60 results on '"Daeun Choi"'
Search Results
2. 3-D Numerical Simulation and Optical Diagnosis of Temperature Distribution Inside a Chamber of Hot Filament Chemical Vapor Deposition
- Author
-
Daeun Choi, Yong Hee Lee, Kwang Ho Kim, and Sooseok Choi
- Subjects
Materials Science (miscellaneous) ,General Medicine ,Electrical and Electronic Engineering ,Physical and Theoretical Chemistry ,Condensed Matter Physics - Published
- 2023
- Full Text
- View/download PDF
3. Dysregulated MicroRNAs in the Pathogenesis of Systemic Lupus Erythematosus: A Comprehensive Review
- Author
-
Daeun Choi, Jimin Kim, Jae Won Yang, Ji Hong Kim, Seoyeon Park, and Jae Il Shin
- Subjects
Cell Biology ,Molecular Biology ,Applied Microbiology and Biotechnology ,Ecology, Evolution, Behavior and Systematics ,Developmental Biology - Published
- 2023
- Full Text
- View/download PDF
4. Surch: Enabling Structural Search and Comparison for Surgical Videos
- Author
-
Jeongyeon Kim, Daeun Choi, Nicole Lee, Matt Beane, and Juho Kim
- Published
- 2023
- Full Text
- View/download PDF
5. An Analysis of the Influence of Neighborhood Environment Characteristics on Walking Activity and Health Perception of the Elderly by Walking Purpose : Focusing on Bulkwang 2-dong in Seoul
- Author
-
Daeun Choi, Juyoung Park, and Jahoon Koo
- Published
- 2022
- Full Text
- View/download PDF
6. Sensitivity examination of YOLOv4 regarding test image distortion and training dataset attribute for apple flower bud classification
- Author
-
Wenan Yuan, Daeun Choi, Dimitrios Bolkas, Paul Heinz Heinemann, and Long He
- Subjects
General Earth and Planetary Sciences - Published
- 2022
- Full Text
- View/download PDF
7. An Apple Tree Branch Pruning Analysis
- Author
-
Azlan Zahid, Md Sultan Mahmud, Long He, James Schupp, Daeun Choi, and Paul Heinemann
- Subjects
robotic pruning ,branch cutting ,pruning end-effector ,automated pruning ,cutting angle ,pruning torque ,Plant culture ,branch diameter ,pruning force ,Horticulture ,malus ×domestica ,SB1-1110 - Published
- 2022
- Full Text
- View/download PDF
8. Development of an Automatic Airflow Control System for Precision Sprayers Based on Tree Canopy Density
- Author
-
Md Sultan Mahmud, Azlan Zahid, Long He, Heping Zhu, Daeun Choi, Grzegorz Krawczyk, and Paul Heinemann
- Subjects
Biomedical Engineering ,Soil Science ,Forestry ,Agronomy and Crop Science ,Food Science - Abstract
Highlights A LiDAR-guided automatic airflow control system for precision sprayers was developed. Three models were built to measure the amount of airflow required for apple trees. The study confirmed that adjusting the fan inlet could control airflow penetration into tree canopies. Results suggest that the system can reduce spray drift and off-target losses. Abstract. The airflow discharged from orchard airblast sprayers is a primary component for successfully carrying spray droplets to the target trees. Because of the variation in orchard tree canopies, control of the airflow to minimize off-target loss during spray application is essential. An automatic airflow control system for precision sprayers was developed to maximize spray droplet coverage on targets and minimize off-target loss while considering the tree canopy densities. The primary component of the system was an iris damper, which was designed as a retrofit attachment on the fan inlet of a three-point airblast intelligent sprayer. A 3D light detection and ranging (LiDAR) sensor was installed at the top of the sprayer to acquire the tree canopy data. A motor was employed to control the damper opening with a micro-controller. To develop the models required for automatic airflow control, field experiments were conducted at three canopy density orchards with different cultivars (GoldRush, Gala, and Fuji). A total of 15 trees (five trees from each cultivar) were randomly selected, and five different damper openings (openings 1, 2, 3, 4, and 5) were tested for each tree. Opening 1 represented the same air inlet as a traditional precision airblast sprayer, while openings 2, 3, 4, and 5 were the sequentially reduced air inlets of the sprayer. A canopy density measurement algorithm was scripted to measure the canopy point density of individual trees. Three models were built to show relationships between (1) tree canopy point densities and airflows; (2) canopy densities and damper openings; and (3) damper opening and motor steps. The combination of the two models (2 & 3) was used to assess the amount of airflow required for a specific canopy density. Field validations for medium and high-density trees showed that the system achieved adequate spray penetration at the top, middle, bottom, back-left, and back-right positions of the tree sections and reduced off-target loss at the ground and edge of next row sections using openings 4 and 2, respectively. However, the mechanical motion of the damper required 3 s to move from minimum to maximum opening, so the average canopy density was recommended to control the airflow. The overall results suggested that the automatic airflow control system could reduce spray drift and off-target losses and improve spray application efficiency in orchards. Keywords: Automation, Canopy sensing, Fan inlet, Precision spraying, Variable rate application.
- Published
- 2022
- Full Text
- View/download PDF
9. Time-Weighted SAR in Rats for the Estimation of Practical RF Exposure in Reverberation Chambers
- Author
-
Sangbong Jeon, Daeun Choi, Seong Ju Kim, Ae-Kyoung Lee, Hyung-Do Choi, and Dongho Kim
- Subjects
General Computer Science ,General Engineering ,General Materials Science ,Electrical and Electronic Engineering - Published
- 2022
- Full Text
- View/download PDF
10. Identification of 1‐phenoxy‐3‐(piperazin‐1‐yl)propan‐2‐ol derivatives as novel triple reuptake inhibitors
- Author
-
Md. Ashrafuzzaman, Su Hyun Ji, Hyomin Ahn, Hwan Won Chung, Daeun Choi, Ju Jin Park, Minji Go, Jung In Pyo, Azam Sharif Mohammed Shafioul, Duck‐Hyung Lee, Sung‐Gil Chi, Chiman Song, Chan Seong Cheong, and Seo‐Jung Han
- Subjects
General Chemistry - Published
- 2023
- Full Text
- View/download PDF
11. Numerical Analysis of Thermal Flow Characteristics Inside Waste Combustion Chamber with Multiple Thermal Plasma Jets
- Author
-
Hyeokjun Kang, Jeong-Hwan Oh, Daeun Choi, Hidemasa Takana, and Sooseok Choi
- Subjects
Materials Science (miscellaneous) ,General Medicine ,Electrical and Electronic Engineering ,Physical and Theoretical Chemistry ,Condensed Matter Physics - Published
- 2021
- Full Text
- View/download PDF
12. Reflect, not Regret: Understanding Regretful Smartphone Use with App Feature-Level Analysis
- Author
-
Donghwi Kim, Hyunsung Cho, Eun Kyoung Choe, DaEun Choi, Wan Ju Kang, and Sung-Ju Lee
- Subjects
Computer Networks and Communications ,business.industry ,Computer science ,Control (management) ,Internet privacy ,Behavior change ,Regret ,Human-Computer Interaction ,Entertainment ,Intervention (counseling) ,Feature (machine learning) ,Social media ,Android (operating system) ,business ,Social Sciences (miscellaneous) - Abstract
Digital intervention tools against problematic smartphone usage help users control their consumption on smartphones, for example, by setting a time limit on an app. However, today's social media apps offer a mix of quasiessential and addictive features in an app (e.g., Instagram has following feeds, recommended feeds, stories, and direct messaging features), which makes it hard to apply a uniform logic for all uses of an app without a nuanced understanding of feature-level usage behaviors. We study when and why people regret using different features of social media apps on smartphones. We examine regretful feature uses in four smartphone social media apps (Facebook, Instagram, YouTube, and KakaoTalk) by utilizing feature usage logs, ESM surveys on regretful use collected for a week, and retrospective interviews from 29 Android users. In determining whether a feature use is regretful, users considered different types of rewards they obtained from using a certain feature (i.e., social, informational, personal interests, and entertainment) as well as alternative rewards they could have gained had they not used the smartphone (e.g., productivity). Depending on the types of rewards and the way rewards are presented to users, probabilities to regret vary across features of the same app. We highlight three patterns of features with different characteristics that lead to regretful use. First, "following"-based features (e.g., Facebook's News Feed and Instagram's Following Posts and Stories) induce habitual checking and quickly deplete rewards from app use. Second, recommendation-based features situated close to actively used features (e.g., Instagram's Suggested Posts adjacent to Search) cause habitual feature tour and sidetracking from the original intention of app use. Third, recommendation-based features with bite-sized contents (e.g., Facebook's Watch Videos) induce using "just a bit more," making people fall into prolonged use. We discuss implications of our findings for how social media apps and intervention tools can be designed to reduce regretful use and how feature-level usage information can strengthen self-reflection and behavior changes.
- Published
- 2021
- Full Text
- View/download PDF
13. Unmanned aerial vehicle based tree canopy characteristics measurement for precision spray applications
- Author
-
Md Sultan Mahmud, Long He, Paul Heinemann, Daeun Choi, and Heping Zhu
- Published
- 2023
- Full Text
- View/download PDF
14. Detection and infected area segmentation of apple fire blight using image processing and deep transfer learning for site-specific management
- Author
-
Md Sultan Mahmud, Long He, Azlan Zahid, Paul Heinemann, Daeun Choi, Grzegorz Krawczyk, and Heping Zhu
- Subjects
Forestry ,Horticulture ,Agronomy and Crop Science ,Computer Science Applications - Published
- 2023
- Full Text
- View/download PDF
15. Development of a Robotic Harvesting Mechanism for Button Mushrooms
- Author
-
Long He, Daeun Choi, Yaoming Li, John Pecchia, Xiaohu Jiang, and Mingsen Huang
- Subjects
Alternative methods ,Mushroom ,Computer science ,Biomedical Engineering ,Soil Science ,Forestry ,Suction cup ,Robot end effector ,Automotive engineering ,law.invention ,Bruise ,Mechanism (engineering) ,Stipe (mycology) ,law ,medicine ,Trimming ,medicine.symptom ,Agronomy and Crop Science ,Food Science - Abstract
HighlightsA robotic mushroom picking mechanism was developed, including positioning, picking, and stipe trimming.The picking end-effector was designed based on a bending motion around the stipe-substrate joint.The overall success rate of the developed picking mechanism reached 91.4%.Acting time and air pressure for the suction cup were studied in mushroom bruise level tests.Abstract. Button mushroom (Agaricus bisporus) harvesting mainly relies on costly manpower, which is time-consuming and labor-intensive. Robotic harvesting is an alternative method to address this challenge. In this study, a robotic mushroom picking mechanism was designed, including a picking end-effector based on a bending motion, a four degree-of-freedom (DoF) positioning end-effector for moving the picking end-effector, a mushroom stipe trimming end-effector, and an electro-pneumatic control system. A laboratory-scale prototype was fabricated to validate the performance of the mechanism. Bruise tests on the mushroom caps were also conducted to analyze the influence of air pressure and acting time of the suction cup on bruise level. The test results showed that the picking end-effector was successfully positioned to the target locations. The success rate of the picking end-effector was 90% at first pick and increased to 94.2% after second pick. The main reason for the failures was inclined growing condition of those mushrooms, resulting in difficulties in engaging the mushroom cap with the suction cup facing straight downward. The trimming end-effector achieved a success rate of 97% overall. The bruise tests indicated that the air pressure was the main factor affecting the bruise level, compared to the suction cup acting time, and an optimized suction cup may help to alleviate the bruise damage. The laboratory test results indicated that the developed picking mechanism has potential to be implemented in automatic mushroom harvesting. Keywords: Bruise test, End-effector, Mushroom, Robotic harvesting.
- Published
- 2021
- Full Text
- View/download PDF
16. Investigation of Branch Accessibility with a Robotic Pruner for Pruning Apple Trees
- Author
-
James R. Schupp, Long He, Paul Heinz Heinemann, Azlan Zahid, and Daeun Choi
- Subjects
Computer science ,Biomedical Engineering ,Soil Science ,Forestry ,Tree (graph theory) ,Path length ,Random tree ,Path (graph theory) ,Shortest path problem ,Pruning (decision trees) ,Motion planning ,Agronomy and Crop Science ,Algorithm ,Smoothing ,Food Science - Abstract
HighlightsA branch accessibility simulation was performed for robotic pruning of apple trees.A virtual tree environment was established using a kinematic manipulator model and an obstacle model.Rapidly-exploring random tree (RRT) was combined with smoothing and optimization for improved path planning.Effects on RRT path planning of the approach angle of the end-effector and cutter orientation at the target were studied.Abstract. Robotic pruning is a potential solution to reduce orchard labor and associated costs. Collision-free path planning of the manipulator is essential for successful robotic pruning. This simulation study investigated the collision-free branch accessibility of a six rotational (6R) degrees of freedom (DoF) robotic manipulator with a shear cutter end-effector. A virtual environment with a simplified tall spindle tree canopy was established in MATLAB. An obstacle-avoidance algorithm, rapidly-exploring random tree (RRT), was implemented for establishing collision-free paths to reach the target pruning points. In addition, path smoothing and optimization algorithms were used to reduce the path length and calculate the optimized path. Two series of simulations were conducted: (1) performance and comparison of the RRT algorithm with and without smoothing and optimization, and (2) performance of collision-free path planning considering different approach poses of the end-effector relative to the target branch. The simulations showed that the RRT algorithm successfully avoided obstacles and allowed the manipulator to reach the target point with 23 s average path finding time. The RRT path length was reduced by about 28% with smoothing and by 25% with optimization. The RRT smoothing algorithm generated the shortest path lengths but required about 1 to 3 s of additional computation time. The lowest coefficient of variation and standard deviation values were found for the optimization method, which confirmed the repeatability of the method. Considering the different end-effector approach poses, the simulations suggested that successfully finding a collision-free path was possible for branches with no existing path using the ideal (perpendicular cutter) approach pose. This study provides a foundation for future work on the development of robotic pruning systems. Keywords: Agricultural robotics, Collision-free path, Manipulator, Path planning, Robotic pruning, Virtual tree environment.
- Published
- 2021
- Full Text
- View/download PDF
17. Stylette: Styling the Web with Natural Language
- Author
-
Tae Soo Kim, DaEun Choi, Yoonseo Choi, and Juho Kim
- Published
- 2022
- Full Text
- View/download PDF
18. Development of a Robotic End-Effector for Apple Tree Pruning
- Author
-
Daeun Choi, Lihua Zeng, Azlan Zahid, Paul Heinz Heinemann, Long He, and James R. Schupp
- Subjects
0209 industrial biotechnology ,Computer science ,Biomedical Engineering ,Soil Science ,Apple tree ,ComputerApplications_COMPUTERSINOTHERSYSTEMS ,02 engineering and technology ,Workspace ,law.invention ,020901 industrial engineering & automation ,law ,Simulation ,business.industry ,Forestry ,Robotics ,04 agricultural and veterinary sciences ,Robot end effector ,Tree (data structure) ,Control system ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Pneumatic cylinder ,Artificial intelligence ,business ,Agronomy and Crop Science ,Pruning ,Food Science - Abstract
HighlightsAn end-effector with two degrees of freedom (2R) was developed for pruning apple trees.A rational 2×2 relationship (R2 = 0.93) was found for ‘Fuji’ apple tree branch diameter and cutting force.Simulation showed that the cutter can be aligned in a wide range of orientations in a spherical workspace.The developed end-effector was able to cut branches up to 12 mm in diameter.Abstract. Robotics and automation technologies are now used extensively in agriculture, while production operations for tree fruit crops still largely depend on manual labor. Manual pruning is a labor-intensive and costly task in apple production. Robotic pruning is a potential solution, but it involves several challenges due to the unstructured work environment. This study focused on designing an end-effector prototype for pruning considering the maneuvering, spatial, mechanical, and horticultural requirements. Branch cutting force was measured with a thin force sensor to provide guidelines for the end-effector design. The test results indicated the relationship between the force required to cut different diameter branches with an R2 value of 0.93. The end-effector was developed using two rotary motors, a pneumatic cylinder, and a pair of bypass shear blades. A three-directional linear manipulator system and a control system were built for moving the end-effector to targeted locations. A mathematical model was developed for simulation of the workspace utilization and reachable points of the end-effector. The simulation results indicated that the end-effector can be aligned in a wide range of orientations of the cutter. Field tests were conducted for validation of the simulation results and performance assessment of the end-effector. The results indicated that the end-effector with the current parameter settings successfully cut branches up to 12 mm in diameter and was able to cut branches in a wide range of possible orientations in a given 3D space. The robotic end-effector developed in this study is a core component of an automated pruning system for fruit trees. In future work, an integrated manipulator system will be developed for branch accessibility with collision-free trajectories. Keywords: Malus × domestica (Borkh.), Pruning end-effector, Reachable-points simulation, Tree pruning.
- Published
- 2020
- Full Text
- View/download PDF
19. Thermal Properties of ‘Gala’ Apples during Growing Season for Predicting Harvest Time
- Author
-
Daeun Choi, Oznur Caliskan-Aydogan, Paul Heinz Heinemann, Hojae Yi, Virendra M. Puri, and James R. Schupp
- Subjects
Horticulture ,Harvest time ,Biomedical Engineering ,Soil Science ,Environmental science ,Growing season ,Forestry ,Agronomy and Crop Science ,Food Science - Abstract
HighlightsThermal conductivity significantly decreased (p < 0.05), particularly in the last two weeks of the growing season.Thermal conductivity values were significantly different (p < 0.05) between the measurement locations.Thermal conductivity had a moderate correlation (0.35 < |r| < 0.67) with maturity indices.Abstract. ±±W m·K-1±±2-1 Keywords: Apple maturity, DNHP, Harvest time, Malus × domestica (Borkh.), Thermal conductivity, Thermal properties.
- Published
- 2020
- Full Text
- View/download PDF
20. The preclinical efficacy of the novel hypomethylating agent NTX-301 as a monotherapy and in combination with venetoclax in acute myeloid leukemia
- Author
-
Byungho Lim, Dabin Yoo, Younghwa Chun, Areum Go, Kyung-Jin Cho, Daeun Choi, Myoung Eun Jung, Ha Young Lee, Rebecca J. Boohaker, Jin Soo Lee, DooYoung Jung, and Gildon Choi
- Subjects
Leukemia, Myeloid, Acute ,Sulfonamides ,Oncology ,Antineoplastic Combined Chemotherapy Protocols ,Humans ,Hematology ,Bridged Bicyclo Compounds, Heterocyclic - Published
- 2022
21. LoRaWAN based internet of things (IoT) system for precision irrigation in plasticulture fresh-market tomato
- Author
-
Haozhe Zhang, Long He, Francesco Di Gioia, Daeun Choi, Antonio Elia, and Paul Heinemann
- Published
- 2022
- Full Text
- View/download PDF
22. Life history traits and reproductive ecology of North American chorus frogs of the genus Pseudacris (Hylidae)
- Author
-
Vance L. Trudeau, Jeffrey P. Ethier, Marc J. Mazerolle, Aurore Fayard, Daeun Choi, and Peter Soroye
- Subjects
Chorus frog ,Extinction ,biology ,Ecology ,Applied ecology ,Biodiversity ,Review ,Conservation ,Distribution ,biology.organism_classification ,Life history theory ,Hylidae ,Chorus frogs ,QL1-991 ,Population management ,Threatened species ,Conservation status ,Animal Science and Zoology ,Life history ,Zoology ,Ecology, Evolution, Behavior and Systematics - Abstract
Amphibian biodiversity is declining globally, with over 40% of species being considered threatened to become extinct. Crucial to the success of conservation initiatives are a comprehensive understanding of life history and reproductive ecology of target species. Here we provide an overview of the Pseudacris genus, including breeding behaviour, reproduction, development, survival and longevity. We present an updated distribution map of the 18 species found throughout North America. We also summarize the conservation status at the national and subnational (state, provincial, and territorial) levels, in Canada, USA, and Mexico, to evaluate the relationship between life history traits and extinction risk. Results show a high degree of consistency in the life history traits of Pseudacris species considering their relative diversity and wide distribution in North America. However, data are lacking for several species, particularly in the Fat Frog and West Coast clades, causing some uncertainties and discrepancies in the literature. We also found that the most threatened populations of chorus frog were located in the east coast of the USA, potentially as a result of increased levels of anthropogenic disturbance. We suggest that the similarities in life history traits among chorus frog species provides an opportunity for collaboration and united efforts for the conservation of the genus. Supplementary Information The online version contains supplementary material available at 10.1186/s12983-021-00425-w.
- Published
- 2021
- Full Text
- View/download PDF
23. In-Field Apple Size and Location Tracking Using Machine Vision to Assist Fruit Thinning and Harvest Decision-Making
- Author
-
Omeed Mirbod, James R. Schupp, Paul Heinz Heinemann, Long He, and Daeun Choi
- Subjects
Matching (statistics) ,Horticulture ,Thinning ,Machine vision ,Growing season ,Calipers ,Precision agriculture ,Orchard ,Pose ,Mathematics - Abstract
Monitoring of fruit size development has important implications for apple orchard management decision making such as scheduling for fruitlet chemical thinning and allocating resources for harvest. The current method for tracking fruit size development is by tagging a sample of fruits and using calipers or sizing rings to make measurements, which can be labor-intensive and time-consuming. In this study, a stereo vision system was developed which sized fruits on a tree and kept track of their growth during the season by matching fruit in images across time. Neural network models including Faster R-CNN and Mask R-CNN were used for fruit detection and on-tree fruit sizing. Camera pose estimation using feature matching of apples was used for tracking individual fruit growth. The best performance on fruit matching for the ‘Golden Delicious‘ variety during the growing season in an apple orchard was observed in September and October; 74% of all detected fruits which were fully visible were matched between the two months. Fruitlets averaging 25 mm in diameter also had a matching accuracy of 73% during two imaging trials performed on the same day for the month of June.
- Published
- 2021
- Full Text
- View/download PDF
24. Internet of Things (IoT)-Based Precision Irrigation With LoRaWAN Technology Applied to Vegetable Production
- Author
-
Long He, Daeun Choi, Paul Heinz Heinemann, Haozhe Zhang, and Francesco Di Gioia
- Subjects
Irrigation ,Precision irrigation ,Power consumption ,business.industry ,Yield (wine) ,Irrigation scheduling ,Production (economics) ,Agricultural engineering ,Internet of Things ,business ,Water content ,Mathematics - Abstract
Precision irrigation with sensors has proven to be effective for water saving in crop production. Internet of things (IoT) system is necessary for monitoring real-time data from sensors and automating irrigation systems. Long-range wide-area network (LoRaWAN) is low-cost and easy to be implemented in IoT systems that can be used for precision crop irrigation. In this study, an IoT-based precision irrigation system with LoRaWAN technology was developed and evaluated as a precision management tool on fresh-market tomato production in an open field. Four irrigation scheduling treatments were designed and tested, including ET (ETc), MP60 (Watermark 200SS-5 soil matric potential sensors, -60 kPa), MP40 (-40 kPa), and GesCoN (decision support system). The treatments were arranged based on a randomized complete block design (RCBD) with four replications. System feasibility, yield, and irrigation water use efficiency (iWUE) were evaluated during the experiment. The results indicated that treatment MP60 and GesCoN had a marketable yield 15.2% and 22.1% higher than ET, respectively. MP40 had a marketable yield 12.5% lower than ET. GesCoN had a significantly higher yield than ET and MP40. However, MP60 did not produce significantly different results from GesCoN and ET but had higher yield than MP40. MP40 received relatively low water via irrigation because of unproper installation and positioning of the soil moisture sensors, which caused a higher incidence of blossom end-rot and thus lower marketable yield. Nevertheless, the LoRaWAN-based IoT system worked well in terms of power consumption, communication, sensors reading and valve control. It can be potentially implemented for precision and automatic irrigation operation in vegetable fields.
- Published
- 2021
- Full Text
- View/download PDF
25. GNSS-IMU-assisted colored ICP for UAV-LiDAR point cloud registration of peach trees
- Author
-
Wenan Yuan, Daeun Choi, and Dimitrios Bolkas
- Subjects
Forestry ,Horticulture ,Agronomy and Crop Science ,Computer Science Applications - Published
- 2022
- Full Text
- View/download PDF
26. Critical enzymes for biosynthesis of cucurbitacin derivatives in watermelon and their biological significance
- Author
-
Yeong-Geun Lee, Ahra Cha, Daeun Choi, Youngseok Lee, Suman Rimal, Nam-In Baek, Young-Cheon Kim, Jiun Sang, and Sanghyeob Lee
- Subjects
0106 biological sciences ,0301 basic medicine ,Proton Magnetic Resonance Spectroscopy ,Plant physiology ,Medicine (miscellaneous) ,01 natural sciences ,Article ,General Biochemistry, Genetics and Molecular Biology ,Citrullus ,03 medical and health sciences ,chemistry.chemical_compound ,Cucurbitacins ,Biosynthesis ,Acetyltransferases ,Carbon-13 Magnetic Resonance Spectroscopy ,Secondary metabolism ,lcsh:QH301-705.5 ,chemistry.chemical_classification ,Chemistry ,Cucurbitacin ,Acetylation ,Carbon ,In vitro ,Biosynthetic Pathways ,Kinetics ,030104 developmental biology ,Enzyme ,lcsh:Biology (General) ,Biochemistry ,Biocatalysis ,General Agricultural and Biological Sciences ,010606 plant biology & botany - Abstract
Various cucurbitacins have been isolated, and their structures have been elucidated. Owing to their economic potential and importance as active pharmacological compounds, their cytotoxicity in various cancer cells has been assessed. Here, we mined several candidate genes with potential involvement in cucurbitacin biosynthesis in watermelon (Citrullus lanatus) and performed in vitro enzymatic assays and instrumental analyses using various substrates to identify cucurbitacin functions and products. Enzymatic activities of two acetyltransferases (ACTs) and one UDP-glucosyltransferase (UGT) against cucurbitacins were confirmed, resulting in the synthesis of novel cucurbitacins in vivo and/or in vitro to our knowledge. As ACTs and UGT are involved in the dynamic conversion of cucurbitacins by catalyzing acetylation and glucosylation at moieties in the cucurbitacins skeleton, these findings improve our knowledge on how these genes contribute to the diversity of cucurbitacins., Kim et al. use RNAseq of two watermelons to select candidate genes coding for enzymes that catalyze modifications of cucurbitacins. They characterise four of the 16 candidate enzymes (3 different acetyltransferases and one UDP-glucosyltransferase) by HPLC, LC-MS, NMR, and in vitro enzymatic assay. They further show with in vivo assay in Drosophila, that acetylation of cucurbitacin increases neuronal activity in insects.
- Published
- 2020
- Full Text
- View/download PDF
27. Internet of Things (IoT)-based Precision Irrigation with LoRaWAN Technology Applied to High Tunnel Vegetable Production
- Author
-
Haozhe Zhang, Paul Heinz Heinemann, Francesco Di Gioia, Long He, and Daeun Choi
- Subjects
Precision irrigation ,Computer science ,business.industry ,Production (economics) ,Agricultural engineering ,Internet of Things ,business - Published
- 2020
- Full Text
- View/download PDF
28. Immunopathogenesis of ANCA-Associated Vasculitis
- Author
-
Yunryoung Cho, Minha Hwang, Junhye Park, Hyo Jeong Lee, Kang Hyun Kim, Lee Smith, Ji Han Lee, Jae Il Shin, Han Li, Sun Wook Jung, Junseong Park, Hyungjun Kim, Do Young Kim, Andreas Kronbichler, Haejune Sung, Sara Denicolò, Hojune Lee, Geonjae Cho, Dong-Il Kim, Daeun Choi, Philipp Gauckler, Keum Hwa Lee, Dongkyu Lee, Hyung Tae Kim, Jaehyuk Hwang, Ai Koyanagi, Injae Hwang, Sohee Kim, Changjun Lee, Min Je Choi, Louis Jacob, Kalthoum Tizaoui, Donghyun Ahn, Innsbruck Medical University [Austria] (IMU), Yonsei University, Faculté de médecine - Faculty of Medicine [Sfax, Tunisie] (FMS), Université de Sfax - University of Sfax, University of Florida [Gainesville] (UF), Anglia Ruskin University (ARU), Centro de Investigación Biomédica en Red Salud Mental [Madrid] (CIBER-SAM), ICREA Infection Biology Laboratory (Department of Experimental and Health Sciences), Universitat Pompeu Fabra [Barcelona] (UPF), Université de Versailles Saint-Quentin-en-Yvelines - UFR Sciences de la santé Simone Veil (UVSQ Santé), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)
- Subjects
0301 basic medicine ,[SDV]Life Sciences [q-bio] ,Microscopic Polyangiitis ,Review ,Churg-Strauss Syndrome ,urologic and male genital diseases ,lcsh:Chemistry ,0302 clinical medicine ,Proteinase 3 ,immune system diseases ,Eosinophilic ,skin and connective tissue diseases ,lcsh:QH301-705.5 ,Spectroscopy ,biology ,treatment ,ANCA ,pathogenesis ,General Medicine ,Prognosis ,3. Good health ,Computer Science Applications ,Myeloperoxidase ,Biomarker (medicine) ,biomarker ,Microscopic polyangiitis ,Granulomatosis with polyangiitis ,Vasculitis ,phenotype ,Myeloblastin ,Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis ,Serogroup ,Catalysis ,Antibodies, Antineutrophil Cytoplasmic ,Inorganic Chemistry ,03 medical and health sciences ,medicine ,Humans ,cardiovascular diseases ,Physical and Theoretical Chemistry ,Molecular Biology ,Peroxidase ,030203 arthritis & rheumatology ,business.industry ,Organic Chemistry ,Granulomatosis with Polyangiitis ,medicine.disease ,respiratory tract diseases ,030104 developmental biology ,lcsh:Biology (General) ,lcsh:QD1-999 ,Immunology ,biology.protein ,Personalized medicine ,business ,Biomarkers - Abstract
International audience; Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is an autoimmune disorder which affects small-and, to a lesser degree, medium-sized vessels. ANCA-associated vasculitis encompasses three disease phenotypes: granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). This classification is largely based on clinical presentations and has several limitations. Recent research provided evidence that genetic background, risk of relapse, prognosis, and co-morbidities are more closely related to the ANCA serotype, proteinase 3 (PR3)-ANCA and myeloperoxidase (MPO)-ANCA, compared to the disease phenotypes GPA or MPA. This finding has been extended to the investigation of biomarkers predicting disease activity, which again more closely relate to the ANCA serotype. Discoveries related to the immunopathogenesis translated into clinical practice as targeted therapies are on the rise. This review will summarize the current understanding of the immunopathogenesis of ANCA-associated vasculitis and the interplay between ANCA serotype and proposed disease biomarkers and illustrate how the extending knowledge of the immunopathogenesis will likely translate into development of a personalized medicine approach in the management of ANCA-associated vasculitis.
- Published
- 2020
- Full Text
- View/download PDF
29. Hand-picking Dynamic Analysis for Robotic Agaricus Mushroom Harvesting
- Author
-
Long He, Daeun Choi, John Pecchia, Mingsen Huang, and Xiaohu Jiang
- Subjects
Mushroom ,Simplified methods ,Bending (metalworking) ,biology ,Computer science ,Index finger ,biology.organism_classification ,Force sensor ,Contact force ,medicine.anatomical_structure ,Inertial measurement unit ,Agaricus ,medicine ,Simulation - Abstract
Mushrooms are picked manually one by one, which is time consuming and labor intensive. Robotic harvesting is an alternative method to address this issue. The purpose of this paper was to assess hand-picking methods as candidate techniques for implementation in a robotic end-effector designed to harvest Agaricus mushrooms. Conventional manual mushroom picking comprises a combination motion of twisting, bending, and lifting. To find an effective and simple picking method for robotic harvesting, a series of picking force and motion studies were conducted to compare among different picking methods. Four picking motions were considered, including conventional method, and three simplified methods, namely, bending, lifting, and twisting. The sensors used during picking included three force sensors and an inertial measurement unit. A damage test on the mushroom cap was also conducted to analyze the crop bruise level under different forces and acting duration. Experimental data were recorded for normal contact forces and mushroom rotation angles. The conventional picking method required the most orientation changes to detach a mushroom, which could generate complexity for designing a robotic end-effector with the equivalent dexterity. The test results indicated that bending was a simple and effective method for mushroom separation due to the least picking time and force needed compared to the other three patterns. Both lifting and twisting methods required a larger force on the index finger than on the thumb to detach mushrooms, which resulted in lower success pick rate and obvious bruise damage. The results also indicated that a bigger contacting force was the major reason for causing bruising, by comparing with the acting time. The outcomes could provide some guideline information for developing a robotic mushroom picking system for Agaricus mushroom harvesting.
- Published
- 2020
- Full Text
- View/download PDF
30. Collision free Path Planning of a Robotic Manipulator for Pruning Apple Trees
- Author
-
Daeun Choi, Long He, Paul Heinz Heinemann, Azlan Zahid, and James R. Schupp
- Subjects
Computer Science::Robotics ,Path length ,Control theory ,Computer science ,Obstacle ,Random tree ,Path (graph theory) ,Motion planning ,Pruning (decision trees) ,Degrees of freedom (mechanics) ,Smoothing - Abstract
Pruning of apple trees requires 80-120 working hours of labor per hectare accounting for 20% of the total production cost. Robotic pruning is a potential solution to decrease labor dependence and associated costs. Autonomous precise manipulation of a robotic manipulator in presence of obstacles is a challenge. The spatial requirements and collision-free path planning for the robotic manipulator is essential for automated systems. This simulation study focused on investigating the branch accessibility of a six-rotational (6R) degrees of freedom (DoF) robotic manipulator with a shear blade type end-effector. A virtual tree canopy environment was established in MATLAB for simulation. The Rapidly-exploring Random Tree (RRT) obstacle avoidance algorithm was used to establish a collision-free path to reach the target pruning points. The path smoothing and optimization algorithms were also used to reduce path length and calculate the optimize path. The simulation showed that the integrated robotic manipulator reached the pruning points avoiding obstacle untargeted branches. The path generation time, path length, target reaching time, and number of accessible branches (success) and collisions (failure) was recorded. The study provides the foundation information for future work on the development of a robotic pruning system
- Published
- 2020
- Full Text
- View/download PDF
31. Towards Image-Based Measurement of Accurate Apple Size and Yield Using Stereo Vision Cameras
- Author
-
Daeun Choi, Paul Heinz Heinemann, Richard P Marini, and Omeed Mirbod
- Subjects
Stereopsis ,business.industry ,Orientation (computer vision) ,Computer science ,3D reconstruction ,Metric (mathematics) ,Computer vision ,Precision agriculture ,Image segmentation ,Artificial intelligence ,Orchard ,business ,Convolutional neural network - Abstract
Accurate measurement of fruit size in apple orchards before harvest can have important implications on profits and management practices. Obtaining a distribution of fruit size can be labor intensive for a large orchard and therefore requires an automated system that can quickly and accurately size fruit on every tree. This study proposes an automated imaging system that uses stereo vision for finding the metric surface area of apples. Deep convolutional neural network models were utilized to classify apples as ideal candidates for sizing based on their orientation and visibility in an image. The results produced a correlation of apple size to apple weight of R2=0.69 making the system capable of capturing variability in fruit diameter distribution that ranges by 1cm (or equivalently 60 grams). There was also an improvement in correlation to yield when combining fruit size with fruit count than when utilizing fruit count alone.
- Published
- 2020
- Full Text
- View/download PDF
32. Japan's Foreign Policy on Postwar Issues Relating to South Korea
- Author
-
Daeun Choi and Ja Hyun Chun
- Subjects
Sociology and Political Science ,Foreign policy ,Political science ,Political economy ,05 social sciences ,Political Science and International Relations ,050602 political science & public administration ,050601 international relations ,0506 political science - Published
- 2018
- Full Text
- View/download PDF
33. Comparative Study about Motive for Blood Donation, Knowledge and Attitude by University Student’s Experiences of Blood Donation
- Author
-
Nayoung Kim, So Yeon Kim, Daeun Choi, Na-Yeon Shin, Min-Kyo Choi, Ae-Lim Heo, Kyungeui Bae, Su-Min Park, and Su-Bin Lee
- Subjects
Medical education ,Blood donor ,General Medicine ,Psychology - Published
- 2018
- Full Text
- View/download PDF
34. Profiling cucurbitacins from diverse watermelons (Citrullus spp.)
- Author
-
Hai-feng Liu, Young-Cheon Kim, Sanghyeob Lee, Chunying Zhang, and Daeun Choi
- Subjects
0106 biological sciences ,0301 basic medicine ,chemistry.chemical_classification ,Citrullus lanatus ,biology ,Traditional medicine ,Cucurbitacin ,Glycoside ,Plant Science ,Horticulture ,biology.organism_classification ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,Cucurbitacins ,chemistry ,Citrullus colocynthis ,Citrullus ,Cucurbitaceae ,010606 plant biology & botany ,Biotechnology ,Cucurbitacin E - Abstract
Cucurbitacins are a group of tetracyclic triterpenes produced by members of the Cucurbitaceae family that are known for their bitter taste, and have both positive and negative attributes based on their use. The aim of the present study was to profile cucurbitacins through the quantitative analysis of diverse watermelon (Citrullus spp.) germplasms, including Citrullus colocynthis and Citrullus lanatus, using liquid chromatography–mass spectrometry (LC–MS) and high performance liquid chromatography. We isolated cucurbitacins B and E, and cucurbitacin E glycoside and evaluated the concentration of these compounds in watermelon leaves, fruits, and seedling extracts. High amounts of cucurbitacin E glycosides were found in most of the C. colocynthis leaves at concentrations between 1.3 and 0.9 mg/g of fresh weight, while relatively low concentrations of cucurbitacin B and E were detectable in these tissues. Interestingly, cucurbitacin E glycosides were only detected in most C. colocynthis fruits at concentrations between 0.21 and 3.2 mg/g fresh weight. We also confirmed the correlation between bitter taste and cucurbitacin E glycoside content. Cucurbitacin B and E and cucurbitacin E glycoside were found in most of the cultivars tested, while cucurbitacin agylcones were the primary cucurbitacins identified in seedlings. This study reveals the cucurbitacin composition in various watermelon germplasms and in different plant tissue.
- Published
- 2018
- Full Text
- View/download PDF
35. Detection and counting of immature green citrus fruit based on the Local Binary Patterns (LBP) feature using illumination-normalized images
- Author
-
Won Suk Lee, Justice Diamond, Xiangjun Zou, Daeun Choi, Hao Gan, and Chenglin Wang
- Subjects
business.industry ,Local binary patterns ,010401 analytical chemistry ,Mistake ,Pattern recognition ,04 agricultural and veterinary sciences ,01 natural sciences ,0104 chemical sciences ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Artificial intelligence ,General Agricultural and Biological Sciences ,business ,Citrus fruit ,Mathematics - Abstract
The original version of this article unfortunately contained a mistake. The affiliation “China West Normal University” should be removed from the author Dr. Chenglin Wang. The correct affiliation details are given below.
- Published
- 2018
- Full Text
- View/download PDF
36. RNA expression, protein activity, and interactions in the ACC synthase gene family in cucumber (Cucumis sativus L.)
- Author
-
Ji Hoon Han, Sanghyeob Lee, Jeong Hwan Lee, Youjin Jung, Young-Cheon Kim, and Daeun Choi
- Subjects
0106 biological sciences ,0301 basic medicine ,chemistry.chemical_classification ,Gene isoform ,ATP synthase ,biology ,Plant Science ,Horticulture ,biology.organism_classification ,01 natural sciences ,Amino acid ,Gene expression profiling ,03 medical and health sciences ,030104 developmental biology ,chemistry ,Biochemistry ,Arabidopsis ,biology.protein ,Gene family ,Gene ,Cucumis ,010606 plant biology & botany ,Biotechnology - Abstract
Ethylene is an important regulator of developmental and stress responses in plants, and 1-aminocyclopropane-1-carboxylic acid synthase (ACS) proteins catalyze one of the rate-limiting steps in endogenous ethylene biosynthesis. Accordingly, the function of ACS family genes has been extensively studied in plants including Arabidopsis and tomato; however, little is known about the systemic function of ACS genes in cucumber (Cucumis sativus L.). Here, we investigated the expression patterns of eight cucumber ACS family genes (CsACSs) in a variety of tissues and sex types, as well as in response to exogenous ethylene application, and their ACS activities. Tissue-specific expression profiling in monoecious and gynoecious cucumber plants revealed that some CsACSs were differentially expressed. In particular, the five genes CsACS1, CsACS1-2, CsACS2, CsACS6, and CsACS11 were highly expressed in the shoot apex regions of gynoecious and hermaphroditic cucumber plants. The expression of most CsACSs was also induced by exogenous ethylene application. Furthermore, three CsACS isoforms (CsACS9, CsACS10, and CsACS12) showed no ACS enzymatic activity, which was associated with the amino acid variations in the conserved active residues of CsACS proteins. However, an in vitro pull-down assay revealed that two enzymatically inactive isoforms (CsACS9 and CsACS10) did not significantly interact with four active isoforms (CsACS1, CsACS1-2, CsACS2, and CsACS6). Taken together, our findings will be valuable for elucidating the relationship between RNA expression, ACS activity, protein–protein interactions between CsACSs and cucumber sex types.
- Published
- 2018
- Full Text
- View/download PDF
37. LiDAR-sensed tree canopy correction in uneven terrain conditions using a sensor fusion approach for precision sprayers
- Author
-
Grzegorz Krawczyk, Azlan Zahid, Long He, Daeun Choi, Sultan Mahmud, and Heping Zhu
- Subjects
Canopy ,Tree canopy ,Forestry ,Ranging ,Terrain ,Horticulture ,Sensor fusion ,Computer Science Applications ,Tree (data structure) ,Lidar ,Environmental science ,Agronomy and Crop Science ,Inertial navigation system ,Remote sensing - Abstract
Precision spraying is one of the most promising techniques to produce healthy and sustainably profitable crops. However, accurate canopy density measurements for precision spraying decisions are still a challenging endeavor, especially in orchards with uneven terrain conditions. A sensor fusion-based canopy point correction system was developed with a 3D light detection and ranging (LiDAR) sensor and an inertial navigation system-global navigation satellite system (INS-GNSS) for accurate tree canopy density measurement. The LiDAR sensor was used to acquire the tree canopy architectures, while the INS-GNSS sensor was to evaluate the terrain slopes and the tree georeferenced locations. A mathematical model was developed to perform the simulation for correction of canopy points based on given changes in the roll, pitch, and yaw angles. A sensor fusion algorithm was developed to process the canopy point corrections for the tree fruit orchards with three different sloping conditions, including longitudinal, lateral, and combination of both slopes. Simulation results reported that the developed model established the correction of tree canopy points with varying roll, pitch, and yaw angles. Field evaluation results suggested that the developed system could be used for correcting canopy points at any sloping conditions in various terrains. The measured tree canopy density from the corrected canopy points reported a possible of off-target chemical reduction up to 13.87%, 5.19%, and 15.45% in orchard sites 1, 2 and 3, respectively. With the accurate tree canopy density measurement, it is anticipated that the developed system could be used to reduce the off-target deposition for precision spraying applications in uneven tree fruit orchards.
- Published
- 2021
- Full Text
- View/download PDF
38. A Study on Preclinical Efficacy, Underlying Mechanisms, and Sensitivity Markers of a Novel Hypomethylating Agent Ntx-301 in Acute Myeloid Leukemia
- Author
-
Myoung Eun Jung, Gildon Choi, Dabin Yoo, Younghwa Chun, Byungho Lim, Jin Soo Lee, Areum Go, Doo Young Jung, Kyung-jin Cho, Daeun Choi, and Ha Young Lee
- Subjects
Hypomethylating agent ,business.industry ,Immunology ,Cancer research ,Medicine ,Myeloid leukemia ,Cell Biology ,Hematology ,Sensitivity (control systems) ,business ,Biochemistry - Abstract
Introduction: While intensive induction chemotherapy has been standard-or-care for patients with acute myeloid leukemia (AML), intensive regimens have often been limited in elderly patients with comorbidities. As an alternative option, less intensive hypomethylating agents (HMAs), decitabine (DAC) and azacitidine (AZA), are currently being used in these unfit patients. However, their low response rates and adverse events when administered alone suggest a need to develop novel HMAs that elicit enhanced efficacy and reduced mortality. A recent study demonstrated pharmacological improvements of a novel 4′-thio-modified analog, 5-aza-4′-thio-2′-deoxycytidine (hereafter NTX-301), including enhanced chemical stability and incorporation into DNA and improved preclinical efficacy (Thottassery, 2014). However, the mechanism of action (MoA) of NTX-301 has not yet been understood. Herein, we aim to thoroughly investigate the preclinical efficacy and MoAs of NTX-301 in AML through comparative analysis with DAC and AZA. To this end, we used in vitro and in vivo preclinical models of AML and performed multiomics-based analyses. Results: We comprehensively examined viability of 200 cancer cell lines (CCLs) upon treatment with NTX-301. Consistent with the current use of HMAs as therapeutics for hematologic malignancies, this sensitivity profiling displayed the most remarkable potency of NTX-301 toward blood CCLs (OR=3.97, p=0.0003). In addition, phenotypic assays revealed that the anti-leukemic activity of NTX-301 was superior to that of DAC, which is attributed to more effective actions in inducing apoptosis, cell cycle arrest, and differentiation. Supporting the in vitro results, orally administrated NTX-301 led to more potent tumor regression, better tolerability, and survival benefits over DAC and AZA in both systemic (1.5-2.0 mg/kg, qdx5 then 2 days off, 5 days on, and 9 days off, for 3 cycles) and subcutaneous (0.2-1.5 mg/kg) xenograft models. To assess the underlying MoAs, we interrogated global alterations at the transcriptome and methylome levels upon treatment with NTX-301 in three AML cell lines using RNA sequencing and methylation array. Methylome analyses revealed that NTX-301-induced demethylation patterns were distinguished from DAC; DAC triggered stronger global demethylation than NTX-301 did, whereas NTX-301 derived rather selective demethylation, preferentially in early-replicating regions, H3K27ac-marked regions, and non-CpG islands. In transcriptome analyses compared with DAC, NTX-301 more markedly elicited a transcriptional reversal toward a normal myeloid-like signature by increasing a differentiation signature and suppressing a leukemic stem cell signature. NTX-301 also mediated more pronounced activation of DNA damage response and the p53 pathway, which are characterized by marked induction of pH2AX and pChk1 and increased stability of p53, respectively. Given the synthetic lethality of p53 activation and BCL2 inhibition (Rongqing, 2017), stronger p53 stabilization by NTX-301 may confer more benefits in combination with venetoclax. Indeed, the combination of NTX-301 + venetoclax produced a more synergistic combination index compared with DAC + venetoclax. Strikingly, the combined NTX-301 (0.5-2.0 mg/kg) + venetoclax (50 mg/kg) achieved complete tumor remission, no notable toxicity, and prolonged survival benefits over AZA (2.5 mg/kg) + venetoclax (50 mg/kg) in preclinical models of AML. By integrating sensitivity profiles and multiomics data of 200 CCLs, we interrogated molecular determinants associated with sensitivity to NTX-301. Intriguingly, when comparing methylomes between sensitive and resistant CCLs, we found a significantly biased global hypermethylation trend toward sensitive CCLs. A combinatorial set of the most significantly biased 352 differentially methylated regions (FDR Conclusions: Our study demonstrated an improved therapeutic index of NTX-301 over traditional HMAs, providing a rationale for further clinical development of the agent as a single-agent or in combination with other agents. We also believe that our study for MoAs and biomarkers will improve our understanding of NTX-301. Disclosures Lim: Pinotbio: Research Funding. Yoo: Pinotbio: Research Funding. Cho: Pinotbio: Research Funding. Choi: Pinotbio: Research Funding. Jung: Pinotbio: Research Funding. Jung: Pinotbio: Current Employment. Lee: Pinotbio: Current Employment. Chun: Pinotbio: Current Employment. Go: Pinotbio: Current Employment. Lee: Pinotbio: Current Employment. Choi: Pinotbio: Research Funding.
- Published
- 2021
- Full Text
- View/download PDF
39. Technological advancements towards developing a robotic pruner for apple trees: A review
- Author
-
Long He, Azlan Zahid, Daeun Choi, Sultan Mahmud, James R. Schupp, and Paul Heinz Heinemann
- Subjects
business.industry ,Technological change ,Computer science ,Machine vision ,Forestry ,Economic shortage ,Robotics ,Horticulture ,Automation ,Manufacturing engineering ,Computer Science Applications ,Obstacle avoidance ,Artificial intelligence ,Motion planning ,business ,Agronomy and Crop Science ,Pruning - Abstract
Automation and robotics have been widely applied in many agricultural operations; however, the production operations of apple trees are usually performed manually. Pruning is one of the most labor-intensive operations, accounting for about 20% of the total labor costs. Robotic pruning is a potential long-term solution to deal with the issue of labor shortages and associated high costs. In recent years, researchers have advanced technologies that could lead to the development of a robotic pruning system. However, numerous challenges are involved for successful adoption of robotic pruning technologies. This review highlighted the technological progress in the core components of a robotic pruner including machine vision, manipulator, end-effector, path planning, and obstacle avoidance; the challenges associated with the existing technologies; and potential solutions to the development of an automated pruning system. The review covers both scientific/research and commercial technologies developed for robotic tree pruning. The available literature related to all technological components of a robotic pruning system was reviewed in detail, and useful information was synthesized for presenting in the paper. Finally, the paper scrutinizes the challenges and potential future opportunities for developing a robotic pruning system for a sustainable apple production system.
- Published
- 2021
- Full Text
- View/download PDF
40. Overcurrent-driven LEDs for consistent image colour and brightness in agricultural machine vision applications
- Author
-
Daeun Choi, Roderick S. Thomas, Omeed Mirbod, and Long He
- Subjects
Brightness ,Computer science ,business.industry ,Machine vision ,Motion blur ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Illuminance ,Forestry ,Horticulture ,Computer Science Applications ,Overcurrent ,law.invention ,Flash (photography) ,Stereopsis ,law ,Computer vision ,Artificial intelligence ,business ,Agronomy and Crop Science ,Light-emitting diode - Abstract
Machine vision systems are being utilized extensively in agriculture applications. Daytime imaging in outdoor field conditions presents challenges such as variable lighting and colour inconsistencies due to sunlight. Motion blur can occur due to vehicle movement and vibrations from ground terrain. A camera system with active lighting can be a solution to overcome these challenges. In this study, the usage of over-current driven LEDs to produce a powerful flash was investigated as a viable light source for daytime imaging. The current drawn by an LED was increased by a factor of six times its normal rating resulting in increased illuminance. A circuit was designed for storing and releasing energy to the LEDs for a strobe-like effect and a controller was used for synchronizing the strobe with a camera to acquire images. The system was deployed in an apple orchard on three days in summer of 2020. Images were taken throughout the day in both sunny and cloudy conditions of different canopy structures. There was substantial improvement in image brightness and colour consistency by using the LED flashes. Images captured by the prototype system during an 11-hour period showed an average decrease of 85% in standard deviation for the Hue-Saturation-Value (HSV) channels compared to that of the auto-exposure setting. Additionally, the prototype system was able to fix motion blur in images averaging 7 mm in error for a stereo vision application with the camera moving at 7 km/hr. These results show that the designed LED flash system can reduce the undesirable effects of lighting variability and motion blur in images stemming from outdoor field conditions.
- Published
- 2021
- Full Text
- View/download PDF
41. RootRobot: A Field-based Platform for Maize Root System Architecture Phenotyping
- Author
-
Xiaomeng Shi, Paul Heinz Heinemann, Daeun Choi, Jonathan Lynch, and Molly Hanlon
- Subjects
Computer architecture ,Computer science ,Root system architecture ,Field based - Published
- 2019
- Full Text
- View/download PDF
42. Tree Trunk Position Estimation for Accurate Fruit Counts in Apple Yield Mapping
- Author
-
Daeun Choi, Paul Heinz Heinemann, Thomas Dh Jarvinen, Tara Auxt Baugher, and James R. Schupp
- Subjects
Estimation ,Position (vector) ,Statistics ,Tree trunk ,Yield mapping ,Mathematics - Published
- 2019
- Full Text
- View/download PDF
43. Development of A Mushroom Harvesting Assistance System using Computer Vision
- Author
-
John Pecchia, Paul Heinz Heinemann, Long He, Daeun Choi, and Cheng Hao Lee
- Subjects
Engineering management ,Mushroom ,Engineering ,business.industry ,business - Published
- 2019
- Full Text
- View/download PDF
44. Investigation of Sensor-Based Irrigation Systems for Apple Orchards
- Author
-
Long He, Daeun Choi, and Lihua Zeng
- Subjects
Irrigation ,Environmental science ,Agricultural engineering - Published
- 2019
- Full Text
- View/download PDF
45. Picking dynamic analysis for robotic harvesting of Agaricus bisporus mushrooms
- Author
-
Daeun Choi, Yaoming Li, Long He, John Pecchia, and Mingsen Huang
- Subjects
0106 biological sciences ,Sensor system ,Alternative methods ,Simplified methods ,Bending (metalworking) ,business.industry ,Computer science ,Orientation (computer vision) ,Forestry ,04 agricultural and veterinary sciences ,Horticulture ,01 natural sciences ,Force sensor ,Computer Science Applications ,Inertial measurement unit ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Computer vision ,Artificial intelligence ,business ,Agronomy and Crop Science ,Agaricus bisporus ,010606 plant biology & botany - Abstract
Button mushrooms (Agaricus bisporus) are picked by hand individually, which is time consuming and labor intensive. Robotic harvesting is an alternative method to address this issue. Picking force and motion are critical for developing an effective robotic mushroom picking end-effector. Mushrooms are typically growing in a cluster. Conventional manual mushroom picking comprises a combination motion of twisting, bending, and lifting. To find an effective and simple picking method for robotic harvesting, a series of tests were conducted to compare the picking force and motion among the conventional method and three simplified methods, i.e., bending, twisting, and lifting. A sensor system was developed to measure the picking force and motion with three force sensors and an inertial measurement unit (IMU). The results showed that the conventional picking method required the most orientation changes to detach a mushroom, which could generate complexity for designing a robotic end-effector with the equivalent dexterity. The bending method was simple and effective with the least force compared to the other three methods, with the operation time, detachment angle, and peak force of 0.9 ± 0.5 s,13.6 ± 6.7°, and 3.3 ± 2.4 N respectively. A vacuum picking end-effector was then designed and evaluated with the three simplified methods. The results of picking end-effector evaluation also indicated that the bending motion achieved the best performance, with the picking rate of 100% for these target mushrooms, especially for the clustered ones. The developed picking end-effector can be further improved for an automatic mushroom picking system in the future.
- Published
- 2021
- Full Text
- View/download PDF
46. Development of a LiDAR-guided section-based tree canopy density measurement system for precision spray applications
- Author
-
Daeun Choi, Grzegorz Krawczyk, Long He, Azlan Zahid, Paul Heinz Heinemann, Sultan Mahmud, and Heping Zhu
- Subjects
0106 biological sciences ,Canopy ,Tree canopy ,Sprayer ,Point cloud ,Forestry ,Ranging ,04 agricultural and veterinary sciences ,Horticulture ,01 natural sciences ,Computer Science Applications ,Tree (data structure) ,Lidar ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Orchard ,Agronomy and Crop Science ,010606 plant biology & botany ,Remote sensing ,Mathematics - Abstract
An unmanned ground-based canopy density measurement system to support precision spraying in apple orchards was developed to precisely apply pesticides to orchard canopies. The automated measurement system was comprised of a light detection and ranging (LiDAR) sensor, an interface box for data transmission, and a laptop computer. A data processing and analysis algorithm was developed to measure point cloud indices from the LiDAR sensor to describe the distribution of tree canopy density within four sections according to the position of the trellis wires. Experiments were conducted in two orchard sites, one with GoldRush (larger trees) and the other one with Fuji (smaller trees) apple trees. Tree leaves were counted manually from each section separated by trellis wires. Field evaluation results showed a strong correlation of 0.95 (R2 = 89.30%) between point cloud data and number of leaves for the Fuji block and a correlation of 0.82 (R2 = 67.16%) was obtained for the GoldRush block. A strong correlation of 0.98 (R2 = 95.90%) was achieved in the relationship between canopy volume and number of leaves. Finally, a canopy density map was generated to provide a graphical view of the tree canopy density in different sections. Since accurate canopy density information was computed, it is anticipated that the developed prototype system can guide the sprayer unit for reducing excessive pesticide use in orchards.
- Published
- 2021
- Full Text
- View/download PDF
47. Dietary quality of lunches in senior leisure service facilities in South Korea: analysis of data from the 2013–2017 Korea National Health and Nutrition Examination Survey
- Author
-
Hae Ryun Park, Kyunghee Song, Daeun Choi, Jinah Hwang, and Youngmi Lee
- Subjects
senior leisure service facilities ,0301 basic medicine ,Service (business) ,Meal ,030109 nutrition & dietetics ,Nutrition and Dietetics ,National Health and Nutrition Examination Survey ,business.industry ,Significant difference ,Confounding ,030209 endocrinology & metabolism ,Food group ,03 medical and health sciences ,0302 clinical medicine ,Nutrient ,Diet quality ,nutrients ,Environmental health ,lunch ,Medicine ,business ,Original Research ,Aged ,Food Science - Abstract
BACKGROUND/OBJECTIVES This study analyzed the quality of lunches provided in senior leisure service (SLS) facilities and compared institutional foodservice (IF) and non-institutional foodservice (non-IF). SUBJECTS/METHODS Data of 390 adults aged 65 years or older who ate lunches in SLS facilities were analyzed using the information from the 2013–2017 Korea National Health and Nutrition Examination Survey. The participants were classified into IF (n = 129) and non-IF (n = 261) groups according to meal type provided. The intake of major food groups, energy and nutrients, and nutrient adequacy ratio (NAR) and mean adequacy ratio (MAR) were analyzed. The diversity of meals was evaluated by food group patterns, dietary diversity score (DDS) and dietary variety score (DVS). Energy intake was adjusted in model 1, while energy and sex were adjusted in model 2. All confounding variables were adjusted in model 3. RESULTS The intake of seafoods (P < 0.001 in models 1, 2, and 3), seaweeds (P < 0.01 in models 1 and 2), and dairy products (P < 0.05 in models 1, 2, and 3) was significantly higher in the IF group. No significant difference existed in energy intake; however, the intake of all nutrients except carbohydrate and vitamin C was significantly higher in the IF group. NAR of all nutrients, excluding vitamin C, was higher in the IF group, and MAR was also higher in the IF group (P < 0.001 in models 1, 2, and 3). The IF group had significantly higher DDS and DVS than the non-IF group (P < 0.001). CONCLUSIONS The lunches provided in SLS facilities were better in terms of quantity and quality when provided through IF than through non-IF. More systematic foodservice programs should be implemented in SLS facilities, especially in facilities wherein users prepare their own meals.
- Published
- 2021
- Full Text
- View/download PDF
48. The Effect of Sex on the Azoxymethane/Dextran Sulfate Sodium-treated Mice Model of Colon Cancer
- Author
-
Daeun Choi, Ha-Na Lee, Sung Hwa Sohn, Ryoung Hee Nam, Nayoung Kim, Jihee Sung, Sun Min Lee, Min Hee Ham, Hee Jin Son, Ji Hyun Park, Dong Ho Lee, Eun Shin, and Young-Jae Hwang
- Subjects
medicine.medical_specialty ,Colorectal cancer ,Colonic neoplasms ,medicine.medical_treatment ,Disease models ,medicine.disease_cause ,Gastroenterology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Medicine ,animal ,Colitis ,biology ,business.industry ,Azoxymethane ,Cancer ,Interleukin ,medicine.disease ,Cytokine ,chemistry ,030220 oncology & carcinogenesis ,Myeloperoxidase ,biology.protein ,030211 gastroenterology & hepatology ,Original Article ,Sex ,business ,Carcinogenesis - Abstract
BACKGROUND The colitis-associated cancer exhibits different characteristics according to sex in the initiation and progression of the tumors. The aim of this study was to investigate the sex-associated difference in the azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colitis-associated cancer model. METHODS The AOM/DSS ICR mouse model was established to compare male with female, and then the severity of colitis-associated carcinogenesis was examined macroscopically and histologically regarding the number, size, and location of tumors. Subsequently, levels of colonic mucosal cytokine, interleukin (IL)-1β and myeloperoxidase (MPO) were assessed. RESULTS At the 16th week, the tumor multiplicity and the pro-inflammatory factors differed according to sex. The total tumor number was significantly higher in male (P = 0.020) and the number of large tumors (diameter > 2 mm) was higher in male (P = 0.026). In male, the tumors located more in distal colon (P = 0.001). MPO was significantly higher in AOM/DSS-treated male mice compared to the control group (P = 0.003), whereas the corresponding female group showed no significant change (P = 0.086). Colonic IL-1β level significantly increased in AOM/DSS groups compared to control groups both in male and female (male, P = 0.014; female, P = 0.005). It was higher in male group; however, there was no statistical significance (P = 0.226). CONCLUSIONS In AOM/DSS murine model, colitis-associated colon tumorigenesis are induced more severely in male mice than female probably by way of inflammatory mediators such as IL-1β and MPO. The sex-related differences at the animal model of colon cancer suggest the importance of approach to disease with sex-specific medicine in human.
- Published
- 2016
49. Effect of N-Methyl-N-Nitrosourea onHelicobacter-induced Gastric Carcinogenesis in C57BL/6 Mice
- Author
-
Yoon Jin Choi, Ju Yup Lee, Daeun Choi, Dong Ho Lee, Seonmin Lee, Nayoung Kim, Yoon Jeong Choi, Jin Wook Kim, Hye Seung Lee, and Ryoung Hee Nam
- Subjects
medicine.medical_specialty ,biology ,business.industry ,Felis ,digestive, oral, and skin physiology ,Cancer ,Helicobacter pylori ,medicine.disease ,biology.organism_classification ,Gastroenterology ,03 medical and health sciences ,0302 clinical medicine ,030220 oncology & carcinogenesis ,Internal medicine ,Myeloperoxidase ,medicine ,biology.protein ,Helicobacter felis ,030211 gastroenterology & hepatology ,Histopathology ,Helicobacter ,business ,Gastric Neoplasm - Abstract
BACKGROUND The aim of this study was to investigate the effect of N-methyl-N-nitrosourea (MNU) treatment followed by chronic Helicobacter pylori SS1 and H. felis colonization on the stomachs of C57BL/6 mice. The role of MNU and Helicobacter species in gastric carcinogenesis was also elucidated. METHODS A total of 69 C57BL/6 mice at 4 weeks of age were divided into 6 groups according to MNU treatment and H. pylori SS1 or H. felis infection. The mice were sacrificed at 21 and 50 weeks. The degree of inflammation was determined by histopathology. The levels of gastric mucosal myeloperoxidase, TNF-α, and interleukin-1β (IL-1β) were measured by ELISA. RESULTS In the H. felis groups with or without MNU, the incidence of gastric tumors was 21.1% and 35.0% at 21 and 50 weeks, respectively. No gastric tumors were observed in all control mice. At 50 weeks, 37.5% of gastric adenoma cases were observed in the H. felis alone and MNU + H. felis groups. Furthermore, 12.5% of gastric adenocarcinoma cases were observed in the MNU alone and MNU + H. felis groups. The gastric mucosal IL-1β level was significantly higher in the MNU + H. felis group at 21 weeks and H. felis group at 50 weeks, respectively, than that for control mice (P < 0.05). However, the effect of MNU on H. pylori SS1-induced gastric carcinogenesis was low compared to that on H. felis. CONCLUSIONS Administration of MNU before H. felis infection provokes severe inflammation through IL-1β, and eventually induces gastric cancer. However, the role of MNU in H. pylori SS1-induced gastric carcinogenesis model is minor.
- Published
- 2016
- Full Text
- View/download PDF
50. Detection of dropped citrus fruit on the ground and evaluation of decay stages in varying illumination conditions
- Author
-
Reza Ehsani, John K. Schueller, Won Suk Lee, Fritz M. Roka, and Daeun Choi
- Subjects
Brightness ,business.industry ,Forestry ,04 agricultural and veterinary sciences ,02 engineering and technology ,Illumination problem ,Horticulture ,Standard deviation ,Computer Science Applications ,Hough transform ,law.invention ,law ,040103 agronomy & agriculture ,0202 electrical engineering, electronic engineering, information engineering ,False positive paradox ,Canny edge detector ,0401 agriculture, forestry, and fisheries ,020201 artificial intelligence & image processing ,Adaptive histogram equalization ,Computer vision ,Artificial intelligence ,business ,Agronomy and Crop Science ,Mathematics ,Citrus fruit - Abstract
An image brightness enhancement algorithm for outdoor images was proposed.Images had constant brightness after enhancement regardless of the original brightness.Applied canny edge density was proposed to choose the best citrus-containing circle.The detection algorithm showed different performances depending on size of sub-image.Highest performance was 89.6% for correct identification and 5.0% for false positive. The devastating disease Huanglongbing (HLB) has greatly affected citrus in Florida and other growing regions. Detecting dropped fruit is one method of estimating the presence and severity of the disease. The purpose of this study was to develop a machine vision system that can detect dropped citrus on the ground in varying illumination conditions and identify decaying stages of the dropped fruit. In this paper, a novel method for image brightness correction using a contrast limited adaptive histogram equalization was developed to produce constant image brightness levels between and within images. Objectives of this study were to: (1) solve the varying illumination problem and create a consistent brightness level between and within the images, (2) develop an algorithm to eliminate multiple detections of a single fruit from the circular Hough transform, (3) design an algorithm to evaluate decaying stages of the dropped citrus, and (4) demonstrate ability to create a fruit drop map of citrus at each decaying stage in a commercial citrus grove. The result shows all processed images had desired brightness levels (152 out of 255) with a standard deviation of 1.0. Correct identification of fruit and false positives were measured as 89.6% and 5.0%, respectively. False classifications of decay stages of fruit were as low as 4.2% and 18.5% for recently dropped fruit and rotten fruit, respectively. The techniques developed in this work could be further developed into a commercial machine vision system for a real-time dropped fruit mapping system.
- Published
- 2016
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.