Experimental Study on Bond Behavior between Section Steel and RAC under Full Replacement Ratio

Chao Liu,Ziyu Fan,Xiaona Chen,Chao Zhu,Haiyang Wang,Guoliang Bai 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.3

Nine specimens of steel reinforced recycled concrete are designed to explore the effect of four factors as the cover thickness of section steel, the embedded length of section steel, the recycled aggregate concrete strength, and the lateral stirrup ratio on bond slip between section steel and recycled aggregate concrete. The test results show that the failure modes of recycled aggregate concrete are as similar as normal concrete; three formulas are proposed for the bond stress between section steel and recycled aggregate concrete, which are fitting well. The mathematical model of bond stress-slip is established through analysis, and the predicted curve is close to the test curve. The research results provide the basis for the numerical simulation analysis of the bond slip for the recycled aggregate concrete under the full replacement ratio.

Epithelial-mesenchymal Transition and Its Role in the Pathogenesis of Colorectal Cancer

Zhu, Qing-Chao,Gao, Ren-Yuan,Wu, Wen,Qin, Huan-Long Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.5

Epithelial-to-mesenchymal transition (EMT) is a collection of events that allows the conversion of adherent epithelial cells, tightly bound to each other within an organized tissue, into independent fibroblastic cells possessing migratory properties and the ability to invade the extracellular matrix. EMT contributes to the complex architecture of the embryo by permitting the progression of embryogenesis from a simple single-cell layer epithelium to a complex three-dimensional organism composed of both epithelial and mesenchymal cells. However, in most tissues EMT is a developmentally restricted process and fully differentiated epithelia typically maintain their epithelial phenotype. Recently, elements of EMT, specially the loss of epithelial markers and the gain of mesenchymal markers, have been observed in pathological states, including epithelial cancers. Increasing evidence has confirmed its presence in human colon during colorectal carcinogenesis. In general, chronic inflammation is considered to be one of the causes of many human cancers including colorectal cancer(CRC). Accordingly, epidemiologic and clinical studies indicate that patients affected by ulcerative colitis and Crohn's disease, the two major forms of inflammatory bowel disease, have an increased risk of developing CRC. A large body of evidence supports roles for the SMAD/STAT3 signaling pathway, the NF-kB pathway, the Ras-mitogenactivated protein kinase/Snail/Slug and microRNAs in the development of colorectal cancers via epithelial-tomesenchymal transition. Thus, EMT appears to be closely involved in the pathogenesis of colorectal cancer, and analysis refered to it can yield novel targets for therapy.

Study on Calculation Method of Long Term Deformation of RAC Beam based on Creep Adjustment Coefficient

Chao Liu,Zhenyuan Lv,Chao Zhu,Guoliang Bai,Yu Zhang 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.1

The creep shrinkage of concrete is an important factor in the long-term deformation of concrete structures. It is also a key link for solving long-term deformation calculation accuracy and complex calculation forms. In this paper, a 1200-day long-term deformation test was conducted on beams with 0%, 50%, and 100% substitution ratios of recycled coarse aggregate. Meanwhile, based on the principle of virtual work, the creep coefficient of recycled concrete is introduced into the calculation of additional curvature of the beam section, and the formula for calculating the long-term deformation of recycled concrete is established. According to the size of recycled coarse aggregate, through the calculation of creep and shrinkage of concrete, the regeneration adjustment coefficient of concrete creep and shrinkage, the calculation results into three typical model of ordinary concrete creep and shrinkage, creep and shrinkage of concrete and regeneration model of deformation calculation of long period, the calculated and experimental results agree well; based on this, the deflection increase coefficient is proposed, which simplifies the long-term calculation formula. It not only can meet the calculation accuracy requirements, but also can be easily adapted to engineering promotion.

Developing a Dynamic Materialized View Index for Efficiently Discovering Usable Views for Progressive Queries

Zhu, Chao,Zhu, Qiang,Zuzarte, Calisto,Ma, Wenbin Korea Information Processing Society 2013 Journal of information processing systems Vol.9 No.4

Numerous data intensive applications demand the efficient processing of a new type of query, which is called a progressive query (PQ). A PQ consists of a set of unpredictable but inter-related step-queries (SQ) that are specified by its user in a sequence of steps. A conventional DBMS was not designed to efficiently process such PQs. In our earlier work, we introduced a materialized view based approach for efficiently processing PQs, where the focus was on selecting promising views for materialization. The problem of how to efficiently find usable views from the materialized set in order to answer the SQs for a PQ remains open. In this paper, we present a new index technique, called the Dynamic Materialized View Index (DMVI), to rapidly discover usable views for answering a given SQ. The structure of the proposed index is a special ordered tree where the SQ domain tables are used as search keys and some bitmaps are kept at the leaf nodes for refined filtering. A two-level priority rule is adopted to order domain tables in the tree, which facilitates the efficient maintenance of the tree by taking into account the dynamic characteristics of various types of materialized views for PQs. The bitmap encoding methods and the strategies/algorithms to construct, search, and maintain the DMVI are suggested. The extensive experimental results demonstrate that our index technique is quite promising in improving the performance of the materialized view based query processing approach for PQs.

Developing a Dynamic Materialized View Index for Efficiently Discovering Usable Views for Progressive Queries

( Chao Zhu ),( Qiang Zhu ),( Calisto Zuzarte ),( Wenbin Ma ) 한국정보처리학회 2013 Journal of information processing systems Vol.9 No.4

Numerous data intensive applications demand the efficient processing of a new type of query, which is called a progressive query (PQ). A PQ consists of a set of unpredictable but inter-related step-queries (SQ) that are specified by its user in a sequence of steps. A conventional DBMS was not designed to efficiently process such PQs. In our earlier work, we introduced a materialized view based approach for efficiently processing PQs, where the focus was on selecting promising views for materialization. The problem of how to efficiently find usable views from the materialized set in order to answer the SQs for a PQ remains open. In this paper, we present a new index technique, called the Dynamic Materialized View Index (DMVI), to rapidly discover usable views for answering a given SQ. The structure of the proposed index is a special ordered tree where the SQ domain tables are used as search keys and some bitmaps are kept at the leaf nodes for refined filtering. A two-level priority rule is adopted to order domain tables in the tree, which facilitates the efficient maintenance of the tree by taking into account the dynamic characteristics of various types of materialized views for PQs. The bitmap encoding methods and the strategies/algorithms to construct, search, and maintain the DMVI are suggested. The extensive experimental results demonstrate that our index technique is quite promising in improving the performance of the materialized view based query processing approach for PQs

Photocatalytic oxidative desulfurization of dibenzothiophene catalyzed by amorphous TiO2 in ionic liquid

Wenshuai Zhu,Huaming Li,Yehai Xu,Bilian Dai,Hui Xu,Chao Wang,Yanhong Chao,Hui Liu 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.2

Three types of TiO2 were synthesized by a hydrolysis and calcination method. The catalysts were characterizedby X-ray powder diffraction (XRD), diffuse reflectance spectrum (DRS), Raman spectra, and X-ray photoelectronspectroscopy (XPS). The XRD and Raman spectra indicated that amorphous TiO2 was successfully obtained at100 oC. The results indicated that amorphous TiO2 achieved the highest efficiency of desulfurization. The photocatalyticoxidation of dibenzothiophene (DBT), benzothiophene (BT), 4,6-dimethyldibenzothiophene (4,6-DMDBT) anddodecanethiol (RSH) in model oil was studied at room temperature (30 oC) with three catalysts. The system containedamorphous TiO2, H2O2, and [Bmim]BF4 ionic liquid, ultraviolet (UV), which played vitally important roles in the photocatalyticoxidative desulfurization. Especially, the molar ratio of H2O2 and sulfur (O/S) was only 2 : 1, which correspondedto the stoichiometric reaction. The sulfur removal of DBT-containing model oil with amorphous TiO2 couldreach 96.6%, which was apparently superior to a system with anatase TiO2 (23.6%) or with anatase - rutile TiO2 (18.2%). The system could be recycled seven times without a signicant decrease in photocatalytic activity.

Serum Protein and Genetic Tumor Markers of Gastric Carcinoma

He, Chao-Zhu,Zhang, Kun-He Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.6

The high incidence of gastric cancer and consequent mortality pose severe threats to human health. Early screening, diagnosis and treatment are the key to improve the prognosis of the patients with gastric cancer. Gastroscopy with biopsy is an efficient method for the diagnosis of early gastric cancer, but the associated discomfort and high cost make it difficult to be a routine method for screening gastric cancer. Serum tumor marker assay is a simple and practical method for detection of gastric cancer, but it is limited by poor sensitivity and specificity. Therefore, people have been looking for novel serum markers of gastric cancer in recent years. Here we review the novel serum tumor markers of gastric cancer and their diagnostic significance, focusing on the discoveries from serum proteomics analyses and epigenetics researches.

Negative sequence control for DC voltage balancing in three‑phase cascaded H‑bridge rectifiers considering DC‑port failures

Xinyu Zhu,Xiao Liang,Kaiyue Gong,Xu Peng,Jun Cai,Xiaohan Liu,Chao Zhou,Siqi An,Chao Wu,Pengcheng Han 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.12

As a vital component of power electronic transformers (PET), the reliability of a cascaded H-bridge rectifier (CHBR) is essential. Therefore, in this paper, a DC-port voltage balance strategy considering DC-port failure is researched to ensure the stable operation of a CHBR. However, if the DC-port voltage balance strategy is adopted to realize the single-phase balance of a CHBR, the three-phase currents become unbalanced. This paper uses a negative sequence control (NSC) strategy that is conducive to balancing DC-port voltage to achieve three-phase current balance. For the DC-port voltage balance, the matrix generation modulation (MGM) algorithm is proposed. In addition, the DC-port voltage balance boundary is analyzed to determine the range of the DC-port voltage balance in the CHBR. A 3-module cascading topology is adopted to demonstrate the MGM algorithm and the NSC strategy. Through experiments, results show the correctness and feasibility of the proposed strategy.

Influences of flapping modes and wing kinematics on aerodynamic performance of insect hovering flight

Chao Wang,Chaoying Zhou,Xiaorui Zhu 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.4

A numerical investigation into the effects of flapping modes on the aerodynamic performance of insect hovering flight is carried out through the solution of the two-dimensional unsteady Navier-Stokes equations. Four types of idealized flapping modes with the identical quasi-steady lift force are compared, and the influences of the Reynolds number (Re), the translational duration and the rotational duration on the aerodynamic characteristics of the hovering are systematically analyzed flight. It is found that the instantaneous aerodynamic forces of the wing differ significantly in each flapping mode. The mode with harmonic translation and harmonic rotation leading the highest lifting efficiency is suitable for long-time flight while the mode with harmonic translation and trapezoid rotation giving the largest instantaneous forces is suitable for maneuvering flight. When Re increases from 100 to 1000, the lift force and lifting efficiency of the wing are increased significantly with the increasing Re first, and then slow down with the further increase in Re. In addition, the fast-translational mode with short translational duration will reduce the time-averaged lift force and the efficiency, whereas the fastrotational mode with short rotational duration can enhance the time-averaged lift force with the sustained efficiency.

Settlement analysis of viscoelastic foundation under vertical line load using a fractional Kelvin-Voigt model

Zhu, Hong-Hu,Liu, Lin-Chao,Pei, Hua-Fu,Shi, Bin Techno-Press 2012 Geomechanics & engineering Vol.4 No.1

Soil foundations exhibit significant creeping deformation, which may result in excessive settlement and failure of superstructures. Based on the theory of viscoelasticity and fractional calculus, a fractional Kelvin-Voigt model is proposed to account for the time-dependent behavior of soil foundation under vertical line load. Analytical solution of settlements in the foundation was derived using Laplace transforms. The influence of the model parameters on the time-dependent settlement is studied through a parametric study. Results indicate that the settlement-time relationship can be accurately captured by varying values of the fractional order of differential operator and the coefficient of viscosity. In comparison with the classical Kelvin-Voigt model, the fractional model can provide a more accurate prediction of long-term settlements of soil foundation. The determination of influential distance also affects the calculation of settlements.