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Electron Raman scattering in semiconductor quantum well wire of cylindrical ring geometry

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Chinese Physics B 2015年第11期24卷 442-447页

作者： Re.betancourt-riera ri.betancourt-riera J.M.Nieto Jalil R.riera Instituto Tecnol ógico de Hermosillo.Avenida Tecnol ógico S/N Col.Sahuaro Departamento de Investigaci ón en Física Universidad de Sonora Tecnol ógico de Monterrey-Campus Sonora Norte.Bulevar Enrique Mazón López No.965

We study the electron states and the differential cross section for an electron Raman scattering process in a semi- conductor quantum well wire of cylindrical ring geometry. The electron Raman scattering developed here can be used to provide direct information about the electron band structures of these confinement systems. We assume that the system grows in a GaAs/Al0.35Ga0.65As matrix. The system is modeled by considering T = 0 K and also a single parabolic con- duction band, which is split into a sub-band system due to the confinement. The emission spectra are discussed for different scattering configurations, and the selection rules for the processes are also studied. Singularities in the spectra are found and interpreted.

关键词： electron states Raman scattering selection rules quantum well wires

低空经济助推新质生产力的运行机理与路径选择

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新疆师范大学学报（哲学社会科学版） 2025年第1期46卷 118-131页

作者：欧阳日辉中央财经大学中国互联网经济研究院北京100081

低空经济是以低空飞行活动为牵引,以有人驾驶和无人驾驶航空器为主要载体,通过技术创新和模式创新推动相关产业融合发展的新型综合性经济形态。低空经济涉及领域和行业多、应用场景多、创新之处多、产业链条长、带动效应强,具有创新驱... 详细信息

低空经济是以低空飞行活动为牵引,以有人驾驶和无人驾驶航空器为主要载体,通过技术创新和模式创新推动相关产业融合发展的新型综合性经济形态。低空经济涉及领域和行业多、应用场景多、创新之处多、产业链条长、带动效应强,具有创新驱动性、空间依赖性、跨界融合性、辐射带动性等技术—经济特征。低空经济通过场景牵引、跨界融合、协同治理,聚焦应用场景,打造低空多场景应用,推动“低空+”物流配送、“低空+”城市空中交通、“低空+”旅游、“低空+”应急救援等规模化发展,在技术创新与制度创新相互嵌套、协同治理的基础上实现健康发展。当前,各地各部门积极抢占低空经济新赛道,通过建设智能互联高效的基础设施、加快低空智能互联航行技术创新、完善产业链增强低空产业韧性和安全等举措因地制宜打造融合创新的应用场景。为促进低空经济发展,应加强产业政策引导与支持,支持低空经济技术创新与研发,推动跨界融合与应用场景创新,完善产业链配套服务体系。

关键词：低空经济新质生产力应用场景科技创新产业创新

Assessing cooling energy reduction potentials by retrofitting traditional cavity walls into passively ventilated cavity walls

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Building Simulation 2021年第4期14卷 1295-1309页

作者： ri Na Zhigang Shen Department of Civil and Environmental Engineering University of DelawareNewarkDE19716USA The Durham School of Architecture Engineering and Construction University of Nebraska LincolnLincolnNE68588USA

A major roadblock in achieving substantial building energy reduction is the low performance of old buildings that account for a significant portion of the building energy *** low-cost energy retrofit solutions that do not disrupt occupants’daily life during the retrofitting is the key to successful building energy retrofit *** this paper,a novel and low-cost exterior wall retrofitting solution is introduced,and its performance in reducing space cooling load was quantitatively evaluated to demonstrate its feasibility and *** primary goal of this paper is to provide a quantitative assessment of the cooling-energy savings potential by using the proposed new wall *** intended retrofitting targets are the large amount of existing cavity-wall buildings located in hot climate *** quantification of the before-after heat-flux reduction was conducted through a 3-dimensional steady-state low turbulence computational fluid dynamics(CFD)model,which is validated by benchmarking its prediction against the published experimental case *** outcomes of the investigation suggest that this simple low-cost solution has great potentials in reducing buildings’summer cooling load in hot climate *** applicability of this solution is not limited to retrofitting existing *** energy-efficient building designs can also adopt this solution in their envelope systems.

关键词： low-cost energy retrofit building envelope cavity wall stack effect space cooling energy reduction CFD

A Remark on Leray's Problem on Stationary Navier–Stokes Flows with Large Fluxes in Infinite Cylindrical Domains

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Acta Mathematica Sinica,English Series 2015年第10期31卷 1571-1581页

作者： Myong-Hwan ri Institute of Mathematics State Academy of SciencesPyongyang DPR Korea

We consider Leray＇s problem on stationary Navier Stokes flows with arbitrary large fluxes in an unbounded cylinder with several exits to infinity. For a stationary Navier Stokes flow with large fluxes in the unbounded cylinder, we prove that, if the difference between the pressure of the main flow and the pressure of the Poiseuille flow with the same flux in a branch of the cylinder remains bounded at ｜x｜→∞, then the flow behaves at infinity of the branch like the Poiseuille flow.

关键词： Leray's problem Navier-Stokes equations large flux unbounded cylindrical domains

Comparative study of omeprazole, lansoprazole, pantoprazole and esomeprazole for symptom relief in patients with reflux esophagitis

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World Journal of Gastroenterology 2009年第8期15卷 990-995页

作者： ri-Nan Zheng Hainan Medical College 31 Longhua Road Haikou 57102 Hainan Proince China

AIM: To clarify whether there is any difference in the symptom relief in patients with reflux esophagitis following the administration of four Proton pump inhibitors (PPIs). METHODS: Two hundred and seventy-four patients with erosive reflux esophagitis were randomized to receive 8 wk of 20 mg omeprazole (n = 68), 30 mg of lansoprazole (n = 69), 40 mg of pantoprazole (n = 69), 40 mg of esomeprazole (n = 68) once a day in the morning. Daily changes in heartburn and acid reflux symptoms in the first 7 d of administration were assessed using a six-point scale (0: none; 1: mild; 2: mild-moderate; 3: moderate; 4: moderate-severe; 5: severe). RESULTS: The mean heartburn score in patients treated with esomeprazole more rapidly decreased than those receiving other PPI. Complete resolution of heartburn was also more rapid in patients treated with esomeprazole for 5 d compared with omeprazole (P = 0.0018, P = 0.0098, P = 0.0027, P = 0.0137, P = 0.0069, respectively), lansoprazole (P = 0.0020, P = 0.0046, P = 0.0037, P = 0.0016, P = 0.0076, respectively), and pantoprazole (P = 0.0006, P = 0.0005, P = 0.0009, P = 0.0031, P = 0.0119, respectively). There were no significant differences between the four groups in the rate of endoscopic healing of reflux esophagitis at week 8. CONCLUSION: Esomeprazole may be more effective than omeprazole, lansoprazole, and pantoprazole for the rapid relief of heartburn symptoms and acid reflux symptoms in patients with reflux esophagitis.

关键词： Omeprazole Pantoprazole Lansoprazole Esomeprazole Reflux esophagitis Symptom relief

Regularity for 3D Navier–Stokes Equations Based on Energy Distribution at Wavenumber Bands

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Acta Mathematica Sinica,English Series 2019年第8期35卷 1377-1392页

作者： Myong-Hwan ri Institute of Mathematics State Academy of SciencesDPR Korea

We present some regularity criteria for the Leray–Hopf weak solutions to the Cauchy problem for 3D Navier–Stokes equations based on energy distribution at wavenumber bands. We show sufficient conditions for regularity based on the ratios of energy dissipation rates at sufficiently high wavenumber bands and neighboring medium wavenumber bands. Moreover, we give a regularity criterion based on relations between energy at high and low wavenumber bands.

关键词： Navier-Stokes equations global regularity energy transfer

First-principles simulation and experimental evidence for improvement of transmittance in ZnO films

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Progress in Natural Science:Materials International 2011年第1期21卷 40-45页

作者： ri-ichi MURAKAMI Department of Mechanical Engineering The University of Tokushima2-1 Minamijosanjima-choTokushima 770-8506Japan

ZnO/Ag/Glass films were prepared by a DC magnetron sputtering system,which exhibit both excellent properties of high conductivity and high ***,an enhancement of transmission of ZnO films was observed after brought into contact to a silver layer,but the understanding of experimental findings for the enhancement of transmission was ***,the first-principles simulations of electrical and optical properties were utilized using the density functional theory with local-density approximations or generalized-gradient *** crystal structure of ZnO or Ag was imported from the Material Studio *** periodic supercell has the same atomic ratio with the experimental structure and was optimized using the CASTEP package in Material *** to the calculation results,the enhancement in transmission is attributed to the surface plasmon polariton in the asymmetric structure films.

关键词： first-principles transparent conductive oxide ZnO transmittance surface plasmon polaritons

Cosmological constraints on the background dynamics of a two-field nonsingular bounce model

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Chinese Physics C 2024年第11期48卷 149-155页

作者： Kang Song ri Sin Chol Hwang Hyon Chol ri Department of Physics Kim Il Sung UniversityRyongnam DongTaesong District PyongyangDemocratic People's Republic of Korea

In this study,we consider a nonsingular two-field bounce scenario with non-minimal kinetic coupling between two scalar *** derive constraints on the model parameters from the finiteness of the physical quantities at the classical level and from the relation between the late-time accelerated expansion and particle production up to the bounce *** then determine the allowed parameter space for the model.

关键词： bounce universe parameter space

A novel weld-pool-length monitoring method based on pixel analysis in plasma arc additive manufacturing

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Advances in Manufacturing 2024年第2期12卷 335-348页

作者： Bao-ri Zhang Yong-Hua Shi Bionic Robot Research Department Ji Hua LaboratoryFoshan528200GuangdongPeople’s Republic of China Guangdong Provincial Engineering Research Center for Special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640People’s Republic of China

The real-time monitoring of the weld pool during deposition is important for automatic control in plasma arc additive *** obtain a high deposition accuracy,it is essential to maintain a stable weld pool *** this study,a novel passive visual method is proposed to measure the weld pool *** the proposed method,the image quality was improved by designing a special visual system that employed an endoscope and a *** also includes pixel brightness-based and gradient-based algorithms that can adaptively detect feature points at the boundary when the weld pool geometry *** algorithm can also be applied to materials with different solidification *** was performed to measure the real weld pool length in world coordinates,and outlier rejection was performed to increase the accuracy of the ***,tests were carried out on the intersection component,and the results showed that the proposed method performed well in tracking the changing weld pool length and was applicable to the real-time monitoring of different types of materials.

关键词： Plasma arc additive manufacturing(PAAM) Weld pool geometry Gradient analysis Real-time detection