ICAR AICE-JRF/SRF (PhD) — Agricultural Engineering subjects 38–43 · India · National Testing Agency for ICAR
Original practice questions written to the published syllabus · not past papersUsing positioning, sensing and variable-rate control to manage fields by the metre instead of by the hectare.
In the exams: ICAR AICE subject 43 Unit 8; elective in the ICAR 6th Deans' Committee B.Tech
ICAR AICE-JRF/SRF (PhD) — Irrigation and Drainage Engineering (subject 43, Unit 8)
Definitions and components of precision agriculture; GNSS principles and accuracy classes; vegetation indices, especially NDVI; variable-rate irrigation and fertigation; soil sensing and management zones; recall of standards such as ISO 11783.
How our questions for ICAR AICE-JRF/SRF spread across the units of Precision Agriculture & System Management. Difficulty: 24 easy, 30 medium, 17 hard.
| GNSS and RTK positioning | 13 | |
| Proximal and remote sensing for crops | 12 | |
| Prescription maps | 10 | |
| Yield monitoring | 7 | |
| Variable-rate technology | 7 | |
| ISOBUS basics | 6 | |
| Farm management information systems | 6 | |
| Auto-steer and guidance | 4 | |
| Farm data management | 4 | |
| Section control | 2 |
Choose an answer, then open the working. Each explanation says why the right answer is right and why the others are not.
Which of these is a regional satellite navigation system rather than a global one?
D. NavIC
NavIC (IRNSS) covers India and the surrounding region. GPS, GLONASS, Galileo and BeiDou are the four global constellations.
A GNSS receiver has a user equivalent range error of 5 m and the horizontal dilution of precision is 1.2. The expected horizontal position error is about
D. 6.0 m
Position error ≈ UERE × DOP = 5 × 1.2 = 6.0 m. Dividing (5/1.2 = 4.2 m) or adding (5 + 1.2 = 6.2 m) are the usual slips, and 0.24 m inverts the ratio (1.2/5); DOP multiplies the range error.
What distinguishes real-time kinematic (RTK) positioning from ordinary code-based GNSS?
C. It resolves carrier-phase ambiguities using data from a nearby base station
RTK uses the carrier phase and corrections from a base at a known point to fix integer ambiguities, giving about 1–2.5 cm. Wide-area geostationary corrections describe SBAS, which gives sub-metre accuracy; averaging code ranges or using Doppler does not reach centimetre level.
A semivariogram of soil P has a range of 120 m. A common rule of thumb gives a maximum grid sampling interval of about
A. 60 m
Sampling at less than half the range keeps neighbours correlated: 120 / 2 = 60 m. Sampling at the range (120 m) or twice it (240 m) leaves points uncorrelated; 30 m is safe but not the maximum.
When choosing the number of management zones with fuzzy c-means, the fuzziness performance index (FPI) and normalised classification entropy (NCE) are used. Which number is preferred?
C. The number at which both indices are at or near their minimum
Low FPI and NCE mean less membership sharing and more distinct classes, so the minimum indicates the best number, moderated by practical judgement (typically 2–5 zones). More zones are not better if they cannot be managed.
A canopy has NIR reflectance 0.50 and red reflectance 0.08. Its NDVI is about
A. 0.72
NDVI = (0.50 − 0.08)/(0.50 + 0.08) = 0.42/0.58 = 0.72. 0.42 forgets the denominator; 6.25 is the simple ratio NIR/red; 0.84 is 0.42/0.50.
Which part of ISO 11783 defines the virtual terminal, which lets one cab display operate implements from different makers?
A. Part 6
Part 6 is the virtual terminal. Part 10 is the task controller, Part 9 the tractor ECU and Part 2 the physical layer.
An ISOBUS message longer than 8 data bytes is sent using the transport protocol. The largest message this protocol can carry is
D. 1785 bytes
The transport protocol splits data into packets of 7 bytes with a maximum of 255 packets: 255 × 7 = 1785 bytes. 2040 uses 8 bytes per packet; 255 is the packet count; larger transfers use the extended transport protocol. 1792 bytes uses 256 packets instead of 255.
At 250 kbit/s, the duration of one bit on the ISOBUS network is
D. 4 µs
Bit time = 1 / 250,000 s = 4 × 10⁻⁶ s = 4 µs. 0.4 and 40 µs are decimal slips; 250 µs confuses rate with time.
Which decision-support function is commonly built into a modern FMIS?
B. Irrigation scheduling from a soil-water balance
FMIS decision-support modules include irrigation scheduling, disease-risk forecasts and crop models. Bus settings, firmware and machine design are not FMIS functions.
Ten here, 71 in the app. The Laisha app has every practice question we have written to ICAR AICE-JRF/SRF in this subject, marked as you go, with timed papers, a jump-to-unanswered list and a certificate when you pass at 70 per cent.
Free for ten days, then one subscription of US$10 a month. We would rather say so here than have you find it later.
An AI operating system for agriculture: free guides, manuals and tools written for every country.