检索结果-南通市图书馆

Improved Hybrid Beamforming for mmWave Multi-User Massive MIMO

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2021年第6期67卷 3057-3070页

作者： Ji-Sung Jung Won-Seok lee yeong-rong lee Jaeho Kim Hyoung-Kyu Song Department of Information and Communication Engineering and Convergence Engineering for Intelligent Drone Sejong UniversitySeoul05006Korea Department of Electrical Engineering Sejong UniversitySeoul05006Korea

Massive multiple input multiple output(MIMO)has become essential for the increase of capacity as the millimeter-wave(mmWave)communication is ***,hybrid beamforming systems have been studied since full-digital beamforming is impractical due to high cost and power consumption of the radio frequency(RF)*** paper proposes a hybrid beamforming scheme to improve the spectral efciency for multi-user MIMO(MU-MIMO)*** a frequency selective fading environment,hybrid beamforming schemes suffer from performance degradation since the analog precoder performs the same precoding for all *** mitigate performance degradation,this paper uses the average channel covariance matrix for all subcarriers and considers an iterative algorithm to design analog precoder using approximation *** analog precoder is iteratively updated for each column until it *** proposed scheme can reduce errors in the approximating process of the overall spectral *** scheme can be applied to fully-connected and partially-connected *** simulation results show that spectral efciency performance for the proposed scheme is better than the conventional *** proposed scheme can achieve similar performance with full-digital beamforming by using a sufciently large number of RF ***,this paper shows that the proposed scheme outperforms other schemes in the frequency selective fading *** performance improvement can be achieved in both structures.

关键词： Hybrid precoding massive MIMO MU-MIMO mmwave frequency selective fading

Efficacy of chemotherapy containing bevacizumab in patients with metastatic colorectal cancer according to programmed cell death ligand 1

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第8期16卷 3521-3528页

作者： Shin Woo Kang Sung Hee Lim Min-Ji Kim Jeeyun lee Young Suk Park Ho yeong Lim Won Ki Kang Seung Tae Kim Division of Hematology Oncology Department of MedicineSamsung Medical CenterSungkyunkwan University School of MedicineSeoul 06351South Korea Samsung Biomedical Research Institute Samsung Medical CenterSeoul 06351South Korea

BACKGROUND Bevacizumab,an anti-vascular endothelial growth factor(VEGF)monoclonal antibody,inhibits angiogenesis and reduces tumor *** VEGF-C,lactate dehydrogenase,and inflammatory markers have been reported as predictive markers related to bevacizumab *** cell death ligand 1(PD-L1)could act upon VEGF receptor 2 to induce cancer cell angiogenesis and *** To investigate the efficacy of bevacizumab-containing chemotherapy in patients with metastatic colorectal cancer(CRC)according to the expression of *** This analysis included CRC patients who received bevacizumab plus FOLFOX or FOLFIRI as first-line therapy between June 24,2014 and February 28,2022,at Samsung Medical Center(Seoul,South Korea).Analysis of patient data included evaluation of PD-L1 expression by the combined positive score(CPS).We analyzed the efficacy of bevacizumab according to PD-L1 expression status in patients with *** A total of 124 patients was included in this *** all patients were treated with bevacizumab plus FOLFIRI or FOLFOX as the first-line *** 77%of patients received FOLFOX,23%received FOLFIRI as backbone first-line *** numbers of patients with a PD-L1 CPS of 1 or more,5 or more,or 10 or more were 105(85%),64(52%),and 32(26%),*** results showed no significant difference in progression-free survival(PFS)and overall survival(OS)with bevacizumab treatment between patients with PDL1 CPS less than 1 and those with PD-L1 CPS of 1 or more(PD-L1<1%vs PD-L1≥1%;PFS:P=0.93,OS:P=0.33),between patients with PD-L1 CPS less than 5 and of 5 or more(PD-L1<5%vs PD-L1≥5%;PFS:P=0.409,OS:P=0.746),and between patients with PD-L1 CPS less than 10 and of 10 or more(PD-L1<10%vs PD-L1≥10%;PFS:P=0.529,OS:P=0.568).CONCLUSION Chemotherapy containing bevacizumab can be considered as first-line therapy in metastatic CRC irrespective of PD-L1 expression.

关键词： Bevacizumab Colorectal cancer Programmed cell death ligand 1 expression First-line chemotherapy Metastatic colorectal cancer

Trends in colorectal cancer incidence according to an increase in the number of colonoscopy cases in Korea

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第1期16卷 51-60页

作者： Ga Hee Kim yeong Chan lee Tae Jun Kim Sung Noh Hong Dong Kyung Chang Young-Ho Kim Dong-Hoon Yang Chang Mo Moon Kyunga Kim Hyun Gun Kim Eun-Ran Kim Division of Gastroenterology Department of Internal MedicineAsan Medical CenterUniversity of Ulsan College of MedicineSeoul 05505South Korea Department of Digital Health Samsung Advanced Institute for Health Science and TechnologySungkyunkwan University School of MedicineSeoul 06351South Korea Division of Gastroenterology Department of Internal MedicineSamsung Medical CenterSungkyunkwan University School of MedicineSeoul 06351South Korea Division of Gastroenterology Department of Internal MedicineEwha Womans UniversitySeoul 07985South Korea Biomedical Statistics Center Samsung Medical CenterSeoul 06351South Korea Division of Gastroenterology Department of Internal MedicineSoonchunhyang University College of MedicineSeoul 04401South Korea

BACKGROUND The incidence of colorectal cancer(CRC)and preinvasive CRC(e.g.,early colon cancer and advanced adenoma)is gradually increasing in several *** To evaluate the trend in incidence of CRC and preinvasive CRC according to the increase in the number of colonoscopies performed in *** This retrospective cohort study enrolled Korean patients from 2002 to 2020 to evaluate the incidence of CRC and preinvasive CRC,and assess the numbers of diagnostic colonoscopies and colonoscopic ***-related complications by age group were also *** The incidence of CRC showed a rapid increase,then decreased after 2012 in the 50-75 year-age *** the study period,the rate of incidence of preinvasive CRC increased at a similar level in patients under 50 and 50-75 years of *** 2009,the increase has been rapid,showing a pattern similar to the increase in *** rate of colonoscopic polypectomy in patients aged under 50 was similar to the rate in patients over 75 years of age after *** rate of complications after colonoscopy and related deaths within 3 mo was high for those over 75 years of *** The diagnosis of preinvasive CRC increased with the increase in the number of colonoscopies *** the risk of colonoscopy-related hospitalization and death is high in the elderly,if early lesions at risk of developing CRC are diagnosed and treated under or at the age of 75,colonoscopy-related complications can be reduced for those aged 76 years or over.

关键词： Colorectal cancer Preinvasive colorectal cancer Colorectal polypectomy Colonoscopy

Enhancing Identity Protection in Metaverse-Based Psychological Counseling System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第1期78卷 617-632页

作者： Jun lee Hanna lee Seong Chan lee Hyun Kwon Department of Game Software Hoseo UniversityAsan-si31499Korea Yatav Enter Seoul04799Korea Department of Artificial Intelligence and Data Science Korea Military AcademySeoul01805Korea

Non-face-to-face psychological counseling systems rely on network technologies to anonymize information regard-ing client ***,these systems often face challenges concerning voice data leaks and the suboptimal communication of the client’s non-verbal expressions,such as facial cues,to the *** study proposes a metaverse-based psychological counseling system designed to enhance client identity protection while ensuring efficient information delivery to counselors during non-face-to-face *** proposed systemincorporates a voicemodulation function that instantlymodifies/masks the client’s voice to safeguard their ***,it employs real-time client facial expression recognition using an ensemble of decision trees to mirror the client’s non-verbal expressions through their avatar in the metaverse *** system is adaptable for use on personal computers and smartphones,offering users the flexibility to access metaverse-based psychological counseling across diverse *** performance evaluation of the proposed system confirmed that the voice modulation and real-time facial expression replication consistently achieve an average speed of 48.32 frames per second or higher,even when tested on the least powerful smartphone ***,a total of 550 actual psychological counseling sessions were conducted,and the average satisfaction rating reached 4.46 on a 5-point *** indicates that clients experienced improved identity protection compared to conventional non-face-to-face metaverse counseling ***,the counselor successfully addressed the challenge of conveying non-verbal cues from clients who typically struggled with non-face-to-face psychological *** proposed systemholds significant potential for applications in interactive discussions and educational activities in the metaverse.

关键词： Metaverse counseling system face tracking identity protection

Pyrometallurgical recycling of end-of-life lithium-ion batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1554-1571页

作者： Juheon lee Kwang Won Park Il Sohn Sanghoon lee Department of Materials Science and Engineering Seoul 03722Korea Yonsei Industry Cooperation Center Yonsei UniversitySeoul 03722Korea RD Solution Wanju gunJeollabuk do 55365Korea

The global importance of lithium-ion batteries(LIBs)has been increasingly underscored with the advancement of high-performance energy storage ***,the end-of-life of these batteries poses significant challenges from environmental,economic,and resource management *** review paper focuses on the pyrometallurgy-based recycling process of lithium-ion batteries,exploring the fundamental understanding of this process and the importance of its *** on the high energy consumption and emission gas issues of the pyrometallurgical recycling process,we systematically analyzed the capital-intensive nature of this process and the resulting technological ***,we conducted an in-depth discussion on the future research directions to overcome the existing technological barriers and *** review will provide valuable insights for researchers and industry stakeholders in the battery recycling field.

关键词： spent lithium-ion batteries recycling sustainability lithium valuable metal

Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 819-836页

作者： D.lee S.CHANG J.lee Department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea School of Mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea Department of Mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random *** method consists of a generalized polynomial chaos expansion(GPCE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data *** the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to random *** allows for avoiding repeated computations of invariant substructures while generating the input-output data *** substructuring with static condensation further improves the computational efficiency of the reanalysis without losing ***,the GPCE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional *** numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPCE using full finite element analyses(FEAs).We also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)random inputs.

关键词： forward uncertainty quantification(UQ) generalized polynomial chaos expansion(GPCE) static reanalysis method static condensation substructuring

Regulating interfacial stability of SiO_(x) anode with fluoride-abundant solid–electrolyte interphase by fluorine-functionalized additive

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第2期43卷 671-681页

作者： Subin lee Taeeun Yim Advanced Batteries Laboratory Department of ChemistryIncheon National UniversityIncheon22012Republic of Korea Research Institute of Basic Sciences College of Natural ScienceIncheon National UniversityIncheon22012Republic of Korea

Silicon oxide(SiO_(x))has received remarkable attention as a next-generation battery material;however,the sudden decrease in the cycling retention constitutes a significant challenge in facilitating its ***(2,2,2-trifluoroethyl)phosphite(TTFP),which can control parasitic reactions such as the pulverization of SiO_(x)anode materials and electrolyte decomposition,has been proposed to improve the lifespan of the *** electrochemical reduction of TTFP results in solid-electrolyte interphase(SEI)layers that are mainly composed of LiF,which occur at a higher potential than the working potential of the SiO_(x)anode and carbonate-based *** electrolyte with TTFP exhibited a substantial improvement in cycling retention after 100 cycles,whereas the standard electrolyte showed acutely decreased *** thickness of the SiO_(x)anode with TTFP also changed only slightly without any considerable delamination spots,whereas the SiO_(x)anode without TTFP was prominently deformed by an enormous volume expansion with several internal *** cycled SiO_(x)anode with TTFP exhibited less increase in resistance after cycling than that in the absence of TTFP,in addition to fewer decomposition adducts in corresponding X-ray photoelectron spectroscopy(XPS)analyses between the cycled SiO_(x)*** results demonstrate that TTFP formed SEI layers at the SiO_(x)interface,which substantially reduced the pulverization of the SiO_(x)anode materials;in addition,electrolyte decomposition at the interface decreased,which led to improved cycling retention.

关键词： Lithium-ion batteries(LIBs) Silicon oxide anode Electrolyte Additive Solid-electrolyte interphases(SEI) Tris(2,2,2-trifluoroethyl)phosphite

Block Incremental Dense Tucker Decomposition with Application to Spatial and Temporal Analysis of Air Quality Data

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第4期139卷 319-336页

作者： SangSeok lee HaeWon Moon lee Sael Department of Artificial Intelligence Ajou UniversitySuwon-si16499Korea Department of Software and Computer Engineering Ajou UniversitySuwon-si16499Korea

How can we efficiently store and mine dynamically generated dense tensors for modeling the behavior of multidimensional dynamic data?Much of the multidimensional dynamic data in the real world is generated in the form of time-growing *** example,air quality tensor data consists of multiple sensory values gathered from wide locations for a long *** data,accumulated over time,is redundant and consumes a lot ofmemory in its raw *** need a way to efficiently store dynamically generated tensor data that increase over time and to model their behavior on demand between arbitrary time *** this end,we propose a Block IncrementalDense Tucker Decomposition(BID-Tucker)method for efficient storage and on-demand modeling ofmultidimensional spatiotemporal *** that tensors come in unit blocks where only the time domain changes,our proposed BID-Tucker first slices the blocks into matrices and decomposes them via singular value decomposition(SVD).The SVDs of the time×space sliced matrices are stored instead of the raw tensor blocks to save *** modeling from data is required at particular time blocks,the SVDs of corresponding time blocks are retrieved and incremented to be used for Tucker *** factor matrices and core tensor of the decomposed results can then be used for further data *** compared our proposed BID-Tucker with D-Tucker,which our method extends,and vanilla Tucker *** show that our BID-Tucker is faster than both D-Tucker and vanilla Tucker decomposition and uses less memory for storage with a comparable reconstruction *** applied our proposed BID-Tucker to model the spatial and temporal trends of air quality data collected in South Korea from 2018 to *** were able to model the spatial and temporal air quality *** were also able to verify unusual events,such as chronic ozone alerts and large fire events.

关键词： Dynamic decomposition tucker tensor tensor factorization spatiotemporal data tensor analysis air quality

The association between C-reactive protein to albumin ratio and 6-month neurological outcome in patients with in-hospital cardiac arrest

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Emergency Medicine 2024年第3期15卷 223-228页

作者： Ji Ho lee Dong Hun lee Byung Kook lee Seok Jin Ryu Department of Emergency Medicine Chonnam National University HospitalGwangju 61469Republic of Korea Department of Emergency Medicine Chonnam National University Medical SchoolGwangju 61469Republic of Korea

The global incidence rates of in-hospital cardiac arrest(IHCA)range from1.2 to 9.0 per1,000 hospitalized patients,as per the National Cardiac Arrest Database.[1] While IHCAs tend to exhibit superior 30-day survival rates relative to out-of-hospital cardiac arrests (OHCA) due to situational advantages,such as immediate access to medical personnel and treatments.

关键词： patients cardiac IHC