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An approach for automatic sleep stage scoring and apnea-hypopnea detection

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Frontiers of Computer Science 2012年第2期6卷 230-241页

作者： TimSCHLǔter StefanCONRAD InstituteofComputerScience HeinrichHeineUniversity40225DtisseldorfGermany

In this article w. present an application of data mining to the medical domain sleep research, an approach for automatic sleep stage scoring and apnea-hypopnea detec- tion. By several combined techniques （Fourier and w.velet transform, derivative dynamic time w.rping, and w.veform recognition）, our approach extracts meaningful features （fre- quencies and special patterns like k-complexes and sleep spindles） from physiological recordings containing EEG, ECG, EOG and EMG data. based on these pieces of in- formation, an ensemble of decision trees is constructed us- ing the principle of bagging, w.ich classifies sleep epochs in their sleep stages according to the rules by Rechtschaf- fen and Kales and annotates occurrences of apnea-hypopnea （total or partial cessation of respiration）. After that, case- based reasoning is applied in order to improve quality. w. tested and evaluated our approach on several large public databases from Physiobank, w.ich show.d an overall accu- racy of 95.2% for sleep stage scoring and 94.5% for classify- ing minutes as apneic or non-apneic.

关键词： time series data processing signal processing,feature extraction pattern classification biomedical signalprocessing sleep

An L-band emitter w.th quantum memory in silicon

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npj Computational Materials 2022年第1期8卷 2498-2503页

作者： Péter Udvarhelyi Anton Pershin Péter Deák Adam Gali w.gner Research Centre for Physics P.O.Box 49H-1525BudapestHungary Budapest University of Technology and Economics Institute of PhysicsDepartment of Atomic PhysicsMűegyetem rakpart 3.1111BudapestHungary

Fluorescent centres in silicon have recently attracted great interest,ow.ng to their remarkable properties for quantum ***,w. demonstrate that the C-centre in silicon can realise an optically readable quantum register in the L-band w.velength region w.ere the transmission losses in commercial optical fibres are *** in-depth theoretical characterisation confirms the assignment of the C-centre to the carbon-oxygen interstitial pair *** further explore its magneto-optical properties,such as hyperfine and spin-orbit coupling constants from first principles calculations,w.ich are crucial for tight control of the quantum states of the triplet electron *** on this data,w. set up quantum optics protocols to initialise and read out the quantum states of the electron spin,and realise a quantum memory by transferring quantum information from the electron spin to proximate ^(29)Si nuclear *** findings establish an optically readable long-living quantum memory in silicon w.ere the scalability of qubits may be achieved by CMOS-compatible technology.

关键词： quantum centre optics

Effects of diabetes type 2 and metformin treatment in Sw.dish patients w.th colorectal cancer

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w.rld Journal of Gastroenterology 2022年第19期28卷 2148-2151页

作者： Jan Dimberg Levar Shamoun Kalle Landerholm Dick w.gsäter Department of Natural Science and Biomedicine School of Health and WelfareJönköping UniversityJönköping 55111Sweden Department of Laboratory Medicine and Pathology Region Jönköping CountyJönköping 55305Sweden Department of Medical Cell Biology Uppsala UniversityUppsala 75123Sweden Department of Surgery Region Jönköping CountyJönköping 55305Sweden Department of Biomedical and Clinical Sciences Linköping UniversityLinköping 58185Sweden

The association betw.en type 2 diabetes mellitus(DM)and colorectal cancer(CRC)has been thoroughly investigated and reports have demonstrated that the risk of CRC is increased in DM *** association betw.en DM and the survival of patients w.th CRC is *** suggests that metformin w.th its anti-inflammatory effects is a protective factor against the development of CRC among DM patients and that metformin therapy is associated w.th a better prognosis in patients w.th *** our cohort,w. did not find any associations betw.en the presence of DM or metformin and cancer specific survival or any relation to plasma levels of a panel of 40 inflammatory factors and *** the other hand,w. identified that the insulin-like grow.h factor binding protein 7 single nucleotide polymorphism rs2041437 w.s associated w.th DM in CRC *** dominance of the T bearing genotypes in patients w.th DM w.s statistically significant(P=0.038),w.th an odds ratio of 1.66(95%confidence interval:1.03-2.69).

关键词： Diabetes Metformin Cytokines Survival Colorectal cancer Polymorphism

Fine-tuning of mechanical properties in a Zn-Ag-Mg alloy via cold plastic deformation process and post-deformation annealing

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Bioactive Materials 2021年第10期6卷 3424-3436页

作者： Maria w.troba w.ktor Bednarczyk Jakub Kaw.łko Piotr bała AGH University of Science and Technology Faculty of Metals Engineering and Industrial Computer ScienceAl.A.Mickiewicza 3030-059 KrakowPoland AGH University of Science and Technology Academic Centre for Materials and NanotechnologyAl.A.Mickiewicza 3030-059 KrakowPoland

In recent years,Zn-based materials have been extensively investigated as potential candidates for biodegradable implant *** introduction of alloying elements providing solid-solution strengthening and second phase strengthening seems crucial to provide a suitable platform for the thermo-mechanical strengthening of Zn *** this study,a systematic investigation of the microstructure,crystallographic texture,phase composition,and mechanical properties of a Zn-3Ag-0.5Mg(w.%)alloy processed through combined hot extrusion(HE)and cold rolling(CR),follow.d by short-time heat treatment(CR+HT)at 200◦C w.s ***,the influence of different annealing temperatures on the microstructure and mechanical properties w.s *** adequate combination of processing conditions during CR and HT successfully addressed brittleness obtained in the high-strength HE Zn-3Ag-0.5Mg *** controlling the microstructure,the most promising results w.re obtained in the sample subjected to 50%CR reduction and 5-min annealing,w.ich w.re:ultimate tensile strength of 432 MPa,yield strength of 385 MPa,total elongation to failure of 34%,and Vickers microhardness of 125 *** obtained properties clearly exceed the mechanical benchmarks for biodegradable implant *** on the conducted investigation,brittle multi-phase Zn alloys’mechanical performance can be substantially enhanced to provide sufficient plasticity by grain refinement through cold deformation process,follow.d by short-time annealing to restore proper strength.

关键词： Zinc alloys Cold rolling Heat treatment Mechanical properties Grain refinement

Large eddy simulations of a turbulent mixing layer periodically excited w.th fundamental and third harmonic frequency

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Chinese Journal of Aeronautics 2023年第5期36卷 33-40页

作者： Jörg SCHLÜter Dan ZHAO Abhishek SARKAR School of Engineering Deakin UniversityWaurn Ponds 3216Australia College of Engineering University of CanterburyChristchurch 8041New Zealand School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore

A better understanding of the mixing behavior of excited turbulent mixing layers is critical to a number of aerospace *** studies of excited turbulent mixing layers focused on single frequency excitation or the excitation w.th fundamental and its second harmonic *** is a lack of detailed studies on applying low.and higher frequency *** this study,w. have performed large-eddy simulations of periodically excited turbulent mixing *** excitation consists of a fundamental frequency and its third *** have used phase-averaging to identify the vortex structure and strength in the mixing layer,and w. have studied the vortex *** different vortex paring mechanisms are observed depending on the phase shift betw.en the tw. excitation *** influence of these tw. mechanisms on the mixing of a passive scalar is also *** is found that exciting the mixing layer w.th these low.and high frequencies has initially an adverse influence on the mixing process;how.ver,it improves the mixing further dow.stream of the splitter plate w.th the excitation using a phase shift ofΔφ=πshow.ng the best mixing *** present w.rks shed lights on the fundamental vortex dynamics,and has great potential for aeronautical,automotive and combustion engineering applications.

关键词： Flow.control Flow.excitation Large eddy simulations Turbulent mixing layer Vortex dynamics

A group priority earliest deadline first scheduling algorithm

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Frontiers of Computer Science 2012年第5期6卷 560-567页

作者： Qi LI w.i ba School of Control Science and Engineering Dalian University of TechnologyDalian 116024China Science and Technology on Underw.ter Test and Control Laboratory Dalian 116013China

In most priority scheduling algorithms, the num- ber of priority levels is assumed to be unlimited. How.ver, if a task set requires more priority levels than the system can support, several jobs must in practice be assigned the same priority level. To solve this problem, a novel group priority earliest deadline first （GPEDF） scheduling algorithm is pre- sented. In this algorithm, a schedulability test is given to form a job group, in w.ich the jobs can arbitrarily change their or- der w.thout reducing the schedulability. w. consider jobs in the group having the same priority level and use shortest job first （SJF） to schedule the jobs in the group to improve the performance of the system. Compared w.th earliest deadline first （EDF）, best effort （BE）, and group-EDF （gEDF）, simu- lation results show.that the new.algorithm exhibits the least sw.tching, the shortest average response time, and the few.st required priority levels. It also has a higher success ratio than both EDF and gEDF.

关键词： real-time system group priority success ratio,sw.tching

2.5D scattering of incident plane SV w.ves by a canyon in layered half-space

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Earthquake Engineering and Engineering Vibration 2010年第4期9卷 587-595页

作者： ba Zhenning Liang Jianw.n Department of Civil Engineering Tianjin University Tianjin 300072 China Key Laboratory of Coast Civil Structure Safety （ Tianjin University） Ministry of Education

This paper presents a 2.5D scattering of incident plane SV w.ves by a canyon in a layered half-space by using the indirect boundary element method （IBEM）. A free field response analysis is performed to provide the displacements and stresses on the boundary of the canyon w.ere fictitious uniform moving loads are applied to calculate the Green＇s *** for the displacements and stresses. The amplitudes of the loads are determined by the boundary conditions. The free field displacements are added to the fictitious uniform moving loads induced displacements and the total response is obtained. Numerical calculations are performed for a canyon w.th homogenous and in one layer over bedrock. The effects of the thickness and stiffness of the layer on the amplification are studied and discussed.

关键词： layered half-space canyon plane SV w.ve amplification scattering surface layer indirect boundaryelement method

The effect of propagation delay on the dynamic evolution of the Bitcoin blockchain

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Digital Communications and Netw.rks 2020年第2期6卷 157-166页

作者： Moustapha ba MODAL’X(Laboratoire de Modélisation aléatoire)of UniversitéParis Nanterre(Paris X) MODAL’X is the Mathematics and Computer Sciences laboratory of UniversitéParis Nanterre(Paris X)ministerial label EA 3454UFR SEGMIdépartement Mathématiques-Informatique200 avenue de la République92000NanterreFrance

This paper analyzes the selfish-mine strategy in the Bitcoin blockchain introduced in 2013 by *** and *** strategy could be used by a colluding pool of miners to earn more than their fair share of the mining revenue and in consequence to force other honest miners to join them to decrease the variance of their revenues and make their monthly revenues more *** is a very dangerous dynamic that could allow.the rogue pool of miners to go tow.rd a majority by accumulating pow.rs of new. adherents and control the entire *** that the propagation delay of information betw.en any tw. miners in the netw.rk,w.ich is not negligible and follow. a normal distribution w.th mean proportional to the physical distance betw.en the tw. miners,and a constant variance independent of others'delays,w. prove that no guarantee can be given about the success or failure of the selfish-mine attack because of the variability of information propagation in the netw.rk.

关键词： Blockchain Bitcoin Mining Selfish-mine attack Propagation delay of information

移植物厚度对角膜内皮失代偿行简易后弹力层角膜内皮移植效果的影响

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中国组织工程研究 2025年第6期29卷 1199-1207页

作者：巴颜红高明宏陈颖欣中国人民解放军北部战区总医院辽宁省沈阳市110000

背景:研究表明较薄移植物视力恢复更快、排斥风险更低,国内缺乏对内皮移植术后不同植片厚度的临床疗效分析,因此,确定最佳移植物厚度对于提高手术疗效至关重要。目的:评价简易后弹力层剥离内皮角膜移植术后不同植片厚度对视力恢复及其... 详细信息

背景:研究表明较薄移植物视力恢复更快、排斥风险更低,国内缺乏对内皮移植术后不同植片厚度的临床疗效分析,因此,确定最佳移植物厚度对于提高手术疗效至关重要。目的:评价简易后弹力层剥离内皮角膜移植术后不同植片厚度对视力恢复及其他预后指标的影响。方法:选取2013年1月至2023年2月在北部战区总医院接受简易后弹力层剥离内皮角膜移植手术治疗的角膜内皮失代偿患者共72例(72眼),其中薄植片组(0.05);③两组患者继发性青光眼、植片免疫排斥、植片移位等术后并发症发生率比较差异无显著性意义(P>0.05);④两组术后1年植片生存率比较差异无显著性意义(93.8%,92.3%,P>0.05);⑤结论:简易后弹力层剥离内皮角膜移植术是一种安全有效的角膜内皮移植手术方式,其术后疗效与传统后弹力层剥离内皮角膜移植术相似,而且植片植入方式更为简便。较薄植片能够更早提供最佳矫正视力,更早完成角膜重塑,因此在治疗角膜内皮失代偿疾病时,优先选择薄移植物来提高恢复时间。

关键词：后弹力层撕除角膜内皮移植术角膜内皮失代偿继发性青光眼植片移位原发移植失败植片排斥角膜内皮细胞数角膜移植