Some proximity and sensitivity results in quadratic integer programming

We show that for any optimal solution for a given separable quadratic integer programming problem there exist an optimal solution for its continuous relaxation such that wheren is the number of variables and(A) is the largest absolute subdeterminant of the integer constraint matrixA. Also for any feasible solutionz, which is not optimal for the separable quadratic integer programming problem, there exists a feasible solution having greater objective function value and with . We further prove, under some additional assumptions, that the distance between a pair of optimal solutions to an integer quadratic programming problem with right hand side vectorsb andb, respectively, depends linearly on b–b₁. Finally the validity of all the results for nonseparable mixed-integer quadratic programs is established. The proximity results obtained in this paper are extensions of some of the results described in Cook et al. (1986) for linear integer programming.This research was partially supported by Natural Sciences and Engineering Research Council of Canada Grant 5-83998.     

近炸引信炮口保险距离的计算

该文以国外某舰炮弹药无线电近炸引信为例,分析研究了该无线电近炸引信炮口安全保险距离有关的参量,通过对火药燃烧时间和电路延迟时间的计算推出了几种不同情况下该无线电近炸引信炮口保险距离,分析计算方法具有普遍性。     

英语主语和谓语动词在数方面的一致关系

英语中各种一致关系很多，但最主要的是主语和谓语在数方面的一致关系．就其一致关系必须遵守的语法一致、概念一致、近邻词一致等原则，论述了英语中主语和谓语在数方面一致的多种情况．     

迫弹配用近炸引信杀伤能力分析

文章通过建立迫弹杀伤能力计算模型，结合靶场试验数据．时迫弹采用预制破片和近炸引信后的杀伤能力进行了深入的分析，得到了许多有益的结论。所建立的模型和得到的结论。对于正确评价产品性能．改进弹药设计以及指导部队作战都具有重要意义。     

机器人光纤接近觉复合传感器解耦新方法

介绍了一种具有自补偿功能的光纤接近觉距离方位复合传感器的结构和工作原理，提出了一种基于多尺度特征的光纤接近觉复合传感解耦新方法，通过对传感信息的多尺度分辨级进行划分，进而采用不同精度的数值逼近方法实现对耦合方程的求解．文中介绍了该方法的原理、物理意义和具体实现过程．结果表明，该方法具有精度高、实时性好的特点，可以应用于存在类似问题的场合．     

全数字光纤传感测试系统的设计

为克服传统光纤传感测试系统器件分散性大、过程复杂等局限性，结合红外光电传感及物联网技术，设计了全数字光纤传感测试系统。该系统以MCU( Micro Control Unit) 为主控单元，采用红外接近传感器作为IＲLED( Infrared Light Emitting Diode) 驱动以及光电转换输出单元，ＲTC ( Ｒeal-Time Clock) 芯片及EEPＲOM( Electrically-Erasable Programmable Ｒead-Only Memory) 进行时间读取及光电数据的实时存储，WiFi ( Wireless Fidelity) 模块实现光电数据的网传、按键及LCD( Liquid Crystal Display) 显示单元完成人机交互等功能。实验结果表明，该系统可用于特殊环境下的非接触物体检测与颜色识别等场合，为进一步实现光纤传感测试系统的小型化及智能化提供了一种可行性方案。     

Edge proximity and matching extension in projective planar graphs

A graph $G$ with at least $2m+2$ vertices is said to be distance $d$ $m$-extendable if, for any matching $M$ of $G$ with $m$ edges in which the edges lie at distance at least $d$ pairwise, there exists a perfect matching of $G$ containing $M$. In this paper we prove that every 5-connected triangulation on the projective plane of even order is distance 3 7-extendable and distance 4 $m$-extendable for any $m$.     

Chromophore-Assisted Proximity Labeling of DNA Reveals Chromosomal Organization in Living Cells

The spatial arrangement of chromosome within the nucleus is linked to genome function and gene expression regulation. Existing genome-wide mapping methods often rely on chemically crosslinking DNA with protein baits, which raises concerns of artifacts being introduced during cell fixation. By genetically targeting a photosensitizer protein to specific subnuclear locations, we achieved blue-light-activated labeling of local DNA with a bioorthogonal functional handle for affinity purification and sequence identification through next-generation sequencing. When applied to the nuclear lamina in human embryonic kidney 293T cells, it revealed lamina-associated domains (LADs) that cover 37.6 % of the genome. These LADs overlap with heterochromatin hallmarks and are depleted with CpG islands. This simple labeling method avoids the harsh treatment of chemical crosslinking and is generally applicable to the genome-wide high-resolution mapping of the spatial chromosome organization in living cells.