Study on Multi Objective Optimization Method and It Application in Aviation and Deceleration Device

Yu Guang-bin,Song Ye,Duan Yuan-wang,Zhao Xing-fu,Qu Zhigang,Sun Yong-guo 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.5

Crack Resistance and Strength Properties of Red Clay Modified with Lignocellulose and Guar gum

Hong-Yuan Fu,Guang-Tao Yu,Qian-Feng Gao,Ling Zeng,Shuo-Peng Cao 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.10

Desiccation cracking is a common problem of red clay under wet and dry conditions. The presence of cracks could reduce soil strength properties, which is the major reason for shallow failure of red clay slopes. This study aims to propose some additives to improve the crack resistance as well as the strength of red clay. To this end, three natural fibers and three natural gels were primarily selected to modify red clay. Desiccation crack tests were conducted to identify the best fiber and gel in terms of crack resistance. Then, direct shear tests and uniaxial tensile tests were performed on the soil specimens modified by the best fiber and gel to determine the optimal dosages regarding strength improvements. The results demonstrated that natural gels reduced the crack resistance of red clay, while natural fibers could enhance the crack resistance. Lignocellulose was the best additive in improving the crack resistance of red clay, and the modified effect was positively correlated with the fiber dosage. Adding 1.5% lignocellulose into red clay could reduce the crack rate from 2.19% to 0.30%, with a reduction of 0.86 times. The tensile strength, shear strength and its parameters of lignocellulose-modified red clay showed a trend of increasing first and then decreasing with increasing lignocellulose dosage. At the optimal lignocellulose dosage of 0.75%, the shear strength and tensile strength were increased by 44.63% and 18.21%, respectively. The strength of red clay modified by both lignocellulose and guar gum was positively correlated with the dosage of guar gum, and the desirable dosage of guar gum was 1.0%. In engineering practice, the wet red clay mixed with 0.75% lignocellulose and grass seeds can be employed as planting soil and is sprayed uniformly onto the slope surface after excavation using a spraying planting machine. To further improve the strength of the planting soil, 1.0% guar gum solution can be sprayed on the soil surface. The findings could provide useful guidance for the protection of red clay slopes.

Numerical model of the sorting of biological cells based on gravity-driven optoelectronic tweezers

Sheng Hu,Guang-Yuan Si,Rongrong Fu 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.5

Novel gravity-driven optoelectronic tweezers were developed for accurately sorting Jurkat and B16 cells. Synergistic integration of gravity and optoelectronic tweezers was developed as a new tool to provide unique features for sorting or separating mixtures of cells with different dielectric properties. This chip combined flexible programmable virtual electrodes with gravity-driven hydrodynamic flow motion instead of complicated fabrication of micro-pumps and valves. Accordingly, the structure of the microchannel was dimensional, based on a theoretical analysis and numerical model. Using both Jurkat and B16 cells, we obtained the dielectrophoretic separation frequency by using a single-shell model, reflecting their effective complex permittivity. Finally, the results of cellular trajectory analysis demonstrated that the gravity-driven optoelectronic tweezers were able to achieve sorting of Jurkat and B16 cells at a voltage of 11 V with 221.5 kHz, based on a molecular dynamics approach. To further enhance the separation accuracy and reduce the risk of lysing membranes, improved microchannels with two separated branches were designed and studied. Additionally, the shape of the virtual electrode was optimized to generate a greater electrical field magnitude than a rectangular electrode. Thus, the applied electrical voltage could be reduced to 7 V for cell sorting.

Quadratic Nonlinear Technologies for Femtosecond Lasers

Liejia Qian,Guang Xu,Hang Luo,Heyuan Zhu,Peng Yuan,Tao Wang,Xiquan Fu 한국물리학회 2005 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.46 No.2

Quadratic optical nonlinearity (2) can be exploited in femtosecond lasers and regarded as a significant new degree of freedom for the design of short-pulse sources. We will review our recent progress on developing nonlinear quadratic technologies for femtosecond lasers. Our nonlinear laser technology offers new properties for femtosecond lasers, including optical parametric amplifier with novel working regime, efficient second harmonic generation, and time telescope.

Utrecht Interstitial Applicator Shifts and DVH Parameter Changes in 3D CT-based HDR Brachytherapy of Cervical Cancer

Shi, Dan,He, Ming-Yuan,Zhao, Zhi-Peng,Wu, Ning,Zhao, Hong-Fu,Xu, Zhi-Jian,Cheng, Guang-Hui Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

Background: For brachytherapy of cervical cancer, applicator shifts can not be avoided. The present investigation concerned Utrecht interstitial applicator shifts and their effects on organ movement and DVH parameters during 3D CT-based HDR brachytherapy of cervical cancer. Materials and Methods: After the applicator being implanted, CT imaging was achieved for oncologist contouring CTVhr, CTVir, and OAR, including bladder, rectum, sigmoid colon and small intestines. After the treatment, CT imaging was repeated to determine applicator shifts and OARs movements. Two CT images were matched by pelvic structures. In both imaging results, we defined the tandem by the tip and the base as the marker point, and evaluated applicator shift, including X, Y and Z. Based on the repeated CT imaging, oncologist contoured the target volume and OARs again. We combined the treatment plan with the repeated CT imaging and evaluated the change range for the doses of CTVhr D90, D2cc of OARs. Results: The average applicator shift was -0.16 mm to 0.10 mm for X, 1.49 mm to 2.14 mm for Y, and 1.9 mm to 2.3 mm for Z. The change of average physical doses and EQD2 values in Gy${\alpha}/{\beta}$ range for CTVhr D90 decreased by 2.55 % and 3.5 %, bladder D2cc decreased by 5.94 % and 8.77 %, rectum D2cc decreased by 2.94 % and 4 %, sigmoid colon D2cc decreased by 3.38 % and 3.72 %, and small intestines D2cc increased by 3.72 % and 10.94 %. Conclusions: Applicator shifts and DVH parameter changes induced the total dose inaccurately and could not be ignored. The doses of target volume and OARs varied inevitably.

Impact of Global and Gene-Specific DNA Methylation in de Novo or Relapsed Acute Myeloid Leukemia Patients Treated with Decitabine

Zhang, Li-Ying,Yuan, You-Qing,Zhou, Dong-Ming,Wang, Zi-Yan,Ju, Song-Guang,Sun, Yu,Li, Jun,Fu, Jin-Xiang Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.1

In this investigation, global DNA methylation patterns and the specific methylation status of 5 genes were studied in DNA from peripheral blood (PB) and impact on progression free survival (PFS) and overall-survival (OS) in patients with de novo or relapsed acute myeloid leukemia (AML) treated with decitabine-based regimens waas assessed. DNA was isolated from PB samples at the time of -1, 1, and 7 days of chemotherapy. Global methylation was determined by ELISA, and the CpG island DNA methylation profile of 5 genes using a DNA methylation PCR system. Our data demonstrated that patients with a high level of 5-mC had a poor prognosis after demethylation therapy and those who have low levels of 5-mC in PB achieved higher CR and better SO, but there was no significant correlation found between the 5-mC levels and other clinical features before treatment except the disease status. Higher methylation status of Sox2 and Oct4 genes was associated with differential response to demethylation therapy. A relatively low methylation percentage in one or both of these two genes was also associated with longer OS after decitabine based chemotherapy. We also suggest that global DNA and Oct-4/Sox2 methylation might impact on the pathogenesis of leukemia and play an important role in the initiation and progression. Moreover, dynamic analysis of 5-mC and Oct-4/Sox2 in peripheral blood nucleated cells of leukemia patients may provide clues to important molecular diagnostic and prognostic targets.

Study on rectangular concrete-filled steel tubes with unequal wall thickness

Yang Zhang,Chen-Jiang Yu,Guang-Yuan Fu,Bing Chen,She-Xu Zhao,Si-Ping Li 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.22 No.5

Rectangular concrete-filled steel tubular columns with unequal wall thickness were investigated in the paper. The physical centroid, the centroidal principal axes of inertia, and the section core were given. The generalized bending formula and the generalized eccentric compression formula were deduced, and the equation of the neutral axis was also provided. The two rectangular concrete-filled steel tubular stub specimens subjected to the compression load on the physical centroid and the geometric centroid respectively were tested to verify the theoretical formulas.

Experimental behavior of circular flyash-concrete-filled steel tubular stub columns

Si-Ping Li,Yang Zhang,Guang-Yuan Fu,Chen-Jiang Yu,Bing Chen,She-Xu Zhao 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.22 No.4

The paper presents an experimental study of the structural behavior of circular flyash-concrete-filled steel tubular stub columns under axial compressive loads. In this study, 90% and 100% by weight of the cement in the concrete core was replaced with flyash. Twenty-seven specimens were tested to study the influence of flyash content, wall thickness of the steel tube, and curing age on the ultimate capacity and confinement effect. The experimental results were compared with the design values calculated using AISC-LRFD (1999), ACI (1999), AIJ (1997) and Eurocode 4 (1994). From the experimental study, it was determined that the confinement effect of circular steel tubes filled with high content flyash concrete was better than that of specimens filled with ordinary Portland cement concrete. The 5.88-mm-thick steel tube filled with 100% flyash concrete was equivalent in strength to a steel tube filled with C30 concrete at 28 days.

Electronic Structure, Phase Transition, and Elastic Properties of ScC under High Pressure

Yu-Xin Zhao,Jun Zhu,Yan-Jun Hao,Zi-Yuan Li,Long-Qing Chen,Guang-Fu Ji 한국물리학회 2015 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.67 No.12

The structural properties and the phase transition for scandium carbide (ScC) have been studied in NaCl (B1), CsCl (B2), ZB (B3), WZ (B4), NiAs (B81), WC (Bh), and Pmmn structures by using the pseudopotential plane-wave method in the framework of the density functional theory. Our theoretical results show that the most stable structure is the B1 phase, contrary to the result of Rahim et al. The phase transitions B1 ! Pmmn and Pmmn ! B2 are predicted at 83.7 and 109.7 GPa, respectively. At the same time, we find that the B3, B4, B81, and Bh phases are not stable over the whole pressure range considered. In particular, the elastic constants of Pmmn-ScC under high pressure are obtained successfully. The effects of pressure on the elastic properties of B1-ScC and Pmmn-ScC are also predicted. The Debye temperatures and the sound velocities of these two structures are estimated from the elastic constants, and by analyzing G/B, the brittle-ductile behavior of ScC is assessed. In addition, the density of states of B1-ScC at high pressures is also discussed.