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Transactions of Nonferrous Metals Society of China 2024年

作者： Yeongjung Kim Yong-Sung Eom Kwang-seong choi Jong-Hyun Lee Department of Materials Science and Engineering， Seoul National University of Science and Technology， 232 Gongneung-ro Low-Carbon Integration Tech， Creative Research Section， ETRI， 218 Gajeong-ro Materials Research Institute for Future Convergence， Seoul National University of Science and Technology， 232 Gongneung-ro

Four types of submicron Ag-coated Cu particles with different Ag contents were prepared as sintering paste fillers， and the Ag contents of the particles were measured to be 10， 20， 30， and 40 wt%. Four types of particles （in order of increasing Ag content: A10， A20， A30， and A40） were surface-modified with stearic acid， to suppress the Ag shell dewetting and improve sinterability. The surface-modified particles were mixed with a polyol-based solvent to fabricate a resin-free paste. Subsequently， the pastes were screen-printed onto a slide glass and sintered at 250 ℃ in a nitrogen atmosphere for 1–10 min to form an electrode. The electrical resistivity of the sintered film as a function of sintering time was measured using a four-point probe. All the four surface-modified Cu@Ag particles with different Ag contents exhibited decreased electrical resistivity. Particularly， the largest difference in values after and before the surface modification was observed for A40 with the highest Ag content; the electrical resistivities of the initial and surface-modified particles were 1.51×10-4and 6.67×10-5Ω·cm， respectively， after sintering for 10 min. The findings of this study confirmed that the surface modification using stearic acid effectively suppressed the dewetting of the Ag shell and improved the sinterability of the submicron Cu@Ag particles.

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Experience of limited pancreatic head resection for management of branch duct intraductal papillary mucinous neoplasm in a single center

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World Journal of Gastroenterology 2009年第23期15卷 2904-2907页

作者： Kwang Yeol Paik seong Ho choi Department of Surgery Kepco Medical Foundation Hanil General Hospital #388-1 Ssangmoon-Dong Dobong-Gu Seoul 132-033 South Korea Department of Surgery Samsung Medical Center College of Medicine Sungkyunkwan University #50 Irwon-Dong Gangnam-Gu Seoul 135-710 South Korea

AIM: To share our surgical experience and the outcome of limited pancreatic head resection for the management of branch duct intraductal papillary mucinous neoplasm (IPMN). METHODS: Between May 2005 and February 2008, nine limited pancreatic head resections (LPHR) were performed for IPMN of the pancreatic head. We reviewed the nine patients, retrospectively. RESULTS: Tumor was located in the uncinate process of the pancreas in all nine patients. Three patients had stents inserted in the main pancreatic duct due to injury. The mean size of tumor was 28.4 mm. Postoperative complications were found in f ive patients: 3 pancreatic leakages, a pancreatitis, and a duodenal stricture. Pancreatic leakages were improved by external drainage. No perioperative mortality was observed and all patients are recorded alive during the mean follow-up period of 17.2 mo. CONCLUSION: In selected patients after careful evaluation, LPHR can be used for the treatment of branch duct type IPMN. In order to avoid pancreatic ductal injury, preand intra-operative defi nite localization and careful operative techniques are required.

关键词： Limited pancreatic head resection Branchduct type Intraductal papillary mucinous neoplasm

Grade-4 commercially pure titanium with ultrahigh strength achieved by twinning-induced grain refinement through cryogenic deformation

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Journal of Materials Science & Technology 2021年第7期66卷 193-201页

作者： seong-Woo choi Jae Sukjeong Jong Woo Won Jae Keun Hong Yoon Suk choi Titanium Department.Korea Institute of Materials Science Changwon51508Republic of Korea School of Materials Science and Engineering Pusan National UniversityPusan.46241Republic of Korea Materials and Manufacturing Development Team Doosan Heavy Industries and ConstructionChangwon51711Republic of Korea

The yield strength of commercially pure(CP) Ti of ASTM grade 4, the strongest among all the CP-Ti grades, is too low for structural applications that require high-strength materials. Here, we demonstrate the strengthening of grade-4 CP Ti by cryogenic-temperature rolling(CTR), which enables deformation twinning in grade-4 CP Ti to achieve twinning-induced grain refinement. CTR activated {11.22} twinning and {10.12} twinning, which are the most common twinning systems in pure Ti, whereas room-temperature rolling(RTR) did not activate any twinning system. CTR with imposing an area reduction of just 30% significantly increased the yield strength of the CP Ti to 946 MPa, which is not achievable through typical processes performed at or above room temperature and is comparable to that of commercial Ti-6 Al-4 V. The significant increase in strength was due to microstructural strengthening caused by twinning-induced grain refinement, combined with dislocation accumulation. In contrast to RTR, CTR greatly increased the stress concentration at grain boundaries(GBs), which caused the unusual activation of twinning in the grade-4 CP Ti by facilitating twin nucleation at GBs. The stress concentration increased because CTR activated the slip to a lesser extent compared to RTR, thereby reducing the strain compatibility between neighboring grains. These results will contribute to development of ultrahigh-strength CP Ti and may thereby extend its use to structural applications that require high-strength materials.

关键词： Titanium Twinning Cryogenic deformation Grain refinement Tensile properties

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Management of bleeding from pseudoaneurysms following pancreaticoduodenectomy

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World Journal of Gastroenterology 2010年第10期16卷 1239-1244页

作者： Hyung Geun Lee Jin Seok Heo seong Ho choi Dong Wook choi Department of Surgery Samsung Medical CenterSungkyunkwan University School of Medicine

AIM:To review the clinical course and the management of pseudoaneurysms ***: Medical records of 907 patients who underwent pancreaticoduodenectomies from January 1995 to May 2007 were evaluated retrospectively. The clinical course, management strategy, and outcome of ruptured pseudoaneurysms cases were ***: Twenty-seven (3.0%) of 907 cases had post-operative hemorrhage from ruptured pseudoan-eurysms. Pancreatic fistula was evident in 12 (44%) cases. Sentinel ble...

关键词： Pseudoaneurysm Angi-ography Embolization Stent graft

Diagnosis of Middle Ear Diseases Based on Convolutional Neural Network

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Computer Systems Science & Engineering 2023年第8期46卷 1521-1532页

作者： Yunyoung Nam seong Jun choi Jihwan Shin Jinseok Lee Department of Computer Science and Engineering Soonchunhyang UniversityAsan31538Korea Department of Otolaryngology-Head and Nech Surgery Soonchunhyang University College of MedicineCheonan HospitalCheonan31151Korea Department of Biomedical Engineering Kyung Hee UniversityYonginKorea

An otoscope is traditionally used to examine the eardrum and ear canal.A diagnosis of otitis media(OM)relies on the experience of *** an examiner lacks experience,the examination may be difficult and *** paper presents an ear disease classification method using middle ear images based on a convolutional neural network(CNN).Especially the segmentation and classification networks are used to classify an otoscopic image into six classes:normal,acute otitis media(AOM),otitis media with effusion(OME),chronic otitis media(COM),congenital cholesteatoma(CC)and traumatic perforations(TMPs).The Mask R-CNN is utilized for the segmentation network to extract the region of interest(ROI)from otoscopic *** extracted ROIs are used as guiding features for the *** classification is based on transfer learning with an ensemble of two CNN classifiers:EfficientNetB0 and *** proposed model was trained with a 5-fold cross-validation *** proposed method was evaluated and achieved a classification accuracy of 97.29%.

关键词： Otitis media convolutional neural network acute otitis media otitis media with effusion chronic otitis media congenital cholesteatoma traumatic perforation Mask R-CNN

Integrating Deep Learning and Machine Translation for Understanding Unrefined Languages

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Computers, Materials & Continua 2022年第1期70卷 669-678页

作者： Hong Geun Ji Soyoung Oh Jina Kim seong choi Eunil Park Department of Applied Artificial Intelligence Sungkyunkwan UniversitySeoul03063Korea Raon Data Seoul03073Korea Department of Computer Science and Engineering University of MinnesotaMinneapolis55455MNUSA

In the field of natural language processing(NLP),the advancement of neural machine translation has paved the way for cross-lingual ***,most studies in NLP have evaluated the proposed language models on well-refined *** investigatewhether amachine translation approach is suitable for multilingual analysis of unrefined datasets,particularly,chat messages in *** order to address it,we collected the dataset,which included 7,066,854 and 3,365,569 chat messages from English and Korean streams,*** employed several machine learning classifiers and neural networks with two different types of embedding:word-sequence embedding and the final layer of a pre-trained language *** results of the employed models indicate that the accuracy difference between English,and English to Korean was relatively high,ranging from 3%to 12%.For Korean data(Korean,and Korean to English),it ranged from 0%to 2%.Therefore,the results imply that translation from a low-resource language(e.g.,Korean)into a high-resource language(e.g.,English)shows higher performance,in contrast to vice *** implications and limitations of the presented results are also *** instance,we suggest the feasibility of translation from resource-poor languages for using the tools of resource-rich languages in further analysis.

关键词： Twitch multilingual machine translation machine learning

Potential risk factors for nonalcoholic steatohepatitis related to pancreatic secretions following pancreaticoduodenectomy

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World Journal of Gastroenterology 2011年第32期17卷 3716-3723页

作者： Sun Choon Song seong Ho choi Dong Wook choi Jin Seok Heo Woo Seok Kim Min Jung Kim Department of Surgery Samsung Medical Center Sungkyunkwan University School of Medicine

AIM: To identify risk factors for nonalcoholic steatohepatitis following pancreaticoduodenectomy, with a focus on factors related to pancreatic secretions. METHODS: The medical records of 228 patients who had a pancreaticoduodenectomy over a 16-mo period were reviewed retrospectively. The 193 patients who did not have fatty liver disease preoperatively were included in the final analysis. Hepatic steatosis was diagnosed using the differences between splenic and hepatic attenuation and liver-to-spleen attenuation as measured by non-enhanced computed tomography. RESULTS: Fifteen patients (7.8%) who showed postoperative hepatic fatty changes were assigned to Group A, and the remaining patients were assigned to Group B. Patient demographics, preoperative laboratory findings (including levels of C-peptide, glucagon, insulin and glucose tolerance test results), operation types, and final pathological findings did not differ significantly between the two groups; however, the frequency of pancreatic fistula (P = 0.020) and the method of pancreatic duct stenting (P = 0.005) showed significant differences between the groups. A multivari- ate analysis identified pancreatic fistula (HR = 3.332, P = 0.037) and external pancreatic duct stenting (HR = 4.530, P = 0.017) as independent risk factors for the development of postoperative steatohepatitis. CONCLUSION: Pancreatic fistula and external pancreatic duct stenting were identified as independent risk factors for the development of steatohepatitis following pancreaticoduodenectomy.

关键词： Nonalcoholic fatty liver diseases Nonalcoholic steatohepatitis Pancreatic duct stenting Pancreatic fistula Pancreatic surgery

Rapid Preparation of Monolithic Columns for Capillary Electrochromatography Separation

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Chinese Chemical Letters 2006年第6期17卷 813-816页

作者： Wen Jun GONG Yi Jun ZHANG Yu Ping ZHANG seong Ho choi Henan Institute of Science and Technology Xinxiang 453003 Department of Chemistry Hannam University Daejon South Korea

Fritless packed silica gel columns were prepared using sol-gel technology, The part of a 75 μm i.d. capillary was filled with a mixture of methacryloxypropyltrimethoxysilane, toluene and hydrochloric acid. Four different photoinitiators such as benzoin methyl ether, Irgacure 819, Irgacure 1700 and Irgacure 1800 were added in the presence or absence of sodium dodecyl sulfate during the polymerization process. The above eight solutions were irradiated at 365 nm about 5-10 min to prepare the porous monolithic sol-gel columns by a one-step process.

关键词： Monolithic columns electrochromatography photopolymerized sol-gel.

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Effects of acupuncture stimulation on brain activation induced by cue-elicited alcohol craving

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Neural Regeneration Research 2022年第5期17卷 1059-1064页

作者： Hyeok Gyu Kwon seong Hun choi Joon Ho Seo Chae Ha Yang Mi Young Lee Department of Physical Therapy College of Health ScienceEulji UniversityGyeonggiRepublic of Korea Department of Anatomy and Histology College of Oriental MedicineDaegu Haany UniversityGyeongsanRepublic of Korea Department of Rehabilitation Gyeongbuk Regional Rehabilitation HospitalGyeongsanRepublic of Korea Department of Physiology College of Korean MedicineDaegu Haany UniversityDaeguRepublic of Korea Department of Physical Therapy College of Biomedical ScienceDaegu Haany UniversityGyeongsanRepublic of Korea

Acupuncture has been shown to be effective on alcohol use ***,the underlying mechanism remains poorly *** investigate the effects of Shenmen(HT7)acupoint on brain activation induced by cue-elicited alcohol craving,30 right-handed healthy light to moderate alcohol drinkers were recruited from the *** were randomly assigned to undergo acupuncture either at HT7(experimental acupoint,n=15)or Jingqu(LU8,control acupoint,n=15)*** randomized controlled study was performed in Daegu Haany University and Daegu-Gyeongbuk Medical Innovation Foundation,Republic of *** and data collection were conducted from December 2018 to May *** results showed that after acupuncture at HT7 acupoint,the activation of orbitofrontal cortex and dorsolateral prefrontal cortex was greatly increased,while the activation of dorsolateral prefrontal cortex was obviously reduced,and subject's craving for alcohol was reduced when he/she seeing alcohol-related video clips involving various alcohols(beer,wine,or soju)or drinking *** at HT7 more greatly reduced subject's alcohol cravings than acupuncture at LU8 *** findings suggest that acupuncture can improve the self-control of mild to moderate social drinkers through the activation of the orbitofrontal cortex and dorsolateral prefrontal cortex,thereby reducing the craving for *** study protocol was approved by the Institutional Review Board of Daegu Haany University Korean Medicine Hospital,Republic of Korea(approval ***-D-18026-PRO-02)on November 30,2018.

关键词： acupuncture addiction alcohol brain activation craving cue functional MRI Shenmen(HT7)acupoint

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Carcinoma of the middle bile duct:Is bile duct segmental resection appropriate?

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World Journal of Gastroenterology 2009年第47期15卷 5966-5971页

作者： Hyung Geun Lee Sang Hoon Lee Dong Do Yoo Kwang Yeol Paik Jin Seok Heo seong Ho choi Dong Wook choi Department of Surgery Samsung Medical CenterSungkyunkwan University School of MedicineSeoul 135-710South Korea

AIM:To compare survival between bile duct segmental resection(BDSR)and pancreaticoduodenectomy(PD) for treating distal bile duct cancers. METHODS:Retrospective analysis was conducted for 45 patients in a BDSR group and for 149 patients in a PD group. RESULTS:The T-stage(P<0.001),lymph node invasion (P=0.010)and tumor differentiation(P=0.005)were significant prognostic factors in the BDSR *** 3-and 5-year overall survival rates for the BDSR group and PD group were 51.7%and 36.6%,respectively and 46.0%and 38.1%,respectively(P=0.099).The BDSR group and PD group did not show any significant difference in survival when this was adjusted for the TNM *** 3-and 5-year survival rates were: stageⅠa[BDSR(100.0%and 100.0%)vs PD(76.9% and 68.4%)(P=0.226)];stageⅠb[BDSR(55.8% and 32.6%)vs PD(59.3%and 59.3%)(P=0.942)]; stageⅡb[BDSR(19.2%and 19.2%)vs PD(31.9%and 14.2%)(P=0.669)]. CONCLUSION:BDSR can be justified as an alternative radical operation for patients with middle bile duct inselected patients with no adjacent organ invasion and resection margin is negative.

关键词： Bile duct cancer Segmental resection Pancreaticoduodenectomy