Key Assumption to Evaluate the Mechanical Performance of Widened Voided-slab Bridge Due to Foundation Settlement

Wenqing Wu,Hongwei Shan,Song Yang,Zhangxiang Tang 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.4

In concrete bridge widening projects, it is a common practice to provide a monolithic connection between the existing and newdecks by casting an in situ concrete stitching slab. As a result, the differential foundation settlement between the two decks has aconsiderable effect on the concrete stitching slab and the widened bridge. The widened bridge noted as multi-girder bridge is asimple-supported, precast, voided-slab bridge, located on the Beijing–Shanghai Expressway in east of China. When using a grillageFinite Element Model (FEM) to model the mechanical behavior of the multi-girder bridge after it has been widened, the generalapproach to account for the effect of differential foundation settlement is to load a calculated forced vertical displacement to thebearing of each precast slab of the new bridge. However, there is no suitable mathematical model to be used for calculating the forceddisplacement for all new slab beams, which requires the ability to describe the transverse distribution mode of these forceddisplacement under a given differential foundation settlement. Under this background, an experimental study and finite elementanalysis are conducted to find this suitable mathematical model in this paper. Based on a comprehensive research results, a quadraticcurve model was considered to be a suitable mathematical model to meet the design need of such type of widened multi-girderbridge, and its quadratic equation was also derived in the paper. This finding is the key assumption for accurately analyzing themechanical behavior of a widened multi-girder bridge, with a grillage finite element model.

New Hanger Design Approach of Tied-Arch Bridge to Enhance Its Robustness

Wenqing Wu,Hao Wang,Yan-Jie Zhu,Jiangyu Yu,Hao Zhao,Hui Zhang 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.11

As the crucial components among the tied-arch bridge, the local failure of hangers may trigger a progressive collapse through the entire tied-arch bridge. However, the current design guidance as regards hangers still lacks consideration of structure robustness under an extreme hazard. To improve the structural robustness of tied-arch bridge under extreme conditions, a new hanger design method is proposed, which is termed as asymmetric parallel double-hanger system. Based on Miner’s linear cumulative damage law, an analysis on the fatigue life of the double-hanger system was conducted to verify the feasibility of the proposal, and then a dynamic time-history analysis was employed to simulate the transitory fracture impact due to one or more hangers fracturing. According to the simulation results, the structural robustness is greatly enhanced with asymmetric parallel-double hanger system design, when compared with single hanger system design. When one or more hangers reveal local damage, it will not trigger a progress failure to the whole structure in particular. Several practical suggestions of bridge system’s load-carrying capacity are also put forward for the future arch bridge design at the end of this paper.

Properties of Aspergillar Xylanase and the Effects of Xylanase Supplementation in Wheat-based Diets on Growth Performance and the Blood Biochemical Values in Broilers

Wu, Yubo,Lai, Changhua,Qiao, Shiyan,Gong, Limin,Lu, Wenqing,Li, Defa Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.1

Three experiments were conducted to study the property of xylanase and the effects of xylanase in wheat-based diets on growth performance of broilers, respectively. Experiment 1 was performed in vitro to evaluate the effect of different pH and temperature on xylanase activity, and to evaluate the enzymic stability under different conditions. The results indicated that the optimum temperature and pH for xylanase activity were $50^{\circ}C$ and 4.5, respectively. The activity of enzyme solution was reduced rapidly after the treatment of water bath above $60^{\circ}C$ for 10 min. The enzyme was relatively stable at pH 3.5 to 8.0 and deteriorated when incubated at pH below 3.5. In Experiment 2, a total of 378 d-old male Arbor Acres broilers were randomly distributed to 7 different treatments with 6 replicates (9 birds) in each treatment. The treatments were as follows: (1) corn based diet (CS), (2) wheat based diet (WS), (3) WS+ 0.05% xylanase, (4) WS+0.15% xylanase, (5) WS+0.25% xylanase, (6) WS+0.35% xylanase, (7) WS+0.45% xylanase. The results showed that the body weight and feed/gain ratio of the broilers fed wheat-based diets have been significantly improved (p<0.05) compared to that fed corn-based diet in the first 3 wk. With regard to the wheat-based diets, the xylanase supplementation had a tendency to improve the growth performance in first 3 wk. After 3 wk, no significant difference (p>0.05) was found among all these different treatments. The supplementation of xylanase and the type of diets did not affect the feed intake but increased the concentration of triglyceride in serum. In Experiment 3, a total of 360 d-old male Arbor Acres broilers were assigned to 30 groups with 12 birds in each group randomly. These groups were then randomly distributed to 5 different treatments with 6 replicates within each treatment. The broilers of each treatment were fed one of the diets as follows: (1) Corn based diet, (2) White wheat based diet (WW) (3) White wheat based diet+0.25% xylanase, (4) Red wheat based diet, (5) Red wheat based diet+0.25% xylanase. The results showed that the body weight and feed/gain ratio had been significantly improved (p<0.05) by xylanase supplementation in the first 2 or 3 wk. The effect of xylanase in red wheat diet is a little higher than that used in white wheat diet. From the results of the present experiments, it can be concluded that the supplementation of Aspergillar xylanase can improve the performance of the broilers fed the wheat-based diet.

Practical Tracking Control of a Class of Uncertain Surface Vessels Under Weak Assumptions on Uncertainties and Reference Trajectories

Wenqing Xu,Jian Li,Zhaojing Wu 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.3

This paper is devoted to the tracking control of a class of uncertain surface vessels. The main contributions focus on the considerable relaxation of the severe restrictions on system uncertainties and reference trajectory in the related literature. Specifically, all the system parameters are unknown and the disturbance is not necessarily to be differentiable in the paper, but either the unknown parameters or the disturbance is considered but the other one is excluded in the related literature, or both of them are considered but the disturbance must be continuously differentiable. Moreover, the reference trajectories in the related literature must be at least twice continuously differentiable and their time derivatives must be known for feedback, which are generalized to a more broad class of ones in the paper that are only once continuously differentiable without the measurements of their time derivatives. To solve the control problem, a novel practical tracking control scheme is presented by using backstepping scheme and adaptive technique, and in turn to derive an adaptive state-feedback controller which guarantees that all the states of the resulting closed-loop system are bounded while the tracking error arrives at and then stays within an arbitrary neighborhood of the origin. Finally, simulation is provided to validate the effectiveness of the proposed theoretical results.

Clinical Features, Treatments, and Prognosis of Intramedullary Spinal Cord Metastases From Lung Cancer: A Case Series and Systematic Review

Liang Wu,Li’ao Wang,Jun Yang,Wenqing Jia,Yulun Xu 대한척추신경외과학회 2022 Neurospine Vol.19 No.1

Objective: Intramedullary spinal cord metastasis from lung cancer (ISCM-LC) are increasing in prevalence. We aim to investigate its clinical features, treatments and prognosis. Methods: We reported 6 ISCM-LC cases and conducted a systematic review. Descriptive summarization, survival analysis, and multivariate Cox regression analysis were performed to comprehensively study the disease. Results: All 6 patients had surgery. One used chemotherapy and the other had targeted drugs. Two patients died of ISCM-LC, 1 died of pulmonary embolism, 1 was alive, and 2 were lost to follow-up. We identified 197 ISCM-LC cases in literature with a mean age of 58 years and male preponderance. Small cell lung cancer accounted for 39.1%. The median interval from lung cancer to ISCM-LC was 7 months. Limb weakness was the most common symptom, and 45% cases progressed rapidly. Concomitant brain, leptomeningeal, and vertebral metastasis occurred to 55.8%, 20%, and 19.5%, respectively. Peritumoral edema appeared in 83.3%. Through survival analysis, we found sex, extraspinal metastasis, pathology, and improved symptoms affected the overall survival. Additionally, gross total resection (GTR) shared similar effectiveness with non-GTR, and other treatments following surgery hardly added extra effect. Surgery, improved symptoms, and sex were 3 independent prognostic factors after adjusting for confounding. The estimated median survival time was 5 months. Conclusion: The overall survival of ISCM-LC remains poor. Surgery is an independent protective factor for survival. Surgery should be considered once tolerated, and GTR might not be necessary. In addition, female patients with improved symptoms after intervention might have better overall survival.

Optical Image Encryption Technique Based on Hybrid-pattern Phase Keys

Sun, Wenqing,Wang, Lei,Wang, Jun,Li, Hua,Wu, Quanying Optical Society of Korea 2018 Current Optics and Photonics Vol.2 No.6

We propose an implementation scheme for an optical encryption system with hybrid-pattern random keys. In the encryption process, a pair of random phase keys composed of a white-noise phase key and a structured phase key are positioned in the input plane and Fourier-spectrum plane respectively. The output image is recoverable by digital reconstruction, using the conjugate of the encryption key in the Fourier-spectrum plane. We discuss the system encryption performance when different combinations of phase-key pairs are used. To measure the effectiveness of the proposed method, we calculate the statistical indicators between original and encrypted images. The results are compared to those generated from a classical double random phase encoding. Computer simulations are presented to show the validity of the method.

The construction of second generation wavelet-based multivariable finite elements for multiscale analysis of beam problems

Wang, Youming,Wu, Qing,Wang, Wenqing Techno-Press 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.50 No.5

A design method of second generation wavelet (SGW)-based multivariable finite elements is proposed for static and vibration beam analysis. An important property of SGWs is that they can be custom designed by selecting appropriate lifting coefficients depending on the application. The SGW-based multivariable finite element equations of static and vibration analysis of beam problems with two and three kinds of variables are derived based on the generalized variational principles. Compared to classical finite element method (FEM), the second generation wavelet-based multivariable finite element method (SGW-MFEM) combines the advantages of high approximation performance of the SGW method and independent solution of field functions of the MFEM. A multiscale algorithm for SGW-MFEM is presented to solve structural engineering problems. Numerical examples demonstrate the proposed method is a flexible and accurate method in static and vibration beam analysis.

The construction of second generation wavelet-based multivariable finite elements for multiscale analysis of beam problems

Youming Wang,Qing Wu,Wenqing Wang 국제구조공학회 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.50 No.5

A design method of second generation wavelet (SGW)-based multivariable finite elements is proposed for static and vibration beam analysis. An important property of SGWs is that they can be custom designed by selecting appropriate lifting coefficients depending on the application. The SGW-based multivariable finite element equations of static and vibration analysis of beam problems with two and three kinds of variables are derived based on the generalized variational principles. Compared to classical finiteelement method (FEM), the second generation wavelet-based multivariable finite element method (SGWMFEM) combines the advantages of high approximation performance of the SGW method and independent solution of field functions of the MFEM. A multiscale algorithm for SGW-MFEM is presented to solve structural engineering problems. Numerical examples demonstrate the proposed method is a flexible and accurate method in static and vibration beam analysis.

Array Organization and Data Management Exploration in Racetrack Memory

Zhenyu Sun,Xiuyuan Bi,Wenqing Wu,Sungjoo Yoo,Hai Helen Li IEEE 2016 IEEE Transactions on Computers Vol. No.

<P>As the descendant of spin-transfer random access memory (STT-RAM), racetrack memory technology saves data in magnetic domains along nanoscopic wires. Such a unique structure can achieve unprecedentedly high storage density meanwhile inheriting the promising features of STT-RAM, such as fast access speed, non-volatility, zero standby power, hardness to soft errors, and compatibility with CMOS technology. Moreover, the recent success in planar racetrack nanowire promised its fabrication feasibility and continuous scalability. In this paper, we investigate the design and optimization of racetrack memory as last-level cache by embracing design considerations across multiple abstraction layers, including the cell design, the array structure, the architecture organization, and the data management. The cross-layer optimization makes racetrack memory based last-level cache achieve 6.4 x reduction in area, 25 percent enhancement in system performance, and 62 percent saving in energy consumption, compared to STT-RAM cache design. Its benefit over SRAM technology is even more significant.</P>

The Chitin-Induced Chimeric LYK4-ER Gene Improves the Heat Tolerance of Arabidopsis at the Seedling Stage

Linxiao Chen,Wei Xia,Jinxing Song,Mengqi Wu,Zhizhen Xu,Xiangyang Hu,Wenqing Zhang 한국식물학회 2020 Journal of Plant Biology Vol.63 No.4

Due to global warming, high temperature has become the main abiotic stress affecting plant growth worldwide. LysM-containing receptor-like kinase 4 (LYK4) is the receptor for chitin, and ERECTA(ER) is a key factor in plant tolerance to high temperature. In this study, we constructed a chitin-induced chimeric LYK4-ER gene, in which the extracellular region and transmembrane domain of the LYK4 gene are fused with the intracellular region of the ER gene. Colony PCR, RT-PCR and western blot analyses of LYK4-ER transcription in plants, confirmed that the LYK4-ER gene was successfully constructed and transferred into Arabidopsis. The LYK4-ER gene localized to the cytomembrane and cytoplasm in vivo because of the binding properties of the transmembrane domain of the LYK4-ER gene to the cell membrane. The transgenic plants showed a higher germination rate and germination index as well as a shorter mean germination time than the wild-type plants, indicating that the LYK4-ER gene increases the heat tolerance of Arabidopsis. The lower H2O2 content and relative electrolytic leakage of the transgenic plants showed that the status of these plants under heat stress was improved. UPLC-MS/MS was used to analyze the phytohormones content, which suggested that the transgenic plants exhibited improved heat tolerance through jasmonic acid signal transduction pathways.