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A density functional theoretical studies on the structures and aromaticities of (CH)_n(BCO)_(6-n) (n=0-6)

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Chinese Chemical Letters 2008年第11期19卷 1383-1386页

作者： Zheng Guo Huang Li Zhou en cui yang Chemistry and Life Science College Tianjin Normal University Tianjin 300387 China Department of Chemistry ＆ Chemical engineering Zaozhuang University Zaozhuang 277160 China

Density functional theoretical calculations have been made on the electronic structure of （CH）n（BCO）6-n（n = 0-6） at B3LYP/6- 311 ＋ G（d） level. The nuclear-independent chemical shifts （NICS） values calculated using the gauge-including atomic orbitals （GIAO） method were used to assess on the aromaticities of these molecules. The results shows that （CH）n（BCO）6n（n = 0-6） species are aromatic.

关键词： NICS Aromaticity Density functional theory Boron carbonyl compound

An ab initio potential energy surface and vibrational energy levels of HXeBr

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Chinese Chemical Letters 2008年第5期19卷 627-630页

作者： Zheng Guo Huang en cui yang Dai Qian Xie Chemistry and Life Science College Tianjin Normal UniversityTianjin 300387 China Institute of Theoretical and Computational Chemistry School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

A three-dimensional global potential energy surface for the electronic ground state of HXeBr molecule is constructed from more than 4200 ab initio points. These points are generated using an internally contracted multi-reference configuration interaction method with the Davidson correction （icMRCI ＋ Q） and large basis sets. The stabilities and dissociation barriers are identified from the potential energy surfaces. The three-body dissociation channel is found to be the dominate dissociation channel for HXeBr. Based on the obtained potentials, low-lying vibrational energy levels of HXeBr calculated using the Lanczos algorithm is found to be in good agreement with the available experimental band origins.

关键词： HXeBr Vibrational energy level Potential energy surface

Theoretical study on the potential energy surface and vibrational energy levels of HXeI

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Chinese Chemical Letters 2008年第4期19卷 501-504页

作者： Zheng Guo Huang en cui yang Dai Qian Xie Chemistry and Life Science College Tianjin Normal UniversityTianjin 300387China Institute of Theoretical and Computational Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

The potential energy surface for the electronic ground state of the HXeI molecule is constructed by using the internally contracted multi-reference configuration interaction with the Davidson correction（icMRCI＋Q）method and large basis sets. The stabilities and dissociation barriers are identified from the potential energy *** three-body dissociation channel is found to be the dominate dissociation channel for *** on the obtained potentials,vibrational energy levels of HXeI are calculated using the Lanczos *** theoretical results are in excellent agreement with the available observed values.

关键词： HXel Vibrational energy level Potential energy surface

Improved Segmented Belief Propagation List Decoding for Polar Codes with Bit-Flipping

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China Communications 2024年第3期21卷 19-36页

作者： Mao Yinyou yang Dong Liu Xingcheng Zou en School of Electronics and Information Technology(SEIT) Sun Yat-sen University(SYSU)Guangzhou 510006China School of Information Science Guangzhou Xinhua UniversityGuangzhou 510520China Southern Marine Science and engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

Belief propagation list(BPL) decoding for polar codes has attracted more attention due to its inherent parallel nature. However, a large gap still exists with CRC-aided SCL(CA-SCL) *** this work, an improved segmented belief propagation list decoding based on bit flipping(SBPL-BF) is proposed. On the one hand, the proposed algorithm makes use of the cooperative characteristic in BPL decoding such that the codeword is decoded in different BP decoders. Based on this characteristic, the unreliable bits for flipping could be split into multiple subblocks and could be flipped in different decoders simultaneously. On the other hand, a more flexible and effective processing strategy for the priori information of the unfrozen bits that do not need to be flipped is designed to improve the decoding convergence. In addition, this is the first proposal in BPL decoding which jointly optimizes the bit flipping of the information bits and the code bits. In particular, for bit flipping of the code bits, a H-matrix aided bit-flipping algorithm is designed to enhance the accuracy in identifying erroneous code bits. The simulation results show that the proposed algorithm significantly improves the errorcorrection performance of BPL decoding for medium and long codes. It is more than 0.25 d B better than the state-of-the-art BPL decoding at a block error rate(BLER) of 10^(-5), and outperforms CA-SCL decoding in the low signal-to-noise(SNR) region for(1024, 0.5)polar codes.

关键词： belief propagation list(BPL)decoding bit-flipping polar codes segmented CRC

Spatial distribution of shallow landslides caused by Typhoon Lekima in 2019 in Zhejiang Province, China

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Journal of Mountain Science 2024年第5期21卷 1564-1580页

作者： cui Yulong yang Liu XU Chong ZHenG Jun School of Civil engineering and Architecture Anhui University of Science and TechnologyHuainan 232001China National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Department of Civil engineering Zhejiang UniversityHangzhou 310058China

In recent years, the coastal region of Southeast China has witnessed a significant increase in the frequency and intensity of extreme rainfall events associated with landfalling typhoons. The hilly and mountainous terrain of this area, combined with rapid rainfall accumulation, has led to a surge in flash floods and severe geological hazards. On August 10, 2019, Typhoon Lekima made landfall in Zhejiang Province, China, and its torrential rainfall triggered extensive landslides, resulting in substantial damage and economic losses. Utilizing high-resolution satellite images, we compiled a landslide inventory of the affected area, which comprises a total of 2,774 rainfallinduced landslides over an area of 2965 km2. The majority of these landslides were small to mediumsized and exhibited elongated, clustered patterns. Some landslides displayed characteristics of high-level initiation, obstructing or partially blocking rivers, leading to the formation of debris dams. We used the inventory to analyze the distribution pattern of the landslides and their relationship with topographical, geological, and hydrological factors. The results showed that landslide abundance was closely related to elevation, slope angle, faults, and road density. The landslides were predominantly located in hilly and low mountainous areas, with elevations ranging from 150 to 300 m, slopes of 20 to 30 degrees, and a NE-SE aspect. Notably, we observed the highest Landslide Number Density(LND) and Landslide Area Percentage(LAP) in the rhyolite region. Landslides were concentrated within approximately 4 km on either side of fault zones, with their size and frequency negatively correlated with distances to faults, roads, and river systems. Furthermore, under the influence of typhoons, regions with denser vegetation cover exhibited higher landslide density, reaching maximum values in shrubland areas. In areas experiencing significantly increased concentrated rainfall, landslide density also showed a corr

关键词： Typhoon rainfall Landslide characteristics Spatial distribution Southeast coastal region

Multiscale analysis-based peridynamic simulation of fracture in porous media

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Frontiers of Structural and Civil engineering 2024年第1期18卷 1-13页

作者： Zihao yang Shangkun SHen Xiaofei GUAN Xindang HE Junzhi cui School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an 710072China School of Mathematical Sciences Tongji UniversityShanghai 200092China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710072China LSEC ICMSECAcademy of Mathematics and Systems ScienceCASBeijing 100190China

The simulation of fracture in large-scale structures made of porous media remains a challenging *** techniques either assume a homogeneous model,disregarding the microstructure characteristics,or adopt a micro-mechanical model,which incurs an intractable computational cost due to its complex stochastic geometry and physical properties,as well as its nonlinear and multiscale *** this study,we propose a multiscale analysis-based dual-variable-horizon peridynamics(PD)model to efficiently simulate macroscopic structural *** influence of microstructures in porous media on macroscopic structural failure is represented by two PD parameters:the equivalent critical stretch and *** equivalent critical stretch is calculated using the microscale PD model,while the equivalent micro-modulus is obtained through the homogenization method and energy density equivalence between classical continuum mechanics and PD *** examples of porous media with various microstructures demonstrate the validity,accuracy,and efficiency of the proposed method.

关键词： porous media multiscale variable-horizon peridynamic equivalent critical stretch equivalent micro-modulus

Potential application of radiant floor cooling systems for residential buildings in different climate zones

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Building Simulation 2024年第4期17卷 543-560页

作者： Mengying cui yang Song Yudong Mao Kaimin yang Jiying Liu Zhe Tian School of Thermal engineering Shandong Jianzhu UniversityJinan250101China School of environmental Science and engineering Tianjin UniversityTianjin300072China Key Lab of Building environment and energy of Tianjin Tianjin UniversityTianjin300072China

A radiant floor cooling system(RFCS)is a high-comfort and low energy consumption system suitable for residential *** floor systems usually work with fresh air,and their operating performance is affected by climatic *** and outdoor environmental disturbances and the system’s control strategy affect the indoor thermal comfort and energy efficiency of the ***,a multi-story residential building model was established in this *** system simulation program was used to study the operation dynamics of three control strategies of the RFCS based on the calibrated ***,the performance of the control strategies in five climate zones in China were compared using multi-criteria decision-making in *** results show that control strategy has a negligible effect on condensation risk,but the thermal comfort and economic performance differ for different control *** adaptability of different control strategies varies in different climate zones based on the consideration of multiple *** performance of the direct-ground cooling source system is better in Hot summer and warm winter *** variable air volume control strategy scores higher in Serve cold and Temperate zones,and the hours exceeding thermal comfort account for less than 3%of the total simulation ***,it is suggested to choose the RFCS control strategy for residential buildings according to the climate zone characteristics,to increase the energy *** results provide a reliable reference for implementing RFCSs in residential buildings.

关键词： control strategy radiant floor cooling system residential building energy efficiency climate zones

A GNSS Anti-Spoofing Technique Based on the Spatial Distribution Characteristic of the Residual Vectors

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Tsinghua Science and Technology 2024年第2期29卷 457-468页

作者： Qi'an Wu Xiaowei cui Mingquan Lu Pengxiang yang Peng Wu Department of Electronic enginnering Tsinghua UniversityBeijing 100084China Xi’an Modern Control Technology Research Institute Xi’an 710065China

Anti-spoofing is becoming a crucial technique for applications with high navigation accuracy and reliability ***-spoofing technique based on Receiver Autonomous Integrity Monitoring(RAIM)is a good choice for most Global Navigation Satellite System(GNSS)receivers because it does not require any change to the hardware of the ***,the conventional RAIM method can only detect and mitigate a single spoofing *** improved RAIM methods can deal with more spoofing signals,but the computational complexity increases dramatically when the number of satellites in view increase or need additional *** paper proposes a new RAIM method,called the SRV-RAIM method,which has a very low computation complexity regardless of the number of satellites in view and can deal with any number of spoofing *** key to the new method is the spatial distribution characteristic of the Satellites'Residual Vectors(SRV).In replay or generative spoofing scenarios,the pseudorange measurements of spoofing signals are consistent,the residual vectors of real satellites and those of spoofing satellites have good separation characteristics in spatial *** on this characteristic,the SRV-RAIM method is proposed,and the simulation results show that the method can separate the real signals and the spoofing signals with an average probability of 86.55%in the case of 12 visible satellites,regardless of the number of spoofing *** to the conventional traversal-RAIM method,the performance is only reduced by 3.59%,but the computational cost is reduced by 98.3%,so most of the GNSS receivers can run the SRV-RAIM algorithm in time.

关键词： Global Navigation Satellite System(GNSS) anti-spoofing Receiver Autonomous Integrity Monitoring(RAIM) Satellites'Residual Vectors(SRV)

Immediate implantation of ultrafine fiber slow-release system based on cell electrospinning to induce osteogenesis of mesenchymal stem cells

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Regenerative Biomaterials 2024年第2期3卷 76-87页

作者： Tao Lu Long yang Zhuoyang Li Yin Liu Shun'en Xu Chuan Ye Department of Orthopaedics The Affliated Hospital of Guizhou Medical UniversityGuiyang 550004China Department of Orthopaedics The First People's Hospital of GuiyangGuiyang 550004China Center for Tissue engineering and Stem Cell Research Guizhou Medical UniversityGuiyang 550004China Department of Otolaryngology Head and Neck Surgery Xinqiao HospitalArmy Medical University(Third Military Medical University)Chongqing 400037China Department of Dental implant Stomatological Hospital of GuiyangGuiyang 550000China

This study presents the development and evaluation of a poly(3-hydroxybutyrate-co-4-hydroxybutyrate)(P34HB)ultrafine fiber slow-release system for in vivo osteogenic induction of human umbilical cord mesenchymal stem cells(HUCMSCs).Utilizing dual-nozzle and cell electrospinning techniques,the system encapsulates L-ascorbic acid-2-phosphate magnesium(AsP),βB-glycerophosphate sodium and dexamethasone(DEX)within the'fbers,ensuring sustained osteogenic *** scaffold's morphology,characterization,hydrophilicity,mechanical properties and cellular behavior were *** subcutaneous implantation in rabbits was con-ducted to observe its ectopic osteogenic induction *** fabricated P34HB ultrafine fiber slow-release *** ization *** distribution of HUCMSCs and inducing components within the scaffold,with no chemical reactions affecting the active *** vitro tests showcased a prolonged release of DEX and ASP,while biocompatibility assays highlighted the scaffold's suitability for cellular *** Red,type I collagen,and osteopontin(OPN)staining verifed the scaffold's potent osteogenic induction effect on ***,immediate implantation into New Zealand White rabbits led to significant new bone formation within 8 *** findings underscore the system's potential for immediate in vivo implantation without prior in vitro induction,marking a promising advancement in bone tissue engineering.

关键词： bone tissue engineering cell electrospinning in vivo induction immediate implantation biomaterials