Study of accuracy and sensing volume of a wide range of established and low-cost soil water content probes

2020 ◽  
Author(s):  
Miguel A. Campo-Bescós ◽  
Iban Iturria ◽  
Unai Gomez ◽  
Rafael Gimenez ◽  
Javier Casali ◽  
...  
Keyword(s):  
Soil Water ◽  
Low Cost ◽  
Gravimetric Method ◽  
Transport Processes ◽  
Large Variability ◽  
Electromagnetic Sensors ◽  
Wide Range ◽  
Mean Square Errors ◽  
Risk Analysis And Management ◽  
Selection Of

<p>Continuous soil moisture content monitoring is key to understand the soil and water flow and transport processes and their impact on a wide range of environmental change and quality processes. Nowadays, there are a wide variety of electromagnetic sensors for estimating soil volumetric content. These include those from established manufacturers (>50€) and low-cost (<50€) amateur electronics enthusiasts with open-source projects. For each sensor, the manufacturer typically provides both a calibration function and an estimation of the sensing volume of the device. The objective of this work is to evaluate the performance –regarding the accuracy and effective sensing volume– of a wide variety of soil water sensors and to compare these results with those provided originally by the respective manufacturer. Twenty-five different electromagnetic sensors representative of the current best-known commercial (19) and the low-cost brands (6) were tested in the laboratory using 3 soils of contrasting texture. Benchmark values for comparison were obtained by the gravimetric method. The sensing volume for each probe was characterized by recording readings while the probes approached a water surface. The Root Mean Square Errors of the sensors ranged from 0.02 to 0.10 cm<sup>3</sup>/cm<sup>3</sup>, and the sensing volume of the different probes exhibited a large variability, ranging from 0.5 to 1500 cm<sup>3</sup>. Importantly, the probes evaluated in laboratory conditions showed different errors for each soil type. The loamy soil readings presented the smallest errors, followed by sandy and clayey soils. No statistically significant differences were found in measurement accuracy between low-cost and higher-priced probes. From the study of the sensing volume explored, with the exception of one case, it can be concluded that the low-cost probes generally explore a smaller volume than the established probes. The selection of the appropriate probe based on its sensing value could be important for different types of risk analysis and management applications.</p>

The relationship between thermal conductivity and matric suction of soils

2021 ◽  
Author(s):  
Sen Lu
Keyword(s):  
Thermal Conductivity ◽  
Soil Water ◽  
Land Surface ◽  
Matric Suction ◽  
Dew Point ◽  
Pulse Technique ◽  
Highly Nonlinear ◽  
Wide Range ◽  
Mean Square Errors ◽  
The Relationship

<p>The soil thermal conductivity (λ) and matric suction of soil water (h, the negative of matric potential) relationship has been widely used in land surface models for estimating soil temperature and heat flux following the McCumber and Pielke (1981, MP81) λ-h model. However, few datasets are available for evaluating the accuracy and feasibility of the MP81 λ-h model under various soil and moisture conditions. In this study, we developed a new λ-h model and compared its performance with that of the MP81 model using measurements on 18 soils with a wide range of textures, water contents and bulk densities. The heat pulse technique was used to measure λ, and the suction table, micro-tensiometers, pressure plate device, and the dew point potentiometer were applied to obtain soil water retention curves at the appropriate suction ranges. In the range of pF (the common logarithm of h in cm)≤3, the λ-h relationships were highly nonlinear and varied strongly with soil texture and bulk density. In the dry range (i.e., pF > 3), there existed a universal λ-h relationship for all soil textures and bulk densities, and an exponential function was established to describe the relationship. Independent evaluations using λ-h data on five intact soil samples showed that the new model produced accurate λ data from pF values with root mean square errors (RMSE) with the range of 0.03–0.18W m<sup>−1</sup> K<sup>−1</sup>. While, large errors (RMSEs within 0.17–0.36W m<sup>−1</sup> K<sup>−1</sup>) were observed with λ estimates from the MP81 model. </p>

Simultaneous Calibration for MEMS Gyroscopes of the Rocket IMU

2014 ◽  
Vol 896 ◽  
pp. 656-659 ◽  
Author(s):  
Wahyudi ◽  
Adhi Susanto ◽  
Wahyu Widada ◽  
Sasongko P. Hadi
Keyword(s):  
Low Cost ◽  
Angular Rate ◽  
Calibration Method ◽  
Sensor Technology ◽  
Measurement Unit ◽  
Angular Rate Sensor ◽  
Motion Simulator ◽  
Wide Range ◽  
Mems Gyroscopes ◽  
Mean Square Errors

MEMS (Microelectromechanical System), as an advanced sensor technology, is low power, low cost, and small size. Gyroscope sensor produced with microelectromechanical technology is an angular rate sensor. IMU (Inertial Measurement Unit) sensor for rocket should have a very wide range of measurements. At the beginning of the motion, the rocket accelereation is very high, for which the rocket IMU requires a multisensor with different sensitivity. This paper presents the design of the rocket IMU and its calibration method for all MEMS gyroscopes. Calibration for each sensor is necessary including its varying characteristics. The calibration of the gyroscope sensors use three-axis motion simulator model ST 3176 with resolutions 0.00001 for all axes. Simultaneous calibration was mutually applied which require a short calibration time. The results show that root mean square errors (RMSE) of the calibrated gyroscope for all axes are under 2.5 %. Therefore, that the calibrated gyroscope can be used in the proposed real application.

scholarly journals A generalized model between thermal conductivity and matric suction of soils

2021 ◽  
Author(s):  
Sen Lu
Keyword(s):  
Thermal Conductivity ◽  
Soil Water ◽  
Land Surface ◽  
Matric Suction ◽  
Dew Point ◽  
Soil Thermal Conductivity ◽  
Pulse Technique ◽  
Highly Nonlinear ◽  
Wide Range ◽  
Mean Square Errors

<p>Soil thermal conductivity (λ) is an important physical property in land surface parameterization. The soil thermal conductivity (λ) and matric suction of soil water (h, the negative of matric potential) relationship has been widely used in land surface models for estimating soil temperature and heat flux following the McCumber and Pielke (1981, MP81) λ-h model. However, few datasets are available for evaluating the accuracy and feasibility of the MP81 λ-h model under various soil and moisture conditions. In this study, we developed a new λ-h model and compared its performance with that of the MP81 model using measurements on 18 soils with a wide range of textures, water contents and bulk densities. The heat pulse technique was used to measure λ, and the suction table, micro-tensiometers, pressure plate device, and the dew point potentiometer were applied to obtain soil water retention curves at the appropriate suction ranges. In the range of pF (the common logarithm of h in cm)≤3, the λ-h relationships were highly nonlinear and varied strongly with soil texture and bulk density. In the dry range (i.e., pF > 3), there existed a universal λ-h relationship for all soil textures and bulk densities, and an exponential function was established to describe the relationship. Independent evaluations using λ-h data on five intact soil samples showed that the new model produced accurate λ data from pF values with root mean square errors (RMSE) with the range of 0.03–0.18Wm−1 K−1. While, large errors (RMSEs within 0.17–0.36Wm−1 K−1) were observed with λ estimates from the MP81 model. </p>

A Travel Blog as a Space for Creation and Communication of Travel Models

2016 ◽  
Vol 40 (0) ◽  
pp. 119-0 ◽  
Author(s):  
Irina Morozova
Keyword(s):  
Content Analysis ◽  
Low Cost ◽  
Future Research ◽  
Testing Method ◽  
Wide Range ◽  
Definition Of ◽  
Travel Blog ◽  
Practical Implications ◽  
Selection Of

Purpose. The purpose of this article is to present the variety of travel models which are conveyed and promoted by amateur travel blogs. Methods. The research sample was constituted on the bases of selected Polish travel blogs which promote travel models. The basic criteria for the selection of these particular blogs was the representativeness and popularity among readers. The testing method was content analysis of selected blogs. Findings. The present study suggests a classification of travel blogs. The research hypothesis claiming that the authors of travel blogs publicize travel models was confirmed. Research and conclusions limitations. The study is focused only on amateur travel blogs which are written in Polish. During the process of research, the author focused on a range of topics of the posts as well as on the publication genres. The present study includes blogs about world travels, travelling with children as well asdogs and low-cost travels. Practical implications. The results of this study indicate a wide range of possible future research studies regarding travel blogs from different perspectives. Originality. This article attempts to establish the definition of a travel model and the main characteristics of a travel blogger which aspire to become a travelebrity. A classification of travel blogs using the 'travel model' key is also provided. Type of paper. The article presents the results of empirical research conducted by the author.

scholarly journals Design and fabrication of low-cost micromachining system for prototyping printed circuit boards

2021 ◽  
Author(s):  
Dhinesh S K ◽  
◽  
Senthil Kumar K L ◽  
Megalingam A ◽  
Gokulraj A P ◽  
...  
Keyword(s):  
Printed Circuit Boards ◽  
Low Cost ◽  
Working Environment ◽  
Circuit Boards ◽  
Printed Circuit ◽  
Milling Operation ◽  
Wide Range ◽  
Complex Shapes ◽  
The Cost ◽  
Selection Of

Printed circuit boards (PCBs) have a portentous position in constructing modern electronic equipment. Currently, chemical etching is the process used to produce PCBs at huge volumes, which is not suitable for preparing prototypes. The working environment is also not an encouraging one. There is no economical way to manufacture PCBs in low volumes, which is the basic requirement for Small and Medium Scale Enterprises (SMEs). Prototyping the desired circuit boards, prior to the mass production, is essential to avoid major losses by producing faulty designs. Developing a low-cost machine for prototyping PCBs may overcome these drawbacks. Hence, in this work, a machine capable of performing PCB mechanical milling operation on wide range of materials like copper/epoxy boards and flexible substrates has been developed. The machine developed is capable of milling lines that are 0.3 mm in width and 0.46 mm in depth. The performance of the machine reveals that it can mill any complex shapes and designs with expected accuracy. Selection of hardware components according to the needs would reduce the cost and programming snag further, which makes it affordable to SMEs.

Design and Characteristic Analysis of Amalgamated Transparent Materials for Armor Structures Using Defeating Ballistic Experimentation

2018 ◽  
Author(s):  
Emad Attalla ◽  
Badih Jawad ◽  
Steve Grate ◽  
Vernon Fernandez ◽  
Sabah Abro ◽  
...  
Keyword(s):  
Low Cost ◽  
Research Work ◽  
Computer Software ◽  
Yield Response ◽  
Material Strength ◽  
Matrix Glass ◽  
Characteristic Analysis ◽  
Ballistic Impacts ◽  
Wide Range ◽  
Selection Of

In armored platforms industry, the dominant material solution for ballistic transparency protection applications is relatively low-cost polycarbonate matrix glass. This research work aims to investigate the effects of geometrical designs of the amalgamated layers, engineering characteristics of the materials, and the interaction of both on the ballistic resistance of the transparent armor. The resulted models are used to analyze the strength feasibility of the material in the cost base. Ballistic measurements over a wide range of impact velocities including those well above the ballistic limits are deployed to the model. Under simple loading conditions, the polycarbonate matrix glass or ceramic can be regarded as elastic-brittle materials, however, when considering ballistic impacts the post-yield response of the ceramic becomes significant. A post-yield response model of ceramic materials is used for simulating the characteristics. The model incorporates the effect of damage on residual material strength and the resulting bulking during the compressive failure of the ceramic. A combination of relevant factors including the ability to dissipate ballistic energy and manufacturing processes was considered for the proper evaluation and selection of the armor. The model has been implemented into computer software to predict unsuccessful solutions and optimize the amalgamation with capabilities of defeating a wider range of ballistic impacts. The results will show more physical insight of the behavior and performance of the complex armor systems and provide guidelines/principles for the design and selection of the constituent materials.

The Design of a Small Satellite for Earth Observation

1996 ◽  
Vol 210 (4) ◽  
pp. 323-332 ◽  
Author(s):  
S J Gardner ◽  
G G Swinerd ◽  
A K Ward
Keyword(s):  
Low Cost ◽  
Earth Observation ◽  
Low Earth Orbit ◽  
Small Satellite ◽  
Satellite Design ◽  
The Earth ◽  
Wide Range ◽  
Low Mass ◽  
Available Technology ◽  
Selection Of

The concept of the Teaching Company Scheme Satellite (TuCSAT), has been developed to meet the requirements of the Earth observation user community for inexpensive and flexible opportunities to launch remote sensing instruments into low earth orbit (LEO). This paper describes the satellite design process, together with the philosophy behind the selection of a baseline mission. The satellite is shown to demonstrate the ability to meet a wide range of requirements within a strict low mass and low cost philosophy, while making use of currently available technology in order to achieve the design aims.

scholarly journals Surface texturing of non-toxic, biocompatible titanium alloys via electro-discharge

2021 ◽  
Vol 2 (1) ◽  
pp. 51-56
Author(s):  
Ajaytaj Singh Sidhu ◽  
Keyword(s):  
Low Cost ◽  
Surface Texturing ◽  
Tool Material ◽  
Dielectric Medium ◽  
Tool Electrode ◽  
Ti Alloy ◽  
Wide Range ◽  
Current Article ◽  
High Degree ◽  
Selection Of

The developments of Al and V free, biocompatible Ti-alloy have been the subject of researcher in the orthopedic joints replacement domain. The current article addresses the methodology chosen for Ti-alloy design, machinability, and low-cost surface texturing process for a high degree of biocompatibility. It is evident that an astonishing increase in biocompatibility can be achieved by synchronizing electro-discharge spark energy within Ti alloy and tool material coupled with the selection of dielectric medium for surface modification. The finding of this research may benefit a wide range of researchers to design sustainable implants. The positive polarity tool electrode at 10 A is the most desirable process parameter developing the bioactive surface.

COMBINATORIAL POLYNOMIALLY COMPUTABLE CHARACTERISTICS OF SUBSTITUTIONS AND THEIR PROPERTIES

2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  
Keyword(s):  
Mathematical Expectation ◽  
Point Of View ◽  
Small Range ◽  
Computational Point ◽  
Wide Range ◽  
Bijective Function ◽  
The Difference ◽  
Element Base ◽  
Selection Of

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.

Synthesis, Characterization and Antiproliferative Activity Assessment of a Novel 1H-5-mercapto-1,2,4 Triazole Derivative

2017 ◽  
Vol 68 (4) ◽  
pp. 745-747 ◽  
Author(s):  
Marius Mioc ◽  
Sorin Avram ◽  
Vasile Bercean ◽  
Mihaela Balan Porcarasu ◽  
Codruta Soica ◽  
...  
Keyword(s):  
Antiproliferative Activity ◽  
Biological Activities ◽  
Cancer Cell Line ◽  
Vascular Endothelial ◽  
Triazole Derivative ◽  
Activity Assessment ◽  
Wide Range ◽  
Specific Receptors ◽  
Endothelial Growth Factor ◽  
Selection Of

Angiogenesis plays an important function in tumor proliferation, one of the main angiogenic promoters being the vascular endothelial growth factor (VEGF) which activates specific receptors, particularly VEGFR-2. Thus, VEGFR-2 has become an essential therapeutic target in the development of new antitumor drugs. 1,2,4-triazoles show a wide range of biological activities, including antitumor effect, which was documented by numerous reports. In the current study the selection of 5-mercapto-1,2,4-triazole structure (1H-3-styryl-5-benzylidenehydrazino-carbonyl-methylsulfanil-1,2,4-triazole, Tz3a.7) was conducted based on molecular docking that emphasized it as suitable ligand for VEGFR-2 and EGFR1 receptors. Compound Tz3a.7 was synthesized and physicochemically and biologically evaluated thus revealing a moderate antiproliferative activity against breast cancer cell line MDA-MB-231.

Sign in / Sign up

Export Citation Format

Share Document