Author details

communication cable (bidirectional with a maximum baud speed up to 115,200 bites per seconds) for transferring and storing collected data in PC. All vital components (i.e., clock generator, 2 KB of RAM, 32 KB of flash memory for storing programs and 1 KB of EEPROM for storing parameters, a 16-MHz crystal oscillator, digital input/output pins, USB connection, power regulator, power jack, and a reset button) for operating the microcontroller, as well as direct programming and access to input/output pins, were available on the prototype board. Four arrays of HSM-20G-combined sensors modules (Shenzhen Mingjiada Electronics LTD, Futian Shenzhen, China), external micro-secure digital (SD) cardboard for storing larger amount of sensor data, output connection, sensor input, and relay circuit board for on/off control purposes were used. The data acquisition interface was tested for accuracy and reliability with available commercial models, and with a control sample data collected from

<sup>K</sup> :ln ð Þ <sup>1</sup> � <sup>m</sup> :LFmax <sup>þ</sup> Qeð Þ <sup>T</sup> : <sup>K</sup>: PPFD

� �

dt <sup>¼</sup> <sup>0</sup> : LAI <sup>≥</sup> LAImax

� � :

� �:g Tdaytime

N

i¼1

α:dα �

1 þ exp β:ð Þ N � Nb

� � <sup>¼</sup> max 0:09, min 1, <sup>1</sup> � <sup>0</sup>:<sup>154</sup> Tdaytime � Tcrit

Cf tð Þ <sup>M</sup>, t, <sup>α</sup> :d<sup>α</sup> <sup>¼</sup> <sup>X</sup>

0 @

<sup>α</sup><sup>¼</sup>ð<sup>α</sup><sup>s</sup>

α¼0

The financial support provided by the University of Putra Malaysia, Grant Number GP-IPB/ 2013/9415600, and the scientific comments and suggestions from Professor Warren Dixon, Professor Jim Jones, and Professor Ray Bucklin at the University of Florida, and Professor Jan

Bontsema at the Wageningen University and Research Center are duly acknowledged.

ð Þ 1 � m : LFmax þ Qeð Þ T : K: PPFD : expð Þ �k : LAI � �

� � � � � � (4)

Optð Þ M :dα

dt <sup>¼</sup> DFð Þ Td :ð Þ WF � WM , if N <sup>&</sup>gt; NFF <sup>þ</sup> <sup>κ</sup><sup>F</sup> (5)

<sup>α</sup><sup>¼</sup>ð<sup>α</sup><sup>s</sup>

α¼0

dt : LAI <sup>≤</sup> LAImax

� � if N > NFF (3)

Cf tð Þ� M, t, α<sup>i</sup> α<sup>i</sup> (6)

A (7)

1

dN

(1)

(2)

airport weather station at Sultan Abdul Aziz Shah-Subang in Malaysia.

dt <sup>¼</sup> <sup>ρ</sup>:δ:λð Þ Td : exp <sup>β</sup>:ð Þ <sup>N</sup> � Nb

dt <sup>¼</sup> GRnet:αF:<sup>f</sup> <sup>F</sup>ð Þ Td : <sup>1</sup> � exp ð Þ �ϑð Þ <sup>N</sup> � NFF

Ph <sup>¼</sup> <sup>D</sup> : LFmax : PGRED Tð Þ

d LAI ð Þ

8 >>><

188 Plant Engineering

>>>:

dWF

Acknowledgements

d LAI ð Þ

g Tdaytime

dWM

<sup>α</sup><sup>¼</sup>ð<sup>α</sup><sup>s</sup>

α¼0

ADPðM, αsÞ ¼ 1 � 2

α<sup>y</sup> ¼

Redmond R. Shamshiri1,2\*, Muhammad Razif Mahadi2 , Kelly R. Thorp<sup>3</sup> , Wan Ishak Wan Ismail<sup>2</sup> , Desa Ahmad<sup>2</sup> and Hasfalina Che Man<sup>2</sup>

\*Address all correspondence to: Redmond@AdaptiveAgroTech.com

1 Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL, USA

2 Department of Biological and Agricultural Engineering, Faculty of Engineering, Universiti Putra Malaysia, Serdang, Selangor, Malaysia

3 United States Department of Agriculture, Agricultural Research Service, Maricopa, AZ, USA
