Performance of a divided flow exchanger

An analysis is presented of a 1-2 divided flow exchanger where the temperature of shell and tube streams depend on tube arrangement. Effect of having unbalanced tube passes is assessed for two possible cases. Graphs are plotted that show the variation of thermal effectiveness and logarithmic mean temperature difference correction factor with ratio of heat capacity rates and number of transfer units. Combination of such exchangers is also studied.     

Testing the relative conspicuity of safety garments for New Zealand forestry workers

The relative conspicuities of six test garments (fluorescent orange, green/red, high-contrast, fluorescent lime-yellow, white, black) were assessed to guide the selection process of a standard upper body safety garment to be used within the New Zealand logging industry. Six male and four female participants, aged between 18 and 26 years, volunteered to perform 10 trials each on a demanding, central (tracking) task, while peripherally searching colour slides for test garments displayed on each of eight positions, against a pine forest background typically found in the New Zealand forestry. During each trial, transparency luminance was first gradually increased from darkness to daylight and then decreased to darkness again within 180 s. A head mounted ASL eye tracking system (4000SU) recorded the eye line of gaze for each participant, enabling a rank order of detection to be obtained for the tested garments in each trial. The fluorescent lime-yellow, fluorescent orange and white test garments were detected earlier than any other test garments across all trials, and the fluorescent lime-yellow test garment was detected first with a higher frequency than the white test garment. It was concluded that while white may be the most visible colour in near darkness conditions, as it provides highest contrast, fluorescent lime-yellow stands out better in twilight and daylight conditions against the pine forest background. The results of this study led to the promotion of fluorescent lime-yellow as the standard safety colour used in upper body garments within the New Zealand forest industry.     

分隔型热耦合精馏塔的优化设计

针对多组分混合物的分离 ,建立了一种新型的分隔型精馏塔结构———分隔塔。通过简化为一个带有三塔的简单塔序列 ,建立其精馏过程优化设计的数学模型。以回流比、回收率为决策变量 ,总费用最小为目标函数 ,编制计算机程序进行优化计算。并以一C4物系为例进行了考核计算 ,与普通精馏比较节能效果显著     

烧结燃料二次分加优化试验研究

为进一步探明燃料种类及其搭配，燃料粒度等对燃料二次分加效果的影响，就二次分加时，无烟煤与焦粉的搭配顺序，焦粉粒度对钒钛磁铁精矿烧结指标的影响进行了研究。找出了适宜的燃料种类（焦粉）及其适应的粒度范围。为燃料二次分加工艺优化工业性试验提供了依据。     

对黑龙江省500kV变电所管理模式探讨

简述黑龙江省500 kV电网发展的基本情况,结合国内外500 kV变电所管理模式的成功经验,提出建立独立500 kV变电所监控中心,对500 kV变电所实施监控,对常规弱电控制变电所进行综合自动化改造,建立一个巡维中心,对所辖500 kV变电所定期巡视。这样可以减少运行人员,提高工作效率,对500 kV电力设备进行专门统一的细化管理。     

Application of Adaptive Divided Difference Filter on GPS/IMU Integrated Navigation System

The efficient and accurate approximate nonlinear filters have been widely used in the estimation of states and parameters of dynamical systems. In this paper, an adaptive divided difference filter is designed for precise estimation of states and parameters of micromechanical gyro navigation system. Based on the investigation of nonlinear divided difference filter the adaptive divided difference filter(ADDF) was designed, which takes account of the incorrect time-varying noise statistics of dynamical systems...     

城市道路绿化的几点思考

针对道路绿化的重要性,分析了城市道路绿化的意义,从城市道路分车带绿化、道路人行道上行道树、路侧带绿化三方面进行了分析研究,提出了具体的建议,从而更好地发挥城市道路绿化的作用。     

改进免疫算法在电力系统电源规划中应用

目前,遗传算法作为一种基手人工智能技术的优化算法在电力系统电源规划中已经得到广泛应用。然而其遗传操作繁杂、计算量庞大。易产生退化、早熟收敛等问题,使其应用受到局限。提出一种基于自然分段式编码的改进免疫算法MIA(Modified-Immune Algorithm),该算法具备全局多峰搜索能力。通过使用该算法可以大大简化电源规划的计算量、提高计算效率,并充分利用特征信息灵活求解,具备了更加优异的收敛特性,同时避免了退化、早熟收敛问题发生。     

多频谱红外烟幕干扰弹的反制方法

介绍了多频谱红外烟幕干扰弹的反制条件和反制时机;在可反制的阈值范围内,对烟幕遮蔽下的目标进行图像增强等预处理后,采用小波多分辨分析和分形布朗随机场模型,计算分形维数和分形拟合误差,从而判断目标所在区域;最后采用最佳熵自动阈值法确定分割门限,将目标从烟幕遮蔽中分割出来.实验证明,该方法效果明显,是对多频谱红外烟幕干扰弹反制最为关键的一步.     

基于神经网络的三极管温度特性模型研究

温度对三极管的性能影响较大,使得电路中的静态工作点出现不稳定现象．采用神经网络技术分析实际环境温度对三极管放大特性的影响,并通过实测数据和利用线性均差法得到的数据建立三极管温度特性的神经网络模型．利用该模型可预测温度对放大倍数的影响,掌握电路系统的温度漂移．从而为优化系统性能提供设计依据．