The challenge in detecting explosive hazards is that there are multiple types of targets buried at different depths in a highlycluttered
environment. A wide array of target and clutter signatures exist, which makes detection algorithm design difficult.
Such explosive hazards are typically deployed in past and present war zones and they pose a grave threat to the safety of
civilians and soldiers alike. This paper focuses on a new image enhancement technique for hand-held ground penetrating
radar (GPR). Advantages of the proposed technique is it runs in real-time and it does not require the radar to remain at a
constant distance from the ground. Herein, we evaluate the performance of the proposed technique using data collected
from a U.S. Army test site, which includes targets with varying amounts of metal content, placement depths, clutter and
times of day. Receiver operating characteristic (ROC) curve-based results are presented for the detection of shallow,
medium and deeply buried targets. Preliminary results are very encouraging and they demonstrate the usefulness of the
proposed filtering technique.
Glyphosate based herbicide programs are most preferred in current row crop weed control practices. With the increased
use of glyphosate, weeds, including Italian ryegrass (Lolium multiflorum), have developed resistance to glyphosate. The
identification of glyphosate resistant weeds in crop fields is critical because they must be controlled before they reduce
the crop yield. Conventionally, the method for the identification with whole plant or leaf segment/disc shikimate assays
is tedious and labor-intensive. In this research, we investigated the use of high spatial resolution hyperspectral imagery to
extract spectral curves derived from the whole plant of Italian ryegrass to determine if the plant is glyphosate resistant
(GR) or glyphosate sensitive (GS), which provides a way for rapid, non-contact measurement for differentiation between
GR and GS weeds for effective site-specific weed management. The data set consists of 226 greenhouse grown plants
(119 GR, 107 GS), which were imaged at three and four weeks after emergence. In image preprocessing, the spectral
curves are normalized to remove lighting artifacts caused by height variation in the plants. In image analysis, a subset of
hyperspectral bands is chosen using a forward selection algorithm to optimize the area under the receiver operating
characteristic (ROC) between GR and GS plants. Then, the dimensionality of selected bands is reduced using linear
discriminant analysis (LDA). Finally, the maximum likelihood classification was conducted for plant sample
differentiation. The results show that the overall classification accuracy is between 75% and 80% depending on the age
of the plants. Further refinement of the described methodology is needed to correlate better with plant age.
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