The Use of Gas-Sensor Arrays in the Detection of Bole and Root Decays in Living Trees

198 Pages·2015·13.71 MB·English

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Volume 193 www.sensorsportal.com ISSN 2306-8515
Issue 10 e-ISSN 1726-5479
October 2015

Research Articles

Smart and Customized Electrical Conductivity Sensorfor Measurements
of the Response Time from SprayersBased on Direct Injection
Heitor V. Mercaldi, Caio H. Fujiwara,Elmer A. G. Peñaloza, Vilma A. Oliveira,
Paulo E. Cruvinel ............................................................................................................... 1

Dynamical Capillary Rise Photonic Sensor for Testing of Diesel
and Biodiesel Fuel
Michal Borecki, Michael L. Korwin-Pawlowski, Mariusz Duk, Andrzej Kociubiński,
Jarosław Frydrych, Przemyslaw Prus, Jan Szmidt ............................................................ 11

Novel Smart Glove Technology as a Biomechanical Monitoring Tool
Brendan O’Flynn, J. T. Sanchez, S. Tedesco, B. Downes, J. Connolly, J. Condell,
K. Curran ............................................................................................................................ 23

Wide Spectral Sensitivity of Monolithic a-SiC:H pi’n/pin Photodiode Outside
the Visible Spectrum
Manuela Vieira, Manuel Augusto Vieira, Isabel Rodrigues,Vitor Silva, Paula Louro,
A. Fantoni ........................................................................................................................... 33

Sub-nanosecond Gating of Large CMOS Imagers
Octavian Maciu, Wilfried Uhring, Jean-Pierre Le Normand, Jean-Baptiste Kammerer,
Foudil Dadouche, Norbert Dumas ...................................................................................... 41

Superpixel Compressive Sensing Recovery of Spectral Images Sensed
by Multi-patterned Focal Plane Array Detectors
Yuri H. Mejia, Fernando A. Rojas, Henry Arguello ............................................................. 50

Advanced Controlled Cryogenic Ablation Using Ultrasonic Sensing System
Assaf Sharon, Gabor Kosa ................................................................................................ 57

Cavity Enhanced Absorption Spectroscopy in Air Pollution Monitoring
Janusz Mikołajczyk, Zbigniew Bielecki, Jacek Wojta, Sand Sylwester Chojnowski .......... 63

Design and Analysis of a Collision Detector for Hybrid Robotic Machine Tools
Dan Zhang, Bin Wei ........................................................................................................... 67

Numerical Signal Analysis of Thermo-Cyclically Operated MOG Gas Sensor
Arrays for Early Identification of Emissions from Overloaded Electric Cables
Rolf Seifert, Hubert B. Keller, Navas Illyaskutty, Jens Knoblauch and Heinz Kohler ........ 74

Analysis of the Planar Electrode Morphology Applied to Zeolite Based
Chemical Sensors
Luiz Eduardo Bento Ribeiro, Glaucio Pedro de Alcântara, Cid Marcos Gonçalves
Andrade, Fabiano Fruett .................................................................................................... 80
An Empirical Study for Quantification of Carcinogenic Formaldehyde
by Integrating a Probabilistic Framework with Spike Latency Patterns
in an Electronic Nose
Muhammad Hassan, Amine Bermak, Amine Ait Si Ali and Abbes Amira .......................... 86

Alternative Processes for Manufacturing of Metal Oxide-based
Potentiometric Chemosensors
Winfried Vonau, Manfred Decker, Jens Zosel, Kristina Ahlborn, Frank Gerlach,
David Haldan and Steffen Weissmantel ........................................................................... 93

Improvement in Humidity Sensing of Graphene Oxide by Amide
Functionalization
Sumita Rani, Dinesh Kumar, Mukesh Kumar .................................................................... 100

PbS Infrared Detectors: Experiment and Simulation
S. Kouissa, A. Djemel, M. S. Aida, M. A. Djouadi .............................................................. 106

Amplitude to Phase Conversion Based on Analog Arcsine Synthesis
for Sine-cosine Position Sensors
Mohieddine Benammar, Antonio Jr. Gonzales .................................................................. 114

New Design-methodology of High-performance TDC on a Low Cost
FPGA Targets
Foudil Dadouche, Timothé Turko, Wilfried Uhring, Imane Malass, Norbert Dumas,
Jean-Pierre Le Normand .................................................................................................... 123

Experiences in Automation and Control in Engineering Education with Real-
world Based Educational Kits
Filomena Soares, Celina Pinto Leão,José Machado and Vítor Carvalho .......................... 135

Improving Systems Dynamics by Means of Advanced Signal Processing –
Mathematical, Laboratorial and Clinical Evaluation of Propofol Monitoring
in Breathing Gas
Dammon Ziaian, Philipp Rostalski, Astrid Ellen Berggreen, Sebastian Brandt,
Martin Grossherr, Hartmut Gehring, Andreas Hengstenberg and Stefan Zimmermann ... 145

The Use of Gas-Sensor Arrays in the Detection of Bole and Root Decays
in Living Trees: Development of a New Non-invasive Method of Sampling
and Analysis
Manuela Baietto, Sofia Aquaro, A. Dan Wilson, Letizia Pozzi, Daniele Bassi ................... 154

Motor Bourn Magnetic Noise Filtering for Magnetometers
in Micro-Rotary Aerial Vehicles
Nathan J. Unwin, Adam J. Postula..................................................................................... 161

Reflection from Disordered Silver Nanoparticles on Multilayer Substrate
Victor Ovchinnikov ............................................................................................................. 170

Performance Analysis of Commercial Accelerometers: A Parameter Review
Stephan Elies ..................................................................................................................... 179

Authors are encouraged to submit article in MS Word (doc) and Acrobat (pdf) formats
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Sensors & Transducers, Vol. 193, Issue 10, October 2015, pp. 1-10
Sensors & Transducers
© 2015 by IFSA Publishing, S. L.

http://www.sensorsportal.com

Smart and Customized Electrical Conductivity Sensor
for Measurements of the Response Time from Sprayers
Based on Direct Injection

1, 2 Heitor V. MERCALDI, 1, 2 Caio H. FUJIWARA,
1, 2 Elmer A. G. PEÑALOZA, 2 Vilma A. OLIVEIRA,
1 Paulo E. CRUVINEL
1 Embrapa Instrumentação, Rua XV de Novembro 1452, São Carlos, SP, 13560-970, Brazil
2 Universidade de São Paulo, Av. Trabalhador Sãocarlense 400, São Carlos, SP, 13566-590, Brazil
1 Tel.: [phone], fax: [phone]
1 E-mail: [email protected]

Received: 31 August 2015 /Accepted: 5 October 2015 /Published: 30 October 2015

Abstract: In the application of herbicides on the basis of direct injection systems, spraying response time plays
an important role for the quality of spraying, particularly when operating in real time. The response time is
defined as the time elapsed from the time of injection until the concentration of the mixture (water mixed with
herbicide) reaches 95 % of its regime value in the sprayer nozzles. In the response time, the transport delay and
the rise time for achieving the desired concentration are considered. This paper describes an intelligent sensor
mounted near the sprayer nozzles to measure the concentration response time in an herbicide direct injection
system, which uses a highly stable sinusoidal excitation signal. The sensor calibration was performed with NaCl
solutions at concentrations similar to those found in actual application conditions. Using an integrated system
based on the Arduino platform, an algorithm was developed to relate the measurements to the response time.
The integrated system comprises the sensor with its own sensing hardware, A/D converter, processing and
storage capabilities, software drivers, self-assessment algorithms and communication protocols. The immediate
application of the integrated system is in the monitoring of the response time of a precision herbicide
application. The results point to the next generation of smart devices that have embedded intelligence to support
decision making in precision agriculture. Copyright © 2015 IFSA Publishing, S. L.

Keywords: Intelligent sensor, Electrical conductivity, Direct injection, Response time.

1. Introduction is still rising up according to data from the Brazilian
National Union of the Industry of Agricultural
Brazil has experienced in the last two decades a Defense Products [1], association which represents
significant increase in the use of pesticides for the pesticide manufacturers in the country.
agricultural production. Despite the significant In In the same period, the cultivated area with
growth of the area cultivated with transgenic seeds, a grains, fiber, coffee and sugar cane grew by less than
technology that promises to reduce chemical use in 19 %, from 68.8 million to 81.7 million hectares,
agricultural production, sales of these products according to the Brazilian National Company for
increased by over 72 % between 2006 and 2012 and Supply [2]. This means that the average consumption
http:// www.sensorsportal.com/HTML/DIGEST/P_2729.htm 1
Sensors & Transducers, Vol. 193, Issue 10, October 2015, pp. 1-10
of pesticides, which was just over 7 kilograms per perform on-line changes in the concentration [22].
hectare in 2005, rose to 10.1 kilograms in 2011, an The direct injection systems advantage is in the
increase of 43.2 %. Although this amount mixing of the required amount of chemicals with
indicates more protection for products and higher water, saving the excess amount for later use [23]. A
incomes, the uniform rate of application leads key indicator to determine the precision of a direct
to soil and water contamination. A key approach to injection sprayer is the control system response time.
reduce environmental pollution is to use For sprayers, how much shorter the response time,
variable-rate application. much higher will be its field precision.
An approach to develop variable-rate sprayer This paper presents the complete version of a
technologies is to install automation and control smart and customized conductivity sensor (SCCS) for
procedures in conventional sprayers. In order to the evaluation of the response time of direct injection
adjust the sprayer operation, reference for variables sprayers based on the electrical conductivity
such as working pressures, travelling speeds, and measurements. Previous discussions related to its
spraying concentration rates can be selected to development were presented in [24], and [25]. With
achieve uniform drop size distribution. the response time measurements in variable rate
The agricultural machinery and technologies sprayers, a looking-ahead approach, which is useful
available today allow chemical application variable to increase competitiveness and support sustainability
rate based on prescription maps or sensors [3]. in agriculture can be performed.
Variable-rate application can be performed by After this introduction, this paper is organized as
varying the concentration of the chemical on-the-go follows. Section 2 presents the theoretical
using a direct injection system [4]. The direct background on electrical conductivity; Section 3
injection system is an electronically controlled presents the materials and methods for the
system in which the chemical is injected into the development of the SCCS and the procedures for its
carrier stream. The direct injection system has validation. Finally, the results and discussions are
separated chemical and carrier reservoirs and the presented in Section 4, followed by the conclusion
chemical can be injected into the carrier stream in in Section 5.
different positions.
In the literature, reports of systems to inject
concentrated pesticides into the carrier stream began 2. Theoretical Background
to appear in the 70th decade [5]. In [6], Vidrine and
collaborators tested the feasibility of injecting The electrical conductivity, also called specific
concentrated pesticides. In [7], Reichard and Ladd conductance, is the ability of a solution to conduct an
developed a field sprayer which included injection of electric current. The mechanism for the electrical
pesticides at specific rates accounting for variations current conduction in electrolyte solutions is not the
in travel speed. In [8], Chi and collaborators same as for metals. In liquids, this process is based
developed a flow rate control system which allowed on the movement of solvated ions, which are
the measurements of concentrated pesticides. In [9], attracted by an electrical field. Therefore, the
Ghate and Perry developed a field sprayer based on physical-chemical process is related to the occurrence
the use of a compressed air to inject chemical into the of combination between the molecules of a solvent
carrier stream. In [10], Miller and Smith reported the with molecules or ions of the dissolved substance. As
development of a direct injection system. In general, electrolyte solutions obey Ohm’s law in the same
during the spraying process errors can be observed. way as the metallic conductors, when powered by
Research works on the evaluation of the application direct current passing through the body of the
rate errors have shown that errors are not only due to solution, the conductance denoted G is defined as the
the deviations from the target flow rates but also due inverse of the resistance expressed in Ω−1or Siemens
to interaction between the dynamics of the systems (S). The conductance G of a homogeneous body
and sprayer response time. By now, is quite well having uniform section is proportional to the cross-
known that the direct injection system sprayer sectional area of the conductor A and inversely
response time depends on the sprayer dynamics and proportional to the length of the conductor denoted
on the transport delay [11]. by l, that is:
The transport delay is due to flow rates and
distance of the nozzle from the injection point. The G=σA, (1)
farther from the injection point the nozzle is, the 
larger the uniformity of the mixture, but the higher
the transport delay of the sprayer. Several studies on where the proportionality constant σ is the electrical
the performance of direct injection sprayers and the conductivity given in S/m. The ratio l /A is called the
response time have appeared [12-20]. Therefore, the conductivity cell constant and depends on the
conventional implements can be reorganized to instrumentation used. The conductivity increases
operate in variable-rate using control systems [21]. with increasing temperature. Furthermore, the
An advantage of the injection rate application conductivity of a solution depends on the number of
over pressure-based variable rate application is the ions present and for this reason the most common is
ability to change the herbicide type as well as to the use of the molar conductivity defined as:
2
Sensors & Transducers, Vol. 193, Issue 10, October 2015, pp. 1-10
Λ = σ, (2) Thus, turning the unit concentration mol/L to
m M mol/cm3, the equivalent conductivity Λ between two
m
electrodes spaced 1 cm away due to 1 mol of
where Λm is the equivalent conductivity or the molar substance may be given as:
conductivity in Sm2/mol and M is the molarity or
mcoonldaur ctivciotyn cevnatrriaetsi onw ithi nt he mcooln/Lce. ntraTthioen omf otlhaer Λ =1000σcorrected (5)
m M
electrolytes. The main reason for this effect is the

change in the number or mobility of the ions present.
Then, for a parallel plate sensor, the conductance
The first case occurs in weak electrolytes, where the
G can be determined based on the molar conductivity
dissociation of ions in a solution is not complete. The
second case occurs on strong electrolytes, where in Λm. The corrected specific conductivity of the
the solution the dissociation of the molecule into ions electrolyte is then given in terms of the total ionic
is total, resulting in a very strong interaction between concentration M (mol/cm3) of the substance in the
the oppositely charged ions, and can reduce electrolyte solution and the equivalent conductivity.
its mobility. Therefore, by using the Equation (1), the conductance
The measurements of electrical conduction in G can be found as:
ionic solutions are useful for a quick and routine
arenlaaltyesdi s too f thsoel uptiroonpse,r tsieinsc eo fi t thise as osliumtipolne . mInea stuhries G(A,,Λm,M)=Λ10m0M0 ×A (6)
context, the conductivity of a solution in a cell having
an arbitrary dimension can be obtained by measuring
Peck and Roth defined response time (t ) as the
T
the resistance of a solution of known concentration to
period from the instant the injection begins until the
determine the cell constant. After the cell constant is
chemical concentration rate reaches 95 % of the
determined, the values of conductivities of different
equilibrium rate [27]. The rise time (t) and
r
solutions can be obtained from experimental
transport delay (t ) characteristics of a sprayer
d
measurements data. For devices without automatic
proposed by these authors are shown in Fig. 1.
temperature compensation, the conductivity must be
A 95 % concentration rate corresponds to the
determined at the reference temperature.
chemical concentration of the spraying, which is
The measurement of absolute values of
necessary for satisfactory weed control [28].
conductivity requires the use of linear temperature

compensation. Therefore, an electrical conductivity

measured at room temperature can be corrected to
one reference temperature, such per example, 25°C
as follows:

G
G = ( θ)( ), (3)
25 1+ α100 θ−25

where θ is the room temperature, Gθ is the
conductivity measured at room temperature and α is
the temperature coefficient of variation in %/°C.
Typical values for temperature coefficients are given
in Table 1 [26].

Table 1. Typical temperature coefficients of substances. Fig. 1. Delay time (td), rise time (tr), and response time (tT)
of a typical injection system as described in [27]. The

dotted line indicates the time behavior of the concentrated
Substance α (%/°C) mixture (water-NaCl) as a response to an injection input.
Acids 1.0 to 1.6

Bases 1.8 to 2.2
Salts 2.2 to 3.0
Potable water around 2.0 The response illustrated in Fig. 1 can be identified
as a first order system plus delay time. The time

response is given by:
In solutions, yet it is necessary to correct the

conductivity observed by subtracting the conductivity
T =T +3T , (7)
of the solvent, to get the value of σ . Therefore, r d c
corrected
the molar conductivity Λ shall be written as:
m
where 3T is the requested time to reach 95 % in
c
σ concentration in relation of the steady state value,
Λ = corrected (4) i.e., after T seconds [29].
m M d

3