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Is the AIM65 score useful in predicting outcomes in peptic ulcer bleeding?

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World Journal of Gastroenterology 2014年第7期20卷 1846-1851页

作者： Sung Hoon jung jung Hwan Oh Hye Yeon lee Joon Won Jeong Se Eun Go chan Ran You Eun jung Jeon Sang Wook Choi Division of Gastroenterology Department of Internal MedicineCollege of MedicineThe Catholic University of KoreaSeoul 130-709South Korea

AIM:To evaluate the applicability of AIMS65 scores in predicting outcomes of peptic ulcer ***:This was a retrospective study in a single center between January 2006 and December *** enrolled 522 patients with upper gastrointestinal haemorrhage who visited the emergency *** patients were regarded as those who had rebleeding within 30 d from the first endoscopy as well as those who died within 30 d of visiting the Emergency room.A total of 149 patients with peptic ulcer bleeding were analysed,and the AIMS65 score was used to retrospectively predict the high-risk ***:A total of 149 patients with peptic ulcer bleeding were *** poor outcome group comprised 28 patients[male:23(82.1%)vs female:5(10.7%)]while the good outcome group included 121patients[male:93(76.9%)vs female:28(23.1%)].The mean age in each group was not significantly *** mean serum albumin levels in the poor outcome group were slightly lower than those in the good outcome group(P=0.072).For the prediction of poor outcome,the AIMS65 score had a sensitivity of35.5%(95%CI:27.0-44.8)and a specificity of 82.1%(95%CI:63.1-93.9)at a score of *** AIMS65 score was insufficient for predicting outcomes in peptic ulcer bleeding(area under curve=0.571;95%CI:0.49-0.65).CONCLUSION:The AIMS65 score may therefore not be suitable for predicting clinical outcomes in peptic ulcer *** albumin levels may be a risk factor associated with high mortality in peptic ulcer bleeding.

关键词： Gastrointestinal haemorrhage Peptic ulcer Mortality Morbidity Prognosis

Densification simulation of compacted Al powders using multi-particle finite element method

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中国有色金属学会会刊：英文版 2009年第B9期19卷 68-75页

作者： Kyung-Hun lee jung-Min lee Byung-Min KIM School of Mechanical Engineering Pu san National University

The powder compaction simulations were performed to demonstrate deformation behavior of particles and estimate the effect of different punch speeds and particle diameters on the relative density of powder by a multi-particle finite element model(MPFEM). Individual particle discretized with a finite element mesh allows for a full description of the contact mechanics. In order to verify the reliability of compaction simulation by MPFEM, the compaction tests of porous aluminum with average particle size of 20 μm and 3 μm were performed at different ram speeds of 5, 15, 30 and 60 mm/min by MTS servo-hydraulic tester. The results show that the slow ram speed is of great advantage for powder densification in low compaction force due to sufficient particle rearrangement and compaction force increases with decrease in average particle size of aluminum.

关键词：粉末压实粉末粒子多孔铝有限元法模拟致密化平均粒径有限元模型

High performance of TiO_(2)/Cu_(x)O photoelectrodes for regenerative solar energy storage in a vanadium photoelectrochemical cell

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Green Energy & Environment 2022年第4期7卷 704-711页

作者： Harin Yoo Doohwan lee jung Hyeun Kim Department of Chemical Engineering University of Seoul163 SiripdaeroDongdaemun-guSeoul02504South Korea

Photocatalysts for harvesting solar energy to either electricity or chemical fuels have attracted much attention recently, but they have big obstacles such as wide bandgaps and rapid charge recombinations to overcome for final applications. In this study, we investigates a useful method to utilize vanadium redox pairs, which are commonly applied for vanadium redox flow batteries, to diminish charge recombinations and thus to enhance photocurrent response in regenerative solar energy storage. The results reveal significant improvements in photocurrent density by forming cuprous and cupric oxides in TiO_(2)/Cu_(x)O electrodes under solar AM 1.5 illuminations using the vanadium photoelectrochemical storage cell at 0.025 mol L^(-1) of vanadium redox species in the acid electrolytes. In addition, the stabilized photocurrent density of the copper content optimized TiO_(2)/Cu_(x)O electrodes is almost tripled from the TiO_(2) only electrode because the charge recombinations can be mitigated with the content optimized TiO_(2)/Cu_(x)O electrodes. Therefore, the optimized TiO_(2)/Cu_(x)O electrode results in the highest charge storing performance in the catholyte chamber, and the roles of vanadium redox species are also clearly demonstrated.

关键词： Photocatalyst Photoelectrochemical Copper oxide Charge recombination Redox pairs

Tetradentate Pt(Ⅱ)complex as a singlet exciton sensitizing host for highly efficient green fluorescent organic light-emitting diodes

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Science China Materials 2024年第8期67卷 2618-2627页

作者： Unhyeok Jo Seung chan Kim chan Hee Ryu Kang Mun lee Jae-Min Kim Jun Yeob lee School of Chemical Engineering Sungkyunkwan University2066Seobu-roJangan-guSuwon-siGyeonggi-do 16419Republic of Korea Department of Chemistry Institute for Molecular Science and Fusion TechnologyKangwon National UniversityChuncheonGangwon 24341Republic of Korea Department of Advanced Materials Engineering Chung-Ang University4726Seodong-daeroDaedeok-myeonAnseong-siGyeonggi-do 17546Republic of Korea SKKU Advanced Institute of Nano Technology Sungkyunkwan University2066Seobu-roJangan-guSuwonGyeonggi 16419Republic of Korea SKKU Institute of Energy Science and Technology Sungkyunkwan University2066Seobu-roJangan-guSuwonGyeonggi 16419Republic of Korea

Efficient green fluorescent organic light-emitting diodes were designed with a phosphorescent metal complex as a singlet exciton sensitizing host(SESH)for achieving high efficiency and low efficiency roll-off through exciton and polaron *** Pt(Ⅱ)complex(Pt-Trz)possessing a tetradentate ligand with a bulky blocking group not only suppresses the severe formation of excimer or dimer itself but also transfers radiative excitons to fluorescent dopant *** SESH assisted fluorescence(SESHF)device with Pt-Trz as the host exhibits the maximum external quantum efficiency of 13.3%and a lower efficiency roll-off compared with exciplex host device which is a general approach for harvesting triplet *** exciton dynamics modeling unravels that the SESHF device effectively utilizes triplet excitons in the host by intersystem crossing and resonance energy transfer from the triplet state of the host to the singlet state of the terminal *** quenching rates of the SESHF device are reduced by 11 times for triplet-triplet annihilation and 1.8 times for tripletpolaron annihilation compared with the exciplex device,which demonstrates that Pt-Trz could be a platform to be used as an efficient host for fluorophores.

关键词： singlet annihilation polaron

Lattice Preferred Orientation, Water Content, and Seismic Anisotropy of Orthopyroxene

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Journal of Earth Science 2010年第5期21卷 555-568页

作者： Haemyeong jung Munjae Park Sejin jung Jaeseok lee Tectonophysics Laboratory School of Earth and Environmental Sciences Seoul National University Seoul 151-747 Korea

Lattice preferred orientation （LPO） and seismic anisotropy of orthopyroxene （enstatite） in mantle xenoliths from Spitsbergen, Svalbard, near the Arctic, are studied. LPOs of enstatite were determined using electron backseattered diffraction （EBSD）. We found four types of LPOs of orthopyroxene and defined them as type-AC, -AB, -BC, and -ABC. Type-AC LPO of orthopyroxene is defined as （100） plane aligned subparallel to foliation and [001] axis aligned subparallel to lineation. Type-AB LPO is defined as （100） plane aligned subparallel to foliation and [010] axis aligned subparallel to linea- tion. Type-BC LPO is defined as （010） plane aligned subparallel to foliation and [001] axis aligned subparallel to lineation. Type-ABC LPO is defined as both （100） and （010） planes aligned subparallel to foliation with a girdle distribution of both [100] and [010] axes normal to lineation and [001] axis aligned subparallel to lineation. We report for the first time the type-AB, -BC, and -ABC LPO of orthopyroxerie. We found that the LPO pattern has a correlation with the content of orthopyroxene in the specimen. Nicolet 6700 FTIR （Fourier transformation infrared） study of enstatite showed that type-AC LPO was observed mostly in the samples of enstatite with low water content. It is found that the strength of the LPO of enstatite decreases with increasing water content and has a correlation with the strength of the LPO of olivine： the stronger the LPO of enstatite, the stronger the LPO of olivine. Seismic anisotropy of enstatite was smaller than that of olivine in the same specimen.

关键词： orthopyroxene lattice preferred orientation seismic anisotropy mantle xenolith Spitsbergen FTIR.

Ultra-low concentration of total organic carbon in ultrapure water using ion-exchange resin embedding silanized magnetic nanoparticles

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Journal of Environmental Sciences 2020年第6期32卷 11-17页

作者： jung Joon lee Jihyeon Park Bo-Hyun Kim Sunjong lee Department of Advanced Materials Science and Engineering Sungkyunkwan UniversitySuwon 16419South Korea Korea Institute of Industrial Technology 89 Yangdaegiro-gilIpjang-myeonCheonan-si 31056South Korea

Regeneration of pure water is an important issue not only for the healthy life but also for the fine control of precise processes in various *** important issue in ultrahigh purified water is to reduce the amount of total organic carbon(TOC).Herein,we introduce a new approach to reduce the TOC using the surface silanized nanoparticles,in which the magnetic nanoparticles(mNPs)are silanized and then complexed with ion exchange resin(IER)*** Fe3O4 mNPs are surface modified by using high concentrated vinyltrimethoxysilane(VTMS)and then adhered on the surface of IER *** surface modified mNPs have a thick-shell of polysiloxane layer varying from 5 to 22 nm depending on the amount of VTMS used,which leads the significant increase of specific surface *** IER beads embedding VTMS-silanized mNPs achieves about 7μg/L of the TOC level in ultrapure water system,which is two orders less than 228μg/L of the feeding water and one order less than 96μg/L from the system using pristine IER *** result is mainly attributed to the polysiloxane layer forming broccoli-like surface structure and some part by the vinyl group of VTMS exposed to the amines in the water.

关键词： Total organic carbon Ultrapure water Magnetic nanoparticle Ion-exchange resin Hybrid structure

Continuous Tracking of GPS Signals with Data Wipe-Off Method

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Computers, Materials & Continua 2022年第5期71卷 3803-3820页

作者： Dah-Jing Jwo Kun-chan lee Department of Communications Navigation and Control EngineeringTaiwan Ocean UniversityKeelung202301Taiwan

The decentralized pre-filter based vector tracking loop(VTL)configuration with data wipe-off(DWO)method of the Global Positioning System(GPS)receiver is proposed for performance *** is a challenging task to continuously track the satellites’signals in weak signal environment for the GPS *** is a very attractive technique as it can provide tracking capability in signal-challenged *** the VTL,each channel will not form a loop *** the contrary,the signals in the channels of VTL are shared with each other;the navigation processor in turn predicts the code ***,the receiver can successfully track signals even the signal strength from individual satellite is *** tracking loop based on the pre-filter provides more flexible adjustment to specific environments to reduce noise ***,even if the signals from some satellites are very weak the receiver can track them from the navigation results based on the other *** navigation data,which contains information necessary to perform navigation computations,are binary phase-shift keying(BPSK)modulated onto the GPS carrier phase with the bit duration of 20 ms(i.e.,50 bits per second)for the GPS L1 C/A *** coherent integration interval can be extended for improved tracking performance in signal-challenged ***,tracking accuracy is decreased by possible data bit sign *** DWO algorithm can be employed to remove the data bit in I and Q correlation values so as to avoid energy loss due to bit transitions when the integration interval of the correlator is extended over 20 ms under the low carrier-to-noise ratio(C/No)*** proposed method has an advantage to provide continuous tracking of signals and obtain improved navigation *** evaluation of the tracking capability as well as positioning accuracy will be presented.

关键词： Global positioning system(GPS) vector tracking loop pre-filter data wipe-off weak signal

Improved Dual-image Quality with Reversible Data Hiding Using Translocation and Switching Strategy

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Computer Systems Science & Engineering 2023年第2期44卷 1551-1566页

作者： Chin-Feng lee Kuo-Chung chan Department of Information Management Chaoyang University of TechnologyTaichung41349Taiwan

Dual-image reversible data hiding(RDH)is a technique for hiding important *** technology can be used to safely deliver secret mes-sages to the recipient through dual images in an open network without being easily *** recipient of the image must receive the two stego-images before the secret message can be completely *** is one of the main advantages of data hiding technology;to increase the imperceptibility,the quality requirements of the stego-images are relatively important.A dual ste-ganographic image RDH method,called a DS-CF scheme that can achieve a bet-ter steganographic image quality using the center folding(CF)*** this paper,we developed a translocation and switching strategy(TaS)to shorten the distances between the stego-pixel coordinates and the cover pixel coordinates after information being *** with the DS-CF scheme,our proposed DS-TaS scheme can effectively improve the quality of the steganographic images at the same level of embedding *** experimental results show that the PSNR of our DS-TaS scheme at k=1 was 55.66 dB,which is an increase of 1.5 dB,and is 51.43 dB for k=2,46.66 dB for k=3,and 40.91 dB for k=*** addition,the PSNR values of the stego images was increased by 1.5,0.29,0.29,and 0.19 dB,*** shows that our proposed dual-image RDH method can optimize the visual quality of the stego-images and is better than many other dual-image RDH techniques.

关键词： Information hiding reversible data hiding(RDH) dual-image RDH center folding(CF)strategy

Multiplexed DNA-functionalized graphene sensor with artificial intelligence-based discrimination performance for analyzing chemical vapor compositions

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Microsystems & Nanoengineering 2023年第2期9卷 113-125页

作者： Yun Ji Hwang Heejin Yu Gilho lee Iman Shackery Jin Seong Youngmo jung Seung-Hyun Sung Jongeun Choi Seong chan Jun School of Mechanical Engineering Yonsei University500Yonsei-roSeodaemun-guSeoul 03722Republic of Korea

This study presents a new technology that can detect and discriminate individual chemical vapors to determine the chemical vapor composition of mixed chemical composition in situ based on a multiplexed DNA-functionalized graphene(MDFG)nanoelectrode without the need to condense the original vapor or target *** the best of our knowledge,our artificial intelligence(Al)-operated arrayed electrodes were capable of identifying the compositions of mixed chemical gases with a mixed ratio in the early *** innovative technology comprised an optimized combination of nanodeposited arrayed electrodes and artificial intelligence techniques with advanced sensing capabilities that could operate within biological limits,resulting in the verification of mixed vapor chemical *** selective sensors that are tolerant to high humidity levels provide a target for"breath chemovapor fingerprinting"for the early diagnosis of *** feature selection analysis achieved recognition rates of 99%and above under low-humidity conditions and 98%and above under humid conditions for mixed chemical *** 1D convolutional neural network analysis performed better,discriminating the compositional state of chemical vapor under low-and high-humidity conditions almost *** study provides a basis for the use of a multiplexed DNA-functionalized graphene gas sensor array and artificial intelligence-based discrimination of chemical vapor compositions in breath analysis applications.

关键词： humidity functional intelligence