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Analyzing dynamic curve widening on forest roads

Journal of Forestry Research 2017年第2期28卷 411-417页

作者： Mustafa Akgul Murat Demir Abdullah e.Akay Forest engineering Division Faculty of ForestryForest Construction and TransportationIstanbul UniversitySariyerIstanbulTurkey Forest engineering Department Faculty of ForestryBursa Technical UniversityOsmangazi16200 BursaTurkey

Forest roads require important design specifications to ensure all-season access for various vehicles. Long and heavy log trucks can face serious maneuvering problems on forest roads due to insufficient amount of area to the left for road widening on horizontal curves. In order to provide safe and continuous shipment and transportation,appropriate curve widening areas should be provided for long vehicles along horizontal curves. In this study, a statistical model was developed to provide curve-widening solutions for long trucks（e.g., those with 18 wheels） considering various curve radius and deflection angles. The dynamic curve widening feature of Plateia 2013 program was employed to calculate curve widening for the specified vehicle. During the solution process, nine different horizontal curve diameters from 10 to 50 m（by 5 m intervals）and 17 different deflection angles from 90° to 170°（by 5°intervals） were evaluated to run horizontal curve-widening analysis. Using a multiple regression model, we made suitable predictions about curve widening. The curvewidening areas decrease as the horizontal curve radius increases, while increasing the deflection angle on horizontal curves increases curve widening areas. Clearly, the computer-based dynamic curve widening model developed in this study can be effectively used in determining optimum widening for horizontal curves by evaluating the number of alternatives that fit geometrical specifications and vehicle types.

关键词： deflection diameters radius specifications transportation alternatives determining evaluating insufficient season

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evolving Neural Network Using variable String Genetic Algorithm for Color Infrared Aerial Image Classification

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Chinese Geographical Science 2008年第2期18卷 162-170页

作者： FU Xiaoyang P e R Dale ZHANG Shuqing Institute of Computer and Science Technology Jilin University Zhuhai 519041 China Griffith Sehool of environment Griffith University Queensland 4111 Australia Northeast Institute of Geography and Agroeeology Chinese Aeademy of Seienees Changehun 130012 China

Coastal wetlands are characterized by complex patterns both in their geomorphlc and ecological teatures. Besides field observations, it is necessary to analyze the land cover of wetlands through the color infrared （CIR） aerial photography or remote sensing image. In this paper, we designed an evolving neural network classifier using variable string genetic algorithm （vGA） for the land cover classification of CIR aerial image. With the vGA, the classifier that we designed is able to evolve automatically the appropriate number of hidden nodes for modeling the neural network topology optimally and to find a near-optimal set of connection weights globally. Then, with backpropagation algorithm （BP）, it can find the best connection weights. The vGA-BP classifier, which is derived from hybrid algorithms mentioned above, is demonstrated on CIR images classification effectively. Compared with standard classifiers, such as Bayes maximum-likelihood classifier, vGA classifier and BP-MLP （multi-layer perception） classifier, it has shown that the vGA-BP classifier can have better performance on highly resolution land cover classification.

关键词： variable string genetic algorithm neural network pattern classification CIR image

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Resolution enhancement of Optical Surface Plasmon Resonance Sensor Using Metamaterial

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Photonic Sensors 2015年第4期5卷 330-338页

作者： Sarika PAL Y. K. PRAJAPATI J. P. SAINI v. SINGH Sarika Pal Department of Electronics & Communication Engineering KIET Ghaziabad (U.P.) India yogendra Kumar Prajapati Department of Electronics & Communication Engineering MNNIT Allahabad-211004 (U.P.) India jai Prakash Saini Department of Electronics & Communication Engineering BIET Jhansi-284128 (U.P.) India vivek Singh Department of Physics Faculty of Science Banaras Hindu University Varanasi (U.P.) India

In this paper, we present and discuss a an optical surface plasmon resonance （SPR） path to extend the enhancement of the resolution of sensor. Basically, our approach is to combine bi-metamaterial layers to design the SPR sensor. The calculation shows that the proposed SPR sensor structure has a preference over the conventional SPR sensors and bimetallic SPR sensors since it gives a much sharper reflectance dip and can achieve considerable sensitivity improvement when compared to the recently reported investigations. The effects of the metamaterial permittivity, permeability, and thickness on the reflectance curve are studied. It is also seen that metamaterial layers improve the field of the proposed SPR structure, which may provide a novel tool to significantly enhance the sensitivity and resolution of the sensors.

关键词： Surface plasmon resonance sensor metamaterials Fresnel equations reflectance

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Transcanal endoscopic excision of tympanic paraganglioma: A three-case series

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Laparoscopic, endoscopic and Robotic Surgery 2020年第4期3卷 126-130页

作者： Satish Nair K.v.R.Brijith J.G.Aishwarya v.Pavithra Department of eNT-HNS Apollo HospitalsBannerghatta RoadBangaloreKarnataka560076India

Paragangliomas are rare neuroendocrine tumors that arise in sympathetic and parasympathetic paraganglion system,derived from neural crest *** paraganglioma is a type of head and neck paraganglioma involving the middle ear *** transcanal approach is currently in vogue for the excision of tympanic paragangliomas that is limited to middle ear *** present a series of 3 cases who underwent endoscopic excision of tympanic paraganglioma.

关键词： Tympanic paraganglioma Glomus tympanicum endoscopic excision

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Solidification of Cylindrical Aluminum Ingots With MHD-Stirring

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Journal of Iron and Steel Research International 2012年第S1期19卷 377-380页

作者： S.Yu.Khripchenko v.M.Dolgikh S.A.Denisov I.v.Kolesnichenko L.v.Nikulin v.J.Zayakin Institute of Continuous Media Mechanics UB RAS PermRussia Perm State National Research Polytechnical University PermRussia

The paper presents the results of experimental studies of the structure of cylindrical ingots of aluminum alloys, solidified at different modes of MHD-stirring generated by the traveling and rotating magnetic fields.

关键词： MHD-stirring solidification

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云南拉市海流域景观格局对地表水质的影响及尺度识别

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生态学杂志 2024年第6期43卷 1789-1798页

作者：张洪森角媛梅张华赵连勋陶妍徐秋娥张兆年云南师范大学地理学部昆明650500 自然资源部高原山地地质灾害预报预警与生态保护修复重点实验室/云南省地质环境监测院昆明650216 丽江拉市海高原湿地省级自然保护区管护局云南丽江674100

识别景观格局对地表水质的影响及其特征尺度是水环境研究领域的热点和难点。本文以滇西北拉市海流域为研究区,以50个水样点为中心,按照50 m的间距,计算其50~250 m的5个缓冲区的景观类型组成和10种景观格局指数,并与水体总磷、总氮进行... 详细信息

识别景观格局对地表水质的影响及其特征尺度是水环境研究领域的热点和难点。本文以滇西北拉市海流域为研究区,以50个水样点为中心,按照50 m的间距,计算其50~250 m的5个缓冲区的景观类型组成和10种景观格局指数,并与水体总磷、总氮进行相关性分析,识别景观格局对地表水质影响的特征尺度。结果表明:流域尺度景观格局具有山区-坝区显著分异特征,水样点缓冲区尺度景观格局指数在100 m缓冲区时出现明显变化;总磷和总氮平均浓度分别为0.12 mg·L^(-1)和1.61 mg·L^(-1),具有自上游向下游不断升高的趋势,样点间的污染程度空间差异明显;邻近水体的草地的地表水总磷浓度较高,山区林地的地表水总氮浓度较高;水样点缓冲区100 m时其景观格局与地表水质参数相关性最高,其中总磷浓度与斑块密度、边缘密度、景观形状指数、景观分裂指数和香农多样性指数呈显著正相关。因此,应重点关注坝区草地和拉市海周边100 m内的景观格局,以改善地表水质。

关键词：拉市海流域景观格局特征尺度水质高原湖泊

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Multiple stacking of InGaAs/GaAs(731) nanostructures

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Nano-Micro Letters 2009年第1期1卷 1-3页

作者： Y.Z.Xie v.P.Kunets Z.M.Wang v.Dorogan Y.I.Mazur J.Wu G.J.Salamo Institute of Nanoscale Science and engineering University of Arkansas

We studied the multilayering effects of InGaAs quantum dots(QDs) on GaAs(731), a surface lying inside of the stereographic triangle. The surfaces after stacking 16 InGaAs layers were characterized with highly non-uniformity of QD spatial distribution. The bunched step regions driven by strain accumulation are decorated by QDs, therefore GaAs(731) becomes a good candidate substrate for the growth of QD clusters. The unique optical properties of the QD clusters are revealed by photoluminescence measurements. By adjusting the coverage of InGaAs, a bamboo-like nanostructured surface was observed and the quantum dots aligned up in clusters to separate the "bamboo" into sections.

关键词： Quantum dots MBe High index surfaces Nanostructures Atomic force microscopy

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Cosmology with an effective Λ-Term in Lyra Manifold

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Chinese Physics Letters 2013年第11期30卷 215-219页

作者： v.K.Shchigolev Department of Theoretical Physics Ulyanovsk State UniversityUlyanovsk 432000Russia

A cosmological model in Lyra's geometry is studied under the assumption that an effective cosmological term appears in the field equations as the result of interaction between the displacement vector field and an auxiliaryΛ*** exact solutions to the model equations are obtained and preliminarily studied for the simplest cases in order to illustrate how such a model works.

关键词： equations exact auxiliary

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Utilizing natural cryogenic resources to improve the stability of natural-technical systems in the permafrost zone

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Research in Cold and Arid Regions 2017年第4期9卷 339-342页

作者： Rudolf v. Zhang Melnikov Permafrost Institute SB RAS Yakutsk 677010 Russia

Siberia and the Russian Far east contain about 75% of the country's hydrocarbon and mineral resources. These regions pose many engineering and environmental problems for economic development due to the cold climate and difficult geologic conditions, including the occurrence of permafrost. One of the major challenges in permafrost areas is to maintain the stability of both individual structures and large-scale engineering projects. The use of natural cryogenic resources of the earth is proposed here as one possible solution.

关键词： permafrost cryopeg cryogenic resource natural-technical system engineering foundation

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POLARIZATION IN B DeCAYS

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Chinese Physics C 2016年第10期40卷 759-762页

作者： A. v. Gritsan Johns Hopkins University

We review the notation used in polarization measurements in particle production and decay, with a particular emphasis on the B decays and the CP-violating observables in polarization measurements. We look at several examples of vector-vector and vector-tensor B meson decays, while more details about the theory and experimental results in B decays can be found in a separate mini-review [1] in this Review.

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