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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

抑制S100A4表达在奥马珠单抗对Ige诱导肥大细胞活化中的作用

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中国临床药理学杂志 2024年第17期40卷 2513-2517页

作者：杨蕾李燕燕樊长娥蔡慧娇甄华呼和浩特市第一医院药剂科内蒙古自治区呼和浩特010030 呼和浩特市第一医院变态(过敏)反应科内蒙古自治区呼和浩特010030

目的探讨抑制S100A4表达增强奥马珠单抗(OmAb)对免疫球蛋白e(Ige)预结合肥大细胞的解离作用。方法将LAD2细胞随机分为正常组、Ige组(Ige诱导)、奥马珠单抗低剂量组(0.5 mg·mL^(-1)OmAb)、奥马珠单抗中剂量组(1.0 mg·mL^(-1)OmAb)、奥... 详细信息

目的探讨抑制S100A4表达增强奥马珠单抗(OmAb)对免疫球蛋白e(Ige)预结合肥大细胞的解离作用。方法将LAD2细胞随机分为正常组、Ige组(Ige诱导)、奥马珠单抗低剂量组(0.5 mg·mL^(-1)OmAb)、奥马珠单抗中剂量组(1.0 mg·mL^(-1)OmAb)、奥马珠单抗高剂量组(2.0 mg·mL^(-1)OmAb)、高剂量+si-S100A4组(转染si-S100A4+2.0 mg·mL^(-1)OmAb)。用流式细胞术检测细胞表面Ige水平,用β-氨基己糖苷酶释放测定法测量脱颗粒,用酶联免疫吸附试验(eLISA)法检测各组细胞组胺、白三烯C4水平,用蛋白质印迹法检测相关蛋白的表达水平。结果正常组、Ige组、奥马珠单抗高剂量组、高剂量+si-S100A4组处理6 h后细胞表面Ige水平分别为(4.13±0.52)%、(100.00±6.20)%、(60.12±3.41)%和(54.04±5.60)%,β-氨基己糖苷酶释放率水平分别为(12.59±1.35)%、(69.27±6.43)%、(45.39±2.14)%和(37.80±2.77)%,组胺水平分别为(2.43±0.16)、(8.57±0.41)、(4.91±0.24)和(3.01±0.23)ng·mL^(-1),白三烯C4水平分别为(198.85±18.91)、(423.56±1.25)、(273.68±17.11)和(242.79±12.44)pg·mL^(-1),磷酸化-细胞外信号调节激酶(p-eRK)蛋白相对表达水平分别为0.31±0.04、0.91±0.12、0.55±0.04和0.35±0.02;Ige组的上述指标分别与正常组比较,奥马珠单抗高剂量组的上述指标分别与Ige组比较,高剂量+si-S100A4组的上述指标分别与奥马珠单抗高剂量组比较,在统计学上差异均有统计学意义(均Pe的解离作用,进一步阻断过敏介质的释放。

关键词：奥马珠单抗肥大细胞 S100钙结合蛋白A4 过敏反应过敏介质

Analyzing dynamic curve widening on forest roads

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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

Characteristics of X/γ-ray radiations by intense laser interactions with high-Z solids: The role of bremsstrahlung and radiation reactions

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Matter and Radiation at extremes 2018年第6期3卷 293-299页

作者： D.Wu W.yu y.T.Zhao S.Fritzsche X.T.He State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics201800 ShanghaiChina College of Science Xi'an Jiaotong UniversityXi'an 710049China Helmholtz Institute Jena D-07743 JenaGermany Theoretisch-Physikalisches Institut Friedrich-Schiller-University JenaD-07743 JenaGermany Key Laboratory of HeDP of the Ministry of education CAPTState Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing100871China

In this work, characteristics of X/γ-ray radiations by intense laser interactions with high-Z solids are investigated by means of a newlydeveloped particle-in-cell (PIC) simulation code. The PIC code takes advantage of the recently developed ionization and collision dynamicsmodels, which make it possible to model different types of materials based on their intrinsic atomic properties. Within the simulations, bothbremsstrahlung and nonlinear Compton scatterings have been included. Different target materials and laser intensities are considered forstudying the parameter-dependent features of X/γ-ray radiations. The relative strength and angular distributions of X/γ ray productions frombremsstrahlung and nonlinear Compton scatterings are compared to each other. The threshold under which the nonlinear Compton scatteringsbecome dominant over bremsstrahlung is also outlined.

关键词： Particle-in-cell simulations Bremsstrahlung Nonlinear Compton scattering Laser-solid interactions

effects of mountain pine beetle-killed forests on source water contributions to streamflow in headwater streams of the Colorado Rocky Mountains

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Frontiers of earth Science 2017年第3期11卷 496-504页

作者： Christine e. WeHNeR John D. STeDNICK Watershed Science Program College of Natural Resources Colorado State University Fort Collins CO 80523-1472 USA

Natural or human-influenced disturbances are important to the health and diversity of forests, which in turn, are important to the water quantity and quality exported from a catchment. However, human-induced disturbances （prescribed fire and harvesting） have been decreasing, and natural disturbances （fires and insects） have been increasing in frequency and severity. One such natural disturbance is the mountain pine beetle （MPB）, （Denclroctonus ponderosae） an endemic species. A recent epidemic resulted in the mortality of millions of hectares of lodgepole pine （Pinus contorta） forests in Colorado, USA. Beetle-induced tree mortality brings about changes to the hydrologic cycle, including decreased transpiration and interception with the loss of canopy cover. This study examined the effect of the mountain pine beetle kill on source water contributions to streamflow in snowmelt- dominated headwater catchments using stable isotopes （2H and ~80） as tracers. Study catchments with varying level of beetle-killed forest area （6% to 97%） were sampled for groundwater, surface water, and precipitation. Streams were sampled to assess whether beetle-killed forests have altered source water contributions to streamflow. Ground- water contributions increased with increasing beetle-killed forest area （p = 0.008）. Both rain and snow contributions were negatively correlated with beetle-killed forest area （p = 0.035 and p = 0.011, respectively）. As the beetle-killed forest area increases, so does fractional groundwater contribution to streamflow.

关键词： mountain pine beetle isotope tracers stream-flow generation headwaters

不同深蓄储水灌溉量对冬小麦磷素利用和磷素下渗流失风险的影响

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植物营养与肥料学报 2024年第3期30卷 493-504页

作者：庞耀悦胡笑涛王芳查晴范晓懂王文娥西北农林科技大学/旱区农业水土工程教育部重点实验室陕西杨凌712100

[目的]汛前储水灌溉是陕西关中地区雨洪资源高效利用的重要方式。研究不同深蓄储水灌溉量对农田土壤磷素利用、累积与流失状况的影响,以实现农田的“高”磷吸收和“低”磷淋溶。[方法]在陕西宝鸡峡灌区进行小麦田间试验,供试小麦品种为... 详细信息

[目的]汛前储水灌溉是陕西关中地区雨洪资源高效利用的重要方式。研究不同深蓄储水灌溉量对农田土壤磷素利用、累积与流失状况的影响,以实现农田的“高”磷吸收和“低”磷淋溶。[方法]在陕西宝鸡峡灌区进行小麦田间试验,供试小麦品种为‘小偃22’。设置储水灌溉量分别为0、80、120、140、160和180 cm,分别记为CK、D80、D120、D140、D160、D180,共6个处理。在小麦拔节期、开花期和成熟期,测定冬小麦植株各营养器官生物量、磷素含量及农田0—200 cm土层土壤速效磷含量,计算冬小麦吸磷量、磷肥利用效率和磷素盈亏。[结果]与CK处理相比,D80、D120、D140、D160、D180处理冬小麦产量分别提高了8.85%、24.71%、30.99%、17.91%、9.90%,成熟期籽粒磷素累积量分别提高了37.55%、46.34%、38.09%、28.23%、22.11%,小麦植株磷素吸收效率分别增加10.10%、12.47%、10.25%、7.59%、5.95%,有效磷表观盈余量分别降低了13.82%、17.05%、14.02%、10.39%、8.13%。随着储水灌溉量的增加,成熟期小麦植株磷素累积量呈先增加后降低的趋势,以D120处理磷素累积量最高,显著高于D160和D180处理,因此其磷素表观盈余量最低(78.83 kg/hm^(2)),显著低于D160、D180处理。D120处理相较D160和D180有助于小麦花前磷素转运和花后磷素累积;D80处理相较D120处理小麦花前磷素转运有所降低,但在花后磷素累积上表现出补偿作用;D140处理虽然降低了花后的磷素累积,但通过提高花前磷素转运实现了平衡。值得注意的是,D80、D120和D140处理之间的成熟期植株磷素累积量与籽粒磷素累积量差异不显著。另外,由于土壤中20-100 cm土层速效磷含量远低于该地磷素淋溶的环境阈值(39.9 mg/kg),尽管存在高水平的磷盈余,在适宜储水灌溉量下也不会引发磷淋失。然而,当储水深度大于160 cm时,对深层土壤中速效磷产生了明显的影响,导致土壤磷素发生淋失。[结论]在西北地区,适宜的储水灌溉量为80~140 cm,既可以提高小麦磷素吸收,又可以控制土壤中速效磷含量处于适宜范围,降低土壤磷素盈余,进而获得较低的土壤磷素环境风险。

关键词：储水灌溉深度磷素利用效率磷素淋失磷素盈余

Inhibition of hepatitis C virus replication by single-stranded RNA structural mimics

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World Journal of Gastroenterology 2010年第17期16卷 2100-2108页

作者： Robert Smolic Martina Smolic John H Andorfer Catherine H Wu Robert M Smith George y Wu Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health Center263 Farmington Ave.FarmingtonCT 06030-1845United States

AIM: To examine the effect of hepatitis C virus (HCV) structural mimics of regulatory regions of the genome on HCV ***: HCV RNA structural mimics were constructed and tested in a HCV genotype 1b aBB7 replicon,and a Japanese fulminant hepatitis-1 (JFH-1) HCV genotype 2a infection *** sequences were computer-predicted to adopt stem-loop structures identical to the corresponding elements in full-length viral ***7.5 cells bearing the BB7 replicon or infected with JFH-1 virus were transfected with expression vectors generating HCV mimics and *** HCV RNA and protein levels were quantified by real-time polymerase chain reaction and Western blotting,*** evaluate possible antisense effects,complementary RNAs spanning a mimic were ***: In the BB7 genotype 1b replicon system,mimics of the polymerase (NS-5B),X and BA regions inhibited replication by more than 90%,50%,and 60%,*** the JFH-1 genotype 2 infection system,mimics that were only 74% and 46% identical in sequence relative to the corresponding region in JFH-1 inhibited HCV replication by 91.5% and 91.2%,respectively,as effectively as a mimic with complete identity to HCV genotype *** inhibitory effects were confirmed by NS3 protein *** RNA molecules spanning the 74% identical mimic had no significant ***: HCV RNA structural mimics can inhibit HCV RNA replication in replicon and infectious HCV systems and do so independent of close sequence identity with the target.

关键词： Hepatitis C virus Japanese fulminant hepatitis virus Complementarity RNA sequence Hybridization

An unsupervised learning approach to study synchroneity of past events in the South China Sea

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Frontiers of earth Science 2019年第3期13卷 628-640页

作者： Kevin C. Tse Hon-Chim Chiu Man-yin Tsang yiliang Li edmund y. Lam Department of earth Sciences The University of Hong KongPokfulamHong KongChina Department of Geography and Centre for Geo-computation Studies Hong Kong Baptist UniversityKowloon TongHong KongChina Department of earth Sciences University of TorontoCanada Department of electrical and electronic engineering The University of Hong KongPokfulamHong KongChina

Unsupervised machine learning methods were applied on multivariate geophysical and geochemical datasets of ocean floor sediment cores collected from the South China Sea. The well-preserved and continuous core samples comprising high resolution Cenozoic sediment records enable scientists to carry out paleoenvironment studies in detail. Bayesian age-depth chronological models constructed from biostratigraphic control points for the drilling sites are applied on cluster boundaries generated from two popular unsupervised learning methods: K-means and random forest. The unsupervised learning methods experimented have produced compact and unambiguous clusters from the datasets, indicating that previously unknown data patterns can be revealed when all variables from the datasets are taken into account simultaneously. A study of synchroneity of past events represented by the cluster boundaries across geographically separated ocean drilling sites is achieved through converting the fixed depths of cluster boundaries into chronological ranges represented by Gaussian density plots which are then compared with known past events in the region. A Gaussian density peak at around 7.2 Ma has been identified from results of all three sites and it is suggested to coincide with the initiation of the east Asian monsoon. Contrary to traditional statistical approach, a priori assumptions are not required for unsupervised learning, and the clustering results serve as a novel data-driven proxy for studying the complex and dynamic processes of the paleoenvironment surrounding the ocean sediment. This work serves as a pioneering approach to extract valuable information of regional events and opens up a systematic and objective way to study the vast global ocean sediment datasets.

关键词： machine learning ocean sediments unsupervised classification

Correlation between the structural, morphological, optical, and electrical properties of In_2O_3 thin films obtained by an ultrasonic spray CVD process

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Journal of Semiconductors 2015年第8期36卷 9-14页

作者： A.Bouhdjer A.Attaf H.Saidi H.Bendjedidi y.Benkhetta I.Bouhaf Laboratory of Semiconductors Materials University of Med Kheider

Indium oxide （In2O3） thin films are successfully times by an ultrasonic spray technique using Indium chloride deposited on glass substrate at different deposition as the precursor solution; the physical properties of these films are characterized by XRD, SeM, and UV-visible. XRD analysis showed that the films are polycrys- talline in nature having a cubic crystal structure and symmetry space group Ia3 with a preferred grain orientation along the （222） plane when the deposition time changes from 4 to 10 min, but when the deposition time equals 13 min we found that the majority of grains preferred the （400） plane. The surface morphology of the In2O3 thin films revealed that the shape of grains changes with the change of the preferential growth orientation. The trans- mittance improvement of In2O3 films was closely related to the good crystalline quality of the films. The optical gap energy is found to increase from 3.46 to 3.79 eV with the increasing of deposition time from 4 to 13 min. The film thickness was varied between 395 and 725 nm. The film grown at 13 min is found to exhibit low resistivity （10-2 Ω.cm）, and relatively high transmittance （- 93%）.

关键词： indium oxide deposition time ultrasonic spray optical and electrical properties