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Interval oscillation criteria for a second order nonlinear differential equation
Cun-Hua Zhang 한국전산응용수학회 2009 Journal of applied mathematics & informatics Vol.27 No.5
This paper is concerned with the interval oscillation of the second order nonlinear ordinary differential equation (r (t) |y' (t)α−1 y'(t)' + p (t) |y' (t)α−1 y'(t)+q (t) f (y (t)) g (y'(t)) = 0. By constructing a generalized Riccati transformation and using the method of averaging techniques, we establish some interval oscillation criteria when f(y) is not differetiable but satisfies the condition<수식> μ0 > 0 for y ≠ 0. This paper is concerned with the interval oscillation of the second order nonlinear ordinary differential equation (r (t) |y' (t)α−1 y'(t)' + p (t) |y' (t)α−1 y'(t)+q (t) f (y (t)) g (y'(t)) = 0. By constructing a generalized Riccati transformation and using the method of averaging techniques, we establish some interval oscillation criteria when f(y) is not differetiable but satisfies the condition<수식> μ0 > 0 for y ≠ 0.
Research on the Compression Behavior of Steel Reinforced Concrete Columns With Built-in Steel Tubes
Cun Hui,Fan Zhang,Zhizeng Zhang,Xiaoli Liu,Ran Hai,John J. Myers 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.4
In order to study the compression behavior of rectangular steel reinforced concrete columns with built-in steel tubes under diff erent eccentric loads, three 1/10 scale specimens were designed and monotonic loading tests were carried out on them. The dimensions, steel bars and steel tube of the three specimens were the same except for the location of the loading point. The eccentricity ratios of the three specimens were 0, 0.25 and 0.5, respectively. The failure modes, load-bearing capacity and displacement characteristics of the test specimens were analyzed. According to the Chinese code, the load-bearing capacity calculation principles and methods of steel reinforced concrete columns with built-in steel tube were investigated for the comparison. The study shows that the peak vertical loads of specimens decrease and the corresponding vertical and horizontal peak displacement increase as the eccentricity increases. The load-bearing capacity calculation results from Chinese code are slightly smaller than the test result because of the unconsidered sleeve eff ect of the internal steel tube. The errors between them are small, and the calculation methods are benefi cial to ensure the structural safety.
WAVEFRONT SOLUTIONS IN THE DIFFUSIVE NICHOLSON'S BLOWFLIES EQUATION WITH NONLOCAL DELAY
Zhang, Cun-Hua The Korean Society for Computational and Applied M 2010 Journal of applied mathematics & informatics Vol.28 No.1
In the present article we consider the diffusive Nicholson's blowflies equation with nonlocal delay incorporated into an integral convolution over all the past time and the whole infinite spatial domain $\mathbb{R}$. When the kernel function takes a special function, we construct a pair of lower and upper solutions of the corresponding travelling wave equation and obtain the existence of travelling fronts according to the existence result of travelling wave front solutions for reaction diffusion systems with nonlocal delays developed by Wang, Li and Ruan (J. Differential Equations, 222(2006), 185-232).
INTERVAL OSCILLATION CRITERIA FOR A SECOND ORDER NONLINEAR DIFFERENTIAL EQUATION
Zhang, Cun-Hua The Korean Society for Computational and Applied M 2009 Journal of applied mathematics & informatics Vol.27 No.5
This paper is concerned with the interval oscillation of the second order nonlinear ordinary differential equation (r(t)|y'(t)|$^{{\alpha}-1}$ y'(t))'+p(t)|y'(t)|$^{{\alpha}-1}$ y'(t)+q(t)f(y(t))g(y'(t))=0. By constructing ageneralized Riccati transformation and using the method of averaging techniques, we establish some interval oscillation criteria when f(y) is not differetiable but satisfies the condition $\frac{f(y)}{|y|^{{\alpha}-1}y}$ ${\geq}{\mu}_0$ > 0 for $y{\neq}0$.
WAVEFRONT SOLUTIONS IN THE DIFFUSIVE NICHOLSON’S BLOWFLIES EQUATION WITH NONLOCAL DELAY
Cun-Hua Zhang 한국전산응용수학회 2010 Journal of applied mathematics & informatics Vol.28 No.1
In the present article we consider the diffusive Nicholson’s blowflies equation with nonlocal delay incorporated into an integral convolution over all the past time and the whole infinite spatial domain R. When the kernel function takes a special function, we construct a pair of lower and upper solutions of the corresponding travelling wave equation and obtain the existence of travelling fronts according to the existence result of travelling wave front solutions for reaction diffusion systems with nonlocal delays developed byWang, Li and Ruan (J. Differential Equations,222(2006), 185-232).
Chong Zhi Zhang,Hai Zhou Sun,Sheng Li Li,Dan Sang,Chun Hua Zhang,Lu Jin,Marco Antonini,Cun Fa Zhao 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.4
Objective: This study investigated the effects of photoperiod on nutrient digestibility, hair follicle (HF) activity and cashmere quality in Inner Mongolia white cashmere goats. Methods: Twenty-four female (non-pregnant) Inner Mongolia white cashmere goats aged 1 to 1.5 years old with similar live weights (mean, 20.36±2.63 kg) were randomly allocated into two groups: a natural daily photoperiod group (NDPP group:10 to 16 h light, n = 12) and a short daily photoperiod group (SDPP group: 7 h light:17 h dark, n = 12). All the goats were housed in individual pens and fed the same diets from May 15 to October 15, 2015. The digestibility of crude protein (CP), dry matter (DM), and neutral detergent fiber (NDF) were measured in different months, along with secondary hair follicle (SHF) activity, concentration of melatonin (MEL), and cashmere quality. Results: Although there was no significant difference in the live weights of goats between the SDPP and NDPP groups (p>0.05), the CP digestibility of goats in the SDPP group was significantly increased compared to the NDPP group in July, September, and October (p<0.05). For the DM and NDF digestibility of goats, a significant increase (p<0.05) was found during in September in the SDPP group. Furthermore, compared to the NDPP group, the SHF activity in July, the MEL concentration in July, and the cashmere fiber length and fiber weight in October were significantly increased in the SDPP group (p<0.05). Conclusion: The cashmere production of Inner Mongolia white cashmere goats was increased without obvious deleterious effects on the cashmere fibers in the SDPP group (metabolizable energy, 8.34 MJ/kg; CP, 11.16%; short daily photoperiod, 7 h light:17 h dark).
Prevalence and Pathogenesis of Barrett's Esophagus in Luoyang, China
Zhang, Ru-Gang,Wang, Chang-Song,Gao, Cun-Fang Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.5
Background: Prevalence of Barrett's esophagus (BE) in Luoyang, China, has not been reported, and its pathogenesis is controversial. The aim of this study was therefore to investigate the prevalence of BE and its underlying factors in the city of Luoyang. Method: This was a prospective study in one center. Many patients were analyzed using endoscopy who showed upper gastrointestinal symptoms between August 2006 and June 2007. In addition, the effect of apoptosis-related proteins and heat shock proteins upon BE's pathogenesis were also investigated by an immunohistochemical protocol. Results: Prevalence of BE was at 4.55% and the mean age of those affected was about 10 years older than for esophagitis. Typical reflux symptoms were significantly lower than with esophagitis, whereas signs of caspase-3 and HSP105 elevation were significantly higher. Expression of TERT, HSP70 and $HSP90{\alpha}$ in BE cases was significantly lower than in esophagitis. However, there was no statistical difference between the two groups in expression of HSP27. Conclusions: The prevalence of BE is high in Luoyang, which could result from esophagitis despite typical reflux symptoms being relatively uncommon. Initiation and development of BE might be the result of accelerated proliferation, apoptosis and differentiation of original cells to intestinal epithelium.
Design optimization and development of SMC composite tray
Cun-fei Wang,Zeng-fu Yang,Chengwang Shi,Xiaodong Li,Xu-feng Zhang 한양대학교 청정에너지연구소 2024 Journal of Ceramic Processing Research Vol.25 No.2
In the engineering application, trays are easy to break down to result in anchorage failure in the composite anchoring systems. Therefore, the research carried out the force analysis with mechanics of materials to observe the main stress concentration anddeformation of the tray. From the findings of the force analysis, the structure and key parameters of the tray were optimizedwith reference of the existing tray design. Besides, the study turns to the finite element software to simulate and analyze thetray. The results manifest that tray failure during the support mainly results from the expansion and deformation of the taperhole squeezed by the nut, which causes the tray taper hole to rupture and crackle extend, thus leading to its crack. What’smore, the tray breaks for the compression of the tray edge by the surrounding rock. The maximum deformation at the largeend of the optimized tray tapered hole was reduced from 33.8 mm to 4.7 mm, approximately 86% with the shear stress reducedfrom 781.67 Mpa to 258.83 Mpa, about 66.8%. Using Sheet Molding Compound (SMC) to mould trays with new structure andconducting the test of tray bearing capacity, it can be found that its bearing capacity is up to 250 KN. After the taper hole ofthe tray is locally strengthened, its bearing capacity is increased to 304 KN.
Zhang, Jie,Qi, Hui-Wei,Zheng, Hui,Chen, Mo,Zhu, Jun,Xie, Hui-Kang,Ni, Jian,Xu, Jian-Fang,Zhou, Cai-Cun Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.10
Background: The aim of this study was to evaluate the efficacy of alternating etoposide-cisplatin and vinorelbine-cisplatin (EP-NP) compared with an etoposide-cisplatin (EP) regimen for advanced combined small cell carcinomas. Materials and Methods: Histologically confirmed combined small cell carcinoma patients who met the inclusion criteria were randomly assigned (1:1) into either the EP-NP setting (group A) or the EP setting (group B). The primary endpoint was progression-free survival in patients who received at least one dose of treatment. Results: Eighty-two patients entered into this trial, 42 in group A and 40 in group B. The objective response rates in group A and group B were 42.9% and 32.5%, respectively (p=0.334). Survival analysis showed that median progression-free survival was 6.1 months in group A, which was significantly longer than the 4.1 months in group B (p=0.041). However, as to overall survival, no significant difference was found between the two groups (11.0 vs 10.1 months in groups A and B, respectively, p=0.545). No unexpected side effects were observed in either group. Conclusions: The EP-NP regimen for combined small cell carcinomas prolonged progressio-nfree survival compared with the EP regimen. Further clinical investigations are warranted.