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EEFA： Energy Efficiency Frame Aggregation Scheduling Algorithm for IEEE 802.11n Wireless Network

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China Communications 2014年第3期11卷 19-26页

作者： GE Zhihui liANG anzhong li Taoshen School of Computer Electronics and Information Guangxi University Guangxi Nanning 530004 P. R. China

Packet size is restricted due to the error-prone wireless channel which drops the network energy utilization. Furthermore, the frequent packet retransmissions also lead to energy waste. In order to improve the energy efficiency of wireless networks and save the energy of wireless devices, EEFA （Energy Efficiency Frame Aggregation）, a frame aggregation based energy-efficient scheduling algorithm for IEEE 802.11n wireless network, is proposed. EEFA changes the size of aggregated frame dynamically according to the frame error rate, so as to ensure the data transmission and retransmissions completed during the TXOP and reduce energy consumption of channel contention. NS2 simulation results show that EEFA algorithm achieves better performance than the original frame-aggregation algorithm.

关键词： WLAN energy efficiency packet size frame aggregation IEEE802.1 ln retransmission

On the improved dynamics approach in loop quantum black holes

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Communications in Theoretical Physics 2024年第3期76卷 138-143页

作者： Hongchao Zhang Wen-Cong Gan Yungui Gong anzhong Wang Institute for Theoretical Physics&Cosmology Zhejiang University of TechnologyHangzhou310023China United Center for Gravitational Wave Physics(UCGWP) Zhejiang University of TechnologyHangzhou310023China College of Physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022China GCAP-CASPER Physics DepartmentBaylor UniversityWacoTX 76798-7316United States of America School of Physics Huazhong University of Science and TechnologyWuhanHubei 430074China Department of Physics School of Physical Science and TechnologyNingbo UniversityNingboZhejiang 315211China

In this paper,we consider the B?hmer–Vandersloot(BV)model of loop quantum black holes obtained from the improved dynamics *** adopt the Saini–Singh gauge,in which it was found analytically that the BV spacetime is geodesically *** show that black/white hole horizons do not exist in this geodesically complete ***,there exists only an infinite number of transition surfaces,which always separate trapped regions from anti-trapped *** on the improved dynamics approach adopted in other models of loop quantum black holes are also given.

关键词： loop quantum gravity black hole dynamics approach

A regular MOG black hole's impact on shadows and gravitational weak lensing in the presence of a quintessence field

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Communications in Theoretical Physics 2024年第8期76卷 91-102页

作者： Ahmad Al-Badawi Sanjar Shaymatov Mirzabek Alloqulov anzhong Wang Department of Physics Al-Hussein Bin Talal UniversityPO Box:2071111Ma’anJordan Institute for Theoretical Physics and Cosmology Zhejiang University of TechnologyHangzhou 310023China Tashkent State Technical University Tashkent 100095Uzbekistan University of Tashkent for Applied Sciences Str.Gavhar 1Tashkent 100149Uzbekistan New Uzbekistan University Movarounnahr Street 1Tashkent 100000Uzbekistan Institute of Fundamental and Applied Research National Research University TIIAMEKori Niyoziy 39Tashkent 100000Uzbekistan GCAP-CASPER Physics DepartmentBaylor UniversityWacoTX 76798-7316United States of America

We investigate the impact of the modified gravity(MOG)field and the quintessence scalar field on horizon evolution,black hole(BH)shadow and the weak gravitational lensing around a static spherically symmetric *** first begin to write the BH metric associated with the MOG parameter and quintessence scalar *** then determine the BH shadow and obtain numerical solutions for the photon sphere and shadow *** show that the MOG(α)and the quintessence(c)parameters have a significant impact on the BH shadow and photon *** on the analysis,we further show that the combined effects of the MOG parameter and quintessence field can increase the values of BH shadow and photon sphere *** also obtain constraints on the BH parameters by applying the observational data of Sgr A^(★)and M87^(★).Finally,we consider the weak deflection angle of BH within the context of the Gauss-Bonnet theorem(GBT)and show that the combined effects of the MOG and quintessence parameters do make the value of the deflection angle increase,and find this remarkable property is in good agreement with the physical meaning of both parameters that can maintain the strong gravitational field in the surrounding environment of a BH.

关键词： modified gravity shadows gravitational weak lensing quintessence field

Nonexistence of quantum black and white hole horizons in an improved dynamic approach

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 56-73页

作者： Wen-Cong Gan Xiao-Mei Kuang Zhen-Hao Yang Yungui Gong anzhong Wang Bin Wang College of Physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022China GCAP-CASPER Physics DepartmentBaylor UniversityWaco 76798-7316USA Institute for Theoretical Physics&Cosmology Zhejiang University of TechnologyHangzhou 310023China United Center for Gravitational Wave Physics(UCGWP) Zhejiang University of TechnologyHangzhou 310023China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China Department of Physics School of Physical Science and TechnologyNingbo UniversityNingbo 315211China School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

In this paper,we study the quantum geometric effects near the locations where classical black hole horizons used to appear in Einstein's classical theory,within the framework of an improved dynamic approach,in which the internal region of a black hole is modeled by the Kantowski-Sachs(KS)spacetime and the two polymerization parameters are functions of the phase space *** detailed analysis shows that the effects are so strong that black and white hole horizons of the effective quantum theory do not exist at all and instead are replaced by transition surfaces,across which the metric coefficients and their inverses are smooth and remain finite,as are the corresponding curvatures,including the Kretschmann *** surfaces always separate trapped regions from anti-trapped *** number of such surfaces is infinite,so the corresponding KS spacetimes become geodesically complete,and no black and white hole-like structures exist in this scheme.

关键词： canonical quantization loop quantum gravity quantum aspects of black holes

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腹腔镜治疗疑难复杂阑尾炎的安全性和可行性分析

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中国现代医生 2019年第11期57卷 60-62页

作者：李安忠新疆维吾尔自治区塔城市人民医院普外科

目的分析腹腔镜治疗疑难复杂阑尾炎的安全性和可行性。方法随机选取2016年8月~2018年8月我院普外科疑难复杂阑尾炎患者60例,随机分为腹腔镜手术组(30例)与传统开放手术组(30例)两组,观察两组患者的手术相关指标、VAS评分、术后并发症发... 详细信息

目的分析腹腔镜治疗疑难复杂阑尾炎的安全性和可行性。方法随机选取2016年8月~2018年8月我院普外科疑难复杂阑尾炎患者60例,随机分为腹腔镜手术组(30例)与传统开放手术组(30例)两组,观察两组患者的手术相关指标、VAS评分、术后并发症发生情况。结果腹腔镜手术组患者的住院费用为(15425.3±2000.6)元,显著高于传统开放手术组的(7235.6±1200.5)元(P<0.05),腹腔镜手术组肠蠕动恢复时间、进食时间、住院时间均显著短于传统开放手术组(P<0.05),手术后VAS评分显著低于传统开放手术组(P<0.05)。腹腔镜手术组患者的术后并发症发生率为16.7%(5/30),显著低于传统开放手术组的53.3%(16/30)(P<0.05)。结论腹腔镜手术治疗疑难复杂阑尾炎较传统开放手术具有较高的安全性和可行性,值得临床推广。

关键词：腹腔镜疑难复杂阑尾炎安全性可行性

基于性态设计的抗弯钢框架与钢框架-钢板剪力墙结构性能对比分析

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钢结构 2015年第9期30卷 18-22,11页

作者：陈永昌李建中西安建筑科技大学建筑设计研究院西安710055 宁波职业技术学院浙江宁波315800

抗弯钢框架和钢框架-钢板剪力墙结构的耗能构件分别为框架梁和内填钢板,现行规范基于强度设计理论,不能保证结构的整体破坏模式。近年来,国内外学者提出了钢结构基于性态的塑性设计方法,使得同等设计条件下,二者同时达到性能目标。依据... 详细信息

抗弯钢框架和钢框架-钢板剪力墙结构的耗能构件分别为框架梁和内填钢板,现行规范基于强度设计理论,不能保证结构的整体破坏模式。近年来,国内外学者提出了钢结构基于性态的塑性设计方法,使得同等设计条件下,二者同时达到性能目标。依据基于性态的设计方法设计了5层、10层及15层抗弯钢框架和钢框架-钢板剪力墙结构。通过SAP 2000建立平面分析模型,对结构进行Pushover分析和非线性时程分析,对比分析两种结构的承载力、抗侧刚度、延性指标、破坏模式以及层间侧移分布状态。对比结果表明:钢框架-钢板剪力墙结构具有较高的承载力和抗侧刚度,层间侧移较小,抗弯钢框架延性较好。

关键词：抗弯钢框架钢框架-钢板剪力墙性能目标

大型水利枢纽蓄水后不同时期对下游河床变化的影响

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水利学报 1999年第3期30卷 38-43页

作者：李安中河海大学

本文通过闽江水口水库下游４６ｋｍ以下的竹岐至马尾河段和汉江丹江口水库以下１１７ｋｍ的襄樊至河口河段的演变分析与模型试验，论述了水库对下游河道变化的影响．

关键词：河床演变水利枢纽水库下游河道

Semi-automated detection of rangeland runoff and erosion control berms using high-resolution topography data

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International Soil and Water Conservation Research 2024年第1期12卷 217-226页

作者： li li Changjiang River Scientific Research Institute of Changjiang Water Resources Commission Wuhan430010China Research Center on Mountain Torrent&Geologic Disaster Prevention Ministry of Water ResourcesWuhan430010China University of Arizona School of Natural Resources and the EnvironmentTucsonAZ85719USA

An inventory of topographic modifications is essential to addressing their impacts on hydrological and morphological processes in human-altered ***,such inventories are generally *** study presents two workflows for semi-automatic detection of linear earthen runoff and erosion control berms in rangelands using high-resolution topographic *** workflows consist of initial object identification by applying either morphological grayscale reconstruction(MGR)or the Geomorphon(GEO)method,followed by identification refinements through filters based on objects’horizontal and vertical *** sites were selected within the Altar Valley,Arizona,in the southwestern United *** site was used for developing workflows and optimizing filter thresholds,and the other two sites were used to validate *** results showed that:1)The MGR-based workflow methodology could produce final precision and detection rates of up to 92%and 75%,respectively,and take less than 5 s for a 10.1 km^(2) site;2)The workflow based on the MGR method yielded greater identification accuracy than did the GEO workflow;3)Object length,orientation,and eccentricity were important characteristics for identifying earthen berms,and are sensitive to general channel flow direction and berm shape;4)Manual interrogation of topographic data and imagery can significantly improve identification precision *** proposed workflows will be useful for developing inventories of runoff and erosion control structures in support of sustainable rangeland management.

关键词： Earthen berm Rangeland Grayscale morphological reconstruction Geomorphon liDAR

Effects of mid-passage gap with a variable surface angle on a turbine vane endwall’s aerothermal and film cooling performances

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Chinese Journal of Aeronautics 2024年第6期37卷 20-37页

作者： Zhiyu li Kaiyuan ZHANG Zhigang li Jun li Institute of Turbomachinery Xi’an Jiaotong UniversityXi’an 710049China

The mid-passage gap is an inevitable structure in a vane passage due to turbine vanes being manufactured *** coolant from this gap is able to prevent hot mainstream ingression and provide cooling protection for the endwall.A novel idea of enlarging the endwall’s coverage area and reducing the endwall’s thermal load by applying the mid-passage gap with variable surface angles is carried out in this *** endwall’s aerothermal and film cooling performances under four mid-passage gap modes at three typical mass flow ratio conditions are numerically *** indicate that under the traditional mid-passage mode,the coolant flows into the mainstream with a perpendicular incidence angle and can’t stick to the ***,cooling failure occurs,and the endwall’s thermal load is badly *** film cooling level at the suction-side endwall is improved when applying the mid-passage gap of a 45surface angle due to the secondary vortex being *** addition,when applying the mid-passage gap of a 135surface angle,the horseshoe vortex is pushed away,and the coverage area at the pressure-side endwall is enlarged *** best film cooling performance is achieved when the upstream surface angle is 135and the downstream surface angle is 45due to the adiabatic film cooling effectiveness being increased at both the pressure-and suction-side *** the mass flow ratio is 1.5%,the coverage area is enlarged by 43%,and the area-averaged adiabatic film cooling effectiveness is increased by 37%,when compared with those under the traditional mid-passage mode.

关键词： Film cooling Heat transfer Surface angle Mid-passagegap Turbinevane endwall