冷藏运输管理系统应用

运用冷藏运输的方式将易腐食品和生鲜食品在流通环节中控制在适度低温环境下,成为了食品质量和安全的重要保障。随着冷藏运输行业的竞争加剧,各类冷藏运输企业迫切需要满足实际需求的信息管理平台,从而有效提高管理水平和效率。立足于冷藏运输企业的实际应用,针对冷藏运输企业的特点和现存的主要问题,除了基本的用户信息管理、运输信息管理、冷藏货物信息管理、运费管理、车辆管理等功能以外,设计实现对货物的实时温度监控、货物地方查询、意外故障报警等功能。     

一种有到达时问的多处理器混合流水车间调度的遗传算法

有到达时间的多处理器混合流水车间调度问题在实时机器视觉系统等领域有广泛的应用.这一问题是NP-困难的.鉴于以上原因,给出一种遗传算法.对不同的交叉算子和变异算子以及涉及的参数的不同取值进行试验,并对试验的结果进行分析和讨论,从而给出最好的参数组合.     

自动回单在宽带测速系统的实现简

本文介绍了自动回单在宽带测速系统中实现的流程,分析了其必要性、论述了其优点以及实现其的具体做法;最后提出了加入了新功能的宽带测速系统的发展方向。     

三维泡沫石墨烯在抗坏血酸的干扰下检测尿酸

该文采用化学气相沉积法在泡沫镍上生长石墨烯,通过扫描电镜、X射线衍射、拉曼光谱对生成产物的形貌和结构分别进行了表征。结果表明：所制得的石墨烯为具有三维网状结构且层数较少的石墨烯。将三维泡沫石墨烯转移到ITO玻璃上制成生物传感器的工作电极,利用电化学工作站对尿酸和抗坏血酸进行检测．电化学测试结果表明：三维泡沫石墨烯修饰电极在抗坏血酸的干扰下可以准确的检测尿酸,其灵敏度为0．274μA／（μmol／L）,线性范围为10-100μmol／L。     

A study on boundary force model used in multiscale simulations with non-periodic boundary condition

This paper presents an investigation of the non-periodic boundary condition (NPBC) which is often used in multiscale atomistic–continuum simulations. The relationship between the boundary force exerted by the imaginary atoms outside the atomistic domain and the fluid state parameters including density and temperature at the boundary is studied. A fitting formula of the boundary force as a function of the fluid state has been proposed based on the relationship. The accuracy of the fitting formula is verified by the equilibrium molecular dynamics (MD) simulations. Poiseuille flow with viscous dissipation and unsteady heat transfer between two walls is then simulated using the proposed fitting formula. The elimination of density oscillation near the boundary of atomistic region and good agreement of velocity and temperature evolutions with time from pure MD and the multiscale simulations adopting NPBC further confirm the correctness of our fitting formula.     

一步法合成新型稀土复合热稳定剂

研究了一种新型PVC稀土复合热稳定剂的合成工艺以及热稳定效果。用一步法合成了两种PVC稀土复合热稳定剂,讨论了两阶段碱分配比、各阶段反应时间、反应温度以及锌、钙、钡的含量对PVC稀土复合热稳定剂热稳定性的影响。结果表明:合成稀土-锌-钙复合稳定剂工艺条件是70℃、5min、15min、20min,稀土-锌-钡热稳定剂是65℃、15min、20min、5min,静态热稳定测试表明产物中的硬脂酸稀土与硬脂酸金属盐之间有良好的协同作用,两种复合稳定剂的静态稳定时间分别为18.6min、17.5min。     

Performance investigations of novel dual-material gate (DMG) MOSFET with dielectric pockets (DP)

Dual-material gate MOSFET with dielectric pockets (DMGDP MOSFET) is proposed to eliminate the potential weakness of the DP MOSFET for CMOS scaling toward the 32 nm gate length and beyond. The short-channel effects (SCE) can be effectively suppressed by the insulator near the source/drain regions. And the suppression capability can be even better than the DP MOSFET due to the drain bias absorbed by the screen gate. The speed performance and electronic characteristics of the DMGDP MOSFET are comprehensively studied. Compared to the experimental data from Jurczak et al., the DMGDP PMOSFET exhibits good subthreshold characteristics and the on-state current is almost the twice that of the DP PMOSFET. The intrinsic delay of the NMOS reaches 21% greater than the DP MOSFET for 32 nm node. The higher f _T of 390 GHz is achieved, which is a 32% enhancement in comparison with the DP MOSFET when the gate length is 50 nm. Finally, the design guideline and the optimal regions of the DMGDP MOSFET are discussed. Supported by the National Natural Science Foundation of China (Grant No. 60206006), Program for the New Century Excellent Talents of Ministry of Education of China (Grant No. 681231366), and the National Defense Pre-Research Foundation of China (Grant No. 51308040103)     

Evaluation of TiAl and 40Cr diffusion bonding quality using ultrasonic reflection spectrum

Combined with ultrasonic pulse-echo technique, reflection spectrum analysis was introduced to evaluate TiAl and 40Cr diffusion bonding quality. Frequency dependence of reflection coefficient was used to distinguish perfect bonding from imperfect bonding. It is found that the reflection coefficient from perfect bonding interface does not vary with frequency. When the size of imperfections is much smaller than the wavelength of ultrasound, the reflection coefficient depends on frequency. When the size of imperfections is the same order of or even larger than the wavelength of ultrasound, the reflection coefficient does not exhibit frequency dependence. However the amplitude of imperfect interface is higher than the amplitude of perfect bonding interface. A combination of reflection spectrum analysis and ultrasonic pulse-echo technique provides more accurate information about the bonding quality of dissimilar materials.     

Input electrical impedance as signature for nondestructive evaluation of weld quality during ultrasonic welding of plastics

As a wide applied joining process of plastics with long history, ultrasonic welding of plastics could be helped by newer technologies in sensing, pattern recognition, etc. to improve production rate and weld quality. This paper introduces a new concept which allows in situ monitoring of an ultrasonic welding process in real time and assessing the resulted weld quality right after the completion of the process. In the method, the input voltage and current of a welding machine are first probed and processed to obtain the input electrical impedance during the whole welding period. Because there are no changes of the dynamic properties of the welding machine and fixtures during the process, the detected waveforms of the real and imaginary part of the impedance directly reflect the thermo-mechanical behavior of the plastic work-pieces at the joining point. By recognizing the patterns of these waveforms, the joining quality could then be properly evaluated. This new concept and the accordingly derived nondestructive evaluation method were investigated experimentally. The results show that the input electrical impedance is an effective signature and that the built system evaluates bonding quality of welds effectively and efficiently.     

一种智能变电站环境信号管理模拟器的研制

无人值守智能变电站快速发展,对变电站辅助系统建设的智能、高效、兼容、自愈要求越来越高。但智能变电站辅助系统结构、标准均不规范,搭建真实的联动测试环境成本高,可行性较低且测试过程对整个系统设备要求苛刻。提供了一种基于IEC61850和Modbus等协议的智能变电站环境信号采集管理模拟器——智能管理主机模拟器。该模拟器内置符合Modbus的通信对象模型,通过IEC61850协议实现与综合应用服务器实现互联互通,同时模拟环境数据信号采集、控制命令、模拟配置管理、模型管理、监控查看、协议转换,从而实现智能变电站复杂环境的监测与控制。此外,通过实验测试,验证其可行性和实用性。