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| 1 | Acute myeloid leukemia is characterized by Wnt pathway inhibitor promoter hypermethylation显示文摘 | Elizabeth A. Griffiths Steven D. Gore Craig Hooker Michael A. McDevitt Judith E. Karp B. Douglas Smith Helai P. Mohammad Ying Ye James G. Herman Hetty E. Carraway | 2010 | Leukemia & Lymphoma2010，，9： | 3 |
| 2 | Technical Study of Slotted Pipe Working显示文摘TechnicalStudyofSlottedPipeWorkingYangHelai,SuFeng(TianjinInstituteofUrbanEngineering)Keywords:Ceramiccutter,Slottedpipe,Effe... | Yang Helai, Su Feng(Tianjin Institute of Urban Engineering) | 1996 | China Oil & Gas1996，3，4： | 3 |
| 3 | Multilevel data and Bayesian analysis in traffic safety显示文摘 | Helai H Mohamed A | 2010 | Accident Analysis Prevention2010，42，6： | 1 |
| 4 | Analysing taxi customer-search behaviour using Copula-based joint model显示文摘The drivers of vacant taxis tend to cruise the road network searching new passengers,which leads to additional traffic congestion,air pollution and other problems.This study introduces a Copula-based joint model to analyse destination selection and route choice behaviour in the customer-search process.A multinomial logit model is used to analyse the destination selection behaviour,and a path size logit model is used to explore the routes choice behaviour.Accordingly,the joint model applied Copula function is then established to analyse the correlation between these two behaviours.The destination customer generation rate,destination distance,route customer generation rate,path travel time,cumulative intersection delay,path size and route length are selected as explanatory variables.The taxis trajectory data were collected by global positioning system in Xidan District of Beijing City from September 2014 to February 2015.Using the log-likelihood,Bayesian information criterion as evaluation indexes to measure the fitting result,the joint model applied Copula function has the highest goodness-of-fit.The effect of explanatory variables on customer search behaviour is discussed based on the parameter estimation results.The results of this study are helpful to understand the customer-search behaviour of taxi drivers to reduce operating costs and improve the efficiency of the taxi operation system. | Helai Huang Zhenyuan Fang Yiwei Wang Jinjun Tang Xin Fu | 2022 | Transportation Safety and Environment2022，4，1： | 1 |
| 5 | Severity of driver inju- ry and vehicle damage in traffic crashes at intersec- tions: a Bayesian hierarchical analysis显示文摘 | Helai H Chor C Haque M | 2008 | Accident Analysis and Prevention2008，40，1： | 1 |
| 6 | Modeling conflict risk with real-time traffic data for road safety assessment:a copula-based joint approach显示文摘This study proposes a conflict-based traffic safety assessment method by associating conflict frequency and severity with shorttermtraffic characteristics. Instead of analysing historical crash data, this study employs microscopic trajectory data to quantify therelationship between conflict risk and traffic characteristics. The time-to-collision (TTC) index is used to detect conflicts, and a severityindex (SI) is proposed on the basis of time-integrated TTC. With SI, the k-means algorithm is applied to classify the conflict severitylevel. Then the severity of regional conflict risk is split to three levels. Zero truncated Poisson regression and ordered logit regressionmethods are employed to estimate the effects of short-term traffic characteristics on conflict frequency and severity, respectively.Furthermore, the copula-based joint modelling method is applied to explore the potential non-linear dependency of conflict riskoutcomes. A total of 18 copula models are tested to select the optimal ones. The HighD dataset from Germany is utilized to examinethe proposed framework. Both between-lane and within-lane factors are considered. Results show that the correlations betweentraffic characteristics and conflict risk are significant, and the dependency of conflict outcomes varies among different severity levels.The difference of speed variation between lanes significantly influences the conflict frequency and severity simultaneously. Findingsindicate that the proposed method is practicable to assess real-time traffic safety within a specific region by using short-term (30-second time interval) traffic characteristics. This study also contributes to develop targeted proactive safety strategies by evaluatingroad safety based on conflict risk, and considering different severity levels. | Yuping Hu Ye Li Chen Yuan Helai Huang | 2022 | Transportation Safety and Environment2022，4，3： | 1 |
| 7 | The lateral intercostals neurovascular free flap显示文摘 | Badram HA Helay MS Safe I | | 0，，： | 1 |
| 8 | Design and verification of a laser based device for pavement macrotexture measurement显示文摘 | WANG Weifeng YAN Xinping HUANG Helai | 2011 | Transporta- tion Research Part C: Emerging Technologies2011，19，4： | 1 |
| 9 | Multi-level data and Bayesian analysis in traffic safety显示文摘 | Helai H Mohamed A | 2010 | Accident Analysis Prevention2010，42，6： | 1 |
| 10 | Severity of driver injury and vehicle damage in traffic crashes at intersections: a Bayesian hierarchical analysis显示文摘 | Helai H Chor C Haque M | 2008 | Accident Analysis and Prevention2008，40，1： | 1 |
| 11 | Multilevel data and bayesian analysis in traffic safety显示文摘 | HELAI H MOHAMED A | | 0，，： | 1 |
| 12 | The modifiable areal unit problem in traffic safety:Basic issue, potential solutions and future research显示文摘This study fully addressed the modifiable areal unit problem(MAUP) that was well-known in geography but generally ignored by safety analysis. The basic issue of MAUP was introduced firstly with a case study to explicitly demonstrate the existence of the problem in macro level crash modeling, and then four potential strategies, i.e., using disaggregate data as possible,capturing spatial non-stationarity, designing optimal zoning systems, conducting sensitivity analysis to report the scope and magnitude of MAUP, were proposed and illustrated in an integrated way, followed by the future research directions. Results revealed that more efforts are desired to calibrate the state-of-art modeling technique at various levels of aggregation based on spatial homogeneity in traffic safety, transport characteristics, and demographical factors. The awareness of this problem in traffic safety domain is expected to the delineation of basic spatial units(e.g. the traffic safety analysis zones), as well as to provide new insights into the nature of MAUP in statistics and geography. | Pengpeng Xu Helai Huang Ni Dong | 2018 | Journal of Traffic and Transportation Engineering(English Edition)2018，5，1： | 1 |
| 13 | human papillomavims:beware the infection you can not see显示文摘 | Helay S | 2003 | Aust Fam Physician2003，32，5： | 1 |
| 14 | Applying Bayesian hierarchical models to examine motorcycle crashes at signalized intersections显示文摘 | Md. Mazharul Haque Hoong Chor Chin Helai Huang | 2009 | Accident Analysis and Prevention2009，，： | 1 |
| 15 | A PRELIMINARY STUDY ON MEANFIELD DECOMPOSITION显示文摘Two kinds of the empirical orthogonal function analysis method for decomposing the mean-field are developed and a comparison is made between them. It is proved that the mean-field can be decomposed using eigenvectors obtained from anomaly-field decomposition, and that more information can be obtained. An example of sea bottom mean temperature analysis shows its remarhabk effect in depicting the distribution features of variousfactors, such as cold water mass, currents and radiation.A few problems concerning the efficiency of the method are discussedand two matrices of relationship which represent the space-time characteristics of the field are derived. The formulae of space-time transformation are obtained conveniently. | Ma Helai and Su Yusong(Received March 6, 1987 accepted September 15, 1987) | 1989 | 中国海洋大学学报(自然科学版)1989，27，S1： | 0 |
| 16 | Safety effects of work zone advisory systems under the intelligent connected vehicle environment:a microsimulation approach显示文摘Purpose–This study aims to investigate the safety effects of work zone advisory systems.The traditional system includes a dynamic message sign(DMS),whereas the advanced system includes an in-vehicle work zone warning application under the connected vehicle(CV)environment.Design/methodology/approach–A comparative analysis was conducted based on the microsimulation experiments.Findings–The results indicate that the CV-based warning system outperforms the DMS.From this study,the optimal distances of placing a DMS varies according to different traffic conditions.Nevertheless,negative influence of excessive distance DMS placed from the work zone would be more obvious when there is heavier traffic volume.Thus,it is recommended that the optimal distance DMS placed from the work zone should be shortened if there is a traffic congestion.It was also revealed that higher market penetration rate of CVs will lead to safer network under good traffic conditions.Research limitations/implications–Because this study used only microsimulation,the results do not reflect the real-world drivers’reactions to DMS and CV warning messages.A series of driving simulator experiments need to be conducted to capture the real driving behaviors so as to investigate the unresolved-related issues.Human machine interface needs be used to simulate the process of in-vehicle warning information delivery.The validation of the simulation model was not conducted because of the data limitation.Practical implications–It suggests for the optimal DMS placement for improving the overall efficiency and safety under the CV environment.Originality/value–A traffic network evaluation method considering both efficiency and safety is proposed by applying traffic simulation. | Suyi Mao Guiming Xiao Jaeyoung Lee Ling Wang Zijin Wang Helai Huang | 2021 | Journal of Intelligent and Connected Vehicles2021，4，1： | 0 |
| 17 | Correlation of the epidemic spread of COVID-19 and urban population migration in the major cities of Hubei Province, China显示文摘This study analyses the relationship between the epidemic spread of COVID-19 and urban population migration in Hubei Province,China.Based on an improved gravity model,the population inflow numbers for each city from 10 January to 23 February are estimated.A correlation analysis is done to reveal the impact of population inflow on the number of infected people in the 14 days after 23 January,the day Wuhan was locked down.The results show that:(i)the population outflow from Wuhan was mostly distributed between Xiaogan,Huanggang,Ezhou and Huangshi in Hubei Province;(ii)the number of accumulated confirmed patients is closely associated with inflows from Wuhan,which displayed by correlation coefficient 1 with a mean of 0.88 and a maximum of 0.93.Meanwhile,there is a weak correlation between the number of people that came from cities except Wuhan and accumulated confirmed patients,which indicated by correlation coefficient 2 with a mean of 0.65 and a maximum of 0.75;and(iii)the total population inflow is a greater predictor of epidemic spread than the population inflow from Wuhan. | Qun Chen Jiao Yan Helai Huang Xi Zhang | 2021 | Transportation Safety and Environment2021，3，1： | 0 |
| 18 | Optimization of depreciation subsidy policy strategies for electric two-wheelers for improving traffic safety显示文摘To improve the traffic safety of electric two-wheelers(ETW),China has promulgated ETW standardization policies.This policy requires local governments to take measures to guide the illegal ETWs out of use.Governments have implemented a depreciation subsidy scheme to encourage users to scrap illegal ETWs early.When designing the subsidy scheme,effectively improving the ETWs’traffic safety at the road network level while saving government expenses is essential for the sustainable implementation of the policy.This study proposes an optimization method for depreciation subsidy design incorporating traffic safety evaluation.Based on the policy scheme,this study formulates a risk assessment model for the ETW traffic network to characterize the effect of the subsidy on improving safety.Then,we use the bi-level programming approach to model the subsidy strategy design problem.The upper-level problem reflects the goal of policymakers to maximize safety improvement and minimize government expenses.The lower-level problem describes the route choices of ETW users.The optimal subsidy design under different safety-expense trade-offs is analysed based on the Nguyen and Dupuis network and a real network extracted from Changsha City in China.The results show that specific subsidy schemes effectively improve road safety without a large government spending.When themarket price or service life of ETWs increases,the government spending on the same safety goal increases.The government should comprehensively consider the safety effect of financial expense and the situation of the local ETW market before selecting reasonable subsidy strategies. | Xintong Li Helai Huang Chunyang Han Guangming Xu Jaeyoung Lee Cheng Hu | 2022 | Transportation Safety and Environment2022，4，3： | 0 |
| 19 | DEVELOPMENT AND VIBRATION ANALYSIS OF CERAMIC ROCKER ARM显示文摘DEVELOPMENTANDVIBRATIONANALYSISOFCERAMICROCKERARMDEVELOPMENTANDVIBRATIONANALYSISOFCERAMICROCKERARMYangHelai;ChengGeng;SuFeng(... | Yang Helai Cheng Geng Su Feng(Tianjin Institute of Urban Engineering) | 1995 | Chinese Journal of Mechanical Engineering1995，8，4： | 0 |
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