检索结果-南通市图书馆

Control of exterior ballistic properties of spin-stabilized bullet by optimizing internal mass distribution

Defence Technology（防务技术） 2019年第1期15卷 38-50页

作者： Janne Lahti Timo Sailaranta Mikko Harju Kai Virtanen Systems Analysis Laboratory Department of Mathematics and Systems AnalysisAalto University Aero RD Ltd Systems Analysis Laboratory Department of Mathematics and Systems AnalysisAalto Universit Department of Military Technology National Defence University of Finland

This paper introduces a novel approach for controlling the exterior ballistic properties of spin-stabilized bullets by optimizing their internal mass distributions. Specifically, the properties of interest are the bullets’ stability characteristics that are examined through dynamic and gyroscopic stability *** analytical expressions for aerodynamic quantities are also derived to address the compressibility of air. These expressions are utilized in a bullet model that enables efficient computation of the stability parameters for a given mass distribution. The bullet model is used in the formulation of nonlinear optimization problems that provide optimal mass distributions with respect to given goals, i.e., desired stability characteristics. The bullet types investigated in this paper are a long range bullet and a limited range training bullet. In the optimization of the mass distribution of the long range bullet, the goal is that the bullet stays stable for as long as possible. The mass distribution of the training bullet is optimized such that the bullet is stable at launch but becomes unstable shortly afterwards. The global optimal solutions obtained with the new approach fulfill the desired stability characteristics better than currently used uniformly filled bullets. Overall, the optimization approach reveals a new goal focused philosophy for bullet design compared to current trial and error design practices.

关键词： Aerodynamics Bullet exterior ballistics Mass properties Optimization Stability

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Blow up for Systems of Wave Equations in exterior Domain

引用

Chinese Annals of Mathematics,Series B 2019年第3期40卷 339-348页

作者： Xiuwen LUO School of Mathematical Sciences Fudan University

In this paper the author studies the initial boundary value problem of semilinear wave systems in exterior domain in high dimensions(n ≥ 3). Blow up result is established and what is more, the author gets the upper b... 详细信息

关键词： Wave equations exterior domain Blow up Lifespan

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Mixture prepared with Chinese medicines in terms of releasing exterior cold and clearing interior heat: its efficacy and safety in patients with seasonal influenza-a randomized controlled trial

引用

Journal of Traditional Chinese Medicine 2018年第5期38卷 746-753页

作者： Wu Zhisong Li Guodong Wei Wan Liu Zhaoheng Wang Wei Ma Ruihong Liu Wenhong Ma Jiaju Wang Yuguang Jiao Yang Department of Intensive care unit Dongfang Hospital Affiliated to Beijing University of Chinese Medicine Graduate School Beijing University of Chinese Medicine Department of Chinese Medicine Concord Hospital Affiliated to Fujian Medical University Department of Respiratory medicine Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University Department of Internal Medicine Dongfang Hospital Affiliated to Beijing University of Chinese Medicine

OBJECTIVE: To assess the efficacy and safety in 105 patients with seasonal Influenza in Beijing, the mixture prepared with Chinese medicines follows the treatment regimen of releasing exterior cold andclearing interior ***: Total 330 patients with seasonal influenza were enrolled and randomly and averagely divided into the Chinese herbal medicine, the western medicine and the Chinese patent medicine group. They were treated with Chinese medicine Oseltamivir Phosphate Capsules and the Scattering Wind and Resolving Toxins Capsules. The main efficacy indicators were the antifebrile onset time and recovery time of body temperature. The efficacy and safety of the mixture was scientifically evaluated. Comparisons of several variables were ***: Median antifebrile onset time of the Chinese herbal medicine group was significantly shorter than the western medicine group(P exterior cold and clearing interior heat could significantly shorten the fever time with safety.

关键词： Releasing exterior cold and clearing interior heat Influenza efficacy Mixture prepared with Chinese medicines

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

GLOBAL EXISTENCE OF THE SOLUTIONS TO NONLINEAR HYPERBOLIC EQUATIONS IN exterior DOMAINS

引用

Chinese Annals of Mathematics,Series B 1990年第3期11卷 315-329页

作者：陈韻梅高剑敏 Department of Applied Mathematics Tongji University

This paper deals with the following IBV problem of nonlinear hyperbolic equations utt- sum from i, j=1 to n ajj（u, Du）uxixj=b（u, Du）, t>0, x∈Ω, u（O, x） =u0（x）, ut（O, x） =u1（v）, x∈Ω, u（t, x）=O t>O, x∈（）Ω,where Ωis the exterior domain of a compact set in Rn, and |aij（y）-δij|= O（|y|k）, |b（y）|=O(|y|k+1), near y=O. It is proved that under suitable assumptions on the smoothness,compatibility conditions and the shape of Ω, the above problem has a unique global smoothsolution for small initial data, in the case that k=1 add n≥7 or that k=2 and n≥***, the solution ham some decay properties as t→ + ∞.

关键词： smoothness exterior hyperbolic deals assumptions decay compatibility instead reasoning lemma

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A MINIMIZATION PROBLEM ON exterior DOMAIN

引用

Acta Mathematica Scientia 1992年第2期12卷 154-162页

作者：严树森张正杰 ACAD SINICA INST MATH SCIWUHANPEOPLES R CHINA

In this paper, using the decay estimates for the solution of semilinear elliptic equation, we obtain the existence of a minimun for a minimization problem with nonzero data in the exterior domain.

关键词： semilinear elliptic estimates exterior minimization decay nonzero proof Nirenberg weakly

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

LARCH BARK TANNIN ADHESIVE FOR exterior PARTICLEBOARD

引用

Journal of Northeast Forestry University 1994年第4期5卷 79-82页

作者：刘志群李晓平陆仁书翁向丽 1. Northeast Forestry University China

The larch bark tannins were used to make adhesive for particleboard. The tanninadhesive in which 60% phcnol was replaced by tannin has 1 - 1 .5 month storage life and its cost is lower than that of PF resin. At the 10% and 9% rcsin solids content on dry wood chips, larch particleboard and poplar particleboard were made respectively. The physical properties of boards can meet the nccds of cxterior particleboard in German Standard DIN68763 V 100.

关键词： Larch bark tannin exterior particleboard Adhesive

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental Studies on Seismic Behavior of exterior SRUHSC Joints

引用

Journal of Harbin Institute of Technology(New Series) 2017年第5期24卷 61-70页

作者： Wei Liu Jinqing Jia State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology

To investigate the seismic behavior of the joints,six steel reinforced ultra high strength concrete( SRUHSC) frame exterior joints were tested. Three levels of axial compressive ratio varying from 0.25 to 0.45 were investigated to determine how this variable might influence the performance of the joints including failure mode,ductility,energy dissipation capacity,stiffness degradation,shear strength and shear deformation by the quasi-static cyclic test on SRUHSC exterior joints. This research program suggests that the design of joint should make full use of the joint panel deformation to dissipate energy of earthquake. It is tested that the value of 0.38 as a dividing point about the effect of axial compression ratio on the seismic performance of SRUHSC exterior joints should be taken into account in design. In addition,the increase of volumetric ratio of stirrup could possess the ductility for adequate response to unexpected strong earthquakes and a recommended value of minimum volumetric ratio of stirrup with high axial-load level is pointed out.

关键词： exterior joints ultra high strength concrete steel axial compression ratio

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The Liouville Type Theorem for a System of Nonlinear Integral Equations on exterior Domain

引用

Journal of Partial Differential Equations 2019年第3期32卷 191-206页

作者： YIN Rong ZHANG Jihui SHANG Xudong School of Science Nantong UniversityNantong 226000China Institute of Mathematics Nanjing Normal UniversityNanjing 270023China Institute of Mathematics Nanjing Normal University Taizhou CollegeTaizhou 225300China

In this paper we are concerned with a system of nonlinear integral equations on the exterior domain under the su让able boundary *** the method of moving planes in integral forms which has some innovative ideas we obtain that the exterior domain is radial symmetry and a pair of positive solutions of the system is radial symmetry and monotone ***,we can obtain the corresponding Liouville type theorem about the solutions.

关键词： System of integral equations exterior domain symmetry monotonicity Liouville type theorem

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Fitting on elements of exterior orientation utilizing SPOT-5 raw data file

引用

中国有色金属学会会刊：英文版 2005年第S1期15卷 35-37页

作者： SONG Wei-dong~1, WANG Wei-xi~1, HU Xing-hua~2 (1. Liaoning Technical University, Fuxin 123000, China 2. Liaoning Technical University, Fuxin 123000, China)

In traditional pattern, the calculation of elements of exterior orientation is to calculate the elements of image forming moment by using fundamental ground control points. Utilizing satellite raw data file directly, which holds abundant information and using the numerical analysis methods of modern mathematics, the parameter equations about each element of exterior orientation are adjused and the elements of image forming moment under some precision are calculated.

关键词： elements of exterior orientation ground control point numerical analysis parameter equation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Subspace Iteration for Calculating a Cluster of exterior Eigenvalues

引用

Advances in Linear Algebra & Matrix Theory 2015年第3期5卷 76-89页

作者： Achiya Dax Hydrological Service Jerusalem Israel

In this paper we present a new subspace iteration for calculating eigenvalues of symmetric matrices. The method is designed to compute a cluster of k exterior eigenvalues. For example, k eigenvalues with the largest absolute values, the k algebraically largest eigenvalues, or the k algebraically smallest eigenvalues. The new iteration applies a Restarted Krylov method to collect information on the desired cluster. It is shown that the estimated eigenvalues proceed monotonically toward their limits. Another innovation regards the choice of starting points for the Krylov subspaces, which leads to fast rate of convergence. Numerical experiments illustrate the viability of the proposed ideas.

关键词： exterior Eigenvalues Symmetric Matrices Subspace Iterations Interlacing Restarted Krylov Methods

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：