Effect of Global Warming on Chloride Ion Erosion Risks for Offshore RC Bridges in China

Hui-bing Xie,Yuan-Feng Wang,Jian Gong,Ming-hui Liu,Xiao-Yuan Yang 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.9

Chloride ion penetration, which leads to corrosion of steel reinforcement, is the leading cause of offshore reinforced concrete bridge deterioration. Global warming would accelerate the process of chloride ion penetration and then structural degradation. In China, durability design code for concrete structures has been issued in 2008, and some thresholds of design parameters have been specified to mitigate corrosion in concrete bridge. However, influence of global warming on structure durability was not considered in the issued code. This would overestimate the durability of concrete structures. In this paper, a reliability based method was adopted to evaluate the influence of climate change on the durability of offshore RC bridges considering the acceleration of chloride ion penetration caused by temperature rise. Two climate change scenarios according to IPCC report were considered to define the global warming. A baseline scenario, in which the mean average temperature equals to that of the year 2000, were defined. It is found that the amount of chloride ion on the surface of reinforcing steel bar in the global warming scenarios are 6%-15% higher than that of structure in the baseline scenario. Meanwhile, the probability of corrosion initiation and corrosion damage increased also. In 2100, structures in environmental categories III-C and III-F, designed according to Chinese codes, can no longer adapt the impact of climate change on structure. Comparison of reliability of improved and pre-improved structure was conducted to verify the effectiveness of the proposed improvement measures.

Friction and Wear Characteristics of 20Cr Steel Substrate and TiAlN Coating under Different Lubrication Conditions

Yuan-ming Li,Qi-Bin Yue,Hua-Ying Li,Hui-Bo He 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.10

TiAlN coating was deposited on the surface of 20Cr steel samples by physical vapor deposition. TiAlN coated samples and 20Cr steel matrix samples were in three conditions of friction to do reciprocating friction and wear tests with a Si3N4 ceramic ball friction pair which was loaded 2, 5 and 8 N. The wear images and the distribution of elements were obtained by the scanning electron microscope and the energy spectrometer respectively. Then the three-dimensional profile meter was used to get the profile of the grinding marks and the step meter gained two-dimensional contour curve. Results of investigation showed that the friction coefficient of TiAlN waterbased lubrication friction increased with the increase of the load, and TiAlN oil-based lubrication friction had the same rule. Under 5 and 8 N loads, the friction coefficients were higher than both of TiAlN and 20Cr steel matrix dry friction in the middle friction stage. As concluded through the experimental analysis, abrasive wear was the main wear mechanism of dry friction; the fatigue wear and oxidation wear were accompanied in some conditions. Water had a great influence on the micro morphology of the grinding mark. The wear of 20Cr steel matrix is the most serious.

Port-Site Metastases and Chimney Effect of B-Ultrasound-Guided and Laparoscopically-Assisted Hyperthermic Intraperitoneal Perfusion Chemotherapy

Ming-Chen Ba,Hui Long,Xiang-Liang Zhang,Yuan-Feng Gong,Zhao-Fei Yan,Shuai Wang,Yun-Qiang Tang,Shu-Zhong Cui 연세대학교의과대학 2017 Yonsei medical journal Vol.58 No.3

Purpose: CO2 leakage along the trocar (chimney effect) has been proposed to be an important factor underlying port-site metastasisafter laparoscopic surgery. This study aimed to test this hypothesis by comparing the incidence of port-site metastasis betweenB-ultrasound-guided and laparoscopically-assisted hyperthermic intraperitoneal perfusion chemotherapy (HIPPC). Materials and Methods: Sixty-two patients with malignant ascites induced by gastrointestinal or ovarian cancer were divided into two groups to receive either B-ultrasound-guided or laparoscopically-assisted HIPPC. Clinical efficacy was assessed from the objective remission rate (ORR), the Karnofsky Performance Status (KPS) score, and overall survival. The incidence of port-site metastasis was compared between the two groups. Results: Patients in the B-ultrasound (n=32) and laparoscopy (n=30) groups were comparable in terms of age, sex, primary diseasetype, volume of ascites, and free cancer cell (FCC)-positive ascites. After HIPPC, there were no significant differences between the B-ultrasound and laparoscopy groups in the KPS score change, ORR, and median survival time. The incidence of port-site metastasis after HIPPC was not significantly different between the B-ultrasound (3 of 32, 9.36%) and laparoscopy (3 of 30, 10%) groups, but significantly different among pancreatic, gastric, ovarian, and colorectal cancer (33.33, 15.79, 10.00, and 0.00%, p<0.001). Conclusion: The chimney effect may not be the key reason for port-site metastasis after laparoscopy. Other factors may play a role, including the local microenvironment at the trocar site and the delivery of viable FCCs (from the tumor or malignant ascites) to the trauma site during laparoscopic surgery.

Efficient slope reliability analysis using a surrogate-assisted normal search particle swarm optimization algorithm

Yuan Yi-li,Hu Chang-ming,LI LIANG,Hou Xu-hui 한국CDE학회 2024 Journal of computational design and engineering Vol.11 No.1

Sampling of training data is the most important step in active learning slope reliability analysis, which controls the analysis accuracy. In this study, a novel surrogate-assisted normal search particle swarm optimization (SANSPSO) was proposed to enhance the accuracy and robustness of existing methodologies. In SANSPSO, the sampling process was considered a minimum problem with an objective function defined as the absolute value of the performance function. Initiated with a normal search paradigm and supplemented by three algorithm strategies, this approach seeks to preserve the continuity of the solution while refining the algorithm’s efficacy and efficiency. To reduce computation cost, surrogate-assistance was used, in which a surrogate model substitutes the objective function in most iterations. This surrogate model evolves during the iteration process and ultimately replaces the actual performance function within Monte Carlo simulation. Finally, this study presents a comparative study with five state-of-the-art methods across four explicit problems and three engineering cases, where test data suggest that the SANSPSO methodology yields a 20% improvement in accuracy and a 30% rise in stability under different dimensional problems relative to the most efficacious of the alternate methods assessed because of the improved and more consistent prediction of limit state function. These findings substantiate the validity and robustness of the SANSPSO approach.

Research on the Cutting Performances and Wear Mechanisms of TiAlCrN Coated Tools during Dry Turning

Hui-Bo He,Hua-Ying Li,Xian-Ying Zhang,Qi-Bin Yue,Jun Zhang,Lu Ma,Yuan-ming Li 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.2

Physical vapour deposition technique was used to deposit TiAlCrN coatings on the YT15 tungsten carbide inserts. The dry turning tests of 20CrMo steel were carried out to evaluate performances of TiAlCrN coated and uncoated tools on the CA6140A lathe. The effect of the two kinds of tools on cutting forces, cutting temperature, surface roughness and tool wear had been investigated to assess the performance of TiAlCrN coated tools. The results showed that the cutting force and cutting temperature obtained by TiAlCrN coated tools were decreased and the TiACrN coated tools produced a better surface finish in comparison with the uncoated tools. The TiAlCrN coated tools yield working life about 45 min, which was two times of that for uncoated tools. The wear mechanisms of the TiAlCrN coated tools were mainly oxidation and boundary wear, accompanied with diffusion wear.

Study on Breakup of Conical Liquid Sheet under Varying Flow Conditions

( Ming Yue ),( Hang Xu ),( Mao Lin Yang ),( Hui Jin Yuan ),( Sen Zhi Sheng ) 한국액체미립화학회 2001 한국액체미립화학회 학술강연회 논문집 Vol.2001 No.-

Novel and Effective Almagate Enema for Hemorrhagic Chronic Radiation Proctitis and Risk Factors for Fistula Development

Yuan, Zi-Xu,Ma, Teng-Hui,Zhong, Qing-Hua,Wang, Huai-Ming,Yu, Xi-Hu,Qin, Qi-Yuan,Chu, Li-Li,Wang, Lei,Wang, Jian-Ping Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.2

Radiation proctitis is a common complication after radiotherapy for pelvic malignant tumors. This study was conducted to assess the efficacy of novel almagate enemas in hemorrhagic chronic radiation proctitis (CRP) and evaluate risk factors related to rectal deep ulcer or fistula secondary to CRP. All patients underwent a colonoscopy to confirm the diagnosis of CRP and symptoms were graded. Typical endoscopic and pathological images, risk factors, and quality of life were also recorded. A total of 59 patients were enrolled. Gynecological cancers composed 93.1% of the primary malignancies. Complete or obvious reduction of bleeding was observed in 90% (53/59) patients after almagate enema. The mean score of bleeding improved from 2.17 to 0.83 (P<0.001) after the enemas. The mean response time was 12 days. No adverse effects were found. Moreover, long-term successful rate in controlling bleeding was 69% and the quality of life was dramatically improved (P=0.001). The efficacy was equivalent to rectal sucralfate, but the almagate with its antacid properties acted more rapidly than sucralfate. Furthermore, we firstly found that moderate to severe anemia was the risk factor of CRP patients who developed rectal deep ulcer or fistulas (P= 0.015). We also found abnormal hyaline-like thick wall vessels, which revealed endarteritis obliterans and the fibrosis underlying this disease. These findings indicate that almagate enema is a novel effective, rapid and well-tolerated method for hemorrhagic CRP. Moderate to severe anemia is a risk factor for deep ulceration or fistula.

Physical Layer Security in Heterogeneous Cellular Networks

Hui-Ming Wang,Tong-Xing Zheng,Jinhong Yuan,Towsley, Don,Moon Ho Lee IEEE 2016 IEEE TRANSACTIONS ON COMMUNICATIONS Vol.64 No.3

<P>The heterogeneous cellular network (HCN) is a promising approach to the deployment of 5G cellular networks. This paper comprehensively studies physical layer security in a multitier HCN where base stations (BSs), authorized users, and eavesdroppers are all randomly located. We first propose an access threshold-based secrecy mobile association policy that associates each user with the BS providing the maximum truncated average received signal power beyond a threshold. Under the proposed policy, we investigate the connection probability and secrecy probability of a randomly located user and provide tractable expressions for the two metrics. Asymptotic analysis reveals that setting a larger access threshold increases the connection probability while decreases the secrecy probability. We further evaluate the network-wide secrecy throughput and the minimum secrecy throughput per user with both connection and secrecy probability constraints. We show that introducing a properly chosen access threshold significantly enhances the secrecy throughput performance of a HCN.</P>

Hydrogen-water ameliorates radiation-induced gastrointestinal toxicity via MyD88’s effects on the gut microbiota

Hui-wen Xiao,Yuan Li,Dan Luo,Jia-li Dong,Li-xin Zhou,Shu-yi Zhao,Qi-sheng Zheng,Hai-chao Wang,Ming Cui,Sai-jun Fan 생화학분자생물학회 2018 Experimental and molecular medicine Vol.50 No.-

Although radiation therapy is a cornerstone of modern management of malignancies, various side effects are inevitably linked to abdominal and pelvic cancer after radiotherapy. Radiation-mediated gastrointestinal (GI) toxicity impairs the life quality of cancer survivors and even shortens their lifespan. Hydrogen has been shown to protect against tissue injuries caused by oxidative stress and excessive inflammation, but its effect on radiation-induced intestinal injury was previously unknown. In the present study, we found that oral gavage with hydrogen-water increased the survival rate and body weight of mice exposed to total abdominal irradiation (TAI); oral gavage with hydrogen-water was also associated with an improvement in GI tract function and the epithelial integrity of the small intestine. Mechanistically, microarray analysis revealed that hydrogen-water administration upregulated miR-1968-5p levels, thus resulting in parallel downregulation of MyD88 expression in the small intestine after TAI exposure. Additionally, high-throughput sequencing showed that hydrogen-water oral gavage resulted in retention of the TAI-shifted intestinal bacterial composition in mice. Collectively, our findings suggested that hydrogen-water might be used as a potential therapeutic to alleviate intestinal injury induced by radiotherapy for abdominal and pelvic cancer in preclinical settings.

Significantly Enhanced Production of Acarbose in Fed-Batch Fermentation with the Addition of S-Adenosylmethionine

( Li Hui Sun ),( Ming Gang Li ),( Yuan Shan Wang ),( Yu Guo Zheng ) 한국미생물 · 생명공학회 2012 Journal of microbiology and biotechnology Vol.22 No.6

Acarbose, a pseudo-oligosaccharide, is widely used clinically in therapies for non-insulin-dependent diabetes. In the present study, S-adenosylmethionine (SAM) was added to selected media in order to investigate its effect on acarbose fermentation by Actinoplanes utahensis ZJB- 08196. Acarbose titer was seen to increase markedly when concentrations of SAM were added over a period of time. The effects of glucose and maltose on the production of acarbose were investigated in both batch and fed-batch fermentation. Optimal acarbose production was observed at relatively low glucose levels and high maltose levels. Based on these results, a further fed-batch experiment was designed so as to enhance the production of acarbose. Fed-batch fermentation was carried out at an initial glucose level of 10 g/l and an initial maltose level of 60 g/l. Then, 12 h post inoculation, 100 μmol/l SAM was added. In addition, 8 g/l of glucose was added every 24 h, and 20 g/l of maltose was added at 96 h. By way of this novel feeding strategy, the maximum titer of acarbose achieved was 6,113 mg/l at 192 h. To our knowledge, the production level of acarbose achieved in this study is the highest ever reported.