New formulation and optimization methods for water sensor placement

This research had as its objective the investigation of an alternative strategy for soil sensor placement to be used in citrus orchards irrigated by micro sprinkler. An experiment was carried out in a Tahiti lemon orchard under three irrigation intervals of 1, 2 and 3 days. Soil water potential, soil water content distribution and root water extraction were monitored by a time-domain-reflectometry (TDR) in several positions in soil profiles radial to the trees. Root length and root length density were determined from digital root images at the same positions in the soil profiles where water content was monitored. Results showed the importance of considering root water extraction in the definition of soil water sensor placement. The profile regions for soil water sensor placement should correspond to the intersection of the region containing at least 80% of total root length and the region of at least 80% of total water extraction. In case of tensiometers, the region of soil water potential above -80 kPa should be included in the intersection.

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Flow and Uptake Patterns Affecting Soil Water Sensor Placement for Drip Irrigation Management

Transactions of the ASAE ◽

10.13031/2013.27703 ◽

1996 ◽

Vol 39 (6) ◽

pp. 2007-2016 ◽

Cited By ~ 26

Author(s):

E. F. Coelho ◽

D. Or

Keyword(s):

Soil Water ◽

Drip Irrigation ◽

Irrigation Management ◽

Sensor Placement ◽

Water Sensor

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Topology Optimization of Micromachined Structures With Surface Micromachining Manufacturing Constraints

Volume 1: 32nd Design Automation Conference, Parts A and B ◽

10.1115/detc2006-99341 ◽

2006 ◽

Author(s):

Aravind Alwan ◽

G. K. Ananthasuresh

Keyword(s):

Topology Optimization ◽

Optimization Methods ◽

Manufacturing Cost ◽

Manufacturing Constraints ◽

Surface Micromachining ◽

Out Of Plane ◽

Gradient Based ◽

Plane Direction ◽

New Formulation ◽

Design Parameterization

Topology optimization methods have been shown to have extensive application in the design of microsystems. However, their utility in practical situations is restricted to predominantly planar configurations due to the limitations of most microfabrication techniques in realizing structures with arbitrary topologies in the direction perpendicular to the substrate. This study addresses the problem of synthesizing optimal topologies in the out-of-plane direction while obeying the constraints imposed by surface micromachining. A new formulation that achieves this by defining a design space that implicitly obeys the manufacturing constraints with a continuous design parameterization is presented in this paper. This is in contrast to including manufacturing cost in the objective function or constraints. The resulting solutions of the new formulation obtained with gradient-based optimization directly provide the photolithographic mask layouts. Two examples that illustrate the approach for the case of stiff structures are included.

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Risk aware optimization of water sensor placement

Proceedings of the Genetic and Evolutionary Computation Conference Companion ◽

10.1145/3449726.3459477 ◽

2021 ◽

Author(s):

Antonio Candelieri ◽

Andrea Ponti ◽

Francesco Archetti

Keyword(s):

Sensor Placement ◽

Water Sensor

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Management of trickle irrigation for banana: Hydrodynamic processes and sensor placement at the root zone

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v25n5p312-318 ◽

2021 ◽

Vol 25 (5) ◽

pp. 312-318

Author(s):

Edvaldo B. Santana Junior ◽

Eugênio F. Coelho ◽

Marcelo R. dos Santos ◽

Alisson J. P. da Silva ◽

João B. R. da S. Reis ◽

...

Keyword(s):

Soil Water ◽

Root Zone ◽

Block Design ◽

Sensor Placement ◽

Hydrodynamic Process ◽

Trickle Irrigation ◽

Irrigation Systems ◽

Flow Rates ◽

Water Sensor ◽

Hydrodynamic Processes

ABSTRACT Information on soil hydrodynamic processes assists in explaining the soil-water-plant relationship and has practical applications to irrigation management, such as the definition of soil water sensor placement. The objective of this study was to detail the hydrodynamic process in the soil root zone and to define the location for placement of soil water sensor under different configurations of trickle irrigation in banana crops. Three micro-sprinkler emitters with flow rates of 70 (T1), 53 (T2), 35 L h-1 (T3), and two drip system, one with one drip line per row of plants (T4), and another with two drip lines per row of plants (T5) were evaluated. The experiment was conducted in a randomized block design with five repetitions. Higher water extraction was found for irrigation systems with higher flow rates for all configurations of trickle irrigation systems. Soil moisture sensors in drip systems should be placed at distances of 0.75 to 0.81 m from the pseudo stem and at depths of 0.33 to 0.44 m. Under micro-sprinkler systems, soil water sensors should be placed at 0.75, 0.77 and 0.83 m from the pseudo stem towards to the emitter and at depths of 0.33, 0.48 and 0.55 m for emitter flow rates of 35, 53 and 70 L h-1, respectively.

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Sensor Placement with Two-Dimensional Equal Arc Length Non-Uniform Sampling for Underwater Terrain Deformation Monitoring

Journal of Marine Science and Engineering ◽

10.3390/jmse9090954 ◽

2021 ◽

Vol 9 (9) ◽

pp. 954

Author(s):

Chunying Xu ◽

Junwei Hu ◽

Jiawang Chen ◽

Yongqiang Ge ◽

Ruixin Liang

Keyword(s):

Sensor Placement ◽

Sensor Arrays ◽

Optimization Methods ◽

Deformation Monitoring ◽

Water Tank ◽

Two Dimensional ◽

Arc Length ◽

Mems Accelerometer ◽

Uniform Sampling ◽

Non Uniform Sampling

Sensor placement plays an important role in terrain deformation monitoring systems and has an essential effect on data collection. The difficulty of sensor placement entails obtaining the most adequate and reliable information with the fewest number of sensors. Most sensor placement schemes are currently based on randomized non-uniform sampling and probability statistics, such as structural modality and optimization methods, which are difficult to directly apply due to the randomness and spatial heterogeneity of terrain deformation. In this study, the placement conditions of two-dimensional non-uniform sampling with equal arc length were deduced for underwater terrain deformation monitoring based on the MEMS accelerometer network. In order to completely reconstruct the underwater terrain, the arc length interval of the sensors should be less than 12Ω (Ω is the maximum frequency of the detected terrain). The maximum MRE and maximum RMSE were both less than seven percent in a terrain deformation monitoring experiment and a water tank test. The research results help technicians apply contact sensor arrays for underwater terrain monitoring.

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