Preparation of Aligned Steel Fiber Reinforced Cementitious Composite and Its Flexural Behavior

The aim of this work is to present an approach, inspired by the way in which a compass needle maintains a consistent orientation under the action of the ...

Hebei University of Technology

In general, model-independent algorithms are sensitive to noise during laser particle size measurement. An improved conjugate gradient algorithm (ICGA) that can be used to invert particle size distribution (PSD) from diffraction data is presented. By use of the ICGA to invert simulated data with multiplicative or additive noise, we determined that additive noise is the main factor that induces distorted results. Thus the ICGA is amended by introduction of an iteration step-adjusting parameter and is used experimentally on simulated data and some samples. The experimental results show that the sensitivity of the ICGA to noise is reduced and the inverted results are in accord with the real PSD.

Noise effect in an improved conjugate gradient algorithm to invert particle size distribution and the algorithm amendment.

The accuracy of the measurement results will be influenced by the ambient temperature in the real-time monitoring based on Differential Optical Absorption Spectroscopy (DOAS). A novel method to improve the temperature robustness of DOAS technology is adopted by two-dimensional correlation spectroscopy technology. Two-dimensional correlation is used to analyse the SO2 absorption cross section at different temperatures. The diagonal slices of synchronization correlation spectroscopy which come from dynamic absorption cross section are obtained. The wavelength 300.5-310 nm is used as the preferred inversion wavelength range based on the slices. The field measurement results and reference value are compared. Results show that the 24-hour average measurement error is 22.5% at 290-310 nm and that at 300.5-310 nm is 9.9%. The correlation coefficients are 0.9496 and 0.7808, respectively. Two-dimensional correlation DOAS technology can be applied to enhance the robustness of temperature, and to improve the accuracy of the measurement results.

[Improving the temperature robustness of the DOAS based on two-dimensional correlation spectroscopy technology].

The differential optical absorption spectroscopy system is presented to monitor air pollutants, such as SO2, NO2, etc. The system employs a reflective telescope to collimate light source and focus absorbed light. A combined transmitting and receiving fiber bundle is set to the focus of a concave mirror. A Xenon lamp works as the light source. The light is coupled into the transmitting fiber, and then collimated by the reflective telescope system. After absorbed by the pollutants, the light is reflected by a pyramid mirror far away the telescope. Then the absorbed light is incident on the concave mirror the second time, and focused on the focal plane again. The receiving fiber induces the light which carries the information of the measured gas into a spectrometer. We can get the concentration of the pollutants by DOAS algorithm. Experimental results show that the proposed method can be adopted to measure some pollutants in air quality monitoring.

[Air pollutants study by differential optical absorption spectroscopy with transmit-receive fibers].

The process of bid/no-bid decision-making is su bjected to uncertainty and influence of complex criteria. This paper proposed an application of the integration of rough sets (RS) and improved general regression neural network (GRNN) based on niche particle swarm optimization (NPSO) algorithm for tendering decision making. The decision table of RS and the attribution reduction was processed by MIBARK algorithm to simply the samples of GRNN. In order to improve the general regression neural network (GRNN) network performance, the niche particle swarm optimization (NPSO) was used to optimize the spread parameter σ of GRNN neural network, then a novel Bid/no-bid decision model was established based on RS and NPSO-GRNN neural network algorithm. The applicability of the proposed model was tested using real cases in Beijing. The results indicate that NPSO-GRNN algorithm has an advantage such as in prediction accuracy and generalization ability. The proposed decision support system approach is useful to help manager to make better Bid/no-bid decisions in uncertain construction markets, so they can take steps to prevent bid distress. 

A dynamic novel approach for bid/no-bid decision-making.

Since parameters of the parallel external fixator are difficult to measure and calculate in real applications, this study developed computer software that can help the doctor measure parameters using digital technology and generate an electronic prescription for deformity correction.

The computer-aided parallel external fixator for complex lower limb deformity correction.

The role of graphene oxide (GO) on anaerobic digestion (AD) of swine manure concerning the performance, microbial community and antibiotic resistance genes (ARGs) reduction was investigated. Results showed that methane production was reduced by 13.1%, 10.6%, 2.7% and 17.1% at GO concentration of 5mg/L, 50mg/L, 100mg/L and 500mg/L, respectively, but propionate degradation was enhanced along with GO addition. Both bacterial and archaeal community changed little after GO addition. AD could well reduce ARGs abundance, but it was deteriorated at the GO concentration of 50mg/L and 100mg/L and enhanced at 500mg/L, while no obvious changes at 5mg/L. Network and SEM analysis indicated that changes of each ARG was closely associated with variation of microbial community composition, environmental variables contributed most to the dynamics of ARGs indirectly, GO influenced the ARGs dynamics negatively and (heavy metal resistance genes (MRGs)) influenced the most directly.

Effects of graphene oxide on the performance, microbial community dynamics and antibiotic resistance genes reduction during anaerobic digestion of swine manure.

The evaluation of traffic emissions control efficiency from various levels is a key issue while selecting an optimal plan for the sustainable development of urban transportation. The conventional multi-criteria evaluation methods cannot deal with the determination and uncertainty of each indicator, and ignore influence of the decision-maker's risk attitude on the evaluation results. This study proposed the use of a multi-attribute decision-making model to evaluate the traffic pollution control operational efficiency by integrating 11 hybrid-type indicators related to the plan implementation, traffic flow, and emissions. It also revealed the relationship between the preference of each decision-maker on these evaluation indicators and the threshold changes in the emissions control efficiency ranking. Case studies performed on the four plans showed that the evaluation value of emissions control efficiency for each plan was related to the decision-maker's risk attitude, and the efficiency ranking was decided by their threshold contact degrees.

A multi-attribute decision-making model for the evaluation of uncertainties in traffic pollution control planning.

This study investigated the fate of antibiotic resistance genes (ARGs) during mesophilic (mAD) and thermophilic digestion (tAD) of swine manure through zero valent iron (ZVI), natural zeolite and Dnase addition. Changes of microbial community, intI1, heavy metal resistance genes (MRGs) and virulence factors (VFs) were followed to clarify the influencing factors to ARGs reduction. Results showed that AD could realize ARGs reduction with tAD superior to mAD, and ZVI and natural zeolite could further enhance the reduction, especially for natural zeolite addition at mAD. The reduction efficiency of the relative abundance of ARGs was increased by 33.3% and 138.5% after ZVI and natural zeolite addition, respectively, but Dnase deteriorated ARGs reduction at mAD. Most of ARGs could be reduced effectively except sulII and tetM. Network analysis and partial redundancy analysis indicated that co-occurrence of MRGs followed by microbial community contributed the most to the variation of ARGs fate among treatments.

Impacts of zero valent iron, natural zeolite and Dnase on the fate of antibiotic resistance genes during thermophilic and mesophilic anaerobic digestion of swine manure.

Luansu Wei

School of Civil and Transportation Engineering

Hebei University of Technology

Preparation of Aligned Steel Fiber Reinforced Cementitious Composite and Its Flexural Behavior

Luansu Wei

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}School of Civil and Transportation Engineering

Hebei University of Technology

Preparation of Aligned Steel Fiber Reinforced Cementitious Composite and Its Flexural Behavior

School of Civil and Transportation Engineering