Results 81 to 90 of about 230,931 (257)

嵌体修复下领第一磨牙残冠的三维有限元模型的建立

open access: yesZhongshan Daxue xuebao. Yixue kexue ban, 2005
【目的】建立带桩嵌体修复下颌第一磨牙残冠的三维有限元模型。【方法】制成第一磨牙残冠的制锁式带桩嵌体修复体的模型,将该模型置于水杯中,利用螺旋CT扫描,通过图像合成软件建立三维数字模型,结合大型有限元软件ANSYS进行建模。【结果】建成后三维有限元模型与实体组织具有良好的几何相似性。【结论】将牙体修复模型置于水中,经螺旋CT扫描并与有限元方法结合起来,可以建立复杂的牙模型,且能真实地模拟实际情况,使用性好。
连克乾   +4 more
doaj  

基于OAIS信息模型的起源信息封装策略研究与应用 [PDF]

open access: yes, 2017
[目的/意义]探索设计并实施长期保存系统起源信息封装策略。[方法/过程]首先分析 OAIS 信息 模型的详细组成,然后分析长期保存系统起源封装的特定服务需求,总结国际主流起源封装策略的基本特点, 提出基于 OAIS 信息模型的起源信息封装策略,并利用 Fedora 仓储系统的内容模型 FOXML 进行封装实现。 [结果/结论]该策略遵循 OAIS 及 PREMIS 标准,全面记录起源信息,具有灵活可扩展的特点,但同时管理和使 用相对比较复杂。
吴振新, 李文燕, 蒋世银
core  

Emerging applications of large language models in ecology and conservation science

open access: yesConservation Biology, EarlyView.
Abstract Large language models (LLMs) mark a major development in artificial intelligence, with potentially transformative implications for ecology and conservation science. Built on advanced deep‐learning architectures, these models can support a wide range of tasks. We reviewed emerging applications of LLMs, drawing on the wider scientific literature
Christos Mammides   +5 more
wiley   +1 more source

MSCT影像组学对Borrmann Ⅳ型胃癌与原发性胃淋巴瘤的鉴别诊断价值

open access: yesZhongshan Daxue xuebao. Yixue kexue ban, 2022
目的探讨CT影像组学模型鉴别Borrmann Ⅳ型胃癌与原发性胃淋巴瘤的价值。方法回顾性收集2008年6月至2018年4月经手术或内镜病理确诊的Borrmann Ⅳ型胃癌或原发性胃淋巴瘤的病例共186例,其中Borrmann Ⅳ型胃癌132例,原发性胃淋巴瘤54例。采用计算机软件对CT动脉期、静脉期图像提取放射组学特征,再选择Lasso Logistic回归方法进行特征筛选,并建立CT影像组学模型,此外亦筛选CT主观征象构建CT主观征象模型,并同时利用CT主观征象及组学特征构建联合模型 ...
陈钦贤   +7 more
doaj  

Insights for conservation from the Ecological Knowledge Games project

open access: yesConservation Biology, EarlyView.
Abstract Environmental conservation research requires robust methods for collecting large‐scale behavioral data and engaging diverse stakeholders in decision‐making processes. We (Y.P., A.B.D., and N.B.) created EcoKnowGames (Ecological Knowledge Games), a transdisciplinary project that develops knowledge games for conservation science and data ...
Yuan Pan   +4 more
wiley   +1 more source

平衡态和非平衡态等离子体的微观模型研究

open access: yesGaoya dianqi, 2005
总结和比较了当前主要的几种等离子体微观模型: Potapov模型、Eindhoven模型、基于动力学的模型和基于最小吉布斯自由焓原理的模型。前两种模型的理论依据都是道尔顿分压定律、质量作用定律、电荷准中性条件与化学计量平衡条件,但质量作用定律和配分函数的表达式不同:后两种一个是从化学反应动力学的角度,一个是从热力学和统计物理的基本定义出发,来描述等离子体的微观过程。分平衡态和非平衡态阐述了模型的变化:推荐了Eindhoven模型作为工程计算用的首选模型。
臧春艳, 何俊佳, 程礼椿
doaj  

Behavioral interventions to reduce demand for threatened freshwater turtles as pets

open access: yesConservation Biology, EarlyView.
Abstract Growing demand for freshwater turtles as pets has fueled illegal trade and accelerated wild population declines, underscoring the need for theory‐based demand‐reduction interventions. We conducted a three‐part randomized controlled trial with active turtle keepers (n = 1800) in China to test conservation‐ and legality‐framed messages by ...
Wuji Zheng   +9 more
wiley   +1 more source

输电线路雷击闪络分析中杆塔模型的研究

open access: yesGaoya dianqi, 2015
为更方便地计算输电杆塔各横担的电位以评估多回高塔的耐雷性能,建立了改进单波阻抗模型。基于电磁暂态计算程序,将新杆塔模型与传统的集中电感模型、单一波阻抗模型和多波阻抗模型对比,分析4种模型下塔身垂直方向上电位分布。采用反推法,由Hara多波阻抗模型推导出110、220、500 k V 3种电压等级下常见双回同塔和四回同塔高塔改进单波阻抗的推荐取值。研究结果表明,改进单波阻抗模型下的杆塔塔身电位分布与多波阻抗模型最为接近,在进行整条输电线路或者多基杆塔的防雷特性评估工作时,用改进单波阻抗模型代替多波阻抗模型,
黄文武   +6 more
doaj  

Motivation, Self‐Regulated R2W Strategy Use, and Their Relationship Patterns Among Different Writing Performance Groups

open access: yesInternational Journal of Applied Linguistics, EarlyView.
ABSTRACT The study investigated how writing motivation and self‐regulated read‐to‐write (SRL‐R2W) strategy use was related to writing performance and how the relationship between motivation and SRL‐R2W strategy use varied among different writing performance groups.
Huixuan Zhou   +3 more
wiley   +1 more source

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