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黄志洵
《中国工程科学》 2005年 第7卷 第3期 页码 6-12
关键词: 狭义相对论 Maxwell方程组 Proca方程组 电磁波波速 光子的静止质量
Modeling, simulation, and prediction of global energy indices: a differential approach
Stephen Ndubuisi NNAMCHI, Onyinyechi Adanma NNAMCHI, Janice Desire BUSINGYE, Maxwell Azubuike IJOMAH,
《能源前沿(英文)》 2022年 第16卷 第2期 页码 375-392 doi: 10.1007/s11708-021-0723-6
关键词: energy indices differential model normalization simulation inflation/deflation predictive factor and prediction rate
姜伟
《中国工程科学》 2011年 第13卷 第5期 页码 66-73
郑永红,沈永明,吴修广,游亚戈
《中国工程科学》 2004年 第6卷 第4期 页码 34-40
研究了一种改进的Boussinesq方程,采用预报校正格式对该方程进行了数值离散,并对淹没潜堤上的波浪变形进行了数值模拟,从数值模拟结果和实测值的比较结果来看,该方程能较好地模拟波浪在潜堤上传播时波面的变形过程这种改进的Boussinesq方程本身及其求解方法需做进一步的完善。研究结果为实际应用Boussinesq方程来研究复杂地形上的波浪传播提供一定的理论指导。
关键词: 改进的Boussinesq方程 数值模拟 波浪变形 潜堤
曹结东,李永池
《中国工程科学》 2006年 第8卷 第1期 页码 40-45
通过唯象分析和细观统计相结合的方法建立了一种韧性材料的损伤演化方程,从物理上对方程中的参数进行了合理的解释,并以此为依据推导了材料的便于工程应用的几种层裂准则,根据准则总结了一些有意义的层裂规律;通过层裂实验和数值模拟相结合的方法来确定材料参数,计算结果与实验结果较好的一致性验证了所建的损伤演化方程和推导的层裂准则是合理的,决定材料参数的方法是有效的。
王勇,阮奇
《中国工程科学》 2006年 第8卷 第6期 页码 83-88
管内湍动流体摩擦因数是雷诺数和相对粗糙度的二元非线性函数,由Colebrook隐式方程计算摩擦因数要用迭代的方法求解,很不方便。为了得到形式简单、精度高的计算摩擦因数的显式方程,提出了二元非线性多项式智能拟合法。用该法拟合了Colebrook方程解的数据,得到一个计算管内湍动流体摩擦因数的显式新方程。方程的平均偏差为0.5%,最大偏差不超过1.8%,与实验数据偏差为2.3%。新方程具有形式简单、精度高、适用范围广的优点,且便于简化成光滑管或阻力平方区等情况下的计算摩擦因数的方程。
沈永明,郑永红,吴修广
《中国工程科学》 2004年 第6卷 第3期 页码 30-35
对2种典型的抛物形缓坡方程进行比较系统的数值研究。通过对4种典型地形上的波浪变形的数值模拟,详细讨论了网格节点数对数值解精度的影响、模型对初始入射角的敏感程度、非线性项对数值结果的影响等。研究结果可为实际应用抛物形缓坡方程研究大区域复杂地形上的波浪传播提供一定的理论指导。
林鹏,王长利,李焰,刘文祥,王等旺
《中国工程科学》 2009年 第11卷 第4期 页码 63-66
在单级轻气炮上对聚酯材料的激波状态方程进行了实验研究。最高撞击速度为526 m/s,相应在靶中得到的最高撞击压力为2.14 GPa。由实验结果拟合得到了聚酯材料的Hugoniot线性关系和多项式状态方程以及Grüneisen状态方程。
吴爱国,张小明,张钊
《中国工程科学》 2005年 第7卷 第10期 页码 11-15
介绍一种新型单级旋转倒立摆系统的构成,通过对其动力学特性的分析建立了基于Lagrange方程的数学模型。在平衡点附近给出系统的线性化模型,对系统的稳定性、能控性和能观性进行了分析。
关键词: 旋转倒立摆 Lagrange方程 最优控制策略LQR
杨培志,顾小松
《中国工程科学》 2006年 第8卷 第1期 页码 26-29
采用k-ε湍流模型对列车车厢内气流进行数值模拟需要消耗大量的计算时间,为此,提出了采用零方程湍流模型对列车车厢内的气流组织进行数值模拟;分别采用零方程湍流模型与k-ε湍流模型对列车车厢内的空气流动及传热进行了数值计算,经分析比较可知,该两种湍流模型的数值计算结果吻合程度较好,采用零方程湍流模型可大大缩短计算时间,利用其简单、快捷的特点,可以为列车空调系统的工程设计提供简便的数值模拟方法
唐军,沈永明,邱大洪
《中国工程科学》 2007年 第9卷 第4期 页码 70-74
双曲型缓坡方程是研究波浪在近岸缓坡区域传播变形的一种有效波浪数学模型。对Madsen和Larsen 提出的双曲型缓坡方程进行了数值模拟,数值模拟中采用时间层同步空间层交错的有限差分格式对双曲型缓坡 方程进行数值离散,并结合两个典型算例对所采用的数值模型进行验证。数值计算的结果表明,该数值模型可 有效地应用于双曲型缓坡方程的数值求解。
代谢组扩展生物学的“旁中心法则”——对理解基因组学-糖组学-代谢组学-表观基因组学互作的意义
Albert Stuart Reece
《工程(英文)》 2023年 第26卷 第7期 页码 16-16 doi: 10.1016/j.eng.2022.07.011
The central dogma of biology holds that the transcription of DNA into RNA and the translation of RNA into proteins forms the primary axis of biological activity [1]. Following major advances in the description of the complex glycan and lipid chains that are added onto these basic building blocks, the glycome and lipidome have recently been added to this doctrine as an exciting new extension named the ‘‘paracentral dogma” [2]. However, it has been pointed out that biological systems can include many layers, which are described in modern omics technology platforms relating to both cell-intrinsic and cell-extrinsic layers of control, including metabolomic, microbiomic, immunological, epigenomic, epitranscriptomic, proteomic and phosphoproteomic layers [3].
It is well known that stem and progenitor cells have a metabolism that is based on glycolysis and glutaminolysis [4]. Although this provides less energy to the cell than oxidative phosphorylation, it suffices for these cells’ needs, since such cells are generally relatively quiescent and normally suppress energy-intensive processes such as genome duplication and transcription. Moreover, it has been shown that the high intracellular lactate levels involved in such states not only inhibits the key gatekeeper enzymes of oxidative phosphorylation (i.e., pyruvate dehydrogenase and carnitine palmitoyl acyltransferase) but also actually covalently modifies them by lactylation in order to maintain this inhibited metabolic–epigenomic state [5]. In addition, intermediate metabolism and nutrients are the source of the very extensive library of post-translational modifications to DNA, RNA, and proteins, as well as supplying cellular energy for many of the required reactions. Hence, the metabolic state locks in and reinforces the epigenomic state, and the metabolome and epigenome thereby play mutually reinforcing roles. This self-reinforcing coordination explains why it is so difficult to generate induced pluripotent cells and is a contributory explanation for why the described protocols typically have such low cellular yields.
These concepts become even more important when it is considered that cancer cells are de-differentiated, similarly rely on glycolysis and glutaminolysis, and are similarly metabolically–epigenomically–genomically synchronized. The disruption of this metabolic system is a key focus of mechanistic cancer research.
These important considerations imply that the descriptive and predictive power of the newly described ‘‘paracentral dogma” of biology may be usefully and meaningfully extended by including the metabolome, along with the genome, transcriptome, proteome, glycome, and lipidome, to describe cell-intrinsic regulation—not only in terms of another omics analytical layer but also as a fully predictive and interactive partner in the symphonic-like multilayer coordination that evidently comprises cellular regulatory layering.
李炜
《中国工程科学》 2002年 第4卷 第1期 页码 82-88
概述了组播路由协议。分析了协议独立的组播路由一稀疏模式(PIM-SM)的缺陷,提出多个会聚 点(RPs)的PIM-SM的改进机制。分析了 PIM-SM实现细 节和组播技术的前景。
人类蛋白质N-糖基化的十二年全基因组关联研究 Review
Anna Timoshchuk, Sodbo Sharapov, Yurii S. Aulchenko
《工程(英文)》 2023年 第26卷 第7期 页码 17-31 doi: 10.1016/j.eng.2023.03.013
Most human-secreted and membrane-bound proteins have covalently attached oligosaccharide chains, or glycans. Glycosylation influences the physical and chemical properties of proteins, as well as their biological functions. Unsurprisingly, alterations in protein glycosylation have been implicated in a growing number of human diseases, and glycans are increasingly being considered as potential therapeutic targets, an essential part of therapeutics, and biomarkers. Although glycosylation pathways are biochemically well-studied, little is known about the networks of genes that guide the cell- and tissue-specific regulation of these biochemical reactions in humans in vivo. The lack of a detailed understanding of the mechanisms regulating glycome variation and linking the glycome to human health and disease is slowing progress in clinical applications of human glycobiology. Two of the tools that can provide much sought-after knowledge of human in vivo glycobiology are human genetics and genomics, which offer a powerful data-driven agnostic approach for dissecting the biology of complex traits. This review summarizes the current state of human populational glycogenomics. In Section 1, we provide a brief overview of the N-glycan's structural organization, and in Section 2, we give a description of the major blood plasma glycoproteins. Next, in Section 3, we summarize, systemize, and generalize the results from current N-glycosylation genome-wide association studies (GWASs) that provide novel knowledge of the genetic regulation of the populational variation of glycosylation. Until now, such studies have been limited to an analysis of the human blood plasma N-glycome and the N-glycosylation of immunoglobulin G and transferrin. While these three glycomes make up a rather limited set compared with the enormous multitude of glycomes of different tissues and glycoproteins, the study of these three does allow for powerful analysis and generalization. Finally, in Section 4, we turn to genes in the established loci, paying particular attention to genes with strong support in Section 5. At the end of the review, in Sections 6 and 7, we describe special cases of interest in light of new discoveries, focusing on possible mechanisms of action and biological targets of genetic variation that have been implicated in human protein N-glycosylation.
周旭
《中国工程科学》 2003年 第5卷 第9期 页码 36-38
标题 作者 时间 类型 操作
Modeling, simulation, and prediction of global energy indices: a differential approach
Stephen Ndubuisi NNAMCHI, Onyinyechi Adanma NNAMCHI, Janice Desire BUSINGYE, Maxwell Azubuike IJOMAH,
期刊论文