Lamina Emergent Torsional Joints for Surrogate Folds." Journal of Mechanical Design 140, no. 6 (April 17, 2018). http://dx.doi.org/10.1115/1.4039852.
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Lamina emergent compliant mechanisms (including origami-adapted compliant mechanisms) are mechanical devices that can be fabricated from a planar material (a lamina) and have motion that emerges out of the fabrication plane. Lamina emergent compliant mechanisms often exhibit undesirable parasitic motions due to the planar fabrication constraint. This work introduces a type of lamina emergent torsion (LET) joint that reduces parasitic motions of lamina emergent mechanisms, and presents equations for modeling parasitic motion of LET joints. The membrane joint also makes possible one-way joints that can ensure origami-based mechanisms emerge from their flat state (a change point) into the desired configuration. Membrane-enhanced LET (M-LET) joints, including one-way surrogate folds, are described here and show promise for use in a wide range of compliant mechanisms and origami-based compliant mechanisms. They are demonstrated as individual joints and in mechanisms such as a kaleidocycle (a 6R Bricard linkage), degree-4 origami vertices (spherical mechanisms), and waterbomb base mechanisms (an 8R multi-degrees-of-freedom origami-based mechanism).
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Bowen, Landen, Kara Springsteen, Mary Frecker, and Timothy Simpson. "Trade Space Exploration of Magnetically Actuated Origami Mechanisms." Journal of Mechanisms and Robotics 8, no. 3 (March 7, 2016). http://dx.doi.org/10.1115/1.4032406.
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Self-folding origami has the potential to be utilized in novel areas such as self-assembling robots and shape-morphing structures. Important decisions in the development of such applications include the choice of active material and its placement on the origami model. With proper active material placement, the error between the actual and target shapes can be minimized along with cost, weight, and input energy requirements. A method for creating magnetically actuated dynamic models and experimentally verifying their results is briefly reviewed, after which the joint stiffness and magnetic material approximations used in the dynamic model are discussed in more detail. Through the incorporation of dynamic models of magnetically actuated origami mechanisms into the Applied Research Laboratory's trade space visualizer (atsv), the trade spaces of self-folding dynamic models of the waterbomb base and Shafer's frog tongue are explored. Finally, a design tradeoff is investigated between target shape approximation error and the placement of magnetic material needed to reach a target shape. These two examples demonstrate the potential use of this process as a design tool for other self-folding origami mechanisms.
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Robertson, Matthew A., Ozdemir Can Kara, and Jamie Paik. "Soft pneumatic actuator-driven origami-inspired modular robotic “pneumagami”." International Journal of Robotics Research, March 18, 2020, 027836492090990. http://dx.doi.org/10.1177/0278364920909905.
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This article presents a new modular robotic platform for enabling reconfigurable, actively controlled, high-degree-of-freedom (high-DoF) systems with compact form factor. The robotic modules exploit the advantages of origami-inspired construction methods and materials, and soft pneumatic actuators (SPAs) to achieve an actuator embedded, parallel kinematic mechanism with three independently controlled “waterbomb” base legs. The multi-material, layer-fabricated body of the modules features selectively compliant flexure hinge elements between rigid panels that define the module as a kinematic 6R spherical joint. The precision layer-fabrication technique is also used to form embedded distribution channels within the module base to connect actuators to onboard control hardware. A decentralized control architecture is applied by integrating each module with small-scale solenoid valves, communication electronics, and sensors. This design approach enables a single pneumatic supply line to be shared between modules, while still allowing independent control of each leg joint, driven by soft, inflatable pouch actuators. A passive pneumatic relay is also designed and incorporated in each module to leverage the coupled, inverted inflation, and exhaust states between antagonistic actuator pairs allowing both to be controlled by a single solenoid valve. A prototype module is presented as the first demonstration of integrated modular origami and SPA design, or pneumagami, which allows predefined kinematic structural mechanisms to locally prescribe specific motions by active effect, not just through passive compliance, to dictate task space and motion. The design strategy facilitates the composition of lightweight, high-strength robotic structures with many DoFs that will benefit various fields such as wearable robotics.
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Feng, Huijuan, Jiayao Ma, Yan Chen, and Zhong You. "Twist of Tubular Mechanical Metamaterials Based on Waterbomb Origami." Scientific Reports 8, no. 1 (June 22, 2018). http://dx.doi.org/10.1038/s41598-018-27877-1.
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Liu, Chenying, Perla Maiolino, and Zhong You. "A 3D-Printable Robotic Gripper Based on Thick Panel Origami." Frontiers in Robotics and AI 8 (September 8, 2021). http://dx.doi.org/10.3389/frobt.2021.730227.
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Origami has been a source of inspiration for the design of robots because it can be easily produced using 2D materials and its motions can be well quantified. However, most applications to date have utilised origami patterns for thin sheet materials with a negligible thickness. If the thickness of the material cannot be neglected, commonly known as the thick panel origami, the creases need to be redesigned. One approach is to place creases either on top or bottom surfaces of a sheet of finite thickness. As a result, spherical linkages in the zero-thickness origami are replaced by spatial linkages in the thick panel one, leading to a reduction in the overall degrees of freedom (DOFs). For instance, a waterbomb pattern for a zero-thickness sheet shows multiple DOFs while its thick panel counterpart has only one DOF, which significantly reduces the complexity of motion control. In this article, we present a robotic gripper derived from a unit that is based on the thick panel six-crease waterbomb origami. Four such units complete the gripper. Kinematically, each unit is a plane-symmetric Bricard linkage, and the gripper can be modelled as an assembly of Bricard linkages, giving it single mobility. A gripper prototype was made using 3D printing technology, and its motion was controlled by a set of tendons tied to a single motor. Detailed kinematic modelling was done, and experiments were carried out to characterise the gripper’s behaviours. The positions of the tips on the gripper, the actuation force on tendons, and the grasping force generated on objects were analysed and measured. The experimental results matched well with the analytical ones, and the repeated tests demonstrate that the concept is viable. Furthermore, we observed that the gripper was also capable of grasping non-symmetrical objects, and such performance is discussed in detail in the paper.
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Nwaogu, Chukwudi, Onyedikachi J. Okeke, Olusola O. Fadipe, Kehinde A. Bashiru, and Vilém Pechanec. "Is Nigeria losing its natural vegetation and landscape? Assessing the landuse-landcover change trajectories and effects in Onitsha using remote sensing and GIS." Open Geosciences 9, no. 1 (December 29, 2017). http://dx.doi.org/10.1515/geo-2017-0053.
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AbstractOnitsha is one of the largest commercial cities in Africa with its population growth rate increasing arithmetically for the past two decades. This situation has direct and indirect effects on the natural resources including vegetation and water. The study aimed at assessing land use-land cover (LULC) change and its effects on the vegetation and landscape from 1987 to 2015 using geoinformatics. Supervised and unsupervised classifications including maximum likelihood algorithm were performed using ENVI 4.7 and ArcGIS 10.1 versions. The LULC was classified into 7 classes: built-up areas (settlement), waterbody, thick vegetation, light vegetation, riparian vegetation, sand deposit (bare soil) and floodplain. The result revealed that all the three vegetation types decreased in areas throughout the study period while, settlement, sand deposit and floodplain areas have remarkable increase of about 100% in 2015 when compared with the total in 1987. Number of dominant plant species decreased continuously during the study. The overall classification accuracies in 1987, 2002 and 2015 was 90.7%, 92.9% and 95.5% respectively. The overall kappa coefficient of the image classification for 1987, 2002 and 2015 was 0.98, 0.93 and 0.96 respectively. In general, the average classification was above 90%, a proof that the classification was reliable and acceptable.
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Rodrigo, María Antonia, Adriana García, and Allan R. Chivas. "Carbon stable isotope composition of charophyte organic matter in a small and shallow Spanish water body as a baseline for future trophic studies." Journal of Limnology, December 29, 2015. http://dx.doi.org/10.4081/jlimnol.2015.1268.
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<p>Quantitative descriptions of foodweb structure based on isotope niche space require knowledge of producers’ isotopic signatures. In freshwater ecosystems charophytes are one of the main components of submerged vegetation and the feeding base for many herbivorous consumers, but knowledge about their organic carbon isotopic signatures is sparse. In this study, the δ<sup>13</sup>C organic values (and organic %C and %N) of the four species of submerged macrophytes (three charophytes - <em>Chara hispida</em>, <em>Nitella hyalina</em> and <em>Tolypella glomerata </em>- and one angiosperm, <em>Myriophyllum spicatum</em>) growing in a newly created shallow pond were measured monthly over a period of one year, to discern if i) all charophyte species susceptible to being food for consumers and growing in the same waterbody have the same C isotopic composition; ii) the δ<sup>13</sup>C values of a charophyte species change on a seasonal and spatial scale; iii) the different parts (apical nodes, internodes, rhizoids, reproductive organs, oospores) of a charophyte species have the same isotopic composition. The δ<sup>13</sup>C, %C and %N values of organic matter in the sediments where the plants were rooted were also measured as well as several limnological variables. The δ<sup>13</sup>C values for the angiosperm (-13.7±0.7‰) indicated <sup>13</sup>C-enrichment, whereas the <em>N. hyalina</em> δ<sup>13</sup>C values were the most negative (-22.4±0.7‰). The mean δ<sup>13</sup>C value for <em>C. hispida </em>was -19.0±1.0‰ and -20.7±0.8‰ for <em>T. glomerata.</em> <em>C. hispida</em> δ<sup>13</sup>C values had a significant seasonal variation with <sup>13</sup>C-poor values in the cold season, and slight spatial differences. Statistically significant differences were found between charophyte rhizoids (<sup>13</sup>C-enriched) and the other parts of the thalli. The δ<sup>13</sup>C values in the sediments varied throughout time (-13‰ to -26‰). The C content was lower in the charophytes than in the angiosperm and there were no large differences among the charophytes. Charophyte fructifications were enriched in organic C compared to the thalli parts. The study provides an isotopic baseline for further studies for the elucidation of higher trophic-level relationships which are particularly complex in shallow water bodies where interactions between the pelagic and the benthic zones are intricate.</p>