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Frontiers of Structural and Civil Engineering 2022年第3期16卷 267-280页

作者： Huailei CHENG Liping LIU lijun sun The Key Laboratory of Road and Traffic Engineering(Ministry of Education) Tongji UniversityShanghai 201804China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China

Asphalt pavement is a key component of highway infrastructures in China and *** asphalt pavement design and condition assessment,the modulus of the asphalt mixture layer is a crucial ***,this parameter varies between the laboratory and field loading modes(i.e.,loading frequency,compressive or tensile loading pattern),due to the viscoelastic property and composite structure of the asphalt *** present study proposes a comprehensive frequency-based approach to correlate the asphalt layer moduli obtained under two field and three laboratory loading *** field modes are vehicular and falling weight deflectometer(FWD)loading modes,and the laboratory ones are uniaxial compressive(UC),indirect tensile(IDT),and four-point bending(4PB)loading *** loading frequency is used as an intermediary parameter for correlating the asphalt layer moduli under different loading *** observations made at two field large-scale experimental pavements facilitate the correlation *** is found that the moduli obtained via laboratory 4PB tests are pretty close to those of vehicular loading schemes,in contrast to those derived in UC,IDT,and FWD modes,which need to be *** corresponding adjustment factors are experimentally *** applications of those adjustment factors are expected to ensure that the moduli measured under different loading modes are appropriately used in asphalt mixture pavement design and assessment.

关键词： asphalt mixture layer stiffness modulus loading mode UC/4PB/IDT FWD frequency

Inter-Carrier Interference-Aware Sparse Time-Varying Underwater Acoustic Channel Estimation Based on Fast Reconstruction Algorithm

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China Communications 2021年第3期18卷 216-225页

作者： Zhengqiang Yan Xinghai Yang lijun sun Jingjing Wang Qingdao University of Science and Technology Qingdao 266000Shandong ProvinceChina

In this paper,a fast orthogonal matching pursuit(OMP)algorithm based on optimized iterative process is proposed for sparse time-varying underwater acoustic(UWA)channel *** channel estimation consists of calculating amplitude,delay and Doppler scaling factor of each path using the received multi-path *** algorithm,called as OIP-FOMP,can reduce the computationally complexity of the traditional OMP algorithm and maintain accuracy in the presence of severe inter-carrier interference that exists in the time-varying UWA *** this algorithm,repeated inner product operations used in the OMP algorithm are removed by calculating the candidate path signature Hermitian inner product matrix in *** QR decomposition is used to estimate the path amplitude,and the problem of reconstruction failure caused by inaccurate delay selection is avoided by optimizing the Hermitian inner product *** analysis and simulation results show that the computational complexity of the OIP-FOMP algorithm is reduced by about 1/4 compared with the OMP algorithm,without any loss of accuracy.

关键词： underwater acoustic communication OFDM sparse channel estimation OIP-FOMP

Fatigue test setups and analysis methods for asphalt mixture: A state-of-the-art review

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Journal of Road Engineering 2022年第4期2卷 279-308页

作者： Huailei Cheng lijun sun Yuhong Wang Liping Liu Xingyu Chen The Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai 201804China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina

Fatigue performance evaluation on asphalt mixture provides an essential reference for asphalt mixture design and pavement structure *** fatigue test has been widely used by researchers and engineers to assess the fatigue performance of asphalt mixture,due to its low cost,high efficiency,and strong *** ensure performance assessment reliability,fatigue test operated in the laboratory needs to simulate the loading and environmental conditions occurring in the field asphalt *** a result,loading setups in laboratory fatigue tests,including loading mode,loading frequency,loading waveform,temperature,and the controlled mode,have been carefully devised by *** paper reviews the above common setups in fatigue tests,which aims to illustrate the classical and latest considerations as well as ideas proposed by researchers for improving fatigue test *** fatigue response data of asphalt mixture is measured from fatigue test,an analysis method is required to process the data and identify fatigue behaviors of the ***,the frequently-used fatigue data analysis methods include the fatigue life model,stiffness-modulus-based method,energy-based method,and viscoelastic continuum damage(VECD)*** paper also provides a review survey on the main concepts,indicators,and models included in those methods to facilitate their ***,the latest research progress and outputs related to the four methods are also introduced and discussed to reveal the state-of-the-art developments in this research area.

关键词： Asphalt mixture Fatigue Frequency Loading waveform Temperature VECD

The NAC transcription factor LuNAC61 negatively regulates fiber development in flax (Linum usitatissimum L.)

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Journal of Integrative Agriculture 2024年第3期23卷 795-805页

作者： Dongwei Xie Jing Li Wan Li lijun sun Zhigang Dai Wenzhi Zhou Jianguang Su Jian sun School of Life Sciences Nantong UniversityNantong 226019China Institute of Crop Cultivation and Tillage Heilongjiang Academy of Agricultural SciencesHarbin 150086China Institute of Bast Fiber Crops Chinese Academy of Agricultural SciencesChangsha 410221China Jiangsu Sanshu Biotechnology Co.Ltd. Nantong 226001China

Flax is a crucial fiber crop that exhibits excellent textile properties and serves as a model plant for investigating phloem fiber development. The regulation of multiple genes significantly influences fiber development, notably involving NAC(NAM, ATAF1/2, CUC2) transcription factors in forming the fiber secondary cell wall(SCW).Overexpression of LuNAC61 in flax resulted in sparse top meristematic zone leaves and significantly reduced stem cellulose content. Scanning electron microscopy and staining observations revealed a significant reduction in fiber bundles. β-Glucuronidase(GUS) staining analysis demonstrated high activity of the LuNAC61 promoter in the bast fibers of the flax stem. Additionally, several members of the LuPLATZ and LuCesA families exhibited significant coexpression with LuNAC61. Subcellular localization indicated the presence of LuPLATZ24 protein in the nucleus and cytoplasm, LuNAC61 protein exclusively in the nucleus, and LuCesA10 in the nucleus and endoplasmic reticulum. LuPLATZ24 positively regulates LuNAC61, whereas LuNAC61 negatively affects LuCesA10, suggesting the involvement of a metabolic network in regulating flax fiber development. In conclusion, this study provides a critical opportunity for a comprehensive and in-depth analysis of the mechanisms governing flax fiber development and the potential use of biotechnology to enhance flax fiber yield.

关键词： flax fiber development Lu NAC61 gene function gene interaction

Simulation model based on Monte Carlo method for traffic assignment in local area road network

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Frontiers of Structural and Civil Engineering 2009年第2期3卷 195-203页

作者： Yuchuan DU Yuanjing GENG lijun sun Key Lab.of Road and Traffic Engineering of the Ministry of Education Tongji UniversityShanghai 201804China

For a local area road network,the available traffic data of traveling are the flow volumes in the key intersections,not the complete OD *** the circumstance characteristic and the data availability of a local area road network,a new model for traffic assignment based on Monte Carlo simulation of intersection turning movement is provided in this *** good stability in temporal sequence,turning ratio is adopted as the important parameter of this *** formulation for local area road network assignment problems is proposed on the assumption of random turning *** traffic assignment model based on the Monte Carlo method has been used in traffic analysis for an actual urban road *** results comparing surveying traffic flow data and determining flow data by the previous model verify the applicability and validity of the proposed methodology.

关键词： traffic assignment local area road network turning ratio Monte Carlo method

Quantifying out-of-station waiting time in oversaturated urban metro systems

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Communications in Transportation Research 2022年第1期2卷 13-23页

作者： Kangli Zhu Zhanhong Cheng Jianjun Wu Fuya Yuan lijun sun Department of Civil Engineering McGill UniversityMontrealQuebecH3A 0C3Canada State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing100044China

Metro systems in megacities such as Beijing,Shenzhen,and Guangzhou are under great passenger demand *** peak hours,it is common to see oversaturated conditions(i.e.,passenger demand exceeds network capacity)and a popular control intervention is to restrict the entering rate by setting up out-of-station queueing with crowd control *** out-of-station waiting can make up a substantial proportion of total travel time but is often ignored in the *** out-of-station waiting is important to evaluating the social benefit and cost of metro services;however,out-of-station waiting is difficult to estimate because it leaves no trace in smart card transactions of *** this study,we estimate the out-of-station waiting time by leveraging the information from a small group of transfer passengers—those who transfer from nearby bus routes to the metro *** on the transfer interval of this small group,we infer the out-of-station waiting time for all passengers by a Gaussian Process regression and then use the estimated out-of-station waiting time to build queueing *** apply our method to the Tiantongyuan North station of Beijing metro;results show that the maximum out-of-station waiting time can reach 15 min,and the maximum queue length can be over 3000 *** find out-of-station waiting can cause significant travel costs and thus should be considered in analyzing transit performance,mode choice,and social *** the best of our knowledge,this paper is the first quantitative study for out-of-station waiting time.

关键词： Metro waiting time Smart card data Public transport Crowd management Gaussian processes

Reprogrammed mouse astrocytes retain a“memory”of tissue origin and possess more tendencies for neuronal differentiation than reprogrammed mouse embryonic fibroblasts

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Protein & Cell 2011年第2期2卷 128-140页

作者： Changhai Tian Yongxiang Wang lijun sun Kangmu Ma Jialin C.Zheng Laboratory of Neuroimmunology and Regenerative Therapy University of Nebraska Medical CenterOmahaNE 68198-5930USA Departments of Pharmacology/Experimental Neuroscience University of Nebraska Medical CenterOmahaNE 68198-5930USA Departments of Pathology/Microbiology University of Nebraska Medical CenterOmahaNE 68198-5930USA

Direct reprogramming of a variety of somatic cells with the transcription factors Oct4(also called Pou5f1),Sox2 with either Klf4 and Myc or Lin28 and Nanog generates the induced pluripotent stem cells(iPSCs)with marker similarity to embryonic stem ***,the difference between iPSCs derived from different origins is *** this study,we hypothesized that reprogrammed cells retain a“memory”of their origins and possess additional potential of related tissue *** reprogrammed primary mouse astrocytes via ectopic retroviral expression of OCT3/4,Sox2,Klf4 and Myc and found the iPSCs from mouse astrocytes expressed stem cell markers and formed teratomas in SCID mice containing derivatives of all three germ layers similar to mouse embryonic stem cells besides semblable *** test our hypothesis,we compared embryonic bodies(EBs)formation and neuronal differentiation between iPSCs from mouse embryonic fibroblasts(MEFsiPSCs)and iPSCs from mouse astrocytes(mAsiPSCs).We found that mAsiPSCs grew slower and possessed more potential for neuronal differentiation compared to *** results suggest that mAsiPSCs retain a“memory”of the central nervous system,which confers additional potential upon neuronal differentiation.

关键词： mouse astrocytes induced pluripotent stem cells neural progenitor cells neuronal differentiation

The Smart Road： Practice and Concept

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Engineering 2018年第4期4卷 436-437页

作者： lijun sun Hongduo Zhao Huizhao Tu Yu Tian College of Transportation Engineering Yongji University China

1. The smart road： Practice The concept of a super highway for intelligent connected vehicles and autonomous vehicles has been proposed in China, and pilot projects have been initiated. These projects include： modular pavement instrumented with distributed optical fiber, which has been built in Shanghai; self-healing asphalt pavements and self-snow- melting systems, which have been built in several provinces; and roads with humidity self-regulating subgrade, which have been built in Hunan Province.

关键词：智能联运车辆路基交通运输业道路施工

Urban rail transit disruption management: Research progress and future directions

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Frontiers of Engineering Management 2024年第1期11卷 79-91页

作者： Lebing WANG Jian Gang JIN lijun sun Der-Horng LEE School of Naval Architecture Ocean&Civil Engineeringand State Key Laboratory of Ocean EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Civil Engineering McGill UniversityMontrealQuebec H3A 0C3Canada ZJU-UIUC Institute Zhejiang UniversityHaining 314400China

Urban rail transit (URT) disruptions present considerable challenges due to several factors: i) a high probability of occurrence, arising from facility failures, disasters, and vandalism;ii) substantial negative effects, notably the delay of numerous passengers;iii) an escalating frequency, attributable to the gradual aging of facilities;and iv) severe penalties, including substantial fines for abnormal operation. This article systematically reviews URT disruption management literature from the past decade, categorizing it into pre-disruption and post-disruption measures. The pre-disruption research focuses on reducing the effects of disruptions through network analysis, passenger behavior analysis, resource allocation for protection and backup, and enhancing system resilience. Conversely, post-disruption research concentrates on restoring normal operations through train rescheduling and bus bridging services. The review reveals that while post-disruption strategies are thoroughly explored, pre-disruption research is predominantly analytical, with a scarcity of practical pre-emptive solutions. Moreover, future research should focus more on increasing the interchangeability of transport modes, reinforcing redundancy relationships between URT lines, and innovating post-disruption strategies.

关键词： urban rail transit disruption management resilient network train rescheduling bus bridging services

Effects of micro-oxygenation on the aroma of Cabernet Sauvignon wine from Ningxia,China

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International Journal of Agricultural and Biological Engineering 2022年第4期15卷 251-263页

作者： Zhong Zhang Qingchen Zhang Huiqing Wang Hongchuan Xia lijun sun Junxiang Zhang School of Life Sciences Ningxia UniversityYinchuan 750021China College of Pharmacy University of FloridaGainesville FL32610USA School of Agriculture Ningxia UniversityYinchuan 750021China School of Food and Wine Ningxia UniversityYinchuan 750021China China Wine Industry Technology Institute Yinchuan 750021China

Micro-oxygenation (MOX) is an effective post-harvest technique for the flavor improvement of grape wine. This study investigated the effect of MOX on the aroma quality of Ningxia wine for the first time. Three sub-region Cabernet Sauvignon dry red wines were treated with different levels of oxygen before or after malolactic fermentation. The wine aroma was analyzed through gas chromatography-mass spectrometry (GC-MS) and quantitative descriptive analysis (QDA) after six months of aging. The data obtained demonstrated that the dose and timing of oxygen addition were key factors influencing the effectiveness of MOX. The most noticeable modifications in wine aroma compounds were generated by an oxygen dosage of 30 (mL/L)/month added before malolactic fermentation. Predominantly, the concentrations of 2-phenylethanol, benzaldehyde, diacetyl, and 2,3-pentanedione showed an increased pattern upon MOX treatments. The sensory analysis revealed that MOX improved the aroma quality of wine by decreasing green and animal odors, meanwhile enhancing the olfactory intensities of dried fruits, flowers, and nuts. This work confirmed that MOX was suitable for aroma modification of Cabernet Sauvignon dry red wine from Ningxia and established a preliminary MOX procedure that can serve as a reference for future applications.

关键词： grape wine micro-oxygenation volatile organic compounds aroma profiles Ningxia