Compression-bending Performance of L-shaped Column Composed of Concrete Filled Square Steel Tubes under Eccentric Compression

Ruoyu Zhang,Changxi Feng,Ruoyu Zhang,Guangchao You,Rui Liu 한국강구조학회 2017 International Journal of Steel Structures Vol.17 No.1

In order to investigate mechanical properties of L-shaped column composed of concrete-filled square steel tubes (LCFT column) under eccentric compression, LCFT columns were designed and tested. Through two eccentric compression experiments, the failure mode, the curves of loading-displacement for the whole member and the curves of deflection for mono column (single limb of LCFT column) were obtained. Nonlinear finite element analysis was also employed in this investigation, in which thickness of tube flange, connecting plate thickness and diameter of the hole on connecting plate were discussed. According to results of eccentric compression test and finite element analysis, analytical method of bearing capacity of LCFT columns is proposed based on the yielding criterion of the cross-sectional edge stresses. Results of analytical method, finite element analysis and eccentric compression experiment are resistant with each other, and the accuracy of the analytical method in this paper is verified.

Flexural bearing capacity of diaphragm-through joints of concrete-filled square steel tubular columns

Ruoyu Zhang,Bin Rong,Rui Liu,Zhi-Hua Chen,Fafitis Apostolos 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.20 No.3

In order to investigate the flexural bearing capacity of panel zone of diaphragm-through joint between concrete filled square steel tubular column and steel beam, four specimens were tested under static tension loads to study the mechanical properties and bearing capacity of diaphragm-through joints with a failure mode of panel zone. Finite element models of these specimens were developed to simulate the test and compare the predicted failure modes, load-displacement curves and bearing capacities with the experimentally observed. It was found that the tensile load from the steel beam flange is mainly shared by the square steel tube and the diaphragm. The diaphragm plastic zone appears along the cross-section lines enclosed by the square steel tube and the influence of steel beam web on the plastic zone of the steel tube is significant and cannot be neglected. Computational models of yield lines on square steel tube and diaphragm are established based on the distribution pattern of the plastic zone, and an analytical method for the evaluation of the bearing capacity of the joint is proposed. The theoretical results and the experimental data are compared and found in good agreement.

Studies on T-Shaped composite columns consist of multi separate concrete-filled square tubular steel sections under eccentric axial load

Ruoyu Zhang,Bin Rong,Guangchao You,Changxi Feng,Rui Liu 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.22 No.2

In order to investigate mechanical properties and load-bearing capacity of T-shaped Concrete-Filled Square Steel Tubular (TCFST) composite columns under eccentric axial load, three T-shaped composite columns were tested under eccentric compression. Experimental results show that failure mode of the columns under eccentric compression was bending buckling of the whole specimen, and mono column performs flexural buckling. Specimens behaved good ductility and load-bearing capacity. Nonlinear finite element analysis was also employed in this investigation. The failure mode, the load-displacement curve and the ultimate bearing capacity of the finite element analysis are in good agreement with the experimental ones. Based on eccentric compression test and parametric finite element analysis, the calculation formula for the equivalent slenderness ratio was proposed and the bearing capacity of TCFST composite columns under eccentric compression was calculated. Results of theoretical calculation, parametric finite element analysis and eccentric compression experiment accord well with each other, which indicates that the theoretical calculation method of the bearing capacity is advisable.

Classifying imbalanced Internet traffic based PCDD

Ruoyu Wang,Ling Zhang,Zhen Liu 한국산학기술학회 2013 SmartCR Vol.3 No.2

Internet traffic classification is important for network traffic engineering and management. Previous studies have shown that machine learning-based traffic classification methods can obtain high classification accuracy in a static classification context. On the other hand, Internet traffic flows are dynamic, and the classification model needs to be updated at certain intervals. This study first examined the concept drift situation in multi class Internet traffic classification. The classifier obtains high classification accuracy for the majority class over a long period, but looses the classification accuracy for the minority class within a short time. This suggests that concept drift occurs easily in the minority class. To adapt the dynamic classification context, this paper proposes a classification framework based on the concept drift detection method. The experiment results on real traffic datasets showed that the proposed approach can promptly detect concept drift for each class and improve the recall of the minority class while maintaining high overall accuracy.

Rapid Detection of Lily mottle virus and Arabis mosaic virus Infecting Lily (Lilium spp.) Using Reverse Transcription Loop-Mediated Isothermal Amplification

Yubao Zhang,Yajun Wang,Zhongkui Xie,Ruoyu Wang,Zhihong Guo,Yuhui He 한국식물병리학회 2020 Plant Pathology Journal Vol.36 No.2

The Lily mottle virus (LMoV) impedes the growth and quality of lily crops in Lanzhou, China. Recently Arabis mosaic virus (ArMV) has been detected in LMoV- infected plants in this region, causing plant stunting as well as severe foliar symptoms, and likely posing a threat to lily production. Consequently, there is a need to develop simple, sensitive, and reliable detection methods for these two viruses to prevent them from spreading. Reverse transcription (RT) loop-mediated isothermal amplification (LAMP) assays have been de- veloped to detect LMoV and ArMV using two primer pairs that match six conserved sequences of LMoV and ArMV coat proteins, respectively. RT-LAMP assay results were visually assessed in reaction tubes using green fluorescence and gel electrophoresis. Our assays successfully detected both LMoV and ArMV in lily plants without the occurrence of viral cross-reactivity from other lily viruses. Optimal conditions for LAMP reactions were 65°C and 60°C for 60 min for LMoV and ArMV, respectively. Detection sensitivity for both RT-LAMP assays was a hundredfold greater than that of our comparative RT-polymerase chain reaction as- says. We have also found this relatively rapid, target specific and sensitive method can also be used for samples collected in the field and may be especially useful in regions with limited or no laboratory facilities.

Rapid and Sensitive Detection of Lettuce Necrotic Yellows Virus and Cucumber Mosaic Virus Infecting Lettuce (Lactuca sativa L.) by Reverse Transcription Loop-Mediated Isothermal Amplification

Yubao Zhang,Zhongkui Xie,John D Fletcher,Yajun Wang,Ruoyu Wang,Zhihong Guo,Yuhui He 한국식물병리학회 2020 Plant Pathology Journal Vol.36 No.1

Cucumber mosaic virus (CMV) is damaging to the growth and quality of lettuce crops in Lanzhou, China. Recently, however, for the first time an isolate of lettuce necrotic yellows virus (LNYV) has been detected in lettuce crops in China, and there is concern that this virus may also pose a threat to lettuce production in China. Consequently, there is a need to develop a rapid and efficient detection method to accurately identify LNYV and CMV infections and help limit their spread. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) assays were developed to detect the nucleoprotein (N) and coat protein (CP) genes of LNYV and CMV, respectively. RT-LAMP amplification products were visually assessed in reaction tubes separately using green fluorescence and gel electrophoresis. The assays successfully detected both viruses in infected plants without cross reactivity recorded from either CMV or LNYV or four other related plant viruses. Optimum LAMP reactions were conducted in betaine-free media with 6 mM Mg2+ at 65°C for LNYV and 60°C for 60 min for CMV, respectively. The detection limit was 3.5 pg/ml and 20 fg/ml using RT-LAMP for LNYV and CMV plasmids, respectively. Detection sensitivity for both RT-LAMP assays was greater by a factor of 100 compared to the conventional reverse transcription polymerase chain reaction assays. This rapid, specific, and sensitive technique should be more widely applied due to its low cost and minimal equipment requirements.

Synonymy of soil-feeding termites Pseudocapritermes sowerbyi and Pseudocapritermes largus, with evidence from morphology and genetics

Xuan Ruoyue,Dai Qingfeng,He Can,Zhang Dayu,Pan Chengyuan 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.1

Pseudocapritermes Kemner is a termite group that constructs subterranean gallery systems in topsoil. This genus is distributed in the Oriental region and contains 18 species. Dependence on the morphological measurements of soldiers makes the taxonomy of Pseudocapritermes difficult. In this study, we compared morphological characters of soldiers and adults of P. largus and P. sowerbyi. In addition, three fulllength mitochondrial genes (COI, COII, and 16S rRNA) were sequenced from a total of eight P. largus and P. sowerbyi colonies. Morphological comparison of soldiers showed that P. largus is larger than P. sowerbyi, but there was overlap in some measurements. In adults, the morphological characters of P. largus were congruent with those of P. sowerbyi. Sequence alignments of COI, COII, and 16S rRNA revealed a high pairwise genetic identity (ranging from 99.64 to 100%) between the two species, which suggested that P. largus and P. sowerbyi are the same species. Molecular phylogenetic analysis based on COII revealed that Pseudocapritermes belongs to the Termes group having soldiers with asymmetrical snapping mandibles and is more closely related to Sinocapritermes than to other Termes group genera distributed in China. Morphological similarity and genetic identity indicate that P. largus is a junior synonym of P. sowerbyi.

Intensity noise suppression in mode-locked fiber lasers by double optical bandpass filtering

Kim, Dohyun,Zhang, Shuangyou,Kwon, Dohyeon,Liao, Ruoyu,Cui, Yifan,Zhang, Zhigang,Song, Youjian,Kim, Jungwon OPTICAL SOCIETY OF AMERICA 2017 Optics letters Vol.42 No.20

Long-Term Outcomes of Stenting on Non-Acute Phase Extracranial Supra-Aortic Dissections

Jiang, Yeqing,Di, Ruoyu,Lu, Gang,Huang, Lei,Wan, Hailin,Ge, Liang,Zhang, Xiaolong The Korean Neurosurgical Society 2022 Journal of Korean neurosurgical society Vol.65 No.3

Objective : Extracranial supra-aortic dissections (ESADs) with severe stenosis, occlusion and/or pseudoaneurysm presents potential risk of stroke. Endovascular stenting to reconstruct non acute phase ESADs (NAP-ESADs) is an alternative to anticoagulant or antiplatelet therapy. However, its feasibility, safety and efficacy of stenting in NAP-ESADs is unclear. This study aims to investigate the long-term outcomes of the feasibility, safety and efficacy of stenting in NAP-ESADs. Methods : Seventy-four patients with 91 NAP-ESAD vessels with severe stenosis, occlusion and/or pseudoaneurysm presents potential risk of stroke who underwent stent remodeling were enrolled into this respective study from December 2008 to March 2020. Technical success rate, complications, clinical and angiographic results were harvested and analyzed. Results : Success rate of stent deployment was 99% (90/91) with no procedural mortality or morbidity. Transient ischemic attack occurred in three patients during operation (4.1%, 3/74). Asymptomatic embolisms of distal intracranial vessels were found in two patients (2.7%, 2/74). One hundred and forty-two stents deployed at 85 carotid (135 stents) and six vertebral (seven stents) vessels. Six stent types (Wingspan, 28/135, 20.7%; Solitaire, 10/135, 7.4%; Neuroform, 8/135, 5.9%; LVIS, 2/135, 1.5%; Precise, 75/135, 55.6%; Acculink, 12/135, 8.9%) were deployed at carotid arterial dissection while two types (Wingspan, 5/7, 71.4%; Solitaire 2/7, 28.6%) at vertebral arterial dissection. Digital subtracted angiography (56%, 51/91), computational tomography angiography (41.8%, 38/91) and high resolution magnetic resonance imaging (2.2%, 2/91) were adopted for follow up, with a mean time of 17.2±15.4 months (5-77). All patient modified Rankin Scale scores showed no increase at discharge or follow-up. Angiographically, dissections in 86 vessels in 69 patients (94.5%, 86/91) were completely reconstructed with only minor remnant dissections in four vessels in four patients (4.4%, 4/91). Severe re-stenosis in the stented segment required re-stenting in one patient (1.1%, 1/91). Conclusion : Stent remodeling technique provides feasible, safe and efficacious treatment of ESADs patients with severe stenosis, occlusion and/or pseudoaneurysm.

Experimental and theoretical studies on SHS column connection with external stiffening ring under static tension load

Bin Rong,Guangchao You,Ruoyu Zhang,Xu Ma,Xinxin Quan 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.28 No.2

In order to investigate mechanical properties in the core area of Square Hollow Section(SHS) column connection with external stiffening ring, four specimens were tested under the static tension load. The failure modes, load-displacement curves and strain distribution were analyzed to study the mechanical properties and the load transfer mechanism of the core area of connections. The connections behave good ductility and load-bearing capacity under the static tension load. Parametric analysis was also conducted, in which the thickness of steel tube, extended width and thickness of the stiffening ring were considered as the parameters to investigate the effects on mechanical properties of the connections. Based on the experimental results, an analytical method for the bearing capacity of connection with external stiffening ring under the static tension load was proposed. The theoretical results and the experimental results are in good agreement, which indicates that the theoretical calculation method of the bearing capacity is advisable.