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Modeling of air quality with a modified two-dimensional Eulerian model: A case study in the Pearl River Delta (PRD) region of China

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Journal of Environmental Sciences 2007年第5期19卷 572-577页

作者： CHENG Yan-li BAI Yu-hua li jin-long liu Zhao-rong College of Environmental Sciences Peking University Beijing 100871 China

A modified two-dimensional Eulerian air quality model was used to simulate both the gaseous and particulate pollutant concentrations during October 21-24, 2004 in the Pearl River Delta （PRD） region, China. The most significant improvement to the model is the added capability to predict the secondary organic aerosols （SOA） concentrations because of the inclusion of the SOA formation chemistry. The meteorological input data were prepared using the CALMET meteorological model. The concentrations of aerosol-bound species such as NO3^-, NH4^＋, SO4^2-, and SOA were calculated in the fine particle size range （〈2.5 μm）. The results of the two-dimensional model were compared to the measurements at the ground level during the PRD Intensive Monitoring Campaign （IMC）. Overall, there were good agreements between the measured and modeled concentrations of inorganic aerosol components and O3. Both the measured and the modeled results indicated that the maximum hourly O3 concentrations exceeded the China National Air Quality Standard. The predicted 24-h average SOA concentrations were in reasonable agreement with those predicted by the method of minimum OC/EC ratio.

关键词： air quality model numerical simulation secondary organic aerosol inorganic aerosol

Photon-Induced Production of Mirror Quarks from LHT Model at LHC

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Communications in Theoretical Physics 2009年第12期52卷 1041-1048页

作者： YUE Chong-Xing liu jin-Yan DING li liu Wei MA Wei Department of Physics Liaoning Normal University Dalian 116029 China

The photon-induced processes at the LHC provide clean experimental conditions due to absence of theproton remnants,which might produce complementary and interesting results for tests of the standard model and forsearching of new *** the context of the littlest Higgs model with T-parity,we consider the photon-inducedproduction of the mirror quarks at the *** cross sections for various production channels are calculated and asimply phenomenological analysis is performed by assuming leptonic decays.

关键词： the mirror fermions the LHT model the LHC

Localization−delocalization transitions in non-Hermitian Aharonov−Bohm cages

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Frontiers of physics 2024年第3期19卷 39-50页

作者： Xiang li jin liu Tao liu School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

A unique feature of non-Hermitian systems is the extreme sensitivity of the eigenspectrum to boundary conditions with the emergence of the non-Hermitian skin effect (NHSE). A NHSE originates from the point-gap topology of complex eigenspectrum, where an extensive number of eigenstates are anomalously localized at the boundary driven by nonreciprocal dissipation. Two different approaches to create localization are disorder and flat-band spectrum, and their interplay can lead to the anomalous inverse Anderson localization, where the Bernoulli anti-symmetric disorder induces mobility in a full-flat band system in the presence of Aharonov−Bohm (AB) Cage. In this work, we study the localization−delocalization transitions due to the interplay of the point-gap topology, flat band and correlated disorder in the one-dimensional rhombic lattice, where both its Hermitian and non-Hermitian structures show AB cage in the presence of magnetic flux. Although it remains the coexistence of localization and delocalization for the Hermitian rhombic lattice in the presence of the random anti-symmetric disorder, it surprisingly becomes complete delocalization, accompanied by the emergence of NHSE. To further study the effects from the Bernoulli anti-symmetric disorder, we found the similar NHSE due to the interplay of the point-gap topology, correlated disorder and flat bands. Our anomalous localization−delocalization property can be experimentally tested in the classical physical platform, such as electrical circuit.

关键词： non-Hermitian skin effects disorder flat band localization−delocalization transition

Adaptive Bistable Stochastic Resonance Based Weak Signal Reception in Additive Laplacian Noise

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China Communications 2024年第1期21卷 228-241页

作者： jin liu Zan li Qiguang Miao li Yang School of Computer Science and Technology Xidian UniversityXi’an 710071China State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China

Weak signal reception is a very important and challenging problem for communication systems especially in the presence of non-Gaussian noise,and in which case the performance of optimal linear correlated receiver degrades *** at this,a novel uncorrelated reception scheme based on adaptive bistable stochastic resonance(ABSR)for a weak signal in additive Laplacian noise is *** analyzing the key issue that the quantitative cooperative resonance matching relationship between the characteristics of the noisy signal and the nonlinear bistable system,an analytical expression of the bistable system parameters is *** this basis,by means of bistable system parameters self-adaptive adjustment,the counterintuitive stochastic resonance(SR)phenomenon can be easily generated at which the random noise is changed into a benefit to assist signal ***,it is demonstrated that approximately 8dB bit error ratio(BER)performance improvement for the ABSR-based uncorrelated receiver when compared with the traditional uncorrelated receiver at low signal to noise ratio(SNR)conditions varying from-30dB to-5dB.

关键词： adaptive bistable stochastic resonance additive Laplacian noise low signal to noise ratio uncorrelated reception scheme weak signal reception

Incombustible solid polymer electrolytes:A critical review and perspective

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Journal of Energy Chemistry 2024年第6期93卷 264-281,I0007页

作者： Kai Wu jin Tan Zhenfang liu Chenguang Bao Ao li Qi liu Baohua li College of Materials Science and Engineering Hunan UniversityChangsha 413000HunanChina Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 055GuangdongChina

Since the advent of the solid-state batteries,employing solid polymer electrolytes(SPEs)to replace routine flammable liquid electrolytes is regarded to be one of the most promising solutions in pursing highenergy-density battery *** with superior thermal stability,good processability,and high mechanical modulus obtain increasing ***,SPE-based batteries are not impenetrable due to their decomposition and combustibility under extreme *** believe incorporating appropriate flame-retardant additives/solvents/fragments into SPEs can intrinsically reduce their flammability to solve the battery safety *** this review,the recent research progress of incombustible SPEs,with special emphasis on flame-retardant structural design,is ***,a brief introduction of flame-retardant mechanism,evaluation index for safety of SPEs,and a detailed overview of the latest advances on diverse-types SPEs in various battery systems are *** deep insight into thermal ru naway process,the free-standing incombustible GPEs,and the ratio nal design of pouch cell structures may be the main directions to motivate revolutionary next-generation for safety batteries.

关键词： Non-flammable electrolyte Solid polymer electrolyte High safety electrolyte Solid state electrolyte Solid state battery

A novel interpretable multilevel wavelet decomposition deep network for actual heartbeat classification

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Science China(Technological Sciences) 2024年第6期67卷 1842-1854页

作者： jin YanRui li ZhiYuan TIAN YuanYuan WEI XiaoYang liu Chengliang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China

Arrhythmias may lead to sudden cardiac death if not detected and treated in time.A supraventricular premature beat(SPB)and premature ventricular contraction(PVC)are important categories of arrhythmia ***,deep learning methods have been applied to the PVC/SPB heartbeats ***,most researchers have focused on time-domain information of the electrocardiogram and there has been a lack of exploration of the interpretability of the *** this study,we design an interpretable and accurate PVC/SPB recognition algorithm,called the interpretable multilevel wavelet decomposition deep network(IMWDDN).Wavelet decomposition is introduced into the deep network and the squeeze and excitation(SE)-Residual block is designed for extracting time-domain and frequency-domain ***,inspired by the idea of residual learning,we construct a novel loss function for the constant updating of the multilevel wavelet decomposition ***,the IMWDDN is evaluated on the Third China Physiological Signal Challenge Dataset and the MIT-BIH Arrhythmia *** comparison results show IMWDDN has better detection performance with 98.51%accuracy and a 93.75%F1-macro on average,and its areas of concern are similar to those of an expert diagnosis to a certain ***,the IMWDDN has good application value in the clinical screening of PVC/SPB heartbeats.

关键词： actual heartbeat classification electrocardiogram interpretable deep network multilevel discrete wavelet decomposition layer SE-Residual block

A novel lightweight computerized ECG interpretation approach based on clinical 12-lead data

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Science China(Technological Sciences) 2024年第2期67卷 449-463页

作者： liu YunQing QIN Chengjin liu jinLei jin YanRui li ZhiYuan ZHAO liQun liu Chengliang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Key Labof Artificial Intelligence(Ministryof Education) AI InstituteShanghai Jiao Tong UniversityShanghai 200240China Department of Cardiology Shanghai First Peoples Hospital Affiliated to Shanghai Jiao Tong UniversityShanghai 200080China

Although 12-lead electrocardiograms(ECGs)provide a wide range of spatiotemporal characteristics,interpreting them for arrhythmia detection is difficult due to a lack of reliable large-scale clinical ***,we proposed an innovative lightweight computerized ECG interpretation approach based on 12-lead *** model was trained,validated,and tested on 53845 standard 12-lead ECG records collected at Shanghai First People’s Hospital in affiliation with Shanghai Jiao Tong *** experiments revealed that our approach had a classification accuracy of 94.41%in the classification task of seven types of rhythms,which was markedly superior to related single-lead and 12-lead ECG classification ***,the average receiver operating characteristic area under the curve reached a value of 0.940,and the precision values for sinus tachycardia and sinus bradycardia were 0.945 and 0.91,respectively,with specificity values of 0.996 and *** employing our boosting method,we were able to improve the accuracy to 94.85%.To investigate the performance degradation of the proposed neural network in some classes,an ECG cardiologist was enlisted to review questionable ECGs;this process provides a promising direction for network performance ***,the proposed computerized ECG interpretation approach has practical significance because it could help professional physicians analyze patients’heart conditions based on real-time 12-lead ECG or grade their disease severity in advance.

关键词： computerized ECG interpretation large-scale 12-lead clinical ECG database lightweight neural network

Experimental realization of deterministic joint remote preparation of an arbitrary two-qubit pure state via GHZ states

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Science China(Information Sciences) 2024年第3期67卷 317-318页

作者： Nachuan li Lu XU jin-Ming liu State Key Laboratory of Precision Spectroscopy School of Physics and Electronic ScienceEast China Normal University Hefei Origin Quantum Computing Technology Co. Ltd.

Quantum teleportation(QT) [1] enables secure transfer of an unknown quantum state between remote locations without physically transmitting the initial state. Unlike QT,with the sender possessing complete knowledge of the initial state, remote state preparation(RSP) [2] exhibits a tradeoff between the amount of the entanglement resource used and the classical communication cost.

关键词： Quantum communication

Carotid endarterectomy for ameliorating the symptoms of transient ischemic attack A six-month postoperative follow-up

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Neural Regeneration Research 2007年第12期2卷 764-768页

作者： Chenxi Ouyang Bi jin Yiqing li Jianyong liu Weici Wang Department of Vascular Surgery Union Hospital Affiliated to Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 Hubei Province China

BACKGROUND： Carotid endarterectomy has certain risks, but it has obvious effects on preventing the occurrence of stroke. OBJECTIVE： To identify the effects of carotid endarterectomy on ameliorating the clinical symptoms and physical signs of patients with cerebral ischemia. DESIGN： A follow-up study. SETTING： Union Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology. PARTICIPANTS： Sixteen patients with carotid atherosclerotic stenosis accompanied by ischemic symptoms were selected from the Department of Vascular Surgery, Union Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology from March 2005 to May 2007. There were 11 males and 5 females, aged from 40 to 81 years old with a mean age of 60 years old, and they were all clearly diagnosed by carotid color Doppler ultrasound. Informed consent was obtained from all the patients. The study was approved by the hospital ethical committee. METHODS：（1） All the 16 patients were performed with unilateral stripping of arteriosclerotic plaque and Carotid endarterectomy, and 6 of them with bilateral stenosis was operated on the side with more serious stenosis. （2） The clinical symptoms, physical signs before and after operation, and the operative complications were observed. （3） The patients were followed up for 6 months postoperatively. The smoothness of carotid arteries was detected with color Doppler ultrasound. The degrees of satisfaction to the quality of living were evaluated. MAIN OUTCOME MEASURES：（1） Amelioration of clinical symptoms postoperatively; （2） Smoothness of carotid arteries postoperatively; （3） Degrees of satisfaction to the quality of living; （4） Postoperative complications. RESULTS： All the 16 patients were involved in the final analysis of results. （1） Amelioration of clinical symptoms and physical signs： The postoperative muscle strengths of 3 patients with stroke history were significantly ameliorated; For the

关键词： carotid endarterectomy cerebral ischemia stroke