关于信息化测绘时代工程测量发展的思考

如今我国信息化技术全面发展，尤其对于工程测量工作领域来讲，不管是在工程建设和管理方面都产生不小的支撑引导效用。由此，笔者具体结合如今工程建设信息化测绘核心任何以及设备布置细节，进行结构整体安全管理周期和周边地理空间信息技术发展能效整理解析，试图将工程测量最新发展机遇和技术挑战问题处理完全。希望能够借此为日后一定时期范围内相关工程测量规划主体提供合理指导性建议内容，最终为我国各类工程事业可持续发展前景绽放奠定深刻适应基础。     

Influences of magnetic fields on current–voltage characteristics of gold-DNA-gold structure with variable gaps

Achieving highly sensitive magnetic sensors by means of Metal-DNA-Metal (MDM) structure is a key issue. DNA, being a genetic information carrier in living cells reveals tunable semiconducting response in the presence of external electric and magnetic fields, which is promising for molecular electronics. The influence of magnetic fields up to 1200 mT on the current–voltage (I–V) behavior of Gold-DNA-Gold (GDG) structure having variable gap sizes from 20–50 μm are reported in this work. These structures were fabricated using UV lithography, DC magnetron sputtering and thermal evaporation techniques. DNA strands were extracted from Boesenbergia rotunda plant via standard protocol. The acquired I–V characteristics display the semiconducting diode nature of DNA in GDG structures. The potential barrier for all the structures exhibit an increasing trend with the increase of externally imposed magnetic field irrespective of variable gap sizes. Furthermore, the potential barrier in GDG junction at higher magnetic field strengths (>1000 mT) is found to be considerably enhanced. This enhancement in the junction barrier height at elevated magnetic fields is attributed to the reduction of carrier mobility and augmentation of resistance. The achieved admirable features of magnetic sensitivity suggest the viability of using these GDG sandwiches as a prospective magnetic sensor.     

构皮滩水电站泄洪洞优化设计

构皮滩水电站为满足2008年12月工程提前发电的需要,结合现有泄洪洞地质情况和施工情况对泄洪洞布置进行了专题研究,结果表明利用降低进口高程为550 m的泄洪洞和坝身放空底孔联合参与后期导流,可缓解2007年导流隧洞下闸封堵后大坝在2008年汛期施工的压力,为大坝施工增加了2个月左右的工期。     

基于承包商预期收益不变的不平衡报价模型

在招标实践中,通常采用最低价中标原则,使得投标人不得不压低其投标价格。基于承包商预期收益不变的不平衡报价模型,是在“工程量清单报价”的条件下,考虑到施工中工程量的变化及施工顺序的影响,体现了资金的时间价值,在保持承包商预期收益不变的前提下,通过调整各分项工程的单价,来降低工程报价,以增加中标机会而建立的。所建立的模型简单,易于操作,并配以具体的工程实例,通过计算机求得其最优解,可供承包商投标报价时参考。     

新一代IP QoS的实现

文章介绍了新一代IP骨干网上的IP QoS实现技术，论述了集成业务(IntServ)与差分业务(DiffServ)解决方案的特点，详细介绍了相关的队列管理与排队机制。并结合多协议标签交换（MPLS)技术的最新发展，阐述了综合多协议标签交换流量工程与DiffServ技术体系端到端IP QoS的实现。     

我国上市公司股票评级研究——财务结构模型分析法在股票市场中的应用

目前,我国股票市场上的股票评级尚处于探索阶段,评级时多采用专家法或历史法,而对于影响股票评级的各因素的确定以及因素间的相互作用缺乏定量分析。研究将结构模型应用到我国股票市场的股票评级中,建立关于我国股票评级的财务结构模型;分析各个因素对股票评级的影响;建立股票评级经验模式值。     

A New Comb Circular Polarizer Suitable for Millimeter‐Band Application

This letter presents a new polarizer which has a simple comb structure inside a circular waveguide. The electrical performance of the proposed comb polarizer is optimized by a circular waveguide radius and by the physical parameters of the comb plates. This polarizer is suitable for providing good performance in millimeter‐band application because of its simple structure and low fabrication cost. In our experiments the dual‐band comb polarizer designed in band 1(K) and band 2(Ka) showed good electrical performance without any tuning elements.     

影响地下室防水工程质量的因素及对策

分析了影响地下室防水工程质量的主要因素，并对其质量控制提出了几点建议，可供实际工程参考。     

光缆接续损耗的工程控制

本从影响光纤损耗的主要因素分析着手，提出了光缆接续损耗工程控制的简洁有效的方法。