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Liu W.-W.,Tsinghua National Laboratory for Information Sciences and Technology | Cai M.,Tsinghua National Laboratory for Information Sciences and Technology | Yuan H.,Tsinghua National Laboratory for Information Sciences and Technology | Shi X.-B.,Beijing General Municipal Engineering Design and Research Institute Co. | And 2 more authors.
Proceedings of the 9th International Symposium on Chinese Spoken Language Processing, ISCSLP 2014 | Year: 2014

A recently introduced deep neural network (DNN) has achieved some unprecedented gains in many challenging automatic speech recognition (ASR) tasks. In this paper deep neural network hidden Markov model (DNN-HMM) acoustic models is introduced to phonotactic language recognition and outperforms artificial neural network hidden Markov model (ANN-HMM) and Gaussian mixture model hidden Markov model (GMM-HMM) acoustic model. Experimental results have confirmed that phonotactic language recognition system using DNN-HMM acoustic model yields relative equal error rate reduction of 28.42%, 14.06%, 18.70% and 12.55%, 7.20%, 2.47% for 30s, 10s, 3s comparing with the ANN-HMM and GMM-HMM approaches respectively on National Institute of Standards and Technology language recognition evaluation (NIST LRE) 2009 tasks. © 2014 IEEE.

Zeng T.,University of South China | Li D.,Beijing University of Technology | Jiang X.,University of South China | Qiu W.-X.,Beijing General Municipal Engineering Design and Research Institute Co. | And 3 more authors.
Journal of Water Process Engineering | Year: 2016

Anaerobic ammonium-oxidizing (anammox) process is considered to be a sustainable option for nitrogen removal. Application of this process, however, is limited by the availability of high strength nitrogen. In this study, an anaerobic ammonium oxidation (ANAMMOX) biofilter to treat sewage was deployed at ambient temperatures (18-21.5 °C), and the corresponding microbial community was investigated. The ammonia and nitrite initial loading rates were 0.154 kgN/(m3 d) and 0.2 kgN/(m3 d), respectively. ANAMMOX bacteria were rapidly enriched within 25 days and achieved a sustainable increase in the nitrogen removal rate (NRR) for sewage treatment. A final NRR of 0.99 kg N/(m3 d) was seen at the 80 day point. Observations that combined fluorescence in situ hybridization (FISH) analysis with scanning electron microscopy (SEM) observations confirmed that ANAMMOX bacteria were dominant in the cultivated biofilm, accounting for 39.5 (±1.6)% of total bacteria. Denaturing gradient gel electrophoresis (DGGE) and phylogenetic analysis identified five genera of bacteria: Pseudomonas, Acinetobacter, Nitrosomonas, Candidatus Brocadia fulgida and Ferruginibacter. Of these, Candidatus Brocadia fulgida was the functional ANAMMOX bacteria in the reactor. Candidatus Brocadia fulgida could survive comfortably in sewage, and co-existed with Nitrosomonas and denitrifying bacteria. © 2016 Elsevier Ltd.

An L.,Harbin Institute of Technology | Ling X.,Harbin Institute of Technology | Wang M.,Beijing General Municipal Engineering Design and Research Institute Co. | Li Q.,Harbin Institute of Technology | And 2 more authors.
Electronic Journal of Geotechnical Engineering | Year: 2015

A series of dynamic triaxial tests were carried out to investigate the variation laws of the dynamic parameters of typical silt soil in seasonal frozen region obtained from the embankment along the Harbin-Daqing railway subjected to train loading. Effects on the dynamic elastic modulus and damping ratio of the repeat freeze-thaw cycles, moisture content, loading frequency, and confining pressure were studied. The relationship between the modulus ratio and dynamic strain under various factors was proposed. The results show that the repeat freeze-thaw cycles have a significant effect on the backbone curve of silt soil in seasonal frozen region. The dynamic stress tends to decrease with the increase of the number of repeat freeze-thaw cycles for a certain dynamic strain. The maximum dynamic elastic modulus increases with the increasing confining pressure or the decreasing moisture content. The damping ratio increases with the number of repeat freeze-thaw cycles increases and it increases considerably after five freeze-thaw cycles. In addition, the damping ratio is strongly influenced by the loading frequency and it increases dramatically under 4Hz in comparison with that under 2Hz. Under the condition of the same dynamic strain, the damping ratio increases with the moisture content increases. © 2015 ejge.

Lu W.,Tianjin University | Zhang L.,Tianjin University | Bai F.,Beijing General Municipal Engineering Design and Research Institute Co.
Engineering, Construction and Architectural Management | Year: 2016

Purpose - The learning ability on critical bargaining information contributes to accelerating construction claim negotiations in the win-win situation. The purpose of this paper is to study how to apply Zeuthen strategy and Bayesian learning to simulate the dynamic bargaining process of claim negotiations with the consideration of discount factor and risk attitude. Design/methodology/approach - The authors first adopted certainty equivalent method and curve fitting to build a party's own curve utility function. Taking the opponent's bottom line as the learning goal, the authors introduced Bayesian learning to refine former predicted linear utility function of the opponent according to every new counteroffer. Both parties' utility functions were revised by taking discount factors into consideration. Accordingly, the authors developed a bilateral learning model in construction claim negotiations based on Zeuthen strategy. Findings - The consistency of Zeuthen strategy and the Nash bargaining solution model guarantees the effectiveness of the bilateral learning model. Moreover, the illustrative example verifies the feasibility of this model. Research limitations/implications - As the authors developed the bilateral learning model by mathematical deduction, scholars are expected to collect empirical cases and compare actual solutions and model solutions in order to modify the model in future studies. Practical implications - Negotiators could refer to this model to make offers dynamically, which is favorable for the parties to reach an agreement quickly and to avoid the escalation of claims into disputes. Originality/value - The proposed model provides a supplement to the existing studies on dynamic construction claim negotiations. © Emerald Group Publishing Limited.

Li Y.,Beijing Jiaotong University | Li Y.,Beijing General Municipal Engineering Design and Research Institute Co. | Wang L.-J.,Beijing Jiaotong University | Luan G.-R.,Beijing Jiaotong University | Zhang G.-Z.,Beijing Jiaotong University
Tiedao Xuebao/Journal of the China Railway Society | Year: 2014

Experimental study was carried out on engineering characteristics of the thick soft-soil composite foundation under large-area preloading in the throat area of the Jinan West Railway Station of the Beijing-Shanghai High-speed Railway. The changing law of excess pore water pressures, settlement deformations and pile-soil stresses at different positions and depths with time and soil filling heights was analyzed, thus providing theoretical basis for design and construction of engineering projects of a kind in the same area. The research results show as follows: (1) Excess pore water pressures of the composite foundation in the station throat area increase with growth of loads and upon reaching their peak value gradually scatter and disappear as time prolongs. The change of excess pore water pressures lags behind the change of loads slightly. The maximum excess pore water pressure appears in the upper part of under layer. In the underlayer, excess pore water pressures decrease gradually with increasing of depths. (2) For the composite foundation of the station throat area, the settlement reaches the maximum in the middle of the area reinforced with Pile 25 m CFG. Pipe Pile 35 m PHC effectively decreases the settement in the centre area of the station. Major compression settling happens at the bottom of the reinforced area and in the underlayer. (3) For the composite foundation of the station throat area, pile stresses, inter-pile soil stresses and pile-soil stress ratios demonstrate a generally decreasing trend from the centre of embankment outwards to edges. In embankment filling and preloading inter-pile soil stresses are passed on to piles in a gradually decreasing manner while pile-top stresses increase gradually until tending to get stablized. ©, 2014, Science Press. All right reserved.

Deng Y.,Beijing University of Technology | Chen C.,Beijing University of Technology | Li Q.,Beijing University of Technology | Li Q.,North China Institute of Science and Technology | And 4 more authors.
Atmospheric Environment | Year: 2015

Urban tunnels located in the city center areas, can alleviate traffic pressure and provide more convenient traffic for people. Vehicles emit pollutants that are significant contributors to air pollution inside and at the outlet of tunnels. Ventilation is the most widely used method to dilute pollutants in tunnels. To calculate the design required air volume flow accurately, vehicle emissions should be exactly determined. Emission factors are important parameters to estimate vehicle emissions. To characterize carbon monoxide (CO) and nitrogen oxides (NOX) emission factors for a mixed vehicle fleet under real-world driving conditions of urban China, we measured CO and NOX concentrations in Shanghai East Yan'an Road tunnel and Changsha Yingpan Road tunnel in 2012 and 2013. In-use fleet average CO and NOX emission factors were calculated according to tunnel pollutants mass balance models. The results showed that the maximum CO concentration in August was 86 ppm, while in October it was 45 ppm in Shanghai East Yan'an Road tunnel. The maximum concentrations of CO and NOX were 33 ppm and 2 ppm in Changsha Yingpan Road tunnel, respectively. In-use fleet average CO emission factors of East Yan'an Road tunnel, with gradient of -3% ~ 3%, were 1.266 (±0.889) ~ 3.974 (±2.189) g km-1 vehicle-1. In-use fleet average CO and NOX emission factors of Yingpan Road tunnel with gradient of -6% ~ 6% amounted to 0.754 (±0.561) ~ 6.050 (±5.940) g km-1 vehicle-1 and 0.121 (±0.022) ~ 0.818 (±0.755) g km-1 vehicle-1, respectively. The dependences of CO and NOX emission on roadway gradient and vehicle speed were found. The average CO and NOX emission factors increased with the ascending of roadway gradient as well as reverse with vehicle speed. These findings provide meaningful reference for ventilation design and environmental assessment of urban tunnels, and further help provide basic data to formulate relevant standards and norms. © 2015 Elsevier Ltd.

Li Q.,Beijing University of Technology | Li Q.,North China Institute of Science and Technology | Chen C.,Beijing University of Technology | Deng Y.,Beijing University of Technology | And 4 more authors.
Tunnelling and Underground Space Technology | Year: 2015

Environmental safety issues and ventilation problems caused by the construction of urban tunnel have increasingly been attracting people's attention. Previous studies in China have mainly focused on vehicle emissions and ventilation control technologies in road tunnels, resulting in a research gap on urban tunnel ventilation engineering design. Therefore, a detailed monitoring investigation was conducted from May 22 to June 2, 2013 in Changsha Yingpan Road Tunnel, China. The study aim was to measure the traffic characteristics, air velocity and the carbon monoxide (CO), nitrogen oxides (NOx) and fine particulate matter (PM2.5) concentrations in this tunnel, which has two lanes per bore and multiple ramps. Measurement results show that during the workday morning peak, the maximum traffic flow was 1560 passenger-car-unit/h per lane with vehicle speed around 33.6km/h in the eastbound tunnel, the average air velocity was 3.07m/s, and the proportion of the light-duty vehicles (LDV) was 97.3%. Under the traffic force (not open fan), the CO and NO average concentrations at the main tunnel outlet were 20.3ppm and 1.65ppm, respectively. The gas pollutant concentrations are effectively controlled within the multiple-ramps tunnel and the design air volume flow is noticeably reduced. The traffic air flow was found to provide 32.5% of the required air volume to dilute NOx in blocked traffic condition (vehicle speed of 10km/h). In addition, the PM2.5 concentration is mainly affected by the value of background outside the tunnel. The result can provide a quantitative assessment method to support pollutant concentration control and contribution of requested air volume by traffic flow in urban complex structure tunnel. © 2015 Elsevier Ltd.

Li J.M.,Beijing University of Technology | Huang Z.H.,Beijing University of Technology | Chen C.,Beijing University of Technology | Chuang J.,Beijing General Municipal Engineering Design and Research Institute Co. | Li Y.,Beijing General Municipal Engineering Design and Research Institute Co.
Progress in Civil, Architectural and Hydraulic Engineering - Selected Papers of the 4th International Conference on Civil, Architectural and Hydraulic Engineering, ICCAHE 2015 | Year: 2016

Fire safety in tunnels is a concern due to the large traffic flow, especially in a tunnel with a great slope. Experimental studies on the smoke spread in a small-scale titled tunnel are carried out. Effects of the titled gradients and longitudinal ventilation speed on the temperature distribution and smoke stratification downstream from the fire along the tunnel will be studied. The results show that the smoke spread upwards much faster with the slop gradient increasing, and a thick smoke layer was formed when smoke moved to the upward part of the tunnel and filled it up. The ventilation speed had a great influence on temperature distribution along the tunnel. Lower ventilation speed should be kept at the start of the fire to ensure the smoke layer not be destroyed downstream of the fire to give the tunnel users more time to escape. © 2016 Taylor & Francis Group, London.

Na Y.,Beijing General Municipal Engineering Design and Research Institute Co.
Applied Mechanics and Materials | Year: 2014

Highway tunnel mechanical and electrical engineering is a complex system which involves machinery, electronics, automation, communication and etc. In order to achieve high quality mechanical and electrical engineering standards, the construction and detection process should be planed and managed in details. © (2014) Trans Tech Publications, Switzerland.

Yin C.-X.,Beijing General Municipal Engineering Design and Research Institute Co.
Zhongguo Gonglu Xuebao/China Journal of Highway and Transport | Year: 2014

To get a convenient solution for the effect of temperature and shrinkage on steel-concrete composite beams by computer, with the introduction of geometrical-restriction relation, constitution relation and equilibrium condition, by integration of transformed section, the self stresses in composite section and statically indeterminate load vector in elements were calculated. The computing method was derived based on nonlinear thermal gradient of transformed section. Its relations to the methods of both differential equation and superposition method were also theoretically proved. The effect of slip on the composite beam was also analyzed. The results show that the computing method for transformed section can be used for both statically determinate and statically indeterminate composite beams; the programs based on this method can be used for both simply supported and continuous composite beams and the extent of effect of slip on composite beam is relative to the shear stiffness of the interface. ©, 2014, Xi'an Highway University. All right reserved.

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