荒漠场景应用的车联网及其分簇路由算法

为了解决沙漠、戈壁等荒漠场景的车辆间及其与外界的通信,提出一种车辆自组织网络的体系结构并重点分析其分簇和路由算法。该算法根据网络中车辆所装备的通信终端类型和车辆定时发出的位置、速度和行驶方向等信息对车辆进行分簇。在簇内通信和簇间通信时,簇头车辆为簇成员车辆选择最合适的路由;在与外界通信时,簇头车辆为簇成员车辆选择最近的装备卫星或地面移动通信终端的车辆进行转发。仿真结果表明,该算法与传统的分簇路由算法相比具有更高的簇结构稳定性、更高的数据传输成功率以及更低的路由开销。     

对象—关系数据库中嵌套查询的设计与实现

在对象－关系数据库中,为了准确 表达对复杂对象的查询,针对其数据模型的特点,扩展了SQL查询语言,提出了三种嵌套查,研究了它们的语义及相关性,并给出了它们的实现算法,通过三种嵌套查询可以表达出更加丰富的查询语义,是对象－关系数据库查询语言的重要特征,该设计已在对象关系数据库ANGEL－Ⅱ中实现。     

白菜菜肴六款

(一) 海味千层白菜 原料:白菜1棵(用叶),虾仁、鱿鱼、鲤鱼肉各50g,盐8g,味精5g,鸡蛋1个,水淀粉6g,葱末、姜末各10g,香油6g。 制法:1.将白菜叶完整撕下洗净,用开水稍烫一下,摊开晾凉。 2.将虾仁、鱿鱼、鲤鱼肉治净,剁成馅放小盆内,放精盐、味精、鸡蛋、水淀     

ACAP塑料铝合金管通过鉴定

常州鑫海防腐塑料有限公司开发的ACAP塑料铝合金 管材日前通过技术鉴定。该产品强度高,在3～5?MPa压力 或撞击下,不破裂,不变形,抗老化,使用寿命是普通塑料管 的5～10倍,耐腐蚀,无毒,是金属管道和FRP管道的理想替 代品,且安装方便,采用传统的螺纹接口连接,可广泛用于民 用建筑、企业、大型商场、宾馆等的饮用冷热水输送和石油化 工企业等的化工产品的输送。????(刘魏)     

城市标识系统发展方向研究——以河南省兰考县为例

在我国新型城镇化和智慧城市建设的大背景之下,城市标识系统是城市精细化管理和城镇高质量发展的共同重要组成部分,标识系统的设计研究逐渐受到多方关注.文章通过总结国内城市标识系统研究理论,探索国内城市标识系统未来发展的方向,并在我国城市标识系统发展研究的基础上,结合兰考县城市标识系统现状,提出兰考县城市标识系统的设计策略和发...     

Sub-Terahertz Channel Sounder: Review and Future Challenges

Due to the large amount of unused and unexplored spectrum resources, the so-called subTerahertz(sub-THz) frequency bands from 100 to 300 GHz are seen as promising bands for the next generation of wireless communication systems. Channel modeling at sub-THz bands is essential for the design and deployment of future wireless communication systems. Channel measurement is a widely adopted method to obtain channel characteristics and establish mathematical channel models. Channel measurements depend o...     

Investigating the elliptic anisotropy of identified particles in p–Pb collisions with a multi-phase transport model

The elliptic azimuthal anisotropy coe cient (v₂) of the identified particles at midrapidity (■) was investigated in p–Pb collisions at■ Te V using a multi-phase transport model (AMPT).The calculations of di erential v₂ based on the advanced flow extraction method of light flavor hadrons (pions,kaons,protons,andΛ) in small collision systems were extended to a wider transverse momentum (p_T) range of up to 8 GeV/c for the first time.The string-melting version of the...     

Experimental and Numerical Analysis of a PCM-Integrated Roof for Higher Thermal Performance of Buildings

Phase change materials(PCMs) designate materials able to store latent heat.PCMs change state from solid to liquid over a defined temperature range.This process is reversible and can be used for thermo-technical purposes.The present paper aims to study the thermal performance of an inorganic eutectic PCM integrated into the rooftop slab of a test room and analyze its potential for building thermal management.The experiment is conducted in two test rooms in Antofagasta(Chile) during summer,fall,an...     

Bidirectional intensity modulated/direct detection optical OFDM WDM-PON system

In this paper, we have evaluated a bidirectional wavelength division multiplexing passive optical network(WDM-PON) employing intensity modulated/direct detection optical orthogonal frequency division multiplexing(IM/DD-OFDM). The proposed system employs 100 Gbit/s 16 quadrature amplitude modulation(16-QAM) downstream and 5 Gbit/s on-off keying(OOK) upstream wavelengths, respectively. The proposed system is considered low-cost as non-coherent IM/DD OFDM technology and a simple reflective semicond...