فهرست مطالب q. wang

This study presents an efficient surrogate-based optimization (SBO) method of the aerodynamic performance of a contra-rotating open rotor (CROR). The objective was to maximize propulsion efficiency while reaching the target thrust coefficient at the cruise condition. To reduce the sample size and improve the optimization convergence speed, an infilling criterion was proposed based on the features of the interaction between the CROR front and rear rotors. The efficient front and rear rotors of the initial samples were selected and then combined to form the infilled samples. The results show that the infilled samples were closer to the Pareto front than the initial samples. For the six optimization parameters, 20 initial sample points were used, 11 samples were infilled, and the surrogate-based optimization was completed in five iterations. In total 43 samples were calculated during the optimization. The number of overall samples is approximately seven times the number of optimization parameters. The optimization results in parameter changes compared to the baseline and improved propulsion efficiency while meeting the thrust target. The optimization process increases the torque share of the rear rotor and changes the flow state at different radial positions, leading to a more uniform total pressure distribution at the outlet position, both circumferentially and radially.

To assess accurately the URT treatment planning system from the United Imaging Healthcare, the American Academy of Pain Medicine (AAPM) TG 119 test plans for Intensity-Modulated Radiation Therapy (IMRT) and Volumetric-Modulated Arc Therapy (VMAT) were used.

Based on the URT-Linac 506C, the plans were sent to the phantom. The overall accuracy was tested and examined using five geometry tests supplied in TG 119 for various treatment modes of IMRT and VMAT, with three types of beams using the Flattening Filter modality, estimated using the URT-TPS Monte Carlo algorithm. Moreover, a Farmer-type ion chamber was used to measure the point values, and a film was used to measure the fluence.

The disparities between the measured point doses and the anticipated doses for the FF photon beams for static MLC, dynamic MLC, and VMAT were within 2.16%, 1.89%, and 1.89%, respectively. The TG 119 report confidence limits were all met, and SMLC, DMLC, and VMAT had gamma passing rates greater than 99.80%, 99.60%, and 99.70%, respectively.

The URT treatment planning system and the URT-Linac 506C have correctly commissioned IMRT and VMAT processes, according to this analysis, which was completed following the recommendations given by TG 119.

This study addresses the measurement of three-dimensional (3D) bubble rising behaviour in still water with bubble equivalent diameters ranging from 2.61 mm to 5.11 mm using high-speed imaging and virtual stereo vision technology. The bubble shape, 3D trajectory/velocity, displacement angular frequency and terminal velocity of bubbles are analysed. The bubble equivalent diameter is obtained by the elliptic volume method. The bubbles are divided into small and large bubbles with a critical equivalent diameter of 4.49 mm, according to whether they are accompanied by deformation. The small bubbles (deq<4.49 mm) are spherical or ellipsoid, while the large bubbles (deq≥4.49 mm) exhibit ellipsoid, mushroom and hat shapes. The 3D trajectory is obtained by 3D reconstruction of bubble centroid coordinates. The rising trajectory of small bubbles shows 3D spiral motion, while the pitch increases gradually with the increase in the equivalent diameter. The trajectory of large bubbles is a two-dimensional (2D) zigzag. The bubble displacement curves in x- and z-directions are evaluated with third-order Fourier fitting. The results show that the bubble displacement frequency in the x and z-directions decreases with the increasing bubble diameter, and the displacement frequency in the xdirection is larger than that in the z-direction. The relative proportions of the viscous force, buoyancy, surface tension and inertial force on bubbles with different equivalent diameters are different, which leads to three trends in the vertical velocity of bubbles within the diameter range of this study. Finally, the bubble terminal velocity in still water is investigated. The terminal velocity first decreases and then increases with the increase in the equivalent diameter. The minimum value is 16.17 cm/s when the diameter of the bubble equivalent diameter is 4.49 mm. Moreover, the applicability of some classical prediction models is discussed.

Radiograph of hand and wrist has been widely used in children's bone age assessment (BAA). However, ionizing radiation may be harmful for children in the future. Therefore, alternative methods have been attempted for the evaluation of children's bone age. Here, we reported an automated volume scanner (AVS) in assessing the biological age of children in comparison with X-ray radiograph as the gold standard.

Total 22 children (13 male and 9 female) with short stature or precocious puberty were enrolled into this study. Their chronological age ranged from 4 to 14 years old. The children's left hand-wrist was scanned with the AVS by putting them into a water sink containing tape water. Coronal images of the left hand-wrist were reconstructed and compared with X-ray images.

The number of patients whose hand-wrist bones (except for the first metacarpal sesamoid bone and the secondary ossification center of the first metacarpal bone) identified by AVS image was not significantly different from that by X-ray image. In addition, the total number of observed bones in each patient were not significantly different between the two methods. The concordance rate (percentage of patients whose hand-wrist bone presented in both AVS image and X-ray image) was high and the inter-observer variance of BA was small.

The AVS method was highly correlated with the standard radiograph for children's bone age assessment with small inter-observer variability. This novel AVS method could be an alternative method in clinical practice for bone age assessment with higher safety and reliability.

Aggregation of fluidization media may appear at the dense phase region of the pant-leg fluidized bed near the incline walls. When the particles flow along the inclined wall, the friction and drag force will cause the particles to accumulate on the inclined wall, resulting in an uneven distribution of particles. The stagnant zones can be minimized by correctly arranging secondary air. Computational particle fluid dynamics (CPFD) method was used to simulate the gas-solid two-phase flow pattern in the dense phase region of pant-leg fluidized bed. Cold tests were performed on a benchtop pant-leg fluidized bed. A high speed imaging technology was used to monitor the flow pattern in the dense phase area, whereas the bubble size and residence time were compared to verify the accuracy of the simulation. The gas-solid flow patterns under various models were simulated. The influence of different secondary air velocities on the reduction of stagnant zone in the dense phase zone of the fluidized bed were predicted. The results indicated that the introduction of secondary air could effectively promote the mixing of particles, and weaken the accumulation of particles on the inclined wall surface. Moreover, secondary air can effectively promote the flow between the gas-solid two-phases and improve the combustion characteristics in the furnace.

The mucous membrane on the fish surface has excellent drag reduction performance. The mucous membrane can be regarded as the viscoelastic fluid, and a bionic friction drag reduction model is proposed with the consideration of a Carreau viscoelastic model-based mucus secretion process. Then, the drag reduction effect of the mucous membrane on the classical wall turbulence boundary layer is investigated by large-eddy simulations. Results show that the bionic mucous membrane is conducive to reducing the turbulence, and can achieve a drag reduction rate of about 14%. This study provides a hydrodynamics understanding of the drag reduction characteristics of the bionic mucous membrane.

To investigate effect of radiosensitization of [Ru(bpy)2(phen)]Cl2 complex on nasopharyngeal carcinoma cell line CNE1 and its mechanism.

Nasopharyngeal carcinoma cell line CNE1 in vitro culture was divided into control group, light irradiation group (4 Gy, 6 MV photonic line), simple metal ruthenium complex treatment group (Ru group, 100 μmol/L [Ru(bpy)2(phen)]Cl2) and metal ruthenium complex combined with radiotherapy group (Combined radiotherapy group, cells were irradiated with 4 Gy and 6 MV photons at 2 days after 100 μmol/L [Ru(bpy)2(phen)]Cl2).

Transcriptional level of P53 gene in combined radiotherapy group was higher than that in the other groups (P<0.001). Inhibition rate of combined radiotherapy group was higher than that of Ru group and irradiation group (P<0.001). Apoptotic rate was the highest (P<0.05) in the combined radiotherapy group, and irradiation group was higher than Ru group and control group (P<0.05). Survival rate of Ru group was lower than that of control group under the same radiation dose (P<0.05), and the radiotherapy sensitization ratio was 1.227 (Dq ratio).

[Ru(bpy)2(phen)]Cl2 increases the sensitivity of nasopharyngeal carcinoma cell line CNE1 to X-ray, which may be related to increase of P53 gene expression.

Many interval number ranking methods cannot representthe different attitudes of decision makers with different riskappetites. Therefore, interval numbers are expressed in the RectangularCoordinate System (RCS). After mining the interval numbers in the RCS,the Symmetry Axis Compensation Factor, which is known as (lambda),was introduced, and the Equivalent Function of the Goal Interval Number(GIN) was deduced. Thus, the interval number ranking method consideringsymmetry axis compensation was defined along with its applicationprocedures. Additionally, the feasibility and effectiveness of thismethod were verified through examples. This method is intuitive andsimple and can represent multiple attitudes of decision makers withdifferent risk appetites.