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Development of analysis model for geometric error in turning processes

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Journal of Central South University 2011年第3期18卷 711-717页

作者： LEE Mun-jae LEE Choon-man Department of Mechanical Design and manufacturing Engineering Changwon National University

A finite element model was established for analyzing the geometric errors in turning operations and a two-step analyzing process was proposed. In the first analyzing step, the cutting force and the cutting heat for the cutting conditions were obtained using the AdvantEdge. Also, the deformation of a workpiece was estimated in the second step using the ANSYS. The deformation was analyzed for a 150 mm-long workpiece at three different measuring points, such as 10, 70 and 130 mm from a reference point, and the amounts of the deformation were compared through experiments. /n the results of the comparison and analysis, the values obtained from these comparison and analysis represent similar tendencies. Also, it is verified that their geometric errors increase with the increase in temperature. In addition, regarding the factors that affect the deformation of a workpiecc, it can be seen that the geometric error in the lathe is about 15%, the error caused by the cutting force is about 10%, and the deformation caused by the heat is about 75%.

关键词： geometric error machining accuracy finite element analysis turning cutting force, cutting temperature

Development of two-axis control index table driven by direct drive motors

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Journal of Central South University 2011年第6期18卷 1962-1968页

作者： KIM jae-hyun LEE Choon-man School of Mechatronics Changwon National University

The stability and reliability of a tilting index table should be considered at the design stage. A design method for the lightweight and improvement of the stability of the structure in a tilting index table was proposed using a commercial analysis program, ANSYS Workbench 12, by analyzing the static-thermal characteristics of the developed high-accuracy tilting index table at its design stage. The results of the performed structural analysis show that the maximum stress is generated at the stock tail part. An optimum design for the stock tail part was carried out to reduce the maximum stress and deformation. Also, the design variables were determined by considering the support of the stock tail part for the C-axis body. In the comparison of the results before and after the optimization, the maximum deformation and stress are improved by 2.8% and 8%, respectively.

关键词： tilting index table structural analysis modal analysis thermal analysis optimum design

Prothrombin kringle-2, a mediator of microglial activation: new insight in Alzheimer’s disease pathogenesis

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Neural Regeneration Research 2022年第12期17卷 2675-2676页

作者： jae man Lee Sang Ryong Kim Department of Biochemistry and Cell Biology Cell and Matrix Research InstituteSchool of MedicineKyungpook National UniversityDaeguKorea Brain Science and Engineering Institute Kyungpook National UniversityDaeguKorea School of Life Sciences BK21 FOUR KNU Creative BioResearch GroupInstitute of Life Science and BiotechnologyKyungpook National UniversityDaeguKorea

Microglial activation in Alzheimer’s disease(AD):In 1907,*** Alzheimer,a Bavarian-born German psychiatrist and neuropathologist,published an article describing the clinical and neuropathological features of an unclassified psychiatric *** disorder was later named AD and is currently the most common brain disorder(Takata et al.,2021).AD involves the accumulation of amyloid-β(Aβ)and hyperphosphorylated tau proteins in the brain,which are associated with senile plaques and neurofibrillary tangles,respectively(Vergara et al.,2019;Takata et al.,2021).AD is characterized by cognitive impairment and memory loss with hippocampal neurodegeneration(Kim et al.,2021).

关键词： Alzheimer Aβ tau

Multi-stage optimum design of magazine type automatic tool changer arm

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Journal of Central South University 2012年第1期19卷 174-178页

作者： KIM jae-Hyun LEE Choon-man School of Mechatronics Changwon National UniversityChangwon 641-773Korea

To enhance machining efficiency,tool change time has to be ***,for an automatic tool changer attached to a machining center,the tool change time is to be *** the automatic tool changer is a main part of the machining center as a driving *** static attributes of the automatic tool changer using the commercial code,ANSYS Workbench V12,were tried to *** the optimum design of automatic tool changer arm was proposed by performing the multi-stage optimum *** shape optimization of the automatic tool changer was proposed and the result was verified to obtain acceptable *** is possible to obtain an optimized model in which the maximum deformation,maximum stress,and mass are reduced by 10.46%,12.89% and 9.26%,respectively,compared with those of the initial ***,the results between conventional method by the design of experiments and proposed method by the multi-stage optimum design method were compared.

关键词： automatic tool changer optimum design structural analysis exchange arm

Development of CAD/CAM system and profile measuring device for CNC grinding machine to obtain an optimal grinding speed

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Journal of Central South University 2011年第1期18卷 146-152页

作者： LIM Sang-Heon KIM jae-Hyun LEE Choon-man Agency of Promoting Technology Innovation Gyeongnam TechnoparkChangwon 641-465Korea School of Mechatronics Changwon National University

Cam mechanics is one of the most popular devices for generating irregular motions and is widely used in automatic equipment,such as textile machines,internal combustion engines,and other automatic *** order to obtain a positive motion from the follower using a rotating cam,its shape should be correctly designed and *** development of an adequate CAD/CAM system for a cam profile CNC grinding machine is necessary to manufacture high-precision *** purpose of this study is the development of a CAD/CAM system and profile measuring device for a CNC grinding machine to obtain an optimal grinding speed with a constant surface *** types of disk cams were manufactured using the proposed algorithm and procedures to verify effectiveness of the developed CAD/CAM system.

关键词： cam CAD/CAM system CNC grinding machine optimal grinding speed

Characterization and recombinant protein expression of ferritin light chain homologue in the silkworm, Bombyx mori

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Insect Science 2014年第2期21卷 135-146页

作者： Sun Mee Hong Hiroaki Mon jae man Lee Takahiro Kusakabe Department of Research and Development Gyeongbuk Institute for Marine Bioindustry (GIMB) Hujeong 688-3 Uljin 767-813 Korea Laboratory of Silkworm Science Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences Hakozaki 6-10-1 Fukuoka 812-8581 Japan

The silkworm genome encodes three iron storage proteins or ferritins, FerlHCH, Fer2LCH, and Fer3HCH. Probing our EST library constructed from 1-day- old silkworm eggs revealed only Fer2LCH mRNA, which encoded for a protein with a predicted putative N-glycosylation site. Developmental and tissue expression analyses dur- ing embryogenesis revealed that Fer2LCH mRNA was abundant from 6 h to 6 days after oviposition. Transcriptional expression of Fer2LCH during the postembryonic stage is also high in the larval fat body and mid-gut, and then is upregulated in all pupal tissues tested. We found that Fer2LCHmRNA contains an iron-responsive element, suggesting this fer- ritin subunit is subject to translational control. Although ferritin expression has been shown to increase following immune challenge in other insects, the levels of Fer2LCH mRNA were not significantly induced following viral or bacterial infection ofBombyx mori. Using a baculovirus expression system we expressed recombinant BmFer2LCH protein, which was detectable in the cytoplasmic fraction, likely in a compartment of the secretory path- way, and was shown to undergo posttranslational modifications including N-glycosylation. In particular, rBmFer2LCH carbohydrate chains were composed ofmannose and GlcNAc. We suggest that Fer2LCH is important for iron homeostasis and maintaining normal organ function in silkworms.

关键词： baculovirus expression system Bombyx mori embryo Fer2LCH ironstorage protein N-glycosylation

Synergistic passivation of MAPbI_(3) perovskite solar cells by compositional engineering using acetamidinium bromide additives

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Journal of Energy Chemistry 2021年第8期30卷 755-762,I0016页

作者： Kyungeun Jung Weon-Sik Chae jae Won Choi Ki Chul Kim man-Jong Lee Department of Chemistry Konkuk University143-701 SeoulSouth Korea Department of Advanced Technology Fusion Konkuk University143-701 SeoulSouth Korea Analysis Research Division Daegu CenterKorea Basic Science Institute702-701 DaeguSouth Korea Division of Chemical Engineering Konkuk University05029 SeoulSouth Korea

For the global commercialization of highly efficient and stable perovskite solar cells(PSCs),it is necessary to effectively suppress the formation of various defects acting as nonradiative recombination sources in perovskite light-harvesting *** defects between the charge-selective layer and the perovskite are easily formed in the solution process used to fabricate perovskite *** addition,owing to the difference in thermal expansion coefficients between the substrate and the perovskite film,internal residual tensile stress inevitably occurs,resulting in increased nonradiative ***,a simple compositional engineering scheme for realizing efficient and stable PSCs,which incorporates acetamidinium bromide(AABr)as an additive into the MAPbI_(3) lattice,is *** an additive,AABr has been found to provide synergistic multiple passivation for both internal and interfacial *** was found to effectively release the tensile strain of the MAPbI_(3) film by forming a structure stabilized by NH-I hydrogen bonds,as evidenced by calculations based on density functional theory(DFT).Furthermore,the incorporated AABr additives created a charge carrier recombination barrier to enhance charge collection capability by reducing interfacial ***,a power conversion efficiency(PCE)of 20.18%was achieved using a planar device employing AABr-incorporated MAPbI_(3).This was substantially higher than the 18.32% PCE of a pristine MAPbI_(3)-based ***,unencapsulated PSCs using AABr-incorporated MAPbI_(3) absorbers exhibited excellent long-term stability,maintaining>95% of initial PCE up to 1200 hours in ambient air.

关键词： Acetamidinium bromide Planar perovskite solar cell Tensile stress Interface passivation Recombination barrier

Semantic Segmentation by Using Down-Sampling and Subpixel Convolution: DSSC-UNet

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Computers, Materials & Continua 2023年第4期75卷 683-696页

作者： Young-man Kwon Sunghoon Bae Dong-Keun Chung Myung-jae Lim Department of Medical IT Eulji University553Sanseong-daeroSujeong-guSeongnam-siGyeonggi-do13135Korea

Recently, semantic segmentation has been widely applied toimage processing, scene understanding, and many others. Especially, indeep learning-based semantic segmentation, the U-Net with convolutionalencoder-decoder architecture is a representative model which is proposed forimage segmentation in the biomedical field. It used max pooling operationfor reducing the size of image and making noise robust. However, instead ofreducing the complexity of the model, max pooling has the disadvantageof omitting some information about the image in reducing it. So, thispaper used two diagonal elements of down-sampling operation instead ofit. We think that the down-sampling feature maps have more informationintrinsically than max pooling feature maps because of keeping the Nyquisttheorem and extracting the latent information from them. In addition,this paper used two other diagonal elements for the skip connection. Indecoding, we used Subpixel Convolution rather than transposed convolutionto efficiently decode the encoded feature maps. Including all the ideas, thispaper proposed the new encoder-decoder model called Down-Sampling andSubpixel Convolution U-Net (DSSC-UNet). To prove the better performanceof the proposed model, this paper measured the performance of the UNetand DSSC-UNet on the Cityscapes. As a result, DSSC-UNet achieved89.6% Mean Intersection OverUnion (Mean-IoU) andU-Net achieved 85.6%Mean-IoU, confirming that DSSC-UNet achieved better performance.

关键词： Semantic segmentation encoder-decoder U-Net DSSC-UNet subpixel convolution down-sampling

Risk factors for complications associated with upper gastrointestinal foreign bodies

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World Journal of Gastroenterology 2015年第26期21卷 8125-8131页

作者： Kyong Hee Hong Yoon jae Kim jae Hak Kim Song Wook Chun Hee man Kim jae Hee Cho Division of Gastroenterology Department of Internal MedicineDongguk University Ilsan HospitalGraduate School Division of Gastroenterology Department of Internal MedicineGachon University Gil Medical Center Division of Gastroenterology Department of Internal MedicineMyongji Hospital Division of Gastroenterology and Hepatology Department of Internal MedicineYonsei University Wonju College of Medicine

AIM: To investigate predictive risk factors associated with complications in the endoscopic removal of foreign bodies from the upper gastrointestinal ***: We retrospectively reviewed the medical records of 194 patients with a diagnosis of foreign body impaction in the upper gastrointestinal tract,confirmed by endoscopy,at two university hospital in South *** demographic data,including age,gender,intention to ingestion,symptoms at admission,and comorbidities,were *** features of the foreign bodies,such as type,size,sharpness of edges,number,and location,were *** data those were analyzed included duration of foreign body impaction,duration of endoscopic performance,endoscopic device,days of hospitalization,complication rate,30-d mortality rate,and the number of operationsrelated to foreign body ***: The types of upper gastrointestinal foreign bodies included fish bones,drugs,shells,meat,metal,and animal *** locations of impacted foreign bodies were the upper esophagus(57.2%),mid esophagus(28.4%),stomach(10.8%),and lower esophagus(3.6%).The median size of the foreign bodies was 26.2 ± 16.7 *** 194 patients,endoscopic removal was achieved in 189,and complications developed in 51 patients(26.9%).Significant complications associated with foreign body impaction and removal included deep lacerations with minor bleeding(n = 31,16%),ulcer(n = 11,5.7%),perforation(n = 3,1.5%),and abscess(n = 1,0.5%).Four patients underwent operations because of incomplete endoscopic foreign body *** multivariate analyses,risk factors for endoscopic complications and failure were sharpness(HR = 2.48,95%CI: 1.07-5.72; P = 0.034) and a greater than 12-h duration of impaction(HR = 2.42,95%CI: 1.12-5.25,P = 0.025).CONCLUSION: In cases of longer than 12 h since foreign body ingestion or sharp-pointed objects,rapid endoscopic intervention should be provided in patients with ingested foreign bodies.

关键词： Emergency department Foreign body Upper gastrointestinal tract Endoscopy Complication