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Predicting Concrete Compressive Strength Using Deep Convolutional Neural Network Based on Image Characteristics

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Computers, Materials & Continua 2020年第10期65卷 1-17页

作者： Sanghyo Lee Yonghan ahn Ha Young Kim Division of Architecture and Civil Engineering Kangwon National UniversitySamcheok-si25913Korea School of Architecture and Architectural Engineering Hanyang University ERICAAnsan-si15588Korea Graduate School of Information Yonsei UniversitySeoul03722Korea

In this study,we examined the efficacy of a deep convolutional neural network(DCNN)in recognizing concrete surface images and predicting the compressive strength of concrete.A digital single-lens reflex(DSLR)camera and microscope were simultaneously used to obtain concrete surface images used as the input data for the ***,training,validation,and testing of the DCNNs were performed based on the DSLR camera and microscope image *** of the analysis indicated that the DCNN employing DSLR image data achieved a relatively higher *** accuracy of the DSLR-derived image data was attributed to the relatively wider range of the DSLR camera,which was beneficial for extracting a larger number of ***,the DSLR camera procured more realistic images than the ***,when the compressive strength of concrete was evaluated using the DCNN employing a DSLR camera,time and cost were reduced,whereas the usefulness ***,an indirect comparison of the accuracy of the DCNN with that of existing non-destructive methods for evaluating the strength of concrete proved the reliability of DCNN-derived concrete strength *** addition,it was determined that the DCNN used for concrete strength evaluations in this study can be further expanded to detect and evaluate various deteriorative factors that affect the durability of structures,such as salt damage,carbonation,sulfation,corrosion,and freezing-thawing.

关键词： Deep convolutional neural network(DCNN) non-destructive testing(NDT) concrete compressive strength digital single-lens reflex(DSLR)camera microscope

Extraction and Purification of Depigmenting Agents from Chinese Plants

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Chemical Research in Chinese Universities 2006年第2期22卷 162-167页

作者： ahn So-young ROW Kyung-ho KIM Eun-ki School of Chemical and Biological Engineering Center for Advanced Bioseparation Technology Inha University Nam-Ku Incheon 402-751 Korea

Depigmenting agents were solvent-extracted and purified by preparative and analytical HPLC from three Chinese plants; Chrysanthemum morifolium Ramat（ Xizang Caijuhua）, Rhodiola sachalinensis, and Terminalia chebula Retzius. Four fractions obtained from the ethyl ether layer of C. m. Rama and two fractions from the ethyl acetate layer of Rhodiola salientness show depigmenting effects. At 8 200, the ethyl acetate layers of Chrysanthemum morifolium Ramat, Rhodiola sachalinensis and the methanol extract of Terminalia chebula Retzius, can inhibit the melanin production of mouse B16 melanoma cells by 92%, 60% and 90%, respectively, whereas 46% inhibition was observed by commercially available depigmenting agents（arbutin）. These results show the potential of these three Chinese plants as a novel resource for depigmenting agents in the cosmetic industry.

关键词： Chrysanthemum Morifolium Ramat Rhodiola Sachalinensis Terminalia Chebula Retzius Melanin Inhibitory Effect HPLC

Comparison of Missing Data Imputation Methods in Time Series Forecasting

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Computers, Materials & Continua 2022年第1期70卷 767-779页

作者： Hyun ahn Kyunghee Sun Kwanghoon Pio Kim Division of Software Convergence Hanshin UniversityGyeonggi18101Korea Contents Convergence Software Research Institute Kyonggi UniversityGyeonggi16227Korea Division of AI Computer Science and Engineering Kyonggi UniversityGyeonggi16227Korea

Time series forecasting has become an important aspect of data analysis and has many real-world ***,undesirable missing values are often encountered,which may adversely affect many forecasting *** this study,we evaluate and compare the effects of imputationmethods for estimating missing values in a time *** approach does not include a simulation to generate pseudo-missing data,but instead perform imputation on actual missing data and measure the performance of the forecasting model created *** an experiment,therefore,several time series forecasting models are trained using different training datasets prepared using each imputation ***,the performance of the imputation methods is evaluated by comparing the accuracy of the forecasting *** results obtained from a total of four experimental cases show that the k-nearest neighbor technique is the most effective in reconstructing missing data and contributes positively to time series forecasting compared with other imputation methods.

关键词： Missing data imputation method time series forecasting LSTM

Methoprene does not affect juvenile hormone titers in honey bee （Apis mellifera） workers

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Insect Science 2018年第2期25卷 235-240页

作者： Zachary Y. Huang Stephanie Lin Kiheung ahn Department of Entomology Michigan State University East Lansing Michigan USA Ecology Evolutionary Biology and Behavior Michigan State University East Lansing Michigan USA BEACON Center for the Study of Evolution in Action Michigan State University East Lansing Michigan USA and 4High School Honors Science Program 2007 Michigan State University East Lansing Michigan USA

Methoprene, a juvenile hormone （JH） analog, is a widely used insecticide that also accelerates behavioral development in honey bees （Apis mellifera）. JH regulates the transition from nursing to foraging in adult worker bees, and treatment with JH or methoprene have both been shown to induce precocious foraging. To determine how methoprene changes honey bee behavior, we compared JH titers ofmethoprene-treated and untreated bees. Behavioral observations confirmed that methoprene treatment significantly increased the number of precocious foragers in 3 out of 4 colonies. In only 1 out of 4 colonies, however, was there a significant difference in JH titers between the methoprene- treated and control bees. Further, in all 4 colonies, there was no significant differences in JH titers between precocious and normal-aged foragers. These results suggest that methoprene did not directly affect the endogenous JH secreted by corpora allata. Because methoprene caused early foraging without changing workers＇ JH titers, we conclude that methoprene most likely acts directly on the JH receptors as a substitute for JH.

关键词： behavioral development juvenile hormone analog juvenile hormone metho-prene precocious foraging

Thrust and Swimming Speed Analysis of Fish Robot with Non-uniform Flexible Tail

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Journal of Bionic Engineering 2016年第1期13卷 73-83页

作者： Phi Luan Nguyen Byung Ryong Lee Kyoung Kwan ahn School of Mechanical Engineering University of Ulsan Ulsan Korea

We present a dynamic model of a fish robot with a Non-uniform Flexible Tail （NFT）. We investigate the tendencies of the thrust and swimming speed when the input driving moment changes. Based on the proposed dynamic model of the NFT, we derive the thrust estimation, equation of motion, and performance evaluation of a fish robot with a NFT. By defining the optimal stiffness of the NFT in simulation, a fish robot prototype is then designed and fabricated. A series of experiments are performed to verify the proposed model. Experiment results are in good agreement with simulation data. The results show that the thrust and swimming speed of the fish robot are proportional to the amplitude of the driving moment. There are two resonant fre- quencies （f = 1.4 Hz and 2.2 Hz）, the maximum thrust and swimming speed （about 0.7 BL.s-1） are found to be around f = 1.4 Hz. The above results inidicate the proposed model is suitable for predicting the behavior, thrust and swimming speed of a fish robot with a NFT.

关键词： fish robot flexible tail dynamic modeling swimming speed thrust Froude efficiency

Uniportal video-assisted thoracoscopic fissureless right upper lobe anterior segmentectomy for inflammatory myofibroblastic tumor:A case report

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World Journal of Clinical Cases 2024年第2期12卷 425-430页

作者： Seha ahn Youngkyu Moon Department of Thoracic and Cardiovascular Surgery Eunpyeong St.Mary’s HospitalCollege of MedicineThe Catholic University of KoreaSeoul 03312South Korea

BACKGROUND Inflammatory myofibroblastic tumors(IMTs)are exceptionally rare neoplasms with intermediate malignant *** is the accepted treatment option,aiming for complete resection with clear *** SUMMARY A 39-year-old woman presented with a growing solitary pulmonary nodule measuring 2.0 cm in the right upper lobe(RUL)of the *** patient underwent a RUL anterior segmentectomy using uniportal video-assisted thoracoscopy.A preliminary tissue diagnosis indicated malignancy;however,it was later revised to an *** to the absence of a minor fissure between the right upper and middle lobes,an alternative resection approach was ***,we utilized indocyanine green injection to aid in delineating the intersegmental *** an uneventful recovery,the patient was discharged on the third postoperative ***,annual chest tomography scans were scheduled to monitor for potential local *** This case underscores the challenges in diagnosing and managing IMTs,showing the importance of accurate pathologic assessments and tailored surgical strategies.

关键词： Uniportal video-assisted thoracoscopic surgery Fissureless Anterior segmentectomy Inflammatory fibroblastic tumor Case report

Ultrasonographic findings of re-epithelialized skin after partial-thickness burns

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Burns & Trauma 2018年第3期6卷 219-227页

作者： Jong Dae Kim Suk Joon Oh Sun Gyu Kim Song Vogue ahn Yu Jin Jang Ban seok Yang Ji Yun Jeong Kwang Jo Kim Department of Burn Reconstructive Surgery Bestian Seoul HospitalDogok-ro 429Gangnam-guSeoulRepublic of Korea Department of Health Convergence Ewha Womans UniversityEwhayeodae-gil 52Seodaemun-guSeoulRepublic of Korea Department of Radiology Bestian Seoul HospitalDogok-ro 429Gangnam-guSeoulRepublic of Korea.4Department of General SurgeryBestian Seoul HospitalSeoulRepublic of Korea

Background:This study aimed to investigate the difference between ultrasonographic findings of normal skin and those of re-epithelialized skin after partial-thickness burns and to evaluate the relationship between these findings and clinical outcomes. Methods:This study retrospectively analysed the ultrasound images of re-epithelialized skin after partial-thickness burns and contralateral normal skin from January 2016 to December 2016. A total of 155 lesions from 148 patients were analysed with ultrasound images, and healing time was documented. The scar status of each lesion was evaluated through medical records and photographs. We analysed the difference in ultrasonographic findings between normal skin and re-epithelialized skin after partial-thickness burns and statistically analysed the relationship between healing time, scar status and ultrasonographic findings. Results: The re-epithelialized skin after partial-thickness burns was significantly thicker than the contralateral normal skin, and the echogenicity was significantly lower. The ultrasound images of the re-epithelialized skin after partial-thickness burns showed the characteristic findings of low-echogenic bands (LEB), and the proportion of LEB thickness is strongly correlated with healing time. In the multivariate analysis of scar status, only the proportion of LEB thickness was statistical y significant. Conclusion:In this study, we found that there were ultrasonographic differences between re-epithelialized skin after partial-thickness burns and normal skin and that an LEB of varying thickness was formed after re-epithelialization. The thickness of the LEB in re-epithelialized skin after partial-thickness burns increased with healing time and was related to scar status.

关键词： Partial-thickness burn Ultrasonography Low-echogenic band Healing time Scar Re-epithelialized skin

Minimal circumscribed Hermitian ellipsoid of Hartogs domains and an application to an extremal problem

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Science China Mathematics 2009年第8期52卷 1699-1716页

作者： ahn Heung-ju PARK Jong-do Department of Mathematical Sciences Seoul National University School of Mathematics Korea Institute for Advanced Study Hoegiro 87 Dongdaemun-gu Seoul 130-722 Korea

In this paper we construct circumscribed Hermitian ellipsoids of Hartogs domains of least volume and as an application, we obtain the Carathéodory extremal mappings between the Hartogs domains and the unit ball, and ... 详细信息

关键词： Hartogs domain minimal circumscribed Hermitian ellipsoid extremal problem 32H02 32F45

Severe prelenticular membrane formation on the surface of a hydrophilic acrylic intraocular lens after cataract surgery in an eye with an Ahmed valve implant

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International Journal of Ophthalmology(English edition) 2015年第2期8卷 430-432页

作者： Yong-Sun ahn Jin A Choi Department of Ophthalmology St. Vincent Hospital The College of Medicine Catholic University of Korea

Dear Sir,Iam Yong-Sun ahn,from the Department of Ophthalmology of *** Hospital of Suwon,Kyungki-do,South *** are a common problem in eyes with a glaucoma drainage device(GDD),because tube shunt surgery increases the incidence and progression of cataracts[1].An Ahmed valve,the most commonly inserted GDD,is composed of a silicone tube connected to a flat plate sewn to the sclera,and aqueous humor flows from the

关键词： IOL Severe prelenticular membrane formation on the surface of a hydrophilic acrylic intraocular lens after cataract surgery in an eye with an Ahmed valve implant body Figure