New technologies are utilized to improve forest management, but they require the collection and analysis of digital data. This study assessed the applicability of using light detection and ranging ...(LiDAR) devices for the examination of forest resource inventories to obtain digital forest resource information. Two terrestrial LiDARs, a backpack laser scanner (BPLS) and a terrestrial laser scanner (TLS) were used and compared with the traditional method to identify which was optimal. The findings showed that the TLS single-scan method was least accurate due to occlusion. The TLS multi-scan method and the BPLS showed high levels of accuracy for the height and diameter at breast height (DBH) estimates in most sample plots. However, the BPLS underestimated height to a greater extent than the other methods in a sloped plot (24°). Nevertheless, the efficiency of the BPLS was 2.8 times higher than that of the TLS when considering the amount of time spent on completing all indoor and outdoor tasks. Thus, these results prove that the utilization of LiDAR devices increases the efficiency of data collection and overcomes the limitations of existing methods. Moreover, they provide accurate information that will be a basis for forest management plans, the estimation of biomass, and the transaction of forest products.
A new non-cyst forming nematode,
n. sp., was found from the root of crapemyrtle (
) in Korea. Female
n. sp. appears pearly white when young, has protruding vulval lips, flat to concave anus-vulva ...profile and has three lateral lines in J2s. Morphologically,
n. sp. is most similar to
but differ by the tail shape of J2 (sharply pointing with constriction at the middle of hyaline without mucro tip vs. sharply pointing with mucro-like tip), shorter stylet length of J2 (26.8–31.3 µm vs 31.6–35.4 µm), stylet knob shape of J2 (flat posteriorly vs concave), number of eggs in female (64–69 vs 15–45).
n. sp. differs from
by the longer vulva-anus distance (51.9–54.1 µm vs 35 µm), the bigger body size of female (363.1–544.6 µm vs 272–353 µm in length), in J2, the longer tail length (59.6–76.7 µm vs 27–54 µm), longer hyaline length (31.7–47.8 µm vs 18–26 µm) and the shape of tail (sharply pointing with constriction at the middle of hyaline vs narrow rounded without constriction). From
, the new species differs by the longer J2 tail length (59.6–76.7 µm vs 52.0–65.0 µm) and longer hyaline portion (31.7–47.8 µm vs 24.5–35.0 µm) of J2.
n. sp. and can be distinguished from the remaining four species,
,
,
and
, by the shape of the J2 tail terminus (sharply pointing tip with constriction at the middle of hyaline vs narrow rounded) and the shape of the vulval lips (pronounced protruding vs protruding slightly out of body contour). Molecular analysis shows that
n. sp. is the most similar to
with the identity of sequence 95% on the rRNA LSU D2–D3 segments and the highest match with
with 88% identity on the ITS region.
Anew soybean cyst nematode
n. sp. was found from the roots of soybean plants in Korea. Cysts of
n. sp. appeared more round, shining, and darker than that of
. Morphologically,
n. sp. differed from
by ...fenestra length (23.5–54.2 μm vs. 30–70 μm),vulval silt length (9.0–24.4 μm vs. 43–60 μm), tail length of J2 (54.3–74.8 μm vs. 40–61 μm),and hyaline part of J2 (32.6–46.3 μm vs. 20–30 μm). It is distinguished from
by larger cyst (513.4–778.3 μm × 343.4– 567.1 μm vs. 350–560 μm × 250– 450 μm) and longer stylet length of J2 (23.8–25.3 μm vs. 17–19 μm). Molecular analysis of rRNA large subunit (LSU) D2–D3 segments and ITS gene sequence shows that
n. sp. is more close to rice cyst nematode
than
n.sp. was widely distributed in Korea. It was found from soybean fields of all three provinces sampled.
The objective of this study is to monitor the water content of soil quickly and accurately using a UAV. Because UAVs have higher spatial and temporal resolution than satellites, they are currently ...becoming more useful in remote sensing areas. We developed a water content estimation equation using the color of the soil and suggested a calibration method for field application. Since the resolution of the images taken by the UAV is different according to the altitude, the water content estimation formula is developed by using the images taken at each altitude. In order to calibrate the color difference according to lighting conditions, the calibration method using field data were proposed. The results of the study showed an altitude-specific estimation equation using RGB values of the UAV image through linear regression. The appropriate number of field data needed for calibration for site application of the estimation equation was found between 4 and 10. On-site application results of the proposed calibration method showed RMSE accuracy of 1.8 to 2.9%. Thus, the water content estimation and calibration method proposed in this study can be used in effectively monitoring the water content of soil using UAVs.
Digital image processing (DIP) is used to measure shape properties and settling velocity of soil particles. Particles with diameters of 1 to 10 mm are arbitrarily sampled for the test. The size of ...each particle is also measured by a Vernier caliper for comparison with the classification results using the shape classification table. The digital images were taken with a digital camera (Canon EOS 100d). Shape properties are calculated by image analysis software. Settling velocity of soil particles is calculated by displacement and time difference of images during settling. The fastest settling particles are spherical shaped. Shape factors well explain the difference of settling velocity by a particle shape. In particular, the aspect ratio has a high negative correlation with residual of settling velocity versus mean diameter. Especially, DIP has a higher applicability than classification using the shape classification table because it can measure a number of particles at once. The settling velocity of soil particles is expressed as a function of mean diameter and aspect ratio.
Morphological (cyst shape, color, and sizes length (L), maximum width (W), volume and "a" (L/W)), structural (vulvar cone slope angle VCSA, surface wrinkle VCSW, cyst wall thickness, composition, and ...texture) and biological characteristics (fecundity, hatching, and emergence number of second-stage juveniles (J2) from a cyst) in preceding
(Hg), currently-recorded
(Hs) and
(Ht) were examined by microscopy. Cysts were lemon-shaped, indicating the genus is
except for Hs that formed frequently globular cysts with significantly flatter VCSA (102.2°) with smooth VCSW than Hg (50.6°) and Ht (82.0°), but not genus
because of the presence of vulvar cone in Hs. Ht was significantly larger in all morphological characteristics than Hg and Hs, suggesting Ht may be diagnosed differentially by cyst sizes and also host plant preferences. Hs showed smaller "a" value with more globular shape and stronger structures with more thickened and strengthened collagen-like texture of cyst wall than Hg and Ht. This suggests Hs may be diagnosed differently by structural characteristics from the others, especially Hg with similar cyst sizes. There were no significant differences in emergence (inoculum potential) among cyst nematodes due to the offset of fecundity and hatching rate; however, the inoculum potential of Hs may be not so persistent as Hg and Ht in fields because of its lower fecundity and higher hatching rate (causing rapid inoculum loss) than the others. These characteristics of cysts provide information useful for simple and differential diagnoses and reliable management of cyst nematodes.
Morphological (cyst shape, color, and sizes length (L), maximum width (W), volume and "a" (L/W)), structural (vulvar cone slope angle VCSA, surface wrinkle VCSW, cyst wall thickness, composition, and ...texture) and biological characteristics (fecundity, hatching, and emergence number of second-stage juveniles (J2) from a cyst) in preceding Heterodera glycines (Hg), currently-recorded H. sojae (Hs) and H. trifolii (Ht) were examined by microscopy. Cysts were lemon-shaped, indicating the genus is Heterodera except for Hs that formed frequently globular cysts with significantly flatter VCSA (102.2°) with smooth VCSW than Hg (50.6°) and Ht (82.0°), but not genus Globodera because of the presence of vulvar cone in Hs. Ht was significantly larger in all morphological characteristics than Hg and Hs, suggesting Ht may be diagnosed differentially by cyst sizes and also host plant preferences. Hs showed smaller "a" value with more globular shape and stronger structures with more thickened and strengthened collagen-like texture of cyst wall than Hg and Ht. This suggests Hs may be diagnosed differently by structural characteristics from the others, especially Hg with similar cyst sizes. There were no significant differences in emergence (inoculum potential) among cyst nematodes due to the offset of fecundity and hatching rate; however, the inoculum potential of Hs may be not so persistent as Hg and Ht in fields because of its lower fecundity and higher hatching rate (causing rapid inoculum loss) than the others. These characteristics of cysts provide information useful for simple and differential diagnoses and reliable management of cyst nematodes.
Diagnostic methods for power transmission facilities are important for energy security because the growth of defects in power facilities increases the risk of blackouts in an entire power grid. ...However, damage in power transmission facilities is difficult to detect because cracks or defects are minuscule and are challenging to determine. One interesting phenomenon caused by damage in power transmission facilities is ultrasound emissions on a damaged surface. However, measuring ultrasound emissions to detect defects is limited by the severity of the surrounding noise. To overcome this limitation, this study proposes a new method for damage detection by fusing ultrasound measurements with recorded optical images. The proposed method consists of two phases. The first phase preprocesses ultrasound measurements for ultrasound feature extraction. This phase aims to detect the location of ultrasound emissions by analyzing ultrasound characteristics including the intensity and density. The second phase detects and classifies a damaged object with optical images recorded using a deep convolutional neural network. This phase not only discards the noise from the ultrasound measurements but also classifies a damaged system among many components in power transmission facilities. The experiments validate the effectiveness of the proposed method using ultrasound measurements and recorded images and finally suggest scenarios for potential applications.
Vibration isolation with mode decoupling plays a crucial role in the design of an intelligent robotic system. Specifically, a coupled multi-degree-of-freedom (multi-DOF) model accurately predicts ...responses of system dynamics; hence, it is useful for vibration isolation and control with mode decoupling. This study presents a vibration isolation method with mode decoupling based on system identification, including a coupled multi-DOF model to design intelligent robotic systems. Moreover, the entire procedure is described, including the derivation of the governing equation of the coupled multi-DOF model, estimation of the frequency response function, and parameter estimation using least squares approximation. Furthermore, the suggested methods were applied for a mobile surveillance system suffering from resonances with mode coupling; it made the monitoring performance of the surveillance camera deteriorate. The resonance problem was mitigated by installing vibration isolators, but limited to eliminate the coupling effects of natural frequency deterioration performances of vibration isolation. More seriously, system identification with a simple decoupled model limits the prediction of this phenomenon. Hence, it is difficult to enhance the performance of vibration isolators. In contrast, the presented method can accurately predict the vibration phenomenon and plays a critical role in vibration isolation. Therefore, dynamic characteristics were predicted based on a vibration isolator using the coupled three-DOF model, and a final suggestion is presented here. The experiments demonstrated that the suggested configuration decreased vibration up to 98.3%, 94.0%, and 94.5% in the operational frequency range, i.e., 30–85 Hz, compared to the original surveillance system in the fore-after, side-by-side, and vertical directions, respectively. The analysis suggests that the present method and procedure effectively optimize the vibration isolation performances of a drone containing a surveillance system.
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