• Korean Journal of Remote Sensing
• /
• v.39 no.5_4
• /
• pp.1155-1164
• /
• 2023

Currently, the National Forest Inventory (NFI) collects tree information by human, so the range and time of the survey are limited. Research is actively being conducted to extract tree information from a large area using aerial Light Detection And Ranging (LiDAR) and aerial photographs, but it does not reflect the characteristics of forest areas in Korea because it is conducted in areas with wide tree spacing or evenly spaced trees. Therefore, this study proposed a methodology for generating Digital Surface Model (DSM), Digital Elevation Model (DEM), and Canopy Height Model (CHM) images using aerial LiDAR, extracting the tree height through the local Maxima, and calculating the Diameter at Breath Height (DBH) through the DBH-tree height formula. The detection accuracy of trees extracted through the proposed methodology was 88.46%, 86.14%, and 84.31%, respectively, and the Root Mean Squared Error (RMSE) of DBH calculated based on the tree height formula was around 5cm, confirming the possibility of using the proposed methodology. It is believed that if standardized research on various types of forests is conducted in the future, the scope of automation application of the manual national forest resource survey can be expanded.

• Journal of Cadastre & Land InformatiX
• /
• v.53 no.2
• /
• pp.5-18
• /
• 2023

As the development of drones and sensors accelerates, new services and values are created by fusing data acquired from various sensors mounted on drone. However, the construction of spatial information through data fusion is mainly constructed depending on the image, and the quality of data is determined according to the specification and performance of the hardware. In addition, it is difficult to utilize it in the actual field because expensive equipment is required to construct spatial information of high-quality. In this study, super-resolution was performed by applying deep learning to low-resolution images acquired through RGB and THM cameras mounted on a drone, and quantitative evaluation and feature point extraction were performed on the generated high-resolution images. As a result of the experiment, the high-resolution image generated by super-resolution was maintained the characteristics of the original image, and as the resolution was improved, more features could be extracted compared to the original image. Therefore, when generating a high-resolution image by applying a low-resolution image to an super-resolution deep learning model, it is judged to be a new method to construct spatial information of high-quality without being restricted by hardware.

• Journal of Internet Computing and Services
• /
• v.25 no.2
• /
• pp.57-67
• /
• 2024

This paper explores the potential of electromyography (EMG) as a means of gesture recognition for user input in gesture-based interaction. EMG utilizes small electrodes within muscles to detect and interpret user movements, presenting a viable input method. To classify user gestures based on EMG data, machine learning techniques are employed, necessitating the preprocessing of raw EMG data to extract relevant features. EMG characteristics can be expressed through formulas such as Integrated EMG (IEMG), Mean Absolute Value (MAV), Simple Square Integral (SSI), Variance (VAR), and Root Mean Square (RMS). Additionally, determining the suitable time for gesture classification is crucial, considering the perceptual, cognitive, and response times required for user input. To address this, segment sizes ranging from a minimum of 100ms to a maximum of 1,000ms are varied, and feature extraction is performed to identify the optimal segment size for gesture classification. Notably, data learning employs overlapped segmentation to reduce the interval between data points, thereby increasing the quantity of training data. Using this approach, the paper employs four machine learning models (KNN, SVC, RF, XGBoost) to train and evaluate the system, achieving accuracy rates exceeding 96% for all models in real-time gesture input scenarios with a maximum segment size of 200ms.

• Food Science and Preservation
• /
• v.30 no.6
• /
• pp.983-990
• /
• 2023

This study was conducted to develop a preservation technology that can induce changes in physicochemical properties to effectively utilize of persimmon leaves. The application effects of steaming or freezing technique were investigated. Astringent persimmon leaves were steam-blanched (100℃, 30 sec) or frozen (-20℃, 15 d), followed by hot-air drying (50℃). The physicochemical properties of the extract obtained by hot-water leaching from the dried leaves were compared. The extract of leaves dried without pretreatment was used as a control. L* value was higher in steamed than in control and frozen. a* value was highest in the control. The browning index was higher in the frozen and lower in the steamed than in the control. Soluble solids were the highest in the steamed and the lowest in the frozen. Sucrose content was relatively high in the steamed, and the glucose and fructose contents were relatively high in the frozen. Total polyphenol content and DPPH radical scavenging activity were higher in steamed and lower in frozen than in control. Thus, it was confirmed that steam or freeze pretreatment after harvesting persimmon leaves affects the extraction yield, color, antioxidant capacity and component changes of dried persimmon leaves. Unlike steaming, freezing pretreatment showed the effect of promoting decomposition and browning reactions, and it is considered useful when such an effect is needed.

• Food Science and Preservation
• /
• v.31 no.3
• /
• pp.444-451
• /
• 2024

This study aimed to investigate the characteristics of protein hydrolysates derived from defatted egg yolk using various proteolytic enzymes and compare the antioxidant activity of the resulting hydrolysates. The defatted egg yolk powder was subjected to enzymatic hydrolysis using four different proteases (alcalase, bromelain, flavourzyme and neutrase), and the resulting hydrolysates were evaluated for their antioxidant properties. Through analysis of available amino group contents and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, it was observed that the defatted egg yolk powder treated with alcalase, flavourzyme, and neutrase for 12 h exhibited a high degree of hydrolysis value. Based on the RC₅₀ values obtained from two different antioxidant analyses, all hydrolysates showed comparable antioxidant activity, except for the alcalase hydrolysate, which demonstrated notably higher scavenging activity against hydrogen peroxide than the other hydrolysates. These findings suggest the potential of protein hydrolysates from defatted egg yolk, a by-product of lecithin extraction, as natural antioxidants.

• The Journal of Advanced Prosthodontics
• /
• v.16 no.4
• /
• pp.212-220
• /
• 2024

PURPOSE. This cone-beam computed tomography (CBCT) study aimed to analyze the anatomical characteristics of alveolar bone at mandibular first molar (MFM) and their implications for immediate implant placement surgery. MATERIALS AND METHODS. 100 patients with 140 MFMs were reviewed retrospectively. We first performed a 3D reconstruction of the patient's CBCT data to determine a reference plane with ideal implant placement and orientation. The following parameters of MFM region were analyzed: mesial-distal socket size (MDSS), buccal-lingual socket size (BL-SS), root furcation fornix to inferior alveolar nerve (IAN) distance (RF-I), interradicular bone thickness (IRB), mesial/distal root apex to the IAN distance (MRA-I/DRA-I), thickness of the buccal/lingual bone of the mesial root (MR-B/MR-L), thickness of the buccal/lingual bone of the distal root (DR-B/DR-L). RESULTS. The MD-SS of MFM was 8.74 ± 0.76 mm, and the BLSS was 8.26 ± 0.72 mm. The MR-B, DR-B was 1.01 ± 0.40 mm and 1.14 ± 0.50 mm, and the difference was statistically significant (P = .001). The values of the MR-L, DR-L were 2.71 ± 0.78 mm and 3.09 ± 0.73 mm, and the difference was also statistically significant (P < .001). The mean distance of RF-I was 15.68 ± 2.13 mm, and the MRA-I was 7.06 ± 2.22 mm, which was greater than that of DRA-I (6.48 ± 2.30 mm, P < .001). The IRB at 2 mm, 4 mm apical from the furcation fornix, and at apex level was 2.81 ± 0.50 mm, 3.30 ± 0.62 mm, and 4.44 ± 1.02 mm, respectively. CONCLUSION. There is relatively sufficient bone mass in interradicular bone in height, but an adequate width is lacking for the bone between the mesial and distal root after the extraction of the MFM for immediate implantation. The thickness of the MFM buccal bone is relative thin, especially for the mesial root.

• The Journal of the Convergence on Culture Technology
• /
• v.10 no.5
• /
• pp.681-686
• /
• 2024

Korea Post service provides public services to the public, including mail, deposits, and insurance. The work of the postal activities is labor-intensive and physically intensive. Postal workers are exposed to the risk of injury and musculoskeletal disorders, and delivery workers are exposed to the risk of traffic accidents. The Postal Service Headquarters has strengthened safety and health activities to improve hazardous risk factors in the field. In addition, we are promoting activities to spread safety culture continuously. However, it is difficult to determine whether these activities were applied well to the site of the affiliated institution, and it is not known whether they were effective in preventing safety accidents. In addition, there is no objective evaluation system, so the current level of safety and health and problems related to workplace safety and health cannot be identified. Therefore, in this study, we tried to prepare basic data to propose an evaluation system, standard, and evaluation index suitable for the postal business so that the safety level of the public postal business can be evaluated efficiently and objectively. In other words, it was intended to analyze the characteristics of the public postal business and prepare the basis for the development of evaluation indicators considering it, and through this, an effective level evaluation can be performed and problems in safety and health management by institution can be identified.

• Korean Journal of Optics and Photonics
• /
• v.13 no.4
• /
• pp.340-346
• /
• 2002

To understand the characteristics of the passively Q-switched Nd:YAG laser output energy with $Cr^{4+}$:YAG saturable absorbers, the transmissions of $Cr^{4+}$:YAG and the inversion population densities of Nd:YAG at the onset of Q-switch were experimentally analysed. The measured transmissions at the onset of Q-switch were 0.70$\pm$0.02 and 0.62$\pm$0.02 for the 0.48 and 0.38 of initial transmission, respectively. It means that the initial transmission loss of $Cr^{4+}$:YAG absorber is reduced in a low Q-state due to the initial absorbing effect of $Cr^{4+}$:YAG. In pumping stage, $Cr^{4+}$:YAG has absorbing processes due to the fluorescence and amplified spontaneous emissions of the Nd:YAG even if there is no laser oscillation. The minimum population inversion densities for Qswitch were approximately 3.7${\times}{10^{17}}$ and 4.0${\times}{10^{17}}$ $cm^{-3}$, respectively. At the beginning of Q-switch, the number density of $Cr^{4+}$ions in the ground state of $Cr^{4+}$:YAG was approximately 1.4${\times}{10^{17}}$ $cm^{-3}$ and the ratio of the ground to the excited state of absorbing $Cr^{4+}$ions was 0.44 both. The modified theoretical output energies with the initial absorbing effect were 18 and 18.5 mJ. The measured output energies were 17$\pm$1 and 18$\pm$1.5 mJ, respectively. The quantum extraction efficiencies of Q-switch were 0.32 both. The theoretical Q-switched output results with the initial absorbing effect of the saturable absorber are a good agreement with the experimental results.

• Korean Journal of Food Science and Technology
• /
• v.36 no.1
• /
• pp.44-49
• /
• 2004

Changes in quality properties of Kochujang prepared with Paecilomyces japonica powder and extract using different solvents were investigated during 90 days of fermentation at $20^{\circ}C$. Although moisture contents were not significantly different, pH of P. japonica-added Kochujang was lower than that of control group without P. japonica, and decreased with increasing fermentation time. Amino nitrogen content increased up to 60 days of fermentation and decreased slightly after 90 days, with that of P. japonica-added Kochujang showing highest on 30 and 60 days at 179.2 and 282.2 mg%, respectively, higher than control gruup. L, a, and b values decreased in proportion to fermentation period, with P. japonica-added Kochujang, particularly P. japonica powder-added Kochujang, lower than those of control g개up. Sensory evaluation test showed color of control group was 'clear red', whereas that of P. japonica powder-added Kochujang was 'dark reddish brown' and P. japonica extract-added Kochujang was darker than control group; consumer preference for dark color was low, Textures of all samples were 'glossy and smooth', showing high consumer preference. Salt content of P. japonica-added Kochujang was higher than that of control group, with P. japonica extract-added Kochujang higher than that made with powder Hot taste or P. japonica-added Kochujang was weaker, whereas its flavor higher, than control group, with P. japonica powder-added Kochujang showing highest flavor score. Overall preference was higher for P. japonica-added Kochujang than control group, with P. japonica water extract-added Kochujang showing the highest score.

• Culinary science and hospitality research
• /
• v.18 no.3
• /
• pp.163-179
• /
• 2012

This study was prepared to develop American sauce with different amounts of salt through high pressure extraction and examined difference in its mechanical and sensory characteristics. Furthermore, it aimed to provide practical materials for the mass production of American sauce and other crustacean sauce products and to contribute to the development of products with superior quality and functionality by standardizing traditional cooking techniques in the food service industry. In American sauce, salt content did not have a significant effect on water content and ash content but had a significant effect on color, pH and salinity. Na and K contents increased with increasing salt content. In addition, Mg and P contents were highest in J4 containing 0.4% of salt, but they did not show any regular tendency according to salt content. For total free amino acids, 29 kinds were detected in J0 and J1, 30 in J2, 31 in J3, and 33 in J4. Detection was highest in J3 containing 0.3% of salt, and the content level was highest particularly for arginine among essential amino acids, for glutamic acid, alanine, serine, ${\beta}$-alanine and ${\alpha}$-aminoadipic acid among flavor enhancing amino acids, and for ${\gamma}$-Aminoisobutyric acid among other amino acids. We measured lipid peroxidation in American sauce using lipid extracted from a mouse brain and confirmed that the amount of antioxidant substances extracted was largest in J0 containing no salt. The results of measuring lipid peroxidation and DPPH showed that the antioxidant effect was high when salt was not contained. In the results of the sensory test, overall quality was highest in J3 containing 0.3% of salt, showing that the addition of salt affects the evaluation of overall quality. Summing up the presents of this study as presented above, we cannot expect an effect of antioxidant functionality; however, according to the results of the mechanical quality evaluation and the sensory test, American sauce containing 0.3% of salt is considered the optimal product in terms of quality. Using these results as practical materials for the mass production of crustacean sauce products, we expect to standardize traditional cooking techniques in the food service industry and to develop products with high quality and functionality.