94 results on '"Kyeong Hwan Lee"'
Search Results
2. Rhodamine 6G derivative for the selective copper detection and remediation using nanoporous diatomaceous earth-engineered functional receptor
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Padmaja V. Mane, Pravin Patil, Anusha A. Mahishi, Madhuprasad Kigga, Mahesh P. Bhat, Kyeong-Hwan Lee, and Mahaveer Kurkuri
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Nanoporous ,Diatomaceous earth ,Colorimetric sensing ,Organic receptors ,Copper removal ,Device ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
A rhodamine-derived receptor was synthesized and comprehensively characterized for structural confirmation. The receptor was able to distinguish the copper ions (Cu2+) from other competing cations. The yellow color of the receptor changed to pink upon adding Cu2+ ions, however, other competing cations ions were impotent towards any color variation. The UV–visible titration studies revealed the binding stoichiometry of a 1:1 ratio with a detection limit of 9.663 × 10−8 M. Additionally, a novel idea of the work resides in the use of diatom for the practical application, where the receptor has been tethered on nanoporous diatomaceous earth microparticles (P2D) to remove Cu2+ ions. The results confirmed that 50 mg receptor functionalized DE could adsorb 10 mL of 1 ppm Cu2+ ions from water. Furthermore, a proof-of-concept device that is inexpensive, simple to operate, and continuously removes Cu2+ ions from water has been developed. The efficiency of the device in Cu2+ ion removal could be realized through the naked eye by observing the color change of P2D particles, which has excellent potential for application in remote locations where water contamination is a significant issue.
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- 2023
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3. Three-dimensional quantification of apple phenotypic traits based on deep learning instance segmentation.
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Xuhua Dong, Woo-Young Kim, Yu Zheng, Ju-Youl Oh, Reza Ehsani, and Kyeong-Hwan Lee
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- 2023
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4. Recent developments in microfluidic technology for synthesis and toxicity-efficiency studies of biomedical nanomaterials
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Akhilesh Bendre, Mahesh P. Bhat, Kyeong-Hwan Lee, Tariq Altalhi, Mohammed Ayad Alruqi, and Mahaveer Kurkuri
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Biomedical ,Nanoparticles ,Microfluidic device ,Organ-on-chip ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Microfluidic technology is a relatively new field among the various conventional bulk techniques employed for nanomaterial synthesis. Nanoparticles (NPs) produced using such methods generally have poor surface features, morphology, uncontrolled size and broad size distributions. NPs especially used in the biomedical sector require a degree of control over their size, morphology, and polydispersity to improve their functionality. To synthesize such NPs, microfluidic devices are ideal as parameters such as mixing rates, flow rates, mixing volumes, multiphase reactions can be controlled on the micro/nanoscale. There are several strategies and challenges in the synthesis of nanoparticles from organic and inorganic materials in a microfluidic platform. The challenges faced during the design and implementation of these devices, such as the large scale production and interaction with soft lithography materials, which are overcome by the use of the bulk technique in conjugation with microfluidics, use of parallelisation of the processes with the search for new fabrication materials. On the other hand, organ-on-chip (OOC) are analytical microfluidic devices in which cell cutures are present and can mimic an organ along with its physio-chemical properties to study cell-nanoparticle interaction. There are several issues with the construction of such devices as cell cultures within the device can be affected by the fabrication materials. As such new biocompatible materials are being printed into more appropriate designs, utilized to contain said cultures and reduce the risk of error in the analysis of NP properties, such as efficiency and toxicity. This review aims to discuss the recent developments in the field of synthesis as well as toxicity and efficacy evaluations of biomedical nanoparticles using microfluidic technology.
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- 2022
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5. Development of real-time onion disease monitoring system using image acquisition
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Du-Han KIM, Kyeong-Hwan LEE, Chang-Hyun CHOI, Tae-Hyun CHOI, Yong-Joo KIM
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imaging acquisition system ,disease ,downy mildew ,onion ,Agriculture (General) ,S1-972 - Abstract
In this study, real-time disease monitoring was conducted on onion which is the most representative crop in Republic of Korea, using an image acquisition system newly developed for the mobile measurement of phenotype. The purpose of this study was to improve the accuracy of prediction of disease and state variables by processing images acquired from monitoring. The image acquisition system was consisted of two parts, a motorized driving system and a PTZ (pan, tilt and zoom) camera to take images of the plants. The acquired images were processed as follows. Noise was removed through an image filter and RGB (red, green and blue) colors were converted to HSV (hue, saturation and value), which enabled thresholding of areas with different colors and properties for image binarization by comparing the color of onion leaf with ambient areas. Four objects with the most significant browning in the onion leaf to the naked eye were selected as the samples for data acquired. The thresholding method with image processing was found to be superior to the naked eye in identifying accurate disease areas. In addition, it was found that the incidence of disease was different in each disease area ratio. As a result, the use of image acquisition system in image processing analysis will enable more prompt detection of any changes in the onion and monitoring of disease outbreaks during the crop lifecycle.
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- 2018
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6. Automatic Rice Yield Estimation Using Image Processing Technique.
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Md Nasim Reza, In Seop Na, Sun Wook Baek, and Kyeong-Hwan Lee
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- 2017
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7. Detection of Abnormal Region for Pest Prediction in Paddy Field.
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Tean Chen, In Seop Na, Sun Wook Baek, and Kyeong-Hwan Lee
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- 2017
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8. Recent Advances in Microfluidic Platform for Physical and Immunological Detection and Capture of Circulating Tumor Cells
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Mahesh Padmalaya Bhat, Venkatachalam Thendral, Uluvangada Thammaiah Uthappa, Kyeong-Hwan Lee, Madhuprasad Kigga, Tariq Altalhi, Mahaveer D. Kurkuri, and Krishna Kant
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circulating tumor cells (CTCs) ,microfluidic device ,physical method ,biological method ,cancer diagnostics ,Biotechnology ,TP248.13-248.65 - Abstract
CTCs (circulating tumor cells) are well-known for their use in clinical trials for tumor diagnosis. Capturing and isolating these CTCs from whole blood samples has enormous benefits in cancer diagnosis and treatment. In general, various approaches are being used to separate malignant cells, including immunomagnets, macroscale filters, centrifuges, dielectrophoresis, and immunological approaches. These procedures, on the other hand, are time-consuming and necessitate multiple high-level operational protocols. In addition, considering their low efficiency and throughput, the processes of capturing and isolating CTCs face tremendous challenges. Meanwhile, recent advances in microfluidic devices promise unprecedented advantages for capturing and isolating CTCs with greater efficiency, sensitivity, selectivity and accuracy. In this regard, this review article focuses primarily on the various fabrication methodologies involved in microfluidic devices and techniques specifically used to capture and isolate CTCs using various physical and biological methods as well as their conceptual ideas, advantages and disadvantages.
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- 2022
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9. Canopy Volume Extraction of Citrus reticulate Blanco cv. Shatangju Trees Using UAV Image-Based Point Cloud Deep Learning
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Yuan Qi, Xuhua Dong, Pengchao Chen, Kyeong-Hwan Lee, Yubin Lan, Xiaoyang Lu, Ruichang Jia, Jizhong Deng, and Yali Zhang
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canopy volume ,UAV tilt photogrammetry ,point cloud ,deep learning ,Citrus reticulate Blanco cv. Shatangju trees ,Science - Abstract
Automatic acquisition of the canopy volume parameters of the Citrus reticulate Blanco cv. Shatangju tree is of great significance to precision management of the orchard. This research combined the point cloud deep learning algorithm with the volume calculation algorithm to segment the canopy of the Citrus reticulate Blanco cv. Shatangju trees. The 3D (Three-Dimensional) point cloud model of a Citrus reticulate Blanco cv. Shatangju orchard was generated using UAV tilt photogrammetry images. The segmentation effects of three deep learning models, PointNet++, MinkowskiNet and FPConv, on Shatangju trees and the ground were compared. The following three volume algorithms: convex hull by slices, voxel-based method and 3D convex hull were applied to calculate the volume of Shatangju trees. Model accuracy was evaluated using the coefficient of determination (R2) and Root Mean Square Error (RMSE). The results show that the overall accuracy of the MinkowskiNet model (94.57%) is higher than the other two models, which indicates the best segmentation effect. The 3D convex hull algorithm received the highest R2 (0.8215) and the lowest RMSE (0.3186 m3) for the canopy volume calculation, which best reflects the real volume of Citrus reticulate Blanco cv. Shatangju trees. The proposed method is capable of rapid and automatic acquisition for the canopy volume of Citrus reticulate Blanco cv. Shatangju trees.
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- 2021
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10. Improved 3D-Printability of Cellulose Acetate to Mimic Water Absorption in Plant Roots through Nanoporous Networks
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Gaoshuang Liu, Mahesh P. Bhat, Cheol Soo Kim, Jangho Kim, and Kyeong-Hwan Lee
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Inorganic Chemistry ,Polymers and Plastics ,Organic Chemistry ,Materials Chemistry - Published
- 2022
11. Drone-Based Three-Dimensional Photogrammetry and Concave Hull by Slices Algorithm for Apple Tree Volume Mapping
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Xuhua Dong, Woo-Young Kim, and Kyeong-Hwan Lee
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Photogrammetry ,Mechanical Engineering ,Hull ,Computer graphics (images) ,Apple tree ,Engineering (miscellaneous) ,Agricultural and Biological Sciences (miscellaneous) ,Drone ,Computer Science Applications ,Mathematics ,Volume (compression) - Published
- 2021
12. Power Transmission Efficiency Analysis of 42 kW Power Agricultural Tractor According to Tillage Depth during Moldboard Plowing
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Yeon-Soo Kim, Wan-Soo Kim, Md. Abu Ayub Siddique, Seung-Yun Baek, Seung-Min Baek, Su-Hwan Cheon, Sang-Dae Lee, Kyeong-Hwan Lee, Dong-Hyuck Hong, Seong-Un Park, and Yong-Joo Kim
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agricultural tractor ,tillage depth ,power transmission efficiency ,power requirements ,fuel efficiency ,moldboard plowing ,Agriculture - Abstract
In order to optimize tractor design and optimize efficiency during tillage operation, it is essential to verify the impact through field tests on factors affecting the tractor load. The objectives of this study were to investigate the effect of tillage depth on power transmission efficiency of 42 kW power agricultural tractor during moldboard plowing. A load measurement system and a tillage depth measurement system were configured for field tests. To analyze the effect of tillage depth on power transmission efficiency and fuel consumption, the data measured in the three-repeated field test were classified according to tillage depth. As the tillage depth increased from 11 cm at the top of the hardpan to 23 cm at the deepest, the required power of the engine increased by approximately 13% from 35.48 kW to 40.11 kW, and the power transmission efficiency also increased significantly from 66% to 95%. Among them, the power transmission efficiency of the rear axle was significantly increased from 38% to 59%, which was the most affected. As the tillage depth increased, the overall power requirement is greatly increased due to the resulting workload, but the fuel consumption and the specific fuel consumption are reduced because the engine speed of the tractor is reduced. As the tillage depth increased from 11 cm to 23 cm, the fuel consumption rate was rather reduced by 13.5% as the engine rotational speed decreased 11.3% due to the increase work load of tractor. In addition, the specific fuel consumption decreased from 302.44 g/kWh to 236.93 g/kWh, showing a fuel consumption saving of up to 21.7% during moldboard plow. In addition, as the tillage depth increased, the ratio of the value excluding the mechanical and hydraulic power requirements has significantly decreased from 34% to 5% as the power transmission efficiency increases. This study considers the soil properties according to the soil depth, as well as the power transmission efficiency and fuel consumption rate. The research results can provide useful information for research on power transmission efficiency and selection of an appropriate power source of agricultural tractor according to tillage depth during moldboard plowing and are expected to be used in various ways as basic studies of digital farming research in agricultural machinery.
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- 2020
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13. Arabidopsis Basic Helix-Loop-Helix 34 (bHLH34) Is Involved in Glucose Signaling through Binding to a GAGA Cis-Element
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Ji-Hee Min, Hyun-Woo Ju, Dayoung Yoon, Kyeong-Hwan Lee, Sungbeom Lee, and Cheol S. Kim
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activator ,AtPGR ,bHLH34 ,glucose-responsive element ,transcription factor ,Plant culture ,SB1-1110 - Abstract
The modulation of glucose (Glc) homeostasis and signaling is crucial for plant growth and development. Nevertheless, the molecular signaling mechanism by which a plant senses a cellular Glc level and coordinates the expression of Glc-responsive genes is still incompletely understood. Previous studies have shown that Arabidopsis thaliana plasma membrane Glc-responsive regulator (AtPGR) is a component of the Glc-responsive pathway. Here, we demonstrated that a transcription factor bHLH34 binds to 5′-GAGA-3′ element of the promoter region of AtPGR in vitro, and activates beta-glucuronidase (GUS) activity upon Glc treatment in AtPGR promoter-GUS transgenic plants. Gain- and loss-of-function analyses suggested that the bHLH34 involved in the responses to not only Glc, but also abscisic acid (ABA) and salinity. These results suggest that bHLH34 functions as a transcription factor in the Glc-mediated stress responsive pathway as well as an activator of AtPGR transcription. Furthermore, genetic experiments revealed that in Glc response, the functions of bHLH34 are different from that of a bHLH104, a homolog of bHLH34. Collectively, our findings indicate that bHLH34 is a positive regulator of Glc, and may affect ABA or salinity response, whereas bHLH104 is a negative regulator and epistatic to bHLH34 in the Glc response.
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- 2017
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14. Metal-Organic Frameworks (MOFs)-Based Carriers for Tumor Therapy
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Mahesh P. Bhat and Kyeong-Hwan Lee
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- 2022
15. Evaluation of the fatigue life of a tractor’s transmission spiral bevel gear
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Yong-Joo Kim, Kyeong-Hwan Lee, Yeon-Soo Kim, Changhyun Choi, Seong-Un Park, Dong-Hyuck Hong, and Wan-Soo Kim
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Tractor ,business.product_category ,business.industry ,Spiral bevel gear ,Mechanical Engineering ,010401 analytical chemistry ,Fatigue damage ,04 agricultural and veterinary sciences ,Structural engineering ,01 natural sciences ,0104 chemical sciences ,law.invention ,Transmission (mechanics) ,law ,040103 agronomy & agriculture ,Bevel gear ,0401 agriculture, forestry, and fisheries ,Life test ,business ,Agricultural tractor ,Spiral ,Mathematics - Abstract
Conventional tractor transmission spiral bevel gears are designed and evaluated based on the engine rated load, which is significantly higher than the load conditions in the field. In this study, the fatigue life of a spiral bevel gear is evaluated to obtain data for design optimization. The equivalent load was calculated using the field load data, and the integrated equivalent load was calculated based on the annual usage of major field operations in Korea. The fatigue life of three spiral bevel gear samples was evaluated using the accelerated life test (ALT) under an engine rated load condition of 120%. It was also evaluated under engine rated, plow equivalent, and integrated equivalent load. Fatigue life was estimated using the ALT results and the fatigue damage exponent based on the ALT equation. We observed that the fatigue life of the spiral bevel gear under the plow equivalent and integrated equivalent loads is higher than that under the rated load by 214 and 9,400 times, respectively. The results of this study can provide useful information for the design optimization of tractor transmission spiral bevel gears considering the field equivalent load.
- Published
- 2021
16. Strength Analysis of a PTO (Power Take-Off) Gear-Train of a Multi-Purpose Cultivator during a Rotary Ditching Operation
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Yeon-Soo Kim, Pa-Ul Lee, Wan-Soo Kim, Oh-Won Kwon, Chang-Won Kim, Kyeong-Hwan Lee, and Yong-Joo Kim
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cultivator ,power take off (PTO) gear-train ,rotary ditching ,gear strength ,Technology - Abstract
Optimal design of transmission gears is important to ensure product durability and reliability. This study measured a multi-purpose cultivator during a rotary ditching operation and analyzed the strength of the power take off (PTO) gear-train for the cultivator using analysis software (KISSsoft, KISSsoft AG—A Gleason Company, Bubikon, Switzerland) based on ISO 6336 standards and a modified Miner’s rule. A load measurement system was installed on the cultivator to measure the load on the PTO shaft. To measure the load on the PTO shaft, the load measuring system consisting of a data acquisition board (NI USB-6212, National Instruments, Austin, TX, USA) and a torque sensor was installed on the cultivator. Rotary ditching operations were conducted at two ground speeds and two PTO rotational speeds on a field with the same soil conditions. The measured load data were constructed using the rainflow-counting algorithm and the Smith-Watson-Topper equation. When the ground speed or PTO rotational speed increased, the average and maximum PTO torque increased significantly. The average measured torque ratio to rated torque of the PTO input shaft (19.6 Nm) was in the range of 50.1–105.9%. The simulation results using the actual measurement load indicated that the strength of the PTO gear-train tended to decrease with higher transmission gear stage and lower PTO gear stage except for the G2 and G3 gears. The simulation results of the safety factor for contact stress were lower than the minimum safety factor of ‘1.0’ at the T2P1 gear stage (G4 and G2). The simulation results of the fatigue life analysis showed fatigue life of less than service life (1000 h) at T2P2 (G2) and T2P1 (G2, G3, and G4). The simulation results indicate that there is a possibility of gear failure before service life at the T2P1 (G2, G3, and G4) and T2P2 (G2). It is known that the weak parts (G2, G3, and G4) should be the focus of design optimization through gear strength simulation to meet upward of a 1.0 safety factor and service life.
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- 2019
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17. Low-Bitrate Video Coding using Adaptive Wavelet Quantization of Difference Image.
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Kyeong-Hwan Lee and Won-Kyo Jeong
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- 2004
18. Paper-based colorimetric sensor for easy and simple detection of polygalacturonase activity aiming for diagnosis of Allium white rot disease
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Mi Rha Lee, Young-Soo Choi, Kwang-Yeol Yang, Cheol Soo Kim, and Kyeong-Hwan Lee
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Paper ,02 engineering and technology ,Polygalacturonase activity ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,Colorimetric sensor ,Ascomycota ,Limit of Detection ,Spectrophotometry ,medicine ,Environmental Chemistry ,Pectinase ,Spectroscopy ,Plant Diseases ,Detection limit ,Chromatography ,medicine.diagnostic_test ,biology ,Chemistry ,010401 analytical chemistry ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Plant disease ,0104 chemical sciences ,Polygalacturonase ,Allium ,Colorimetry ,0210 nano-technology ,Quantitative analysis (chemistry) - Abstract
Polygalacturonase (PG) activity in plants can serve as an important index for plant disease. However, the conventional method to detect PG activity is a complex process and requires a skilled technician and expensive analytical equipment. In this study, a paper-based colorimetric sensor was developed based on the principle of the ruthenium red (RR) dye method for easy and simple measurement of PG activity. The proposed paper-based sensor has a three-layer structure for detection of PG activity in samples. The sensor sensitivity was enhanced by optimizing the pH of the sodium acetate buffer used in polygalacturonic acid (PGA)-RR complex formation and the reaction temperature for PG and the PGA-RR complex. Further, for quantitative analysis of PG activity, Delta RGB analysis was conducted to detect color changes in the sensing window of the sensor. Results presented that the linear measurement range of the paper sensor was 0.02-0.1 unit with the limit of detection of 0.02 unit, which showed a similar detection range, but a lower detection limit, compared to the spectrophotometry. Furthermore, PG activity based on culture condition was measured using samples from Sclerotium cepivorum to verify the potential application of the developed paper-based sensor in the field. The measured activity showed no statistically significant difference from the values obtained from the spectrophotometry at 95% confidence level. Therefore, the paper-based colorimetric sensor can be used to predict plant diseases in Allium crops during the stage of pathogen invasion, potentially contributing to the improvement of crop production.
- Published
- 2020
19. Highly sensitive enclosed multilayer paper-based microfluidic sensor for quantifying proline in plants
- Author
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Cheol Soo Kim, Min Kyu Im, Mi Rha Lee, Young-Soo Choi, and Kyeong-Hwan Lee
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Paper ,Proline ,Surface Properties ,Microfluidics ,Arabidopsis ,Evaporation ,02 engineering and technology ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,chemistry.chemical_compound ,Environmental Chemistry ,Particle Size ,Spectroscopy ,Detection limit ,Wax ,Molecular Structure ,Chemistry ,fungi ,010401 analytical chemistry ,Ninhydrin ,food and beverages ,Microfluidic Analytical Techniques ,Contamination ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,visual_art ,visual_art.visual_art_medium ,Indicators and Reagents ,0210 nano-technology ,Biological system ,Quantitative analysis (chemistry) - Abstract
Free proline, termed proline, is a biomarker used for diagnosing drought stress in plants. A previously developed proline–ninhydrin reaction-based paper sensor could quickly and easily detect proline, but it was limited by low sensitivity. In this study, we developed an enclosed multilayer paper-based microfluidic sensor with high sensitivity for the quantitative detection of proline in plants. The multilayer paper-based sensor was manufactured using simple wax printing and origami methods, and contained an internal mixing channel to allow good mixing of the proline with ninhydrin, increasing the proline–ninhydrin reactivity and providing accurate and sensitive proline detection. By preloading ninhydrin onto the sample loading area, uniform coloration of the sensing window was achieved, allowing quantitative analysis of various proline concentrations using a constant reaction time. Only the sensing window and sample loading area were exposed to limit sample evaporation and contamination from the external environment. The LOD of the fabricated sensor was 23 μM, which is approximately 29-fold lower than that of the previously proposed paper sensor (657 μM). Samples were extracted from A. thaliana plants subjected to drought stress for proline detection. The proline concentrations measured using the developed paper sensor and a spectrophotometric method were not statistically significant at a confidence level of 95%. Therefore, the developed sensor can be applied to measure proline concentrations precisely in the field with a low detection limit. The developed paper-based sensor can be used to detect the early stages of drought in plants and thus improve crop productivity.
- Published
- 2020
20. A basic helix-loop-helix 104 (bHLH104) protein functions as a transcriptional repressor for glucose and abscisic acid signaling in Arabidopsis
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Ji-Hee Min, Sungbeom Lee, Hyun-Woo Ju, Cheol Soo Kim, Kyeong-Hwan Lee, Yun-Ha Jang, and Cho-Rong Park
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0106 biological sciences ,0301 basic medicine ,Physiology ,Arabidopsis ,Regulator ,Electrophoretic Mobility Shift Assay ,macromolecular substances ,Plant Science ,Real-Time Polymerase Chain Reaction ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Genetics ,Abscisic acid ,Transcription factor ,Basic helix-loop-helix ,biology ,Arabidopsis Proteins ,Basic Helix-Loop-Helix Leucine Zipper Transcription Factors ,Chemistry ,fungi ,food and beverages ,Promoter ,Plants, Genetically Modified ,biology.organism_classification ,Recombinant Proteins ,Cell biology ,carbohydrates (lipids) ,Glucose ,030104 developmental biology ,lipids (amino acids, peptides, and proteins) ,Signal transduction ,Energy source ,Abscisic Acid ,Signal Transduction ,010606 plant biology & botany - Abstract
Transduction of glucose (Glc) signaling is critical for plant development, metabolism, and stress responses. However, identifying initial Glc sensing and response stimulating mechanisms in plants has been difficult due to dual functions of glucose as energy sources and signaling component. A basic Helix-Loop-Helix 104 (bHLH104) protein is a homolog of bHLH34 previously isolated from Arabidopsis that functions as a transcriptional activator of Glc and abscisic acid (ABA) responses. In this study, we characterized bHLH104 as a transcription factor that binds to the regulatory region of Arabidopsis Plasma membrane Glc-responsive Regulator (AtPGR) gene. The bHLH104 binds to 5'-AANA-3' element of the promoter region of AtPGR in vitro and represses beta-glucuronidase (GUS) activity in AtPGR promoter-GUS transgenic plants. Genetic approaches show that bHLH104 positively regulates Glc and abscisic acid (ABA) response. These results suggest that bHLH104 is involved in Glc- and ABA-mediated signaling pathway. Taken together, these findings provide evidence that bHLH104 is an important transcription regulator in plant-sensitivity to Glc and ABA signaling.
- Published
- 2019
21. Variable Fertilizer Recommendation for Grass Production by Image–based Growth Status
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Geung-Joo Lee, Kyeong Hwan Lee, Sun-Ok Chung, Bo–Eun Jang, Eiji Inoue, Md. Shaha Nur Kabir, Yong-Joo Kim, and Takashi Okayasu
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Variable (computer science) ,engineering ,Production (economics) ,Environmental science ,Fertilizer ,Agricultural engineering ,engineering.material ,Agronomy and Crop Science ,Image based ,Biotechnology - Published
- 2019
22. Rice yield estimation based on K-means clustering with graph-cut segmentation using low-altitude UAV images
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Nasim Reza, Kyeong-Hwan Lee, In Seop Na, and Sun Wook Baek
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Ground truth ,Pixel ,business.industry ,010401 analytical chemistry ,k-means clustering ,Soil Science ,Image processing ,Pattern recognition ,04 agricultural and veterinary sciences ,01 natural sciences ,0104 chemical sciences ,Control and Systems Engineering ,Approximation error ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,RGB color model ,Segmentation ,Artificial intelligence ,Cluster analysis ,business ,Agronomy and Crop Science ,Food Science ,Mathematics - Abstract
Predicting the harvest yield enables farm practices to be modified throughout the growing season, with potential to increase the final yield. Unmanned aerial vehicle (UAV) based remote sensing is a promising way to estimate crop yields. In this study, rice yield was estimated by segmenting grain areas using low altitude RGB images collected using a rotary-wing type UAV. In particular, an image processing method that combines K-means clustering with a graph-cut (KCG) algorithm was proposed to segment the rice grain areas. The graph-cut algorithm was applied to extract the foreground and background of the images. The foreground RGB images were converted to the Lab colour space and then K-means clustering was used to label pixels based on colour information. The area of the rice grains in the images was calculated from the clustered images. Using this grain area information, the rice yield of the field could be estimated. Experiments show that the proposed method can segment the grain areas with a relative error of 6%–33%, and it improved the relative error of the previous method (by 1%–31%). The coefficient of determination between the results of the proposed method and the ground truth was found to be 0.98. Furthermore, the relative error of the yield estimation for four field sections was 21%–31%. The results indicate that the UAV image-based grain segmentation has the potential to estimate rice yield accurately and conveniently.
- Published
- 2019
23. Development of real-time onion disease monitoring system using image acquisition
- Author
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Changhyun Choi, Kyeong-Hwan Lee, Du-Han Kim, Tae-Hyun Choi, and Yong-Joo Kim
- Subjects
General Veterinary ,Computer science ,Real-time computing ,fungi ,Image acquisition ,food and beverages ,Disease monitoring ,lcsh:Agriculture (General) ,General Agricultural and Biological Sciences ,lcsh:S1-972 ,imaging acquisition system|disease|downy mildew|onion ,Biotechnology - Abstract
In this study, real-time disease monitoring was conducted on onion which is the most representative crop in Republic of Korea, using an image acquisition system newly developed for the mobile measurement of phenotype. The purpose of this study was to improve the accuracy of prediction of disease and state variables by processing images acquired from monitoring. The image acquisition system was consisted of two parts, a motorized driving system and a PTZ (pan, tilt and zoom) camera to take images of the plants. The acquired images were processed as follows. Noise was removed through an image filter and RGB (red, green and blue) colors were converted to HSV (hue, saturation and value), which enabled thresholding of areas with different colors and properties for image binarization by comparing the color of onion leaf with ambient areas. Four objects with the most significant browning in the onion leaf to the naked eye were selected as the samples for data acquired. The thresholding method with image processing was found to be superior to the naked eye in identifying accurate disease areas. In addition, it was found that the incidence of disease was different in each disease area ratio. As a result, the use of image acquisition system in image processing analysis will enable more prompt detection of any changes in the onion and monitoring of disease outbreaks during the crop lifecycle.
- Published
- 2018
24. BES1/BZR1 Homolog 3 cooperates with E3 ligase AtRZF1 to regulate osmotic stress and brassinosteroid responses in Arabidopsis
- Author
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Kyeong-Hwan Lee, Cho-Rong Park, Cheol Soo Kim, Tinh Van Nguyen, and Sungbeom Lee
- Subjects
Osmotic shock ,biology ,Physiology ,Chemistry ,Abiotic stress ,Arabidopsis Proteins ,Ubiquitin-Protein Ligases ,Mutant ,Arabidopsis ,Plant Science ,biology.organism_classification ,Plants, Genetically Modified ,Ubiquitin ligase ,Cell biology ,DNA-Binding Proteins ,chemistry.chemical_compound ,Gene Expression Regulation, Plant ,Osmotic Pressure ,Brassinosteroids ,biology.protein ,Arabidopsis thaliana ,Brassinosteroid ,Abscisic acid - Abstract
Proline (Pro) metabolism plays important roles in protein synthesis, redox balance, and abiotic stress response. However, it is not known if cross-talk occurs between proline and brassinosteroid (BR) signaling pathways. Here, an Arabidopsis intergenic enhancer double mutant, namely proline content alterative 41 (pca41), was generated by inserting a T-DNA tag in the Arabidopsis thaliana ring zinc finger 1 (atrzf1 ) mutant background. pca41 had a T-DNA inserted at the site of the gene encoding BES1/BZR1 Homolog 3 (BEH3). pca41 has a drought-insensitive phenotype that is stronger than atrzf1 under osmotic stress, including high Pro accumulation and decreased amounts of reactive oxygen species. Analysis of physiological, genetic, and molecular networks revealed that negative regulation of BEH3 during abiotic stress was linked to the BR signaling pathway. Our data also suggest that AtRZF1, an E3 ubiquitin ligase, might control osmotic stress, abscisic acid, and BR responses in a BEH3-dependent manner. Under darkness, pca41 displays a long hypocotyl phenotype, which is similar to atrzf1 and beh3, suggesting that BEH3 acts in the same pathway as AtRZF1. Overexpression of BEH3 results in an osmotic stress-sensitive phenotype, which is reversed by exogenous BR application. Taken together, our results indicate that AtRZF1 and BEH3 may play important roles in the osmotic stress response via ubiquitination and BR signaling.
- Published
- 2020
25. Reduced-Order Algorithm for Eigenvalue Assignment of Singularly Perturbed Linear Systems
- Author
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Heonjong Yoo, Kyeong Hwan Lee, and Zoran Gajic
- Subjects
Computer Science::Machine Learning ,Singular perturbation ,Article Subject ,General Mathematics ,MathematicsofComputing_NUMERICALANALYSIS ,010103 numerical & computational mathematics ,02 engineering and technology ,Computer Science::Digital Libraries ,01 natural sciences ,Reduced order ,Eigenvalue assignment ,Statistics::Machine Learning ,ComputingMethodologies_SYMBOLICANDALGEBRAICMANIPULATION ,0202 electrical engineering, electronic engineering, information engineering ,QA1-939 ,0101 mathematics ,Algebraic number ,Mathematics ,Linear system ,General Engineering ,Engineering (General). Civil engineering (General) ,Rate of convergence ,Computer Science::Mathematical Software ,020201 artificial intelligence & image processing ,TA1-2040 ,Sylvester equation ,Algorithm - Abstract
In this paper, we present an algorithm for eigenvalue assignment of linear singularly perturbed systems in terms of reduced-order slow and fast subproblem matrices. No similar algorithm exists in the literature. First, we present an algorithm for the recursive solution of the singularly perturbed algebraic Sylvester equation used for eigenvalue assignment. Due to the presence of a small singular perturbation parameter that indicates separation of the system variables into slow and fast, the corresponding algebraic Sylvester equation is numerically ill-conditioned. The proposed method for the recursive reduced-order solution of the algebraic Sylvester equations removes ill-conditioning and iteratively obtains the solution in terms of four reduced-order numerically well-conditioned algebraic Sylvester equations corresponding to slow and fast variables. The convergence rate of the proposed algorithm is Oε, where ε is a small positive singular perturbation parameter.
- Published
- 2020
- Full Text
- View/download PDF
26. Optimization of the ninhydrin reaction and development of a multiwell plate-based high-throughput proline detection assay
- Author
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Young-Soo Choi, Mi Rha Lee, Tusan Park, Kyeong-Hwan Lee, and Cheol Soo Kim
- Subjects
0106 biological sciences ,0301 basic medicine ,Proline ,Trace Amounts ,Arabidopsis ,Biophysics ,01 natural sciences ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Stress, Physiological ,Multiplex ,Molecular Biology ,Phosphoric acid ,Sulfosalicylic acid ,Chromatography ,Chemistry ,Extraction (chemistry) ,Ninhydrin ,Water ,Cell Biology ,Plant Leaves ,030104 developmental biology ,Reagent ,010606 plant biology & botany - Abstract
We developed a high-throughput technique for highly sensitive measurement of trace amounts of proline, an indicator of drought stress in plants, using an optimized proline-ninhydrin reaction. In order to do this, proline detection time was minimized by omitting phosphoric acid from the ninhydrin reagent. Chromophore extraction using toluene was also omitted, thus lowering the risks to environment and human health, and allowing the use of readily available polystyrene plates. Proline detection sensitivity was assessed based on the concentration of sulfosalicylic acid in the solution, which indicated that 1% sulfosalicylic acid yielded the best sensitivity and linearity. These findings were applied to a multiwell plate-based multiplex analysis using a dry oven for the simultaneous analysis of a large number of drought-stressed plant samples with trace amounts of proline. The results showed that proline could be effectively detected in plants grown in soil with water content under 5%, demonstrating its potential for diagnosing drought early. The proposed multiwell plate-based multiplex assay is expected to be useful in manifold agricultural applications.
- Published
- 2018
27. PCA22 acts as a suppressor of atrzf1 to mediate proline accumulation in response to abiotic stress in Arabidopsis
- Author
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Ji-Hee Min, Kyeong-Hwan Lee, Cheol Soo Kim, and Ah-Reum Kim
- Subjects
0106 biological sciences ,0301 basic medicine ,Proline ,AtRZF1 ,Physiology ,Mutant ,Arabidopsis ,Mutagenesis (molecular biology technique) ,Plant Science ,suppressor ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Gene Expression Regulation, Plant ,Stress, Physiological ,proline metabolism ,Botany ,otorhinolaryngologic diseases ,Arabidopsis thaliana ,Amino Acid Sequence ,Abscisic acid ,Phylogeny ,Suppressor mutation ,pca mutant ,biology ,Arabidopsis Proteins ,Abiotic stress ,Chemistry ,fungi ,Abiotic stress response ,Intracellular Signaling Peptides and Proteins ,food and beverages ,Plants, Genetically Modified ,biology.organism_classification ,Cell biology ,pollen tube length ,030104 developmental biology ,Sequence Alignment ,Research Paper ,010606 plant biology & botany - Abstract
Highlight PCA22 negatively regulates the drought response through the modulation of osmolytic components and regulates pollen tube length in Arabidopsis., Proline metabolism is important for environmental responses, plant growth, and development. However, its precise roles in plant abiotic stress tolerance are not well understood. Mutants are valuable for the identification of new genes and for elucidating their roles in physiological mechanisms. We applied a suppressor mutation approach to identify novel genes involved in the regulation of proline metabolism in Arabidopsis. Using the atrzf1 (Arabidopsis thaliana ring zinc finger 1) mutant as a parental line for activation tagging mutagenesis, we selected several mutants with suppressed induction of proline accumulation under dehydration conditions. One of the selected mutants [proline content alterative 22 (pca22)] appeared to have reduced proline contents compared with the atrzf1 mutant under drought stress. Generally, pca22 mutant plants displayed suppressed atrzf1 insensitivity to dehydration and abscisic acid during early seedling growth. Additionally, the pca22 mutant exhibited shorter pollen tube length than wild-type (WT) and atrzf1 plants. Furthermore, PCA22-overexpressing plants were more sensitive to dehydration stress than the WT and RNAi lines. Green fluorescent protein-tagged PCA22 was localized to the cytoplasm of transgenic Arabidopsis cells. Collectively, these results suggest that pca22 acts as dominant suppressor mutant of atrzf1 in the abiotic stress response.
- Published
- 2017
28. Eggshell membrane: Review and impact on engineering
- Author
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Daun Kim, Hoon Seonwoo, Kyeong-Hwan Lee, Kyoung Soon Choi, Dohyeon Lee, Ki-Taek Lim, Jangho Kim, and Sunho Park
- Subjects
Engineering ,business.industry ,Soil Science ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Commercialization ,0104 chemical sciences ,Biological engineering ,Electric devices ,Control and Systems Engineering ,Fabrication methods ,Biochemical engineering ,Eggshell membrane ,0210 nano-technology ,business ,Agronomy and Crop Science ,Food Science - Abstract
Agricultural bioresources are being recognised as emerging functional platforms that can find application in biological, environmental, and agricultural engineering. Eggshell membrane (ESM), the protein-rich membrane between the eggshell and egg white, has usually been regarded as waste and overlooked. However, its potential is now being highlighted in many engineering fields. This review provides basic information about ESM starting with its structural, chemical, and physical properties, and expands on its role in engineering fields. It touches upon various fabrication methods for constructing compatible ESM-based functional platforms. The review focuses on the role and performance of ESM in engineering applications: electric devices, sensors, environmental engineering, biomedical engineering, and commercialization. Finally, new perspectives about the potential of ESM as a highly valuable bioresource in various engineering fields are discussed.
- Published
- 2016
29. Strength Analysis of a PTO (Power Take-Off) Gear-Train of a Multi-Purpose Cultivator during a Rotary Ditching Operation
- Author
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Ohwon Kwon, Changwon Kim, Yeon-Soo Kim, Wan-Soo Kim, Kyeong-Hwan Lee, Pa-Ul Lee, and Yong-Joo Kim
- Subjects
0106 biological sciences ,rotary ditching ,Control and Optimization ,Energy Engineering and Power Technology ,01 natural sciences ,lcsh:Technology ,Automotive engineering ,law.invention ,Gear train ,cultivator ,law ,Torque ,Torque sensor ,Electrical and Electronic Engineering ,Power take-off ,Engineering (miscellaneous) ,Mathematics ,power take off (PTO) gear-train ,Renewable Energy, Sustainability and the Environment ,lcsh:T ,Rotational speed ,04 agricultural and veterinary sciences ,Building and Construction ,Transmission (mechanics) ,gear strength ,Ground speed ,Service life ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,010606 plant biology & botany ,Energy (miscellaneous) - Abstract
Optimal design of transmission gears is important to ensure product durability and reliability. This study measured a multi-purpose cultivator during a rotary ditching operation and analyzed the strength of the power take off (PTO) gear-train for the cultivator using analysis software (KISSsoft, KISSsoft AG&mdash, A Gleason Company, Bubikon, Switzerland) based on ISO 6336 standards and a modified Miner&rsquo, s rule. A load measurement system was installed on the cultivator to measure the load on the PTO shaft. To measure the load on the PTO shaft, the load measuring system consisting of a data acquisition board (NI USB-6212, National Instruments, Austin, TX, USA) and a torque sensor was installed on the cultivator. Rotary ditching operations were conducted at two ground speeds and two PTO rotational speeds on a field with the same soil conditions. The measured load data were constructed using the rainflow-counting algorithm and the Smith-Watson-Topper equation. When the ground speed or PTO rotational speed increased, the average and maximum PTO torque increased significantly. The average measured torque ratio to rated torque of the PTO input shaft (19.6 Nm) was in the range of 50.1&ndash, 105.9%. The simulation results using the actual measurement load indicated that the strength of the PTO gear-train tended to decrease with higher transmission gear stage and lower PTO gear stage except for the G2 and G3 gears. The simulation results of the safety factor for contact stress were lower than the minimum safety factor of &lsquo, 1.0&rsquo, at the T2P1 gear stage (G4 and G2). The simulation results of the fatigue life analysis showed fatigue life of less than service life (1000 h) at T2P2 (G2) and T2P1 (G2, G3, and G4). The simulation results indicate that there is a possibility of gear failure before service life at the T2P1 (G2, G3, and G4) and T2P2 (G2). It is known that the weak parts (G2, G3, and G4) should be the focus of design optimization through gear strength simulation to meet upward of a 1.0 safety factor and service life.
- Published
- 2019
- Full Text
- View/download PDF
30. Sensor Comparison for Grass Growth Estimation
- Author
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Md. Shaha Nur Kabir, Sun-Ok Chung, Yong-Joo Kim, Takashi Okayasu, Kyeong Hwan Lee, Geung-Joo Lee, Eiji Inoue, and Seung Hwa Yu
- Subjects
Environmental science ,Ultrasonic sensor ,Camera image ,Precision agriculture ,Agronomy and Crop Science ,Biotechnology ,Optical reflectance ,Remote sensing - Published
- 2016
31. Sensing Technology for Rapid Detection of Phosphorus in Water: A Review
- Author
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Kyeong-Hwan Lee, Jin-Tae Jeong, Sumaiya Islam, and Nasim Reza
- Subjects
Analyte ,Chemistry ,business.industry ,Mechanical Engineering ,Phosphorus ,010401 analytical chemistry ,Microfluidics ,Analytical chemistry ,chemistry.chemical_element ,02 engineering and technology ,Repeatability ,021001 nanoscience & nanotechnology ,01 natural sciences ,Agricultural and Biological Sciences (miscellaneous) ,0104 chemical sciences ,Computer Science Applications ,Chemical species ,Reagent ,Water quality ,0210 nano-technology ,Process engineering ,business ,Eutrophication ,Engineering (miscellaneous) - Abstract
Purpose: Phosphorus is an essential element for water quality control. Excessive amounts of phosphorus causes algal bloom in water, which leads to eutrophication and a decline in water quality. It is necessary to maintain the optimum amount of phosphorus present. During the last decades, various studies have been conducted to determine phosphorus content in water. In this study, we present a comprehensive overview of colorimetric, electrochemical, fluorescence, microfluidic, and remote sensing technologies for the measurement of phosphorus in water, along with their working principles and limitations. Results: The colorimetric techniques determine the concentration of phosphorus through the use of colorgenerating reagents. This is specific to a single chemical species and inexpensive to use. The electrochemical techniques operate by using a reaction of the analyte of interest to generate an electrical signal that is proportional to the sample analyte concentration. They show a good linear output, good repeatability, and a high detection capacity. The fluorescence technique is a kind of spectroscopic analysis method. The particles in the sample are excited by irradiation at a specific wavelength, emitting radiation of a different wavelength. It is possible to use this for quantitative and qualitative analysis of the target analyte. The microfluidic techniques incorporate several features to control chemical reactions in a micro device of low sample volume and reagent consumption. They are cheap and rapid methods for the detection of phosphorus in water. The remote sensing technique analyzes the sample for the target analyte using an optical technique, but without direct contact. It can cover a wider area than the other techniques mentioned in this review. Conclusion: It is concluded that the sensing technologies reviewed in this study are promising for rapid detection of phosphorus in water. The measurement range and sensitivity of the sensors have been greatly improved recently.
- Published
- 2016
32. Development of a Plow Tillage Cycle for an Agricultural Tractor
- Author
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Dae-Hyun Lee, Beom-Soo Shin, Yong-Joo Kim, Changhyun Choi, Kyeong-Hwan Lee, and Sun-Ok Chung
- Subjects
Tractor ,Engineering ,business.product_category ,Dynamometer ,business.industry ,Biomedical Engineering ,Soil Science ,Forestry ,02 engineering and technology ,Agricultural engineering ,021001 nanoscience & nanotechnology ,Tillage ,Plough ,Axle ,Agronomy ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,0210 nano-technology ,business ,Agronomy and Crop Science ,Hydraulic pump ,Agricultural tractor ,Driving cycle ,Food Science - Abstract
Various field tests are needed to improve agricultural tractor performance; however, field tests require expenditures for constructing an experiment system and time for conducting the tests repeatedly. In addition, it is difficult to acquire reliable data because field tests depend on environmental conditions. For this reason, indoor tests using dynamometers have been used in the automotive industry instead of field tests. To ensure the reliability of indoor tests, standardized driving cycles are needed as input data for the dynamometer. Therefore, this study aimed to develop a standardized plow tillage cycle for agricultural tractors using real field data. A load measurement system was installed on a tractor to collect real field data from loads acting on the four driving axles and the hydraulic pumps. Plow tillage was conducted on ten farmlands of similar size (3000 m 2 ; 100 m x 30 m) at three sites (A, B, and C). The plow tillage cycles for each site were developed using the driving cycle construction method for conventional vehicles with the measured load data. At one site, the entire dataset from the ten farmlands was first classified into micro-trips, which were the minimum patterns of plow tillage including plowing, three-point hitch ascending, and tractor turning. The arbitrary working cycles were generated by combining micro-trips, and less than 5% absolute percentage error was achieved between the entire dataset and the generated arbitrary working cycle. Second, the plow tillage cycle was determined considering the sum square difference (SSD) with a torque and torque variation probability distribution. The selected working cycle with the lowest SSD was determined as the plow tillage cycle. Third, the performance values (PVs) of the plow tillage cycles of agricultural tractors and the driving cycles of conventional vehicles were compared to evaluate the performance of the plow tillage cycle. The results showed that the ranges of absolute percentage error relative to the entire dataset were 1.0% to 4.9% for all sites. The SSDs of the plow tillage cycles were 1195.96, 958.77, and 1202.50, and the PVs of the plow tillage cycles were 99.60, 77.90, and 84.15 for sites A, B, and C, respectively. The PVs of the commonly used driving cycles were low, at 60% to 125% of the plow tillage cycles. The plow tillage cycles had especially higher performance than some of the international standard driving cycles by 104% to 125% for site B. The results showed that the developed plow tillage cycles can be applied to indoor tests for performance evaluation of agricultural tractors.
- Published
- 2016
33. A Dielectrophoresis Microfluidic Device for Trapping Bioparticles at Low Voltage and Frequency
- Author
-
Jin-Tae Jeong, Hyun-Min Shin, Duwoon Kim, and Kyeong-Hwan Lee
- Subjects
Materials science ,Polydimethylsiloxane ,business.industry ,Mechanical Engineering ,Microfluidics ,Nanotechnology ,Dielectrophoresis ,Bead ,Agricultural and Biological Sciences (miscellaneous) ,Signal ,Fluorescence ,Computer Science Applications ,chemistry.chemical_compound ,chemistry ,visual_art ,Electrode ,visual_art.visual_art_medium ,Optoelectronics ,business ,Engineering (miscellaneous) ,Low voltage - Abstract
Purpose: The necessity for precise manipulation of bioparticles has greatly increased in the fields of bioscience, biomedical, and environmental monitoring. Dielectrophoresis (DEP) is considered to be an ideal technique to manipulate bioparticles. The objective of this study is to develop a DEP microfluidic device that can trap fluorescent beads, which mimic bioparticles, at the low voltage and frequency of the sinusoidal signal supplied to the microfluidic device. Methods: A DEP microfluidic device, which is composed of polydimethylsiloxane (PDMS) channels and interdigitated electrode networks, is fabricated to trap fluorescent beads. The geometry of the interdigitated electrodes is determined through computational simulation. To determine the optimum voltage and frequency of the sinusoidal signal supplied to the device, the experiments of trapping beads are conducted at various combinations of voltage and frequency. The performance of the DEP microfluidic device is evaluated by investigating the correlation between fluorescent intensities and bead concentrations. Results: The optimum ratio of the widths between the negative and positive electrodes was 1:4 () at a gap of between the two electrodes. The DEP electrode networks were fabricated based on this geometry and used for the bead trapping experiments. The optimum voltage and frequency of the supplied signal for trapping fluorescent beads were 15 V and 5 kHz, respectively. The fluorescent intensity of the trapped beads increased linearly as the bead concentration increased. The coefficient of determination () between the fluorescent intensity and the bead concentration was 0.989. Conclusions: It is concluded that the microfluidic device developed in this study is promising for trapping bioparticles, such as a cell or virus, if they are conjugated to beads, and their concentration is quantified.
- Published
- 2016
34. Power Transmission Efficiency Analysis of 42 kW Power Agricultural Tractor According to Tillage Depth during Moldboard Plowing
- Author
-
Yong-Joo Kim, Md. Abu Ayub Siddique, Sang-Dae Lee, Yeon-Soo Kim, Seong-Un Park, Dong-Hyuck Hong, Kyeong-Hwan Lee, Seung-Yun Baek, Wan-Soo Kim, Seungmin Baek, and Su-Hwan Cheon
- Subjects
Tractor ,business.product_category ,Agricultural engineering ,01 natural sciences ,lcsh:Agriculture ,Plough ,fuel efficiency ,Thrust specific fuel consumption ,Power transmission ,Agricultural machinery ,business.industry ,010401 analytical chemistry ,lcsh:S ,power transmission efficiency ,04 agricultural and veterinary sciences ,0104 chemical sciences ,Tillage ,040103 agronomy & agriculture ,Fuel efficiency ,0401 agriculture, forestry, and fisheries ,Hardpan ,Environmental science ,moldboard plowing ,business ,tillage depth ,Agronomy and Crop Science ,agricultural tractor ,power requirements - Abstract
In order to optimize tractor design and optimize efficiency during tillage operation, it is essential to verify the impact through field tests on factors affecting the tractor load. The objectives of this study were to investigate the effect of tillage depth on power transmission efficiency of 42 kW power agricultural tractor during moldboard plowing. A load measurement system and a tillage depth measurement system were configured for field tests. To analyze the effect of tillage depth on power transmission efficiency and fuel consumption, the data measured in the three-repeated field test were classified according to tillage depth. As the tillage depth increased from 11 cm at the top of the hardpan to 23 cm at the deepest, the required power of the engine increased by approximately 13% from 35.48 kW to 40.11 kW, and the power transmission efficiency also increased significantly from 66% to 95%. Among them, the power transmission efficiency of the rear axle was significantly increased from 38% to 59%, which was the most affected. As the tillage depth increased, the overall power requirement is greatly increased due to the resulting workload, but the fuel consumption and the specific fuel consumption are reduced because the engine speed of the tractor is reduced. As the tillage depth increased from 11 cm to 23 cm, the fuel consumption rate was rather reduced by 13.5% as the engine rotational speed decreased 11.3% due to the increase work load of tractor. In addition, the specific fuel consumption decreased from 302.44 g/kWh to 236.93 g/kWh, showing a fuel consumption saving of up to 21.7% during moldboard plow. In addition, as the tillage depth increased, the ratio of the value excluding the mechanical and hydraulic power requirements has significantly decreased from 34% to 5% as the power transmission efficiency increases. This study considers the soil properties according to the soil depth, as well as the power transmission efficiency and fuel consumption rate. The research results can provide useful information for research on power transmission efficiency and selection of an appropriate power source of agricultural tractor according to tillage depth during moldboard plowing and are expected to be used in various ways as basic studies of digital farming research in agricultural machinery.
- Published
- 2020
35. Arabidopsis Basic Helix-Loop-Helix 34 (bHLH34) Is Involved in Glucose Signaling through Binding to a GAGA Cis-Element
- Author
-
Hyun-Woo Ju, Cheol Soo Kim, Kyeong-Hwan Lee, Ji-Hee Min, Dayoung Yoon, and Sungbeom Lee
- Subjects
0106 biological sciences ,0301 basic medicine ,Regulator ,macromolecular substances ,Plant Science ,lcsh:Plant culture ,01 natural sciences ,activator ,03 medical and health sciences ,chemistry.chemical_compound ,Transcription (biology) ,Arabidopsis ,lcsh:SB1-1110 ,Transcription factor ,Gene ,Abscisic acid ,transcription factor ,Original Research ,bHLH34 ,biology ,Basic helix-loop-helix ,Chemistry ,fungi ,AtPGR ,food and beverages ,Promoter ,biology.organism_classification ,Cell biology ,carbohydrates (lipids) ,030104 developmental biology ,glucose-responsive element ,lipids (amino acids, peptides, and proteins) ,010606 plant biology & botany - Abstract
The modulation of glucose (Glc) homeostasis and signaling is crucial for plant growth and development. Nevertheless, the molecular signaling mechanism by which a plant senses a cellular Glc level and coordinates the expression of Glc-responsive genes is still incompletely understood. Previous studies have shown that Arabidopsis thaliana plasma membrane Glc-responsive regulator (AtPGR) is a component of the Glc-responsive pathway. Here, we demonstrated that a transcription factor bHLH34 binds to 5′-GAGA-3′ element of the promoter region of AtPGR in vitro, and activates beta-glucuronidase (GUS) activity upon Glc treatment in AtPGR promoter-GUS transgenic plants. Gain- and loss-of-function analyses suggested that the bHLH34 involved in the responses to not only Glc, but also abscisic acid (ABA) and salinity. These results suggest that bHLH34 functions as a transcription factor in the Glc-mediated stress responsive pathway as well as an activator of AtPGR transcription. Furthermore, genetic experiments revealed that in Glc response, the functions of bHLH34 are different from that of a bHLH104, a homologue of bHLH34. Collectively, our findings indicate that bHLH34 is a positive regulator of Glc, and may affect ABA or salinity response, whereas bHLH104 is a negative regulator and epistatic to bHLH34 in the Glc response.
- Published
- 2017
- Full Text
- View/download PDF
36. Analysis of the PTO load of a 75kW agricultural tractor during rotary tillage and baler operation in Korean upland fields
- Author
-
Kyeong-Hwan Lee, Sun-Ok Chung, Dae-Hyun Lee, Yong-Joo Kim, Changhyun Choi, and Beom-Soo Shin
- Subjects
Engineering ,business.industry ,Mechanical Engineering ,Control engineering ,Rotational speed ,Tillage ,Breakage ,Ground speed ,Load spectrum ,Torque ,Life test ,business ,Agricultural tractor ,Marine engineering - Abstract
In this paper, the PTO severeness of an agricultural tractor during rotary tillage and baler operation was analyzed. The S–N curves of the PTO driving gears were obtained through fatigue life test. To obtain the S–N curves of the PTO driving gears, the breakage time and rotational speed of the gears were measured through observation of the bending stress with changing torque. The torque acting on the PTO was measured and analyzed during rotary tillage and baler operation. Rotary tillage and baler operation were conducted at two ground speeds and two PTO rotational speeds at upland field sites with similar soil conditions, respectively. The load data were inverted to a load spectrum using rain-flow counting and SWT equations. Modified Miner’s rule was used to calculate the partial damage sum. The severeness was defined as the relative ratio of the damage sum. The results showed that the damage of the PTO increased when the ground speed or the PTO rotational speed increased. The effect of the PTO rotational speed on the severeness of the PTO was more significant than that of the ground speed. The severeness of the PTO of rotary tillage was greater than that of baler operation.
- Published
- 2015
37. Abscisic acid receptor PYRABACTIN RESISTANCE-LIKE 8, PYL8, is involved in glucose response and dark-induced leaf senescence in Arabidopsis
- Author
-
Kyeong-Hwan Lee, Ha-Nul Lee, and Cheol Soo Kim
- Subjects
Senescence ,Arabidopsis ,Biophysics ,Naphthalenes ,Genes, Plant ,Biochemistry ,chemistry.chemical_compound ,Plant Growth Regulators ,Gene Expression Regulation, Plant ,Stress, Physiological ,RNA interference ,Hexokinase ,RNA, Messenger ,Receptor ,Molecular Biology ,Abscisic acid ,Pyrabactin ,Sulfonamides ,biology ,Arabidopsis Proteins ,fungi ,food and beverages ,Cell Biology ,Darkness ,Plants, Genetically Modified ,biology.organism_classification ,Plant Leaves ,carbohydrates (lipids) ,Basic-Leucine Zipper Transcription Factors ,Glucose ,chemistry ,RNA, Plant ,RNA Interference ,Signal transduction ,Abscisic Acid ,Signal Transduction - Abstract
Abscisic acid (ABA) receptors in plants are thought to be involved in various cellular processes mediated by signal transduction pathways. There are about 14 ABA receptors in Arabidopsis, but only a few have been studied. In this study, we investigated the effect of the disruption and overexpression of an ABA receptor gene, PYL8 (At5g53160) on plant responses to glucose (Glc) and dark-induced leaf senescence. Expression of PYL8 was strongly reduced by Glc treatment. Overexpression of PYL8 in Arabidopsis resulted in significantly reduced seed germination and cotyledon greening under high Glc conditions, while RNAi transgenic lines were more insensitive to Glc stress. Activities of two Glc-responsive genes, Arabidopsis thaliana Hexokinase 1 (AtHXK1) and ABA insensitive 5 (ABI5) were higher in PYL8-overexpressing plants than in the wild-type (WT) plants after Glc treatment, whereas the transcript levels of these genes in RNAi plants decreased. Furthermore, PYL8-overexpressing plants displayed increased yellowing, membrane ion leakage, and reduced chlorophyll content due to dark-induced senescence, and exhibited stronger expression of a group of senescence-inducible genes than did WT. The data show that PYL8 plays essential roles in responses to both Glc and dark-induced senescence in A. thaliana.
- Published
- 2015
38. Path planning for autonomous lawn mower tractor
- Author
-
Md. Shaha Nur Kabir, Jong-Kyou Ha, Sun-Ok Chung, Kyeong-Hwan Lee, Yong-Joo Kim, and Ming-Zhang Song
- Subjects
Tractor ,business.product_category ,Software ,Computer science ,business.industry ,Path (graph theory) ,Mower ,Measure (physics) ,Global Positioning System ,Motion planning ,business ,Automotive engineering ,Test data - Abstract
Path planning is an essential part for traveling and mowing of autonomous lawn mower tractors. Objectives of the paper were to analyze operation patterns by a skilled farmer, to extract and optimize waypoints, and to demonstrate generation of formatted planned path for autonomous lawn mower tractors. A 27-HP mower tractor was operated by a skilled farmer on grass fields. To measure tractor travel and operation characteristics, an RTK-GPS antenna with a 6-cm RMS error, an inertia motion sensing unit, a gyro compass, a wheel angle sensor, and a mower on/off sensor were mounted on the mower tractor, and all the data were collected at a 10-Hz rate. All the sensor data were transferred through a software program to show the status immediately on the notebook. Planned path was generated using the program parameter settings, mileage and time calculations, and the travel path was plotted using developed software. Based on the human operation patterns, path planning algorithm was suggested for autonomous mower tractor. Finally path generation was demonstrated in a formatted file and graphic display. After optimizing the path planning, a decrease in distance about 13% and saving of the working time about 30% was achieved. Field test data showed some overlap, especially in the turning areas. Results of the study would be useful to implement an autonomous mower tractor, but further research needs to improve the performance.
- Published
- 2015
39. Pre-processing of load data of agricultural tractors during major field operations
- Author
-
Myong-Jin Ryu, Yong-Joo Kim, Jong-Kyou Ha, Sun-Ok Chung, Youn-Kug Choo, Kyeong-Hwan Lee, and Md. Shaha Nur Kabir
- Subjects
Plough ,Tillage ,Loader ,Axle ,Power transmission ,business.product_category ,Agricultural machinery ,business.industry ,Torque ,Environmental science ,Rotational speed ,business ,Automotive engineering - Abstract
Development of highly efficient and energy-saving tractors has been one of the issues in agricultural machinery. For design of such tractors, measurement and analysis of load on major power transmission parts of the tractors are the most important pre-requisite tasks. Objective of this study was to perform pre-processing procedures before effective analysis of load data of agricultural tractors (30, 75, and 82 kW) during major field operations such as plow tillage, rotary tillage, baling, bale wrapping, and to select the suitable pre-processing method for the analysis. A load measurement systems, equipped in the tractors, were consisted of strain-gauge, encoder, hydraulic pressure, and radar speed sensors to measure torque and rotational speed levels of transmission input shaft, PTO shaft, and driving axle shafts, pressure of the hydraulic inlet line, and travel speed, respectively. The entire sensor data were collected at a 200-Hz rate. Plow tillage, rotary tillage, baling, wrapping, and loader operations were selected as major field operations of agricultural tractors. Same or different farm works and driving levels were set differently for each of the load measuring experiment. Before load data analysis, pre-processing procedures such as outlier removal, low-pass filtering, and data division were performed. Data beyond the scope of the measuring range of the sensors and the operating range of the power transmission parts were removed. Considering engine and PTO rotational speeds, frequency components greater than 90, 60, and 60 Hz cut off frequencies were low-pass filtered for plow tillage, rotary tillage, and baler operations, respectively. Measured load data were divided into five parts: driving, working, implement up, implement down, and turning. Results of the study would provide useful information for load characteristics of tractors on major field operations.
- Published
- 2015
40. Parallel in/out systolic AB 2 architecture with low complexity in GF (2 m )
- Author
-
Seong-Ho Choi and Kyeong-Hwan Lee
- Subjects
Low complexity ,Multiplier (economics) ,Parallel computing ,Hardware_ARITHMETICANDLOGICSTRUCTURES ,Electrical and Electronic Engineering ,Architecture ,GF(2) ,Mathematics - Abstract
Efficient GF(2 m ) arithmetic clearly affects the performance of compute-intensive applications. A new low-complexity parallel-in/out systolic AB 2 multiplier based on the least significant bit-first scheme is presented. Compared with related works, the scheme yields significantly lower area-time complexity.
- Published
- 2016
41. Loss of Ribosomal Protein L24A (RPL24A) suppresses proline accumulation of Arabidopsis thaliana ring zinc finger 1 (atrzf1) mutant in response to osmotic stress
- Author
-
Kyeong-Hwan Lee, Moon-Soo Chung, Cheol Soo Kim, Sungbeom Lee, and Seung-Hyeon Park
- Subjects
0106 biological sciences ,0301 basic medicine ,Ribosomal Proteins ,Osmosis ,Osmotic shock ,Proline ,Mutant ,Biophysics ,Arabidopsis ,Down-Regulation ,01 natural sciences ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Ribosomal protein ,Osmotic Pressure ,Stress, Physiological ,Arabidopsis thaliana ,Molecular Biology ,Abscisic acid ,Suppressor mutation ,biology ,Abiotic stress ,Arabidopsis Proteins ,Cell Biology ,biology.organism_classification ,Droughts ,030104 developmental biology ,chemistry ,Mutation ,010606 plant biology & botany - Abstract
Proline (Pro) metabolism in plants is involved in various cellular processes mediated during abiotic stress. However, the Pro-regulatory mechanisms are unclear. We used a suppressor mutation technique to isolate novel genes involved in the regulation of Pro metabolism in Arabidopsis. Using atrzf1 as a parental plant for T-DNA tagging mutagenesis, we identified a suppressor mutant, termed proline content alterative 21 (pca21), that displayed reduced Pro contents compared with the atrzf1 under osmotic stress conditions. Genomic Thermal Asymmetric Interlaced (TAIL)-PCR revealed pca21 harbored an inserted T-DNA in the region of At2g36620 that encodes Ribosomal Protein L24A. In general, the pca21 mutant partially suppressed the insensitivity of atrzf1 to osmotic stress and abscisic acid during seed germination and early seedling stage. Additionally, the pca21 mutant had increased MDA content and lower expression of several Pro biosynthesis-related genes than the atrzf1 mutant during drought condition. These results suggest that pca21 acts as partial suppressor of atrzf1 in the osmotic stress response through the Pro-mediated pathway.
- Published
- 2017
42. Reduced Expression of Gongdae Ring Zinc Finger 1 (GdRZF1) Enhances Drought Stress Tolerance in Watermelon (Citrullus lanatus)
- Author
-
Kyeong-Hwan Lee, Jung-Sung Chung, Sungbeom Lee, Ji-Hee Min, Kwang-Hyun Min, Cheol Soo Kim, and Seung-Hyeon Park
- Subjects
Zinc finger ,Drought stress ,Citrullus lanatus ,biology ,Botany ,Horticulture ,biology.organism_classification ,Ring (chemistry) - Published
- 2017
43. Development of Environment Monitoring System for Crop Growth Measurement
- Author
-
Du-Han Kim, Yong-Joo Kim, Changhyun Choi, Sun-Ok Chung, Tae-Hyun Choi, and Kyeong-Hwan Lee
- Subjects
Agricultural science ,Crop growth ,Environmental science ,Monitoring system ,Agricultural engineering - Published
- 2017
44. The CONSTANS-like 4 transcription factor, AtCOL4, positively regulates abiotic stress tolerance through an abscisic acid-dependent manner in Arabidopsis
- Author
-
Ji-Hee Min, Kyeong-Hwan Lee, Jung-Sung Chung, and Cheol Soo Kim
- Subjects
Zinc finger ,food.ingredient ,biology ,Osmotic shock ,Abiotic stress ,fungi ,food and beverages ,Plant Science ,biology.organism_classification ,Biochemistry ,General Biochemistry, Genetics and Molecular Biology ,chemistry.chemical_compound ,food ,chemistry ,Arabidopsis ,Arabidopsis thaliana ,Abscisic acid ,Transcription factor ,Cotyledon - Abstract
The precise roles of the B-box zinc finger family of transcription factors in plant stress are poorly understood. Functional analysis was performed on AtCOL4, an Arabidopsis thaliana L. CONSTANS-like 4 protein that is a putative novel transcription factor, and which contains a predicted transcriptional activation domain. Analyses of an AtCOL4 promoter-β-glucuronidase (GUS) construct revealed substantial GUS activity in whole seedlings. The expression of AtCOL4 was strongly induced by abscisic acid (ABA), salt, and osmotic stress. Mutation in atcol4 resulted in increased sensitivity to ABA and salt stress during seed germination and the cotyledon greening process. In contrast, AtCOL4-overexpressing plants were less sensitive to ABA and salt stress compared to the wild type. Interestingly, in the presence of ABA or salt stress, the transcript levels of other ABA biosynthesis and stress-related genes were enhanced induction in AtCOL4-overexpressing and WT plants, rather than in the atcol4 mutant. Thus, AtCOL4 is involved in ABA and salt stress response through the ABA-dependent signaling pathway. Taken together, these findings provide compelling evidence that AtCOL4 is an important regulator for plant tolerance to abiotic stress.
- Published
- 2014
45. Patent Trend of Unmanned and Automated Agricultural Production - Open Field Operation
- Author
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ChoongHan Lee, Sun-Ok Chung, Dae-Hyun Lee, Yongjoo Kim, and Kyeong-Hwan Lee
- Subjects
Engineering ,business.industry ,Operations management ,General Medicine ,Agricultural productivity ,business ,Manufacturing engineering - Published
- 2014
46. Detection of proline using a novel paper-based analytical device for on-site diagnosis of drought stress in plants
- Author
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Kyeong-Hwan Lee, Cheol Soo Kim, Young-Soo Choi, and Mi Rha Lee
- Subjects
Paper ,Drought stress ,Proline ,Arabidopsis ,01 natural sciences ,010305 fluids & plasmas ,chemistry.chemical_compound ,Stress, Physiological ,Lab-On-A-Chip Devices ,0103 physical sciences ,Instrumentation ,010302 applied physics ,Detection limit ,Dehydration ,Ninhydrin ,food and beverages ,Equipment Design ,Paper based ,Microfluidic Analytical Techniques ,Droughts ,chemistry ,Green color ,Biological system ,Biosensor - Abstract
We developed and characterized a paper-based microfluidic sensor for the on-site diagnosis of drought stress in plants. Proline was used as a biomarker for analyzing drought stress, which was extracted by a colorimetric method using the proline-ninhydrin reaction. Paper was used as the main sensor material for the on-site detection of proline as it is easily transportable and cost-effective. The paper-based sensor was fabricated using wax-printing and origami methods, and the sensor was precoated with ninhydrin to allow for easy and convenient on-site use. Furthermore, a sample-to-ninhydrin ratio of 1:2 was found to confer optimal sensitivity to the drought diagnosis sensor. The concentration of proline in a sample was quantified by red-green-blue analysis to determine the change in green color intensity levels in response to distinct proline concentrations, which were detected by the sensor. The limit of detection of proline using the devised sensor was 657 µM, and the green color intensity level decreased with increasing proline concentration. In addition, the sensor was validated in an experimental drought stress model with Arabidopsis and subjected to drought stress for 21 days, and the amount of proline detected was 10 mM. The devised paper-based microfluidic sensor highlights the possibility of the on-site evaluation of drought stress in plants with potential to be utilized in various agricultural areas in the future.
- Published
- 2019
47. Development of Path Planning Algorithm for an Autonomous Mower Tractor
- Author
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Yong-Joo Kim, Ming-Zhang Song, Kyeong-Hwan Lee, Dae-Hyun Lee, Young-Seok Chae, Seung-Hwa Yu, Sin-Woo Kang, Sun-Ok Chung, and Ki-Dae Kim
- Subjects
Tractor ,Engineering ,business.product_category ,business.industry ,Mower ,General Medicine ,Field (computer science) ,law.invention ,Data point ,law ,Path (graph theory) ,Gyrocompass ,Motion planning ,business ,Algorithm ,Simulation ,Test data - Abstract
Path planning is an essential part for autonomous mower tractor to travel and mow. Objectives of the paper were to analyze operation patterns by a farmer, to extract and optimize waypoints, and to demonstrate generation of formatted planned path for autonomous mower tractors. An 18-kW mid-mower tractor was operated by a skilled farmer on grass fields. To measure tractor travel and operation characteristics, an RTK-GPS antenna with a 2-cm RMS error, an inertia motion sensing unit, a gyro compass, a wheel angle sensor, and a mower on/off sensor were mounted on the mower tractor, and all the data were collected at a 10-Hz rate. And all of sensor data were transferred through a program to show the status immediately on the notebook. From 3 grass field tests, total 53,412 data points (every 0.1s) were obtained, and amount the data 73% was straight steering, 22% was turning steering, and 5% was for others (e.g. artificial error, needless work). Field test data showed some overlap, especially in the turning areas. Based on the human operation patterns, path planning algorithm was suggested for autonomous mower tractor. Finally path generation was demonstrated in a formatted file and graphic display. Results of the study would be useful to implement and test autonomous mower tractor, but further research needs to be done to improve the performance.
- Published
- 2013
48. Rapid Detection of Norovirus from Fresh Lettuce Using Immunomagnetic Separation and a Quantum Dots Assay
- Author
-
Jong-Soon Choi, Duwoon Kim, Sung Yang, Sang-Mu Ko, Kyeong-Hwan Lee, Joseph Kwon, Se-Young Cho, Hee-Min Lee, and Jae-Keun Chung
- Subjects
Analyte ,Time Factors ,Serial dilution ,viruses ,Colony Count, Microbial ,Food Contamination ,Polyethylene glycol ,Biology ,medicine.disease_cause ,Immunomagnetic separation ,Sensitivity and Specificity ,Microbiology ,Virus ,chemistry.chemical_compound ,Quantum Dots ,medicine ,Humans ,Centrifugation ,Chromatography ,Immunomagnetic Separation ,Elution ,Norovirus ,Lettuce ,Molecular biology ,chemistry ,Consumer Product Safety ,Food Microbiology ,Food Science - Abstract
Current molecular methods that include PCR have been used to detect norovirus in many food samples. However, the protocols require removing PCR inhibitors and incorporate time-consuming concentration steps to separate virus from analyte for rapid and sensitive detection of norovirus. We developed an immunomagnetic separation (IMS) and a quantum dots (QDs) assay to detect norovirus eluted from fresh lettuce with Tris buffer containing 1% beef extract (pH 9.5). IMS facilitated viral precipitation with a 10-min incubation, whereas virus concentration using polyethylene glycol (PEG) requires more than 3 h and an additional high-speed centrifugation step to precipitate virus before reverse transcription PCR (RT-PCR) analysis. The fluorescence intensity of QDs was detected qualitatively on norovirus dilutions of 10(-1) to 10(-3) in a stool suspension (100 RT-PCR units/ml). The results suggest that a fluorescence assay based on IMS and QDs is valid for detecting norovirus qualitatively according to fluorescent signal intensity within the same virus detection limit produced by IMS-RT-PCR and PEG-RT-PCR.
- Published
- 2013
49. Adaptive Watermarking for MP3 Copyright Protections Using Psychological Acoustics
- Author
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Kyeong-Hwan Lee
- Subjects
Engineering ,Acoustics and Ultrasonics ,business.industry ,Applied Mathematics ,Speech recognition ,Acoustics ,Data_MISCELLANEOUS ,Dct transform ,Watermark ,Spread spectrum ,Speech and Hearing ,Compression (functional analysis) ,Signal Processing ,business ,Instrumentation ,Digital watermarking - Abstract
In this paper, we suggest a new audio watermarking method for audio contents copyrights that can efficiently provide protection from MP3 compression attacks. Watermarks were inserted at the coefficients repeatedly from low frequencies to high frequencies after DCT transform in commonly used Cox`s spread spectrum method. Because the methods using arbitrary coefficients are not effective, we use the new weight functions that make small losses for the watermark coefficients during attacks, using psychological acoustics. In the results of various sound clips, the suggested method had overall better outcomes than the Cox`s method by preserving watermarks and reducing distortions of the original sounds.
- Published
- 2013
50. Melon Surface Color and Texture Analysis for Estimation of Soluble Solids Content and Firmness
- Author
-
Young-Soo Choi, Kyeong Hwan Lee, Seung Hwa Yu, Soo Nam Yoo, Hwa Sun Shin, and Sang Ryong Suh
- Subjects
Horticulture ,Geography ,Soluble solids ,Melon ,Mechanical Engineering ,Content (measure theory) ,Partial least squares regression ,Engineering (miscellaneous) ,Agricultural and Biological Sciences (miscellaneous) ,Texture (geology) ,Computer Science Applications ,Internal quality - Abstract
Purpose: The net rind pattern and color of melon surface are important for a high market value of melon fruits. The development of the net and color are closely related to the changes in shape, size, and maturing. Therefore, the net and color characteristics can be used indicators for assessment of melon quality. The goal of this study was to investigate the possibility of estimating melon soluble solids content (SSC) and firmness by analyzing the net and color characteristics of fruit surface. Methods: The true color images of melon surface obtained at fruit equator were analyzed with 18 color features and 9 texture features. The partial least squares (PLS) method was used to estimate SSC and firmness in melons using their color and texture features. Results: In sensing melon SSC, the coefficients of determination of validation (Rv 2) of the prediction models using the color and texture features were 0.84 (root mean square error of validation, RMSEV: 1.92 °Brix) and 0.96 (RMSEV: 0.60 °Brix), respectively. The Rv 2 values of the models for predicting melon firmness using the color and texture features were 0.64 (RMSEV: 4.62 N) and 0.79 (RMSEV: 2.99 N), respectively. Conclusions: In general, the texture features were more useful for estimating melon internal quality than the color features. However, to strengthen the usefulness of the color and texture features of melon surface for estimation of melon quality, additional experiments with more fruit samples need to be conducted.
- Published
- 2012
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