Experimental study on the tension of cables and motion of tunnel element for an immersed tunnel element under wind, current and wave

Wu Hao,Rheem Chang-Kyu,Chen Wei,Xu Shuangxi,Wu Weiguo 대한조선학회 2021 International Journal of Naval Architecture and Oc Vol.13 No.1

The tension of cables and motion response significantly affect safety of an immersed tunnel element in the immersion process. To investigate those, a hydrodynamic scale-model test was carried out and the model experiments was conducted under wind, current and wave loads simultaneously. The immersion standby (the process that the position of the immersed tunnel element should be located before the immersion process) and immersion process conditions have been conducted and illustrated. At the immersion standby conditions, the maximum force of the cables and motion is much larger at the side of incoming wind, wave and current, the maximum force of Element-6 (6 cables directly tie on the element) is larger than for Pontoon-8 (8 cables tie on pontoon of the element), and the flexible connection can reduce the maximum force of the mooring cables and motion of element (i.e. sway is expecting to decrease approximate 40%). The maximum force of the mooring cables increases with the increase of current speed, wave height, and water depth. The motion of immersed tunnel element increases with increase of wave height and water depth, and the current speed had little effect on it. At the immersion process condition, the maximum force of the cables decrease with the increase of immersion depth, and dramatically increase with the increase of wave height (i.e. the tension of cable F4 of pontoons at wave height of 1.5 m (83.3t) is approximately four times that at wave height of 0.8 m). The current speed has no much effect on the maximum force of the cables. The weight has little effect on the maximum force of the mooring cables, and the maximum force of hoisting cables increase with the increase of weight. The maximum value of six-freedom motion amplitude of the immersed tunnel element decreases with the increase of immersion depth, increase with the increase of current speed and wave height (i.e. the roll motion at wave height of 1.5 m is two times that at wave height of 0.8 m). The weight has little effect on the maximum motion amplitude of the immersed tunnel element. The results are significant for the immersion safety of element in engineering practical construction process.

The 16-year experience in treating low-risk gestational trophoblastic neoplasia patients with failed primary methotrexate chemotherapy

Xiaodong Wu,Jiale Qin,Tao Shen,Weidong Fei,Lili Chen,Xing Xie,Weiguo Lu 대한부인종양학회 2020 Journal of Gynecologic Oncology Vol.31 No.4

Objective: To assess the outcomes and toxic effects of 5-day actinomycin D (Act-D) salvagetherapy and to explore the predictors of Act-D resistance in patients with low-risk gestationaltrophoblastic neoplasia (GTN)who failed 5-day methotrexate (MTX) chemotherapy. Methods: This retrospective study analyzed patients with low-risk GTN administered Act-Dsalvage therapy after failing MTX chemotherapy at Women's Hospital, School of MedicineZhejiang University between January 2000 and December 2015. The clinical parameters ofthese patients were collected and analyzed. Results: The final analysis included 89 cases. Of these, 73 cases (82.02%) responded tosalvage Act-D. The remaining 16 resistant cases were switched to etoposide, MTX, Act-D/cyclophosphamide, and vincristine chemotherapy and achieved complete remission. Serumhuman chorionic gonadotrophin levels before Act-D salvage therapy (hCGAct-D)in the Act-D resistant cases were significantly higher than those in the Act-D responders (median 605 vs. 103 IU/L, p=0.009). However, the range of hCGAct-D values in Act-D responders was wider thanthat in Act-D-resistant cases (5.76–16,664 IU/L vs. 11.43–6,732 IU/L). Thus, assigning a generalcut-off value was difficult considering the individual setting. Except for 2 cases requiring othersalvage regimens due to Act-D toxicity, 97.80% of cases (89/91) tolerated the toxicity. During atleast 1-year follow-up, the survival rate was 100.00% and no case developed recurrence. Conclusion: Based on the good therapeutic effect and tolerable toxicity, we recommendAct-D salvage therapy for all patients with low-risk GTN who fail primary MTX chemotherapy. The higher serum hCG levels before Act-D salvage therapy may be associated with resistanceto this treatment.

Comparison of the Distribution Pattern of 21-Gene Recurrence Score between Mucinous Breast Cancer and Infiltrating Ductal Carcinoma in Chinese Population: A Retrospective Single-Center Study

Jiayi Wu,Shuning Ding,Linling Yin,Xiaochun Fei,Caijin Lin,Lisa Andriani,Chihwan Goh,Jiahui Huang,Jin Hong,Weiqi Gao,Siji Zhu,Hui Wang,Ou Huang,Xiaosong Chen,Jianrong He,Yafen Li,Kunwei Shen,Weiguo Che 대한암학회 2020 Cancer Research and Treatment Vol.52 No.3

Purpose This retrospective study aimed to evaluate the distribution pattern and prognostic value of 21-gene recurrence score (RS) in Chinese patients with mucinous breast cancer (MC) and compared with infiltrating ductal carcinoma (IDC). Materials and Methods Patients diagnosed with MC or IDC from January 2010 to January 2017 were retrospectively recruited. Reverse transcriptase–polymerase chain reaction assay of 21 genes was conducted to calculate the RS. Univariate and multivariate analyses were performed to assess the association between RS and clinicopathological factors. Survival outcomes including disease-free survival (DFS) and overall survival (OS) were estimated by Kaplan-Meier method and compared by log-rank test. Results The MC cohort included 128 patients and the IDC cohort included 707 patients. The proportions of patients with a low (RS < 18), intermediate (18-30), or high risk (RS > 30) were 32.0%, 48.4%, and 19.5% in MC cohort, and 26.9%, 46.8% and 26.3% in IDC cohort. The distribution of RS varied significantly according to different Ki-67 index and molecular subtype in both cohorts. Moreover, the receipt of chemotherapy was associated with RS in both cohorts. Among patients with MC, tumor stage was related to the DFS (p=0.040). No significant differences in DFS and OS were found among MC patients in different RS risk groups (OS, p=0.695; DFS, p=0.926). Conclusion RS was significantly related to Ki-67 index and molecular subtypes in MC patients, which is similar in IDC patients. However, RS was not able to predict DFS and OS in patients with MC.

CeO2-La2O3/ZSM-5 sorbents for high-temperature H2S removal

Jiang Wu,Weiguo Zhou,Dongjing Liu 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.6

Performance of CeO2-La2O3/ZSM-5 sorbents for sulfur removal was examined at temperature ranging from 500 oC to 700 oC. The sulfur capacity of 5Ce5La/ZSM-5 was much bigger than that of CeO2/ZSM-5. H2 had a negative impact on the sulfidation; however, CO had little influence on sulfur removal. The characterization results showed that CeO2 and La2O3 were well dispersed on ZSM-5 because of the intimate admixing of La2O3 and CeO2, the major sulfidation products were Ce2O2S and La2O2S, the XRD and SEM results revealed that ZSM-5 structure could remain intact during preparation and sulfidation process, the H2-TPR showed that the reducibility of CeO2 can be remarkably enhanced by addition of La.

Investigation on Preparation of Ge Quantum Dots in $SiO_2$ Thin Films

Chen, Jing,Wu, Xuemei,Jin, Zongming,Yao, Weiguo The Korean Vacuum Society 1998 Applied Science and Convergence Technology Vol.7 No.1

Ge quantum dots in $SiO_2$ thin films were prepared by r.f. magnetron co-sputtering using a Ge, $SiO_2$ composite target. The size of quantum dots was modulated by controlling of substrate temperature during depositing and annealing of samples deposited at certain substrate temperature. A series of work was done on the influence of preparing parameters on the growth of quantum dots, and a discussion on the formation and growth of quantum dots under different preparation parameters is given.

Robust Path Following Controller for Unmanned Aerial Vehicle Based on Carrot Chasing Guidance Law Using Dynamic Inversion

Ehab Safwat,Weiguo Zhang,Mei Wu,Yongxi Lyu,Qianlei Jia 제어로봇시스템학회 2018 제어로봇시스템학회 국제학술대회 논문집 Vol.2018 No.10

This paper focuses on autonomous path-following flight under uncertainty and external disturbances. Integrated UAV waypoints guidance scheme based on carrot chasing guidance law is presented. In order to follow a desired path a Virtual Track Point (VTP) is introduced on the path and make the UAV chase it. The UAV updates its heading direction toward the VTP. As time progresses, the UAV will move toward the path and asymptotically follow the path. Nonlinear Dynamic Inversion (NDI) awards the flight control system researchers a straight forward method of deriving control laws for nonlinear systems. The control inputs are used to cancel unwanted terms in the equations of motion using negative feedback of these terms. The two-timescale assumption that separates the fast dynamics which are the three angular rates of the aircraft from the slow dynamics which include the angle of attack, side-slip angle, and bank angle is adopted. NDI control law is designed for the fast variables using the deflection of aerodynamic control surfaces as inputs. Next, NDI is applied to the control of the slow states using the outputs of the fast loop as inputs. Simulation results for the nonlinear flight control system are given to illustrate the effectiveness of the technique. The validation of the designed flight system controller is demonstrated through real flight test.

The Effect of Na0.44MnO2 Formation in Na+-Modified Spinel LiMn2O4

Lilong Xiong,Youlong Xu,Weiguo Wu,Pei Lei,Tao Tao,Xin Dong 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.4

Na0.44MnO2 impure phase is formed during the synthetic process of Na+-modified spinel LiMn2O4 by solid state reaction which is confirmed by x-ray diffraction analysis. Scanning electron microscopy, transmission electron microscopy and galvanostatic charge-discharge measurements are carried out to investigate the effect of the formation of Na0.44MnO2 impurity on the morphology and electrochemical properties of the spinel material. The results show that the spinel material with impure phase exhibits improved cyclability compared to that of the pristine LiMn2O4. The improved electrochemical performance is mainly ascribed to the improved crystallinity of the spinel particles, enhanced stability of the spinel structure and good electronic conductivity of the composite.

Longitudinal Dynamic End Effect of Single-Sided Linear Induction Motor for Medium–Low Speed Maglev

Wang Ying,Liu Xuelong,Lu Weiguo,Wen Tianqi,Yu Fan,Wu Qian 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.4

The Short Primary Single-sided Linear Induction Motor (SLIM) applied in medium–low maglev vehicle has end eff ect that will cause a signifi cant reduction of train thrust. This paper analyzes the relationship between the Longitudinal Dynamic End Eff ect (LDEE) and the speed of SLIM. It is concluded that LDEE increases with the motor speed. The LDEE at motor’s exit area is called tailing eff ect. We take advantage of the tailing eff ect between adjacent SLIMs to make the air-gap magnetic fi eld of these motors continuous by adjusting their intervals and excitation phase diff erence. The several SLIM on the same side of the vehicle is equivalent to a “whole motor” with overall one entry area and one exit area. This method can reduce the resistance of the whole vehicle running at high speed, which can provide a new solution for the design of high-speed SLIM applied in Maglev

Vibro-acoustic modelling of immersed cylindrical shells with variable thickness

Wang, Xianzhong,Lin, Hongzhou,Zhu, Yue,Wu, Weiguo The Society of Naval Architects of Korea 2020 International Journal of Naval Architecture and Oc Vol.12 No.-

Based on the Precise Transfer Matrix Method (PTMM), the dynamic model is constructed to observe the vibration behaviour of cylindrical shells with variable thickness by solving a set of first-order differential equations. The free vibration of stiffened cylindrical shells with variable thickness can be obtained to compare with the exact solution and FEM results. The reliability of the present method of free vibration is well proved. Furthermore, the effect of thickness on the vibration responses of the cylindrical shell is also discussed. The acoustic response of immersed cylindrical shells is analyzed by a Pluralized Wave Superposition Method (PWSM). The sound pressure coefficient can be gained by collocating points along the meridian line to satisfy the Neumann boundary condition. The mode convergence analysis of the cylindrical shell is carried out to guarantee calculation precision. Also, the reliability of the present method on sound radiation is verified by comparing with experimental results and numerical results.

Carbon Nanotubes-Supported Well-Dispersed Pd Nanoparticles for the Efficiently Selective Hydrogenation of Benzoic Acid to Synthesize Cyclohexane Carboxylic Acid

Yin Hu,Wei Chen,Qi Wu,Xin Xie,Weiguo Song 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.1

Pd and carbon nanotube (CNT) composites were prepared by well-dispersed deposition of Pd nanoparticles on commercial CNT, and applied to the selective hydrogenation of benzoic acid (BA) to synthesize cyclohexane carboxylic acid (CCA). The catalysts and the hydrogenation products were analyzed by XRD, TEM, TG, FTIR, UV-Vis absorption, GC and GC-MS, respectively. Hydrogenation process was also optimized through varying the reaction parameters. The results demonstrate that Pd/CNT catalysts possess the highest hydrogenation efficiency, give the full conversion of BA and 100.0% selectivity towards CCA at the optimal hydrogenation conditions, by comparing with some commercial hydrogenation catalysts and Pd/C catalysts with commercial carbonaceous supports. The excellent hydrogenation performance of Pd/CNT is attributed to the stable crystalline CNT support and the high dispersion of Pd nanoparticles. In addition, the protic solvent is also beneficial to lower the activation energy barrier of BA hydrogenation, and further to improve the hydrogenation rate. This work implies that CNT can be potentially chosen as an effective carbonaceous support to prepare Pd/C catalyst with an outstanding performance of BA selective hydrogenation.