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Journal of Materials Science & Technology 2015年第12期31卷 1217-1225页

作者： y.M.liu d.y.deng H.lei Z.l.Pei C.l.Jiang C.Sun J.Gong Institute of Metal Research Chinese Academy of Sciences

In the present study,WB 2（N） films are fabricated on silicon and yG8 substrates at different N 2 pressures by reactive magnetron *** influence of N 2 partial pressure（P （N2）） on the film microstructure and characteristics is studied systematically,including the chemical composition,crystalline structure,residual stress,surface roughness as well as the surface and the cross-section ***,nano-indentation and ball-on-disk tribometer are performed to analyze the mechanical and tribological properties of the *** results show that the addition of nitrogen apparently leads to the change of the structure from（1 0 1） to（0 0 1） orientation then to the amorphous structure with the formation of BN *** the addition of nitrogen can greatly refine the grain size and microstructure of the ***,the residual stress of the film is also found to change from tensile to compressive stress as a function of P （N2）,and the compressive stress increases with P （N2）,The WB 2（N） films with small nitrogen content,which are deposited at P （N2） of 0.004 and 0.006 Pa,exhibit better mechanical,tribological and corrosion properties than those of other *** increase of nitrogen content accelerates the formation of BN phase and fast decreases the film *** addition,the large N 2 partial pressure gives rise to the target poisoning accompanied by the increase of the target voltage and the decrease of the deposition rate.

关键词： Reactive magnetron sputtering Nanocomposites WB 2(N) films Residual stress Mechanical properties

THEORy OF WATER WAVES IN AN ElASTIC VESSEl

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Acta Mechanica Sinica 2000年第2期16卷 97-112页

作者： d. y. Hsieh division of Applied Mathematics Brown University USA

Recent experiments related to the dragon Wash phenomena showed that axisymmetric capillary waves appear first from excitation, and circumferential capillary waves appear after increase of the excitation strength. Based on this new finding, a theory of parametric resonance is developed in detail to explain the on- set of the prominent circumferential capillary waves. Numerical computation is also carried out and the results agree generally with the experiments. Analysis and nu- merical computation are also presented to explain the generation of axisymmetric low-frequency gravity waves by tile high-frequency external excitation.

关键词： water waves elastic vessel dragon Wash

A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAuRABH R.KIRAN d.SINGH R.VAISH V.S.CHAuHAN School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHSdT) of plates is employed to characterize the displacement field, with the incorporation of Green-lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATlAB environment to solve it numerically. Various helicoidal layup configurations including helicoidal recursive(HR), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(lH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

关键词： Inverse problems

Simulation of rainfall-runoff and watershed convergence process in the upper reaches of Heihe River Basin,July 2002

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Science China Earth Sciences 2004年第Z1期47卷 1-8页

作者： GAO yanhong l(u) Shihua CHENG Guodong Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The watershed flow concentration scheme in the distributed hydrology-soil- vegetation model (dHSVM) is coupled with the mesoscale atmospheric model MM5 version 3.5, in which the Oregen States university land surface model (OSulSM) was involved. The flood event which happened in July 2002 in the upper reaches of Heihe river basin is simulated and the surface flow convergence process is shown with this coupled model. It has been concluded that times water head reaches each place of the basin are different. Water amount at each point is split-flow proportionally as the drops in elevation between it and neighbor points. large part of the water amount pass away in greater slope direction and small part pass away in smaller slope *** of the slope convergence makes the atmospheric model redistributes the surface water laterally.

关键词： distributed hydrology-soil-vegetation model, mesoscale atmospheric model, watershed flow concentration process.

Chronic constipation in hemiplegic patients

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World Journal of Gastroenterology 2007年第29期13卷 3967-3972页

作者： F Bracci d Badiali P Pezzotti G Scivoletto u Fuoco l di lucente A Petrelli E Corazziari department of Clinical Sciences La Sapienza University Rome Italy ISS Ministry of Health Rome Italy IRCCS Foundation Santa lucia Rome Italy

AIM: To assess the prevalence of bowel dysfunction in hemiplegic patients, and its relationship with the site of neurological lesion, physical immobilization and pharmacotherapy. METHOdS: Ninety consecutive hemiplegic patients and 81 consecutive orthopedic patients were investigated during physical motor rehabilitation in the same period, in the same center and on the same diet. All subjects were interviewed ≥ 3 mo after injury using a questionnaire inquiring about bowel habits before injury and at the time of the interview. Patients’ mobility was evaluated by the Adapted Patient Evaluation Conference System. drugs considered for the analysis were nitrates, angiogenic converting enzyme (ACE) inhibitors, calcium antagonists, anticoagulants, antithrombotics, antidepressants, anti-epileptics. RESulTS: Mobility scores were similar in the two groups. de novo constipation (OR = 5.36) was a frequent outcome of the neurological accident. Hemiplegics showed an increased risk of straining at stool (OR: 4.33), reduced call to evacuate (OR: 4.13), sensation of incomplete evacuation (OR: 3.69), use of laxatives (OR: 3.75). logistic regression model showed that constipation was significantly and independently associated with hemiplegia. A positive association was found between constipation and use of nitrates and antithrombotics in both groups. Constipation was not related to the site of brain injury. CONCluSION: Chronic constipation is a possible outcome of cerebrovascular accidents occurring in 30% of neurologically stabilized hemiplegic patients. Its onset after a cerebrovascular accident appears to be independent from the injured brain hemisphere, and unrelated to physical inactivity. Pharmacological treatment with nitrates and antithrombotics may represent an independent risk factor for developing chronic constipation.

关键词： Constipation disphagia Stroke Pharmacotherapy

Implications of crude oil pollution on natural regeneration of plant species in an oil-producing community in the Niger delta Region of Nigeria

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Journal of Forestry Research 2014年第4期25卷 915-921页

作者： u.d Chima G.Vure department of Forestry and Wildlife Management University of Port Harcourt- Choba P.M.B. 5323 Port Harcourt Rivers State Nigeria

The study evaluated the impact of crude oil pollution on natu- ral regeneration of plant species in a major oil-producing community in the Niger delta region of Nigeria. Three sites--unpolluted site （uS）, polluted and untreated site （PuS）, and polluted and treated site （PTS）-- were purposively chosen for the study. The seedling emergence method was used to evaluate soil seed banks in the various sites at two depths, 0 to 10 cm and 10 to 20 cm. Woody-plant species richness, abundance, and diversity were higher in the uS seed bank than in the PuS and PTS seed banks. The highest number of non-woody plants was observed in the uS, followed by the PTS, and then the PuS. Both species richness and diversity of non-woody plants were highest at the uS, followed by the PuS, and lowest in the PTS. Woody species in the uS seed bank were 87.5% and 80% dissimilar with those of the PuS and PTS at 0-10 cm and 10--20 cm respectively. No variation was observed between woody species in the PuS and PTS seed banks. Non-woody species at 0-10 em uS seed bank were 73.08% dissimilar with those of PuS at the two soil depths and 81.48/88.46% dissimilar with those of the 0-10/10-20 cm of the PTS respectively. At 10-20 cm, non-woody species of theuS were 69.66% dissimilar with those from each of the two soil depths in PuS; and 73.91/81.82% dissimilar with those of 0-10/10-20 cm of the PTS respectively. Non-woody species variation between the PuS and PTS was higher at 10-20 cm than 0-10 cm. The poor seed bank attributes at the polluted sites demonstrates that crude oil pollution negatively af- fected the natural regeneration potential of the native flora because soil seed banks serve as the building blocks for plant succession. Thorough remediation and enrichment planting are recommended to support the recovery process of vegetation in the polluted areas.

关键词： Ogoni land crude oil pollution remediation plant regeneration

Annual and seasonal changes of the air temperature with altitude in the upper dades valley, High Atlas, Morocco

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Journal of Mountain Science 2022年第1期19卷 85-102页

作者： ŻMudZKA Elwira dŁuŻEWSKI Maciej dĄBSKI Maciej lEZIAK Kamil ROJAN Elżbieta department of Climatology Faculty of Geography and Regional StudiesUniversity of WarsawKrakowskie Przedmieście 3000-927 WarsawPoland department of Geomorphology Faculty of Geography and Regional StudiesUniversity of WarsawKrakowskie Przedmieście 3000-927 WarsawPoland

The purpose of this study is to determine the size of air temperature changes with altitude in the mountains of the arid zone, on the example of the upper dades valley(High Atlas, Morocco). The air temperature change with altitude was determined on the basis of 5 years data from three meteorological stations. The analysis was carried out on an annual and seasonal basis. The annual and daily variations of thermal gradients between pairs of stations were also determined. It was found that the average thermal gradient in the upper dades valley was-1.02℃ per 100 m. The highest values of the thermal gradient occur in winter and the lowest in summer. In winter,the thermal gradient was characterized by the greatest variability. Minima of the daily variation of air temperature gradients were observed in early morning hours and maxima around midday. In the lower part of the valley, air temperature inversion frequently developed between 10 AM and 3 PM *** obtained results show high thermal gradients in the mountains of the arid zone, with their annual amplitude increasing in the lower parts of the *** instantaneous values of the gradients were significantly modified by the supply of latent heat and the occurrence of dust storms. It has been shown that the advection factor plays an important role in shaping large gradient values. The study contains novel results of thermal gradient measurements in high mountains of arid zone.

关键词： Air temperature gradient Thermal inversion Annual and seasonal variability Synoptic situation High mountains of arid zone High Atlas Mountains

Influence of Co Content on Raman and Photoluminescence Spectra of Co doped ZnO Nanowires

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Journal of Materials Science & Technology 2012年第4期28卷 313-316页

作者： y.Q. Chang P.W. Wang S.l. Ni y. long X.d. li School of Materials Science anti Engineering University of Science and Technology Beijing Beijing 100083 China department of Physics National Key Laboratory of Mesoscopic Physics Peking University Beijing 100871 China

Co doped ZnO nanowires with different Co contents have been fabricated by a chemical vapor deposition method. X-ray diffraction results show that all the samples are of single phase and crystallize in wurtzite ZnO structure. The lattice parameter a increases with increasing Co content, while the parameter c has no obvious change with increasing Co. Raman spectra show that the nonpolar E2（High） mode becomes broad and weak with the doping of Co, which indicates that the incorporation of Co causes structural disorder in the crystalline columnar ZnO lattice. The photolurninescence spectra exhibit that the position of the ultraviolet emission shifts to short wavelength and the intensity decreases with increasing Co. The green emission is affected by two contrary factors. It is increased by the introduced defects, but suppressed by the interaction between Co doping and native defects and the later affects it more significantly.

关键词： Co doped ZnO nanowires Raman Photoluminescence Single phase

Advancements in liver Tumor detection:A Comprehensive Review of Various deep learning Models

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 91-122页

作者： Shanmugasundaram Hariharan d.Anandan Murugaperumal Krishnamoorthy Vinay Kukreja Nitin Goyal Shih-yu Chen deptartment of Artificial Intelligence and data Science Vardhaman College of EngineeringHyderabad501218India deptartment of CSE V.S.B College of EngineeringKarur639111India deptartment of Electrical and Electronics Engineering Vardhaman College of EngineeringHyderabad501218India Centre for Research Impact&Outcome Chitkara UniversityRajpura140401PunjabIndia department of Computer Science and Engineering School of Engineering and TechnologyCentral University of HaryanaMahendergarh123031HaryanaIndia department of Computer Science and Information Engineering National Yunlin University of Science and TechnologyYunlin64002Taiwan Intelligence Recognition Industry Service Research Center National Yunlin University of Science and TechnologyYunlin64002Taiwan

liver cancer remains a leading cause of mortality worldwide,and precise diagnostic tools are essential for effective treatment *** Tumors(lTs)vary significantly in size,shape,and location,and can present with tissues of similar intensities,making automatically segmenting and classifying lTs from abdominal tomography images crucial and *** review examines recent advancements in liver Segmentation(lS)and Tumor Segmentation(TS)algorithms,highlighting their strengths and limitations regarding precision,automation,and *** metrics are utilized to assess key detection algorithms and analytical methods,emphasizing their effectiveness and relevance in clinical *** review also addresses ongoing challenges in liver tumor segmentation and identification,such as managing high variability in patient data and ensuring robustness across different imaging *** suggests directions for future research,with insights into technological advancements that can enhance surgical planning and diagnostic accuracy by comparing popular *** paper contributes to a comprehensive understanding of current liver tumor detection techniques,provides a roadmap for future innovations,and improves diagnostic and therapeutic outcomes for liver cancer by integrating recent progress with remaining challenges.

关键词： liver tumor detection liver tumor segmentation image processing liver tumor diagnosis feature extraction tumor classification deep learning machine learning

The dimension split element-free Galerkin method for three-dimensional potential problems

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Acta Mechanica Sinica 2018年第3期34卷 462-474页

作者： Z.J.Meng H.Cheng l.d.Ma y.M.Cheng Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University School of Applied Science Taiyuan University of Science and Technology department of Civil Engineering Shanghai University School of Materials Science and Engineering Taiyuan University of Science and Technology

This paper presents the dimension split element-free Galerkin （dSEFG） method for three-dimensional potential problems, and the corresponding formulae are obtained. The main idea of the dSEFG method is that a three-dimensional potential problem can be transformed into a series of two-dimensional problems. For these two-dimensional problems, the improved moving least-squares （IMlS） approximation is applied to construct the shape function, which uses an orthogonal function system with a weight function as the basis functions. The Galerkin weak form is applied to obtain a discretized system equation, and the penalty method is employed to impose the essential boundary condition. The finite difference method is selected in the splitting direction. For the purposes of demonstration, some selected numerical examples are solved using the dSEFG method. The convergence study and error analysis of the dSEFG method are presented. The numerical examples show that the dSEFG method has greater computational precision and computational efficiency than the IEFG method.

关键词： dimension split method Improved moving least-squares (IMlS) approximation Improved element-free Galerkin (IEFG) method Finite difference method (FdM) dimension split element-free Galerkin (dSEFG) method Potential problem