Research of Acoustic Emission Testing Method with Application to Monitored for Wind Turbines

Qin Hongwu,Zhang Chao,Zhang Xian,Fan Qinyin 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.1

Acoustic Emission method of nondestructive check is based on exertion wave radiation and their registration during fast local material structure reorganization. It is used as a means of analysis of materials, constructions, productions control and diagnosis during operating time. In the article, it is applied to structural health monitoring of Wind Turbines. Acoustic emission testing is based condition monitoring system uses data already collected at the wind turbine controller. It is an effective way to monitor wind turbines for early warning of failures and performance issues. We used a number of measurements to develop anomaly detection algorithms and investigated classification techniques using clustering algorithms and principal components analysis for capturing fault signatures. When registering signal amplitude it is required to consider its frequency distribution connecting each amplitude rate with the corresponding vibration rate. The correlation and signal to noise ratio were evaluated by the algorithm based on frequency spectrum. Classical method of frequency distortion influence exclusion consists of FRF calculation with subsequent adjustment of received signals spectral characteristics.

Determination of flutter derivatives by stochastic subspace identification technique

Qin, Xian-Rong,Gu, Ming Techno-Press 2004 Wind and Structures, An International Journal (WAS Vol.7 No.3

Flutter derivatives provide the basis of predicting the critical wind speed in flutter and buffeting analysis of long-span cable-supported bridges. In this paper, one popular stochastic system identification technique, covariance-driven Stochastic Subspace Identification(SSI in short), is firstly presented for estimation of the flutter derivatives of bridge decks from their random responses in turbulent flow. Secondly, wind tunnel tests of a streamlined thin plate model and a ${\Pi}$ type blunt bridge section model are conducted in turbulent flow and the flutter derivatives are determined by SSI. The flutter derivatives of the thin plate model identified by SSI are very comparable to those identified by the unifying least-square method and Theodorson's theoretical values. As to the ${\Pi}$ type section model, the effect of turbulence on aerodynamic damping seems to be somewhat notable, therefore perhaps the wind tunnel tests for flutter derivative estimation of those models with similar blunt sections should be conducted in turbulent flow.

Determination of flutter derivatives by stochastic subspace identification technique

Xian-rong Qin,Ming Gu 한국풍공학회 2004 Wind and Structures, An International Journal (WAS Vol.7 No.3

Sub-micro Particles Prepared by Reaction-precipitation Crystallization

Wang Xian-Qin,Jun-LI Tang 한국분말야금학회 2006 한국분말야금학회 학술대회논문집 Vol.2006 No.1

Tumor Markers for Diagnosis, Monitoring of Recurrence and Prognosis in Patients with Upper Gastrointestinal Tract Cancer

Jing, Jie-Xian,Wang, Yan,Xu, Xiao-Qin,Sun, Ting,Tian, Bao-Guo,Du, Li-Li,Zhao, Xian-Wen,Han, Cun-Zhi Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

To evaluate the value of combined detection of serum CEA, CA19-9, CA24-2, AFP, CA72-4, SCC, TPA and TPS for the clinical diagnosis of upper gastrointestinal tract (GIT) cancer and to analyze the efficacy of these tumor markers (TMs) in evaluating curative effects and prognosis. A total of 573 patients with upper GIT cancer between January 2004 and December 2007 were enrolled in this study. Serum levels of CEA, CA19-9, CA24-2, AFP, CA72-4, SCC, TPA and TPS were examined preoperatively and every 3 months postoperatively by ELISA. The sensitivity of CEA, CA19-9, CA24-2, AFP, CA72-4, SCC, TPA and TPS were 26.8%, 36.2%, 42.9%, 2.84%, 25.4%, 34.6%, 34.2% and 30.9%, respectively. The combined detection of CEA+CA199+CA242+CA724 had higher sensitivity and specificity in gastric cancer (GC) and cardiac cancer, while CEA+CA199+CA242+SCC was the best combination of diagnosis for esophageal cancer (EC). Elevation of preoperative CEA, CA19-9 and CA24-2, SCC and CA72-4 was significantly associated with pathological types (p<0.05) and TNM staging (p<0.05). Correlation analysis showed that CA24-2 was significantly correlated with CA19-9 (r=0.810, p<0.001). The levels of CEA, CA19-9, CA24-2, CA72-4 and SCC decreased obviously 3 months after operations. When metastasis and recurrence occurred, the levels of TMs significantly increased. On multivariate analysis, high preoperative CA72-4, CA24-2 and SCC served as prognostic factors for cardiac carcinoma, GC and EC, respectively. combined detection of CEA+CA199+CA242+SCC proved to be the most economic and practical strategy in diagnosis of EC; CEA+CA199+CA242+CA724 proved to be a better evaluation indicator for cardiac cancer and GC. CEA and CA19-9, CA24-2, CA72-4 and SCC, examined postoperatively during follow-up, were useful to find early tumor recurrence and metastasis, and evaluate prognosis. AFP, TPA and TPS have no significant value in diagnosis of patients with upper GIT cancer.

Synthesis and Optical Characteristics of PAM/HgS Nanocomposites

Qin, Dezhi,Yang, Guangrui,Zhang, Li,Du, Xian,Wang, Yabo Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.4

Polyacrylamide (PAM) -HgS nanocomposites were successfully prepared in polyacrylamide (PAM) matrix. From TEM and XRD characterizations, the synthesized HgS nanocrystals were chain-like spherical in shape with a diameter of about 40-60 nm and high crystalline quality. The quantum-confined effect of HgS nanocrystals was confirmed by UV-vis diffuse reflection spectra. The optical properties of products were investigated by using photoluminescence (PL) spectra, which showed that HgS nanocrystals exhibited good optical properties with maximum emission peak at about 640 and 650 nm at different reaction temperatures. The interaction of HgS nanocrystals with PAM was studied through FT-IR spectroscopy and TG analysis, which suggested that $Hg^{2+}$ could interact with functional groups of PAM. The experimental results indicated that PAM not only induced nucleation, but also inhibited further growth of HgS crystals and play an important role in the formation of PAM/HgS nanocomposites. In addition, the possible mechanism of HgS nanoparticles growth in PAM solution was also discussed.

Significant Efficacy of Additional Concurrent Chemotherapy with Radiotherapy for Postoperative Cervical Cancer with Risk Factors: a Systematic Review and Meta-analysis

Qin, Ai-Qiu,Liang, Zhong-Guo,Ye, Jia-Xiang,Li, Jing,Wang, Jian-Li,Chen, Chang-Xian,Song, Hong-Lin Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.8

Background: Whether concurrent chemotherapy treatment is superior to radiotherapy alone as an adjuvant regimen for postoperative cervical carcinoma with risk factors remains controversial. Materials and Methods: A literature search strategy examined Pubmed, Embase, the Cochrane Library, the China National Knowledge Internet Web, the Chinese Biomedical Database and the Wanfang Database. Article reference lists and scientific meeting abstracts were also screened. Controlled trials comparing concurrent chemoradiotherapy versus radiotherapy alone in postoperative cervical cancer were included. The methodological quality of non-randomized controlled trials was evaluated using the Newcastle-Ottawa Scale. Randomized controlled studies were evaluated with the Cochrane handbook. A meta-analysis was performed with RevMan 5.3. Results: A total of 1,073 patients from 11 clinical trials were analysed, with 582 patients in the concurrent chemoradiotherapy group and 491 patients in the radiotherapy group. Hazard ratios (HR) of 0.47 (95% CI 0.31-0.72) and 0.50 (95% CI 0.35-0.72) were observed for overall survival and progression-free survival, indicating a benefit from the additional use of concurrent chemotherapy. Subgroup analyses demonstrated that cervical cancer with high risk factors significantly benefitted from concurrent chemotherapy when examining overall survival (HR 0.44, 95% CI 0.28-0.67) and progression-free survival (HR 0.48, 95% CI 0.33-0.70), but patients with intermediate risk factors showed no benefit from concurrent chemotherapy in overall survival (HR 1.72, 95% CI 0.28-10.41) and progression-free survival (HR 1.09, 95% CI 0.19-6.14). No significant differences were observed for grade 3-4 anaemia (risk ratio (RR) 3.87, 95% CI 0.69-21.84), grade 3-4 thrombocytopenia (RR 3.04, 95% CI 0.88-10.58), grade 3-4 vomiting or nausea (RR 1.71, 95% CI 0.27-10.96), or grade 3-4 diarrhoea (RR 1.40, 95% CI 0.69-2.83). Significant differences were observed for grade 3-4 neutropenia in favour of the radiotherapy group (RR 7.23, 95% CI 3.94-13.26). Conclusions: In conclusion, concurrent chemoradiotherapy improves survival in postoperative cervical cancer with high risk factors but not in those with intermediate risk factors.

Disruption of the Myostatin Gene in Porcine Primary Fibroblasts and Embryos Using Zinc-Finger Nucleases

Xian-Ju Huang,Hong-Xiao Zhang,Huili Wang,Kai Xiong,Ling Qin,Honglin Liu 한국분자세포생물학회 2014 Molecules and cells Vol.37 No.4

Myostatin represses muscle growth by negatively regulating the number and size of muscle fibers. Myostatin loss-of-function can result in the double-muscling phenotype and increased muscle mass. Thus, knockout of myostatin gene could improve the quality of meat from mammals. In the present study, zinc finger nucleases, a useful tool for generating gene knockout animals, were designed to target exon 1 of the myostatin gene. The designed ZFNs were introduced into porcine primary fibroblasts and early implantation embryos via electroporation and microinjection, respectively. Mutations around the ZFNs target site were detected in both primary fibroblasts and blastocysts. The proportion of mutant fibroblast cells and blastocyst was 4.81% and 5.31%, respectively. Thus, ZFNs can be used to knockout myostatin in porcine primary fibroblasts and early implantation embryos.

Analysis Technique of Spectral Characteristics AE Signals with Application to Monitored for WT

Qin Hongwu,Zhang Xian,Chu Wei,Fan Qinyin,Peng Jincheng,Jia Tongli 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.1

The paper presents the results of an assessment with a range as real AE signals are received at destruction of spot welding, and imitated by means of a AE transducer are given in work, efficiency use of high-frequency area for recognition of AE signals against hindrances is shown. The actuator is excited by an impulse signal instead of a sinewave, and the responses are measured with the PE sensors. The spectral characteristics of AE signals should use broadband transducers with the rise in the PE side of the treble to compensate for PE of the sample, and partly of the signal spectrum, which is reduced the measurement error of the absolute values. The damage could be indicated in an experiment, but it turned out that the sensitivity is low if the damage is not in the path between actuator and sensor. When a machine has a mistake, it leads to energy loss and results in the transformation of sound, heat and the whole performance. The basis of most condition monitoring techniques WT has been constructed by the various features.

Studies on meat color, myoglobin content, enzyme activities, and genes associated with oxidative potential of pigs slaughtered at different growth stages

Qin Ping Yu,Ding Yuan Feng,Juan Xiao,Fan Wu,Xiao Jun He,Min Hao Xia,Tao Dong,Yi Hua Liu,Hui Ze Tan,Shi Geng Zou,Tao Zheng,Xian Hua Ou,Jian Jun Zuo 아세아·태평양축산학회 2017 Animal Bioscience Vol.30 No.12

Objective: This experiment investigated meat color, myoglobin content, enzyme activities, and expression of genes associated with oxidative potential of pigs slaughtered at different growth stages. Methods: Sixty 4-week-old Duroc×Landrace×Yorkshire pigs were assigned to 6 replicate groups, each containing 10 pigs. One pig from each group was sacrificed at day 35, 63, 98, and 161 to isolate longissimus dorsi and triceps muscles. Results: Meat color scores were higher in pigs at 35 d than those at 63 d and 98 d (p<0.05), and those at 98 d were lower than those at 161 d (p<0.05). The total myoglobin was higher on 161 d compared with those at 63 d and 98 d (p<0.05). Increase in the proportions of metmyoglobin and deoxymyoglobin and a decrease in oxymyoglobin were observed between days 35 and 161 (p<0.05). Meat color scores were correlated to the proportion of oxymyoglobin (r = 0.59, p<0.01), and negatively correlated with deoxymyoglobin and metmyoglobin content (r = –0.48 and –0.62, p<0.05). Malate dehydrogenase (MDH) activity at 35 d and 98 d was higher than that at 161 d (p<0.05). The highest lactate dehydrogenase/MDH ratio was achieved at 161 d (p<0.05). Calcineurin mRNA expression decreased at 35 d compared to that at 63 d and 98 d (p<0.05). Myocyte enhancer factor 2 mRNA results indicated a higher expression at 161 d than that at 63 d and 98 d (p<0.05). Conclusion: Porcine meat color, myoglobin content, enzyme activities, and genes associated with oxidative potential varied at different stages.