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MAP1家族:探索未知功能的新视角
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作者 王晴 刘梅 董张及 《生理学报》 北大核心 2025年第5期876-892,共17页
微管作为细胞骨架的重要组成部分,在细胞分裂、细胞内转运以及维持细胞形态等诸多细胞过程中发挥着至关重要的作用。MAP1家族是一类重要的微管相关蛋白,包含MAP1A、MAP1B和MAP1S三个成员。这些蛋白质广泛参与细胞骨架的动态调节,在中枢... 微管作为细胞骨架的重要组成部分,在细胞分裂、细胞内转运以及维持细胞形态等诸多细胞过程中发挥着至关重要的作用。MAP1家族是一类重要的微管相关蛋白,包含MAP1A、MAP1B和MAP1S三个成员。这些蛋白质广泛参与细胞骨架的动态调节,在中枢神经系统的发育和功能中起着关键作用,尤其在神经元的发育与功能方面表现突出。本文对MAP1家族的研究进展进行了综述,主要聚焦MAP1家族成员的结构与功能,并重点关注它们在神经元发育再生、调控机制以及神经退行性疾病中的作用。 展开更多
关键词 微管相关蛋白 map1 map1A map1B map1S 神经退行性疾病
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Processing map for oxide dispersion strengthening Cu alloys based on experimental results and machine learning modelling
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作者 Le Zong Lingxin Li +8 位作者 Lantian Zhang Xuecheng Jin Yong Zhang Wenfeng Yang Pengfei Liu Bin Gan Liujie Xu Yuanshen Qi Wenwen Sun 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期292-305,共14页
Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening pa... Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening particles also deteriorates the processability and it is of great importance to establish accurate processing maps to guide the thermomechanical processes to enhance the formability.In this study,we performed particle swarm optimization-based back propagation artificial neural network model to predict the high temperature flow behavior of 0.25wt%Al2O3 particle-reinforced Cu alloys,and compared the accuracy with that of derived by Arrhenius-type constitutive model and back propagation artificial neural network model.To train these models,we obtained the raw data by fabricating ODS Cu alloys using the internal oxidation and reduction method,and conducting systematic hot compression tests between 400 and800℃with strain rates of 10^(-2)-10 S^(-1).At last,processing maps for ODS Cu alloys were proposed by combining processing parameters,mechanical behavior,microstructure characterization,and the modeling results achieved a coefficient of determination higher than>99%. 展开更多
关键词 oxide dispersion strengthened Cu alloys constitutive model machine learning hot deformation processing maps
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The Map Museum of Zhengzhou University
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作者 GAO Jun LI Hongwei +4 位作者 TIAN Zhihui SUN Qun SHAO Shixin LI Haolin LI Jian 《Journal of Geodesy and Geoinformation Science》 2025年第1期100-101,共2页
On April 28,2023,the Map Museum of Zhengzhou University was officially opened in the historical Central Plains of China.The museum was founded by Mr.GAO Jun,Distinguished Academician of the Chinese Academy of Sciences... On April 28,2023,the Map Museum of Zhengzhou University was officially opened in the historical Central Plains of China.The museum was founded by Mr.GAO Jun,Distinguished Academician of the Chinese Academy of Sciences and Dean of the School of Geo-Science and Technology at Zhengzhou University.The establishment of the Map Museum reflects the vigorous development of Chinese cartography and its advancement toward world-class level.Additionally,it marks a significant milestone in promoting Chinese map culture. 展开更多
关键词 map museum promoting chinese map culture Zhengzhou University Chinese cartography world class level Chinese map culture
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Single Qubit Quantum Logistic-Sine XYZ-Rotation Maps:An Ultra-Wide Range Dynamics for Image Encryption
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作者 De Rosal Ignatius Moses Setiadi T.Sutojo +4 位作者 Supriadi Rustad Muhamad Akrom Sudipta Kr Ghosal Minh T.Nguyen Arnold Adimabua Ojugo 《Computers, Materials & Continua》 2025年第5期2161-2188,共28页
Data security has become a growing priority due to the increasing frequency of cyber-attacks,necessitating the development of more advanced encryption algorithms.This paper introduces Single Qubit Quantum Logistic-Sin... Data security has become a growing priority due to the increasing frequency of cyber-attacks,necessitating the development of more advanced encryption algorithms.This paper introduces Single Qubit Quantum Logistic-Sine XYZ-Rotation Maps(SQQLSR),a quantum-based chaos map designed to generate one-dimensional chaotic sequences with an ultra-wide parameter range.The proposed model leverages quantum superposition using Hadamard gates and quantum rotations along the X,Y,and Z axes to enhance randomness.Extensive numerical experiments validate the effectiveness of SQQLSR.The proposed method achieves a maximum Lyapunov exponent(LE)of≈55.265,surpassing traditional chaotic maps in unpredictability.The bifurcation analysis confirms a uniform chaotic distribution,eliminating periodic windows and ensuring higher randomness.The system also generates an expanded key space exceeding 10^(40),enhancing security against brute-force attacks.Additionally,SQQLSR is applied to image encryption using a simple three-layer encryption scheme combining permutation and substitution techniques.This approach is intentionally designed to highlight the impact of SQQLSR-generated chaotic sequences rather than relying on a complex encryption algorithm.Theencryption method achieves an average entropy of 7.9994,NPCR above 99.6%,and UACI within 32.8%–33.8%,confirming its strong randomness and sensitivity to minor modifications.The robustness tests against noise,cropping,and JPEG compression demonstrate its resistance to statistical and differential attacks.Additionally,the decryption process ensures perfect image reconstruction with an infinite PSNR value,proving the algorithm’s reliability.These results highlight SQQLSR’s potential as a lightweight yet highly secure encryption mechanism suitable for quantum cryptography and secure communications. 展开更多
关键词 Single qubit quantumchaotic quantumchaotic map quantumimage encryption quantumlogistic map quantum sine map
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Preliminary hydrogeological implications using structural analysis and cave mapping:a case study of the Pachnes Thrust,Central Lefka Ori,Crete
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作者 Daniel Moraetis Aris Leontaritis +12 位作者 Andreas Scharf Charalampos Fassoulas Stylianos Zacharias Arnauld Malard Frank Mattern Asma Alnaqbi Hamdan Hamdan Markos Digenis Christos Pennos Kostas Adamopoulos Xuan Yu Nikolaos Nikolaidis Kosmas Pavlopoulos 《Episodes》 2025年第4期385-401,共17页
This multidisciplinary study integrates structural and cave mapping,3D geological modeling,and Geographical Information System(GIS)analysis to provide constraints of the hydrogeological model for the central Lefka Ori... This multidisciplinary study integrates structural and cave mapping,3D geological modeling,and Geographical Information System(GIS)analysis to provide constraints of the hydrogeological model for the central Lefka Ori Massif.Through 44 km of linear mapping,we discovered the new mid-Miocene Pachnes Thrust(PT)which plays a key role in the central Lefka Ori Massif structural framework. 展开更多
关键词 hydrogeological model structural analysis hydrogeological implications linear mappingwe structural cave mapping d geological modelingand D geological modeling cave mapping geographical information system gis analysis
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基于T_(2)mapping及超短回波时间技术定量探究早期膝骨关节炎的发病机制 被引量:2
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作者 牛飞格 孟祥虹 +1 位作者 孙曼 王植 《临床放射学杂志》 北大核心 2025年第2期350-356,共7页
目的基于浅表软骨的T_(2)mapping和骨软骨交界区(OCJ)的超短回波时间(UTE)T_(2)^(*)mapping探究膝骨关节炎(KOA)早期浅表软骨和骨软骨交界区的病变顺序。方法对纳入的30个健康膝和30个早期骨性关节炎膝进行常规和定量MRI扫描,主要扫描... 目的基于浅表软骨的T_(2)mapping和骨软骨交界区(OCJ)的超短回波时间(UTE)T_(2)^(*)mapping探究膝骨关节炎(KOA)早期浅表软骨和骨软骨交界区的病变顺序。方法对纳入的30个健康膝和30个早期骨性关节炎膝进行常规和定量MRI扫描,主要扫描序列包括三维水激发序列(3D WATS)、T_(2)mapping和UTE T_(2)^(*)mapping。将每个膝关节都分为股骨内侧髁、股骨外侧髁、胫骨内侧髁、胫骨外侧髁、髌骨和滑车区6个区域并测量每个区域的浅层软骨T_(2)值和OCJ T_(2)^(*)值。用独立样本t检验比较健康组和早期KOA组间的浅层软骨T_(2)值及OCJ T_(2)^(*)值。用Spearman相关性检验评估浅层软骨T_(2)值与OCJ T_(2)^(*)值间的相关性。结果早期KOA组的浅层软骨T_(2)值在股骨内侧髁(P<0.001)、胫骨内侧平台(P<0.001)、髌骨(P<0.001)和股骨滑车区(P=0.01)相对于健康组显著升高。早期KOA组OCJ T_(2)^(*)值在股骨内侧髁(P<0.001)、胫骨内侧平台(P<0.001)、胫骨外侧平台(P<0.001)、髌骨(P=0.001)和滑车区(P<0.001)均显著升高。浅层软骨T_(2)值和骨软骨交界区T_(2)^(*)值间存在正相关关系(r=0.37,P<0.001)。结论浅表软骨的T_(2)mapping和骨软骨交界区的UTE T_(2)^(*)mapping成像都可定量且无创识别早期KOA。在KOA早期,浅表软骨和OCJ都出现了生化改变。 展开更多
关键词 骨性关节炎 关节软骨骨软骨交界区 T_(2)mapping T_(2)^(*)mapping
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Leveraging ROTI map derived from Indonesian GNSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia 被引量:1
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作者 Prayitno Abadi Ihsan N.Muafiry +8 位作者 Teguh N.Pratama Angga Y.Putra Suraina Gatot H.Pramono Sidik T.Wibowo Febrylian F.Chabibi Umar A.Ahmad Wildan P.Tresna Asnawi 《Earth and Planetary Physics》 EI CAS 2025年第1期101-116,共16页
This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signa... This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning accuracy.Managed by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude regions.Ina-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast Asia.We provide a practical tool for EPB research,by sharing two-dimensional rate of Total Electron Content(TEC)change index(ROTI)derived from this network.We generate ROTI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific research.Two preliminary findings from the ROTI maps of Ina-CORS are noteworthy.First,the Ina-CORS ROTI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther eastward.Second,we demonstrate that combined ROTI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East Asia.We have demonstrated the combined ROTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,2024.We observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities post-midnight.By sharing ROTI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionospheric research. 展开更多
关键词 Equatorial Plasma Bubble(EPB) GNSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of TEC change index(ROTI)map
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MR T_(1)-mapping结合动脉自旋标记技术在评估儿童慢性肾脏病肾纤维化和灌注中的应用 被引量:1
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作者 赵佳佳 胡俊 +2 位作者 尹传高 顾东浩 朱晓冬 《临床放射学杂志》 北大核心 2025年第3期513-517,共5页
目的初步研究MR纵向弛豫时间定量成像(T 1-mapping)和动脉自旋标记技术(ASL)在诊断儿童慢性肾脏病(CKD)中的应用价值。方法纳入CKD患儿32例(包括肾脏未萎缩19例,萎缩13例),同期招募健康志愿者30名作对照组,行T 1-mapping和ASL序列扫描,... 目的初步研究MR纵向弛豫时间定量成像(T 1-mapping)和动脉自旋标记技术(ASL)在诊断儿童慢性肾脏病(CKD)中的应用价值。方法纳入CKD患儿32例(包括肾脏未萎缩19例,萎缩13例),同期招募健康志愿者30名作对照组,行T 1-mapping和ASL序列扫描,分别获得肾皮质T 1值和肾皮质血流量(RBF)。比较对照组和CKD组患儿肾皮质T 1值和RBF值的差异,并分析CKD组肾皮质T 1值和RBF值与估算肾小球滤过率(eGFR)、血肌酐(Scr)、血胱抑素C(Cys-C)的相关性。结果CKD组较对照组肾皮质T 1值明显升高、RBF值明显减低(P<0.05);CKD组中,肾脏未萎缩患儿肾皮质T 1值与eGRF、Scr、Cys-C呈高、中度相关(r=-0.832、0.777、0.698,P<0.05),肾脏萎缩患儿肾皮质T 1值与eGRF、Scr呈高度相关(r=0.726、-0.743,P<0.05);CKD组肾皮质RBF与eGRF、Cys-C、Scr呈中度相关(r=0.699、-0.619、-0.554,P<0.05)。结论MR T_(1)-mapping和ASL定量反映肾脏微观病理变化及血流灌注情况,具有预测肾脏慢性病理损伤的潜在价值,有望在肾脏发生不可逆损伤前早期、无创地提供肾脏功能信息。 展开更多
关键词 慢性肾脏病 儿童 T_(1)-mapping 动脉自旋标记 磁共振功能成像
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副结核分支杆菌MAP0862-2191c串联蛋白的原核表达及反应原性检测
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作者 郝彦儒 郭号 +3 位作者 谢梦圆 陈坚 杨文洁 徐晓静 《动物医学进展》 北大核心 2025年第4期28-34,共7页
副结核分支杆菌(MAP)由于其胞内寄生的特性,难以在早期发现,待发现后往往已经不再具备治疗价值,因此寻找并制备出能同时在早晚期都有显著标识作用的抗原蛋白,有利于更好地诊断牛副结核病。通过生物信息学软件对MAP的MAP0862和MAP2191c... 副结核分支杆菌(MAP)由于其胞内寄生的特性,难以在早期发现,待发现后往往已经不再具备治疗价值,因此寻找并制备出能同时在早晚期都有显著标识作用的抗原蛋白,有利于更好地诊断牛副结核病。通过生物信息学软件对MAP的MAP0862和MAP2191c两种蛋白进行一级、二级及三级结构上的理化性质、抗原性分析及相对位置建模预测,判断串联蛋白重组表达的可行性;使用柔性肽短链序列(G4S)2连接两段序列构建了重组表达载体pET30a-MAP6291c,将其导入至BL21(DE3)原核表达载体中进行诱导表达,并进行Western blot分析。结果显示,预测MAP0862-2191c串联蛋白为一个有多个抗原表位的亲水性的蛋白,两种蛋白在三级结构上无相互影响,因此可以进行原核表达;构建合成的融合基因双酶切结果与预期结果相符;经SDS-PCGE凝胶电泳检测成功表达串联蛋白,大小约68.5 ku,与预期蛋白大小相符;分别选择鼠源抗His抗体及MAP阳性牛血清作为一抗进行Western blot验证,均显示MAP0862-2191c重组蛋白有单一的特异性条带,位置及大小与预期结果一致,证明了该串联蛋白制备的正确性,并且具有良好的反应原性,能够作为牛副结核病的诊断蛋白,为后续建立牛副结核病的诊断方法奠定了良好基础。 展开更多
关键词 副结核分支杆菌 map0862 map2191c 蛋白预测 串联表达
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梨形环棱螺Map2k1基因的分子特征和功能分析
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作者 金鑫 缪煜琳 +3 位作者 王萍 顾洋 吕伙红 汪桂玲 《上海海洋大学学报》 北大核心 2025年第6期1203-1213,共11页
为了探究Map2k1基因在梨形环棱螺性腺发育及性别分化中的作用,采用基因克隆、实时荧光定量、原位杂交以及RNA干扰技术来研究Map2k1在梨形环棱螺中的表达和功能。结果显示,Map2k1 cDNA ORF区全长1191 bp,编码396个氨基酸,MAP2K1蛋白中含... 为了探究Map2k1基因在梨形环棱螺性腺发育及性别分化中的作用,采用基因克隆、实时荧光定量、原位杂交以及RNA干扰技术来研究Map2k1在梨形环棱螺中的表达和功能。结果显示,Map2k1 cDNA ORF区全长1191 bp,编码396个氨基酸,MAP2K1蛋白中含有S_TKc结构域,其氨基酸序列与软体动物同源性较高。Map2k1在雄性和雌性多种组织中均有表达,尤其是在雌性性腺中的表达量最高,且雌雄性腺的表达水平存在极显著差异(P<0.01)。原位杂交的结果表明,在雌性梨形环棱螺卵母细胞和卵巢囊泡中,Map2k1存在明显的杂交信号。RNA干扰的结果显示,在雌性梨形环棱螺中,Map2k1的干扰链G1在注射后12 h达到最高干扰率,为73.1%,并导致其他性别相关基因β-catenin、Cyp17a1和Sox9表达量显著降低。研究表明,Map2k1可能参与了雌性梨形环棱螺性腺发育和性别分化过程。本研究可为梨形环棱螺性腺发育和单性化育种研究提供理论参考。 展开更多
关键词 梨形环棱螺 map2k1基因 性腺发育 RNA干扰
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3.0T磁共振T2 mapping序列联合血清新饱食分子蛋白1水平检测在老年膝关节早期骨关节炎诊断中的应用价值
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作者 唐利 巩玉荣 +2 位作者 曾立叶 高艳芳 邓成哲 《实用医学杂志》 北大核心 2025年第8期1238-1242,共5页
目的探讨3.0 T磁共振(MRI)T2 mapping序列联合血清新饱食分子蛋白1(nesfatin-1)水平对老年膝关节早期骨关节炎(OA)的诊断价值。方法选取2023年5月至2024年5月医院收治的膝关节OA的97例老年患者(OA组)和52例同期老年体检者(对照组),根据... 目的探讨3.0 T磁共振(MRI)T2 mapping序列联合血清新饱食分子蛋白1(nesfatin-1)水平对老年膝关节早期骨关节炎(OA)的诊断价值。方法选取2023年5月至2024年5月医院收治的膝关节OA的97例老年患者(OA组)和52例同期老年体检者(对照组),根据X线结果将膝关节OA组分为早期组和非早期组,均接受3.0T MRI T2 mapping序列扫描检测膝关节软骨区域T2值,检测血清nesfatin-1水平,比较上述指标差异并采用ROC曲线分析其对老年膝关节早期OA的诊断价值。结果97例老年膝关节OA患者中,早期组35例,非早期组62例,OA组患者膝关节5个软骨区域的T2值及nesfatin-1血清均高于对照组(P<0.05),早期组均低于非早期组(P<0.05);膝关节软骨区域T2值和血清nesfatin-1水平单独诊断早期OA的AUC在0.774~0.871范围,联合诊断的AUC为0.939。结论3.0 T磁共振T2 mapping序列联合血清nesfatin-1水平检测对老年膝关节早期OA具有较高的诊断价值。 展开更多
关键词 膝关节早期骨关节炎 老年 磁共振 T2 mapping序列 新饱食分子蛋白1
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ON THE CONVERGENCE PROBLEMS OF ISHIKAWA AND MANN ITERATIVE PROCESSES WITH ERROR FOR Φ-PSEUDO CONTRACTIVE TYPE MAPPINGS 被引量:1
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作者 张石生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第1期3-14,共12页
The purpose of this paper is to introduce the concept of Φ_pseudo contractive type mapping and to study the convergence problem of Ishikawa and Mann iterative processes with error for this kind of mappings. The resul... The purpose of this paper is to introduce the concept of Φ_pseudo contractive type mapping and to study the convergence problem of Ishikawa and Mann iterative processes with error for this kind of mappings. The results presented in this paper improve and extend many authors'recent results. 展开更多
关键词 Φ-pseudo contractive type mapping accretive mapping pseudo_contractive mapping Φ_strongly accretive mapping Φ_hemi_contractive mapping Ishikawa iterative processes with error Mann iterative process with error
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基于ArcMap的森林资源调查地形图接图网制作
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作者 胡卫东 龙艳 《计算机应用文摘》 2025年第9期176-179,182,共5页
文章以广西森林资源调查1∶1万地形图接图网的制作过程为例,利用ArcMap 10.8的渔网工具、创建自定义地理(坐标)变换工具和投影工具,制作了基于CGCS2000坐标系的1∶1万地形图接图网,以及1954北京坐标系转CGCS2000坐标系和1980西安坐标系... 文章以广西森林资源调查1∶1万地形图接图网的制作过程为例,利用ArcMap 10.8的渔网工具、创建自定义地理(坐标)变换工具和投影工具,制作了基于CGCS2000坐标系的1∶1万地形图接图网,以及1954北京坐标系转CGCS2000坐标系和1980西安坐标系转CGCS2000坐标系的1∶1万地形图接图网,旨在通过接图网,在CGCS2000坐标系下,快速、准确、高效地完成不同坐标系下的1∶1万地形图栅格配准。 展开更多
关键词 森林资源调查 ARCmap 地形图 接图网 配准
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A Secure Audio Encryption Method Using Tent-Controlled Permutation and Logistic Map-Based Key Generation
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作者 Ibtisam A.Taqi Sarab M.Hameed 《Computers, Materials & Continua》 2025年第10期1653-1674,共22页
The exponential growth of audio data shared over the internet and communication channels has raised significant concerns about the security and privacy of transmitted information.Due to high processing requirements,tr... The exponential growth of audio data shared over the internet and communication channels has raised significant concerns about the security and privacy of transmitted information.Due to high processing requirements,traditional encryption algorithms demand considerable computational effort for real-time audio encryption.To address these challenges,this paper presents a permutation for secure audio encryption using a combination of Tent and 1D logistic maps.The audio data is first shuffled using Tent map for the random permutation.The high random secret key with a length equal to the size of the audio data is then generated using a 1D logistic map.Finally,the Exclusive OR(XOR)operation is applied between the generated key and the shuffled audio to yield the cipher audio.The experimental results prove that the proposed method surpassed the other techniques by encrypting two types of audio files,as mono and stereo audio files with large sizes up to 122 MB,different sample rates 22,050,44,100,48,000,and 96,000 for WAV and 44,100 sample rates for MP3 of size 11 MB.The results show high Mean Square Error(MSE),low Signal-to-Noise Ratio(SNR),spectral distortion,100%Number of Sample Change Rate(NSCR),high Percent Residual Deviation(PRD),low Correlation Coefficient(CC),large key space 2^(616),high sensitivity to a slight change in the secret key and that it can counter several attacks,namely brute force attack,statistical attack,differential attack,and noise attack. 展开更多
关键词 Wave protection 1D logistic map Tent map random permutation key generation
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磁共振T2-mapping成像技术在膝关节骨性关节炎诊断中应用的研究进展
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作者 陈思 《黑龙江医学》 2025年第16期2042-2044,2048,共4页
T2-mapping成像技术通过分析软骨的T2弛豫时间,定量评估软骨组织学结构,揭示软骨中水含量和胶原纤维排列的变化,适用于早期检测软骨损伤和监测疾病进展,对评估软骨健康状况至关重要。T2-mapping成像技术不仅对膝关节骨性关节炎(KOA)的... T2-mapping成像技术通过分析软骨的T2弛豫时间,定量评估软骨组织学结构,揭示软骨中水含量和胶原纤维排列的变化,适用于早期检测软骨损伤和监测疾病进展,对评估软骨健康状况至关重要。T2-mapping成像技术不仅对膝关节骨性关节炎(KOA)的早期诊断和进展监测具有重要价值,还能在软骨修复过程中监测和评估软骨的生化变化。随着成像技术和数据处理能力的进一步发展,T2-mapping成像有望提高诊断精度、优化治疗方案,为KOA的管理和治疗带来革新。文章综述了磁共振成像技术(MRI)中的T2-mapping成像技术在KOA诊断和评估中的应用。 展开更多
关键词 磁共振T2-mapping成像 膝关节 骨性关节炎
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IsoVISoR: Towards 3D Mesoscale Brain Mapping of Large Mammals at Isotropic Sub-micron Resolution
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作者 Chao-Yu Yang Yan Shen +9 位作者 Xiaoyang Qi Lufeng Ding Yanyang Xiao Qingyuan Zhu Hao Wang Cheng Xu Pak-Ming Lau Pengcheng Zhou Fang Xu Guo-Qiang Bi 《Neuroscience Bulletin》 2025年第2期344-348,共5页
Dear Editor,The mammalian brain exhibits cross-scale complexity in neuronal morphology and connectivity,the study of which demands high-resolution morphological reconstruction of individual neurons across the entire b... Dear Editor,The mammalian brain exhibits cross-scale complexity in neuronal morphology and connectivity,the study of which demands high-resolution morphological reconstruction of individual neurons across the entire brain[1-4].Current commonly used approaches for such mesoscale brain mapping include two main types of three-dimensional fluorescence microscopy:the block-face methods,and the lightsheet-based methods[5,6].In general,the high imaging speed and light efficiency of light-sheet microscopy make it a suitable tool for high-throughput volumetric imaging,especially when combined with tissue-clearing techniques.However,large brain samples pose major challenges to this approach. 展开更多
关键词 brain mapping three dimensional fluorescence microscopy mesoscale brain mapping lightsheet based methods block face methods high throughput volumetric imaging tissue clearing techniques
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Comparing disaggregation approaches DSMART and PPD in disaggregating soil series maps
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作者 Tahmid Huq EASHER Daniel SAURETTE +3 位作者 Brandon HEUNG Adam GILLESPIE Richard J.HECK Asim BISWAS 《Pedosphere》 2025年第2期387-404,共18页
Conventional soil maps(CSMs)often have multiple soil types within a single polygon,which hinders the ability of machine learning to accurately predict soils.Soil disaggregation approaches are commonly used to improve ... Conventional soil maps(CSMs)often have multiple soil types within a single polygon,which hinders the ability of machine learning to accurately predict soils.Soil disaggregation approaches are commonly used to improve the spatial and attribute precision of CSMs.The approach disaggregation and harmonization of soil map units through resampled classification trees(DSMART)is popular but computationally intensive,as it generates and assigns synthetic samples to soil series based on the areal coverage information of CSMs.Alternatively,the disaggregation approach pure polygon disaggregation(PPD)assigns soil series based solely on the proportions of soil series in pure polygons in CSMs.This study compared these two disaggregation approaches by applying them to a CSM of Middlesex County,Ontario,Canada.Four different sampling methods were used:two sampling designs,simple random sampling(SRS)and conditional Latin hypercube sampling(cLHS),with two sample sizes(83100 and 19420 samples per sampling plan),both based on an area-weighted approach.Two machine learning algorithms(MLAs),C5.0 decision tree(C5.0)and random forest(RF),were applied to the disaggregation approaches to compare the disaggregation accuracy.The accuracy assessment utilized a set of 500 validation points obtained from the Middlesex County soil survey report.The MLA C5.0(Kappa index=0.58–0.63)showed better performance than RF(Kappa index=0.53–0.54)based on the larger sample size,and PPD with C5.0 based on the larger sample size was the best-performing(Kappa index=0.63)approach.Based on the smaller sample size,both cLHS(Kappa index=0.41–0.48)and SRS(Kappa index=0.40–0.47)produced similar accuracy results.The disaggregation approach PPD exhibited lower processing capacity and time demands(1.62–5.93 h)while yielding maps with lower uncertainty as compared to DSMART(2.75–194.2 h).For CSMs predominantly composed of pure polygons,utilizing PPD for soil series disaggregation is a more efficient and rational choice.However,DSMART is the preferable approach for disaggregating soil series that lack pure polygon representations in the CSMs. 展开更多
关键词 conditioned Latin hypercube sampling conventional soil map machine learning algorithm processing capacity and time sample size simple random sampling soil map unit soil series disaggregation
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Mapmaker3.0和作图软件使用 被引量:9
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作者 王竹林 杨睿 +2 位作者 杨兴圣 刘曙东 胡甘 《实验室研究与探索》 CAS 北大核心 2012年第11期62-65,共4页
构建各种生物体的遗传连锁图谱成为分子遗传学和作物育种领域QTL定位的热点。Mapmaker3.0是当前普遍用于遗传连锁距离计算的软件。Mapmaker3.0的使用首先要准备标记数据文件,然后用Sequence命令输入欲分析的标记座位,接着键入Group命令... 构建各种生物体的遗传连锁图谱成为分子遗传学和作物育种领域QTL定位的热点。Mapmaker3.0是当前普遍用于遗传连锁距离计算的软件。Mapmaker3.0的使用首先要准备标记数据文件,然后用Sequence命令输入欲分析的标记座位,接着键入Group命令指导程序将Sequence中的标记分为不同的连锁群,接下来,程序在一个连锁群内部决定最有可能的标记排列次序,计算一个连锁群中所有的标记每一个可能的次序最大似然图谱,比较这些图谱的可能性并找出最合适图谱,这部分工作用Compare命令完成,再用sequence和map命令得到标记之间的连锁数据。之后,将这些数据按Genemap或MapDraw分析软件所要求的数据格式输入,通过对这2个软件的正确使用,就可得到需要的遗传连锁图谱图形文件。 展开更多
关键词 mapmaker3 0 Genemap mapDraw 遗传连锁图谱 连锁距离
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Composite-mask GAN based on refined optical flow and disparity map for SLAM visual odometry
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作者 JI Yuehui JIANG Jingwei +2 位作者 LIU Junjie SONG Yu GAO Qiang 《Optoelectronics Letters》 2025年第12期730-736,共7页
Although deep learning methods have been widely applied in slam visual odometry(VO)over the past decade with impressive improvements,the accuracy remains limited in complex dynamic environments.In this paper,a composi... Although deep learning methods have been widely applied in slam visual odometry(VO)over the past decade with impressive improvements,the accuracy remains limited in complex dynamic environments.In this paper,a composite mask-based generative adversarial network(CMGAN)is introduced to predict camera motion and binocular depth maps.Specifically,a perceptual generator is constructed to obtain the corresponding parallax map and optical flow between two neighboring frames.Then,an iterative pose improvement strategy is proposed to improve the accuracy of pose estimation.Finally,a composite mask is embedded in the discriminator to sense structural deformation in the synthesized virtual image,thereby increasing the overall structural constraints of the network model,improving the accuracy of camera pose estimation,and reducing drift issues in the VO.Detailed quantitative and qualitative evaluations on the KITTI dataset show that the proposed framework outperforms existing conventional,supervised learning and unsupervised depth VO methods,providing better results in both pose estimation and depth estimation. 展开更多
关键词 parallax map predict camera motion binocular depth mapsspecificallya slam visual odometry vo complex dynamic environmentsin deep learning methods generative adversarial network perceptual generator iterative pose improvement strateg
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Residual Attention-BiConvLSTM:一种新的全球电离层TEC map预测模型 被引量:1
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作者 王浩然 刘海军 +5 位作者 袁静 乐会军 李良超 陈羿 单维锋 袁国铭 《地球物理学报》 北大核心 2025年第2期413-430,共18页
电离层总电子含量(TEC)预测对提高全球卫星导航系统(GNSS)的精度具有重要意义.现有的TEC map预测模型主要通过顺序堆叠时空特征提取单元来实现.这种模型搭建方法会因多个卷积层顺序堆叠而损失细粒度的TEC map的空间特征,导致模型精度不... 电离层总电子含量(TEC)预测对提高全球卫星导航系统(GNSS)的精度具有重要意义.现有的TEC map预测模型主要通过顺序堆叠时空特征提取单元来实现.这种模型搭建方法会因多个卷积层顺序堆叠而损失细粒度的TEC map的空间特征,导致模型精度不够;还会由于多层堆叠导致梯度消失或梯度爆炸问题.本文借鉴残差注意力(Residual Attention)的思想,在TEC map预测模型中增加了残差注意力模块,提出了Residual Attention-BiConvLSTM模型.该模型中的残差注意力模块能同时提取粗、细粒度空间特征,并对其进行加权.本文在全球TEC map数据上与ConvLSTM、ConvGRU、ED-ConvLSTM和C1PG进行了对比实验.实验结果表明,本文所提出的Residual Attention-BiConvLSTM模型的RMSE、MAE、MAPE和R^(2)在太阳活动高年和年均优于对比模型.本文还在一次磁暴事件中对比了5种模型的预测效果.实验结果表明,大磁暴发生时,本文模型与C1PG相近,优于其他3种对比模型.本文的研究工作为电离层map预测模型搭建提供一个新思路. 展开更多
关键词 电离层TEC map预测 残差注意力模块 Residual Attention-BiConvLSTM 时空预测模型
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